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1.
在水温为21.4℃—31.2℃,盐度为27.2‰—36.3‰的环境条件下,进行了企鹅珍珠贝培育附壳珍珠的研究。经287天的育珠,成活率87.5%。在收获的15个母贝中,植入直径为7~10mm的珠核47粒,佛像模型2个;收获附壳珍珠40颗,佛像2个,留核率达85.7%。其中商品珠35颗,商品珠率为83.3%。在商品珠中,珠色为银白色的16颗,占45.7%;金黄色的16颗(包括1佛像),占45.7%;污斑珠3颗,占8.6%。珍珠直径超过11mm的有5颗,10.0~10.9mm的有19颗,9.0~9.9mm的有9颗,8.0~8.9mm的仅1颗。抽测珍珠5颗,珠层厚度最大者862.5μm,最薄者562.5μm。  相似文献   

2.
不同食物与放养水层对九孔鲍生长的影响   总被引:5,自引:1,他引:4  
采用室内池子多层笼养殖方式,以加工海带、鲜江蓠与A,B2种片状饲料为饵料,试验了不同食物与不同放养水层对九孔鲍生长影响,结果表明:(1)从壳长增长上,海带与饲料B近似,各为11.3与11.2mm;其次为饲料A,10.2mm;而江蓠最差,仅7.7mm;(2)在体重增长上,以饲料B最高,平均每只为3.3g,其次为饲料A与海带,平均每只2.9g,而江蓠仅1.8g;(3)从试验期间所获体重增长比壳长增长看,两种饲料(B为295,A为284mg/mm)均比两种海藻高(海带为257,江蓠为234mg/mm);(4)从垂直11层笼子九孔鲍生长的比较,下层的好于上层,越是下层越好,投喂两种饲料在体重上差别更明显。  相似文献   

3.
九孔鲍室内流水养殖   总被引:3,自引:0,他引:3  
设计了陆上室内流水养成池和育苗池进行集约化养鲍。每个养成池7.0m×5.0m×1.8m,放鲍笼1254个,每笼放养壳长2cm的九孔鲍40 ̄45只,投喂新鲜江蓠。经8 ̄10个月的饲养,鲍壳长可达6cm,成活率达70% ̄85%。  相似文献   

4.
东昆仑祁漫塔格-都兰成矿带是青海省重要的矽卡岩型铁多金属成矿带,胜利矽卡岩型铁铜矿床位于该成矿带东段,其成矿作用与二长花岗岩密切相关,矿体产于二长花岗岩与大理岩接触带的矽卡岩中。地球化学数据显示,胜利铁铜矿床二长花岗岩w(SiO2)为 71.84% ~74.50%,w(K2O+Na2O)为 8.03% ~8.61%,明 显 富 碱;K2O/Na2O 为 1.28~1.62,相 对 富 钾;A/CNK为0.95~0.98,属于准铝质高钾钙碱性I型花岗岩。岩石总体富集大离子亲石元素 K、Ba、Rb和活泼不相容元 素 Th、U,相对亏损高场强元素 Ta、Nb、P、Ti等。样 品 稀 土 元 素 总 量 w(∑REE)=132.73×10-6~181.36×10-6,(La/Yb)N 为7.40~11.67,δEu为0.67~0.78,稀土元素配分曲线呈右倾型,具有较明显的轻稀土元素富集、重稀土元素亏损的特征,具 Eu负 异 常。二长花岗岩 LA-ICP-MS锆石 U-Pb加权平均年龄为(240.5±2.8)Ma,形成于中三叠世。综合研究表明,二长花岗岩是阿尼玛卿洋盆向北俯冲,致使壳幔岩浆发生混合,后经侵位、结晶分异形成。   相似文献   

5.
池塘培育的鲢仔稚鱼(6.8—32.2mm)食性可分为浮游动物和浮游植物为主的二个阶段。食性的转化取决于消化系统各器官的发育分化。全长15mm左右为食性转化阶段。全长27.9~32.2mm,食性接近成鱼。口宽(MW)、口高(MH)与全长(L)的关系分别为:MW=-401.99+92.62L、MH=-221.62+49.66L;肠长/全长(K)与全长(L)的关系为:K=-0.1248+0.0713L;第Ⅰ列外侧鳃耙数(GN)与全长(L)的关系为:GN=-67.44+8.93L;全长(L)体重(W)和时间(t)的关系分别为:L=4.537+1.417t、W=2.785e0.2873t。以上回归方程经统计检验均为高度显著相关。  相似文献   

6.
大珠母贝人工苗工厂化分组标粗;室内养殖54d,贝苗平均壳高从入池时6.61mm增长至13.08mm,最大为14.25mm,平均成活率31.9%,最高达49.8%。试验结果初步表明:1.大珠母贝岸上室内工厂化养殖不但可行,而且也将是解决当前海上养成困境的一条出路;2.发现自然海区中也存在饥饿死亡现象及死亡潜伏期,反映出海上养殖高死亡率的复杂性;3.人工配合饲料的应用显著提高了贝苗的增长率和成活率,显示出广阔的商业价值。  相似文献   

