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141.
Electrodeposition of nanocrystalline zinc from acidic sulfate solutions containing thiourea and benzalacetone as additives 总被引:1,自引:0,他引:1
Mou Cheng Li Li Li Jiang Wen Qi Zhang Yu Hai Qian Su Zhen Luo Jia Nian Shen 《Journal of Solid State Electrochemistry》2007,11(4):549-553
Nanocrystalline zinc coatings were produced by pulse electrodeposition in acid sulfate bath containing thiourea and benzalacetone
additives and characterized by X-ray diffraction and scanning electron microscopy techniques. The influence of benzalacetone
concentration and pulse peak current density on the grain size and crystallographic orientation of zinc deposits was investigated.
Zinc electrodeposited from additive-free solutions or with one of the two additives is not composed of nanosized crystals.
The mixture additives of thiourea and benzalacetone give rise to the formation of particle-like nanocrystalline zinc with
a (10ī1) random orientation. A change in peak current density from 2 to 1 A/cm2 only increases the grain size from 60 to 62 nm. 相似文献
142.
Xuchu Ma Xuebing Li Yi Du Fen Xu Yitai Qian 《Journal of solid state chemistry》2004,177(10):3824-3829
The micro-sized Sb2O3 octahedra can be synthesized on a large scale via a simple PEG-1000 polymer-assisted hydrothermal route (PAHR) in the temperature range of 160-180 °C for 10-14 h. The structures, compositions, and morphologies of the as-synthesized products are derived from X-ray power diffraction pattern, X-ray photoelectron spectra, and field emission scanning electronic microscope. Meanwhile, the optical properties of the micro-sized Sb2O3 octahedra are studied by their photoluminescene spectroscopy and Raman spectrum. Furthermore, the possible growth mechanism of the micro-metered Sb2O3 octahedra is discussed on the basis of a series of supplementary experiments. And it has been found that PEG-1000, sodium tartrate, the reaction temperature, and the reaction time have considerable effects on the final morphology of Sb2O3, while the pH value has an influence on the formation of the Sb2O3 crystals. 相似文献
143.
文中采用机械合金化(MA)和氢化燃烧法(HCS)制备了Mg1.9Al0.1Ni,通过对它们储氢性能的对比研究发现,MA优于HCS.采用MA制得的Mg1.9Al0.1Ni储氢合金具有较高的活性和高储氢量,对PCT结果进行计算,得出温度和氢平衡压的关系式.Mg1.9Al0.1Ni(MA)553K时100s内吸放氢量分别为2.67和2.54 mass%H.用XRD方法进行物相分析,表明添加适量Al没有改变Mg2Ni的物相结构,由于MA能够制备出纳米晶粒,使得Mg1.9Al0.1Ni合金具有更好的储放氢动力学性能. 相似文献
144.
The gold nanoprisms (GNPs) have exhibited special plasmonic properties for biomedical applications because of their unique shapes and dimensions. Based on their optical performance, the NIR dye IR780 not only enabled the GNPs-based nanosystem as SERRS nanoparticles for Raman-encoded molecular imaging, but also enhanced the plasmonic photothermal property by laser irradiation. Meanwhile, the GNPs/IR780-Lyp-1 by introduction of tumor-homing peptide segment LyP-1, which presents high affinity to p32 protein, demonstrated the increased enrichment in tumor region and enhanced photothermal therapy efficacy. 相似文献
145.
用循环伏安法研究了分子沉积(MD)膜的屏蔽效应,讨论了不同条件对其成膜性和稳定性的影响,得到了金电极表面沉积规整MD膜的一般机制和佳成膜条件,证实了MD膜的自发有序排列的组装过程。 相似文献
146.
Zhi-Chu Bi Yue-Ying Qian Xin-Li Zhao Shu-Yin Shen Jia-Yong Yu Hui-Jun XU H. Ti Tien 《Photochemistry and photobiology》1994,59(1):111-115
Abstract Zinc phthalolocyanine photosensitized donor-acceptor systems for light energy conversion and for the design of photoelectrochemical molecular devices are presented. Covalently linked phthalocyanine complexes were incorporated in bilayer lipid membranes (BLM) and deposited on SnO2 transparent electrodes. Their photovoltages were measured and compared. It has been found that a more favorable orientation and closer proximity are attained in the diad compounds between the donor (phthalocyanine)-acceptor (anthraquinone) pair than in the reference compound for efficient light-induced charge separation and transfer. The triad compound is the best among all tested compounds. The decrease in the fluorescence yield and lifetime induced by quinones was examined and the apparent electron-transfer rate constants were calculated. 相似文献
147.
郭黎平 《高等学校化学学报》1993,14(1):29-32
本文将自制Y式玻碳电极拉上两性接枝星形聚合物(GPSMA)的LB膜,用循环伏安法研究谈膜的屏蔽效应,讨论了接枝量、成膜条件等对膜缺陷的影响,并提出了减少缺陷的办法。 相似文献
148.
FANG Fang ZHU Yu ZHAO Qian JIANG Gang WANG Hong-Yan 《结构化学》2007,26(9):1092-1096
Geometric and electronic properties of Pdn–1Pb and Pdn (n≤8) clusters have been studied by using density functional theory with effective core potentials, focusing on the differences between mono- and bimetallic clusters. The average bond length of Pdn–1Pb (n≤8) bimetallic clusters is longer than that of pure palladium clusters except for n = 2 and 3. The most stable structure of Pdn–1Pb (n≤7) is the singlet where there is at least a Pd or Pb atom on its excited state. The energy gaps of Pd–Pb binary clusters are narrower than those of Pdn clusters, and then the chemical activity is strengthened when Pdn clusters are doped with Pb. 相似文献
149.
Chun-Yang Jina Dao-Dao Zhang Tetsuya Oguma Shi-Xiong Qian 《Journal of inclusion phenomena and macrocyclic chemistry》1996,24(4):301-310
Cycloisomalto-heptaose (CI-7) and cycloisomalto-octaose (CI-8) are two novel cyclodextrans. Treatment with C60 or C70 by kneading leads to the formation of four distinct water-soluble inclusion complexes: CI-7/C60 (2: 1), CI-8/C60 (2: 1), CI-7/C70 (2: 1) and CI-8/C70 (2: 1). Their formation and structures have been examined by UV vis spectroscopy, X-ray powder diffraction and fluorescence spectral studies. The reaction is a reversible process. 相似文献
150.
2,5—二取代—1,3—4—恶二唑和N,N‘—二酰基肼化合物的合成与生物活性 总被引:2,自引:0,他引:2
合成了18种新的对称与不对称的2,5-二取代-1,3,4-恶二唑及N,N“'-F二酰基肼化物,用元素分析,红外光谱,核磁氢谱和质谱确定了其结构,并对它们的杀虫,抗菌活性进行了测试,发现了数个具有较强生物活性的化合物。 相似文献