首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   78篇
  免费   9篇
  国内免费   3篇
电工技术   4篇
综合类   5篇
化学工业   10篇
机械仪表   3篇
建筑科学   11篇
能源动力   7篇
轻工业   6篇
石油天然气   2篇
无线电   14篇
一般工业技术   11篇
冶金工业   2篇
原子能技术   2篇
自动化技术   13篇
  2024年   1篇
  2022年   2篇
  2021年   5篇
  2020年   4篇
  2018年   5篇
  2016年   2篇
  2015年   2篇
  2014年   4篇
  2013年   3篇
  2012年   6篇
  2011年   12篇
  2010年   7篇
  2009年   6篇
  2008年   8篇
  2007年   3篇
  2006年   5篇
  2005年   5篇
  2004年   3篇
  2002年   2篇
  2001年   3篇
  2000年   1篇
  1998年   1篇
排序方式: 共有90条查询结果,搜索用时 31 毫秒
1.
Vacuum insulation panels (VIPs) have a thermal resistance that is about a factor of 10 higher than that of equally thick conventional polystyrene boards. VIPs nowadays mostly consist of a load-bearing kernel of fumed silica. The kernel is evacuated to below 1 mbar and sealed in a high- barrier laminate, which consists of several layers of Al-coated polyethylene (PE) or polyethylene terephthalate (PET). The laminate is optimized for extremely low leakage rates for air and moisture and thus for a long service life, which is required especially for building applications. The evacuated kernel has a thermal conductivity of about 4 × 10−3 W · m−1 · K−1 at room temperature, which results mainly from solid thermal conduction along the tenuous silica backbone. A U-value of 0.2 W · m−2 · K−1 results from a thickness of 2 cm. Thus slim, yet highly insulating fa?ade constructions can be realized. As the kernel has nano-size pores, the gaseous thermal conductivity becomes noticeable only for pressures above 10 mbar. Only above 100 mbar the thermal conductivity doubles to about 8 × 10−3 W · m−1 · K−1, such a pressure could occur after several decades of usage in a middle European climate. These investigations revealed that the pressure increase is due to water vapor permeating the laminate itself, and to N2 and O2, which tend to penetrate the VIP via the sealed edges. An extremely important innovation is the integration of a thermo-sensor into the VIP to nondestructively measure the thermal performance in situ. A successful “self-trial” was the integration of about 100 hand-made VIPs into the new ZAE-building in Würzburg. Afterwards, several other buildings were super-insulated using VIPs within a large joint R&D project initiated and coordinated by ZAE Bayern and funded by the Bavarian Ministry of Economics in Munich. These VIPs were manufactured commercially and integrated into floorings, the gable fa?ade of an old building under protection, the roof and the facades of a terraced house as well as into an ultra-low-energy “passive house” and the slim balustrade of a hospital. The thermal reliability of these constructions was monitored using an infrared camera.Invited paper presented at the Seventh European Conference on Thermophysical Properties, September 5-8, 2005, Bratislava, Slovak Republic.  相似文献   
2.
本文研究了进口 VIP 板在某直冷冰箱冷冻室部位6种不同方案的应用效果,结果表明,产品能耗随 VIP 板厚度、数量 (或覆盖面积)的增加而降低,耗电量最多可降低15%,冷冻负载温度回升时间可延长27%,压缩机工作系数减少22%。我们认为,优化冰箱制冷系统有利于提高 VIP 冰箱的性能,但是在 VIP 板的应用方面也应考虑到成本与能耗的关系。  相似文献   
3.
This study investigated the possibility of using near-infrared spectroscopy (NIRS) for the authentication of Asiago d’allevo, a protected designation of origin cheese from northern Italy. Latent variable models applied on spectral data were developed and used to estimate several chemical properties and to classify the available dataset according to the location and management of the cheesemaking factory (lowland and alpine), the ripening age (6, 12, 18 and 36 months), the altitude of milk production (low, medium, medium–high and high), and the period of the year of the cheese production (May, July and September). The variable importance in projection index was used to identify the most informative spectral regions for discrimination. Results showed that NIR spectra can be used both to accurately estimate several chemical properties and to classify the samples according to the different experimental conditions under investigation with the same discrimination capacity provided by traditional chemical analysis.  相似文献   
4.
