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61.
甜菜渣对中国对虾消化酶的影响研究 总被引：3，自引：0，他引：3
于１９９６年１０月在中国科学院海洋研究所选取人工养殖中国对虾（平均体长９．０２ｃｍ），以双缩脲法测定消化器官的蛋白含量；福林一酚试剂法测定蛋白酶活力；Ｓｏｍｏｇｙｉ比色法糖法测定淀粉酶和纤维素酶活力，同时研究中国对虾配合饵料中添加１０％的甜菜渣或１０％经不同方法处理的甜菜渣时，对消化器官蛋白酶、淀粉酶、纤维素酶活力变化的影响。结果表明，在饵料中添加１０％甜菜渣 经不同方法处理的甜菜渣饲喂中国对虾， 相似文献
62.
蜕皮激素是甲壳动物主要的内分泌物质之一，属蜕皮甾类(MH)，具有特异的生理功能。目前的资料对蜕皮激素可以诱导蜕皮的看法比较一致；也有一些学者认为它能加速蛋白质和DNA的合成(罗日祥、王玉英，1984; Lowe, M. E., D. H. S. Horn and M. N. Galbraith, 1968; Neufeld, G、J., J. A. Thomson and D. H. S. Horn, 1968),但论据还不够充分。对于蜕皮激素在虾体各组织中的分布，Gorell, Gilbert and Siddall(1972)用同位素标记示踪的方法在Orconectes virilis 作过研究。Chang and O’connor(1978)对粗腿厚纹蟹(Pachygrapsus crassipes)各组织中的蜕皮激素作过定性定量的研究。为了探索蜕皮激素在中国对虾(Penaeus orientalis)体内的生理功能，本文报道了以放射免疫分析法对对虾各器官组织中的蜕皮甾类含量的测定结果。 相似文献
63.
Zhu Jichang Feng Youliang Meng Qing-Ren Wu Fengcheng Li Hao Liu Haitao Zhang Feipeng Wang Tianyu Wu Guoli Zou Caineng Zhu Rixiang 《中国科学:地球科学(英文版)》2019,62(11):1783-1804
We present the results of Mesozoic sequences of the Bohai Bay basin in North China, based mainly on geochronology and interpretations of seismic profiles and logging data. Five tectono-stratigraphic sequences are defined: Lower-Middle Triassic, Lower-Middle Jurassic, Upper Jurassic, Lower Cretaceous and Upper Cretaceous. Based on an analysis of detrital zircons, the clastic rocks recorded two intervals of Jurassic magmatic activity, during 180–175 and 160–152 Ma, which can be correlated to the Nandaling and Tiaojishan Formations in the Yanshan area, respectively. However, since Jurassic volcanic rocks have not yet been found in the Bohai Bay basin, we speculate that these two stages of activity were mainly concentrated around the periphery of the North China Craton(NCC) rather than within. Based on an analysis of zircons from volcanic rocks and pyroclastics, the early Cretaceous magmatism in the Bohai Bay basin can be divided into two stages, 125–120 and 110–100 Ma,which can be correlated to magmatism in the eastern part of the NCC. The zircon ages indicate an absence of volcanic activity during the late Tuchengzi and Zhangjiakou periods which may correlate to the uplift of the Bohai Bay basin in the late Late Jurassic. Comparison of the development of Mesozoic basins and sedimentary strata in the central-eastern part of Yanshan tectonic belt and the the Bohai Bay basin indicates that the two areas are generally comparable, but with substantial differences.The central-eastern part of the Yanshan structural belt lacks Early-Middle Triassic strata, and the Bohai Bay basin lacks late Jurassic-early Cretaceous strata. Based on research results from late Mesozoic sedimentary structures in the central and eastern parts of the Yanshan tectonic belt, we infer that episode A of the Yanshanian Orogeny was weak in the Bohai Bay basin and its periphery, while episode B of the Yanshanian Orogeny had a strong influence on the Bohai Bay basin and its periphery. The available data reveal differences in the expression of these episodes: the Bohai Bay basin is characterized by vertical uplift, and the northern margin of NCC is characterized by horizontal compression uplift. 相似文献
64.
中药制剂对中国对虾免疫活性物的诱导作用 总被引：60，自引：0，他引：60
分别于１９９４年和１９９５年９－１０月以胶州湾海捕中国对虾为材料，取其血淋巴测定血凝素活力，溶菌活力，并以投喂添加ＶＣ，ＶＢ６，中药制剂１号，中药制剂２号的药饵１７ｄ，２５ｄ后的免疫性的活力动态变化， 相似文献
65.
从古地磁研究看中国大陆形成与演化过程 总被引：12，自引：1，他引：11
古地磁学是进行大陆板块或微板块(地块)运动演化过程和古地理重建的最有效手段之一。近半个世纪以来,通过中外学者艰苦卓绝的努力,在中国大陆上积累了大量的古地磁数据,为中国大陆各主要块体的起源、构造演化和碰撞拼合过程等提供了定量约束。文中根据现代古地磁数据可靠性判别标准,对扬子、华北及塔里木地块显生宙古地磁数据进行了重新分析和筛选,结合拉萨和喜马拉雅地块的古地磁数据,对中国大陆的形成和演化提出了几点认识:(1)古生代中国大陆各主要块体基本位于赤道附近的低纬度地区;早古生代扬子、华北及塔里木地块与东冈瓦纳大陆关系密切;(2)中生代是中国大陆各主要块体发生碰撞和拼合的主要时期;(3)中国大陆主要块体间的碰撞和拼合具有局部首先碰撞、相互旋转、完全拼合、陆内挤压造山和伸展反弹的特点。 相似文献
66.
