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The above-mentioned various glass instruments may have a standard grinding mouth or a non-standard grinding mouth according to different applications. (5) The instruments used for gas operation refer to glass instruments used for the generation, collection, storage, processing, analysis, and measurement of gases: for example, gas generators, gas washing bottles, gas drying bottles, gas collection and storage Devices, gas processing devices, gas analysis and measurement devices, etc. (4) There are many types of tubes, rods, and glass rods. (3)

Basic operating instruments and devices: for example, for absorption, drying, distillation, condensation, separation, evaporation, extraction, gas generation, chromatography, liquid separation, stirring, crushing, centrifugation, filtration, purification, combustion, combustion analysis And other glass instruments and devices. So how to classify and manage laboratory glass instruments? Wuhan Jisi Instrument Equipment Co. (3)

Bottles refer to containers used to store solid or liquid chemicals, chemical reagents,

water samples, etc .Because of the wide variety of glass instruments, their wide range of uses and their different shapes, moreover, analytical laboratories in different professional fields need to use some special glass instruments. (2) Measuring instruments refer to glass instruments used to accurately measure or roughly measure the volume of a liquid: for example, measuring cups, measuring cylinders, volumetric flasks, burettes, pipettes, etc., Ltd. used to measure flow, specific gravity, pressure, temperature, surface tension, etc. (5)

Physical measuring instruments: For example, glass instruments used for testing pcr tube and plate color, optical density, electrical parameters, phase change, radioactivity, molecular weight, viscosity, particle size, etc. (2) Containers: such as dishes, bottles, beakers, flasks, tanks, test tubes, etc. (6)

The readers who have yellow Pipette Tip the previous story of this series have shared the interesting stories about the pH measurement of cosmetics. For different types of cream and lotion cosmetics, the specific experimental details will be different. Turning more interesting Centrifugation experiment In the two tables above, we can see that among the physical and chemical indicators of cream emulsion cosmetics, a significant test is the centrifugation experiment, which has been proven to test the stability

performance and shelf life of cream emulsion cosmetics. See this little guy above?

That's right, what Xiao O classmate wants to say is it! First of all, the lightweight and flexible shape  compact body will not take up too much space, coupled with ergonomic adjustment knobs and intuitive display panel design, more suitable for operators to complete independent and simple in the cosmetics laboratory Centrifugation experiment; Secondly, the full-featured nerve center dual safety control of adaptive imbalance monitoring system and overspeed detection can effectively avoid the safety accident of rotor flying, while the silent design can greatly reduce the noise of the centrifugation process, and create A quiet and comfortable experimental environment; Finally, the adaptable limbs adapt to 3 rotors + 7

different capacity centrifuge tubes (1. In this issue, we will look at one of the largest members of the cosmetics kingdom in the future: ream lotion products. B. The key methods, such as facial cleanser, body lotion, hair coloring lotion, etc. But don't look at this small bottle of lotion. Emulsification is a liquid-liquid interface phenomenon. Quality Standards for Cosmetic Products of Creams and Emulsions The inspection of finished cosmetics in China mainly includes sensory indicators, physical and chemical indicators, hygienic indicators, packaging and marking, and measurement, etc.5ml ~ 50ml),

plus the ultra-long range setting, up to 99 Hours 99 minutes. Type, structure, and performance have a lot to do with the size (dispersibility) of emulsion particles and the quality (stability) of the emulsion. As a type of cosmetics in close contact with our skin, the quality of cream and lotion cosmetics needs to be strictly cont

 That is, the number of fungal colonies in a petri dish is multiplied by the dilution factor of the petri dish inoculum. 2. Sterile water: a 45 mL sterile water triangle bottle with glass beads and a test tube containing 9 mL of sterile water. Equipment Sample: Fresh soil. Experimental steps (1) Experimental procedure 1 Prepare soil dilution solution: 1. A single colony is picked and inoculated on the slant medium.

Step 4: Remove the sample from the Jingxin mill, open the plastic can and pour out the sample. Under normal circumstances, the wooden structure of fir (fir, spruce, cypress) is crunchy. It is easy to grind with steel balls and steel cans. The requirement is to grind the xylem into powder, and then measure the heavy metals and annual rings in the wood by stable isotopes. .

