Study on halotolerance of phyllosoma larva of Chinese spiny lobster (Panulirus stimpsoni Holthuis)     

Chen Changsheng  Chen Zhengqiang  Hu Jiacai  Ye Zhaohong  Ji Dehu  Lan Liangchun 《海洋学报(英文版)》2001,20(3):409-415

INTRODUcrIONAs a quality seaha, lobster has a greater market demand or higher demand than supply. Inrecent years the natural resource of lobster is decreasing day by day due to overfishing oPera-tions. Conequently, an attention has been increasingly drawn to the development of artificialbreeding in lObster and seedstock preduction. From the l970s to the l980s the culture of lobsterlarva started but with very slow pngress. Inoue et al. (l978), Yamakawa et al. (1989), Kitta-ka and Kimura(l…  相似文献   

东海颗粒有机碳的研究   总被引：15，自引：1，他引：15  

刘文臣  王荣  吉鹏 《海洋与湖沼》1997,28(1):39-43

于１９９４年春季（４月）和秋季（１０－１１月）对东海颗粒有机碳（ＰＯＣ），颗粒氮，ＡＴＰ（三磷酸腺苷）进行测定，通过ＡＴＰ定量区分ＰＯＣ中的生命与非生命部分，结果表明，春秋两季ＰＯＣ的平均值为４１７μｇ／Ｌ其中春季为２８０μｇ／Ｌ，生命部分占１０％；秋季为５４１μｇ／Ｌ，生命部分占４％，春季表层ＰＯＣ以东海陆架中部为高值区同周围递减，与ＡＴＰ的分布相似，而且颗粒有机物中的Ｃ：Ｎ比值较低（７．６３）  相似文献   

胶州湾海水中溶解氨基酸的研究     

陆田生  纪明侯 《海洋与湖沼》1996,27(2):117-124

于１９８６年１月－１１月用高效液相色谱法分析胶州湾１０个站位表层和底层海水中溶解游离氨基酸（ＤＦＡＡ）的组成、含量的分布及其季节变化。结果表明，７个站位的表层海水中月平均总溶解游离氨基酸（ＴＤＦＡＡ）含量范围为１．２４－２．２８ｕｍｏｌ／Ｌ。多数站位在２月份处于最低值（０．４ｕｍｏｌ／Ｌ），１１月份达最高值（５．０ｕｍｏｌ／Ｌ）。所测氨基酸中，Ｇｌｕ，Ｇｌｙ、Ａｒｇ、Ｌｅｕ，Ｏｒｎ，Ｓｅｒ等占优势  相似文献   

饵料胆碱含量对真鲷仔稚鱼生长影响的初步研究   总被引：5，自引：0，他引：5  

刘镜恪  雷霁霖 《海洋科学》2001,25(11):42-44

采用胆碱强化活饵料的方法研究活饵料量中胆碱含量对真鲷仔稚鱼生长和成活率的影响。说明胆碱是仔稚鱼生长，存活所必需的营养要素。  相似文献   

Millisecond radio spikes on long centimetre and short decimetre wavelengths and occurrence frequency     

Shuchen Ji  Ruixiang Xie  Wang Min 《Astrophysics and Space Science》1992,190(1):33-41

High time-resolution data observed in two periods, respectively, by three frequencies (1.42, 2.84, and 3.67 GHz) or four frequencies (1.42, 2.00, 2.84, and 4.00 GHz) of fast sampling radiotelescopes were processed. Obtained were some significant results showing that during the obviously rising or maximum phases of solar cycle 22, the occurrence frequency of millisecond radio spikes at three or four frequencies decreased with the frequency increase and the highest occurrence frequency was at 1.42 GHz. If we assume the secondx-mode is pre-dominant in the growth rate of ECM instability, we calculate the magnetic intensity of source regions with spike bursts at the four frequencies and interpret the occurrence frequency of millisecond radio spikes on long centimetre and short decimetre wavelengths. Finally, this paper suggests that, owing to the Razing effect, whenf126 MHz the occurrence frequency of millisecond radio spikes starts to decrease.  相似文献   

