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21.
以提升LED产业集群中资源组织效率为目的,基于产业链创新服务平台视角,从产业链平台的业务流程出发,寻找资源组织的关键路径。基于提升资源组织速度的考虑,使用包括基本信息层、结构信息层、活动信息层、能力信息层和时间信息层的5层资源描述方法构建LED产业平台中虚拟单元。通过LED产业链平台中的应用,证明本方法在实践中是有效的。  相似文献   
22.
走出书斋——浅论移动阅读   总被引:4,自引:0,他引:4  
张晓红  李卓 《现代情报》2007,27(2):188-190
移动阅读是目前新出现的一种阅读方式,这种阅读方式产生的背景是什么,以及对中国而言,移动阅读的普及存在的困难和障碍是什么,本文围绕这两点展开了深入探讨。  相似文献   
23.
The objectives of this study were to assess the potential of two photosynthetic bacteria (PSB), Rhodopseudomonas palustris HZ0301 and Rhodobacter sphaeroides HZ0302, as probiotics in aquaculture. The viability of HZ0301 and HZ0302 in simulated gastric transit conditions (pH 2.0, pH 3.0 and pH 4.0 gastric juices) and in simulated small intestinal transit conditions (pH 8.0, with or without 0.3% bile salts) was tested. The effects of HZ0301 and HZ0302 on the viability and permeability of intestinal epithelial cell in primary culture of tilapias, Oreochrornis nilotica, were also detected. All the treatments were deter- mined with three replicates. The simulated gastric transit tolerance of HZ0301 and HZ0302 strains was pH-dependent and correspondingly showed lower viability at pH 2.0 after 180 min compared with pH 3.0 and pH 4.0. Both HZ0301 and HZ0302 were tolerant to simulated small intestine transit with or without bile salts in our research. Moreover, there was no significant difference (P〉0.05) among three treatments including the control and the groups treated with HZ0301 or HZ0302 both in intestinal epithelial cell viability and membrane permeability, showing no cell damage. In summary, this study demonstrated that HZ0301 and HZ0302 had high capacity of upper gastrointestinal transit tolerance and were relatively safe for intestinal epithelial cells of tilapias.  相似文献   
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为了进一步培养民族高校学生的实验技能,在细胞生物学实验课程教学中,实验课教学小组通过不断改革教学方法,适应新的教学体系,及时调整实验教学内容和形式,以及建立完善的成绩评定体系,把好教学质量关,充分发掘学生的潜能,增强学生学习的自信心和兴趣,从而达到提高学生实验技能的目的.通过对近4年的细胞生物学实验成绩的分析,结果显示,实验对绝大多数学生在提高专业技能、培养独立工作能力、提高分析问题和解决问题能力、提高自主学习意识和能力、增强团队协作意识等方面有很大帮助.  相似文献   
26.
待复垦土地的适宜性评价是制定土地复垦方案的前提和基础;以淮南潘北煤矿为例,结合矿区地形实际情况并参考评价单元的划分依据,将该矿区的复垦土地的适宜性评价单元划分为塌陷水域、中度破坏耕地、轻度破坏耕地、中度破坏林地、轻度破坏林地、搬迁旧村址6个评价单元,筛选出了该矿待复垦土地评价因子并确定出该矿区待复垦土地的复垦方向,为土地科学利用提供建议。  相似文献   
27.
本文讨论了平面波法在光子晶体光纤中的应用,在光子晶体光纤的横截面内选取包含芯层的一个大晶格,形成一个假想的二维周期结构,用平面波将模式磁场展开.就可以求解任意横截面光纤中的麦克斯韦方程。  相似文献   
28.
基于带内自回传小基站系统,提出一种以用户为中心动态成簇的部分协作干扰抑制方案。根据带内自回传小基站复用接入与回传无线资源的特点,形成以最大化系统下行接入链路吞吐量为目标,联合回传链路资源分配与接入链路预编码设计的优化问题。由于所提问题难以获得最优解,基于凸松弛和分块坐标下降方法,提出一种次优的迭代求解算法。仿真结果表明所提算法能根据回传速率调整协作簇的大小,均衡小基站回传负载,提升系统接入链路的吞吐量。  相似文献   
29.
Cartilage injuries are often devastating and most cannot be cured because of the intrinsically low regenerative capacity of cartilage tissues. Although stem-cell therapy has shown enormous potential for cartilage repair, the therapeutic outcome has been restricted by low survival rates and poor chondrocyte differentiation in vivo. Here, we report an injectable hybrid inorganic (IHI) nanoscaffold that facilitates fast assembly, enhances survival and regulates chondrogenic differentiation of stem cells. IHI nanoscaffolds that strongly bind to extracellular matrix (ECM) proteins assemble stem cells through synergistic 3D cellcell and cell–matrix interactions, creating a favorable physical microenvironment for stem-cell survival and differentiation in vitro and in vivo. Additionally, chondrogenic factors can be loaded into nanoscaffolds with a high capacity, which allows deep, homogenous drug delivery into assembled 3D stem-cell-derived tissues for effective control over the soluble microenvironment of stem cells. The developed IHI nanoscaffolds that assemble with stem cells are injectable. They also scavenge reactive oxygen species and timely biodegrade for proper integration into injured cartilage tissues. Implantation of stem-cell-assembled IHI nanoscaffolds into injured cartilage results in accelerated tissue regeneration and functional recovery. By establishing our IHI nanoscaffold-templated 3D stem-cell assembly method, we provide a promising approach to better overcoming the inhibitory microenvironment associated with cartilage injuries and to advance current stem-cell-based tissue engineering.  相似文献   
30.
Developing photovoltaic materials with simple chemical structures and easy synthesis still remains a major challenge in the industrialization process of organic solar cells (OSCs). Herein, an ester substituted poly(thiophene vinylene) derivative, PTVT-T, was designed and synthesized in very few steps by adopting commercially available raw materials. The ester groups on the thiophene units enable PTVT-T to have a planar and stable conformation. Moreover, PTVT-T presents a wide absorption band and strong aggregation effect in solution, which are the key characteristics needed to realize high performance in non-fullerene-acceptor (NFA)-based OSCs. We then prepared OSCs by blending PTVT-T with three representative fullerene- and NF-based acceptors, PC71BM, IT-4F and BTP-eC9. It was found that PTVT-T can work well with all the acceptors, showing great potential to match new emerging NFAs. Particularly, a remarkable power conversion efficiency of 16.20% is achieved in a PTVT-T:BTP-eC9-based device, which is the highest value among the counterparts based on PTV derivatives. This work demonstrates that PTVT-T shows great potential for the future commercialization of OSCs.  相似文献   
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