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1.
Poly-N,N-dimethylaniline was prepared by electrochemical polymerization of the monomer on gold, platinum and tin oxide electrodes in an acid medium. The polymer was characterized by cyclic voltammetry and scanning electron microscopy. Poly-N,N-dimethylaniline electrodes, modified by electrodeposition of palladium particles, were prepared.  相似文献   

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New starburst ethoxy naphthylamine is synthesized using multi-step organic reactions. The synthesized compound is characterized using UV-Visible, FT?CIR and NMR spectrometric techniques. The thermal and electrochemical property of the compound was studied using DSC and cyclic voltammetry. Using this compound and a natural dye, organic dye sensitized solid state solar cell was fabricated and the performance analysed.  相似文献   

4.
Nécrologie     
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15N/14N isotope ratios are widely used to study processes and systems involving amino acids. Nitrogen isotope fractionation in biological processes occurs primarily at sites of bond-breaking and formation; the finest discrimination for "isotopic fingerprinting" and studies of isotopic fluxes is thus obtained at the position-specific level. While there are numerous reports of natural intramolecular carbon isotope variability, there are no literature reports of 15N/14N position-specific isotopic analysis (N-PSIA) of biologically relevant molecules. We report a methodology for high-precision N-PSIA of four polynitrogenous alpha-amino acids (asparagine, glutamine, lysine, histidine) and the first survey of natural intramolecular 15N/14N in these biomolecules. Selective liberation of N-atoms from multiple commercial standards of each parent amino acid was achieved by an appropriate enzymatic reaction or by acid hydrolysis. 15N/14N measurements were performed on N-ethoxycarbonyl ethyl ester derivatives of the parent amino acids and their analogues by gas chromatography combustion isotope ratio mass spectrometry, and the average precision for replicate injections was found to be SD(delta15N) = 0.3%. Position-specific delta15N values of the parent amino acid were directly observed or indirectly calculated using mass balance. The average precision obtained for directly measured positions was SD(delta15N) = 0.2-0.4%. The average precision for indirectly obtained positions was SD(delta15N) = 0.6-1.3% as a result of propagation of errors. Enrichment in the side chain-N with respect to the peptide-N was observed in nearly all of the amino acid sources, most notably in asparagine (average delta delta(side-peptide) = + 11%), which may be indicative of its method of production. In some cases, it was possible to distinguish commercial sources by N-PSIA that could not be distinguished at the compound-specific level.  相似文献   

8.
以金刚烷胺为原料,通过艾希魏勒-克拉克反应(Eschweiler-Clarke)合成了N,N-二甲基金刚烷胺,优化反应条件为金刚烷胺∶甲酸∶甲醛的摩尔比为1∶5∶4,反应时间为18h,温度为98℃,产物收率93.4%,进而合成了N,N,N-三甲基-1-金刚烷基季铵盐,产物收率90.5%,其结构经1H-NMR,13C NMR,MS和GC-MS表征。  相似文献   

9.
二苯甲烷双马来酰亚胺的合成和性能   总被引:11,自引:0,他引:11  
采用3种方法合成了二苯甲烷双马来酰亚胺(BDM),用IR、DSC、SEM和凝胶化时间等方法表征和分析了各法合成BDM及其副产物(BPC)的结构和性能,探讨了BPC的影响。研究认为,BPC能抑制BDM的聚合和活性,对BDM性能不利,文中探索了合成BDM时减少BPC含的若干途径。  相似文献   

10.
以可溶性淀粉为原料,用反相悬浮法合成了N,N'-亚甲基双丙烯酰胺交联淀粉微球ASM.最佳合成条件是可溶性淀粉2g,N,N'-亚甲基双丙烯酰胺0.2g,K2S2P8 0.04g,W/O相体积比1∶3,反应时间2h,反应温度50℃.ASM外型规则,粒度10~20 μm.探讨了成球机理,提出了交联反应主要在淀粉分子结构外围进行的推论并获得了实验支持.在25℃,ASM对Cu2 、Cr3 、Cd2 、Pb2 的饱和吸附量分别是2.75、2.20、0.88、0.77 mmol·g.HCl、ZnCl2使ASM对Cu2 的吸附量明显降低,MgCl2使吸附量略有降低.ASM的空间网状结构使金属离子容易深入其内部形成多点配位,配位吸附是ASM吸附金属离子的主要作用形式.  相似文献   

