59 research outputs found

    化学实验教学中安全教育的探讨

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    实验安全教育是实验教学顺利进行和开展的首要保障。文中介绍了香港科技大学化学实验室中的安全教育情况和厦门大学在化学实验教学中对安全教育的改革探索与实践,其中主要包括硬件设施、软件学习和各自的特色,通过对比分析两校的共同点和差距,为进一步完善高校化学实验室安全教育提供参考

    Synthesis and Characterization of Ruthenium and Osmium Complex Containing Phosphine Ligands

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    摘要 近年,苯环中的一个CH瓣被过渡金属取代得到“金属苯”甚至“金属苯炔”类化合物的研究,受到越来越多合成者们的关注。在前人已报道的“金属苯”中,利用过渡金属与炔的环化作用合成“金属苯”的例子目前仅有两例,都是用两当量的乙炔参与环化反应。本论文首次报道用等当量的五碳双炔与锇配合物发生环化反应,制得了结构新颖的“锇苯”配合物。主要研究内容与结果如下: 通过配位不饱和的16电子锇配合物OsCl2(PPh3)3与五碳双炔有机化合物HC≡CCH(OH)C≡CH反应,再加入PPh3反应,直接关环制得新型“锇苯”配合物[Os(CHC(PPh3)CHC(PPh3)CH)Cl2(PPh3)2](OH)...Synthesis and Characterization of Ruthenium and Osmium Complexes Containing Phosphine Ligands Abstract Recently, more and more interests have been shown by the synthesist to the study on replacement of a CH group in benzene by an isolobal transition metal fragment together with its associated ligands to give metallabenzene even metallabenzyne complexes. Although many metallabenzene comple...学位:理学硕士院系专业:化学化工学院材料科学系_高分子化学与物理学号:19993600

    萘系高效减水剂的优化合成与改性

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    研究了工业萘系高效减水剂合成工艺的优化方案,得出了各合成阶段的关键工艺参数———时间、温度和原料用量的最佳控制值。尝试了一次性投酸法和用石灰代替液碱中和等新的工艺手段,前者可以简化合成工艺,但不会影响产品质量;后者不仅可以降低成本,而且所得产品除了用作减水剂,还可兼作加气混凝土的稳泡剂。对复合改性的研究发现,“萘系-糖钙”复合外加剂,既保持了显著的减水、增强效果,又达到了控制混凝土坍落度损失的改性目的

    Progress of Study on Linear Carbon Bridged Organometallic Molecular Wires

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    由过渡金属与线性有机共轭桥组成的“分子导线”以其在一维分子导体、液晶材料和非线性光学材料等方面的潜在应用价值引起学术界和产业界的关注 .结合自己在此方面所做的工作 ,从合成、性质等方面对近年来含线性碳桥金属有机“分子导线”的研究进展作一综述.The complexes containing C x and C x H x carbon chains spanning multi transition metals are of current interest due to their anticipated useful properties in molecular electronics and nonlinear optical materials. This paper reviewed the recent advances in this exciting field

    The Static Properties of AlN and GaN,and the Valence-band ofFsets of AlN/GaN Heterojunction

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    采用lMTO能带从头计算方法,计算了闪锌矿(立方)结构AIn和gAn的静态性质;用平均键能方法,预言了Aln与gAn自由应变生长、以Aln为衬底和以gAn为衬底等三种不同应变状态下Aln/gAn应变层异质结的△EV值;最后,采用超原胞(AIn)n(gAn)n(001),(n=1,3,5)界面自洽计算方法,考察了超晶格中平均键能EM的“对齐”程度和验证了价带偏移△EV计算结果的准确性。The static properties of cubic AlN and GaN (zinc-blende structure) are calculated by ab initio LMTO method.Using average bonding energy method,the valence-band ofFsets of AlN/GaN strained layer heterojunction under three strained conditions (i.e.growing GaN layer on substrate of AlN,growing AlN layer on substrate of GaN,and AlN and GaN strained Freely to Form the hetero-junction) are predicted.Finally, the calculated results of valence-band ofFsets △Ev and the "alignment" of average bonding energy Em in strained layer superlattice (AlN )n (GaN)n (001), (n = 1,3, 5) are veriFied by supercell selF-consistent calculation.福建省自然科学基

    Electronic Structure of Strained layer Superlattice GaN AlN

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    采用有效质量理论6带模型,计算了应变层超晶格gAnAln(001)的电子结构,具体计算不同应变状态的价带子能带色散曲线、光吸收曲线。分析了应变状态以及重轻空穴和自旋轨道分裂带相互作用对子带结构的影响。The electronic structure of strained layer superlattice GaN AlN(001) has been studied within framework of the 6 band Luttinger model in the effective mass theory. The valence band structure and the absorption spectra for different strain conditions are calculated. The effects of strain and coupling among heavy hole, light hole, and spin split off bands on valence band structure are discussed.福建省自然科学基金;厦门光电子工业部资

    Calculation of Optical Properties of Zinc blende GaN,AlN and Their Alloys Ga 1 x Al x N

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    闪锌矿结构gAn、Aln和合金gA1-XAlXn光学性质计算何国敏王仁智郑永梅(厦门大学物理学系厦门361005)随着人们对发光二极管和半导体激光器等光电器件的深入研究,工作于蓝紫波段的半导体材料受到普遍的重视.宽带隙半导体gAn和Aln正是目前蓝紫...The nonlocal empirical pseudopotential method has been used to calculate the electronic structure of GaN, AlN and their alloys Ga 1 x Al x N .The imaginary part of the dielectric function of alloys Ga 1 x Al x N is also calculated with the virtual crystal approximation,and its trend versus Al fraction x are also discussed.国家和福建省自然科学基金;厦门大学光电子公司工业部资

    Rigid rod-like organometallic polymers

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    综述了在主链上含有过渡金属和刚性共轭有机桥的聚合物,即所谓的刚性棒状金属有机聚合物的种类、制备、性质及应用。This paper summarizes the organic bridge polymers that contain transition metals and rigid rod-like organometallic polymers, i.e the categories, preparation, properties and application of the rigid rod-like organometallic polymers

    含钛聚碳硅烷的合成、表征及其形成机理研究

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    以合成聚碳硅烷的副产品——液态小分子聚碳硅烷(LPCS)和钛酸正丁酯为原料,合成含钛聚碳硅烷,并通过产物的凝胶液相色谱、核磁、红外等表征方法研究其反应机理。研究表明,液态小分子聚碳硅烷的Si—H基团受热分解所形成的自由基,部分相互偶联,另一部分则与钛酸丁酯发生自由基取代反应,从而形成含钛聚碳硅烷,并因链的增长,分子量相应增大,最终形成主分子链由支化或交联度较高的链段所组成的含钛聚碳硅烷,具有较高的陶瓷产率,可以用作SiC陶瓷的先驱体
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