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Journal of Iron and Steel Research International 2014年第11期21卷 1016-1021页

作者： Hui-bin WU Jin-ming LIANG Di TANG Xiao-tong LIU Peng-cheng ZHANG yuan-jie yue National Engineering Research Center of Advanced Rolling Technology University of Science and Technology Beijing

Corrosion behavior of low-alloy steel was investigated in simulated cargo oil tank （COT） bottom plate service environment （10% NaCl solution, pH = 0.85）. The corrosion behavior of inclusion was studied by in-situ scanning electron microscopy （SEM） and energy dispersive spectroscopy （EDS）. It was found that pitting corrosion was inclined to occur around the place where inclusions exist. After initial corrosion, an area of 10-20μm in diameter was formed as a cireinate cathode around the edge of inclusion. MnS inclusion dissolved in the simulated COT corrosion solution before low-alloy steel matrix, and pitting was formed at the place where MnS dissolved. TiO2 inclusion dissolved in the simulated COT corrosion solution after low alloy steel matrix, and pitting was formed at the place where steel matrix dissolved. The corrosion tended to occur at the area where the curvature radius of inclusion is smaller. The size of round TiO2 inclusions had little influence on corrosion behavior in this certain environment.

关键词： cargo oil tank corrosion behavior low alloy steel pitting mechanism inclusion

Simutaneous radar imaging and velocity measuring with step frequency waveforms

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Journal of Systems Engineering and Electronics 2009年第4期20卷 741-747页

作者： yuan Haotian Wen Shuliang cheng Zhen Beijing Inst. of Radio Measurement Beijing 100854 P. R. China

The principle and method of both radar target imaging and velocity measurement simultaneously based on step frequency waveforms is presented. Velocity compensation is necessary in order to obtain the good High resolution range profile since this waveform is greatly sensitive to the Doppler shift. The velocity measurement performance of the four styles is analyzed with two pulse trains consisted of positive and negative step frequency waveforms. The velocity of targets can be estimated first coarsely by using the pulse trains with positive-positive step frequency combination, and then fine by positive-negative combination. Simulation results indicate that the method can accomplish the accurate estimation of the velocity with efficient computation and good anti-noise performance and obtain the good HRRP simultaneously.

关键词： high resolution radar step frequency waveform velocity measuring high resolution range profile.

Effect of strain-gradients of surface micro-beams on frequency-shift of a quartz crystal resonator under thickness-shear vibrations

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Acta Mechanica Sinica 2015年第5期31卷 647-652页

作者： Ling-cheng Kong yuan-Tai Hu Department of Mechanics Huazhong University of Science and Technology

With introduction of the first-order strain-gradient of surface micro-beams into the energy density function,we developed a two-dimensional dynamic model for a compound quartz crystal resonator（QCR） system,consisting of a QCR and surface micro-beam *** frequency shift that was induced by micro-beams with consideration of strain-gradients is discussed in detail and some useful results are obtained,which have important significance in resonator design and applications.

关键词： Micro-beams Strain-gradient Quartz crystal resonator Frequency shift

Validity ranges of interfacial wave theories in a two-layer fluid system

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Acta Mechanica Sinica 2007年第6期23卷 597-607页

作者： Yutang yuan Jiachun Li Youliang cheng Division of Engineering Sciences Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Department of Dynamic Engineering North China Electric Power University Baoding 071003 China

In the present paper, we endeavor to accomplish a diagram, which demarcates the validity ranges for interfacial wave theories in a two-layer system, to meet the needs of design in ocean engineering. On the basis of the available solutions of periodic and solitary waves, we propose a guideline as principle to identify the validity regions of the interfacial wave theories in terms of wave period T, wave height H, upper layer thickness dl, and lower layer thick-ness d2, instead of only one parameter-water depth d as in the water surface wave circumstance. The diagram proposed here happens to be Le Mehaute＇s plot for free surface waves if water depth ratio r= d1/d2 approaches to infinity and the upper layer water density p1 to zero. On the contrary, the diagram for water surface waves can be used for two-layer interfacial waves if gravity acceleration g in it is replaced by the reduced gravity defined in this study under the condition of σ=（P2 - Pl）/P2 → 1.0 and r 〉 1.0. In the end, several figures of the validity ranges for various interfacial wavetheories in the two-layer fluid are given and compared with the results for surface waves.

关键词： Validity ranges Two-layer fluid Interfacial waves Interfacial solitary waves Ursell number

Uncoupled PID Control of Coupled Multi-Agent Nonlinear Uncertain Systems

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Journal of Systems Science & Complexity 2018年第1期31卷 4-21页

作者： yuan Shuo ZHAO cheng GUO Lei LSC Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China. School of Mathematical Sciences University of Chinese Academy of Sciences Beijing 100049 China LSC Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

In this paper, PID（proportional-integral-derivative） controllers will be designed to solve the tracking problem for a class of coupled multi-agent systems, where each agent is described by a second-order high-dimensional nonlinear uncertain dynamical system, which only has access to its own tracking error information and does not need to communicate with others. This paper will show that a 3-dimensional manifold can be constructed based on the information about the Lipschitz constants of the system nonlinear dynamics, such that whenever the three parameters of each PID controller are chosen from the manifold, the whole multi-agent system can be stabilized globally and the tracking error of each agent approaches to zero asymptotically. For a class of coupled first-order multi-agent nonlinear uncertain systems, a PI controller will be designed to stabilize the whole system.

