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Fabrication of 3D biomimetic composite coating with broadband antireflection, superhydrophilicity, and double p-n heterojunctions

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Nano Research 2017年第7期10卷 2377-2385页

作者： gang Shi Xin Zhang Jianhua Li Haiyan Zhu Ying Li Liping Zhang Caihua Ni Lifeng chi The Key Laboratory of Food Colloids and Biotechnology Ministry of Education School of Chemical and Material Engineering Jiangnan University Wuxi 214122 China National Engineering Laboratory for Cereal Fermentation Technology Jiangnan University Wuxi 214122 China Institute of Functional Nano and Soft Materials (FUNSOM) Soochow University Suzhou 215123 China Physikalisches Institut and Center for Nanotechnology (CeNTech) Westfalische Wilhelms-Universitat Munster Munster D-48149 Germany

The traditional single material with two-dimensional （2D） biomimetic moth-eye structures is limited by its narrowband antireflection and single functional capability. To overcome these disadvantages, we exploited wet etching and hydrothermal synthesis coupled with chemical oxidation for fabricating a three- dimensional （3D） biomimetic moth-eye coating with ternary materials （polypyrrole nanoparticles, TiO2 nanorods, and Si micropyramids, i.e., PPy/TiOa/Si-p）. This coating reduced the reflectivity to 〈4% at wavelengths ranging from 200 to 2,300 nm and exhibited remarkable superhydrophilidty with a low water contact angle of 1.8°. Moreover, the composite coating had double p-n heterojunctions, allowing the high-efficiency separation of photogenerated carriers. The photo- current density of PPy/TiO2/Si-p was more than three times higher than that of TiO2/Si-p at a positive potential of 1.5 V. The proposed method provides a means to enhance solar energy conversion.

关键词： biomimetic compositecoating broadband antireflection superhydrophilicity double p-n heterojunctions

Crystallographic analysis of lath martensite in a 13Cr-5Ni steel by electron backscattering diffraction

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Journal of Iron and Steel Research International 2018年第2期25卷 213-220页

作者： Wen-bo Liu Peng-cheng Song chi Zhang Di Yun Chun-fa Yao Zhi-gang Yang Department of Nuclear Science and Technology Xi' anJiaotong University Xi'an 710049 Shaanxi China china Science and Technology on Reactor Fueland Materials Laboratory Nuclear Power Institute of ChinaChengdu 610213 Sichuan China Key Laboratory of Advanced Materials of Ministryof Education School of Materials Science and EngineeringCollaborative Innovation Center of Advanced NuclearEnergy Technology Tsinghua University Beijing 100084China Central Iron and Steel Research Institute Beijing 100081China

Morphology observation and crystallographic analysis of lath martensite in 13Cr-5Ni steel were investigated by electron backscattering diffraction （EBSD） in a scanning electron microscope. The pole figures of the microstructure measured by EBSD showed that the martensite in this steel held the Kurdjumov-Sachs （K-S） orientation relationship, and the boundary misorientations after the austenite-martensite transformation were also analyzed. However, not all the 24 possible variants in the K-S relationship were observed in a single prior austenite grain. Sub-blocks with special combinations were observed, which can be explained by the minimization of the total shape strain between the adjacent variants introduced during the martensite transformation and relatively low carbon content in the 13Cr-5Ni steel.

关键词： Electron backscattering diffraction Martensite transformation Boundary misorientation Orientationrelationship

Glass-forming ability, microhardness, corrosion resistance, and dealloying treatment of ***40Ndx alloy ribbons

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International Journal of Minerals,Metallurgy and Materials 2017年第6期24卷 708-717页

作者： Hao-yi chi Zhen-gui Yuan Yan Wang Min Zuo De-gang Zhao Hao-ran Geng Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials School of Materials Science and Engineering University of Jinan Jinan 250022 China

