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Magnetic Properties of Ferromagnetic Double Layers with Ferrimagnetic Interlayer Coupling at Zero Temperature

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Communications in Theoretical Physics 2009年第2期51卷 349-352页

作者： JIANG Wei ZHU cheng-bo WANG Wei zhang Fan College of Sciences Shenyang University of Technology Shenyang 110023 China

Spin-wave theory is used to study magnetic properties of ferromagnetic double layers with a ferrimagnetic interlayer coupling at zero temperature. The spin-wave spectra and four sublattices magnetizations and internal energy are calculated by employing retarded Green function technique. The sublattice magnetizations at ground state are smaller than their classical values, owing to the zero-point quantum fluctuations of the spins.

关键词： spin-wave theory ferromagnetic double layers zero-point quantum fluctuation ferrimagnetic interlay coupling

Deflagration and detonation induced by shock wave focusing at different Mach numbers

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Chinese Journal of Aeronautics 2024年第2期37卷 249-258页

作者： Zezhong YANG Jun cheng bo zhang School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

Shock wave focusing is an effective way to create a hot spot or a high-pressure and hightemperature region at a certain place,showing its unique usage in detonation initiation,which is beneficial for the development of detonation-based *** flame propagation behavior after the autoignition induced by shock wave focusing is crucial to the formation and self-sustaining of the detonation *** this study,wedge reflectors with two different angles(60°and 90°)and a planar reflector are employed,and the Mach number of incident shock waves ranging from 2.0 to 2.8 is utilized to trigger different flame propagation *** pressure transducers and the high-speed schlieren imaging system are both employed to investigate the shock-shock collision and ignition *** results reveal a total of four flame propagation modes:deflagration,DDT(Deflagration-to-Detonation Transition),unsteady detonation,and direct *** detonation wave formed in the DDT and unsteady detonation mode is only approximately 75%-85%of the Chapman-Jouguet(C-J)speed;meanwhile,the directly induced detonation wave speed is close to the C-J *** waves,which are strong evidence for the existence of detonation waves,are discovered in *** usage of wedge reflectors significantly reduces the initial pressure difference ratio needed for direct detonation *** also provide a practical method for differentiating between detonation and deflagration modes,which involves contrasting the speed of the reflected shock wave with the speed of the theoretically nonreactive reflected shock *** findings should serve as a reference for the detonation initiation technique in advanced detonation propulsion engines.

关键词： Deflagration Detonation Hydrogen Ignition Shock wave focusing

Synthesis,liquid crystalline and luminescent properties of trimeric phenylenevinylene with end-groups of(R)-(+)-2-methylbutyric acid ester

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Chinese Chemical Letters 2009年第12期20卷 1423-1426页

作者： cheng bo zhang Ying Li Wen Ke Liu Hai Quan zhang Huai Yang Qing Shan Li Guang Zhong Xing State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China Department of Materials Physics and Chemistry School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The trimeric phenylenevinylene with the symmetrical chiral end-groups （ChTPV） was synthesized. The liquid crystalline and luminescent properties of the ChTPV have been studied by differential scanning calorimetry （DSC）, polarized optical microscopy （POM）, absorption and photoluminescence spectra. The results indicated that the ChTPV exhibits mesophase over a wide temperature range and a typical optical texture of smectic phase. In contrast with the spectra of the solution, that of the film showed blue-shift in maximal absorption and red-shift in maximal emission due to H-type aggregation with parallel alignment of the TPV transition dipole moment.

关键词： Trimeric phenylenevinylene Chiral Synthesis Liquid crystalline Luminescence H-type aggregation

Friction as energy dissipation process associated with superlubricity of solids

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Friction 2024年第9期12卷 2083-2088页

作者： bo zhang Saga University Saga-shi 840-8502Japan

The paper shows that work in a quantum system is quantized with energy;the quantum work is equivalent to the highest eigenenergy(the Debye energy)of the system and the superlubricity of solids is derived from the quantum *** prerequisite for the superlubricity is that the lateral force at contact surfaces in sliding is less than the Debye force so that the phonon of the solids is not excited.

关键词： superlubricity phonon friction Plank law Debye frequency

Hepatic inflammatory myofibroblastic tumor: A case report

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World Journal of Clinical Cases 2023年第18期11卷 4318-4325页

作者： Meng Tong bo-cheng zhang Fei-Yu Jia Jing Wang Jing-Hua Liu Department of General Surgery Jinzhou Medical UniversityJinzhou 121001Liaoning ProvinceChina Graduate Management Office Education and Teaching DepartmentLinyi People’s HospitalLinyi 276000Shandong ProvinceChina Department of Radiology Linyi People’s HospitalLinyi 276000Shandong ProvinceChina Department of Hepatobiliary Surgery and Minimally Invasive Institute of Digestive Surgery and Prof.Cai’s Laboratory Linyi People’s HospitalLinyi 276000Shandong ProvinceChina

BACKGROUND Hepatic inflammatory myofibroblastic tumor(HIMT)is a rare type of hepatic *** is always misdiagnosed and mistreated because it is primarily found with no obvious specific manifestation,and its imaging findings are *** SUMMARY Here,we report a case of HIMT that was initially diagnosed as liver malignancy but was confirmed as HIMT by histopathology after ***,HIMTs are infiltrated with plasma cells and stain positively for anaplastic lymphoma kinase on immunohistochemistry as well as for some other *** HIMT can be treated with single nonsteroidal anti-inflammatory drugs and without surgery when it is diagnosed *** the etiology of HIMT is unknown and the diagnosis is difficult,the pathogenesis and clinical process need to be further studied.

