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Journal of Computational Mathematics 1999年第3期17卷 293-306页

作者： xiu-min shao Zhi-ling Lan(Institute of Mathematics, Academy of Sciences, Beijing 100080, China) 中科院数学所北京

In Part I and Part II of this paper initial-boundary value problems of the acoustic wave equation with absorbing boundary conditions are considered. Their finite element-finite difference computational schemes are proposed. The stability of the schemes is discussed and the corresponding stability conditions are given. Part I and Part II concern the first- and the second-order absorbing boundary conditions, respectively. Finally, numerical results are presented in Part II to show the correctness of theoretical analysis. (Author abstract) 7 Refs.

关键词： stability finite element methods wave equation absorbing boundary conditions

A Kind of Discrete Non-Reflecting Boundary Conditions for Varieties of Wave Equations

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Acta Mathematicae Applicatae Sinica 2002年第2期18卷 295-308页

作者： xiu-min shao, Zhi-ling LanInstitute of Mathematics, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, China Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China

In this paper, a new kind of discrete non-reflecting boundary conditions is developed. It can be used for a variety of wave equations such as the acoustic wave equation, the isotropic and anisotropic elastic wave equations and the equations for wave propagation in multi-phase media and so on. In this kind of boundary conditions, the composition of all artificial reflected waves, but not the individual reflected ones, is considered and eliminated. Thus, it has a uniform formula for different wave equations. The velocity CA of the composed reflected wave is determined in the way to make the reflection coefficients minimal, the value of which depends on equations. In this paper, the construction of the boundary conditions is illustrated and CA is found, numerical results are presented to illustrate the effectiveness of the boundary conditions.

关键词： Wave equations non-reflecting boundary conditions

一种醇类水分蒸发抑制剂的开发及在多浪水库的应用

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节水灌溉 2017年第5期 25-28页

作者：吕喜风张娜李秀敏秦少伟李旭塔里木大学现代农业工程重点实验室新疆阿拉尔843300 塔里木大学生命科学学院新疆阿拉尔843300 塔里木大学南疆化工重点实验室新疆阿拉尔843300 塔里木大学信息工程学院新疆阿拉尔843300

为保障新疆农业用水,减少干旱地区水资源的无效蒸发,开发了一种水分蒸发抑制剂。利用十六醇和正丙醇为基材,探讨了组分比例、超声波强度、时间等因素对抑制效果的影响,确立了水分蒸发抑制剂的制备方案。具体方案为十六醇∶正丙醇∶AEO... 详细信息

为保障新疆农业用水,减少干旱地区水资源的无效蒸发,开发了一种水分蒸发抑制剂。利用十六醇和正丙醇为基材,探讨了组分比例、超声波强度、时间等因素对抑制效果的影响,确立了水分蒸发抑制剂的制备方案。具体方案为十六醇∶正丙醇∶AEO总量∶水∶石油醚为0.35∶1∶0.33∶12∶15,超声波处理仪以20%工作强度工作20min。抑制剂用于多浪水库后形成的单分子膜在72 h内使用性能良好。推广使用抑制剂对于减少干旱地区水资源损失具有重大意义,可带来巨大的经济效益和社会效益。

关键词：水分蒸发抑制剂多浪水库水资源保护

Primary parenchymal squamous cell carcinoma of the kidney:A case report

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World Journal of Clinical Cases 2025年第4期13卷 34-40页

作者： Zhi-Hui Zheng Bo shao Chao-min Xu Ke Wang Jia-Zhu Wen Li-Kang Luo Jia-Cheng Guan Department of Ultrasound The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Radiology Shulan(Quzhou)HospitalQuzhou 324000Zhejiang ProvinceChina Department of Radiology The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Pathology The Second people’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina

BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases *** SUMMARY This study reports a 51-year-old man with primary SCC of the renal *** patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross *** antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated *** patient underwent laparoscopic unilateral nephrectomy and lymph node *** pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and *** pathological stage was *** months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena *** patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease *** We report a case of primary SCC of the renal parenchyma,a rare renal *** clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis *** to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered.

关键词： Renal tumor Renal parenchyma Squamous cell carcinoma Renal calculi Computed tomography Case report

ESTIMATION OF DIRECTIONAL SPECTRUM AND REFLECTED COEFFICIENT OF INCIDENT AND REFLECTED WAVE IN PHASE-LOCKED WAVE FIELD

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Journal of Hydrodynamics 2005年第6期17卷 713-723页

作者： shao Li-min YU Zhi-liang YUAN Qun-zhe YU Yu-xiu Department of Ocean and Mapping Science Dalian Naval Academy Dalian 116018 China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116023 China

This paper analyses and compares the property of the Modified Bayesian Directional spectrum analysis Method （MBDM） and the Modified Maximum Lkelihood Method （MMLM） that can he used to estimate directional spectrum and reflected coefficient of phase-locked wave field overlapped by multi directional irregular incident and reflected waves. The numerical test verifies the results under different wave conditions, different measurement systems, and different reflection features. The computation speed and stability of the two methods is also compared. The analysis addresses that the MBDM is better than the MMLM for directional spectrum estimating, while the MMLM is better than the MBDM for reflected coefficient estimation and calculating speed and stability.

