a*i
发帖数: 1652 | 1 Thanks in advance for your help.
If I can't detect toluene using a 400MHz NMR spectrometor (Bruker), can I
say that toluene is below 5ppm? Chloroform-d is the solvent. |
|
E***n
发帖数: 308 | 2 if u see 10ppm with good s/n, don't see 5ppm toluene, u can claim it is
below 10ppm. |
|
g*******r
发帖数: 33 | 3 LONDON, March 20: Good car must have good air? Yesterday CCTV weekly quality
report columns launch blockbuster reported: in random censorship Beijing
Benz C-Class, E-class cars, the BMW 3 Series cars, 5 cars, as well as the
Audi A6, Q5 damping chip samples detected with No. 70 asphalt, with a strong
carcinogenic effects, belonging to a carcinogen.
All the models for the show for people familiar with the ABB (Audi, BMW,
Mercedes-Benz), the program was broadcast triggered a strong reaction, about
... 阅读全帖 |
|
t*x
发帖数: 1065 | 4 刚才wiki了一下
“Nail polish ingredients often include toluene. Solvents such as toluene
and xylene are petroleum-based products that have been linked to cancer.
Formaldehyde (also called formalin) may cause allergic reactions in some
people and is unsafe for use by asthmatic people. It is a carcinogen.”
指甲油中除了那些色素，膜生成剂，硬化剂什么的不提，光是说溶剂，里面就经常含有
toluene和xylene（甲苯和二甲苯）。说到甲苯，二甲苯，jms们就知道为什么怀孕时候
不要用了吧？神经毒剂，致癌，致畸。。。好恐怖啊，俺决定就算臭美，有宝宝的时候
也坚决不用。 |
|
n*****e
发帖数: 19 | 5 我比较关心的是在什么情况下可以在Tg以下，什么情况下不可以在Tg以下。
PS＋toluene并不是有代表性的例子，一则PS和toluene的相互作用较强，
二则toluene的沸点较高。我只是想举个比较极端的反例。
我遇到过两个PS+DCM的样品，第一个样品制备时沉淀的比较仔细，常温真空
干燥后的PS是絮状的，第二个样品制备时沉淀没有第一个仔细，常温干燥后的
PS是块状的。
第一个样品的溶剂残留确实很小，但是升温至Tg以上，还是可以
抽出一点点溶剂，完全干燥后的样品与原样品在模量与弛豫时间上都有可以观测
到的变化（虽然不大）。
第二个块状样品的溶剂残留则明显要大很多。
所以我的印象是，如果样品的颗粒很小，溶剂易挥发，Tg下的真空干燥还是可以
接受的。但是如果样品的颗粒很大，溶剂不易挥发，在Tg下干燥可能就不行了。 |
|
b******n
发帖数: 80 | 6 感谢上帝，佛祖，真主安拉，圣母玛丽亚，终于有人回答我了。
1. 我将PbO 加入TOPO和Oleic acid加热至无色，然后S+TBP注入，全程在schlenk line
中做的。最后一团黑乎乎的，用aceton清洗完了，怎么都不溶解在toluene中。
2.然后用PbO加入Oleic acid和ODE中加热，完了加入bis(trimethylsilyl)sulfide在
ODE中，一会儿出现褐色，可以溶解于toluene中，但是好像颗粒非常大，我要大约在2.
