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Effect of vacuum annealing on the characteristics of composite pellets containing DBSA-doped polyaniline and Fe nanoparticles

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 236-241页

作者： qing Wu Hong Qiu Chun-ying fang Kun fang School of Applied Science University of Science and Technology Beijing Beijing 100083 China Material Research Center Beijing Institute of Science and Technology Beijing 100081 China

The DBSA-PANI-Fe composite powder with 50wt% of Fe nanoparticles was prepared by mechanically mixing the DBSA-doped polyaniline powder and Fe nanoparticles. The composite powder was compacted to pellets and the pellets were annealed in vacuum at 443,493,543, and 593 K for 60 and 120 min. The conductivity of the pellet increases markedly with increasing the annealing temperature up to 493 K, and then decreases with further increasing the annealing temperature. When the pellet was annealed at 493 K for 60 min, the increment of conductivity reaches a maximum value, and the conductivity is 2.6 times as large as that of the pellet unannealed. The conductivities of the pellets annealed under the conditions of 543 K/120 min, 593 K/60 min, and 593 K/120 min are lower than the conductivity of the pellet unannealed. For all the pellets, the variation in conductivity with temperature reveals that the charge transport mechanism can be considered to be 1-D variable-range-hopping （1-D VRH）. The composite pellet shows a magnetic hysteresis loop independent of the annealing condition. The saturation magnetization is about 5.4×10^4 emu/kg. The saturation field and the coercivity are estimated to be 4.38×10^5 and 3.06×10^4 A/m, respectively. The crystalline structure ofFe nanoparticles in the composites does not change with the annealing condition. The annealing condition cannot destroy the polymer backbones.

关键词： doped polyaniline dodecylbenzene sulfonic acid (DBSA) Fe nanoparticles vacuum annealing structure conductivity magnetization

Michael Addition Reaction without Catalyst: The Synthesis of 2-Amino-5, 6, 7, 8-tetrahydro-5-oxo-4-aryl-7, 7-dimethyl- 4H-benzo-[b]-pyran Derivatives

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Chinese Chemical Letters 2002年第5期13卷 393-395页

作者： Shu Jiang TU Xiao Hong LIU Heng Jun MA da qing SHI fang LIU Department of Chemistry Xuzhou Normal UniversityXuzhou 221009

A series of tetrahydrobenzo-[b]-pyran derivative was synthesized by the reaction of arylmethylene malononitrile or arylmethylene cyanoacetate with dimedone in ethylene glycol at 80C without catalyst. The structures o... 详细信息

关键词： Benzo-[b]-pyran dimetone ethylene glycol.

Determination of the neutron skin thickness from interaction cross section and charge-changing cross section for B,C,N,O,F isotopes

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Nuclear Science and Techniques 2016年第3期27卷 153-158页

作者： Xiu-fang Li De-qing fang Yu-Gang Ma Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The effective neutron and proton root-meansquare radius of stable and unstable nuclei(^(12-15,17)B,^(12-20)C,^(14-21)N,^(16-24)O and ^(18-21,23-26)F) were deduced from the charge-changing cross section,σ_(cc),and the interaction cross sections,σ_I,by using a statistical abrasion-ablation model *** extracted proton radii are in good agreement with the data from the Atomic data and Nuclear data Tables within the ***,we can observe that the neutron skin thickness increases monotonously with the increasing neutron number in these isotopes,which is consistent with the systematical trend of theoretical calculations.

关键词：中子皮厚度作用截面同位素变化截面电荷均方根半径测定不稳定核

High mobility ultrathin ZnO p–n homojunction modulated by Zn_(0.85)Mg_(0.15)O quantum barriers

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Chinese Physics B 2018年第3期27卷 464-468页

作者： Jing-Jing Yang qing-qing fang Wen-Han Du Ke-Ke Zhang da-Shun Dong School of Physics and Materials Science Anhui UniversityHefei 230601China Changzhou Institute of Technology Changzhou 213002China School of Materials Science and Engineering Nanyang Technological UniversitySingapor

The adding of ZnMgO asymmetric double barriers(ADB)in p-ZnO2(Li,N)/n-ZnO homojunction affects the p-n junction device performance *** different homojunctions are fabricated on Si(100)substrates by pulsed laser deposition;one is the traditional p-ZnO2(Li,N)/n-ZnO homojunction with different thicknesses named as S_(1)(250 nm)and S2(500 nm),the other is the one with ADB embedded in the n-layer named as Q(265 nm).From the photoluminescence spectra,defect luminescence present in the S-series devices is effectively limited in the Q *** current-voltage curve of the Q device shows Zener-diode rectification property because the two-dimensional electron gas tunnels through the narrow ZnMgO barrier under a reverse bias,thus decreasing the working p-n homojunction thickness from 500 nm to 265 *** ADB-modified homojunction shows higher carrier mobility in the Q *** electroluminescence of the ZnO homojunction is improved in Q compared to S_(2),because the holes in p-type ZnO(Li,N)can cross the wide ZnMgO barrier under a forward bias voltage into the ZnO quantum ***,electron-hole recombination occurs in the narrow bandgap of n-type ZnO,creating an ultraviolet light-emitting diode using the ZnO homojunction.

