实验条件下原甲藻与中肋骨条藻种间相互作用研究

微藻化感作用是一种极其复杂的生理、生态学现象,其在解释微藻藻种分布、群落结构及种群动力学方向起着关键作用。选择我国典型常见赤潮优势种原甲藻(Prorocentrum micans)与中肋骨条藻(Skeletonemacostatum)作为对象,研究实验室共培养条件下2种微藻种间相互作用关系。结果表明:两者以1×104 cells/mL的密度接种共培养时,原甲藻的生长状况几乎没有显著变化(F=0.004 48,P=0.947 96>0.05),而共培养的中肋骨条藻被原甲藻强烈抑制致死(F=5.116 63,P=0.047 21<0.05)。Lotka-Volterra双藻竞争模型分析知,共培养条件下原甲藻的种间竞争能力大于中肋骨条藻的种间竞争能力。在去藻滤液实验中,灭菌处理及未经灭菌处理的原甲藻去藻滤液对中肋骨条藻的生长都没有显著影响(P>0.05);中肋骨条藻-原甲藻共培养体系的去藻滤液经灭菌处理及未经灭菌处理培养中肋骨条藻时,中肋骨条藻的生长也没有显著变化(P>0.05)。可见,中肋骨条藻与原甲藻共培养时的种间相互作用,可以由细胞间的直接接触进行,而并不需要通过介质来完成。     

基于磷酸盐浓度和起始细胞密度的沃氏藻与塔玛亚历山大藻种间竞争研究

以分离自厦门港船舶压舱水箱及沉积底泥中的一种潜在入侵藻类-沃氏藻(Woloszynskia sp.)MMDL3013和一种常见有害赤潮藻-塔玛亚历山大藻(Alexandrium tamarense (Lebour) Balech)MMDL3041为研究对象,采用半连续培养的方法研究了不同磷酸盐浓度和藻类不同起始细胞密度两因子对这两种藻种间竞争的影响.结果表明,在磷酸盐限制条件下,沃氏藻为竞争的优势种,沃氏藻和塔玛亚历山大藻表现为资源利用性竞争;而在磷酸盐丰富的环境中种间竞争具有藻类细胞密度依赖性,起始细胞密度的不同可以影响竞争的结果.     

蒽对青岛大扁藻生长的影响

为研究多环芳烃(PAHs)蒽(anthrancene)对青岛大扁藻(Platymonas subcordiformis.(wille)Hazen)的毒害作用,以青岛大扁藻为实验材料,在实验生态条件下,蒽质量浓度设为0,10,20,40,60,100μg/L,采用生态毒理学方法研究了蒽对青岛大扁藻生长的影响,并应用对数模型计算了其EC50值。实验结果表明,多环芳烃蒽具有抑制效应,并随着蒽浓度的不断增大,青岛大扁藻的相对增长率逐渐降低,蒽对青岛大扁藻的96h-EC50值为41.27μg/L。     

大型海藻龙须菜对两种海洋赤潮藻的生长抑制效应

利用共培养系统研究了在不同光照强度、生物量条件下,大型海藻龙须菜(Gracilarialemaneiform is)及其水溶性抽提液对两种海洋赤潮藻旋链角毛藻(Chaetoceros curvisetus)和椎状斯氏藻(Scrippsiella trochoidea)的生长抑制效应.结果显示,龙须菜和两种赤潮藻间存在着营养竞争,受龙须菜的影响,两种赤潮藻的最大密度与对照组相比均有所下降,其受抑制程度随着龙须菜起始密度的增大而增强,而两种赤潮藻对龙须菜生长的影响却不显著.此外,龙须菜和两种赤潮藻之间还存在着光竞争,弱光条件更适合龙须菜的生长,强光条件下龙须菜对两种赤潮藻的抑制作用减弱.此外,龙须菜水溶性抽提液也会对两种赤潮藻的生长产生抑制.     

UV-B辐射和蒽对青岛大扁藻生长的影响

通过实验生态学的方法,研究多环芳烃(PAHs)蒽与UV-B单独对青岛大扁藻(Platymonas sub-cordiformis(while)Hazen)的毒害作用,以及两者的联合毒性效应,蒽质量浓度设为0,6.25,11.50,20.00,35.00,62.50μg/L,UV-B辐射剂量设为0,0.375,1.875,3.75,7.50J/m2.实验结果表明:对青岛大扁藻的生长,多环芳烃蒽具有抑制效应,小剂量的UV-B辐射具有刺激作用,随着剂量的增加表现出抑制作用,蒽与UV-B的联合则表现出更强的抑制作用,二者表现为协同作用.蒽对青岛大扁藻的96hEC50为11.98μg/L,在UV-B辐射(3.0J/m2)作用下的蒽对青岛大扁藻的96hEC50为10.31μg/L,UV-B辐射对青岛大扁藻的48hEC50为2.934J/m2,在蒽(33.3μg/L)作用下的UV-B辐射对青岛大扁藻的48hEC50为1.531J/m2.     