Lingqun Zeng Biao Wan Rixiang Huang Yupeng Yan Xiaoming Wang Wenfeng Tan Fan Liu Xionghan Feng 《Geochemical transactions》2018,19(1):12
Recently, the wide application of CuO nanoparticles (NPs) in engineering field inevitably leads to its release into various geologic settings, which has aroused great concern about the geochemical behaviors of CuO NPs due to its high surface reactivity and impact on the fate of co-existing contaminants. However, the redox transformation of pollutants mediated by CuO NPs and the underlying mechanism still remain poorly understood. Here, we studied the interaction of CuO NPs with As(III), and explored the reaction pathways using batch experiments and multiple spectroscopic techniques. The results of in situ quick scanning X-ray absorption spectroscopy (Q-XAS) analysis verified that CuO NPs is capable of catalytically oxidize As(III) under dark conditions efficiently at a wide range of pHs. As(III) was firstly adsorbed on CuO NPs surface and then gradually oxidized to As(V) with dissolved O2 as the terminal electron acceptor. As(III) adsorption increased to the maximum at a pH close to PZC of CuO NPs (~?pH 9.2), and then sharply decreased with increasing pH, while the oxidation capacity monotonically increased with pH. X-ray photoelectron spectroscopy and electron paramagnetic resonance characterization of samples from batch experiments indicated that two pathways may be involved in As(III) catalytic oxidation: (1) direct electron transfer from As(III) to Cu(II), followed by concomitant re-oxidation of the produced Cu(I) by dissolved O2 back to Cu(II) on CuO NPs surface, and (2) As(III) oxidation by reactive oxygen species (ROS) produced from the above Cu(I) oxygenation process. These observations facilitate a better understanding of the surface catalytic property of CuO NPs and its interaction with As(III) and other elements with variable valence in geochemical environments. 相似文献
67.
ZHAI Mingguo ZHU Rixiang LIU Jianming MENG Qingren HOU Quanlin HU Shengbiao LIU Wei LI Zhong ZHANG Hongfu & ZHANG HuafengKey Laboratory of Mineral Resources Institute of Geology Geophysics Chinese Academy of Sciences Beijing China Correspondence should be addressed to Zhai Mingguo 《中国科学D辑(英文版)》2004,47(2):151-159
An important tectonic inversion took place in eastern North China Block(NCB) during Mesozoic, which caused a great lithosphere thinning, reconstruction of basin-range series, powerful interaction between mantle and crust, a vast granitic intrusion and volcanism, and large-scale metallogenic explosion. The time range of the Mesozoic tectonic regime inversion in the eastern North China Block is one of the key issues to understand mechanism of tectonic regime inversion. Our updated results for recognizing the time range are mainly obtained from the following aspects: structural analyses along northern and southern margins of the NCB and within the NCB for revealing tectonic inversion from compression to extension and structural striking from -EW to NNE; geothermic analyses of the eastern sedimental basins for a great change of thermal history and regime; basin analysis for basin inversion from compression to extension and basin migration from -EW to NNE; petrological and geochemical studies of volcanic roc 相似文献
68.
Effects of the mixture of β-ecdysone and polypodine -B (2 : 1 W/W) on the moulting and growth of prawn, Penaeus orientaliss were studied in laboratory by rearing the animal with the added compound diets. The results showed that the addition of the moulting hormone (M. H) mixture to compound diets, from 1. 33× 10-6 to 30×10-6, could increase moulting activity and growth rate of the prawn to different extents, among which the 5. 33× 10-6-10. 67×10-6addition had statistically significant effects. However, 60 × 10-6 added diets caused moulting and growth inhibitions and cuticle thickening. The analyses of protein, water and ash contents of the prawn showed no remarkable differences between hormone dosed animals and the control. 相似文献
69.
峨眉山大陆溢流玄武岩是中国唯一被国际学术界认可的、地幔柱成因的大火成岩省。峨眉山玄武岩的主相喷发时间约为260Ma,与二叠纪晚瓜德鲁普期生物灭绝事件的时间相当。地球动力学模拟结果显示,地幔柱活动不仅与超静磁带的产生和结束有密切联系,而且地幔柱活动可能引发生物大灭绝。文中讨论了前人对峨眉山玄武岩的来源、成因以及喷发与持续时间等重要研究进展,并基于新的古地磁研究结果,探讨了峨眉山玄武岩与Kiaman负极性超静磁带(KRS)和二叠纪晚瓜德鲁普期生物灭绝事件的联系以及相应的地球动力学含义。 相似文献
70.
A statistical model for the quick reversals during a geomagnetic pole transition is put forward by combining the modern geomagnetic field and paleomagnetic field. The decrease of geomagnetic intensity determines the reversals, and the quick reversals are possibly caused by the interaction between g01 and the other geomagnetic components. 相似文献