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Journal of Environmental Sciences 2006年第1期18卷 76-82页

作者： hu Chun LIN Lan-yu hu Xue-xiang Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beij ing 100085 China

The morphology of supported metal nanoparticles on TiO2/silical gel （TSO） and photothermal synergism were investigated for destruction of ethylene. During photocatalytic deposition of metal nanopartilces, the effects of pH and light intensity on the morphology of coated platinum, palladium, gold on TiO2/silical gel were studied. Moreover, these catalysts were characterized by TEM, UV-Vis DRS. The pH of preparing solution have strong influence on dispersion, size and sites of Pt, Pd and Au on TSO, which were controlled by the electrostatic binding of HPtCl5^- AuCl4^- and TiOH2^＋, Pd^2＋ and TiO^- respectively. Platinum, gold and palladium nanoparticles were uniformly highly dispersed on the titanol sites not silanol of TiO2/silical gel under pH=2, pH =9.9 respectively. For the photodegradation of ethylene, they show higher photothermal efficiency than those prepared with other pH conditions under UV illumination in a non-circulating photoreactor. The optimum weight loadings of Pt, Au, and Pd were 0.25 wt%, 0.5 wt%, 1 wt%, respectively. The synergistic effect enhanced ethylene removal and CO2 production. Thcse results verify that the best photothermal synergistic effect depends on the dispersion, size of noble metal nano-particles. FTIR analyses of the used Pt-, Pd-TSO catalysts indicated that no significant by-products were accumulated on the surface of the catalysts, leading to them longer lifetime.

关键词： photodeposition TiO2/silical gel noble metal dispersion photothermal synergism

Systematic comparison of the effectiveness of radial artery and saphenous vein or right internal thoracic artery coronary bypass grafts in non-left anterior descending coronary arteries

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第4期12卷 273-279页

作者： xiang hu Qiang ZHAO Department of Cardiac Surgery Ruijin Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200025 China

Coronary artery bypass grafting surgery is increasingly being carried out on patients with multi-vessel coronary artery disease,but the best grafting candidate for non-left anterior descending coronary arteries is *** research sought to systematically compare the efficacies and safeties of coronary bypass with radial artery and other available grafts.A systematic literature retrieval was performed for all clinical trials comparing the outcomes of coronary artery bypass surgery with radial artery and other grafts in PubMed,EMBASE,and the Cochrane *** eligible clinical studies,comparing radial artery and great saphenous vein grafts,were found between 1966 and 2010:one prospective non-randomized and six prospective randomized *** pooling analysis obtained a relative risk of 0.507 (P<0.05) of graft occlusion in radial arteries compared with great saphenous *** was a significantly lower infection rate in arms (i.e.,harvest sites for radial arteries) relative to legs (harvest sites for veins),with a pooled relative risk of 0.140 (P<0.05).From the reports on mortality after follow-up ranging from one year to six years,there was no significant difference in mortality between the two graft types (P=0.927).In addition,four cohort controlled trials for radial and right internal thoracic artery grafts were *** radial graft was associated with less cardiac related events relative to the right internal thoracic artery graft (P=0.014),but with comparable mortality and comparable rates of repeat percutaneous transluminal coronary *** with radial arteries seemed to have a lower occlusion rate and a lower graft harvest site infection rate than those with great saphenous *** there were fewer cardiac related events with radial arteries relative to the right internal thoracic artery *** studies are needed to confirm these findings concerning the favorable outcomes of coronary artery bypass grafting with radia

关键词： Coronary artery bypass grafting (CABG) Arterial grafts Meta-analysis

Tensor Couplings of ω- and ρ-Mesons with Nucleons in a Derivative Scalar Coupling Model for Finite Nuclei

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Chinese Physics Letters 2001年第7期18卷 891-893页

作者： GUO hua hu xiang Department of Technical Physics and MOE Laboratory of Heavy Ion Physics Peking UniversityBeijing 100871

Theω-andρ-meson tensor couplings to nucleons in a derivative scalar coupling model for finite nuclei are *** influences of the tensor couplings on the binding energies per nucleon,the root-mean-square charge radii,spin-orbit splittings and single particle energies are *** obtained results show that the spin-orbit splittings for finite nuclei are more sensitive to theω-meson tensor coupling.

关键词： tensor coupling meson

Robust 3D network architectures of MnO nanoparticles bridged by ultrathin graphitic carbon for high-performance lithium-ion battery anodes

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Nano Research 2018年第2期11卷 1135-1145页

作者： Jingchun Jia xiang hu Zhenhai Wen Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou China Fujian Provincial Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou China

A strategy was developed to fabricate a set of MnO@C nanohybrids with MnO nanopartides （NPs） embedded in an ultrathin three-dimensional （3D） carbon framework for use as anode materials for lithium-ion batteries （LIBs）. The 3D carbon frameworks provide MnO NPs with electrical pathways and mechanical robustness, which efficiently improved the reaction kinetics, prevented the MnO from fracturing and agglomerating, and limited the formation of a solid electrolyte interface （SEI） at the MnO-electrolyte interface. Benefitting from the unique 3D framework structure, the MnO/C nanohybrids carbonized at 500 ℃ exhibited a highly reversible specific capacity of 1,420 mAh.g-1 at 0.2 A.g-1, excellent cycling stability with 98% capacity retention, and enhanced rate performance of 680 mAh-g-1 at 2 A.g-L The feasibility of the large-scale production of such MnO/C nanohybrids, associated with their outstanding Li-ion storage properties, opens a promising avenue for the development of high-performance anodes for next- generation LIBs.

