Liquids - Science topic

A solid may be melt by heating, but be careful for any decomposition. For percent concentrations you must specify "by weight", "by volume", "mole %", etc. In your case I suppose that it is by weight (solid in liquid). For example, 20% corresponds to 20 g in a total weight of 100 g of solution.

Hasan Altawil, regarding the chemical additives, I would like to know if there is a specific ratio for the amount of barium hydroxide and silver nitrate to the total volume of the NaOH solution.

Also, how should the additive be added to the solution? I need to know if the solution should be added gradually, drop by drop, or it is being poured all at once?

Additionally, what kind of filter should we use for the filtration of precipitated BaCl2 or AgCl?

Lastly, I want to know the effects of additives on the color, pH, and concentration of the final NaOH solution."

Please check the following article for more info related to Mercury and other liquid metals:

Thank you for the guidance, Professor E.A. Gawad. Best regard.

You can use the hot plate with a temperature probe.

If you do not have it, what you can do is gradually heat up your solution until it reaches 95 °C and record what is the temperature of a hot plate in that moment. You do this in a separate experiment of course. For this you only need a simple thermometer.

You are actually better off doing it that way than putting it through a freeze-thaw cycle. A freeze- thaw cycle can ceryainly do more damage to the product than a day of refridgeration.

thank you for help.

Additional interesting RG free access paper.

Mohamed abdelsatar Ibrahim

The dispersed system of solid cerium oxide nanoparticles is called a suspension, not an emulsion.

Here, concentrated oleate-coated cerium oxide nanoparticles (CeO2 NPs) with a uniform size have been produced by solventless thermolysis of cerium-oleate powder under low pressure at 320 °C and subsequently dispersed in hexane.For dynamic lighting scattering

Evaluating the liquid that emerges after PVA (Polyvinyl Alcohol) and boric acid cross-linking and gel formation involves analyzing its physical, chemical, and rheological properties. Here's a comprehensive approach: *Physical Properties:* 1. *Viscosity*: Measure using a viscometer (e.g., Brookfield DV-II+). 2. *Density*: Determine using a densitometer (e.g., Anton Paar DMA 500). 3. *pH*: Measure using a pH meter (e.g., Mettler Toledo Seven2). 4. *Temperature*: Record using a thermometer. *Chemical Properties:* 1. *FTIR (Fourier Transform Infrared Spectroscopy)*: Analyze functional groups and chemical bonds (e.g., PerkinElmer Spectrum 100). 2. *NMR (Nuclear Magnetic Resonance)*: Study molecular structure and interactions (e.g., Bruker Avance 400). 3. *GC-MS (Gas Chromatography-Mass Spectrometry)*: Identify volatile compounds (e.g., Agilent 7890B-5977A). 4. *ICP-OES (Inductively Coupled Plasma-Optical Emission Spectroscopy)*: Determine elemental composition (e.g., PerkinElmer Optima 8300). *Rheological Properties:* 1. *Dynamic Mechanical Analysis (DMA)*: Study viscoelastic behavior (e.g., TA Instruments Q800). 2. *Rheometer*: Measure shear stress, shear rate, and viscosity (e.g., Anton Paar MCR 302). 3. *Oscillatory Rheology*: Analyze storage and loss modulus (e.g., Malvern Kinexus Pro+). *Other Tests:* 1. *Gel Content*: Determine using solvent extraction (e.g., Soxhlet apparatus). 2. *Swelling Ratio*: Measure by immersing the gel in solvent. 3. *Mechanical Strength*: Evaluate using tensile testing (e.g., Instron 5967). 4. *Biodegradability*: Assess using standardized tests (e.g., ASTM D6954). *Sampling and Preparation:* 1. Collect the liquid emerging after cross-linking and gel formation. 2. Filter or centrifuge the liquid to remove any impurities or particles. 3. Store the liquid in a sealed container to prevent contamination. *Data Analysis:* 1. Compare the liquid's properties with those of the initial reactants. 2. Evaluate the effects of cross-linking and gel formation on the liquid's properties. 3. Correlate the liquid's properties with its potential applications. *Interpretation:* 1. Viscosity and density changes indicate cross-linking efficiency. 2. pH and temperature changes suggest reaction kinetics. 3. FTIR, NMR, and GC-MS data reveal chemical structure and interactions. 4. Rheological properties indicate gel strength and stability. By employing these evaluation methods, you can comprehensively characterize the liquid emerging after PVA and boric acid cross-linking and gel formation, gaining valuable insights into its properties and potential applications.

