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Synthesis and Stereochemistry of New Cyclic Phosphate-phosphonates

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Chinese Chemical Letters 1997年第1期8卷 11-12页

作者： Zhou, J Chen, ry NANKAI UNIV NATL KEY LAB ELEMENTOORGAN CHEMINST ELEMENTOORGAN CHEMTIANJIN 300071PEOPLES R CHINA

The novel cyclic phosphate-phosphqnates,cis/trans-2-phosp dimethyl-1,3,2-dioxaphosphorinane 2-sulfides(selenides) (7a-f),were synthesized by a one-pot reaction using tris(diethviamino)phosphine activated by iodine as the phosphorylating and ring-closing reagent in good overall yields. The geometric stereoisomers were isolated and characterized. A cis-configuration and a chair preferred conformation of one isomer of 7b were established by X-ray diffraction analysis.

关键词： ACIDS

A Convenient Method for the Synthesis of 1,3,2-Oxazaphospholidin-[3,2-a]-8-oxo-10-thio(or seleno)-[1,3,2]-benzodiazaphosphorines

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Chinese Chemical Letters 2000年第10期11卷 867-870页

作者： Deng, SL Huang, JM Chen, ry Nankai Univ Natl Key Lab Elementoorgan Chem Inst Elementoorgan Chem Tianjin 300071 Peoples R China

A Convenient method for the synthesis of fused phosphorusheterocycle 1,3,2-oxazaphosphorin-[3.2-a]-8-oxo-10-thio(or seleno)-[1,3,2]-benzodiazaphosphorines was carried out in one pot by the reaction of Tris(diethylamino)phosphine with multifunctional compounds 2-(N-(beta or gamma-hydroxyl) alkylene) amino-benzamides 1. When PCL3 was used, only chlorinated product was obtained.

关键词： convenient method synthesis multifunctional compounds fused phosphorus heterocycle one-pot

Chiral separation of triazole pesticide enantiomers by high performance liquid chromatography

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Chinese Journal of Chemistry 1997年第6期15卷 528-533页

作者： Yang, GS Gao, ry Wang, QS Shen, HX Shandong Univ Dept Chem Jinan 250100 Shandong Peoples R China Nankai Univ Natl Lab Elementoorgan Chem Tianjin 300071 Peoples R China Nankai Univ Dept Chem Tianjin 300071 Peoples R China

Four triazole enantiomers of diclobutrazol (erythro form) (1), paclobutrazol (erythro form) (2), diniconazole (3) and uniconazole (4) have been separated by high performance liquid chromatography (HPLC) on chiral stationary phase (CSP) OA-4700. Chromatographic data, and a chiral recongnition model are presented for the separation of these pesticide enantiomers. The influence of column temperature and composition of mobile phase have been described.

关键词： triazole pesticide enantiomeric separation chiral stationary phase (CSP) high performance liquid chromatography (HPLC)

Synthesis of some new germasesquioxides by intramolecular catalytic Mannich-type reactions

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Chinese Journal of Chemistry 1997年第6期15卷 548-552页

作者： Zhang, ZB He, DY Chi, GC Chen, ry Nankai Univ Inst Elementoorgan Chem State Key Lab Elementoorgan Chem Tianjin 300071 Peoples R China

A convenient procedure for the preparation of some new germasesquioxides containing phosphonyl groups carried by an intramolecular catalytic Mannich-type reaction is reported.

关键词： germasesquioxide Mannich-type reaction synthesis

Analyses of plasma reactive sputter deposition of CN_x films by OES

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Chinese Science Bulletin 1997年第21期42卷 1792-1795页

作者： Zhao, J Kang, N Wang, JG Wang, ry Xu, JR Chinese Acad Sci Inst Phys Lab Opt Phys Beijing 100080 Peoples R China

OPTICAL emission spectroscopy (OES) is generally used in diagnosis on the various plasma filmdeposition processes to understand the mechanism of film growth. However, although the de-position precursors have been predicted such as CN radicals and nitrogen atoms, up tonow no diagnostic work on CN_x film deposition process, as we know, has been reported *** previously reported res.arch work, the properties of CN_x film display some obvious dif-ference. For instance, some CN_x films have extreme mechanical properties with hardness

关键词： carbon nitride fiim optical emission spectras optical gap.

