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1.
山西省已知蜻蜓52种,文中报导35种,隶18隶,其中1属11种是省内新记录:小忽属;小忽,七条Chong,混合蜓,典足扩腹春蜓,闪绿金光伪蜻,齿背灰晴,褐肩灰蜻,异色灰蜻,来褐灰蜻,黄腿赤蜻及旭光赤蜻。  相似文献   

2.
概述云南省丰富的蜻蜓资源。研究表明:分布于云南省的蜻蜓目共计210种,分属于2亚目16科82属。列出了云南蜻蜓名录,并对其属(种)数量进行了分析。  相似文献   

3.
报道采自太原地区的蜻蜓目昆虫18种,其中5种为山西省新记录  相似文献   

4.
飞天竹蜻蜓     
竹蜻蜓是过去孩子们比较喜欢玩的自制玩具之一,它制作非常简单,玩起来又有趣,几个孩子常聚在一起玩,看谁的竹蜻蜓飞得更高。找一块竹片或者木片,裁成长15~20厘米、宽2厘米、厚3毫米左右的薄片,中间钻一个小孔,镶插一根约15厘米长的竹签作为柄,用刀具在小孔两边削出对称的斜面,一只竹蜻蜓就做好了。玩时,双手一搓,然后手一松,竹蜻蜓就会飞上天空,那一刻心中充满着成就感。  相似文献   

5.
天津地区蜻蜓研究   总被引:5,自引:0,他引:5  
依据南开大学和天津自然历史博物馆馆藏标本及近年来在天津地区17个采样点不同时期多次调查采样结果,记述天津地区蜻蜓2亚目,7科,20属,30种,其中包括天津地区1新记录科,2个新记录属和10个新记录种,初步分析区系组成,并通过数十年来蜻蜓种群的变动对该地区环境和多样性保护问题提出新的看法.  相似文献   

6.
曲阜蜻蜓的初步调查   总被引:2,自引:0,他引:2  
本文共记载23种蜻蜓,分别隶属于5科20属,其中有16种为山东省新记录。  相似文献   

7.
记载广西花坪林区蜻蜓目Odonata昆虫14种,其中4种为广西区新记录种:巨齿尾溪虫忽BayaderamelanopteryxRis、大赤蜻SympetrumbachaSylys、秋赤蜻S.depresiusculumSelys及褐顶赤蜻S.infuscatumSelys。观察标本保存于山西大学生物系和广西师范大学生物系。  相似文献   

8.
河南蜻蜓目昆虫调查   总被引:1,自引:1,他引:0  
  相似文献   

9.
10.
2020年4—10月,对安徽省黄山风景区的昆虫资源进行了系统调查.经形态学鉴定,在采集的蜻蜓标本中,福建大伪蜻(Macromia malleifera)和弯钩大伪蜻(Macromia unca)为安徽省新记录种.笔者简要描述了这2个新记录种的形态特征,并提供了雌、雄成虫的图片,为安徽省蜻蜓目昆虫资源的进一步研究提供基础资料.  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
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。  相似文献   

14.
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.  相似文献   

15.
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-  相似文献   

16.
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-  相似文献   

17.
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  相似文献   

18.
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  相似文献   

19.
<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  相似文献   

20.
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