两种生物反应器高密度培养小球藻研究

小球藻在水产、环保、医疗和重要生命活性物质生产等众多领域的研究与应用得到不断深入,如何高效培养出高密度小球藻以满足各个应用领域的需要是亟待解决的难题。试验探索了利用生物反应器高密度异养培养小球藻的方法,利用气升式、机械搅拌式两种生物反应器对小球藻进行培养,初步比较了流加培养方式应用在两种生物反应器的效果。通过流加高浓度培养基得到细胞总数1.988×107/mL,最大细胞干重29.944g/L。结果表明,在机械搅拌式生物反应器中流加培养基能够获得最大生长量。     

红豆杉细胞在反应器中培养动力学的研究

应用气升式生物反应器及搅拌式生物反应器悬浮培养红豆杉细胞,得到细胞生长和紫杉醇合成动力学曲线.经过反应器动力学的比较,结果表明红豆杉细胞较适于在机械搅拌式反应器中培养.     

搅拌式光生物反应器培养紫球藻的条件优化

研究在光生物反应器中搅拌速度、通气量、光照强度和装液量对紫球藻生长的影响.实验结果表明:在摇床培养过程中,紫球藻的生物量和胞外多糖随着三角瓶装液量的减少而增加.通过正交试验对搅拌式光生物反应器的三个培养条件通气量、搅拌转速和光照强度进行优化,获得搅拌式光生物反应器培养紫球藻的最佳条件为通气量120L/h、搅拌转速200r/min和光照强度5000lx,在该条件下紫球藻的生物量为2.548g/L、胞外多糖557.2mg/L.正交试验分析表明,三个培养条件中通气量对藻生物量和胞外多糖含量的影响最明显.通过采用DPS软件对正交实验结果进行二次多项式模型分析和拟合,以生物量和胞外多糖为指标建立回归模型,得到相应的优化条件和预测值.     

悬浮生物载体空问结构的数值评价

为了评价及优化移动床生物膜反应器的重要材料--悬浮生物载体的空间结构,采用动网格模型与两相流模型耦合的动态数值模拟方法对装有悬浮生物载体的移动床反应器的内部流体力学特性进行分析.计算结果表明,动网格技术与两相流技术耦合的数值方法能够很详细地模拟悬浮生物载体在移动床生物反应器中的运动,以及其中每个瞬时的计算域内压力、速度、气含率等流体参数的定量分布.文中还讨论了采用气含率和载体表面剪切力两个流体力学参数来评价生物载体空间结构的可行性.     

悬浮生物载体空间结构的数值评价

悬浮生物载体是移动床生物膜反应器的重要材料,其空间结构对其性能有较大影响,为了评价及优化其结构,采用动网格模型与两相流模型耦合的动态数值模拟方法对装有悬浮生物载体的移动床反应器内部流体力学特性进行分析。计算结果表明,动网格技术与两相流技术耦合的数值方法能够很真实地模拟悬浮生物载体在移动床生物反应器中的运动,及其中每个瞬时的计算域内压力、速度、气相体积分数等流体参数的定量分布,并讨论了采用气含率和载体表面剪切力两个流体力学参数来评价生物载体空间结构性能的可行性。     

发酵罐葡萄糖流加大规模异养培养小球藻

应用流加工艺在5,50,200,800,4000L机械搅拌发酵罐中大规模异养培养小球藻,与间歇异养或光照自养相比,流加培养大大地提高了细胞密度和生产率,最高细胞质量浓度达到43.31g/L,比生长速率达到0．069h^-1,细胞生产率达到0．62g/(L.h),结果表明,利用传统的机械搅拌发酵罐大规模生产小球有良好的商业化前景。     

培养紫苏细胞的生物反应器的比较

在培养紫苏植物细胞以生产花色素的过程中，选择或设计了鼓泡式和搅拌式四种不同的生物反应器，考察了各种反应器中的培养条件，结果表明，基于花色素的生产率，鼓泡式和带螺旋桨的搅拌式反应器优于两种涡轮桨反应器，本研究为该细胞培养所用反应器的选择、设计、优化和放大，提供了一定的实验依据。     

产虾青素红发夫酵母Phaffia rhodozyma的反应器培养

利用经过优化的简单培养基在5L机械搅拌式生物反应器中对产虾青素红发夫酵母Phaffia rhodozyma进行高密度培养．培养过程分两个阶段：初始阶段以细胞生长为主,大量积累酵母细胞;当细胞浓度达到一定的水平后,在培养中后期流加尿素,促进细胞内虾青素合成,提高虾青素产量．最终得细胞干重为30．8g／L,虾青素产量为28．1mg／L（以单位体积发酵液中的虾青素质量计）,虾青素含量为923．2ug／g（以每克干细胞中的虾青素质量计）,原料对细胞的转化率为0．359．研究结果为用红发夫酵母大规模培养生产虾青素奠定了基础．     

生物反应器微载体系统大规模培养草鱼细胞及病毒

采用微载体GT-2在细胞培养生物反应器中悬浮培养草鱼细胞和草鱼出血病病毒。合适的工艺条件为:温度26℃,pH6.8～7.2(生长期),7.2～7.4(接毒后),搅拌转速40 r/min,溶氧(DO)40%空气饱和度。GT-2是一种较适合于草鱼细胞贴壁生长的微载体。细胞密度可达7.4×10~6 Cells/mL,病毒滴度可达8.00。     

釜式泰勒流反应器流动特性与传质机理研究

通过设计一种气液混合射流的方案,在搅拌釜式反应器底部加装气体分布器,生成泰勒涡流。采用数值模拟和实验相结合的方法分析反应器内涡流流动特性及传质机理。结果表明：搅拌釜式反应器内泰勒涡流随旋转雷诺数变化的演变规律与常规泰勒反应器内涡流的演变规律类似;泰勒涡流的生成在搅拌釜式反应器原有的全混流流型中构建出局部的平推流区域,降低了返混;平推流区域随着旋转雷诺数的增加而扩大,在临界旋转雷诺数工况下可使反应器气相均布性提升28%,溶氧速率提升5倍左右,有效地改善了反应器内流动状况,强化了气液间的传质效率。研究结果为突破常规泰勒流反应器反应空间小的局限、扩大生产规模提供了理论研究依据,对釜式反应器的改装具有普适性,简便易行。     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with