异佛尔酮二异氰酸酯与聚乙二醇的反应动力学研究

采用~(13)C-NMR及二正丁胺滴定法研究了端羟基聚乙二醇(PEG)与异佛尔酮二异氰酸酯(IPDI)之间反应的动力学特征,发现在三苯基铋(TPB)的催化下,对[NCO]是零级反应,即反应与IPDI分子上两个-NCO基团的活性无关,当以二月桂酸二丁基锡(DBTDL)为催化剂时,对[NCO]为二级反应,而且与异佛尔酮脂环的碳原子相连的-NCO表现较强的反应能力.采用DBTDL与TPB混合催化时,反应表现为二者的加和作用,混合催化剂的应用有利于前期反应的加速和后期反应的完善,提出了不同反应条件下的反应机理。     

水性双组分聚氨酯柔感涂料的制备及性能

以自制聚酯多元醇、二异氰酸酯为原料分别合成含羟基端水性聚氨酯及水性聚氨酯,并以亲水性脂肪族聚异氰酸酯为固化剂,添加适量助剂配制水性双组分聚氨酯柔感涂料.考察了聚酯多元醇的相对分子质量、二羟基丙酸(DMPA)的用量、-OH/-NCO比例等与涂料的稳定性、铅笔硬度、附着力、柔韧性、耐水性、耐溶剂性、耐化学品性、耐刮伤性以及耐化妆品性之间的关系.研究结果发现:合成水性聚氨酯分散体所用的聚酯多元醇的相对分子质量为2 000,DMPA质量分数为6%,合成羟基端水性聚氨酯分散体中-OH/-NCO=1.6,固化过程中-NCO/-OH=1.5～1.6时,涂料的综合性能最好.     

紫外光固化水性聚氨酯-丙烯酸酯乳液性能的研究

选用异佛尔酮二异氰酸酯(IPDI)、聚酯二元醇、二羟甲基丙酸(DMPA)、甲基丙烯酸-β-羟乙酯(HEMA)等为原料,采用阴离子自乳化法制备了紫外光(UV)固化水性聚氨酯-丙烯酸酯乳液.考察了n(-NCO)/n(-OH)、DMPA及HEMA质量分数对乳液性能的影响.结果表明,n(-NCO)/n(-OH)为1.4～1.5,DMPA的质量分数为4.5%时乳液性能最好.同时,HEMA质量分数越高,乳液黏度越小.     

杏仁油对实验性高血脂大鼠肝脏中脂酶活性及脂肪含量的影响

以实验性高血脂模型大鼠为实验对象,设置3个杏仁油剂量(0.5,1,1.5 mL)组、高血脂组(HG)和对照组(CG),观察了不同剂量杏仁油对高血脂大鼠肝脏总脂解酶(LA)、肝脏脂蛋白脂酶(LPL)和肝脂酶(HL)活性以及肝脏脂肪含量的影响.结果表明,杏仁油高剂量组(HDG)和杏仁油中剂量组(HMG)大鼠肝脏中LA、LPL、HL活性均显著高于高血脂组(P<0.01或P<0.05),杏仁油低剂量组(HLG)大鼠肝脏中LA、HL活性显著高于高血脂组(P<0.05),杏仁油高、中剂量组大鼠的肝脏脂肪含量显著低于高血脂组(P<0.01).因此,杏仁油具有提高实验性高血脂大鼠肝脏脂酶活性以及预防和改善肝脏脂肪积累的作用.     

黄花烟草授粉前后雌蕊生理生化变化研究

以黄花烟草(Nicotiana rustica L.)为材料,研究其柱头和花柱在授粉前后可溶性糖、可溶性蛋白、酚类、氨基酸、脂肪含量及过氧化物酶(POD)活性的变化.结果表明:授粉后柱头和花柱中的可溶性糖含量和POD活性均降低,可溶性蛋白和脂肪含量增加,总酚含量无明显变化,柱头氨基酸含量降低,而花柱氨基酸含量增加;无论是授粉前还是授粉后,与同一时期柱头比较,花柱中的可溶性糖含量高,可溶性蛋白、酚类、氨基酸、脂肪的含量及POD活性都低.     

