| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| gretchengehrke | "Hmm. This is surprising to me too. Iron-rich clay can readily adsorb arsenic under oxygen-rich conditions (this is actually the root of Bangladesh,..." | Read more » | about 6 years ago | |||
| gretchengehrke | "Hi @Ag8n, Do you know how the aquarium TDS meter works? Maybe it really is just a super cheap conductivity meter? " | Read more » | about 6 years ago | |||
| gretchengehrke | "@programmer1200, This is great! I agree with Chris and Holger that light scattering at a 90-degree angle is the standard approach for turbidity, an..." | Read more » | about 6 years ago | |||
| gretchengehrke | "Here's another resource for soil sampling procedures: https://archive.epa.gov/region9/toxic/web/pdf/ee-soilsampling-sop-env-3-13.pdf. " | Read more » | about 6 years ago | |||
| gretchengehrke | "Hi @Mempet, Could you use a turbidity tube like this one: https://www.carolina.com/environmental-science-water-quality/carolina-turbidity-tube-120-..." | Read more » | over 6 years ago | |||
| gretchengehrke | "That's such a good point @sarasage. That also ties into key elements about knowing your rights on public and private land and air space, states whe..." | Read more » | over 6 years ago | |||
| gretchengehrke | "@MadTinker, this is really exciting, and such important work for the promotion of community-collected data. Since the data streams you are discussi..." | Read more » | over 6 years ago | |||
| gretchengehrke | "Awesome, @Zengirl2. Thanks! " | Read more » | over 6 years ago | |||
| gretchengehrke | "Wow, thank you for this information @Zengirl2! Could you provide the paper citation here so we can look it up (since it didn't attach, and I honest..." | Read more » | over 6 years ago | |||
| gretchengehrke | "@donblair, I was just reading this again, and am again impressed by your elegantly simple approach -- such a great idea! It seems like this alterna..." | Read more » | over 6 years ago | |||
| gretchengehrke | "@bhikman, that integrated optical filter is neat, and surprisingly inexpensive! If you do pick this back up, I am super interested in seeing how we..." | Read more » | over 6 years ago | |||
| gretchengehrke | "Hi @bhickman and @ggallant! I was just reading this research note and comments again, and it sounds like such a promising project. Are there any up..." | Read more » | over 6 years ago | |||
| gretchengehrke | "That's so great, Shan! " | Read more » | almost 7 years ago | |||
| gretchengehrke | "@mienaikoe, This is so cool! How quickly can you process a liter of sea water? Also, you mentioned in your imgur post that you reversed the current..." | Read more » | almost 7 years ago | |||
| gretchengehrke | "@shanlter, this is great! Have you seen the spreadsheet on the www.publiclab.org/wiki/water-sensors page? There are some other options there listed..." | Read more » | almost 7 years ago | |||
| gretchengehrke | "Hi @MadTinker, oxidation-reduction potential (ORP) and power of hydrogen (pH) measure different chemical properties: ORP provides information about..." | Read more » | almost 7 years ago | |||
| gretchengehrke | "Interesting! At first I was wondering if the change in time-step occurred after the Riffle reached 0 deg-C, but then when I looked at your data tab..." | Read more » | almost 8 years ago | |||
| gretchengehrke | "Hi @bhickman, this is great. Other folks (mostly @donblair) have been working on developing a turbidity sensor too. I have a couple of questions wi..." | Read more » | almost 8 years ago | |||
| gretchengehrke | "Hey Don -- How well does the depth feature work? @stevie and I were just talking about it, and are needing a reminder. :) " | Read more » | about 8 years ago | |||
| gretchengehrke | "Hi Don, I was assuming the output would be in frequency for both, but there would be an algorithm before the graphing step to do a unit conversion,..." | Read more » | over 8 years ago | |||
| gretchengehrke | "Looks great! Two thoughts: (1) definitely important comment by Jeff about units and potentially a post-data-retrieval function for units conversio..." | Read more » | over 8 years ago | |||
| gretchengehrke | "Would it be useful for these folks to have balloon or kite mapping kits to take aerial photos of mine operations and expansions? " | Read more » | over 8 years ago | |||
| gretchengehrke | "Please post pictures in the comment section that are good example photos. I intend to put this information into a wiki page soon, and would love t..." | Read more » | over 8 years ago |