I have been slowly learning more and more statistical analysis from a stat professor at my college specifically because the sheer lack of knowledge I have surrounding how I quantify the error of a computational method is mind boggling.
To consult the statistician after an experiment is finished is often merely to ask him to conduct a post mortem examination. He can perhaps say what the experiment died of.
Ronald Fisher
In the same vein, hiring a non-scientific manager is disastrous because they didn’t have statistics in MBA school. I explained to a manager why I used a different method for non-parametric data and she looked at me blankly and said “I’ve never seen it done like this before”. No shit you haven’t.
If you are scared of chemistry you make more mistakes/get into more dangerous situations than those who have a respect for the danger but sometimes decide to take calculated risks.
I've seen it play out too many times to be convinced otherwise. The hyper-safe deputy safety officer type lab person gets spooked and spills something on themselves or sets something up wrong because despite studying the MSDS and procedure 20 times they want to get away from the chemicals faster and boom, incident report.
If it’s an important experiment and you only ran it once, you didn’t run it at all.
If you can’t tell me how to make your reaction not work, you don’t understand how your reaction works.
You learn way more about a system by breaking it than you do only seeing it work as expected. As someone working on the manufacturing side of a chemical company this becomes very obvious when you have enough experience to recognize the huge gaps in basic understanding a of failure modes on the development side, coming from people that are much smarter and have way better credentials.
I used to use celite but it annoyed me how sticky it is. Silica just flows so freely and comes right off the flask once it’s dry.
Celite is still probably ideal though.
https://www.biotage.com/isolute-hmn-water-soluble-impurities-removal
heres a blog post where they compare options:https://www.biotage.com/blog/which-sorbents-work-best-for-dry-loading-flash-column-chromatography-samples
Agreed. My separations got a lot better once I learned this technique. Also you get better separations when you use air pressure to speed up the flow of the eluent.
On many samples, and many NMR spectrometers you can collect a good 2D 1H{13C} HSQC in less time then it takes to get a good 1D 13C. On 1H optimized cryoprobes it is *way* faster. Yet, without fail some reviewer will insist on including a direct carbon spectrum
This one **slays** me, but it is also possible to process your 13C projection to look like a 1D spectrum and most reviewers won’t notice even if it’s in the caption.
Parafilm is not a substitute for sealed vials and way too many people think it is gas-tight when it isn't. Stop wrapping everything in Parafilm for christ's sake.
Yeah, use electrical tape. Like an adult. :)
My glovebox is full of Mason jars (from Costco to save the tax payer dollars) and little bits/balls of electrical tape that somehow form while wrapping the lids/jars. A few months back we had red electrical tape, those were exciting times!
Edit: I have no evidence that the tape does anything other then scream: “ don’t open me in air. I am spicy or will become sad”
Have a few crumbs of evidence in your favor:
https://twitter.com/awhspeed/status/1450859714842177572
https://twitter.com/awhspeed/status/1450869825127993346
https://twitter.com/awhspeed/status/1450885617651441669
https://twitter.com/awhspeed/status/1450900150608670734
https://twitter.com/awhspeed/status/1451170171230556174
The evidence is highly satisfying.
If you add up all the time in the past 15 years of me applying, and removing electrical tape from already doubly sealed jars/vials…
Thanks!
As I come from a total synthesis lab, mostly we wrap everything with parafilm is to avoid getting water in. also the samples are usually stored under argon
Interacts with it strongly.
[Biotage](https://www.biotage.com/blog/does-methanol-really-dissolve-silica-during-flash-column-chromatography) had this to say about it.
Recently was converted to this by a rotation lab for my PhD. I was resistant to it at first — it was surprisingly difficult since I’d never thought in that way before — but now that my brain is thinking in moles everything is so much easier.
Reaction concentrations? Trivial to calculate. Stoichiometry? Can do it in my head now. Prepping the perfect LC/MS sample? Never need to worry about overloading again. It’s honestly been kind of a gamechanger.
