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UHMWPE背板厚度对铝复合板抗侵彻增强效应分析

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爆炸与冲击 2024年第2期44卷 70-85页

作者：杨可谞何成龙霍子怡毛翔中北大学机电工程学院山西太原030051

为研究超高分子聚乙烯(ultra-high molecular weight polyethylene,UHMWPE)背板厚度对铝复合板抗钨球侵彻效果的影响,利用数字图像相关方法(digital image correlation method,DIC)与X射线电子计算机断层扫描(computed tomography,CT)得到UHMWPE受到冲击后的动态响应及局部破坏。建立钨球以不同速度侵彻Al/UHMWPE复合板的有限元模型,研究不同冲击速度下UHMWPE背板厚度对复合靶板吸能性能的影响,所用背板厚度为1.6~20 mm。结果表明:铝板在冲击作用下发生绝热剪切破坏,正交铺设纤维层产生纤维凸起和分叉应变带。随着背板厚度增大,纤维层由剪切破坏向拉伸破坏过度,纤维层应变带由十字形转变为X形。UHMWPE板厚度的增大有效地阻碍了铝块塞体运动,从而增加了破片侵彻铝板的时间与动能消耗。UHMWPE背板厚度对吸能性能影响呈先快速上升至阈值,后缓慢下降的趋势,说明PE板到达一定厚度后,通过增加厚度的方法来提升其吸能性能的作用有限。

关键词： UHMWPE 铝复合板抗钨球冲击模拟抗侵彻行为

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A Within-Host Model of Dengue Infection with a Non-Constant Monocyte Production Rate

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Applied Mathematics 2016年第18期7卷 2382-2393页

作者： jeremy j. Thibodeaux Michael Hennessey Department of Mathematical Sciences Loyola University New Orleans New Orleans LA USA Department of Mathematical Sciences Rensselaer Polytechnic Institute Troy NY USA

In this paper we modify previous models to develop a new model of within-host dengue infection without the assumption that monocyte production is constant. We show that this new model exhibits behavior not seen in previous models. We then proceed by obtaining an expression for the net reproductive rate of the virus and thus establish a stability result. We also perform a sensitivity analysis to test various treatment strategies and find that two strategies might be fruitful. One is the reduction of the infection rate of monocytes by viruses and the other, more effective, theoretical approach is to reduce the number of new viruses per infected monocyte.

关键词： Dengue Within-Host Model Net Reproductive Rate Treatment Scenarios

Well-Posedness and a Finite Difference Approximation for a Mathematical Model of HPV-Induced Cervical Cancer

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Applied Mathematics 2023年第3期14卷 151-172页

作者： Baoling Ma jeremy j. Thibodeaux Department of Mathematics Millersville University Millersville PA USA Department of Mathematical Sciences University of the Virgin Islands St. Croix USVI USA

We present a first-order finite difference scheme for approximating solutions of a mathematical model of cervical cancer induced by the human papillomavirus (HPV), which consists of four nonlinear partial differential equations and a nonlinear first-order ordinary differential equation. The scheme is analyzed and used to provide an existence-uniqueness result. Numerical simulations are performed in order to demonstrate the first-order rate of convergence. A sensitivity analysis was done in order to compare the effects of two drug types, those that increase the death rate of HPV-infected cells, and those that increase the death rate of the precancerous cell population. The model predicts that treatments that affect the precancerous cell population by directly increasing the corresponding death rate are far more effective than those that increase the death rate of HPV-infected cells.

关键词： Age Structured Cervical Cancer Finite Difference Human Papillomavirus Mathematical Model

基于代谢组学分析不同品系化州柚花间差异代谢物

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果树学报 2024年第10期41卷 1990-2001页

作者：陈婉冰毛根林钟玉娟曾继吾广东省农业科学院果树研究所·农业农村部南亚热带果树生物学与遗传资源利用重点实验室·广东省果树科学与技术研究重点实验室广州510640 广东省农业科学院蔬菜研究所·广东省蔬菜新技术研究重点实验室广州510640

【目的】研究化州柚(Citrus grandis‘Tomentosa’)正毛、副毛和光青品系的花之间成分差异,为化州柚花在医药和保健领域的开发应用奠定基础。【方法】选取同一生长期的化州柚正毛、副毛和光青3个品系的花,利用超高效液相色谱-三重四极... 详细信息

【目的】研究化州柚(Citrus grandis‘Tomentosa’)正毛、副毛和光青品系的花之间成分差异,为化州柚花在医药和保健领域的开发应用奠定基础。【方法】选取同一生长期的化州柚正毛、副毛和光青3个品系的花,利用超高效液相色谱-三重四极杆质谱(UPLC-MS/MS)进行次级代谢产物的广泛靶向代谢组学分析,利用气相色谱-四级杆飞行时间质谱(GC-TOF/MS)进行初级代谢产物的非靶向代谢组学分析。通过主成分分析(PCA)揭示3个品系花间的整体差异,利用正交偏最小二乘法判别分析(OPLS-DA)将3个品系两两对比,筛选出品系间的差异代谢物。【结果】UPLCMS/MS检测发现978种代谢物,其中63种代谢物在不同品系花中表现出显著差异。地奥司明、山柰酚-3-O-芸香糖苷、芦丁、牡荆素-2''-O-葡萄糖苷、木犀草素-7-O-芸香糖苷、维采宁-2、芸香柚皮苷、香草酸、佛手苷内酯和橙皮内酯10种化州柚中有效成分在副毛和正毛花中的含量高于光青。GC-TOF/MS检测发现236种代谢物,筛选出11种差异代谢物,包括D-(-)果糖、D-纤维二糖、景天酮庚糖、α-槐糖、丙酮酸、柠檬酸、莽草酸、反式-4-羟基肉桂酸、咖啡酸、阿魏酸和柚皮素-7-O-葡萄糖苷。【结论】化州柚正毛、副毛和光青3个品系的花在成分上存在显著差异,尤其是副毛和正毛花的有效成分含量高于光青。

