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81.
一种铈(Ⅲ)配合物对含石墨粘结涂层耐蚀性的影响 总被引:1,自引:0,他引:1
为了改善含石墨粘结涂层的耐蚀性,首先对这种涂层在腐蚀环境中耐蚀性差的原因进行了分析,然后将二正丁基磷酸、CeF_3、Sb_2O_3和一种Ce(Ⅲ)配合物Ce(NO_3)(C_8H_(18)PO_4)_2分别添加于酚醛环氧-MoS_2-石墨粘结涂层中,考察了它们对这种涂层耐蚀性的影响,并对含Ce(NO_3)(C_8H_(18)PO_4)_2的涂层和空白样涂层进行了表面分析。盐雾试验表明,添加Ce(NO_3)(C_8H_(18)PO_4)_2可以有效地抑制涂层中MoS_2的氧化和由石墨所引起的金属底材之电化学腐蚀;根据X射线光电子能谱分析结果可知,添加Ce(NO_3)(C_8H_(18)PO_4)_2之所以能够提高含石墨粘结涂层的耐蚀性,应当归因于它在MoS_2晶体表面和金属底材表面的吸附。因此,Ce(Ⅲ)配合物Ce(NO_3)(C_8H_(18)PO_4)_2是含石墨粘结涂层的一种实用性能良好的新型防腐添加剂。 相似文献
82.
Fan Zhang Dang Wu Gao-Lei Wang Shuang Hou Ping Ou-Yang Jin Huang Xiao-Yong Xu 《中国化学快报》2017,28(5):1044-1048
A series of novel 1,2,3-benzotriazin-4-one derivatives were designed,synthesized and their inhibitory activities against leulcotriene A_4 hydrolase aminopeptidase in vitro were evaluated.Many compounds showed moderate to good activities at the concentration of 10 μmol/L.Among them,compound Ⅳ-16 exhibited the highest inhibitory activity up to 80.6% with an IC_(50) of 1.30 ± 0.20 μmol/L The compound Ⅳ-16 was also tested the proliferation inhibitory activities in THP1 human AML cell line and its binding model with LTA_4H enzyme by molecular docking was studied.It indicated that 1,2,3-benzotriazin-4-one was a promising scaffold for further study.The relationship between structure and inhibitory activity was also preliminarily discussed. 相似文献
83.
84.
Phu H. Dang Linh T. T. Nguyen Hue T. T. Nguyen Tho H. Le Truong N. V. Do Hai X. Nguyen 《Natural product research》2019,33(20):2883-2889
From an EtOAc-soluble fraction of the stem barks of Swintonia floribunda (Anacardiaceae), one new dimeric alkylresorcinol named integracin E (1), together with 4 known compounds (2–5) were isolated. Their chemical structures were elucidated based on the spectroscopic data interpretation. The absolute configuration of 1 was determined by the specific rotation analysis of its acid-catalyzed hydrolysis product. Compound 1 showed potent tyrosinase inhibitory activity with an IC50 value of 48.2?μM. 相似文献
85.
The chemical constituents of the fungus Verticillium psalliotae were studied. Two new aromadendrane sesquiterpenes inonotin M (1) and inonotin N (2) were isolated from the EtOAc extract of the fungal culture broth. The structures of compounds were elucidated mainly by HRESIMS experiments, and 1D, 2D-NMR spectroscopy analysis. 相似文献
86.
Qianxi Dang Lanzhen Hu Jiaqiang Wang Qunhua Zhang Mengmeng Han Simeng Luo Yanbin Gong Can Wang Prof. Qianqian Li Prof. Zhen Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(28):7031-7037
Organic luminescence with different forms continues to be one of the most active research fields in science and technology. Herein, an ultra-simple organic molecule (TPA-B), which exhibits both mechanoluminescence (ML) and photo-induced room-temperature phosphorescence (RTP) in the crystalline state, provides an opportunity to reveal the internal mechanism of ML and the dynamic process of photo-induced RTP in the same molecule. Through the detailed investigation of photophysical properties together with crystal structures, the key role of molecular packing and intermolecular interactions was highlighted in the luminescence response by mechanical and light stimulus, affording efficient strategies to design potential smart functional materials with multiple luminescence properties. 相似文献
87.
88.
Journal of Statistical Physics - In this paper, we will study the long time behavior of the simple symmetric exclusion process in the “channel” $$varLambda _N=[1,N]cap mathbb {N}$$... 相似文献
89.
Alignment carbon nanotubes (ACNTs) were synthesized on silicon substrate coated with Ni catalyst film and Ta buffer layer by plasma-enhanced hot filament chemical vapor deposition using CH4, NH3, and H2 as the reaction gas, and they were investigated by scanning electron microscopy and transmission electron microscopy. It is found that the diameter of the bamboo-structured ACNTs is increased from 62 to 177 nm when the substrate temperature was changed from 626 to 756 °C. Their growth rate is enhanced by the substrate temperature in a range of 626-683 °C and it is reversely reduced with the substrate temperature after the substrate temperature is over 683 °C. Beginning with wetting phenomenon, the effects of the substrate temperature on the structure and growth rate of the ACNTs are analyzed. 相似文献
90.
Effects of unsymmetrical geometric confinements on depletion interactions in colloidal suspensions 下载免费PDF全文
The depletion interactions between two large-spheres immersed in a fluid of small spheres under unsymmetrical geometrical confinement are studied through the acceptance ratio method. The numerical results show that no matter whether the volume fraction is large or small, both the depletion potential and depletion force are affected by the presence of the two plates; the closer the two large spheres are to the plate, the larger the effects of the unsymmetrical confinements. 相似文献