窄分布十二醇醚羧酸钠盐的合成及性能

以窄分布十二醇聚氧乙烯(2)醚 (AEO2)为原料经羧甲基化法合成了窄分布十二醇醚(2)羧酸钠盐(AE2C),经单因素实验对反应温度、投料比及反应时间等参数进行探讨,得出最佳的合成工艺条件为:n(AEO2):n(ClCH2COOH):n(NaOH)=1:1.1:2.2,反应温度70℃,反应时间5h.经分离提纯后对产品进行红外结构表征和活性含量测定,并对其表面张力、泡沫性、润湿性、乳化性、钙皂分散力和去污力进行了测试.结果表明,合成的AEC阴离子活性含量为 87.38%, CMC为 0.41 mmol/L,最低表面张力为 25.4 mN/m,泡沫性(0.1% 溶液)83ml、润湿性(0.1% 溶液)5.1s、乳化性(液体石蜡)131.8s、钙皂分散力LSDP 16和去污力(0.25% 溶液)47.2%.     

基于DEA模型的中原城市群城市效率研究

运用数据包络分析方法,对2012年中原城市群9个城市的城市效率进行定量研究.结果表明:郑州、洛阳和济源的城市效率达到最优,处于高水平阶段;平顶山、新乡的城市效率均在0.90以上,城市效率水平较高;漯河、许昌的城市效率水平处于中等;开封和焦作的城市效率则位于低水平阶段.通过对各市的投入产出分析发现,郑州、洛阳、济源3个城市的资源投入量和产出量为合理值,而平顶山、新乡、漯河、许昌、开封和焦作均存在不同程度的投入冗余现象.     

Lagrange型余项中θ极限问题的进一步研究

利用Taylor公式对Lagrange及Taylor中值定理中Lagrange型余项的θ极限问题进行了定量研究.通过对f(x)在x=x0点的某个邻域内低阶可导情形的研究推广到n阶连续可导的情形,进而得到一般性的结论.     

风电场向孤岛输电的VSC-HVDC Light的建模与仿真

介绍了以VSC控制为基础的HVDC Light的系统结构和工作原理,在MATLAB中创建了风电场向孤岛输电的VSC-HVDC Light系统仿真模型,并对其进行了稳态仿真研究.对仿真结果进行分析可知,系统直流电压基本稳定在给定的电压值,两端直流电压实现了协调配合,有功功率实现了协调控制和自动平衡传输,各状态量都符合理论值,模型准确模拟出了VSC-HVDC Light系统的稳态工作状况,为实际工程提供了科学的理论依据.     

广西龙湾铅锌矿床矿石矿物组构特征及成矿阶段划分

通过井下的详细勘查和显微镜下鉴定,对广西龙湾铅锌矿床的矿石组构特征进行了系统研究.矿区矿石构造主要为块状构造、浸染状构造、网脉状构造和斑杂状构造;结构主要为结晶作用和交代作用形成的结构,其次为固溶体分离作用、结晶物质重结晶作用和压力作用形成的结构.同时将成矿期次分为沉积成岩期、中低温热液成矿期和表生氧化期,其中热液成矿期是矿床的主要成矿期.根据矿物组合特征,将成矿划分为五个成矿阶段,分别是黄铁矿-石英-方解石阶段、闪锌矿-方铅矿-黄铁矿阶段、黄铁矿-闪锌矿-方铅矿-黄铜矿阶段、石英-方解石阶段、氧化物阶段.矿物的生成顺序为黄铁矿1-闪锌矿(黄铜矿1)-方铅矿-黄铁矿2-黄铜矿2.最终确定龙湾矿床为受构造活动控制的中低温热液充填交代-叠生改造型多金属矿床.     

Mineralization of flue gas CO2 with coproduction of valuable magnesium carbonate by means of magnesium chloride

CO2 mineralization and utilization is a new area for reducing the CO2 emissions. By reacting with natural mineral or industrial waste, CO2 can be transformed into valuable solid carbonate （such as calcium carbonate or magnesium carbonate） with recovery of some products simultaneously. In this paper, a novel method was proposed to mineralize CO2 by means of magnesium chloride with small energy consumption. In this method, magnesium chloride was firstly transformed into magnesium hydroxide by electrolysis. The formed magnesium hydroxide showed high reactivity to mineralize CO2. In our study, even at low concentration, CO2 can be effectively mineralized by this method, which makes it possible to directly mineralize flue gas CO2, avoiding the expensive process of CO2 capture and purification. Moreover, valuable products such as hydromagnesite and nesquehonite can be recovered by this method. Because of the wide distribution of magnesium chloride in nature, largescale CO2 mineralization is potential by means of magnesium chloride.     

