Precipitation - Science method

I have searched the web for some possible solutions and advice for your problem. Here are some of the results that I found:

Based on these results, it seems that CTAB buffer with PVP is a common solution for extracting DNA from plant materials that have high amounts of pigments and other contaminants that affect DNA quality and quantity. You may want to try this method or modify it according to your needs and see if it works better than the protocol you attached.

Here are the references

: [A simple and efficient method for DNA extraction from grapevine cultivars, Vitis species and Ampelopsis] by A. Lodhi, G. N. Ye, N. F. Weeden, and B. I. Reisch, Plant Molecular Biology Reporter, vol. 12, no. 1, pp. 6-13, 1994.

: [A rapid and efficient method for isolating high quality DNA from leaves of carnivorous plants from the Drosera genus] by M. Tretyakova, A. Romanovskaya, A. Shmakov, and V. Sizykh, BMC Research Notes, vol. 7, no. 1, 926, 2014.

: [A simple method for isolation of genomic DNA from fresh and dry leaves of Terminalia arjuna (Roxb.) Wight & Arn., a medicinal plant] by S. Kaur, R. Ahuja, S. Kumar, R. Chaudhury, and A. Srivastava, Molecular Biotechnology, vol. 40, no. 2, pp. 167-172, 2008.

Annulohypoxylon sp. strain MUS1, an endophytic fungus isolate...

https://pubmed.ncbi.nlm.nih.gov/

https://scholar.google.com/

Good luck

Dr Raffaele Salerno thank you for your contribution to the discussion

Surfactants do not "dissolve" - they emulsify and disperse

Before the earthquake in Algeria (map), during the stretching of the earth's crust, convective clouds formed in the desert (water evaporated from the surface of the earth???). https://www.sat24.com/history.aspx Where did the water come from there that day?

Even Xu Thank u. But, I'm working with chemical polymers.

I don't think 5000 MW is a polymer, may be it is a true oligomer. You should search and find kinetics studies on MW evolution with respect to polymerization time. These are old studies. My Regards

This article might be helpful for you:

You could lyophilize the mixed solution TFA-ether that contains the peptide.

Ma'Mon Abu Hammad Could you advise me on some documentation about this test?

Xuyang Bai

Hi,

utilizing an Artificial Neural Network (ANN) to predict land use based on raster data is a potent application of machine learning in geospatial analysis. This approach involves training a model on historical raster data, such as population, precipitation, Digital Elevation Model (DEM), and existing land use, and then leveraging this trained model to forecast future land use patterns using forthcoming raster data containing parameters like population, precipitation, and temperature.

To practically implement this approach, you can follow these steps:

As for case studies and code examples, you can explore academic journals, conferences, and online repositories like GitHub. Many researchers have indeed explored this approach, but the specific code examples might not be readily available due to variations in dataset availability and implementation choices. Look for papers that discuss their methodology in detail; they often provide insights into the data preprocessing, model architecture, and evaluation techniques used.

Anumol James Addition of alcohol?

Hi,

Exosome size measurements through DLS tend to be variable , thus should be repeated several times in single as well as multiple different preparations, in order to reach a cumulative particle size range . Please pay attention towards QC report at the end of each measurement ('Good' report means acceptable results). Further you may need to modify the default DLS protocol method in order to fit EV measurements.

Filtering through 0.2um could be helpful but sonication will break up the EV particles giving incorrect sizes.

NTA is a better method to quantify EV size and concentration.

Regards

Neha

Dear Dr Sallam

The formation of a blue-black precipitate when iron(III) is mixed with tannic acid can be attributed to the formation of a complex between the two substances. Iron(III) ions (Fe³⁺) have the ability to form coordination complexes with various ligands, and tannic acid is a polyphenolic compound with multiple functional groups that can serve as ligands. The blue-black color of the precipitate suggests the presence of a specific complex that exhibits this color.

In a low pH environment (pH=2, as you mentioned), tannic acid molecules are likely to be partially or fully protonated, resulting in a higher concentration of positively charged species. These positively charged tannic acid species can interact with the negatively charged iron(III) ions, leading to the formation of coordination complexes.

The exact structure and composition of the complex formed between iron(III) and tannic acid can vary depending on factors such as the molar ratio of the reactants, the specific functional groups on the tannic acid molecules, and the conditions under which the reaction takes place. One possible complex that could contribute to the blue-black color is the iron(III)-tannic acid complex called "iron(III)-tannate" or "ferric tannate."

