孟家段水库鲢、鳙鱼生长规律的研究

孟家段水库的主要养殖鱼类鲢鱼和鳙鱼的体长(L)和体重(W)的关系分别为WH=0.035 2L2.862H和WA=0.079 4L2.6912A,该库的鲢鱼体长和体重的Von Bertalanffy方程分别为:LH=75.576 5[1-e-0.1544(t 0.3982)],WH=8 482.15[1-e-01544(t 0.3982)]2.8620;鳙鱼体长和体重的Von Bertalanffy方程分别为:LA=80.961 0[1-e-0.161(t 07794)],WA=10 848.58[1-e-0161(t 0.7794)]2.6912.并根据此方程计算出其生长速度和生长加速度的方程.该库鲢、鳙的生长参数为:L∞(H)=75.576 5 cm,W∞(H)=8 482.15 g,L∞(A)=80.961 0 cm,W∞(A)=10 848.58 g,KH=-0.154 4,KA=-0.161 1;t0(H)=0.398 2,t0(A)=0.7794;生长拐点分别为2 478.14 g(0.292W∞(H)和3 107.60 g(0.286 W∞(A)).比较几个不同纬度水体同种鱼类的vov Bertalanffy方程的系数可知其生长速度较为缓慢.     

闽江口及附近海域棘头梅童鱼的生物学特征

利用2006年8月至2007年10月4个季度月的底拖网调查数据,初步分析了闽江口及附近海域底拖网渔获物中棘头梅童鱼的生物学特性.结果表明:1)棘头梅童鱼体长与体重的关系式为:W=1.228 4×10-5L3.102 3(R2=0.973 0,n=736),体长生长方程为:Lt=183.75[1-e-0.60(t+0.27)],体重生长方程为:Wt=125.90[1-e-0.60(t+0.27)]3.102 3;2)优势体长组为100~120 mm,优势体重组有两个,分别为0~5 g和25~30 g,体重生长拐点为1.62龄;3)性腺分化和性成熟时间在冬季、春季,摄食强度在春季、夏季较强.     

南岭6种鱼类的形态比较与北江光唇鱼生长的初步研究

通过对广东南岭鱼类进行常规测量,得出了广东南岭鱼体长和体重呈幂函数正相关增长,对北江光唇鱼生长规律进行分析,其Von Bertalanffy生长方程分别为:Lt=9.4343[1-e-1.1951(t-0.1032)]和Wt=21.8831[1-e-1.1951(t-0.1032)]2.8506.     

南方白甲鱼年龄和生长的研究

对华南地区的南方白甲鱼的年龄、体长、体重组成进行了研究,对其生长规律进行了分析.体长与体重的总公式是lgW=lg0.00479+3.399lgL.生长方程式Lt=43.3×(1-e-0.227(t+0.9996);Wt=1557.085(1-e-0.227(t+0.9996))3.     

福建九龙江口凤鲚的生物学特征

利用2010年9月至2013年8月每季度从福建九龙江口的紫泥、岛美、浮宫3个站点的定置张网和流刺网渔获物中采集的凤鲚样本,分析凤鲚的生物学特性.结果表明:1)九龙江口凤鲚体长分布范围为44~239 mm,优势体长为140~160 mm,体重分布范围为0.20~69.10 g,优势体重为0.20~20 g,体长与体重的关系式为W=1.3×10-6 L3.23(R2=0.88,P<0.01,n=927),体长生长方程为Lt =246.75[1-e-0.65(t+0.21)],体重生长方程为Wt=64.94[1-e–0.65(t+0.21)]3.23 ,由此可将凤鲚看做匀速生长的鱼类;2)凤鲚夏季洄游至九龙江产卵,性成熟以Ⅴ期为主,冬季摄食强度最强;3)凤鲚的总死亡系数、自然死亡系数和捕捞死亡系数分别为2.0、0.67和1.33.结果说明九龙江口凤鲚资源已经处于过度开发状态,需要采取合理的保护和限制捕捞措施.     

