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91.
92.
The low-temperature synthesis of anatase TiO2 films was an imperative requirement for their application to corrosion prevention of metals. In this paper, a liquid phase deposition (LPD) technique was developed to prepare TiO2 films on SUS304 stainless steel (304SS) at a relatively low temperature (80 °C). The as-prepared films were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy and X-ray photon spectroscopy (XPS). It was observed that a dense and crack-free anatase TiO2 film with a thickness about 300 nm was obtained. The film contained some fluorine and nitrogen elements, and the amounts of these impurities were greatly decreased upon calcination. Under the white light illumination, the electrode potential of TiO2 coated 304SS rapidly shifted to a more negative direction. Moreover, the photopotential of TiO2/304SS electrode showed more negative values with increased film thickness. In conclusion, the photogenerated cathodic protection of 304SS was achieved by the low-temperature LPD-derived TiO2 film. 相似文献
93.
作为非齐次结合经典Yang-Baxter 方程的代数抽象,带权无穷小双代数在数学和数学物理领域扮演着重要的角色. 本文引入了带权无穷小Hopf模的概念,证明了带权拟三角无穷小单位双代数上的任意模都有一个自然的带权无穷小单位Hopf模结构.利用一种新的方式装饰平面根森林, 并证明根森林的空间,连同它上边的余乘和一组嫁接算子是集合上权为零的自由多重1-余圈无穷小单位双代数. 给出了余乘的一个组合解释.作为应用, 得到了未装饰的平面根森林上的余圈无穷小单位双代数范畴中的初始对象,它也是(非交换)Connes-Kreimer-Hopf代数中的研究对象. 最后,分别从任意带权无穷小双代数和带权交换无穷小双代数导出了两个预李代数,其中第二个构造推广了Novikov 代数上的Gelfand-Dorfman定理. 相似文献
94.
Hanane Bafqiren 《Tetrahedron》2010,66(34):7028-7034
Water mediates synthesis of novel hindered Schiff bases via transmination protocol. The feature of the procedure is that it allows both tuning of steric and electronic factors of the substituents and mono-imination of vicinal diamines, which potentially facilitates one-pot approach to unsymmetrical metal ligands. 相似文献
95.
D. Bradley G. Williams Sandile B. Simelane Michelle Lawton Henok H. Kinfe 《Tetrahedron》2010,66(25):4573-100
A simple and efficient method for the conversion of alcohols and phenols into their corresponding THP and THF ethers at room temperature has been developed using 1 mol % aluminium triflate as catalyst. The deprotection reaction in the presence of methanol using Al(OTf)3 was equally successful and could be performed at ambient temperature in high yields. 相似文献
96.
Shengjun Huang Jun Liao Qingjie Zhao Xiaoyun Chai Baogang Wang Shichong Yu 《Journal of carbohydrate chemistry》2013,32(2):158-168
TMSCl was shown to be an efficient reagent for selective deprotection of the anomeric position protected as N,O-dimethylhydroxylamine glycoside. This deprotection condition was proved to be compatible with a number of protecting groups, such as the TBDPS, acetyl, benzyl, benzylidene, and benzoyl groups. 相似文献
97.
2,2-Dimethyl- and 2-benzyl-2-methyl-1-(2,4,6-tri-tert-butylphenyl)-1-phosphaethenes were employed as ligand of mononuclear chlorogold(I) complexes, which catalyzed cycloisomerization of 1,6-enyne affording vinylcyclopentene exclusively in the absence of silver co-catalyst. The reaction mechanisms are discussed based on DFT calculations. In addition to the cycloisomerization, the phosphaalkene-chlorogold(I) complexes catalyzed cyclization of pent-4-ynoic acids providing γ-methylene-γ-lactones under basic conditions. 相似文献
98.
激光防护技术的发展现状 总被引:8,自引:1,他引:7
为了对抗日趋严重的激光致盲威胁 ,世界各国加速发展激光防护技术 ,并已取得了相当大的进展。本文综述激光防护技术的发展现状 相似文献
99.
Núñez-Regueira L. Rodríguez-Añón J. Proupín-Castiñeiras J. Romero-García A. 《Journal of Thermal Analysis and Calorimetry》2001,66(1):281-292
Calorific values and flammability changes during a year for forest waste originating from silviculture task in Galicia (NW
Spain) are reported. These waste materials are becoming to be used as alternative fuels.
The present study was made on several hardwood forest species. These forest species occupy nowadays approximately 30% of the
total forest surface of Galicia.
Calorific values were measured by static bomb calorimeter in an oxygen atmosphere. Flammability was determined using a standard
epiradiator. Simultaneously, some other parameters such as elementary chemical composition, heavy metal contents, moisture,
density, ash percentage after combustion in the bomb, and main bioclimatic characteristics, were also determined.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
100.
Rudolf Pietschnig 《Journal of fluorine chemistry》2007,128(2):150-152
The 29Si-19F INEPT NMR method has been applied to significantly reduce the recording time of 29Si NMR spectra of sterically shielded fluorosilanes. This technique furthermore improves the signal to noise ratio to a degree which allows the simultaneous detection of minor byproducts which are below the detection limit using direct acquisition. 相似文献