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Robot-assisted retroperitoneal laparoscopic excision of perirenal vascular tumor: A case report

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World Journal of Clinical Cases 2020年第10期8卷 2050-2055页

作者： Cheng Zhang Bin fu Song Xu Xiao-Chen Zhou Xiao-Feng Cheng wen-qing fu Gong-Xian Wang Department of Urology The First Affiliated Hospital of Nanchang UniversityNanchang 330000JiangXi ProvinceChina

BACKGROUND A vascular tumor is a benign tumor with unique clinical and pathological *** vascular tumor is extremely rare and has not yet been ***,it manifests as soreness and *** ultrasound and renal angiography illustrated the perirenal mass,which was closely connected with the kidney and the surrounding tissues and *** showed extensive embedded perirenal fat,and thin-walled vascular tissue displayed a pink stain due to red blood *** SUMMARY Herein,a case of robot-assisted retroperitoneal laparoscopic excision of a perirenal vascular tumor is *** of the clinical,biological,and histological features of the perirenal vascular tumor can provide an in-depth understanding of the disease,which provides a theoretical and practical basis for better diagnosis and *** This study contributes to a practical basis for the diagnosis and treatment of perirenal hemangiom.

关键词： Kidney Vascular tumor Treatment Robot-assisted surgery

Ti-Ni合金的织构与弹性模量及伪弹性应变的定量关系

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上海交通大学学报 2002年第5期36卷 608-611页

作者：杨树强袁文庆沈甫法上海交通大学材料科学与工程学院上海200030

应用取向分布函数 ( Orientation Distribution function,ODF)方法分析了形状记忆合金Ti- 5 0 .4% Ni(原子分数 )热轧后的织构 ,结果表明其织构类型为 α纤维 .根据其织构系数计算了不同轧向的弹性模量 ,并由 ODF回算的反极图计算了不... 详细信息

应用取向分布函数 ( Orientation Distribution function,ODF)方法分析了形状记忆合金Ti- 5 0 .4% Ni(原子分数 )热轧后的织构 ,结果表明其织构类型为 α纤维 .根据其织构系数计算了不同轧向的弹性模量 ,并由 ODF回算的反极图计算了不同轧向的伪弹性应变 .经实验证实 ,得到了Ti- 5 0 .4%

关键词： Ti-Ni形状记忆合金取向分布函数弹性模量伪弹性应变

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无机填料对硅橡胶基耐热复合涂层的影响

北京工业大学学报 2025年第1期51卷 13-21页

作者：杨晓军文卿符寒光贺定勇北京工业大学材料科学与工程学院焊接与表面工程技术研究所北京100124

以硅橡胶为基体,添加无机填料制备的耐热涂层在耐热防腐方面有重要应用前景。采用自制改性硅橡胶作基体,添加不同配比的高岭土、二氧化硅和氧化铝,制备了复合涂层。采用扫描电子显微镜(scanning electron microscopy,SEM)观察了硅橡胶... 详细信息

以硅橡胶为基体,添加无机填料制备的耐热涂层在耐热防腐方面有重要应用前景。采用自制改性硅橡胶作基体,添加不同配比的高岭土、二氧化硅和氧化铝,制备了复合涂层。采用扫描电子显微镜(scanning electron microscopy,SEM)观察了硅橡胶基体中无机填料的分散状况,采用热重分析仪(thermogravimetric analyzer,TGA)对复合涂层的热解温度和失重率进行了分析。结果表明:在复合体系中,无机填料与基体的相容性较好,分散均匀;与基体材料相比,无机填料的添加可有效提高复合材料的耐热性。填料质量分数为20%的复合涂层,其在800℃时质量残留率比自制改性硅橡胶的基体提高了10%以上。

关键词：硅橡胶高岭土耐热性微观形貌涂层复合材料

A versatile synthetic strategy towards rare earth based metal-organic frameworks

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Science China Chemistry 2025年

作者： Quan Shi Yun-Hao Xu Ming-Hui Chen Peng Zhao wen-Bo Deng Ji Xiong Kai Guo Ya-qing Feng Bao Zhang School of Chemical Engineering and Technology Tianjin University Tianjin Collaborative Innovation Center of Chemical Science and Engineering Guangdong Laboratory Chemistry & Fine Chemical Industry Jieyang Center

Rare earth metal-organic frameworks (RE-MOFs) have drawn wide attention owing to diverse network structures and various application ***,due to the unpredictable formation of the nodes,it is still challenging to design novel RE-MOFs.A novel versatile strategy was developed employing a RE-acetate complex (RE2(CH3COO)6·4H2O) as a precursor to construct RE-MOFs.2D RE-MOFs (RE-DBP) and 3D RE-MOFs (RE-TCPP) could be obtained by using dicarboxylic porphyrin ligands H2DBP and tetracarboxylic porphyrin ligands H2TCPP,*** RE-MOFs were further synthesized to verify the universality of the *** crystalline RE-MOFs could also be prepared at room temperature via the developed strategy,which could significantly promote large-scale preparation and practical application of *** proof of the concept,the performance of porphyrin-based RE-MOFs was investigated in the photocatalytic cycloaddition of CO2with *** the RE-DBP(Co) MOFs,Tb-DBP(Co) exhibited the best photocatalytic performance,which was also greater than that of the corresponding 3D MOF Tb-TCPP(Co) due to the optimal 2D structure and thus the accelerated photogenerated charge separation and transfer *** work not only provides a novel versatile strategy to design and develop RE-MOFs,but also proposes a promising approach for the potential bulk production of RE-MOFs at room temperature.

