| Pages:
1
..
7
8
9
10
11
..
38 |
peach
Bon Vivant
Posts: 1428
Registered: 14-11-2008
Member Is Offline
Mood: No Mood
|
|
People who use things like SolidWorks can not only produce the CAD drawings of components, they can build them into huge assemblies, like buildings or
aeroplanes, and model each element for it's stress distribution as it goes through different frequencies (looking for natural resonance), loadings and
temperatures.
When you see places now that look like something out of SimCity, there's a good chance the entire plan for the railways, services, roads, municipal
facilities and residential buildings has been laid out in something like AutoCAD.
[Edited on 22-1-2011 by peach]
|
|
|
The WiZard is In
International Hazard
Posts: 1617
Registered: 3-4-2010
Member Is Offline
Mood: No Mood
|
|
Piranha bites
http://tinyurl.com/4svmllh
and :—
From: rtore00@pop.uky.edu (Professor Robert Toreki)
Newsgroups: sci.chem
Subject: Re: Piranha Solution
Date: 9 Apr 1997 14:00:06 GMT
In article <334A4298.C1C@lanl.gov>
"Rebecca M. Chamberlin" <rlmiller@lanl.gov> writes:
(snip)
> However, using it in an R&D lab is asking for trouble. A classic lab
> accident with piranha solution occurred at Cornell in 1986 or so. The
> grad students in one lab used to rotate responsibility for cleaning all
> of their glass frits by running piranha solution thru them (using "house
> vacuum") into a filter flask. One student made the mistake of leaving a
> trace of acetone in the flask. When the piranha solution hit the
> acetone, it went BLAMMO and a million pieces of glass embedded
> themselves into her face. Thank heavens she was wearing her safety
> glasses or she would most likely be blind now: the lenses in her safety
> glasses were shattered but still intact in the frames. The chemistry
> department took a photo of the glasses and used it in their "Are you
> wearing your safety glasses?" poster for years afterward. Not
> surprisingly, the student decided to leave chemistry after her
> hospitalization.
As it appears that Becky, I and others have not quite gotten the point
across, let me drive it home one more time. While you can usually tell
a conversation among chemists has gotten lame when they start swapping
lab accident stories, it is important that you **understand** that the
risk of using this solution is nowhere near the reward.
What Becky is writing about is 100% true. I saw it. It happened. It
could just as easily happen to you. Read this and then ask whether a
clean frit is worth this.
I was the first one to get to scene of the above incident. We heard a
sound like an M-80 (about a quarter stick of dynamite) from two labs
away. We got there within about 5 seconds to find her on the floor
halfway across the room surrounded by a large pool of blood. The
filter flask that she was using turned to dust; we never found a
fragment larger than about 2 mm even though it had been wrapped in
heavy black electrical tape. The metal 3 prong clamp that held the
flask sheared off at the point where it was clamped to the latticework
in the hood. A row of glass cabinets along one wall were peppered with
holes from the shrapnel. The lab had one of those 100 mm diameter
glass drainpipes running vertically on the wall opposite the hood
(about 8-10 m away) -- the pipe cracked in the middle ...we believe
that it wasn't from shrapnel, but from the compression wave of the
blast.
The student was wearing rubber gloves, a thick sweater, a lab coat, an
apron and safety glasses at the time of the explosion. The hood was
down part way and saved her from catching most of it in the face. The
arm holding the frit caught most of the damage -- the glove was
completely flayed and her arm had several hundred small bits of glass
in it as well as several fairly large lacerations. She had a wound
about 20 mm in diameter just next to her jugular vein. At least one
piece of glass went through her cheek. She (and everything else) was
also covered with hydrogen peroxide and sulfuric acid; something that
we didn't realize until much later because we had no way of knowing
what had happened. I think the bleeding stopped more because she went
into shock than from the pressure were were applying in two different
places.
She spent the next six hours having tiny bits of glass picked out of
her arm, neck and face. I'm told that you continue to have those work
their way out of your skin for the next several weeks after such an
incident -- that you sweep your good hand across the arm and cut
yourself on the glass sticking out of your own skin. This student had
some nerve/tendon damage and lost a bit of the motion in one or two of
her fingers; I can't recall if she had any hearing loss or not. All
things considered, she got off pretty lucky. And yes, she did leave
the program a short time after.