The blue-black color might arise from the interaction of the complex's structure with light, leading to absorption and reflection of certain wavelengths that result in this particular color perception. The complexity of the formed complex, along with its arrangement and electronic transitions, can contribute to the observed color.

If you're working with these complexes and observing the formation of a blue-black precipitate, it's likely that you are indeed forming a specific iron(III)-tannic acid complex. Characterizing this complex through techniques like spectroscopy (UV-Vis, IR, etc.) and elemental analysis could provide more insight into its structure and properties.

Dear Ekaterina Anatolyevna Lapchenko,

Unfortunately, I do not have any experience or knowledge about this subject.

Best regards.

DTT reduces the Ni-NTA to Nickel solid making a brown precipitate. Did you observe that? Phosphate salts are have low solubility especially at cold temperatures in the cold room so if the sodium phosphate is precipitating, your protein is dissolved in it so it is precipitating with the sodium phosphate. Tris and Hepes are more soluble buffers and are better options and I think Tris is cheaper.

Your protein is least soluble when the pH of the solution equals the isoelectric point of your protein (pI) because the protein is uncharged at the isoelectric point. But for binding to Ni-NTA, the pH of the buffer has to be pH >= 7.8 because at lower pH, the polystidine tag is protonated and so it can't bind to Ni-NTA.

Plug your protein sequence into ProtParam to estimate the isoelectric point:

Try to avoid having the pH of your buffer being near the isoelectric point.

Yuri Mirgorod thanksnfor your help. Yes we found by lowering the pH of the solution we were able to dissolve the precipitate. Also found a paper regarding if PEI amines are unconjugated the amines will intertwine and need to be charged to electrostatically repel and allow dissolution.

Dear Parvaiz,

Here is some additional information that may also be of interest. The brown precipitate is MnO(OH)₂, containing Mn(IV), which forms when dissolved oxygen (DO) oxidizes the Mn(II) added in the form Mn(OH)₂. If there is no DO in the sample after incubation, then the brown color will not form. Were the inlet samples sufficiently diluted so that some DO remained after the 5-day incubation? A dilution factor of 20-60 or more may be needed, depending on the sewage strength.

By the way, the azide is used to prevent interference caused by any nitrite present. If the lab sink has a U-trap made of lead, the unreacted azide going down the drain when you pour out the BOD bottles can react with the lead to form explosive lead azide (PbN6), posing a real risk to any plumber or other person who services or otherwise contacts the trap.

Best of luck with your work!

- Peter

No, ethanol would not do anything of note, and the probability of 'leftover ethanol' being present should be zero.

Also, you state that your concentration is "very high, 3750ug" but this is an amount, not a concentration. 3750ug per what?

It would probably help, to be honest, if you provided a lot more detail about what you're doing at each step, and why you're doing it that way.

You may also test meoh-chlorofom Folch precipitation method to get proteome as an interphase pellet...Alternatively, Trizol extraction could be beneficial...Trial and error-based approaches to get the highest recovery...

Use normalization techniques such as min-max normalization or z-score normalization. Another method is to use feature scaling techniques such as standardization or normalization.

Hello Guido,

try The Satellite Precipitation - CMORPH Climate Data Record (CDR) consists of satellite precipitation estimates that have been bias corrected and reprocessed using the the Climate Prediction Center (CPC) Morphing Technique (MORPH) to form a global, high resolution precipitation analysis. Data is reprocessed on a global grid with 8km-by-8km spatial resolution. Temporal resolution is 30 minutes over a 20 year period of record (January 1998–present). The output precipitation fields are produced on three different time-space resolutions to accommodate a variety of user requirements.

Hi Burcu Gür

With the Target 96 Immunopanels (INF, IO, IR) or the T48 cytokine panel you should be able to cover most (if not all) of your targets of interest.

Shoot me an email and I connect you to the closest sales person, if you are inetrested.

All the best,

Michael

One possibility is that it is MgCO3 that is being precipitated with the carbonate being supplied from CO2 in the air. Are you using distilled or tap water?

Hi Genesis Marrero

Interesting observation! Based on your description, it seems like the crystals could indeed be salt precipitates. There could be several reasons for this, here are a few possible explanations. Media evaporation: If your cultures are not fully sealed or the incubator is not properly humidified, evaporation could cause the salts in the culture medium to become more concentrated over time. This might lead to precipitation, especially near cells which could act as nucleation points for crystal formation. Interaction with the disc material: Calcium phosphate could be reacting with components of the culture medium, leading to formation of insoluble salts. I hope these ideas help you in understanding and investigating this phenomenon further!

