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How does a melting point and melting rate apparatus perform melting point measurements?

The melting point and melting rate tester holds a significant position in the chemical industry and pharmaceutical research. How does a melting point and melting rate tester perform melting point measurements? 1. Input the desired starting temperature using the temperature control knob. The set starting temperature should be lower than the melting point of the substance being measured (not exceeding 280℃). 2. Turn on the power. Observe the light through the viewing window; the silicone oil is being stirred by the motor, indicating that the instrument is on. The display will show the current oil bath temperature. The instrument system will automatically control the temperature to reach the preset temperature and automatically balance. If the preset temperature needs to be modified, the required preset temperature data needs to be re-entered. Click the "Place" button. 3. Preheat the instrument for 20 minutes. Insert the capillary tube containing the substance to be measured through a small hole at the inlet into the oil bath tube (the capillary tube must be carefully inserted and removed, and must not be bent). 4. Select the heating rate according to the needs. Press the corresponding button; a light indicator on the upper left will light up, indicating that the instrument has entered a linear heating operation state. The four-stage linear heating rate buttons can be changed at any time. After heating, obtain a preliminary melting point range, and then perform precise measurement. 5. Observe the melting process of the sample in the capillary tube through the viewing window. When the melting

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Operating procedures for a melting point and melting rate tester

The melting point and melting rate tester is designed according to the specified melting point detection technology method. The instrument uses electronic information technology to achieve internal control of the temperature program, and displays the initial melting point and final melting point digitally. The circuit uses a linear correction platinum resistor as the detection element, realizing fast "starting temperature" setting and four selectable linear heating rates. The instrument can use the specified capillary tube as the sample tube, and observe and analyze the melting process of the sample in the capillary tube through a high-magnification magnifier, which is clear and intuitive. According to the definition of physical chemistry, the melting point of a substance is the temperature at which the substance changes from a solid to a liquid state. In the field of organic chemistry research, melting point determination is a basic technical means for identifying the cultural properties of substances, and it is also one of the important methods for purity determination. Therefore, the melting point apparatus plays an important role in the chemical industry and pharmaceutical research, and is an indispensable instrument for the production of organic crystalline substances such as pharmaceuticals, spices, and dyes. Operation of the melting point and melting rate tester 1. Preparation before use Place the heating container (beaker) containing the solution in the heat transfer process on the heating furnace of the melting point and melting rate tester, and insert the thermometer of the required material melting point into a thermometer fixing hole, so that the bottom end of the thermometer is 2.5 cm above the heating surface (heater).

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Precautions for Melting Point and Melting Rate Tester

Melting Point and Melting Rate Tester Precautions: 1. The melting point instrument should be placed in a dry, dust-free, and well-ventilated laboratory environment to avoid excessive humidity and dust pollution, which can reduce the service life of the melting point instrument. The instrument must be usable with corrosive liquids such as acids and alkalis; 2. During the capillary sampling and analysis process, care should be taken to avoid capillary breakage and hand injuries. If the sample produces toxic gases after decomposition, the instrument should be tested in a fume hood. During the test, avoid contact with the heating components to prevent burns; 3. After using the instrument, allow the temperature to drop to room temperature. Before using the instrument, check whether the test tube sleeve and furnace body are correctly assembled; check whether the light source output data is good. Automatic Melting Point Instrument: The automatic melting point instrument is the development trend of the entire instrument. No matter how bleak the reality is, the future will always be resolved. Therefore, a supplementary introduction to the automatic melting point instrument is provided here. Features of the Automatic Melting Point and Melting Rate Tester: 1. Integrated design, compact structure, easy to transport and place; 2. Color touch screen, more convenient operation, easy to observe the sample change curve in real time; 3. Can be connected to a computer, results are easy to store and query; generally linear heating, can meet a variety of heating options, including the following three temperature control and detection management systems

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Characteristics of a melting point and melting rate tester

The melting point and melting rate tester can be used as a substitute for silicone oil melting point testers in the pharmaceutical industry: the melting point and melting rate tester has limitations on samples, and colored samples after melting are unsuitable; the melting point and melting rate tester can only effectively measure melting and provide a reference for the initial melting results; the method specified in the pharmacopoeia is the silicone oil method. The fully automatic melting point detector has the advantages of high degree of automation and high detection efficiency. I. Characteristics of the melting point and melting rate tester: 1. Integrated design, compact machine, simple transportation and placement. 2. The color touch screen makes operation more convenient, and the sample change curve can be observed in real time. 3. It can be connected to a computer, and the results are easy to store and check; usually, it is linear temperature rise to meet various temperature rise options, including three separate temperature control detection systems, which can simultaneously measure three samples with different melting points. The cooling speed is less than 7.5 minutes, and the sample testing speed is fast. II. Precautions for using the melting point and melting rate tester: 1. Dry the sample in advance and grind it into powder with a mortar. The capillary tube must be filled firmly, with a height of 3mm. When the capillary tube is connected to the instrument, the contaminants on the outer surface of the capillary tube must be cleaned to prevent the instrument from being contaminated, which may lead to detection failure. If the capillary tube breaks or cracks during the test, the power should be immediately cut off and the

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Operating procedures for a melting point and melting rate tester