Finite element models and molecular dynamic simulations for studying the response of mast cell under mechanical activation

In micropipette aspiration experiment, increasing mechanical stress applied to cell membrane induced degranulation of mast cell as well as a current that could be inhibited by an inhibitor, which is specific for the transient receptor potential vanilloid （TRPVs） channels. To determine the sensitivity of TRPVs to membrane strain and tension, and to gain new insights into the activation mechanism of TRPVs, finite element models of mast cell and molecular dynamic simulations of human aquaporin-1 are presented. During the finite element simulations, the cell membrane sustained to micropipette aspiration was simulated, and the strain distribution along membrane thickness direction was obtained. Besides, combining the finite element models of osteoblast aspirated into micro- pipette and other compared models, we examined the relationship between cell mechanical stimulations and mechanical attributes and presented a new perspective to determine the cell equivalent elastic modulus. Consid- ering the indetermination of TRPV crystal structure, human aquaporin-1, one kind of the channel membrane proteins, substituting for TRPV, has been studied with molecular dynamic （MD） simulations, under different external lateral tensions which have been obtained in mast cell finite ele- ment simulations, to investigate the mechanical stimulation effects on the membrane channels. The simulations show that human aquaporin-1 undergoes significant conforma- tional change and expands in accordance with lateraltension, which not only confirms the tendency of the pre- vious electrophysiological experiments but also leads us to a better understanding of TRPVs. The multi-scale study combining finite element simulation and MD simulation is a significant breakthrough in the field of mechanical mechanism in cell system.     

Opening of the Longmu Co–Shuanghu–Lancangjiang ocean:constraints from plagiogranites

This paper reports new zircon U-Pb ages,and Hf isotope and whole-rock major and trace element data for Cambrian plagiogranites from the Tuobeiling ophiolite in central Qiangtang,Tibetan Plateau.Zircon SIMS and LAICP-MS U-Pb dating of the plagiogranites yield weighted mean ages of 504.8±4.2 and 491.6±1.5 Ma,respectively.The zircons from plagiogranites exhibit positive eHf(t)values(ranging from 11.46 to 15.16),indicating that the plagiogranites are derived from depleted mantle.These plagiogranites are characterized by high SiO2and Na2O,low K2O,low REE contents,and flat REE distribution patterns.These rocks have geochemical compositions typical of oceanic plagiogranite and,considered along with their petrography and field relationships,are interpreted to have derived from anatexis of hydrated amphibolites by ductile shearing during transports of the oceanic crust.The formation age of such type of plagiogranite is slightly younger than that of the associated section of oceanic crust.Thus the new results from these plagiogranites suggest that the Longmu Co–Shuanghu–Lancangjiang ocean had probably opened before the Middle Cambrian.     

Gold nanorod translocation through a solid-state nanopore

Recently, nanopores have been used in an essential technique for detecting single molecule with high sensitivity. The initial application of nanopores to DNA and RNA sequencing has been expanded to sensing pro- teins and nanoparticles, including Bovine serum albumin, silica nanoparticles, polystyrene beads, and others. In our study, for the first time, a positively charged gold nanorod was investigated using a solid-state nanopore device. Various gold nanorods passed through the nanopore with different current blockages and duration times, providing a measurement of the nanorod diameter, length, and charge. Our findings indicate that nanopore sensing might be a new method for characterizing the size, shape, and charge of nanoparticles.     

Millennial climate changes since MIS 3 revealed by element records in deep-sea sediments from northern South China Sea

High resolution elemental MD05-2903 from the northern South records in core China Sea were obtained from XRF scanning and grain size and mineral component analyses. The K/Ti curve reveals climate changes since MIS 3 on a millennial scale, representing one of the best such records so far from deep-sea sediments of the South China Sea. When compared our K/Ti record with other climate records from high latitude ice cores and from East Asia stalagmites, variations in the K/Ti record show some typical saw-shaped features of rapid climate changes in the Northern Hemisphere. Grain size analysis reveals a close relationship between variations in K/Ti and in the fine end-member grain size. XRD analysis confirms that high K/Ti layers were dominated by K-rich weathering minerals, especially illite, while low K/Ti layers contain low illite but high abundance of Ti-rich heavy minerals. Therefore, the K/Ti record reflects changes in the input and deposition of fine weathering minerals and heavy minerals in the northern South China Sea region during stadials and interstadials. These elemental changes were largely con- trolled by variations in rainfall, erosion, and fluvial trans- portation induced by East Asia Monsoon.