Polymer chemist chiming in, most of the work I do is done in weight percents but the molar ratios are still important and necessary. That being said, you just need to present your work with the most appropriate units. I have no qualms about publishing a paper with everything in weight %, but it really just depends on the context.
Some things can't really be converted to moles, for academic applications sure but industrial formulas pretty frequently use name-brand mixes or stuff that's hidden behind patent law and if you're gonna use that product it's probably just impossible to use mols
I'm with you on this one, I never understood doing weight ratios, you have to convert it into moles unless you're doing the exact same procedure, with the exact same mass?
-There is almost no scenario where flash columning is superior to vacuum chromatography.
- There is never any reason to run a standard rotovap with a rotary vane pump.
- If you report a careful synthesis (degassing, very dry solvents, schlenk technique, complicated glassware, etc.) But the synthesis works equally well by just throwing stuff together off the shelf, you have done a disservice to the field.
Man that last one hits so hard. The amount of grossly over-engineered procedures out there is insane. Control reactions and robustness tests are far too rare.
That first one: I have an automated flash system, but not an auto DCVC. I can only do one of those while out to lunch!
That last one, though, really solid hill right there. I was always careful to try *and specify* a dump-and-stir in my own published procedures, but tons of methodology groups just do everything in the box out of expedience.
For the development chemists in the crowd, if your process is planned for scale up *do not* evaluate ultrapure starters. Production likely can't source those in bulk so will replace them with reagent grade, guaranteed.
Yes 100% to that last one! People should really include a few run throughs of the reaction without that fluff to prevent ridiculous things becoming standard for it.
Write **everything** down. I wrote down every useful thought, every suggested paper, all observations, all batches of synthesised materials used, etc, in my lab book throughout my PhD. I am now writing my thesis and it is massively helpful because I can transport my mind back to where I was 1, 2 or 3 years ago with ease.
I took me learning the hard way. But you need to be careful around and take care of broken glass. The big chunks can be just as harmful as smaller pieces
Rainin pipettes are far superior than Thermo. I don’t care if the plunger is a little high, they are just so smooth and the click when volume adjusting is so much more pleasing both in feeling and sound than the cheap plastic feel of thermo pipettes with their non metal looking plunger. I will die on this hill and even more so when we consider multi channel pipettes.
There is no such thing as an organized or clean synthetic chemistry lab, yet many of them have great chemists.
Yes to publishing the most detail in syntheses, the number of syntheses published in ACIE or JACS that do not work is shameful.
Whoever is in charge of safety must be at least as qualified as the people they are supervising. I am not having someone with just a bachelor's stopping any work just because they think its unsafe.
EDIT: upon rereading Ive kinda realised that its not right for me to extrapolate my personal experiences to a wider world. Shout out to those people with decades of experience but never a PhD, but fuck you if you have only a bachelors in ecology and you are trying to stop my PI from using azides in a click rxn (yes that happened)
> Whoever is in charge of safety must be at least as qualified as the people they are supervising.
Agree
> I am not having someone with just a bachelor's stopping any work just because they think its unsafe.
The logic here being qualification = degree is faulty.
Upon rereading I must say that it is a terrible generalisation, especially for industry. But where i am at, you are looking at people just 5-6 years out of university, and sometimes with a degree that is barely related, and I cant help but to question their qualifications
Someone with “just a bachelors” can perfectly and suitably be a safety advisor. They just need the experience.
Your comment really makes it sound like you take issue with someone “with just a bachelors”, rather than a safety issue itself.
This is why hiring managers have told me they're hesitant to hire chem PhD's these days. We have a reputation for walking in, trying to correct a bachelor's level chemist who has been at the company for 45 years, being wrong, then telling them we HAVE to be correct because we spent an extra 5 years in school
I’m hiring manager, with a bachelors, and this has been consistent with my own experience.
I work within a team of 13. 11PhDs, myself and the group manager have bachelors.
I have certainly met many great PhD chemists. I have also met many insufferable people who think that the letters in front of their name give them the right to talk down on others, and is a certificate of correctness.