聚酯型水性聚氨酯的合成与性能研究

采用异佛尔酮二异氰酸酯(IPDI)与聚酯二元醇和二羟甲基丙酸(DMPA)反应制得聚酯型水性聚氨酯乳液,讨论了-NCO与-OH摩尔比值、反应温度、扩链剂种类及催化剂等对水性聚氨酯乳液及其涂膜性能的影响。研究结果表明:较好的反应条件为初始-NCO与-OH摩尔比值2.6～4.0之间,反应温度80℃。在此反应条件下,采用二月桂酸二丁基锡/三乙胺复合催化剂及二乙烯三胺/乙二胺复合扩链剂可以得到具有良好储存稳定性、耐水性和物理性能的聚酯型水性聚氨酯。     

抗菌中草药紫草的GC-MS分析

对新疆紫草(Arnebia euchroma(Royle)Johnst.)乙醇粗提物(AEC)和不同极性提取物进行抗耐药金黄色葡菌活性测试,同时采用气相色谱质谱联用方法对其95%乙醇提取物进行成分分析.紫草乙醇提取物及石油醚提取物对多种金黄色葡萄球菌耐药菌株具有较好的抑制活性,最低抑菌浓度(MIC)在4~8μg/mL和8~16μg/mL之间,乙酸乙酯提取物不具有抑菌活性.通过气相色谱-质谱联用(GC-MS)方法分析紫草提取物的主要成分,共鉴定出29个化合物,其中有4个萘醌类化合物(共计27.69%),脂肪烃和脂肪酸类物质(共计67.62%).     

1,4-二脂肪氨基-5,8-二羟基葸醌的合成及抗癌活性研究

合成抗癌药物中间体脂肪胺取代的蒽醌类化合物,并对其进行体外抗癌活性测试.以1,4,5,8-四羟基蒽醌隐色体和脂肪胺为原料,在氮气保护下进行缩合反应,然后通过氧化合成目标化合物.对目标化合物利用红外光谱和核磁共振氢谱进行表征.体外抗癌活性测试表明化合物1,4-二[2-(二甲氨基)-乙氨基]-5,8-二羟基蒽醌有较强的抗癌活性.     

活性稀释剂对环氧树脂结构和性能的影响

选用3种具有不同分子结构和官能度的缩水甘油醚——1,4-丁二醇二缩水甘油醚(BDDGE)、苯基缩水甘油醚(PGE)和癸基缩水甘油醚(DGE)作为活性稀释剂,通过黏度、DSC、热重分析和万能实验机等方法考察了其对双酚A环氧-胺固化体系的反应活性、交联网络结构和性能的影响.结果表明:芳香类稀释剂的加入,对环氧-胺固化体系的反应活性影响不大甚至有所提升,且固化物的强度和模量提高,韧性降低;而脂肪族稀释剂则明显降低了固化体系的反应活性,随着脂肪链长度的增加,固化物的强度和模量下降,韧性提高;3种稀释剂的加入均降低了环氧体系的耐热性能.     

大口黑鲈不同生长阶段肝脏脂肪沉积及脂肪代谢酶活性研究

【目的】考察大口黑鲈（Micropterus salmoides）不同生长阶段肝脏的脂肪沉积情况及脂肪代谢酶的活性。【方法】分别采集150，180，210，270，300，360，420，450和480日龄共9个生长时期的实验鱼，测定形态学指标和肝脏的粗脂肪含量及脂肪代谢关键酶的活性。【结果】随着生长时期的延长，体质量、体长逐渐增加；肥满度在450日龄最大；脏体比在150日龄最高，450日龄最低；肝体比整体呈现出缓慢降低的趋势；肝脂肪在150~210日龄积累较为严重，肝脂肪含量在生长中后期呈现出下降升高交替出现的趋势。脂蛋白脂酶活性在生长中期（360~420日龄）达到峰值后逐渐降低；激素敏感性脂肪酶、蛋白激酶A和乙酰CoA羧化酶（ACC）活性在生长初期的变化趋势较一致，均呈现先下降后升高再降低的趋势。脂肪酸合成酶（FAS）活性在生长初期先升高后降低，在后期又逐步提升。在养殖中期，肝脂肪含量与ACC活性具有统计学意义上的负相关关系(p<0.05)，与FAS活性具有统计学意义上的负相关关系(p<0.01)。【结论】大口黑鲈肝脏的脂肪沉积和脂肪代谢与生长阶段密切相关，在养殖过程中应在不同的生长阶段及时做好相应的脂肪肝病预防。     

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