榕树传粉生物学的特性

榕树传粉生物学是当今植物生殖生物学研究的一个热点.榕树为榕小蜂提供具生态保护作用的栖息场所和生长发育必须的营养物质,榕小蜂为榕树传粉,二者是植物和昆虫间高度专一化的互惠共生伙伴.榕树和榕小蜂各具独特的生物学特性,共生双方在形态结构、生理生态和生物学行为上高度特化和互适,在物候生活史链上环环衔接,构成一个十分复杂而精确的传粉生态系统.     

榕树传粉生物学的特性

榕树传粉生物学是当今植物生殖生物学研究的一个热点 .榕树为榕小蜂提供具生态保护作用的栖息场所和生长发育必须的营养物质 ,榕小蜂为榕树传粉 ,二者是植物和昆虫间高度专一化的互惠共生伙伴 .榕树和榕小蜂各具独特的生物学特性 ,共生双方在形态结构、生理生态和生物学行为上高度特化和互适 ,在物候生活史链上环环衔接 ,构成一个十分复杂而精确的传粉生态系统 .     

昆虫对榕树的适应进化

传粉榕小蜂和榕树形成了传粉昆虫与植物间互利共生的典范.除了传粉榕小蜂外,榕果内还存在多类非传粉榕小蜂以及蝇类、蛾类、甲虫类等昆虫,这些昆虫在形态和生活史等方面形成了对榕树的适应;一些种类对榕树具有种层次上的寄主专一性,存在对寄主植物的适应辐射.而那些生活在榕树其它部位的昆虫对榕树的寄主专一性则相对较低.     

虎眼万年青属植物化学成分研究

通过查阅近年来国内外百合科虎眼万年青属植物相关文献,系统总结整理了Ornithogalum saundersiae、Ornithogalum thyrsoides和Ornithogalum caudatum三种研究较多的植物的化学成分,发现该属植物主要含有皂苷类、黄酮类、三萜类、生物碱类、多糖类和挥发油类等化学成分.通过系统的总结虎眼万年青属植物化学成分研究进展,为该属植物的研究开发提供了有价值的参考.     

杠柳属植物研究进展

目的：综述萝摩科杠柳属植物化学成分及药理作用的研究进展。方法：检索有关文献进行综合分析。结果：近几年研究表明，杠柳属植物的主要化学成分为强心苷类和C21甾类化合物，其中某些成分具有显著的强心、抗癌等药理活性。结论：杠柳属植物化学成分复杂，药理活性显著，具有进一步开发利用的前景。     

榕小蜂传粉模式与花粉形态的协同演化

正花粉是有花植物的重要繁殖特征,同时也承载着植物与其传粉者协同演化过程中的直接选择压力。榕属是高等植物中最奇特的一类植物,它的花是隐头花序,榕树只允许榕小蜂类群给它传粉授精,形成有性繁殖的种子。在全球800多种榕树中,有一半是雌雄同株的,另一半是雌雄异株的;在传粉模式上,一部分榕树是主动传粉类群,其     

罗勒属植物化学成分及药理作用研究进展

罗勒属植物为1年或多年生草本植物或灌木，可作药用或观赏。其化学成分主要有萜类、黄酮类、苯丙素类等，具有良好的抗癌、抗糖尿病、抗微生物、抗炎、抗抑郁和遗忘、抗胃肠疾病、镇痛等药理作用。本文对罗勒属主要药用植物的化学成分及药理作用进行综述，旨在为罗勒属植物的深入研究及综合开发利用提供借鉴。     

夏至草、益母草及夏枯草的化学成分及药理作用研究进展

夏至草、益母草和夏枯草均为唇形科植物,功效类似,植物形态相似,有共有和特有的化学成分,包括生物碱、萜类、黄酮类、甾体类、苯乙醇苷类、挥发油、木脂素、香豆素、蒽醌等,其主要化学成分具有改善血液微循环障碍、抗炎抗氧化、心肌保护等功能.     

对云南50种有用植物化学成分的初步探索

本文采用一般的化学方法,对云南省丽江、玉溪、西双版纳等地区采集的有用植物,共计约三十一个科,五十种植物。进行了化学成分的初步探索,定性地分析了这五十种植物所含的主要化学成分。     

天南星属植物化学成分研究进展

天南星属植物天南星、异叶天南星和东北天南星为《中国药典》所收载,已有两千多年的用药历史,也是常用中药.该属植物系有毒植物,为给安全、合理用药提供依据,近年来针对该属植物进行了深入的化学成分研究,从中分离并鉴定了包括生物碱、黄酮、木脂素和萜类等主要中药药效物质.为此,对近年来的化学成分研究进展作一综述.     

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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