关键词： directional spectrum reflected coefficient,Modified Maximum Likelihood Method (MMLM) Modified Bayesian Directional spectrum analysis Method (MBDM)

First-principle study on the surface atomic relaxation properties of sphalerite

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International Journal of minerals,Metallurgy and Materials 2012年第9期19卷 775-781页

作者： Jian Liu Shu-ming Wen Yong-jun Xian shao-jun Bai xiu-min Chen Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 China National Engineering Laboratory of Vacuum Metallurgy Kunming University of Science and Technology Kunming 650093 China

The surface properties of sphalerite （ZnS） were theoretically investigated using first principle calculations based on the density functional theory （DFT）. DFT results indicate that both the （110） and the （220） surfaces of sphalerite undergo surface atom relaxation after geometry optimization, which results in a considerable distortion of the surface region. In the normal direction, i.e., perpendicular to the sur- face, S atoms in the first surface layer move outward from the bulk （dl）, whereas Zn atoms move toward the bulk （d2）, forming an S-enriched surface. The values of these displacements are 0.003 nm for dl and 0.021 nm for d2 on the （110） surface, and 0.002 nm for dl and 0.011 nm for d2 on the （220） surface. Such a relaxation process is visually interpreted through the qualitative analysis of molecular mechanics. X-ray photoelectron spectroscopic （XPS） analysis provides the evidence for the S-enriched surface. A polysulphide （S n^2- ） surface layer with a bind- ing energy of 163.21 eV is formed on the surface of sphalerite after its grinding under ambient atmosphere. This S-enriched surface and the S 2- surface layer have important influence on the flotation properties ofsphalerite. Keywords：

关键词： sphalerite surface relaxation density fimctional theory froth flotation

Investigation of high power laser coatings

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光学精密工程 2005年第4期13卷 471-479页

作者： shao Jian-da FAN Zheng-xiu R＆D Center for Optical Thin Film Coating Technology Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China

High laser-induced damage threshold and large aperture were focuses on the studies of high power laser coatings. This paper reports the research activities at our center. Several measures were developed for evaluating characters of laser damage, including determination of laser induced damage threshold and detection of absorption based on surface thermal lensing technique. Defect was deemed to be the initial source of laser damage, and was the main factor restricting the laser damage resistance of optical coatings. The contribution of several kinds of typical defects to laser damage was analyzed, and some deposition measures were adopted to control and eliminate the origin of defect. Furthermore, some post-treatment methods were also employed to alleviate the influence of the defect and to improve the laser damage resistance. Correction mask was introduced to improve the thickness uniformity, and the thickness uniformity can be amended to less than 1% in the range of Φ650 mm. Preliminary investigation related to surface deformation was also conducted.

关键词：激光涂覆技术 LIDT 吸收能力激光器

Exogenous Nitric Oxide Involved in Subcellular Distribution and Chemical Forms of Cu^(2+) Under Copper Stress in Tomato Seedlings

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Journal of Integrative Agriculture 2013年第10期12卷 1783-1790页

作者： DONG Yu-xiu WANG xiu-feng CUI xiu-min Key Laboratory of Crop Biology Shandong Agricultural University College of Resources and Environment Shandong Agricultural University

Nitric oxide（NO）,a bioactive signaling molecule,serves as an antioxidant and anti-stress agent under abiotic stress.A hydroponics experiment was conducted to investigate the effects of sodium nitroprusside（SNP）,a NO donor,on tomato seedlings exposed to 50 μmol L-1CuCl *** results show that copper is primarily stored in the soluble cell sap fraction in the roots,especially after treatment with Cu＋SNP treatment,which accounted for 66.2% of the total copper *** copper concentration gradually decreased from the roots to the *** the leaves,exogenous NO induces the storage of excess copper in the cell *** stress decreases the proportion of copper integrated with pectates and proteins,but exogenous NO remarkably reverses this *** alleviating effect of NO is blocked by ***,exogenous NO is likely involved in the regulation of the subcellular copper concentrations and its chemical forms under copper *** exogenous NO inhibited the absorption and transport of excess copper to some extent,the copper accumulation in tomato seedlings significantly increased under copper *** use of exogenous NO to enhance copper tolerance in some plants is a promising method for copper remediation.

关键词： tomato seedlings nitric oxide copper stress subcellular distribution chemical form

Existence of Multiple solutions for semilinear elliptic equations in the annulus

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Applied Mathematics(A Journal of Chinese Universities) 2009年第3期24卷 263-268页

作者： MAO An-min MO xiu-ming School of Mathematical Sciences Qufu Normal University Qufu 273165 China Department of Biotechnology Beijing City University Beijing 100094 China

The existence of radial solutions of Δu ＋ λg（｜x｜）f（u） = 0 in annuli with Dirichlet（Dirichlet/Neumann） boundary conditions is *** is proved that the problems have at least two positive radial solutions on an... 详细信息

关键词： fixed point index Dirichlet problems annulus

Derivations and Automorphisms of the Positive Part of the Two-parameter Quantum Group U_(r,s)(B_3)

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Acta Mathematica Sinica,English Series 2017年第2期33卷 235-251页

作者： min LI xiu Ling WANG School of Sciences Tianjin University of Science and Technology School of Mathematical Sciences and LPMC Nankai University

We compute the derivations of the positive part of the two-parameter quantum group Ur,s（B3） and show that the Hochschild cohomology group of degree 1 of this algebra is a three- dimensional vector space over the base field C. We also compute the groups of （Hopf） algebra automorphisms of the augmented two-parameter quantized enveloping algebra Ur,s（B3）.

关键词： Two-parameter quantum group ore extension hochschild cohomology group (Hopf) al- gebra automorphism