7.
在野外地质工作基础上,运用岩石地球化学方法,通过主量元素、稀土元素和微量元素研究,探讨了水洞岭矿区石英角斑岩的岩石化学特征、形成环境及其与成矿的关系。研究表明:石英角斑岩的w(SiO2)=73.11%~79.30%,w(K2O)=1.20%~5.99%,w(Na2O)=1.57%~4.61%,w(K2O+Na2O)=4.82%~8.67%,Na2O/K2O=0.45~3.49,ACNK=0.99~1.25。稀土元素总量w(ΣREE)=70.19×10-6~198.75×10-6,轻稀土元素富集,重稀土元素亏损,轻重稀土元素分馏明显((La/Yb)N=3.65~8.20),Eu中度至轻度亏损(δEu=0.53~0.96);大离子亲石元素(Rb、Ba、Th、U、K)和 Pb等元素富集,高场强元素(Nb、Ta、Ti、P)和Sr等元素亏损。综合表明水洞岭矿区石英角斑岩形成环境类似于洋壳俯冲成因的火山弧环境。   相似文献   

8.
含水层沉积物是江汉平原地下水中砷的主要来源,沉积物地球化学特征对地下水的水化学具有重要控制作用。为查明江汉平原第四系沉积物中砷的垂向分布及赋存环境,在典型高砷地下水分布区内选取2个深钻(JH002孔及 YLW01孔,深度分别为230m 和201m)采集沉积物样品进行了地球化学分析。结果表明全新统和上更新统含水层沉积物以黏土、粉土、淤泥质黏土、粉砂、细砂为主,指示着弱水动力的沉积环境;2个钻孔沉积物地球化学特征相似,w(As)=2.0~22.6mg/kg(平均9.0mg/kg),w(Fe)=11.8~55.0mg/g(平均37.8mg/g),w(S)=0.1~2.1mg/g(平均0.4mg/g)。中、下更新统沉积物岩相变化较大,以砂和砾石居多,局部含有黏土夹层,指示着沉积时较强的水动力沉积环境;其中JH002孔沉积物 w(As)=2.7~160.5mg/kg(平 均40.9mg/kg),w(Fe)=20.1~179.5mg/g(平均50.5mg/g),w(S)=0.1~17.7mg/g(平均4.9mg/g);YLW01孔沉积物砷、铁、硫质量分数均低于JH002孔,w(As)=5.2~56.1mg/kg(平 均16.2mg/kg),w(Fe)=10.9~117.5mg/g(平 均36.4mg/g),w(S)=0.3~7.8mg/g(平均1.8mg/g)。YLW01孔中、下更新统沉积物颗粒较JH002孔更细,所处的水动力条件更弱,砷、铁、硫质量分数均低于JH002孔,说明沉积历史环境影响着砷、铁、硫等元素的分布。沉积物地球化学数据聚类分析结果表明全新统和上更新统砷与铁具有显著的相关性,而中、下更新统沉积物砷与硫化物矿物紧密相关。结合不同深度含水层水化学特征差异指示上更新统含水层中含砷铁氧化物的还原性溶解导致浅层地下水中砷的富集,富硫的中、下更新统深层含水层中强还原环境下砷受到硫化物矿物的固定作用难以释放进入地下水中。   相似文献   

9.
采用标准偏差方法提取了延庆盆地阜高营剖面湖相沉积物的敏感粒度组分,得出粗粒敏感组分2(26~159μm)能有效指示冬季风的强弱。根据经验正交函数(EOF)对其整体粒度进行了分解,其中 EOF1组分(<22μm)的贡献率高达53.8%,指示降水量的多少。研究显示,粗粒敏感组分2与 EOF1组分比值的变化可以作为研究区冬季风强弱和干旱化的指标,粗粒敏感组分2增加,EOF1组分减少,表明冬季风加强,气候变干,湖泊发育受限。研究区冬季风演化过程表现出冰期-间冰期旋回特征:56.8~45.6ka冬季风弱,降水量大,湖面较高;45.6~31.5ka冬季风开始加强,降水量减少,水位略有下降;31.5~13.4ka冬季风强盛,降水量较少,湖泊趋于萎缩;13.4ka至今冬季风微弱,降水适中,湖泊发育缓慢。   相似文献   

10.
从北部海沿海采捕的日本鬼You(Inimicus japonicus)亲鱼,经暂养后进行催产,雌鱼每千克体重注射LRH-A310-μg+DOM5mg或HCG600~800IU+LRH-A330~40μg;雄鱼注射同样药物,剂量减半。共采卵109万粒,平均受精率89.0%,平均孵化率为90.0%,共培育出体长1.8~2.8cm的幼鱼26.8万尾,平均成活率30.7%。  相似文献   

11.
12.
Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.  相似文献   

13.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.  相似文献   

14.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied  相似文献   

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16.
《山地科学学报》2014,(4):I0004-I0009
<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet.  相似文献   

17.
<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by  相似文献   

18.
Foreword     
正Rapid changes of Arctic sea ice cover have been in the focus of the international climate research community in recent years.Quite a few of nations have completed a large number of related surveys and research projects in the Arctic Ocean.Up to now,China has performed six research cruises to the Arctic Ocean resulting in a significant volume of research output.Improved knowledge on the atmospheree-sea ice-ocean interactions in the Arctic is a  相似文献   

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20.
The GRV 024516 and GRV 024517 meteorite samples collected from Grove Montains,Antactica are ureilite and H5 ordinary chondrite,respectively.Based on the study of mineralogy-petrology,the cosmic-ray exposure ages and gas retention ages of these two meteorites were determinated and calculated.Their cosmic-ray exposure ages are 33.3 Ma,51.7 Ma,and gas retention ages are 1936.8 Ma and 3720 Ma,respectively.The ureilite contains diamond,graphite and amorphous C,which are mainly carrier of noble gases indicating obviously shock metamorphism effects,which induced 40Ar partial loss.The H5 chondrite indicates thermal metamorphism of parent body,its gas retention age fall the range between 3220 Ma and 4510 Ma of the least shocked H5 chondrites  相似文献   

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