海藻酸对水溶液中Cu2+的吸附动力学研究

制备了交联海藻酸,从静态吸附方面研究了海藻酸交联前后对Cu~(2+)的吸附性能。用三种动力学模型(准一级动力学方程,准二级动力学方程,粒子扩散方程)对不同Cu~(2+)浓度、不同吸附时间的吸附曲线进行分析,探讨了吸附剂的吸附机理。结果表明准二级动力学模型的拟合度较好,海藻酸吸附Cu~(2+)是一个复杂的非均相扩散的化学吸附过程,表面络合和吸附剂内部扩散共同控制着吸附速率。交联后吸附的平衡时间延长,吸附量增大。交联后的海藻酸是一种价格低廉,绿色环保的吸附剂。     

以正己醛为载体的乳状液膜分离尿素的研究

以正己醛为载体、以氧化环糊精为内相捕捉剂制备一种新的乳状液膜，运用其清除分离尿素，旨在研究一种治疗尿毒症或缓解症状的新型疗法．实验发现，当外相尿素溶液浓度为13g／L，载体正己醛含量为5％，内相氧化环糊精浓度为15％，内相pH=10时。乳状液膜吸附容量为24.7mg／g．内相氧化环糊精的浓度对单位吸附量起决定作用，但是对吸附速率影响不大．内相pH值由于能直接影响内相捕捉剂与尿素结合物的稳定性，所以对单位吸附量有重要影响．此种吸附剂对氨基酸吸附量仅为尿素的1／10，这为其在含大量氨基酸的人体环境中有效清除尿素提供了优良的选择性，避免了其他尿毒症吸附剂普遍存在的吸附选择性低的缺点．     

酶解双醛淀粉固定化脲酶性质的研究

采用酶解双醛淀粉固定化脲酶并对其固定化脲酶性质进行了研究。结果表明,酶解双醛淀粉固定化脲酶以后,载体之间形成较大的团状。酶解双醛淀粉载体固定化脲酶量达到24.3%。对固定化脲酶的性质研究表明,酶解双醛淀粉固定化脲酶的最适pH6.0,最适温度为70℃,具有很好的储存稳定性和较高的米氏常数,固定化脲酶重复使用10次后,活力下降了约25%。以上结果表明酶解双醛淀粉能有效固定化脲酶,是一种新型高效的固定化酶载体。     

酶解双醛淀粉固定化脲酶的酶学性质

采用酶解双醛淀粉固定化脲酶,并对相应的固定化脲酶的性质进行了研究.扫描电镜分析表明,酶解双醛淀粉固定化脲酶后,载体之间形成较大的团状.研究发现:酶解双醛淀粉固定化脲酶量达到24.3%;酶解双醛淀粉固定化脲酶的最适pH值为6.0,最适作用温度为70℃;固定化脲酶具有很好的储存稳定性和较高的米氏常数,且重复使用10次后的活力仅下降约25%.说明酶解双醛淀粉能有效固定化脲酶,是一种高效的固定化酶载体.     

甲维盐@海藻酸纳米颗粒制备及缓控释性能研究

为了减少甲维盐的用量及其对环境的影响,利用溶剂扩散法制备甲维盐纳米颗粒,并通过静电作用在颗粒表面包覆海藻酸得到纳米缓释剂,利用傅里叶变换红外光谱、动态光散射和透射电镜分析工艺条件下甲维盐@海藻酸纳米颗粒的结构对甲维盐释放特征的影响。结果表明：甲维盐@海藻酸纳米颗粒的粒径D_h和ζ-电位负值随着海藻酸用量的增加而增大,但是Ca²⁺的交联作用将导致D_h和ζ-电位负值减小。甲维盐负载与海藻酸、CaCl₂浓度有关,增大海藻酸、CaCl₂的浓度有利于提高甲维盐的包封率P_EE,但减小了甲维盐在纳米颗粒中的载药率P_LE。海藻酸包覆延缓了甲维盐的释放,其释放速率主要受到活性分子与基材的相互作用的影响。Ca²⁺与海藻酸羧基的静电结合削弱了甲维盐与海藻酸的相互作用,加快了甲维盐的扩散释放,而碱性介质中海藻酸分子与甲维盐之间的相互作用因羧基解离度的增大而增强,具有较好的缓释性能。     