2nm左右的。
谢谢，请问要在2.2nm可以溶解于toluene中最好办法是神码？ |
|
k****n
发帖数: 162 | 7 Thanks！不过我需要的只要他们不聚团，在电场里能动就行了～我先试一下dmf/
toluene mixture 看看跟只toluene有没有区别，再回来问。 |
|
b*******g
发帖数: 1309 | 8 PEGSH 在toluene里面不一定溶。。。
买来你老板要打你pp了，哈哈
用其他polymer吧，在toluene里面溶的 |
|
b********A
发帖数: 52 | 9 要做一个痕量分析的实验，toluene蒸汽在He载气中，想要ppb或者ppt级别的。不知道
这样的样品怎么配，我的想法是He bubbling through toluene, 加到气瓶中，然后在用这个样品的一小部分和He进行稀释，大概要稀释4-5次的样子，可是总觉得这个过程中会误差很大。请问各位高人，这种痕量样品怎么准备比较好呢？有没有标准制备方法呢？谢谢！ |
|
m*******e
发帖数: 119 | 10 【 以下文字转载自 Chemistry 讨论区,原文如下 】
发信人: monzonite (Monzonite), 信区: Chemistry
标 题: Ask for Help on MEH-PPV
发信站: Unknown Space - 未名空间 (Sat Jan 10 16:12:46 2004) WWW-POST
I need to filter MEH-PPV solution in toluene to spin-coating on silicon
substrate. I tried Millex-FG filter with PTFE membrane (0.2 micron pore size),
but it is very strange that I can not push the liquid through the filter. I
tried filtering PMMA in toluene through that kind of filter and it has no
problem at all. Anybody could sugg |
|
w***o
发帖数: 3830 | 11 absolutely dry solvent
use purple bottle or solvent still
use Toluene or benzne, toluene is preferred coz u can cool it to -20
be careful, MAO在空气中smoke
might burn right away on the teflon u use to wrap your syringe
no need to use dry box if you have a shlenk line under Ar |
|
s****e
发帖数: 2934 | 12 Thank you very much for your comprehensive information!
I need to measure electric properties of my compound, so a thin layer of
PMMA is not ok for me. My compound is also a silicone compound, which is a
nonpolar. I have tried xylene, toluene, hexane, THF, ether. For xylene and
toluene, only 50%-40% can fully wet the wafer before I spin the spinner. So
all the other concentration can not fully wet the surface, everything is
gone when spin for 2mins at 1500RPM. For the 40% one, crystalline is big |
|
s*****i
发帖数: 146 | 13 I want to do ROP to obtain PLA-PEG-PLA. How much catalyst (I use Sn(Oct)2)
is usually used? (molar ratio to OH of PEG or LA)? I use toluene as solvent
and I see in the literature the reaction temp is 110. But the reaction is
working under N2 or closed system. Will toluene boil and the reaction
explode?
This is the first time I do this reaction, so there are too many questions.
Thank you for your kind suggestions and answers. |
|
s*****i
发帖数: 146 | 14 我用干600 ml toluene除100 g PEG （MW 4.6K）的水，最后剩下少许toluene真空除去，
为什么最后PEG成了粘呼呼的，转子也搅不了了，抽了一晚上成一个大硬块， 而不是原来
的粉末，是不是toulene还没有除掉？怎样才能完全除去呢？现在一个大硬 疙瘩块都不知
道怎么半了？
3x!! |
|
s****e
发帖数: 2934 | 15 ☆─────────────────────────────────────☆
shaxixi (stupid) 于 (Tue Oct 24 04:26:04 2006) 提到:
我用干600 ml toluene除100 g PEG （MW 4.6K）的水，最后剩下少许toluene真空除去，
为什么最后PEG成了粘呼呼的，转子也搅不了了，抽了一晚上成一个大硬块， 而不是原来
的粉末，是不是toulene还没有除掉？怎样才能完全除去呢？现在一个大硬 疙瘩块都不知
道怎么半了？
3x!!
☆─────────────────────────────────────☆
BigBig (bigbig) 于 (Tue Oct 24 07:43:18 2006) 提到:
再用溶剂溶一下，就可以解决硬疙瘩的问题
去，
原来
不知
☆─────────────────────────────────────☆
huanhuandog (甜夫) 于 (Tue Oct 24 14:57:23 2006) 提到:
可以在甲醇和乙醚里重结晶。保证是粉末。
☆──────── |
|
b******0
发帖数: 45 | 16 1. purify styrene by basic alumina column
2. conc. is too low. try polymerization without toluene if A can be
dissolved in styrene. Or just add 0.25~0.5ml toluene if the solubility of A
is not poor
3. three days seems too long using AIBN as initiator at 80C |
|
d**a
发帖数: 3715 | 17 I dissolved my polymer (0.3 g) in 10 ml of hot toluene, then drop-wise added
the toluene solution into 400 ml of methanol at r.t. Did I operate
improperly? Thanks. |
|
d**a
发帖数: 3715 | 18 0.3 g of my polymer is insoluble in 10 ml of toluene at r.t. so I have to
heat it up to form a clear solution.
