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Deterministic secure quantum communication over a collective-noise channel

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Science China(Physics,Mechanics & Astronomy) 2009年第12期52卷 1913-1918页

作者： GU Bin PEI ShiXin SONG Biao zhong kun College of Math and Physics Nanjing University of Information Science and TechnologyNanjing 210044China

We present two deterministic secure quantum communication schemes over a collective-noise. One is used to complete the secure quantum communication against a collective-rotation noise and the other is used against a collective-dephasing noise. The two parties of quantum communication can exploit the correlation of their subsystems to check eavesdropping efficiently. Although the sender should prepare a sequence of three-photon entangled states for accomplishing secure communication against a collective noise,the two parties need only single-photon measurements,rather than Bell-state measurements,which will make our schemes convenient in practical application.

关键词： deterministic secure quantum communication quantum secure direct communication collective-noise channel single-photon measurements

Two New Norsesquiterpenes from Ixeris polycephala

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Chinese Chemical Letters 2006年第7期17卷 913-915页

作者： Yi Feng HAN kun GAO zhong Jian JIA State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

The chemical investigation of Ixeris polycephala afforded two new norsesquiterpenes, named as ixerols A and B （1-2）. Their structures were established based on spectroscopic methods including 2D NMR experiments. The... 详细信息

关键词： Ixeris polycephala Compositae ixerols A and B norsesquiterpene.

Microstructure and mechanical properties of WC-Co-based cemented carbide with bimodal WC grain size distribution

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Rare Metals 2023年第8期42卷 2809-2815页

作者： Rui-Jun Cao Chen-Guang Lin Xing-Cheng Xie zhong-kun Lin Powder Metallurgy and Special Materials Department General Research Institute for Nonferrous MetalsBeijing 100088China

In order to improve the wear resistance of coarse-grained WC-Co cemented carbides,the fine WC powder were used to reinforce the metallic *** WC-Co-based cemented carbides having bimodal WC grain size distributions were synthesized by liquid phase *** comparison,the cemented carbides having unimodal WC grain size distributions were *** microstructure,hardness,fracture toughness and wear resistance of these cemented carbides were *** results show that adding fine WC powder is an effective method to improve the wear resistance of coarsegrained WC-Co cemented *** WC size,mean free path and fracture toughness decrease with the addition of fine WC powder,while the hardness exhibits an opposite *** impact-wear coefficient of bimodal distribution cemented carbides is noticeably lower than that of the unimodal one with the same hardness,which means that the cemented carbides with bimodal grain structure have better combination of hardness and impact-abrasive wear *** impact-abrasive wear mechanism of the bimodal cemented carbides is that the fine WC grains prevent abrasive wear and the coarse WC grains prevent impact wear.

关键词： WC-Co cemented carbide Impact wearing Bimodal distribution Hardness Mean free path

Thermoelastic Correction in the Torsion Pendulum Experiment

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Chinese Physics Letters 2001年第1期18卷 7-9页

作者： HU zhong-kun WANG Xue-Li LUO Jun Department of Physics Huazhong University of Science and TechnologyWuhan 430074

The thermoelastic effect of the suspension fibre in the torsion pendulum experiment with magnetic damping was *** disagreement in the oscillation periods was reduced by one order of magnitude through monitoring the ambient temperature and thermoelastic *** also found that the period on uncertainty due to noise increases with the amplitude attenuation after thermoelastic correction.

关键词： torsion fibre ambient

Microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents during heat treatments

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Rare Metals 2024年第4期43卷 1786-1792页

作者： Yuan-Feng Xie Xing-Cheng Xie zhong-Wu Li Rui-Jun Cao zhong-kun Lin Qing Li Chen-Guang Lin Powder Metallurgy and Special Materials Research Department General Research Institute for Nonferrous MetalsBeijing100088China

The effects of cryogenic treatment(CT)and tempering-cryogenic treatment(TCT)on the microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents were *** binder phase,WC mean grain sizes,W solubility in the binder,relative magnetic s aturation,densities,hardness,wear resistance and second phase precipitation of cemented carbides with different heat treatments were *** results show that there are significant changes of microstructure and properties in the samples with CT and TCT,especially due to the precipitation of metastable nanoparticles W_(x)Co_(y)C_(z) in the binder during the heat treatments of CT and *** the simultaneous combination of microstructure and nanoparticle-reinforced binder,a dramatically improved combination of hardness and wear resistance of the samples after TCT has been achieved.

关键词： Cryogenic treatment Tempering Coarsegrained cemented carbide Carbon content Nanoparticlereinforced binder

Robustness analysis of O-FDE algorithm for dispersion compensation in coherent fiber optical communications

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Optoelectronics Letters 2024年第5期20卷 289-293页

作者： zhong kun ZENG Chenping DONG Jiaqiang WANG Baojiang LI Dan School of Information Technology Xichang UniversityXichang 615013China Key Laboratory of Liangshan Agriculture Digital Transformation of Sichuan Provincial Education Department Xichang615013China

The overlapping frequency domain equalization(O-FDE) in digital signal processing(DSP) is frequently employed to provide dispersion compensation in long-distance coherent fiber optical communications. However, the change in overlapping symbol length that occurs during the processing of the O-FDE algorithm will typically be influenced by the decision and zero filling of the last subblock, which is harmful to the robustness of the O-FDE algorithm. In this study, with a thorough robustness analysis on changing overlapping symbol length, we present a novel method for decision and zero filling of the last subblock and examine the correspondingly resulting error vector magnitude(EVM) and symbol error ratio(SER) under different values of optical signal-to-noise ratio(OSNR), chromatic dispersion, and overlapped symbol lengths.

