钍与四环素类抗生素的显色反应及其分析应用

在pH为7.0～8.0的弱碱性溶液中,Th(Ⅳ)与四环素(TC)、强力霉素(DOTC)、土霉素(0TC)和金霉素(CTC)结合形成浅黄色配合物,最大吸收波长分别位于388,382,388和398 nm;线性范围分别是0～10.5μg@mL-1(TC和DOTC),0～10.0μg@mL-1(0TC和CTC);摩尔吸光系数ε分别为1.90×104,1.80×104,1.72×104和1.38×104L@mol-1@cm-1.当用紫外-可见分光光度计进行双波长测量时,ε分别为3.77×104,3.34×104,3.68×104和3.09×104 L@mol-1@cm-1,线性范围与单波长法基本一致.探讨了适宜的反应条件和Th(Ⅳ)与四环素、土霉素的配合比均为12.方法用于市售四环素和土霉素药物的含量测定,结果满意.     

燕山石化公司乙烯装置66×104t/a扩能改造方案的研究与决策

燕山石化公司30×104t/a乙烯装置1994年完成第一次扩能至45×104t/a的改造后，仍存在原料灵活性差、能耗高、与同期建设的乙烯装置比规模偏小等问题。以全面提高技术水平、降低能耗、增加原料灵活性、尽可能扩大生产能力为目标，充分考虑方案的可实施性、实施时的安全性、实施后的可操作性及方案的先进性和经济性，对装置技术改造的方案进行了比选研究。经改造，实现了生产能力扩大到66×104t/a的目标，实际可达71×104t/a，装置能耗明显下降，石脑油、轻柴油、重柴油、加氢裂化尾油均可作为乙烯原料。在世界上，     

上海市九段沙湿地生态系统服务功能价值评估

参考Costanza提出的生态系统服务功能类型,对九段沙湿地生态系统服务功能价值进行初步评估。估算结果是:2002年九段沙湿地生态系统服务功能年价值为(26446.184×104)y.其中气体调节功能价值(11653.2×104)y,养分循环价值(5.849×104)y,栖息地价值(4166.7×104)y,物质产品价值(17.6×104)y,科研文化价值(10602.835×104)y。     

三峡漂浮物分布式供能系统研究

长江漂浮物是威胁三峡电站运行安全的重要问题。在对三峡漂浮物数量和特点的调查和分析基础上，提出了以漂浮物能源化利用为主线，污染物治理和资源回收为两翼的三峡漂浮物生态能源系统路线，通过利用分布式能源技术系统可以为用户侧提供更可靠、清洁的高品质能源服务。研究结果表明，充分利用三峡漂浮物进行冷热电联供，可以在实现三峡库区污染治理的同时，对三峡漂浮物进行资源化利用，分布式供能系统年处理漂浮物4.7×104～9.5×104 t，节能1.3×104～3.6×104 t标煤，投资回收期4.5～8年，具有良好的技术经济性能。     

铊的环境生态迁移与扩散

报道某含铊黄铁矿矿石和各工艺过程产物中铊的含量和分布 ,各类矿石中铊含量范围 10 .0～ 5 6 .4× 10 -6;尾砂矿中铊含量约 5 0× 10 -6;炉渣中铊含量范围 2 1.7～ 4 5 .4× 10 -6;炉灰中铊含量 30 .2～ 6 8.1× 10 -6;矿区山泉水中铊含量 0 .35～ 7.86× 10 -9;选矿水中铊含量 4 .82× 10 -9;自来水中铊含量 10～ 30× 10 -12 ;硫酸厂解析水中铊含量5 5 .2～ 4 5 0× 10 -9;炉尘冲洗水中铊含量 17.1～ 37.9× 10 -9;炉渣冲洗水中铊含量 4 .2 2× 10 -9;排放水中铊含量 9.30～ 2 1.6× 10 -9.根据这些数据 ,讨论了铊在自然环境中的迁移、转化、扩散过程和生态污染 ,提出了在含铊矿产资源利用过程中 ,必须高度重视铊的环境污染效应和后果 ,采取必要的预防污染措施 ,同时应积极开展治理技术研究 .     

