湖南芙蓉锡矿床^40Ar/^39Ar同位素年龄及地质意义

文章以金云母、角闪石和白云母为测试对象，利用^40Ar／^39Ar同位素定年的方法，精确厘定了芙蓉超大型锡矿床的形成时间。研究结果表明，白腊水矿区3个金云母样品的^40Ar／^39Ar坪年龄分别为（150．6±1．0）Ma、（157．3±1．0）Ma和（154．7±1．1）Ma；热液成因角闪石的坪年龄为（156．9±1．1）Ma。淘锡窝矿区云英岩中2个白云母样品的^40Ar／^30Ar坪年龄为（159．9±0．5）Ma和（154．8±0．6）Ma;因此芙蓉矿床的形成时间为151～160Ma，这与骑田岭主体花岗岩的侵入时间（151～162Ma）相吻合。湘南地区的柿竹园超大型W-Sn-Mo-Bi-F矿床、新田岭大型W矿床、瑶岗仙W矿床和黄沙坪Pb-Zn多金属矿床的形成时间亦集中在150～160Ma之间，因此，湘南有色金属矿化集中区可能主要集中在150～160Ma发生成矿，这种大规模成矿作用可能与中生代华南岩石圈的拉张、伸展作用密切相关.

可见光响应光催化剂K4Ce2M10O30（M=Ta, Nb）及其光解水特性的研究

氢能已被广泛认为是最具有潜力解决能源危机和环境问题的理想替代能源之一，其开发备受各个领域科学家的重视，更是从根本上解决环境地球化学工作者的主要目标：对已被破坏的环境和生态进行修复以及对可能破坏环境与生态的人类活动进行干预和指导。在众多的氢能开发手段中，利用太阳能光催化分解水制取氢气是一种兼顾能耗、资源和环境的最为理想和最有前途的氢能开发手段之一。在光催化分解水过程中，最为首要的研究内容就是开发具有适宜能带结构能响应可见光，稳定地、高量子效率地光解水的固相半导体光催化剂。 本论文中，通过高温固相反应合成了呈四方晶系钨青铜结构的半导体光催化剂K4Ce2M10O30(M=Ta, Nb)，吸收边分别达到580 nm (M＝Ta) 和690 nm (M＝Nb)，对应带隙为2.2 eV和1.8 eV。可见光下（λ> 420 nm）光催化分解H2O产生H2和O2的活性表明它们不仅有适宜的带隙响应可见光，并且其价带和导带位置能满足完全分解水的电化学电位需要。在担载Pt、RuO2以及NiO（NiOx）等助催化剂对产氢性能有显著的提高。同时以乙醇钽和草酸铌可溶性前驱体，分别通过溶胶凝胶法（Sol-gel）和聚合物络合法(Polymerizable Complex)制备了K4Ce2Ta10O30和K4Ce2Nb10O30。通过湿法化学合成的光催化剂显示了更高的光催化活性，并且通过PC法制备的K4Ce2Nb10O30更是实现了在大于300 nm 的光辐射下完全分解纯水产生摩尔比为约2:1 的H2和O2。 通过高温固相反应得到Nb取代K4Ce2Ta10O30中部分晶格Ta形成的单相无限固溶体系列K4Ce2Ta10-xNbxO30（x=0~10）是结构一致的同系物，吸收边介于540 nm～710 nm 之间，并且随着x的增加，吸收边依次红移，光催化产氢活性依次降低，但是x=2，5，8时的产氧活性比x=0和10的高，光催化活性的差异主要源于它们光吸收特性和能带结构的差异。基于密度范函理论DFT的第一性原理计算结果表明，光催化剂K4Ce2M10O30(M=Ta, Nb)的能带结构为：导带主要由Ta 5d (Nb 4d)组成，处于高能级的电子未占据态的Ce 4f 与其有很明显的重迭，但由于其高度局域特性，不能很好地参与光生电子在导带的传导，从而其对光催化活性的贡献很小，而价带则由O 2p与Ta 5d (Nb 4d)以及电子占据态的Ce 4f杂化轨道组成。同时通过高温固相反应合成了系列含稀土元素的光催化剂K4Re2M10O30(Re=La, Ce, Nd, Sm, Y; M=Ta, Nb)，通过对它们及其前驱体氧化物的光吸收特性以及电子结构的第一性原理计算研究，合理的解释了只有当Ln＝Ce时才具有可见光响应特性的微观机理。