渤海南部黄鲫生长与死亡特性的研究

根据1991～1992年大面积调查资料和1984～1986年定点连续观测资料,对渤海南部黄鲫成鱼和幼鱼的生长、死亡及其与生殖、摄食的关系等进行了初步分析与研究,结果表明:渤海南部黄鲫个体体长与体重间呈幂指数增长关系,黄鲫成鱼的生长方程式为:Lt=198.7[1-e-0.596(t 0.15)];Wt=89.6[1-e-0.596(t 0.15)]2.675,幼鱼的生长与时间呈直线增长关系.在适温、适盐范围内,黄鲫的生长速度主要与生殖和摄食强度有关.黄鲫生殖后有明显的自然死亡现象,其死亡速度,1龄鱼为雌鱼大于雄鱼,2～3龄鱼且雄鱼大于雌鱼.目前,渤海南部黄鲫成鱼资源已捕捞过度,对幼鱼资源损害严重,应采取措施加以繁殖保护.     

花斑副沙鳅的年龄和生长特征

2007-2008年,从澴河中采集到620尾花斑副沙鳅标本,研究了其年龄鉴别方法和生长规律。结果表明,主鳃盖骨上面有很清晰的年轮,可用于年龄鉴别,种群的年龄分布范围为1～7龄。体长和体重呈幂函数关系,W=0．000003L301506,R^2=0．9906。Von Bertalanffy生长方程为：Lt=222．3[1-e-0.2867（t＋0.2667],Wt=146．23[1-e-0.2867（t＋0.2667）]3.0252。体重生长曲线为不对称的S型曲线,具有生长拐点,t=3.59413．5941龄。为充分利用生长规律,建议捕捞4龄以上的个体。     

鱼类生长的数学描述

描述鱼类的生长,常用 von Bertalanffy 生长方程,但它是在 W=AL~3的假设条件下提出的。本文根据 W=aL~b 这一般情况,推导出鱼类的体长生长式为L_(t)=L_∞[1-e~(-k)(t-t_0)]~(1/b-2),体重增长式为 W_(t)=W_∞[1-e~(-k)(t-t_0)]~(b/b-2),并导出了生长速度、生长加速度、相对生长率的计算公式,确认不仅体重增长曲线存在拐点,体长生长曲线也有可能存在拐点。本文以 W=aL~b 代替 W=AL~3,较之 von Bertalanffy 生长方程有更普遍的意义。本文还以绿鳍马面鲢为例,估计了各项生长参数,计算了各项生长指标,得到了较为满意的结果。     

长潭水库大眼华鳊Sinibrama macrops年龄与生长的初步研究

大眼华鳊鳞片的年轮特征是以环片断裂间隙为主要特点的封闭○型轮纹。年轮形成时间一龄为4～5月,以后各龄相对推迟。体长与鳞长关系为L=37.42R+27.27(r=O.9445),体重与体长关系为W=0.01798L~(3.0518)(r=0.9674),体长生长方程为L_t=139.8[1-e~((-0.678)(t-0.3268))],体重生长方程为W_t=56.01[1-e~((-0.678(t-0.3268))]~3,其拐点坐标位置在t=1.95、W_(1.95)=16.64g,相当于0.297W_∞。大眼华鳊与鳙鱼存在摄食竞争,生长比鳙鱼慢,为了提高水库的渔业经济效益,宜适当控制大眼华鳊的种群数量。     

高位池精养斑节对虾（Penaeus monodon）的生长规律

通过对高位池养殖的斑节对虾体长和体质量的跟踪测量,研究了其生长特性及规律,结果表明,斑节对虾体长和体质量呈幂函数关系：W=9.613×10-6L3.069,b接近于3,呈等速生长;其生长分为3个时期：快速生长期30～70日龄、稳定生长期70～110日龄、110日龄后为生长缓慢期;生长早、中期（50～90日龄）肥满度逐渐升高（1.33～1.45）,趋势显著,此后呈下降趋势（1.44～1.38）;拟合出斑节对虾的von Bertal-lanffy生长方程：Lt=141.503[1-e-0.009 8（t-0.224 5）],Wt=38.332[1-e-0.009 8（t-0.224 5）]3.069,体质量生长拐点出现在114.6 d.     

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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