The influence of Nd addition on the glass-forming ability (GFA), microhardness, and corrosion resistance of Mg60−xCu40Ndx(x = 5, 10, 15, 20, and 25, at%) alloys were investigated by differential scanning calorimetry, Vickers-type hardness tests, and electrochemical methods. The results suggest that the GFA and microhardness of the amorphous alloys increase until the Nd content reaches 20at%. The corrosion potential and corrosion current density obtained from the Tafel curves indicate that the Mg35Cu40Nd25ternary alloy exhibits the best corrosion resistance among the investigated alloys. Notably, nanoporous copper (NPC) was synthesized through a single-step dealloying of Mg60−xCu40Ndx(x = 5, 10, 15, 20, and 25) ternary alloys in 0.04 mol·L−1H2SO4solution under free corrosion conditions. The influence of dealloying process parameters, such as dealloying time and temperature, on the microstructure of the ribbons was also studied using the surface diffusivity theory. The formation mechanism of dealloyed samples with a multilayered structure was also discussed. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

关键词： Corrosion Corrosion resistance Differential scanning calorimetry Glass Microhardness Neodymium alloys Ternary alloys

Asymmetric Baylis-Hillman Reaction between chiral Activated Alkenes and Aromatic Aldehydes in Me_(3)N/H_(2)O/Solvent Medium

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chinese Chemical Letters 2005年第11期16卷 1427-1430页

作者： Ke HE Zheng hong ZHOU hong Ying TANG Guo Feng ZHAO Chu chi TANG State Key Laboratory of Elemento-Organic Chemistry Institute of Elemento-Organic Chemistry Nankai University Tianjin 300071

chiral activated alkene, L-menthyl acrylate and （＋）-N-α-phenylethyl acrylamide, induced asymmetric Baylis-HiUman reaction of aromatic aldehydes was realized at 25℃ for 7 days in Me3N/H2O/solvent homogeneous medium. The corresponding Baylis-Hillman adducts were obtained in good chemical yield with moderate to excellent diastereoselectivity （up to 99% de）.

关键词： chiral activated alkene asymmetric Baylis-Hillman reaction aromatic aldehyde,diastereoselectivity

Decision-making model for risk management of cascade hydropower stations

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Journal of Southeast University(English Edition) 2008年第S1期24卷 22-26页

作者： Pan, Bangchuan chi, hong Xu, Jianguo Qi, Mingliang Institute of Policy and Management Chinese Academy of Sciences Beijing 100190 China Graduate University Chinese Academy of Sciences Beijing 100049 China

In a medium-term electricity market,in order to reduce the risks of price and inflow uncertainties, the cascade hydropower stations may use the options contract with electricity supply companies. A profit-based model for risk management of cascade hydropower stations in the medium-term electricity market is presented. The objective function is profit maximization of cascade hydropower stations. In order to avoid the risks of price and inflow uncertainties, two different risk-aversion constraints: a minimum profit constraint and a minimum conditional value-at-risk, are introduced in the model. In addition, the model takes into account technology constraints of the generating units, which includes reservoir flow balance, reservoir capacity limits, water discharge constraints, etc. The model is formulated as a mixed integer nonlinear programming problem. Because the search space of the solution is very large, a genetic algorithm is used to deal with the problem.

关键词： cascade hydropower station mixed integer nonlinear programming risk management medium-term electricity market

Queuing theory based analysis for packet jitter of mixed services

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The Journal of china Universities of Posts and Telecommunications 2014年第3期21卷 71-76页

作者： DONG Wen chi Xue-fen LIU Zi-chuan ZHU Yu-hong School of Communication Engineering Jilin University

Exploring theory and methods to analyze the impacts of non real-time services on jitter performance of real-time services is a quite challenging but meaningful job. This article puts forward a general theoretical method to calculate packet jitter in network node bearing mixed services. Based on queuing theory and Markov theory, the network node is modeled as a double-queue single-server and limited-cache queuing system with thresholds. Two-state Markov-modulated Bernoulli process （MMBP-2） and interrupted Bernoulli process （IBP） are used to model the arrival processes of real-time services and small data services respectively in a packet switched network. In order to depict the interaction between real-time services and small data services, a four-dimensional discrete-time Markov chain is implemented to describe the transition of the system states. By solving the system model, expressions for packet jitter are obtained. The results given by the model are then compared with the simulation results obtained by network simulator, version 3 （NS-3）.