Demand for energy efficient buildings has increased drastically in recent years and this trend will continue in the future. Insulating building elements will play a key role in meeting this demand by reducing heat losses through the building fabric. Due to their higher thermal resistance, Vacuum Insulation Panels (VIPs) would be a more energy efficient alternative to conventional building insulation materials. Thus, efforts to develop VIPs with characteristics suitable for applications to new and existing buildings are underway. This paper provides a review of important contemporary developments towards producing VIPs using various materials such as glass fibre, foams, perlite and fibre/powder composites. The limitations of the materials currently used to fabricate VIPs have not been emphasised in detail in previous review papers published. Selection criteria, methods to measure important properties of VIPs and analytical and numerical models presented in the past have been detailed. Limitations of currently employed design tools along with potential future materials such as Nano/microcellular foams and SiOx/SiNx coatings for use in VIPs are also described.  相似文献   
5.
VIP生活楼是上海世博会世博村内最高标准的超五星级酒店。酒店设计尊重世博村的总体规划;充分结合保护原建筑为酒店餐厅与高级会所;利用保留绿地提升酒店环境品质。为使每间客房观赏到的黄浦江景最大化,酒店采用了折板式形体,达到了区域地标的效果。酒店合理的交通组织、功能布局和立面造型也成为几大设计特色。  相似文献   
6.
7.
真空导入工艺用不饱和聚酯树脂的研制   总被引:3,自引:1,他引:2  
本文研究合成的不饱和聚酯树脂具有较低的粘度和较好的固化特性,粘度控制在0.21Pa.s左右,非常适用于真空导入工艺,该树脂采用真空导入工艺成型的玻璃钢制品各项性能都非常优越,有些性能指标几乎是通用树脂手糊成型性能的两倍左右。  相似文献   
8.
MSTP技术在大客户专线接入中的应用   总被引:2,自引:0,他引:2  
对大客户专线接入的种类、业务流向、实现技术等进行分析,结合MSTP技术的特点及主要技术优势提出合适的应用范围,并对MSTP的实际组网应用进行了举例。  相似文献   
9.
真空绝热板(VIP)技术及其发展   总被引:7,自引:0,他引:7  
针对真空绝热板技术的结构设计、绝热机理、核心技术及影响真空绝热板寿命的关键因素等内容进行了详尽的分析与探讨,介绍了国外VIP技术发展的前沿动向并结合国内真空绝热板技术的发展历程及当前发展水平进行了讨论,对国内VIP技术未来发展方向提出了几点认识和建议。  相似文献   
10.
针对传统SATA控制器存储系统性能受限、安全性不足问题,提出并设计了一款可实现PCIe(peripheral component interconnect express)与SATA(serial advanced technology attachment)协议传输数据互转,基于SM4算法实现本地数据安全存储的高速安全存储SoC(system of chip)芯片。通过构建合理的片内PCIe与SATA互转数据传输通路,利用PCIe VIP(verification intellectual property)及UVM(universal verification methodology)技术搭建系统应用级仿真验证平台,设计基于SystemVerilog语言的源激励用例和C固件,利用脚本自动化控制实现仿真验证。仿真结果表明,该SoC芯片通路上各设备链路建立正确,实现PCIe与SATA互转通路数据正确传输,测试带宽472 MBps,基于SM4算法的本地安全存储加解密无误,SM4算法加解密带宽1.33 Gbps。根据仿真实验结果可知,该PCIe与SATA桥接转换SoC芯片架构设计是可行的,实现了本地数据的安全存储,为进一步进行数据高速转换访问、安全传输存储研究奠定了重要基础。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号