Radiotherapy (RT) is one of the most widely used methods to treat cancer in clinic. Its main principle is to inhibit the proliferation of cancer by using high intensity ionizing radiation (X-ray or gamma-ray) with very strong penetrating force.

Pearlescent pigments consist of metal oxide coated mica. Because of their excellent chemical corrosion resistance and high temperature resistance, pearlescent pigments have been widely used in building decoration, ink, automotive paint, textile printing and other fields. So far, the mature pearlescent pigments are titanium oxide (titanium dioxide) / tin oxide (SnO₂) / iron oxide (Fe₂O₃) - mica pearlescent pigments.

Nitrogen oxides (NO_x) are toxic and harmful gases that cause environmental problems such as acid rain and photochemical smog and pose a great threat to human beings. It is very important for human health to study high performance gas sensitive materials and devices for accurate detection and monitoring of nitrogen oxides.

Heteropoly acids with Keggin structure generally refer to inorganic compounds expressed in the following general chemical formulas. They are one of the most active catalysts used in acid catalytic reactions and redox reactions. It has good catalytic properties for the hydration and esterification of olefins, etherification of epoxides, alkylation of olefins and aldehydes, epoxidation of olefins and alkyl aromatization, etc. It has wide applications in petrochemical industry.

China's tungsten reserves are the first in the world, but with wolframite resources becoming scarce, the mining focus has gradually shifted to scheelite. How to develop efficient scheelite smelting process has become an important subject of tungsten metallurgy.

In 1993, the advent of LED brought a significant revolution in the field of lighting. Then in 1996, the first white LED solid light source was developed by using GaN-LED chip and YAG: Ce³⁺ phosphor to emit white light. Since then, white LED has surpassed incandescent lamp, fluorescent lamp and other lighting sources with the advantages of small size, low calorific value, low power consumption, long life, fast reaction speed, environmental protection and planar packaging.

With the rapid development of automotive industry, sulfur pollution caused by combustion of automotive fuels is becoming more and more serious. Strict sulfur content standards for gasoline and diesel have been formulated in various countries and regions of the world. Hydrodesulfurization (HDS) is usually used in industry to remove sulfides from gasoline and diesel.

Health is one of the most concerned topics. With the improvement of people's living standards, people's demand for antimicrobial materials and antimicrobial products will continue to increase.

With the rapid development of chemical industry, the variety and demand of ketals are increasing. Ketal is a kind of intermediate which can be used for carbonyl protection of organic compounds or pharmaceutical industry, even as a special reaction solvent. The synthesis of ketals is usually catalyzed by strong acid, which is synthesized by ketones and alcohols. The catalysts used are sulfuric acid, phosphoric acid, hydrogen chloride gas and p-toluene sulfonic acid. The advantage of the catalysts is that they are cheap and easy to obtain. However, the reaction easily produces wastewater which pollutes the environment and has strong corrosion effect on the equipment.

With the deepening of human exploration into space, more and more space vehicles are sent into space. NASA pointed out that the abnormal or failure of spacecraft due to lubrication failure has become an important factor affecting the effective service time of spacecraft. Therefore, how to maintain good lubrication of key components of spacecraft is a very important issue.