text:
Emails show SF zookeepers pushed for extra help, warned of hazards before gorilla death
Nov. 15, 2014 12:00 a.m.
Courtesy of the San Francisco ZooSan Francisco Zoo officials say the zoo's six surviving gorillas
More than a year before a closing hydraulic door fatally crushed a 16-month-old gorilla, zookeepers pushed for extra staff to monitor the San Francisco Zoo's youngest gorilla and warned that young gorillas had trouble understanding the zoo's electric doors, documents show.
National agencies and an investigator hired by the zoo are trying to piece together what happened Nov. 7 when Kabibe, a western lowland gorilla who was born at the zoo in July 2013, somehow ended up pinned underneath one of the doors to the gorillas' nighttime enclosure at closing time.
Initial information released by the zoo shows that the zookeeper "appeared" to not follow protocol by keeping a hand on an emergency stop button to the doors as they closed.
Emails and documents obtained by The San Francisco Examiner on Friday show that gorilla keepers warned that young gorillas did not understand closing doors, and that after Kabibe was introduced to the group, workers pushed for a third zookeeper who was never hired.
The zoo was in negotiations with the Teamsters union, which represents the zookeepers, to institute a "buddy system" when dealing with "code red" animals, according to documents. A "code red" animal is an animal with the ability to kill a human, such as a bear, tiger or gorilla.
"The only long term, safe, and feasible option I can think of is adding another "Ape Keeper" to our staff who will assist both Chimps and Gorillas," an unidentified zookeeper wrote in an email that included a detailed proposal and schedule for the "ape keeper."
Zookeepers proposed having the "ape keeper" assist with the process of herding the gorillas into their secured quarters for the night.
"This third person is necessary due to the increased workload from the introduction of an infant gorilla to the group and the preparation needed for the chimpanzee move," according to the proposal.
A zoo spokeswoman did not immediately respond to a request for comment Friday.
Further, problems with the electric doors specific to young gorillas like Kabibe were identified as early as 2010.
Hasani, another member of the gorilla herd – who at that time was roughly the same age as Kabibe when she died – "does not understand closing doors," a zookeeper wrote in a Jan. 28, 2010 memo obtained by The San Francisco Examiner. "Avoid shifting Hasani into far-off electric doors (which are hard to see gorillas through) as much as possible."
The zoo has hired Dr. Terry Maple, a renowned zoo expert and former head of the Association of Zoos and Aquariums, to investigate Kabibe's death. The association will also conduct its own inquiry.
Maple told other media this week that the gorilla enclosure ought to be redesigned, in part because of wire mesh that reduces visibility for the zookeepers.
After the fatal mauling of a zoo guest by a tiger who escaped from her enclosure on Christmas Day 2007, the zoo has enjoyed soaring revenue and visitor numbers.
The zoo also passed its last two accreditation inspections, from the Association of Zoos and Aquariums in 2010, and from the U.S. Department of Agriculture in January of this year.
Though the association review found "several large holes in the wall" near keeper access in chimpanzee holding, no issue with the gorilla enclosure was identified by either agency, according to records.Bay Area Newsgorilla deathKabibeSan Francisco zoo
Man injured in shooting near Candlestick Park
Pedestrian seriously injured in crash in Potrero Hill


Seems an interesting story, I wonder how isolated the "jungle" really was?
That is a fabulous story, Ed.
It was the "State Entry" part of Platform 1 at New Delhi Station. That was where the Viceroy, the Governor General and then the President boarded their special train. It was last used by S.Radhakrishnan when he left office in 1967. Sion after that the Begum moved in as Delhi's most eminent squatter.
Stubborness, snobbery, what the Americans call "entitlement," etc etc.
Surely our prince had an education? He could have gone out to work or business and made some comfort in at least a corner of that amazing place.
And yes, I've met a royal or two. Whilst they may have great wealth in the form of property, they also work for a living. And they are also not champion snobs.
And if he was loney, whose fault is that? like Google Maps says: 700 metres from the rest of Delhi.
On the other hand, if he chose to live as a recluse in a crumbling palace, he had the palace, so yes, he was entitled to do so. I could go for that!
Still a tragic life and death.
An older article about the royal family.
"The House of Oudh does not appreciate trade, business and politics," said the prince. "It is better to be in the grip of death rather than in the grip of a job."
As per one of the article he seems to have given an interview in 1997. I am searching for it. If I get it would mention it here.
" "It is better to be in the grip of death rather than in the grip of a job."
Haha, it has sometimes seemed to me that it might be better to be in the grip of death rather than the grip of a job!
Sympathy and words like tragedy seem completely out of place for these people. They did what they chose to do, and it looks as if they were not particularly nice about it. There are lots of people like this, both with and without actual cash. The ones without cash are not often lucky enough to be given a palace, in any condition, in which to live out their fantasy of being superior people.
Seems to me he was pretty dammed lucky. And if his family spent their wealth on high living, that isn't anybody else's problem.
I think it is the eccentricity of these people that interests me. Mind you, only certain people can be eccentric... Poor eccentrics are just mad, sadly!
While the prince was decaying in his false sense of grandeur, future generations of his servants were busy creating a thriving business off their knowledge.
"he would talk about terrible sorrows his family had endured and all the injustices they had suffered over the years."
"his unshakable belief in his own nobility prevented him from mixing with anyone he regarded as a social inferior"
"Ordinariness is not just a crime, it is a sin"
Sounds like an entitled teenager to me. The world seems to exist to punish these.


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If a Stafford Loan is unable to cover all of your expenses, you should research other loan options that are available to you. This includes federal loans, institutional loans and private loans. It's best to speak with a financial advisor to explore your options and help you make a decision.


text:
Q: Anchor can't find headings I have headings in all of my TFS 2018 Wiki documentation but I can't seem to link to those headings. If I have a document at /foo/bar and a heading in the bar document called # 1.3 Hello World I would expect my link to be [Hello World](/foo/bar#1.3-Hello-World) but when I click on that link it doesn't take me to the heading. Instead, it just takes me to the document itself.
When I look at the URL, it shows &anchor=1.3-Hello-World but that anchor is not scrolled to. In this example, I have to scroll pretty far in order to find the heading. How can I link directly to a heading in TFS 2018 Wiki markdown?

A: I don't believe anchor links are supported in TFS 2018 Wiki. I can't get it to work and I find no evidence it is (presently) supported.
Much or all of the material cited here refers to a different product, Visual Studio Team Services (VSTS) Wiki. Follow a link and notice the somewhat obscure top, left-hand (product) drop down list (Visual Studio Team Services). Change it to TFS 2018 and notice that the reference material (documentation) changes.
TFS 2018 tends to be a bit behind the hosted VSTS product. I would not be surprised support is coming in a future release.

A:
Once the Wiki Git repository is provisioned for your team
  project, a new page opens in which you can specify a title and add
  content. This is a side by side edit and preview experience that will
  allow you to edit the page and preview the content as you type.
You author pages using markdown format. Also, you can use the
  format pane for rich-text formatting and to insert images,
  attachments, and links.

