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861.
Inthecourseofourscreeningnewantifungalandanticancercompoundsusingthebioassaysystembasedonmorphologicaldeformationorgrowthinhibiti0n0fPyriculariaoryzae,anovelactivecomPoundWAwasobtainedfromthemetab0litesofthefungusstrain38isolatedfromasoilsample'.ItSminimalinhibitionc0ncentrationwas288.4pglml.InthispaPer,wedescribethephysic0-chemicalpr0pertiesandstructureelucidationofWA.Comp0undWAwasobtainedaswhitep0wderhavingmeltingpointl2ful28"C.Itsm0lecularformula,Cl1HIo04,wasdeterminedbyCI-MS[Inlz20… 相似文献
862.
863.
Cheng JK Yao YG Zhang J Li ZJ Cai ZW Zhang XY Chen ZN Chen YB Kang Y Qin YY Wen YH 《Journal of the American Chemical Society》2004,126(25):7796-7797
A simultaneous redox, alkylation, self-assembly reaction under solvothermal conditions afforded a novel copper(I) chain polymer constructed of luminescent Cu3I4- and unprecedented EtS-4-C5H4N+Et components (Et = CH3CH2). 相似文献
864.
The electrostatic potentials and fields created by the thiol protease, papain, are computed on the surface envelope of the protein and in the region of its active site using a technique based on accurate multipole expansions of the electron density of appropriately chosen subunits. The effect of binding counterions to the protein is considered specifically. The possible role of the “electrostatic environment” in the functioning of the enzyme is discussed and it is found that this environment can favor the proton transfer between Cys 25 and His 159 that is thought to initiate its mode of action, but that the reasons for this appear more complicated than earlier models would suggest. 相似文献
865.
866.
与单纯的磁光晶体相比,由磁光介质与电介质周期性或准周期性排列构成的一维磁光光子晶 体能够显著增强磁光效应,可以用于实现小尺度的磁光隔离器,从而大大减小器件的尺寸. 给出更为一般的可用于求解斜入射情况下偏振光在各向异性介质中传播时的传输矩阵方法, 并用这种方法在波长为1053μm处,针对两种“三明治”型的反射磁光多层膜隔离器的 结构,具体讨论了器件应用时入射角度及工艺制作时膜层制备厚度对它们工作稳定性的影响 .发现中心磁光介质夹层较厚的结构具有膜层数目少、工作稳定性好的优点.
关键词:
光隔离器
磁光效应
一维光子晶体 相似文献
867.
2,6-Bis[4-(p-dihexylaminostyryl)styryl]anthracene derivatives with large two-photon cross sections 总被引:1,自引:0,他引:1
[Structure: see text] Anthracene derivatives with a variety of donor-acceptor substituents have been synthesized and shown to exhibit large two-photon cross sections over a wide range of wavelengths. 相似文献
868.
A high-throughput experimental methodology was developed for photocatalysis reaction. In this work, a CCD imaging analysis system and photocatalytic reactor for UV light was designed and tested. By making use of the technologies, we have screened several catalyst libraries. From the SiO2-supported single component catalyst library, we found that TiO2, ZrO2, Nb2O5, and WO3 were good candidates for highly active catalyst formulation. We designed and screened several triangle catalyst libraries and found that the WO3- and Nb2O5-codoped TiO2 catalyst showed much higher photodegradation activities for the degradation of 1,6-hexamethylenediamine than did the pure TiO2 catalyst. The doping of ZrO2 into TiO2 did not generate apparent positive effects on catalytic activity. 相似文献
869.
We report on the successful synthesis of silver sulfide (Ag(2)S) nanowires by a simple and mild gas-solid reaction approach. For the nanowire synthesis, a preoxidized silver substrate is exposed to an atmosphere of an O(2)/H(2)S mixture at room temperature or slightly above. The resulting Ag(2)S nanowires are phase pure with a monoclinic crystal structure and have diameters of a few tens of nanometers and lengths up to 100 mum. The influence of reaction conditions on the diameter, length, and morphology of the Ag(2)S nanowires has been studied by a number of structural and spectroscopic techniques. The nanowire growth mechanism on the Ag substrate has been discussed, which is likely characterized by continuous deposition at the tip. Additionally, we demonstrate thinning and cutting of individual Ag(2)S nanowires with electron beams and laser beams, which are potentially useful for nanowire manipulation and engineering. 相似文献
870.
Ultralong single-crystalline TiO(2) nanowires were prepared by a simple, low-cost solvothermal process. Silver nitrate, neodymium chloride, ceric nitrate, stannic chloride hydrate, and cadmium chloride were used as metal sources and deposited by reduction on the surface of TiO(2) nanowires. The composites were subsequently characterized by transmission electron microscopy, and their coverage was compared. The nature of the coatings on the TiO(2) nanowires varies from metal to metal. A novel approach on modified one-dimensional nanostructures with metal coating was developed, which has great potential applications in catalysts, sensors, and nanoscale devices. 相似文献