text:
Home » Statement of the WPC regarding the presence of NATO in Palestine
In the year when NATO is completing 65 years of crimes and aggressions against humanity and 15 years after the murderous aggression of NATO against the peoples of Yugoslavia and the creation of its protectorate in the Serbian province of Kosovo, in the year when the NATO occupation and military presence continues in Afghanistan and Iraq and new recent crimes have been committed against the peoples of Libya and Mali, we consider that NATO has never served or will serve in future, peace in any region of the world, especially in the Middle East where the imperialist plans for a "New Middle East" adopted by the USA, NATO and its allies are openly being applied. The presence of NATO in the Middle East would only serve the plans of US and its allies of guaranteeing their influence and domination over the region.
The World Peace Council expresses its support and solidarity to the Palestinian people for the end of the occupation by Israel and for the creation of an independent State of Palestine within the borders of June 1967 with East Jerusalem as its capital. The "two-state solution" can not and will never be guaranteed by NATO, which constitutes the armed wing of imperialism and which is backing the Israeli occupation for decades now.
The WPC supported the efforts of the Palestinian people and its leadership to claim the legitimate recognition as full Member State at the UN and its bodies and does not agree at all with the replacement of the UN by NATO.
The WPC reaffirms its positions for the removal of the "Separation Wall" in the Palestinian West Bank, the lifting of the blockade on Gaza, the end of the occupation of the Syrian Golan heights and the Lebanese Shebaa Farms as well as the dismantlement of the Israeli settlements on Palestinian soil. The WPC demands the release of all Palestinian prisoners from Israeli jails along with the right of the Palestinian refugees for the return to their homeland based on the UN Resolution 194.
A possible direct involvement of NATO in the region would only deteriorate the existing tensions and conflicts, creating only further negative consequences for the peoples of the Middle East and for Palestine itself.
NATO, enemy of the peoples and of peace! Out of the Middle East!
The Secretariat of the WPC
wpc_on_nato_in_palestine.pdf


Celia Chase had 3 RBI in Warren's 11-1 win over Slippery Rock on Wednesday.
SLIPPERY ROCK, Pa. – After a two-hour bus ride, it took Warren's bats a little time to get going. When they did, the Dragons used a 10-run fourth inning en route to an 11-1 win in a rematch of last season's D-10 Class 4A title game.
Warren and Slippery Rock traded RBI hits from Celia Chase and the Rock's Julianna Hutchinson before Warren broke out. Chase and Hoffman keyed the 10-run inning with doubles.
Lex Nyquist finished with three hits, and Chase, Ellie Lobdell, Gracie Wood, Grace Wortman, and Morgan Munksgard two each for Warren (3-1). Lobdell scattered four hits in five innings, striking out eight.
Warren won the JV contest, 9-6. Alix Lytle was 3-for-3 with three RBI.
Kelsey Stuart struck out seven for the win, helped by solid defense from shortstop Meredith Morrison. Rylie Yeager and Ellee Irwin tripled, and Katie Madigan and Alex Neureiter had doubles in the win.
Nyquist SS 4-2-3-1, J.Lobdell 2b 4-1-1-0, Chase 1b 4-1-2-3, Hoffman 3b 3-1-1-1, E.Lobdell p 3-0-2-1, Irwin cr 0-2-0-0, Wood cf 2-1-2-0, Stuart rf 1-1-0-1, Wortman c 3-0-2-3, Morrison cr 0-1-0-0, Munksgard dp 3-1-2-1, Madigan lf 0-0-0-0. Totals 27-11-15-11.
Hutchinson c 3-0-1-1, Gresgott 1b 3-0-0-0, Hart 2b 2-0-0-0, Harty dp 2-0-0-0, Balino SS 2-0-1-0, Frazier p 2-0-0-0, Murdock, Kunsman rf 2-0-0-0, Sommers lf 1-0-0-0, Longdon 3b 2-1-2-0, Pence cf 0-0-0-0. Totals 19-1-4-1.
2b-Wood (W), Chase (W), Hoffman (W), Hutchinson (S). WP-E.Lobdell. LP-Frazier.


Correct and authenticated knowledge opens minds & liberates souls.
A Saint who gives scripture based worship of the Supreme God to his followers is in essence a Complete Saint. He is the complete knower of all the four Vedas, six shastras, eighteen Purans etc i.e. he will explain their essence.
A Saint or Guru or preacher who does not have the information about the Supreme God is an incomplete Saint.
Therefore that incomplete saint is unable to impart the true path of worship to his / her followers as a result of which the followers are not able to attain salvation / Moksh / Nirvana.
All those saints who consider Shri Krishna or Shri Vishnu ji or Shiv ji or Brahma ji as the Supreme God are incomplete saints.
They are not familiar with the Bhagavad Gita or Vedas or Puraans (Vishnu Puran, Durga Puran, Shiv Puran etc.) because in all these Holy Scriptures these Gods themselves accept some other God to be the Supreme God. Read Who is the Supreme God?
All those saints who consider Shri Krishna or Shri Vishnu ji or Shiv ji or Brahma ji as eternal are incomplete saints.
Bhagavad Gita, Shiv Puran, Durga Puran and Vishu Puran clarify that Brahma, Vishnu and Shiva are in birth and death. Those who say that Braham, Vishnu and Shiv live for ever and never die are incomplete saints and have no knowledge about our Holy Scripture.
All those saints who say that God is formless are incomplete saints.
All those saints who profess arbitrary worship like doing Pilgrimages, carrying out Shraadhs, having a dip in River Ganga as a means of salvation, doing forced meditation etc are incomplete saints.
Holy scriptures do not profess pilgrimages, carrying out shraadhs, bathing in River Ganga or doing forced meditation. These are arbitrary way of worship and no salvation can be achieved by doing all these activities. A saint who asks his followers to do such things is an incomplete saint.
All those saints who impart arbitrary mantras like Om Namah Shivaay, Om Namo Bhagvate Vasudevaay, Om Tat Sat, Hare Krishan, Ram Ram, Hari Om Tat Sat etc are incomplete saints.
All the above mantras are arbitrary and have no mention in our Holy Scriptures apart from Om Tat Sat which is a coded mantra. A saint who imparts such naams to the disciples is an incomplete saint and is playing with the lives of his disciples by misleading them.
© Supremeknowledge.org 2019 All Rights Reserved.


text:
Schneiderman Continues Media Strategy in Court Hearing with Meaningless "Bombshell" Claim
BY Katie Brown, PhD Mar. 22, 2017 1
New York Attorney General Eric Schneiderman's office attempted once again to manufacture an email controversy, proclaiming in a letter that Exxon had refused "to comply in good faith with OAG's investigative subpoena dated November 4, 2015," and characterizing it as a "bombshell" in a court hearing held today.
Meanwhile, here's the real bombshell: the Daily Caller has just reported that legal discoveries show Lem Srolovic, the Assistant Attorney General in Schneiderman's office, used a personal Gmail address to converse with activist organizations in 2012. This news comes just after Schneiderman's office tried to make a big deal about an alternate email for former Exxon president and CEO Rex Tillerson (which was a company-issued account, not a Gmail address, by the way) that was used to speed up communications with company leadership. Also let's not forget that Srolovic was the guy who told #ExxonKnew activist Matt Pawa not to tell a reporter that he secretly briefed the AGs ahead of their now infamous March 29th press conference with Al Gore.
It's worth noting that Schneiderman's office will appear in court next week to answer for his refusal to turn over emails between his office and major donors of the #ExxonKnew campaign – including the Rockefeller Brothers Fund, Rockefeller Family Fund, and billionaire activist Tom Steyer, which date back to before the original #ExxonKnew hit pieces by the Rockefeller-funded InsideClimate News and Columbia School of Journalism were published.
In court today, the judge made it very clear that a letter written on behalf of Exxon addressed many of Schneiderman's accusations, and he even highlighted a "rule of proportionality" regarding the AG's continued effort to gather more materials from Exxon – despite the thousands of documents already provided. ExxonMobil pointed out that the "rule of this Court" is that Schneiderman must consult with Exxon prior to taking the matter to court – of course, in his pursuit of headlines, Schneiderman failed to do this. From the letter on behalf of ExxonMobil:
"The Attorney General's fears of a widespread loss of data at ExxonMobil are entirely unfounded, and ExxonMobil is already taking steps to provide the Attorney General with the relief he seeks in his letter. Other than providing further evidence of his penchant for hyperbole and sensationalism in his ever-shifting investigation, the Attorney General's letter serves principally to highlight why consultation between the parties prior to seeking Court intervention is not just a rule of this Court, but also a prudent approach to routine discovery disputes like this one […] The Attorney General should have complied with this Court's rules and made a bona fide effort to pursue consultation before returning once again to court." (emphasis added)
Schneiderman's office attempted to justify this by saying that it had emailed Exxon its request for more documents and "Receiv[ed] no timely response…" But Schneiderman's office fails to mention it emailed Exxon only mere hours before it went to court and to the press. That's a pretty strange interpretation of "timely."
Today's hearing also puts the spotlight on how this entire dispute hinges on the fact that Schneiderman has changed the reason for his investigation no less than three times, after he realized that that his previous justification – namely #ExxonKnew – was not working out for him. Because of this, Exxon notes that Schneiderman originally said not to prioritize emails from senior management, or the "Management Committee Custodians," as his priority was documents from thirty years ago when he was investigating what Exxon "knew." Again, from the letter:
"The Attorney General faults ExxonMobil for not making a substantial production of documents from the Management Committee Custodians until the end of 2016 […] the Attorney General repeatedly instructed ExxonMobil to place the production of other custodians ahead of the Management Committee Custodians. In accordance with the Attorney General's priorities and initial investigative thesis, ExxonMobil first produced over 109,000 documents from four custodians who studied climate science […] " When these documents evidently refuted his investigative theory, the Attorney General informed ExxonMobil that his new "priority" was documents from certain enumerated custodians who contributed to the preparation of a 2014 report entitled "Energy and Carbon – Managing the Risks," and those on ExxonMobil's greenhouse gas issue management team. (Email from M. Wagner to P. Conlon, dated Feb. 3, 2016.) In those instructions, the Attorney General expressly stated that review of the custodial files of senior managers, such as Mr. Tillerson, was a secondary priority." (emphasis added)
As the letter further explains,
"The documents of the Management Committee Custodians became a priority for the Attorney General only after this Court rebuffed his efforts to obtain documents outside the scope of the subpoena, during a November 21, 2016 court appearance." (emphasis added)
All of this boils down to the fact that it's been nearly one year since Schneiderman hosted his March 29th press conference with Al Gore where the Democratic AGs touted their investigations of ExxonMobil. They have nothing to show for it – but if one thing has become clear throughout this process, they've certainly got a lot to hide.
climate, email, Eric Schniderman, ExxonKnew, ExxonMobil, Lem Srolovic, Rockefeller, Wayne Tracker

redpajama_set_name: RedPajamaCommonCrawl


text:
Clinks Care Farm nominated for a national Rural Oscar award
Amy Smith
Published: 9:04 AM October 19, 2017
Doeke Dobma pictured at Clinks Care Farm in Toft Monks. Picture: Archant. - Credit: Eastern Daily Press � 2011
A Norfolk farm which combines the care of land with the care of people has been nominated for a Rural Oscar award.
Clinks Care Farm is hosting its first pumpkin and squash market. Picture: Courtesy of Clinks Care Farm. - Credit: Archant
Clinks Care Farm in Toft Monks was nominated for the local food and drink category in Countryside Alliance Awards.
The awards, which are now in their 13th year, celebrate rural businesses, produce and communities.
Doeke Dobma, who runs the farm with his wife Iris van Zon, described the nomination as 'tremendous'.
He said: 'The awards are public-nomination led meaning that everyone has an opportunity to help vote for us and help us be recognised for what we do. They want to hear stories of what how we have helped and supported people and the local community but this needs to be done by November 13.
'In order to progress to the next stage and to stand a chance of being selected, we need support from as many people as possible with different experiences of Clinks Care Farm over the many years we have been working.
'If you have been touched by the work we do, in any way, we would ask that you go to the website and tell them about Clinks.'
Other recent achievements include the Box Scheme Delivery service, which sees the produce grown and reared at Clinks supplied to local shops and customers. The farm extended its box scheme customer base to 60 in September, and it's increasing. Produce is also sold at the Beccles and Loddon farmer's markets, with surplus produce donated to local foodbank and refugee groups.
Clinks recently celebrated seven years of its Farming on Prescription scheme, working with the NHS Great Yarmouth and Waveney Clinical Commissioning Group. The innovative scheme saw more than 200 patients suffering from mild to moderate mental health issues referred by their GPs, helping over 30 people return to the world of work.
To show support for Clinks Care Farm, visit www.countryside-alliance.org/caawards and nominate them under the food and drink category.
The farm is hosting its first pumpkin and squash market, which continues until October 31. The proceeds will go to the Sotterley Rural Resource Centre which aims to support ex-service personnel and people recovering from addictions.