WiKi is also using markdown format, details please refer: Syntax guidance for Markdown files, widgets, wikis, and pull request comments
About the Link part please take a look at below format:
Supported links for Wiki:

*

*Absolute path of Wiki pages: [text to
display](/parent-page/child-page)

*URL: [text to display](http://address.com)
Anchor links
Within Markdown files, anchor IDs are assigned to all headings when rendered as HTML. The ID is the heading text, with the spaces replaced by dashes (-) and all lower case. In general, the following conventions:

*

*Punctuation marks and leading white spaces within a file name are
ignored

*Upper case letters are converted to lower

*Spaces between letters are converted to dashes (-).

More details please refer Anchor links

redpajama_set_name: RedPajamaStackExchange


So, Christmas doesn't exactly have to be a storm, but for most of us it is! It's a busy storm that keeps us out and about spending time, money, and energy in places out of routine, and away from our everyday lives. The holiday season includes fun, misery, memories, a lot of stress, and did I mention more memories?!
So, here are my 5 tips to get you through the next couple of days.
You don't have to go out and log half marathon miles or put in 2 hours at the gym. But, you do need to do something physical for yourself! Getting out and walking is a great stress release. Walk in between meals over the holidays, or when there is some down time between activities. The fresh air will revitalize your soul, and give you a fresh outlook. Bring the kids too! Its never too soon to get them involved in physical activity.
Pick up a last minute class at the gym. I got in my yoga class this AM, YAY! If you cant make it to a class or gym, get in a good 30 minute workout at home or yoga series. You can even workout with the TV! Point is, exercise isn't to make room for all the food you plan to eat (even though it helps), its to help clear your mind!
Keep yourself on track and organized by making "To Do" lists. This helps keep your goals and activities you need to accomplish right in front of your face so you don't let something slip by in all the hustle and bustle.
So, I know, 'Tis the Season to imbibe, but keep it to a minimum. Drink a glass of water for every alcoholic beverage to keep your body hydrated.
***Never drink and drive...Uber...taxi...call a friend...stay where you are....please remember to not get on the road and behind the wheel!
Try to get enough sleep so you stay fresh and relaxed. Plan ahead and follow Tip 2 to help you with getting enough rest!
Smile, and smile some more! Its about making memories with family and friends. Try to find the best in your situation and enjoy the holidays! Every year is a gift you have to be around your family and friends, even the one's that get on your last nerve!
We hope you have the Hap Happiest Holiday Season this side of the Nut House! Cheers!


text:
Payment MyPortal Blackboard
Governance Structures
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Students Cards
Databases and eResources
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Faculty Staff – Who's Who
Dr Robert Andrews
BA (Hons) (UNDA, 2007), PhD (Murdoch, 2012)
RAndrews@cis.catholic.edu.au
Doctor of Philosophy, Murdoch University (2012)
Bachelor of Arts (Honours), University of Notre Dame, Australia (2007)
Areas of Research Interest
English Catholicism and Anglicanism in the eighteenth and nineteenth centuries
The life and thought of John Henry Newman
Australian Catholic history
Born in Sydney, raised in Hobart and educated in Perth, I have been employed at the Catholic Institute of Sydney since 2016. Prior to working at CIS I taught at various places in Perth, including the University of Notre Dame Australia in Fremantle. I received my PhD in Church History at Murdoch University in 2012, under the supervision of Professor Rowan Strong. In addition to being Senior Lecturer in Church History at CIS, I also hold the role of Assistant Dean (Academic). I maintain a keen interest in various areas of historical scholarship related to the discipline of Church history, especially the religious aspects of nineteenth-century Britain and, in particular, the life and thought of John Henry Newman (1801–90). I am a member of various professional bodies, including the Ecclesiastical History Society of Great Britain. I am also a member of and councillor for the Australian Catholic Historical Society. In late 2022, I was elected a Fellow of the Royal Historical Society.
"Nicholas Wiseman, The Dublin Review, and the Oxford Movement: A Study with Reference to John Henry Newman, 1836 to 1845." Church History 91, no. 2 (2022): 332–59.
"Continuing Anglicanism? The History, Theology, and Contexts of 'The Affirmation of St Louis' (1977)." Journal of Religious History 46, no. 1 (2022): 40–60.
"The Spirit of Anglicanorum Coetibus: Beauty in the Development of Anglican Patrimony." In The Anglican Patrimony in Catholic Communion: The Gift of the Ordinariates, edited by Tracey Rowland, 109–30. London: T&T Clark, 2021.
Apologia Pro Beata Maria Virgine: John Henry Newman's Defence of the Virgin Mary in Catholic Doctrine and Piety. Washington, DC: Academica Press, 2017.
"High Church Anglicanism in the Nineteenth Century." In Oxford History of Anglicanism, Vol. 3: Partisan Anglicanism and its Global Expansion, 1829–c.1914, edited by Rowan Strong, 141–64. Oxford: Oxford University Press, 2017.
"Luther's Reformation and Sixteenth-Century Catholic Reform: Broadening a Traditional Narrative." Australasian Catholic Record 94, no. 4 (2017): 427–39.
"Joshua Watson: High Church Lay Activism and the Development of Colonial Anglicanism, 1814–1855." International Bulletin of Mission Research 40, no. 4 (2016): 358–67.
"The 'Miasma of Myth': John Henry Newman, the Oxford Movement, and the Hagiography of a Romantic Hero." Colloquium 48, no. 2 (2016): 209–22.
Lay Activism and the High Church Movement of the Late Eighteenth Century: The Life and Thought of William Stevens, 1732–1807. Leiden: Brill, 2015.
"Women of the Seventeenth and Eighteenth-Century High Church Tradition: A Biographical and Historiographical Exploration of a Forgotten Phenomenon in Anglican History." Anglican and Episcopal History 84, no.1 (2015): 49–64.
"Does Devotion to Our Lady Ever go too Far? Newman on Marian piety in the Letter to Pusey(1866)." The Downside Review 130, no. 460 (2012): 43–60.
"'Our Pattern of Faith': The Virgin Mary in John Henry Newman's Theory of Religious Development." Compass: A Review of Topical Theology 46, no. 3 (2012): 27–37.
"'Master in the Art of Holy Living': The Sanctity of William Stevens." In Saints and Sanctity, edited by Peter Clarke and Tony Claydon, 307–17. Woodbridge, UK: Boydell Press, 2011.
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Kombucha Tea is a very ancient Folk Drink. Simply fermented sugar and tea. Originally relying on natural airborne yeast and bacteria, creating a low alcohol (less than 1%), semi-sweet, semi-sour, slightly carbonated, health beverage.
Similar to "Lambic Beer", with 2 major differences. Kombucha is brewed aerobically (open to the air) and simultaneously with the Acetobacter species of bacteria. This species converts the alcohol made by the yeasts into the beneficial acids that makes Kombucha Tea so wonderfully tasteful and healthy.
This section is dedicated to those who want the wonderful health benefits of Kombucha - with a little more kick.


