Sb4O5Cl2阻燃助剂的制备工艺

氯氧化锑Sb4O5Cl2同卤素配合，具有优异的阻燃协效性能．与三氧化二锑、锑酸钠等相比，它还能降低彩色塑料中的色料用量，对高聚物的透明性影响较小．直接以含锑复杂矿的氯化浸出液为原料，经还原后水解，再进一步除杂，从而制得高纯度、高白度的微细Sb4O5Cl2．实验结果表明提高水解搅拌速度可显著减小产品的粒径；混合溶液A(有机酸与无机酸的混合物)对水解产物有显著的除杂效果，能提高Sb4O5Cl2的白度，细化粉末，增强产品的光稳定性；经除杂处理后的微细粉末，平均粒径为4.35μm，白度为96.6，纯度为99.85%，产物颗粒为椭球形；本工艺简便易行，生产Sb4O5Cl2的成本比生产三氧化二锑、锑酸钠的成本低，具有广阔的工业应用前景．     

以高砷精炼铋烟尘为原料制备高纯氯氧化锑

以高砷精炼铋烟尘为原料,采用盐酸浸出、锑粉还原、水解、盐酸溶解、除杂、水解工艺制备高纯氯氧化锑。盐酸浸出高砷精炼铋烟尘,当盐酸溶液与精炼铋烟尘液固比为3：1、反应时间为4 h、反应温度为80℃、盐酸用量为1.2倍理论用量时,Sb,As,Bi和Pb浸出率分别为99.50％,92.79％,95.12％和85.34％;在盐酸浸出液中加入锑粉还原后水解,当水解温度为20℃、水解时间为1 h、稀释比为10：1时,Sb3+水解率达到98.25％;水解产物经盐酸溶解后加入除杂剂,反应1 h后进行二次水解,经过滤、洗涤、烘干所得产品;产品中Sb质量分数达到75.71％,而杂质As,Pb和Bi的质量分数分别为0.081 9％,0.039 2％和0.118 7％。产品为粒度均匀的菱形颗粒,其化学式为SB4O5Cl2。     

铅碱性精炼废渣制取三氧化二锑

研究了脆硫锑铅矿精矿与铅碱性精炼废渣同时浸出制取三氧化二锑的工艺流程,得出了浸出、还原、水解、中和等过程的最优工艺条件.该工艺的技术特点是在浸出过程中,铅碱性精炼锑酸钠渣与脆硫锑铅矿精矿互作氧化剂和还原剂.实验结果表明浸出过程中Sb浸出率为94.56%,Pb入渣率为97.43%,很好地实现了Sb与Pb的分离;浸出液经还原后,冲稀水解率达99.55%;经碱液中和,得到的三氧化二锑颜色呈白色,且其化学成分平均含量中,Sb2 O3为97.69%,As为0.0055%,Pb为0.0034%,As和Pb含量低,在用等离子体法制取超细氧化锑时可作为原料.该工艺具有综合利用程度高、环境污染小、易于实现工业化生产等优点,对于铅碱性精炼废渣的资源化利用,消除因其堆存造成的环境污染,具有十分重要的意义.     

氯氧化锑与三氧化二锑的阻燃应用性能

氯氧化锑(SbOCl,Sb4O5Cl2)的阻燃性能优异,为推广其工业应用,研究了氯氧化锑在不同材料中的阻燃性能及相关性能,并与常用的Sb2O3性能进行了比较.在软质PVC,PE,PP和ABS等高聚物中,与含Cl和Br的化合物配合使用,SbOCl和Sb4O5Cl2的协同阻燃性能都优于超细Sb2O3,且SbOCl的阻燃性能最优.添加SbOCl和Sb4O5Cl2时,材料的发烟量比添加超细Sb2O3的少.研究结果表明与添加Sb2O3的PVC薄膜透光率相比,添加SbOCl的PVC薄膜透光率要高1.0～1.2倍,添加Sb4O5Cl2的要高出0.3～0.5倍;SbOCl和Sb4O5Cl2晶体的折光率分别为1.69和1.74,表明阻燃剂的折光率与高聚物的折光率越接近,其对高聚物的透光率的影响就越小;用SbOCl和Sb4O5Cl2代替超细Sb2O3后,70℃绝缘阻燃PVC电缆料制品的各项指标均符合国家标准GB8815-88,表明SbOCl和Sb4O5Cl2可以替代超细Sb2O3作为该PVC电缆料中的阻燃添加剂.     