A NEW. NEO-CLERODANE DITERPENE FROM AJUGA NIPPONENSIS

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Chinese Chemical Letters 1995年第7期6卷 581-582页

作者： Liu, Z Li, ZQ Zhang, CX Chen, ry Zhang, YG Qiu, YT Zhao, SH Nankai Univ Inst Elementoorgan Chem Tianjin 300071 Peoples R China S China Agr Univ Dept Plant Protect Lab Insect Toxicol Guangzhou 510642 Peoples R China

This paper describes the structural elucidation of a new insecticiaal neoclerodane diterpene Ajagamarin L-2 from Ajuga nipponensis,based on spectral data and X-ray diffraction analysis as 4,18-epoxy-6 alpha -hydroxy-1... 详细信息

关键词： NEO-CLERODANE DITERPENE FROM AJUGA NIPPONENSIS A NEW

SLIP SYSTEMS AND DISLOCATION DISTRIBUTION IN α-PHASE OF SUPERPLASTICALLY DEFORMED Ti-6AI-4V ALLOY

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Acta Metallurgica Sinica(English Letters) 1990年第4期3卷 256-261页

作者： ZHAO Linruo ZHANG Shaoqing YAN Minggao Institute of Aeronautical Materials,Beijing,China lab.No.4,Beijing Institute of Aeronautical Materials,Beijing 100095,China

The activated slip systems in the α-phase of the superplastically deformed Ti-6Al-4V alloy were analyzed by systematic operation method with *** results show that the dominately activated slip systems in the α-phase are{01(?)0}〈2(?)0〉and{01(?)}2(?)0〉, The{0001}〈2(?)0〉system as well as the c+a dislocalions of b=[1/3]〈11(?)3〉will be acti- vated when the deformation temperature is *** amounts of TEM observations in- dicate that the dislocations in the α-phase were mainly activated near the triple grain bounda- ry junctions,α/α grain boundaries and α/β interlaces.

关键词： titanium alloy superplastic deformation dislocation

A Decision Support Framework for the Choice of Languages and Methods for the Design of Real Time Embedded Systems

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Journal of Software Engineering and Applications 2016年第7期9卷 353-397页

作者： Valéry M. Monthe Laurent Nana Georges E. Kouamou Claude Tangha Department of Computer Science University of Yaounde 1 Yaounde Cameroon lab.STICC (UMR CNRS 6285) Department of Computer Science University of Brest Brest France Department of Computer Engineering National Advanced School of Engineering Yaounde Cameroon

The choice of methods or design languages is a crucial phase in the development of systems and software, also for real time and embedded systems. An open question that remains in the design of these types of systems is to build a method, or to choose one among those existing, capable to cover the life cycle of a project, and particularly the development phases. This article contributes to answer the question, by proposing an approach based on a multi-criteria comparative study, of few languages and methods dedicated to the design of real time and embedded systems. The underlying objective of this work is to present to designers a wide range of approaches, and elements that can guide their choices. In order to reach this goal, we propose different comparison criteria. Each criterion is divided into sub-criteria, so that the designers can refine their choices according to the qualities they prefer and wish to have in the method or language. We also define a rating scale which is used to assess the retained languages and methods. The scores obtained from this assessment are presented in tables, one table per criterion, followed by a summary table giving the overall scores. Graphics built from these tables are provided and intend to facilitate the judgement and thus the choice of the designers.

关键词： Design Method Modelling Language Real-Time System Embedded System Comparison Criteria

Mechanical Design and Preliminary Realization of Robotic Fish with Multiple Control Surfaces

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Mechanical Design and Preliminary Realization of Robotic Fis...