text:
Terrestrial radioactivity
Radioactivity source of life
Automatic translation Category: matter and particles
Radioactivity is a natural phenomenon ionizing present everywhere, which occurs in the nucleus, in the depths of the atoms. Unstable radioactive elements of the earth radiate much energy per disintegration.
Disintegration is the transformation of matter which naturally ejects particles and produces radioactive neutron radiation and energy. Uranium, thorium and potassium are the main radioactive elements responsible for the heat of the Earth. Although terrestrial radioactivity steadily decreased because radioactive atoms become stable elements, it remain still very important because uranium 238, thorium-232 and potassium 40 are long-lived elements (several billion years). Other radioactive elements those which have a very short period relative to the age of the Earth disappeared. And since its formation there is 4.2 billion years, the Earth gradually loses its intrinsic heat and cools down.
Earth drains continuously, a total power of ≈ 44 terawatts equivalent of 44,000 nuclear reactors. What is remarkable about observing our solar system, is the extraordinary diversity of objects connected to it. Yet they are all formed from the same cloud at the same place in the universe, from the same materials at the same time there are about 5 billion years.
How objects have been able to evolve so differently from identical initial conditions?
Astrophysicists have long sought to understand this phenomenon. And the most amazing is that an object has been able to create the conditions for the emergence of life and to have them preserved until today. If Astrophysics explains quite well the evolution of stars, it is far to explain the evolution of planets.
What are the conditions that led to the Earth so much complexity?
Is this the most complex object in the universe?
How planets absorbed energies so different?
From the same initial state, all objects over time will evolve differently, they will gradually acquire an internal energy and will slowly lose it, depending of their mass. Indeed, the size of the object has a major importance in the accumulation of internal energy, astronomical objects are like energy tanks which empty gradually as the radioactive decay of its elements. The main active planets engine is the internal radioactivity which is converted into heat which rises from the center to the surface and maintains a certain activity (magnetism, volcanism, continental drift, recycle the atmosphere,...) on the planet.
The enormous solar energy is not sufficient to maintain our planet active because this energy is blocked at the earth's surface and does not penetrate the center of the Earth. The energy which do that the Earth is alive is trapped inside the planet, it is that of the radioactivity of uranium, thorium and potassium. If there was no radioactive decay, the Earth would be a dead planet. In summary, more the tank is bigger and more it will store energy. When the object is large it cools slowly. Thus small asteroids and comets have frozen there 5 billion years, the large asteroids have frozen there 4 billion years, the Moon has frozen there 3 billion years, Mars has frozen there to 1 billion years, the Earth after 4.2 billion years ago is still an active planet. More solar system objects are small (asteroids, comets) and more they interest to scientists because they spread all their energy into space and kept intact the materials at the time of their "dead", in particular organic molecules.
nota: natural radioisotopes: Americium 241, antimony 125, carbon-14, cesium-134, 135 and 137, chlorine-36, cobalt-60, curium 242 and 244, iodine-129, 131 and 133, krypton-85 and 89, phosphorus-32, plutonium-239 and 241, polonium-210, potassium-40, radium 226 and 242, ruthenium-106, selenium-75, sulfur-35, strontium-90, thorium-234, tritium 3, uranium 235 and 238.
Image: The Earth is a huge reservoir of energy. This energy depths up to the surface by convection. The heat released by the natural radioactivity of deep rocks as uranium, thorium and potassium maintains a mild temperature on the surface since 4 billion years. The different layers of the Earth's are crust solid on the surface which has a thickness of 30-65 km, the upper mantle viscosity of 670 km, the lower elastic mantle of 2180 km, the liquid outer core 2270 km and the solid inner core 1220 km.
Antimatter and antiparticle... What is an electric charge?... The valley of stability of atomic nuclei... Quantum computers... E=mc2 explains
the mass of the proton... Fields of the real...
12 particles of matter... The atomic orbital
or image atom... Abundance of chemical
elements... Superpositions of quantum states... Mystery of matter,
where does its mass? Quantum tunneling of
quantum mechanics...
The quark confinement ... Radioactivity, natural
and artificial... Size of atoms...
Principle of atomic absorption... Alpha decay... What is a wave?
Scale of the nanoparticles...
of elements...


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Step 3: LED (red light) line status: slow flashing – line ringing/fast flashing – line busy.
Step 1: Lift the phone receiver.
Step 3: Dial 7-1-1 or the TRS TTY direct telephone number.
Step 4: When the screen says "call answered" dial ***.
Step 5: Wait for the display screen to say "<TYPE MESSAGE HERE>," then tyupe your message using the keyboard.
Step 6: When you have completed your call, hang up the phone receiver.
Step 3: When prompted, enter the destination number (10 digit number of the device you want to send the message to).
Step 4: When you have entered the destination number, enter *9 to move to the next screen.
Step 5: Enter your message, when complete, send your message using *9.
Also see 'Yellow Pages' for Rehabilitation services.
Vocational Rehabilitation & Services for the Blind.
Please contact your child's school for special education assessment and services. School personnel will direct you and your child to the appropriate special education resources. For further assistance, you can call the Complex Area Superintendent at 274-3502; Special Education at 274-3504; Guidane Health Special Services at 274-3504.


Create the perfect Christmas gift this year with our card holder; personalised with your own words and names.
In ADD PERSONALISATION, please write the names and/or message of your choice that you would like to be custom engraved into your keepsake piece. Please leave as much description as possible.


A member of The Irish Hotels Federation (IHF), Michael Rosney, has welcomed the recent sale of the four star Parknasilla Hotel in Sneem near Killarney for a figure reported to be around €10m, as well as the impending sale of the five star Sheen Falls Lodge in Kenmare for some €5m. Mr Rosney said that these hotel sales showed that, at last, there appears to be some "movement in the industry" after almost five years of decline and stagnation.
Last month a leading Killarney hotel owner and industrialist, Dr Isolde Liebherr, formally received the gratitude of the local Killarney business community for her company's valuable contribution to the local economy. Dr Liebherr was inducted into the Order of Innisfallen which recognises individuals who make a unique contribution to the Killarney area. She was a also a special guest of the Kerry branch of the Irish Hotels Federation at its annual ball in the Europe Hotel where she was presented with a portrait by Dublin artist Paul Kelly that was commissioned by the local Killarney business community.
Dr Liebherr is vice-president of the Liebherr Group, a German company that owns three hotels in the Killarney area that together employ some 275 people. Liebherr's Irish hotel operation, Killarney Hotels Ltd, owns the five star Europe Hotel & Resort as well as The Dunloe and Ard na Sidhe Country House.
The Malton hotel in Killarney recently received an accolade at an award ceremony held by the Golfers Guide to Ireland in Dublin. The ceremony held at the end of January in O'Connell's Restaurant in Donneybrook also celebrated the launch of the 2012 edition of the well-known golf guide book. Published by Portside Publications, The Golfers Guide is the longest established golf guide in Ireland. The publisher is an Irish company that has operated for over 21 years in the tourism sector.
What a remarkable few months for Irish golf. In June Rory McIlroy won the US Open at the Congressional Country Club in Maryland and Darren Clarke has just lifted the famous Claret Jug at Royal St George's at Sandwich in Kent. Two Irish players are currently the hottest property in the golfing world and their unprecedented success is sure to make some kind of golf mania take a grip on the whole county.