四川省拉拉铜矿床岩石学及地球化学研究

拉拉铜矿床位于扬子地块西缘的康滇隆起中段，赋存于经历变质的古元古代河口群海相火山-沉积岩系中，是我国重要的受变质热液叠加或改造的火山成因块状硫化物矿床（VHMS）之一，也是四川省最大的铜矿生产基地。本论文以该矿床为研究对象，在系统整理前人资料的基础上，进行了深入细致的野外地质考察和系统采样，选取代表性样品，运用电子探针分析技术、元素地球化学、同位素地球化学（Rb-Sr、Sm-Nd、S）、锆石U-Pb定年等方法手段，对矿区新元古代大规模区域变质作用的变质条件、变质原岩、广泛分布于矿区多个赋矿层位的辉长辉绿岩脉、岩石及矿石性质、硫源、成矿时代等主要岩石学及矿床学问题进行了系统研究，并结合前人研究成果，探讨了矿床的成因机制。论文主要取得以下几点认识： （1）矿区变质火山岩的成岩年龄为1695±20Ma，岩浆在上升侵位的过程中捕获了古元古代早期地壳物质，后期变质改造的时代约为700-800Ma。 （2）基于石榴石黑云母片岩中石榴石黑云母矿物对的电子探针分析数据，利用石榴石-黑云母地质温度计和多硅白云母地质压力计确定了矿区新元古代大规模区域变质作用的变质条件：变质温度为530-580℃，变质压力上限为0.66-0.76GPa，对应于高绿片岩相。 （3）矿区出露的岩石类型以云母片岩类和钠长岩类岩石为主，二者共同构成了矿区的围岩及赋矿岩石，通过对代表性样品的元素地球化学、同位素地球化学研究，采用DF函数判别法、(Al/3-K)-(Al/3-Na)图解法、La/Yb-TR图解法，并结合岩矿鉴定及结构构造特征，恢复了矿区的变质原岩。其中，矿区的云母片岩类样品的变质原岩为沉积岩，以页岩为主，主要来自大陆岛弧及上地壳物质的风化；而钠长岩类样品的变质原岩为火山岩，源自富集地幔，包括“右倾型”钠长岩和“平坦型”钠长岩，前者为分离结晶作用早期并经历一定程度地壳混染的产物，后者主要形成于分离结晶作用晚期，Nb、Ta、Zr、Hf、P、Ti等达到饱和并以副矿物晶出。 （4）综合矿区变质沉积岩及变质火山岩的构造环境判别结果，确定了二者形成于大陆岛弧的弧后盆地环境。 （5）通过对矿区变质火山岩性质、形成机制及硫同位素研究，讨论了矿床中成矿元素可能的富集机制，即地幔中大量的亲铜元素及硫元素进入母岩浆并随之上升形成区域分布的火山岩，为矿床的形成提供了必要条件。 （6）侵入河口群地层并广泛出露于矿区多个赋矿层位的辉长辉绿岩脉的化学成分与板内碱性玄武岩类似且形成于大陆裂谷环境下的类似OIB源区，是高温地幔柱部分熔融的产物，幔源岩浆在上升侵位过程中受到了地壳物质尤其是上地壳物质较小程度的混染，表明新元古代Rodinia超大陆裂解对拉拉地区的成矿作用有重要影响。 （7）拉拉铜矿床主要存在两个成矿期次，即火山喷气-沉积成矿期（1700 Ma左右）和变质热液成矿期（700-800Ma）。矿区主要存在两种类型矿石，即条纹、条带状矿石和块状、浸染状矿石，前者主要赋存于变质火山岩中，可能形成于火山喷气-沉积成矿期，后者主要赋存于变质沉积岩中，可能为变质热液成矿期的产物。

高压差热分析方法（HP-DTA）研究钙蒙脱石-氯化钙-水体系中的脱水作用

在开放（P_水580 - 5.831 * (1000/T) (16.9M) 30%: 1np = 14.412 - 5.519 * (1000/T)根据这些等式求出了在不同压力、温度下各种浓度的CaCl_2-H_2O流体的水逸度系数（￡）。由于至目前为止在文献中还没有这方面的实验研究报道，因而无法评价这一新方法所获得的数据的准确性。利用求得的￡值，在本篇论文中建立起了不同浓度的CaCl_2-H_2O流体影响钙蒙脱石脱水温度的热力学模式：TD' = [T_1*T_D*(ΔH_(tw) + ΔH_(sv)~盐）/[T_1*(ΔG + ΔH_(dn)~水）-T_D~* (ΔH_(av)~水-ΔH_(sv)~盐）在0-1M浓度范围内，可以认为ΔH_(dh)~水≈H_(dh)~盐，等式变为：TD' = (TD*ΔH_(dh))/(ΔG + ΔH_(dh)）根据这个模式，能推导出在实验浓度范围内，钙蒙脱石在盐水体系中的脱水温度。通过本次论文的实验研究知道在一般沉积盆地的埋芷条件下，钙蒙脱石矿物不会发生简单的脱水作用。在缺乏K~+和低盐度的环境中，含水相蒙脱石可稳定地存在在一定深度的地壳中因而不可忽略蒙脱石在海洋化学和俯冲带水来源中的作用。在选择处理簇射性废料的回填料（backfill）时，如其它条件相同，则应优先选择钙蒙脱石，而不是蛭石。在石油采矿和勘探工程中，因压力释放所造成的蒙脱石的脱水作用可能是使钻井变大和塌方的可能性原因之一。