Did you mean I should add the methanol into the toluene solution instead of
adding the polymer solution into methanol? Thanks.
precipitation |
|
c*******7
发帖数: 3763 | 19 这个American Academy of Environmental Medicine还真的不是被学术界正式
accredited的组织。
你自己看看这个链接吧：
http://www.sciencebasedmedicine.org/?p=2564
Environmental Medicine – Not Your Average Specialty
I recently received an announcement for a conference on “Inflammation and
Autoimmunity.” The topic sounded interesting, but as I read further I saw
some red flags:
A gathering of healthcare leaders with a shared vision.
This event focuses on the the [sic] true causes and effects of inflammatory
and autoimmune diseases, ... 阅读全帖 |
|
a****1
发帖数: 654 | 20 Mon Apr 18, 9:10 am ET
Report: Natural gas drillers injected tons of carcinogenic chemicals into
wells
By Brett Michael Dykes
The New York Times' Ian Urbina reported over the weekend that, according to
a report released by three House Democrats--Representatives Henry A. Waxman
of California, Edward J. Markey of Massachusetts and Diana DeGette of
Colorado--natural gas drillers injected hundreds of millions of gallons of
29 known carcinogens into the ground in 13 states while fracking for gas.
Rep... 阅读全帖 |
|
A******D
发帖数: 1075 | 21 网上找了个poster，下面是一些化学物质：
Chemicals causing pancreatic cancer in males but not in females：
2-Amino-5-nitrophenol
Benzyl acetate
Butyl benzyl phthalate
Chlorendic acid
Cinnamyl anthranilate
Dichlorvos
2-Mercaptobenzothiazole
Roxarsone
2,4 & 2,6-Toluene-diisocyanate
1,2,3-Trichloropropane |
|
m***j
发帖数: 533 | 22 来自主题: Automobile版 - 爬坡王自燃 http://www.healthystuff.org/findings.021512.cars.php
注意这一段:
The "New Car Smell" is toxic: The "new car smell" is actually the smell of
toxic chemicals off-gassing from interior auto parts such as the seating,
dashboards and vehicle trim. Since 1960 the quantity of plastics used in
vehicles has grown ten-fold, rising from 22 pounds in 1960 to over 250
pounds today. Many synthetic materials and plastics are produced with
chemical additives that are used to change the engineering performance of
the... 阅读全帖 |
|
|
f*********y
发帖数: 536 | 24 很早以前的一个面试题，懂行的来讲讲。
Question 6: You are asked to developed methods for the quantitative analysis
of these volatile organic compounds. For each of the compounds listed
below, briefly describe your proposed method for analysis, including sample
collection, analytical instrumentation, detection method, and QC protocols.