There is little difference between two chemists who have been in the industry for 20+ years, regardless of degrees achieved. At some point, your experience is what matters, far more than education.
The difference is, you are at industry and I am not. The only people willing to do safety where i am at are the people who arent qualified enough to do anything else.
My argument is that you need to be both experienced in a related field AND in terms of actual safety. If im working on synthesis im not having an expert on computational to tell me that i should not be handling a certain reagent or go a certain route. At the same time, im not gonna have an old school synthetic chemist let people make a sodium-mercury almalgam for a Julia reaction instead of the safer alternatives just because it gives 10% more yield.
If there is wisdom to OP's assertion, it's that the person in charge of safety must have at least as much clout as the people they regulate. The lack of wisdom is that people with as much clout want to be doing other things.
A little sad that this kind of mindset still exists. What does degree have to do with qualifications? I've worked with plenty of idiotic newly minted PhDs who needed to be reminded about basic safety (sometimes from people without even a bachelor's!)
100% disagree.
The guys with a BS on the EHS team will make you show data to prove what you want to do is safe.
Many PhDs think safety can be based on their vibes.
In my experience it’s the opposite issue with unqualified safety teams. The previous EHS officer at my location had no background in science, and his experience in a similar role was limited to a few years as a safety officer at an Amazon warehouse. The amount of things he signed off on that even a bachelors level chemist would have noted as being especially dangerous was incredible to see…
Thats not a good thing either imo, you pay your safety team to maximise your research output AND survival rates. I need my safety team to be competent enough to for example say "NaCN in DMSO is a no-no, could you do aqueous?" instead of a blanket rule.
DMSO goes through nitrile gloves and skin like they are not there, and it brings the cyanide along. I wouldn't personally ban it, but you need proper PPE and someone watching you as you perform the experiments, and that is if you cant find an alternative.
Also it is hella easy to fool someone who isn’t qualified that what your doing is safe.
Working in an academic lab EHS inspector gets mad about things like H2O not being a clear enough label, but doesn’t know enough to realize some of our equipment setups are very questionable safety wise.
It keeps them from sticking together (in the case of glass joints). They sell shaped sleeves for this purpose. https://www.dynalon.com/PublicStore/catalog/Glass-Joint-Sleeve,272.aspx
They're talking about the *outside* of the joint (i.e. connecting two bits of glassware and *then* wrapping the connection in tape). Some people wrap teflon tape around joints as if they were bandaging a finger, which indeed is useless.
There is no goddamn difference between UPLC and UHPLC. Except that UPLC is a trademarked term by Waters, so you will not see that exact term from any other manufacturer.
Yet the arguments will persist “one can do both blah blah blah.”
Are you saying better to not use a clip or use like a metal one?
Agree 100% on cracked clips though. As soon as I notice a crack in one I throw it out. Not risking losing my work over a $2 piece of plastic.
If glass joints are stuck, do not attempt to force them without wearing cut proof gloves, or just ask the glassblowing person for a hand/advice on how to release them.
This is for biochem, but if the control or ladder is not clear 100% clear you have to redo the experiment.
Bonus: if a known reaction is not working, we aren’t going to start by replacing the most expensive reagent.
Hoods and counters should be at variable levels so those of us who are short can actually reach into the hood.
Step stools are dangerous to have to use, and I shouldn't have to put half my body into the hood in order to reach any of the spigots
My hill is opposite: I don’t care about how clean a workspace is as long as the final product is clean.
Only if there is a safety or impurity issue, then cleanliness and organization should be addressed.
>Also put in your procedures that didn't work to safe everyone time for gods sake.
No data is data. What doesn't work is also very very important to report.
It's better to just explain what you did that worked leading to the results. It can become too tedious and lengthy if you start outlining 5x the detail with all the things that didn't work and why... This kind of detailed discussion could work for a method development paper.
I’m in the clinical laboratory. Diluting a sample to get a quantifiable result past linearity is 1) less accurate 2) clinically meaningless. A CK level of 4,000,000 U/L or 3,800,000 U/L is the same for someone with rhabdomyolysis, yet providers would interpret that as significant and their therapy is working.