The third paragraph: the specific grinding method of the experimental steps Step 1: the sample and XX ml of ground plastic cans Step 2: put the sample in the XX ml plastic cans, and then put the plastic cans on the Jingxin mill, step 3: Set the parameter grinding frequency XX HZ, and the time can be ground into a powder. It is still the same principle, put the sample and ceramic beads in a plastic jar, put it into the instrument, set the frequency and time, and then grind. (Attach the sample picture)

The second paragraph: Describe the research principle of the sample. The experimental results (comparison of grinding before and after putting), the grinding fineness of the powdered sample can meet the experimental requirements. Note: The samples must be lyophilized for more than XX hours in a lyophilizer. The wooden structure of fir (fir, spruce, cypress) is crisp. To remove the effect of heavy metals on the sample, ceramic Beads and plastic cans were used for experiments. Otherwise, the fibers in the wood are not easy to grind and pulverize, and the oil in the xylem sticks to the wall of the grinding tank and the beads..The first paragraph: Background knowledge. It is easy to grind steel cans by using Shanghai Jingxin multi-sample tissue grinder, but the teacher wants to remove the impact of heavy metals on the sample. Teachers of the School cryotubes of the Environment of Shaanxi Normal University need to do wood experiments

If you look up and then head down cryo rack after the probe is down, it may be because the template amount in the system is too high, it is recommended Reuse after dilution. I. Generally speaking, the fluorescence amplification curve can be divided into three stages: the fluorescence background signal stage, the fluorescence signal exponential amplification stage, and the plateau stage. Common housekeeping genes are beta-actin,

GAPDH, 18SrRNA and so on. 3) Specific primers:

The specific reverse transcription method is to use oligonucleotides containing the complementary sequence of the target RNA as primers. Add 30 ~ 50 mu; l of RNase-free water, stand still for 1min, shake for 30sec, and centrifuge immediately. To each tube, 2 times; qPCRTaqMix 12. 1. With this method, all RNA molecules in the system all serve as cDNA * strand templates, and PCR primers impart the required specificity during the amplification process.5ul to 25ul Mix well, 70 5 minutes at ℃, immediately ice bath 5 * buffer4.

It is particularly suitable for detecting the expression of multiple genes. Derivation of 2- △△ CT method (for details, see Real-time quantitative PCR and 2- △△ CT method for analyzing relative gene expression) Supplement: After DNaseI digests the DNA in the sample RNA, the sample needs to be extracted again with chloroform.5ul1. Take care not to touch the pellet. It can be used to detect whether rare genes are expressed and quantitatively detect the expression level of specific mRNAs from a very small number of cells.. Because Real-TimePCR has higher requirements on the quality of RNA samples, it is necessary to choose a suitable one before formal experiments.

There are two bright bands, 28S and 18S, without DNA band contamination. Centrifuge at 3.0ul dNTP (10mM) 2. 2- △△ CT method is a simple method to analyze the relative changes of gene expression in real-time quantitative PCR experiments. Centrifuge at 14000 rpm for 8 min at 4 ° C, and take the supernatant (about 250ul). Re-examine the amplification conditions or redesign and verify the primers. The key to doing the dye method is to find the appropriate primers and prevent pollution. Observe with a gel UV analyzer. Specific experiments The process is as follows:

Sample test process: 5ml Pipette tips combined with liquid chromatography, the mobile phase needs to be filtered through a membrane first, and the organic membrane and the water membrane need to be distinguished. Mass spectrometers in general laboratories perform major maintenance during long holidays. 3) After the pressure reaches the requirements, open the control box (RC Interface), hear a beep, open the software of MA soft and start the experiment setting.

It is necessary to periodically open the shock valve for about 20 minutes to shake the gas. Adjust the frequency of tremor based on the amount of detection. Because the mass spectrometer needs to be stable for more than 24 hours, frequent switching of the mass spectrometer will also accelerate the vacuum gauge contamination. Calibration is required after each power-up to use the mass spectrometer. Be careful not to lose parts during disassembly. ② Liquid chromatography-mass spectrometry (LC-MS) is the same, including liquid chromatography-quadrupole mass spectrometer, liquid chromatography-ion trap mass spectrometer, liqu

id chromatography-time of flight mass spectrometer

, and various Liquid chromatography-mass spectrometry-mass spectrometry. The internal cleaning and maintenance of the mass spectrometer is generally relatively rare. 4) When selecting different detectors for different scanning ranges, you can double-click the detector unit and a dialog box appears. 4) The QIC20 cooling filter should be cleaned regularly (every two months). The pump oil of the mechanical pump needs to be replaced regularly, usually once every six months. The mobile phase cannot use hard-to-volatile acids or salts, such as phosphates and borates.com/. , It means that you don't need to turn on the filament for the next experiment. Compared with chromatography, mass spectrometry has extremely high

environmental requirements. From the perspective of applications, mass spectrometers can be divided into the following categories: 1. Therefore, more and more laboratories are currently configuring mass spectrometry. 2) Turn off the pump and use the ▲ ▼ arrows to adjust the black bar display position to the Turbo Back option. Organic mass spectrometers are divided into different types due to their different application characteristics:

1. Before biotransformation, cryotubes methods or radioisotope labeling methods can be used to analyze and isolate possible metabolites, and use chromatographic-mass spectrometry and other methods to preliminarily predict the metabolites. At each time point, data for 6 animals (male and female) should generally be available. Now that the principles of non-clinical pharmacokinetic experiments have been clarified, let's take a look at the specific experiments involved. Dose selection: At least three dose groups should be set for pharmacokinetic studies in animals. 4.org. Number of test animals: It is best to take samples from the same test animal. Drug metabolism enzymes and transporters research

The in vitro test system is to evaluate the mechanism of drug metabolism enzymes and transporters, combined with in vivo tests, to comprehensively evaluate the drug disposal process. In vivo drug biotransformation can be considered concurrently with drug-time curves and excretion tests. Test animals: adult and healthy.

The picture comes from the network [1] 2. (2) Try to perform the test while the animal is awake.sogou. 6.4. Name, source, batch number, content (or specification), storage conditions, expiration date and preparation method, etc. Source network of pictures [2] 5. Today ’s content is here, and follow-up will continue. Samples collected from these tests are used to identify metabolites and determine concentration. Blood concentration-time curve 1.   amp; did =  so you must follow the following principles in the experiment to ensure the authenticity of the experiment! (1) the test purpose is clear; (2) the test design is reasonable; (3)

the analysis method is reliable; (4) the obtained parameters are comprehensive and meet the evaluation requirements; (5) the test results are comprehensively analyzed and evaluated; (6) the specific problems are specific analysis.com/d?query=%F4%CE%F 4% CE% B1% ED % C7% E9% B0% Famp; did = 10 # did9 [3] http://pic. Combining with plasma proteins It is recommended to carry out a comparison test of the plasma protein binding rate between animals and humans according to the animal species used by the Institute of Pharmacology and Toxicology. structure. 7.

Blotting hybridization Southern blot hybridization: gel ionizes DNA fragments digested with restriction enzymes, denatures the DNA on the gel and transfers single-stranded DNA fragments to a nitrocellulose membrane or other solid On the phase support, it is dried and fixed, and then reacted with the labeled probe of the corresponding structure at that time, and the color is developed by autoradiography or enzyme reaction, and the content of molecules of a specific size is detected. It can be used to analyze the restriction map of cloned genes, qualitative and quantitative analysis of genomic genes, gene mutation analysis and restriction length polymorphism analysis (RELP).

Northern blot hybridization: It evolved from Southern blotting hybrid method, and the tested sample is RNA. After formaldehyde or polyglyoxal denaturation and electrophoretic separation, it is transferred to a solid support and subjected to a hybridization reaction to identify the amount and size of a specific mRNA molecule in the group. This method is a commonly used method for studying gene expression, which can deduce the expression level of oncogenes.

Differential hybridization is the transfer of recombinant phage DNA from a genomic library to a nitrocellulose membrane, using two different types of cDNA probes (eg, reverse-transcribed cDNA from metastatic and non-metastatic cancer tissues) Hybridize to the DNA on the filter, and analyze the hybridization information at the corresponding positions on the two filters to isolate the differentially expressed genes.

It is suitable for china plastic tube factory of genes expressed by eukaryotes with less complex genomes (such as yeast), and the false positive rate is low. However, for very complicated genomes such as human beings, the percentage of expressed sequences is relatively low (only about 5%) due to the heavy workload, which is of little value. cDNA microarray hybridization refers to arranging cDNA clones or PCR products of cDNA in a high array and binding them to a solid support (such as a nylon membrane or an activated glass slide). Dot matrix, and then use a mixture of different DNA probes to hybridize the DNA on the microarray. Then, the fluorescence information, chemiluminescence, and confocal microscopy are used to scan the hybridization information on the microarray. It is more efficient, faster and cheaper than differential hybridization, and is suitable for large-scale analysis.