电加热自动控制提前孵化鱼苗

电加热自动控制提前人工孵化鱼苗，它采用机械化．电气化．自动化连续生产。它完全用人为的方法创造一个适宜孵化的生态环境，使鱼苗孵化的主要指标均达到目前国内最好水平，它为实现我国水产养殖业工厂化奠定了科学技术基础，它比只利用天然水体人工常规孵化有显著的优越性和经济效益，值得推广。     

电加热自动控制提前孵化鱼苗

电加热自动控制提前人工孵化鱼苗,它采用机械化、电气化、自动化连续生产。它完全用人为的方法创造一个适宜孵化的生态环境,使鱼苗孵化的主要指标均达到目前国内最好水平,它为实现我国水产养殖业工厂化奠定了科学技术基础,它比只利用天然水体人工常规孵化有显著的优越性和经济效益,值得推广。     

淡水螯虾类胚胎离体孵化技术研究进展

【目的】综述淡水螯虾类胚胎离体孵化技术的主要研究成果,为提高孵化效果及出苗同步性,节省人力、物力,实现数字渔业与智慧渔业奠定基础。【方法】从胚胎与初孵幼虾生物学、影响离体孵化的环境因素、影响离体孵化的人为调控因素、离体孵化装置、研究展望等五个方面介绍国内外的一系列研究成果。【结果】离体孵化期间应将水温、水质控制在适宜水平,定期进行消毒,离体胚胎的发育阶段及孵化密度、孵化装置等是重要影响因素之一,必要的人工管理措施也是决定孵化成功与否的关键。【结论】离体孵化技术应用于淡水螯虾类意义重大,而控制适宜的环境条件及应用合理的管理措施是基础。今后在离体孵化装置的优化、离体孵化期间水质与菌群环境的维持、死卵与死虾的挑除、苗种生产的批量化与智能化等方面进行深入研究,实现孵化效率质的提升,更好地应用于实际生产。     

两种脱粘剂脱粘孵化效果的比较

在淡水鱼类的人工繁殖中,如鲤、鲫、团头鲂等粘性鱼卵,如果我们采用鱼卵附着鱼巢孵化的方法,则存在着孵化效果不稳定,鱼巢制作、架设、管理繁琐,鱼苗数量不易掌握等缺点,因而不能适应当前生产实践和科学实验的需要,故粘性鱼卵的孵化方法,应以脱粘、流水孵化的效果较好。据报导,国外有以单宁(Tannine 即制皮革所用的鞣酸)作为粘性鱼卵的脱粘剂。我们于1975年6-7月在顺德县开门办学期间,曾做过棱鲫与鲮的杂交试验,因棱鲫属粘性卵,故在人工杂交后,我们分别以泥浆水、单宁作为脱粘剂,进行了脱粘、孵化效果的比较,现将初步试验结果,报导如下。     

九江二井井口供水系统设计初探

针对九江地震台地下流体水化学监测用水、地震氡观测仪器检测平台检测用水和日常生活用水需求,结合九江二井流量、水质和水温等现状设计一套综合井口供水系统。该供水系统在保证地下流体水化学监测用水和其他用水无流体力学干扰的前提下,可较好满足台站监测、检测和生活用水要求。     

硝化细菌对罗非鱼苗培育环境及抗病力的影响

于罗非鱼鱼苗培育水体中引入不同浓度的硝化细菌,检测主要水质因子,测定罗非鱼与抗病力有关的酶的活力,研究微生态调控对水质和对罗非鱼抗病力的影响。结果显示,硝化细菌浓度为100/L时,氨氮含量相对于对照组降低25.05%,亚硝酸氮含量降低45.16%,COD值降低12.33%,差异显著(P<0.05);鱼苗培育成活率相对于对照组高7.58%,体长增加22.18%,体重增加46.15%;幼鱼的抗菌酶、碱性磷酸酶(AKP)和超氧化物歧化酶(SOD)活力相对于对照组分别提高18.60%、59.19%和49.89%,差异显著(P<0.05),组织过氧化物酶(POD)活力差异不显著。表明不同浓度的硝化细菌可显著改善罗非鱼苗培育环境的水质,增强罗非鱼苗的抗病力。     

5种波长光对日本沼虾人工育苗幼体成活率的影响

光照与日本沼虾繁殖和孵化关系极为密切。研究了不同波长的光对日本沼虾孵化的影响，结果表明：在环境光谱主峰值470．5nm、477．9nm、492．6nm、504．8nm和615．2nm条件下，适度成熟的亲虾都能顺利孵化，日本沼虾孵化与否，与孵化环境中的光波波长无关，而与抱卵日本沼虾胚胎发育有关。日本沼虾在孵化期对不同波长的光谱有明显的视觉敏感度分布，在前4种光谱条件下，日本沼虾视觉器官敏感，而在光谱主峰值615．2nm时日本沼虾视觉器官不敏感。这一特点在日本沼虾育苗生产上具指导意义，可防止抱卵亲虾在孵化过程中吞食幼体，提高幼体成活率。     

