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Research on the quasi-isentropic driving model of aluminized explosives in the detonation wave propagation direction

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Defence Technology（防务技术） 2024年第2期32卷 596-618页

作者： Hongfu Wang Yan Liu Fan Bai Chao He Yingliang Xu Qiang zhou chuan Xiao Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Research and Development Academy of Machinery Equipment Beijing100089China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

Taking CL-20(Hexanitrohexaazaisowurtzitane)-based aluminized explosives with high gurney energy as the research object, this research experimentally investigates the work capability of different aluminized explosive formulations when driving metal flyer plates in the denotation wave propagation *** research results showed that the formulations with 43 μm aluminum(Al) powder particles(The particle sizes of Al powder were in the range of 2~43 μm) exhibited the optimal performance in driving flyer plates along the denotation wave propagation direction. Compared to the formulations with Al powder 13 μm, the formulations with Al powder 2 μm delivered better performance in accelerating metal flyer plates in the early stage, which, however, turned to be poor in the later stage. The CL-20-based explosives containing 25% Al far under-performed those containing 15% Al. Based on the proposed quasi-isentropic hypothesis, relevant isentropy theories, and the functional relationship between detonation parameters and entropy as well as Al reaction degree, the characteristic lines of aluminized explosives in accelerating flyer plates were theoretically studied, a quasi-isentropic theoretical model for the aluminized explosive driving the flyer plate was built and the calculation methods for the variations of flyer plate velocity, Al reaction degree, and detonation product parameters with time and axial positions were developed. The theoretical model built is verified by the experimental results of the CL-20-based aluminized explosive driving flyer plate. It was found that the model built could accurately calculate the variations of flyer plate velocity and Al reaction degree over time. In addition, how physical parameters including detonation product pressure and temperature varied with time and axial positions was identified. The action time of the positive pressure after the detonation of aluminized explosives was found prolonged and the downtrend of the temperature was

关键词： Aluminized explosive Flyer plate experiment Quasi-isentropic theoretical model Al reaction Driving characteristics

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In vitro Ruminal Gas Production Kinetics of Four Fodder Trees Ensiled With or Without Molasses and Urea

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Journal of Integrative Agriculture 2013年第7期12卷 1234-1242页

作者： Abdelfattah Z M Salem zhou chuan-she TAN Zhi-liang Miguel Mellado Moises Cipriano Salazar Mona M M Y Elghandopur Nicholas E Odongo Faculty of Veterinary and Livestock Autonomous University of the State of Mexico Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences Department of Animal Nutrition Autonomous Agrarian University Antonio Narro Faculty of Veterinary and Livestock Autonomous University of Guerrero

This study investigated if the addition of urea （U）, molasses （M） or their 1：1 （v/v） mixture during ensiling increases the nutritional value of forage from four fodder trees （Prunus persica, Leucaena esculenta, Acacia farnesiana, and Prunus domestica）. Forage samples of fodder trees were collected in triplicate （three individual samples of each species） and subjected to an in vitro gas production （GP） procedure. Fermentation at 24 h （GP 24）, short-chain volatile fatty acids （SCFA）, and microbial crude protein production （MCP）, in vitro organic matter digestibility （OMD）, metabolizable energy （ME） and dry matter degradability （DMD） were estimated. Forage samples were incubated for 72 h in an incubator at 39oC and the volume of GP was recorded at 2, 4, 6, 8, 10, 12, 24, 48, and 72 h of incubation using the reading pressure technique. The rumen fermentation profiles were highest for P. persica, which showed the highest （P〈0.0001） DMD, ME, OMD, SCFA, GP 24 and MCP. On the other hand L. esculenta had the lowest （P〈0.0001） DMD, SCFA, MCP; P. domestica had the lowest （P〈0.0001） OMD. The addition of M to silage increased （P〈0.0001） ME and OMD, as well as GP. However, the addition of U and the mixture of U and M reduced （P〈0.0001） DMD, ME, OMD, SCFA, GY 24 and MCP. These results show that P. persica has the highest nutritive value and L. esculenta the lowest for ruminants. Additionally, the addition of M to forage from fodder trees increases rumen GP and fermentation, which may improve nutrient utilization in ruminants.

