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1.
不同水温对文昌鱼性腺发育的影响 总被引:10,自引:1,他引:10
研究表明,不同水温对文昌鱼性腺发育分化和成熟有十分显著的影响。14℃对文昌鱼性腺发育没有显著的作用,20和25℃十分有利于性腺发育和成熟,经40d培养,出现一些雌、雄文昌鱼产卵和释精以及加速性腺发育。本文还讨论了水温促进性腺发育可能的机制。 相似文献
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本文通过对铜厂铜矿的S,H,O和C同位素地球化学研究,认为本矿床属于与闪长岩有关的中低温硫化物矿床,在成矿阶段的实始热液为岩浆水,含矿流体是一种岩屑水与天水混合而K^+混合流体,矿床中S主要来源于细碧岩,部分来源于闪长岩,推测成矿物质来源物质也来源于细碧岩。 相似文献
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Considerable attention has been paid in recent years to the study of geothermal history by using spontaneous fission tracks of 238U recorded in minerals.Apatite and zircon were used for fission track study in this paper because apatitie has been widely used as a natural geothermometer(Wang Shicheng et al., 1994) to reveal the thermal evolution of sedimentary rocks based on its low annealing temperature of fission tracks and zircon is characterized by a closing temperature above 700℃,The samples were collected from ferruginous,siliceous slate wall rock at the upper levels of the orebody and Nb-REE-Fe ores from deep tunnels.The age and thermal evolution of the orebody were discussed in terms of fission track characters and their length variations observed in the coexisting apatite and zircon in the same specimen. 相似文献
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The sphalerite oxidative kinetics under hypergene condition was simulated and studied by means of a mixed flow reactor over a pH range of 1.0 7.8,and at dissolution temperatures from 20 to 55℃,ferric ion concentrations from 1.0×10-5 to 1.0×10-2 mol/L,O 2 flux of 0.5 L/min,and oxidants of ferric ion and O 2.It is indicated that with ferric ion as oxidant,the oxidation rate of sphalerite increases with increasing ferric ion concentration,temperature and decreasing pH value,and under the studied conditions,the dissolution rates of Zn and Cd are approximately identical,with the values of activation energy being 41.75 and 42.51 kJ·mol-1,respectively,suggesting that the oxidation rate of sphalerite is controlled by chemical reactions on mineral surface.However,with O 2 as oxidant,the oxidation mechanism of sphalerite varies with pH value.Oxidation rate decreases with increasing pH value when pH is lower than 5.95,whereas the increase of pH value results in an increase in oxidation rate when pH value is higher than 7.The oxidation rate of sphalerite can be expressed as:R Zn =10 1.1663 [Fe3+] 0 0.154 ·[H+] 0.2659 ·e-41.75/RT or R Cd =10 1.7292 [Fe3+] 0 0.170 ·[H+] 0.2637 ·e-42.51/RT 相似文献
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Most altered clay minerals in uranium ore deposits in granites in the selected provinces of South China haveδ
18O
m
values ranging from 6.22 to 7.24,δDm from −60 to −70,δ
18O
from +3.05 to −3.07, and
from −20.2 to −37.5‰. Relative enrichment of32S in the uranium ore deposits and greater variations in Pb isotopic composition of galenas from them show that uranium ores
in the granites were formed in such a way that uranium in shallow-source granites had been mobilized by heated meteoric waters
and then migrated to local favourable locations along great faults to form uranium ore deposits.
Zhang Shaoli, Yang Wenjin, Tang Chunjing and Xu Wenxin did part of this work. 相似文献
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新疆氯铜矿的发现及其意义 总被引:2,自引:0,他引:2
在新疆“三○五”项目的研究工作中,发现了氯铜矿(Atacamite)Cu2(OH)3Cl,其化学成分、粉晶数据、红外吸收光谱、差热分析和物理特征等与标准氯铜矿(智利)基本一致。这是我国首次在自然界发现的氯铜矿。它和本区一系列卤化物的发现,从某种程度上反映了该区成矿环境,表明在该区可以通过原生卤素晕寻找铜矿床和银矿床,具有非常重要的意义。 相似文献
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贵州都匀牛角塘富镉锌矿床中镉的分布及赋存状态探讨 总被引:9,自引:0,他引:9
对贵州都匀牛角塘富镉锌矿的研究发现该矿床高度富集镉 ,矿石中镉含量一般为 2 2 84× 1 0 -6~ 9850× 1 0 -6,最高为 1 3 4 0 0× 1 0 -6,比地壳克拉克值 ( 0 .2× 1 0 -6)高 5~ 6个数量级 ,比工业品位高n× 1 0~n×1 0 2 倍 ,且其储量达到大型矿床的规模 ,在世界上十分罕见。镉主要以类质同象存在于闪锌矿中 ,少量镉以硫镉矿等独立矿物形式存在于矿床的氧化带 ,是风化淋滤过程中形成的镉的次生矿物。 相似文献
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针状白云母产于新疆科科托海附近辉长岩-闪长岩内含稀有元素的3号伟晶岩脉中,呈针状或纤维丝状产出,长短轴之比一般大于1:80,最大达1:500。它的晶体结构、化学组成、物理和光学性质与普通白云母相同或类似,属于普通白云母。依据针状白云母产出的地质构造环境和与剪切裂隙的关系,笔者认为针状白云母可能是结晶粗大的白云母在其形成过矿中和形成以后受到垂直于(001)晶面压应力作用,产生三组微裂隙,并沿其中一组发育完全的微裂隙裂开而成。 相似文献