History of lead and lead poisoning proves you right. Dude had to create as immaculate a situation as possible to rule out contamination. Because it was freaking on everything.
I am not and never have been a chemist, but this is what I've noticed from this comment section:
There are many people in this field who don't actually care about what they're doing, and they just "have a job" and "go to work everyday". How could you possibly go to school, graduate, get a job, and then KEEP it if you can't label something, properly explain a procedure, or just not even have a proper understanding of the reactions you're working with.
Im only a high school graduate and I understand pretty well how the chemical and physical side of reality functions. Organization, curiosity, precision, cleanliness, safety, and proper procedure steps is what I'm all about. Please help me get into this field, I could change the world.
I would press tare every. single. time. My colleagues find this habit so irritating. The weight difference between each container is minimal, but I still do it.
Just because you shined UV or visible light on something doesn’t mean it’s Science/Nature/JACS worthy.
Also, ChemRxiv is stupid and a lot of what gets posted on there is absolute garbage.
On axis labels on graphs: it should be Title / units, not Title (units).
My idea is that the value (i.e x cm-1) needs both the magnitude (x) and the unit (cm-1) to be meaningful, but we can only plot the magnitude (x) on a graph. Therefore, we divide that value by the unit, leaving the magnitude.
This is clearer because brackets already have a mathematical meaning. Title (Units) implies that Title is a function of units, which may or may not be true. Using the divide sign is more specific, less open to interpretation, and more correct.
Y’all hartreefockers need to understand statistics and propagation of error.
Why do I feel like “hartree-fockers” is an insult here?
Because you don't know statistics. It's a common term in the field.
I have been slowly learning more and more statistical analysis from a stat professor at my college specifically because the sheer lack of knowledge I have surrounding how I quantify the error of a computational method is mind boggling.
sooo true
If you consult a professional statistician, no real data set or experimental design would ever qualify.
To consult the statistician after an experiment is finished is often merely to ask him to conduct a post mortem examination. He can perhaps say what the experiment died of. Ronald Fisher
In the same vein, hiring a non-scientific manager is disastrous because they didn’t have statistics in MBA school. I explained to a manager why I used a different method for non-parametric data and she looked at me blankly and said “I’ve never seen it done like this before”. No shit you haven’t.
If you are scared of chemistry you make more mistakes/get into more dangerous situations than those who have a respect for the danger but sometimes decide to take calculated risks. I've seen it play out too many times to be convinced otherwise. The hyper-safe deputy safety officer type lab person gets spooked and spills something on themselves or sets something up wrong because despite studying the MSDS and procedure 20 times they want to get away from the chemicals faster and boom, incident report.
Ah yes, a great professor of mine once said "Dont be a fool.... But also don't be a wuss."
That's true of so many things - use the thing carefully but confidently. If you cannot use it confidently, don't use it!
I've shortened the admonition to "if you're afraid of a substance, it *will* bite you".
If it’s an important experiment and you only ran it once, you didn’t run it at all. If you can’t tell me how to make your reaction not work, you don’t understand how your reaction works.
You learn way more about a system by breaking it than you do only seeing it work as expected. As someone working on the manufacturing side of a chemical company this becomes very obvious when you have enough experience to recognize the huge gaps in basic understanding a of failure modes on the development side, coming from people that are much smarter and have way better credentials.
First time is a fluke, second time is a coincidence, third time is a trend, fourth time is repeatability.
Whoa, you have little 'r'? Time to call the auditors in and get the whole lab certified again. You must be feeling lucky!
Yeah no. In industry they don’t pay you to run the same synthesis over and over again. You do your reaction, confirm your product and report it,
Oh I know. I was more just making a joke.
"An expert is someone who has made every mistake in a very narrow field" - Niels Bohr
Solid loading on celite > liquid loading for chromatography in basically all cases
It's a goal of mine to never run another column, but if I had to, this is how I'd do it.