Now consider this: 10 minutes later and the rest of my research group
would have left for dinner. She was working ALONE in her laboratory,
"just cleaning up". Maybe she could have gotten to the phone on her
own...when I got there she was trying to get up, but not very
successfully. Ever try to stand up in a pool of your own blood and
sulfuric acid on a linoleum floor while dazed and injured? Me neither,
but it certainly didn't look very easy. Think about that the next time
you are working a late night alone.
The odd thing here is that if she hadn't been working alone there would
have been many other injuries in that laboratory. We found one large
chunk of glass imbedded in a bookcase over someone's desk. If the
owner of the desk had been there he would have caught this fragment
with the back of his neck. I can not stress enough how **stupid** it
is to put a desk or glovebox opposite a fume hood (or having a desk in
a lab, but that's not always avoidable). Look around your lab and see
if you have that configuration...it's scary. And the next time you see
someone without their safety glasses on, help them find a pair or make
them leave. It is one thing to be an innocent bystander, it is another
to be a stupid bystander.
BTW, the shattered safety glasses Becky is referring to were from a
separate accident at Cornell involving a vacuum line explosion, but
that's another story and I only know it secondhand. Part of their
rather effective campaign to make you think about safety.
Let me just end with the question I posed at the beginning: Were a
batch of clean frits really worth all this?
Rob
djh
----
…the Extreme Light Infrastructure ELI, designed to be the first
exawatt-class (10x18W) Laser. This gargantuan power will be
obtained by cramming a kilojoule ofo energy into a pulse only 10
fs in duration.
Mourou and Tajima
More Intense, Shorter Pulses
Science 331:41-42. 7I11
[Do to budget constraints – la laser will be use to treat toenail fungus on Weekends.]
[Edited on 27-1-2011 by The WiZard is In]
|
|
|
peach
Bon Vivant
Posts: 1428
Registered: 14-11-2008
Member Is Offline
Mood: No Mood
|
|
He's right, that is a lame story.
I can guarantee I'd get laughed out of a chemistry department for not knowing my mechanisms off by heart, yet I also rinse things with water, then
sulphuric prior to using Piranha.
| Quote: | The student was wearing rubber gloves, a thick sweater, a lab coat, an
apron and safety glasses at the time of the explosion. The hood was
down part way and saved her from catching most of it in the face. |
Classic 'pile on the safety gear and don't think' methodology at work.
The rubber gloves, apron, lab coat, and fume hood are in no way essential for using it. What they are doing is getting in the way and giving a false
sense of security. I've gone as far as making that video of me with it on my hands to demonstrate the point.
If you were to pick one piece of safety gear, it'd be for your eyes - in case it splatters. Forget steamy, tunnel vision, digging in, poor protection
goggles, get a face shield instead.
| Quote: | you can usually tell
a conversation among chemists has gotten lame when they start swapping
lab accident stories, it is important that you **understand** that the
risk of using this solution is nowhere near the reward. |
Erm... using it is perfectly worth the reward. There is not a lot else that will match it.
I notice for someone who doesn't like gore stories, but does want to ram home the risk, he didn't mention why she was using it or how to avoid it
doing what it did.
Pulling Piranha straight into a freshly used piece of glass under vacuum is simply unacceptable. It is the absolute worse case example. Okay, if it
was boiling it'd be worse, so it's second from the top. For a start, it may have been possible to clean the glass with something less dangerous.
But John! You'll make a mistake and regret it too some day!
Probably! And then I'll feel like a complete idiot. The one thing I'd like out of it wouldn't be people going on about blast radius's, but telling
other people how to stop it happening to them; even if that means getting laughed at when I post a photo of me in hospital. I also very
much appreciate help from other people, which this does not provide.
This accident would have been avoided if one of the staff (prior to handing them something that'd form high explosives in the glassware), had taken
30s to demonstrate what happens when you suck concentrated sulphuric through a damp frit.
