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An Elastic Shell Model for the Human Tricuspid Valve

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Acta Mathematicae Applicatae Sinica 2019年第1期35卷 111-128页

作者： Xiao-qin SHEN Qian YANG lin-jin li li CAI Xiao-shan CAO Xi’an University of Technology NPU-UoG International Cooperative Lab for Computation & Application in Cardiology Northwestern Polytechnical University Department of Mathematical University of Delaware

The human tricuspid valve, one of the key cardiac structures, plays an important role in the circulatory system. However, there are few mathematical models to accurately simulate *** this paper, firstly, we consider the tricuspid valve as an elastic shell with a specific shape and establish its novel geometric model. Concretely, the anterior, the posterior and the septal leaflets of the valve are supposed to be portions of the union of two interfacing semi-elliptic cylindrical shells when they are fully ***, we use Koiter's linear shell model to describe the tricuspid valve leaflets in the static case, and provide a numerical scheme for this elastostatics model. Specifically, we discretize the space variable, i.e., the two tangent components of the displacement are discretized by using conforming finite elements(linear triangles) and the normal component of the displacement is discretized by using conforming Hsieh-Clough-Tocher triangles(HCT triangles).Finally, we make numerical experiments for the tricuspid valve and analyze the outcome. The numerical results show that the proposed mathematical model describes well the human tricuspid valve subjected to applied forces.

关键词： tricuspid valve geometric model parametric equation Koiter model conforming finite element

The Herbicidal Activity of Mutant Isolates from Botrytis cinerea

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Agricultural Sciences in China 2006年第8期5卷 622-628页

作者： ZHANG jin-lin ZHANG li-hui liU Ying-chao MA Juan li Chuan DONG jin-gao Mycotoxin Laboratory Hebei Agricultural University Baoding 071001 P.R.China

Fifteen mutant isolates were obtained by ultraviolet mutation from parent isolate Botrytis cinerea BC-4. Among them three mutant isolates, BC4-1, BC4-2, and BC4-15, showed strong herbicidal activity. BC4-1 showed maximum herbicidal activity for inhibition of germination and growth of Digitaria sanguinalis L. and Arnaranthus retroflexus L. The results also showed that herbicidal activity was influenced by differing pH of PD media, with pH value of 4.0 being the optimum. The crude toxin was extracted using chloroform, petroleum ether, and ethyl acetate, respectively, and the ethyl acetate extracts showed the strongest inhibitory activity on the germination and growth of D. sanguinalis L. and A. retroflexus L. Using HPLC, one fraction with an absorption peak at 271 nm was separated from the crude toxin. This fraction could strongly inhibit the growth of D. sanguinalis L. at a concentration of 100 mg L^-1 and could completely inhibit the seed germination of D. sanguinalis L. and A. retroflexus L. at a concentration of 50 mg L^-1 .

关键词： Botrytis cinerea toxin ultraviolet mutation herbicide activity separation and purification

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai li Zhen Ma jin-Hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

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TDDB击穿特性评估薄介质层质量

电子学报 2000年第5期28卷 80-83,74页

作者：胡恒升张敏林立谨中国科学院上海冶金研究所微电子学分部上海200233

与时间相关电介质击穿 (TDDB)测量是评估厚度小于 2 0nm薄栅介质层质量的重要方法 .氧化层击穿前 ,隧穿电子和空穴在氧化层中或界面附近产生陷阱、界面态 ,当陷阱密度超过临界平均值 ρbd时 ,发生击穿 .击穿电量Qbd值表征了介质层的质... 详细信息

与时间相关电介质击穿 (TDDB)测量是评估厚度小于 2 0nm薄栅介质层质量的重要方法 .氧化层击穿前 ,隧穿电子和空穴在氧化层中或界面附近产生陷阱、界面态 ,当陷阱密度超过临界平均值 ρbd时 ,发生击穿 .击穿电量Qbd值表征了介质层的质量 .Qbd值及其失效统计分布与测试电流密度、电场强度、温度及氧化层面积等有定量关系 .TDDB的早期失效分布可以反映工艺引入的缺陷 .TDDB可以直接评估氧化、氮化、清洗、刻蚀等工艺对厚度小于 10nm的栅介质质量的影响 .它是硅片级评估可靠性和预测EEPROM擦写次数的重要方法 .

