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A Novel 3D Supramolecular Network Constructed from [Cu(4,4'-bipyridine)(O_2CMe)_2]_2 Molecular Ladders by Hydrogen Bonding

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1365-1368页

作者： YANG E WANG Xiao-Qin QIN Ye-Yan College of Chemistry ＆ materials science Fujian Normal University Fuzhou 350007 China Fujian institute of research on the Structure of Matter The Chinese Academy of Sciences Fuzhou 350002 China

The title complex, {[Cu2（4,4＇-bipyridine）2（μ-O2CMe）2（O2CMe）2],H2O}n 1, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 13.4474（5）, b = 11.7566（2）, c = 19.5380（6）A, β = 92.930（2）°, V = 3084.84（16） A^3, Z = 4, Cu2C28N409H30, Mr = 693.64, Dc = 1.494 g/cm^3, F（000） = 1424 and μ（MoKα） = 1.436 mm^-1. With the use of 2062 observed reflections （I 〉 2σ（I））, the structure was refined to R = 0.0769 and wR = 0.2154. In complex 1, the dimeric copper acetate units are linked through 4,4’-bipyridine to yield ID molecular ladders. These ladders are connected via O-H…O hydrogen bonds to generate 2D layers, which are further linked through C-H…O hydrogen bonds to give a 3D supramolecular network.

关键词： molecular ladder dimeric copper acetate 3D supramolecular network

Enhancement of adjustable localized surface plasmon resonance in ZnO nanocrystals via a dual doping approach

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science Bulletin 2017年第10期62卷 693-699页

作者： Yusufkadie Yibi Jiawei Chen Jie Xue Jizhong Song Haibo Zeng Ministry of Industry and Information Technology of the China Key Laboratory of Advanced Display materials and Devices Institute of Optoelectronics & Nanomaterials Collegeof Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China

Recently, the localized surface plasmon resonance （LSPR） concept was expanded from noble metals to doped semiconductor nanocrystals （NCs）. However, the strengthening of the intrinsically very weak LSPR in NCs remains a great challenge for its applications in optics, electronics and optoelectronics fields. In this work, we report on the remarkable strengthening and controllability of LSPR in ZnO through a dual-doping strategy. First, high quality In-doped ZnO （IZO） NCs with intense LSPR were synthesized by a simple single-pot method. Importantly, the LSPR can be tuned by simply adjusting the concentration of In dopant, as well as by UV light irradiation （photo-induced doping）. The pattern of electricity of an IZO NC film matches the shift of LSPR independent of dopant concentration. The UV light irradiation clearly enhanced the electrical properties of the films （350 fl/sq） due to increase carrier density explained by LSPR and confirmed by X-ray photoelectron spectroscopy, The IZO NCs can be easily dispersed in various organic solvents and serve as inks for assembling uniform films via solution processes. These IZO NC ink is promising for application in next-generation solution-based field effect transistors and other optoelec- tronic devices.

关键词： Doped zinc oxide Colloidal nanocrystals LSPR Electrical properties UV treatment Ink

OBSERVATIONAL ANALYSIS OF ASYMMETRIC DISTRIBUTION OF CONVECTION ASSOCIATED WITH TROPICAL CYCLONES “CHANCHU” AND “PRAPIROON” MAKING LANDFALL ALONG THE SOUTH CHINA COAST

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Journal of Tropical Meteorology 2010年第2期16卷 171-180页

作者：袁金南周文黄辉军廖菲 Guangzhou institute of Tropical and Marine Meteorology CMA Laboratory for Atmospheric research Department of Physics and Materials Science City University of Hong Kong

Observational data of mesoscale surface weather stations and weather radars of Guangdong province are employed to analyze the asymmetric distribution of convection prior to, during and after landfall for tropical cyclones of Chanchu and Prapiroon making landfall on the south China coast in 2006. The results showed that strong convection is located in the eastern and northern sectors of the landfalling Chanchu and Prapiroon, namely in the front and right portions of the TC tracks, for a period of time starting from 12 h prior to landfall to 6 h after it. Their convection also had distinct differences in the vertical direction. The analysis indicated that although the landfall of Chanchu and Prapiroon has the same asymmetric distribution of convection, the causes are not exactly the same. The asymmetric distribution of convection in the case of Chanchu is mainly correlated with the impacts of a strong environmental vertical wind shear, low-level horizontal wind shear, and low-level convergence and divergence. In the case of Prapiroon, however, the asymmetric distribution of convection is mainly associated with the impacts of low-level convergence and divergence.