Ava Max's 'Sweet but Psycho' slipped to Number 3 this week on The Official Big Top 40 as Calvin Harris and Sam Smith battled to be the new Number 1.
It was Calvin Harris who ended up on top, with his Rag'n'Bone Man collaboration 'Giant' taking the Number 1 trophy.
'Giant' becomes Calvin's ninth Number 1 on The Official Big Top 40, following on from 'Promises' with Sam Smith which went to the top at the end of 2018.
In a strange coincidence, it was actually Sam Smith who had to settle for Number 2 - his track 'Dancing With A Stranger' with Normani climbing four places this week.
The week's highest New Entry came from Ariana Grande with '7 Rings' making a huge impact on the chart at Number 4, just two days after it was released.
It's the latest track to be taken from her upcoming album 'thank u, next' and is likely to challenge Calvin and Rag'n'Bone Man for the top spot on next Sunday's show.
Rag'n'Bone Man joined Will Manning on FaceTime from his home to find out the news that he was Number 1.
Jax Jones and Olly Alexander were also on the show - with their track 'Play' at Number 7 this week - and Mabel joined Will in the studio to see her new song 'Don't Call Me Up' enter the chart after being released on Friday.
There were also New Entries from The Weeknd, Sigrid and American boyband Why Don't We.


text:
Month: August 2015 (Page 1 of 3)
To pap or not to pap: Some advice on news pictures and privacy – Amber Melville-Brown
August 31, 2015 / INFORRM / 0 Comments
A letter from the Queen means you've reached the ripe old age of 100. A letter from Kensington Palace may mean you've overstepped the mark snapping pictures of a royal prince. Continue reading
The Labour Party "purge" and social media privacy – Paul Bernal
The so-called 'Labour Purge' has many disturbing elements – from the motivations behind those who might 'need' to be purged to the motivations of those who want to purge them – but there is one aspect that appeared yesterday that seems to have been largely ignored: the attitude to people's privacy. Continue reading
How the Murdoch press has waged a relentless campaign against the BBC (and why it's worked) – Julian Petley
August 29, 2015 / INFORRM / 1 Comment
Ever since Rupert Murdoch decided to enter the television game in the early 1980s, his newspapers have waged continuous war on public service broadcasters, and on the BBC in particular. These he sees purely as rivals in the broadcasting marketplace, and when Murdoch spots rivals his instinct is to exterminate them – witness, for example, the predatory pricing by Murdoch of his newspaper titles by means of which he attempted to throttle the Independent in the early 1990s. Continue reading
Ashley Madison and the Shark Infested Seas of the Deep Web – Rhory Robertson and Clare Brown
The recent hacking of the Ashley Madison website has inevitably caused a vast avalanche of commentary, covering everything from users' morality to company security. As we concluded in our previous article apart from the fallout on people's personal lives from the data dump, the hackers' employment of the so-called 'dark web' to communicate their criminal acts needs further exploration. Continue reading
A Picture of Grief and Shock Too Far – Amber Melville-Brown
Yesterday I wrote a piece dealing with the privacy issues arising out of the Shoreham air disaster on this side of the Pond. With eerie timing, on the same day, America unintentionally watched live on TV the murder of two journalists, shot dead by a disgruntled former colleague at ABC News. Continue reading
Phone Hacking? You ain't seen nothing yet, Daniel Morgan murder case, 2000-2006 – Peter Jukes
Most people are aware of the phone hacking scandal and the high profile defendants at the 'trial of the century' last year. But neither Andy Coulson, nor Rebekah Brooks, nor phone hacking are anything like as important as the real scandal of the News of the World, which involves much more serious crimes that threaten the pillars of the criminal justice system in Britain. Continue reading
Air Crash Media: Photography, Privacy and Grief – Amber Melville-Brown
Car crash TV is defined in the Urban Dictionary as 'any TV programme that, like a recent car crash in the street, you know you shouldn't watch, you know you'll regret looking, but you just can't help yourself'. Continue reading
Comity for the Internet? Recent Court Decisions on the right to be de-indexed – Agnes Callamard
One of the most impactful events in global free expression jurisprudence development in 2014 was the the European Court of Justice Google Spain SL, Google v Agencia Espanola de Proteccion (2014) ("González") decision by on the so-called "right to be forgotten", more accurately referred to as the "right to be de-indexed". Continue reading
Is New Zealand the Libel World's most plaintiff friendly jurisdiction? – Ali Romanos
New Zealand defamation law strikingly favours plaintiffs. Sure, the Thai monarchy could be said to enjoy a certain degree of power, in view of the 25-year prison sentence imposed earlier this year on a businessman for some Facebook musings. But compared at least to their more temperate Common Law brothers and sisters, plaintiffs in New Zealand enjoy considerable advantages. Continue reading
News: ICO issues enforcement notice against Google to delist search results
On 18 August 2015, the Information Commissioner's Office ("ICO") issued an enforcement notice under section 40 of the Data Protection Act 1998 requiring Google Inc to remove nine links to web pages that include details of a minor criminal offence committed by the anonymised complainant nearly 10 years ago. Continue reading


Councillors on the Environment and Community Services Committee have today (November 9) given the go ahead for a feasibility study to be drawn up for a new motorway junction on the M4 at Emersons Green.
Funding of £500,000 has been secured from the Department for Transport towards the study, which will look at all the options of linking the M4 with the A4174 ring road with a new junction, 18a. The study will be steered jointly by the council and Highways England.
A key aim of the scheme is to ease congestion in this part of South Gloucestershire and provide better access to employment hubs such as the Emersons Green Enterprise Area, home to the Bristol and Bath Science Park.
Following today's decision, officers will get the technical work under way and appoint CH2M to work on the project. Work on the study is due to be completed in 2018.
As part of the study, there will be opportunities for people to give their views. Further details will be provided at a later date.


text:
the SCHOOL OF ARTS AND SCIENCES
Moland, MPP
Email: MarkMoland@letu.edu
Assistant Professor of History & Political Science
Program Coordinator for Criminal Justice & Human Services
Mark Moland joined LeTourneau in Fall 2015 after a 21 year career serving the United States Coast Guard. During his Coast Guard career, he coordinated multiagency law enforcement operations on the Great Lakes and in the Midwest, served on a multi-lateral arms control delegation in Geneva, Switzerland; and led daily high level Intergovernmental communications during the Deepwater Horizon (BP) Oil Spill of 2010. After teaching at the US Coast Guard Academy, Mark realized that his true calling was to the classroom. His greatest desire is to equip students" to work for the good of the city" to which they will be carried upon graduation.
Mark's research areas have focused on mass maritime migration, immigration policy and disaster response. Mark met his wife Shana in Geneva, Switzerland and they have been married for 11 years. Mark and Shana have three daughters, a son, and two dogs. They love books, game nights, Awana, and serving in their local church. Mark is also an avid cake decorator.
Doctor of Public Administration, California Baptist University (in Progress)
Master of Public Policy, Duke University
Certificate of Christian and Classical Studies, Knox Theological Seminary
Bachelor of Science in Government, US Coast Guard Academy
COURSES TAUGHT AT LETU
Personal and Professional Ethics
Intro to Criminal Justice
Terrorism and Counterterrorism
Justice and Human Rights
Division Chief for Policies & Competencies
U.S. Coast Guard Office of Boat Forces
Deputy Sector Commander
U.S. Coast Guard Sector Lower Mississippi
May-Aug 2010
Government Affairs Officer, Deepwater Horizon Oil Spill Response
National Incident Command
Chief, Response Operations
Assistant Dean of Academics; Executive Assistant
"Ready for reform: Reassessing the young offender, public defender and bail systems", World Magazine, 27 May 2017.
Panelist, One Book/One Region 2007: Across a Hundred Mountains, Immigration Panel Discussion, Groton Public Library, CT, July 27, 2007
PRESENTATIONS AND PANEL DISCUSSIONS
Panelist, U.S. Politics of Immigration: A Roundtable Discussion, Connecticut College, April 14, 2008
Master of Ceremonies, Preparing for the Next Cuban Migration, U.S. Coast Guard Academy April 28, 2008
Panelist, Navigation Committee: Response to 2011 Mississippi River Flooding" Ouachita River Valley Association Conference, El Dorado, AR, 23 August 2011.
Keynote, US Response to Deepwater Horizon Oil Spill, Navy League Memphis, December 2011.
Colson Center Centurion
American Society for Public Administration


text:
Gallery Dept. Announces Plans To Withdraw From The Fashion Industry
Courtesy of Gallery Dept.
Fresh off its mostly sold out collaboration with Lanvin earlier this year, Gallery Dept., the artful streetwear brand established by artist Josué Thomas four years ago, announced it plans to cease its fashion line.
Pinning the decision on the problematic nature of the industry, Thomas took to Instagram to make the announcement where he wrote, "We speak to the dissatisfaction with the monotony of the fashion industry polluting not only our minds, but the environment. Through mass media the ideology of consumerism is conflicting with our ethics and involvement in the conventional plane. I detest making disposable product."
H added, "Because each case is unique and deserves a unique solution, I am choosing to continue the practice of being an artist and withdraw myself from the fashion industry."
Established four years ago by Thomas In Los Angeles, Gallery Department has garnered a noteworthy amount of success with garments worn by Rihanna, Virgil Abloh and Taz Arnold, to name a few. Stocked at top-tier boutiques such as Ssense, Mr. Porter and Luisaviaroma, the brand's remaining inventory is also still available while on its gallerydept.com.
Gallery Dept.'s Los Angeles store closed on September 11, 2021. Thomas recently announced on his personal Instagram account that he plans to open Le Bar de music de la Galerie, a café and bar.
Check out Gallery Dept.'s full announcement below.
A post shared by GALLERY DEPT (@josuethomas)
Fashion News Rihanna Streetwear Lanvin Ssense Virgil Abloh


text:
#TBT: Inside Walt Disney's Home Theater
It's time for a Throwback Thursday. Perhaps this 1930's era home theater was Walt Disney's own 'happiest place on earth.'
Jason Knott	• May 25, 2017
For Throwback Thursday, let's go back to 2011 when CE Pro looked at Walt Disney's 1930's-era home theater.
Walt Disney's old home in Los Angeles is up for sale and it gives us an interesting glimpse of his private home theater.
The four-bedroom, five-bath, 6,388-square-foot Los Feliz-area home is going for $3.65 million. Inside the 12-room chateau-style house, Disney converted a guest room, bath and library into a home theater to watch dailies and enjoy private screenings of his films and other classic movies.
There is not much detail about the equipment in the home theater. According to the LA Times, the room was originally a family room, but when Disney began creating live-action films vs. just animated movies, he decided he needed an area to view the dailies, so the room was converted.
Walt Disney's 1930's era home theater. See more photos.
The projector was a 35mm commercial-grade unit built back in the era. There still is a built-in 4×3 aspect ratio film screen encased in a wood wall at one end of the room.
There is a clearly a large horizontal center channel in-wall speaker above the screen.
In the other end of the home theater, Disney had a small separate projection booth constructed. The projectionist's room had its own toilet and a small bar. The original sink is still there. It's pretty amazing that subsequent owners of the house have kept the original home theater in place (except the old projector of course) without updating it.
According to the LA Times, Disney's daughter recalls watching "Citizen Kane" and "Gone with the Wind" in the room.
Walt Disney's home. See more photos.
Jason Knott:
Jason Knott is Chief Content Officer for Emerald Expositions Connected Brands. Jason has covered low-voltage electronics as an editor since 1990, serving as editor and publisher of Security Sales & Integration. He joined CE Pro in 2000 and serves as Editor-in-Chief of that brand. He served as chairman of the Security Industry Association's Education Committee from 2000-2004 and sat on the board of that association from 1998-2002. He is also a former board member of the Alarm Industry Research and Educational Foundation. He has been a member of the CEDIA Business Working Group since 2010. Jason graduated from the University of Southern California.
View Jason Knott's complete profile
Audio/Video • News • Slideshow
Installation • TBT