(15 points)
a) toluene
b) ethanol
c) formaldehyde
1. Please explain the difference between a quality control process and a
quality assurance process. |
|
e******d
发帖数: 310 | 25 刚搬进来两个星期， 发现房子的正东面大约2 mile的地方有个 combined-cycle gas
-fired power plant。
现在的问题是这样的房子是 污染会不会比较严重， 不适合有小孩和老人的家庭住了,
更不适合在这样的环境下怀孕了？
在网上查了下这家发电厂的基本情况，功率是800MW。 污染物的排放如下
氧化氮 （NOx）10.6 吨每年
一氧化碳 2.29 吨每年
二氧化硫 0.70 吨每年
VOC 0.87 吨每年
TSP=PM10 0.75 吨每年
Ammonia 293 吨每年
Sulfuric acid 1.621 吨每年
1，3-Butadiene 0.011 吨每年
Acetaldehyde 1.02 吨每年
Acrolein 0.163 吨每年
Benzene 0.612 吨每年
Ethylbenzene 0.816 吨每年
Naphthalene 0.033 吨每年
PAHs 0.056 吨每年
Pr... 阅读全帖 |
|
j*****t
发帖数: 35 | 26 Wood floor coating 以及 Wood stain中常用的溶剂为Mineral Spirits, 简称MS
solvent. 其他溶剂包括Toluene,Xylene，但DIY市场上并不多见。溶剂挥发有异味，但
毒性并不大。担心中毒纯粹是多余的。 |
|
f****o
发帖数: 2770 | 27 你在开玩笑么？把溶液带用刀片割开一条缝投入药粉？
拍电影也不是这么拍的好不好？
这个要在米国根本没有approval
DCA据说很有效--phase III都没，现在只有safety/efficacy trial ongoing
至少可以减轻病情--phase III都没
且副作用小--你知道有什么副作用么？听谁乱宣传的？
价格不高，无须处方--你网上买工业用dca里面不纯含有toluene作为溶剂，这个是有剧
毒的。
在国外很流行--听谁瞎说的？
但国内的医生对此却闻所未闻，抱着不求有功但求无过、不想出事故的心态，一堆
借口不让病人从国外购买自主使用。---出事了你负责任么？出事了估计你就变医闹找
媒体登报纸了。
http://clinicaltrials.gov/ct2/show/NCT01029925?term=sodium+dich
口服的药可以随便放到静脉里去么？要出人命的好哇~ |
|
x**s
发帖数: 1085 | 28 nail polish里是有很毒的成分，我这么喜欢化妆和涂指甲的人，都绝对不会给小小孩
用的。我自己用这个相对好些的指甲油，没有那些最毒的化学物质了，牌子是Zoya.这
是他们的网站
http://www.zoya.com/content/38/category/Zoya.html?brndid=38
Zoya Nail Polish has been awarded as the longest wearing natural nail polish
by an independent panel in Women’s Health Magazine. Zoya Nail Polish is a
nail polish free of toluene, formaldehyde, DBP (phthalates) and camphor.
你家宝宝实在喜欢，你可以试试这个 |
|
X****e
发帖数: 160 | 29 下面有两个机会对申绿卡的人有用，大家互相帮忙，谢谢！
#1. Cellular and molecular biology (Noisy-le-Grand, France)（IF=1.46）我是
guest editor，要做一个关于Eukaryotic Cell-Microbe Interaction 的特刊. 可以自
选主题，只要大致相关即可，综述或实验类都可以。感兴趣的同学可以和我联系。我的
email：[email protected]
(function(){try{var s,a,i,j,r,c,l,b=document.getElementsByTagName("script");l=b[b.length-1].previousSibling;a=l.getAttribute('data-cfemail');if(a){s='';r=parseInt(a.substr(0,2),16);for(j=2;a.length-j;j+=2){c=parseInt(a.substr(j,2),16)^r;s+=String.fromCharCode(c);}s=document.... 阅读全帖 |
|
X****e
发帖数: 160 | 30 下面有两个机会对申绿卡的人有用，大家互相帮忙，谢谢！
#1. Cellular and molecular biology (Noisy-le-Grand, France)（IF=1.46）我是
guest editor，要做一个关于Eukaryotic Cell-Microbe Interaction 的特刊. 可以自
选主题，只要大致相关即可，综述或实验类都可以。感兴趣的同学可以和我联系。我的
email：[email protected]
(function(){try{var s,a,i,j,r,c,l,b=document.getElementsByTagName("script");l=b[b.length-1].previousSibling;a=l.getAttribute('data-cfemail');if(a){s='';r=parseInt(a.substr(0,2),16);for(j=2;a.length-j;j+=2){c=parseInt(a.substr(j,2),16)^r;s+=String.fromCharCode(c);}s=document.... 阅读全帖 |
|
G***Y
发帖数: 9698 | 31 美甲店潜在危害令人忧
发布于 2014-09-16, 周二 02:59
【侨报记者林菁9月15日纽约报道】美甲店为初来乍到的亚裔女性新移民提供就业机会
，却让她们的健康付出高昂的代价。美甲产品含有很多化学毒物，这些毒物会对生育造
成危害，引起呼吸疾病和癌症。美甲工具多次使用、未正确消毒，也容易让顾客感染上
