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Field emission properties of amorphous GaN ultrathin films fabricated by pulsed laser deposition

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Science in China(Series F) 2009年第10期52卷 1947-1952页

作者： WANG FengYing WANG RuZhi zhao Wei song XueMei WANG Bo YAN hui Laboratory of Thin Film College of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

Amorphous gallium nitride （a-GaN） films with thicknesses of 5 and 300 nm are deposited on n-Si （100） substrates by pulsed laser deposition （PLD）, and their field emission （FE） properties are studied. It shows that compared with thicker （300 nm） a-GaN film, better FE performance is obtained on ultrathin （5 nm） a-GaN film with a threshold field of 0.78 V/μm, which is the lowest value ever reported. Furthermore, the current density reaches 42 mA/cm2 when the applied field is 3.72 V/μm. These experimental results unambiguously confirm Binh＇s theoretical analysis （Binh et al. Phys Rev Lett, 2000, 85（4）： 864-867） that the FE performance would be prominently enhanced with the coating of an ultra-thin wide band-gap semiconductor film.

关键词： field emission amorphous gallium nitride (a-GaN) pulsed laser deposition (PLD) work function

Microstructure, thermophysical property and ablation behavior of high thermal conductivity carbon/carbon composites after heat-treatment

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Chinese Journal of Aeronautics 2020年第5期33卷 1541-1548页

作者： Xue-song LIU Qian-Gang FU hui WANG Qiang song State Key Laboratory of Solidification Processing Shannxi Province Key Laboratory of Fiber Reinforced Light Composite MaterialsNorthwestern Polytechnical UniversityXi'an 710072PR China

Uni-directional carbon/carbon composites with high thermal conductivity are suitable to supply continuous thermal protection for future reentry vehicles since they could reduce surface temperature and ablation rates simultaneously in harsh *** this work,the high thermal conductivity carbon/carbon composites were prepared by chemical vapor *** heat-treatment,both their open porosity and internal friction increase due to the fiber/matrix thermal expansion mismatch;while their thermal conductive performance become better due to more complete carbon *** raising heat-treatment temperature from 1800℃to 2450℃,the mass and linear ablation rates of C/C composites with fibers vertical to the oxyacetylene torch for 60 s decrease from 0.66 mg/s and 2.95μm/s to 0.51 mg/s and 2.05μm/s *** improved ablation resistance is resulted from the increased thermal conductivity from 282 to 508 W/(m·K)and more carbon fibers exposed to the flame during ablation,which have better oxidation resistance than those of carbon *** such ablation rates become larger for composites with fibers parallel to the flame,from 1.02 mg/s and 3.73μm/s to 1.28 mg/s and 5.0μm/s respectively since the ablation occurred more easily through gaps at the fiber/matrix interfaces,which become larger and are always exposed to the flame for this case.

关键词： Ablation Carbon/carbon composites Fiber orientation Heat treatment Thermal conductivity

An Internal Expansive Stress Model of Concrete under Sulfate Attack

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Acta Mechanica Solida Sinica 2016年第6期29卷 610-619页

作者： hui song Jiankang Chen Jinyang Jiang The Faculty of Mechanical Engineering and Mechanics Ningbo University Ningbo 315211 China State Key Laboratory of Turbulence and Complex Systems Peking University Beijing 100871 China The Faculty of Civil Engineering and Architecture Nanchang Institute of Technology Nanchang 300029 China School of Materials Science and Engineering Southeast University Nanjing 211189 China

Concrete experiences expansive deformation during sulfate attack due to internal expansive stress. Sulfate ions enter concrete pores, react with the pore solution, and produce ettringite. The production of ettringite explains the internal expansive stress that reduces the durability of concrete. In this study, the model of internal expansive stress was achieved through the Eshelby＇s theory, as well as the experimental results for concrete erosion. Numerical simulation indicated that internal expansive stress is not only determined by the water-to-cement ratio of concrete and the concentration of sulfate solution, but also affected by the relaxation time of concrete.