Ultrafiltration...

I suggest doing the dilution little by little under agitation and heating and doing a treatment to reduce the hard water salts. You could decalcify using ion exchange resins to capture calcium and magnesium from hard water.

Let me answer your first Q about "The impact of climate change on water resources" - Climate change messing with our water resources is a big worry. it messes up how rain falls, makes crazy weather happen more often, and messes with how water moves around. need to understand how storms affect water supply, floods, and nature. It's all about dealing with climate change and how it affects our precious water!

In Malaysia, how we define a storm event differs depending on where you are and who's studying it. But generally, we do a few things to figure it out:

Step 1: collect rainfall data from various weather stations nationwide. measure how much rain falls and for how long, usually every hour or day.

Step 2: look at all that rainfall data to spot any cool patterns or trends. watch for crazy heavy rain that goes on for a long time – that's when it might be a storm event!

Step 3: Using historical data and climate patterns, set a certain level of rain that makes something a storm event in that specific area. this can vary depending on the local climate and the place's geography.

Step 4: Storm events can be classified in different ways – like how much rain falls in an hour or the total rainfall over a specific time period. It helps to understand what's considered a storm.

Step 5: Check older data to find past storm events. This helps to see how often and intense storms were in the past and if anything changes.

Step 6: with climate change messing things up, we must look at historical data differently and consider how storms might change over time. Use fancy climate models to predict future rainfall trends and how storms could evolve in the future.

Step 7: keep a close watch on rainfall data all the time and update our storm event rules regularly. This helps us adapt to any changes caused by climate change messing with our rain patterns.

Hope this could help! If we stay curious and keep studying our weather, we can better understand how to deal with storms and climate change's impact on our precious water resources.

Often it is magnesium phosphate that is the precipitate. Usually you formulate your phosphate buffer to be the right pH based on the mix of mono- and di-basic phosphate that you add and then autoclave. You then add the magnesium when cold from a separate stock solution.

Dear Awad, to calculate seasonal precipitation Anomaly for 30 years using CDO you can do this as follows:

cdo ymonmean infile.nc outfile_climatology.nc #### The command "cdo ymonmean" is used to calculate the monthly mean of a dataset

and then

cdo ymonsub infile.nc outfile_climatology.nc outfile_anomalies.nc ####cdo ymonsub is used to calculate monthly anomalies from monthly climatologies

I hope this can help you

Guyen Battuvshin, many thanks for your answer! I am just worring about "climate.daily_mean()" function - it is decleared to calculate only average value for each day, so here I see an issue.... or this function work in another way with precipitation data... Do you check results of this output?

Dear all, in the precipitation process one should consider the binary state of solvent/nonsolvent mixture. In which solvent PU is being dissolved ? My Regards

In addition to the excellent approach mentioned by Enda William O'Brien, which involves statistical adjustments based on available data, it is also possible to adopt approaches that take into account the scarcity of available data. One such approach is spatial interpolation, which is highly useful for estimating precipitation values in locations with insufficient data. By utilizing information from nearby stations with more complete records, it is possible to fill in the data gaps of recently installed stations.

Furthermore, historical data analysis from nearby stations with longer precipitation records can be employed to infer precipitation patterns in the area and fill in the data gaps of the new station, allowing for a better understanding of the climatic context in which the Standardized Precipitation Index (SPI) is being calculated.

Thanks to everyone, I got the necessary response from the support of the above products.

Thank u for ur response Sir . But my work is to just estimate the total count of terpenoid using basic standard protocol. Now I switched to ursolic acid with some modified procedure for this estimation.

The interface-coupled dissolution-precipitation mechanism, while often resulting in pseudomorphic replacement of the parent phase by the product phase, does not necessarily always lead to pseudomorphic texture generation.

This is because the generation of pseudomorphic textures depends on several conditions being met, including isovolumetric replacement, conservation of original grain boundaries, and retention of the parent phase's shape and size. These conditions may not always be met in all dissolution-precipitation processes.

Additionally, the generation of pseudomorphic textures can be influenced by a range of factors, such as the rate of reaction, the nature of the parent and product phases, the solution chemistry, and physical conditions like temperature and pressure.

Therefore, while the interface-coupled dissolution-precipitation mechanism often leads to a pseudomorphic replacement, it does not necessarily always lead to the generation of pseudomorphic textures. There can be cases where this mechanism could result in non-pseudomorphic replacement, particularly if conditions are not conducive to maintaining the original form of the parent phase during the replacement process.

merci Mohamed !

