纳米OMMT/SBS/沥青复合材料的性能研究

采用熔融插层复合法制备了有机蒙脱土(OMMT)/苯乙烯与丁二烯的三嵌段共聚物(SBS)复合改性沥青,利用X-射线衍射仪(XRD)及光学显微镜对复合材料的微观结构进行了分析,讨论了不同质量分数的OMMT对SBS改性沥青物理性能以及对复合材料流变性能的影响,采用示差扫描量热计(DSC)对复合材料的热稳定性进行了研究,并运用离析实验对复合改性沥青的高温贮存稳定性进行了初步探讨。结果表明,OMMT的加入能有效地改善SBS的基本物理性能,提高改性沥青高温抗车辙能力、高温稳定性、耐老化性能以及贮存稳定性等。当OMMT的质量分数为3%时,复合改性沥青的综合性能最优。     

胶粉/高黏剂复合改性SBS沥青的性能与改性机理

通过添加胶粉和高黏剂对SBS改性沥青进行复合改性。采用基本物理指标研究高黏改性沥青的制备工艺;采用软化点差值法评价高黏改性沥青的热储存稳定性;采用动态剪切流变试验(DSR)研究高黏改性沥青的高温流变性能和中温抗疲劳性能;借助傅里叶红外光谱(FTIR)和差示扫描量热法(DSC)对高黏改性沥青的改性机理进行分析。基本物理试验结果表明:胶粉有助于提高改性沥青的高温性能,但对其低温性能有不利影响,高黏剂能够大幅度提高改性沥青的黏度,最佳的胶粉掺量和三种高黏剂的掺量分别为:10%、8%、7%、8%。离析试验结果表明:三种高黏改性沥青的热储存稳定性满足规范要求。DSR试验结果表明:胶粉和高黏剂有助于提高成品SBS沥青的高温性能和感温性能;短期老化后,其高温性能提高,但对感温性能产生不利影响;胶粉和高黏剂的掺入提高了沥青的中温抗疲劳性能。FTIR结果表明:胶粉和高黏剂与SBS沥青之间既存在物理共混,也有化学反应的发生。DSC结果表明:通过高黏复合改性后,沥青的高温稳定性得到有效提高。     

有机蒙脱土/废胶粉复合改性沥青的性能

采用熔融共混法制备了有机蒙脱土(OMMT)/废胶粉复合改性沥青,通过X射线衍射(XRD)分析和原子力显微镜(AFM)分析表征了复合改性沥青的微观结构,研究了复合改性沥青的物理性能、抗热氧老化性能和热储存稳定性.结果表明:OMMT的掺入使废胶粉在沥青中的分散更加均匀,OMMT/废胶粉复合改性沥青形成剥离结构;与废胶粉改性沥青相比,OMMT/废胶粉复合改性沥青的高温性能得到改善,随着OMMT掺量的增加,软化点大幅升高,25℃针入度及5℃延度减小;与废胶粉改性沥青相比,OMMT/废胶粉复合改性沥青的抗热氧老化性能和热储存稳定性明显提高.     

SBS-胶粉-HDPE复合改性沥青制备工艺

采用SK-90~#基质沥青,通过正交试验设计选择6个试验变量,制备复合改性沥青,并采用灰色关联分析法对其技术指标测试结果进行分析,得出复合改性沥青的最佳制备工艺参数.结果表明:基质沥青经过SBS-胶粉-HDPE复合改性后,针入度大幅度降低,软化点和5℃延度得到不同程度的提高,并且第22组弹性恢复率高达60%,弹性较好;通过灰色关联分析,确定制备SBS-胶粉-HDPE复合改性沥青的最佳工艺参数如下:改性剂SBS掺量为5.0%,改性剂胶粉掺量为20.0%,改性剂HDPE掺量为4.5%,剪切速率为4 500 r·min~(-1),剪切时间为45 min,剪切温度为170℃;在高温剪切的作用下,SBS和HDPE相互缠绕联结,形成以胶粉作为填充物的三维网状结构,其中聚合物作为分散介质,沥青作为分散相,从而使复合改性沥青的整体性能得到提高.     

煤直接液化残渣改性沥青低温性能的改进

为改善煤直接液化残渣(DCLR)改性沥青的低温性能,利用苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)、橡胶粉、3种增塑剂(马来酸二辛酯(DOM)、邻苯二甲酸二辛酯(DOP)和水性丙烯酸树脂(WAR))等方法对DCLR改性沥青进行二次复合改性,并进行5℃延度、弯曲梁流变(BBR)以及电镜扫描试验。结果表明:采用SBS(掺量(质量分数)低于3%)或橡胶粉(掺量低于15%)单一改性剂可以改善DCLR改性沥青的低温性能,如果SBS或橡胶粉掺量过高,反而起不到改善作用;采用复合改性剂(SBS和橡胶粉)对DCLR改性沥青的低温性能改善效果较好,其中采用2%SBS和15%橡胶粉复合改性剂时,DCLR改性沥青的性能基本上能满足SBS改性沥青I-D的技术要求,较单一改性剂对DCLR改性沥青低温性能改善提升约1倍;3种增塑剂中WAR对DCLR改性沥青的低温改善效果最差,DOP次之,DOM最好,其中3%DOM对DCLR改性沥青二次复合改性后的性能也能满足SBS改性沥青I-D的技术要求;3%DOM对DCLR改性沥青二次复合改性的制备工艺相对于复合改性剂(2%SBS和15%橡胶粉)操作简单,推荐利用3%DOM来提高DCLR改性沥青的低温性能。     

采用测力延度评价复合改性沥青的低温性能

将煤沥青与石油沥青共混,经SBS和橡胶粉改性制得复合改性沥青.针对不同改性剂以及不同的改性剂掺量,对复合改性沥青的测力延度进行分析,评价相关的指标屈服应变能E、拉断功W、韧性比R和柔量D5℃/F2对复合改性沥青低温性能的影响.结果表明,SBS复合改性沥青中,随着SBS含量的增大,其低温抗变形能力增强;在4％的SBS改性沥青中加入一定量的胶粉,其低温延度减小.     