关键词： asymmetric distribution of convection tropical cyclones Chanchu and Prapiroon observation alanalysis

Microstructure of Epitaxial La_(0.7)Ca_(0.3)MnO_3 Thin Films Deposited by Direct Current Magnetron Sputtering on LaAlO_3 Substrate

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Journal of materials science & Technology 2009年第3期25卷 336-340页

作者： Mingguang Wang Hengqiang Ye Department of sciences Northeastern University Shenyang 110004 China Shenyang National Laboratory for materials science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Transmission electron microscopy （TEM） and high resolution electron microscopy （HREM） have been used to study the microstructural properties of La0.7Ca0.3MnO3 films on （001） LaAlO3 substrates prepared by direct current magnetron sputtering technique. The as-grown thin films with different thickness are perfectly coherent with the substrates. The film suffers a tetragonal deformation in the area near the interface between the film and the substrate. With increasing thickness, the film is partially relaxed. It was found that La0.7Ca0.3MnO3 films consist of two types of oriented domains described as：（1）（110）f[001]f｜｜（001）s[100]s and （110）f[001]f｜｜（001）s[100]s and （2）（100）f[001]f｜｜（001）s[010]s and （110）f[001]f｜｜（001）s[010]s. Upon annealing, the film is relaxed by the formation of misfit dislocations. Other than misfit dislocations, two types of threading dislocations with Burgers vector of 〈100〉 and 〈110〉 were also identified.

关键词： Colossal magnetoresistance Microstructure Film Dislocation

Nanocrystalline Nd_2Fe_(14)B/α-Fe permanent magnet

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中国有色金属学会会刊：英文版 2002年第4期12卷 723-725页

作者：倪建森徐晖朱明原李强周邦新董远达 institute of materials science and Engineering Shanghai University 上海 200072

Nd 8.5 Fe 75 Co 5Cu 1Zr 3Nb 1B 6.5 bonded magnet was prepared by melt spinning ( v s=18?m/s) and subsequent heat treatment (670?℃, 4?min). Excellent magnetic properties of the bonded magnet were achieved: B r=0.68T, i H c=620.3?kA/m, ( BH ) max =74?kJ/m 3. The addition of Cu and Zr elements shows to be advantageous in improving an intrinsic coercivity and squareness of hysteresis loop, as well as energy product. It has a remarkable remanence enhancement and the isotropic saturation remanence ratio M r/ M s is 0.83.

关键词：永磁材料钕铁硼永久磁铁晶粒尺寸

Microstructure and thermal and electric conductivities of high dense Mo/Cu composites

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中国有色金属学会会刊：英文版 2005年第S3期15卷 110-114页

作者：陈国钦武高辉朱德志张强姜龙涛 School of materials science and Engineering Harbin Institute of Technology Harbin 150001 China

For electronic packaging applications, Mo/Cu composites with volume fractions of 55%, 60% and 67% Mo were fabricated by the patented squeeze-casting technology. The microstructures and thermal and electric conduction properties of the Mo/Cu composites were investigated. The results show that Mo particles are homogeneous and uniform, and the Mo-Cu interfaces are clean and free from interfacial reaction products and amorphous layers; the densifications of the Mo/Cu composites are higher than 99%. The thermal conductivities of Mo/Cu composites range from 220 to 270W/(m·℃) and decrease with an increase in volume fraction of Mo content. The thermal conductivities agree well with the predicted values of theoretical models. The electric conductivities of Mo/Cu composites are in the range of 2228MS/m and decrease with the increase of Mo content. The achievement of higher thermal and electric conduction is attributed to the full densities and high purity Mo/Cu composites, which are attained through the cost-effective squeeze-casting technology processes.

