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Anisotropic etching mechanisms of 4H-SiC:Experimental and first-principles insights

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Journal of Semiconductors 2024年第1期45卷 42-47页

作者： guang yang Lingbo Xu Can Cui Xiaodong Pi Deren yang Rong Wang Key Laboratory of Optical Field Manipulation of Zhejiang Province Department of PhysicsZhejiang Sci-Tech UniversityHangzhou 310018China State Key Laboratory of Silicon and Advanced Semiconductor Materials&School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Institute of Advanced Semiconductors&Zhejiang Provincial Key Laboratory of Power Semiconductor Materials and Devices HangzhoIun novation CenterZhejiang UniversityHangzhou 311200China

Molten-alkali etching has been widely used to reveal dislocations in 4H silicon carbide(4H-SiC),which has promoted the identification and statistics of dislocation density in 4H-SiC single ***,the etching mechanism of 4H-SiC is limited *** this letter,we reveal the anisotropic etching mechanism of the Si face and C face of 4H-SiC by combining molten-KOH etching,X-ray photoelectron spectroscopy(XPS)and first-principles *** activation energies for the molten-KOH etching of the C face and Si face of 4H-SiC are calculated to be 25.09 and 35.75 kcal/mol,*** molten-KOH etching rate of the C face is higher than the Si *** XPS analysis and first-principles calculations,we find that the molten-KOH etching of 4H-SiC is proceeded by the cycling of the oxidation of 4H-SiC by the dissolved oxygen and the removal of oxides by molten *** faster etching rate of the C face is caused by the fact that the oxides on the C face are unstable,and easier to be removed with molten alkali,rather than the C face being easier to be oxidized.

关键词： principles alkali etching

Amorphous NiMo_(3)S_(13)/nickel foam integrated anode for lithium-ion batteries

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Tungsten 2024年第2期6卷 438-446页

作者： Ming-Xin Shi Min Wu Shan-Shan Xiao Shan-Ping Liu Rui-Qi Yao Ying-Qi Li Yong-Hui Wang yang-guang Li Hua-Qiao Tan Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Faculty of ChemistryNortheast Normal UniversityChangchun 130024China School of Materials Science and Engineering Jilin Jianzhu UniversityChangchun 130118China Institute Charles Gerhardt Montpellier Universite de MontpellierCentre National de la Recherche Scientifi quePlace E.Bataillon34095 Montpellier Cedex 05France

Although crystalline anode materials with long-range ordered lattice structure are in favor of facilitating the electron transfer,their structures are easily disrupted during long-term cycling due to the continuous embedding/de-embedding of lithium *** contrast,the amorphous materials have abundant defects and lithium ion storage sites,refl ecting a superior reaction kinetics and long-term cycling ***,we synthesize an integrated hybrid anode by in-situ loading amorphous NiMo_(3)S_(13)nanosheets on nickel foam *** ting from the introduction of Ni^(2+)that amorphizes the molybdenumsulfur clusters,the assembled lithium ion battery based on the integrated NiMo_(3)S_(13)/nickel foam anode delivers a specifi c capacity up to 1659 mA·h·g^(−1)at a current density of 0.6 A·g^(−1)and exhibits superior rate/cycling performance.

关键词： Molybdenum-sulfur clusters Amorphous Integrated anode Crystalline Lithium-ion batteries

Growth hormone improves insulin resistance in visceral adipose tissue after duodenal-jejunal bypass by regulating adiponectin secretion

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World Journal of Diabetes 2024年第6期15卷 1340-1352页

作者： Zi-Tian Liu guang-Wei yang Xiang Zhao Shuo-Hui Dong yang Jiao Zheng Ge Ao Yu Xi-Qiang Zhang Xin-Zhen Xu Zhi-Qiang Cheng Xiang Zhang Ke-Xin Wang Department of General Surgery Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Department of General Surgery Shandong University of Qilu Hospital(Qingdao)Qingdao 266000Shandong ProvinceChina

