In the 21st century, the level of industrialization has developed rapidly, but the natural environment and ecology on which human beings depend for it have been severely damaged. There are a lot of toxic and harmful gases, smog, acid rain, PM2.5, etc. in the air. Investigating NO_x^-based toxic gases, the market demands sensors that efficiently and accurately detect and prevent toxic and harmful gases.

Tungsten containing mesoporous materials have nano-scale homogeneous pore structure and huge surface area. They are a good catalyst carrier. By introducing active components into mesoporous materials, they can provide the active sites needed for catalytic reaction. They have shape-selective catalytic properties and are typical micro-reactor.

With the development of society, the requirement for materials is higher and higher. In some application fields, materials are required not only to have flexibility and strength, but also to have certain hardness and wear resistance, such as cutting tools in mechanical processing, drills for deep energy exploration, dies used in mechanical manufacturing and cylinder block of engine, etc.. For this reason, people try to use surface modification technology and surface coating technology to not only maintain the high strength and toughness of the material matrix, but also give play to the advantages of super-hard, super-strong and wear-resistant surface coating, thus greatly improving the durability and adaptability of the material.

Ammonium dithiotungstate (NH₄) ₂WO₂S₂ is an important thiometallic ammonium salt. After thermal decomposition, transition metal chalcogenide tungsten disulfide WS₂ can be obtained. It can be used in the synthesis of tungsten iron sulfur cluster compounds, semiconductors, superconductors, photoelectrochemical solar cells, hydrogen storage materials and electrode materials. It has good application and is the precursor of coal liquefaction and heavy oil hydrogenation catalysts. It can also be used as raw materials for the preparation of supported and non-supported tungsten sulfide hydrogenation catalysts. Therefore, it is of great significance to develop a high yield method for the preparation of high purity ammonium dithiotungstate.

Recently, the United States is looking around for alternatives to China's rare earths. In addition, a hurricane hit the US state of Florida, causing damage to almost half of the F-22 aircraft in the base. It seems that the "Eagle Eye" filmed by NASA is not only "eyelid" and "eyes", but the power is also sufficient. Worse, these fighters are "invisible", so that the current count of damage is still in progress. Up to now, there are more than 20 damaged points. According to military experts, is this loss worth hundreds or even thousands of Lamborghini? It seems that this loss is a bit big. So, now, it is estimated that the F-22 production line is waiting for the rare earth to “open the pot”.

Structural ceramics have maintained a strong and sustained growth in the past few years. This growth in demand stems not only from the growth of many different applications, but also from the exploration and attention of people to the science of ceramic materials. As demand continues to grow, people need stronger, more durable, lighter, and more heat-resistant materials to accomplish more impossible tasks. Material manufacturers must seek new innovative processes to produce the next generation of ceramics.

The hexagonal tungsten oxide has attracted much attention because its single crystal has an empty hexagonal space tunnel structure. W in the compound exists in the mixed valence states of W₆⁺, W₅⁺ and W₄⁺, thus making the charge balance of the compound as a whole. This unique spatial structure and special valence state make it have good optical effect.

Spherical tungsten powder is widely used in powder metallurgy processes such as preparation of porous materials, thermal spraying and injection moulding. Porous tungsten prepared with spherical tungsten powder has more uniform pore, so it is gradually replacing conventional tungsten powder to make porous tungsten components, such as cathode of high power pulse microwave tube, barium tungsten cathode of electron tube, sweating material of rocket, carrier of catalyst or catalyst, etc.

You are concerned about the news that "the Chinese have broken through the Western blockade of China and won the championship for the third time". Things are like this. Recently, the thin film optical laboratory of the Key Laboratory of Laser Materials of the Chinese Academy of Sciences, affiliated to the Shanghai Institute of Optics and Fine Mechanics (Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences) successfully developed a laser reflective film module, and for the third time won the fundamental frequency laser reflection. The International Competition for Laser Damage Thresholds for Thin Film Modules, the first time to win and the second to win in 2012 and 2013. They gradually seized and maintained the number one in the world, realizing the leapfrog development of China's high-power laser thin film technology. As for the middle blank period (2014~2017), Shanghai Optics Machinery Co., Ltd. did not participate in this international competition at the request of the relevant state departments.

Bismuth tungstate is a very important functional material in tungstate. It has been widely used in many fields, such as visible-light photocatalyst, water decomposition, hydrogen production, environmental purification and new energy development. It is well known that the properties of nanomaterials depend on the morphology and size of nanocrystals, so the preparation of bismuth tungstate nanocrystals with special morphology is of great significance in theoretical research and practical application.