Tungsten Oxide

Ammonium Paratungstate (APT) is an important raw material product in tungsten smelting process, the appearance is white crystalline. It is mainly used for the reduction of tungsten oxide or ammonium metatungstate, and also used as catalysts or additives in chemical industry. The tungsten concentrate is screened and pressed, ammonium tungstate solution was prepared by ion exchange or extraction process, after the crystallization process, ammonium paratungstate was obtained. In the process of smelting, ammonium paratungstate solution (Na2WO4) was obtained from tungsten concentrate by ion exchange or extraction, in order to truly use ammonium paratungstate, an important process is needed: crystallization process. The crystallization process of ammonium paratungstate is one of the important processes in the tungsten smelting process, the crystallization methods of APT in industry mainly include evaporation crystallization method, neutralization crystallization method and freezing crystalli...

Photothermal therapy utilizes with high light heat conversion efficiency, inject it into the human body, target recognition technique is used to aggregate near the tumor tissue. The method of converting light energy into heat energy to kill cancer cells under the irradiation of external light source is a kind of cancer treatment method with great expectation by human beings. In the process of photothermal therapy, the selection of photothermal agents is a key link. These therapeutic agents can effectively convert laser energy into heat energy, thus enhancing the heating efficiency of laser. In order to achieve effective and selective photothermal therapy, photothermal agents must meet several conditions: It can absorb and transform laser energy effectively; A solvent that can be dissolved in a biologically friendly solvent, ensure that the treatment agent enters the tumor tissue smoothly; The surface of particles is easy to be functionalized, which is conducive to the cooperation with ...

The industrial production department has put forward more and more strict requirements on the performance of lubricating oil (grease). Ordinary equipment is often replaced by low-performance lubricants (grease) instead of high-performance products, causing equipment damage or lubricating oil (grease) consumption, therefore, it is of great significance to accelerate the research and development of high temperature lubricating oil (grease) to meet the needs of the domestic market. Tungsten sulfide is a compound of tungsten and sulfur, and it is a new kind of solid lubricant with excellent performance, not only suitable for general lubrication conditions, but also for high temperature, high pressure, high vacuum, high load, radiation and corrosive medium working environment, the magnetic properties of WS 2  clusters are not only lubricated but also adsorbed on the metal surface during lubrication. A layer of nano protective lubricating membrane is formed on the metal surface. Tungste...

Tungsten sulfide is an excellent solid lubricant material, it has high application value in the field of super solid lubrication, especially its role in the aerospace industry. Tungsten sulfide membrane have layered structure, it has lower hardness and better stability under high temperature, it is suitable to be used as a solid lubricant for friction parts in special environment. There are three main methods for preparing tungsten disulfide membrane which include RF sputtering method, reactive magnetron sputtering method, chemical deposition method. Reactive magnetron sputtering method is used to bombard pure tungsten targets with high energy noble gas and hydrogen sulfide mixed gas ions, the sputtered atoms react with the sulfur ions released from hydrogen sulfide gas to form a thin membrane on the substrate, reactive magnetron sputtering is also one of the most commonly used methods to obtain WS2 thin membranes. Preparation of WS 2  thin membranes on quartz substrates by reacti...

Tungsten carbide-based cemented carbide is widely used in cemented carbide, and high-quality tungsten carbide powder is the basis for preparing high-performance cemented carbide. What is the preparation method of high crystallinity tungsten carbide powder ? A preparation method of tungsten carbide powder with high carbonization crystal integrity and fast carbonization rate includes the following steps: 1) After mixing tungsten powder and carbon black, press the compact into a compact by a press; 2) Carburize the compact in step (1), after the carbonization is completed, ball milling and sieving can obtain high crystallinity tungsten carbide powder. Precautions for this preparation method: 1. In step (1), the F.S.S.S. particle size of the tungsten powder is 3-40μm, and the particle size of the tungsten powder is too fine and it is not easy to form during pressing. The pressing pressure of the press is 1.0-2.0mpa. The mixing is ball mill mixing, and the mixing time is 1~6h. 2. In step (2...

Spherical tungsten powder is used as a raw material in industries such as tungsten and tungsten alloy 3D printing, porous materials, and high-density powder spraying, and its preparation methods have attracted attention. So, what are the 6 preparation methods for spherical tungsten powder? The main domestic methods for preparing spherical tungsten powder are as follows: 1.Using the technology of secondary oxidation and reduction of tungsten powder, quasi-spherical tungsten powder can be obtained, and the manufacturing cost is low, but the spheroidization is not sufficient. 2. Using the granulation and sintering method to produce spherical powder for thermal spraying, spherical tungsten powder with a particle size of 40-750μm can be obtained. The density of the tungsten powder is not high, and the particle diameter is relatively large, and the powder is relatively coarse. 3. Use tungsten hexafluoride as raw material to prepare fine-particle (3～5μm) spherical tungsten powder. This method...

  Carbon neutral refers to the use of afforestation, energy saving and emission reduction to offset the carbon dioxide emissions generated by itself and achieve "zero emissions" of carbon dioxide. Carbon neutral is a solution proposed in response to global warming. Climate warming is the most concerned climate issue of humans all over the world today, and the core of climate warming is the increase in greenhouse gas carbon dioxide emissions caused by the increase in human activities. In response to this issue, from the 2009 United Nations Climate Change Conference in Copenhagen to the 2015 United Nations Climate Change Conference in Paris, all emphasis was placed on reducing carbon emissions. Up to now, the European Union, China, Japan, South Korea, etc. have all proposed carbon neutrality goals. The US President-elect Biden also proposed in his speech that the United States should return to the Paris Agreement. The basic requirement is the time when the United States should ...

Due to the intensification of the global greenhouse effect, extreme climate changes have been caused, resulting in a significant reduction in the area of arable land and making crops difficult to grow. Greenhouse cultivation can reduce the disasters caused by the climate to agricultural production, and maintain the stable production of crops, and solve the famine problems that may be faced in the future.  It is a gradual trend in crop planting methods. Due to the increasingly serious problem of oil shortage and global warming, the promotion of energy conservation and reduction of carbon dioxide emissions have become the goals of various governments. Among them, the promotion of energy-saving green buildings is a key project, so energy-saving greenhouses that can reduce energy use have also become a new development trend. The greenhouse shell shoulders the important functions of sheltering wind, rain, light regulation, heat insulation or heat preservation. The light-transmitting cov...