Drying apparatus for the preparation of liquid nitrogen, gas and mass spectrometric analysis of samples. It uses internationally recognized technology, usually nitrogen gas was blown surface samples were heated sample concentration. When this method has Province, easy to operate, easy to control until characteristics, can quickly get the desired results. QF-3800 device nitrogen blowing concentrated structural features: 1, I produced the QF-3800 nitrogen blowing device with good heat conductivity, heat evenly, is conducive to rapid heating and rapid temperature control. 2, nitrogen gas was blown to the surface of the sample to achieve an oxygen-free liquid concentrate of the sample. Blowpipe independent of each other, will not cause cross-contamination. 3, QF-3800 has a variety of holes and corresponding blow pin number to choose from. 4, QF-3800 anti-careless operation designed interior spilled liquid water receiving box to avoid damage to the internal circuitry. 5, a more uniform overall temperature accurately, the temperature detected by the sensor directly. 6, four digital display devices show the set temperature and the actual temperature. 7, a good instrument internal structure design makes the instrument can work long hours at a high temperature state of constant size indicators and technical parameters: Model QF-3800 temperature adjustment range ambient + 5 ℃ -100 ℃ temperature regulation accuracy is ± 0.1 ℃ ceiling temperature of 100 ℃ temperature protection to protect the set temperature deviation ± 5 ℃ heating block number of holes 12 holes / 24 holes heating power 350W power supply voltage 220V / 50HZ