环境因子对青岛大扁藻、亚心形扁藻、微绿球藻脂肪酸组成的影响

采用梯度法、正交试验L9(34)研究盐度、温度、光照强度、光照周期和氮水平对青岛大扁藻、亚心形扁藻、微绿球藻脂肪酸组成的影响.结果指出适宜于合成n-3PUFA的培养条件分别为青岛大扁藻20 ℃、1000 lx、12∶12 (LH∶DH)、2份氮水平(2×74.8mg/lNaNO3)、盐度5;亚心形扁藻为20 ℃;微绿球藻为25 ℃、4000 lx、12∶12 (LH∶DH)及2份氮水平.如果作为生物饵料,两种扁藻提供的必需脂肪酸主要是18∶3n-3,微绿球藻主要是20∶5n-3.     

菌-藻体系中无机碳源对小球衣藻生长和聚集的影响研究

为了提高微藻生长速率、实现低成本高效收集,文章以小球衣藻(Chlamydomonas microsphaera)为研究对象,探究无机碳源对菌-藻体系中微藻生长和聚集的影响。结果表明：无机碳源能够显著提高菌-藻体系中微藻生物量,当初始菌藻数量比为15∶1时,在低碳源(37.6 mg/L)水平下,经过6 d培养后微藻生物量可达1.255×10⁶个/mL,较纯藻培养体系增加30%;当碳源质量浓度升高至188.0 mg/L时,微藻数量较纯藻培养体系增加68%,可达1.681×10⁶个/mL;菌-藻体系也有助于微藻自聚集,随着无机碳源质量浓度增加,其聚集效果变得更明显,聚集率最高可达66%,远高于纯培养体系中的27%。研究结果可为微藻综合利用研究提供参考。     

丙溴磷对二种海洋微藻的GPx活性及GSH、CAR含量的影响

实验以三角褐指藻和青岛大扁藻为材料,进行了丙溴磷农药对海洋微藻的抗氧化防御系统成份－GPx(glutatione Peroxidase)活性和GSH（glutathione),CAR(carotionid)含量的影响研究,结果表明,在丙溴磷胁迫下,微藻的GPx活性呈现下降趋势,GSH和CAR含量也一明为下降趋势,并且胁迫的时间越长,胁迫的强度越大它们下降的幅度也越大,因此微藻细胞对抗氧化防御系统的能力被消弱,从而可能导致活性氧在体内的过量产生与积累,进而对藻细胞造成更大的伤害。     

多环芳烃对2种海洋微藻的联合毒性效应研究

本以青岛大扁藻（Platymonas subcordiformis)，球等鞭金藻8701（Isochrysis galbana 8701)为试验材料，采用水生毒理联合效应指数法，比较了3种多环芳烃，蒽（anthracene)，并[a]芘（benzo [a] pyrene)及1，2－苯并蒽（1，2－benzonthracene)单剂和混剂对青岛大扁藻和球等鞭金藻8701的急性毒性和联合毒性。实验结果表明：对青岛大扁藻，胁迫72h，蒽与苯并[a]芘的联合及苯并[a]芘与1，2－苯并蒽的联合为协同作用，蒽与1，2－苯并蒽的联合及蒽，苯并[a]芘与1，2－苯并蒽的联合为拮抗作用。对球等鞭金藻8701胁迫72h，苯并[a]芘与1，2－苯并蒽的联合为协同作用，其它联合均为拮抗作用。     

不同磷浓度及脉冲方式下孔石莼与亚心形扁藻间竞争的实验研究

用1次性培养法结合Monod模型测定了大型海藻－孔石莼和海洋微藻，－亚心形扁藻磷限制下的生长动力参数，并在相同实验条件下观察2种藻类对不同磁浓度及脉冲方式的反应及竞争特征。结果显示：亚心形扁藻的种群密度随着磷脉冲的增大而增加；孔石莼在不同磷脉冲供给的培养系统中，保持基本稳定的生物量。在低磷浓度（0.16μmol/L/d)下，孔石莼成为优势种群；在磷浓度较高的情况下（0.8μmol/L/d以上），亚心形扁藻成为优势种群。亚心形扁藻为r-选择，孔石莼为K－选择。     

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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