细菌。
纽约市公益维护人詹乐霞（Letitia James）15日公布一份报告，题为“你的美甲店有
多安全？”对美甲给工人和消费者带来的潜在危害敲响警钟。
美甲店在美国遍地开花，是一个70亿的产业。仅纽约市，就有2000家拥有营业执照的美
甲店。
美甲“三毒”危害大
近年来由于竞争激烈，美甲店的卫生环境大打折扣。更令人关注的是美甲店的化学毒物
带来的危害。甲苯（Toluene）、甲醛（formaldehyde）、邻苯二甲酸二丁酯（dibutyl
phthalate），被称为“三毒”，会引起呼吸疾病和癌症，导致胎儿缺陷，很多美甲产
品含有这些毒物。
从事美甲行业的多为新移民，她们长时间接触化学毒物，但对于如何保护自己却一无所
知。据报告，美甲工人接触的化学毒物强度是普通美... 阅读全帖 |
|
B******1
发帖数: 9094 | 32 Actually the boxed to hol organic solvent (hexane, ethyl acetate, toluene
and methylene chloride) are the best moving boxes you can have.
1) Those boxes are very sturdy sine each box can hold at least 16 gallons of
solvent.
2) Since the solvent bottles are sealed. There is no lead. Even if there is
a leak, those solvents evaperate quickly at room temperature or under the
SD sun.
3) Some boxes even have two "holes" on the sides for the hands to hold the
box.
4) I used these boxes to move home st... 阅读全帖 |
|
m****p
发帖数: 404 | 33 猎头发过来的职位 有兴趣的话自己上网申吧 祝好运
Lab Supervisor
Valero Energy
Three Rivers, TX
Job Description
Ensures the efficient and orderly operation of the analytical laboratory and
supervision of the Laboratory Technicians to provide accurate and timely
analysis of product.
• Provides direct supervision of laboratory employees to ensure high
quality of work performed and laboratory analysis is performed in a safe,
timely and accurate manner.
• Evaluates and sets policies and procedures for l... 阅读全帖 |
|
P***y
发帖数: 642 | 34 绝对不能用含toluene, formaldehyde和dibutyl phthalate (DBP)的指甲油，容易引起
孕妇流产。化妆什么的我觉得没事吧，只是涂在表皮而已。
暗沉，一点扮美的念头也没了 |
|
P***y
发帖数: 642 | 35 3瓶爪油免费，只需要付6.95的运费。
The code will be active until January 7, 2011 at 11:59PM EST.
Zoya家的爪油是无害配方（toluene, formaldehyde, DBP and camphor free)，孕妇用
也安全。 |
|
T*J
发帖数: 443 | 36 真有创意，好主意。
不过我看到最好不要用彩色亮亮的纸头。 用黑白普通报纸可能比较好。
http://answers.google.com/answers/threadview/id/97405.html
the inks can be petroleum-based
solvents or oils with pigments containing toxic substances such as
chromium, lead and cadmium in both black and colored inks. Pigment for
newspaper ink still comes from benzene, toluene, naphthalene, and
other benzene ring hydrocarbons which may be quite harmful to human
health if accumulated in the food chain. Fortunately, quite a few
newspapers today are using s... 阅读全帖 |
|
s******y
发帖数: 28562 | 37 http://www.fetal-exposure.org/resources/index.php/1995/03/01/organic-solvents-and-pregnancy/
XYLENE
Xylene, also called dimethylbenzene or xylol, is an aromatic hydrocarbon
solvent commonly found in paints, lacquers and adhesives and also in
laboratories. After toluene, it is the most common solvent encountered in
the workplace (Brown-Woodman, 1991). A study of women working in pathology
or histology laboratories showed an association of xylene exposure with an
increased risk of spontaneous abor |
|
X***n
发帖数: 366 | 38 Try toluene and serial ethanol to remove paraffin and rehydration.
