以β-环糊精制备除虫菊酯微胶囊及应用

采用微胶囊技术将天然除虫菊酯包埋在β-环糊精的中空疏水区以解决其在自然条件下不稳定的问题.制备的微胶囊包埋率为92.15%,载药率为8.5%,粒径范围为1～17μm.结果表明微胶囊相对原药具有较好的热稳定性和缓释性能,且缓释行为符合一级动力学模型.微胶囊在4℃冰箱中储存稳定性良好,5个月后载药率下降率在20%以内.自然条件下,微胶囊相比原药制剂可以延长1～1.5倍的作用时间.制备的微胶囊对淡色库蚊、白纹伊蚊以及二化螟、蚜虫和粘虫具有较高的灭蚊灭虫活性,可在防治害虫时单独使用.     

阿霉素微胶囊的制备及表征

采用三嵌段共聚物聚乳酸-聚乙二醇-聚乳酸（PLA-PEG-PLA）为载体,阿霉素为模型药物,通过双乳化溶剂蒸发法制备出阿霉素微胶囊,考察了稳定剂和制备条件对阿霉素微胶囊的性质及阿霉素的载药率和释放速率的影响。扫描电子显微镜和激光粒度测试表明,阿霉素微胶囊呈类球形或不完全球形,粒径大小为900nm左右。阿霉素微胶囊对阿霉素的包封率为35.7％。通过体外释药实验表明,阿霉素微胶囊可持续释药10天以上。     

脲醛树脂胶粘剂制备毒死蜱微胶囊

采用工业生产的脲醛树脂胶粘剂为原料,通过原 位聚合法制备了毒死蜱微胶囊,探讨了影响微胶囊性能的主要因素。结果表明,固化剂种类 、壳芯比和反应温度对载药量和包封率的影响较为显著,反应时间和加酸速度对载药量和包 封率的影响不大。在乙酸、草酸、对甲苯磺酸3种固化剂中,草酸效果最好;随着壳芯比的 提高,收率和包封率提高,载药量略有降低;随着反应温度升高,包封率和收率明显降低, 而载药量的变化不大。反应温度较低、加酸速度较慢的微胶囊表面较平滑。经过优化后的制 备工艺为：固化剂为草酸,壳芯比为0.94,反应温度为40℃。在此条件下制得的微胶囊 ,其载药量可达67.66%,包封率为87.68%,收率为88.23%。用本方法在较低的反应温度 下制备的微胶囊的性能不低于同等条件下以尿素和甲醛为原料制备的微胶囊,表明本法是一种简便而效果较好的毒死蜱微胶囊制备方法。     

壳聚糖亚微粒稳定的Pickering乳液制备pH响应微胶囊

采用离子凝胶法制备了壳聚糖-三聚磷酸钠(CS-TPP)亚微米颗粒,并以其为稳定剂,制备了内含聚乳酸-羟基乙酸共聚物(PLGA)和布洛芬(IBU)药物的o/w型Pickering乳液;采用溶剂挥发法制备了CS-TPP亚微米颗粒包覆的载药微胶囊,并通过静电作用包覆羧甲基纤维素钠(CMC).利用SEM、光学显微镜、荧光共聚焦显微镜、红外光谱等对载药微胶囊进行了表征.以IBU为模型药物,在模拟胃液(SGF,pH=1.2)和模拟肠液(SIF,pH=6.8)中进行载药微胶囊的体外药物释放实验.结果表明:所得载药微胶囊在SIF中释放速率为其在SGF中的约12倍,表现出良好的pH响应性.     