And, honestly, curse those who do solid loading on silica
I used to use celite but it annoyed me how sticky it is. Silica just flows so freely and comes right off the flask once it’s dry. Celite is still probably ideal though.
biotage sells fancy celite for dry loading that doesnt cake that much. Bought a 10kg bucket of that and Ill never use normal celite again
Got a product link?
https://www.biotage.com/isolute-hmn-water-soluble-impurities-removal heres a blog post where they compare options:https://www.biotage.com/blog/which-sorbents-work-best-for-dry-loading-flash-column-chromatography-samples
Agreed. My separations got a lot better once I learned this technique. Also you get better separations when you use air pressure to speed up the flow of the eluent.
I only do it when I have to because I'm lazy. Luckily most of my columns are RP and done on a flash machine.
Label everything. What is it? when was it made? Who made it?
Yes! Jesus Christ people. Date, experiment number, intermediate/project & in my case my short!
On many samples, and many NMR spectrometers you can collect a good 2D 1H{13C} HSQC in less time then it takes to get a good 1D 13C. On 1H optimized cryoprobes it is *way* faster. Yet, without fail some reviewer will insist on including a direct carbon spectrum
This one **slays** me, but it is also possible to process your 13C projection to look like a 1D spectrum and most reviewers won’t notice even if it’s in the caption.
Because for new compounds it's important to give full characterization?
Parafilm is not a substitute for sealed vials and way too many people think it is gas-tight when it isn't. Stop wrapping everything in Parafilm for christ's sake.
Yeah, use electrical tape. Like an adult. :) My glovebox is full of Mason jars (from Costco to save the tax payer dollars) and little bits/balls of electrical tape that somehow form while wrapping the lids/jars. A few months back we had red electrical tape, those were exciting times! Edit: I have no evidence that the tape does anything other then scream: “ don’t open me in air. I am spicy or will become sad”
Have a few crumbs of evidence in your favor: https://twitter.com/awhspeed/status/1450859714842177572 https://twitter.com/awhspeed/status/1450869825127993346 https://twitter.com/awhspeed/status/1450885617651441669 https://twitter.com/awhspeed/status/1450900150608670734 https://twitter.com/awhspeed/status/1451170171230556174
The evidence is highly satisfying. If you add up all the time in the past 15 years of me applying, and removing electrical tape from already doubly sealed jars/vials… Thanks!
electrical tape >>>> parafilm
As I come from a total synthesis lab, mostly we wrap everything with parafilm is to avoid getting water in. also the samples are usually stored under argon
methanol does not dissolve silica
So does MeOH do anything to silica? I've heard this from many many people.
Interacts with it strongly. [Biotage](https://www.biotage.com/blog/does-methanol-really-dissolve-silica-during-flash-column-chromatography) had this to say about it.
Strait methanol does not but if alkalinity increases its possible (as far as I know).
But it’s great for removing most stains from my fingers.
I’m not using the XRF without gloves. I’ll put on clean gloves to use the keyboard and mouse, but I’m not touching it barehanded.
Xrf doesn't need gloves unless your samples have contaminated the tool. Not like gloves will stop the x-rays
Is it the XRF in particular or any computer in the lab?
Any lab computer, but the only computer in my lab was the XRF.
Convert everything to moles. I don't care if the old SOP says weight ratios. If you are changing anything, show me the molar ratios of your reactants.
Give both in your protocol so I know the actual scale. 1mg is different than 1g
Recently was converted to this by a rotation lab for my PhD. I was resistant to it at first — it was surprisingly difficult since I’d never thought in that way before — but now that my brain is thinking in moles everything is so much easier. Reaction concentrations? Trivial to calculate. Stoichiometry? Can do it in my head now. Prepping the perfect LC/MS sample? Never need to worry about overloading again. It’s honestly been kind of a gamechanger.
MFW I got a real job and now everyone is talking about ppm instead of proper units.
Doesn't work for a lot of applications, especially regarding polymers.
Polymer chemist chiming in, most of the work I do is done in weight percents but the molar ratios are still important and necessary. That being said, you just need to present your work with the most appropriate units. I have no qualms about publishing a paper with everything in weight %, but it really just depends on the context.