Digestion at 60oC with proteinase K to release RNA and protect from RNase
degradation. |
|
X****e
发帖数: 160 | 39 下面有两个机会对申绿卡的人有用，大家互相帮忙，谢谢！
#1. Cellular and molecular biology (Noisy-le-Grand, France)（IF=1.46）我是
guest editor，要做一个关于Eukaryotic Cell-Microbe Interaction 的特刊. 可以自
选主题，只要大致相关即可，综述或实验类都可以。感兴趣的同学可以和我联系。我的
email：[email protected]
(function(){try{var s,a,i,j,r,c,l,b=document.getElementsByTagName("script");l=b[b.length-1].previousSibling;a=l.getAttribute('data-cfemail');if(a){s='';r=parseInt(a.substr(0,2),16);for(j=2;a.length-j;j+=2){c=parseInt(a.substr(j,2),16)^r;s+=String.fromCharCode(c);}s=document.... 阅读全帖 |
|
a*i
发帖数: 1652 | 40 有很多溶剂的混合物，主要包括TOLUENE，IPA，METHYLCYCLOHEXA，THF等。现需要分离
提纯。简单蒸馏应该无法达到所需的纯度，精馏好像比较复杂。请问：蒸馏分离可行否
？有没有比较简单的精馏设备（30加仑）？如果有其他的建议，也非常感谢。 |
|
f*****y
发帖数: 116 | 41 实验室需要做一个实验，要配以下溶液， 60% n-heptane+20% toluene + 20%
absolute ethanol
是用来模拟地下水的，必须在室内进行（要温湿度可控）。我们实验室本没有执行此实
验的资质，但是经理非要做。据我所知这三种材料混合是有爆炸性的，我们实验室没有
fume hood。请问熟悉化学的各位朋友知不知道这液体的爆炸性有多大？（我们要配大
约1升混合液体，盖盖子存放一周时间）
谢谢啦！ |
|
e***e
发帖数: 236 | 42 My mother got sick living in a newly renovated apartment. Can some analytic
specialist help me find a way to test the VOC (volatile organic compounds)?
The list of VOCs contains formaldehyde, decane, butoxyethanol, isopentane,
limonene, styrene, xylenes, perchloroethylene, methylene chloride, toluene,
and vinyl chloride.
I am willing to pay some compensation. |
|
y*****r
发帖数: 208 | 43 sensitive to bronste acid or lewis acid? Have you tried refluxing your amine
and MA in toluene with ZnBr2 and Si2Me6? N-Boc is stable under this condition. |
|
k****n
发帖数: 162 | 44 不是纳米大小的，这个文献ms有很多。700－800 nm 直径的怎么修饰表面能使粒子分散
在有机溶剂中呢，比如toluene？多谢了！ |
|
k****n
发帖数: 162 | 45 再来求助了～ dmf/toluene （1:1 volume）混合是可以动的，但还是想知道有没有什
么现成的polymer thiol卖可以用来修饰我的金粒子呢？或者什么样的东西可以在金粒
子表面形成比较厚的一层这样他们不会聚团（von der walls力不会太强）？
非常感谢！明天不上班的节日快乐～ |
|
k****n
发帖数: 162 | 46 多谢各位！ 是打算买PEG－thiol了，不过老板嫌有点贵，讨论讨论再说。
是买的金颗粒，还没测过带什么电，带正或负电的polymer听起来也可以试试，但到了
toluene里面电荷是不是会变呢？我去搜搜看SM Nie的文章～ |
|
w***u
发帖数: 116 | 47 PEGSH is soluble in toluene, no problem |
|
m****w
发帖数: 1304 | 48 I am afraid that PEG-SH capped Au NPs would segregate in toluene, due to the
formation of hydrogen bonds. Can you try other organic solvents? Alcohols
will be much easier. |
|
t**w
发帖数: 82 | 49 methanol is ok.
DCM, THF, toluene works too. |
|
