中性笔出墨量与笔头结构匹配

为解决优质进口墨水与笔头匹配问题并保证中性笔的书写性能,基于有限元分析法,考虑中性墨水流变特性、笔头结构参数及加工误差等对出墨量的影响,建立中性墨水与笔头匹配的出墨量仿真模型并进行修正。结果表明,该出墨量模型的仿真结果与实际测试结果相近。该模型为中性墨水与笔头结构匹配出墨量的有效仿真提供了一种新方法,有助于提高出墨量仿真结果的准确性。     

水性香精对炭黑中性墨水的影响

考察了不同香味的水性香精对炭黑中性墨水理化性能、平均粒径、流变以及书写性能的影响,结果表明:在复杂体系的炭黑中性墨水中添加香精,要对香精进行选择,当香精的组分不含芳环化合物时,香精对墨水的性能影响较小。通过筛选香精,发现制备香型炭黑中性墨水是可行的。     

均质改性黄原胶对中性墨水分散系统影响

【目的】黄原胶优异的增稠及悬浮性能契合高端中性墨水的研发需求，但其刚性结构会导致墨水中炭黑颗粒的絮凝，不利于分散。研究了均质改性法对黄原胶体系中性墨水中炭黑颗粒分散稳定系统的影响。【方法】结合中性墨水理化性能对均质工艺进行了优化设计，并对作用机理进行了探讨。【结果】黄原胶添加量为0.15%(质量分数)的中性墨水，在50 MPa的压力下均质7次，墨水粒径可达82 nm,触变值达5.04,流变性能达到最佳，热储存性大幅提高，滑度值为0.178 N,书写性能佳，符合高质量的墨水的要求。SEM显示，均质后墨水具有更高的离心稳定性。FTIR对比均质前后的样品，发现均质后的样品在952 cm^-1处发生41 cm^-1的红移现象，说明改性增强了黄原胶分子间与分子内氢键作用力，结合试验结果与表征分析，推测氢键作用力是由黄原胶分子内丙酮酸、乙酰等活性基团与炭黑颗粒表面丰富的官能团吸附而成，也是提高颜料分散稳定性的关键。【结论】研究结果为高质量墨水的开发提供理论和实验依据，为均质机在墨水中的应用提供新思路。     

冷再生混合料用乳化沥青流变性能

为了准确评价乳化沥青流变特性对冷再生混合料路用性能的影响规律,从而为乳化沥青冷再生混合料性能指标的建立提供参考。采用界面流变和动态剪切流变的手段,以乳化沥青的界面扩张模量、黏性/弹性模量、相位角、黏性和弹性的转变点等流变参数为主要特征参数,考察其随频率和温度的变化情况以及对冷再生混合料性能的影响规律,并结合乳化沥青各组分的作用机理和流变模型分析,采用描述线性黏弹性流体的理想模型(即Maxwell流体模型)进行拟合计算,建立了多项流变参数与路用性能指标的构效关系,并进行乳化沥青冷再生混合料的性能评价。试验结果表明:所考察的流变性能参数与乳化沥青及冷再生混合料的性能有很好的相关性;界面扩张模量与乳化沥青的黏度和储存稳定性呈正相关性,其值越高,乳化沥青黏度越大,储存稳定性更佳;乳化沥青黏性-弹性的转变温度以及模量与冷再生混合料的强度和水稳定性呈正相关性,其值越大,乳化沥青冷再生混合料的强度越高,水稳定性更好;与经典的Maxwell流体模型相比,乳化沥青的cole-cole图(弹性模量对黏性模量作图)和G′/G″-ω图(弹性模量G′和黏性模量G″对频率ω作图)均与理论模型偏离,属于具有非单一结构松弛时间的非线性黏弹性流体。研究结果可为乳化沥青冷再生混合料的理论研究及性能指标的建立提供参考。     

表面活性剂对中性墨水稳定性的影响

研究了壬基酚聚氧乙烯醚(OP)、氟碳表面活性剂(FSO)与苯乙烯-马来酸酐树脂铵盐溶液(SMA)3种不同表面活性剂对中性墨水黏度、表面张力、粒度和书写性能的影响.考察了OP与FSO的复配效应.结果表明:添加OP与FSO复配的表面活性剂不但可以将中性墨水的表面张力调节到适当范围,而且改善了中性墨水黏度的稳定性.此外墨水中颜料炭黑颗粒粒度分布也较为均匀,墨水灌制成笔后划线书写线条饱满.     

