检索结果-南通市图书馆

Magnetic and Magneto-Optical Properties in Paramagnetic NdF3 Under High Magnetic Field

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2005年第5期43卷 948-952页

作者： wangwei LIUGong-Qiang DepartmentofPhysics ShanghaiJiaoTongUniversityShanghai200240China DepartmentofPhysics ShanghaiJiaoTongUniversityShanghai200240China／／CCAST（WorldLaboratory）P.O.Box8730Beijing100080China

In this paper, we first theoretically report the magnetic and magneto-opticalproperties in paramagnetic media under high external magnetic field. Considering the action of theexternal magnetic Geld H_e and indirect exchange interaction H_v, the characteristic of the magneticsaturation and the property of the Faraday rotation to be nonlinear with external magnetic Geld arepresented in paramagnetic NdF_3. In terms of our theory, the indirect exchange interaction plays auimportant role in the magnetization M and the Faraday rotation θ in NdF_3 under high externalmagnetic Geld. The theory is in good agreement with experimental results. On the other hand, areasonable explanation for the temperature dependence of the ratio of the Verdet constant to themagnetic susceptibility V/x is obtained.

关键词： magneto-optical property verdet constant exchange interaction highmagnetic field nonlinear

在线全文

学校读者我要写书评

暂无评论

面向涂层裂纹的激光熔覆预测模型研究

热加工工艺 2024年第14期53卷 27-32页

作者：周浩南孙文磊王伟张志虎新疆大学机械工程学院新疆乌鲁木齐830047

针对激光熔覆关键工艺参数与制备涂层之间因存在复杂非线性映射关系而产生的裂纹缺陷问题,通过将遗传算法与BP神经网络结合起来构建工艺参数与涂层裂纹密度之间的网络模型,利用MATLAB软件对建立的网络模型进行训练、拟合预测。结果表明... 详细信息

针对激光熔覆关键工艺参数与制备涂层之间因存在复杂非线性映射关系而产生的裂纹缺陷问题,通过将遗传算法与BP神经网络结合起来构建工艺参数与涂层裂纹密度之间的网络模型,利用MATLAB软件对建立的网络模型进行训练、拟合预测。结果表明,遗传算法对BP神经网络优化后的模型中预测误差最小为3.06%,平均误差控制在11.57%以内,均方误差为0.0008,模型预测精度高,性能稳定。验证了理论模型与实际试验相结合的可行性,减少了涂层裂纹工艺研究所需的大量重复性试验,为制备无裂纹镍基熔覆层具有重要意义。

关键词：激光熔覆裂纹密度神经网络遗传算法模型预测

颗粒尺度和等离子喷涂工艺对涂层结构及结合强度的影响

在线全文

学校读者我要写书评

暂无评论

热加工工艺 2024年第14期53卷 16-20,26页

作者：杨浩王伟张山林杨平李成新西安交通大学材料科学与工程学院陕西西安710049 陕西斯瑞新材料股份有限公司陕西西安710077

采用等离子喷涂技术在T2纯铜基体上制备Fe_(3)O_(4)陶瓷涂层,研究了粉末颗粒尺度、等离子气氛、载气以及喷涂功率对涂层相结构、微观结构、硬度及结合强度的影响。结果表明,随颗粒尺度的增大,涂层相结构逐渐稳定;Ar-N_(2)等离子气氛下... 详细信息

采用等离子喷涂技术在T2纯铜基体上制备Fe_(3)O_(4)陶瓷涂层,研究了粉末颗粒尺度、等离子气氛、载气以及喷涂功率对涂层相结构、微观结构、硬度及结合强度的影响。结果表明,随颗粒尺度的增大,涂层相结构逐渐稳定;Ar-N_(2)等离子气氛下涂层致密度较高且相结构稳定。随喷涂功率的升高,大尺度颗粒制备的涂层硬度先增大后减小,载气为N_(2)时结合强度逐渐增大,载气为O_(2)时结合强度先增大后减小;喷涂条件相同时,O_(2)为载气制备的涂层硬度较高,N_(2)为载气制备的涂层结合强度较高;颗粒尺度>50μm的Fe_(3)O_(4)粉末,在Ar-N_(2)等离子气氛下以O_(2)为载气制备的涂层拥有最佳的综合性能,且涂层致密度可通过喷涂工艺调控。