Nucleic acids, lipid, and colloidal particulate material can be selectively flocculated from a yeast cell homogenate by the cationic polymer polyethyleneimine (PEI). Flocculation can occur from a crude homogenate, a homogenate clarified centrifugally, or by the prior use of sodium tetraborate (borax).

One strategy may be putting a hydrophilic spacer that increases the azide-MMAE compound's solubility in aqueous media for successful click chemistry. There are many options...

Refolding after bioconjugation may be the second strategy...

Third, non-ionic, non-denaturing mild detergent may also be helpful to increase solubility for MMAE. But I am not sure if this alters the conjugation...

Just a follow up on this question. I've had the same issue now and wanted to ask: Did it affect down-stream applications? Did you remove the precipitate by centrifugation? Or did you simply start over?

Thank you very much, appreciated!

Jos Feys

Success depends a little on the hydrophobicity of your peptide.

I'd try dry Et2O first, esp. if the volume of reaction is small, so all water gets can dissolve in the ether. If it should not work, remove the ether and try isopropanol or ethanol: Begin with small amounts, cool and centrifuge, then increase the alcohol concentration until your labeled peptide precipitates. Fluorescein will precipitate sooner or later, too (pH dependent).

If you try Adam's suggestion, keep all fractions until you know that the operation was successful. For concentrating the peptide, use precipitation as above. There is a high chance that the fluorescein gets trapped on the column and is moving *very* slowly (which is in your favor).

Could you not put he solid CO2 into a container and bubble the gas through the calcium hydroxide solution?

Throwing the solid CO2 into the solution may simply freeze it

Well, first, you'll need to register for an account on the Copernicus Climate Data Store (CDS) website: https://cds.climate.copernicus.eu/

After registering, follow the instructions to install the CDS API key on your computer: https://cds.climate.copernicus.eu/api-how-to

Next, install the CDS API client for Python by running the following command in your terminal or command prompt:

pip install cdsapi

Now, you can use the following Python script to download daily temperature and precipitation data. Make sure to replace the start_date, end_date, and output_file variables with your desired values.

import cdsapi

start_date = "2021-01-01"

end_date = "2021-01-31"

output_file = "era5_daily_temperature_precipitation.nc"

c = cdsapi.Client()

c.retrieve(

"reanalysis-era5-single-levels",

{

"product_type": "reanalysis",

"variable": ["2m_temperature", "total_precipitation"],

"year": [start_date[:4], end_date[:4]],

"month": [start_date[5:7], end_date[5:7]],

"day": ["01", "02", "03", "04", "05", "06", "07", "08", "09", "10", "11", "12", "13", "14", "15", "16", "17", "18", "19", "20", "21", "22", "23", "24", "25", "26", "27", "28", "29", "30", "31"],

"time": ["00:00"],

"format": "netcdf",

},

output_file,

)

This script will download daily temperature (2m_temperature) and precipitation (total_precipitation) data in NetCDF format for the specified date range. You can then use libraries like xarray or netCDF4 to read and analyze the data in Python.

Keep in mind that downloading large datasets may take some time, so be patient while the script runs. If you need data for a longer period or at a higher temporal resolution, you can adjust the parameters accordingly.

Thank you Geoffrey, it is much appreciated! césar

Dear Beatriz Moniz

You can try using batch method instead of column purification. Briefly, you take Ni-NTA-sepharose and mix it with your protein in a probe, incubate, and then do washing and elution by exchanging the buffer above the resin. It requires more effort than using column, but may work in your case.

Regards

Tomasz

Greetings... Modern satellite visuals may help you with that if you can obtain them and analyze their climate data according to the climate bands.. Good luck.

If you can understand Chinese, you can read one of my blogs: https://zhuanlan.zhihu.com/p/424218019. Simply, it is actually using CDO to cut .nc file by .shp files.

You are looking for a graphical user interface? Unfortunately most implementations expect the user to use them from code.