As we see here, despite the mountain of safety gear, she was 'lying on the floor in a pool of blood'. Since she didn't have a full hazmat suit on,
it's lucky she wasn't doing anything toxic.
| Quote: | And the next time you see
someone without their safety glasses on, help them find a pair or make
them leave. It is one thing to be an innocent bystander, it is another
to be a stupid bystander. |
Whoever let the students use it unsupervised should leave. And the person who recommended using it before anything else. And the person who suggested
immediately connecting the sintered glass to the vacuum.
And the person going on about goggles rather than pointing these things out.
Something has gone seriously wrong here. Either Becky didn't care, or someone didn't care about her.
----------------------------------------
Cleaning frits
Try solvents and biological detergents first (soaking overnight)
Not working?
Rinse with water, then try sulphuric
Not working?
Try piranha (DO NOT rinse the glass with solvent between the last stage and this, for the above reason)
Alternatives?
Nital / cook the sinter (preferably with oxygen) near 500C / alkaline peroxide (it will start rotting sintered glass) / use a disposable
membrane filter instead and save yourself the effort of cleaning glass frit (I am quite surprised more of these aren't used in chemistry)
READ THIS AND THE COMMENTS
Take the points about lab coats and gloves as significantly less than the one about rinsing the funnel first. He's only suggesting using the fume hood
to provide a barrier between you and glass, which a plastic shield will do or not standing in the room with it.
Do not do as he suggests and connect it to the vacuum until it's at least fully permeated the frit. Better yet, let it run through once without the
vacuum - as someone suggests in the comments.
[Edited on 27-1-2011 by peach]
|
|
|
ScienceHideout
Hazard to Others
Posts: 391
Registered: 12-3-2011
Location: In the Source
Member Is Offline
Mood: High Spin
|
|
Once my friend wanted to see my lab. I sail what the hell and I took him. He asked me what a certain chemical was. It was on my ring stand in a 19/22
quickfit flask with a stopper in it. I said I really need to get it down and put in on a cork ring. I asked him to hold it while I get a ring out. A
few seconds later I turned to the sound of broken glass. He had an Oh, **** look on his face and the stopper in one hand, while my reagent was eating
away the floor. I quickly turned and grabbed baking soda and poured it all over.
It was the corrosive dragendorff reagent.
From that point on NO ONE but me was allowed in my lab.
hey, if you are reading this, I can't U2U, but you are always welcome to send me an email!
|
|
|
cyanureeves
National Hazard
Posts: 744
Registered: 29-8-2010
Location: Mars
Member Is Offline
Mood: No Mood
|
|
today i was making sodium nitrate with cold packs and bubbling the ammonia into distilled water.it was doing great until it just stopped bubbling even
though it was boiling,so i lifted the tube out of the water and some of it got sucked back into the sodium hydroxide/ cold pack mix. i got weak
ammonium hydroxide now, my favorite ammonia generator (round pyrex coffee pot with narrow neck)in pieces,a smelly tool shed and no sodium nitrate.i'm
going back to my old way of making ammonium hydroxide by capping a coffee pot with an inverted plastic container with a hole in the cap and a piece of
2" p.v.c. tube in it a just collect the condensate. i loved that pot!
|
|
|
plante1999
International Hazard
Posts: 1936
Registered: 27-12-2010
Member Is Offline
Mood: Mad as a hatter
|
|
Quote: Originally posted by ScienceHideout  | Once my friend wanted to see my lab. I sail what the hell and I took him. He asked me what a certain chemical was. It was on my ring stand in a 19/22
quickfit flask with a stopper in it. I said I really need to get it down and put in on a cork ring. I asked him to hold it while I get a ring out. A
few seconds later I turned to the sound of broken glass. He had an Oh, **** look on his face and the stopper in one hand, while my reagent was eating
away the floor. I quickly turned and grabbed baking soda and poured it all over.
It was the corrosive dragendorff reagent.
From that point on NO ONE but me was allowed in my lab. |
you'd need a friend who shares the same passion as you. I'm lucky I have one, in some of my video on my youtube channel I have three arms .... my
friend take very care of my stuf and my glassware , probably more than my.