长江水环境的地球化学初步研究

1）长江沿程水溶态#delta#~(34)SO~(2-)_4的变化范围为-3.474～+5.938 per thousand，算术平均值为2.254 per thousand；悬浮态#delta#~(34)S之间的变化范围为-4.031 approx +4.580 per thousand。长江中水溶态#delta#~(34)SO~(2-)_4与悬浮态#delta#~(34)S之间存在相关性；2）根据长江中水溶态#delta#~(34)SO~(2-)_4的平均和它的径流量，估算中国河流#delta#~(34)SO~(2-)_4的加权平均值为+2.7 per thousand。结合中国长江、黄河的硫同位素组成和亚洲其它主要河流水溶态SO~(2-)_4的含量，推测亚洲河流的#delta#~(34)SO~(2-)_4加权平均值可能为+5 per thousand；3）长江流域内的区域地质条件决定了河流悬浮物中稀土元素和微量元素的背景含量－－悬浮物中稀土元素和大多数微量元素的含量为东高西低；4）悬浮物中大多数元素的含量随时间的变化基本保护不变，其变化幅度在自然波动范围之内；而砷元素在悬浮物中的含量随时间有明显的增高趋势，这显示了长江流域内的As污染源的增加。

Surface structure and reaction performances of highly dispersed and supported bimetallic catalysts

Surface structures of Pt-Sn and Pt-Fe bimetallic catalysts have been investigated by means of Mossbauer spectroscopy, Pt-L-III -edge EXAFS and H-2-adsorption. The results showed that the second component, such as Sn or Fe, remained in the oxidative state and dispersed on the gamma-Al2O3 surface after reduction, while Pt was completely reduced to the metallic state and dispersed on either the metal oxide surface or the gamma-Al2O3 surface. By correlating the distribution of Pt species on different surfaces with the reaction and adsorption performances, it is proposed that two kinds of active Pt species existed on the surfaces of both catalysts, named M-1 sites and M-2 sites. M-1 sites are the sites in which Pr directly anchored on the gamma-Al2O3 surface, while M-2 sites are those in which Pt anchored on the metal oxide surface. M-1 sites are favorable for low temperature H-2 adsorption, and responsible for the hydrogenolysis reaction and carbon deposition, while M-2 sites which adsorb more H-2 at higher temperature, are more resistant to the deactivation due to less carbon deposition, and provide major contribution to the dehydrogenation reaction.

Diseño, asistencia técnica en sistema de broches y acabados en piezas de joyería colombiana.

[286] hojas.

A brief history of the Bhopal principality in Central India : from the period of its foundation, about one hundred and fifty years ago, to the present time.

http://www.archive.org/details/briefhistoryofth014373mbp

Optimisation of Smart Grid performance using centralised and distributed control techniques

A massive change is currently taking place in the manner in which power networks are operated. Traditionally, power networks consisted of large power stations which were controlled from centralised locations. The trend in modern power networks is for generated power to be produced by a diverse array of energy sources which are spread over a large geographical area. As a result, controlling these systems from a centralised controller is impractical. Thus, future power networks will be controlled by a large number of intelligent distributed controllers which must work together to coordinate their actions. The term Smart Grid is the umbrella term used to denote this combination of power systems, artificial intelligence, and communications engineering. This thesis focuses on the application of optimal control techniques to Smart Grids with a focus in particular on iterative distributed MPC. A novel convergence and stability proof for iterative distributed MPC based on the Alternating Direction Method of Multipliers is derived. Distributed and centralised MPC, and an optimised PID controllers' performance are then compared when applied to a highly interconnected, nonlinear, MIMO testbed based on a part of the Nordic power grid. Finally, a novel tuning algorithm is proposed for iterative distributed MPC which simultaneously optimises both the closed loop performance and the communication overhead associated with the desired control.

The impact of shame on health-related quality of life among HIV-positive adults with a history of childhood sexual abuse.