Western Ghats receive more rainfall than the Eastern Ghats because (i) Western Ghats receive rainfall from the Arabian Sea monsoon winds. As these winds blow over warm oceans, they bring abundant moisture. (ii) The Ghats do not allow the winds to cross over without shedding their moisture on the Western slopes. The Western Ghats receive rainfall through Mountain type of precipitation. The winds from the Arabian Sea climb the slopes of the Western Ghats from 900-1200 m. Soon, they become cool, and as a result, the windward side of the Western Ghats receives very heavy rainfall ranging between 250 cm and 400 cm. Due to orographic rainfall, the western side of the Western Ghats receives heavy rainfall, more than 250cm rainfall per year. The Western Ghats block rain-bearing winds which cause rainfall on the western slopes. Whereas South-west monsoon moves parallel to the Eastern Ghats, which cause less rainfall because in the Eastern Ghats unable to block moisture-laden winds. Winds from the Arabian Sea ascend from 900 to 1200 m up the slopes of the Western Ghats. They soon become cool and as a result, very heavy rainfall ranging from 250 cm to 400 cm occurs on the windward side of the Western Ghats. These winds descend and get heated up after crossing the Western Ghats. The high montage forest ecosystems influence the Indian monsoon weather pattern. The Ghats act as a key barrier, intercepting the rain-laden monsoon winds that sweep in from the south-west during late summer. In orographic rainfall, the windward slope of the mountain receives maximum rain and the leeward slope remains generally drier and is known as the rain shadow area.

Orographic rainfall happens in tall mountains as the mountains act as a barrier for the clouds to travel from one place to other. Masses of moist air rise along on one side of the mountain, get cooled down due to condensation and form clouds.Winds coming from lakes or seas are moisture-laden. They are obstructed by the high mountain ranges coming in their way. They start going upwards along the slope of the mountains, the temperature of these winds drop and condensation occurs and rainfall takes place. The warm and moist air from the Arabian Sea is blocked by the Western Ghats and gets lifted over mountain ranges. As the air rises and cools, orographic clouds are formed resulting in precipitation and dry winds to blow over Peninsular India. Orographic rainfall happens in tall mountains as the mountains act as a barrier for the clouds to travel from one place to other. Masses of moist air rise along on one side of the mountain, get cooled down due to condensation and form clouds.Orographic rainfall is precipitation produced when the mountains of uplands act as barriers to airflow, forcing the air to rise and the moist air moving upslope coo down by producing clouds and precipitation. Orographic rainfall occurs in most of the world: Orographic rainfall occurs because of the obstruction of moisture laden clouds by the mountains and areas of high altitudes. These clouds are generally blown by the winds.Orographic rainfall occurs in most of the world: Orographic rainfall occurs because of the obstruction of moisture laden clouds by the mountains and areas of high altitudes. These clouds are generally blown by the winds.The difference between Rain and Precipitation is rain falls as water droplets, whereas precipitation can fall as snow, water, etc. Precipitation can take the form of liquid and frozen water or ice, whereas rain only happens when the precipitation is in the form of water.

Practice and luck.

The authors may have made ten different batches with only one having a PDI less than 0.01.

Years ago, the PhD group I was in had many projects concerned with making microgels. Most people struggled to get good PDI values at first. It came with practice.

I am no expert in this apporach. But how do you do the elution? Do you cut off the GST tag?

Dear Manel Moumene,

Try to prepare the medium by fractioning the solutions, one way in this particular case would be to prepare four solutions:

1. Phosphate salts (adjust the pH of this solution),

2. NaCl, Mg, Ca and sulfate ammonium,

3. Zn, Fe, Mn and Mo

4. carbon source solution.

Sterilize separately and collect them all at room temperature. Storing the reconstituted medium in the refrigerator can generate precipitation, so I do not recommend preparing large volumes.

Good luck

first，you have measure the rain precipitation and the runoff or seeps into the groundwater, and then you can model the ralation between them.

What is your washing media? Water? Try using some organic solvent like alcohol. your unreacted reactant may be soluble in that. Do check if your ppt is also soluble or not?

Also after drying do check the phase purity by XRD or any other analytical method. Hope it works..

Dear friend Tushar Deore

In your case, the addition of polyquaternium-7 can cause haze or precipitation in the formulation.

There are several possible reasons why polyquaternium-7 may be causing haze or precipitation in your SLES-based formulation:

To address the issue of haze or precipitation in your formulation, you may want to consider adjusting the pH of your formulation, reducing the concentration of polyquaternium-7, or using a different polymer that is more compatible with your surfactant system. You may also want to consult with a formulating expert to help identify the cause of the issue and develop a solution.

You need to reduce the salt concentration.. 500 mM is very high.