关键词： fodder trees urea molasses gas production

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The cluster digging behavior of larvae confers trophic benefits to fitness in insects

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Insect Science 2024年第3期31卷 870-884页

作者： Yujie Wu Qiang Wang Weikang Yang Sheng Zhang chuan-Xi Mao Nana He Shaojie zhou chuanming zhou Wei Liu School of Plant Protection Anhui Agricultural UniversityAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Province Engineering Laboratory for Green Pesticide Development and ApplicationHefeiChina College of Plant Protection Nanjing Agricultural UniversityNanjingChina School of Teacher Education Nanjng Xiaozhuang UniversityNanjingChina State Key Laboratory of Biocatalysis and Enzyme Engineering Hubei Province Key Laboratory of Biotechnology of Chinese Traditional MedicineNational&Local Joint Engineering Research Center of High-throughput Drug Screening TechnologySchool of Life ScienceHubei UniversityWuhanChina

Collective behaviors efficiently impart benefits to a diversity of species ranging from bacteria to *** larvae tend to cluster and form coordinated digging groups under crowded conditions,yet understanding the rules governing this behavior is in its *** primarily took advantage of the Drosophila model to investigate cooperative foraging ***,we report that Drosophila-related species and the black soldier fly have evolved a conserved strategy of cluster digging in food ***,we investigated relative factors,including larval stage,population density,and food stiffness and quality,that affect the cluster digging ***,oxygen supply through the posterior breathing spiracles is necessary for the organization of digging *** importantly,we theoretically devise a mathematical model to accurately calculate how the cluster digging behavior expands food resources by diving depth,cross-section area,and food *** found that cluster digging behavior approximately increases 2.2 fold depth,1.7-fold cross-section area,and 1.9 fold volume than control groups,*** of food sources significantly facilitates survival,larval development,and reproductive success of Drosophila challenged with competition for limited food resources,thereby conferring trophic benefits to fitness in ***,our findings highlight that the cluster digging behavior is a pivotal behavior for their adaptation to food scarcity,advancing a better understanding of how this cooperative behavior confers fitness benefits in the animal kingdom.

关键词： cluster digging determinant development fecundity larvae mathematical model

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Dynamic stress concentrations in thick plates with two holes based on refined theory

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Applied Mathematics and Mechanics(English Edition) 2014年第12期35卷 1591-1606页

作者：周传平胡超 F.MA 刘殿魁 School of Mechanical Engineering Hangzhou Dianzi University College of Civil Science and Engineering Yangzhou University College of Engineering University of CaliforniaBerkeley 94720 U.S.A. College of Aerospace and Civil Engineering Harbin Engineering University

Based on complex variables and conformal mapping, the elastic wave scat- tering and dynamic stress concentrations in the plates with two holes are studied by the refined dynamic equation of plate bending. The problem to be solved is changed to a set of infinite algebraic equations by an orthogonM function expansion method. As examples, under free boundary conditions, the numerical results of the dynamic moment concen- tration factors in the plates with two circular holes are computed. The results indicate that the parameters such as the incident wave number, the thickness of plates, and the spacing between holes have great effects on the dynamic stress distributions. The results are accurate because the refined equation is derived without any engineering hypothese.

关键词： refined vibration equation complex variable and conformal mappingmethod two holes elastic wave scattering and dynamic stress concentrations thick plate

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基于灰色关联度的形态滤波及滚动轴承故障诊断中应用

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振动与冲击 2015年第14期34卷 51-55页

作者：文成周传德重庆科技学院机械与动力工程学院重庆401331

针对形态滤波中结构元素尺度难以确定问题,提出利用灰色关联度最大准则选择结构元素尺度进行形态滤波新方法。以不同尺度结构元素对信号进行形态滤波,计算滤波后信号与原信号灰色关联度,借助灰色关联度评价形态滤波质量,以灰色关联度最... 详细信息

针对形态滤波中结构元素尺度难以确定问题,提出利用灰色关联度最大准则选择结构元素尺度进行形态滤波新方法。以不同尺度结构元素对信号进行形态滤波,计算滤波后信号与原信号灰色关联度,借助灰色关联度评价形态滤波质量,以灰色关联度最大原则确定形态滤波所需结构元素尺度,获得特征信息。利用信号仿真分析实施过程,并用于滚动轴承故障诊断。实验结果表明,该方法能有效提取滚动轴承故障特征信息,实现故障诊断。

关键词：灰色关联度形态滤波结构元素滚动轴承故障诊断

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论鄂西土家族传统民居艺术的审美特色

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重庆建筑大学学报 2008年第1期30卷 13-16页

作者：周传发三峡大学艺术学院湖北宜昌443002

土家族是一个有着悠久历史和文化传统的民族,鄂西土家族传统民居艺术则是其民族文化的典型代表,它的外部造型与内部空间营建,以及对山地自然环境的充分适应与巧妙利用,不仅体现了实用与审美、建筑与场所的完美结合,而且反映了土家人对... 详细信息