solid CO2 in acetone should freeze the materials

The whitish liquid observed from neem trees (Azadirachta indica) is often linked to infestations by sap-sucking pests such as aphids, whiteflies, and mealybugs. These pests invade the phloem, causing stress to the tree, which may result in the release of a milky-like fluid known as guttation fluid. This fluid might contain defensive compounds like azadirachtin, which can kill insects. Other causes of the white fluid could include fungal infections or environmental factors. More research on neem tree-pest interactions could help in promoting sustainable pest control methods and understanding the tree’s ecological behavior.

There is not a stright answer. When adding yeast to a mixture that's made from breaking down plant material, there are a few important things to think about. These include how much yeast you add, how much sugar is in the mixture, how acidic it is, how well the yeast turns sugar into alcohol, and how much stuff might be in there that could stop the yeast from working.If you get these things just right, the yeast will do a better job at making alcohol, which means you'll get more out of it in the end.

For most purposes, using a starting amount of yeast that's 5 to 10% of the total mixture is enough, especially if you're only interested in the final product and the stuff you're using to grow the yeast is the same as what you'll use to make the final product. Still it's important to consider the specific conditions of your fermentation. Factors like the type of yeast, what you're using to make the mixture, and how quickly you want the fermentation to happen can influence the best amount of yeast to use. Sometimes, you might need to adjust the percentage to get the best results.

However, if you want to study how the yeast grows and changes throughout the whole process, you should measure how much yeast you start with so you can keep track of how it grows.

Qiagen kits are suitable for almost all body fluids. it won't disappoint you..

Sir according to the study conducted by Kumaresan & Reetha (2011) "Liquid Azospirillum bioinoculant formulated with trehalose (10mM) promoted long term survival of Azospirillum followed by glycerol (10 mM) gum arabica (0.3%) and PVP (2%) and they supported 108 cells/ml up to 11 months of storage under ambient temperature (28°C to 32°C), whereas PEG (1%), PVA (0.5%) and control (lignite carrier) recorded the same population up to 8 months, 6 months and 5 months respectively."

I think this might be helpful to you.. I have also attached the link to the same article here for your kind reference:

You can mix boric acid and zinc sulfate with reaction temperature 130 ℃ and stirred in reactor about 2-3 hrs. you can get Zinc and Boron Micronutrient Fertilizers.

The regulatory and quality control requirements for liquid biofertilizers containing Azospirillum brasilense can vary significantly by region, but several key aspects are generally applicable:

Regulatory Framework

Quality Control Measures

Read more:

Thank you very much for your answer

Dear Maketaye,

a lattice parameter for fcc structure a=5.367Acorresponds to the solid phase of argon and is suitable for modelling solid argon only!

For simulating gaseous or liquid argon, you should not use a fixed lattice structure. Instead, you should set up a system with an appropriate density or use the NpT ensemble to allow the system to equilibrate to the correct phase.

For example plz check following:

#######################################

units real

atom_style atomic

variable Lx equal 10

variable Ly equal 10

variable Lz equal 10

region box block 0 ${Lx} 0 ${Ly} 0 ${Lz}

create_box 1 box

create_atoms 1 random 256 12345 box

pair_style lj/cut 10.0

pair_coeff 1 1 0.238 3.405

velocity all create 120.0 12345 mom yes rot yes dist gaussian

fix 1 all npt temp 120.0 120.0 100.0 iso 1.0 1.0 1000.0

thermo 100

thermo_style custom step temp press etotal density

dump 1 all atom 100 dump.liquid_argon.lammpstrj

run 10000

# Measure diffusion coefficient

compute msd all msd

fix 2 all ave/time 100 1 100 c_msd[4] file msd_liquid_argon.dat

# Measure thermal conductivity (Green-Kubo method)

compute myKE all ke/atom

compute myPE all pe/atom

compute myStress all stress/atom NULL

compute flux all heat/flux myKE myPE myStress

fix 3 all ave/correlate 10 100 1000 c_flux[1] c_flux[2] c_flux[3] type auto file J0Jt.dat ave running

variable scale equal ${kB}*temp/(vol*${dt})

variable k equal trap(f_3[3])*${scale}

thermo_style custom step temp v_k

run 100000

########################################

Hope it helps! :)

It is quite normal. Many compounds specially low melting solids take some time to solidify. Preserving the sample at low temperature can speed up crystalization. Presence of trace of moisture or impurities can also delay in the formation of solids from viscous liquids. Once you get a solid sample preserve it and in next time while preparing the same compound add few grains of this solids of first lot to the viscous liquid of second lot and scratch the sample with a glass rod or spatula. It may help solidification rapidly.