text:
Q: TensorFlow CNN loss quickly increases to NaN I'm trying to train a regressor model that can predict 4 scalar float outputs. As it currently stands, the network very quickly diverges with loss increasing to NaN. I can't figure out what's going on.
Below is a self-contined sample tested with TensorFlow 1.1.0 on Windows 10 with a NVidia GPU.
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import numpy
import tensorflow as tf

IMAGE_HEIGHT = 320
IMAGE_WIDTH = 160
NUM_CHANNELS = 3

PIXEL_DEPTH = 255
SEED = 66479  # Set to None for random seed.
BATCH_SIZE=5
NUM_OUTPUTS = 4 # the four outputs

def data_type():
    return tf.float32

# The variables below hold all the trainable weights. They are passed an
# initial value which will be assigned when we call:
# {tf.global_variables_initializer().run()}
conv1_weights = tf.Variable(
  tf.truncated_normal([5, 5, NUM_CHANNELS, 32],  # 5x5 filter, depth 32.
                      stddev=0.1,
                      seed=SEED, dtype=data_type()))
conv1_biases = tf.Variable(tf.zeros([32], dtype=data_type()))
conv2_weights = tf.Variable(tf.truncated_normal(
  [5, 5, 32, 64], stddev=0.1,
  seed=SEED, dtype=data_type()))
conv2_biases = tf.Variable(tf.constant(0.1, shape=[64], dtype=data_type()))
fc1_weights = tf.Variable(  # fully connected, depth 512.
  tf.truncated_normal([IMAGE_HEIGHT // 4 * IMAGE_WIDTH // 4 * 64, 512],
                      stddev=0.1,
                      seed=SEED,
                      dtype=data_type()))
fc1_biases = tf.Variable(tf.constant(0.1, shape=[512], dtype=data_type()))
fc2_weights = tf.Variable(tf.truncated_normal([512, NUM_OUTPUTS],
                                            stddev=0.1,
                                            seed=SEED,
                                            dtype=data_type()))
fc2_biases = tf.Variable(tf.constant(
  0.1, shape=[NUM_OUTPUTS], dtype=data_type()))

  # We will replicate the model structure for the training subgraph, as well
  # as the evaluation subgraphs, while sharing the trainable parameters.
def model(data, train=False):
    """The Model definition."""
    # 2D convolution, with 'SAME' padding (i.e. the output feature map has
    # the same size as the input). Note that {strides} is a 4D array whose
    # shape matches the data layout: [image index, y, x, depth].
    conv = tf.nn.conv2d(data,
                        conv1_weights,
                        strides=[1, 1, 1, 1],
                        padding='SAME')
    # Bias and rectified linear non-linearity.
    relu = tf.nn.relu(tf.nn.bias_add(conv, conv1_biases))
    # Max pooling. The kernel size spec {ksize} also follows the layout of
    # the data. Here we have a pooling window of 2, and a stride of 2.
    pool = tf.nn.max_pool(relu,
                          ksize=[1, 2, 2, 1],
                          strides=[1, 2, 2, 1],
                          padding='SAME')
    conv = tf.nn.conv2d(pool,
                        conv2_weights,
                        strides=[1, 1, 1, 1],
                        padding='SAME')
    relu = tf.nn.relu(tf.nn.bias_add(conv, conv2_biases))
    pool = tf.nn.max_pool(relu,
                          ksize=[1, 2, 2, 1],
                          strides=[1, 2, 2, 1],
                          padding='SAME')
    # Reshape the feature map cuboid into a 2D matrix to feed it to the
    # fully connected layers.
    pool_shape = pool.get_shape().as_list()
    reshape = tf.reshape(
        pool,
        [pool_shape[0], pool_shape[1] * pool_shape[2] * pool_shape[3]])
    # Fully connected layer. Note that the '+' operation automatically
    # broadcasts the biases.
    hidden = tf.nn.relu(tf.matmul(reshape, fc1_weights) + fc1_biases)
    # Add a 50% dropout during training only. Dropout also scales
    # activations such that no rescaling is needed at evaluation time.
    if train:
      hidden = tf.nn.dropout(hidden, 0.5, seed=SEED)
    return tf.matmul(hidden, fc2_weights) + fc2_biases

def main():

    train_data_batch = tf.placeholder(tf.float32, shape=(BATCH_SIZE, IMAGE_HEIGHT, IMAGE_WIDTH, NUM_CHANNELS))
    train_label_batch = tf.placeholder(tf.float32, shape=(BATCH_SIZE, NUM_OUTPUTS))

    with tf.name_scope('pred'):
        train_pred = model(train_data_batch, train=True)

    with tf.name_scope('loss'):
        loss = tf.reduce_sum(tf.square(train_pred - train_label_batch))
        tf.summary.scalar('loss', loss)

    # L2 regularization for the fully connected parameters.
    regularizers = (tf.nn.l2_loss(fc1_weights) + tf.nn.l2_loss(fc1_biases) +
                  tf.nn.l2_loss(fc2_weights) + tf.nn.l2_loss(fc2_biases))
    # Add the regularization term to the loss.
    loss += 5e-4 * regularizers

    optimizer = tf.train.GradientDescentOptimizer(0.01)
    train_op = optimizer.minimize(loss)

    with tf.Session()  as sess:
        # The op for initializing the variables.
        init_op = tf.group(tf.global_variables_initializer(),
                           tf.local_variables_initializer())

        sess.run(init_op)

        while True:
            predictions, l, _ = sess.run([train_pred, loss, train_op], feed_dict={

                train_data_batch: numpy.zeros([BATCH_SIZE, IMAGE_HEIGHT, IMAGE_WIDTH, NUM_CHANNELS])+0.2,
                train_label_batch: numpy.zeros([BATCH_SIZE, 4])})

            print(l)

if __name__ == "__main__":
    main()

output:
9031.0
5.6838e+22
nan
nan
nan
nan
nan
nan
nan
nan
nan
nan
nan
nan
nan

A: It appears that my model was diverging. I solved this by changing to an AdamOptimizer:
optimizer = tf.train.AdamOptimizer(0.5)

This adaptively sets parameters for a momentum optimizer.