[Edited on 14-3-2011 by plante1999]
[Edited on 14-3-2011 by plante1999]
I never asked for this.
|
|
|
redox
Hazard to Others
Posts: 268
Registered: 22-2-2011
Location: The Land of Milk and Honey
Member Is Offline
Mood: Chalcogenetic
|
|
I had a beaker full of boiling conc. acetic acid. There was a small crack I noticed previously (but ignored), which, of course, shattered as it was
heating and spilled the acid EVERYWHERE. My basement smelled like hell's vinegar for weeks.
|
|
|
The WiZard is In
International Hazard
Posts: 1617
Registered: 3-4-2010
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by redox | I had a beaker full of boiling conc. acetic acid. There was a small crack I noticed previously (but ignored), which, of course, shattered as it was
heating and spilled the acid EVERYWHERE. My basement smelled like hell's vinegar for weeks.
|
I remember a bunch and a half years ago decided to make
sauerbraten. The Joy of Cooking sez — Heat but do not boil:
Equal parts of mild vinegar and water
1/2 cup sliced onion
2 bay leaves
1/4 cup sugar
Pour this mixture while hot over the beef....
I didn't have a pot large enough to hold the eye round
so I used a plastic bag... whose seams lasted all of 3-seconds
before seperating... my kitchen smell like a deli for two weeks.
And byda --- when cleaning squid ... don't squeeze them or
you will end up with ink all over the kitchen.
Now back to science .... I would note in passing :—
Harold McGee
On Food and Cooking : The Science and Lore of the Kitchen
Simon & Schuster 1984
684 Pages
djh
----
Rötgen's [William Conrad] parents were
greatly concerned about their future
daughter-in-law. [Swiss -Bertha Ludwig]
They had seen that she was an intelligent
girl and had a good education, but they also
recognized that she was not fully prepared
to enter matrimony. Her faults, however,
could quickly be corrected, and so it was
mutually decided that Bertha should go to
Apeldoorn to learn not only the rudiments
of a German household but also how to cook
certain German and Dutch style dishes that
their son especially liked.
W Robert Nitske
The Life of Wilhelm Conrad Röntgen : Discovery of the X Ray
U of Arizona Press 1971
[Edited on 29-3-2011 by The WiZard is In]
[Edited on 29-3-2011 by The WiZard is In]
|
|
|
redox
Hazard to Others
Posts: 268
Registered: 22-2-2011
Location: The Land of Milk and Honey
Member Is Offline
Mood: Chalcogenetic
|
|
Did you test the chemical properties of the squid ink, by any chance?
|
|
|
Mixell
Hazard to Others
Posts: 449
Registered: 27-12-2010
Member Is Offline
Mood: No Mood
|
|
Just broke my LAST beaker (the fifth one), good that they are quite cheap, although that means that I'll need to visit the glassware store again...
|
|
|
Jor
National Hazard
Posts: 950
Registered: 21-11-2007
Member Is Offline
Mood: No Mood
|
|
I hardly every break glassware. In my 4 years of amateur chemistry, I broke 1 erlenmeyer, about 4 beakers and a vacuum allonge. But even then, when
you break something it really sucks. Beakers would not be much of a problem as they are cheap but i would hate to break 3-necks, condensors, and such
glasware.
|
|
|
Arthur Dent
National Hazard
Posts: 553
Registered: 22-10-2010
Member Is Offline
Mood: entropic
|
|
Yeah, it's been a while since I broke something. Occasionally, I break test tubes but these are so inexpensive that it doesn't count. I have broken a
nice 500 ml beaker by dropping a tiny piece of metallic lithium in water and not stirring. The tiny piece bubbled and melted until it reached the side
of the beaker and spontaneously caught fire, instantly cracking the whole beaker and melting a hole right through the glass!
Right now I have a beautiful Friedrich condenser that has a 1/2 inch crack on the water intake port, I have no idea how and if it can be repaired so
right now, it's just a decoration.
I have thrown away a nice 250 ml boiling flask because I noticed there was a chip of glass 5x5 mm missing at the bottom INSIDE the vessel!  Must be that it was heated too strongly or something...