升清降浊方防治慢性肾功能衰竭的临床研究

目的探讨升清降浊方治疗慢性肾功能衰竭的临床疗效。方法将60例患者随机分为升清降浊方组(治疗组)和包醛氧淀粉组(对照组)各30例。治疗组予升清降浊方中药治疗,水煎服,每日1剂。对照组予包醛氧淀粉,规格5g/包,口服,5g/次,3次/d。以上各组均以30 d为1疗程,连续治疗2个疗程。观察两组患者治疗前后的营养状态(血清白蛋白、血色素及体重等)、肾功能(血清肌酐(Scr)、尿素氮(Bun)、胱抑素C、尿蛋白等)及炎症因子指标(血清C反应蛋白、IL-1、IL-6、TNFa等)的变化。结果经过2个疗程60d的治疗并进行比较,治疗组和对照组CRF患者的上述指标均有极其显著差异(P 0.01)。结论升清降浊方治疗慢性肾功能衰竭疗效显著,对炎症因子的表达均有显著差异。     

Fe_3O_4-果胶磁性微球的制备及对Cu~(2+)的吸附性能

用天然存在且吸附能力较强的果胶包覆具有磁性的四氧化三铁纳米颗粒制备一种吸附剂-Fe3O4果胶磁性微球.通过红外光谱、扫描电镜对样品进行表征,并考察吸附时间、Cu2+的质量浓度、吸附剂用量和吸附溶液的pH值对果胶磁性微球吸附溶液中Cu2+量的影响.结果表明,果胶磁性微球对铜离子的吸附主要发生在最初的1.5 h内,通过1.5 h的吸附后,吸附反应慢慢达到平衡,果胶磁性微球的平衡吸附量为72.50 mg/g.     

固定化细菌对低浓度重金属Pb2+的吸附特征及影响因素

采用固定化技术将从污水处理厂活性污泥中筛选的吸附重金属能力强的优势细菌固定， 研究其对重金属离子Pb²⁺的吸附特征及其影响因素. 结果表明, 固定化细菌对Pb²⁺的吸附是动态过程， 180 min吸附达到平衡. 随着Pb²⁺浓度的增加， 固定化细菌与吸附量呈正相关； 当吸附体系pH=6， 离子强度为0.01 mol/L时吸附量最大；环境温度对固定化细菌吸附Pb²⁺的影响包括两个阶段； 吸附率随着吸附剂质量增加呈上升趋势， 而单位质量吸附剂吸附Pb²⁺的量呈下降趋势； 共存离子Cd²⁺降低了固定化细菌对Pb²⁺的吸附量.     

游离和固定化Synechococcus sp.细胞对铬(Ⅵ)生物吸附性能的比较研究

从pH值、温度及吸附动力学等方面比较研究游离和经海藻酸固定化的微藻Synechococcus sp.细胞生物吸附剂对Cr（VI）的吸附性能. 研究结果表明： 游离细胞吸附剂在较宽的pH值（1～12）范围内稳定, 其表面电位等电点为pH=3;在等电点前（pH〈3）细胞对Cr（VI）吸附明显增强;在等电点后（pH＞3）细胞对Cr（VI）也表现出一定的吸附. 这表明Cr（VI）主要通过静电吸附到细胞上, 吸附的作用点为蛋白质表面的质子化氨基. 游离细胞经海藻酸固定化后, 其表面电位等电点移至pH=2, 但两者的吸附行为相似, 且都与在海藻酸钙上的吸附行为显著不同, 说明固定化细胞对Cr（VI）的吸附主要是游离微藻细胞的作用;Cr（VI）在游离和固定化细胞上的吸附是一个快速的过程, 在其质量浓度低于1 g/L的范围内符合Freundlich吸附等温方程, 在10～50 ℃吸附不受温度影响.     

新型固定金属离子亲和吸附剂的制备及对蛋白质的吸附研究

以β-环糊精(β-CD)键合硅胶为载体,亚氨基二乙酸(IDA)为螯合基,制备了新型固定金属离子亲和吸附剂.通过13C固体核磁、元素分析对其进行了表征.研究了吸附剂对牛血清蛋白(BSA)的吸附特性,25℃时吸附剂对BSA的最大吸附量达35 mg/g吸附剂.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

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.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-