河蟹蚤状幼体对蛋白质、脂肪、复合矿物盐及维生素的适宜需求量研究

采用四因子三水平的正交实验法,研究了河蟹蚤状幼体至大眼幼体阶段对饲料中蛋白质、脂肪、矿物盐及复合维生素的适宜需求量.结果表明,影响河蟹其成活率的因素主次顺序为蛋白质>维生素>矿物盐>脂肪,其最优水平分别为蛋白质55.28 %;维生素2 %;矿物盐6 %;脂肪17.39 %.     

缩短河蟹养殖周期的技术

刚孵出的河蟹蚤状幼体在海水环境中生长发育,变成小蜘蛛大小的大眼幼体,即为蟹苗.通常大眼幼体需经过一年的培育,长到20—25克的幼蟹,再养殖一年才能养成食用蟹.现江苏省盐城市郊区水产养殖场初步试验,大眼幼体能直接养成食用蟹(体重达到100克左右),可缩短养殖周期一年,其方法介绍如下:一、幼蟹培育 由于蟹苗娇小,营游泳生活,摄食范围窄,对外界条件的应变能力差,如果将捕捞的天然蟹苗或人工繁殖的蟹苗直接放养到水体中去,成活率较低,损失较大,所以要分级培育,待其长到Ⅲ—Ⅴ幼蟹时,再移入大水面进行成蟹养殖,当年可达商品蟹规格.     

中华绒螯蟹幼蟹对饲料中维生素B6的适宜需求量

试验以酪蛋白为蛋白源,配制了维生素B₆含量分别为0,10,30,60,100,150,200和400 mg/kg的8种等氮等能的半精制饲料,在静水系统中投喂体重为(2.12±0.56) g的幼蟹10周.结果表明,饲料中不同含量的维生素B₆对中华绒螯蟹的存活率、增重率、体水分和灰分含量等均没有显著影响,但饲料中添加维生素B6能够显著提高幼蟹蛋白利用率、体粗蛋白含量和粗脂肪含量.饲料中维生素B₆含量由0~100 mg/kg升高时,蛋白利用率随之显著提高.体粗蛋白和粗脂肪含量的变化趋势与蛋白质利用率相似,其中维生素B₆添加量为100 mg/kg的处理组,幼蟹的粗蛋白和粗脂肪含量显著高于对照组和400 mg/kg维生素B₆添加组.幼蟹肝胰腺中谷草转氨酶和谷丙转氨酶的活力先随着维生素B₆添加量升高而增强,添加100 mg/kg维生素B₆的试验组,幼蟹的谷丙转氨酶活力显著高于其它各试验组.根据各处理组中华绒螯蟹对饲料蛋白的利用率和肝胰腺谷丙转氨酶活力与饲料中维生素B₆的关系,采用折线回归法计算得出中华绒螯蟹幼蟹对饲料中维生素B6的最适需求量为81.675~85.740 mg/kg饲料.     

中华绒螯蟹仔蟹必需脂肪酸营养需求研究

通过正交试验法设计含亚油酸,亚麻酸,二十碳五烯酸和二十二碳六烯酸四种必需脂肪酸三因素三水平的饲料进行试验。结果表明,中华绒螯蟹从大眼幼体到仔Ⅲ期间的成活率,体重增长率和体宽增长率均受必需脂肪酸含量及其比例的影响。在本试验中,中华绒螯蟹仔蟹对亚油酸,亚麻酸,二十碳五烯酸和二十二碳六烯酸的最适需求量（%）分别为2.79、0.95,0.28和0.53。亚油酸与亚麻酸及亚油酸与二十二碳六烯酸的最佳比例分别为2.93和5.26。就中华绒螯蟹仔蟹而言,二十碳五烯酸和二十二碳六烯酸的营养生理作用最大,其次是亚麻酸,最后为亚油酸,试验结果还表明,中华绒螯蟹由大眼幼体发育至Ⅲ期仔蟹共历经三次蜕皮,首次蜕皮不受试验饵料中必需脂肪酸含量的影响。但第二次和第三次蜕皮却却受饵料中EPA和DHA含量的显著影响。此外,试验中Ⅲ期仔蟹的体脂组成随饲料不同而发生变化。并与其所摄食饲料的脂肪酸组成相类似。     

土池河蟹大眼幼体延缓变态的初步研究

河蟹土池人工育苗期间，由于受环境因素制约较大，同一地区大眼幼体变态成幼蟹的时间比较集中，易造成购销双方不必要的经济损失。作者已就室内工厂化育苗与土池育苗相配套的方法以期解决上述矛盾提出了见解。但仅具备土池育苗设施的厂家如何解决这类矛盾，其中的某些技术环节尚需进一步探索，故笔者通过实验并根据１９９６～１９９８年的生产性试验，提出几种延迟大眼幼体变态的方法以延长苗种销售时间，供育苗厂家参考。１材料与方法１．１大眼幼体来源第５期蚤状幼体变态成为大眼幼体第一天计为大眼幼体的第１ｄ龄；用１００目筛绢做成锥…     