BACKGROUND The mechanism of improvement of type 2 diabetes after duodenal-jejunal bypass(DJB)surgery is not *** To study the morphological and functional changes in adipose tissue after DJB and explore the potential mechanisms contributing to postoperative insulin sensitivity improvement of adipose tissue in a diabetic male rat *** DJB and sham surgery was performed in a-high-fat-diet/streptozotocin-induced diabetic rat *** adipose tissue was weighed and observed under *** inguinal fat to represent subcutaneous adipose tissue(SAT)and mesangial fat to represent visceral adipose ***-sequencing was utilized to evaluate gene expression alterations *** hematoxylin and eosin staining,reverse transcription-quantitative polymerase chain reaction,western blot,and enzyme-linked immunosorbent assay were used to study the *** resistance was evaluated by *** After DJB,whole body blood glucose metabolism and insulin sensitivity in adipose tissue *** cell volume in both visceral adipose tissue(VAT)and SAT *** to SAT,VAT showed more significantly functional alterations after DJB and KEGG analysis indicated growth hormone(GH)pathway and downstream adiponectin secretion were involved in metabolic *** circulating GH and adiponectin levels and GH receptor and adiponectin levels in VAT *** experiment showed that GH stimulated adiponectin secretion and improve insulin *** GH improves insulin resistance in VAT in male diabetic rats after receiving DJB,possibly by increasing adiponectin secretion.

关键词： Growth hormone Insulin resistance Bariatric surgery Adipose tissue Adiponectin

Metamorphic P-T conditions and ages of garnet-biotite schists in the Dahongshan Group from the southwestern yangtze Block

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Acta Geochimica 2024年第4期43卷 707-718页

作者： Jun-xiao Ma guang-shu yang Yong-feng Yan Xiao-Fei Xu Yun-hua Ren Hui Zhao Xiao-jun Zheng Yuan Qin Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Geological Team 306 of Yunnan Non-Ferrous Metals Geological Bureau Kunming 650217China Yunnan Provincial Bureau of Non-Ferrous Geology Kunming 650051China

The Dahongshan Group,situated at the southwestern margin of the yangtze Block,represents a geological unit characterized by relatively high-grade metamorphism in the *** paper investigates the garnet-biotite schist from the Laochanghe Formation of the Dahongshan Group,employing an integrated approach that includes petrological analysis,phase equilibrium modeling,and zircon U-Pb *** schist is mainly composed of garnet,biotite,plagioclase,quartz,rutile,and *** equilibrium modeling revealed the peak metamorphic conditions of 8-9 kbar and 635-675°*** further integrating the prograde metamorphic profile of garnet and geothermobarometric results,a clockwise P-T metamorphic evolution path is constructed,which includes an increase in temperature and pressure during the prograde ***-ICP-MS zircon U-Pb dating and zircon Ti thermometry constrains the post-peak metamorphic age of 831.2±7.2 *** with previously reported results,it is revealed that the southwestern margin of the yangtze Block experienced a large-scale regional metamorphism during the Neoproterozoic(890-750 Ma),which is related to the collisional orogenic *** may be associated with the late-stage assembly of the Rodinia supercontinent or with local compression and subduction processes during the breakup of the Rodinia supercontinent.

关键词： Southwestern yangtze Block Dahongshan Group Phase equilibrium modeling Zircon U-Pb dating Neoproterozoic metamorphism

“导演中心”语境下中国当代话剧文体的变革模式及反思

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南京艺术学院学报（音乐与表演版） 2024年第1期 109-114,I0004,I0005页

作者：杨光南京中医药大学医学人文学院江苏南京210023

“导演中心制”的推行影响了话剧文体,“导演时代”的话剧文体与传统文体存在明显的差异。但是,中国和西方在“导演中心”和话剧文体之间形成了不同的变革模式。西方戏剧文体的变革和导演上位都以思想为先导。中国当代话剧文体的变革则... 详细信息

