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11.
12.
Joris Van Loco Maureen Moerenhout Hedwig Beernaert 《Accreditation and quality assurance》2003,8(2):61-67
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 相似文献
13.
JieLiang Bi-qianLiu 《高分子科学》2005,(1):83-92
Plasma-induced surface graft copolymerization of acrylic acid on polypropylene non-woven fabric (PP-g-AA) and polypropylene membrane were reported. The extents of grafting were controlled by the plasma and polymerization condition. Hexadecyltrimethyl ammonium bromide was then coupled with the carboxyl group of PP-g-AA to obtain a polyion complex (PIC). At last, CF4 plasma was used to give PICs hydrophobic property. The moisture regain and water-repellency of the processed PICs was investigated. The surfaces were characterized using ATR FT-IR and XPS. The result indicates that the products have very high ability to adsorb moisture, even better than cotton fiber. At the same time, the products show excellent hydrophobic property, which can‘t be wetted by those reagents whose surface tensions were higher than 327mN/m. 相似文献
14.
L. S. Zakharov G. N. Molchanova T. M. Shcherbina P. V. Petrovskii M. I. Kabachnik 《Russian Chemical Bulletin》1998,47(9):1718-1724
A number of trialkylsilylmethyl diphenyl phosphates MeRR′SiCH2OP(O)(OPh)2 (1a-e: R=Et (a), Pr (b), CF3CH2CH2 (c, e), Me3SiCH2 (d); R′=Me (a-d), Et (e)) were synthesized and their thermal rearrangement, of the 1,2-shift type, was studied. The rearrangement consists of the
migration of an alkyl group from Si atom to the methylene carbon atom and gives the corresponding silyl esters. The rate of
the rearrangement was found to increase in the order1d<1b<1a<1 (R=R′=Me)<1c corresponding to the enhancement of the total inductive effect (−I) of the substituents at the Si atom. The relative migration ability of the substituents at the Si atom, determined by GC/MS
analysis of the disiloxane fraction resulting from hydrolysis of pyrolyzed phosphates1a-e, increases in the order R=Pr<Et<CF3CH2CH2<Me≪Me3SiCH2, which differs substantially from the order in which the rate of the rearrangement of phosphates1a-d changes. The electronegativity of the migrating group affects noticeably the relative ability to migrate.
For Part 4, see Ref. 1.
Deceased.
Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 1767–1772, September, 1998. 相似文献
15.
近红外(NIR)光谱技术可用于表征氯仿体系中反胶团增溶水的能力. 对于C12-s-C12•2Br (s=2, 3, 4, 5, 6, 8)系列, 不论体系是否含有NaBr电解质, 由于具有较短联接链的表面活性剂易形成较大的反胶团, 其增溶水的能力随着联接链长度增加而降低. 与未含NaBr电解质的体系相比, 当体系中存在NaBr电解质时所形成的反胶团增溶水能力降低. 相似文献
16.
1 INTRODUCTION During the study of polynuclear complexes with the aim to investigate the magnetic super-exchange interaction between the adjacent metal ions bridged by a conjugation molecule[1], we have made efforts to prepare complexes bridged by 4, 5-diazafluorene-9-one azine (DAA) and found that the coordination ability of DAA is poor in the acidic solution. In order to probe the reason, DAA has been crystallized from the hydrochloric acid solution and its crystal structure has b… 相似文献
17.
18.
Lamination Design Optimization for Continuous Fiber Reinforced Composites of Variable Thicknesses北大核心CSCD
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由于具备高的比强度、比刚度,利用连续纤维增强复合材料代替传统金属材料以实现结构轻量化正受到设计者们的广泛关注。然而,结构的复杂性给复合材料的铺层设计与优化带来了很大的挑战。针对航空用复合材料铺层设计约束多的问题,通过逐步构建设计变量准确表达结构的铺层信息。基于经典遗传算法框架,结合各设计变量特点,定义了铺层优化算法中的遗传算子,通过引入“修复”策略保证了每一代解都能满足设计约束,分布在可行域区间内。最后利用精英保留策略提高了算法的局部寻优能力,可以降低复杂复合材料结构铺层设计的计算成本。通过解决经典benchmark问题并与已有优化结果的比较,验证了前述铺层优化算法的全局、局部寻优能力,为工程实际中的复合材料铺层设计优化提供了理论支撑。 相似文献
19.
Sumitra Tavornvipas Hidetoshi Arima Fumitoshi Hirayama Kaneto Uekama Toshihiro Ishiguro Masahide Oka Kenichi Hamayasu Hitoshi Hashimoto 《Journal of inclusion phenomena and macrocyclic chemistry》2002,44(1-4):391-394
Some physicochemical and biological properties of a new branched cyclodextrin, 6-O--(4-O--d-glucuronyl)-d-glucosyl--cyclodextrin GUG--CyD) were investigated. Further, theinteraction of GUG--CyD with several drugs was studied by the solubility and spectroscopic methods, and compared with those of parent -CyD and 6-O--maltosyl--CyD(2--CyD).The hemolytic activity of GUG--CyD on rabbit erythrocytes was lower than those of -CyD and 2--CyD. GUG--CyD and 2--CyD showed negligible cytotoxicity on Caco-2 cells up to at least 0.1 M. The inclusion ability of GUG--CyD to neutral and acidic drugs was comparable to or slightly smaller than those of -CyD and 2--CyD, probably because of a steric hindrance of the branched sugar. On the other hand, GUG--CyD showed greater affinity for the basic drugs, compared with -CyD and 2--CyD, owing to the electrostatic interaction of its carboxylate anion with positive charge of basic drugs. Thus GUG--CyD may be useful as a safe solubilizing agent particularly for basic drugs. 相似文献
20.
The complex [Ru(II)(dcbpyH2)(bdmpp)NCS](PF6) (1) (where dcbpyH2 is 2,2′-bipyridine-4,4′-dicarboxylic acid, bdmpp is 2,6-bis(3,5-dimethyl-N-pyrazoyl)pyridine,) is synthesized and characterized extensively by 1H NMR and 13C NMR 1D and 2D, mass spectroscopy, cyclic voltammetry, electronic absorption spectroscopy and IR. The half-wave potential of the Ru(II)/Ru(III) redox couple was measured at E1/2=+0.795 V versus Ag/AgCl in CH3CN. The complex presents three intense metal-to-ligand charge transfer (MLCT) (dM→πL*) absorption bands centered at 383 (=21 300 M−1 cm−1), 432 (=22 400 M−1 cm−1) and 475 nm (=23 400 M−1 cm−1), respectively. The absorbance is extremely strong between 400 and 500 nm and even at 620 nm, the extinction coefficient is still high (=3768 M−1 cm−1). The strong π-acceptor property of the trans-isothiocyanate ligand compared with the Cl− ligand is probably the cause of the blue-shift observed in complex 1. These properties make the complex potentially promising for the photosensitization process. The incorporation of TiO2 photoelectrodes derivatized with this complex into a solar cell using a composite polymer/inorganic oxide solid-state electrolyte confirmed its sensitizing ability. Incident monochromatic photon-to-current conversion efficiency (IPCE) values of about 30% and overall energy conversion efficiency (η) of 1.7% were obtained. 相似文献