![]() ![]() Bacteria resistance inoculation equipment.Microbial collection and filtration equipment.Small tangential flow ultra filtration system.Vacuum Constant Temperature Drying Case.Units with melting point standards as temperature transfer standards can correct the results according to the readings of adjacent standards. The initial melting point reading of the reference sample is used as the assessment basis. If there is a reference sample, the reference sample can be measured first, and a certain initial temperature and heating rate can be selected for comparative measurement according to the requirements. After measuring the sample with a higher melting point, measure the sample with a lower melting point, and directly input the instrument with a lower initial melting point temperature to automatically cool down. Generally, the best test conditions should be determined by experiments. The linear heating rate should be 1 ℃/min, the initial temperature should be 3 ℃~5 ℃ lower than the melting point, the linear heating rate should be 3 ℃/min, and the initial temperature should be 9 ℃~15 ℃ lower than the melting point. It is required to formulate certain specifications. The measurement results are inconsistent with different linear heating rates. If the capillary tube is broken or broken during the test, it should be powered off and taken out immediately.Ģ) In the sample test, the height of the same batch number should be consistent to ensure the consistency of the test results Fill 5 pieces in the same batch, remove the maximum and minimum values after determination, and average the intermediate values to reduce experimental error ģ) The test temperature shall not exceed the operating temperature range of the instrument (<300 ℃). ![]() It is necessary to remove the contaminants on the outer surface of the capillary tube when the capillary tube is connected to the instrument, to prevent contamination of the instrument, which may lead to failure of detection. The capillary tube must be filled firmly with a filling height of 3 mm. Precautions for Using the Automatic Melting Point Meterġ) The test sample is dried in advance and ground into powder by mortar. Before the instrument is used, check whether the tube sleeve is assembled with the furnace body Check whether the light source output is good. During the test, avoid contacting the heating part to prevent scalding ģ) After the instrument is used, the temperature drops to room temperature. If the sample to be tested generates toxic gas after decomposition, the instrument shall be put in the ventilation kitchen for testing. The principle of the instrument is acid, alkali, and other corrosive liquids Ģ) During capillary sampling, pay attention to avoid capillary fracture and hand injury. ![]() Precautions for Use of Melting Point Meterġ) The melting point meter shall be placed in a dry, dust-free, and ventilated laboratory environment to avoid excessive humidity and dust pollution and reduce the service life of the melting point meter. The reference materials commonly used in the calibration of melting point meter are naphthalene (final melting 80.6 ℃), adipic acid (final melting 152.9 ℃), and anthraquinone (final melting 285.7 ℃). Due to the large error caused by long-term use and seasonal temperature difference, the verification is also performed once a year. The melting point meter needs to be verified when it is turned on for use or has been used for one year. Test Accuracy, Repeatability of Test Results, and Test Range Are the Reference for Selecting a Melting Point MeterĪccording to the actual needs, the higher the accuracy and repeatability, the better after meeting the measurement range. For sheet or block samples, a micro melting point meter can be used. The melting point meter based on the capillary melting point measurement method can be used for powder samples, and the visual melting point instrument or automatic melting point meter can be determined according to specific indicators such as whether the sample is transparent after melting, the initial melting of the sample, and the melting range.
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