关键词： jitter quality of service (QoS) queuing theory

Detecting changes in long-period site responses after the M_w 7.6 chi-chi earthquake, Taiwan, using strong motion records

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 217-228页

作者： Teng-To Yu chi-Shin Wu Youg-Sin Cheng Department of Resources Engineering Cheng Kung University (NCKU)

Temporal changes in site effects are obtained using the HVSR(horizontal-to-vertical spectral ratio) method and strong motion records after the M w 7.6 chi-chi earthquake, Taiwan. Seismic data recorded between 1995 and 2010 are used, comprising 3,708 data from 15 stations adjacent to the Chelungpu fault. Temporal fl uctuations are determined by analyzing the site effect variation using a time–frequency variation(TFV) diagram based on these seismic data. Stations adjacent to the fault show signifi cant disturbances in the resonance frequency at 16–26 Hz. Station TCU129 shows a 40% drop in fundamental frequency after the main shock, and a gradual return to the original state over nine years. For stations located farther from the fault zone, sudden changes in tectonic stress play a dominant role in temporal changes to the HVSR. An impact analysis of the directional factor confi rms our fi nding that the proximity of the fault to seismic stations has the most infl uence on data.

关键词： chi-chi earthquake horizontal-to-vertical spectral

Dearomative spirocyclization via visible-light-induced reductive hydroarylation of non-activated arenes

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chinese Chemical Letters 2022年第1期33卷 225-228页

作者： Zhuomin chi Yuzhen Gao Lei Yang Chunlin Zhou Meng Zhang Peiming Cheng gang Li College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117China Key Laboratory of Coal to Ethylene Glycol and Its Related Technology Center for Excellence in Molecular SynthesisFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

A visible-light-induced spirocyclizative hydroarylation via reductive dearomatization of a series of non activated arenes including 2-phenyl indoles and naphthalene derivatives under mild conditions is de *** intriguing chemoselective dearomative hydroarylation of 2-phenyl indoles is *** dearomative hydroarylation protocol rapidly delivers valuable spirocycles with carbon-carbon doub bonds from readily accessible aromatic precursors in a single step.

关键词： Visible-light-induced Non-activated arene Spirocyclization Dearomatization Reductive hydroarylation

Magnetization reversal behavior and first-order reversal curve diagrams in high-coercivity Zr-doped α-Fe/Nd_(2)Fe_(14)B nanocomposite alloys

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Rare Metals 2021年第5期40卷 1232-1238页

作者： Tian-chi Ji Min-Xiang Pan hong-Liang Ge Qiong Wu Peng-Yue Zhang Magnetism Key Laboratory of Zhejiang Province China Jiliang UniversityHangzhou 310018China

In the present work,the magnetization reversal behavior for the melt spinning(Nd_(0.8)Ce_(0.2))_(2)Fe_(12)Co_(2-x)Zr_(x)B(x=0,0.5)permanent alloys with high coercivity was investigated by analyzing the hysteresis curves and the recoil *** to the Zr-free alloy,the Zr-doped sample obtains higher magnetic properties:coercivity of H_(cj)=650.5 kA·m^(-1),squareness of H_(k)/H_(cj)=0.76 and maximum energy product of(BH)_(max)=131.0 kJ·m^(-3).The first-order reversal curves(FORCs)analysis was taken to identify optimal conditions of exchange coupling for the Zr-free and Zr-doped *** coercivity mechanism of theα-Fe/Nd_(2)Fe_(14)B nanocomposite alloys was analyzed by the angular dependence of the coercive field as measured for the Zr-doped *** results show that the magnetic reverse process of the Zr-doped sample can be explained by the pinning model.

关键词： Magnetization reversal Coercivity mechanism First-order reversal curve(FORC) Nanocomposite