葡萄糖氧化酶发酵工艺的研究

本文通过摇瓶实验确定了自选青霉菌株Ｚ—Ｉ—Ｃ分批发酵生产葡萄糖氧化酶（ＧＯＤ）的适宜工艺条件，并在２．６立升台式发酵罐中进行了小试，监测了发酵过程中溶氧（ＤＯ）、ｐＨ、还原糖、菌体干重（ＤＣＷ）、氨基氮（ＮＨ２－Ｎ）和酶活等工艺参数的变化规律，为进一步提高ＧＯＤ的发酵产率提供了依据。     

鱼露外加酶工艺的探讨

通过对鱼露外加酸发酵及自然发酵过程中氨基态氮、挥发性盐基氨的分析，可比较出鱼露在外加酶发酵及自然发酵过程中的成分变化．以市售优质天然鱼露作对照，检测外加酶鱼露产品的氨基酸及多肽的组成，得出了外加酶发酵的意义．     

发酵制备黄腐酸的研究

对黄腐酸的发酵制备及提取工艺进行了研究,以锯末,玉米面和棉籽油为主要原料进行发酵,通过正交实验得出了从发酵产物中提取黄腐酸的最佳条件：ｗＮａＯＨ＝３。５％,６０℃,浸提１．５ｈ,然后从盐酸调ｐＨ至２．０,酸析得到黄腐酸,产率可达４６．９％,另外,利用ＫＭｎＯ４氧化降解法从碱提取液中提取黄腐酸,产率可达４６．９％。     

低功率超声波对微生物发酵的影响

超声波应用于微生物的发酵过程中，可以在细胞表面暧间造成微伤，使细胞壁局部破裂，从而改变细胞膜的通透性，使胞内物质释放或胞外物质进入细胞内，低功率时，伤口很小，容易被自身修复，不会对生物体造成损伤或死亡。低功率超声加载于微生物的发酵过程中，不仅加速细胞的生长，同时也可以促进有益次生代谢产物的产率。文章综述了低功率的超声波在微生物发酵中的应用，以及对超声波在微生物发酵过程中可能存在的作用机理进行进一步的讨论。     

金色链霉菌培养条件优化研究

金色链霉菌摇瓶培养适宜的接种量为3．2％、接种时间为25h、温度在28℃左右。4g／L的硫酸铵和0．043g／L无机磷有利于产物金霉素(CTC)合成。酵母膏的加入对CTC的合成有一定促进作用,以3g／L的效果较好。在50L发酵罐中,较低浓度的无机磷对CTC发酵有利;酵母膏的加入量以4．2g／L最佳,产物效价比酵母膏加入量为2．8g／L和5．6g／L时高3．1％和9．79／5,优化发酵过程的CTC产率提高了18％。     

降低发酵热高峰值的高产谷氨酸发酵工艺研究

在夏季高温气候时,谷氨酸发酵温度容易失控,发酵产率低,针对这一现象,研究了降低发酵热高峰值的高产谷氨酸工艺。通过采用了二次接种异步发酵方法,降低发酵过程中发酵热高峰值,使发酵温度容易控制,并提高了谷氨酸发酵产率,试验中的单罐谷氨酸产量和糖酸转化率比一次接种同步发酵分别提高了22.26%和2.70%。     

反应分离耦合制备燃料乙醇研究进展

发展燃料乙醇可以降低对化石燃料的依赖,减少由化石资源的使用所带来的环境污染。然而传统的燃料乙醇发酵生产过程中存在严重的产物抑制现象,不仅限制发酵原料的糖化,还制约燃料乙醇生产强度的提高,不利于无水乙醇制取过程的节能降耗。乙醇发酵与产物分离耦合技术是解决这一难题的有效方法。该技术可以实现高浓度底物发酵或酶转化,减轻或消除产物对生物催化剂的毒害作用,提高反应速率,获取高浓度产物;还可以简化产物分离过程、降低产物分离所产生的能耗、降低生产成本。对此,本文总结了各种乙醇发酵与产物分离耦合技术,并比较其优劣,最后展望了乙醇发酵与产物分离耦合技术的前景。     

氧载体对L-天冬酰胺酶发酵过程影响的研究

以抗癌药物L－天冬酰胺酶生产为应用背景,针对发酵过程中存在的严重耗氧问题,研究了氧载体对发酵过程的影响。通过对几种氧载体的筛选,认为正十二烷最适合该发酵过程。随后以产物L－天冬酰胺酶活性、菌体浓度以及溶氧水平为主要指标,考察了氧载体在发酵过程中的作用,实验表明,发酵基质中5％正十二烷的添加量为最佳浓度,这种氧载体的加入,明显地提高了发酵介质中的溶氧水平,改善了供氧条件,增加了菌体浓度,提高了L－天冬酰胺酶发酵水平,在优化条件下,可使发酵液最终酶活提高21％左右。     

固定化Zymomonas mobilis 10225乙醇发酵研究

运动发酵单胞菌(Zymomonas mobilis10225)为乙醇发酵菌种.在葡萄糖浓度为10%(w/V)的发酵培养基中,分别进行游离细胞,固定化细胞的乙醇发酵实验.结果表明,游离细胞乙醇发酵的产率系数为0.42,达到了理论值的82.4%,而固定化细胞乙醇发酵产率系数为0.51,达到了理论产率的100%.固定化技术对于提高运动发酵单胞菌酒精发酵表现有显著作用.     

提高黑曲霉产糖化酶活力的研究

用实验室发酵罐，发酵液的投料浓度为原发酵液增加含糖量＜２％。黑曲霉ＪＩＥＳ—１变菌糖学粉酶的活力平均达１６６０１ｍｇ·Ｐｅｒ·ｈ／ｍｌ，最高达１８１１ｍｇ·Ｐｅｒ·ｈ／ｍｌ，提高产率４１．２％。发酵周期平均为１０７．２ｈ，每小时产酶活力１３６．２ｍｇ·Ｐｅｒ·ｈ／ｍｌ。     

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