三角帆蚌碱性磷酸酶的初步研究

从三角帆蚌外套膜中,部分提纯了一种碱性磷酸酶(AKP),并对AKP的某些性质进行了初步研究。该酶作用于底物磷酸苯二钠,测定其最适pH值为10.1,最适温度为40℃,Km值为1.82×10~(-3)mol/L。分别测定了某些化学试剂对该酶的作用:Mg~(2 ),Ca~(2 )离子对AKP有不同程度的激活,尤以Mg~(2 )的作用明显;KH_2PO_4,L-Phe,L-Cys,ME(巯基乙醇),DFP(二异丙基氟磷酸)和EDTA-Na均对AKP有不同程度的抑制作用,其中L-Cys和ME抑制作用最为强烈。KH_2PO_4对AKP的作用属于竞争性抑制,而DFP属于非竞争性抑制。     

赤子爱胜蚓（Eisenia foetida）纤溶酶部分理化性质研究

以赤子爱胜蚓为材料制得蚯蚓纤溶酶，测得该酶最适温度和最适ｐＨ值分别为５５℃和９。其分子量分布范围为１．８×１０４～４．２×１０４道尔顿。在最适温度和最适ｐＨ条件下，该酶动力学参数ｋｍ和Ｖ（ｍａｘ）以分别为０．５３４５ｇ／Ｌ和１８．０７２８ｕｎｉｔ／ｍｉｎ，ＰＳＭＦ对该酶活性抑制率为７０％。     

南极产低温蛋白酶菌株Marinobacter sp.R2的发酵条件及酶学性质研究

从南极海域沉积物中筛选到一产蛋白酶的菌株R2，经细菌学形态特征鉴定及16S rDNA序列分析鉴定，该菌株属于海杆菌属(Marinobacter)．生长特性研究表明该菌株属于兼性嗜冷菌，其最适生长温度为10～15℃．R2菌株能利用多种碳源产酶，最适产酶温度为20℃．粗酶液经硫酸铵盐析、DEAE cellulose-52柱层析进行初步分离纯化后进行酶学性质的研究．该菌株所分泌蛋白酶的最适作用温度为20℃，最适pH值为9～10，对热敏感．是典型的低温碱性蛋白酶．Ca^2 、Mn^2 、Cu^2 对该蛋白酶有较为明显的激活作用，而Cd^2 、Co^2 则能抑制酶活．高浓度的变性剂、PMSF、AEBSF和EDTA都能抑制该蛋白酶，表明该酶属于丝氨酸蛋白酶，且金属离子对酶活性中心构象有关键性的影响．     

对硝基酚磷酸酶的原核表达、纯化及性质研究

克隆到脂肪芽孢杆菌Bacillus stearothermophilus中的对硝基酚磷酸酶(p-nitrophenylphosphatase，pNPPase)基因，将其编码区eDNA连接到pQE30表达载体中，在E．coli M15中经IPTG诱导得到高效表达．用Ni-NTA Superflow层析柱对表达产物进行了分离纯化，初步测定了pNPPase的酶学性质．发现它的反应最适pH是10．0，最适反应温度是55℃，热稳定性Tm值为52℃，Mg^2 、Mn^2 和Co^2 对pNPPase的活性有一定的促进作用，而Zn^2 和Ni^2 对pNPPase没有影响．纯化后其比活为120U／mg．     

海水中Co2+对中国对虾仔虾生长及体内AKP和ATPase活性的影响

在去除重金属离子的海水中添不同浓度的Co2+进行养殖实验．结果表明中国对虾(Penaeuschinensis)仔虾对Co2+最佳需要量为μg／L．低浓度的Co2+对AKP和ATPase都有激活作用,高浓度的Co2+对AKP和ATPase有抑制作用．由于AKP和ATPase活性的高低与中国对虾仔虾生长状况相一致,因此AKP和ATPase活性可作为检测水中Co2+浓度是否适合中国对虾仔虾存活和生长的指标．     