I find that questions asking for recommendations or "what other people use" may not provide YOU with suggestions that are applicable to YOUR own applications.

I am a professional scientific consultant in HPLC and MS systems and applications. Here is some quick advice that I provide to my consulting clients designed to save them the most money and time, plus move them towards their goals. (1) System choice should be tailored to the specific application, needs and training level. Best to first identify (or suggest) example compounds and what matrix they may be found in. Schedule a few days at two or three of the large instrument vendors application labs to run a few of them (3-5, no more) while you and your most experienced scientist (the person whom will actually use the proposed system and who has 10+ years of hands-on experience in industry using LC-MS/MS to analyze samples). This allows for on-site, hands-on time to see their Instrument expert use the equipment and SOFTWARE on sample types which are applicable to your needs. The money and time spent doing this upfront will save you thousands/millions of dollars; (2) Most down time on LC-MS systems is due to poorly trained operators not being able to discern if the problem(s) experienced are caused by the instrument or software (it usually is the operator). Never hire someone "out-of school" to run the system. You need someone with an industry background, preferrably different companies who maintained, operated and developed methods on a similar LC-MS/MS system. They should be a very technical and experienced liquid chromatographer first as a decade plus of HPLC experience is critical to use the LC-MS/MS. Very few people will meet this requirement; (3) Never purchase a used LC-MS/MS system (unless it is purchased by you directly from the manufacturer, not a third-party seller). A new system, installed by the vendor allows you to start off with a system that is known/proven to operate correctly vs spending years trying to get your used system "to-work".

I see so many clients make mistakes by not taking the needed time to select an instrument. Many select an instrument first, then have their untrained staff try to operate it and fail to show results (you can not learn how to use systems like these by "taking a class"). They spend huge amounts of money with no results. Years go by and they end up with poor quality instruments and still have untrained staff. 10+ years of professional training are needed (people do not figure this out on their own. That strategy leads to failure every time). Start by selecting a skilled operator first, then begin the process of selecting the instrumentation with your new team following the suggestions above.

Well, this is a tricky thing to answer...

First thing that comes to my mind is PDMS or Silicone oil, but you are looking for something volatile at the same time...

Consider to use a small chain alcohol, such as ethanol (non-reactive with xantoprene) and add a small quantity of PDMS or Silicone oil up to the lubrication consistency that you are looking for.

Hopefully there is a sweet spot between having the minimum residue and having enough lubrication.

I hope this helps you.

And if you found another way to solve it, I would love to hear it as well.

Greetings

Michael J. Benedik

Thank you so much

I will try this

Anuruddha Mishra My guess is that you want to disperse this material; not dissolve it. If you really want to dissolve it, then there are 2 main ways:

If the former (dispersion) then the 3 steps from a powdered material are wetting (the use of a surfactant as mentioned by John Francis Miller above), separation (the key and difficult step; sonication is the norm), stabilization, if rapid agglomeration occurs after relaxation of sonication (a zeta potential issue that may be solved either with an appropriate concentration of an ionic stabilizer - phosphate e.g. Calgon is normal for inorganic oxides - or sterically with a polymer e.g. 50 kDa PEG or PEI). More on dispersion in this webinar (free registration required):

Dispersion and nanotechnology

Isopentane pre-cooled with liquid nitrogen is generally considered the best method for freezing brain tissue for protein analysis:

This method balances rapid freezing with minimized risk of ice crystal damage and tissue cracking, ensuring the best preservation of proteins for subsequent ELISA analysis.