NUMERICAL EXPERIMENT ON THE SEASONAL TRANSITION OF GENERAL CIRCULATION OVER ASIA - PART Ⅰ   总被引：1，自引：0，他引：1  

Ji Liren  S.Tibaldi 《大气科学进展》1984,1(1):128-149

The onset of the 1979 summer monsoon is investigated using the ECMWF grid-point model. The role of the Tibetan Plateau in this process is investigated by means of parallel model integrations with different orographies. Similarly, the relative roles of land-sea thermal contrast, latent heat release and Southern Hemisphere influence are studied. The influence of the African Highland on the onset of the Somali jet is also explored. A generally satisfactory performance of the model in representing the onset of the monsoon is documented and various contributions to this from different model components are discussed. In Pan I of this paper the impact from the Southern Hemisphere is presented.  相似文献   

Discrete element modeling of dynamic behaviors of railway ballast under cyclic loading with dilated polyhedra          下载免费PDF全文

S. Ji  S. Sun  Y. Yan 《国际地质力学数值与分析法杂志》2017,41(2):180-197

The dynamic behaviors of railway ballast under cyclic loading are simulated with discrete element method (DEM). Dilated polyhedra are constructed based on the Minkowski sum operator in order to resemble the irregular shapes of ballast particles. The polyhedral particle generation, contact detection between particles and contact laws are presented. Ballast box tests with periodic lateral boundaries are conducted to simulate the dynamics of the sleeper and ballast particles. The settlement and effective stiffness of ballast bed are investigated under cyclic loadings with five distinct frequencies. The settlement of ballast bed is significant in the first several cycles and increases with the number of cycles gradually. The higher frequency loading generates larger displacement in the same simulation time. The effective stiffness of ballast bed increases gradually. To study the effect of particles' sharpness, dilated polyhedra with different dilating radii and spherical particles are also developed. Simulation results show the sharper the ballast particles are, the smaller the produced settlement. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

Non-magnetic indicators of pedogenesis related to loess magnetic enhancement and depletion: Examples from the Czech Republic and southern Siberia     

Ondřej Bábek  Jiří Chlachula  Tomáš Matys Grygar 《Quaternary Science Reviews》2011,30(7-8):967-979

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Simultaneous observations of second and sub-second time structures in H α , radio and hard X-ray data due to the periodical particle acceleration and MHD waves in the November 1, 2004 flare     

Huang Guangli  Ji Haisheng 《Astrophysics and Space Science》2007,312(1-2):127-138

Second and sub-second structures were simultaneously detected in optical, radio and hard X-ray (HXR) band, respectively by the GanYu Station of Purple Mountain Observatory, Nobeyama Radio Observatory, and RHESSI satellite in the November 1, 2004 flare (Ji et al., in Astrophys. J. 636:L173, 2006), which may be contributed to the energy transport of the continuous heat flux from the hot corona or chromosphere evaporation and of the accelerated electrons. The linear correlations between the amplitudes of these fluctuations and their flare emissions, and those between the cross-correlation coefficients of the fluctuations at two H _α kernels, or two radio frequencies, or two X-ray energies and their flare emissions may support the causal relationship of the flare and these time structures. While, the cross-correlations of the fluctuations at three different bands suggest that the fluctuations are caused by the common thermal or nonthermal processes in the flare. Moreover, some new features of the fluctuations are reported in the flare: (1) The sub-second fluctuations in radio and HXR bands have a same timescale, which is evidently larger than that in H-alpha band. The difference may be explained by the downward movements of nonthermal electrons or the upward motion of chromosphere evaporation. (2) The power-law distributions of the amplitudes of the second and the sub-second structures are obtained at optical, radio and HXR bands with different indices. (3) The peak-to-peak correspondence of Stokes I and V components in the sub-second structures at radio band suggests that they may be resulted from a periodical particle acceleration and particle injection in this event. However, the second structures may be caused by the modulations of Alfvén waves with an upward speed of 10³ km/s.  相似文献   

1∶20万岩石化探测量碳酸盐岩分析方法研究——等离子体质谱为主的配套分析方法     

戢朝玉  李剑昌  吴列平 《岩矿测试》1998,(2)

研究了碳酸盐岩中基体元素Ｃａ和Ｍｇ对测定痕量元素的影响及消除办法，建立了用等离子体质谱法测定碳酸盐岩石中２６个痕量元素的３个分析流程；并采用Ｘ射线荧光光谱、石墨炉原子吸收光谱、原子荧光光谱等方法配套测定了碳酸盐岩石中１５种主、次量元素。配套方法的检出限、精密度、准确度均符合１∶２０万岩石化探测量碳酸盐岩分析技术指标要求。方法经标样及碳酸盐岩石样品分析验证，其结果与不同实验室、不同方法测定结果相符。  相似文献