There are more Jews attending Passover Seders than Yom Kippur services, according to a Pew Research study, but those spending the Holiday of Freedom in hospitals are usually unable to participate. Not anymore! With the new Seder-to-Go kit produced by Chabad on Call, chaplains and rabbis within the medical community now have a great resource for individual or hospital-friendly celebrations.
Many hospitalized or homebound patients feel isolated and a profound disconnection from normal life, shared Rabbi Shalom Stiefel, director of Chabad of Arcadia in California. "We have the power to give them hope and strength just by being there for them as another human being." Stiefel plans to deliver thirty Seder kits to patients at his local hospital.
The elegantly designed box includes a Seder guide and Hebrew-English Haggadah, a Seder plate placemat that fits neatly in a hospital tray, a matzah bag, and labeled containers for each of the Seder plate food items that can be filled by the local emissaries. After the positive feedback from last year's pilot run of the Seder-to-Go kits, Chabad on Call produced more this year for distribution. They've shipped 3,050 to date and are expecting more orders closer to the holiday.
Aside from the easy set-up and aesthetics of the kit, it also ensures the recipient has all the unique traditional items necessary for a complete Seder without cutting corners. And the kits show the recipients that someone is thinking of them during their vulnerable times.
To that end, they've also produced a Shabbat kit, a booklet of selected Psalms and inspirational messages, and a cultural awareness course for medical staff.
Volunteer poses with Seder kits to be distributed at the local hospital.
Rabbi Yitzchok Bergstein, Chabad of Oak Park, Illinois, distributes the kits to people who can't make it to the Seder like this medical student.
The Seder-to-Go, unpacked and ready to use.


I am re-reading Rhinoceros Success by Scott Alexander. Scott Alexander is the author of 3 books: Rhinoceros Success, Advanced Rhinocerology and Rhinocerotic Relativity. The Rhinoceros Success books are on my list of favorite success books. I read the first one Rhinoceros Success, years ago. I have read all three many times.
The RHINO charges thru life making things happen as opposed to the cow who waits for things to happen. The real secret to success for anyone is, of course, to figuratively become a rhino. You need to wake up tomorrow morning as a romping, stomping, full-grown, six thousand pound rhinoceros, charging toward your goals.
If you aren't 100% completely satisfied with your life, then get mad and do something about it. Charge!!! You should say to yourself, "I will not be a lazy cow grazing in the pasture day after day! I won't be one of those students who does nothing, sees nothing, accomplishes nothing and worse off — settles for just doing O.K. I woke up this morning as a rhinoceros! I am going to sacrifice the security and complacency of the pasture and live a rhinoceros life of excitement and adventure in the jungle…" (Alexander, p.14).
Since I first read Rhinoceros Success, I started collecting rhinoceros figurines and pictures for my office. They remind me to act like a rhino and charge full steam ahead towards my goals.
The Rhinoceros Success books had a big impact on me. They are on my recommended reading list.


We hope you can find what you need here. We always effort to show a picture with HD resolution or at least with perfect images. Motorisation Pour Portail Coulissant Moteur Pour Portail Coulissant Idees De Dcoration can be beneficial inspiration for those who seek an image according specific categories; you can find it in this site. Finally all pictures we have been displayed in this site will inspire you all..


Specializing in Affordable Custom Small Business & Non-Profit Organization Websites. We try to create only original, professional, and interactive websites that will help you generate more business, generate and manage leads, communicate better with customers and help you become more efficient. All at the lowest prices available in today's market.
Services currently offered include website design, hosting and domain name registration, site promotion, and much more. Everything you need to get started and maintain for a powerful presence on the web. For additional information on services and their prices, please see their respective pages.
What good is a great looking site if nobody can find it? Let us help you get your website noticed though search engine optimization, registration, ads, and more.
What we offer to our clients !
Website Designing covers many different skills and disciplines that are used for developing a website. The different areas of web designing include; web graphic design, interface logo design, Brochures and catalogs, user experience design and Search Engine Optimization.
Him Tech Logics is one of the leading website application development companies in Chandigarh, Mohali, Panchkula, Himachal, India.Our company develops custom Web site applications and software across a wide range of technology platforms to ensure successful implementation of your business strategies.
Our aim is to offer you the best Search Engine Optimization (SEO) Chandigarh, India. Website marketing package designed to capture a notable presence in cyberspace, which is guaranteed to catapult your business to unprecedented heights.
Him Tech Logics is a team of professional expertise, we strive to provide custom software development Solutions that will help you remain in step with your competition by continuously improving your information technology based business solutions.
Him Tech Logics specialized in providing Website Designing , Website Development , Internet Marketing , Content Development , Content Management System , Logo Designing , Website Banners , Flash Banners , Software Development and Search Engine Optimization (SEO) in Chandigarh, Mohali, Panchkula, Himachal, Other States of India and all over the World.
HTL did a Great job with our project. They worked with me on the design and function until I was satisfied. Their technical and designing skills are great with PHP and I would recommend them for designing a website.
New Domain Or Sub-Domain - How To Start A New Website?


text:
\section{Introduction}
Understanding the chemical evolution during the transformation of atomic gas to molecular gas
of the clouds is crucial to construct a complete picture of the evolutions of the interstellar medium (ISM).
In the transition phase of molecular clouds,
such as from the diffuse phase to the translucent phase and then to the dense phase,
physical changes of the environments affect the local chemical states.
Molecules and their associated chemistry, such as hydrocarbon chemistry, sulfur-containing molecular chemistry and
complex organic molecular chemistry, are imprints of the evolutions of ISM.
The choice of suitable tracers that represent the chemistry could
reflect the changes of physical processes as well, thus the evolution of star formation \citep{Aikawa2001}.

One process in such a transitional phase is the transformation of atomic hydrogen to
molecular hydrogen on the grain surface at low temperatures \citep{Cuppen2006}.
Another set of widely recognized process is the transformations between C$^+$, C and CO
during the transition from the diffuse phase to the dense phase of a cloud \citep{Lee1996}.
The transformations of species from atomic to molecular form, or from simple to complex form indicate that the chemical
complexity is increasing with the evolution of the clouds.
Thus, it is worth exploring other kinds of molecules, such as sulfur-bearing molecules
and grain surface species, as tracers in these transitional phases.
Moreover, the boundaries defined by different tracers may be characterized by
different physical conditions, such as density or temperature \citep{Goldsmith2010}.
Thus, the study of the chemistry of different molecules could benefit our understanding of
the physical environments.

The elemental sulfur abundance is severely depleted in dark clouds while maintaining its atomic form in
diffuse clouds \citep{Vidal2017, Laas2019}. Thus, there should be a transformation for sulfur-bearing
species if we analogize the sulfur chemistry with the carbon chemistry.
As stated above, dust grains are important for the formation of H$_2$.
Other species could also stick onto the surface of grains, diffuse among the sites and recombine to form new species.
Water ice is generally observed on the line-of-sight dense clouds toward background stars.
At the diffuse ISM condition, water ice is expected by the laboratory experiments \citep{Potapov2020}.
However, there was no strong evidence for the existence of solid-state water in the diffuse-dense transition \citep{Poteet2015}.
The presence of water ice is important for the depletion of elemental oxygen in the gas of diffuse ISM, which
could be explained if the missing oxygen is in the oxygen-bearing solid form in the grain ice mantles \citep{Poteet2015}.
On the other hand, the detection of larger complex molecules, such as CH$_3$OH in the diffuse
and translucent clouds \citep{Thiel2017, Liszt2018} could also be explained by the grain surface origin.
The chemical composition of grain ice mantles in the diffuse-dense transition is poorly constrained
because of the observational difficulty in the identification of interstellar ice mixture.
\citet{Esplugues2019} studied the ice chemistry in the photodissociation regions (PDRs)
where high UV radiation is present, which results in poor ice compositions (i.e~less than one monolayer when A$_V$ $<$ 2 mag).
With respect to the PDRs, the UV radiation in the outer extended regions of the dark clouds is much lower,
so that a relatively rich ice composition could be developed in that region.
Thus, the comparison of the ice composition between the outer and inner regions of the dark clouds
could be more meaningful compared with the PDRs.

The Taurus molecular cloud (TMC) has been chosen as the target by \citet{Goldsmith2010}, \citet{Xu2016a} and \citet{Xu2016b}
to study the boundary conditions indicated by H$_2$ emission, OH and CH physicochemical properties, respectively.
Taurus molecular cloud-1 (TMC-1) is one of a nearest clouds with a distance of $\sim$140 pc \citep{Elias1978}.
It is in a place where the low-mass star formation process is ongoing
and is currently close to gravitational equilibrium \citep{Feher2016}.
It is also in an environment that is less affected by the external radiation field \citep{Xu2016a} compared with the PDRs,
making it an ideal source for the study of chemical evolutions.

Observationally, many species have been detected in the diffuse and translucent phases,
indicating that chemical complexity has been developed in these regions \citep{Snow2006, Liszt2018}.
With relatively low density and low extinction, many small hydrocarbons
and ions survived \citep{Lucas2000, Liszt2018, Thiel2019}.
With the accretion of the gas, the molecular species diversity also increases.
Examples are the detection of cyanopolyyne species \citep{Suzuki1992}, methanol and even more
complex organic molecules (COMs) \citep{Soma2015, Soma2018} in the dense part of TMC-1.
More recently, more than two dozens of molecules have been detected in TMC-1,
including the long carbon chain molecules
\citep{Xue2020, Loomis2021, Shingledecker2021, Cernicharo2021f, Cabezas2021b, Marcelino2021},
circular and aromatic molecules \citep{McGuire2021, Burkhardt2021, Cernicharo2021c},
unsaturated hydrocarbons \citep{Agundez2021a, Cabezas2021a, Cernicharo2021e},
oxygen-bearing COMs \citep{Agundez2021b, Cernicharo2020b, Cernicharo2021a},
sulfur-bearing molecules \citep{Cernicharo2021b, Cernicharo2021d},
and nitrile anions \citep{Cernicharo2020a}.
A systematic check of the chemistry based on this large number of observed molecules could give a
new insight into the constraints of the chemical reaction network.

