Right now, if you want to test water in the field, you need a trained technician, expensive equipment like this, and you have to wait about a day for chemical reactions to take place and provide results.
目前，如果你想检测一个地区的水质 需要一名接受过专业训练的人员 像这样昂贵的设备 然后再等将近一天的时间 等那些化学反应结束之后才能得到最后的结果