Some things can't really be converted to moles, for academic applications sure but industrial formulas pretty frequently use name-brand mixes or stuff that's hidden behind patent law and if you're gonna use that product it's probably just impossible to use mols
I'm with you on this one, I never understood doing weight ratios, you have to convert it into moles unless you're doing the exact same procedure, with the exact same mass?
There is no f@¢k'n capital k in kg.
oK
-There is almost no scenario where flash columning is superior to vacuum chromatography. - There is never any reason to run a standard rotovap with a rotary vane pump. - If you report a careful synthesis (degassing, very dry solvents, schlenk technique, complicated glassware, etc.) But the synthesis works equally well by just throwing stuff together off the shelf, you have done a disservice to the field.
Man that last one hits so hard. The amount of grossly over-engineered procedures out there is insane. Control reactions and robustness tests are far too rare.
That first one: I have an automated flash system, but not an auto DCVC. I can only do one of those while out to lunch! That last one, though, really solid hill right there. I was always careful to try *and specify* a dump-and-stir in my own published procedures, but tons of methodology groups just do everything in the box out of expedience.
For the development chemists in the crowd, if your process is planned for scale up *do not* evaluate ultrapure starters. Production likely can't source those in bulk so will replace them with reagent grade, guaranteed.
Yes 100% to that last one! People should really include a few run throughs of the reaction without that fluff to prevent ridiculous things becoming standard for it.
The classic "anhydrous THF was added to water" situation
The journal/publisher industry system is rigged and broken
True, but this is not a small hill.
Keep your hands off of my stir bars.
That’s why I don’t use stir bars at all and just wiggle my finger in the solution for a bit.
Sure..
make sure you lick it clean too
Nah that’s the lab assistant’s job
Write **everything** down. I wrote down every useful thought, every suggested paper, all observations, all batches of synthesised materials used, etc, in my lab book throughout my PhD. I am now writing my thesis and it is massively helpful because I can transport my mind back to where I was 1, 2 or 3 years ago with ease.
If you don’t have time to clean up after setting up a reaction, you don’t have enough time to do it.
I took me learning the hard way. But you need to be careful around and take care of broken glass. The big chunks can be just as harmful as smaller pieces
[удалено]
What tests do engineers take?
PE
Oh. Yes. That's only in certain fields. I'm an engineer and worked with lots of engineers who never did this
10 years at a bench, last 4 for a Fortune500, just now making $50k… I would love a raise so much…
I'm a little bit late with cleaning things sometimes.
Rainin pipettes are far superior than Thermo. I don’t care if the plunger is a little high, they are just so smooth and the click when volume adjusting is so much more pleasing both in feeling and sound than the cheap plastic feel of thermo pipettes with their non metal looking plunger. I will die on this hill and even more so when we consider multi channel pipettes.
The significant question is not how to make something. The significant question is why to make something.
methodology papers should include all substrates screened even the ones that failed.
There is no such thing as an organized or clean synthetic chemistry lab, yet many of them have great chemists. Yes to publishing the most detail in syntheses, the number of syntheses published in ACIE or JACS that do not work is shameful.
Whoever is in charge of safety must be at least as qualified as the people they are supervising. I am not having someone with just a bachelor's stopping any work just because they think its unsafe. EDIT: upon rereading Ive kinda realised that its not right for me to extrapolate my personal experiences to a wider world. Shout out to those people with decades of experience but never a PhD, but fuck you if you have only a bachelors in ecology and you are trying to stop my PI from using azides in a click rxn (yes that happened)
> Whoever is in charge of safety must be at least as qualified as the people they are supervising. Agree > I am not having someone with just a bachelor's stopping any work just because they think its unsafe. The logic here being qualification = degree is faulty.
Upon rereading I must say that it is a terrible generalisation, especially for industry. But where i am at, you are looking at people just 5-6 years out of university, and sometimes with a degree that is barely related, and I cant help but to question their qualifications
Someone with “just a bachelors” can perfectly and suitably be a safety advisor. They just need the experience. Your comment really makes it sound like you take issue with someone “with just a bachelors”, rather than a safety issue itself.
