生物陶瓷内部成孔与贯通方式的研究

多孔羟基磷灰石（HA）陶瓷内部结构满足细胞向内部渗透、迁移、粘附和生长的条件。实验探讨了HA陶瓷内部成孔与孔道连结的机理与技术，采用添加制孔剂和固化纤维2种方法制备系列样品，测算了样品气孔率，并对微观结构进行扫描电镜观察，最终确定可人工调控内部结构的HA陶瓷成孔与贯通技术。     

Web‐Like Interconnected Carbon Networks from NaCl‐Assisted Pyrolysis of ZIF‐8 for Highly Efficient Oxygen Reduction Catalysis

The oxygen reduction reaction (ORR) is under intense research due to its significance in energy storage and conversion processes. Recent studies show that interconnected and hierarchically porous structures can further enhance ORR kinetics as well as catalyst durability, but their preparation can be quite time and/or chemical consuming. Here, a simple approach is reported to prepare such complex structures by pyrolyzing composites containing NaCl and ZIF‐8. The templating effect of molten NaCl connects ZIF‐8 particles into web‐like carbon networks. During ORR activity measurements, it achieves a 0.964 V onset potential and a 38 mV dec^?1 Tafel slope, which are comparable to those of the benchmark Pt/C (0.979 V and 40 mV dec^?1). Due to the metal‐free feature, this catalyst exhibits a 16 mV shift in half‐wave potential after a 10 000‐cycle durability test, which is only 60% of that of Pt/C. The catalyst is also tested in Zn–air batteries and the assemblies are able to work at above 1.2 V for 140 h, which triples the life held by those with Pt/C. This study demonstrates a facile strategy to prepare metal‐free ORR catalysts with interconnectivity and hierarchical porosity, and proves their great potentials in ORR catalysis and Zn–air batteries.     

基于概念主干H的知识联通及其联通测度

1 引言领域专业知识在决策系统、智能教学系统(ITS)、知识查询系统等高技术产品中具有重要的作用。知识库是机器智能的重要来源,而大量实践证明计算机真正具有智能不仅需要大型知识库,而且更需要知识间广泛的互连。     

多域光网络互联互通技术

首先介绍了光网络设备的发展状况,然后分析了现有光网络域间互联互通中的主要问题,接着介绍了现有的几种关于多域光网络域间互联互通的技术,包括静态互联技术、GNMS技术、E-NNI技术、PCE技术和SDON技术.通过分析各种技术的优缺点,介绍了两种技术结合使用的方案.     

构建高贯通多孔生物陶瓷的纤维处理与功效

采用质量分数为1％乙酸和质量分数为2％聚合物配置的CSMMG胶液，涂层在棉纤维上，以作为陶瓷体内隧道的支撑体，织入质量分数为8％的聚乙烯醇作粘结荆和质量分数为40％的羟基磷灰石粉混合制备陶瓷料浆中形成初坯，进行烧结．扫描电镜观察表明，样品内隧道定向连通，分布均匀，成型完整，内壁呈细条纹，满足组织细胞生长、迁移、黏附的条件；X射线衍射分析验证样品未引入异质成分．     

A Hierarchical Model of Supply-Chain Integration: Information Sharing and Operational Interdependence in the US Grocery Channel

This paper examines costs of and motivations for interconnectivity within the grocery supply chain, employing evidence from multiple case studies and survey data to develop a seven-level model of technology-enabled supply-chain connectivity and channel interdependence. This theoretical model, built around a modified transactions-costs framework, is illustrated using examples of processes that span multiple levels of interconnectivity and interdependence within the grocery channel between different groups of customers and suppliers. Our analysis suggests that while a discernible hierarchy of levels of IT-enabled interorganizational connectivity exists, not all relationships necessarily evolve to the highest level of virtual integration. Indeed, limits on executive attention preclude this level from being achieved by more than a small fraction of trading partners. The model generates eight testable hypotheses for further study.     

蜡球造孔法制备多孔HA陶瓷支架及其性能优化

组织工程支架的贯通性对其体内生物学表现具有重要影响。采用甲壳素溶胶体系和蜡球造孔剂制备多孔羟基磷灰石(HA)陶瓷支架, 考查在相同模压条件下, 不同浆料/造孔剂比例对多孔HA陶瓷支架的孔隙率、收缩率、贯通性、多孔结构以及抗压强度的影响。结果表明: 该方法可以制备具有高孔隙的多孔HA陶瓷支架, 随着造孔剂比例的增大, 支架的贯通性更好, 当浆料/造孔剂比例为1:1.2时可以得到孔隙率、贯通性、力学性能最优的多孔HA陶瓷支架。     

Chameleon聚类算法的Weka实现

为了克服Weka系统在聚类算法方面的不足,在Weka的开源环境下进行了二次开发,扩充了聚类算法。介绍了Chameleon算法的基本原理和构建步骤,给出算法的具体描述,并将Chameleon算法嵌入Weka平台,充分利用了其中的类和可视化功能。对实现的系统进行了实验和测试,并对嵌入的算法和原有聚类算法k—means进行了对比分析。实验结果表明,Chameleon算法可获得更好的聚类效果。