关键词： network architectures ultrathin carbon MnO Li-ion batter anode

A fast decoupled ISAR high-resolution imaging method using structural sparse information under low SNR

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Journal of Systems Engineering and Electronics 2019年第3期30卷 492-503页

作者： xiang Long LI Shaodong YANG Jun CHEN Wenfeng xiang hu Department of Air Defense Early Warning Equipment Air Force Early Warning Academy Wuhan 430019 China Unit 93253 of the PLA Dalian 116000 China

Inverse synthetic aperture radar (ISAR) image can be represented and reconstructed by sparse recovery (SR) approaches. However, the existing SR algorithms, which are used for ISAR imaging, have suffered from high computational cost and poor imaging quality under a low signal to noise ratio (SNR) condition. This paper proposes a fast decoupled ISAR imaging method by exploiting the inherent structural sparse information of the targets. Firstly, the ISAR imaging problem is decoupled into two sub-problems. One is range direction imaging and the other is azimuth direction focusing. Secondly, an efficient two-stage SR method is proposed to obtain higher resolution range profiles by using jointly sparse information. Finally, the residual linear Bregman iteration via fast Fourier transforms (RLBI-FFT) is proposed to perform the azimuth focusing on low SNR efficiently. Theoretical analysis and simulation results show that the proposed method has better performence to efficiently implement higher-resolution ISAR imaging under the low SNR condition.

关键词： sparse recovery inverse synthetic aperture radar (ISAR) imaging high-resolution signal to noise ratio (SNR) structural sparse information

Nonadiabatic Effects of Atomic Coherence on Laser Intensity Fluctuations in Electromagnetically Induced Transparency

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Chinese Physics Letters 2011年第7期28卷 179-182页

作者： XU Qing hu xiang-Ming College of Physical Science and Technology Huazhong Normal UniversityWuhan 430079 College of Physical Science and Technology Huanggang Normal UniversityHuanggang 438000

In an electromagnetically induced transparency system,the atoms have long-lived coherence compared to the cavity lifetime and interact nonadiabatically with the laser *** show that the high frequency fluctuations of both the intensities and the intensity difference can be squeezed below the shot noise limit due to the nonadiabatic *** noise squeezing can be used to enhance the precision in the short time measurements based on the intensities or the intensity difference.

关键词： adiabatic lifetime transparency

FORMATION LAW OF PHASES IN ULTRAFINE POWDERS OF Al-Cu ALLOY PREPARED BY GAS EVAPORATION PROCESS

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中国有色金属学会会刊：英文版 1999年第2期9卷 128-133页

作者： Yan, Hongge Chen, Zhenhua hu, xiang huang, Peiyun Central South Univ of Technology Changsha China

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关键词： gas evaporationvapor condensationultrafine powdersalloy powder

Squeezed Quantum-Beat Laser Without Inversion

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Chinese Physics Letters 1998年第12期15卷 880-882页

作者： hu xiang-ming PENG Jin-sheng Department of Physics Huazhong Normal UniversityWuhan 430079

A quantum-beat laser without inversion is proposed for producing two-mode *** the dressed-atom-dressed-mode approach,the master equation is derived and the variances in the sum mode intensity and in the relative amplitude and phase are *** the laser is operated well above threshold,the intensity fluctuations in the sum mode are reduced below the shot noise limit with an optimum Mandel parameter *** the same time,the fluctuations in the relative amplitude and phase are retained at their vaccum noise levels.

关键词： Inversion limit optimum

Effects of Pump Phase Noise on the Linewidth of a Λ-Laser Without Inversion: Linewidth Reduction

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Chinese Physics Letters 1998年第8期15卷 571-573页

作者： hu xiang-ming PENG Jin-sheng Department of Physics Huazhong Normal UniversityWuhan 430079

The effects of the pump phase fluctuation on aΛ-laser with and without inversion are *** is shown that the pump phase fluctuation can reduce the linewidth of the laser without *** is also shown that,when the system exhibits a transition from lasing without inversion to lasing with inversion,the laser linewidth can still be reduced.

关键词： pump laser lasing

Effects of Detunings on Dynamically Induced Irreversibility in Coherently Driven Systems

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Chinese Physics Letters 2000年第3期17卷 200-202页

作者： hu xiang-Ming PENG Jin-Sheng Department of Physics Huazhong Normal UniversityWuhan 430079

Effects of detunings on dynamically induced irreversibility is studied for coherently driven V systems in which there is no conventional source of irreversible population *** atomic barium(γ1/γ2=400>>1,whereγ1 andγ2 are the rates of the spontaneous decay from the excited states 6s6p^(1)P_(1)and 6s6p^(3)P_(1)to the ground state 6s^(2)^(1)S_(0),respectively),the strong irreversibility is found to lead to a maximum inversion of 0.77[only 0.1 in ***.71(1993)4311].The maximum population inversion requires relatively strong Gelds coupled respectively to two transitions,a disparity in two atomic decay rates,and the atom-field detunings of opposite ***,it is also shown that even in the cases where two detunings have the same sign,or where two decay rates are equal,population inversion takes place.

关键词： decay irreversible excited