关键词： Coupled multi-agent system global stability Lipschitz condition nonlinear uncertain dynamics PID controller

Nucleotide excision repair pathway gene polymorphisms are associated with risk and prognosis of colorectal cancer

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World Journal of Gastroenterology 2020年第3期26卷 307-323页

作者： Yan-Ke Li Qian Xu Li-Ping Sun yue-Hua Gong Jing-Jing Jing cheng-Zhong Xing yuan yuan Tumor Etiology and Screening Department of Cancer Institute and General Surgery Key Laboratory of Cancer Etiology and Prevention of Liaoning Education DepartmentKey Laboratory of GI Cancer Etiology and Prevention of Liaoning Provincethe First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Department of Anorectal Surgery the First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina

BACKGROUND Single nucleotide polymorphisms(SNPs)are universally present in nucleotide excision repair(NER)pathway genes,which could make impacts on colorectal carcinogenesis and *** To explore the association of all tagSNPs in NER pathway genes with colorectal cancer(CRC)risk and prognosis in a northern Chinese population by a two-stage case-control design composed of a discovery and validation *** Genotyping for NER SNPs was performed using kompetitive allele specific *** the discovery stage,39 tagSNPs in eight genes were genotyped in 368 subjects,including 184 CRC cases and 184 individual-matched *** the validation stage,13 SNPs in six genes were analyzed in a total of 1712 subjects,including 854 CRC cases and 858 CRC-free *** Two SNPs(XPA rs10817938 and XPC rs2607775)were associated with an increased CRC risk in overall and stratification *** cumulative and interaction effects were also demonstrated in the studied SNPs on CRC *** two SNPs(ERCC2 rs1052555 and ERCC5 rs2228959)were newly found to be associated with a poor overall survival of CRC *** Our findings suggest novel SNPs in NER pathway genes that can be predictive for CRC risk and prognosis in a large-scale Chinese *** present study has referential values for the identification of all-round NER-based genetic biomarkers in predicting the susceptibility and clinical outcome of CRC.

关键词： Nucleotide excision repair Polymorphism Colorectal cancer Susceptibility Prognosis

Mapping impervious surfaces with a hierarchical spectral mixture analysis incorporating endmember spatial distribution

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Geo-Spatial Information Science 2022年第4期25卷 550-567页

作者： Zhenfeng Shao yuan Zhang cheng Zhang Xiao Huang Tao cheng State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhanChina Department of Geosciences University of ArkansasFayettevilleARUSA

Impervious surface mapping is essential for urban environmental *** Mixture Analysis(SMA)and its extensions are widely employed in impervious surface estimation from medium-resolution *** SMA,inappropriate endmember combinations and inadequate endmember classes have been recognized as the primary reasons for estimation ***,the spectral-only SMA,without considering urban spatial distribution,fails to consider spectral variability in an adequate *** lack of endmember class diversity and their spatial variations lead to over/*** mitigate these issues,this study integrates a hierarchical strategy and spatially varied endmember spectra to map impervious surface abundance,taking Wuhan and Wuzhou as two study ***,the piecewise convex multiple-model endmember detection algorithm is applied to automatically hierarch-ize images into three regions,and distinct endmember combinations are independently developed in each ***,spatially varied endmember spectra are synthesized through neighboring spectra using the distance-based *** analysis indicates that the proposed method achieves better performance than Hierarchical SMA and Fixed Four-endmembers SMA in terms of MAE,SE,and *** analysis suggests that the hierarch-ical strategy can expand endmember class types and considerably improve the performance for the study areas in general,specifically in less developed ***,we find that spatially varied endmember spectra facilitate the reduction of heterogeneous surface material variations and achieve the improved performance in developed areas.

关键词： Impervious surface Spectral Mixture Analysis(SMA) hierarchical strategy endmember class spatially varied endmember spectra

Efficacy and safety of Xinfeng capsule in the treatment of osteoarthritis:a multicenter, randomized, double-blinded, controlled trial

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Journal of Traditional Chinese Medicine 2020年第2期40卷 284-295页

作者： Liu Jian Wang yuan Sun yue Huang Chuanbing Chen Xi Zhang Wandong He Liyun James cheng-Chung Wei Department of Rheumatism Immunity The First Affiliated HospitalAnhui University of Chinese MedicineHefei 230031China the Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical SciencesBeijing 100700China Division of Allergy Immunology and RheumatologyChung Shan Medical University HospitalInstitute of MedicineChung Shan Medical UniversityGraduate Institute of Integrated MedicineChina Medical UniversityTaichungTaiwan China