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Precise Deviations for Discrete Ensembles

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Acta Mathematica Sinica,English Series 2023年第8期39卷 1580-1596页

作者： wen Xuan CHEN fu qing GAO School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

We consider precise deviations for discrete ***β=2 case,we first establish an asymptotic formula of the Christoffel–Darboux kernel of the discrete orthogonal polynomials on an infinite regular lattice with weight e^(−NV(x)).Then we use the asymptotic formula to get the precise deviations of the extreme value for corresponding ensemble.

关键词： Discrete ensemble precise deviation random growth model Riemann-Hilbert problem

Phase transformation behaviors and mechanical properties of Ti_(50)Ni_(49)Fe_1 alloy with severe plastic deformation

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Rare Metals 2013年第5期32卷 448-452页

作者： wen Ma Bin Chen fu-Shun Liu qing Xu Division of Science and Technology Information General Research Institute for Nonferrous Metals School of Material Science and Engineering Beijing University of Aeronautics and Astronautics Metrology and Phsico-Chemical Institute Capital Aerospace Machinery Company

In this work, transformation behaviors and mechanical properties of cold-rolled shape memory alloy TisoNia9Fel by severe plastic deformation （SPD） were intensively investigated. The phase transformation behaviors, phase analysis, and microstructures were characterized by differential scanning calorimetry （DSC）, X-ray diffraction （XRD）, and transmission electron microscopy （TEM）, respectively. Tensile testing was performed to analyze the effect of SPD on the mechanical properties and shape memory of TisoNi49Fel alloy. When the thickness reduction is beyond 30 %, the martensitic transformation is suppressed. After cold-rolling, the alloy is mainly com- posed of B2 parent phases with some stress-induced martensitic B 19t phases, and high density of dislocations are generated and the grains are obviously refined. The yield stress ab significantly raises from 618 MPa of 0 % cold rolling to 1,338 MPa of 50 % SPD. Shape-memory effect increases from 6.5 % without cold rolling to 8.5 % after 30 % SPD, ascribed to the induced defects in cold rolling. Those results indicate that TisoNi49Fel alloy has improved mechanical properties and potential commercial applications after SPD.

关键词： TiNiFe alloy Cold-rolling Severe plasticdeformation (SPD) Shape memory effect

Significantly Enhanced Melt Memory Effect of Metallocene-made Isotactic Polypropylene Containing Talc

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Chinese Journal of Polymer Science 2024年第2期42卷 213-222,I0008页

作者： Hong-wen Sun fu-Shan Wang Yan Gao fu-qing Wei Jia-Chun Feng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China Lanzhou Petrochemical Corporation of PetroChina Lanzhou730060China Lanzhou Petrochemical Research Center Petrochemical Research Institute of PetroChinaLanzhou730060China

The melt memory effect is a widely observed phenomenon in semi-crystalline polymers. In practical applications, various additives are usually introduced into polymers, which may affect their melt memory behavior. In this work, the effect of talc on the melt memory effect of metallocene-made isotactic polypropylene(M-PP) was investigated in detail by using the differential scanning calorimetry. The results indicated that the introduction of talc significantly strengthened the melt memory effect of M-PP. Specifically, the upper limit temperature of Domain II increased from 161 ℃ to 174 ℃, resulting in a substantial widening of the temperature range of Domain IIa from 1 ℃ to 14 ℃. Analysis of the crystal orientation of the M-PP containing talc cooled from various Ts suggested that the remarkably enhanced melt memory effect could be ascribed to the stabilization of oriented nuclei facilitated by talc. This stabilizing effect was likely attributable to the prefreezing effect or the sorption interaction between talc and the M-PP chains.

关键词： Metallocene-made isotactic polypropylene Talc Melt memory effect Crystal orientation

美国小学科学教育标准修订的内容、特点及启示

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教学与管理 2025年第2期 73-76页

作者：张绍清付超然赣南师范大学教育科学学院赣南师范大学物理与电子信息学院

美国的《新一代科学教育标准》代表了科学教育的创新进步，整合了前沿科研，并修正了旧标准的问题。通过分析《新一代科学教育标准》在教学素养、课程内容、教学方法和评估方面的创新，以及凸显科学学科的基础作用、学科工具的运用、学... 详细信息

美国的《新一代科学教育标准》代表了科学教育的创新进步，整合了前沿科研，并修正了旧标准的问题。通过分析《新一代科学教育标准》在教学素养、课程内容、教学方法和评估方面的创新，以及凸显科学学科的基础作用、学科工具的运用、学科理念的革新和教育目标的重新定位等新特征，从科学教育理念、内容与方法方面为我国科学教育的发展提出建议。

关键词：美国小学科学教育科学课程教育标准

Assessment of subgrid-scale models in wall-modeled large-eddy simulations of turbulent channel flows

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Journal of Hydrodynamics 2023年第3期35卷 407-416页

作者： Wei-wen Zhao fu-chang Zhou Guo-qing Fan De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Wuhan Second Ship Design and Research Institute Wuhan 430205China

Considering the demanding of grid requirements for high-Reynolds-number wall-bounded flow,the wall-modeled large-eddy simulation(WMLES)is an attractive method to deal with near wall ***,the effect of subgrid-scale(SGS)models for wall-bounded turbulent flow in combination with wall stress models is still *** this paper,turbulent channel flow at Reτ=1000 are numerically simulated by WMLES in conjunction with four different SGS models,i.e.,the wall-adapting local eddy-viscosity model,the dynamic Smagorinsky model,the dynamic SGS kinetic energy model and the dynamic Lagrangian *** mean velocity profiles are compared with the law of the wall,and the velocity fluctuations are compared with direct numerical simulation *** energy spectrum of velocity and wall pressure fluctuations are presented and the role of SGS models on predicting turbulent channel flow with WMLES is discussed.

关键词： Wall-modeled large-eddy simulation(WMLES) subgrid-scale(SGS)model turbulent channel flow energy spectra