关键词： ZnO p-n homojunction light-emitting diodes ZnMgO asymmetric double barriers

New chaos M-ary modulation method and its application in communications

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 77-83页

作者： FU Yong-qing ZHANG fang College of Information and Communication Engineering Harbin Engineering University Harbin 150001 China

At present, chaotic communications have been widely studied. However, these researches mainly focus on the binary systems while the researches of M-ary chaotic communications are not extensive. To change the situation, a chaos M-ary modulation method based on phase plane partition of Hamilton map is proposed. Firstly, the chaotic model of Hamilton map and its phase plane features are described, and then the way of creating the chaos M-ary modulation is discussed. Next, to evaluate the proposed method, the system simulation results and analysis are given. Finally, the chaos M-ary modulation method is applied to communications.

关键词： chaos M-ary modulation Hamilton map initial value mapping method phase plane partition

Electroacupuncture Attenuates Ischemic Brain Injury and Cellular Apoptosis via Mitochondrial Translocation of Cofilin

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Chinese Journal of Integrative Medicine 2021年第9期27卷 705-712页

作者： CHEN Bin LIN Wan-qing LI Zuan-fang ZHONG Xiao-yong WANG Jing YOU Xiao-fang ZHAO Hong-jia QI da-shi Department of Rehabilitation Medicine and National Clinical Research Base of Traditional Chinese Medicine the Affiliated People's Hospital of Fujian University of Traditional Chinese MedicineFuzhou(350004)China Academy of Integrative Medicine Fujian University of Traditional Chinese MedicineFuzhou(350108)China Shanghai Key Lab of Birth Defect Children's Hospital of Fudan UniversityShanghai(200032)China

Objective:To investigate the potential mechanisms of electroacupuncture(EA)to prevent ischemic ***:The method of middle cerebral artery occlusion(MCAO)was employed to establish a rat model of ischemic ***-eight Sprague-dawley rats were divided into the sham group,MCAO+EA control(EC)group,and MCAO+EA(EA)group according to a random number table(n=26 per group).EA was applied to the acupoints of Baihui(DU 20)and Shenting(DU 24)5 min and 6 h,respectively after the onset of MCAO for 30 *** in the sham and EC groups received only light isoflurane anesthesia for 30 min after *** neuroprotective effects of EA were evaluated by rota-rod test,neurological deficit scores and infarct ***,Nissl staining and immunostaining were performed to examine brain damage,rod formation,cellular apoptosis,and neuronal loss induced by *** activities of caspase-3,and expression levels of cofilin and p-cofilin in mitochondria and cytoplasm after ischemic injury were determined by Western ***:Compared with the EC group,EA significantly improved neuromotor function and cognitive ability after ischemic stroke(Pdation in the cortical penumbra area compared with the EC rats(Pdamage(infarct volume and neuropathy),cellular apoptosis and neuronal loss induced by ischemia were remarkably suppressed by EA in the cortical penumbra of rats(P<0.05 or P<0.01).Conclusion:EA treatment after ischemic stroke may attenuate ischemic brain injury and cellular apoptosis through the regulation of mitochondrial translocation of cofilin,a novel mechanism of EA therapy.

关键词： electroacupuncture cofilin apoptosis ischemic stroke mitochondrial translocation Chinese medicine

Numerical Evaluation of External Effects on Interspecific Interacting Populations

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International Journal of Automation and computing 2016年第2期13卷 133-141页

作者： Xiao-Yu Zhang qing fang Department of Mathematics College of ScienceBeijing Forestry University Department of Mathematical Sciences Faculty of ScienceYamagata University

In this paper, effects of environmental and hunting parameters on the interspecific interacting populations are considered by applying the Rosenzweig-MacArthur model with the Holling type II functional response. Attenuating functions of the carrying capacity are introduced with a concern on the hunting parameters. We carry out numerical study to investigate how the population densities behave when environmental quantities change. We obtain the Hopf bifurcation diagrams from numerical results.

关键词： Interspecific interaction predator-prey system carrying capacity hunting effect Hopf bifurcation.

On the Fekete and Szego Problem for Starlike Mappings of Order α

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Acta Mathematica Sinica,English Series 2017年第4期33卷 554-564页

作者： qing Hua XU fang fang Tai Shun LIU College of Mathematics and Information Science JiangXi Normal University Nanchang 330022 P. R. China Department of Mathematics Huzhou University Huzhou 313000 P. R. China

Let Sα*be the familiar class of normalized starlike functions of order α in the unit disk. In this paper, we establish the Fekete and Szeg? inequality for the class Sα*, and then we generalize this result to the un... 详细信息

关键词： Fekete–Szego problem starlike mappings of order α sharp coefficient bound

Comparison Properties for Asymptotically Tracially Approximation C^(*)-algebras

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Acta Mathematica Sinica,English Series 2023年第5期39卷 863-884页

作者： qing Zhai FAN Xiao Chun fang College of Education Shanghai Jian Qiao UniversityShanghai 201306P.R.China Department of Mathematics Shanghai Maritime UniversityShanghai 201306P.R.China Department of Mathematics Tongji UniversityShanghai 200092P.R.China

We show that the following properties of the C*-algebras in a class P are inherited by simple unital C*-algebras in the class of asymptotically tracially in P :(1) n-comparison,(2) α-comparison(1 ≤ α < ∞).

关键词： C*-algebras asymptotically tracially approximation Cuntz semigroup