Precipitation - Science method
. Precipitation occurs when a local portion of the atmosphere becomes saturated with water vapour, so that the water condenses and "precipitates," in the form of rain, drizzle, sleet, snow, graupel, or hail.
Questions related to Precipitation
I am trying to extract gDNA from culturable endophytes isolated from Gum trees but have not been getting good result from the protocol attached. The endophytes are pigmented.
I used mycelia of endophytes cultured in broth. After centrifuge of precipitation step, the DNA pellete was contaminated with dark colour (dark pellete). So I did not proceed further.
I than repeat the extraction but this time I ground mycelia in liquid nitrogen and use the same extraction protocol. I obtained white precipitated DNA pellet unlike the previous one. Then I dissolved DNA pellete in milliQ water. The NanoDrop readings were well below A260/230 and DNA yield was very poor.
If anyone/experts of endophytes can help me with DNA extraction advice.
I am using fresh mycelia of endophytes cultured in both broth and on solid agar. Both still hasn't yield good result.
DNA extraction protocol attached.
Which type of cloud is most likely to produce precipitation and process in which any product of condensation of atmospheric water vapour falls under gravity?
Antimicrobial material which is insoluble in water. When I dissolve in DMSO and diluted it with water(%10), it precipitated in the bottom of the tube. how can I use material for antimicrobial test?
I have experience in studying the impact of hydrogeology on catastrophic floods. An example would be the flooding in Europe in the summer of 2002. See my discussion "How is geodynamics and hydrogeology taken into account?". see my publication "Floods and droughts as a result of deformability of the geological environment" for details.
The water content of the rivers is formed by atmospheric precipitation and underground waters. Influence of underground waters on water content of the rivers cannot be measured. It is shown that the volume of underground water exchange is underestimated and can be commensurable with a volume of atmospheric precipitation. Change of level of underground waters is defined by changes of volume of the geological environment during geodeformations. It is offered to consider geodeformations as one of the reasons of floods and droughts. Studied the changes the gravitational field and geodeformations during droughts and floods in the Amazon in 2005-2006. Studied the hydrological regime of the River Nile. Shows the influence of geodeformation on the level of Danube and Dniester. Proposed detailed study the causes of floods in Europe in 2002. Influence of the Earth’s surface deformation on floods and droughts is very important and requires special detailed study. Changes in volume of rocks during Earth's surface deformation are accompanied by dilatancy which influence on the amount of drought and flooding has turned out to be significant. Study of the processes considered in the thesis gives grounds to expect that floods and droughts associated with deformations of the geological environment will be successfully predicted. Foto https://www.google.com/url?sa=i&url=https%3A%2F%2Fren.tv%2Fnews%2Fv-mire%2F1138805-v-chernomorskom-regione-turtsii-livni-vyzvali-navodneniia&psig=AOvVaw2SdhsJ2lm16vYlBvplRoZX&ust=1694020292799000&source=images&cd=vfe&opi=89978449&ved=2ahUKEwjyktC_-5OBAxWdEBAIHSPSCyEQr4kDegQIARBc
I have a sample in the dissolved state. Acetone acts as an anti-solvent to precipitate the substance from the DMSO solution. However, the recovery yield is low. Is there any method to collect the samples in maximum yield?
Filtration can't be used as it will decrease the yield. I'm using centrifugation, to collect the samples now. Does anybody have any suggestions?
I am producing a flocculent precipitate when doing free radical polymerization of itaconic acid in aqueous solution, what should this substance be? How is it produced?The initiator is sodium persulfate at five percent of the total reactants, and the reaction temperature is 80 ℃.
With the help of standardized Precipitation Evapotranspiration Index how we get return period of drought?
We synthesized a peptide made up of 7 amino acids. After cleaving the peptide with TFA, we tried to precipitate the peptide from cold ether. However, it seems like our peptide is somehow soluble in ether. Are there any other organic solvents to precipitate peptides?
