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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 615-621页

作者： Yong He Xue-feng liu fang Qin Jian-xin Xie Key Laboratory for Advanced Materials Processing (Ministry of Education) University of Science and Technology Beijing Beijing 100083 China

A deformation measurement method of interframe displacement was proposed in this paper. By online monitoring the shape di- mensions of both the deformation zone and its adjacent zone by machine vision, the initial and terminative positions of deformation were dynamically identified during dieless drawing, and the global monitoring and online closed-loop control of the deformation zone were achieved. The dieless drawing process was systematically carried out on NiTi shape memory alloy wires. It is shown that the deformation measurement method of interframe displacement can track the axial displacement of the wires, but this cannot be achieved by traditional machine vision. The initial and terminative positions of deformation can be accurately identified by this method. The proposed rectifying control technology can effectively decrease the wire diameter fluctuation during dieless drawing, that is, the standard deviation of the wire diameter fluctuation could be decreased fi＇om 0.30 to 0.08 mm after three passes of dieless drawing, indicating that the control system has a good rectifying ability.

关键词： wire drawing rectification deformation machine vision closed loop control systems nickel alloys sha^oe memory effect

Synthesis, Crystal Structure and Fluorescence Properties of a Terbium(Ⅲ) Complex with Biphenyl-2,3,3’,5’-tetracarboxylic Acid

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Chinese Journal of Structural Chemistry 2019年第6期38卷 985-990页

作者： LI Rong-fang ZHU xin-xin liu xin-fang FENG Xun Wang Li-Ya College of Chemistry and Chemical Engineering and Henan Key Laboratory of Function Oriented Porous Materials Luoyang Normal University

A new terbium complex based on biphenyl-2,3,3’,5’-tetracarboxylic acid（H4bptc） has been synthesized, {[Tb（Hbptc）（H2O）4]×H2O}n（1）. Its structure was determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra and TG analyses. Title complex crystallizes in monoclinic, space group P21/n with a = 14.090（2）, b = 8.0824（13）, c = 15.5591（17） ?, V = 1775.4（5） ?3, Mr = 576.22, Dc = 2.156 g/cm3, μ（Mo Kα） = 4.059 mm-1, F（000） = 1128, Z = 4, the final R = 0.027 and w R = 0.0726 for 3296 observed reflections（I > 2σ（I））. Complex 1 exhibits a 2 D layer structure, and such layers are further united together into a three-dimensional supramolecular structure through π···π interaction and intricate hydrogen bonding. The fluorescence excitation and emission spectroscopy of 1 showed that H4 bptc is a kind of highly efficient sensitizer for terbium（Ⅲ） ion. The title complex also displays efficient ligand sensitized luminescence in the visible region with long lifetime of 2.02 ms in the solid state.

关键词： terbium(Ⅲ)complex π…πinteraction luminescence fluorescence lifetime

Nondegenerate Four Wave Mixing in Rare-Earth Doped Fiber Under theInfluence of Coherent Population Trapping

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Chinese Physics Letters 2000年第4期17卷 275-276页

作者： GUO Yang MING Hai liu fang-xin XU Li-xin Structure Research Laboratory University of Science and Technology of ChinaHefei 230026 Department of Physics University of Science and Technology of ChinaHefei 230026 Department of Astronomy and Applied Physics University of Science and Technology of ChinaHefei 230026

By applying a strong coupling field between a lower state and the upper state of an allowed transition to ground,an enhancement of nondegenerate four wave mixing(NDFWM)with a resonantly enhanced third-order nonlinear susceptibility in a rare-earth doped fiber can be *** have derived an expression for the third-order nonlinear susceptibility using quantum theory and discussed the conversion efficiency for *** theoretical result shows that the conversion efficiency has a maximum value while the third-order nonlinear susceptibility shows constructive interference at the Rabi frequencyΩ_(23)=±-√Г2Г*** account of phase-mismatch,the frequency conversion efficiency has a maximum value over a certain small range of frequency separation(such as 0<△f<30 GHz at the wavelengthλ_(c)=1.55μm),and the frequency conversion range increases with increase of the third-order nonlinear susceptibility.

