Calix[4]-crown-5-sulfonyl cyclothiourea derivatives 6 and 7 were synthesized from calix[4]-crown-5-monosulfonylethylenediamine derivatives 4 and 5 and carbon disulfide through nucleophilic addition and subsequent cycl...Calix[4]-crown-5-sulfonyl cyclothiourea derivatives 6 and 7 were synthesized from calix[4]-crown-5-monosulfonylethylenediamine derivatives 4 and 5 and carbon disulfide through nucleophilic addition and subsequent cyclization of intramolecule at room temperature in aqueous solution. The advantages of the novel protocol are the mild reaction condition, free organic solvent, simple final treatment, easy isolation of products and excellent yields.展开更多
As one of the countries that use the most concrete in the world, the development of concrete industry plays an important role in promoting the economic development of our country. Therefore, the actual operation of ea...As one of the countries that use the most concrete in the world, the development of concrete industry plays an important role in promoting the economic development of our country. Therefore, the actual operation of each concrete enterprise should be paid sufficient attention to. If the actual effect of concrete enterprises can be truly brought into full play, it will have an important impact on promoting the promotion of China's comprehensive national strength. But in the development process of concrete enterprises, they often have a great impact on the natural environment. Because the concrete enterprise is a very consumption of water resources industry. In the concrete pump pipe cleaning process, it will produce a large number of waste water waste residue, these waste water and waste residue will not only produce huge pollution to the surrounding residents of water resources, but also cause a great waste of water resources. At the same time, the production of a large number of industrial waste water will also have a bad effect on the development of concrete enterprises.展开更多
Major economies in the world have raised various proposals to reduce carbon emissions by applying clean energies in a bid to tackle climate change. As a major consumer of coal, China is facing mounting pressure, and e...Major economies in the world have raised various proposals to reduce carbon emissions by applying clean energies in a bid to tackle climate change. As a major consumer of coal, China is facing mounting pressure, and experts are wrangling about which clean energy should come first on the government agenda. To get a closer look at the current situation in China, Beijing Review reporter Liu Yunyun sat down with Zhou Dadi, Director General Emeritus of the Energy Research Institute of the National Development and Reform Commission, who shared his insights on clean energy. Edited excerpts follow:展开更多
基金Financial support from the National Natural Science Foundation of China(No.20802049) and Program for New Century Excellent Talents in University of Tianjin City
文摘Calix[4]-crown-5-sulfonyl cyclothiourea derivatives 6 and 7 were synthesized from calix[4]-crown-5-monosulfonylethylenediamine derivatives 4 and 5 and carbon disulfide through nucleophilic addition and subsequent cyclization of intramolecule at room temperature in aqueous solution. The advantages of the novel protocol are the mild reaction condition, free organic solvent, simple final treatment, easy isolation of products and excellent yields.
文摘As one of the countries that use the most concrete in the world, the development of concrete industry plays an important role in promoting the economic development of our country. Therefore, the actual operation of each concrete enterprise should be paid sufficient attention to. If the actual effect of concrete enterprises can be truly brought into full play, it will have an important impact on promoting the promotion of China's comprehensive national strength. But in the development process of concrete enterprises, they often have a great impact on the natural environment. Because the concrete enterprise is a very consumption of water resources industry. In the concrete pump pipe cleaning process, it will produce a large number of waste water waste residue, these waste water and waste residue will not only produce huge pollution to the surrounding residents of water resources, but also cause a great waste of water resources. At the same time, the production of a large number of industrial waste water will also have a bad effect on the development of concrete enterprises.
文摘Major economies in the world have raised various proposals to reduce carbon emissions by applying clean energies in a bid to tackle climate change. As a major consumer of coal, China is facing mounting pressure, and experts are wrangling about which clean energy should come first on the government agenda. To get a closer look at the current situation in China, Beijing Review reporter Liu Yunyun sat down with Zhou Dadi, Director General Emeritus of the Energy Research Institute of the National Development and Reform Commission, who shared his insights on clean energy. Edited excerpts follow:
