甲烷卤代物热力学性质的拓朴指数计算

定义化学键特征值为iδj=|xi-xj|/(ni nj)0.85,分子化学键电负性连接指数nmY=∑(iδ.jδ…)。用0Y、(10Y)0.5和(33Y)0.25回归计算了70个甲烷卤代物的标准生成焓和生成自由能;单参数相关系数为0.997 6和0.998 2,三参数相关系数为0.999 0和0.998 6。     

不同载荷对45#钢表面自修复膜成膜影响

为制备在润滑油中具有良好分散性的自修复粉体和研究不同载荷对自修复膜成膜的影响,分析了钛酸酯偶联剂对蛇纹石粉体表面的修饰作用,探讨了不同载荷下添加剂对金属摩擦副的自修复作用,解析了试样表面形貌和试样表面化学成分.结果表明:经钛酸酯偶联剂修饰的粉体在润滑油中具有较好的分散性;在润滑油中加入蛇纹石粉体和分散剂可显著增加耐磨减摩性能.当载荷为300 N,含有添加剂的润滑油润滑条件下,摩擦副的摩擦系数较纯基础油低,添加剂起减摩作用;当载荷为600 N和900 N时,蛇纹石粉体在表面形成相对完整、光滑的自修复膜层,避免了金属表面的直接接触,从而起到降低磨损的作用;当载荷为900 N时,表面自修复膜层在摩擦机械力和热的作用下,发生化学脱水反应,自修复膜层表面有较多的微小孔洞.     

长春市产业空间布局演化:轨迹、机制与调控

产业空间结构是产业各部门、各要素、各环节在地域上的组合与分布.以长春市为研究对象,对长春市产业空间布局的发展轨迹进行了梳理,认为要素集散、因子促动、城市化载体以及政府调控是驱动长春市产业空间布局形成演化的主要机制.分析了城市产业布局的现状特征——产业发展的空间强势极化、产业空间集中-分散布局等,并进一步提出了长春市产业空间重组的演化趋势与调控路径.     

气体成分对介质阻挡放电中超四边形斑图的影响

采用介质阻挡放电装置,研究了1.01×105Pa下空气和氩气的混合气体中气体成分对超四边形斑图的影响.实验发现,随着空气体积分数的增大,产生超四边形斑图所需要的驱动电压也随之升高,同时,超四边形斑图越来越不稳定,放电丝直径逐渐变小,当空气体积分数大于4%时放电丝个数由每行6个增加到7个.     

区域高新技术产业发展的集群网络化模式

在对集群网络概念界定的基础上，通过对硅谷等几个具有代表性的高新技术产业集聚区成功经验的分析，认为成功的高新技术产业集聚区的成功并非区域内生产要素的简单叠加，而是区域内各种生产要素的有效组合及其形成的紧密集群网络．本文运用社会网络理论探讨了区域高新技术产业集群网络的层次结构及网络作用机制，基于集合论、拓扑学、分形几何构建了区域高新技术产业集群网络形成演化模型，并结合大连市高新技术产业发展实际，探讨了针对城市高新技术产业发展的集群网络化模式．     

Cesium accumulation by bacterium Thermus sp. TibetanG7： hints for biomineralization of cesiumbearing geyserite in hot sprinss in Tibet, China

The bacterium Thermus sp. TibetanG7, isolated from hot springs in Tibet, China, was examined for the ability to accumulate cesium from solutions. Environmental conditions were simulated and the effects of pH, K^＋, Na^＋and K^＋-regimes were then studied to determine the possible role of the bacterium in the formation of cesium-bearing geyserite around these hot springs. In despite of the inhibition of K^＋ and Na^＋, the bacterium Thermus sp. TibetanG7 revealed noticeable accumulation of cesium from solutions, with maximum accumulations of 53.49 and 40.41 pmol Cesium/g cell dry weight in Na^＋ and K^＋ inhibition experiments, respectively. The accumulation of cesium by this microorganism is rapid, with 40% --50% accumulated within the first 5 min. K^＋-deficient cells showed a much higher capacity of cesium accumulation compared with K^＋-sufficient cells. It is evident that the bacteria within the genus thermus play a significant role in the cesium assembly. The formation of cesium-bearing geyserite is also considered.     

Effects of nitrogen sources and glucose on the consumption of ethylene and methane by temperate volcanic forest surface soils

There is limited knowledge with regard to the consumption of ethylene (C2H4) and methane (CH4) in volcanic forest soils containing low microbial carbon-to-organic carbon ratio, and to the responses of both consumptions to nitrogen and carbon additions. Temperate volcanic forest surface soils under three forest stands (e.g. Pinus sylvestris L., Cryptomeria japonica and Quercus serrata) were used to compare CH4 and C2H4 consumption by forest soils, and to study the effects of nitrogen sources and glucose on both consumptions. There was a good parallel between CH4 and C2H4 consumption by for- est soils, but mineralization reduced CH4 consumption rather than C2H4 consumption in forest soils, particularly in a Pinus forest soil. The stimulatory effect of glucose addition on both CH4 and C2H4 consumption by forest soils was increased by increasing the pre-incubation period after glucose addi- tion, and a largest stimulation occurred in the Pinus forest soil. The addition of KNO3-N at the rate of 100 μg·g1 significantly reduced the consumptions of both C2H4 and CH4 by forest soils (P≤0.05). In the presence of urea plus dicyandiamide, the consumption rates of C2H4 and CH4 by forest soils were higher than those in the KNO3-N and urea-N treated soils at the same N rate (P≤0.05), but were similar to those of the control. Hence, under experimental conditions, there was a strong inhibitory effect of NO3 rather than NH4 addition on the CH4 and C2H4 consumption in these forest soils. When amount of the added NO3-N increased up to more than 2―3 times the soil initial NO3-N concentrations, both C2H4 and CH4 consumption rates were reduced to 10%―20% of the rates in soils without nitrate addition. By comparing the three forest stands, it was shown that there was a smallest effective concentration of the added nitrate that could inhibit C2H4 and CH4 consumption in the Pinus forest soil, which indicated that C2H4 and CH4 consumption of the soil was more sensitive to NO3-N addition.     

Chronological record of the Early Mesozoic underplating in the northern margin of North China—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 254 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic rocks.Compositions of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.     

鄂尔多斯盆地姬塬地区延长组碎屑岩储层低渗特征及含油性主控因素

鄂尔多斯盆地上三叠统延长组发育陆相坳陷型湖泊三角洲相低渗储层。在岩石薄片、铸体薄片、扫描电镜、X光衍射、自生伊利石K-Ar同位素测年等分析的基础上，对该地区延长组长6-长2段低渗致密储集砂体的岩石学特征、孔隙类型、物性特征、成岩动力学及孔隙演化特征进行了研究，并对低渗透储层的含油气性进行了分析。结果表明：①该组砂体以长石砂岩为主，次为岩屑砂岩和长石质岩屑砂岩，矿物成熟度低；②孔隙类型包括残余粒间孔、晶间孔、溶蚀孔和微裂缝，其中残余粒间孔是储层的主要储集空间；③主要成岩作用包括机械压实作用、溶蚀作用、碳酸盐胶结作用、自生粘土矿物胶结作用等，其中溶蚀作用产生的次生孔隙对储层物性的改善不足；④成岩作用开始较早、塑性岩屑颗粒大量变形、压实作用强烈是导致早期砂岩孔隙丧失的根本原因，碳酸盐岩胶结作用、次生孔隙不发育是造成后期储层岩石致密的主要因素。含油气性分析结果表明，砂体的不同沉积成因类型是层间含油气性差异的主控因素；同一成因砂体内部的非均质性是层内含油气性差异的主控因素。     

泥页岩井壁坍塌周期分析

应用力学／化学耦合理论对泥页岩井壁延迟坍塌机理进行了分析。以多孔介质渗流力学为基础，建立了近井壁地层孔隙压力的计算模型，计算了不同时期的临界坍塌压力，分析了钻井液物性参数对井壁稳定性的影响，得到了近井壁地层孔隙压力及强度参数在时空域内的分布，以及一定钻井液密度下泥页岩井壁坍塌破坏的时间。算例分析表明，在同一膜效率下，随着钻井液水活度增加，坍塌周期缩短；在同一钻井液水活度下，提高膜效率可以延长坍塌周期；钻井液水活度越小，膜效率的影响越显著。现场选择钻井液时，同时考虑水活度和膜效率并根据井壁坍塌压力改变钻井液密度，效果才会更好。