Robert
--- Art is making something out of nothing and selling it. - Frank Zappa ---
|
|
|
#maverick#
Hazard to Others
Posts: 209
Registered: 7-4-2011
Member Is Offline
Mood: hybridised
|
|
i broke my only 3 necked RBF and a Erlenmeyer with the little vaccum port on the side in the last 2 weeks, both in careless ways i was pissed
|
|
|
nezza
Hazard to Others
Posts: 324
Registered: 17-4-2011
Location: UK
Member Is Offline
Mood: phosphorescent
|
|
Many year ago when I was at school I found out how to make nitrogen tri-iodide so I had a go at it. Made a small amount at home and left the filter
paper to dry overnight on a saucer. Next morning I poked it with a stick to see if it was dry. It was and blew up in my face. It smashed the saucer to
pieces and I was lucky that the only injury I got was a speck of iodine in my eye which stung like hell.
I also blew up some potassium permanganate and red phosphorus in a pestle and mortar around the same time when I
a. could get hold of the reagents easily
b. Didn't know just how dangerous this could be
Fortunately it was a very small (well under 1 gram) amount so it just went bang and didnt break anything.
So a bit of luck is always helpful with chemistry.
|
|
|
#maverick#
Hazard to Others
Posts: 209
Registered: 7-4-2011
Member Is Offline
Mood: hybridised
|
|
| Quote: Originally posted by nezza | Many year ago when I was at school I found out how to make nitrogen tri-iodide so I had a go at it. Made a small amount at home and left the filter
paper to dry overnight on a saucer. Next morning I poked it with a stick to see if it was dry. It was and blew up in my face. It smashed the saucer to
pieces and I was lucky that the only injury I got was a speck of iodine in my eye which stung like hell.
I also blew up some potassium permanganate and red phosphorus in a pestle and mortar around the same time when I
a. could get hold of the reagents easily
b. Didn't know just how dangerous this could be
Fortunately it was a very small (well under 1 gram) amount so it just went bang and didnt break anything.
So a bit of luck is always helpful with chemistry. |
djust a bit of luck is an understatement, about 2 or 3 years back i read the anarchists cook book and made tiiodide before i knew anyrthing about chem
and how sensitive the compound is, it went boom right in my face thank good i had goggles, gloves and a small amount, i was scared shitless
|
|
|
redox
Hazard to Others
Posts: 268
Registered: 22-2-2011
Location: The Land of Milk and Honey
Member Is Offline
Mood: Chalcogenetic
|
|
About a week ago I bought a 10 mL volumetric flask (more as a joke) on the cheap. Three days after I got it, it fell and shattered. $4 wasted dollars.
My quite small but growing Youtube Channel: http://www.youtube.com/user/RealChemLabs
Newest video: Synthesis of Chloroform
The difference between chemists and chemical engineers: Chemists use test tubes, chemical engineers use buckets. |
|
|
#maverick#
Hazard to Others
Posts: 209
Registered: 7-4-2011
Member Is Offline
Mood: hybridised
|
|
| Quote: Originally posted by redox | | About a week ago I bought a 10 mL volumetric flask (more as a joke) on the cheap. Three days after I got it, it fell and shattered. $4 wasted dollars.
|
May your flask and my flask rest in peace in heavens meth lab 
|
|
|
Magpie
lab constructor
Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline
Mood: Chemistry: the subtle science.
|
|
Today I had to change out a 4' (1.3m) fluorescent light bulb for the lab. I assumed it would have to be broken before placing in the garbage can.
Never having done this before and not stopping to realize that it was under vacuum I gave it a whack near one end with a pair of channel locks.
Luckily I was wearing leather gloves and had my lab goggles on as there was a violent implosion with glass flying everywhere and a white powder
shooting out the open end, pointed away from me. Checking with my son, who has broken many such bulbs at his business, he said that he places them in
a garbage bag before breaking. He just assumed that I knew that so hadn't mention it beforehand.
The single most important condition for a successful synthesis is good mixing - Nicodem
|
|
|
Bot0nist
International Hazard
Posts: 1559
Registered: 15-2-2011
Location: Right behind you.