土家族是一个有着悠久历史和文化传统的民族,鄂西土家族传统民居艺术则是其民族文化的典型代表,它的外部造型与内部空间营建,以及对山地自然环境的充分适应与巧妙利用,不仅体现了实用与审美、建筑与场所的完美结合,而且反映了土家人对于生活与美的理解。从鄂西土家民居的审美视角出发,通过对吊角楼建筑形态美学特征的研究和分析,试图揭示土家民居建筑中所蕴涵的深层次的文化底蕴和精神品质,吸取其设计精髓,为现代化建设服务。

关键词：土家族传统民居吊脚楼审美

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Model established based on blood markers predicts overall survival in patients after radical resection of types Ⅱ and Ⅲ adenocarcinoma of the esophagogastric junction

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World Journal of Gastrointestinal Surgery 2022年第8期14卷 788-798页

作者： Zhi-Jian Wei Ya-Ting Qiao Bai-chuan zhou Abigail N Rankine Li-Xiang Zhang Ye-zhou Su A-Man Xu Wen-Xiu Han Pan-Quan Luo Department of General Surgery The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Gastrointestinal Surgery Affiliated Hospital of HeBei UniversityBaoding 071000Hebei ProvinceChina Department of Clinical Medicine Anhui Medical UniversityHefei 230032Anhui ProvinceChina Department of Gastroenterology Anhui Provincial Key Laboratory of Digestive DiseaseThe First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Obstetrics and Gynecology The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina

BACKGROUND In recent years, the incidence of types Ⅱ and Ⅲ adenocarcinoma of the esophagogastric junction(AEG) has shown an obvious upward trend worldwide. The prognostic prediction after radical resection of AEG has not been well *** To establish a prognostic model for AEG(types II and III) based on routine *** A total of 355 patients who underwent curative AEG at The First Affiliated Hospital of Anhui Medical University from January 2014 to June 2015 were retrospectively included in this study. Univariate and multivariate analyses were performed to identify the independent risk factors. A nomogram was constructed based on Cox proportional hazards models. The new score models was analyzed by C index and calibration curves. The receiver operating characteristic(ROC) curve was used to compare the predictive accuracy of the scoring system and tumor-node-metastasis(TNM) stage. Overall survival was calculated using the Kaplan-Meier curve amongst different risk AEG *** Multivariate analysis showed that TNM stage(hazard ratio [HR] = 2.286, P = 0.008), neutrophil-tolymphocyte ratio(HR = 2.979, P = 0.001), and body mass index(HR = 0.626, P = 0.026) were independent prognostic factors. The new scoring system had a higher concordance index(0.697),and the calibration curves of the nomogram were reliable. The area under the ROC curve of the new score model(3-year: 0.725, 95% confidence interval [CI]: 0.676-0.777;5-year: 0.758, 95%CI:0.708-0.807) was larger than that of TNM staging(3-year: 0.630, 95%CI: 0.585-0.684;5-year: 0.665,95%CI: 0.616-0.715).CONCLUSION Based on the serum markers and other clinical indicators, we have developed a precise model to predict the prognosis of patients with AEG(types II and III). The new prognostic nomogram could effectively enhance the predictive value of the TNM staging system. This scoring system can be advantageous and helpful for surgeons and patients.

关键词： Adenocarcinomas of the esophagogastric junction Neutrophil-to-lymphocyte ratio Platelet-tolymphocyte ratio Prognosis Tumor-node-metastasis

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Initial detection of the quorum sensing autoinducer activity in the rumen of goats in vivo and in vitro

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Journal of Integrative Agriculture 2016年第10期15卷 2343-2352页

作者： RAN Tao zhou chuan-she XU Li-wei GENG Mei-mei TAN Zhi-liang TANG Shao-xun WANG Min HAN Xue-feng KANG Jin-he Key Laboratory for Agro-Ecological Processes in Subtropical Region/Hunan Research Center of Livestock & Poultry Sciences/ South-Central Experimental Station of Animal Nutrition and Feed Science Ministry of Agriculture/Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 P.R.China University of the Chinese Academy of Sciences Beijing 100049 P.R.China Hunan Co-Innovation Center of Animal Production Safety CICAPS Changsha 410128 P.R. China Hunan Co-Innovation Center for Utilization of Botanical Functional Ingredients Changsha 410128 P.R. China