北京市市区白垩系裂隙孔隙承压水化学牲及水质评价

从城市供水角度来讲,水资源质量是满足用水要求、作为确定供水水源及水用途的一个重要内容。本文研究对象为北安市市区内城市供水目的水层一白垩系裂隙孔隙承压水。根据研究需要,在该区不同位置取18套水样进行水质常规分析,并对其物理、化学特征进行分类总结,通过生活饮用水、工业用水、农业用水等3个方面对其水质进行评价。     

人工繁殖的家鱼发生退化原因的探讨

近几年来,根据生产单位的反映,人工繁殖的家鱼有退化的迹象,具体表现在体质较差,生活力降低,生长缓慢、成熟个体小、死亡率高等。因而,他们认为,人工繁殖的鱼苗培育的鱼种比不上天然鱼苗培育的鱼种好,这是生产上的重要问题之一。伟大领袖和导师毛主席教导我们:“有比较才能鉴别”。我国过去的塘鱼生产,数千年来都是依靠天然鱼苗,为什么家鱼没有发生退化?而鱼苗人工繁殖只不过十多年的历史,家鱼就出现退化的迹象,这是值得探讨的问题。因此,我们遵照毛主席的伟大教导,在每次开门办学期间,都对此问     

水资源水质水量结合评价方法及其应用

在以往的水资源评价中,水质、水量是分开评价的,这样无法知道评价区不同类型的水有多少量,而这恰恰是评价结果的使用者所关心的.本文结合北方地区实际,提出了一种以用水为主体的水质水量结合评价方法.     

长葛县规划区地下水化学特征及其成因分析

本文根据长葛市规划区地下水化学分析资料 ,利用污染指数法对该区地下水化学特征及其成因进行了初步分析 ,指出该区局部地下水的总硬度、溶解性总固体、硝酸盐污染指数大于 1的原因是生活、工业废物处理不当和引用污水灌溉而引起 ,并提出了该市地下水污染治理的建议     

Study on Dissolved Trace Metals in Sea Surface Microlayer in Daya Bay

Glass-plate sampling during 1988- 1999 in Daya Bay and suitable corresponding analytical methods were used for the measurement of dissolved trace metals, dissolved organic carbon, biological oxygen demand, chemical oxygen demand, salinity of the sea surface mierolayer and subsurface water. Apparent enrichment mechanism and diurnal variation have been revealed for dissolved trace metals in the microlayer in Daya Bay. The more dissolved organic matter was enriched in the sea surface microlayer, the more dissolved trace metals were enriched in the layer. The organic matter played an important role in the enrichment process. The diurnal variations of dissolved trace metals showed that their concentration was apparently inversely related to the tide activity that the concentration was low during rising tide, but high during falling tide. The behavior of dissolved trace metals expressed by the diurnal variation was clearly opposite to that of salinity.     

天然水CaCO_3侵蚀量与沉淀量的计算

天然水ＣａＣＯ３侵蚀量与沉淀量的计算是岩溶地球化学研究中的一个重要问题，本文在指出有关文献对这一问题的处理存在严重问题的同时，提出了天然水ＣａＣＯ３侵蚀量与沉淀量计算的新方法。该方法以水溶液相对ＣＳＣＯ３饱和度的计算为基础，对ＣａＣＯ３溶解或沉淀所引起的水溶液ｐＨ值、组分的活度系数以及水溶液中各组分存在形式含量的变化统一地作了考虑，且区分开放系统与封闭系统两种不同的情况分别进行了计算。实际水样的计算结果表明，计算中若不考虑上述的种种变化，则计算结果的误差将是相当大的。     

In-situ determination of sediment oxygen demand in cultivation ponds

ＩＮＴＲＯＤＵＣＴＩＯＮＳｅｄｉｍｅｎｔｏｘｙｇｅｎｄｅｍａｎｄ(ＳＯＤ)ｉｎｃｌｕｄｅｓｂｉｏｌｏｇｉｃａｌａｎｄｃｈｅｍｉｃａｌｏｘｙｇｅｎｄｅｍａｎｄ(ＧｅｏｒｇｅａｎｄＪｏｓｅｐｈ,1980),ｉｓａｎｉｍｐｏｒｔａｎｔｆａｃｔｏｒａｆｆｅｃｔｉｎｇｄｉｓｓｏｌｖｅｄｏｘｙｇｅｎ(ＤＯ)ａｎｄｈａｓｂｅｃｏｍｅａｎｉｍｐｏｒｔａｎｔｐａｒａｍｅｔｅｒｉｎｍａｎｙｗａｔｅｒｑｕａｌｉｔｙｍｏｄｅｌｓｆｏｒｃｕｌｔｕｒｅｐｏｎｄｓ(Ｍａｄｅｎｊｉａｎ,1990;Ｆａｎｇ,1991).Ｓｏｉｔｉｓｎｅｃｅｓｓａｒｙｔｏ…     