关键词： degenerate susceptibility nonlinear

A One-dimensional Cobalt Coordination Polymer Based on Biphenyl-2,3,3',5'-tetracarboxylic Acid and N-donor Ancillary Ligands: Crystal Structure and Magnetic Property

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Chinese Journal of Structural Chemistry 2015年第10期34卷 1558-1564页

作者： LI Rong-fang WANG Yu-fang liu xin-fang FENG Xun ZHANG Xiao-Yu DU De-Guang College of Chemistry and Chemical Engineering Luoyang Normal University Food and Bioengineering Department Henan University of Science and Technology Luoyang Huier Nano Science and Technology Co Ltd

Hydrothermal reactions of biphenyl-2,3,3A,5A-tetracarboxylic acid（H4bptc） with cobalt salt in the presence of 1,4-bis（2-pyridylmethyl）piperazin（bpmp） afforded one novel coordination polymer, namely, [Co（H2bptc）（bpmp）0.5（H2O）]n（1）. Its structure was established by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra and TG analysis. Complex 1 crystallizes in monoclinic, space group P21/c with a = 11.4839（11）, b = 16.6690（16）, c = 11.5559（11） A, V = 2201.8（4） A3, Mr = 539.35, Dc = 1.627 g/cm^3, μ（MoK α） = 0.841 mm-1, F（000） = 1108, Z = 4, the final R = 0.0309 and w R = 0.0705 for 4090 observed reflections（I 2σ（I））. Complex 1 displays a one-dimensional（1D） chain bridged by bpmp. Two carboxylic groups of H4 bptc ligand adopt μ01-η1：η1 and μ1-η1：η coordination modes to bridge adjacent Co（Ⅱ） ions together with bpmp ligand to give alternately arranged left- and right-handed helical chains. In addition, variable-temperature magnetic susceptibility measurements indicate that complex 1 shows weak antiferromagnetic interactions between the adjacent Co（Ⅱ） ions.

关键词： cobalt polymer diphenyl-2,3,3' 5'-tetracarboxylic acid 1,4-bis(2-pyridylmethyl)piperazin magnetic property

Synthesis of Novel Ferrocenyl-containing Thiazole Derivatives

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Chinese Chemical Letters 2006年第8期17卷 1002-1004页

作者： Ling SHAO Yah HU xin ZHOU Zhong JIN Jian Bing liu Jian xin fang State Key Laboratory of Elemento-Organic Chemistry Institute of Elemento-Organic Chemistry Nankai University Tianjin 300071

Novel ferrocenyl-containing thiazole derivatives have been synthesized from 2-amino-4-ferrocenyl-5-（1H-1, 2, 4-triazole-l-yl）thiazole and acyl chloride. And their structures were determined by 1H NMR and elemental a... 详细信息

关键词： Synthesis thiazole ferrocene.

Labeling polypeptide with ^(99m)Tc and bioactivity get back

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Nuclear Science and Techniques 2001年第2期12卷 99-104页

作者： LI Shao-Lin JIANG Xiao-Fei PANG Hua liu fang-xin SHI Qiong Department of Nuclear Medicine Chongqing University of Medical SciencesChongqing 400016

A method for labeling polypeptide (insulin) with technetium- 99(99mTc) was established without marked loss of biological activity. Following reduction of intrinsic disulfide bonds by mercaptoethanol and purification on a Sephadex G50 column, the polypeptide was labeled with 99mTc by transchelation from methylene diphosphonate (MDP). 99mTc labeled insulin was identified by thin layer chromatograph (TLC) and the change of blood sugar of mice injected, their hypoglycemic shock symptom was also observed. Six hours after labeling, the dissociation of labeled insulin was only 3%, Mom then on to 24 h, there was no more dissociation. The blood sugar concentration of mice injected with the mercaptoethanol-reduced insulin was (5.0±3.2)μmol.L-1, while those injected with the original insulin was (1.4±1.2)μmol.L-1, the difference was significant (Q test, p <0.01). Blood sugar concentration of the mice was 0.3±0.2μmol.L-1 for the labeled insulin, and was about the same with that for the original insulin. The labeling efficiency was 74.31% for the labeled insulin, whereas the original insulin cannot be labeled with 99mTc. The result suggests that while disulfide bonds of polypeptide were reduced by mercaptoethanol, it became free sulfhydryl group, and its bioactivity descended. Then free sulfhydryl group was chelated with 99mTc under mild condition, restablishing the disulfide bond, therefore, the bioactivity came back. The 99mTc-labeled insulin was stable during 24h.