According to the definition of physical chemistry, the melting point of a substance is the temperature at which the substance changes from a solid to a liquid. In the field of organic chemistry, melting point measurement is a basic means of identifying the properties of a substance and is also an important method for purity testing. Therefore, melting point and melting rate testers play an important role in the chemical industry and medical research, and are indispensable in the production of drugs, fragrances, dyes, and other organic crystalline substances. I. The operating steps of the melting point and melting rate tester are as follows: 1. Preparation before use Place the heating container filled with the temperature transfer solution on the heating furnace of the melting point and melting rate tester, and insert the thermometer with the required melting point into the fixed hole of the thermometer, so that the bottom of the thermometer bulb is more than 2.5 cm above the heating surface, and the liquid level of the temperature transfer solution is approximately near the immersion line of the thermometer. 2. Startup Turn off the power switch, turn the voltage regulator clockwise, and heat the temperature transfer liquid. Turn on the "stirring" switch of the melting point and melting rate tester to start stirring the stirrer in the temperature transfer solution. 3. Measurement operation When the temperature of the temperature transfer solution rises to 10℃ below the lower limit of the specified melting point, turn the voltage regulator to increase the temperature rise rate by 1.0~1.5℃ per minute (for simultaneous melting and decomposition)

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Testing principle and selection of melting point and melting rate tester

Melting point is the equilibrium temperature of a solid and liquid substance under atmospheric pressure. It is measured by the temperature increase of a crystalline substance from solid to liquid and is recorded as the melting point. Melting point is an important method for identifying substances and determining the purity of substances. Therefore, melting point apparatus plays an important role in the chemical industry and medical research. Pure solid substances generally have a fixed melting point and a short melting range, generally not exceeding 0.5-1℃, which can be used to determine the purity of the substance and identify unknown substances. Mix the unknown substance with a known substance and measure the melting point. If the melting point does not change and the melting point range does not exceed 1℃, it can usually be considered that the two are the same substance. This method is called the mixed melting point method. At this stage, the main method for testing the melting point is to use a melting point apparatus for measurement. The manufacturing standard of the melting point apparatus is the national standard JJG 701-2008 verification procedure. Melting point apparatus is popular with users for its simple operation and clear results, especially fully automatic melting point apparatus does not require laboratory personnel to monitor at any time. Currently, there are many types and brands of melting point apparatus on the market. The following aspects can be referred to when selecting a suitable melting point apparatus: 1. Testing conditions of the sample: Powder samples can use a melting point apparatus based on capillary melting point measurement method, which can

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Functions of continuous casting slag protection

In the continuous casting process, after the continuous casting flux is added to the mold, it is heated and sintered and melted on the steel surface to form a liquid slag layer. When the mold powder near the liquid slag layer does not reach the melting temperature, it has been sintered into a transition layer. Above the transition layer is the original slag layer. This is the three-layer structure of the tundish powder that we usually call—liquid slag layer, sintered layer, and original slag layer. The liquid slag and liquid steel together form a meniscus near the crystallizer wall. Under the action of crystallizer vibration, gravity, and capillary adsorption, the liquid molten slag flows into the gap between the crystallizer wall and the billet shell through the meniscus to form a slag film. The consumption of the liquid slag pool and liquid slag on the steel surface between the crystallizer wall and the billet shell forms a dynamic equilibrium. The functions of continuous casting flux are introduced below: 1. Heat insulation to reduce heat loss of molten steel The continuous casting flux used for continuous casting must have good heat insulation properties, which can inhibit the formation of bridges and crusts in the crystallizer during continuous casting, increase the meniscus temperature, make the shell grow stably at the meniscus, and make the radius of curvature of the meniscus large. With the increase of the radius of curvature of the meniscus, the bubbles and oxide inclusions floating from the molten steel at the bottom of the crystallizer are not easily captured by the meniscus, and it is easier to float to the liquid slag layer, making the molten steel cleaner. 2. Isolate air to prevent secondary oxidation

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The influence of the melting point of continuous casting slag protection

The thickness of the protective slag layer is related to the consumption of continuous casting slag. The lower the viscosity of the continuous casting slag, the higher the flow rate, the better the lubrication effect on the slab, and the higher the melting speed required. Even in the same mold, the thickness of the slag layer varies in different positions. Usually located at the very deep part of the outlet, a wider and thinner surface and a thinner and narrower surface. Currently, there is little research on interfacial tension, but it is one of the factors that must be considered in the development of slag protection. Increasing the viscosity is also beneficial to improving the surface tension, but it is not conducive to heat conduction, which can be solved by lowering the melting point of the continuous casting slag. The following introduces the influence of the melting point of continuous casting slag: 1. Melting temperature The melting temperature of the flux has a great influence on the slag film thickness and mold heat flow. The slag film at the bottom of the crystallizer is thicker than that at the top, but the thickness increases with the increase of the melting point. The melting temperature of the continuous casting slag directly affects the thermal resistance of the slab and the slag film. The higher the melting point, the better the heat resistance of the slag film. In addition, as the temperature of the protective slag increases, the thickness of the protective slag film decreases, and the melting temperature of the crystallizer is extremely high, which is related to the critical thickness and drawing speed of the billet. For a given critical billet thickness, the faster the drawing speed, the lower the melting temperature. 2. Melting rate Continuous casting slag not only controls the thickness of the slag layer, but also

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Luoyang Turner High Temperature Instrument Co., Ltd.

+86-400-880-7095
Sales (same as WeChat):18695992058
Contact:+86-379-69755886
Address: South Section of Shuangxiang Road, Luoxin Industrial Cluster, Luoyang City, Henan Province
Email:tnkinstrument@163.com

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