关键词：薄介质层 VLSI 集成电路 TDDB 击穿特性

Nanostructured ZnO/BiVO_(4)I-scheme heterojunctions for piezocatalytic degradation of organic dyes via harvesting ultrasonic vibration energy

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 488-497页

作者： Yiling li Xiaoyao Yu Yingjie Zhou Yao lin Ying Wu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua 321004China

BiVO_(4)porous spheres modified by ZnO were designed and synthesized using a facile two-step *** resulting ZnO/BiVO_(4)composite catalysts have shown remarkable efficiency as piezoelectric catalysts for degrading Rhodamine B(RhB)unde mechanical vibrations,they exhibit superior activity compared to pure *** 40wt%ZnO/BiVO_(4)heterojunction composite displayed the highest activity,along with good stability and *** enhanced piezoelectric catalytic activity can be attributed to the form ation of an I-scheme heterojunction structure,which can effectively inhibit the electron-hole ***,hole(h+)and superoxide radical(·O_(2)^(-))are proved to be the primary active ***,ZnO/BiVO_(4)stands as an efficient and stable piezoelectric catalyst with broad potential application in the field of environmental water pollution treatment.

关键词： piezoelectric catalytic heterojunction dye degradation ultrasonic vibration

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薄SiO_2层击穿特性与临界陷阱密度

电子学报 2000年第8期28卷 59-62页

作者：林立谨张敏中科院上海冶金研究所微电子学分部--上海微电子研究开发基地上海200233

薄栅氧化层的退化、击穿与氧化层中和界面陷阱的产生相关 .本文研究了在恒电流TDDB(Time Depen dentDielectricBreakdown)应力条件下 8 9nm薄氧化层的电学特性退化、击穿情况 .研究表明 ,电子在穿越SiO2 晶格时与晶格相互作用产生陷阱 ... 详细信息

薄栅氧化层的退化、击穿与氧化层中和界面陷阱的产生相关 .本文研究了在恒电流TDDB(Time Depen dentDielectricBreakdown)应力条件下 8 9nm薄氧化层的电学特性退化、击穿情况 .研究表明 ,电子在穿越SiO2 晶格时与晶格相互作用产生陷阱 ,当陷阱密度达到某一临界密度Nbd时 ,氧化层就击穿 .Nbd可以用来表征氧化层的质量 ,与测试电流密度无关 .击穿电量Qbd随测试电流密度增大而减小可用陷阱产生速率的增长解释 .临界陷阱密度Nbd随测试MOS电容面积增大而减小 ,这与统计理论相符 .统计分析表明 ,对于所研究的薄氧化层 ,可看作由面积为 2 5 6× 10 -14cm2 的“元胞”构成 ,当个别“元胞”中陷阱数目达到 13个时 ,电子可通过陷阱直接隧穿 ,“元胞”内电流突然增大 ,产生大量焦耳热 ,形成欧姆通道 ,氧化层击穿 .

关键词：薄栅氧化层击穿特性临界陷阱密度二氧化硅

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： jin-Peng Wang Guo-Cui Mao Hui-lin Jiang Bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： lin Peng Yu Bai Hang li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

lithium-sulfur （li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （liPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes li2S dissolution and nucleation ***,the li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： lithium sulfur batteries

灾害事故中应急志愿者与救援任务双边匹配影响因素分析

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安全与环境学报 2023年第1期23卷 161-169页

作者：林丽金陈圣群申亮福建商学院信息工程学院福州350001 大数据商务智能福建省高校工程研究中心福州350001

分析应急志愿者与救援任务双边匹配影响因素,有助于在灾害事故中高效派遣志愿者和分配救援任务。基于文献数据、权威网站、街头采访、专家咨询等数据构建应急志愿者与救援任务双边匹配的初级指标;采用皮卡尔系数方法分析影响因素与被解... 详细信息

分析应急志愿者与救援任务双边匹配影响因素,有助于在灾害事故中高效派遣志愿者和分配救援任务。基于文献数据、权威网站、街头采访、专家咨询等数据构建应急志愿者与救援任务双边匹配的初级指标;采用皮卡尔系数方法分析影响因素与被解释变量相关性,以及热力图方法观察指标特征。随后采用随机森林与弹性网络组合方法分析志愿者与救援任务双边匹配影响因素。结果表明:随机森林方法在分析救援任务选择志愿者影响因素时,模型稳定,测试集的损失函数均方误差较小,因此采用随机森林方法确定救援任务选择志愿者的影响因素。弹性网络方法在分析志愿者选择救援任务影响因素时,模型更稳定、精度更高,其测试集的损失函数均方误差比随机森林模型提升近3倍。因此采用弹性网络方法确定志愿者选择救援任务的影响因素。

关键词：公共安全弹性网络随机森林双边匹配影响因素

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