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Review of research on the mechanical properties of the human tooth

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International Journal of Oral Science 2014年第2期6卷 61-69页

作者： Ya-Rong Zhang wen du Xue-Dong Zhou Hai-Yang Yu State Key Laboratory of Oral Diseases West China Hospital of StomatologySichuan University

‘Bronze teeth＇ reflect the mechanical properties of natural teeth to a certain extent. Their mechanical properties resemble those of a tough metal, and the gradient of these properties lies in the direction from outside to inside. These attributes confer human teeth with effective mastication ability. Understanding the various mechanical properties of human teeth and dental materials is the basis for the development of restorative materials. In this study, the elastic properties, dynamic mechanical properties （visco-elasticity） and fracture mechanical properties of enamel and dentin were reviewed to provide a more thorough understanding of the mechanical properties of human teeth.

关键词： dentin enamel fatigue crack growth fracture toughness mechanical property

多信息自动闭塞列车速度-间隔控制模型及算法

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铁道学报 2000年第6期22卷 8-12页

作者：刘澜杜文西南交通大学交通运输学院，四川成都 610031

我国铁路在引进并运用先进的列车安全和运行控制系统 ,如以列车速度监督系统 (即 ATP系统 )为代表的多信息自动闭塞系统时 ,暴露出实际运用效果与理论计算值之间存在较大差异、理论和现场经验相矛盾等问题 ,其实质在于缺乏符合我国应用... 详细信息

我国铁路在引进并运用先进的列车安全和运行控制系统 ,如以列车速度监督系统 (即 ATP系统 )为代表的多信息自动闭塞系统时 ,暴露出实际运用效果与理论计算值之间存在较大差异、理论和现场经验相矛盾等问题 ,其实质在于缺乏符合我国应用实际的理论依据 ,对现场运用缺乏相应的理论指导。本文在简要分析多信息自动闭塞系统速度 -间隔理论的基础上 ,建立了列车速度 -间隔控制方案的优化模型 ,介绍了模型的求解和实用算法的构造并给出了算例。

关键词：多信息自动闭塞系统速度-间隔控制优化模型

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动态供应链重构的分形模式研究

北京工业大学学报 2006年第10期32卷 925-930页

作者：周建频杜文西南交通大学交通运输学院成都610031

为了提高供应链在不确定性环境下的适应能力、供应链重构的适应性和自动性,应用分形理论和人工智能方法,通过供应链实体与多代理系统之间的映射关系建立了供应链和资源代理的模块框架,提出了资源代理的分形模块与分形模式信息的动态对... 详细信息

为了提高供应链在不确定性环境下的适应能力、供应链重构的适应性和自动性,应用分形理论和人工智能方法,通过供应链实体与多代理系统之间的映射关系建立了供应链和资源代理的模块框架,提出了资源代理的分形模块与分形模式信息的动态对应关系．通过采用分层遗传算法、多目标优化、多重分形和供应链契约等方法,研究了基于分形模式的动态供应链自动重构过程,提出了动态供应链重构策略的自适应方法,分析了供应链重构的分形模式在汽车转向系统供应链资源框架中的应用。

关键词：供应链重构代理分形模块适应

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改革铁路运输产品计量方法的若干思考

西南交通大学学报 2000年第3期35卷 246-249页

作者：杜文任民西南交通大学交通运输学院四川成都610031 铁道部经济规划研究院北京100038

探讨了铁路运能与运量的统计方法 ,认为随着市场经济的发展 ,运输产品开始从数量到质量转变 ,铁路的运能和运量已逐渐转移到产品的结构、质量和价值之中。因此。

关键词：运能运量铁路运输产品计量方法结构质量

Recent advances in kinetic and thermodynamic regulation of magnesium hydride for hydrogen storage

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Rare Metals 2023年第9期42卷 2906-2927页

作者： Hang Yang Zhao Ding Yu-Ting Li Shao-Yuan Li Ping-Keng Wu Quan-Hui Hou Yang Zheng Biao Gao Kai-Fu Huo wen-Jia du Leon L.Shaw The State Key Laboratory of Refractories and Metallurgy Institute of Advanced Materials and NanotechnologyWuhan University of Science and TechnologyWuhan430081China College of Materials Science and Engineering National Engineering Research Center for Magnesium AlloysChongqing UniversityChongqing400044China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming650093China

Developing safer and more efficient hydrogen storage technology is a pivotal step to realizing the hydrogen economy. Owing to the lightweight, high hydrogen storage density and abundant reserves, MgH_(2) has been widely studied as one of the most promising solidstate hydrogen storage materials. However, defects such as stable thermodynamics, sluggish kinetics and rapid capacity decay have seriously hindered its practical application. This article reviews recent advances in catalyst doping and nanostructures for improved kinetic performance of MgH_(2)/Mg systems for hydrogen release/absorption, the tuning of their thermodynamic stability properties by alloying and reactant destabilization, and the dual thermodynamic and kinetic optimization of the MgH_(2)/Mg system achieved by nanoconfinement with in situ catalysis and ball milling with in situ aerosol spraying, aiming to open new perspectives for the scale-up of MgH_(2) for hydrogen storage applications.