A DES is generally characterized by a lower melting point than that of the individual constituents. Most DESs are formed in a liquid state, which can be preserved also at room temperature. DES is typically prepared by mixing hydrogen bond acceptor (HBA) compound with a hydrogen bond donor (HBD). The interactions between the hydrogen bond donor and the hydrogen bond acceptor cause the charge of the compound to be delocalized and the lattice energy to decrease; consequently, the melting point decreases, which is why the mixture is referred to as a deep eutectic solvent. Deep eutectic solvents(DES) is a new type of environmentally green solvents.water contamination is not a problem for purpose and dries the ChCl very thoroughly, then weighs it quickly and so far it has worked very well.

Storing radioactive cell samples in liquid nitrogen for extended periods can sometimes lead to changes in cell surface marker expression, which might explain the shift in the CD45 positive population you observed. Here are some possible reasons for this phenomenon and suggestions to mitigate it:

### Potential Issues

#### 1. **Cryopreservation Effects**

- **Cell Membrane Integrity**: The extreme cold of liquid nitrogen can sometimes cause damage to cell membranes, affecting the binding of antibodies to cell surface markers.

- **Ice Crystal Formation**: Improper freezing rates can lead to the formation of ice crystals, which can physically damage cells and alter the expression of surface markers.

#### 2. **Freezing and Thawing Process**

- **Thawing Method**: Rapid or uneven thawing can cause cell stress and affect the integrity of surface markers. It's crucial to follow a consistent and controlled thawing protocol.

- **Cryoprotectant Use**: Ensure the appropriate concentration of cryoprotectants like DMSO is used. Incorrect concentrations can either be insufficient to prevent ice formation or toxic to cells.

#### 3. **Radioactivity Effects**

- **Radiation Damage**: Prolonged exposure to radiation, even at low levels, can cause cellular stress and alter cell surface proteins. Ensure that the level of radioactivity is within safe limits for the cells.

### Best Practices for Cryopreservation

1. **Optimized Cryoprotectant Protocol**

- Use 10% DMSO in combination with a suitable medium (e.g., FBS or a cryopreservation medium) to protect cells during freezing.

- Aliquot cells into cryovials at a consistent cell concentration (e.g., 1-5 million cells per mL).

2. **Controlled Freezing Rate**

- Use a controlled-rate freezer to gradually cool the samples to -80°C before transferring them to liquid nitrogen. A typical rate is -1°C per minute.

3. **Thawing Protocol**

- Thaw the cells rapidly by placing the cryovial in a 37°C water bath. Once thawed, immediately dilute the cells in pre-warmed medium to reduce the concentration of DMSO.

- Gently mix and then centrifuge to remove the cryoprotectant.

4. **Handling Radioactive Samples**

- Store and handle radioactive samples following all safety protocols to minimize any potential radiation damage to the cells.

- If possible, reduce the storage time of radioactive samples in liquid nitrogen to the minimum required.

### Recommendations for Flow Cytometry Analysis

- **Staining Procedure**: Ensure that the staining protocol is optimized for cryopreserved cells. Sometimes, slight modifications are needed compared to fresh cells.

- **Compensation and Controls**: Use proper compensation controls and unstained controls to accurately set gates and distinguish between positive and negative populations.

### Literature and Protocols

1. **Cryopreservation of Cells**:

- Mazur, P. (1963). "Cryobiology: the freezing of biological systems." Science, 138(3544), 1271-1279.

- Stacey, G. N., & Hartung, S. (2006). "Cryopreservation and banking of human ES cells." Nature Protocols, 1(1), 212-218.

2. **Flow Cytometry on Frozen Samples**:

- Perfetto, S. P., Ambrozak, D., Nguyen, R., & Roederer, M. (2010). "Quality assurance for polychromatic flow cytometry." Nature Protocols, 5(2), 445-456.

By following these best practices and protocols, you should be able to improve the viability and performance of your radioactive cell samples during cryopreservation and subsequent flow cytometry analysis.

Recently I came across this: "Plant tissues are ground (e.g. leaf, shoot, root, approximately 0.1 g) with 1 ml of the lysis buffer (0.5% CTAB, 1% EDTA, 2.5% Tris base and 5% NaCl) in a sterilised mortar and pestle, without liquid nitrogen."

I didn't try cause I use liquid nitrogen, but maybe it's useful for you. I attach bellow the link of the paper.

Without cryogenic a plastic pulverizer machine, also known as a plastic mill or grinder, is a mechanical device used to grind plastic materials into fine powders or particles of course you can make powder from plastic or change plastic to powder into different particle size by hashing plastic and crushing otherwise the powder metallurgy is process which is used to change the shape of metal from powder to part according to die of forming. The plastic polarizer machine are available in various size depending upon the requirements.

