大弹涂鱼仔,稚,幼鱼的发育阶段

探讨了大弹涂鱼仔、稚、幼鱼发育时间、个体大小及其主要特征,并研究了其生长环节和生态特性。大弹涂鱼仔鱼系属于混合性营养类型,其混合性营养期亦即孵化后2～4日龄的开口摄食期。培育期间水温27.0～32.1℃,盐度10～26‰,仔鱼前期和仔鱼后期的早中期(孵化出膜至孵化后 27日龄)生长较慢,平均日增长量为 0.186 mm;从仔鱼后期的晚期经稚鱼期到幼鱼早期(孵化后 27～42日龄)生长较快,平均日增长量为 0.887 mm。稚鱼期生长速度比仔鱼期快,为异速生长。     

褐毛鲿仔、稚、幼鱼形态特征及其生态习性的初步观察

描述了褐毛鲿仔、稚、幼鱼的主要形态特征,并对仔、稚、幼鱼各时期提出了界定标志:仔鱼前期(1～6日龄)以油球消失为界;仔鱼后期(7～24日龄)以各鳍齐全为界;稚鱼前期(25～29日龄)以枕骨棘完备为界;稚鱼后期(30～32日龄)以全身被鳞为界;33日龄后进入幼鱼早期.仔、稚鱼培育水温22～25℃,盐度25～27.褐毛鲿受精卵为球形浮性卵,以卵径(0.81～0.86 mm),油球径(0.21 mm)和枕骨棘形态的特征为区别于其它石首鱼类卵子和仔鱼的形态依据.     

半滑舌鳎的育苗效果及生物学特征的观察

在水温为21.0～23.7 ℃,盐度为33.5的条件下,用约7.8×105粒受精卵孵出仔鱼约55万尾,孵化率达70 %左右,再经过79 d的培育,培育出幼鱼2.287×105尾,成活率达到41.5 %.初孵仔鱼平均全长(3.16±0.22)mm;初孵仔鱼至孵化后3日龄为前期仔鱼,冠状幼鳍形成,大部分仔鱼已开口,逐渐建立...     

双棘黄姑鱼人工育苗技术研究

2002年5月,在集美大学水产学院水产试验场对双棘黄姑鱼人工育苗技术进行了研究。共135万粒受精卵,孵出68万尾仔鱼,孵化率50．3％．在育苗水温为25．4～29．4℃,海水盐度为26．6～30．6,饵料系列为轮虫一卤虫无节幼体一桡足类的条件下,经34d培养,育出全长14．5～24．3mm的双棘黄姑鱼幼鱼18万尾,育苗成活率达26．5％,确立了一套较完善的育苗生产工艺。     

鮸状黄姑鱼人工繁殖与育苗技术的研究

鮸状黄姑鱼人工繁殖与育苗技术的研究表明：在网箱内培育3龄以上的亲鱼经激素诱导后可在网箱内自然产卵;催产激素LHRH-A和HCG,催产率达到100％;效应时间公36—40h之内;受精卵在水泥池充气孵化,平均孵化率为85．7％。在水泥池培育仔鱼的平均成活率为52％-75％,培育稚鱼的成活率为35％-45％,培育幼鱼的成活率为11％：使用土池培育早期仔鱼,15d仔鱼,22d稚鱼和27d稚色的成活率分别为8％,19％,30％和45％。在盐度30、水温24．2℃的条件下,从受精卵到孵化出苗需要23h30min,在试验期间海水盐度为20-34,水温18—28℃,DO6．5mg/L以上,pH值为8—8．5。     