Hello, could someone assist me in interpreting the results of the sequential Mann-Kendall Sneyer test? Indeed, according to Dufek (2008: Precipitation variability in São Paulo State, Brazil), "In the absence of any trend, the graphical representation of the direct series (u(t)) and the backward series (u'(t)) obtained with this method yields curves that overlap several times." In my case, I observe two to three overlaps, often with sequences that exhibit significant trends. Should I also conclude that there is an absence of trends in my dataset?
How can I train an ANN using current raster data (population, precipitation, DEM, land use) and use this model to predict future land use based on upcoming raster data (population, precipitation, temperature)?
I've been studying the relevant theory extensively recently, and I'd like to find a case study to see how it's practically implemented. Could you please guide me to where I can find similar case studies? I've noticed that many papers follow this approach, but I'm struggling to locate any code examples.
If there are no case studies available, I'd like to understand how to use raster data as inputs for an ANN and what preprocessing steps are needed, especially when dealing with multiple raster data inputs.
I have produced citric acid crosslinked samples of magnesium and sodium lignosulphonates and tried to precipitate my samples as they were water soluble during washing .I tried to preciptate with 0,1M , 1M and 2M HCl but none of it caused precipitation of my sample.The pH of the crosslinked sample was between 3-4.
Could anybody please suggest any other methods to precipitate the sample or a possible reason for no precipiation.
Thank you very much
I performed DLS on purified exosomes with an EXO SPIN kit (precipitation and size exclusion chromatography) the Z-average was too big and the result wasn’t good I should mention that to break up aggregations I do sonication before analysis. Does anyone have any idea? Could filtering through 0.2 µm be a solver?
Tell me, on which rim of the centrifuge (G) can the suspension of plant cells be precipitated without damaging the cells?
I have been purifying a His-tagged protein first using Ni-NTA chromatography and then Gel Filtration. After purifying using Ni-NTA, the protein seems to be precipitated after keeping the protein overnight on ice (or even for few hours). The protein was eluted using a gradient of buffer using 500 mM Imidazole (in a buffer of 20 mM Sodium phosphate, 500 mM NaCl, 10% Glycerol, 1 mM DTT). I tried to remove the precipitation by centrifuging but it seems majority of it seems to be completely precipitated (very less in soluble fraction).
Any ideas? Thank you
In the past I have conjugated an acid to polyethyleneimine with percentage conjugation of around 25%. I wanted to increase this percentage, and so I doubled the amount of acid, EDC and NHS before this solution was added to the polyethyleneimine. After allowing to react in methanol, with no solubility issues, after I precipitated the polymer as normal in diethyl ether, I have found it is now insoluble in water or methanol. However, there was no suggestion of the polymer "crashing out" of solution in methanol while the reaction was stirring. Why is the polymer precipitate suddenly insoluble when this has never been an issue previously? The acid I am using is a simple phenylboronic acid.
I test BOD of inlet sample of sewage water, in which there is no problem in inital DO but when i incubate it for 5 days, after incubation when i go for estimation of final DO, on addition of MnSo4 &Azide respectively the colour of bottle turns white insted of yellow & finally on addtion of H2So4 it totally yruns transparent. Whereas the other two samples of blank and outlet does not show such change.
I am working on #RNA SELEX. During the process of converting RNA to cDNA, I found precipitation in the RT product. Can anyone suggest to me how to get rid of this precipitation? i am guessing I am not converting all RNA to cDNA; this precipitation might be the secondary structure formation. How to minimize this precipitate formation?
I have precipitated out the protein using acetone from the alkaline-base buffer (NaOH + SDS+ EDTA + Beta Mercaptoethanol).
Desiccated Precipitates weigh more than the sample i.e for 2 grams of hair sample used, I am getting 2.6 grams of precipitates
Can one guide me on how can i separate my protein from the Desiccated Precipitates? Due to a limited budget, I can't use fancy techniques.
I am doing Trend analysis. When I was doing Homogeneity tests ( Pettitt, SNHT test, Buishand, von Neumann) on Precipitation and Temperature time series using XLSTAT, I found that a great number of my Temperature data are inhomogeneous. Can anybody tell me How can I make them homogeneous data?