text:
Panerai Watches
-£420
Luminor Composite 1950 3 Days Ltd.
Unworn - New
Luminor Marina Carbotech
Luminor 1950 Marina 3 Days
-£1,300
Submersible Marina Militare Carbotech™
Radiomir Black Seal
Submersible "SIHH 2019"
Luminor 1950 Tuttonero 3 Days GMT Automatic Ceramica
Luminor Automatic
Luminor Marina Power Reserve
Luminor Luminor Marina
Luminor 1950 Submersible Depth Gauge
Luminor Chrono Daylight Ivory
Luminor Base Logo
Luminor Luna Rossa GMT
Radiomir Black Seal Logo
Panerai: History, Models and Prices. New & Vintage.
Panerai Watches – Made in Italy
Discover the world of Panerai watches online.
As an official supplier to the Italian Navy, the watch manufacturer Officine Panerai enjoys a fascinating history. The most famous models from the house are the Radiomir and the Luminor, which, for an extended period of time, belonged among the standard equipment of the Italian frogmen. Since the 1990s, the watches from Panerai have been made available to the market and delight with their striking aesthetics.
Giovanni Panerai founded his watchmaking shop in 1860 Florence, which would later develop into the legendary company Officine Panerai, as we know it today.
In 1938, Officine Panerai designed the famous Radiomir model for divers in the Italian Navy. The timepiece was characterised by high water resistance and optimal legibility.
Officine Panerai watches were established as suppliers for the Italian Navy before the company launched its collection for sale in the year 1993.
Sylvester Stallone assisted the then relatively unknown company Officine Panerai to world fame when he visibly wore a Panerai Luminor in the 1996 movie "Daylight".
Diving watches with Italian roots
The history of Officine Panerai dates back to 1860, when Giovanni Panerai opened a watchmaking shop at Ponte Alle Grazie in Florence. In 1890, his talented grandson Guido Panerai took over the business and relocated it to the Piazza San Giovanni.
Preceding the collaboration of the brand with the Italian Navy, Panerai produced mechanical instruments such as depth gauges and compasses. In 1936, the family received an order of a special kind and began to produce professional diver's watches for the Marines. The Italian Marine Military placed the highest demands on the watch including the need to be waterproof but easily read in any situation. In the development of this pioneering timepiece, Panerai turned to the Swiss company Rolex, which at the time, was already known for its expertise in water resistance.
The cooperation with Rolex resulted in the Panerai Radiomir, which was a waterproof watch with a diameter of 47-millimeters that was considered to be of immense proportions in the 1930s. In order to ensure that the time would be legible in all environments, a patented phosphor based on radium was used in the manufacture of the Radiomir dial. At the time of Radiomir production, nobody was aware that the timepieces were being produced with the most radioactive substance in the world. However, the production of this Radiomir edition was very low since the timepieces were not being sold on the consumer market. Today, the Panerai timepieces constructed for the Italian Navy are some of the most wanted vintage rarities that yield a price range that exceeds the 100,000-euro mark.
From Radiomir to Luminor
Iconic watches from Panerai
Thanks to its unique shape, eye-catching size, and clear dial, the Panerai Radiomir has gained cult status among connoisseurs and collectors. Evidently, the original Radiomir was eventually discontinued due to its radioactive elements. Panerai then developed a new timepiece – the Luminor. As early as 1949, the company filed a patent for the tritium-based compound that they used in their Luminor models. Later on, it was discovered that the compound was also radioactive, but thankfully, it turned out to be harmless in small quantities. Today, the Panerai Superluminova contains a completely safe fluorescent. A word of advice for collectors, however – the Panerai models that contain tritium or even radium increase in price with each passing year.
The greatest difference between the Radiomir and Luminor timepieces – aside from the elements used in production – is the crown protector. The striking crown protector ensures that the crown is pushed against the case of the watch, guaranteeing secure water resistance. This unique element also provides the Luminor with a distinctive character and has come to be one of the hallmarks of Panerai. Another outstanding feature of the timepiece is the case, which measures a spectacular 47-millimeters.
The Panerai Radiomir and the Panerai Luminor are highly recognised timepieces that have gained cult status among connoisseurs in the world of watches. At CHRONEXT you will find a wide range of these coveted models for immmediate delivery offered for best prices. Every watch comes with a two year warranty.
A true rarity
Royalty of the sea: Panerai Mare Nostrum
Nautical elements are an indispensable part of Officine Panerai identity. A great expression of the brand's connection to the seas is the Panerai Mare Nostrum. The watch is a chronograph that was launched in 1943 and was specially developed for deck officers. The spectacular model stood out from the watch crowd thanks to its two counters. The development of the Mare Nostrum fell into the same period in which the characteristic Panerai crown feature was introduced.
It is generally believed that no more than two or three copies of the Panerai Mare Nostrum were created and, until recently, only a few photos of the watch were available. In 2005, one of these exquisite men's timepieces surfaced. As Panerai launched its first collection to the public market in 1993, the Mare Nostrum has been presented as a modern reinterpretation Faithful to the marine spirit.
From the Italian family to a Hollywood favourite
In 1993, Officine Panerai launched its first collection that was not catered towards the Italian Navy, but instead, was created for the general watch loving public. The Panerai collection was inspired by the distinctive designs of the classic Radiomir and Luminor. For some years following, the company remained in the shadows of major manufacturers, whose histories and traditions were widely famous worldwide. But before long, the magic of Panerai could no longer be overlooked.
In the 1996 movie "Daylight", Sylvester Stallone, at his own request, wore the relatively unknown Panerai Luminor (Ref. 5218/201-A) around his wrist. The watch can distinctly be viewed in the movie, and so in large part, it's thanks to Sylvester Stallone that the then relatively unknown brand Officine Panerai gained world fame. Following the silver screen debut of the timepiece, Hollywood could not get enough of the Panerai Luminor. As a kind of thanks, Officine Panerai eventually adorned some of their timepieces with the logo "Daylight" or "Slytech" – a reference to Stallone since his nickname is Sly. In the fourth part of the movie "Rambo", Stallone also adorns a Panerai – namely the model utilised by the Italian Navy. Furthermore, in "The Expendables" Stallone wears the Panerai Luminor Regatta around his wrist while playing the role of Barney Ross.
But there are several films in which timepieces from Panerai make and appearance. Among many others, a Panerai Luminor Marina can be spotted around the wrist of Arnold Schwarzenegger in the movie Eraser. Furthermore, the Panerai Luminor Marina can also be spotted around the wrist of DMX in the movie "Exit Wounds - The Copjäger" and a Panerai Luminor Daylight is featured around the wrist of Jason Statham in the movie "Transporter - The Mission".
Simple & secure
Sell your Panerai watch with CHRONEXT
If you do not want to buy a Panerai watch, but would prefer to sell one, CHRONEXT is the place for you. On our online platform, we offer both the purchase and sale of renowned brands like Panerai. You can find more information about this and our online form on our homepage. Alternatively, you can contact our dedicated sales and service team by phone, email, or via our live chat.
Popular Brands & Models at CHRONEXT
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These Terms and Conditions underpins the contract between Untamed Photography Ltd and The Client. In the act of applying to participate on any Untamed Photography Ltd workshop, tour, expedition, or other travel-related product or service, The Client accepts these conditions as well as the Code of Conduct outlined below. In these conditions 'The Company' shall mean Untamed Photography Ltd and all associates, a United Kingdom-registered company limited by guarantee which operates photography tours, workshops, expeditions, and other travel-related products and services at an international level, with an emphasis on South America. 'The Client' shall mean any person who has paid a fee to The Company to participate in one or more of its advertised products or services.
All clients of The Company must have a valid health and/or travel insurance policy in their name before initiating a workshop, tour, expedition, or other travel-related product or service, and waive all rights and claims against The Company, its management team, and any affiliates.
All Clients who make payments to The Company will receive a valid receipt. The non-refundable deposit is payable up to 14 days after the acceptance letter and invoice have been sent to successful applicant. The remaining balance is payable no later than 1 calendar month or 30 days (whichever is the longest) prior to The Client's start date associated with the workshop, tour, expedition or other travel-related product or service, as stipulated in the acceptance letter and invoice. Failure to pay within the specified periods, gives The Company the right to cancel the place and offer it to another applicant.
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Gross misconduct – Gross misconduct will be misconduct deemed to be so serious that The Company can no longer tolerate the presence of The Client. Examples of gross misconduct may include; physical violence; theft; deliberate damage to Company property; possession or use of illegal drugs. A Client who commits such an act will be evicted from the workshop, tour, expedition and other travel-related product and will forfeit any rights to reimbursement.