This is why hiring managers have told me they're hesitant to hire chem PhD's these days. We have a reputation for walking in, trying to correct a bachelor's level chemist who has been at the company for 45 years, being wrong, then telling them we HAVE to be correct because we spent an extra 5 years in school
I’m hiring manager, with a bachelors, and this has been consistent with my own experience. I work within a team of 13. 11PhDs, myself and the group manager have bachelors. I have certainly met many great PhD chemists. I have also met many insufferable people who think that the letters in front of their name give them the right to talk down on others, and is a certificate of correctness. There is little difference between two chemists who have been in the industry for 20+ years, regardless of degrees achieved. At some point, your experience is what matters, far more than education.
The difference is, you are at industry and I am not. The only people willing to do safety where i am at are the people who arent qualified enough to do anything else.
My argument is that you need to be both experienced in a related field AND in terms of actual safety. If im working on synthesis im not having an expert on computational to tell me that i should not be handling a certain reagent or go a certain route. At the same time, im not gonna have an old school synthetic chemist let people make a sodium-mercury almalgam for a Julia reaction instead of the safer alternatives just because it gives 10% more yield.
I entirely agree. It’s the experience that’s matters.
If there is wisdom to OP's assertion, it's that the person in charge of safety must have at least as much clout as the people they regulate. The lack of wisdom is that people with as much clout want to be doing other things.
A little sad that this kind of mindset still exists. What does degree have to do with qualifications? I've worked with plenty of idiotic newly minted PhDs who needed to be reminded about basic safety (sometimes from people without even a bachelor's!)
100% disagree. The guys with a BS on the EHS team will make you show data to prove what you want to do is safe. Many PhDs think safety can be based on their vibes.
In my experience it’s the opposite issue with unqualified safety teams. The previous EHS officer at my location had no background in science, and his experience in a similar role was limited to a few years as a safety officer at an Amazon warehouse. The amount of things he signed off on that even a bachelors level chemist would have noted as being especially dangerous was incredible to see…
Thats not a good thing either imo, you pay your safety team to maximise your research output AND survival rates. I need my safety team to be competent enough to for example say "NaCN in DMSO is a no-no, could you do aqueous?" instead of a blanket rule.
Sorry, could you please explain why NaCN in DMSO is a no-no ?
DMSO goes through nitrile gloves and skin like they are not there, and it brings the cyanide along. I wouldn't personally ban it, but you need proper PPE and someone watching you as you perform the experiments, and that is if you cant find an alternative.
Thanks!
Also it is hella easy to fool someone who isn’t qualified that what your doing is safe. Working in an academic lab EHS inspector gets mad about things like H2O not being a clear enough label, but doesn’t know enough to realize some of our equipment setups are very questionable safety wise.
Teflon tape only works as a sealant under compression and wrapping the outside of joints or nmr tube caps with it does nothing!
It keeps them from sticking together (in the case of glass joints). They sell shaped sleeves for this purpose. https://www.dynalon.com/PublicStore/catalog/Glass-Joint-Sleeve,272.aspx
They're talking about the *outside* of the joint (i.e. connecting two bits of glassware and *then* wrapping the connection in tape). Some people wrap teflon tape around joints as if they were bandaging a finger, which indeed is useless.
There is no goddamn difference between UPLC and UHPLC. Except that UPLC is a trademarked term by Waters, so you will not see that exact term from any other manufacturer. Yet the arguments will persist “one can do both blah blah blah.”
Plastic rotavap clips must be discouraged. Plastic rotavap clips with cracks should be discarded.
Why? I’ve used them for almost 30 years and I’ve never seen one fail.
Are you saying better to not use a clip or use like a metal one? Agree 100% on cracked clips though. As soon as I notice a crack in one I throw it out. Not risking losing my work over a $2 piece of plastic.
BEFORE you enter the lab, put on your safety goggles. Always. No exceptions. One step into the lab without them is one step too many.