I'm trying to reconstruct the time series of a weather station over the whole 1991-2020 period by using an external model as predictor.
I've successfully used ERA5-Land as predictor for temperature as the correlation with station data is quite high, however I'm struggling to do the same for precipitation.
What is the best alternative to reanalysis in this case? I was thinking about datasets of daily precipitation measured from satellite but the data seems to be quite coarse.
In my case I have the following requirements
- Temporal coverage from 1991-01-01 onwards (at least until 2020-12-31, but extension to present is quite important)
- Daily accumulated precipitation
- Grid spacing lower than 0.25 degrees
- Coverage of the Mediterranean area
You have any suggestions on which dataset I could use?
We have been trying to detect cytokines from equine synovial fluid using milliplex equine cytokine/chemokine magnetic bead panel. However it is rather hard and the values are always below detection. Is there anyway we can improve our sample? Can TCA acetone precipitation help concentrating the proteins and would the proteins still be detectable if we use this method?
Hello, I tried to prepare 10g/L MnCl2 solution but it got precipitated. What can be the possible reasons?
We cultured MSCs on calcium phosphate discs for 3 days and 7 days. We are seeing strange crystal-like precipitates or something of the sort (images attached). They are found wherever cells are found, or nearby cells, that are growing on the surface of the discs. We did EDS on these samples out of curiosity and the crystals appear to have a high concentration of NaCl, which indicates that they are salts.
I can't find any literature that shows this happening in their cell studies. Has anyone else seen this sort of thing happen in their cell cultures? I have no idea what could explain these results and I would appreciate some insights, or hypotheses, if any.
I purified one protein using 3 different columns. The last column I used is Butyl 650M hydrophobic interaction column and I eluted my target protein with 50% propylene glycol. I need to remove propylene glycol and concentrate my elution. I tried to remove it with acetone precipitation, and methanol chloroform precipitation. However, both of them resulted in a significant loss of my protein.
I wonder If I can use dialysis or not...due to its water-absorbing characteristic...
I do not want to add additional steps like gel filtration chromatography...
Does anyone have any technical suggestions and ideas?
I need to improve the solubility of Potassium Humates in hard water. Generally, potassium humates are soluble in hard water but within a few minutes, it has precipitated due to the complexation of humates with Ca & Mg ions. Can anyone help me to avoid this precipitation or sedimentation?
The Impact of Climate Change on Water Resources..... how do you measure precipitation threshold to be classified as a storm event in louisiana?
Hello, I am an undergrad trying to follow the methodology of the paper attached. I'm working with 50 mM phosphate buffer and 250 mM MgCl2 for hexokinase phosphorylation of CNF. I don't entirely understand why that concentration of buffer was used, and I keep getting Mg(OH)2 precipitates upon trying to get to pH 7.6. What could I be doing wrong?
Please somebody can share a script for ( to run on CDS toolbox editor https://cds.climate.copernicus.eu/toolbox-editor ) daily total precipitation data extraction on a point location for custom period (several years) ?
My polyurethane like polymer, when precipitated in ether gives a lower Mn while the same when precipitated in methanol gives a higher Mn. I have looked a lot in the literature to find some good explanation to it but seems to get nothing. Can someone please explain me.
I have downloaded two types of half-hourly and three-hourly satellite precipitation data for the study area from Gportal. Now I have a question about those data, please help in this regard.
GPM_3IMERGHH half-hourly NetCDF file
Question 1: Does this file cover the amount of precipitation from 23:45 UTC of the previous day to 00:15 UTC of the current day or it represents the period from 23:30 UTC of the previous day to 00:00 UTC of the current day?
GPM_3IMERGHH half-hourly NetCDF file
Question 2: Does this file cover the amount of precipitation from 10:00 UTC of the current day to 10:30 UTC of the current day or it represents the period from 10:15 UTC of the current day to 10:45 UTC of the current day?