“导演中心制”的推行影响了话剧文体,“导演时代”的话剧文体与传统文体存在明显的差异。但是,中国和西方在“导演中心”和话剧文体之间形成了不同的变革模式。西方戏剧文体的变革和导演上位都以思想为先导。中国当代话剧文体的变革则同舞台形式的革新相关。文体变革模式的选择对中国当代话剧产生了复杂的影响,整体而言,剧本的文学性和演出的文学性都有所下滑。从话剧文体变革模式可以见到中国话剧发展的普遍性问题,思想缺席仍是制约中国话剧发展的最大瓶颈。

关键词：导演中心戏剧文体变革模式

Research on static characteristic of double redundance double nozzle flapper valve based on AMESim

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High Technology Letters 2024年第2期30卷 164-169页

作者：孙亚南 LIANG Qiuhui WANG Wentao yang guang ZHANG Wei Shijiazhuang Haishan Industrial Development Co.Ltd Shijiazhuang 050200P.R.China Fluid Power Transmission and Control Laboratory Yanshan UniversityQinhuangdao 066004P.R.China

The feedback spring rod of the armature assembly is cancelled in the double redundance double nozzle flapper valve(DRDNFV),and the difficulty of valve core displacement control is ***,this paper intends to study the static characteristic of DRDNFV through the AMESet and AMESim *** is explored under the circumstance of the fixed orifices being clogged and experimentally verified on the test *** results show that the pressure gain increases and the flow gain decreases with the increasing clogged degree of the fixed orifices on both *** zero bias increases synchronously with the increasing clogged degree of the unilateral fixed *** experimental results are basically consistent with the theoretical curves and the theoretical correctness of the simulation model is effectively *** results can provide the theoretical reference for design,debugging,maintenance and fault diagnosis of DRDNFV.

关键词： double redundance double nozzle flapper valve(DRDNFV) AMESet torquemotor armature assembly fault diagnosis

多道负刚度阻尼伸臂结构减震性能的随机响应分析

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建筑结构学报 2024年第5期45卷 55-68页

作者：孙飞飞杨光刘越杨嘉琦同济大学土木工程防灾国家重点实验室上海200092 同济大学建筑工程系上海200092

针对传统黏滞阻尼伸臂(conventional damped outrigger, CDO)结构中由于外柱刚度有限造成最大附加阻尼比受限的不足,引入负刚度机制,将负刚度装置与阻尼器并联,形成负刚度阻尼伸臂(negative stiffness damped outrigger, NSDO)结构,在... 详细信息

针对传统黏滞阻尼伸臂(conventional damped outrigger, CDO)结构中由于外柱刚度有限造成最大附加阻尼比受限的不足,引入负刚度机制,将负刚度装置与阻尼器并联,形成负刚度阻尼伸臂(negative stiffness damped outrigger, NSDO)结构,在降低阻尼需求、控制结构的风振及地震作用响应方面具有显著的优势。基于连续化的Timoshenko梁建立多道负刚度阻尼伸臂结构的简化分析模型,并通过虚拟小质量法建立核心筒-伸臂结构的状态空间方程,最终通过求解Lyapunov方程得到结构的随机地震响应。并以两道伸臂为例,对两道NSDO(简称“2NSDO”)结构、两种布置方案的混合伸臂结构进行了随机地震响应参数化分析。结果表明:与传统阻尼伸臂结构相比,合理设置的NSDO结构的减震效果明显提高,层间位移角与无控结构(仅核心筒)层间位移角之比(即层间位移角减震效果)从0.68降至0.25以下,有害层间位移角的减震效果从0.71降至0.4以下,加速度、基底剪力和倾覆弯矩的减震效果均从0.7左右降至0.5以下;对比不同的NSDO布置形式,对于有害层间位移角、加速度、基底剪力和倾覆弯矩指标,2NSDO结构和传统伸臂(conventional outrigger, CO)在下部、NSDO在上部(1CO+1NSDO)的混合伸臂结构具有基本相同的显著减震效果,均能降至0.55以下,NSDO在下部、CO在上部(1NSDO+1CO)混合伸臂结构的可降至0.82以下;对于层间位移角,2NSDO结构的减震效果最好,可降至0.25左右,1CO+1NSDO和1NSDO+1CO结构的分别降至0.3和0.4以下。综合考虑减震效果及对结构静力刚度的影响,工程中更推荐采用1CO+1NSDO的伸臂布置形式。