Member Is Offline
Mood: Streching my cotyledons.
|
|
Late last night I was setting up to run a 10g synthesis of TNP, a reaction I have done many times safely. I had an oil bath set up on my table on a
towel and it was heating up to 85c. While the bath was warming I was diluting my 98% H<sub>2</sub>SO<sub>4</sub> to 40ml of
92%. During the dilution I somehow pulled the cord to my oil bath and the liter of warm oil hit the floor. Let me tell you that a liter on the
linoleum look like the gulf oil spill, so I rushed to get towels.
While I was sopping up the oil I noticed an acrid burning smell and then noticed that the 30 or so milliliters of the warm
H<sub>2</sub>SO<sub>4</sub> had spilt onto the towel on top of the table. What was left by the time I noticed was a pile of
smoking black carbon. After neutralizing and cleaning up the mess I was left with an ugly blemish on my table the size of a dinner plate. Good times!
U.T.F.S.E. and learn the joys of autodidacticism!
Don't judge each day only by the harvest you reap, but also by the seeds you sow.
|
|
|
The WiZard is In
International Hazard
Posts: 1617
Registered: 3-4-2010
Member Is Offline
Mood: No Mood
|
|
Bromine
FOUR INJURED IN OHIO UNIVERSITY CHEMICAL BLAST
400 Students Routed by Bromine Fumes.
Chicago Daily Tribune (1923-1963) - Chicago, Ill.
Date: Feb 11, 1931
Start Page: 16
Pages: 1
Text Word Count: 405
Abstract (Document Summary)
[Special.]--An instructor was seriously burned, two graduate
assistants and a co-ed overcome, and more than 400 students
routed from the chemistry building at Ohio State university today
when a five pound bottle of liquid bromine exploded, when it fell.
---
Amazing how many thing explode.
|
|
|
The WiZard is In
International Hazard
Posts: 1617
Registered: 3-4-2010
Member Is Offline
Mood: No Mood
|
|
Exploding bromine too!
From the NY Times
Attachment: Chem Bromine Ohio NYT.pdf (16kB)
This file has been downloaded 747 times
|
|
|
plante1999
International Hazard
Posts: 1936
Registered: 27-12-2010
Member Is Offline
Mood: Mad as a hatter
|
|
so... bromine can explode , I have dificulty to see how it can explode , it dont have instable bonds....
[Edited on 27-5-2011 by plante1999]
I never asked for this.
|
|
|
The WiZard is In
International Hazard
Posts: 1617
Registered: 3-4-2010
Member Is Offline
Mood: No Mood
|
|
That Devil Bromine - redux
From the NY Times
Attachment: Chem Bromine Brookhaven.pdf (54kB)
This file has been downloaded 790 times
Attachment: Chem Bromine Woman chemist.pdf (20kB)
This file has been downloaded 803 times
|
|
|
Mailinmypocket
International Hazard
Posts: 1351
Registered: 12-5-2011
Member Is Offline
Mood: No Mood
|
|
I have been unpacking my chemistry equipment while getting back into the hobby lately, last night out came my box of "nicer more specialized"
glassware...first thing that goes flying on the floor is my nice 100 ml weighing bottle with ground glass stopper and all... Thouroughly insulted... I
dropped what i was doing and decided to browse Sciencemadness while having a beer lol ... I guess it could have been a condenser or a retort...
but....still it was my only one.
|
|
|
redox
Hazard to Others
Posts: 268
Registered: 22-2-2011
Location: The Land of Milk and Honey
Member Is Offline
Mood: Chalcogenetic
|
|
Yesterday my really nice (and expensive) 14/20 200 mm vigreux column hooked on my lab coat as I stood up, one end of the column rose about an inch,
and fell back to the table, breaking. 
My quite small but growing Youtube Channel: http://www.youtube.com/user/RealChemLabs
Newest video: Synthesis of Chloroform
The difference between chemists and chemical engineers: Chemists use test tubes, chemical engineers use buckets. |
|
|
| Pages:
1
..
7
8
9
10
11
..
38 |
![[*]](images/xpblue/default_icon.gif){kind=icon}