Well... it can be done, but it is NOT easy. Your question is also somewhat ambiguous: are you trying to analyse a metal/ligand complex which is inherently liquid, or is it in solution in a solvent of some kind?

The easiest case is if it's soluble in water at such a concentration that the analyte element concentration is around 1 mg/litre (some elements need a lot more than this, a few require less). If you're working in an organic solvent, you'll need to be able to add extra air to cope with the combustion of the solvent (which means that when you switch between samples, you have to work FAST, because the flame will tend to go out: I've tried it - it's possible but NOT easy!)

Please can you be more specific about what precisely you're trying to do.

Kanishka Rajoria, Ireri a Carbajal, Kossi Kabo, Thank you for sharing your experience. Yes, I resolved this problem. It recommends moss RNA extraction.

1. Do not use more than 7 days of cultured protonemata cells. (fresh moss)

2. Do not use too many protonemata cells. (one petri dish, 6/1)

3. Please be careful not to overlap culture in the media.

4. Select the light green color tissue, not the deep green moss.

I trust that these ideas will enhance the quality of the RNA.

Yes, Phosphoric acid as P2O5 52% Minimum and Potassium as K2O 34% Minimum

You may use the web tool to calculate

For any kind of fuel, the bomb calorimeter is the old fashioned way.

My HT115 with pJET growed ok in plates with that same concentration of antibiotics. It did grow much slower though. How are your competent cells and transformation protocols?

-->I am not sure where you got your HT115 colony but I would encourage you to keep the Tet, if your source is not 100 % sure (this is if someone donate it to you instead of buying it), until you get your glicerol stocks.

Intisar Abbas

Graphene oxide hydrogel is graphene oxide powder mixed with water. For some reason, your graphene oxide breaks when you take it out and separate it from an unknown solvent. You need to ask the right question. It is not yet clear what problem you are solving.

Use separatory flask

Suraj Kalia

We can only answer that when mixed, molecules with chromophore groups are formed. What groups are formed can be assessed after studying the IR and visible spectra.

Hi I am curious did you end up fixing this somehow? Having a similar issue with pin misalignment. Any help would be appreciated thanks!

Hi Abdelhak Maghchiche

I had trouble understanding some of the calculations you made. Please clarify if possible.

Thanks

*0.5 wt% means 5 grams of the desired substance in 100 ml of solution?

According to the following statement:

Volume of Span 80 = (0.5 wt% x 100 g) / (1.05 g/mL - 0.85 g/mL) ≈ 4.76 mL

* 1.05 g/ml is the density of mineral oil?

* What is 100 grams in the expression (0.5 wt% x 100 g)?

Although the calculations seem quite logical, but I could not reach the reported answers and I don't know what is the problem?

I understand storing very old samples can be confusing and expensive. But here is what I think. DNA samples, especially plasmids are the most stable of them all. When stored at -80, it will retain all its properties for >10 years. If there is really scarcity of space, then you can store at least one vial of each type and discard the rest. RNA samples when stored in trizol is the most stable, however storing them in molecular grade ethanol at -80 can preserve its properties upto a few years.

Cells are most stable at liquid nitrogen, however it needs regular refilling. Hence, my advice is to keep at least one box containing one vial of each cell line in liq. N2.

Proteins are the most unstable of them all. Cellular/tissue lysates or purified proteins can remain stable at -80 for at least a couple of years, but I am very doubtful of >10 years. It really depends on the quality of the sample and the running condition of the -80 freezer.

Dear Péter Gyarmati

Thank you for yor answer.

After reading several sources and discussing with colleges, I got the conclusion that a good liquid-bead proportion could be around 60% of the volumen of liquid used, which match quite well with your suggestion of cutting bead cc to half.

Not talking about proportion of liquid and beads, but total final volume. Do you know if is there any minimum amount of liquid can be used for bead beating in a 2ml vial? For example, would 400ul of liquid and 200ul of beads (total volume 600ul) be too little volume to lyse the cells?

Thank you in advance.

could you reformulate the question with more information of your objetive?