text:
Home » organic chemistry
Category Archives: organic chemistry
Development of an Efficient Manufacturing Process for a Key Intermediate in the Synthesis of Edoxaban
Makoto Michida*† , Hideaki Ishikawa†, Takeshi Kaneda†, Shinya Tatekabe‡, and Yoshitaka Nakamura§
†Process Technology Research Laboratories (PTRL), Daiichi Sankyo Co., Ltd., 1-12-1 Shinomiya, Hiratsuka-shi, Kanagawa 254-0014, Japan
‡Plant Management Department, Daiichi Sankyo Chemical Pharma Co., Ltd., 477 Takada, Odawara-shi, Kanagawa 250-0216, Japan
§Global Supply Chain – Technology Function, Daiichi Sankyo, Inc., 211 Mt. Airy Road, Basking Ridge, New Jersey 07920, United States
Org. Process Res. Dev. , Article ASAP
DOI: 10.1021/acs.oprd.8b00413
*E-mail: michida.makoto.wp@daiichisankyo.co.jp.
This article is part of the Japanese Society for Process Chemistry special issue
We report the development of a novel synthetic method to access a key intermediate in the synthesis of edoxaban. The main features of the new synthetic method are an improvement in the approach for the synthesis of a key chiral bromolactone, application of an interesting cyclization reaction utilizing neighboring group participation to construct a differentially protected 1,2-cis-diamine, and implementation of plug-flow reactor technology to enable the reaction of an unstable intermediate on multihundred kilogram scale. The overall yield for the preparation of edoxaban was significantly increased by implementing these changes and led to a more efficient and environmentally friendly manufacturing process.
https://pubs.acs.org/doi/10.1021/acs.oprd.8b00413
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Synthesis of highly functional carbamates through ring-opening of cyclic carbonates with unprotected α-amino acids in water
December 20, 2017 10:36 am / Leave a comment
Synthesis of highly functional carbamates through ring-opening of cyclic carbonates with unprotected [small alpha]-amino acids in water
Green Chem., 2018, Advance Article
DOI: 10.1039/C7GC02862H, Paper
Peter Olsen, Michael Oschmann, Eric V. Johnston, Bjorn Akermark
Ring opening of cyclic carbonates with unprotected amino acids in water – a route to highly functional carbamates.
Peter Olsén,*a Michael Oschmann,a Eric V. Johnston*a and Björn Åkermark*a
*Corresponding authors
aDepartment of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE 106 91, Stockholm, Sweden
E-mail: peter.olsen@su.se, eric@sigridthx.com, bjorn.akermark@su.se
The present work shows that it is possible to ring-open cyclic carbonates with unprotected amino acids in water. Fine tuning of the reaction parameters made it possible to suppress the degree of hydrolysis in relation to aminolysis. This enabled the synthesis of functionally dense carbamates containing alkenes, carboxylic acids, alcohols and thiols after short reaction times at room temperature. When Glycine was used as the nucleophile in the ring-opening with four different five membered cyclic carbonates, containing a plethora of functional groups, the corresponding carbamates could be obtained in excellent yields (>90%) without the need for any further purification. Furthermore, the orthogonality of the transformation was explored through ring-opening of divinylenecarbonate with unprotected amino acids equipped with nucleophilic side chains, such as serine and cysteine. In these cases the reaction selectively produced the desired carbamate, in 70 and 50% yield respectively. The synthetic design provides an inexpensive and scalable protocol towards highly functionalized building blocks that are envisioned to find applications in both the small and macromolecular arena.
link http://pubs.rsc.org/en/Content/ArticleLanding/2018/GC/C7GC02862H?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract
Department of Organic Chemistry
PostDoc Position
Research experience
KTH Royal Institute of Technology · Department of Fibre and Polymer Technology
Sweden · Stockholm
Björn Åkermark
Jan 1962–Jun 1967
Organic Chemistry and Catalysis · PhD
Award: Bror Holmberg Medal, Swedish Chemical Society
Award: Ulla and Stig Holmquists Prize, Uppsala University
Award: Dr hc, University D´Aix-Marseille
Award: KTH Prize for Excellence in Teaching
Award: Arrhenius Medal, Swedish Chemical Society
Scholarship: Zorn Fellowship, Swden America Foundation
Award: Letterstedt Award, Roy Swed. Acad. of Science
Dr. Eric Johnston, Ph.D.
Dr. Eric V. Johnston obtained his Master of Science degree in 2008 at the Department of Organic Chemistry, Stockholm University, Sweden. In the same year, he started his graduate studies under the supervision of Prof. Jan-Erling Bäckvall. During his PhD, he worked on the development of new homogeneous and heterogeneous transition-metal catalysts.
After receiving his PhD in 2012, he joined Prof. Samuel J. Danishefskys research group at Memorial Sloan-Kettering Cancer Center, New York, USA as a postdoctoral fellow supported by The Swedish Research Council. Here he was engaged in the total chemical synthesis of glycolsylated proteins that play important roles in modern cancer treatment.
In 2014 he returned to the Department of Organic Chemistry at Stockholm University to establish his own group. The goal of his research is to contribute new advances to the strategy and methodology for the preparation of synthetic macromolecules such as proteins, glycopeptides, sequence and length-controlled polymers. He is also a Co-Supervisor for Prof. Björn Åkermarks research group, which aims at studying and developing new homogeneous, as well as heterogeneous, water oxidation catalysts.
How flow chemistry can make processes greener…………Supercritical fluids
July 23, 2015 10:49 am / 1 Comment on How flow chemistry can make processes greener…………Supercritical fluids
Safe, small scale access to supercritical fluids
The ability to safely access high temperatures and pressures in flow reactors has implications not only on the rate of chemical reactions, but also on the types of solvents one can use. Many greensolvents such as methanol and acetone have boiling points too low for certain batch applications, whereas performing reactions at high pressure in a flow reactor may allow for their safe use at elevated temperatures.
Supercritical fluids are particularly interesting, since these solvents are entirely inaccessible without high pressure conditions. The use of supercritical fluids in a flow system offers numerous advantages over batch reactors.
Reactions may be performed on a small scale, improving safety and reducing the amount of material required. Depending on the type of reactor, it may be possible to visualize the reaction to evaluate the phase behaviour. Moreover, the reaction can be analyzed and the temperature and pressure subsequently changed without stopping the reaction and cleaning the vessel, as is necessary in a simple autoclave.
