| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| Ag8n | " The United States pharm. had a lot of tests for lead and other elements( like arsenic and barium). You can't argue with its scientific validity- ..." | Read more » | about 5 years ago | |||
| Ag8n | " My mistake, it chemiluminesces in the red, not the blue. Sorry about that. " | Read more » | about 5 years ago | |||
| Ag8n | " I've used ion chromatography(IC) to analyze for a number of ions, including nitrate and nitrite. The new instruments dedicated to IC are much bet..." | Read more » | about 5 years ago | |||
| Ag8n | " Don't know exactly how you want the spreadsheet fille d in on edxrf. I have used it extensively, in an r&d environment. I've only used a han..." | Read more » | about 5 years ago | |||
| Ag8n | "Warren got most of the problems with kjeldahl. Here are a few more. Kjeldahl testing takes some specialty glassware. It's not terribly hard to l..." | Read more » | about 5 years ago | |||
| Ag8n | " The only other thing to point out- all these calculations assume the particles are spheres. We had particle surface area measuring equipment. T..." | Read more » | about 5 years ago | |||
| Ag8n | " On pcbs (it's the chlorine part I 'm worried about, here), whenever you put a chlorine containing material in a flame, the flame should turn green..." | Read more » | about 5 years ago | |||
| Ag8n | " From a quick look, it seems that PAHs and PNAs (polynuclear aromatic hydrocarbons) are the same thing. We did PNA analysis on carbon black that w..." | Read more » | about 5 years ago | |||
| Ag8n | " You can buy the instruments with a microprocessor attached. All you have to do is take a syringe, put the liquid in the glass tube, and it will r..." | Read more » | about 5 years ago | |||
| Ag8n | " The reason multimeters aren't used for measuring the resistance of a solution is polarization. It's a fancy word, but by passing direct current t..." | Read more » | about 5 years ago | |||
| Ag8n | " You might want to look into ANDalyze. They use a new technology based on DNA for heavy metal analysis in water samples. I'd need to see validati..." | Read more » | about 5 years ago | |||
| Ag8n | " First off, spectrometers are much more common than spectrophotometers, these days. And cheaper too. T he method you referenced relies heavily on..." | Read more » | about 5 years ago | |||
| Ag8n | " I've used a version of this method. We used it for lead and just for visual comparison. There was a link for it but it wouldn't work. It was th..." | Read more » | about 5 years ago | |||
| Ag8n | " I'm downloading it now. Give me a day or two to go through it. Thanks! " | Read more » | about 5 years ago | |||
| Ag8n | " A good step forward. Congratulations! Maybe @falbriard could use these ideas for some of his work. " | Read more » | about 5 years ago | |||
| Ag8n | " There are plenty of ways to monitor it. Most importantly of them are expensive. The sulfur smell was probably hydrogen sulfide. There are some d..." | Read more » | about 5 years ago | |||
| Ag8n | " You might be able to find some thing. Let's take it step by step. First, the only one of those metals that has any color in the Vis is chromium. ..." | Read more » | about 5 years ago | |||
| Ag8n | " If you can afford it, you can take air samples and then later inject them into a gas chromatograph/mass spectrometer (GC/MS). Couple that with a ..." | Read more » | about 5 years ago | |||
| Ag8n | "I know it's expensive, but the quickest heavy metal monitor is to dry the soil and do X-Ray flourescence (XRF). After that, there are many set che..." | Read more » | about 5 years ago | |||
| Ag8n | " First, using a spectrometer in the visible range ,by itself, normally isn't possible. You normally have to add chelating agents to make the metal..." | Read more » | about 5 years ago | |||
| Ag8n | " Normally, in an open location, the national weather service (NWS) wind direction would be ok. But as you get into more urban locations, where bu..." | Read more » | over 5 years ago | |||
| Ag8n | " There are several manufacturers of handheld XRF analyzers. And yes, they are usually cost limited. The cost can be reduced somewhat by renting, i..." | Read more » | over 5 years ago | |||
| Ag8n | " The kits for these tests ( someone correct me if I'm wrong) appear to be made by RenekaBio. A quick look down the test procedure and method showe..." | Read more » | over 5 years ago | |||
| Ag8n | " Can you give me the reference ( e.g.Lehninger)? I'd like to look it up. Regards " | Read more » | over 5 years ago |