Many observational and theoretical studies have focused either on
the chemistry in diffuse or translucent part \citep{Lucas2000, Liszt2018, Thiel2019} with extinctions
less than $\sim$5 mag or on the dense part of TMC-1 CP (the cyanopolyynes emission peak) or TMC-1 NH$_3$
(the ammonia emission peak) \citep{Soma2015, Soma2018, Loison2017, Majumdar2017, Maffucci2018}.
It is interesting to explore the chemical variations from the diffuse
to the dense part of the TMC-1 \citep{Lee1996, Fuente2019}.
\citet{Turner2000} studied the chemical variations from the diffuse to translucent clouds
at extinction in the range from $\sim$1 to 5 mag by using the pure gas-phase chemical models.
More recently, \citet{Federman2021} studied the changes of the physical conditions
from diffuse gas to molecular gas for four different line-of-sights toward background star
in TMC by multi-wavelength observations. \citet{Bron2021} explored the different tracers
of the ionization fraction in translucent and dense gas.
In this paper, by combining the most recent observationally derived physical properties of TMC-1 and
the state-of-the-art astrochemical simulations from diffuse to dense phase
that across the TMC-1 boundary with the extinctions range from 1 to 20 mag,
we investigate the chemical variations in these transitional regions
and study the chemical properties of most important molecules that may serve as the tracers of these regions.

The organization of this paper is as follows. In Section \ref{sec.model}, we describe the
changes of the physical conditions from the ridge of TMC-1 filament to the outer extend regions,
and the chemical models used for the evolution of the chemistry across a span of virtual extinction.
Section \ref{sec.result} shows the results at the dense part of the TMC-1 CP by comparison with
observations to constrain the chemical model parameters, and then shows the chemical variations as a function
of extinction across the TMC-1 boundary.
Finally, we discuss our predicted results in Section \ref{sec.discuss}
and highlight major findings in Section \ref{sec.conc}.

\section{Physicochemical models of TMC-1 boundary}\label{sec.model}

\subsection{Physical parameters description}
Along and near the TMC-1 filament, there are three observational emission peaks,
namely TMC-1 CP (the cyanopolyynes emission peak), TMC-1 NH$_3$ (the ammonia
emission peak) and TMC-1 C (the dust continuum peak).
As shown in Figure 1 of \citet{Fuente2019}, starting from the three emission peaks,
there are six cutting points extending horizontally to the edge of the molecular cloud.
They represent the transitional regions from the inner dense phase to the outer translucent phase.
The physical conditions of the model are extracted from \citet{Fuente2019} in which for each point
the dust temperature, gas temperature, H$_2$ column density and volume density were derived.
The dust temperature is derived from the \textit{Herschel} Gould Belt Survey, and the gas temperature
and n(H$_2$) are derived by fitting the molecular lines of CS and its isotopologues.
The extinction is derived by $N(H_2) = A_V \times 10^{21}$.
The total hydrogen nuclei density n$_H$ equals to n(H) + 2n(H$_2$).
Here we assume the majority of matter is occupied by H$_2$, thus n$_H$ $\approx$ 2n(H$_2$).
We list these physical parameters in Table \ref{tab.para}.

\begin{table}
\caption{Physical conditions along the three horizontal lines starting from the three emission peaks in TMC-1 filament.}
\label{tab.para}
\begin{tabular}{lllll}
\hline \hline
             & T$_{dust}$ & T$_{gas}$ & A$_V$ & n$_H$  \\
             & (K)      & (K)     & (mag) & ($\times$ 10$^4$ cm$^{-3}$) \\
\hline
TMC-1 CP     & 11.92 & 9.7   & 18.20 & 3.0 \\
offset 1     & 12.00 & 10.2  & 16.71 & 4.6 \\
offset 2     & 12.24 & 11.2  & 13.74 & 7.4 \\
offset 3     & 13.16 & 12.5  & 7.27  & 0.3 \\
offset 4     & 13.86 & 16.0  & 4.77  & 0.54 \\
offset 5     & 14.39 & 14.7  & 3.25  & 0.32 \\
\hline
TMC-1 NH$_3$ & 11.70 & 11.8  & 16.97 & 4.0 \\
offset 1     & 11.79 & 10.2  & 15.58 & 2.4 \\
offset 2     & 12.12 & 12.7  & 12.88 & 3.0 \\
offset 3     & 13.10 & 11.9  & 10.04 & 0.58 \\
offset 4     & 13.78 & 11.4  & 4.04  & 0.32 \\
offset 5     & 14.00 & 13.5  & 3.00  & 0.58 \\
\hline
TMC-1 C      & 11.26 & 8.5   & 19.85 & 9.0 \\
offset 1     & 11.32 & 10.3  & 18.47 & 8.6 \\
offset 2     & 11.67 & 11.6  & 13.34 & 2.38 \\
offset 3     & 13.13 & 11.1  & 4.79  & 0.58 \\
offset 4     & 14.08 & 13.5  & 2.20  & 1.1 \\
offset 5     & 14.53 & 13.5  & 1.63  & 0.52 \\
\hline
\end{tabular}
\\

Notes.\\
Physical parameters from the three emission peaks to the outer extend regions of TMC-1.
For each set of parameters in TMC-1 CP, NH$_3$ and C,
the first row corresponds to the observational molecular emission peak in the TMC-1 filament,
while the other rows are the horizontal extensions starting from the emission peak.
Data are taken from \citet{Fuente2019}
(the T$_{dust}$ and A$_V$ in the sixth row of TMC-1 NH$_3$ set have been corrected by the author).
\end{table}

\subsection{Chemical model description}
We use the two-phase (gas phase and grain surface) model of NAUTILUS \citep{Ruaud2016}
to perform the astrochemical simulations.
The full gas-grain reaction network is the same as used in \citet{Vidal2017}, which is considered
the up-to-date sulfur chemistry to solve the elemental sulfur depletion problem, and has been
tested at the TMC-1 CP.
This network is based on kida.uva.2014 \citep{Wakelam2015} and \citet{Garrod2006}.
We also modified the network with additional reactions related to C$_3$H and C$_3$H$_2$ isomers from \citet{Loison2017},
namely linear and cyclic configuration, which are widely detected in the interstellar
medium including in the diffuse and translucent environments \citep{Turner2000, Gerin2011}.

Basically, kida.uva.2014 is the gas phase network, which includes various types of reactions,
such as ion-neutral and neutral-neutral reactions, cosmic-ray and UV-photon dissociations.
In addition to the gas phase chemical reactions, there are also grain surface reactions,
and interchange processes between gas phase and grain surface species.
The gas phase species can be adsorbed to and diffuse on the grain surface and react with other surface species.
In addition to including the thermal desorption and cosmic-ray desorption of grain surface species,
the network also includes the chemical desorption, which is the desorption by exothermicity
of surface reactions \citep{Garrod2007} with an efficiency of 0.01.
The ratio of diffuse to desorption energy of a grain surface species
is set as the default value of 0.4 \citep{Garrod2006, Chang2012}.
As for the strength of the interstellar radiation field,
the cosmic-ray ionization rate is set as 5 times the standard value of 1.3 $\times$ 10$^{-17}$ s$^{-1}$,
and the UV factor is set as 3.8 in habing unit.
These two values are consistent with the PDR model results \citep{Fuente2019} where different values of cosmic-ray
ionization and UV factor are used to fit the gas ionization fraction and the relation between dust temperature
and A$_V$, respectively.
We do not distinguish the difference between the grain surface and grain ice mantle species.
As for other parameters used in the model, the gas-to-dust mass ratio is 100,
and we assume a spherical silicate dust grain, with a commonly used radius of
0.1 $\mu$m and a density of 3 g cm$^{-3}$.
We also assume the number density of grain surface sites is 1.5 $\times$ 10$^{15}$ cm$^{-2}$.

Due to the low extinction in the boundary of the TMC-1 filament as shown in Table \ref{tab.para},
the shielding for H$_2$ and CO should be important.
NAUTILUS includes the self-shielding of H$_2$ \citep{Lee1996},
CO self-shielding and cross-shielding by H$_2$ and dust \citep{Visser2009},
and the shielding of N$_2$ by H$_2$ and N$_2$ \citep{LiXiaohu2013}.

The initial elemental abundances are chosen from \citet{Semenov2010} with the exception of C$^+$, O and S$^+$
because of the importance of these elements on the chemistry.
\citet{Agundez2013} has shown that a carbon-poor, oxygen-rich condition (C/O = 0.55)
could reproduce over 60 percent modeled species within one order of magnitude
when compared with observed molecules at TMC-1 CP.
While for the cyanopolyynes species (HC$_n$N, n = 3, 5, 7, 9),
they are more favored in the opposite condition (with C/O = 1.2) as shown by \citet{Maffucci2018}.
On the other hand, the sulfur element depletion is an unsolved problem \citep{Jenkins2009, Vidal2017, Vastel2018}.
It is known that sulfur remains its ionized atomic form in diffuse and
translucent interstellar medium \citep{Jenkins2009, Laas2019} at an
abundance of its cosmic value, while it is severely depleted in the gas phase of the
dense clouds or cores in almost three orders of magnitude \citep{Agundez2013, Laas2019}.
This problem is raised partially because of the insufficient sulfur chemical reactions in the network,
so that observational values can only be reproduced when the depleted initial elemental sulfur abundance in dense clouds is chosen.
With an update of the sulfur reactions, \citet{Vidal2017} showed that an undepleted elemental sulfur abundance,
which is corresponding to its cosmic value, could also fit the observations in the dense clouds condition.
Thus, a universal value of the initial sulfur elemental abundance is used throughout the simulations range from
different transitional phase of the clouds.
Table \ref{tab.elem} shows the initial elemental abundances.

\begin{table}
\caption{Initial elemental abundances relative to hydrogen nuclei.}
\label{tab.elem}
\begin{tabular}{lc}
\hline \hline
Element     & Abundance  \\
\hline
H$_2$       & 0.5 \\
He          & 9.00(-2) \\
C$^+$$^a$   & 1.2(-4), 1.8(-4), 2.5(-4) \\
O$^b$       & varied \\
N           & 7.60(-5) \\
S$^+$$^c$   & 1.50(-5) \\
Si$^+$      & 8.00(-9) \\
Mg$^+$      & 7.00(-9) \\
Fe$^+$      & 3.00(-9) \\
Na$^+$      & 2.00(-9) \\
Cl$^+$      & 1.00(-9) \\
P$^+$       & 2.00(-10) \\
\hline
\end{tabular}
\\

Notes.\\
a(-b) represents a $\times$ 10$^{-b}$.\\
$^a$ Three different values are tested, see Section \ref{sec.TMC-1CP}.
The low, intermediate and high values are taken from
\citet{Semenov2010}, \citet{Agundez2013} and \citet{Przybilla2018} respectively. \\
$^b$ Calculated with varied C/O ratio range from 0.4 to 1.4. \\
$^c$ Cited from \citet{Vidal2017}. \\
All other values are cited from \citet{Semenov2010}.
\end{table}

\section{Results and analysis}\label{sec.result}
We show the results in this section. We first constrain the initial carbon and oxygen elemental abundances
for the chemical models by comparing the observational molecular abundances at the TMC-1 CP
with our modeled abundances.
The TMC-1 CP is one of the famous targets for many observations.
There are over 90 molecules have been detected at this location.
See \citet{Ohishi1992IAUS, Kaifu2004, Adande2010, Agundez2013, Gratier2016, McGuire2017}
and recent observational references in the previous section.
We divide these molecules into four groups according to their elemental characteristics
and the role they played in the reaction network.
The S group represents all species that include sulfur element.
The N group represents nitrogen-containing species excluding S group species.
The O group represents oxygen-containing species excluding S and N group species.
Finally, the C group represents the remaining species.
They are mainly the hydrocarbons that only include the hydrogen and carbon element.
This group also includes the atomic carbon and diatomic carbon.

