红柱石细粉对矾土烧结性能的影响

以红柱石和矾土为主要原料,粘土为烧结剂,纸浆废液为结合剂。在1420℃×3h烧成制度下,研究了红柱石的细粉加入量对材料线变化率、耐压强度和抗震稳定性能的影响。结果表明:经1420℃×3h烧成后,红柱石分解出的针状莫来石晶体交结呈网络状,强化了材料的组织结构,改善了材料的物理性能。本试验中红柱石细粉的加入量为15%时,材料综合烧结性能最好,材料线变化率最小0.03%;耐压强度高达87.6MPa;抗震稳定性(1100℃水冷次数)32次。当红柱石细粉的加入量大于15%时,由于材料线变化率的过度增大,引起材料结构的松散,导致材料性能下降,如:材料线变化率最小0.12%;耐压强度60.5MPa;抗震稳定性(1100℃水冷次数)29次。     

封装相变材料的红柱石蜂窝陶瓷储热材料及储热装置的研究

设计了原位生成堇青石结合红柱石陶瓷的组成,采用无压烧成法研制了原位生成堇青石结合红柱石L系列复相陶瓷,探讨了提高红柱石复相陶瓷的抗热震性能的途径。研究结果表明:经1400℃烧成的L4样品(红柱石70%,滑石13%,高岭土13%,γ-氧化铝4%)的综合性能最佳,其吸水率(Wa)为10.71%,气孔率(Pa)为22.95%,体积密度(D)为2.14 g/cm3;,烧成收缩为2.98%,抗折强度(σb)为92.74 MPa。热膨胀系数为5.41×10-6/℃,30次热震实验(热震条件:1100℃~室温,风冷)的强度没有损失,反而增加了26.20%,常温导热系数为1.87 W/(m·K),比热容为0.90 k J/(kg·K),储热密度为900 k J/kg(0~1000℃)。相组成分析表明样品的晶相组成为印度石(高温堇青石),莫来石,硅线石,α-方石英,α-石英等,原位生成的堇青石晶体均匀分布在莫来石晶体之间,赋予样品较好的抗热震性能。结果显示,采用原位生成堇青石结合红柱石制备的陶瓷材料能满足太阳能高温热发电储热材料良好的抗热震性能,耐高温,高强度的要求。     

MgO细粉对Al2O3-尖晶石系浇注料性能的影响

研究了MgO细粉的加入对Al2O3-尖晶石系浇注料性能的影响.在110℃×24h烘干,1 500℃×3h烧成制度下,通过改变基质中MgO细粉的加入量,对材料物理性能和力学性能进行测试.结果表明3%～5%MgO细粉的加入能显著改善Al2O3-尖晶石系浇注料的综合烧结性能如显气孔率15%～17%;体积密度3.01～3.03 g/cm3,;耐压强度和抗折强度分别高达104～115 MPa和12.5～14.5 MPa;当MgO细粉的加入量大于5%时,由于材料线变化率和显气孔率的过度增大,引起材料结构的松散,导致材料强度的降低和抗渣性能的下降如显气孔率大于20%;体积密度小于2.90 g/cm3,;耐压强度和抗折强度则分别小于100 MPa和11MPa.     

高碳硅锰TRIP钢低应变速率下的拉伸性能

研究了 0 .6 3C 1 .75Si 1 .6 8MnTRIP钢室温低应变速率下的拉伸性能 .试验用钢的等温淬火为 :90 0℃加热 ,保温 2 0min ,34 0℃等温 2h.当应变速率由 4 .6× 1 0 -3 s-1降至 4 .6× 1 0 -6s-1时 ,高碳硅锰TRIP钢的延伸率由 1 4 %～ 1 5 %提高到 2 2 %左右 ;屈服强度由 1 0 1 5MPa提高到 1 1 98MPa;极限强度由 1 4 4 8MPa提高到 1 5 4 6MPa;拉伸试样中残留奥氏体量减少 .表明该钢在低应变速率下应变诱导相变、相变诱发塑性能够充分进行 .因此 ,该钢种特别适合于用作在岩石蠕变条件下工作的煤巷超高强度锚杆材料     

无水泥结合高铝耐火浇注料的研制

SiO2 超细粉作为结合剂,以三聚磷酸钠和金属铝粉为添加剂,研究无水泥结合耐火浇注料.实验表明,当SiO2超细粉、三聚磷酸钠、铝粉、加水量的加入量分别为7%、0.23%、0.8%、3.68%时,常温(18-20℃)抗折强度为5.13 Mpa,耐压强度为4.55 Mpa,高温(1400℃2h)抗折强度迭74.88 MPa,耐压强度为13.18 MPa,烧后线变化率为0.424%.     

