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81.
El-Saied Fathy A. El-Asmy Ahmed A. Kaminsky Werner West Douglas X. 《Transition Metal Chemistry》2003,28(8):954-960
CoII,III, NiII, and CuII complexes of new dehydroacetic acid N4-substituted thiosemicarbazones have been studied. The substituted thiosemicarbazones, N4-dimethyl-(DA4DM), N4-diethyl-(DA4DE), 3-piperidyl-(DApip) and 3-hexamethyleneiminyl-(DAhexim), when reacted with the metal chlorides, produced two CoII complexes, [Co(DA4DE)Cl2] and [Co(DAhexim)2Cl2]; two CoIII complexes, [Co(DA4DM-H)2Cl] and [Co(DApip-H)(DApip-2H)]; a paramagnetic NiII complex, [Ni(DAhexim)(DAhexim-H)Cl]; three diamagnetic NiII complexes, [Ni(DA4DM-H)Cl], [Ni(DA4DE-H)Cl] and [Ni(DApip-H)Cl]; and four CuII complexes with the analogous stoichiometry of the latter three NiII complexes. These new thiosemicarbazones have been characterized by their melting points, as well as i.r., electronic and 1H-n.m.r. spectra. The metal complexes have been characterized by i.r. and electronic spectra, and when possible, n.m.r. and e.s.r. spectra, as well as elemental analyses, molar conductivities, and magnetic susceptibilities. The crystal and molecular structure of the four-coordinate CuII complex, [Cu(DAhexim-H)Cl] has been determined by single crystal X-ray diffraction and the anionic ligand coordinates via an oxygen of the dehydroacetic acid and the thiosemicarbazone moiety's imine nitrogen and thione sulfur. 相似文献
82.
83.
Fabrication of Co/CoO Exchange Bias System by Ion Implantation and Its Magnetic Properties 下载免费PDF全文
We use ion implantation as a new approach to build an anti-ferromagnetic (AFM) cluster embedded exchange bias (EB) system. Co film with thickness of 130nm is deposited on the Si (111) substrate using magnetron sputtering, 60keV O+ is chosen to implanted into the Co film to form CoO AFM clusters coupling with Co matrix at the interface. By measuring the hysteresis loop after field-cooling, significant shifts of loop along the applied field are confirmed. When increasing the implantation dose to 2×1017/cm2 and annealed samples in N2 atmosphere, we obtain the highest HEB to 458Oe. 相似文献
85.
A novel and highly sensitive colorimetric sensor array was developed for the detection and identification of breath volatile organic compounds(VOCs) of patients with lung cancer.Employing dimeric metalloporphyrins,metallosalphen complexes,and chemically responsive dyes as the sensing elements,the developed sensor array of artificial nose shows a unique pattern of colorific changes upon its exposure to eight less-reactive VOCs and their mixture gas at a concentration of 735 nmol/L within 3 min.Potential of quantitative analysis of VOCs samples was proved.A good linear relationship of 490-3675 nmol/L was obtained for benzene vapor with a detection limit of 49 nmol/L(S/N=3).Data analysis was carried out by Hierarchical cluster analysis(HCA) and principal component analysis(PCA).Each category of breath VOCs clusters together in the PCA score plot.No errors in classification by HCA were observed in 45 trials.Additionaly,the colorimetric sensor array showed good reproducibility under the cyclic sensing experiments.These results demonstrate that the developed colorimetric artificial nose system is an excellent sensing platform for the identification and quantitative analysis of breath VOCs of patients with lung cancer. 相似文献
86.
以纳米碳酸钙为核体,用聚电解质对其表面改性后,采用均相共沉淀法制备了锡掺杂氧化铟(ITO)包覆的碳酸钙基浅色导电粉.通过改变聚电解质层数、ITO的包覆量及煅烧时间等实验条件,探究了制备纳米碳酸钙基浅色导电粉的最佳条件.用X-射线粉末衍射仪、扫描电子显微镜、X-射线电子能谱以及粉末电阻率测试仪等对样品的结构、形貌、化学组成及电阻率等进行分析.结果表明:聚电解质层数为5层,CaCO3与ITO的质量比为6∶1,500℃煅烧4.5h制备的粉末具有最佳的导电性能,其电阻率为3.8×103 Ω·cm. 相似文献
87.
88.
采用包埋技术制备了一种新型可光降解的聚氯乙烯-草酸-TiO_2(PVC-OA-TiO_2)纳米复合膜,并研究了紫外光照射条件下该复合膜的光催化降解情况.结果表明,该纳米复合膜的光催化降解是一个氧化断链过程,经紫外光照射310 h后失重率达到55%,是PVC-TiO_2复合膜的2倍,是纯PVC膜的3.5倍,说明草酸的掺杂可以促进PVC-OA-TiO_2复合膜更快地被光降解.草酸作为一个良好的电子给体,能不可逆地与TiO_2表面产生的空穴或表面羟基反应,抑制电子和空穴的复合,从而显著提高PVC-OA-TiO_2的光催化降解速率. 相似文献
89.
利用卟啉中位羧基基团直接缩合卟啉二聚体 总被引:2,自引:0,他引:2
卟啉单体的直接偶合法. 这种方法包括有β-β, meso-β直接连接的二聚体[8,9]和直接连接的N混杂的卟啉二聚体[10]. 我们利用二环己烷基羰化二亚胺(DCC)作催化剂, 在冰盐浴条件下, 通过两个5-(p-羧基苯基)-10,15,20-三苯基卟啉(H2CPTPP)周边上的羧酸基团一步直接缩合获得以羧酸酐连接的新型卟啉二聚体. 利用多种光谱手段证实所合成的物质为目标产物. 该方法具有反应物单一、 反应步骤简单、 副反应少、 产物纯化方便、 时间短和产率高等优点. 相似文献
90.