Best

The problem is characterized by so-called critical exponents. For example, the vapour or liquid density of a pure fluid along the vapour pressure curve can be described by |ρ - ρ_c| = B |T - T_c|^β in the vicinity of the critical point. It can be shown that any analytical equation of state yields β = 0.5 . The experimental value, however is about 0.33 . The departure is explained by long-range density fluctuations.

There are basically two ways to deal with this problem in EOS: (a) using an analytical EOS with so many terms that non-classical critical exponents are obtained in the experimentally accessible range (and classical ones where there are no experimental data); (b) introduce some nonanalytical terms.

Most of the latter attempts require that the location of the critical point is known exactly – a condition not fulfilled for real fluids. Moreover, most of these attempts cannot be generalized to mixtures, where there are critical curves (for binary mixtures), and sometimes more than one.

Hey there Rahul Sinha!

So, you're diving into the world of CO2 photocatalysis for liquid product synthesis – that's exciting stuff! I've got your Rahul Sinha back on optimizing your GC-FID method to nail down those quantifications and identifications.

First off, let's talk sample prep. You'll Rahul Sinha want to ensure your samples are well-prepared for analysis. This means proper extraction and concentration techniques to get the most accurate results.

When it comes to column selection, it's all about finding the right balance between resolution and analysis time. I'd recommend exploring columns with polar phases for better separation of your Rahul Sinha target compounds.

Now, onto detection parameters. You'll Rahul Sinha want to fine-tune your detector settings to ensure sensitivity and accuracy. Pay close attention to factors like temperature, flow rates, and injection volume to optimize your results.

Lastly, data interpretation is key. With the variety of compounds you'll Rahul Sinha be dealing with, it's important to establish reliable calibration curves and peak identification methods to confidently analyze your results.

Feel free to reach out if you Rahul Sinha need further assistance or have any questions along the way. Happy to help you ace this GC-FID analysis!

First of all take a certain amount of TTIB which will be in mL (liquid). By using formula of density ( d=m/V) find the mass of TTIB from given volume.

Then find how much mass of TiO2 is produced from total mass of TTIB produced.

Now calculate the percentage mass of dopant as compared to produced TiO2.

This may be due to strong interactional forces between the components of material. This also shows that the material is highly viscous and May be in gel form.

In order to choose between pre-emergent herbicide formulation in the dry or liquid form, a number of aspects need to be taken into account. While the dry formulations have longer shelf life and less storage and transport challenges making them good for long term use and fewer chances of spills, they require more careful mixing as well as having limited methods of application that can result in slow uptake. On the other hand, liquid-based formulations enable easier application and faster absorption into soil hence weed killing becomes quicker. They can be used in different ways but their lifespan is shorter with higher drift and spillage risks. One has to consider various factors like kind of herbicides being used, type of weeds being targeted, machinery required for applying it as well as surrounding weather conditions if this decision is going to be made. It would be necessary however to ensure proper reading alongside following manufacturer’s recommendations which might end up helping with how effective or safe an application process will go regardless of whether a product is liquid-based or not.

Colonel Sudhir Mudigere Rangappa

2 quotes from those greater than I:

'I think dry nanotechnology is probably a dead-end' Rudy Rucker Transhumanity Magazine (August 2002)

‘If the particles are agglomerated and sub-micron it may be impossible to adequately disperse the particle… ‘The energy barrier to redispersion is greater if the particles have been dried. Therefore, the primary particles must remain dispersed in water...’ J H Adair, E. Suvaci, J Sindel, “Surface and Colloid Chemistry” Encyclopedia of materials: Science and Technology pp 8996 - 9006 Elsevier Science Ltd. 2001 ISBN 0-08-0431526

What is the specific surface area of your material? If it's not more than 60 m²/cm³ then it can't be considered nano. There will be no free, independent, discrete particles < 100 nm in such a system. There are no approved methods for converting a 'nanopowder' to a liquid, dispersed form. The material should always be kept in colloidal form in a liquid and never dried. Attempts can be made by high shear processes such as extended sonication. Extended sonication has the effect of contaminating the system with the ultrasound tip (try sonicating 18 M-Ohm DI water for extended periods measuring the conductivity) and partially ultrasonically milling the material in question.