Continuous methods for utilizing supercritical fluids for extraction,1 chromatography,2 and as a reaction medium3 have all been commercialized, particularly for supercritical carbon dioxide (scCO2).4 Academic examples using scMeOH, scH2O, and scCO2 for continuous reactions such as hydrogenations, esterifications, oxidations, and Friedel–Crafts reactions have been reported.5
A recent example that illustrates many of the green advantages of performing supercritical fluid chemistry in flow is in the ring opening of phthalic anhydride with methanol by Verboom and co-workers (Scheme 1).6 They designed a microreactor with a volume of just 0.32 μL that can withstand very high pressures.
The exceptionally small channel causes a large build-up of pressure, and supercritical conditions with pressures of up to 110 bar and temperatures up to 100 °C can occur inside the reactor, giving an 'on-chip' phase transition. The channel size increases near the outlet, allowing the fluid to expand to atmospheric conditions.
Thus, the total volume of scCO2 under high pressure is exceptionally small, alleviating the major hazards of operating under supercritical conditions. The reaction was thoroughly studied on this small scale, allowing the authors to determine rate constants at several different temperatures and pressures.
Scheme 1 Small scale continuous use of supercritical fluids.
Near- and supercritical water (scH2O) can be an interesting green solvent only obtainable at very high temperature (Tc = 374 °C) and pressure (Pc = 221 bar). It is commonly used for completeoxidation of organic waste materials to CO2; however, it has also been shown to be an effective solvent for selective oxidations.7 Given the harshness of the reaction conditions, it is not surprising that side product formation is common and highly dependent on the reaction time. For fast reactions in a batch reactor, precise control of reaction time is challenging, as the vessel takes time to heat and cool. In contrast, rapid heating, cooling, and quenching can be accomplished in a continuous process, allowing for well defined reaction times.
Fine tuning of the temperature, pressure, and time is also easier in a continuous process, as these variables can be changed without stopping and starting the reaction between samples. Thus, more data points can be obtained with less material and fewer heating and cooling cycles.
The Poliakoff group used these advantageous to perform a detailed study on the oxidation of p-xylene to terephthalic acid in scH2O, a reaction carried out on industrial scale in acetic acid (Scheme 2).8 By using a flow reactor, reaction times as low as 9 seconds could be used. The equivalents of oxygen could also be finely varied on a small scale through the controlled thermal decomposition of H2O2.
Studying this aerobic oxidation with such precision in a batch process would prove highly challenging. Under optimal conditions, excellent selectivity for the desired product could be obtained. Further research by the same group identified improved conditions for this transformation.9
Scheme 2 Selective oxidation in supercritical water.
Schematic Diagram of sample Supercritical CO2 system
Table 1. Critical properties of various solvents (Reid et al., 1987)
Critical pressure
Critical density
g/mol K MPa (atm) g/cm3
Carbon dioxide (CO2) 44.01 304.1 7.38 (72.8) 0.469
Water (H2O) (acc. IAPWS) 18.015 647.096 22.064 (217.755) 0.322
Methane (CH4) 16.04 190.4 4.60 (45.4) 0.162
Ethane (C2H6) 30.07 305.3 4.87 (48.1) 0.203
Propane (C3H8) 44.09 369.8 4.25 (41.9) 0.217
Ethylene (C2H4) 28.05 282.4 5.04 (49.7) 0.215
Propylene (C3H6) 42.08 364.9 4.60 (45.4) 0.232
Methanol (CH3OH) 32.04 512.6 8.09 (79.8) 0.272
Ethanol (C2H5OH) 46.07 513.9 6.14 (60.6) 0.276
Acetone (C3H6O) 58.08 508.1 4.70 (46.4) 0.278
Nitrous oxide (N2O) 44.013 306.57 7.35 (72.5) 0.452
Table 2 shows density, diffusivity and viscosity for typical liquids, gases and supercritical fluids.
Comparison of Gases, Supercritical Fluids and Liquids
Density (kg/m3)
Viscosity (µPa∙s)
Diffusivity (mm²/s)
Supercritical Fluids
100–1000 50–100 0.01–0.1
1000 500–1000 0.001
F. Sahena, I. S. M. Zaidul, S. Jinap, A. A. Karim, K. A. Abbas, N. A. N. Norulaini and A. K. M. Omar, J. Food Eng., 2009, 95, 240–253
D. J. Dixon and K. P. Jhonston, in Encyclopedia of Separation Technology, ed. D. M. Ruthven, John Wiley, 1997, 1544–1569
P. Licence, J. Ke, M. Sokolova, S. K. Ross and M. Poliakoff, Green Chem., 2003, 5, 99–104
X. Han and M. Poliakoff, Chem. Soc. Rev., 2012, 41, 1428–1436
S. Marre, Y. Roig and C. Aymonier, J. Supercrit. Fluids, 2012, 66, 251–264
F. Benito-Lopez, R. M. Tiggelaar, K. Salbut, J. Huskens, R. J. M. Egberink, D. N. Reinhoudt, H. J. G. E. Gardeniers and W. Verboom, Lab Chip, 2007, 7, 1345–1351
R. Holliday, B. Y. M. Jong and J. W. Kolis, J. Supercrit. Fluids, 1998, 12, 255–260
P. A. Hamley, T. Ilkenhans, J. M. Webster, E. García-Verdugo, E. Vernardou, M. J. Clarke, R. Auerbach, W. B. Thomas, K. Whiston and M. Poliakoff, Green Chem., 2002, 4, 235–238
E. Pérez, J. Fraga-Dubreuil, E. García-Verdugo, P. A. Hamley, M. L. Thomas, C. Yan, W. B. Thomas, D. Housley, W. Partenheimer and M. Poliakoff, Green Chem., 2011, 13, 2397–2407
ANTHONY MELVIN CRASTO
सुकून उतना ही देना प्रभू, जितने से जिंदगी चल जाये। औकात बस इतनी देना, कि औरों का भला हो जाये।
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जिंदगी चल जाये।
औकात बस इतनी देना,
कि औरों का भला हो जाये।
Total synthesis of the proposed structure of Astakolactin……….Dr Corey Johnson
December 6, 2014 12:40 pm / 1 Comment on Total synthesis of the proposed structure of Astakolactin……….Dr Corey Johnson
picture credit…………Dr Corey johnson
Astakolactin is a sesterpene from the Ionian Sea near Greece possessing considerable biological properties. Hence, that's why the authors decided to synthesize it, and also why the we're all interested in its structure. In the conclusion of this paper, no biological studies were performed, but the characterization matches that of the natural product, which is a big deal.
http://chemistrycorey.blogspot.in/2014/11/total-synthesis-of-proposed-structure.html
A lovely blog and its great author
Corey R. Johnson
Philly native, JCSU alumnus, Brandeis alumnus, Co-author of several scholarly journal articles…
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Optimisation of Conditions for O-Benzyl and N-Benzyloxycarbonyl Protecting Group Removal using an Automated Flow Hydrogenator
October 28, 2014 7:00 am / Leave a comment
K.R. Knudsen, J. Holden, S.V. Ley and M. Ladlow, Adv. Syn. Cat. 2007, 349, 535-538.