关键词： Hepatic inflammatory myofibroblastic tumor Laparoscopic hepatectomy Anaplastic lymphoma kinase Liver neoplasms Case report

Chemical modification of barite for improving the performance of weighting materials for water-based drilling fluids

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Petroleum Science 2024年第1期21卷 551-566页

作者： Li-Li Yang Ze-Yu Liu Shi-bo Wang Xian-bo He Guan-cheng Jiang Jie zhang MOE Key Laboratory of Petroleum Engineering State Key Laboratory of Petroleum Resources and ProspectingChina University of Petroleum(Beijing)Changping DistrictBeijing102249China MOE Key CNPC Drilling Research Institute Changping DistrictBeijing102206China

With increasing drilling depth and large dosage of weighting materials,drilling fluids with high solid content are characterized by poor stability,high viscosity,large water loss,and thick mud cake,easier leading to reservoir damage and wellbore *** this paper,micronized barite(MB)was modified(mMB)by grafting with hydrophilic polymer onto the surface through the free radical polymerization to displace conventional API barite *** suspension stability of water-based drilling fluids(WBDFs)weighted with API barite:mMB=2:1 in 600 g was significantly enhanced compared with that with API barite/WBDFs,exhibiting the static sag factor within 0.54 and the whole stability index of *** viscosity and yield point reached the minimum,with a reduction of more than 40%compared with API barite only at the same *** multi-stage filling and dense accumulation of weighting materials and clays,filtration loss was decreased,mud cake quality was improved,and simultaneously it had great reservoir protection performance,and the permeability recovery rate reached 87%.In addition,it also effectively improved the lubricity of *** sticking coefficient of mud cake was reduced by 53.4%,and the friction coefficient was ***,mMB can serve as a versatile additive to control the density,rheology,filtration,and stability of WBDFs weighted with API barite,thus regulating comprehensive performance and achieving reservoir protection *** work opened up a new path for the productive drilling of extremely deep and intricate wells by providing an efficient method for managing the performance of high-density WBDFs.

关键词： Drilling fluids Weighting materials Filtration control Reservoir protection Stability property

Measurements of electronic properties of the Miyun 50m Radio Telescope

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Chinese Journal of Astronomy and Astrophysics 2009年第3期9卷 367-376页

作者： Xi-Zhen zhang Xin-Ying Zhu De-Qing Kong Lei Zheng cheng Yao Hong-bo zhang Yan Su Ting-Yi Piao National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Measurement results of some properties of the Miyun 50 m radio telescope （MRT50） of the National Astronomical Observatories, such as pointing calibration, antenna beams, system noise temperature, gain and gain variations with elevation are introduced. By using a new de-convolution technique developed by our group, the broadening effect on measured beams caused by the width of art extended radio source has been removed so that we obtained higher accuracy on the measurements of MRT50 beams.

关键词： instrument telescope - antenna - method

In vitro corrosion resistance of a Ta2O5 nanofilm on MAO coated magnesium alloy AZ31 by atomic layer deposition

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Bioactive Materials 2020年第1期5卷 34-43页

作者： Chang-Yang Li Chi Yu Rong-Chang Zeng bo-cheng zhang Lan-Yue Cui Jun Wan Yang Xia Corrosion Laboratory for Light Metals College of Materials Science and EngineeringShandong University of Science and TechnologyQingdao266590China Jiaxing Microelectronics Engineering Center Chinese Academy of SciencesJiaxing314022China Institute of Microelectronics Chinese Academy of SciencesBeijing100029China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450002China

Micro-arc oxidation(MAO)coating with outstanding adhesion strength to Mg alloys has attracted more and more ***,owing to the porous structure,aggressive ions easily invaded the MAO/substrate interface through the through pores,limiting long-term corrosion ***,a dense and biocompatible tantalum oxide(Ta2O5)nanofilm was deposited on MAO coated Mg alloy AZ31 through atomic layer deposition(ALD)technique to seal the micropores and regulate the degradation *** micrography,chemical compositions and crystallographic structure were characterized using FE-SEM,EDS,XPS and *** corrosion resistance of all samples was evaluated through electrochemical and hydrogen evolution *** revealed that the Ta2O5 film mainly existed in the form of ***,uniform deposition of Ta2O5 film and effective sealing of micropores and microcracks in MAO coating were *** current density(icorr)of the composite coating decreased three orders of magnitude than that of the substrate and MAO coating,improving corrosion ***,the formation and corrosion resistance mechanisms of the composite coating were proposed.

关键词： Magnesium alloys Micro-arc oxidation Atomic layer deposition Coatings

Multi-distortion suppression for neutron radiographic images based on generative adversarial network

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Nuclear Science and Techniques 2024年第4期35卷 176-188页

作者： cheng-bo Meng Wang-Wei Zhu Zhen zhang Zi-Tong Wang Chen-Yi Zhao Shuang Qiao Tian zhang School of Physics Northeast Normal UniversityChangchun 130024China

Neutron radiography is a crucial nondestructive testing technology widely used in the aerospace,military,and nuclear ***,because of the physical limitations of neutron sources and collimators,the resulting neutron radiographic images inevitably exhibit multiple distortions,including noise,geometric unsharpness,and white ***,these distortions are particularly significant in compact neutron radiography systems with low neutron ***,in this study,we devised a multi-distortion suppression network that employs a modified generative adversarial network to improve the quality of degraded neutron radiographic *** neutron radiographic image datasets with various types and levels of distortion were built for the first time as multi-distortion suppression ***,the coordinate attention mechanism was incorporated into the backbone network to augment the capability of the proposed network to learn the abstract relationship between ideally clear and degraded *** experiments were performed;the results show that the proposed method can effectively suppress multiple distortions in real neutron radiographic images and achieve state-of-theart perceptual visual quality,thus demonstrating its application potential in neutron radiography.

关键词： Neutron radiography Multi-distortion suppression Generative adversarial network Coordinate attention mechanism