\subsection{Chemical variations at the TMC-1 CP emission peak}\label{sec.TMC-1CP}
As introduced previously, the initial carbon to oxygen elemental abundances ratio (C/O)
is important for chemistry in ISM. In this section, we first explore the variations of this ratio on the chemistry.
We keep the initial carbon elemental abundance a fixed value and vary the C/O to derive the initial
oxygen elemental abundance. To explore the variations of the initial carbon abundance, we use three different
values corresponding to low, intermediate and high abundance,
which are 1.2 $\times$ 10$^{-4}$ \citep{Semenov2010}, 1.8 $\times$ 10$^{-4}$ \citep{Agundez2013}
and 2.5 $\times$ 10$^{-4}$ \citep{Przybilla2018} respectively,
while the C/O ratio is varied from 0.4 \citep{Lee1996} to 1.4 \citep{Agundez2013} with a step size of 0.1.
In the following, we show our best fit model results,
followed by a discussion on the chemistry due to the variations of C/O ratio.

\subsubsection{Best fit model}\label{sec.fitmodel}
By comparing the observational abundances of the molecules with the calculations from the models,
we could determine the best fit model and the chemical evolutionary timescale of the molecular cloud.
We use the following Equation \ref{eq.rms}, which is known as the distance of disagreement \citep{Vidal2017},
to calculate the mean logarithmic difference for all detected molecules at every time step.

\begin{equation}
D(t) = \frac{\sum_{i} | log(X_{mod,i}(t)) - log(X_{obs,i}) |}{N_{obs}}
\label{eq.rms}
\end{equation}
where $X_{mod,i}(t)$ and $X_{obs,i}$ is the modeling abundance for species $i$ at time $t$
and observed abundance, respectively, and $N_{obs}$ is the total number of the observed species.

Figure \ref{fig.rms} shows the calculated results for the initial carbon abundance
of 2.5 $\times$ 10$^{-4}$ and a C/O ratio of 0.5. It can be seen that the best fit time
is located at $\sim$5.3 $\times$ 10$^5$ year. This best fit time is in well agreement within
the range of 4.2$\pm$2.4 $\times$ 10$^5$ year estimated from the CO depletion timescale toward
13 cores in Taurus \citep{Pineda2010}.
Moreover, in order to show the diversity of the abundance between observational value and
modeling value of each species, we plot in Figure \ref{fig.TMC1-CP} the logarithmic abundance ratio difference
for each observed species.
In the figure, the left endpoint and right endpoint for each molecule is the minimum and maximum value
in the time range of 10$^4$ to 10$^7$ year respectively. The red cross mark corresponds to the time
at best agreement, i.e.~5.3 $\times$ 10$^5$ year. The vertical grey area between -1 and +1
represent one order of magnitude lower and higher respectively when compared with the observed values.

In Figure \ref{fig.TMC1-CP}, there are 66 out of 93 species,
which is 71 percent whose logarithmic abundance is within the range of -1 to +1 of observation at the best fit time.
This percentage is similar to the results of earlier studies
with a total observed species of $\sim$60 \citep{Agundez2013, Wakelam2015}.
Specifically, for the 23 O group molecules, C$_3$O and CH$_3$O are about two orders of magnitude
overproduced, while the large COMs (CH$_3$CHO, HCOOCH$_3$ and CH$_3$OCH$_3$) are underproduced.
For the 22 C group molecules, there are 8 species out of the range from -1 to +1.
Most of these out-of-range species are C$_n$H$^-$ and C$_n$H$_2$ with n = 4, 6, 8. Note that
all of the small hydrocarbons with fewer than 3 carbon elements are much closer to the observations
than the large hydrocarbons. This trend is also seen in other models, which may indicate that
the inefficient destruction pathways for the larger hydrocarbons when they grow complex.
Nitrogen-bearing molecules in the N group are the most detected species in the TMC-1 CP.
Among them, there are 5 out of 28 that are outside the range from -1 to +1.
They are CN, C$_5$N, H$_2$CN, NH$_2$CHO and HCN,
which are arranged from large to small disagreement with respect to their corresponding observed values.
Comparing with the sequential arrangement for the overproduced small hydrocarbons and large hydrocarbons,
there is no clear such an arrangement for these nitrogen-bearing molecules.

Finally, about a half of S group species (9 out of 20) are outside the range of one order of magnitude
when compared with their observational values at the best fit time.
Among them, CS$^+$ is the most underproduced species, the predicted peak fractional abundance with respect to H
is 2.2 $\times$ 10$^{-11}$ at $\sim$250 year and severely decreased after that.
While the observed abundance of CS$^+$ is 1.5 $\times$ 10$^{-10}$.
As a comparison with CS$^+$, CS is overproduced by two orders of magnitude at its best fit time.
The predicted peak abundance of CS is 1.9 $\times$ 10$^{-6}$ at $\sim$3.9 $\times$ 10$^4$ year and also
decreases after that. While the observed abundance for CS is 1.5 $\times$ 10$^{-9}$.
In the chemical reaction network, CS is mainly produced by HCS$^+$, and destructed by H$^+$ and H$_3$$^+$.
On the other hand, CS$^+$ is mainly produced by reaction of CH with S$^+$, and destructed by electron and H$_2$.
Most calculated abundances of the sulfur-bearing species are larger than their observed values.
The discussion of these discrepancies will be presented later.

\subsubsection{Variation of C/O ratio on the chemistry}
We noticed that the predicted abundances of S group species are closer to their observed values
when the C/O ratio increases. While the trend for other group species is on the opposite.
The variation of C/O on the chemistry as expressed by the numbers of the disagreement species
for the four groups can be seen in Figure \ref{fig.CNOS}, which corresponds to the model with an initial carbon
abundance of 2.5 $\times$ 10$^{-4}$.
The trends for the four groups are also presented for the low and intermediate initial carbon abundance models.
The disagreed species are counted when the logarithmic abundance ratio differences between models and observations
are out of the range from -1 to +1 (see Figure \ref{fig.TMC1-CP}).
Note that the counts are calculated for each model at their own best fit time.

From Figure \ref{fig.CNOS} it can be seen that the C and O group species favor a C/O ratio of 0.5,
and with the increase of the C/O ratio the disagreement rises highly.
As opposed to the C and O groups, S group species favor a C/O ratio larger than 1.2,
while the overall N group species favor a low C/O ratio similar to the C and O groups.
However, the favored low C/O ratio for the overall N group species
seems contradiction with the result of \citet{Maffucci2018}, which shows that a C/O ratio of 1.2
can better reproduce cyanopolyynes. We plot the mean logarithmic abundance difference for cyanopolyynes in Figure
\ref{fig.HCnN} using Equation \ref{eq.rms} with $N_{obs}$ only include
HC$_n$N, where n = 3, 5, 7, 9 at the time determined from the total observed species,
i.e.~the same evolutionary time used in the Figure \ref{fig.CNOS}.
It can be seen that the minimum value is located at C/O = 1.0, which
is close to 1.2, while our best fit model of C/O = 0.5 is in another minimum location.
Generally, as concluded by \citet{Maffucci2018}, the increase of C/O enhances the production of cyanopolyynes.

Chemically speaking, at the carbon-poor, oxygen-rich condition (C/O $<$ 1),
most of carbon are locked with oxygen either in the gas phase or on the grain surface
mainly in the form of CO, CO$_2$, and H$_2$CO.
While at the carbon-rich, oxygen-poor condition (C/O $>$ 1), part of carbon-bearing molecules is hydrogenated,
thus both in the gas phase and on the grain surface, C$_n$H$_m$ and HC$_n$N are overproduced,
where n ranges from 3 to 9, and m = 2, 3, 4.
The initial nitrogen is in the neutral atomic form and less abundant than carbon.
It first reacts with hydrocarbons to form nitriles. Most of species in the N group are nitrile-containing
molecules, thus the chemistry of N group species is also affected by the variation of C/O ratio
and shows similar trend as with the C and O group species.
However, for the subset of HC$_n$N with n = 3, 5, 7, 9 in the N group,
their abundances could be increased by the overproduced large hydrocarbons when C/O $>$ 1,
thus show a better fit with the observations than that at the conditions of C/O $<$ 1.
The effect of the variation of C/O on the chemistry of sulfur-containing species in the S group is more complex
as the elemental compositions of S group species are largely different from each other,
which indicates that the reactions related to S group species are well connected with other group species.
From Figure \ref{fig.CNOS} it can be seen that
the difference between the maximum and minimum counts for S group species is only 2,
which seems not significant when compared with other groups.
There are three species, H$_2$CS, H$_2$S and SO, whose abundances approach to their observed values as C/O increased.
Instead, the abundance of C$_3$S move away from its observed value.
For H$_2$CS and H$_2$S, they share similar production pathways when C/O ratio changes.
However, their destruction involves C$^+$ or C so that they overproduced when C/O $<$ 1.
As for SO, it is produced by the reaction between S and OH, which could be affected by the C/O ratio.
Generally, at C/O $<$ 1, most S group species are slightly overproduced; on the other hand, with the increase of
C/O ratio, the abundances of these species tend to approach their observational values at the best fit time.

\begin{figure}
\includegraphics{rms.eps}
\caption{The mean logarithmic difference for all detected molecules as a function of time
at the TMC-1 CP for the best model with an initial carbon abundance of 2.5 $\times$ 10$^{-4}$ and
a C/O ratio of 0.5.
}
\label{fig.rms}
\end{figure}

\begin{figure}
\includegraphics{gantt_TMC1-CP.ps}
\caption{Model results for all observed molecules at the TMC-1 CP for the best model
with an initial carbon abundance of 2.5 $\times$ 10$^{-4}$ and a C/O ratio of 0.5.
The $x$ axis is the logarithmic abundance ratio difference for each observed molecule.
The left endpoint and right endpoint for each molecule is the minimum and maximum value
in the time range of 10$^4$ year to 10$^7$ year respectively. The red cross mark is the time
at the best agreement, i.e.~5.3 $\times$ 10$^5$ year. The vertical grey area between -1 and +1
represent one order of magnitude lower and higher respectively when compared with its observational value.
}
\label{fig.TMC1-CP}
\end{figure}

\begin{figure}
\includegraphics{CNOS_2.5.eps}
\caption{The number of disagreement species for the four groups as a function of C/O ratio.
The $y$ axis represents the counted disagreement species when the logarithmic abundance ratio
differences between models and observations are out of the range from -1 to +1 (see Figure \ref{fig.TMC1-CP}).
The counts are calculated for each model at its own best fit time.
The S group represents all the species that include sulfur element.
The N group represents all nitrogen-containing species with the excluding of S group species.
The O group represents all oxygen-containing species with the excluding of S and N group species.
The C group represents the remaining species, which includes atomic carbon, diatomic carbon and hydrocarbons.
This figure shows the models with an initial carbon abundance of 2.5 $\times$ 10$^{-4}$.
The trends for the four groups are also seen for the low and intermediate initial carbon abundance models.
}
\label{fig.CNOS}
\end{figure}

\begin{figure}
\includegraphics{rms_HCnN.eps}
\caption{The mean logarithmic abundance difference as a function of C/O only for cyanopolyynes
for the models with an initial carbon abundance of 2.5 $\times$ 10$^{-4}$.
}
\label{fig.HCnN}
\end{figure}

\subsection{Chemical variations along the transitional regions}
In the above section, by comparison between the model results and the observations in TMC-1 CP,
we determined the best initial elemental abundances for carbon and oxygen and the best fit time.
In the following subsections, we show the results of the chemical variations under the predictions
at the best fit time for the transitional regions where A$_V$ ranges from 1 to 20 mag.

