CLIFFORD MARTINGALES Φ-EQUIVALENCE BETWEEN S（f） AND f^＊

ＣＬＩＦＦＯＲＤＭＡＲＴＩＮＧＡＬＥＳΦ－ＥＱＵＩＶＡＬＥＮＣＥＢＥＴＷＥＥＮＳ（ｆ）ＡＮＤｆ￥ＬＯＮＧＲＵＬＩＮ；ＱＩＡＮＴＡＯ（ＩｎｓｔｉｔｕｔｅｏｆＭａｔｈｅｍａｔｉｃｓ，ＡｃａｄｅｍｉａＳｉｎｉｃａ，Ｂｅｉｊｉｎｇ１０００８０，Ｃｈｉｎａ．）...     

提升教学魅力,打造一门好课——《材料表面与界面》教学改革探索

《材料表面与界面》为高分子材料与工程专业复合材料方向的限选课。本课程对于学生奠定学科基础、培养学生对复合材料方向的兴趣具有重要的先导作用。笔者以"提升教学魅力,打造一门好课"为改革目标,充分贯彻了"教学内容是教学魅力的根本,教学方法与教学手段是将教学内容高效转化为教学魅力的催化剂"这一指导思想,从教学内容与教学方式两方面进行改革。从教学反馈看,这些改革措施能够改善教学效果,提高学生学习效率,得到了学生的认可。     

Strategies for multi-site GLP studies

 A GLP study can be performed at more than one site. This is called a multi-site study. Although, the study is performed at different sites, it is still one study and must completely comply with the GLP principles. The fact that different activities are conducted at different sites implies that the planning, the organization and the communication are crucial for the success of the study. This means that all the staff involved should know their responsibilities and should have the knowledge and skills to realize all the phases of the study according to the GLP principles. To achieve a well managed multi-site study, several strategies for setting up such a study can be followed. This paper focuses on the responsibilities, communication, and collaboration of the personnel, which are involved in a multi-site study. Several case studies are highlighted, and we concluded that the basic communication triangle in a single-site GLP study between test facility management, study director, and the quality assurance unit should be extended to the communication among test facility and test site management, study director, principle investigator(s), and the quality assurance units at the test sites. Introduction Received: 14 August 2002 Accepted: 26 November 2002     

Green chemistry and sustainability metrics in the pharmaceutical manufacturing sector

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Polymer Chain Conformation on Deuterated Polystyrene Nanoparticles Investigated by SANS

We previously reported that grafted polystyrene (PS) chains on silica nanoparticles at a low grafting density show similar conformations to free PS chains in the same solvent, THF (diameter ?50 nm, Colloid.poly.Sci. (2013), 291, 9, 2087–2099). As an extension of our previous study we choose an organic nanoparticle (deuterated polystyrene, dPS) instead of inorganic nanoparticle to see the impact of the substrate material on chain conformation. Additionally, a wider range of molecular weights were prepared to investigate the conformation feature of grafted PS chains more in detail. Small angle neutron scattering (SANS) experiments were performed to characterize PS grafted dPS particles in good solvent condition, with deuterated toluene and deuterated THF as solvent. To get insight into the conformation of the grafted PS layer we apply a scaling law describing the dimension of free PS polymer in good solvent condition to the obtained thickness of the grafted PS layer. We find an overall agreement with the scaling law where the thickness of the grafted PS layer is slightly larger than 2R_g of the free polymer chains in the respective solvent giving hint for semi dilute polymer brush (SDPB) situation.     

Some remarks on good sets

It is shown that (1) if a good set has finitely many related components, then they are full, (2) loops correspond one-to-one to extreme points of a convex set. Some other properties of good sets are discussed.     

恒加试验简单线性估计的改进

在恒加试验中加速方程的二个系数ａ与ｂ的估计最为重要。文中给出了参数ａ与ｂ的二种新的简单线性无偏估计（ＢＧＬＵＥ，ＲＧＬＵＥ），这两种无偏估计均比常用的二步估计有较大的改进。基于上述新的线性估计，文中还构造了二种新的线性不变估计（ＢＧＬＩＥ，ＲＧＬＩＥ）。这两种不变估计均优于文献（１）给出的简单线性不变估计。     

When isf(x1, x2, ..., xn) =u1(x1) +u2(x2) + ... +un(xn)?

We discuss subsetsS of ℝⁿ such that every real valued functionf onS is of the formf(x₁, x₂, ..., x_n) =u ₁(x₁) +u ₂(x₂) +...+u _n(x_n), and the related concepts and situations in analysis.     

Covering partially directed graphs with directed paths

We consider graphs which contain both directed and undirected edges (partially directed graphs). We show that the problem of covering the edges of such graphs with a minimum number of edge-disjoint directed paths respecting the orientations of the directed edges is polynomially solvable. We exhibit a good characterization for this problem in the form of a min-max theorem. We introduce a more general problem including weights on possible orientations of the undirected edges. We show that this more general weighted formulation is equivalent to the weighted bipartite b-factor problem. This implies the existence of a strongly polynomial algorithm for this weighted generalization of Euler's problem to partially directed graphs (compare this with the negative results for the mixed Chinese postman problem). We also provide a compact linear programming formulation for the weighted generalization that we propose.