支链化聚铵盐及其在压裂和酸化作业中的应用

制备了支链化聚铵盐系列化合物,评价了其在清水、胍胶液和盐酸溶液中对粘土膨胀的抑制作用,并对微观结构进行了分析。结果显示:在最佳制备条件下0.5%BPM-7溶液中90min时粘土的线性膨胀率为50.0%;BPM-7与胍胶的配伍性良好,能够强化胍胶液的抑制性,在酸液中也有较强的粘土稳定作用。支链化聚铵盐可通过离子交换取代粘土中原有的金属阳离子进入粘土层间,从而抑制水分子水化分散粘土,保持粘土层间距和颗粒的结构。作为粘土稳定剂应用于某气田酸化作业,能有效保护储层,作业后产气量显著提升。     

Who Experiences Foreclosures? The Characteristics of Households Experiencing a Foreclosure in Minneapolis,Minnesota

Much of the existing research on disparities in residential foreclosures provides strong, but not conclusive, evidence that minority households disproportionately experience foreclosures. Data commonly used in foreclosure research do not allow researchers to use household characteristics of foreclosed properties to test for disparities in experiencing foreclosure. This is a significant omission in the literature since understanding the types of households that most typically experience foreclosure might result in the creation of better targeted and more effective foreclosure prevention and mitigation programs. Using a unique data set this paper explores the characteristics of households that experienced a foreclosure in Minneapolis, Minnesota during fiscal years 2006 and 2007. Research results confirm that African American households disproportionately experience foreclosures, but also indicate that renter households, households with children and foreign-born homeowners are all over-represented among foreclosed households. These results have implications for how policy makers and practitioners address foreclosure prevention and mitigation efforts.     

The Distribution Characteristics and Geological Significance of Inclusion Trace Elements in Silurian Oil-containing Sandstones in the Central Tarim Basin

Trace elements of fluid inclusion in 16 Silurian oil-containing sandstones from 10 wells in Tazhong area were performed by inductively coupled plasma mass spectroscopy (ICP-MS), the distribution characteristics were analyzed, and their demonstrative geological significance was deeply discussed. The results show that the abundance of trace element varied markedly in the same well field or different well fields, the distribution rule of the main trace elements is that the abundance is increasing as a whole from down structure location to structural high. Variation characteristics of single trace element are consistent with the trace element suite, which reflects Silurian hydrocarbons in Tazhong area migrated toward structural high or stratigraphic pinch-out direction, from northwest to southeast on the plane. Therefore, trace elements of fluid inclusion can provide effective evidence for studying oil and gas migratory direction.     

Synthesis of K6Ta10.8O30 nanowires by molten salt technique

The synthesis of single crystalline K₆Ta_10.8O₃₀ nanowires by molten salt method was reported for the first time. X-ray diffraction results indicated that the as-prepared products were pure phase K₆Ta_10.8O₃₀. Scanning electron microscopy and transmission electron microscopy results showed that the products consisted of wire-like nanostructures with 100-300 nm in diameter and several micrometers in length. High resolution electron microscopy and selected area electron diffraction results indicated that the K₆Ta_10.8O₃₀ nanowires were single crystalline with a growth direction of [0 0 1]. The ultraviolet-visible diffuse reflectance measurement showed that the band gap of the nanowires was about 4.1 eV. The effects of reaction temperature, time, and weight ratio of the precursor (mixture of K₂CO₃ and Ta₂O₅) to KCl salt on the morphology of the products were investigated.     

Real options and technology management: Assessing technology migration options in wireless industry

The wireless industry is currently undergoing a major transition from second generation (2G) to third generation (3G) wireless technologies. The paper attempts to assess wireless technology migration options using the real options approach (ROA) to support the wireless network operators’ strategic decisions: to migrate or not, if so, which migration path to take. The preliminary result shows that the evolution of wireless network technologies between generations is desirable, but not within generations. Finally, from a strategic perspective, we should consider the possible challenges that may hinder migration. By identifying these challenges, we can be more watchful of transition pitfalls and can choose a better alternative.     

双加压硝酸生产中两种清除铵盐方法的比较

双加压硝酸生产中根据铵盐的数值决定铂催化剂的使用寿命和装置的安全运行。结合我公司两套双加压法（105t／a、270t／a）的运行经验，对安全条件下的经济安全运行做一些探讨。     

Characterization of vapor-induced and liquid-induced moisture migration through fractionated palm kernel (PKO) based multiphase systems

Moisture migration through PKO based films under vapor-induced and liquid-induced conditions were investigated through measurements of unsteady state diffusivity, steady state permeability, and characterization of structure. A model was developed to describe changes in diffusivity through fat-based films containing hydrophilic components. At water activity gradients of 0.80 and 0.90, there were no significant differences in diffusivity and permeability values of PKO based films containing sucrose under vapor-induced and liquid-induced conditions. Addition of sucrose decreased both diffusivity and permeability of the films at a water activity gradient of 0.80. However, at a water activity gradient of 0.90, addition of sucrose increased permeability. At a water activity gradient of 1.0, diffusivity and permeability were significantly higher in sucrose containing films at liquid-induced condition than at vapor-induced condition. Addition of sucrose at a water activity gradient of 1.0 significantly reduced diffusivity but increased permeability under both vapor-induced and liquid-induced conditions. There were no significant differences in diffusivity and permeability of the film containing lecithin or cellulose under liquid-induced and vapor-induced conditions at a water activity gradient of 1.0. Addition of lecithin or cellulose significantly reduced diffusivity but increased permeability.     

中国照相感光材料工业呈上升趋势

数字图像处理网络化和影像市场全球化加快了国内感光材料工业的数码化进程，国内照相感光材料的生产产量和市场需求量有所扩大。本文叙述了2001--2007年国内照相感光材料工业上升的经营情况，照相材料产品结构继续调整和感光材料生产厂商不断推出消费类、医疗类和印刷类新影像产品等趋势。总之，数字影像产品已经成为国内照相器材市场的主流。