Biological reagent (BR: Biological reagent)
It involves the classification of chemical reagents.
China's reagent specifications are basically divided into purity (how much impurity content), a total of high purity, spectral purity, benchmark, spectroscopic pure, excellent grade pure, analytical and chemical purity. The state and the competent authorities promulgate three main types of quality indicators: pure, graded pure and chemically pure.
(1) Excellent grade (GR: Guaranteed reagent), also known as first grade or guaranteed reagent, 99.8%. This reagent has the highest purity and lowest impurity content, suitable for important and precise analytical work and scientific research work, using green bottles. sign.
(2) Analytical purity (AR), also known as secondary reagent, has a high purity of 99.7%, which is slightly better than excellent grade. It is suitable for important analysis and general research work, using red bottle label.
(3) Chemically pure (CP), also known as tertiary reagent, â‰¥ 99.5%, the purity and analytical purity are quite different, suitable for industrial and mining, general analysis of schools. Use a blue (dark blue) label.
(4) Experimental reagent (LR: Laboratory reagent), also known as a four-stage reagent.
In addition to the above four levels, there are currently on the market:
Benchmark Reagent (PT: Primary Reagent): It is used as a benchmark and can be directly prepared into a standard solution.
Spectral pure reagent (SP: Spectrum pure): indicates that the spectrum is pure. However, since the organic matter is not displayed on the spectrum, the main component may not be 99.9% or more, and care must be taken when using it, especially when it is used as a reference material.
A reagent with a purity much higher than that of a pure grade is called a high purity reagent (â‰¥ 99.99%).
At present, the specifications of chemical reagents produced by foreign reagent factories tend to be classified according to their uses. The common ones are as follows:
Biochemical reagent (BC: Biochemical)
Biological reagent (BR: Biological reagent)
Biological stain (BS: Biological Stain)
Complexometric titration (FCM: For Complexometry)
For chromatography (FCP: For chromatography purpose)
Fluorescence analysis (FIA)
For microscope (FMP: For microscopic purpose)
For synthesis (FS: For synthesis)
Gas chromatography (GC: Gas chromatography)
High Pressure Liquid Chromatography (HPLC)
Indicator (Ind: Indicator)
Infrared absorption (IR)
Liquid chromatography (LC)
Nuclear magnetic resonance (NMR)
Organic Analytical Standard (OSA)
For analysis (PA: Pro analysis)
Pract: Practical use
(Pure purum pure)
Puriss (Purissmum special pure)
Industrial Tech: Techincal grade)
TLC (Thin Layer chromatography)
Spectroscopic pure, optically pure, pure spectrophotometric pure (UV: Ultra violet pure)
Everything You Need To Know About LED Lighting
LEDs are a simple invention with huge potential to change the lighting industry for the better. Don`t know much about them? Here are three big things you need to know to get your feet under you:
1.What Does LED Stand For?
2.LED stands for light-emitting diode.
A diode is an electrical device or component with two electrodes (an anode and a cathode) through which electricity flows - characteristically in only one direction (in through the anode and out through the cathode). Diodes are generally made from semi-conductive materials such as silicon or selenium - substances that conduct electricity in some circumstances and not in others (e.g. at certain voltages, current levels, or light intensities).
1.What is LED Lighting?
2.A light-emitting diode is a semiconductor device that emits visible light when an electrical current passes through it. It is essentially the opposite of a photo-voltaic cell (a device that converts visible light into electrical current).
Did You Know? There is a similar device to an LED called an IRED (Infrared Emitting Diode). Instead of visible light, IRED devices emit IR energy when electrical current is run through them.
1.How Do LED Lights Work?
2.It`s really simple actually, and very cheap to produce, which is why there was so much excitement when LED lights were first invented!
The Technical Details: LED lights are composed of two types of semiconducting material (a p-type and an n-type). Both the p-type and n-type materials, also called extringent materials, have been doped (dipped into a substance called a [doping agent") so as to slightly alter their electrical properties from their pure, unaltered, or [intrinsic" form (i-type).
The p-type and n-type materials are created by introducing the original material to atoms of another element. These new atoms replace some of the previously existing atoms and in so doing, alter the physical and chemical structure. The p-type materials are created using elements (such as boron) that have less valence electrons than the intrinsic material (oftentimes silicon). The n-type materials are created using elements (such as phosphorus) that have more valence electrons that the intrinsic material (oftentimes silicon). The net effect is the creation of a p-n junction with interesting and useful properties for electronic applications. What those properties are exactly depends mostly on the external voltage applied to the circuit (if any) and the direction of current (i.e. which side, the p-type or the n-type, is connected to the positive terminal and which is connected to the negative terminal).
Application of the Technical Details to LED Lighting:
When a light-emitting diode (LED) has a voltage source connected with the positive side on the anode and the negative side on the cathode, current will flow (and light will be emitted, a condition known as forward bias). If the positive and negative ends of the voltage source were inversely connected (positive to the cathode and negative to the anode), current would not flow (a condition known as reverse bias). Forward bias allows current to flow through the LED and in so doing, emits light. Reverse bias prevents current from flowing through the LED (at least up until a certain point where it is unable to keep the current at bay - known as the peak inverse voltage - a point that if reached, will irreversibly damage the device).
While all of this might sound incredibly technical, the important takeaway for consumers is that LEDs have changed the lighting landscape for the better, and the practical applications of this technology are almost limitless. To learn about why LEDs might be a good fit for your business.
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