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   75篇
  免费   0篇
  国内免费   1篇
化学工业   20篇
机械仪表   1篇
矿业工程   1篇
能源动力   1篇
轻工业   8篇
无线电   7篇
一般工业技术   22篇
冶金工业   3篇
自动化技术   13篇
  2024年   2篇
  2023年   2篇
  2022年   3篇
  2021年   2篇
  2019年   4篇
  2018年   7篇
  2017年   2篇
  2016年   3篇
  2014年   4篇
  2013年   8篇
  2012年   5篇
  2011年   9篇
  2010年   4篇
  2009年   5篇
  2008年   2篇
  2007年   4篇
  2006年   1篇
  2005年   4篇
  2004年   1篇
  1998年   1篇
  1997年   1篇
  1979年   1篇
  1975年   1篇
排序方式: 共有76条查询结果,搜索用时 0 毫秒
51.
52.
    
Rechargeable Mg-ion Batteries (RMB) containing a Mg metal anode offer the promise of higher specific volumetric capacity, energy density, safety, and economic viability than lithium-ion battery technology, but their realization is challenging. The limited availability of suitable inorganic cathodes compatible with electrolytes relevant to Mg metal anode restricts the development of RMBs. Despite the promising capability of some oxides to reversibly intercalate Mg+2 ions at high potential, its lack of stability in chloride-containing ethereal electrolytes, relevant to Mg metal anode hinders the realization of a full practical RMB. Here the successful in situ encapsulation of monodispersed spherical V2O5 (≈200 nm) is demonstrated by a thin layer of VS2 (≈12 nm) through a facile surface reduction route. The VS2 layer protects the surface of V2O5 particles in RMB electrolyte solution (MgCl2 + MgTFSI in DME). Both V2O5 and V2O5@VS2 particles demonstrate high initial discharge capacity. However, only the V2O5@VS2 material demonstrates superior rate performance, Coulombic efficiency (100%), and stability (138 mA h g−1 discharge capacity after 100 cycles), signifying the ability of the thin VS2 layer to protect the V2O5 cathode and facilitate the Mg+2 ion intercalation/deintercalation into V2O5.  相似文献   
53.
    
Over the past few decades, vitamin D deficiency has been recognized as a serious global public health challenge. The World Health Organization has recommended fortification of foods with vitamin D, but this is often challenging because of its low water solubility, poor chemical stability, and low bioavailability. Studies have shown that these challenges can be overcome by encapsulating vitamin D within well-designed delivery systems containing nanoscale or microscale particles. The characteristics of these particles, such as their composition, size, structure, interfacial properties, and charge, can be controlled to attain desired functionality for specific applications. Recently, there has been great interest in the design, production, and application of vitamin-D loaded delivery systems. Many of the delivery systems reported in the literature are unsuitable for widespread application due to the complexity and high costs of the processing operations required to fabricate them, or because they are incompatible with food matrices. In this article, the concept of “fortification by design” is introduced, which involves a systematic approach to the design, production, and testing of colloidal delivery systems for the encapsulation and fortification of oil-soluble vitamins, using vitamin D as a model. Initially, the challenges associated with the incorporation of vitamin D into foods and beverages are reviewed. The fortification by design concept is then described, which involves several steps: (i) selection of appropriate vitamin D form; (ii) selection of appropriate food matrix; (iii) identification of appropriate delivery system; (iv) identification of appropriate production method; (vii) establishment of appropriate testing procedures; and (viii) system optimization.  相似文献   
54.
    
The challenge of bacterial infection increases the risk of mortality and morbidity in acute and chronic wound healing. Silver nanoparticles (Ag NPs) are a promising new version of conventional antibacterial nanosystem to fight against the bacterial resistance in concern of the drug discovery void. However, there are several challenges in controlling the size and colloidal stability of Ag NPs, which readily aggregate or coalesce in both solid and aqueous state. In this study, a template‐guided synthesis of ultrafine Ag NPs of around 2 nm using water‐soluble and biocompatible γ‐cyclodextrin metal‐organic frameworks (CD‐MOFs) is reported. The CD‐MOF based synthetic strategy integrates AgNO3 reduction and Ag NPs immobilization in one pot achieving dual functions of reduced particle size and enhanced stability. Meanwhile, the synthesized Ag NPs are easily dispersible in aqueous media and exhibit effective bacterial inhibition. The surface modification of cross‐linked CD‐MOF particles with GRGDS peptide boosts the hemostatic effect that further enhances wound healing in synergy with the antibacterial effect. Hence, the strategy of ultrafine Ag NPs synthesis and immobilization in CD‐MOFs together with GRGDS modification holds promising potential for the rational design of effective wound healing devices.  相似文献   
55.
56.
Neural Computing and Applications - The hydraulic capacity of a channel is impacted due to sediment deposition in urban drainage and sewer system. As a result, the self-cleansing mechanism is a...  相似文献   
57.
    
Drought is the degradation of land in arid, semi-arid and dry sub-humid regions caused primarily by human activity and climatic variations. The present study is the first attempt to identify and monitor drought using a vegetation index, a vegetation-water index and land surface temperature (LST) data for Nepal and central northeastern India. We propose a Vegetation Water Temperature Condition Index (VWTCI) for monitoring drought on a regional scale. The VWTCI includes the Normalized Difference Water Index (NDWI), which measures the water status in vegetation, the Normalized Difference Vegetation Index (NDVI) and LST data. To validate the approach, the VWTCI was compared with the Vegetation Temperature Condition Index (VTCI) and Tropical Rainfall Measuring Mission (TRMM) 3B31 Precipitation Radar (PR) data. The study revealed a gradual increase in the extent of drought in the central part of the study area from 2000 to 2004. Certain constant drought areas were also identified and the results indicate that these areas are spreading slowly towards the northeast into the central part of the study area. Comparison of the drought areas also shows a decrease in rainfall in June and July from 2000 to 2004.  相似文献   
58.
    
Concentrated growth factor (CGF) is 100% blood-derived, cross-linked fibrin glue with platelets and growth factors. Human CGF clot is transformed into membrane by a compression device, which has been widely used clinically. However, the mechanical properties of the CGF membranes have not been well characterized. The aims of this study were to measure the tensile strength of human CGF membrane and observe its behavior as a scaffold of BMP-2 in ectopic site over the skull. The tensile test of the full length was performed at the speed of 2mm/min. The CGF membrane (5 × 5 × 2 mm3) or the CGF/BMP-2 (1.0 μg) membrane was grafted onto the skull periosteum of nude mice (5-week-old, male), and harvested at 14 days after the graft. The appearance and size of the CGF membranes were almost same for 7 days by soaking at 4 °C in saline. The average values of the tensile strength at 0 day and 7 days were 0.24 MPa and 0.26 MPa, respectively. No significant differences of both the tensile strength and the elastic modulus were found among 0, 1, 3, and 7 days. Supra-periosteal bone induction was found at 14 days in the CGF/BMP-2, while the CGF alone did not induce bone. These results demonstrated that human CGF membrane could become a short-term, sticky fibrin scaffold for BMP-2, and might be preserved as auto-membranes for wound protection after the surgery.  相似文献   
59.
60.
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