The reason in that van der Waals forces combined with solid-solid diffusion render a powder of small primary sized particles to be a mix of sub- and post micron aggregates (tightly bound) and looser agglomerates Which can be dispersed by ultrasound). For further information see these webinars (free registration required):

Dispersion and nanotechnology

Adhesion and cohesion

See the attached classic picture by Hans Rumpf of gold particles on an anthracene surface where that surface has been distorted and bent upwards toward the gold particles from these attractive forces.

While ULT freezers can be used to store cells at temperatures of -80°C or slightly below, you may need a cryogenic freezer if you need to replicate the cold temperatures achievable with LN2 without actually using LN2. Those can get down to around -150°C. I believe Thermo and PHCbi make some.

The corpus luteum is a temporary endocrine structure in the ovaries that develops after ovulation. It plays a crucial role in the menstrual cycle and early pregnancy by producing progesterone, which helps prepare the uterine lining for implantation and supports early pregnancy if fertilization occurs. There isn't a single "best model" of the human corpus luteum, as researchers may use various approaches depending on their specific research goals. However, there are several common models used in studying the corpus luteum: In vivo models, In vitro models, Animal models, and Computational model.

Dear Esteemed Colleague,

Greetings. I trust this message finds you well and advancing in your valuable research endeavors, particularly in the domain of lentiviral vector studies. Your inquiry regarding the storage of lentivirus in liquid nitrogen is both relevant and crucial for maintaining the integrity and efficacy of lentiviral preparations. Below, I provide a comprehensive analysis of lentivirus storage practices, with a focus on the use of liquid nitrogen.

Storage of Lentivirus

Lentiviruses are versatile tools in molecular biology and gene therapy research, used for delivering genetic material into cells. Preserving their infectious and functional capacities through proper storage is essential for the success of experimental outcomes.

Liquid Nitrogen Storage

Considerations and Best Practices

Conclusion

Storing lentivirus in liquid nitrogen represents a viable strategy for preserving viral integrity and infectivity over extended periods. Adhering to meticulous preparation, safety guidelines, and proper cryopreservation techniques will ensure the lentivirus remains a potent tool in your research endeavors.

Should you require further insights into lentiviral storage practices, handling, or applications, please do not hesitate to reach out. I am here to support your research efforts and facilitate your success in the field of lentiviral vector studies.

Warm regards.

This list of protocols might help us better address the issue.

Ayesha Khalil

1. If you distribute solid nanoparticles in water (solvent), then this process is called preparing a dispersed system, not a solution.

2. To quantitatively prepare such a dispersed system, you had to write the amount of solid phase in it.

3. To prepare 50 microliters of a 5% dispersion of silver nanoparticles in water, you must weigh 5 micrograms of nanoparticles, place them in a microtube and add 45 microliters of water using a micropipette.

4.how to cover solid quantity into liquid(microliter)?

To do this, it is necessary to place solid nanoparticles in a measuring microtube, melt them and determine the volume.

Try paraffine (= pure alkane) oil; they should be inert to gallium up to 200 °C, provided that no oxygen is present.

A liquid crystal is not exactly a bridge between solid and liquid states.

Actually, there is an ambiguity defining the two states. If one defines a solid by crystalline long range order (static, structure), liquid crystals are on the solid side. Instead, if one makes the distinction by viscosity or a (relatively arbitrary) relaxation time (dynamics), liquid cystals are liquid. Conversely, glasses are liquid or solid, repectively.

The common distinction between solid and liquid states is the dynamic definition. Then, glasses are "solid" and liquid crystals are ... "liquid"!

In theory, instead, glasses are studied within the formalism of liquid theory because presence or absence of periodicity induces important differences.

Beyond a critical point, a fluid shares properties of liquids (e.g. high density) and gases (absence of free surface).

There are other common intermediate states, like gels, emulsions, plymer melts, ...

Every classification is partly arbitrary...

She can use ASPEN Plus or DWSIM to get the activity coefficient at different temperature and composition.

Another crucial information may be supplied by the company concerning the type/name of the initiator used in the addition ROP of ethylene oxide. This is important in that end groups usually have their own intrusion in many properties and behaviors. Also you may ask if the PEG 100 has been the subject of further post- polymerization treatment. Best of luck in your work.

Hey there Ghazal Tuhmaz!

Alright, let's dive into why we're all about using nonionic liquids in the wire explosion plasma method for creating metal nanoparticles.