辉锑矿直接制备焦锑酸钠

焦锑酸钠又称酸性焦锑酸钠或锑酸钠等,其组成为Na2H2Sb2O7·XH2O（X＝0~6）,Sb的质量百分数为47．1％－60．3％。焦锑酸钠在工业上主要用于高级玻璃、光学玻璃、电视机显像管玻璃和搪瓷、陶瓷制作时的消泡剂、澄清剂、增白剂以及阻燃剂、难燃剂;是钢材用抗酸漆的重要成分及铸件用漆的不透明填料;还用作离子交换体等。多年来,国内外生产焦锑酸钠的方法大都是采用金属Sb或Sbo。为原料,以火法氧化熔炼或湿法氧化制取。本工艺以辉锑矿直接合成焦锑酸钠,获得满意的结果。该法工艺操作易于掌握控制,无严重腐蚀,无污染物排放,产品质…     

铅锑复合渣于低温真空蒸发直接制备纳米Sb2O3

以铅锑复合渣为原料,用低温真空蒸发法直接制备纳米Sb2O3.通过XRD、激光粒度仪、SEM和白度仪分别对Sb2O3的结构、形貌、粒度和白度进行表征,探讨温度、残压、时间等对Sb的蒸发率以及Sb2O3的纯度、白度和粒度的影响.研究结果表明：在温度为893 K、残压为250 Pa和时间为2 h的条件下,纳米Sb2O3具有立方晶型,其平均颗粒粒度为72 nm,比表面积为15.5 m^2/g,白度为90.0%,纯度为98.50%.     

在油酸钠分散体系中用平炉尘制备超细Fe3O4

包头钢铁公司的平炉尘含铁量高．粒径微细，以γ-Fe2O3为主．经过提纯分级可以作为生产超细磁性材料的原料．研究了平炉尘在油酸钠分散条件下制备超细Fe3O4．结果表明．加入表面活性剂可以降低超微粒子的表面能，减少其团聚倾向．得到粒径更细且均匀的超细Fe3O4粉末．     

溶胶-凝胶法制备SnP_2O_7粉体

为简化SnP2O7的制备工艺,以SnCl4·5H2O和H3PO4为原料,用溶胶-凝胶法制备SnP2O7材料.经粒度分析粒径对凝胶与磷酸反应的影响;采用X-射线衍射和扫描电镜对SnP2O7粉末进行形貌和微观组织结构分析.结果表明,原料配比n(H3PO4): n (SnCl4)=1: 0.5,在850℃制备的SnP2O7粉末颗粒细小且颗粒尺寸较均匀,平均粒径在330nm左右.     

模拟超氧化物歧化酶二(乙二胺)配合物的合成及生物活性

以乙二胺 (en)为配体 ,合成了三种具有不同构型的模拟超氧化物歧化酶的模拟化合物 :trans-[Co(en) 2 Cl2 ]· Cl,cis-[Co(en) 2 (NO2 ) 2 ]· Cl及 cis-[Co(en) 2 (NO2 ) 2 ]2 Sb2 (C4 H4 O6 ) 2 ·2 H2 O,并对它们进行了紫外、红外谱图的表征 ,利用邻苯三酚自氧化法进行了活性检测 .活性数据IC50 及 p I50 表明配合物具有抑制 O- ·2 的活性 ,cis-[Co(en) 2 (NO2 ) 2 ]2 Sb2 (C4 H4 O6 ) 2 · 2 H2 O的活性要高于其它配合物 .     

超细焦锑酸钠的制备及粒度调控

以Sb_2O_3为原料,采用配合氧化法制备超细焦锑酸钠。采用X线衍射仪(XRD)、扫描电子显微镜(SEM)和激光粒度分析对焦锑酸钠的结构、形貌和粒度进行表征,并对焦锑酸钠成分进行分析。研究搅拌速度、酒石酸(C_4H_6O_6)和氯化钠(Na Cl)用量以及浆化反应时间对焦锑酸钠粒度的影响。研究结果表明:在浆化阶段加入酒石酸将Sb_2O_3溶解生成配合物,再在碱性条件氧化可显著抑制焦锑酸钠颗粒的长大速度,颗粒粒度从39.62μm降至2.61μm,形貌由四方转变为球形颗粒。焦锑酸钠晶体生长存在沉淀-溶解动态平衡。在搅拌速度为400 r/min,物质的量比即n(C_4H_6O_6):n(Na Cl):n(Sb_2O_3)=5:12:1,浆化反应时间为120 min的条件下,可得到平均粒度为2μm左右,晶形完整的焦锑酸钠产品,锑质量分数为49.02%,纯度大于99%。     

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