关键词：肽生物试样 Tc标记胰岛素

Time Series Analysis on the Ratio for Pixels with Abnormal Brightness Temperature Increase and Its Variation Before Some Earthquakes with M_S≥5.0 in the Taiwan Region

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Earthquake Research in China 2007年第4期21卷 437-444页

作者： liu fang xin Hua Zhang Tiebao Lu Qian Ren Yuexia Earthquake Administration of Sichuan Province Chengdu 610041 China

In the study of the application of MODIS satellite remote sensing data to earthquake prediction, the paper puts forward for the first time a quantitative method to estimate the ratio for the pixels with abnormal brightness temperature (BT) increase and a preliminary scheme for cloud removal. The principle is that, firstly, the cloudless data observed by the same satellite at the same period of time but in different days (usually 1 day to 3 days) are mosaiced to get high ratio of clear sky, and then the BT variation curve and mean square difference (MSD) of each pixel are calculated with the data from the covered area to determine daily whether the BT data of the day is normal or not at a certain pixel by using double the MSD as the criterion. The ratio for the pixels with abnormal BT increase can be calculated by dividing the total number of abnormal pixels with the total pixels of the whole area. Analysis on a series of recent earthquakes in the Taiwan Region shows that the ratio for pixels with abnormal BT increase, which normally undulates around zero, has a sudden enhancement 1 day to 20 days before medium-strong earthquakes. It is expected that a new method for identifying earthquake auspice could be found through special studies in regions with frequent seismic activity by analyzing the change of the ratio for the pixels with abnormal BT increase from MODIS satellite remote sensing infrared (IR) information from which the effect of clouds has been removed to a certain extent.

关键词： MODIS Satellite thermal infrared data Ratio for pixels with abnormal BTincrease Earthquake

Highly mass activity electrocatalysts with ultralow Pt loading on carbon black for hydrogen evolution reaction

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 182-190页

作者： Shaorou Ke Yajing Zhao xin Min Yanghong Li Ruiyu Mi Yangai liu Xiaowen Wu Minghao fang Zhaohui Huang Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastersNational Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of Geosciences(Beijing)Beijing 100083China

Pt-based nanocatalysts offer excellent prospects for various ***,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable *** this study,nanocatalysts with ultralow Pt content,excellent performance,and carbon black as support were prepared through in-situ ***~2-nm particles uniformly and stably dispersed on carbon black because of the strong s-p-d orbital hybridizations between carbon black and Pt,which suppressed the agglomeration of Pt *** unique structure is beneficial for the hydrogen evolution *** catalysts exhibited remarkable catalytic activity for hydrogen evolution reaction,exhibiting a potential of 100 mV at 100 mA·cm^(-2),which is comparable to those of commercial Pt/C *** activity(1.61 A/mg)was four times that of a commercial Pt/C catalyst(0.37 A/mg).The ultralow Pt loading(6.84wt%)paves the way for the development of next-generation electrocatalysts.

关键词： hydrogen evolution reaction ultralow platinum in-situ synthesis ultrasound

Post-tunable salt gel electrolytes toward flexible supercapacitor switches

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Journal of Energy Chemistry 2025年第1期100卷 114-124页

作者： Hui Wang Shuang Chen Xuming liu Qin Zhang xin liu Polymeric and Soft Materials Laboratory School of Chemistry and Life Science and Advanced Institute of Materials Science Changchun University of Technology Polymeric and Soft Materials Laboratory School of Chemical Engineering and Advanced Institute of Materials Science Changchun University of Technology

Convertible hydrogel supercapacitors have emerged as promising energy storage devices in switches,diodes, and transistors. However, inherent weaknesses in ionic conductivity, mechanical properties,and water retention of hydrogel electrolytes seriously hinder their development. Inspired by the hardness conversion of sea cucumber skin, a conductivity and mechanics dual-tunable salt gel electrolyte is successfully designed. The salt gel presents a reversible switching of conductors-insulators and a mechanical regulation between softness and hardness via the dissolution-crystallization transition of sodium acetate trihydrate（SAT）. Meanwhile, the salt gels spontaneously grow a layer of “armor” through saturated phase-change salt crystals effectively reducing water evaporation of hydrogel ***, this phase-change soft-rigid conversion strategy will expand the capabilities of gel-based flexible supercapacitors(area capacitance: 258.6 mF cm-2), and the capacitance retention rate could still reach 86.9% after 3000 cycles at high temperatures. Moreover, the salt gel supercapacitor is potentially used in over-heat alarm systems. It is anticipated that the strategy of conductivity and mechanics of dual-tunable salt gel would provide a new perspective on the development of energy storage devices,wearable electronics, and flexible robots.

关键词： Capacitance

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古文字歧读释例

安徽大学学报（哲学社会科学版） 2008年第5期32卷 79-86页

作者：刘信芳安徽大学历史系安徽合肥230039

最早对古文字歧读现象进行理论说明的是章太炎,汤炳正对《说文》歧读字研究作出了重要贡献。参照汤炳正的分类,战国简帛中的歧读字有义同歧读、义近歧读、义异歧读、声符歧读等。文字异形是导致战国文字多歧读的重要原因。

关键词：古文字歧读文字异形