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Characteristics　of　tectonic　deformation　field　about　strike－slip　earthquake－generating　structure　in　the　Chinese　mainland

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Acta Seismologica Sinica(English Edition) 1995年第2期8卷 175-184页

作者：环文林张晓东宋昭仪 1. institute of Geophysics SSB 100081 Beijing China

This paper is the second one of the serial papers about the study on strike slip earthquake-generating structure in the interior of the Chinese mainland. In the first part of the paper,the deformation field model of strike slip earthquake-generating structure is *** puts forward that a strike slip fault is not dominated by horizontal displacement everywhere along the whole belt,its deformation characteristics is different from section to section, only the central main body shows strike slip feature,the two ends take vertical deformation as the major *** the second part,through the discussion of deformation field characteristics about strike slip earthquake-generating fault for several clearly investigated large earthquakes with M≥7.0 that occurred recently in the Chinese mainland, it is further confirmed that although each of these earthquakes possesses its own complicated features,they also share the common feature that the earthquake-generating faults have the deformation field characteristics similar to those of the above-mentioned strike slip earthquake-generating structure.

关键词： crustal deformation research strike-slip fault,dislocation,displacement

An effective DOA method via virtual array transformation

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Science China(Technological Sciences) 2001年第1期44卷 75-82页

作者：王永良陈辉万山虎 1. Wuhan Radar institute 430010 Wuhan China

A new DOA estimation method is presented for the virtual arraytransformation and the improved spatial smoothing algorithm. The new method not only overcomes the weakness of the ambiguity of DOA estimation of arbitrary array, but also improves the abilities of resolution and de-correlation. It is proven to be effective by theoretical analyses and computer simulations. What is more, the method can improve the estimation and resolution of DOA under the condition of sparse practical array.

关键词： DOA method virtual array transformation

Thermochemical sulphate reduction and Huayuan lead-zinc ore deposit in Hunan, China

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Science China Earth Sciences 2001年第5期44卷 414-425页

作者：刘文钧郑荣才 1. Chengdu institute of Technology 610059 Chengdu China

In recent years, some arguments with regard to the organicmineralization of MVT lead-zinc ore deposit are focused on the thermochemical sulphate reduction in the presence of organic matter. Based on the research into the organic geochemistry and C, O, S isotopes of mineralized host rocks, mineral gas fluid inclusion and solid bitumen from Huayuan (W. Hunan, China) lead-zinc ore deposit formed in the algal limestones of Qingxudong formation, Lower Cambrian, the authors consider that a lot of organic matter occurred and participated in mineralization. The organic matter from different sources participated in the mineralization with two main forms: thermochemical sul-phate reduction and thermal degradation which supplied abundant H2S for the precipitation.

关键词： MVT deposit organic mineralization thermochemical reduction thermal degradation

Research on the influence of machining introduced sub-surface defects and residue stress upon the mechanical properties of single crystal copper

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Science China(Technological Sciences) 2010年第12期53卷 3161-3167页

作者： CHEN MingJun, XIAO GaoBo, CHEN JiaXuan & WU ChunYa Harbin institute of Technology, Harbin 1.0001. China 1. Harbin institute of Technology Harbin 150001 China

Large scale molecular dynamics simulations of nanomachining and stretching of single crystal copper are performed to analyze the machining process’ influence on the material’s mechanical properties. The simulation results show that the machining process will introduce interfacial defects inside the specimen and enhance the compressive stress beneath the surface. Gener- ally speaking, interfacial defects lead to the decrease of the strength limit, while residue compressive stress can enhance the elastic limit and even the strength limit. Various machining parameters are adopted to investigate their influence on the me- chanical behavior of machined specimen. Lower cutting speed and smaller cutting depth lead to less defects and greater residue compressive stress, which brings about better mechanical properties. The elastic limit increases by 36.8% under the cutting depth of 0.73 nm and decreases by 21.1. under the cutting depth of 1.46 nm. The strength limit increases by 7.7% under the cutting speed of 1.0 m/s and decreases by 28.2% under the cutting speed of 300 m/s.

关键词： nanomachining deformation residue stress molecular dynamics dislocations

Construction of a trivalent candidate vaccine against Shigella species with DNA recombination

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Science China(Life Sciences) 2002年第1期45卷 10-20页

作者：王恒樑廖翔苏国富冯尔玲金明黄翠芬林云黄留玉 1. Beijing institute of Biotechnology 100071 Beijing China

In this work asd gene of Shigella flexneri 2a strain T32 was replaced by Vibrio cholerae toxin B subunit (ctxB) gene with DNA recombination in vivo and in vitro. The resulting derivative of T32, designed as FWL01. could stably express CtxB, but its growth in LB medium depended on the presence of diaminopimelic acid (DAP). Then form I plasmid of Shigella sonnei strain S7 was labeled with strain T32 asd gene and mobilized into FWL01. Thus a trivalent candidate oral vaccine strain, designed as FSW01. was constructed. In this candidate strain, a balanced-lethal system was constituted between the host strain and the form I plasmid expressing S. sonnei O antigen. Therefore the candidate strain can express stably not only its own O antigen but also CtxB and O antigen of S. sonnei in the absence of any antibiotic. Experiments showed that FSW01.did not invade HeLa cells or cause keratoconjunctivitis in guinea pigs. However, rabbits immunized FSW01.can elicit significant immune responses. In mice and rhesus monkey models, vaccinated animals were protected against the challenges of wild S. flexneri 2a strain 2457T and S. sonnei strain S9.