关键词：伸臂结构负刚度阻尼伸臂多伸臂随机地震响应减震效果

冻融损伤过程中纤维加筋土的抗压性能与裂隙演化

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土木工程学报 2024年第4期57卷 81-91页

作者：魏丽杨光尚军柴寿喜天津城建大学天津市软土特性与工程环境重点实验室天津300384 天津城建大学地质与测绘学院天津300384

冻融损伤土的微观结构,土中产生微裂隙,宏观上表现为土的力学性能下降。文章完成了石灰固化土和纤维与石灰加筋固化土的冻融试验、无侧限抗压强度试验、CT扫描试验,分析冻融损伤过程中石灰固化土和纤维与石灰加筋固化土的抗压性能与裂... 详细信息

冻融损伤土的微观结构,土中产生微裂隙,宏观上表现为土的力学性能下降。文章完成了石灰固化土和纤维与石灰加筋固化土的冻融试验、无侧限抗压强度试验、CT扫描试验,分析冻融损伤过程中石灰固化土和纤维与石灰加筋固化土的抗压性能与裂隙演化特征,评价纤维对提高土的抗冻融性能的积极作用。结果表明:石灰固化土、纤维与石灰加筋固化土的抗压强度与破坏应变均随冻融次数的增加呈阶段性下降,即降幅较大阶段、降幅较小阶段和强度基本稳定阶段,纤维加筋显著提高了土的抗变形性能;土的压实度越大,纤维加筋提高土的力学性能就越明显;冻融过程中,裂隙主要分布在试样的表面、上部和下部,面裂隙率随扫描层数的增加呈先减小后增大的变化规律;纤维与石灰加筋固化土的体裂隙率、裂隙长度均值、裂隙宽度均值均小于石灰固化土,纤维加筋延缓了裂隙的形成、发展与连通。纤维与石灰加筋固化土的抗压性能与抗冻融性能显著优于石灰固化土,纤维加筋减弱了冻融土的微观结构损伤程度。

关键词：固化土纤维加筋土冻融损伤抗压性能裂隙演化

Effect of SARS-CoV-2 infection in early pregnancy on placental development

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Science China(Life Sciences) 2024年第3期67卷 622-625页

作者： Shanru Yi Liping Wang Mengting Wang Wei Hong Ben Xu Xiaoying He Mengtian yang Zhiping Wu Beiying Wang guang yang Shijun Shen Xinyu Cui Ruixue Wang Kai Wang Hong Wang Xiaocui Li Shaorong Gao Cizhong Jiang Jiayu Chen Clinical and Translation Research Center of Shanghai First Maternity and Infant Hospital Shanghai Key Laboratory of Signaling and Disease ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of the Ministry of Education Orthopaedic Department of Tongji HospitalTongji UniversityShanghai 200065China Frontier Science Center for Stem cell Research Tongji UniversityShanghai 200092China Shanghai Key Laboratory of Maternal Fetal Medicine Shanghai First Maternity and Infant HospitalSchool of MedicineTongji UniversityShanghai 201204China

Dear Editor,Since the COVID-19 pandemic, the potential risks associated with maternal SARS-CoV-2 infection and its effect on fetal development have been a subject of considerable public concern. Previous studies have ... 详细信息

关键词： pregnancy fetal Effect