\subsubsection{H, H$_2$ and ionization fraction}
As the dominated material, hydrogen is the most abundant element in the ISM both in its atomic form
and in its molecular form. In the initial condition of the models, we assume all hydrogen exists in its
molecular form. Under this condition, all other species are evolved with time. We determine the best
fit time (i.e~5.3 $\times$ 10$^5$ year) for TMC-1 CP
by fitting the abundances of all detected species with their predicted values.
At this time, it can be seen from Figure \ref{fig.H} that the corresponding atomic hydrogen abundance at
A$_V$ $<$ 10 mag is $\sim$10$^{-3}$.
The mean abundance of atomic hydrogen is 10$^{-2.8}$ in TMC and other molecular cloud regions determined by
HI Narrow Self Absorption (HINSA, \citep{Li2003, Krco2010}).
This consistency between predicted and observed HI abundance suggests that the above assumption is reasonable.
If all hydrogen exists in its atomic form at the initial stage, the conversion timescale for hydrogen to its
molecular form could be longer.

The ionization fraction, or the electron abundance ($x(e^-)$), is a basic physical characteristic of the ISM that
has a wide influence on the star formation from the driving of the ion-neutral chemistry
to the dynamics between the gas and magnetic field.
\citet{Goicoechea2009} estimated the gradients of ionization fraction in the Horsehead PDR regions
from the outer edge to the shielded cores where the value changes from 10$^{-4}$ to 10$^{-9}$ respectively.
Unlike the strong UV field in Horsehead PDR regions (35 in habing unit, \citep{Goicoechea2009}),
the UV field in TMC-1 regions is relatively weak (3.8 in habing uint). There has also
a similar ionization fraction gradient (see the right panel in Figure \ref{fig.H}).
At the edge of TMC-1, the value of $x(e^-)$ is $\sim$10$^{-5}$,
which is contributed from C, S and cosmic-ray induced ionization of H$_2$.
In the denser part of TMC-1, the ionization fraction is mainly controlled by the cosmic-ray induced ionization
of H$_2$ because UV photons cannot penetrate into the clouds.

\begin{figure}
\includegraphics[scale=0.8]{H.eps}
\caption{The abundances of HI, H$_2$ and e$^-$ as a function of A$_V$.
In the left panel, HI is shown by empty markers, while H$_2$ is shown by filled markers.
Here and after, we use the three emission peaks to represent the three horizontal lines
that across the TMC-1 filament boundary.
}
\label{fig.H}
\end{figure}

\subsubsection{Carbon, Oxygen and their carriers}
Except for the conversion of atomic hydrogen to molecular hydrogen in the transitional regions,
the species of C$^+$, C and CO are also widely recognized as the evolutionary tracers of
these regions. Figure \ref{fig.CO} shows the calculated abundances of these three species as a function of A$_V$.
It can be seen that the abundance of C$^+$ gradually decreases from the outer low extinction regions
to the inner high extinction regions.
Meanwhile, C$^+$ are partially converted to C and CO, and the abundance of C peaks around $\sim$4 mag.
The conversion of C$^+$ to CO is efficient because of less strength of UV field in these regions and
the shielding from H$_2$ and CO itself.
With the continuing increase of A$_V$, eventually most of carbon are locked in the form of CO.
Meanwhile, at high A$_V$ and density, gas-grain chemistry plays an important role,
and gas phase CO begins to adsorb onto the grain surface.
Thus, we see a depletion of CO after A$_V$ $>$ 10 mag.
The rate of depletion depends on the gas density, with the higher the gas density, the greater the CO depletion rate.
In the horizontal extensions of TMC-1 CP, it can be seen that at the location of offset 3 from the emission peak,
CO is severely depleted, and this position represents the highest density.
The effect of gas density also has an influence on the other gas phase species as can be seen in the following.
Molecules that can be easily synthesized in the gas phase adsorb more quickly onto the grains when the gas density is high;
while for the gas species with low synthesis rate, such as some large molecules,
their abundances trend to be increased under high density conditions.
In comparison, the densities for the horizontal extensions of TMC-1 C and TMC-1 NH$_3$ are generally
decreased from the inner to the outer region.
It should be noted that our results are presented under the same evolutionary times.
Some studies have noticed the possible different evolutionary stages
for the TMC-1 C and TMC-1 CP emission peak \citep{Choi2017, Navarro2021}.
The state of the chemistry could be affected by the different physical conditions and different evolutionary stages of the clouds.
However, it is difficult to decouple the effects of these two factors on the chemistry
as the different evolutionary stages may have implied the different physical conditions,
and it is the focus of our next paper to explore this problem.

The main carriers of oxygen are the atomic oxygen (OI) and CO in the gas phase at A$_V$ $<$ 10 mag.
It can be seen in Figure \ref{fig.CO} that the abundance of atomic oxygen is slightly higher
than that of CO before its depletion.
Recently, \citet{Goldsmith2021} explored the OI emission and absorption in the W3 high-mass star formation regions.
They found that OI is dominated by the foreground absorption of low-excitation atomic oxygen,
and its abundance could be comparable to, or greater than that of CO.
The highest fractional abundance of OI with respect to H is 6 $\times$ 10$^{-5}$ under
an initial oxygen abundance of 2.3 $\times$ 10$^{-4}$ in \citet{Goldsmith2021}.
In our results, the best fit model uses an initial oxygen abundance of 5.0 $\times$ 10$^{-4}$,
and the abundance of OI could be maintained at a level of $\sim$2.0 $\times$ 10$^{-4}$ when A$_V$ $<$ 10 mag.
Thus, the atomic oxygen, along with C and C$^+$, could be used as the chemical tracers to evaluate
the physical properties of the translucent ISM.

\citet{Xu2016a,Xu2016b} also showed that the primary hydrides CH and OH could be used as the
gas tracers across the TMC boundary.
They derived a fractional abundance (with respect to H$_2$) of
$\sim$2 $\times$ 10$^{-8}$ and $\sim$2 $\times$ 10$^{-7}$ for CH and OH at A$_V$ = 2 mag, respectively.
Compared with our modeling results, our predictions for the abundances of CH and OH are underproduced
by a factor of 5 and 30, respectively.
\citet{Xu2016a} interpreted the reason for the large discrepancy between the modeled and observational OH abundance
as the shock, which is originated by the compression of the gas in the cloud's edges.
However, the above estimation is under the assumption that all hydrogen is in the form of H$_2$,
i.e.~the abundance of H$_2$ with respect to the total nuclei is 0.5.
If we assume that a fraction of hydrogen is in the atomic form,
which is reasonable under the cold neutral medium condition,
then the above discrepancy between our predictions and the observations for the abundances of CH and OH
could be replaced by a factor of 25 and 5, respectively, when a value of 0.3
for the abundance of H$_2$ with respect to the total nuclei is used.
It can be seen that the fraction of atomic hydrogen could be important for the primary gas contents
and their chemistry.
Therefore, to better understand the chemistry of CH and OH, direct measurement of primary gas contents,
such as using the HINSA to determine the property of clouds \citep{Zuo2018}, could be helpful.

\begin{figure}
\includegraphics[scale=0.8]{CO.eps}
\caption{The abundances of C$^+$, C and CO as a function of A$_V$.
}
\label{fig.CO}
\end{figure}

\subsubsection{S$^+$, S and main sulfur-containing carriers}
The cosmic value of the sulfur elemental abundance is used so that we could study the
sulfur chemistry across a wide range of A$_V$.
We demonstrate in Figure \ref{fig.S} the calculated most abundant gas phase and grain surface S-bearing molecules.
Similar to the trends of C$^+$ and C as a function of A$_V$, S$^+$ (shown in empty markers) remain its
ionic atomic form when A$_V$ $<$ 3 mag, and are converted to neutral atomic form (shown in filled markers)
at higher A$_V$. When A$_V$ $>$ 10 mag, sulfur is mostly adsorbed onto the grains and
hydrogenated to JHS and JH$_2$S subsequently (hereafter, ``J'' stands for grain surface species)
as shown in the upper panels of Figure \ref{fig.S}. For example, at the TMC-1 CP,
which corresponding to an A$_V$ of 18.2 mag, 59 percent of the total sulfur abundance
is in the form of JHS and JH$_2$S, and 20 percent is occupied by other grain surface species such as
JHSCN, JHSO, JOCS and JNS, whereas 15 percent by the gas phase neutral atomic sulfur,
and the remaining small amount is occupied by other S-bearing species.
For the gas phase S-bearing species, they are mainly produced via the gas phase reactions with the exception
of H$_2$S, which could be produced by the non-thermal desorption of grain surface JH$_2$S.
Among them, CS, SO and SO$_2$ reach their peak abundances when A$_V$ are around or less than 10 mag,
while H$_2$S, CCS and OCS reach their peak abundances in the inner part of the cloud, which
has large A$_V$ and density.
Moreover, it can also be seen in Figure \ref{fig.S} that the abundances of SO and SO$_2$ are more sensitive
to the physical conditions at certain A$_V$, while other species are much less affected.

Compared with other abundant gas phase tracers, such as CO, there is a lack of
abundant S-bearing molecular tracers in the gas phase for the sulfur chemistry.
The abundance of CS reaches 10$^{-6}$ in the hot corino condition \citep{Codella2021},
and depletes to 10$^{-8}$ in the hot core and dark cloud \citep{Luo2019, Bulut2021}.
In Figure \ref{fig.S}, it can be seen that the CS abundance could reach the highest value of 10$^{-6}$ at A$_V$ = 4 mag.
However, the dominant sulfur-carriers above this level are atomic sulfur in the gas phase and JHS and JH$_2$S on the grain surface.
The reason is twofold: the initial elemental S abundance is less than that for C, O and N,
and S is heavier than C, O and N, making it easier to adsorb on the grains.

\begin{figure}
\includegraphics[scale=0.8]{S.eps}
\caption{The abundances of S$^+$, S and other S-bearing species in the gas surface and on the grain surface.
In the top left panel, S$^+$ is shown by empty markers, while S is shown by filled markers.
For JHS and JH$_2$S, the prefix ``J'' stands for grain surface species.
}
\label{fig.S}
\end{figure}

\subsubsection{Nitrogen-bearing molecules}
Figure \ref{fig.N} shows the gas phase N (in empty markers), N$_2$ (in filled markers)
and other nitrogen-bearing species as a function of A$_V$.
The initial nitrogen is in the neutral atomic form due to its slightly higher ionization potential (14.5 eV)
than that of H atom. It can be seen in Figure \ref{fig.N} that the majority of nitrogen remains in its neutral atomic
form when A$_V$ is less than 10 mag, and mostly convert to N$_2$ at higher A$_V$.
N$_2$ is not observable at infrared or millimeter-wavelength transitions, but can be estimated by the
main production channel of N$_2$H$^+$: N$_2$ + H$_{3}^{+}$ $\rightarrow$ H$_2$ + N$_2$H$^+$.
\citet{Womack1992} estimated a gas phase N$_2$ abundance of 4 $\times$ 10$^{-6}$ through N$_2$H$^+$
under the dark cloud conditions, and suggested that gas phase N$_2$ as the dominant nitrogen-bearing species.
In our models, for A$_V$ $>$ 10 mag, the N$_2$ abundances varies between 5 $\times$ 10$^{-6}$ and
1 $\times$ 10$^{-5}$, which is less than 3 times of the observational value.
N$_2$ is mainly produced by the reaction of N + CN $\rightarrow$ C + N$_2$ at earlier time
($\sim$5 $\times$ 10$^4$ year), and by the cosmic-ray desorption of grain surface JN$_2$ at later time.
Two of the destruction pathways of N$_2$ are the reaction of N$_2$ + H$_{3}^{+}$ $\rightarrow$ H$_2$ + N$_2$H$^+$
and the adsorption onto the grain surface.
The production of NH$_3$ is also starting from N$_2$.
Firstly, N$^+$ is produced by the reaction of N$_2$ + He$^+$ $\rightarrow$ N$^+$ + N + He.
Then, following the sequence of N$^+$, NH$^+$, NH$_{2}^{+}$ and NH$_{3}^{+}$ with the
reaction of H$_2$, NH$_{4}^{+}$ is produced.
Finally, NH$_3$ is produced by the reaction of NH$_{4}^{+}$ + e$^-$ $\rightarrow$ H + NH$_3$.
The family of cyanopolyynes, HC$_n$N (n = 3, 5, 7, 9) are produced by the reaction of CN with hydrocarbons
of C$_n$H$_2$ (n = 2, 4, 6, 8).
Overall, except for N$_2$, it can be seen from Figure \ref{fig.N} that the abundances of most nitrogen-bearing
species gradually increase with larger A$_V$ and peak at the highest density.
Generally, the nitrogen-bearing species trace the regions with higher A$_V$ and larger n$_H$.