TRMM_3B42RT three-hourly NetCDF file
Question 3: Does this file cover the amount of precipitation from 22:30 UTC of the previous day to 01:30 UTC of the current day or it represents the period from 21:00 UTC of the previous day to 00:00 UTC of the current day?
GSMAP 1-hourly HDF file
Question 4: Does this file cover the amount of precipitation from 17:00 UTC of the current day to 18:00 UTC of the current day or it represents the period from 17:30 UTC of the current day to 18:30 UTC of the current day?
I used linalool standard for estimating total terpenoid content for my plant sample, different linalool concentration has been taken and finally the supernatant has been discarded, the red precipitate ring is treated with solvent. while discarding the supernatant either micro ml of precipitate been drawn or left with micro ml of supernatant, due to this i am unable to draw a standard curve and the values are non-linear . kindly help me out to find a better way for doing this experiment
- Numerous studies have suggested that carbonation and serpentinization of silicate minerals are controlled by an interface-coupled dissolution-precipitation mechanism (e.g., Putnis, 2002, 2009, 2014; Plümper et al., 2012; Altree-Williams et al., 2015).
- Moreover, this mechanism can lead to the pseudomorphic (isovolumetric) replacement of the parent phase by the product phase, assuming that the dissolution of the parent phase and the precipitation of the product are coupled in both space and time (Brugger et al., 2010; Putnis, 2009; Qian et al., 2010; Altree-Williams et al., 2015).
- However, I'm curious about the question that "could the interface-coupled dissolution-precipitation mechanism necessarily also not lead to pseudomorphic texture generation?".
So far I have found partial data, not a global coverage.
Data by station or simply a raster image would be great, as I need to calculate the average wind speed and precipitation by subnational region (for which I have a shapefile with the administrative boundaries).
Hi ResearchGate community,
I am interested in using chemical flocculation to concentrate water samples for eDNA analysis. This is basically to avoid having to filter water.
I have come across interesting papers on this subject, however, people use chemical flocculation for the precipitation of entire cells (bacterial communities). I am wondering if this method can also work when we are dealing with environmental samples (cells + mitochondria + free floating extracellular DNA + mucous + fecal matter, etc). I would appreciate if anyone with experience with this could comment. I am interested in knowing what is the % recovery of this method.
I'm trying to conjugate azide-MMAE compound to a protein. The azide-containg group is soluble in DMSO. The problem is when i combine all the ingridients for the reaction i get precipitation and only the protein remains (checked in MS analysis). My theory is that the amount of DMSO is so little in the total amount of the reaction that the organic compound is not soluble anymore. How do i prevent the precipitation of azide-MMAE, while also not denaturing the protein?
My reaction is as follows (for 1 ml, 37C, 550 rpm, 2hr):
50 ul of 50mM THPTA
25 ul of 20mM CuSO4
160 ul of 31.195uM protein
20 ul of 5mM azide-MMAE (stock is 50mM and diluted with PBS)
50 ul of 100mM ascorbic acid
and PBS to 1 ml
I would appreciate any assistance on this matter.
I have tried to modify gelatin with methacrylic anhydride (MA). However, when MA was added into gelatin PBS solution, it will form milky emulsion and a kind of precipitation. after dialysis, the precipitation can be reduced in some extent, but still exists.
can I ask whether this is a normal procedure or what should I do to avoid the precipitation?
Hi, I have monthly precipitation and monthly temperature (not classified as minimum and maximum). How can I calculate SPEI index using Rstudio? I have also additional inputs like year, months and latitude of the location where I am conducting research.
I recently started to use peptides for cellular studies. Unfortunately, when I was designing the peptides I did not have a FITC tag to them (the peptide was synthesized by an external company). The peptides still have an -NH2 terminal that I can react with FITC-NHS pretty easily. But due to the small size I would not be able to isolate the peptide from unreacted/hydrolyzed FITC-NHS by MW cutoff as I would for proteins.