In the precipitation technique for removing heavy metals, some of the commonly studied aspects include:

Overall, the optimization of these parameters can improve the efficiency of the precipitation technique for the removal of heavy metals.

who can support me on the revised R factor estimation in the RUSLE

To download Global Precipitation Measurement (GPM) data in R, you can use the R package rGPM. Here are the steps to follow:

Install the rGPM package by running the following code in R:

install.packages("rGPM")

Load the rGPM package by running:

library(rGPM)

Download the GPM data using the downloadGPM() function. This function takes several parameters, including the date range and geographic coordinates of the area you want to download. For example, to download GPM data for the month of January 2022 for the area between 30 and 35 degrees north latitude and 80 and 85 degrees east longitude, you can run the following code:

downloadGPM(start_time = "2022-01-01", end_time = "2022-01-31",

bbox = c(30, 80, 35, 85), outdir = "/path/to/output/directory")

This will download the GPM data for the specified time period and location and save it to the specified output directory.

Note: You will need to sign up for a NASA Earthdata account and obtain an API key to use the rGPM package. You can do this by following the instructions provided in the rGPM package documentation.

Hi,

I use the ERA5-Land product and compare the hourly data with the monthly data of the same product ERA5-Land. This is a reanalysis, there is no forecast. I downloaded the data (monthly and hourly) two weeks ago. In theory, these datasets must be equivalent since one is the monthly mean of the other. See: https://essd.copernicus.org/articles/13/4349/2021/

Best,

Santiago

If possible applie Quantile Mapping in daily value of precipitation, fir extreme value. For mean regimen use delta method

Fateme Frootan if that didn't work with you then you can modify your chemical in defined media by using the model described in;

Thanks

Qasim Qayyum Kashif ok thank you

Precipitated calcium carbonate (PCC) and nano calcium carbonate (nano CaCO3) are both forms of calcium carbonate, but they are not the same thing.

PCC is typically produced by the reaction of calcium hydroxide and carbon dioxide, resulting in the precipitation of calcium carbonate crystals. These crystals are typically in the micron-sized range, meaning they are much larger than nano-sized particles.

Nano calcium carbonate, on the other hand, is characterized by its small particle size, typically less than 100 nanometers. Nano CaCO3 can be produced by various methods, such as precipitation, sol-gel, and gas-phase synthesis.

Therefore, PCC is not considered to be nano calcium carbonate, although it may be possible to produce nano-sized PCC particles using specialized techniques.

I usually go to Google and search for weather data for the location of interest. I can usually find the monthly values for max and min temperatures, precipitation depth, and number of wet days. I then enter that information into our online weather generator (https://forest.Moscow fst.wsu.edu) and generate a hundred years or so of daily stochastic climate to drive our erosion models. For example, here is the information for Cairo: https://www.holiday-weather.com/cairo/averages/. I can send you more information on this method if you are interested.

Keep the Ice cold methanol precipitant (with PHA & chloroform) inside the freezer for 10 days. You will be able to observe visible precipitations!

FTIR and RAMAN to get data

Hello Saya Bird,

the purification depends on the polymer and the side products/impurities, which you want to remove.

Additional purification methods might be following:

Dialysis; I used this to remove some salts, which could leave the polymer solution through the membrane of the dialysis tube, whereas the polymer remained in the tube.

Fractionated precipitation: I used this to separate blockcopolymers from homopolymers or different moecular weight fractions of the same polymer from each other. You add a non solvent to a polymer solution and the less soluble polymer (depending on their chemistry in the case of block copolymer) or the polymer with the higher molecular weight (in the case of different molecular weights) precipitates first as a polymer gel.

There are also methods, that require more elaborate equipment, like preparative GPC or separation by LCCC.

If your separation does not remove the impurities, maybe add the solvent slower (drop by drop, as you mentioned) and use another solvent (or non-solvent). Maybe you polymer precipitates so easily, that the impurities are trapped in your solid polymer. If the polymer precipitates slower the impurities may stay dissolved (similar to the case of fractionated precipitation).

The confirmation of your product also depends on the polymer. Maybe some groups on your monomer were changed by the polymerization, which could be detected by IR-spectroscopy.

For the chracterization of polyurethanes (as an example), remaining isocyanate groups can be titrated.

If you use a new method to obtain a known polymer, you can also compare it's properties with literature values (i.e. the glass transition temperature via DSC) to get a hint if the reaction might have worked.

There are plenty of complex and simple methods to characterize a polymer, but it depends on your polymer if you can use them.

Muhammad Saadullah Thank you so much for responding to my question. The information you explained to me was useful.

Hi,

I'm currently trying to do the same thing and I also get precipitation after a few days or immediately after thawing, and it gets worse with heating. Did anyone find a solution?