紫外分光光度法测定电合成产物中的邻硝基苯甲醛

研究了用紫外分光光度法测定电合成产物中邻硝基苯甲醛的含量。摩尔吸光系数为1.05×104L·cm-1·mol1,加标回收率在95.99%以上,相对标准偏差小于0.48%,醛含量在4×105～1×104mol·L1范围内服从比耳定律。方法重现性好,灵敏度高,操作简便,能满足电解过程中邻硝基苯甲醛的在线分析。     

鮸鱼规模化繁育技术研究

通过鱼亲鱼培育、促熟催产、受精卵孵化、仔稚鱼生长变态,并成功繁育幼鱼103×104尾的生产实践,完成了鱼规模化繁育技术研究。对QZY添加剂在受精卵孵化中应用和仔鱼期鱼鳔异常胀大病作了初步探讨。     

原油降凝剂乙烯-丙烯酸甲酯共聚物的制备

乙烯-丙烯酸甲酯(EMA)是一种高效的原油降凝剂,为了推动EMA在原油输送中的应用,在低压下,以异丁醇为溶剂,通过溶液聚合法得到了平均相对分子质量0.6×104～2.0×104、MA链节含量10%～50%的高相对分子质量EMA.反应体系的压力、引发剂用量、丙烯酸甲酯的用量和反应温度对共聚物EMA的相对分子质量和分子结构组成的影响以及分子结构对降凝效果的影响进行了系统地研究.     

用溶液聚合法合成高相对分子质量的原油降凝剂

在低压下以异丁醇为溶剂,采用溶液聚合法合成了平均相对分子质量较高的原油降凝剂乙烯醋酸乙烯酯共聚物(EVA),探讨了合成条件对降凝剂EVA产量和性质的影响.实验结果表明,反应体系的压力从4 MPa增加到11 MPa时,EVA的产量从3.88 g增加到11.6 g,醋酸乙烯酯(VA)链节含量从25.2% 下降到16.34%,平均相对分子质量从0.38×104增加到1.37×104;引发剂用量从0.05 g增加到0.25 g时,EVA的产量从6.0 g增加到13.3 g,VA链节含量保持在23.5%左右不变,平均相对分子质量从0.34×104增加到1.72×104.醋酸乙烯酯用量从9.5 g增加到27.0 g时,EVA的产量从4.79 g增加到10.35 g,VA链节含量从8.81%上升到22.2%,平均相对分子质量从0.63×104增加到1.51×104;反应体系的温度从333.5 K上升到373.5 K时,EVA的产量从14.33 g下降到5.14 g,平均相对分子质量从1.39×104减小到0.53×104,EVA分子结构中VA链节含量从16.8% 上升到35.3%, 总支化度从25.0 CH3/(1?000C)升高到72.9CH3/(1?000C); 反应体系的溶剂选用良溶剂时,EVA的平均相对分子质量较低,反应体系的溶剂选用非良溶剂时,EVA的平均相对分子质量较高.当苯作为溶剂时,得到的EVA的平均相对分子质量为4?951;当异丙醇为溶剂时,EVA的平均相对分子质量为1.32×104.     

胡萝卜愈伤组织的诱导及细胞悬浮培养研究

分别以胡萝卜子叶、下胚轴和直根形成层为外植体诱导出愈伤组织,并建立细胞悬浮系.实验结果表明:胡萝卜下胚轴是诱导愈伤组织和进行细胞悬浮培养的理想外植体;诱导松散型愈伤组织的最佳激素浓度配比是1.0mg/L2,4 D+0.5mg/LKT;细胞悬浮培养细胞最佳起始密度为1.125×104个/mL～2.325×104个/50mL时,7d～9d为对数生长期;继代培养4代～5代时,可得到稳定的悬浮细胞系.     

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-