鱼类营养研究概述

概述了近10年来国内外重要养殖鱼类营养的研究进展。包括维持鱼类生长需要的蛋白质、必需氨基酸、碳水化合物、脂肪、必需脂肪酸、维生素和矿物质的需要情况。不同鱼种所需的适宜蛋白质含量不同，一般来说海水鱼比淡水鱼需要量多，幼体比成体需要量大；ω3脂肪酸对海水鱼类较重要，而ω6对淡水鱼类相对较重要；鱼类由于缺乏胰岛素对糖类分解能力低，因此对碳水化合物的需要量较低；维生素和矿物质不同种类对鱼体产生的影响不同，一定量的维生素和矿物质是维持鱼体生长和存活必不可少的。     

对虾幼体发育的营养需要

概要综述了近年来国内外对对虾幼体的蛋白质营养需要,不同蛋白源的营养价值,添加氨基酸的利用;必需脂肪酸营养需要,对磷脂、固醇的需要;对维生素的需求和亲虾卵巢发育期对必需脂肪酸、蛋白质、维生素的营养需要的研究结果,以及对虾幼体的消化酶和消化,益生素对幼体的营养效果和功效的研究.并对比了对虾幼体和幼虾对一些营养素的利用和代谢的差别.     

拟穴青蟹大眼幼体和第Ⅰ期仔蟹对隐蔽物的选择

采用实验生态方法,以攀附率为指标,研究了青蟹大眼幼体和第Ⅰ期仔蟹对不同材质(棉布、尼龙筛绢、PVC和竹木)、放置方式(水平或垂直)和构型(3种结构×3种规格)隐蔽物的选择性.结果表明:大眼幼体和仔蟹对各种隐蔽物材质选择差异不显著(p＞0.05),对垂直放置隐蔽物的选择性显著高于水平放置者(p＜0.01),对不同结构(草丛型、洞穴型和折角型)和不同规格(5,7和10 mm)隐蔽物选择差异均极显著(p＜0.01).其中,对草丛型、洞穴型和折角型隐蔽物的选择性依次降低,对5,7和10 mm隐蔽物的选择性也依次降低.随着规格增大,大眼幼体和仔蟹对草丛型隐蔽物的选择性下降幅度最大,对5 mm草丛型隐蔽物的攀附率为30.92%和25.9%,对10 mm草丛型的仅为0.46%和1.4%. 综上所述,在研制或使用青蟹大眼幼体和仔蟹的隐蔽物时,材质选择主要应考虑耐腐蚀、对水质无不良影响、不易钩挂幼体和仔蟹附肢等因素. 隐蔽物的结构以草丛型为佳,当其亚结构的最小空隙接近大眼幼体或仔蟹全长时,应可达到最好的使用效果.     

拟穴青蟹大眼幼体相残与资源可获得性和饥饿关系的研究

以不同幼体放养密度、饵料(卤虫无节幼体)密度以及饥饿时间条件下拟穴青蟹(Scylla paramamosain)大眼幼体的肢残率和死亡率为指标,探讨了资源可获得性以及饥饿对大眼幼体相残行为的影响,发现空间和食物的可获得性及48 h内的饥饿对大眼幼体相残所致的肢残和死亡率影响均不显著,3种条件下的相残死亡率在2.27%/d～4.68%/d之间.结果显示,在本实验条件下,资源可获得性和饥饿对大眼幼体的相残无显著影响,不具导致高死亡率的确定性.笔者推断大眼幼体之间的相残不一定是育苗生产活动中大眼幼体高死亡率的最直接和最主要的原因,高死亡率可能是第Ⅴ期溞状幼体和大眼幼体之间、大眼幼体和第Ⅰ期仔蟹之间的相残,或恶劣环境下大眼幼体相互抱缠的习性造成机械损伤所致.     

锌及其蛋氨酸螯合物对中华绒螯蟹生长的影响

研究了鱼粉—豆饼饲料中添加硫酸锌及蛋氨酸锌对中华绒螯蟹生长的影响.分五个水平添加锌，即20mg/kg，40mg/kg，80mg/kg，160mg/kg，200mg/kg饲料.其中200mg/kg水平用蛋氨酸锌添加，其它水平分别以硫酸锌和蛋氨酸锌两种形式添加，对照组不添加.试验期为49d，试验结果表明，河蟹的鱼粉—豆饼饲料中加硫酸锌，对其增重率和存活率均无明显影响，但其肝、胰脏的锌含量在添加20mg/kg及其以上水平时达到最大.蛋氨酸锌组的增重率高于同水平的硫酸锌组，但除了40mg/kg水平外，差异不显著(P＞0.05)，蟹体锌含量高于对照的9.9%～13.4%.     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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