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1.
本文描述了我国匙茗荷科有柄蔓足类两新记录:三齿裂楯茗荷和阿氏薄板茗荷星板亚种。所依据的标本于1980年至1982年间采集自我国东海北部海域。三齿裂楯茗荷见于三疣梭子蟹、远游梭子蟹、白斑(虫寻)、武士(虫寻)以及锦蟹的颚足或鳃腔入水孔周围体壁,阿氏薄板茗荷星板亚种大量附着于脊龙虾的鳃上。  相似文献   

2.
初始巢湖裂齿鱼(Chaohuperleidus primus)产自安徽省巢湖市马家山采石场南陵湖组上段地层(早三叠世奥伦尼克期斯帕斯亚期), 由于模式材料保存很差, 其骨骼学特征未被完整地记述。依据模式材料及同一层位发现的 3 件保存完整的新材料, 补充描述初始巢湖裂齿鱼的骨骼解剖信息, 修正其属征, 复原其头骨的骨骼模式。修正后的巢湖裂齿鱼属征支持以往的分类学结论, “顶骨与膜质翼耳骨愈合形成的骨块具有发育的前、中、后凹线, 鳃盖骨与下鳃盖骨高度近等, 下鳃盖骨具大的圆形前背突”是该属可能的近裔性状。巢湖裂齿鱼属与裂齿鱼属(Perleidus)的形态特征最相似, 除可能的近裔性状外, 与后者不同之处是次眶骨、鳃条骨和轴上鳍条的数量更多。依据巢湖裂齿鱼属头骨的骨骼特征, 与以往错误地归入裂齿鱼目的早三叠世类群及裂齿鱼目内最相近的类群进行解剖学比较和讨论, 为新鳍鱼类干群的谱系分析提供新的解剖学依据。  相似文献   

3.
研究压力喷雾荷电中两种主要荷电方法——在喷头上施加电压的直接荷电法和在喷头附近安置电晕电极的电晕荷电法的荷电机理;探讨荷电电压、雾化水压和雾化液体电导率等因素对雾滴荷质比的影响;建立了雾滴荷质比的经验公式.由试验结果和理论分析得到直接荷电法的机理是尖端效应,电晕荷电法的机理为碰撞荷电.将这两种荷电方法与感应荷电法进行了比较,指出了这三种荷电方法在消烟除尘中应用时的适用条件.  相似文献   

4.
采用有限元分析方法和多组模型试验,对考虑板中脱空和板角脱空两种情况的机场刚性道面板接缝处的应力及传荷能力进行分析。结果表明,道面板接缝处的传荷效率、道面板板底最大弯拉应力随着板底脱空面积的增大而增大。对于相同的脱空面积,接缝传荷效率和板底最大弯拉应力随着地基反应模量的增大而减小;而且板中脱空状态下的传荷效率略高于板角脱空状态下的传荷效率,板中脱空对脱空面积的反应比较敏感,这说明板中脱空对道面板产生的危害比板角脱空对道面板产生的危害要严重。  相似文献   

5.
1980年底至1982年底,作者等对我国东海杭州湾以北及嵊泗列岛一带近海的蔓足类进行了较为深入的采集,共获标本200余号.经鉴定,发现其中有一新种,兹描述如下.模式标本保存于华东师范大学生物学系. 东海裂楯茗荷Temnaspis donghaiensis sp.nov.新种.(图1~9) 正模标本C811-1,1981年11月16日采自30°15'N,125°15'E(水深约60米),附着  相似文献   

6.
我国对板鳃鱼类的研究比较薄弱.本文从演化和分类学地位、生物学研究、物种多样性和生化组分研究以及生物活性物质研究方面介绍了我国板鳃鱼类的研究进展,并对我国板鳃鱼类研究的发展方向提出几点建议.  相似文献   

7.
以三板系统模拟连续配筋水泥混凝土路面,计算获得了连续配筋路面的临界荷位.引入接缝混凝土板的传力杆设计理念,确定了连续配筋路面横向裂缝处钢筋的传荷刚度计算公式.同时,以有限元方法建立了CRCP横向裂缝处混凝土的传荷刚度计算公式.裂缝处传荷刚度的确定,为模拟CRCP荷载应力计算提供了关键参数.有限元数值计算表明:三板系统中,当边板长度大于4 m时,边界条件将不对应力计算产生影响.对于双车道路面,计算所得的板宽向最大应力位于左车道外侧车轮板底的轮迹中心处,此时的路面荷位为标准轴载位于路面右边边缘且靠近裂缝边缘,推荐此荷位作为路面承载力检验的核算位置.  相似文献   

8.
运用信息技术为主的方法对2014中国大师赛中林丹vs王睁茗比赛进行分析,对发球区域、接发技术、前场技术、中场技术、后场技术进行视频数据统计,为我国男单新秀王睁茗训练提供参考。研究指出林丹与王睁茗虽然是以发网前球为主,但是王睁茗缺少变化;王睁茗在接发球技术使用上,大量使用挑球技术,不利于自身在网前优势上的发挥;两人前场位置的战术回球都具有自身特色。王睁茗在中场防守技术上还需加强;王睁茗在杀球质量上还需要提高。  相似文献   

9.
以长白山野生茗葱Allium victorialis L.为原料,探究其不同采摘时期鳞茎和叶子中功效成分的变化规律,并找出茗葱水煮液最佳降血脂时期。采用超声波辅助提取法对茗葱中黄酮、皂苷及粗多糖进行提取并测定其质量分数,将不同采摘时期茗葱鳞茎和叶子制备成水煮液并作用于高脂饲料膳食诱导的小鼠实验组。结果显示7月下旬,茗葱鳞茎和叶子制备的水煮液对甘油三酯、总胆固醇、低密度脂蛋白胆固醇均有明显的降低作用,对高密度脂蛋白胆固醇有明显的升高作用,而在此采摘时期茗葱鳞茎中:黄酮质量分数为4.85 mg/g、皂苷质量分数为9.54 mg/g、粗多糖质量分数为56.91 mg/g;茗葱叶子中:黄酮质量分数为9.77 mg/g,皂苷质量分数为10.94 mg/g,粗多糖质量分数为34.24 mg/g。野生茗葱有良好的降血脂效果。  相似文献   

10.
海南岛水云科Ectocarpaceae藻类已报道的有7种.本文又发现7种,这7个新记录种为:(1)长囊水云Ectocarpussiliculosus(Dillw.)Lyngb;(2)矮形费氏藻Felmanniaelachistaeforma(Heydrich)comb.nov.;(3)印度费氏藻F.indica(Sonder)Womersley&Bail.;(4)混杂费氏藻。Fcommixta(Nods)comb.nov;(5)茗荷儿褐茸藻Gifferdialepasicola(Noda)comb.nov.;(6)羽状褐茸藻G.plumosa(Noda)comb.comb.nov.;(7)圣得褐茸藻G.sandriana(Zanard.)Hamel.(为新组合,并为我国首次记录)  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.
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.  相似文献   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

17.
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。  相似文献   

18.
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.  相似文献   

19.
20.
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  相似文献   

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