关键词： concrete viscous internal stress model erosion micromechanics

Extrapolation reconstruction of wind pressure fields on the claddings of high-rise buildings

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 653-666页

作者： Yehua SUN Guquan song hui LV School of Civil Engineering and Architecture Nanchang UniversityNanchang 330033China Jiangxi Institute of Economic Administrators Nanchang 330038China

Recent research about reconstruction methods mainly used the interpolation reconstruction of the fluctuating wind pressure field on the ***,to investigate wind pressure at the edge of the building,the work presented in this paper focuses on the extrapolation reconstruction of wind pressure ***,we propose an improved proper orthogonal decomposition(POD)and Kriging method with a von Karman correlation function to resolve this *** studies show that it works well for not only interpolation reconstruction but also extrapolation *** proposed method does require determination of the Hurst exponent and other parameters analysed from the original ***,the fluctuating wind fields have been characterized by the von Karman correlation function,as an a priori *** with the cubic spline method and different variogram,preliminary results suggest less time consumption and high efficiency in extrapolation reconstruction at the edge.

关键词： extrapolation reconstruction proper orthogonal decomposition Kriging method von Karman function Hurst exponent rescaled range analysis

Rare monolocular intrahepatic biliary cystadenoma: A case report

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World Journal of Clinical Cases 2021年第26期9卷 7886-7892页

作者： Chen-Hao Che Zhen-Hua zhao hui-Ming song Yuan-Yuan Zheng The First Clinical Medical School Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Radiology Shaoxing People's Hospital(Shaoxing HospitalZhejiang University School of Medicine)Shaoxing 312000Zhejiang ProvinceChina Department of Ultrasonography Shaoxing People's Hospital(Shaoxing HospitalZhejiang University School of Medicine)Shaoxing 312000Zhejiang ProvinceChina

BACKGROUND Intrahepatic biliary cystadenoma(IBC)is a rare benign hepatic tumor that is often misdiagnosed as other hepatic cystic ***,imaging examinations are required for preoperative ***-enhanced ultrasound(CEUS)has gained increasing popularity as an emerging imaging modality and it is considered the primary method for screening IBC because of its specificity of *** describe an unusual case of monolocular IBC and emphasize the performance of *** SUMMARY A 45-year-old man complained of epigastric pain lasting 1 *** had no medical history of hepatitis,liver cirrhosis or *** examination revealed a mass of approximately 6 cm in size in the upper abdomen below the subxiphoid *** marker tests found elevated CA19-9 levels(119.3 U/mL),but other laboratory tests were *** and computerized tomography revealed a round thick-walled mass measuring 83 mm×68 mm located in the left lateral lobe of the liver that lacked internal septations and manifested as a monolocular cystic *** demonstrated that in the arterial phase,the anechoic area manifested as a peripheral ring with homogeneous *** central part presented with no *** the portal phase,the enhanced portion began to subside but was still above the surrounding liver *** patient underwent left partial liver lobectomy and recovered well without tumor recurrence or ***,the results of pathological examination confirmed *** A few IBC cases present with monolocular characteristics,and the lack of intracystic septa in imaging performance cannot exclude IBC.

关键词： Intrahepatic biliary cystadenoma Monolocular Diagnosis Imaging performance Contrast-enhanced ultrasound Case report

Application of Newcastle disease virus in the treatment of colorectal cancer

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World Journal of Clinical Cases 2019年第16期7卷 2143-2154页

作者： hui song Li-Ping Zhong Jian He Yong Huang Yong-Xiang zhao National Center for International Research of Bio-targeting Theranostics Guangxi Key Laboratory of Biotargeting Theranostics Collaborative Innovation Center for Targeting Tumor Diagnosis and Therapy Guangxi Medical University

Colorectal cancer (CRC) is one of the main reasons of tumor-related deaths *** present,the main treatment is surgery,but the results are unsatisfactory,and the prognosis is *** majority of patients die due to liver or lung metastasis or *** recent years,great progress has been made in the field of tumor gene therapy,providing a new treatment for combating *** oncolytic viruses selectively replicate almost exclusively in the cytoplasm of tumor cells and do not require integration into the host genome,they are safer,more effective and more attractive as oncolytic *** disease virus (NDV) is a natural RNA oncolytic *** NDV selectively infects tumor cells,the immune response induced by NDV’s envelope protein and intracellular factors can effectively kill the tumor without affecting normal *** genetic techniques make NDV a vector for gene *** the virus by inserting various exogenous genes or using NDV in combination with immunotherapy can also improve the anti-CRC capacity of NDV,and good results have been achieved in animal models and clinical treatment *** article reviews the molecular biological characteristics and oncolytic mechanism of NDV and discusses in vitro and in vivo experiments on NDV anti-CRC capacity and clinical *** conclusion,NDV is an excellent candidate for cancer treatment,but more preclinical studies and clinical trials are needed to ensure its safety and efficacy.