The peptides are not very cheap so I would seek alternatives than purchasing more tagged peptides. While I know I could purify it by HPLC followed by concentration / lyophilization, it's adding a lot of procedures to the pipeline and I'm considering if there could be alternatives. And so, I'm wondering if peptides could be precipitated by TCA/acetone precipitation similar to proteins?
While I believe the precipitation is dependent on the peptide structure, I used one of our peptides and tried it out - the precipitation worked (I saw visual white fluffs) and the peptide absorbance curve showed peaks at 214/280. The curve looked identical to the peptide solution (unprecipitated) but with a lower absorbance unit (22 AU compared to 5 AU post-precipitation).
My question is, is this way of isolating peptides legit? And if I used FITC-NHS, would FITC also be precipitated by any chance? Will the peptide lose stability / increase cytotoxicity during TCA exposure? I am not using the peptide for functional studies, just trying to visualize cellular internalization.
- If this way makes no sense I will refer to other methods. Thanks for any suggestions.
I would like to prepare a calcium carboxylate. The procedure is overbasing the carboxylic acid with excessive Ca(OH)2 than bubbling CO2 through it to precipitate CaCO3. Can I just throw some pieces of dry ice into the mixture? Gas cylinder is hard to handle.
i would like to download Daily temperature data and daily precipitation data ERA5 reanalysis data, Anyone with a simple python code to help me kindly?
An additional column comes with the data as follows:
- a number code of 5, 6, 7, or 8 for wind speed
- a letter code of F, E, I for precipitations (rain)
Many thanks in advance for letting me know what it means!
Cesar on behalf of the Magnetics project team
I'm trying to assess protein interaction in a chelating sepharose column with nickel. When I added the first protein and collected the flow-through was everything okay. When I added the second protein, it almost didn't get through the column. Looking at it, it seems that my first protein is indeed binding to nickel but it clogs up the column since we can see the red colour only in the upper part of the column. Using 10 mM, 50 mM and 100 mM of imidazole I have a flow of almost 1 mL/h. When I add 500 mM of imidazole the flow gets faster and all protein comes out. This protein has a propensity to precipitate. I'm using 20 mM Tris 500 mM NaCl 10% glycerol as buffer. I'm wondering why this is happening and what should I do? Add a reducing agent? Is possible that my protein is forming some sort of complex with nickel?? Help
I want to try different global and temperature models and their data that want time, longitude, latitude, and height as inputs. I already tried different models for zenith tropospheric delay and precipitable water vapor, such as the Gtrop, Gpt3, Gpt2w, and Hgpt2 models. But I want something that looks like these models, which give me pressure and temperature in output.
Is there another model other than the ones mentioned that I can use?
It's important to me that you try more models.
Thanks a lot.
Now I want to access the two future simulations of temperature and precipitation in the CMIP6 dataset (in ssp126, ssp245, ssp370, ssp585 senario). It is only necessary to obtain the data for the Chinese region. Finally it will be carried out to calculate the annual average of rainfall and temperature for each province according to the regional boundaries of the Chinese provinces. How do I implement it?
I'm trying to start modeling asphaltene precipitation. Since I read studies related to asphaltene precipitation, I have found that modeling with PC-SAFT equation of state is most appropriate.
However, I don't have any software or MATLAB code that can model VLE and LLE for the system with multicomponents.
Would you please recommend me some free software or code for PC-SAFT EOS?
Why do western slopes of Western Ghats receive orographic rainfall and precipitation different from other parts of the water cycle?
Why does orographic type of rainfall occur in Indian plains and peninsular region and difference between precipitation and rainfall?
I have been following the paper https://doi.org/10.1039/C7NR06732A to synthesize them, but I could not synthesize microgels with a Polydispersity Index of less than 0.01. My microgels have a Polydispersity Index of 0.05 and an average hydrodynamic diameter of 750 nm, and zeta potential is also less, -2 mV. I first dissolved 0.25 g NIPAM and 0.009 g BIS in 20 ml of DI water under continuous stirring at 150 rpm in a nitrogen gas atmosphere at 70-degree temperature. After 30 minutes, I added 0.02 g KPS dissolved in 1 ml of DI water to the solution and let the reaction continue for 6 hours. Then it was cooled to room temperature and continuously stirred for 12 hours. Finally, I found that some portions of the polymer precipitated and some amounts dispersed in DI water.
