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排序方式: 共有93条查询结果,搜索用时 15 毫秒
1.
In this paper, we presented a novel method for the facile and efficient one-pot synthesis of 2-arylbenzoxazoles, which oxygen atmosphere with anhydrous tetrahydrofuran (THF) as solvent or in solvent-free condition. The results show that this method could bring excellent yields as high as 96%. THF was proven to be the best choice among several solvents screened and the reaction was tolerated with a variety of aromatic aldehydes possessing electron-donating or withdrawing groups. The advantages of the present method lie in catalytic process using economic and environmentally benign dioxygen as oxidant.  相似文献   
2.
Mg2Ni0.8Cr0.2-x wt.% CoO/Al2O3 (x=0.5, 1, 2 and 3) composites were prepared by mechanically milling sintered Mg2Ni0.8Cr0.2 alloy and CoO/Al2O3 compound for 45 h. The addition of CoO/Al2O3 compound resulted in the good kinetics properties of hydriding/dehydriding reaction of the composites. The composite with 1.0 wt.% CoO/Al2O3 catalyst could reach the maximum hydrogen absorption capacity (2.9 wt.%) within 5 min at 393 K under H2 pressure of 4 MPa, and can desorb rapidly at 493 K. The decomposition and synthesis of hydrogen molecule on Mg2Ni0.8Cr0.2 alloy surface was promoted by addition of CoO/Al2O3 catalyst. In addition, the formation of metallic Ni particles, strain and defects during the ball milling process also resulted in the improved hydrogenation performance of Mg2Ni-based alloys.  相似文献   
3.
INTRODUCTION With the development of industry, more and more pollutants are discharged into environment, among them, phenolic wastes are typical contami-nants considered to be hazardous and top priority toxic pollutants listed by the USEPA. They are toxic even at low concentration. Due to their biorefractory, bioaccumulation and carcinogenic potential, the treatment of these contaminants is very important in environmental protection. Various technologies and processes have been tried …  相似文献   
4.
介绍了新型精细化工产品过碳酸钠的性质、国内外生产现状、生产技术进展和应用情况.  相似文献   
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由于资源丰富,储氢容量较高,价格低廉,应用前景广阔等特点,镁基储氢合金材料成为近年来研究的热点,然而其稳定的热力学性和缓慢的动力学性限制了它的应用,因而对镁基储氢合金材料的改性日益成为了镁基储氢合金发展的重要方向,文章对镁基储氢合金材料的性能及改性方法进行了综述,并对其发展趋势进行了展望。  相似文献   
7.
In this paper, through the study of thermal conductivity of hydrogen- argon mixture at different temperatures for thermal insulation pipes in petroleum industry, a good method for determining the therm...  相似文献   
8.
本复方过氧化氢手消毒液,经多年的实验观察,其杀菌效果与5.00g/l的络合碘基本一致,并具有较好的稳定性,通过加入侵蚀剂和润肤、保温剂等组分,较好地解决了过氧化氢对皮肤具有较强刺激性的技术难题,从而为过氧化氢消毒制剂在皮肤消毒领域的应用提供了技术支持.为验证该消毒剂临床实际应用效果,以5.00g/l的络合碘作为对照进行了临床试验.通过对医务人员手卫生消毒和外科手消毒的比对试验结果观察.该复方过氧化氢手消毒效果与5.00g/l的络合碘消毒效果基本一致.  相似文献   
9.
对急冷凝固方法、熔融纺丝法、机械合金化法等制备Ti-Zr-Ni基准晶合金的方法进行探讨,综述了几种Ti-Zr-Ni基准晶合金的热力学和电化学贮氢性能。  相似文献   
10.
This study investigated the alleviating effects of hydrogen sulfide (H2S), derived from sodium hydrosulfide (NaHS), on inflammation induced by dextran sulfate sodium (DSS) in both in vivo and in vitro models. We found that NaHS injection markedly decreased rectal bleeding, diarrhea, and histological injury in DSS-challenged mice. NaHS (20 µmol/L) reversed DSS-induced inhibition in cell viability in Caco-2 cells and alleviated pro-inflammation cytokine expression in vivo and in vitro, indicating an anti-inflammatory function for H2S. It was also found that H2S may regulate cytokine expression by inhibiting the nuclear factor-κB (NF-κB) signaling pathway. In conclusion, our results demonstrated that H2S alleviated DSS-induced inflammation in vivo and in vitro and that the signal mechanism might be associated with the NF-κB signaling pathway.  相似文献   
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