关键词：等离子喷涂 Fe_(3)O_(4) 相结构微观结构结合强度

Tau Leptonic Decay τ→lVlVτ in Littlest Higgs Model＊

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2004年第2X期42卷 253-256页

作者： YUEChong-Xing wangwei DepartmentofPhysics LiaoningNormalUniversityDalian116029China

We consider the T leptonic decay τ→lVlVτ in the framework of the littlest Higgs (LH) model and calculate the corrections of new particles to this decay. We find that the contributions of the charged scalars can be safely ignored and the LH model is in perfect agreement with the universality of the couplings of the SU gauge bosons to the leptonic charged currents. The corrections of the LH model to the T leptonic decay τ→lVlVτ are not sensitive to the parameter c, but depend strongly on the parameters f and x. The precision measured data about the T leptonic decay demand that the parameter f approximately equal 3.5 TeV and x > 0.1, while agree with the general expectation based on other phenomenological explorations.

关键词： τ轻子衰减希格斯介子模型高能物理学标准玻色子弱电子对称破裂

TRIZ TECHNOLOGY FORECASTING AS QFD INPUT WITHIN THE NPD ACTIVITIES

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2004年第2期17卷 284-288页

作者： CoulibalySolomani HuaZhongsheng ShiQin wangwei DepartmentofManagementScience UniversityofScienceandTechnologyofChinaHefe230026China SchoolofMechanicalandAutomotiveEngineering HefeiPolytechnicUniversityHefei230069China DepartmentofManagementScience UniversityofScienceandTechnologyofChinaHefei230026.China

As a result of the fierceness of business competition, companies, to remaincompetitive, have to charm their customers by anticipating their needs and being able to rapidlydevelop exciting new products for them. To overcome this challenge, technology forecasting isconsidered as a powerful tool in today's business environment, while there are as many successstories as there are failures, a good application of this method will give a good result. Amethodology of integration of patterns or lines of technology evolution in TRIZ parlance ispresented, which is also known as TRIZ technology forecasting, as input to the QFD process to designa new product. For this purpose, TRIZ technology forecasting, one of the TRIZ major tools, isdiscussed and some benefits compared to the traditional forecasting techniques are highlighted. Thena methodology to integrate TRIZ technology forecasting and QFD process is highlighted.

关键词： Theory of inventive problem solving (TRIZ) Quality function deployment(QFD) Technology forecasting Patterns/lines of technology evolution

An analysis on spatial variation of urban human thermal comfort in Hangzhou, China

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2004年第2期16卷 332-338页

作者： wangwei-wu ZHULi-zhong WANGRen-chao CollegeofEnvironmentalandResourceSciences ZhejiangUniversityHangzhou310029China.

Urban human thermal comfort(UHTC) is affected for interacting of weather condition and underlying surface framework of urban area. Urban underlying surface temperature value and Normalized Difference Vegetation Index(NDVI) were calculated using image interpreting and supervised classification technique by ERDAS IMAGE software using 1991 and 1999 Landsat TM images data. Reference to the relational standard of assessing human thermal comfort and other meteorology data of Hangzhou City in summer, air temperature and relative humidity variation of different land types of underlying surface were inversed. By choosing discomfort index as an indictor, the spatial distribution characteristic and the spatial variation degree of UHTC were estimated and mapped on a middle scale, that is, in six districts of Hangzhou. The main characteristics of UHTC spatial variation from 1991 to 1999 were revealed using a GIS-based calculation model. The variation mechanism were analyzed and discussed from the viewpoint of city planning, construction and environmental protection.