While concentrating my GST-tagged protein in a Merck 10kDa cutoff Centricon , the protein appears to be aggregating/precipitating. As is understandable when there is turbidity/whitish appearance in the column . Just simple mixing is just not helping.There is huge protein loss. The buffer I am using for buffer exchange has 50mM Tris-Cl (ph8) and 50mM NaCl. And I have kept the NaCl conc in lysis and washing buffer(for GST purification) at 200mM.
Am I doing the process wrong?
Any suggestions would be appreciated!
Yesterday, I prepared the minimum medium Yesterday, I prepared the minimum liquid medium for the screening of bacteria that have the ability to degrade naphthol and use it as a single carbon source which is composed of:
1,0 g K2HPO4-2H2O
1,0 g KH2PO4
5 g NaCl
0,3 g (NH4)2SO4
0,3 g MgSO4-7H2O
20 mg CaCl2
5,0 g ZnSO4
2,3 g FeCl3
5,0 g MnSO4
1,0 g (NH4)6Mo7O24
This is the composition that suits my bacteria, I was inspired by this article: https://sci-hub.se/10.1016/j.jhazmat.2010.06.101
Biodegradation of naphthalene by strain Bacillus fusiformis (BFN)
but the problem is that after autoclaving, there was the precipitation of the components at the bottom of the bottle .
can I add before autoclaving a solution of cacl2 so that there is no precipitation? and how much can I add of this solution in 1 liter of minimum media ?
Please give me all the tips I can do or avoid to succeed in this medium
Than you .
For my research purpose i have prepared polyquaternium 7 with 41 - 45 % solids and viscosity in the range of 2000 - 45000 using 70 % acrylamide and 30 mol % DADMAC
polymer solution itself is clear and transparent but when i mixed it with CAPB and SLES solution it precipitated and gives haziness to the solution
I am trying to purify a heterologous protein with His tag in yeast but I am facing issues with binding my protein to Ni-NTA beads. Please suggest some methods to purify my protein of interest.
These are the conditions I have followed
My protein of interest was precipitated from Pichia X-33 cells culture supernatant (400 ml) on day 4 using 60% of ammonium sulphate. The precipitated protein pellet was dissolved in 6 ml of buffer (Tris-20 mM, NaCl-500 mM, pH-8). 6ml of dissolved protein was dialyzed in 3 cycles of dialysis (Buffer: Tris-20 mM, NaCl-500 mM, pH-8). Dialyzed protein was purified using Ni-NTA agarose beads. My protein PI:6. I have used the same dialysis buffer with 20 mM and 40 mM imidazole for washing.100 and 300 mM imidazole for elution. My protein is not binding to Ni-NTA agarose beads. I have tried at pH:7.4 also. In all the cases it's in flowthrough.
I have attached the gel image also.
In the adsorption removal of heavy metals, we typically focus on kinetics, thermodynamics, and isotherm. What about the studies that are commonly used in the precipitation technique?
I found a discrepancy in ERA5-Land precipitation product. The monthly data is in theory the daily mean precipitation in meters per day. The problem is that when computing this from the hourly data the result is not the same value. I computed this for several months and grid-points, and I found in each case a discrepancy. Does anybody know why this discrepancy exists? Is there a problem/issue with the ERA5-Land product? If that is the case, which product is "correct"?
When I found this, looked for it on google and I only found this post: https://stackoverflow.com/questions/75698506/discrepancy-in-data-on-total-precipitation-from-era5-monthly-vs-daily-data
There another person got the same discrepancy, then in the comments, another researcher got also the mismatch in the precipitation values.
I am trying to do bias correction for rainfall data using the ‘qmap’ package in R.