http://onlinelibrary.wiley.com/doi/10.1002/adsc.200600558/abstract
A versatile, fully automated flow hydrogenator has been developed that is able to perform sequential flow optimisation experiments, flow library hydrogenation, or iterative scale-up hydrogenation. The behaviour of a palladium catalyst in effecting removal of O-benzyl and N-benzyloxycarbonyl protecting groups has been investigated. Significant observations relating to maintaining optimal throughput are reported. A small library of peptidic derivatives has been deprotected in high yield and purity.
The system used was configured from a Gilson liquid handler (233XL), driven with a 10 mL
syringe pump (402). The syringe pump was connected to the sampling needle via a 2-way 6
position switching valve. This single channel liquid handler was used to perform both substrate
manipulation and fraction collection. The liquid handler was connected via a 2-way 6 position
injection valve to a Thales H-CubeTM flow hydrogenator driven with a KnauerTM A120 high
pressure pump. The collection vials were housed in specially designed gas tight blocks (2 x 7)
which were fitted with PTFA seals to enable penetration by the liquid handler needle, and
continuously purged with nitrogen in order to dilute and vent excess hydrogen safely. The
hardware was controlled using a single graphic user interface (HydroMateTM, Figure 2) which
utilised either RS232 or GSIOC connectivity to interface with the Thales and Gilson devices
respectively. Throughout 30 mm, 4 mm id 10% Pd/C catalyst cartridges (CatCartTM) were used
in conjunction with a 5 mL sample injection loop, although larger cartridges are also available.
The control software exploits software 'wizards' to assist the user in compiling a sequence of
optimisation experiments, or alternatively permits the implementation of a series of repetitive
experiments for either: (i) catalyst evaluation, (ii) reaction optimisation, (iii) compound library
synthesis, or (iv) as part of an automated, unattended scale up campaign (Figure 1). Experiments
may be devised with variations in scale, temperature, flow rate, and pressure in addition to
periodicity of fraction collection.
Analysis: RP-HPLC was run on a Hewlett Packard 1050 instrument. Column: Supelcosilä
ABZ+
PLUS column, 3.3 cm, 4.6 mm f, 3 mm. Eluent: A: water, 0.1% TFA, B: acetonitrile 95%,
water 5%, TFA 0.05%. Gradient: 10 to 95% B in A (1 mL min-1
) over 8 min. Detection: UV
(diode array detector).
A Microcapillary Flow Disc (MFD) Reactor for Organic Synthesis
October 28, 2014 6:50 am / 1 Comment on A Microcapillary Flow Disc (MFD) Reactor for Organic Synthesis
A Microcapillary Flow Disc (MFD) Reactor for Organic Synthesis,
C.H. Hornung, M.R. Mackley, I.R. Baxendale and S.V. Ley and, Org. Proc. Res. Dev., 2007, 11, 399-405.
http://pubs.acs.org/doi/abs/10.1021/op700015f
This paper reports proof of concept, development, and trials for a novel plastic microcapillary flow disc (MFD) reactor. The MFD was constructed from a flexible, plastic microcapillary film (MCF), comprising parallel capillary channels with diameters in the range of 80−250 μm. MCFs were wound into spirals and heat treated to form solid discs, which were then capable of carrying out continuous flow reactions at elevated temperatures and pressures and with a controlled residence time. Three reaction schemes were conducted in the system, namely the synthesis of oxazoles, the formation of an allyl-ether, and a Diels−Alder reaction. Reaction scales of up to four kilograms per day could be achieved. The potential benefits of the MFD technology are compared against those of other reactor geometries including both conventional lab-scale and other microscale devices.
Continuous Flow Ligand-Free Heck Reactions Using Monolithic Pd[0] Nanoclusters
N. Nikbin, M. Ladlow, S.V. Ley, Org. Proc. Res. Dev., 2007, 11, 458-462.
Flow-through reactor setup.
An automated reactor has been developed for performing ligand-free Heck reactions in continuous flow mode. The reactor utilises a monolithic reactor cartridge derivatised with Pd(0) nanoparticles in-line with a scavenging cartridge containing Quadrapure-TU to efficiently capture palladium residues and thereby afford Heck products directly in high purity.
Piecing together the puzzle: understanding a mild, metal free reduction method for large scale synthesis of hydrazines
October 25, 2014 11:36 am / Leave a comment
D.L. Browne,* I.R. Baxendale, S.V. Ley, Tetrahedron2011, 67, 10296-10303.
A key intermediate for the synthesis of hydrazines via a mild, metal free reduction of diazonium salts has been isolated and characterized by X-ray analysis. The presence of this intermediate is general, as demonstrated by the preparation of a number of analogues. A discussion of the mechanism and potential benefits of such a process are also described.
FLOW SYNTHESIS IN ACTION
October 25, 2014 11:24 am / 2 Comments on FLOW SYNTHESIS IN ACTION
Multi-step synthesis using modular flow reactors: the preparation of yne-ones and their use in heterocycle synthesis
I.R. Baxendale, S.C. Schou, J. Sedelmeier, S.V. Ley, Chem. Eur. J. 2010, 16, 89-94.
http://onlinelibrary.wiley.com/doi/10.1002/chem.200902906/abstract
http://onlinelibrary.wiley.com/store/10.1002/chem.200902906/asset/supinfo/chem_200902906_sm_miscellaneous_information.pdf?v=1&s=e659fdc2121b72d28f3caeea481a89cc3278bc01
Multi-step in flow: The palladium-catalysed acylation of terminal alkynes for the synthesis of yne ones as well as their further transformation to various heterocycles in a continuous-flow mode is presented. Furthermore, an extension of the simple flow configuration that allows for easy batch splitting and the generation of a heterocyclic library is described (see scheme).
Advanced Intermediate Flow Studies: Nevirapine
SynthFlow
After looking through a number of flow articles that describe and illustrate processes toward the production of drug final products and advanced intermediates, I thought an article from Florida State — Tyler McQuade (open source Beilstein JOC 2013) was informative and storytelling. He was able to show some of the challenges that go into designing a flow methodology around process that have already been worked out in batch mode, and had been looked at in a number of labs already.
Before talking about the chemistry, Professor McQuade talks about a number of concerns in transferring technology from batch to flow: DOE, solvent exchange (precipitation and moving from one reaction to another), Cost of Goods Analysis – reaction concentrations, solvent costs, process time, by-product formation and purification. There certainly is a lot that goes into the strategy. To give you the framework: this group was looking to make a continuous process…