By comparing the gas phase N$_2$ in Figure \ref{fig.N} with the grain surface JN$_2$ in the following Figure \ref{fig.JH2O},
it can be seen that the trends for N$_2$ and JN$_2$ are very similar, both having a turning point
around A$_V$ of 4--5 mag.
The grain surface JN$_2$ is mainly produced by the grain surface reaction of JN + JNO $\rightarrow$
JO + JN$_2$, and also by the gas phase N$_2$ adsorption. The major consuming channel for JN$_2$ is its cosmic-ray
desorption to the gas phase, which is independent of the A$_V$. Thus, the gas phase N$_2$ and grain surface JN$_2$
are well coupled through the adsorption and desorption mechanism.
By comparing the estimated N$_2$ abundances in the dark clouds and in the warm clouds, which shows no difference,
\citet{Womack1992} suggested that dust grains may not play an important role in the N$_2$ chemistry.
However, according to our above analysis,
we suggest that dust grains indeed could play an important role in the N$_2$ chemistry
by keeping N$_2$ on the grain surface and releasing back to the gas phase at a later time.

\begin{figure}
\includegraphics[scale=0.8]{N2.eps}
\caption{The gas phase abundances of N, N$_2$ and other nitrogen-bearing species as a function of A$_V$.
In the top left panel, N is shown by empty markers, while N$_2$ is shown by filled markers.
}
\label{fig.N}
\end{figure}

\subsubsection{Complex organic molecules}
Complex organic molecules (COMs), which are defined as carbon-containing molecules with at least six atoms \citep{Herbst2009},
represent the advanced complexity during the development of the chemistry.
Some COMs, such as CH$_3$OH and CH$_3$CHO, have been detected
in the diffuse clouds toward Galactic center \citep{Thiel2017} and in the translucent clouds \citep{Turner1998, Turner1999}.
\citet{Thiel2017} estimated the abundances with respect to H$_2$ for CH$_3$OH, CH$_3$CHO and NH$_2$CHO
in the diffuse clouds toward the line-of-sight of Sagittarius B2 of 8.1 $\times$ 10$^{-8}$,
$<$3.2 $\times$ 10$^{-9}$ and $<$8.5 $\times$ 10$^{-10}$, respectively at a $\upsilon_{LSR}$ of 9.4 km/s.
While the fractional abundances with respect to H$_2$ for CH$_3$OH and CH$_3$CHO
in translucent clouds are in the range of 10$^{-9}$ to 10$^{-8}$ \citep{Turner1998, Turner1999}.
However, the origin of these COMs in the diffuse and translucent clouds is still in debate.
\citet{Liszt2018} argued that the nature of the host gas environment could complicate this situation.
Indeed, as suggested in \citet{Thiel2017}, the diffuse clouds chemistry could be enriched
by the mixing between the dense part and diffuse part of the gas.

Figure \ref{fig.COMs} shows the modelled abundances of the three COMs as a function of A$_V$.
At intermediate A$_V$ (around 5 mag), the modeling CH$_3$OH abundance is consistent with the observations,
while CH$_3$CHO and NH$_2$CHO are underproduced.
CH$_3$OH is first synthesized on the grain surface and then desorbed into the gas phase by the chemical process.
The main chemical process for the production of gas phase CH$_3$OH is the chemical desorption of the
exothermic surface reactions. Under a grain temperature of $\sim$10 K, the thermal desorption is not efficient,
and other desorption mechanisms, such as the cosmic-ray desorption, also contribute less
due to the high desorption energy of grain surface methanol.
The origin of gas phase NH$_2$CHO is also in a similar way.
However, CH$_3$CHO is mainly produced by the gas phase reactions of O + C$_3$H$_7$ $\rightarrow$ CH$_3$ + CH$_3$CHO
and O + C$_2$H$_5$ $\rightarrow$ H + CH$_3$CHO.
The destruction pathways for these COMs are mostly by the abundant atomic carbon and by the UV photodissociation.
The high radiation field in the diffuse and translucent environment is one of the reasons
for the low abundances of the COMs. On the one hand, COMs could be dissociated by the high energy photons.
On the other hand, the grain surface chemistry, which is one of the channels that produce the formation of COMs,
could also be suppressed by the high radiation.
Nevertheless, our modeling results show that COMs indeed could be produced
at an abundance of higher than 10$^{-11}$ in the translucent clouds with A$_V$ down to 3 mag.

\begin{figure}
\includegraphics[scale=0.8]{COMs.eps}
\caption{The gas phase abundances of three complex organic molecules as a function of A$_V$.
}
\label{fig.COMs}
\end{figure}

\subsubsection{Variation of grain ice composition}
Water ice is widely present in the dense clouds based on the observations toward the
line-of-sight dense part of clouds toward the background stars \citep{Gibb2000,Gibb2004}.
However, there was no strong evidence for the existence of solid-state water in the
diffuse-dense transition region \citep{Poteet2015}. Recently, \citet{Potapov2020} shows that
water ice could be expected in the diffuse ISM by the laboratory experiments.
Although the mixture of grain ice mantle compositions is hard to determine,
it is interesting to investigate the variation of grain ice compositions under different conditions
for the exploration of grain surface chemistry and the role of gas-grain interactions.
In Figure \ref{fig.JH2O} we show the predicted abundances of grain surface species as a function of A$_V$.
Water ice (JH$_2$O) is the most abundant species when A$_V$ is higher than 4 mag. However, most JH$_2$O are dissociated
by UV photons when A$_V$ is less than 4 mag, thereby making its decrease in the grain ice mantles.
Under this condition, the three most abundant ice compositions are JCO$_2$, JCO and JN$_2$.
Among them, JCO$_2$ are the dominant ice composition at low A$_V$ because of the reaction between JCO and JOH
and between JO and JHOCO, where JOH is provided by the photodissociation of JH$_2$O.
The abundance of JCO has a turning point around 4--5 mag resulting from the competition
between its destruction and formation pathways.
The destruction pathways of JCO are the reactions with JH and JOH,
while the dominant formation pathways of JCO are the UV photon dissociation and cosmic-ray induced UV photon
dissociation of grain surface JCO$_2$. Note that when A$_V$ is less than 5 mag, the contribution of the gas phase
CO adsorption is unimportant. When A$_V$ is smaller than 5 mag, the abundance of JCO
gradually increased because of the increased strength of UV photon and cosmic-ray induced UV photon dissociation of JCO$_2$.
On the contrary, starting from the turning point, with the increase of A$_V$ the effect of photodissociation of JCO$_2$
becomes weaker and gas phase CO adsorption becomes more important, thus leading to the increase of JCO abundance.
After A$_V$ $>$ 10 mag, part of JCO is hydrogenated to produce JHCO, JH$_2$CO and JCH$_3$OH gradually.
It can be seen in Figure \ref{fig.JH2O} that the abundances of JHCO, JH$_2$CO and JCH$_3$OH are more dependent on A$_V$
and reach their highest values at the largest A$_V$ considered in the models.
On the other hand, JH$_2$O, JCO$_2$, JHCOOH, JHCN and JN$_2$ are generally kept constant when A$_V$ is higher than 4 mag.
JHCN and JN$_2$ are produced by the grain surface reaction of JH$_2$ + JCN $\rightarrow$ JH + JHCN and
JN + JNO $\rightarrow$ JO + JN$_2$, respectively. They are both the dominant nitrogen-bearing molecules
on the grain surface.

The grain ice mantle composition depends on many factors, such as the radiation field and n$_H$ density.
We show in Figure \ref{fig.iceLayer} the development of the grain ice mantle layers as a function of time
in four positions at the horizontal line of TMC-1 C and its offset 3, 4 and 5 (see Table \ref{tab.para}).
It can be seen that the ice layers gradually decrease with the decrease of A$_V$.
The ice layers for A$_V$ of 2.2 mag are thicker than that for A$_V$ of 4.8 mag at the time before 10$^5$ year.
This is due to two times higher of n$_H$ density toward the position at A$_V$ of 2.2 mag than
that toward the position at A$_V$ of 4.8 mag.
We list in Table \ref{tab.JH2O} the most abundant fractional ice composition at these positions.
In comparison, we also list the observational values
of the fractional ice comparison toward Elias 16 where the location is in TMC and
the dust-embedded young stellar object W33A \citep{Gibb2000}.
Water ice is the dominated ice composition at the dense part of the clouds.
CO and CO$_2$ ice show comparable fractions in the ice mantles.
Meanwhile, the hydrogenated H$_2$CO, CH$_3$OH, NH$_3$ and CH$_4$ ingredients increased the ice composition complex.
However, in the diffuse-translucent part of the clouds, with the effect of the changes of physical conditions,
such as radiation field and n$_H$ density on the grain ice mantles, the grain ice compositions are greatly altered.
Under these conditions, the CO$_2$ ice becomes the dominant ice composition,
with H$_2$O, N$_2$ and CO ice as the main ingredients.

\begin{figure}
\includegraphics[scale=0.8]{JH2O.eps}
\caption{The abundances of grain surface species as a function of A$_V$.
The prefix ``J'' stands for grain surface species.
}
\label{fig.JH2O}
\end{figure}

\begin{figure}
\includegraphics[scale=0.8]{iceLayer.eps}
\caption{The development of the grain ice mantle layers as a function of time for different A$_V$.
The vertical black line represent the best fit time of 5.3 $\times$ 10$^5$ year.
}
\label{fig.iceLayer}
\end{figure}

\begin{table}
\caption{Fractional ice composition for different A$_V$ and different sources.}
\label{tab.JH2O}
\begin{tabular}{l|cccc|cc}
\hline \hline
            &              & TMC-1 C       &         &           &               &       \\
Species     & 1.63 mag$^a$ & 2.2 mag$^a$   & 4.8 mag & 19.9 mag  & Elias 16$^b$  & W33A$^c$  \\
\hline
JH$_2$O     & 45           & 2             & 100     & 100       & 100           & 100   \\
JCO         & 0 $^d$       & 7             & 1       & 8         & 25            & 8     \\
JCO$_2$     & 100          & 100           & 85      & 11        & 24            & 13    \\
JHCO        & 0            & 0             & 0       & 7         & -$^e$         & -     \\
JH$_2$CO    & 0            & 0             & 0       & 13        & -             & 6     \\
JCH$_3$OH   & 1            & 0             & 2       & 10        & $<$ 3         & 18    \\
JHCOOH      & 5            & 1             & 14      & 5         & -             & 7     \\
JXCN$^f$    & 1            & 2             & 2       & 3         & $<$ 1.5       & 3.5   \\
JNH$_3$     & 0            & 0             & 4       & 4         & $<$ 10        & 15    \\
JCH$_4$     & 0            & 0             & 0       & 1         & -             & 1.5   \\
JHCN        & 0            & 5             & 22      & 6         & -             & -     \\
JN$_2$      & 22           & 11            & 4       & 4         & -             & -     \\
\hline
\end{tabular}
\\

Notes.\\
The prefix ``J'' of a molecule stands for grain surface species. All values are interpreted as percentages.\\
$^a$ Percentages with respect to JCO$_2$ for this column,
while percentages with respect to JH$_2$O for all other columns.\\
$^b$ Cited from \citet{Gibb2004}.\\
$^c$ Cited from \citet{Gibb2000}.\\
$^d$ ``0'' means less than 1 percent.\\
$^e$ ``-'' means undetected.\\
$^f$ The main carrier for JXCN is most probably a cyanate or the OCN$^-$ ion \citep{Gibb2004}. Here we assume
JHOCN as the main carrier for JXCN.
\end{table}

\section{Discussion}\label{sec.discuss}
In this section, we discuss the discrepancy
between the modeling results of large hydrocarbons and sulfur-bearing molecules from their observations.

