期刊文献+
共找到30,553篇文章
< 1 2 250 >
每页显示 20 50 100
Discussion on the Free Quenching Heat Treatment Process of Automotive Leaf Springs
1
作者 Xianfeng Xu 《Frontiers of Metallurgical Industry》 2024年第1期9-11,共3页
Free quenching of automotive leaf springs is a new technology that has gradually started to be applied in the industry in China in recent years.Only a few manufacturers are applying it in the industry.Through more tha... Free quenching of automotive leaf springs is a new technology that has gradually started to be applied in the industry in China in recent years.Only a few manufacturers are applying it in the industry.Through more than half a year of on-site practice,the changes in the hot forming of spring plates before free quenching have been explored,and finally a heat treatment process that meets the production requirements of our company has been developed,achieving normal production. 展开更多
关键词 automotive leaf springs free quenching heat treatment TECHNOLOGY
下载PDF
Studies on the Characteristics of Nitrogen and Phosphorus Pollution of Natural Outcrop Springs in Wudalianchi
2
作者 魏晓雪 李月兴 +4 位作者 王菁华 方振兴 潘虹 曾颖 杨臣 《Agricultural Science & Technology》 CAS 2015年第5期1019-1022,共4页
Objective] The research aimed to study the characteristics of nitrogen and phosphorus pollution of 30 natural outcrop springs in Wudalianchi, which provides a theoretical basis for the sustainable development and util... Objective] The research aimed to study the characteristics of nitrogen and phosphorus pollution of 30 natural outcrop springs in Wudalianchi, which provides a theoretical basis for the sustainable development and utilization and protection of Wudalianchi natural mineral resources. [Method] Choosing the 30 natural outcrop spring representatives in different regions, samples were collected in low water period, normal water period, wet period respectively, and the content of nitrogen, phosphorus and other contaminants in the samples were determined. Besides, the pollution characteristics of nitrogen and phosphorus in Wudalianchi natural outcrop spring were analyzed. [Result] The 30 natural outcrop spring in Wudalianchi area were seriously polluted by nitrogen. Total nitrogen and nitrate nitrogen were the main forms of nitrogen pollution. The content of total phosphorus and ammonia nitrogen were low. [Conclusion] The natural outcrop spring is mainly caused by agricultural non-point source pollution. 展开更多
关键词 WUDALIANCHI springs Nitrogen and phosphorus pollution
下载PDF
Exploitation and Sustainable Development of Hot Springs in Xinjiang Province of China——A Case Study of Shawan Hot Spring Tourist Area
3
作者 张滢 《Journal of Landscape Research》 2011年第10期36-39,43,共5页
The paper had introduced geographic causes and types of hot springs, illustrated its disease-treating function and displayed its great vitality and widespread development prospect as tourist resources. By taking Shawa... The paper had introduced geographic causes and types of hot springs, illustrated its disease-treating function and displayed its great vitality and widespread development prospect as tourist resources. By taking Shawan Hot Spring in Xinjiang for example, the paper had analyzed its natural condition, hot springs and tourist economic development. And then, quantitative and qualitative analysis had been conducted on the quality of water environment resources in the research area. It had analyzed reasons for degeneration of water environment and studied exploitation and sustainable development of hot springs. It was considered that environment especially water environment quality had decreased since hot spring tourism development. In order to achieve sustainable development of hot springs and promotion of local tourism, it must be guided by environment treatment, and some strategies for sustainable development of hot springs had been proposed. 展开更多
关键词 HOT springs EXPLOITATION SUSTAINABLE development
下载PDF
基于SpringBoot框架的智慧校园管理系统设计与实现 被引量:2
4
作者 刘霞 《长江信息通信》 2024年第2期148-150,共3页
随着国家《智慧校园总体框架》的提出,各职业院校纷纷启动了智慧校园的建设,因学校发展实际情况、重视程度、资金投入等不同,智慧校园建设的步伐也不一致。文章分析了智慧校园管理系统需求,提出基于Spring Boot框架,整合MyBatis数据持... 随着国家《智慧校园总体框架》的提出,各职业院校纷纷启动了智慧校园的建设,因学校发展实际情况、重视程度、资金投入等不同,智慧校园建设的步伐也不一致。文章分析了智慧校园管理系统需求,提出基于Spring Boot框架,整合MyBatis数据持久化框架,数据库选择高性能的MySQL,内存数据库采用Redis缓存技术,采用前后端分离模式设计,前端采用Vue.js、Element-UI、Axios来实现前后端数据交互的系统设计方案和实现过程,为智慧校园的建设提供一种可行的方案参考。 展开更多
关键词 spring Boot 智慧校园 管理系统
下载PDF
概念、视角、叙述与古代中国墓葬美术史书写——巫鸿The Art of the Yellow Springs:Understanding Chinese Tombs评述 被引量:4
5
作者 刘晓达 《广东第二师范学院学报》 2012年第1期106-112,共7页
在大量美术考古材料不断出土的情况下,新方法、新视角以及由此衍生出的一些重要的学术概念,构成了最近30年来古代中国墓葬美术史研究的总体特征。如空间性、物质性、时间性这三个学术概念就建构了巫鸿新作《黄泉下的美术——宏观中国古... 在大量美术考古材料不断出土的情况下,新方法、新视角以及由此衍生出的一些重要的学术概念,构成了最近30年来古代中国墓葬美术史研究的总体特征。如空间性、物质性、时间性这三个学术概念就建构了巫鸿新作《黄泉下的美术——宏观中国古代墓葬》的研究线索,也体现出作者希望以提出若干重要学术概念为依托,重新思考古代中国墓葬美术发展的内在理路。同时所呈现出的叙述与分析风格及美术史观,相对于传统的中国美术通史叙述方式,则具有更为宽广的学术视野。这些特征都为以后的古代中国墓葬美术史研究,提供了一个可以继续探索的桥梁。 展开更多
关键词 中国墓葬美术史 巫鸿 《黄泉下的美术》 学术概念 叙述框架
下载PDF
基于SpringSide的可定制数据采集系统的设计与实现 被引量:3
6
作者 廖宁 李振坤 邓钊汉 《计算机技术与发展》 2009年第10期234-237,共4页
当前计算机信息系统的根本出发点之一就是获取资源数据,而这些资源数据大多数都是非常灵活、多样的。为了适应待采集资源数据的多样性和灵活性,提出了一种采用可扩展架构技术,基于SpringSide架构的可定制资源数据采集系统的设计方案,介... 当前计算机信息系统的根本出发点之一就是获取资源数据,而这些资源数据大多数都是非常灵活、多样的。为了适应待采集资源数据的多样性和灵活性,提出了一种采用可扩展架构技术,基于SpringSide架构的可定制资源数据采集系统的设计方案,介绍了该系统的数据库设计以及主要功能设计,以该系统其中一个小模块为例详细说明了在SpringSide架构下系统的实现过程。该设计方案已经应用在实际项目——E平台实验动物资源库中,投入使用后的实际效果良好,并具有良好的灵活性、可扩展性和可维护性。 展开更多
关键词 springside 可定制 MVC spring STRUTS HIBERNATE
下载PDF
基于Spring Boot的产教联合体信息平台设计
7
作者 刁建忠 许志伟 伍嘉华 《科技创新与应用》 2024年第14期28-31,共4页
该文设计基于B/S架构的联合体信息平台,利用Spring Boot、MyBatis Plus、Vue等优秀框架实现高效的开发,集成Spring Security和JWT令牌机制,完成认证和权限控制。同时整合Redis缓存,将热点资源缓存至内存中,以实现快速查询操作,从而减轻M... 该文设计基于B/S架构的联合体信息平台,利用Spring Boot、MyBatis Plus、Vue等优秀框架实现高效的开发,集成Spring Security和JWT令牌机制,完成认证和权限控制。同时整合Redis缓存,将热点资源缓存至内存中,以实现快速查询操作,从而减轻MySQL数据库的负载压力。该系统稳定、兼容性强,能使联合体成员沟通更方便、信息的发布和维护的效率更高,实现人才共育共享。 展开更多
关键词 spring Boot MyBatis Vue 产教联合体信息平台 B/S架构
下载PDF
基于SpringSide的安全框架的应用与扩展 被引量:5
8
作者 于增光 刘竹松 《现代计算机》 2010年第7期210-212,共3页
分析基于SpringSide的安全框架,主要说明如何在SpringSide框架下对资源进行认证和授权,进一步通过对SpringSecurity2.0的扩展,实现直接从数据库读取权限,增强控制资源的灵活性。并结合一个网络实验动物资源库平台的开发,对该框架安全性... 分析基于SpringSide的安全框架,主要说明如何在SpringSide框架下对资源进行认证和授权,进一步通过对SpringSecurity2.0的扩展,实现直接从数据库读取权限,增强控制资源的灵活性。并结合一个网络实验动物资源库平台的开发,对该框架安全性进行分析。 展开更多
关键词 springside spring SECURITY 安全框架
下载PDF
澳大利亚Alice Springs造山带北缘构造变形序列与伟晶岩成矿 被引量:1
9
作者 彭玉恒 苏君 季建清 《地质科学》 CAS CSCD 北大核心 2021年第3期972-984,共13页
澳大利亚北领地南部具有近平行展布的线性沉积盆地及隆起的变质地层相间排列的特征。这种独特构造格局的形成与新元古代晚期到古生代中期的两次板内造山事件有关。研究区主要受第二次板内造山事件,即Alice Springs造山活动影响。对研究... 澳大利亚北领地南部具有近平行展布的线性沉积盆地及隆起的变质地层相间排列的特征。这种独特构造格局的形成与新元古代晚期到古生代中期的两次板内造山事件有关。研究区主要受第二次板内造山事件,即Alice Springs造山活动影响。对研究区进行地质调查和填图工作后得到以下认识:1)区域经历了3个期次的构造活动,前两期活动伴随着花岗伟晶岩的侵位;2)变形深度逐渐变浅,主应力轴分别为前两期的近南北向和第三期的北西—南东向;3)研究区的花岗伟晶岩主要由常见的造岩矿物构成,呈平缓的席状侵位特征,并未发育与围岩相同的剪切面理,也没有出现由结晶分异导致的分带现象,因此推测其成矿潜力较小。 展开更多
关键词 北领地 Alice springs造山运动 构造期次 伟晶岩成矿
下载PDF
基于Spring Boot+Vue框架的羊场综合 管理系统软件的设计与应用 被引量:3
10
作者 姜韶华 常星海 +5 位作者 高云帆 南风 马东 李书琴 陈玉林 张恩平 《家畜生态学报》 北大核心 2024年第3期55-62,共8页
本研究旨在辅助羊场生产数据规范化管理及良种繁育智能科学化应用,采用MySQL数据库及Java、R编程语言,基于Spring Boot+Vue框架设计了一套羊场综合管理系统软件。该系统优化了羊只信息管理、羊场配种方案,实现生产数据可视化,设置预警... 本研究旨在辅助羊场生产数据规范化管理及良种繁育智能科学化应用,采用MySQL数据库及Java、R编程语言,基于Spring Boot+Vue框架设计了一套羊场综合管理系统软件。该系统优化了羊只信息管理、羊场配种方案,实现生产数据可视化,设置预警功能帮助羊场及时掌握羊只产羔时间与生产性能情况;系统设计羊只基本信息管理、生产信息、疫病信息、繁殖信息、药品管理、饲料管理、统计报表与预警、科学育种八个模块。其中,在科学育种管理子模块中,根据羊场育种需求,构建了三种育种值计算模型(BLUP模型、GLMM模型、平均表现型模型),结合种公母羊实际表现,实现种公母羊的等级排序并自动生成近交系数,得到科学合理的配种方案。本系统在陕北某集约化肉羊场、横山区某绒山羊养殖联合育种户、富平县某奶山羊养殖场进行为期半年的实际生产应用,通过跟踪核心群体,完善与优化系统各项功能,为羊场智慧化、数字化育种管理提供了数据平台,同时也为实现智慧羊场的发展增添了新版本1.0。 展开更多
关键词 spring Boot+Vue框架 羊场 信息管理系统 育种
下载PDF
基于Vue.js与Spring Boot的教务管理系统设计
11
作者 谢振华 《电脑与信息技术》 2024年第4期95-97,101,共4页
随着Web应用开发技术的不断发展,采用传统Web技术开发的教务管理系统越来越难满足实际需求,在此背景下,提出了一种同时基于Vue.js与Spring Boot的教务管理系统设计与实现方案。该系统采用Vue.js框架作为前端开发框架,实现了前台页面的... 随着Web应用开发技术的不断发展,采用传统Web技术开发的教务管理系统越来越难满足实际需求,在此背景下,提出了一种同时基于Vue.js与Spring Boot的教务管理系统设计与实现方案。该系统采用Vue.js框架作为前端开发框架,实现了前台页面的交互和后台数据展示。同时,使用Spring Boot作为后端框架,提供了稳定的数据请求和数据存储功能。阐述了系统的架构设计、技术实现和功能需求设计等方面内容。该设计方案,使系统具有速度快、效率高、稳定性强等优点,带来良好的用户体验,同时能够满足教务管理的需要。采用该架构设计的系统同时也具有很好的可扩展性和可移植性,方便学校进行二次开发和部署。 展开更多
关键词 Vue.js spring Boot 教务管理系统
下载PDF
Influence of the Chuxiong Yao'an Earthquake on the Mineralization of Hot Springs in the Tengchong Geothermal Area,Southwestern China 被引量:6
12
作者 DENG Jun XIAO Changhao +4 位作者 WANG Qingfei ZHOU Xingzhi YANG Liqiang ZHANG Jing ZHAO Yan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第6期1391-1400,共10页
The Tengchong geothermal area,an active tectonic region with frequent earthquakes,is located in Yunnan Province of southwestern China.This area contains abundant active hot springs, which often display high metal conc... The Tengchong geothermal area,an active tectonic region with frequent earthquakes,is located in Yunnan Province of southwestern China.This area contains abundant active hot springs, which often display high metal concentrations and obvious mineralization phenomena.At 19:19 on 9 July 2009,an earthquake occurred in Yao'an,Chuxiong,Yunnan Province,which is 300 km to the northeast of the Tengchong geothermal area.We sampled water in the hot springs in the Tengchong area from 4 July to 9 July 2009 and from 10 July to 15 July 2009 to study the changes of elemental concentrations before and after the earthquake and discuss the influence of the earthquake on the mineralization of the hot springs.The concentrations of most trace elements increased slightly,but the concentration of REE(rare earth elements) decreased by 50%after the earthquake in the hot springs around a NS-trending fault.The elemental concentrations remained unchanged in Longtan and Suanshuigou,which are related to an inactive crater.The elemental concentrations in other springs controlled by superficial and small-scale faults decreased after the earthquake.The earthquake can stimulate the activity of deep faults and magma chambers,as is responsible for the increase of metal concentrations in the hot springs along the NS-trending deep fault;whereas it can decrease the porosity of permeable rocks,resulting in the decline of the flux of ore-bearing fluids and the corresponding mineralization in the hot springs related to superficial faults. 展开更多
关键词 hot springs EARTHQUAKE MINERALIZATION Tengchong REHAI
下载PDF
Design and Modeling on Stranded Wires Helical Springs 被引量:8
13
作者 ZHOU Jie WANG Shilong +1 位作者 KANG Ling CHEN Tianyi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第4期626-637,共12页
A stranded wires helical spring is formed of a multilayer and coaxial strand of several wires twisted together with the same direction of spiral. Compared with the conventional single wire spring, the stranded wires h... A stranded wires helical spring is formed of a multilayer and coaxial strand of several wires twisted together with the same direction of spiral. Compared with the conventional single wire spring, the stranded wires helical spring has the notable predominance in strength, damping and vibration reduction, which is usually used in aircraft engines, automatic weapons, etc. However, due to its complicated structure, the precise computation of its strength and rigidity need be a correct mathematical model, which then will be imported to finite element analysis software for solutions. Equations on solving geometric parameters, such as external diameters of strands and screw pitches of wires, are put forward in the paper. It also proposes a novel methodology on solving geometric parameters and establishing entity models of the stranded wires helical spring, which provides foundation of computing mechanical parameters by FEA. Then mathematical models on the centre line of the strand and the surface curve of each wire, after closing two ends in a spring, are proposed. Finally, geometric parameters are solved in a case study, and a 3D entity model of a spring with 3 layers and 16 wires is established, which has validated the accuracy of the proposed methodology and the 3D entity mathematical model. The method provides a new way to design stranded wire helical spring. 展开更多
关键词 stranded wires helical spring mathematical model finite element analysis closing ends
下载PDF
Three-stage Method for Identifying the Dynamic Model Parameters of Stranded Wire Helical Springs 被引量:5
14
作者 ZHAO Yu WANG Shilong +2 位作者 ZHOU Jie LI Chuan SUN Shouli 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第1期197-207,共11页
The dynamic behavior of the stranded wire helical spring is described by a modified Bouc-Wen model while the model parameters must be identified using an identification method and experimental data. Existing identific... The dynamic behavior of the stranded wire helical spring is described by a modified Bouc-Wen model while the model parameters must be identified using an identification method and experimental data. Existing identification methods usually relies either solely nonlinear iterative algorithms or manually trial and error. Therefore, the identification process can be rather time consuming and effort taking. As a result, these methods are not ideal for engineering applications. To come up with a more practical method, a three-stage identification method is proposed. Periodic loading and identification simulations are carried out to verify the effectiveness of the proposed method. Noises are added to the simulated data to test the performance of the proposed method when dealing with noise contaminated data. The simulation results indicate that the proposed method is able to give satisfying results when the noise levels are set to be 0.01, 0.03, 0.05 and 0.07. In addition, the proposed method is also applied to experimental data and compared with an existing method. The experimental data is acquired through a periodic loading test. The experiment results suggest that the proposed method features better accuracy compared with the existing method. An effective approach is proposed for identifying the model parameters of the stranded wire helical spring. 展开更多
关键词 Stranded wire helical spring modified Bouc-Wen model parameter identification OPTIMIZATION
下载PDF
Microbial diversity in two cold springs on the Qinghai-Tibetan Plateau 被引量:3
15
作者 Gaoyuan Li Hongchen Jiang +5 位作者 Weiguo Hou Shang Wang Liuqin Huang Huilei Ren Shicai Deng Hailiang Dong 《Geoscience Frontiers》 SCIE CAS 2012年第3期317-325,共9页
The microbial diversity in Wuli Area, Qinghai-Tibetan Plateau was investigated using 16S rRNA gene phylogenetic analyses. A total of 117 bacterial and 66 archaeal 16S rRNA gene clones were obtained from the Wuli cold ... The microbial diversity in Wuli Area, Qinghai-Tibetan Plateau was investigated using 16S rRNA gene phylogenetic analyses. A total of 117 bacterial and 66 archaeal 16S rRNA gene clones were obtained from the Wuli cold springs, The bacterial clones could be classified into Proteobacteria, Acid- obacteria, Deinococci, Sphingobacteria, Flavobacteria, Nitrospirae, Actinobacteria, Gemmatimona- detes, and unclassified-bacteria; and the archaeal clones could be classified into Crenarchaeota and Thaumarchaeota. Among the major groups, Proteobacteria and Crenarchaeota were dominant in the bacterial and archaeal 16S rRNA gene clone libraries, respectively. The clone sequences obtained in Wuli cold springs were closely related to those from cold habitats, such as snow/ice/soils on high mountains or at high latitude. Especially, the microbial community composition of Wuli Area was more similar to that in Tibetan glaciers than cold environments of other locations. The data presented in this study have impli- cations for a better understanding of microbial diversity in cold springs on the Qinghai-Tibetan Plateau. 展开更多
关键词 Cold spring Microbial diversity Qinghai-Tibetan Plateau
下载PDF
FORMULATION AND EVALUATION OF AN ANALYTICAL STUDY FOR CYLINDRICAL HELICAL SPRINGS 被引量:2
16
作者 Aimin Yu Changjin Yang 《Acta Mechanica Solida Sinica》 SCIE EI 2010年第1期85-94,共10页
The free vibration analysis of cylindrical helical springs is carried out by means of an analytical study. In the governing equations of the motion of the springs, all displacement functions are defined at the centroi... The free vibration analysis of cylindrical helical springs is carried out by means of an analytical study. In the governing equations of the motion of the springs, all displacement functions are defined at the centroid axis and also the effects of the rotational inertia, axial and shear deformations are included in the proposed model. Explicit analytical expressions which give the vibrating mode shapes are derived by rigorous application of the symbolic computing package MATHEMATICA and a process of searching is used to determine the exact natural frequencies. Numerical examples are provided for fixed-fixed boundary conditions. The free vibrational pa- rameters are chosen as the number of coils (n = 4- 14), the helix pitch angle (a = 5 - 30°) and as the ratio of the diameters of the cylinder and the wire (D/d = 4 - 18) in a wide range. Validation of the proposed model has been achieved through comparison with a finite element model using two-node standard beam elements and the results available in published literature, which in these cases indicates a very good correlation. 展开更多
关键词 cylindrical helical spring free vibration FREQUENCY mode shape
下载PDF
A discussion of up-flow springs 被引量:1
17
作者 ZHOU Xun WANG Xiao-cui +7 位作者 CAO Qin LONG Mi ZHENG Yu-hui GUO Juan SHEN Xiao-wei ZHANG Yu-qi TA Ming-ming CUI Xiang-fei 《Journal of Groundwater Science and Engineering》 2016年第4期279-283,共5页
Based on their genesis, springs are commonly classified as depression spring, contact spring, overflow spring and fault spring, etc. In addition, a kind of springs, i.e., up-flow spring, can be found in the field. An ... Based on their genesis, springs are commonly classified as depression spring, contact spring, overflow spring and fault spring, etc. In addition, a kind of springs, i.e., up-flow spring, can be found in the field. An aquifer is overlain by poorly-permeable unconsolidated sediments or relatively impervious formations. If the hydraulic head of the aquifer is higher than the land surface, groundwater may flow up to the ground surface through the local portion of the overlying aquicludes where the permeability is relatively good, and emerges as an up-flow spring. The common characteristics of an up-flow spring are discussed and summarized in this paper, and some examples of the up-flow springs are also given. Up-flow springs can flow up through local permeable zones in the overlying aquicludes rather than permeable faults. Although they cannot be found as frequently as depression springs, contact springs, overflow springs and fault springs etc., yet up-flow springs may occur in the form of normal-temperature springs, hot springs and salt springs. 展开更多
关键词 spring Hot spring Salt spring GROUNDWATER GENESIS
下载PDF
Microbial Mats in Tibetan Hot Springs and their Contributions to the Cesium-bearing Geyserite Ore Formation 被引量:2
18
作者 WANG Hailei ZHENG Mianping KONG Fanjing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第1期166-173,共8页
Microbial mats, mainly dominated by filamentous algae Calothrix and Oscillatoria, are well developed in Tibetan hot springs. A great number of fossil microorganisms, which existed as algae lamination in thermal deposi... Microbial mats, mainly dominated by filamentous algae Calothrix and Oscillatoria, are well developed in Tibetan hot springs. A great number of fossil microorganisms, which existed as algae lamination in thermal depositional cesium-bearing geyserite in this area, are identified as Calothrix and Oscillatoria through microexamination and culture experiments. These microbial mats show the ability to accumulate cesium from spring water to the extent of cesium concentration of 0.46-1.03% cell dry weight, 900 times higher than that in water, and capture large numbers of cesium-bearing opal grain. Silicon dioxide colloid in spring water replaces and fills with the organism and deposits on it to form algae laminated geyserite after dehydration and congelation. Cesium in the microbial mats and opal grain is then reserved in the geyserite. Eventually, cesium-bearing algae laminated geyserite is formed. Study on cesium distribution in geyserite also shows that cesium content in algae lamination, especially in heavily compacted algae lamination, is higher than in the opal layer. For geyserite with no algae lamination or other organism structure, which is generally formed in spring water with low silicon content, cesium accumulation and cesium-bearing opal grain assembled by the microbial mats are also indispensable. After the microbial mats accumulating cesium from spring water, silicon dioxide colloid poorly replaces and fills with the organism to form opal grain-bearing tremellose microbial mats. The shape and structure of the organisms are then destroyed, resulting in cesium-bearing geyserite with no algae lamination structure after dehydration and congelation. It is then concluded that microbial mats in the spring area contribute to the enrichment of cesium in the formation of cesium-bearing geyserite, and a biological genesis of the geyserite, besides of the physical and chemical genesis, is likely. 展开更多
关键词 microbial mats cesium-bearing geyserite algae lamination biological genesis Tibetan hot spring
下载PDF
ANALYSIS OF SPATIAL COMPLIANCE BEHAVIOR OF COILED SPRINGS VIA SCREW THEORY 被引量:1
19
作者 Ding XilunRobotics Research Institute, Beijing University of Aeronautics and Astronautics,Beijing 100083, ChinaSelig J M South Bank University, UK 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第4期293-297,318,共6页
A new method is presented to describe and analyze the spatial compliance ofcoiled springs using screw theory. After an abbreviated description for the deformation of a beamelement using screw theory, the spatial compl... A new method is presented to describe and analyze the spatial compliance ofcoiled springs using screw theory. After an abbreviated description for the deformation of a beamelement using screw theory, the spatial compliance density for a beam element is derived based onthe fundamental material theory and reasonable assumptions, and the spatial compliance of the beamwith finite length is obtained by integral. The spatial compliance of coiled springs is furtheranalyzed using the spatial compliance density of the beam element. By calculating theeigencompliance and Ball's principle screws for the whole compliance of system, the complianceproperties varying with the basic physical parameters of the system are illustrated in detail. Thebasic ideas can be used for the design and application of the coiled springs and the other compliantmechanisms with spatial compliant beam element. 展开更多
关键词 eigencompliance coiled springs screw theory MECHANISMS
下载PDF
Distribution of glycerol dialkyl glycerol tetraethers in Tibetan hot springs 被引量:2
20
作者 Liu He Chuanlun L.Zhang +2 位作者 Hailiang Dong Bin Fang Genhou Wang 《Geoscience Frontiers》 SCIE CAS 2012年第3期289-300,共12页
Isoprenoidal glycerol dialkyl glycerol tetraethers (iGDGTs) from the Gulu hot springs (23--83.6 ℃, pH 〉 7) and Yangbajing hot springs (80-128 ℃, pH 〉 7) were analyzed in order to investigate the distribution... Isoprenoidal glycerol dialkyl glycerol tetraethers (iGDGTs) from the Gulu hot springs (23--83.6 ℃, pH 〉 7) and Yangbajing hot springs (80-128 ℃, pH 〉 7) were analyzed in order to investigate the distribution of archaeal lipids among different hot springs in Tibet. A soil sample from Gulu was incubated at different temperatures and analyzed for changes in iGDGTs to help evaluate whether surrounding soil may contribute to the iGDGTs in hot springs. The sources of bacterial GDGTs (bGDGTs) in these hot springs were also investigated. The results revealed different profiles ofiGDGTs between Gulu and Yangbajing hot springs. Core iGDGTs and polar iGDGTs also presented different patterns in each hot spring. The PCA analysis showed that the structure of polar iGDGTs can be explained by three factors and suggested multiple sources of these compounds. Bivariate correlation analysis showed significant positive correlations between polar and core bGDGTs, suggesting the in situ production of bGDGTs in the hot springs. Furthermore, in the soil incubation experiment, temperature had the most significant influence on concentration of bGDGTs rather than iGDGTs, and polar bGDGTs had greater variability than core bGDGTs with changing temperature. Our results indicated that soil input had little influence on the composition of GDGTs in Tibetan hot springs. 展开更多
关键词 Glycerol dialkyl glyceroltetraethers (GDGTs) TIBET Hot springs Branched and isoprenoidtetraethers (BITs) TEX86
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部