中性墨水流变性与书写性能相关性研究

选取具有不同书写性能的中性墨水样品,用Kinexus Pro高级旋转流变仪分别测试其流变学参数——屈服应力τ、屈服应力对应的最大黏度值η及触变恢复时间t,并对墨水书写性能与流变学参数进行了统计关联,从流变学角度解释了中性墨水存在书写问题的原因。实验结果表明,中性墨水的流变性与书写性能有密切联系,具有良好书写性能的墨水,流变参数应满足:τ≤1.034Pa,η≥29.62Pa.s,t≥27.4s。     

SBS改性高黏沥青机理的多尺度表征

结合宏微观试验与分子模拟，对苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)改性高黏沥青的改性机理进行多尺度表征.对比高黏剂质量分数为5%～15.5%的高黏沥青流变性能与存储稳定性的变化趋势，基于红外光谱、凝胶色谱与扫描电镜试验，分析高黏沥青微观形貌、官能团、分子量组成的变化特征.开展分子动力学模拟，分析高黏剂与沥青组分相容性、高黏沥青体系稳定性及高黏剂在沥青中的扩散.结果表明：12%高黏沥青兼具较好的流变性能与存储稳定性；高黏沥青制备中基本无化学反应，5%高黏沥青中交联结构初步形成；轻质油提升SBS与沥青相容性，促进SBS分子在沥青中扩散与均匀分布，增强高黏沥青体系稳定性；高黏剂与芳香分的相容性最好，范德华力在高黏剂与沥青的分子相互作用中起主导作用.     

多尺度条件下高弹高黏改性沥青耐老化及存储稳定性诊断评价

为探究高性能添加剂对传统改性沥青抗老化行为的增强机制及其存储稳定性的影响特征，在掌握高弹高黏改性沥青基本物理性能参数的基础上，通过傅里叶红外光谱仪、动态剪切流变仪、荧光显微镜等多尺度测试手段，分析了不同老化状态下高弹高黏改性沥青的宏观流变力学行为及其微结构组成与形貌特征.结果表明：改性剂能够对传统改性沥青的基本物理性能有显著改善，残留针入度、软化点增量和残留延度等指标能够较好地评价沥青的耐老化性；傅里叶红外光谱中没有新出现的特征峰，表明沥青改性过程中以物理共混为主，羰基官能团指数、亚砜基官能团指数和聚合物指数能有效反映不同改性沥青的老化程度；通过动态剪切流变频率扫描试验获取的相位角、车辙老化指数及复数模量主曲线能够有效评价不同老化程度下沥青的流变力学行为；不同添加剂在传统改性沥青内部的分散、相容与交联状态存在差异，显著影响其内部的3维空间网状结构，进而导致其呈现不同的存储稳定性；以热塑性橡胶为主要成分的添加剂增强了传统改性沥青的耐老化能力及存储稳定性能.研究成果可为高性能添加剂的甄选及先进沥青基材料的生成与调控提供理论依据与技术保障.     

三元复合驱油井流入动态特征研究

在用黏弹性流体本构模型描述三元复合驱地层流体流变特性的基础上,建立了三元复合驱地层流体在地层中渗流的基本微分方程,采用有限差分法对其进行了数值求解,并用拉格朗日插值法对产能进行预测,分析了流体的流变参数对产能的影响.通过对大庆油田采油四厂5口油井的产能预测结果与实测结果进行对比分析,其相对误差在20%以内,表明用黏弹性流体本构模型来描述地层流体的流变性能较好地预测油井的产能.     

两层聚合物共挤出过程的流变模型建立与仿真研究

使用牛顿流体模型与微分黏弹模型分别对双层聚合物共挤出过程进行了流变模型建模与仿真,得到了两路熔体流动的流变趋势与二维有限元模型.模拟结果表明:共挤过程中两路熔体在交界面处保持连续稳定流动,所受剪切应力相等,最终达到流率平衡.利用微分黏弹Oldroyd-B模型分析了共挤出过程聚合物的挤出胀大效应,可知在两路熔体体积流率逐渐增加时,共挤物的挤出形态也发生了对应偏转变化.微分黏弹模型相比普通牛顿流体模型可更好地反映聚合物共挤出加工过程中熔体的流变特性.     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to