It can be seen in Figure \ref{fig.TMC1-CP} that the hydrocarbons with the number of carbon fewer than 3 are well
produced, while the large hydrocarbons for the family of C$_n$H$^-$ and C$_n$H$_2$ with n = 4, 6, 8, are overproduced.
The anions are mainly produced by the electron attachment with a neutral species, such as C$_n$H,
and are destructed by hydrogen atom addition.
The two reaction pathways finally lead to the formation of C$_n$H$_2$.
and their rates are rapid under laboratory measurements \citep{Agundez2013}.
It is notable that the abundance of atomic carbon is underproduced by almost two orders of magnitude,
which means that too much carbon is converted to other carbon-bearing species.
The initial donor of carbon is C$^+$, and hydrocarbons grow by the reactions of C$^+$ or C with
C$_{n-1}$H$_2$ or C$_{n-1}$H$_2^{+}$ respectively.
As the result, the overproduced large hydrocarbons may indicate the too efficient conversion processes,
although we cannot rule out the possibility of the inefficient destruction pathways of large hydrocarbons.
In the reaction network, hydrocarbons are mainly dissociated by O or H$_{3}^{+}$, or react with C to form larger hydrocarbons.
There are also charge exchange reactions in the gas phase, but their effect on the decrease of hydrocarbons is minor.
To the best of our knowledge,
the charge exchange reactions of hydrocarbons with grains are not well considered in the network,
thus their effect on the destruction of hydrocarbons is hard to determine.

The sulfur chemistry is another unsolved problem both in terms of observation and astrochemical modeling.
The cosmic value of the sulfur elemental abundance is about 1.5 $\times$ 10$^{-5}$.
While for the commonly detected sulfur-bearing molecules (such as CS, CCS, SO and H$_2$S, etc.)
in dense clouds and other environments, such as diffuse clouds and infrared dark clouds,
their abundances are generally on the level of 10$^{-9}$ or below
\citep{Neufeld2015, Fuente2019, Navarro2020, Xie2021}.
It is also considered that most sulfur could deplete onto the dust grains.
Observationally, the abundances of solid H$_2$S, SO$_2$ and OCS ice with respect to H$_2$O ice
could reach 0.7, 0.8 and 0.04 percent, respectively \citep{Jimenez2011, Boogert1997, Palumbo1995}.
In the dense part of the clouds, our modeling results show that
the dominated carrier for sulfur is atomic sulfur in the gas phase (10$^{-6}$--10$^{-7}$ with respect to hydrogen nuclei)
and solid HS and H$_2$S on the ice mantles (2 percent with respect to water ice).

As presented in Section \ref{sec.fitmodel}, our model could reproduce 71 percent of 93 observed species in TMC-1 CP
where 9 out of 20 sulfur-bearing species are out of one-order-of-magnitude criterion.
\citet{Vidal2017} reproduced a similar percentage with a total observed species of 61
in which 11 sulfur-bearing molecules are included.
To solve the overproduced CS problem, \citet{Bulut2021} considered the reaction
CS + O $\rightarrow$ CO + S with newly theoretical calculated reaction rate. However, their modeling
result for the abundance of CS is still overproduced.
As can be seen in Figure \ref{fig.TMC1-CP}, most overproduced species are carbon-sulfur chains.
In the chemical reaction network, sulfur chemistry is well connected with the hydrocarbons,
such as the reactions with C$_n$H and C$_n$H$_2$ family \citep{Agundez2013}.
This indicates that the overproduced sulfur-bearing species and hydrocarbons may connect with each other.
However, the existence of different types of interstellar dust grains could complicate the situation.
Unlike the silicate dust grain used in our model,
there are also carbonaceous grains and polycyclic aromatic hydrocarbons (PAHs) \citep{Draine2003}.
The destruction of carbonaceous grains could provide an additional source of carbon elements
that may eventually influence the chemistry.
And the inclusion of PAHs in the chemistry has been shown
to improve the agreement with observations for some species \citep{Wakelam2008,Ge2020}.
Further explorations on the puzzling sulfur chemistry and the link between sulfur and hydrocarbons may need
to better understand their formation and destruction pathways in the dark clouds.

Last but not least, as summarized in the Introduction section, the large number of emerged molecules
detected in TMC-1 recently challenged the modeling of astrochemistry.
Due to the lack of most of these new species in the reaction network,
a comprehensive understanding of their evolution is less constrained,
and indeed current simple modeling of their formation tends to underproduce their abundances.
Thus, a systemic census on the formation and destruction pathways for these newly emerged species
will be carried out in the further studies.

\section{Summary}\label{sec.conc}
In this paper, we investigated the chemical variations across the TMC-1 filament from the outer
regions to the innermost regions, which represent the transitions from the translucent phase
to the dense phase as indicated by the extinction. Three horizontal lines were chosen starting
from three emission peaks, which are the cyanopolyynes emission peak (TMC-1 CP), the ammonia
emission peak (TMC-1 NH$_3$) and the dust continuum peak (TMC-1 C). Their physical parameters were
extracted from \citet{Fuente2019}, which were used to constrain the physical conditions of our
studied regions. Among them, TMC-1 CP is the frequently observational target in the literature
where more than 90 molecules have been identified.
We divided the identified molecules into four groups by the representative species, which are C group
(hydrocarbons), S group (all the sulfur-containing molecules), N group (nitrile-containing molecules)
and O group (the remaining oxygen-containing molecules).
Under the above conditions, we first constrained our key chemical parameter,
(i.e.~the initial elemental abundances of carbon and oxygen) by comparison between the observational
molecular abundances and the predicted modeling abundances, and determined the evolutionary chemical
timescale of TMC-1 CP.
We then studied the chemical variations of different groups of molecules as a function of extinction,
and investigated the most common and abundant grain ice mantle compositions.
These results could serve as the template for the study of the transitional regions from
the translucent phase to the dense phase of the molecular clouds.
Finally, we presented and analyzed the chemical evolutions of the tracers in these regions,
especially for the grain surface species that show a distinct difference between the translucent phase and the dense phase.

Our model results can be compared with the observational results from \citet{Fuente2019}.
The trends of the chemical abundances as a function of A$_V$ for species CO, CS and SO are successfully reproduced.
While for N$_2$H$^+$, the comparison reaches agreement when A$_V$ $>$ 10 mag.
\citet{Xu2016b} studied the CH across the edge of the TMC where A$_V$ $<$ 2 mag,
and showed that its abundance keeps nearly constant across that region.
Our model shows that the abundance of CH also keeps nearly constant when A$_V$ $>$ 2 mag.
We conclude that the chemical model is a suitable tool to explore the physicochemical conditions of the clouds.
We have presented several other species for the four groups,
which could be useful for future studies of the transitional regions,
such as the edge of a molecular cloud or the region from the envelope to the inner part of a dense core.
For the ice mantle species, the future observations of James Webb Space Telescope (JWST)
could be essential for the identifications of these grain ice mantle compositions.

We summarize the main conclusions as follows:
\begin{enumerate}[1.]
\item Our best fit model for TMC-1 CP could fit 71 percent observed molecules within one order of magnitude,
and shows that the evolutionary time of TMC-1 CP is $\sim$5.3 $\times$ 10$^5$ years,
which is consistent with the CO depletion timescale found in the molecular cores located
in the TMC-1 (Figure \ref{fig.rms}, Figure \ref{fig.TMC1-CP}).

\item The variation of initial carbon to oxygen elemental abundance ratio (C/O) has different impact
on different group of molecules. Specifically, C and O group molecules favor a low C/O condition (C/O = 0.5),
while S group molecules seem to favor a high C/O condition.
N group molecules are also affected by the variation of C/O.
Although cyanopolyynes (HC$_n$N, where n = 3, 5, 7, 9) favor the condition at C/O = 1.0,
the overall N group molecules could best fit by a low C/O of 0.5 (Figure \ref{fig.CNOS}, Figure \ref{fig.HCnN}).

\item As the molecular cloud evolves from the translucent phase to dense phase, there is a conversion process for
carbon-, oxygen-, nitrogen- and sulfur-bearing species, i.e.~from the atomic form to their main reservoir form.
However, the dominated converted form depends on the elements.
Atomic carbon and oxygen first convert to CO when A$_V$ $\approx$ 2 mag (Figure \ref{fig.CO}).
When A$_V$ $\approx$ 3--4 mag, ionic atomic sulfur converts to neutral atomic sulfur, which is the main gas phase reservoir.
Sulfur could also be depleted onto grain surface to form JHS and JH$_2$S (``J'' stands for grain surface species)
when A$_V$ is larger than 10 mag (Figure \ref{fig.S}).
The conversion of atomic nitrogen to N$_2$ begins when A$_V$ is larger than 10 mag (Figure \ref{fig.N}).

\item COMs, such as CH$_3$OH, CH$_3$CHO and NH$_2$CHO,
could also exist in the translucent gas for A$_V$ down to 3 mag (Figure \ref{fig.COMs}).
The main chemical mechanism for the production of CH$_3$OH and NH$_2$CHO is the chemical desorption of
the grain surface reactions. While for CH$_3$CHO, it is directly produced in the gas phase.

\item Grain ice mantle composition has a dependence on A$_V$.
H$_2$O ice is the dominant ice composition at A$_V$ $>$ 4 mag.
CO ice is severely decreased around A$_V$ of 4--5 mag.
The composition of CO$_2$ ice keeps nearly constant at A$_V$ $>$ 4 mag
and is the dominant component when A$_V$ $<$ 4 mag.
N$_2$ ice tends to enrichment at low extinction condition
(Figure \ref{fig.JH2O}, Table \ref{tab.JH2O}).

\end{enumerate}

\acknowledgments
We thank the reviewer's helpful comments on improving the manuscript.
This work is supported by the National Natural Science Foundation of China (NSFC) grant No.~11988101 and No.~11725313.
D.Q.~acknowledges supports from the NSFC grant No.~11973075.
X.H.Li acknowledges the Xinjiang Tianchi project (2019).
L.X.~acknowledges supports from the science and technology projects in Jilin Province Department of Education grant JJKH20200607KJ,
and from the NSFC grant No.~11703075, CAS "Light of West China" Program 2017-XBQNXZ-B-020
and the Heaven Lake Hundred-Talent Program of Xinjiang Uygur Autonomous Region of China.

\bibliographystyle{aasjournal}

redpajama_set_name: RedPajamaArXiv