关键词： Magnesium hydride Thermodynamics Kinetics Hydrogen storage

Appendicitis combined with Meckel’s diverticulum obstruction, perforation, and inflammation in children: Three case reports

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World Journal of Clinical Cases 2024年第4期12卷 865-871页

作者： Yi-Meng Sun Wang Xin Yu-Fang Liu Zhe-Ming Guan Hao-wen du Ning-Ning Sun Yong-Dong Liu School of Clinical Medicine Weifang Medical UniversityWeifang 261000Shandong ProvinceChina Department of Pediatric Surgery Weifang People’s HospitalWeifang 261000Shandong ProvinceChina Department of Burn Surgery Weifang People’s HospitalWeifang 261000Shandong ProvinceChina

BACKGROUND Meckel’s diverticulum is a common congenital malformation of the small intestine,with the three most common complications being obstruction,per-foration,and *** date,only a few cases have been reported *** children,the clinical symptoms are similar to *** most of the imaging features are nonspecific,the preoperative diagnosis is not *** addition,the clinical characteristics are highly similar to pediatric acute appendicitis,thus special attention is necessary to distinguish Meckel’s diver-ticulum from pediatric *** with poor disease control should undergo laparoscopic exploration to avoid serious complications,including intestinal necrosis,intestinal perforation and gastrointestinal *** SUMMARY This report presents three cases of appendicitis in children combined with intestinal obstruction,which was caused by fibrous bands(ligaments)arising from the top part of Meckel's diverticulum,diverticular perforation,and diver-ticular *** three patients,aged 11-12 years,had acute appendicitis as their initial clinical *** were treated by laparoscopic surgery with a favorable outcome.A complete dataset including clinical presentation,dia-gnostic imaging,surgical information,and histopathologic findings was also *** Preoperative diagnosis of Meckel’s diverticulum and its complications is challenging because its clinical signs and complications are similar to those of appendicitis in *** combined with laparotomy is useful for diagnosis and treatment.

关键词： Meckel’s diverticulum Complications Intestinal obstruction Perforation Appendicitis in children Mesodiverticular band Ligament Diverticular disease Case report

Typical Correlation Analysis between Forage Type Triticale Production Performance and Different Pilot Ecological Factors

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Journal of Botanical Research 2021年第1期3卷 46-51页

作者： Jing Liu wen-jun Tuo wen-hua du Jiu-li Wang School of Ecological Environment and Resource Qinghai Nationalities UniversityXining 810007China College of Pratacultural Science Gansu Agricultural UniversityXining 730070China

Domestic and foreign researches on triticale mainly focus on hereditary traits and excellent characteristics,but there are few reports on triticale yield and quality in the severe cold pastoral areas of Gansu and *** this study,Gannong 2 triticale cultivars have been bred and planted in typical ecological areas according to the characteristics of different ecological *** studying the relationship between quality traits and various ecological factors,the effects of different ecological factors on the quality of Triticale hay have been clarified,which provides a reasonable basis for future triticale breeding and large-scale and targeted planting *** production performance and nutritional qualities of Triticale Trial in Maqu County,Gansu Province and Gannong No.2 in dulan County,Qinghai Province are obviously superior to other pilot *** reasonable fertilization,the production performance and nutritional quality of triticale are the *** production performance is significantly related to climatic factors in different *** most suitable planting area for Gannong 2 is Maqu County,Gansu Province.

关键词： Triticale Production performance Nutritional qualities Ecological factors

Estimating light interception using the color attributes of digital images of cotton canopies

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Journal of Integrative Agriculture 2017年第7期16卷 1474-1485页

作者： XUE Hui-yun HAN Ying-chun LI Ya-bing WANG Guo-ping FENG Lu FAN Zheng-yi du wen-li YANG Bei-fang MAO Shu-chun Institute of Cotton Research Chinese Academy of Agricultural Sciences/State Key Laboratory of Cotton Biology Henan Collaborative Innovation Center of Modern Biological Breeding Henan Institute of Science and Technology

Crop growth and yield depend on canopy light interception （LI）. To identify a low-cost and relatively efficient index for measuring LI, several color attributes of red-green-blue （RGB）, hue-saturation-intensity （HSI）, hue-saturation-value （HSV） color models and the component values of color attributes in the RGB color model were investigated using digital images at six cotton plant population densities in 2012-2014. The results showed that the LI values followed downward quadratic curves after planting. The red （R）, green （G） and blue （B） values varied greatly over the years, in accordance with Cai＇s research demonstrating that the RGB model is affected by outside light. Quadratic curves were fit to these color attributes at six plant population densities. Additionally, linear regressions of LI on every color attribute revealed that the hue （H） values in HSI and HSV were significantly linearly correlated with LI with a determination coefficient （R2）〉0.89 and a root mean square error （RMSE）=0.05. Thus, the H values in the HSI and HSV models could be used to measure LI, and this hypothesis was validated. The H values are new indexes for quantitatively estimating the LI of heterogeneous crop cano- pies, which will provide a theoretical basis for optimizing the crop canopy structure. However, further research should be conducted in other crops and under other growing and environmental conditions to verify this finding.

关键词： canopy light interception (LI) digital image color attributes hue

基于色散光学模型的^(40)Ca核子散射数据计算

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物理学报 2023年第22期72卷 111-116页

作者：赵岫鸟杜文青渤海大学物理科学与技术学院锦州121013

对钙同位素核数据的研究具有重要的理论价值和应用前景,其中^(40)Ca作为天然钙最主要的同位素,是一种重要的材料核素.本文采用色散光学模型对球形核^(40)Ca的核子弹性散射数据进行计算.通过考虑色散光学模型势中实部势的非定域性以及虚... 详细信息

对钙同位素核数据的研究具有重要的理论价值和应用前景,其中^(40)Ca作为天然钙最主要的同位素,是一种重要的材料核素.本文采用色散光学模型对球形核^(40)Ca的核子弹性散射数据进行计算.通过考虑色散光学模型势中实部势的非定域性以及虚部势的壳间隙结构,实现了对^(40)Ca相关核子散射数据的良好描述,其中包括中子总截面、核子弹性散射角分布以及分析本领.此外,本文计算了色散光学模型势的实部体积分,其随能量的变化图像在费米能附近出现了明显的色散峰结构.

关键词：核子散射色散光学模型弹性散射