The operating steps of the video melting point instrument

The melting point instrument is designed in accordance with the melting point detection method specified in the pharmacopoeia, and the instrument uses electronic technology to achieve temperature programming, initial melting and final melting digital display
.

A linear-corrected platinum resistor is applied as the sensing element, and an electronic circuit is used to achieve fast "start temperature" setting and a four-stop selectable linear heating rate
.

The instrument adopts the capillary tube specified in the pharmacopoeia as the sample tube, and observes the melting process of the sample in the capillary through a high-magnifying glass, which is clear and intuitive, and is an ideal melting point detection instrument
for pharmaceuticals, chemicals, dyes, spices, rubber and other behaviors.

Operational steps of the video melting point instrument: Preparation before use Note: Before entering the formal test, the preparation work
before use must be carried out.

1.
Silicone oil infusion with a syringe (attachment) to absorb silicone oil (attachment) 10ml from the spill outlet injection, repeat 6 times, a total of 60ml of silicone oil injection, and then the oil spill bottle on the spill outlet (such as long-term measurement of melting point below 90 °C, distilled water can be used instead of silicone oil).
2.
Replacement of oil bath pipe First remove the oil spill bottle, and then remove the side plate; Reach into the instrument box with your hands, support the oil bath pipe with one hand, pull down the spring with the other hand, and then take out the oil bath pipe vertically and downward, and when taking out the oil bath pipe, you must be careful to avoid glass damage
.

Load the tubing into the instrument and proceed in the reverse order of the
above methods.

1.
Purpose Standardize the operation of the instrument of the analyst and ensure the normal use
of the analytical instrument.

2.
Scope This operating procedure applies to all analytical instruments
of this model.

3.
Basic operation 3.
1 Loading 3.
1.
1 Place the sample in a porcelain mortar and gently crush it into as fine a powder as possible to obtain a uniform sample
.

3.
1.
2 Take one or more clean, dry melting point tubes, insert the opening end into the sample, and load the sample
.

3.
1.
3 Take a dry glass tube about 0.
8 meters long, stand upright on the glass plate, and drop the melting point tube containing the specimen at least 20 times in it, so that the sample in the melting point tube is tightened to 3-4mm high
.

If two samples are measured at the same time for comparison, the height of the samples should be consistent to ensure consistency
in the measurement results.

3.
1.
4 The sample measured is easy to decompose or dehydrate, and the other end of the melting point tube should be melted
.

3.
2 Melting point determination 3.
2.
1 Turn on the instrument power switch, preheat for 10min, set the starting temperature and heating rate
.

3.
2.
2 Insert the melting point tube into the sample socket, hold it for 3-5 min, press the "Heat Up" button to start the measurement, and the instrument panel automatically displays the melting curve
.

3.
2.
3 According to the melting curve, read out the initial melting temperature and the final melting temperature
.

3.
2.
4 After the furnace temperature drops to the starting temperature, repeat the measurement and read the arithmetic average value as the measurement result
.

The difference between the average of the initial melting temperature and the final melting temperature of the two measurements is not more than 1 °C
.

3.
3 Shut down 3.
3.
1 Set the starting temperature of the melting point instrument to 30 °C, and turn off the power switch
of the melting point instrument after the instrument temperature reaches the set temperature.

4.
Precautions 4.
1 The sample must be dried and prepared and loaded strictly according to the requirements
.

4.
2 The quality and consistency of sample loading will directly affect the accuracy of the measurement reading, "poor loading" may lead to trough or long-distance discontinuity of the melting curve, and the measured value at this time is for reference
only.

4.
3 The maximum heating temperature of the melting point instrument is 300 ° C, so the starting temperature should not exceed 300 ° C, and often the use of the instrument at high temperature will cause the instrument to be not sensitive
.

4.
4 Before the melting point tube is inserted into the instrument, the outer tainted substances are removed with a soft cloth, otherwise the scale will accumulate under the socket after a long time, resulting in poor heat transfer and inaccurate
melting point detection.

4.
5 During the loading process, bring gloves to prevent irritating sample powder from sticking to the hand
.

4.
6 After use, the melting point tube cannot be discarded at will, and must be placed in a special box for unified treatment
.