关键词： Mo/Cu composites microstructure densification thermal conductivity electric conductivity

Free-space communication based on quantum cascade laser

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Journal of Semiconductors 2015年第9期36卷 85-88页

作者：刘传威翟慎强张锦川周予虹贾志伟刘峰奇王占国 Key Laboratory of Semiconductor materials science Institute of SemiconductorsChinese Academy of Sciences

A free-space communication based on a mid-infrared quantum cascade laser （QCL） is presented. A room-temperature continuous-wave distributed-feedback （DFB） QCL combined with a mid-infrared detector com- prise the basic unit of the communication system. Sinusoidal signals at a highest frequency of 40 MHz and modu- lated video signals with a carrier frequency of 30 MHz were successfully transmitted with this experimental setup. Our research has provided a proof-of-concept demonstration of space optical communication application with QCL. The highest operation frequency of our setup was determined by the circuit-limited modulation bandwidth. A high performance communication system can be obtained with improved modulation circuit system.

关键词： quantum cascade laser free-space communication video transmission

Electronic Processes in Phthalocyanine Solids

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science China Mathematics 1994年第4期37卷 497-503页

作者：汪茫陈红征沈菊李杨士林 institute of Polymer science and materials Zhejiang University Hangzhou 310027 PRC

The positive or negative photoconductivity effects are found between the component of phthalocyanine dimixing composites and the photoconductivity by dimixing method. The relations between the crystalline forms and electronic structure of the composites and the photoconductivity are further studied through X-ray and XPS. The results indicate that the composites may be a kind of new uniform eutectic composites, which can enhance or reduce the partial charge transfer processes from phthalocyanine rings to metals, and the processes are exactly correspondent with the positive or negative photoconductivity effects. A model of gradually transferred charge in the phthalocyanine solids is put forward, which can better explain the electronic processes in the phthalocyanine solids.

关键词： phthalocyanine dhnixing photoconductivity electronic processes eutectic composite.

ATR-FTIR study of Bacillus sp. and Escherichia coli settlements on the bare and Al_2O_3 coated ZnSe internal reflection element

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Chinese Chemical Letters 2019年第1期30卷 115-119页

作者： Rongqiao Chen Chune Guo Wubo Chu Nan Jiang He Li Key Laboratory of Marine materials and Related Technologies CAS Zhejiang Key Laboratory of Marine Materials and Protective Technologies Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Nano science and Technology institute University of Science and Technology of China

Marine microorganism accumulated on the surface of ships or pipelines would accelerate fouling organisms, such as mussels and barnacles, adhered on the surface. It was significant to understand the bio-interaction between the microorganisms and the surface. Attenuated total reflection(ATR) Fourier transform infrared(FTIR) spectroscopy was used to study the initial stages of marine microorganism adhering to surfaces, because it could probe the microorganism interaction to the surface regardless of the water interference. Bacillus sp. and Escherichia coli were selected to study the initial attachment on different surfaces, because they were typical fouling microorganisms and showed opposite Gram stain results. The assays were conducted respectively in dried and settled bacteria on two different surfaces(ZnSe, Al2 O3 coated on ZnSe). IR spectra of settled bacteria showed amide I band red shift and amide II band blue shift in aqueous environment on both surfaces compared with the dry bacteria. The reasons of amide bands shift were investigated and it was discovered that the hydrogen bond between the water and the protein of the bacteria led to the protein secondary structure change. ATR-FTIR provided an approach to study the attachment process and showed dynamic changing process on the surface, and it could be an appropriate approach to study the interaction between proteins and chemicals.

关键词： FTIR-ATR Bacteria settlement Secondary structure Surface interaction