微乳液法制备纳米氧化锌及微乳体系相行为研究

研究了表面活性剂十六烷基三甲基溴化铵(CTAB)与助表面活性剂正丁醇微乳体系的相行为,考察了表面活性剂与助表面活性剂的质量比、油相种类、锌离子浓度对微乳液拟三元相区大小的影响,以确定适宜制备纳米氧化锌的微乳体系.研究表明,当m(CTAB)∶m(正丁醇)∶m(正辛烷)=1.2∶1∶4.4时,微乳体系具有较高的增溶水量.采用该配比,在微乳体系中制备出粒径小、尺寸分布窄的纳米氧化锌,并用扫描电镜(SEM)、粉末X射线衍射(XRD)、紫外-可见吸收光谱(UV-vis)等对纳米氧化锌的形态和晶体结构进行了表征.     

迷迭香酸自微乳的制备及口服生物利用度

本文旨在制备迷迭香酸自微乳并研究其口服生物利用度。通过溶解度考察、配伍试验与伪三元相图绘制初步筛选配方，再以油相占比(质量比)、K_m(乳化剂与助乳化剂质量比)为影响因素，粒径、Zeta电位、载药量为评价指标，进行星点设计-效应面法进一步优化配方。大鼠随机分为2组，分别灌胃给予原料药(0.5%羧甲基纤维素钠溶)、自微乳，给药剂量200 mg/kg,于0.25、0.5、0.75、1、2、4、8、12 h采血，HPLC法测定迷迭香酸血药浓度，计算主要药动学参数。结果表明，自微乳配方为：MCT(中链甘油三酯)为油相、RH40为乳化剂、PEG400为助乳化剂，油相占比14.85%,K_m为2.61。与原料药相比，自微乳t_max有效缩短(P<0.01),C_max、AUC_0～t、AUC_0～∞升高(P<0.01),相对口服生物利用度提高至1.7倍，本研究证实迷迭香酸自微乳可有效提高其口服生物利用度。     

反向微乳法制备单分散纳米二氧化硅

制备了以Span80和Tween60为混合表面活性剂的反向微乳液,研究了不同配比的Span80-Tween60混合表面活性剂对微乳液最大增溶水量的影响,利用Span80-Tween60/环己烷/水(HCl)反胶束微乳体系水解正硅酸乙酯制备出单分散性好、平均粒径15~40nm的二氧化硅粒子,探讨了水与表面活性剂的摩尔比(R)、水与正硅酸乙酯的摩尔比(H)对SiO2粒子粒径的影响.结果表明:Span80和Tween60质量比为2∶5时,微乳体系有较大的溶水能力;SiO2纳米粒子粒径随着R和H的增大而增大.     

采用S/W/O/W法制备BSA-PLG微球

以生物可降解材料PLG607为载体, 采用S/W/O/W溶剂挥发法制备牛血清白蛋白(BSA)微球, 对其性质进行表征, 并考察了处方中不同添加剂对BSA-PLG微球粒径、 包封率和体外释放的影响. 结果表明, 采用S/W/O/W法所得微球粒径为40～70 μm, 表面光滑圆整. 加入添加剂（m(羟丙基 β 环糊精) ∶m(牛血清白蛋白)=1 ∶1）后包封率可以从27.9%提高到46.3%, 加入添加剂羟丙基-β-环糊精和羟基磷灰石制备蛋白微球, 能减小突释, 提高蛋白的包封率, 改善体外释放行为, 达到均匀释放.     

响应面法优化T-2毒素脂质体处方及其抗肿瘤活性

用薄膜超声法制备T 2毒素脂质体（LP-T2）, 用高效液相色谱(HPLC)法测定包封率, 并考察测定方法的线性、 加样回收率、 精密度和重复性; 用单因素法考察有机溶剂、 磷脂种类、 m(药)∶m(脂)、 水合体积、 m(磷脂)∶m(胆固醇)对包封率的影响及响应面法优化处方; 用高压均质法对脂质体整粒, 并测定粒径分布; 用噻唑蓝(MTT)法检测T-2毒素和LP-T2对5种肿瘤细胞和正常细胞的生长抑制作用. 结果表明: LP T2最佳制备工艺为以蛋黄卵磷脂(EPC)为膜材, 薄膜超声法制备, m(药)∶m(脂)=3.5, m(磷脂)∶m(胆固醇)=3.74, 4\|羟乙基哌嗪乙磺酸（Hepes, 20 mmol/L, pH=7.4）水合, 水合体积11.8 mL, 超声10 min; 高压均质整粒后平均粒径为267 nm; LP T2可显著抑制肿瘤细胞的增殖, 活性与丝裂霉素相当, 对正常细胞的IC₅₀值（1 881.54 ng/mL）高于T 2毒素（1 427.83 ng/mL）, 即毒副作用减小; LP-T2的包封率和粒径均符合药剂标准, 具有体外抗肿瘤活性.     