Characteristics and formation causes of Qingdao Cold Water Mass

In this work,the main characteristics of the Qingdao Cold Water Mass were studied by using“the comparison analysis method”based on 1980 temperature,salinity and dissolved oxygen data on the western South Yellow Sea.The formation cause of the water mass was analyzed based on February of 1959 temperature and salinity data for this area and on some other authors’studies.The results showed that the Qingdao Cold Water Mass has growing and vanishing processes：appears in the last ten days of March;has stable pattern in April;is biggest in its area in May;becomes small in its area in June;vanishes in July.It comes from the northem Shandong Coastal Water and is characterized by low temperature and salinity and high disolved oxygen.The mass is formed under the joint effects of anticyclonic circulation and solar radiation.     

Study on kinetics of cathodic reduction of dissolved oxygen in 3.5% sodium chloride solution

Electrochemical reduction of dissolved oxygen in seawater on metals is of great importance for corrosion studies. The present paper studied cathodic reduction of dissolved oxygen on Q235 carbon steel in 3. 5% sodium chloride(NaCl)solutions by cyclic voltammetry(CV), electrochemical impedance spectroscopy(EIS), rotating disk electrode(RDE)and rotating ring-disk electrode(RRDE). The cyclic voltammetric results demonstrated the cathodic process on Q235 carbon steel in O2-saturated 3. 5% NaCl solution contains three reactions:dissolved oxygen reduction, iron oxides reduction and hydrogen evolution. The peak potential of oxygen reduction reaction(ORR)is-0. 85 V vs Ag/AgCl, 3 molL-1 KCl. The E1S results indicated that the ORR occurring on Q235 carbon steel is a 4-electron process and that no finite diffusion is caused by the intermediate of H2O2 produced by ORR. The RDE and RRDE voltammograms confirmed the EIS results and it was found that the number of transferred electrons for ORR was nearly 4, I. E. , dissolved oxygen reduced to water.     

A VERTICAL DISTRIBUTION MODEL OF NUTRIENTS AND DISSOLVED OXYGEN IN THE SOUTHERN TAIWAN STRAIT

Sinoe vertical transport of nutrients and dissolved oxygen are quite important in the water col-umn and have drawn serious attention these recent years, a one-dmension numerical model is tried to simulate the vertical distribution of nutrients and dissolved oxygen in June at two research sites in the southemTaiwan Strait. Physical transport parameters are calibrated by temperature simulation, and thenare used to simulate the profiles of NO_3, PO_4 and dissolved oxygen. The simulation was generally success-ful for both stations. The importance of various factors, such as upwelling tidal current andbiogeochemical activities, which influence the vertical distribution of nutrients and dissolved oxygen, is revealed by analysis of the modeling results. Some important rates, fluxes and ratios are also estimated anddiscussed on the basis of simulation.     

SEA SURFACE SALINITY AND BOTTOM WATER OXYGENATED CONDITIONS IN WESTERN EQUATORIAL PACIFIC MARGINAL SEAS DURING THE LAST GLACLAL AGE

ImODUcrIONThewesternPadricconsistSofaseriesofrnarginalbasins(twoofwhicharetheSrsandSuluSea)thatareseparatalfromeachotherbysdriofvaryingdepths.The25OOmdepthsiliseparatingtheSrsfromthewesternNorthPadricallowiPadricinteediatewatertoentertheSCS.Inconhast,theSuluSeaiscomPldelysurmundedbyasill,mostofwhichisshallowerthanlOomindepth.Thedeepestchanne1intotheSLduSeais42Omdeep(MindoroStrait)andcutSacrossthesillthatseparateStheSuluSeafromtheSrs.TheseenvironmntSresultalinspeda1hydrographicse…     

桂林地区岩溶水中矿物和气体溶解量计算

本文在对桂林地区７４个岩溶水水样化学分析结果进行综合、归纳和分析之后认为，该区岩溶水化学成分是在当地雨水化学成分的基础上，经过水对岩石中的石膏、方解石及白云石和大气中的ＣＯ_２发生溶解作用而形成的。为了验证这一推论，笔者还运用质量守恒计算法，对上述水化学分析结果相对于当地雨水的矿物和ＣＯ_２气体溶解量进行了计算。文中还对岩溶水形成环境进行了分析和讨论。     

桐木沟热水沉积铅锌矿床同位素地球化学特征

本文探讨了东秦岭桐木沟热水沉积铅锌矿床中碳、氧、硫、锶和铅等同位素的地球化学特征。结果表明:碳、氧和硫分别源于海相碳酸盐和海水硫酸盐;铅和锶源于基底地层。