Childhood sexual abuse is prevalent among people living with HIV, and the experience of shame is a common consequence of childhood sexual abuse and HIV infection. This study examined the role of shame in health-related quality of life among HIV-positive adults who have experienced childhood sexual abuse. Data from 247 HIV-infected adults with a history of childhood sexual abuse were analyzed. Hierarchical linear regression was conducted to assess the impact of shame regarding both sexual abuse and HIV infection, while controlling for demographic, clinical, and psychosocial factors. In bivariate analyses, shame regarding sexual abuse and HIV infection were each negatively associated with health-related quality of life and its components (physical well-being, function and global well-being, emotional and social well-being, and cognitive functioning). After controlling for demographic, clinical, and psychosocial factors, HIV-related, but not sexual abuse-related, shame remained a significant predictor of reduced health-related quality of life, explaining up to 10% of the variance in multivariable models for overall health-related quality of life, emotional, function and global, and social well-being and cognitive functioning over and above that of other variables entered into the model. Additionally, HIV symptoms, perceived stress, and perceived availability of social support were associated with health-related quality of life in multivariable models. Shame is an important and modifiable predictor of health-related quality of life in HIV-positive populations, and medical and mental health providers serving HIV-infected populations should be aware of the importance of shame and its impact on the well-being of their patients.

Pathogenicity of Salmonella: SopE-mediated membrane ruffling is independent of inositol phosphate signals

Studies [Zhou, D. Chen, L.-M. Hernandez, L. Shears, S.B. and Galán, J.E. (2001) A Salmonella inositol polyphosphatase acts in conjunction with other bacterial effectors to promote host-cell actin cytoskeleton rearrangements and bacterial internalization. Mol. Microbiol. 39, 248-259] with engineered Salmonella mutants showed that deletion of SopE attenuated the pathogen's ability to deplete host-cell InsP5 and remodel the cytoskeleton. We pursued these observations: In SopE-transfected host-cells, membrane ruffling was induced, but SopE did not dephosphorylate InsP5, nor did it recruit PTEN (a cytosolic InsP5 phosphatase) for this task. However, PTEN strengthened SopE-mediated membrane ruffling. We conclude SopE promotes host-cell InsP5 hydrolysis only with the assistance of other Salmonella proteins. Our demonstration that Salmonella-mediated cytoskeletal modifications are independent of inositolphosphates will focus future studies on elucidating alternate pathogenic consequences of InsP5 metabolism, including ion channel conductance and apoptosis.

On the contribution of stereochemistry to human ITPK1 specificity: Ins(1,4,5,6)P4 is not a physiologic substrate

Ins(1,4,5,6)P4, a biologically active cell constituent, was recently advocated as a substrate of human Ins(3,4,5,6)P4 1-kinase (hITPK1), because stereochemical factors were believed relatively unimportant to specificity [Miller, G.J. Wilson, M.P. Majerus, P.W. and Hurley, J.H. (2005) Specificity determinants in inositol polyphosphate synthesis: crystal structure of inositol 1,3,4-triphosphate 5/6-kinase. Mol. Cell. 18, 201-212]. Contrarily, we provide three examples of hITPK1 stereospecificity. hITPK1 phosphorylates only the 1-hydroxyl of both Ins(3,5,6)P3 and the meso-compound, Ins(4,5,6)P3. Moreover, hITPK1 has >13,000-fold preference for Ins(3,4,5,6)P4 over its enantiomer, Ins(1,4,5,6)P4. The biological significance of hITPK1 being stereospecific, and not physiologically phosphorylating Ins(1,4,5,6)P4, is reinforced by our demonstrating that Ins(1,4,5,6)P4 is phosphorylated (K(m) = 0.18 microM) by inositolphosphate-multikinase.

Micromagnetic simulation of domain walls in iron films

The micromagnetic structure and energy of 180° domain walls spanning laminar crystals of iron having (100) or (110) surfaces and ranging in thickness from 145 to 580 nm have been investigated by numerical integration of the Landau-Lifshitz-Gilbert equation. Stable equilibrium structures with two flux symmetries were obtained for both crystal orientations at all thicknesses studied.

Two-stage open shop scheduling with a bottleneck machine

It is known that for the open shop scheduling problem to minimize the makespan there exists no polynomial-time heuristic algorithm that guarantees a worst-case performance ratio better than 5/4, unless P6≠NP. However, this result holds only if the instance of the problem contains jobs consisting of at least three operations. This paper considers the open shop scheduling problem, provided that each job consists of at most two operations, one of which is to be processed on one of the m⩾2 machines, while the other operation must be performed on the bottleneck machine, the same for all jobs. For this NP-hard problem we present a heuristic algorithm and show that its worst-case performance ratio is 5/4.