关键词： fiber dispersion symbol

A facile route to tungsten oxide nanomaterials with controlled morphology and structure

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Particuology 2011年第5期9卷 517-521页

作者： Hsuan-Ching Lin Cherng-Yuh Su zhong-kun Yang Chung-Kwei Lin Keng-Liang Ou Institute of Atomic and Molecular Sciences Academia Sinica Taipei Taiwan China Institute of ManufacturingEngineering National Taipei University of Technology Taipei 106 Taiwan China Department of Materials Science and Engineering Feng-Chia University Taichung 407 Taiwan China Department of Oral Medicine Taipei Medical University Taipei 110 Taiwan China

Various tungsten oxide-based nanomaterials have been prepared by a modified plasma arc gas condensation technique without the use of catalysts or substrates. These products could be obtained by controlling the processing parameters during experiment. All the as-obtained samples were characterized by field emission gun scanning electron microscopy, high-resolution transmission electron microscopy, and X- ray diffraction techniques. The results revealed that as-prepared tungsten oxide nanomaterials （WO3, W190s5 and WsO14） with different phases and morphologies could be obtained by decreasing the oxygen content in the chamber. In addition, W18049 nanotubes and nanorod bundles were fabricated by con- trolling the Ar/O2 ratio under He plasma gas. W18Q9/TiO2 core-shell nanoparticles were also prepared by evaporating a dual target. The experimental results showed that the present technique is unique and feasible for the fabrication of nanomaterials for use in different applications.

关键词： Plasma arc gas condensation Titanium oxide Tungsten oxide Nanoparticle Nanorods

Sliding tribological characteristics of Ti48Zr20Nb12Cu5Be15 metallic glass matrix composites under different conditions

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Journal of Iron and Steel Research International 2018年第3期25卷 282-290页

作者： zhong-kun Bai Li-ming Du Ming Chen Min Zhang Xiao-hui Shi Hui-jun Yang College of Materials Science and Engineering TaiyuanUniversity of Technology Taiyuan 030024 Shanxi China

A systematic research on the tribological characteristics of Ti48Zr20Nb12Cu5Be15 metallic glass matrix composites was performed under different normal loads in dry condition and simulated seawater. The wear rate decreased with the increase in normal load under dry and simulated seawater conditions. The friction coefficient was lower in the dry condition than in the simulated seawater. The composite showed better wear resistance at lower loads （3, 5 and 10 N） hut poor wear resistance at higher loads （15 and 17 N） in the simulated seawater. The analysis of the worn surface illustrated that the wear mechanism in dry condition was plastic deformation, adhesive wear and abrasive wear at 3 and 5 N, while it was abrasive wear and adhesive wear at 10, 15 and 17 N. The wear mechanism in simulated seawater was abrasive wear, plastic deformation and adhesive wear at 3 N, adhesive wear at 10 N, and abrasive wear at 5, 15 and 17 N. At the same time, the corrosion occurred during wear tests in the simulated seawater.

关键词： Amorphous material Rapid solidification Friction Wear Corrosion

Let-7a gene knockdown protects against cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2016年第2期11卷 262-269页

作者： zhong-kun Wang Fang-fang Liu Yu Wang Xin-mei Jiang Xue-fan Yu Department of Neurology First Hospital Jilin University Department of Neurology Jilin Central Hospital Department of Hepatopancreatobiliary Surgery the Second Hospital of Jilin University

The micro RNA（mi RNA） let-7 was one of the first mi RNAs to be discovered, and is highly conserved and widely expressed among species. let-7 expression increases in brain tissue after cerebral ischemia/reperfusion injury; however, no studies have reported let-7 effects on nerve injury after cerebral ischemia/reperfusion injury. To investigate the effects of let-7 gene knockdown on cerebral ischemia/reperfusion injury, we established a rat model of cerebral ischemia/reperfusion injury. Quantitative reverse transcription-polymerase chain reaction demonstrated that 12 hours after cerebral ischemia/reperfusion injury, let-7 expression was up-regulated, peaked at 24 hours, and was still higher than that in control rats after 72 hours. Let-7 gene knockdown in rats suppressed microglial activation and inflammatory factor release, reduced neuronal apoptosis and infarct volume in brain tissue after cerebral ischemia/reperfusion injury. Western blot assays and luciferase assays revealed that mitogen-activated protein kinase phosphatase-1（MKP1） is a direct target of let-7. Let-7 enhanced phosphorylated p38 mitogen-activated protein kinase（MAPK） and c-Jun N-terminal kinase（JNK） expression by down-regulating MKP1. These findings suggest that knockdown of let-7 inhibited the activation of p38 MAPK and JNK signaling pathways by up-regulating MKP1 expression, reduced apoptosis and the inflammatory reaction, and exerted a neuroprotective effect following cerebral ischemia/reperfusion injury.

关键词： nerve regeneration cerebral ischemia/reperfusion injury let-7 mitogen-activated protein kinase phosphatase-1 apoptosis microglia inflammation mitogen-activated protein kinase neurons c-Jun N-terminal kinase gene knockdown brain injury neural regeneration