大粒径单分散聚合物交联微球的制备

采用分散聚合法制备出粒径8.21μm,分散系数约为0.04,交联度约为12.6%的单分散聚合微球,考察了交联剂加入方式用量,加入时间及抗坏血酸用量等因素对合成聚合物PS微球粒径和分布的影响.实验结果表明,当单体St质量分数为28.8%～33.5%,引发剂用量m(AIBN)∶m(St)=0.03～0.06,稳定剂用量m(PVP)∶m(St)=0.5～0.8,采用交联剂DVB后滴入法,交联剂用量m(DVB)∶m(St)=0.02～0.08,在反应进行到6h后开始滴加DVB,2h滴加完,可合成出单分散性好、分散系数低、大粒径高交联的PS微球.     

鼻粘膜给药用明胶微球的制备

以明胶为原料,葡聚糖为交联剂,采用乳化化学交联固化法制备鼻粘膜给药用明胶微球。结果表明:在明胶质量浓度为0.15 g/mL,乳化剂Span 80质量浓度为0.02 g/mL,搅拌速度=800 r/min,V(液体石蜡)∶V(水)=15∶1的最优反应条件下,制备的未交联明胶微球平均粒径=47±7.6μm,葡聚糖交联明胶微球的平均粒径=38±4.2μm。     

水热法制备纳米酚醛树脂微球的研究

以间苯二酚(R)、甲醛(F)为原料,氨水为催化剂,十六烷基三甲基溴化铵(CTAB)为表面活性剂,氯化钠(Na Cl)为添加剂,在乙醇与水按照一定比例形成的混合溶剂中,采用水热法合成酚醛树脂微球。研究了反应温度、反应物质量分数、表面活性剂CTAB用量及Na Cl的加入对微球形貌和平均粒径的影响。结果表明:表面活性剂CTAB的加入不仅能有效控制粒径大小,还能使产物形貌具有球形-蠕虫状-球形的变化过程;适量中性盐Na Cl的加入能有效抑制微球间的团聚,得到单分散微球。当合成条件为水热温度T=100℃,反应物质量分数w_(单体)=2%,表面活性剂CTAB用量n_(CTAB)∶n_R=1∶3,Na Cl用量n_(NaCl)∶n_R=1∶1时,反应24 h就能得到单一分散、平均粒径为150 nm的酚醛树脂微球。     

阿苯达唑自微乳的研制及稳定性分析

以阿苯达唑为模型药物,筛选其自微乳的处方并对其自微乳进行稳定性考察.通过溶解度实验、油与乳化剂的配伍实验及伪三元相图的建立,筛选阿苯达唑自微乳的组成.采用HPLC法测定处方中药物的含量并对其稳定性进行考察.阿苯达唑自微乳的组成为阿苯达唑、油酸、辛酸/葵酸三甘油酯(GTCC)、聚氧乙烯蓖麻油(Cremopher EL)和Transcutol 的质量比为0.076∶0.1∶0.1∶0.32∶0.48;强光照射(4500lx)、高温(60℃)、低温(4℃)、高低温循环实验(40℃和4℃)结果表明,该自微乳性状、含量均无明显变化.阿苯达唑自微乳能有效改善药物的溶解度,制备方法简单可行,且稳定性良好.     

硝苯地平微乳的制备及其质量评价

硝苯地平难溶于水生物利用度低微乳作为难溶性药物的理想载体可增大难溶于水药物的溶解性。将硝苯地平制备成微乳剂型使其溶解性在一定程度上增大其生物利用度也得到了提高。根据溶解在不同表面活性剂、助表面活性剂、油相中的硝苯地平的量及伪三元相图筛选硝苯地平微乳的处方得出制备硝苯地平微乳的最佳质量配比为：乳化剂-OP/无水乙醇/油酸乙酯/水=27∶13.5∶4.5∶55。所制得的微乳淡黄色、澄清、透明、流动性良好加水稀释后在透射电镜下呈圆球形平均粒径为22.89 nm;经高速离心和留样观察发现其外观、质量及粒径未发生明显变化其稳定性良好。用该方法制得的硝苯地平微乳其溶解度相对于水中提高了700多倍且制备方法简单。     

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.