关键词： Newcastle disease virus Exogenous gene Armed virus Oncolytic therapy Colorectal cancer

Residual stress of physical vapor-deposited polycrystalline multilayers

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Science China(Physics,Mechanics & Astronomy) 2015年第2期58卷 55-63页

作者： ZHANG song ZHANG hui ZHENG LiLi School of Aerospace Tsinghua University Department of Engineering Physics Tsinghua University

An extended one-dimensional stress model for the deposition of multilayer films is built based on the existing stress model by considering the influence of deposition conditions. Both thermal stress and intrinsic stress are considered to constitute the final residual stress in the model. The deposition process conditions such as deposition temperature, oxygen pressure, and film growth rate are correlated to the full stress model to analyze the final residual stress distribution, and thus the deformation of the deposited multilayer system under different process conditions. Also, the model is numerically realized with in-house built code. A deposition of Ag-Cu multilayer system is simulated with the as-built extended stress model, and the final residual stresses under different deposition conditions are discussed with part of the results compared with experiment from other literature.

关键词： growth models stresses physical vapor deposition processes polycrystalline deposition metals

Anisometropia magnitude and visual deficits in previously untreated anisometropic amblyopia

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International Journal of Ophthalmology(English edition) 2013年第5期6卷 606-610页

作者： Bin-Bin Chen Feng-Wei song zhao-hui Sun Yi Yang Eye Center the Second Affiliated HospitalSchool of MedicineZhejiang University Department of Ophthalmology the First Affiliated Hospital of Huzhou Teachers College

AIM:To assess the quantitative association between anisometropia magnitude(AM) and the losses of resolution and contrast sensitivity;and to exemplify how the function of fusion and stereopsis vary with AM in previously untreated anisometropic amblyopia. METHODS:A total of 57 patients with previously untreated anisometropic amblyopia without strabismus(range:8-35 years),were measured refractive error,best corrected visual acuity(BCVA),fusion and stereopsis,and 48 patients have completed contrast sensitivity function *** was determined by dioptric vector addition model,and the amblyopia depth was determined by the difference of BCVA in logMAR units between the amblyopic and fellow ***:AM was significantly correlated with both amblyopia depth(Pearson R=0.728,P<0.001) and the inter-ocular difference of the area under the log contrast sensitivity function(AULCSF)(R=0.505,P<0.001).Depth of amblyopia and the inter-ocular difference of AULCSF was also significantly correlated(R=0.761,P<0.001).The more severity of amblyopia,the poorer levels of contrast *** pure anisometropes with AM was less than 3.0D retain fusion and some stereopsis,but when AM were more than 3.0D,especially for the anisometropes whose AM was more than 6.0D,fusion and stereopsis function were seriously ***:In the patients with previously untreated anisometropic amblyopia,higher degree of anisometropia is significantly associated with deeper amblyopia,worse contrast sensitivity,fusion and stereopsis functions.

关键词： anisometropia amblyopia area under the log contrast senility function fusion stereopsis

PICARD ITERATION FOR NONSMOOTH EQUATIONS

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Journal of Computational Mathematics 2001年第6期19卷 583-590页

作者： song-bai Sheng hui-fu Xu College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China Australian Graduate School of Management the University of New South WalesSydneyAustralia

Presents an analysis of the generalized Newton method, approximate Newton methods, and splitting methods for solving nonsmooth equations from Picard iteration viewpoint. Details of the radius of the weak Jacobian of P... 详细信息

关键词： nonsmooth equations picard iteration weak Jacobian convergence