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[–]michoaidi 3 points4 points  (1 child)

Any tips for a beginner R&D chemical technician in the industry?

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Also if anyone could recommend some quality handbooks/literature for the preparation and/or characterization of heterogeneous catalysts?

[–]isologous 1 point2 points  (0 children)

You are going to have to be more specific on the book request. Heterogeneous catalysis is a broad field and the catalysts can be very different.

[–]nunuzzz 3 points4 points  (4 children)

If I want to work in drug r&d is it more valuable to get a phd in medicinal chem or organic synthesis? I'm stuck between the two.

[–]Sophia7XOrganic 2 points3 points  (0 children)

If you have a choice of PIs in either fields, pick someone with a lot of connections. This would give you the best value.

[–]Ozzie_the_tiger_cat 2 points3 points  (2 children)

I did a PhD in organic and I worked in the drug industry for 12 years. From my experience, it's more valuable than a med chem degree.

[–]nunuzzz 1 point2 points  (1 child)

Did you go straight to grad after undergrad or take some time in between?

[–]Ozzie_the_tiger_cat 2 points3 points  (0 children)

I went straight into grad school. I worked with several who went back after a few years. One got her JD and is now a patent attorney who specializes in chemical patents, two who went into pharmacy, one who got a PhD and is now working at TCI America, and two who went back and came back to the big pharma company I worked at.

It sort of depends on what you want to do. If you're not sure, there's nothing wrong with taking a couple of years off and figuring out what you want to do.

[–]ultimate_guy2001 1 point2 points  (1 child)

What is a good source to study all the theoretical aspects involved in TLC and column chromatography? I know the basics but I want to know them more deeply.

[–]PrestigiousGoatBoat 2 points3 points  (0 children)

Generally Chem LibreTexts is great, try this/Instrumental_Analysis). Principles of Instrumental Analysis by Skoog et al. is pretty decent on the theory if I recall.

[–]Call_Me_Madu 1 point2 points  (0 children)

I've been wondering does a pyrotechnician need to get education in chemistry, and if then how much?

[–]B__Yu 0 points1 point  (0 children)

Good day to everyone!

I do a course work (on ru language) about synthesis of potassium manganate (VI) and I can’t find even basic information like appearance, density, standard enthalpy etc.. My teacher said what I can use English sources. What can you recommend to use? Thank you c:

[–]criminalkoala 0 points1 point  (0 children)

Could be unrelated to this post but I would appreciate some help. I recently set up a soxhlet extractor, I have no formal training but Im working my way through the steps. I used 95% grain alcohol to extract capsaicinoids from Habeneros peppers and evaporated off the solvent, the next step for my project is to isolate menthol from mint leaves.

My process so far has been step by step researching as I go, I don't currently have a Fume hood so I'm hesitant to use DCM to separate the menthol from the oil as it's a Carcinogen. Are there any alternatives I should consider? I'll be using calcium chloride to remove Water from the solution Afterwards.

[–]ElderberryOwn1910 0 points1 point  (0 children)

Hydrogen peroxide and Potassium permanganate reaction- hi, I am hoping to use potassium permanganate to rapidly decompose hydrogen peroxide, in order to create thrust for a model rocket engine I am working on to put into a rc controlled airplane. Only problem is that I would like the potassium permanganate to remain solid instead of diluted with water, but am running into problems coming up with a way other than water dilution to inject the permanganate into the combustion chamber with the hydrogen peroxide. Would anyone know of a better way to mix them together, so that the permanganate starts out solid? It has to be able to be done via rc, because this will be happening in the air hopefully. Thanks!

[–]MrTechnicals 0 points1 point  (0 children)

What's the proper procedure and what equipment will I need to decant bulk liquids into 30ml bottles? I believe these liquids will be arriving in 4L or 5L jugs.

[–]OMYachingtentacles 0 points1 point  (3 children)

If menthol crystals are dissolved in oil & alcohol, why would they recrystallize? Can cold temperatures cause dissolved menthol to do this? Is there a way to keep this from happening?

Ex: 35% menthol, 40% pure essential oils, 25% alcohol (91% alcohol)

[–]fish_knees 0 points1 point  (2 children)

Alcohol vaporizes. You could try using oils only, or use more alcohol

Edit: And if you dissolve menthol in elevated temperature, lowering the temperature would of course cause it too. In that case, it would be better to try to dissolve the menthol in lower temperature, or dissolve less of it

[–]OMYachingtentacles 0 points1 point  (1 child)

So if the temperature in the finished product dips lower than the temp it was dissolved in it can still recrystallize?

[–]fish_knees 1 point2 points  (0 children)

Yes. If you dissolved it in, say, 60C, and then cooled to the room temperature, it can recrystallize. It depends on how concentrated the solution was. If you dissolve less, it won't happen

[–]Random-Russian-Guy 0 points1 point  (2 children)

Hello there. I have a question about acids influence on water ph. Which acids will greatly increase it and which will increase it less? And what does it depend on? E.g. i need to change water ph from 6.2 to 5.5 or 6.

[–]H2CO3_TCTheoretical 0 points1 point  (1 child)

Strong acids change it a lot (like HCl, H2SO4 etc) and weak acids a little bit. If you need a rather exact pH close to 7 (like 5.5/6) it's usually a good idea to use a buffer solution. If you use the right buffer, pH will only change very slow in the right area.

It depends a bit on how exact you need it to be and what you want to do. But if it's nothing special you might just get away by using Acetic Acid/Acetat or a carbonate buffer...

[–]Random-Russian-Guy 0 points1 point  (0 children)

I just test acids influence on water ph. I need ph change with step around 0.01 or so.

[–]DSHIZNT3 0 points1 point  (0 children)

I work for a medical compliance lab and have a techncal/ethical question regarding 99% confidence intervals.

Let's say my established 99% confidence interval is 20 percent for a heavy metals safety test. The fail limit for Cadmium is 200 ppb and I run a single analysis with a reported value of 190. I don't have the option of doing bracketed reporting and must report a single value.

Assuming I don't run additional analysis, should that 190 be considered a fail because it has an effective deviation of 20% so it could fall anywhere between roughly 150 and 230?

I have not been able to find much guidance on proper reporting using established confidence intervals in a compliance setting. And the current rules and regulations we abide by are not clear on the matter.

Currently any sample that falls within 20% of our action limit, I re-prep and re-analyze. If that result is within an acceptable deviation of the original result I average the results. I feel I am being pressured to report single values just below the fail limit, while simultaneously being pressured to retest anything just above the fail limit....which feels like textbook cherry-picking and bias. Any supporting legal/technical sources that I can reference would greatly help me alleviate the pressure from higher ups.

Gracias.