First off, nonionic liquids bring some serious perks to the table. They're like the cool, calm, and collected sidekick in this explosive process. Unlike their ionic counterparts, nonionic liquids don't carry an electric charge. This means they play nice with metals during the explosion phase without causing any unwanted reactions or disruptions.

Now, onto the wire explosion plasma method. Picture this: we're zapping a thin metal wire with a super high-voltage pulse of electricity. This sends shockwaves through the wire, causing it to literally explode into tiny droplets.

Here's where the nonionic liquid swoops in like a superhero. It acts as a stabilizer, surrounding those newly formed metal droplets and preventing them from clumping together like unruly magnets. This helps us maintain control over the size and distribution of our precious metal nanoparticles.

In essence, nonionic liquids are the unsung heroes of the wire explosion plasma method. They keep the chaos in check and ensure we walk away with beautifully dispersed metal nanoparticles ready to work their magic in various applications.

Hope that sheds some light on why we're all aboard the nonionic liquid train for this explosive endeavor! If you've got more questions or need further elaboration, don't hesitate to give me a shout. Cheers Ghazal Tuhmaz!

Sorry I cannot help

G. Bognolo

Sorry I cannot help.

G. Bognolo

Ghazal Tuhmaz Nonionic liquids are used in the wire explosion plasma method for metal nanoparticles due to their high thermal stability, anti-aggregation properties, tunability, and potential environmental benefits.

Good Question

Thank you Ulrich Deiters for your answer and valuable time.

thanks for your kind answer

Xun Wang Dissolving tin and antimony in citric acid solutions is challenging due to their specific chemical interactions. Tin dissolves, forming a passivating film, while white precipitates may occur due to SbCl₃'s limited solubility or insoluble antimony compounds. Precipitation can occur due to pH, concentration, complex formation, and temperature.

Could you be more specific with repect to the mixture? Does “supercritical” refer to vapour–liquid phase separation? Then you would probably look for a lab that can handle high pressures. Are you interested in cryogenic systems or in phase equilibria at high temperatures?

You could test a couple of different manufacturers' vials to see which ones cope with the stress of freezing. I experienced the opposite issue with heating polypropylene vials that had been gamma irradiated in the factory and found they melted at a lower than expected temperature. Try out a few vials and see if they crack or split when frozen (or the lids fail upon returning to room temperature). You may need to adjust sample volumes or pre-cool the sample before going into liquid nitrogen.

Best of luck.

Hello

The vacuum causes the water to boil at a lower temperature and evaporate

The connections in the vacuum cause no water to escape from the reaction vessel, so the water will remain as it is

During the reaction, you should see steam in the glass container

Microemulsions are thermodnamically stable, so if you want to break one you have to use pressure or temperature. Have you tried to heth or cool your emulsion? Mind you, when the emulsion breaks you loose the identity of the particle. If you want to just separate the nanoparticles and preserving their identity gravity separation is the only way. I seem to understand that you have already used ultracentifugation with some success. The other possibility is to build agglomerates of larger particles that should settle more quickly. If your system can tolerate you may try low concentrations of di or trivalent cations. Start with say 0.001 molar CaCl2 or AlCl3. If nothing happens go to higher concentraations,

Best regards

G Bognolo

My take is that starter culture preserved at 4oC for up to 24 hours will not have any significant population change. This is due to inactivation of microbial enzymes. However, if left for longer than this period, cell start entering a decline phase and therefore a lower population in the starter culture.

Of course Shubham Karpe, we can discuss the effectiveness of entrapping drugs within nanoparticles. The efficacy of entrapment is a crucial parameter in drug delivery systems, particularly when dealing with nanoparticles. It refers to the percentage of drug molecules successfully encapsulated or entrapped within the nanoparticles compared to the total amount of drug used during formulation. To determine the entrapment efficacy, we measure the total drug content before and after encapsulation, and calculate the difference between these amounts. This value is then expressed as a percentage by dividing it by the initial total drug amount and multiplying it by 100. The formula for calculating entrapment efficacy is:

Entrapment Efficacy (%) = [(Amount of Drug Entrapped / Total Amount of Drug Used) x 100]. It is essential to employ precise measurement techniques and reproducibility to obtain reliable results. Additionally, factors such as nanoparticle size, surface charge, and composition can significantly impact entrapment efficacy, and should be carefully optimized during formulation to achieve the highest entrapment efficacy.