11.
Fe_3N和Fe_4N粉状化合物的合成及其电磁特性研究   总被引:1,自引:0,他引:1  
纯铁粉在氨和氢的气氛中进行固气反应合成Fe3N和Fe4N粉状化合物。研究了氨气和氢气比例、温度以及时间对固气反应产物的影响,进而分别获得纯相粉状Fe3N和Fe4N化合物。利用矢量网络分析仪测试了Fe3N和Fe4N的磁导率和介电常数,并与市售铁氧体进行了比较。发现在1MHz~1GHz频段内,Fe3N和Fe4N的磁导率低于铁氧体,介电常数均高于铁氧体,且Fe4N的电磁性能优于Fe3N。  相似文献   

12.
Micromachining based on metallic structural material possesses several inherent advantages. Metallic thin films can be deposited at room temperature by various means. In microelectromechanical systems they can thus be fabricated on top of polymeric sacrificial materials. The sacrificial layer is finally removed in oxygen plasma either before or after wafer dicing with no need for wet processing. However, in metallic micromachining, it is not trivial to find materials and processes producing structural layers with well‐controlled and uniform mechanical characteristics. Amorphous alloys Mo–N and Mo–Si–N are investigated in this study for the purpose, showing properties superior to polycrystalline metals for microelectromechanical devices and systems applications.  相似文献   

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14.
N. A. Shost'in     
《Measurement Techniques》1971,14(4):664-664
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15.
橡胶硫化剂N,N'-间苯撑双马来酰亚胺的合成   总被引:1,自引:0,他引:1  
研究了以乙酸做溶剂,以马来酸酐和间苯二胺为主要原料合成间苯撑双马来酰亚胺的合成方法;通过正交试验,找出了反应的优化条件;通过熔点仪、红外光谱仪、高效液相色谱仪对合成产品进行定性和定量分析.结果表明:溶剂乙酸的用量为间苯二胺质量的3倍,反应容易操作进行;催化剂与间苯二胺的摩尔比为0.05~0.3;马来酸酐与间苯二胺的摩尔比为2.1/1,在此优化条件下产物的得率为90.2%;红外光谱图与标准图谱一致,合成产物的含量为96%.  相似文献   

16.
聚合型半导体材料g-C3N4因其优异的物理性能和光电性能成为当今研究的热门材料。本文从结构分析和理论计算角度讨论了g-C3N4能够作为无金属催化剂的原因,综述了介孔g-C3N4、无机元素掺杂g-C3N4、金属负载g-C3N4、g-C3N4/金属氧化物复合物和有机改性g-C3N4等不同改性g-C3N4的制备和性质,着重分析了他们催化光解水析氢反应的机理、影响因素及研究进展,并阐述了今后的研究方向。  相似文献   

17.
Abstract

We study the effect of the addition of a cross-linking agent (N,N′-methylenebisacrylamide) to a photopolymerizable matrix for real-time holography. Optimization of the concentration of this component has been achieved, paying attention to holographic parameters such as energy sensitivity and diffraction efficiency. Diffraction efficiencies of around 88% have been obtained with energy exposures of 12 mJ cm?2. At the same time considering a nonlinear response of the material we have carried out a theoretical study of the experimental results. We observed a nonlinear response of the material with regard to the storage intensity. This is a very interesting point in reflection holographic optical elements.  相似文献   

18.
The ground-state properties of helium clusters 4He N and 4He N 3He, for N≤ 40, adsorbed on the surface of cesium are studied using variational and diffusion Monte Carlo calculations. Binding properties are determined using two different Cs–He interaction potentials. For the smallest clusters, self-binding on a Cs surface is stronger than in two or three dimensions. For N > 10 self-binding in three dimensions is stronger than on Cs for both types of Cs–He interaction potential considered. The obtained binding energies and structure are compared to results of recent density functional calculations. The emergence of edge states of 3He atom, localized along the contact line of 4He cluster with a cesium surface, is studied. First indication that 3He atom prefers to be close to the contact line appears already for the 4He3 3He cluster.  相似文献   

19.
N. I. Tyurin     
《Measurement Techniques》1971,14(4):665-665
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20.
N. F. Rymar'     
《Measurement Techniques》1960,3(3):264-264
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