红霉素的动态溶析结晶过程

以红霉素乳酸盐为原料,研究了红霉素溶析结晶的温度、反溶剂的含量及导入方式、溶析结晶的速度、结晶时间等因素对红霉素晶体的晶型、效价和收率的影响,并在此基础上形成了红霉素制备的变温、变搅拌强度的动态控制结晶方法。结果表明:较高温度下,控制反溶剂的导入速率,在一定的过饱和度范围内起晶,然后逐渐降温养晶;期间随着起晶、晶体生长和养晶陈化不同结晶阶段的转换采用不同的搅拌强度,以控制整个结晶过程的稳定性。该方法制备的红霉素晶体为规则的长方体,体积明显增大,粒度分布集中,生物效价也有明显提高。     

改进石灰卤水法制备Mg（OH）2

采用制盐后的卤水为原料、NH3·H2O和石灰乳作为混合沉淀剂,以卤水为底液,在一定的工艺条件下制备Mg(OH)2.考察反应温度、陈化时间、卤水的浓度和石灰乳溶液的滴加速率对Mg(OH)2性能的影响,并采用扫描电镜(SEM)、X射线衍射(XRD)等分析手段对Mg(OH)2晶体结构进行表征.试验结果表明,在反应温度60 ℃、陈化时间1.5 h、卤水浓度0.8 mol/L、石灰乳溶液的滴加速率7 mL/min时,得到了过滤时间短、钙镁质量比(简称钙镁比值)低和六方片状的Mg(OH)2产品.     

间二甲基苯甲酸的结晶提纯

采用冷冻结晶和重结晶的方法从均三甲苯氧化液中提取间二甲基苯甲酸，研究了冷冻结晶温度和陈化时间对粗产品收率的影响，采用正交试验主要考察了pH值、结晶温度和陈化时间对重结晶收率、产品酸度和熔点的影响。通过极差分析得到影响产品收率的主要因素以及优化的结晶工艺，间二甲基苯甲酸的结晶收率达81．8％。     

盐湖卤水氨法制备氢氧化镁工艺探究

以青海察尔汗盐湖卤水为原料,以氨水为沉淀剂,采用直接沉淀法制备了粒径分布均匀、分散性良好的微米级球状氢氧化镁。考察了反应温度、陈化时间、氨水加入量、沉淀剂滴加速度等工艺条件对氢氧化镁结晶及产率的影响,并通过正交试验设计优化实验条件。采用SEM分析手段对产品的粒径分布、形貌等进行了表征。结果表明,当反应温度为60℃、陈化时间为150 min、氨水加入量40 mL、沉淀剂滴加速度为6 mL/min时,制备的氢氧化镁晶体粒度均匀,结构清晰,分散性好,产率较高,产品平均粒径为20μm。该工艺条件为制备微米级球状氢氧化镁晶体提供了科学依据。     

溶析结晶纯化去乙酰真菌环氧乙酯

为考察溶析结晶纯化去乙酰真菌环氧乙酯的效果,研究了不同的溶剂、反溶剂含量和导入方式对去乙酰真菌环氧乙酯结晶的影响.在静态结晶实验的基础上,通过设计正交实验L9(34)研究动态结晶过程中各因素对去乙酰真菌环氧乙酯收率和纯度的影响.结果表明:有效地控制反溶剂含量及其导入方式可以提高晶体的纯度和收率并影响晶体的形态.去乙酰真菌环氧乙酯动态结晶最佳条件:结晶温度为15℃,溶剂-反溶剂体积比(丙酮-水)为2∶3,反溶剂流加时间为3 h.     

结晶法纯化叶酸的条件优化

为优化结晶法纯化叶酸的条件,以质量分数为95.2%的叶酸为原料,通过单因素实验和正交实验2种设计方案,以纯度和收率为指标,考察叶酸纯化结晶的最佳工艺条件;采用液相色谱-质谱联用仪和核磁共振波谱仪对叶酸的结晶产物及杂质进行分析。结果表明:结晶法纯化叶酸的最佳条件是结晶温度为85℃,酸化液体积10 m L,调晶用盐酸质量分数为10%,叶酸初始质量浓度为2.33 mg/m L,盐酸滴加速度为1.0 m L/min,搅拌速度为250 r/min,p H值为0.6;纯化后的叶酸质量分数为98.2%,杂质为N-(4-氨基苯甲酰)-L-谷氨酸;利用该结晶技术对叶酸原料进行进一步分离和精制纯化,可得到更高纯度的叶酸。     

粉煤灰硫酸焙烧熟料溶出液的除铁过程研究

对粉煤灰硫酸焙烧熟料溶出液空气和双氧水两段协同除铁过程进行研究。研究结果表明:当恒定空气流速为50 m L/min和全程搅拌速率为500 r/min时,在空气氧化时间为7 h,空气氧化温度为85℃,H_2O_2的氧化时间为30 min及其氧化温度为25℃,质量分数为14%、用量为5 m L等优化条件下可使综合除铁率达99.25%,溶出液铁质量浓度可由1.185 g/L降至8.800 mg/L;除铁后获结晶硫酸铝煅烧所得Al_2O_3品位(质量分数)为98.71%。     

Na_2CO_3调控醇热法制备规则形貌Ag纳米晶

以乙二醇为溶剂、Na2S为成核剂、聚乙烯吡喏烷酮(PVP)和Na2CO3为修饰剂,采用醇热法制备不同形貌的Ag纳米晶。通过调节反应时间、Na2CO3浓度、滴加速率以及起始滴加时间等来调控Ag纳米晶的微结构。利用场发射扫描电子显微镜(FESEM)和紫外-可见光(UV-vis)吸收光谱对Ag纳米晶的形貌和尺寸以及局域表面等离子特性(LSPR)进行表征。结果表明:浓度为50μmol/L的Na2CO3,在AgNO3滴加完毕后5.5 min时以2 mL/min的速率滴加到体系中反应3 h,能够得到平均颗粒尺寸为60 nm、尺寸分布均匀的截角立方Ag纳米晶。     

THE MECHANISM AND ENHANCING METHODS OF SOLVENTING OUT CRYSTALLIZATION

溶析结晶广泛用于有机工业结晶过程,但目前溶析结晶过程普遍存在着以下问题：晶体主粒度小,变异系数高;产品过滤分离难度大,杂质含量高．针对这些问题,本文研究了溶析结晶体系的介稳区性质,并采用了如下几种强化方法：用压力溶解和静置冷却来提高过饱和度;在沉淀剂中添加表面活性剂以及采用弹性叶片摩擦和超声波刺激来提高成核速率;动静态交替育晶减少生长分散;加入促进构型转变的物质获得所需晶型的晶体;按照最佳操作程序流加沉淀剂维持恒定的结晶过饱和度等．实验证明,采用这些方法可以显著地提高溶析结晶产品的质量．     

反应结晶法制备微粉化萘普生的研究

采用反应结晶法对萘普生进行微粉化实验研究。系统考察了温度、搅拌速度、盐酸滴加速度、药物浓度和酸溶液体积用量对反应结晶颗粒的形貌和粒度的影响。实验结果表明在温度15℃,搅拌速度1500r/nim,盐酸溶液滴加速度0.5mL/min,药物浓度0.02mol/L,盐酸溶液体积10mL,可制得微粉化六边形片状萘普生药物颗粒,且产物的粒度和形貌可控。产品的XRD、IR分析表明结晶过程对产物的晶形与化学性质均不产生影响。     

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.     

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.     

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.     

A computer generator for randomly layered structures

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

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.     

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。     

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.     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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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