石灰石对MgO质中间包干式料性能的影响

研究了石灰石对MgO质中间包干式料经110℃×2 h,1 100℃×3 h和1 500℃×3 h热处理后的常温物理性能及解体性能的影响,并借助XRD分析了1 500℃×3 h热处理后干式料中的物相组成。结果表明,随着石灰石加入量的增加,经1 500℃×3 h热处理后MgO质干式料表观密度显著降低,材料的线变化率逐渐减小;当添加细颗粒石灰石时,材料的耐压强度明显降低,材料易于解体。干式料性能的变化主要同高温热处理后材料中的物相组成变化相关。     

CVD SiC涂层的C/SiC复合材料的弯曲性能

以针刺整体毡为预制体制备C／SiC复合材料,在材料表面制备CVD SiC涂层,研究涂层试样氧化前、后的微观结构和室温弯曲性能。研究结果表明：CVD SiC涂层由球形颗粒熔聚体、裸露裂纹和附着裂纹组成,于1400℃氧化时附着裂纹发生愈合;C／SiC试样的弯曲强度为119．9MPa,涂层试样及其分别经1000,1200和1400℃连续氧化5h后,弯曲强度分别为188．5,41．0,60．7和104．5MPa;随氧化温度的升高,SiC涂层的保护作用增强是残留弯曲强度提高的根本原因：C／SiC试样、涂层试样和经1200和1400℃氧化的试样均表现为分层断裂,纤维束边缘区域炭的适度氧化弱化了纤维／热解炭界面,使氧化试样表现出明显的假塑性;经1000℃氧化的涂层试样,由于纤维束的严重氧化,表现为脆性断裂特征。     

氯氧镁水泥结合铝镁质无碳不烧砖性能的研究

采用氯氧镁水泥为结合剂制备铝镁质无碳不烧砖,研究了MgCl2·6H2O和镁砂含量对材料物理性能的影响。结果表明,氯氧镁水泥能明显提高不烧砖(110℃×24h和1600℃×3h)耐压强度;随着镁砂含量的增加,不烧砖高温下低熔相量减少,镁铝尖晶石生成量增加,材料的组织结构变疏松,常温耐压强度逐渐降低。材料中镁砂的最佳加入量为10%～12%。     

保温时间对原位生成Si3N4结合MgO-C耐火材料的性能影响

 以电熔镁砂、Si粉和鳞片石墨为主要原料,木质磺酸钙溶液(1.25g/mL)为结合剂,采用两段保温烧结工艺氮气气氛下低温段1350℃保温2h和高温段1450℃分别保温2、3和4h烧成MgO-C材料.研究了保温时间对MgO-C材料物相组成、显微结构形貌以及常规物理性能的影响.结果表明,当保温时间从2h增长到3h时,试样中的物相组成以及原位生成的α-Si₃N₄和SiC晶须尺寸无明显变化,随着保温时间继续增加到4h,Si单质相消失,晶须尺寸出现明显增长.常规物理性能方面,随着保温时间的增加,试样内部CO_(g)、SiO_(g)生成量不断增加,显气孔率不断增大,体积密度和耐压强度不断下降.     

粉末铁基高温合金的制备工艺研究

采用粉末机械合金化-温压成型-真空烧结等方法制备了氧化物弥散强化铁基高温合金MA956,并对其制备工艺和组织性能进行了研究。结果表明,高能振动球磨4h粉末颗粒细小均匀,已经基本实现了合金化,将其在120℃、500MPa条件下进行温压成型,压坯密度比常温模压工艺提高了0．3g／cm3;烧结温度对烧结体组织和性能有较大的影响,粉末压坯在1350℃烧结其致密度最高,为90．8％,且显微组织致密性好。     

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.