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41.
Polarizing beam splitter has rather significant applications in polarization diversity circuits and polarization multiplexing systems. In this paper,we present an asymmetric polarizing beam splitter utilizing hybrid plasmonic waveguide. The special hybrid structure with a hybrid waveguide and a dielectric waveguide can limit the energy of TE and TM modes to a different layer. Therefore, we can achieve beam splitting by adjusting the corresponding parameters of the two waveguides. First, we studi... 相似文献
42.
The Fe/Mo multilayers were prepared by electron beam evaporation, the micro structure and magnetic properties of the multilayers were studied by X-ray diffraction, vibrating-sample magnetometer (VSM) et al. The experimental results revealed that the Fe/Mo multilayers in our experimental conditions behaved magnetoresistance effect with a sharp peak on magnetoresistance (MR) ratio curve, and magnetoresistance is easily saturated at low applied magnetic fields. For [Fe(1.5nm)/Mo(1.0nm)]4,2 multilayers, MR ratio could arrive to 0.1%. The antiferromagnetic interlayer coupling could be observed in some films at room temperature. The strength of the antiferromagnetic interlayer coupling J in the films is low because of the low saturation field Hs. The relationship between magnetic properties and micro structure was also discussed in this paper. 相似文献
43.
C.Leygraf J.Pan M.Femenia 《金属学报(英文版)》2004,17(5):625-631
Electrochem,cal scanning tunneling microscopy and scanning electrochemical microscopy have been used for in situ monitoring of localized corrosion processes of different Duplex stainless steels (DSS) in acidic chloride solutions. The techniques allow imaging of local dissolution events with micrometer resolution, as opposed to conventional electrochemical techniques, which only give an overall view of the corrosion behavior. In addition, combined scanning Kelvin probe force microscopy and magnetic force microscopy were used for mapping the Volta potential variation over the surface of DSSs. A significant difference in Volta potential between the austenite and ferrite phases suggests galvanic interaction between the phases. A compositional gradient appears within 2 micrometers across the phase boundary, as seen with scanning Auger microscopy (SAM). In all, the studies suggest that higher alloyed DSS exhibit a more homogeneous dissolution behavior than lower alloyed DSS, due to higher and more similar corrosion resistance of the two phases, and enhanced resistance of the ferrite/austenite phase boundary regions. 相似文献
44.
Members of tripartite motif (TRIM) proteins in mammals play important roles in multiple cellular processes in the immune system. In the present study we have obtained the chicken TRIM39 with the insertion of a base A at position 1006 bp, compared to the sequence in the NCBI database (Accession No: NM 001006196), which made TRIM39 fulfill the TRIM rule of domain composition with both PRY, and SPRY domains. The open reading frame consisted of 1392 bp encoding 463 amino acid residues. The amino acid sequences of TRIM39 protein in mammals were highly similar (from 91.48% to 99.61%), while chicken TRIM39 had relatively low homology with mammals (from 29.2% to 39.59%). Real time RT-PCR indicated that the mRNA expression level of TRIM39 was the highest in spleen, with a lower expression in liver, brain, and lung, suggesting it might be an important protein participating in the immune system. 相似文献
45.
46.
The production of ammonium paratungstate(APT) is riddled with the generation of wastewater,which causes environmental problems.To solve the problem of wastewater generation at source,a membrane electrolysis-NH3·H2O precipitation method,which prevents wastewater generation and recycles the reagents used in the process,was proposed and investigated in this study.The electrolysis process was investigated based on parameters such as initial cathodic and anodic NaOH concentratio... 相似文献
47.
Shuai-Hang Pan Gong-Cheng Yao Yi-Nan Cui Fan-Shi Meng Chuan Luo Tian-Qi Zheng Gurminder Singh 《钨科技(英文版)》2023,(1):1-31
Tungsten(W) materials are gaining more and more attention due to the extended applications of metallic systems in the extreme environments.Given W’s unique characteristics like room-temperature brittleness,additive manufacturing(AM)techniques could give them a higher design flexibility and manufacturability.With the growing focus and thriving development of W-faced AM techniques,since the mechanical performance of additively manufactured W parts is still unsatisfactory,a critical review to furth... 相似文献
48.
Yunyan Wu Pan Xiong Jianchun Wu Zengliang Huang Jingwen Sun Qinqin Liu Xiaonong Cheng Juan Yang Junwu Zhu Yazhou Zhou 《纳微快报(英文)》2021,(3):95-106
Graphitic carbon nitride(g-C3N4)-based photocatalysts have shown great potential in the splitting of water.However,the intrinsic drawbacks of g-C3N4,such as low surface area,poor diffusion,and charge separation efficiency,remain as the bottleneck to achieve highly efficient hydrogen evolution.Here,a hollow oxygen-incorporated g-C3N4 nanosheet(OCN)with an improved surface area of 148.5 m2 g^−1 is fabricated by the multiple thermal treatments under the N2/O2 atmosphere,wherein the C–O bonds are formed through two ways of physical adsorption and doping.The physical characterization and theoretical calculation indicate that the O-adsorption can promote the generation of defects,leading to the formation of hollow morphology,while the O-doping results in reduced band gap of g-C3N4.The optimized OCN shows an excellent photocatalytic hydrogen evolution activity of 3519.6μmol g^−1 h^−1 for~20 h,which is over four times higher than that of g-C3N4(850.1μmol g^−1 h^−1)and outperforms most of the reported g-C3N4 catalysts. 相似文献
49.
Shuai Yuan Changran Hu An Pan Yuedi Ding Xuanhao Wang Zhicheng Qu Junjie Wei Yuheng Liu Cheng Zeng† Jinsong Xia 《半导体学报》2021,42(4):43-52
Lithium niobate on insulator(LNOI)is rising as one of the most promising platforms for integrated photonics due to the high-index-contrast and excellent material properties of lithium niobate,such as wideband transparency from visible to mid-infrared,large electro-optic,piezoelectric,and second-order harmonic coefficients.The fast-developing micro-and nanostructuring techniques on LNOI have enabled various structure,devices,systems,and applications.In this contribution,we review the latest developments in this platform,including ultra-high speed electro-optic modulators,optical frequency combs,opto-electro-mechanical system on chip,second-harmonic generation in periodically poled LN waveguides,and efficient edge coupling for LNOI. 相似文献
50.
LEI Liping ZHAO Yinghong ZENG Pan Key Laboratory for Advanced Materials Processing Technology Beijing China Department of Mechanical Engineering Tsinghua University Beijing China 《机械工程学报(英文版)》2007,20(4):75-78
During plastic process,the material flow is strongly influenced by the contact area between deformed workpiece and die.In rolling process,difference of roll diameter makes the contact area between roll and deformed tape different,which leads to different material flow and the distribution of powder density.A numerical modelling of the first rolling process for 61-filament high temperature superconducting tape is constructed and the influences of roll diameters on deformation behavior of the tape are discussed.It can be found that the BiSrCaCuO(BSCCO)powder in the center of the tape has higher relative density than those in the periphery of the tape during rolling process.With the increase of roll diameter,the length of the contact arc in the roll gap expands which lead to the in- creasing of transversal strain and the decreasing of the related longitudinal strain.It makes the value of longitudinal strain ratio decrease gradually,which decreases the possibility of occurrence of the transversal shear band,simultaneously it increases the risk of occurrence of longitudinal crack. 相似文献