壳聚糖/木质素磺酸钠复凝聚法制备生物农药微胶囊

研究了以壳聚糖和木质素磺酸钠为囊材,以阿维菌素为囊芯,采用复凝聚法制备微胶囊。利用正交实验对复凝聚体系形成条件进行了初步筛选,在此基础上,深入研究了影响微胶囊载药量和包封率的各种因素,获得最佳制备工艺条件为：壳聚糖cps1500、壳聚糖浓度0.5%、木质素磺酸钠浓度2%、乳化剂Tween80/Span80配比2、乳化剂用量6 mL、壳芯比6、复凝聚时间15 min、交联剂用量4 mL、交联时间1 h,所得微胶囊的载药量和包封率可达到9.6％和82％。采用FT-IR对微胶囊进行表征的结果表明,囊芯与囊壁之间无化学键合。体外释放动力学研究结果表明,壳聚糖/木质素磺酸钠复凝聚微胶囊对阿维菌素具有一定的控释作用。     

载姜黄素香蕉纤维素微晶/PLGA多孔材料的制备及性能研究

用香蕉纤维为原料,经化学脱胶后制取香蕉纤维素微晶;用溶胶-凝胶法制备多孔材料并载入姜黄素制成载药多孔材料。用FT-IR、TG-MS、DSC、BET等对载药多孔材料的性能进行分析和研究。BET结果显示,平均孔径为15.77nm;DSC结果表明,载药多孔材料的熔融温度为93℃;利用紫外测试该载姜黄素香蕉纤维素微晶/PLGA多孔材料的体外释放性能,载药量测得在10%左右,包封率在42%.对载药量等指标的研究,探讨本研究所制备的载姜黄素香蕉纤维/PLGA多孔材料的释药行为及可达到最优的条件。     

正硅酸乙酯成胶机理及铁氧体纳米复合材料合成机理

在通过溶胶-凝胶法制备CoFe2O4／SiO2纳米复合粉末过程中,正硅酸乙醇（TEOS）对制备过程中溶胶和凝胶的形成起着决定性的作用。本文首先研究了正硅酸乙确（TEOS）的成胶机理,并在此基础上得到了铰氧体纳米复合孝,料的制备工艺及其合成机理。     

负载丝裂霉素C的聚乳酸微球制备及细胞生长抑制作用研究

利用单乳化溶剂挥发法制备负载丝裂霉素C（MMC）的聚乳酸（PLA）载药微球. 优化载药微球的制备条件,当药物与载体聚合物比例为10:90时,微球的实际载药量与包封率分别达到最高值5.62%与49.1%;采用SEM对微球形貌进行表征;对载药微球的体外释药进行研究,结果表明载药微球无明显暴释现象,可有效缓释MMC达30天以上,累计释放量为84.8%;细胞实验结果表明,载药微球可以有效抑制小鼠NIH-3T3成纤维细胞的增殖.     

紫苏叶精油微胶囊的工艺优化及稳定性研究

采用单凝聚法制备了紫苏叶精油微胶囊（PO/GE）,优化了其制备工艺,考察了相关稳定性指标.采用明胶（GE）为壁材,以紫苏叶精油（Perilla Oil,PO）为芯材,以包埋率为指标,根据单因素试验结果,基于BoxBehnken中心组合设计和响应面法,建立二次多项式回归方程预测模型,得到最佳的工艺条件为：芯壁质量比为1.5∶1、单凝聚时间为63.9 min、单凝聚温度为39.1℃、反应p H值为3.6.以上优化条件制备的紫苏叶精油微胶囊形貌完整,包埋率理论值可达90.1%,常温和加温时较未包裹精油稳定性增加.     

载带姜黄素的卵磷脂/果胶锌凝胶球的性能

采用滴制法制备载带姜黄素的卵磷脂/果胶锌凝胶球,以粒径、粒质量、载药量、包封率以及体外释药性能为评价指标,讨论工艺参数对评价指标的影响.实验制备的载带姜黄素的卵磷脂/果胶锌凝胶球成球均匀,平均粒径1.34~1.59,mm,平均粒质量1.74~3.45,mg.当卵磷脂与果胶的质量比为5∶4、药胶质量比为16∶20、氯化锌质量浓度为70,g/L、果胶质量浓度40,g/L、NaOH质量浓度为30,g/L时,载药量为18.03%,包封率为85.81%,模拟小肠液中8,h累积释药率为1.64%,再进入模拟结肠环境36,h累积释药率为68.72%.结果表明,卵磷脂的加入改善了果胶锌凝胶球对姜黄素的载带效果以及缓释效果.     

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