OBJECTIVE: To evaluate the efficacy and safety of Xinfeng capsule(XFC) in patients with osteoarthritis(OA).METHODS: This was a multicenter, double-blinded,randomized, controlled, clinical trial. Patients with OA were assigned to the XFC group [treated with XFC and a glucosamine(GS) placebo, n = 129] or the GS group(treated with GS and an XFC placebo,n = 126). Both groups were treated for 4 weeks. The primary endpoint was the difference between the two groups in the Western Ontario and Mc Master Universities OA(WOMAC) index total score at 4 th week. The secondary endpoints were the visual analogue scale for pain, Lequesne index, function influence index rating, quality of life as assessed by the Short Form-36, erythrocyte sedimentation rate,and C-reactive protein concentration at baseline and at second week and 4 th week. Bone mineral density were checked by X ray absorptiometry at baseline and 4 th ***: After 4 weeks of treatment, all patients in both groups showed similar significant improvements compared with baseline. There were no significant differences between groups regarding pain relief, bilateral femoral bone mineral density, and laboratory indices such as erythrocyte sedimentation rate and C-reactive protein *** groups had a significantly lower function influence index rating score and curative effect for each sign/symptom in week 4 than in week 0, and these changes did not significantly differ between groups. XFC was superior to GS in improving the WOMAC index total score, WOMAC scores for function and stiffness, integrated symptoms, physiological function, energy, emotional function, mental health, and health changes. Fourteen adverse reactions were reported, and the incidence of adverse reactions did not significantly differ between groups. The most common adverse reactions were hepatic impairment, kidney functional damage,gastrectasia, and facial skin allergy. The types of adverse reactions did not differ between ***

关键词： Osteoarthritis Glucosamine Quality of life Treatment outcome Randomized controlled trial Xinfeng capsule

Silicone-covered biodegradable magnesium stent for treating benign esophageal stricture in a rabbit model

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World Journal of Gastroenterology 2019年第25期25卷 3207-3217页

作者： Kai Yang Jun Cao Tian-Wen yuan yue-Qi Zhu Bi Zhou Ying-Sheng cheng Department of Radiological Intervention Shanghai Sixth People's Hospital East Campus Affiliated to Shanghai University of Medicine&Health SciencesShanghai 201306China Department of Radiological Intervention Shanghai Sixth People's Hospital East Campus Affiliated to Shanghai Jiao Tong UniversityShanghai 201306China Department of Tumor Intervention Dahua HospitalShanghai 200237China Department of Radiological Intervention Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong UniversityShanghai 200233China

BACKGROUND Stent insertion can effective alleviate the symptoms of benign esophageal strictures(BES).Magnesium alloy stents are a good candidate because of biological safety,but show a poor corrosion resistance and a quick loss of mechanical support in *** To test the therapeutic and adverse effects of a silicone-covered magnesium alloy biodegradable esophageal *** Fifteen rabbits underwent silicone-covered biodegradable magnesium stent insertion into the benign esophageal stricture under fluoroscopic guidance(stent group).The wall reconstruction and tissue reaction of stenotic esophagus in the stent group were compared with those of six esophageal stricture models(control group).Esophagography was performed at 1,2,and 3 ***,six,and five rabbits in the stent group and two rabbits in the control groups were euthanized,respectively,at each time point for histological *** All stent insertions were well *** esophageal diameters at immediately,1,2 and 3 wk were 9.8±0.3 mm,9.7±0.7 mm,9.4±0.8 mm,and 9.2±0.5 mm,respectively(vs 4.9±0.3 mm before stent insertion;P0.05).CONCLUSION Esophageal silicone-covered biodegradable magnesium stent insertion is feasible for BES without causing severe injury or tissue *** study suggests that insertion of silicone-covered magnesium esophageal stent is a promising approach for treating BES.

关键词： Benign esophageal stricture Biodegradable stent Magnesium Silicone membrane

Accreting CO material onto ONe white dwarfs towards accretion-induced collapse

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Research in Astronomy and Astrophysics 2018年第3期18卷 121-128页

作者： cheng-yuan Wu Bo Wang Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China University of Chinese Academy of Sciences Beijing 100049 China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing 100012 China

The final outcomes of accreting ONe white dwarfs（ONe WDs） have been studied for several decades,but there are still some issues that are not resolved. Recently,some studies suggested that the deflagration of oxygen would occur for accreting ONe WDs with Chandrasekhar masses. In this paper,we aim to investigate whether ONe WDs can experience accretion-induced collapse（AIC） or explosions when their masses approach the Chandrasekhar limit. Employing the stellar evolution code Modules for Experiments in Stellar Astrophysics（MESA）,we simulate the longterm evolution of ONe WDs with accreting CO material. The ONe WDs undergo weak multicycle carbon flashes during the mass-accretion process,leading to mass increase of the WDs. We found that different initial WD masses and mass-accretion rates influence the evolution of central density and temperature. However,the central temperature cannot reach the explosive oxygen ignition temperature due to neutrino cooling. This work implies that the final outcome of accreting ONe WDs is electroncapture induced collapse rather than thermonuclear explosion.

关键词： stars evolution - binaries close - supernovae general - white dwarfs