Mian状黄姑鱼人工繁殖及海水池塘育苗研究

介绍Ｍｉａｎ状黄姑鱼（Ｎｉｂｅａｍｉｉｃｈｔｈｉｏｉｄｅｓ）的催产,受精,孵化及仔,稚,幼鱼生长发育等情况。采用海水池塘培育方法进行了人工育苗研究,试验结果说明,在繁殖季节,海水温度２０．５～２１．５℃,盐度２８．３～３０．０的条件下,催产亲鱼获产率为８３．３％,受精孵化率９５．７％,利用海水池塘,投放６５万尾４日龄仔鱼,培育期间池塘水温２２．０～２５．２℃,盐度２１．５～２８．６,经一个月培育,     

海水青鳉仔稚幼鱼发育的研究

【目的】系统掌握海水青鳉Oryzias melastigma早期发育各个阶段的形态特征。【方法】对海水青鳉仔稚幼鱼的生长发育进行连续观察和研究。【结果】在水温26~28℃,盐度27‰,14h光照∶10h黑暗的条件下,海水青鳉0日龄胸鳍发达、眼球浓黑、脊索末端向上弯曲、尾鳍条出现;1日龄鳔充气,并开口摄食;3日龄卵黄吸收完毕;4日龄油球消失,进入后期仔鱼阶段;8日龄胸鳍、臀鳍条出现;10日龄背鳍出现;25日龄各鳍发育,进入稚鱼期;35日龄各个鳍条发育完善,身体布满鳞片,形态与成鱼相似,进入幼鱼期。【结论】根据卵黄囊、油球的吸收,鳍的发育以及鳞片等发育特征将海水青鳉早期发育阶段划分为仔鱼期、稚鱼期、幼鱼期。海水青鳉各鳍的发育时序为胸鳍、尾鳍、臀鳍、背鳍、腹鳍。     

■状黄姑鱼人工繁殖及海水池塘育苗研究

介绍　状黄姑鱼（Nibenmiichthioides）的催产、受精、孵化及仔、稚、幼鱼生长发育等情况。采用海水池塘培育方法进行人工育苗研究。试验结果说明：在繁殖季节,海水温度20．5～21．5℃、盐度28．3～30．0的条件下,催产亲鱼获产率为83．3％、受精卵孵化率95．7％。利用海水池塘,投放65万尾4日龄仔鱼,培育期间池塘水温22．0～25．2℃、盐度21．5～28．6。经一个月培育,共获19．1万尾幼苗,其全长为2．0～3．8cm,成活率为29．38％。     

日本黄姑鱼全人工繁育技术研究

对16尾性腺发育较好的5龄日本黄姑鱼亲鱼进行人工促熟,获自然产优质受精卵1.45×106粒,孵出仔鱼1.20×106尾,孵化率为82.8%;在水温16.8～24.6℃,盐度23.2～29.9,溶解氧5.7～7.8 mg/L的条件下,历经48 d的培育,获平均全长4.10 cm的幼鱼6.48×105尾,育苗成活率54.0%。     

青石斑鱼Epinephelus awoara仔、稚、幼鱼日龄和形态、生长发育的研究

本文根据青石斑鱼仔、稚鱼形态变化划分为前仔鱼期、后仔鱼期、稚鱼期、幼鱼期。背、腹棘的显著伸长是石斑鱼形态发育过程中的一个典型特征。背棘、腹棘长短与仔鱼全长有明显关系。背棘和腹棘比值近似1:1。仔稚鱼全长和体重两者呈幂函数相关。在整个仔、稚、幼鱼日龄生长中可分为三个阶段,第一阶段为15日龄前的仔鱼阶段,第二阶段为40日龄前的仔稚鱼阶段,第三阶段为60日龄前的稚幼鱼阶段。各生长阶段均伴随着一个危险期。导致各危险期的主要原因是(1)饵料,(2)变态,(3)自残。对策是(1)确保适时、适口饵料供应,(2)防止水质恶化和饵料营养缺乏,(3)勤分苗和充分投饵。在生长发育中,石斑鱼个体大小差异显著,导致此现象出现是因先天性和后天性二个方面造成。     

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     

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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Brief Introduction to “Journal of Jilin University( Science Edition) ”

<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has