My daily observed data is collected from 1981 to 2014 at the point (station) scale. To downscale the future data, I extracted the variable for corresponding locations from GCMs, including historical and future period (1981-2100).
The observed and GCMs data are detected the relationship and estimate the parameters of downscaling future data. But when I do that using qmap package, the results are poor. The output data is aggregated to monthly scale, and evaluated the performance of different GCMs with root mean squared error (RMSE) and correlation coefficient (r). From the results, I found that the bias correction even decreased the r. Additionally, I also provide the boxplot for month and annual precipitation. The above results are based on the fitQmapRQUANT method in the ‘qmap’ package. I also tried to other methods (fitQmapDIST, fitQmapPTF, fitQmapQUANT, and fitQmapSSPLIN), however, the results are still poor.
Does anyone get such results or I am doing it in the wrong way? How can I apply "qmap" to downscale daily precipitation data with my observed data?
Thanks in advance
I am trying to grow Pichia pastoris X33 in the basal salts medium provided by Invitrogen. However, on adjusting the pH to ~ 4.50-5.00 using ammonium hydroxide and addition of PTM trace salts, a heavy precipitation in the media is observed. Why is this so and how can this be avoided?
When I try to prepare 1M MgCl2 solution using anhydrous magnesium chloride (AR), the solution will exotherm (obviously) then produce some white precipitates (supposedly Mg(OH)2), followed by some black precipitates which cannot be dissolved after adding HCl. I would like to know what these black precipitates are, could they be MgCO3, or something else? Also, the water used for dissolution is the Ultrapure water.
Thank you for your answer :-D
are there ways to recover back the purified protein that was precipitated because of too much centrifugation? Since I forgot to shake my protein sample which was in a concentrator during the pause of centrifugation, it eventually precipitated and the protein concentration was very low. This protein was already purified by several columns.
i am try to synthesize the schiff base compound from aniline derivatives and vanillin use ethanol as a solvent and i am try first without catalyst no precipitate form then i use glacial acetic acid also no precipitate form but when i use sodium hydroxide as catalyst the yellow -white precipitate form with deffer melting point than reactant but when i mentoring by TLC the spot appear in vanillin and the elemental analysis of C,H,N give result deffer from my product can you help me ?
I am looking for observed rainfall data in different regions, such as the USA or Europe or Africa or China.
I will be thankful for any kind of help.
I've extracted PHA in chloroform using soxchlet extraction method at 65 degree celsius and tried precipitating the dissoloved polymer in cold methanol (70%), but could'nt see any precipitation. I've tried this method many times but not able to see the polymer. Is there a problem with my extraction method or the produced polymer is so low in concentration that I'm not able to get the precipitation.
i am starting my master thesis And I am doing polymer synthesis following by precipitation method (dissolution in solvent, non solvent precipitation, centrifugation) repeated 2-3 times. I have some impurities in my NMR analysis.
So I want to know if precipitation method in cold ethyl ether is enough to purify a polymer chain ? if yes, it the best procedure to do a good purification through This method?
Example: addition drop by drop is important ? Stirring fast also ?
Is it better than soxhlet extraction ?
Another suestion regarding the purity of final product. Is GPC can confirm the formation of product ? How can I confirm clearly that the reaction work and the product is formed (in complement with NMR) ?
Hello Dear scientific community, I want to apply AI methods for rainfall-runoff prediction. However, I am still stuck in the database construction for model input. I have selected the precipitation and temperature factors, I have the data of vegetation cover and soil type but don't know how to use it as input.
- Is it possible to enter different inputs with different column numbers, for example, is it possible to integrate the LULC and soil type with precipitation and temperature.....?
- If someone is familiar with this subject, Please advise me
- I am trying to increase the media’s calcium content to provoke microvesicle release but everytime I try to add it into the media it precipitates out of solution. I’ve tried using stock solutions and adding them slowly in to the media (serum free) and all I get is precipitation. Any help would be greatly appreciated.