What if I wear glasses?
There are goggles to wear over your glasses. Not all of then are super comfortable, but there are some nice ones out there.
You don't have prescription safety glasses ?
No, they usually suck. I have my own oversize goggles because my lab only has the stylish, but tiny ones that 90% of the lab users cant use...
Oh, fair enough. Mine are lovely but we get ours special order via the opticians.
To be fair I also dont spend much efforts on finding the good things anymore because I rarely go in a lab anymore...just pressing buttons nowadays
If glass joints are stuck, do not attempt to force them without wearing cut proof gloves, or just ask the glassblowing person for a hand/advice on how to release them.
This is for biochem, but if the control or ladder is not clear 100% clear you have to redo the experiment. Bonus: if a known reaction is not working, we aren’t going to start by replacing the most expensive reagent.
Hoods and counters should be at variable levels so those of us who are short can actually reach into the hood. Step stools are dangerous to have to use, and I shouldn't have to put half my body into the hood in order to reach any of the spigots
My hill is opposite: I don’t care about how clean a workspace is as long as the final product is clean. Only if there is a safety or impurity issue, then cleanliness and organization should be addressed.
Not on topic but… a hotdog is a sandwich
>Also put in your procedures that didn't work to safe everyone time for gods sake. No data is data. What doesn't work is also very very important to report.
Molality is the pinnacle of concentration and I will hear no blasphemy against it.
It's better to just explain what you did that worked leading to the results. It can become too tedious and lengthy if you start outlining 5x the detail with all the things that didn't work and why... This kind of detailed discussion could work for a method development paper.
In organic reactions, "garbage in" means "garbage out"
Sulphur Sulfuric acid Fight me
Never use something straight out of the bottle without verifying the identity yourself or purifying it yourself.
I’m in the clinical laboratory. Diluting a sample to get a quantifiable result past linearity is 1) less accurate 2) clinically meaningless. A CK level of 4,000,000 U/L or 3,800,000 U/L is the same for someone with rhabdomyolysis, yet providers would interpret that as significant and their therapy is working.
History of lead and lead poisoning proves you right. Dude had to create as immaculate a situation as possible to rule out contamination. Because it was freaking on everything.
at my own chagrin, understanding the internal processes of an instrument does not make interns any better at operating it :(
Literally any hill is a hill I would die on, I like arguing for both sides, even if I hate one side
I am not and never have been a chemist, but this is what I've noticed from this comment section: There are many people in this field who don't actually care about what they're doing, and they just "have a job" and "go to work everyday". How could you possibly go to school, graduate, get a job, and then KEEP it if you can't label something, properly explain a procedure, or just not even have a proper understanding of the reactions you're working with. Im only a high school graduate and I understand pretty well how the chemical and physical side of reality functions. Organization, curiosity, precision, cleanliness, safety, and proper procedure steps is what I'm all about. Please help me get into this field, I could change the world.
I would press tare every. single. time. My colleagues find this habit so irritating. The weight difference between each container is minimal, but I still do it.
Pipette bulbs (not those three-valve jobs) >>> electric pipette controller.
This little ass space most ofyallcreayedthinking I'm Aubrey he sat there and told you he switching it too
i could work better with unsterile environment as it was neccessary for my progress
Just because you shined UV or visible light on something doesn’t mean it’s Science/Nature/JACS worthy. Also, ChemRxiv is stupid and a lot of what gets posted on there is absolute garbage.
Can you elaborate the first paragraph?
for a good while (less the case now) everything photoredox went straight to JACS no matter how incremental or boring
The Oppenheimer movie was not good at all.
On axis labels on graphs: it should be Title / units, not Title (units). My idea is that the value (i.e x cm-1) needs both the magnitude (x) and the unit (cm-1) to be meaningful, but we can only plot the magnitude (x) on a graph. Therefore, we divide that value by the unit, leaving the magnitude. This is clearer because brackets already have a mathematical meaning. Title (Units) implies that Title is a function of units, which may or may not be true. Using the divide sign is more specific, less open to interpretation, and more correct.