苯乙烯-丁二烯-苯乙烯嵌段共聚物-改性胶粉复合改性沥青路用性能流变学分析

为研究改性剂掺量对苯乙烯-丁二烯-苯乙烯嵌段共聚物(styrene-butadiene-styrene block copolymer,SBS)-改性胶粉(modified rubber powder,MCR)复合改性沥青路用性能的影响,通过常规流变学试验方法,定性对比研究了SBS和MCR改性剂掺量对SBS-MCR复合改性沥青黏弹性的影响,量化分析了沥青胶结料路用性能的变化规律;通过多重应力蠕变试验,对比研究了不同改性剂掺量下沥青胶结料高温抗车辙性能的提升效果和差异;基于低温弯曲蠕变试验对8种沥青胶结料的蠕变劲度模量和蠕变速率进行对比研究,分析比较了材料在低温柔性和应力松弛性方面的差异.结果表明:不同改性剂掺量的SBS-MCR复合改性沥青虽然高温PG分级相同,但其抵抗高温变形的能力却可能存在差异;SBS和MCR改性剂对沥青胶结料劲度模量的提升效果相近;8种SBS-MCR复合改性沥青胶结料低温等级为-24℃,低温路用性能良好;最终推荐改性剂的合理掺量为4％SBS+11％MCR.     

废机油对改性沥青感温性及路用性能的影响

为分析废机油的掺入对苯乙烯-丁二烯-苯乙烯嵌段共聚物/胶粉(SBS/CR)复合改性沥青温度敏感性的影响,采用针入度指数(PI)、针入度黏度指数(PVN)以及黏温指数(VTS),分别评价5个不同废机油掺量的复合改性沥青在中温、中高温及高温区间下的温度敏感性,同时结合高温车辙、低温小梁、浸水马歇尔及冻融劈裂试验,全面评价掺入废机油对SBS/CR复合改性沥青混合料性能的影响规律。研究结果表明:废机油掺量对复合改性沥青感温性能在不同温度区间的影响结果具有一致性,即废机油的掺入会提高改性沥青的温度敏感性,且掺量越多,温度敏感性越强。当废机油掺量超过50%时,复合改性沥青的感温性骤增,混合料的高温稳定性显著降低。为保证SBS/CR复合改性沥青及混合料的路用性能,建议废机油掺量控制在50%以内。     

DBDPE复合阻燃剂对SBS沥青性能的影响

为了研究十溴二苯乙烷(DBDPE)复合阻燃剂对SBS改性沥青性能的影响,采用极限氧指数试验、烟密度试验、针入度试验、延度试验、软化点试验、动态剪切流变试验和弯曲梁流变试验等方法,分析不同阻燃剂掺量下SBS改性沥青阻燃抑烟性能、物理性能和流变性能。研究结果表明:DBDPE复合阻燃剂对SBS改性沥青性能具有显著影响,其阻燃抑烟性能显著提高;随着DBDPE复合阻燃剂掺量的增大,SBS改性阻燃沥青极限氧指数逐渐提高,其烟密度等级逐渐降低,当阻燃剂掺量(质量分数,下同)大于8%时,其极限氧指数大于24%且烟密度等级降幅较小,阻燃抑烟性能提升有限,SBS改性阻燃沥青针入度和延度逐渐降低,软化点逐渐提高,当阻燃剂掺量小于12%时其延度大于20 cm,当阻燃剂掺量大于12%时其软化点提高的幅度较小;DBDPE复合阻燃沥青高温抗变形能力显著提高,随着阻燃剂掺量的增大,SBS改性阻燃沥青抗车辙因子、蠕变恢复率逐渐增大,但当阻燃剂掺量大于8%时其提高的幅度较小;DBDPE复合阻燃沥青低温抗裂性能逐渐降低,随着阻燃剂掺量的增大,SBS改性阻燃沥青的低温蠕变劲度模量逐渐提高,低温蠕变速率逐渐降低,但当阻燃剂掺量大于12%时二者变幅较小。综合考虑BDDPE复合阻燃剂对SBS改性沥青阻燃性能、抑烟性能及高低温流变性能的影响可知,当其掺量为8%～12%时的技术性能较好。     

废胎胶粉复合改性高黏沥青复配体系

为研究胶粉复合改性高黏沥青复配体系的显著性影响程度及机理,选择废胎胶粉种类、废胎胶粉掺量、SBS掺量、补强剂掺量、增塑剂掺量5个试验变量制备复合改性高黏沥青。设计五因素四水平正交试验,通过极差分析研究各因素对改性沥青针入度、延度、软化点、黏韧性和60 ℃动力黏度5个技术指标的影响。结果表明：补强剂掺量对针入度影响最大,增塑剂次之;胶粉掺量对60 ℃动力黏度影响最大,与补强剂协同作用于软化点;SBS掺量对延度影响最大;粘韧性无明显规律。综合考虑各因素,得出胶粉合金添加剂的较优制备方案是：选择卡车轮胎胶粉,各物料以质量分数计,废胎胶粉：SBS：补强剂：增塑剂=100:24:10:19。较优制备方案下,通过双螺杆挤出工艺制备胶粉合金高黏添加剂,且掺量为25%时,废胎胶粉复合改性高黏沥青表现出优秀的高低温性能,沥青黏度和路用性能明显提升。     

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.     

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.     

A computer generator for randomly layered structures

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

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。     

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     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.