关键词： urban human thermal comfort(UHTC) remote sen sing(RS) geographic information system(GIS) spatial distribution variation me chanism

Streamwater chemistry and flow dynamics along vegetation-soil gradient in a subalpine Abies fabri forest watershed, China

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2004年第5期16卷 722-729页

作者： SHANBao-qing wangwei-dong YINCheng-qing SKLEAC ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China

Streamwater chemistry and spatial flow dynamics from a subalpine Abies fabri forest in an experimental watershed located in the east slope of Gongga Mountain were analyzed to gain insights into the gradient effect of primary community succession on the stream biogeochemical process. Results showed that high sand content(exceeding 80%) and porosity in the soil(exceeding 20% in A horizon and 35% in B horizon), as well as a thick humus layer on the soil surface, made the water exchange quickly in the Huangbengliu(HBL) watershed. Consequently, no surface runoff was observed, and the stream discharge changed rapidly with the daily precipitation. The flow trends of base ions in the stream water were influenced by the Abies fabri succession gradient. Ca 2+ , HCO - 3 and SO 2- 4 were the dominant anions in the streamwater in this region. A significant difference of Ca 2+ , HCO - 3 and SO 2- 4 concentration exported between the succession stages in the watershed can be found. But they had the similar temporal change in the stream flow. Ca 2+ , HCO - 3 and SO 2- 4 showed significantly negative correlations with the daily precipitation and the stream discharge. \;Concentrations of Cl -, Na +, K +, and Mg 2+ were low in all streamwaters monitored and we observed no differences along the Abies fabri succession gradient. Low ratios of Na:(Na+Ca) (range from 0.1 to 0.2) implied cations were from bedrock weathering(internal source process in the soil system) in this region. But, a variance analysis showed there were almost no differences between rainwater and streamwaters for Mg 2+ , Na +, K +, and Cl - concentrations. This indicated that they might be come from rainfall inputs(external source). The highly mobile capacity, rapid water exchange between precipitation and discharge, and long-term export lead to this observed pattern were suggested.

关键词： water chemistry succession subalpine coniferous forest Abies fabri watershed Gongga Mt.

侦查阶段涉案企业合规改革的实践困境与路径研究

在线全文

学校读者我要写书评

暂无评论

皖西学院学报 2024年第3期40卷 63-68页

作者：王也姚纯丽崔汪卫安徽警官职业学院警察系安徽合肥230031 安徽大学法学院安徽合肥230601 安庆师范大学法学院安徽安庆246133

涉案企业合规改革前移至侦查阶段对营造法治化营商环境,促使企业合规经营具有一定意义。然而,实践中面临侦查阶段的合规工作基本模式不明、合规工作与“挂案”清理工作缺乏结合基础、权力运行缺乏有效制约等问题。为推动侦查阶段的企业... 详细信息

涉案企业合规改革前移至侦查阶段对营造法治化营商环境,促使企业合规经营具有一定意义。然而,实践中面临侦查阶段的合规工作基本模式不明、合规工作与“挂案”清理工作缺乏结合基础、权力运行缺乏有效制约等问题。为推动侦查阶段的企业合规改革顺利开展,应明确以侦查机关主导合规工作模式为主,检察机关主导合规工作模式为补充的合规启动模式,构建合规工作与检察建议相结合的工作方式,并建立监察机关为主体的合规工作监察体系。

关键词：企业合规侦查阶段合规工作模式合规检察建议合规监察

在线全文

学校读者我要写书评

暂无评论

教师个人实践理论的内涵、特征与建构策略

当代教育理论与实践 2024年第1期16卷 147-156页

作者：李王伟潘正茂江苏师范大学智慧教育学院江苏徐州221116 佛山市三水区西南街道第四中学广东佛山528119

教育家型教师培养是新时代基础教育高质量发展的重要推动力。作为其重要实践标志的教师个人实践理论近来也受到教育研究者和一线教师的广泛关注。从个人实践理论的意义探讨出发,阐明中小学教师个人实践理论的内涵及特征,提炼出基于专业... 详细信息

教育家型教师培养是新时代基础教育高质量发展的重要推动力。作为其重要实践标志的教师个人实践理论近来也受到教育研究者和一线教师的广泛关注。从个人实践理论的意义探讨出发,阐明中小学教师个人实践理论的内涵及特征,提炼出基于专业探究的教师个人实践理论建构策略及规律,以促成教师个人实践理论的建构,为教育家型教师培养提供理论和实践参考。

关键词：个人实践理论建构策略凝练案例研究