星状金纳米晶的制备及应用研究进展

主要介绍了新型星状金纳米晶的研究进展,介绍了其主要的制备工艺,阐述了星状金纳米晶在药物运载与释放、催化、及SERS增强方面的显著应用;同时简略介绍了一些其他贵金属星状纳米晶的应用性能.制备中通过添加不同贵金属晶种、还原剂与表面活性剂,控制[金属盐溶液浓度]/[晶种数目]的摩尔比,调节星状纳米晶尖端长度与数目;同时对不同贵金属星状纳米晶的应用前景进行了展望.     

中外人居环境理论与实践发展述评

本文试图全面回顾、介绍西方学者关于城市人居环境研究的代表性观点,归纳总结国内学者在这一领域的研究与实践,并提出近今研究中值得注意的问题.     

多扇图的Pebbling数和Graham猜想

图G的pebbling数f(G)是最小的整数n,使得不论n个pebble如何放置在G的顶点上,总可以通过一系列的pebbling移动把1个pebble移到任意一个顶点上,其中一个pebbling移动是从一个顶点处移走两个pebble而把其中的一个移到与其相邻的一个顶点上。Graham猜想对于任意的连通图G和H有f(G×H)f(G)f(H)。多扇图F_n1,n2,…,nm是指阶为n₁+n₂+…+n_m+1的联图P₁∨(P_n1∪P_n2∪…∪P_nm)。本文首先给出了多扇图的pebbling数,然后证明了多扇图F_n1,n2,…,nm具有2-pebbling性质,最后论述了对于一个多扇图和一个具有2-pebbling性质的图的乘积来说,Graham猜想是成立的。作为一个推论,当G和H都是多扇图时,Graham猜想成立。     

Separation of systems based on uranium hexafluoride and some of halogen fluorides

The purpose of this paper is to present the results of the comprehensive study of the phase equilibriums liquid-solid and liquid-vapour in binary and ternary systems, formed by uranium hexafluoride, bromine trifluoride and iodine pentafluoride.Investigation of the phase equilibriums in condensed systems is done by methods of differential thermoanalysis and visual polythermal analysis. All systems belong to simple eutectics; formation of the compounds is not detected. For all systems under investigation diagrams of the phase equilibrium liquid-solid are plotted.Phase equilibriums liquid-vapour in studied systems were studied by statistical method. All systems are non-aseotropic. The article presents diagrams of the phase equilibrium liquid-vapour in binary systems, pressure of the saturated vapour dependences on liquid composition, surface of the boiling liquid and lines of the constant content of uranium hexafluoride and iodine pentafluoride in vapour phase of the ternary system UF₆-BrF₃-IF₅.     

Issues in the use of ratings-based versus choice-based conjoint analysis in operations management research

Conjoint analysis has played an important role in helping make a number of operations management decisions including product and service design, supplier selection, and service operations capacity. Many recent advances in this area have raised questions about the most appropriate form of conjoint analysis for this research. We review recent developments in the literature and provide new evidence on how the choice between ratings- and choice-based conjoint models might affect the estimates of customer demand used in operations management models.     

自反Banach空间中的约束凸向量优化问题的弱有效解集的非空有界性的刻画

本文首先研究无限维自反Banach空间中的锥约束凸向量优化问题的弱有效解集的非空有界性的各种刻画.然后将获得的结果用于研究一类罚函数方法的收敛性.     

SARs of the antiprotozoal action of 6,7-diaryl-bicyclo[2.2.2]octan-2-ols

Abstract  Several 4-amino-6,7-diarylbicyclo[2.2.2]octan-2-ols bearing varying substituents on the aromatic rings were synthesized following a manual method for applying the Hansch approach. All new compounds were tested for their activity against the causative organisms of East African sleeping sickness and malaria tropica. Structure activity relationships are discussed. Graphical abstract        

CVD法制备高质量金刚石单晶研究进展

本文介绍了制备单晶金刚石的主要方法并对其进行了对比,从籽晶选择、预处理和生长工艺几个方面综述了微波等离子体化学气相沉积法制备金刚石单晶的研究进展,并简单介绍了目前国内外在单晶金刚石制备上的进展,最后对CVD金刚石单晶在电子领域的应用进行了展望.     

干旱区区域土壤盐渍化监测研究进展及其未来热点

土壤盐渍化是干旱区农业生产的重要障碍,威胁着绿洲生态环境的稳定。监测土壤盐渍化动态,掌握盐渍化土壤的分布规律,探索盐渍化的发生发展机理,总结土壤盐渍化的研究方法,对干旱区农业生产活动和生态安全稳定具有重要意义。盐渍化的发展变化不仅受到自然环境的强烈作用,同时也受到人类活动的深刻影响。随着人类活动的加剧,盐渍化问题日益突出,因此本文在中外关于土壤盐渍化研究的基础上,系统总结了我国干旱区区域土壤盐渍化监测的主要方法,为土壤盐渍化监测、预报和调控的方法与理论提供了补充,同时也提出了当前干旱区区域土壤盐渍化监测研究存在的问题,以及强调了今后面向区域农业生产迫切需要开展的四个领域的研究,为确保土地利用的可持续性,构建和谐的人地关系提供了决策参考。     

Synthesis,Structure and Theoretical Research of a New Triaryl Phosphine Complex [HgCl<Subscript>2</Subscript>(PPh<Subscript>2</Subscript>Bz)<Subscript>2</Subscript>] (PPh<Subscript>2</Subscript>Bz = Benzyldiphenylphosphine)

Abstract  The solution-phase reaction of HgCl₂ with benzyldiphenylphosphine (PPh₂Bz) yields a new triaryl phosphine complex [HgCl₂(PPh₂Bz)₂] (1) with the bigger P–Hg–P angle, the longer Hg–Cl bond, and the shorter Hg–P bond. Comparison of the sensitive bond parameters with similar compounds and the theoretical calculation show that the σ-donating abilities of tertiaryl phosphine ligands toward HgCl₂ conforms to the following order: PEt₃ > PPh₂Bz > P(2-thienyl)₃ > dppf > PPh₃. Graphical Abstract  The solution-phase reaction of HgCl₂ with benzyldiphenylphosphine (PPh₂Bz) yields a new triaryl phosphine complex [HgCl₂(PPh₂Bz)₂] (1) with the bigger P–Hg–P angle. Comparison of the sensitive bond parameters with similar compounds shows that the σ-donating abilities of tertiaryl phosphine ligands toward HgCl₂ conforms to the following order: PEt₃ > PPh₂Bz > P(2-thienyl)₃ > dppf > PPh₃.