关键词：化州柚化橘红代谢组学

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斜撑桩承载力自检检测方法的应用对比分析

宁波大学学报（理工版） 2024年第5期37卷 21-26页

作者：毛红辉金超奇宁波宁大地基处理技术有限公司浙江宁波315211

为提高斜撑桩极限承载力自检效率,提出了新的自检检测方法—–超快速维持荷载法(简称“超快速法”),结合工程实例对相同设计参数斜撑桩的“超快速法”与“快速法”Q—S曲线进行了对比分析;除此之外,对同一根斜撑桩采用“超快速法”与“... 详细信息

为提高斜撑桩极限承载力自检效率,提出了新的自检检测方法—–超快速维持荷载法(简称“超快速法”),结合工程实例对相同设计参数斜撑桩的“超快速法”与“快速法”Q—S曲线进行了对比分析;除此之外,对同一根斜撑桩采用“超快速法”与“快速法”先后检测的Q—S曲线进行了对比分析.分析结果表明:“超快速法”与“快速法”检测结果基本相近,两者偏差为0~8.7%;“超快速法”经验证可行且检测结果可应用于工程实际.

关键词：斜撑桩超快速维持荷载法静载试验极限承载力

DG algebra structures on AS-regular algebras of dimension 2

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Science China Mathematics 2011年第10期54卷 2235-2248页

作者： mao XueFeng Department of Mathematics Shanghai University Shanghai 200444 China

Let A be a connected cochain DG algebra, whose underlying graded algebra is an Artin-Schelter regular algebra of global dimension 2 generated in degree 1. We give a description of all possible differential of A and compute H（A）. Such kind of DG algebras are proved to be strongly Gorenstein. Some of them serve as examples to indicate that a connected DG algebra with Koszul underlying graded algebra may not be a Koszul DG algebra defined in He and We （j.Algebra, 2008, 320： 2934-2962）. Unlike positively graded chain DG algebras, we give counterexamples to show that a bounded below DC A-module with a free underlying graded A^#-module may not be semi-proj.ctive.

关键词： AS-regular algebra differential graded algebra Koszul algebra semi-proj.ctive module

Study on Nucleophilic Additions to endo-tricyclo[5.2.1.0^(2,6)]deca-2(6),8-dien-3-one and an Unusual Payne Rearrangement of α,β-Epoxy Tricyclodecenone

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Chinese Chemical Letters 2001年第7期12卷 585-588页

作者： Xue Shi mao A.A.VOLKERS A.j.H.KLUNDER Binne ZWANENBURG Department of Organic Chemistry NSR Center for Molecular StructureDesign and SynthesisUniversity of NijmegenToernooiveld 16525 ED NijmegenThe Netherlands

Synthesis of highly strained tetracyclic ketones was achieved by cyclopropanation or epoxidation of tricyclodecenone 1. An unusual formation of α-methoxy β-hydroxy ketone from an α,β-unsaturated enone system via ... 详细信息

关键词： Nucleophilic addition Payne rearrangement α β-epoxycyclopentanone

Effect of oxygen and nitrogen functionalization on the physical and electronic structure of graphene

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Nano Research 2015年第8期8卷 2620-2635页

作者： Alexander j. Marsden Peter Brommer j.mes j. Mudd M. Adam Dyson Robert Cook Maria Asensio j.se Avila Ana Levy jeremy Sloan David Quigley Gavin R. Bell Neil R. Wilson Department of Physics University of Warwick Coventry UK Centre for Scientific Computing University of Warwick Coventry UK Synchrotron SOLEIL L'Orme des Merisiers Saint Aubin-BP 48 91192 Gifsur Yvette Cedex France

Covalent functionalization of graphene offers opportunities for tailoring its properties and is an unavoidable consequence of some graphene synthesis techniques. However, the changes induced by the functionalization are not well understood. By using atomic sources to control the extent of the oxygen and nitrogen functionalization, we studied the evolution in the structure and properties at the atomic scale. Atomic oxygen reversibly introduces epoxide groups whilst, under similar conditions, atomic nitrogen irreversibly creates diverse functionalities including substitutional, pyridinic, and pyrrolic nitrogen. Atomic oxygen leaves the Fermi energy at the Dirac point （i.e., undoped）, whilst atomic nitrogen results in a net n-doping; however, the experimental results are consistent with the dominant electronic effect for both being a transition from delocalized to localized states, and hence the loss of the signature electronic structure of graphene.

关键词： graphene functionalization chemical vapor deposition density functional theory

Facial Selectivity in the Nucleophilic Additions of endo-Tricyclo[5.2.1.0^(2,6)]deca-2(6),8-dien-3-one

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Chinese Chemical Letters 2001年第7期12卷 581-584页

Nucleophilic additions to endo-tricyclo[5.***.1.0^(2,6)]deca-2(6),8-dien-3-one 4 are described. Experimental results show high preference for exo-facial attack to the enone moiety of tricyclodecadienone. Steric hindrance is the main kinetically controlling factor in the nucleophilic reaction. The shielding effect and the stabilizing effect of the norbornene double bond favor the exo-facial attack also.

关键词： Stereochemistry nucleophilic addition