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81.
Uwe Herzog Uwe Böhme Gerd Rheinwald 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):281-286
The reactions of Me2MCl2 (M = Si, Ge, Sn), Si2Me4Cl2, Si2Me2Cl3, Si2Me2Cl4 and CH2(SiCl2Me)2, and suitable mixtures thereof, with H2S / NEt3 and Li2E (E = Se, Te) have been investigated and lead to a variety of new group 14 chalcogenide systems. 相似文献
82.
H. R. Prakash Naik H. S. Bhojya Naik T. R. Ravikumar Naik M. Raghavendra T. Aravinda D. S. Lamani 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):460-470
The synthesis of quinoline-substituted phenylquinazolinones containing sulfur and selenium is described. These molecules were isolated from a series of reactions of 2-phenyl-4H-3,1-benzoxazin-4-one with 2-chloro, 2-thieno, and 2-selenoquinoline-3-carbaldehyde hydrazones. The structure of the isolated compounds has been elucidated on the basis of IR, 1 H NMR, mass spectral, and elemental analysis data. 相似文献
83.
Michio Iwaoka Shuji Tomoda 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):755-766
Weak nonbonded interaction between a divalent selenium and an oxygen atom (i.e., Se···O interaction) frequently plays important roles in chemical and biological functions of selenium compounds. To establish that 77 Se NMR is an easy experimental probe to diagnose the strength of an Se···O interaction, 3 series of 2-substituted benzeneselenenyl derivatives, which have an intramolecular Se···O interaction in solution, were employed. By comparing the 77 Se NMR chemical shifts (δ Se ) with those observed for other series of selenium compounds, which have an intramolecular Se···Y (Y = N, O, F, Cl, or Br) interaction, approximate linear correlation was found between the δ Se values and the strengths of the nonbonded Se···Y interactions evaluated by natural bond orbital analysis at the B3LYP level. The correlation will be useful for estimating the strength of an Se···O interaction simply from the 77 Se NMR chemical shift. By extending the chemistry of nonbonded Se···O interactions to structural biology, analogous S···O interactions have been discovered in protein architecture. The directional features were, however, different from those of Se···O and S···O interactions of small organic compounds. 相似文献
84.
Stephen Brand John Milton Martin F. Jones Christopher M. Rayner 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):367-368
A new method for the synthesis of cyclic and acyclic optically active S,O-acetals is reported, along with subsequent stereocontrolled transformations, culminating in a synthesis of the important antiviral nucleoside Lamivudine. 相似文献
85.
One‐dimensional fullerene nanostructures with well‐defined morphology have been prepared by a controllable method. Fullerene molecules, such as C60 derivatives and endohedral metallofullerenes, are introduced into the pores of anodic aluminum oxide (AAO) templates under a direct current (DC) electric field. Then several nanostructures such as porous‐wall and solid‐wall fullerene nanowires and nanotubes were fabricated in the pores. The morphology of the fullerene nanostructures is well controllable, and the fullerene nanotubes can be further fabricated through filling nickel atoms inside to form fullerene‐metal composite structures. The results provide, in principle, a step toward broader applications of fullerene‐related materials in nanoscience and nanotechnology. 相似文献
86.
This paper is an up-to-date mini-review based on literature data and own results regarding synthesis and properties of conducting (pseudo)rotaxane supramolecular structures. Conjugated polymers, such as polyarylene, polyheteroarylene, polyaniline, polyarylenevinylene or polyaryleneimine, were used as axle, while the macrocyclic components were cyclodextrins, cucurbiturils, cyclophanes or crown ethers. Properties of the supramolecular structure such as solubility, thermal or chemical stability, conductivity, etc. can be drastically modified by the inclusion of hydrophobic conjugated polymers inside the macrocycle, without any chemical modification. For instance, the photophysical properties (i.e. quantum yield of fluorescence and electroluminescence) of the supramolecular structures were enhanced when compared with uninsulated conjugated polymers. The doping process is also affected, because the access of a dopant to the conjugated chain is limited only to the uncovered domains of the conjugated chain. 相似文献
87.
In this work, we develop a low‐temperature, facile solution reaction route for the fabrication of quantum‐dot‐sensitized solar cells (QDSSCs) containing Ag2S‐ZnO nanowires (NWs), simultaneously ensuring low manufacturing costs and environmental safety. For comparison, a CdS‐ZnO NW photoanode was also prepared using the layer‐by‐layer growth method. Ultraviolet photoelectron spectroscopy analysis revealed type‐II band alignments for the band structures of both photoanodes which facilitate electron transfer/collection. Compared to CdS‐ZnO QDSSCs, Ag2S‐ZnO QDSSCs exhibit a considerably higher short‐circuit current density (Jsc) and a strongly enhanced light‐harvesting efficiency, but lower open‐circuit voltages (Voc), resulting in almost the same power‐conversion efficiency of 1.2 %. Through this work, we demonstrate Ag2S as an efficient quantum‐dot‐sensitizing material that has the potential to replace Cd‐based sensitizers for eco‐friendly applications. 相似文献
88.
采用纳米SiO2和酚醛树脂为原料制备酚醛树脂裂解碳纳米SiO2复合阴极(硅碳物质的量的比为1:1),直接电解PFC/SiO2复合阴极,在900℃熔融盐CaCl2中,恒槽压2.0V下电解,制备出碳化硅纳米线。采用场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)、高分辨透射电子显微镜(HRTEM)及其附带的能谱仪、X射线分析衍射仪(XRD)和拉曼光谱(Raman)对产物的组成、形貌、微观结构等进行了表征。结果表明:碳化硅纳米线呈立方晶体结构,其直径为4~13nm,长可达数微米;室温下该纳米线在415nm和534nm附近有宽的发光峰。最后,讨论了碳化硅纳米线的生成机制。 相似文献
89.
目的:测定白砂糖和红糖中硒含量为研制富硒糖提供科学依据。方法采用微波消解-原子荧光光谱法测定白砂糖和红糖中硒含量。结果在确定的最佳仪器条件下,原子荧光光谱法测定白砂糖和红糖中硒的检出限为0.063μg · L-1;白砂糖硒的RSD为2.28%,红糖的RSD为2.13%;白砂糖回收率为103.4%,红糖回收率为99.7%。结论该法具有方法简便、快捷、准确等优点,适用于白砂糖和红糖中硒含量测定。 相似文献
90.
《Green Chemistry Letters and Reviews》2013,6(4):420-434
ABSTRACTBiogenic synthesis of bimetallic nanoparticles (gold – AuNp and selenium – SeNp) using inexpensive Tryptophan Enriched Banana Peel Media for the growth of marine isolate (Exiguobacterium aestuarii SBG4 MH185868). The response surface methodology is employed for optimizing production conditions. The surface plasmon resonance band showed λmax at 540?nm (AuNp) and 284?nm (SeNp). FTIR and zeta potential analysis confirmed the stability, whereas XRD spectra revealed the nature of nanoparticles obtained at optimum conditions. SEM micrographs showed nanospheres of the following size: AuN, 30?±?5 nm and SeNp, 50?±?5 nm. Biocompatibility of Np evaluated by the hemolytic activity showed <20% hemolysis even at highest concentrations (100?µg/ml). AuNp showed the least cytotoxicity, whereas SeNp showed considerable cytotoxicity against the breast cancer cell lines MCF – 7 and MDA-MB-231. Hence, we utilized the environment-friendly growth media for the controlled synthesis of dual Np using single bacterial strain involving feasible steps in downstream processing. 相似文献