Quorum sensing（QS） is a type of microbe-microbe communication system that is widespread among the microbial world, particularly among microorganisms that are symbiotic with plants and animals. Thereby, the cell-cell signalling is likely to occur in an anaerobic rumen environment, which is a complex microbial ecosystem. In this study, using six ruminally fistulated Liuyang black goats as experimental animals, we aimed to detect the activity of quorum sensing autoinducers（AI） both in vivo and in vitro and to clone the lux S gene that encoded autoinducer-2（AI-2） synthase of microbial samples that were collected from the rumen of goats. Neutral detergent fiber（NDF） and soluble starch were the two types of substrates that were used for in vitro fermentation. The fermented fluid samples were collected at 0, 2, 4, 6, 8, 12, 24, 36, and 48 h of incubation. The acyl-homoserine lactones（AHLs） activity was determined using gas chromatography-mass spectrometer（GC-MS） analysis. However, none of the rumen fluid extracts that were collected from the goat rumen showed the same or similar fragmentation pattern to AHLs standards. Meanwhile, the AI-2 activity, assayed using a Vibrio harveyi BB170 bioassay, was negative in all samples that were collected from the goat rumen and from in vitro fermentation fluids. Our results indicated that the activities of AHLs and AI-2 were not detected in the ruminal contents from six goats and in ruminal fluids obtained from in vitro fermentation at different sampling time-points. However, the homologues of lux S in Prevotella ruminicola were cloned from in vivo and in vitro ruminal fluids. We concluded that AHLs and AI-2 could not be detected in in vivo and in vitro ruminal fluids of goats using the current detection techniques under current dietary conditions. However, the microbes that inhabited the goat rumen had the potential ability to secrete AI-2 signaling molecules and to communicate with each other via AI-2-mediated QS because of the prese

关键词： quorum sensing AHLs AI-2 lux S rumen bacteria goat

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教学学术的实践属性及其可能的误区

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江苏高教 2023年第3期 14-20页

作者：周川苏州大学教育科学研究院江苏苏州215123

从20世纪90年代起,博耶提出了教学学术的理论,舒尔曼等人拓展了这一理论并强调教学学术的可视化、技术化,从而在高等教育领域掀起了一场方兴未艾的教学学术运动。教学学术本质上是行动研究,以高校专业教师为研究主体,在教学实践过程中进... 详细信息

从20世纪90年代起,博耶提出了教学学术的理论,舒尔曼等人拓展了这一理论并强调教学学术的可视化、技术化,从而在高等教育领域掀起了一场方兴未艾的教学学术运动。教学学术本质上是行动研究,以高校专业教师为研究主体,在教学实践过程中进行,以改进教学为根本出发点和归宿;实践性是其本质特征。教学学术具有多样化的成果形式,但任何成果归根结底都必须体现于教学效果。“唯论文”是教学学术的一大误区,教学学术评价中“唯论文”的危害远甚于科研评价的“唯论文”。

关键词：教学学术博耶舒尔曼行动研究 “唯论文”

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高等教育“教学成果”的本义与歧义

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高等教育研究 2023年第8期44卷 58-65页

作者：周川苏州大学教育学院江苏苏州215123

高校教学以高深知识为内容,以学生的发展为宗旨。高等教育“教学成果”理应是目标与结果的统一、师生双边主体作用的统一、短期效果与长期效果的统一、主观与客观的统一,归根结底应是教学与发展的统一,它只能由学生的发展来认定。由于... 详细信息

高校教学以高深知识为内容,以学生的发展为宗旨。高等教育“教学成果”理应是目标与结果的统一、师生双边主体作用的统一、短期效果与长期效果的统一、主观与客观的统一,归根结底应是教学与发展的统一,它只能由学生的发展来认定。由于高校教学目标具有模糊性和动态性,教学效果的载体形式异常复杂,评价主体的地位明显不对称,因此高等教育“教学成果”实际上处于“测不准”的状态,高等教育“教学成果奖”在实施过程中也就出现各种歧义。若高等教育“教学成果奖”所奖非所实,就可能助长虚饰浮夸之风,造成教学质量假象,并使“良心活”发生异化。为此,亟须对高等教育“教学成果”进行前提性反思和正当性审查。

关键词：高校教学教学成果教学成果奖 “测不准”

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