关键词： Shigella spp., ctxB gene, balanced-lethal system, vaccine.

Status quo and future prospects of artificial neural network from the perspective of gastroenterologists

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World Journal of Gastroenterology 2021年第21期27卷 2681-2709页

作者： Bo Cao Ke-Cheng Zhang Bo Wei Lin Chen Department of general {1.&institute of general {1. Chinese People’s Liberation Army General HospitalBeijing 100853China

Artificial neural networks(ANNs)are one of the primary types of artificial intelligence and have been rapidly developed and used in many *** recent years,there has been a sharp increase in research concerning ANNs in gastrointestinal(GI)*** state-of-the-art technique exhibits excellent performance in diagnosis,prognostic prediction,and *** between ANNs and GI experts suggest that efficiency and accuracy might be compatible in virtue of technique ***,the shortcomings of ANNs are not negligible and may induce alterations in many aspects of medical *** this review,we introduce basic knowledge about ANNs and summarize the current achievements of ANNs in GI diseases from the perspective of *** limitations and future directions are also proposed to optimize ANN’s clinical *** consideration of barriers to interdisciplinary knowledge,sophisticated concepts are discussed using plain words and metaphors to make this review more easily understood by medical practitioners and the general public.

关键词： Artificial neural network Gastrointestinal disease Diagnosis Treatment Prognosis Endoscopy

Specific staining and precise killing of cancer cells through fusion of pharmaceutical chemistry and π-bridge effect design philosophy

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Science China Chemistry 2025年

作者： Qiong Liu Qiyun Deng Changxu Zhu Kongqi Chen Lidan Chen Zhaohui Sun Ben Zhong Tang Zhiming Wang AIE institute Center for Aggregation-Induced Emission State Key Laboratory of Luminescent Materials and Devices Key Laboratory of Luminescence from Molecular Aggregates of Guangdong Province South China University of Technology Department of Laboratory Medicine general Hospital of Southern Theater Command School of Life Sciences The Chinese University of Hong Kong Shenzhen institute of Aggregate Science and Technology School of Science and Engineering The Chinese University of Hong Kong HKUST-Shenzhen Research institute

The development of an advanced phototheranostic platform that combines imaging and therapy in a single agent is an appealing yet challenging *** this study,we successfully constructed three novel fluorescent probes by leveraging pharmaceutical chemistry and the design philosophy of theπ-bridge *** a systematic comparative analysis of their fluorescence properties,water solubility,molecular conformation,and electrostatic potential,we revealed the fundamental principles governing the optical behavior and biological selectivity of these ***,the probe TPhIQ-CNTh demonstrated extended fluorescence in the near-infrared region,a significant aggregation-induced emission (AIE) effect,and the ability to distinguish tumor cells from normal ***,it efficiently generated reactive oxygen species (ROS) and specifically labeled lipid droplets,enabling the precise staining and killing of cancer *** study presents a practical strategy for designing precise tumor treatments that integrate efficient imaging-guided photodynamic therapy (PDT) by harnessing the unique properties of AIE materials.

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Structures and aromaticity of the planar Al_2P_2^(n-) (n=1.4) clusters

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Science China Chemistry 2009年第12期52卷 2237-2242页

作者： XU WenGuo,ZHANG YuanChun & ZHAI Lei institute of Chemical Physics,Beijing institute of Technology,Beijing 1.0081.China 1. institute of Chemical Physics Beijing Institute of Technology Beijing 100081 China

Clusters Al2P2n-(n = 1.4) were theoretically investigated using density functional theory (DFT) methods at the B3LYP/6-31.+G* and B3PW91.6-31.+G* levels of theory. The calculated results showed that the planar structure (D2h symmetry) of Al2P2n-(n = 1.4) species was the global minimum. And the negative nucleus-independent chemical shift (NICS) value of Al2P2n-(n = 1.4) species indicated the existence of a ring current in the planar structure (D2h symmetry). A detailed molecular orbital (MO) analysis revealed that the planar structures (D2h symmetry) had π aromaticity,which further exhibited the strongly aromatic character for Al2P2n-(n = 1.4) species.

关键词： DFT calculation geometric structure nucleus-independent chemical shift molecular orbital

NUMERICAL SIMULATION OF THE FLOW FIELD IN A THERMAL PLASMA REACTOR

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Applied Mathematics and Mechanics(English Edition) 1990年第12期11卷 1167-1170页

作者：李国彦 1. Kunming institute of Technology Kunming

A numerical simulation is presented for a thermal plasma reactor with particle-trajectory model in this paper. Turbulance is considered by using simple SGS model. The governing equations are solved by means of the algorithm of SIMPLER. The calculated results give the velocity and the temperature fields within plasma reactor, and the trajectories of the injected particles.

关键词： plasma flow field numerical simulation turbulence model