参环毛蚓肠道内源性纤维素酶的分离纯化及酶学性质分析

通过对参环毛蚓肠道组织提取液进行DEAE阴离子交换及凝胶过滤层析,获得参环毛蚓单一的内源纤维素酶的活性组分.根据AlpHaEaseFCTM软件计算出该组分分子质量约为45 ku,命名为Cx1.羧甲基纤维素钠(so-dium carboxymethylcellulose,CMC)法对Cx1进行酶学性质分析.分析结果显示:对于底物羧甲基纤维素钠,Cx1的米氏常数(Km)为0.289 mg/mL,Vmax为0.446 U.mL-1.min-1,反应最适温度为55℃,最适pH为6.0,在40~60℃、pH5.0~8.0具有较好的热稳定性和pH稳定性,其相对酶活力都能保持在55%以上.Ag+和Ba2+对Cx1起显著激活作用,K+、Zn2+、Mg2+、Ca2+、NH4+、Ni2+、Na+、Pb2+部分抑制酶活性,Cu2+离子对Cx1有完全抑制作用,而Fe2+对酶活力无明显影响.     

赤子爱胜蚓纤溶酶活性的研究

研究了赤子爱胜蚓纤溶酶活性的提高条件及酶的最适作用条件。以纤维蛋白平板法测定赤子爱胜蚓纤溶酶活性。结果表明，纤溶酶在温度(57～59)℃，pH在8.0时，酶活性较稳定。赤子爱胜蚓纤溶酶干燥粉末浸泡在氯化钠等溶液中，可提高纤溶酶活性4-5倍。     

褐色高温单孢菌PE-211产纤维素酶的酶学特性研究

对褐色高温单孢菌PE-211(Thermomomospora fuscd PE-211)形态学和生物学特征进行了研究,该菌适宜在pH8．0～10．0、55-60℃条件下生长．初步研究了该菌产生的纤维素酶(CMCase)的一些基本性质,结果表明．CMCase最适作用温度为75℃,最适作用pH为9．0,Ca^2 和Mn^2 对酶反应有促进作用,Pb^2 和Hg^2 时酶反应有抑制作用．这种酶制剂在洗涤剂工业中具有良好的应用前景．     

用PCR扩增裸甲藻和微小原甲藻rRNA基因的方法研究

以赤潮种裸甲藻(Gymnodinium sp．)和微小原甲藻(Prorocentrum minimum)为试验材料，以不同方法提取其基因组并进行纯化，然后采用PCR方法扩增其rRNA基因，包括18S，28S和ITS片断，并进行扩增条件的比较和优化，得到两种藻的最佳DNA提取条件和PCR扩增条件．裸甲藻和微小原甲藻的DNA提取宜采用改良的CTAB方法；并需对粗提取的DNA用CTAB方法进行纯化．两种藻的最适模板浓度为纯化后模板1．0～2．0μL；最适Mg^2 浓度为2．0μL(25mmol／L)；ITS引物PCB扩增的退火温度为50℃，而18S三对引物的退火温度均为55℃，28S的退火温度为54℃最为适宜。     

板栗内生真菌B_2与病原菌D_1菌株培养条件研究

以菌丝体生物量为主要指标,在25℃下以120r/min的摇床速度,通过单因素实验确定了板栗2种树栖真菌液体培养适宜的碳源、氮源、最适pH.研究表明B2的最适碳源是葡萄糖,最适氮源是酵母膏,最适pH是5.0,最适固体培养基是w(木屑)78%、w(麦麸)20%、w(石膏粉)1%、w(蔗糖)1%;病原菌D1的最适碳源是蔗糖,最适氮源是蛋白胨,最适pH是6.2,最适固体培养基为w(木屑)78%、w(麦麸)10%、w(石膏粉)1%、w(蔗粉)1%、w(豆粉)10%.     

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-