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21.
海水网箱养殖石斑鱼病原菌研究   总被引:12,自引:0,他引:12  
从网箱养殖的石斑Epinephyelussp.中分离出一种致病菌——创伤弧菌Vibriovulnificus。本文报道该病原菌的分离、形态、毒力、生理生化特性。该菌毒力较强,感染死亡率可达80%以上。  相似文献   
22.
西沙群岛造礁石珊瑚群落结构的再分析   总被引:3,自引:1,他引:3  
邹仁林 《海洋学报》1980,2(3):98-110
近几年来,我们多次对西沙群岛珊瑚礁作了生态调查,对西沙群岛的岛、礁有了一定的认识,对造礁石珊瑚群落结构也进行了概括的报导[1],为了进一步认识和了解西沙群岛,我们又于1976年4—5月选择处于西沙群岛西南隅的沙岛——中建岛,和位于西沙群岛东北面绿树成林的赵树岛作重点解剖,对造礁石珊瑚群落结构做了进一步的分析,以期为发展和利用珊瑚礁做一点有用的工作。  相似文献   
23.
I~IOW~ne nelnatode is a ban gIOup of benthic OrgAnsrns. Abbot 5 000 spotes Of free-livingnelnatedes have ben dedbo so far, and it has ho estimated that abbot 20 (XX) are as yetunknoWn. Chinese bothologist has Paid attention to marine nelnatodes in China seas in yare. The spatial distribution and shoes commotion of marine nelnatedes in the HUanghe EstUary, Qinhuangdao waters, QingdaO Bay and Xiamen ~ have ho reported (Zhang etal., 1990, 1991, 1993; ac and Li, 1998). ~ new shoes in the…  相似文献   
24.
爆破、矿震与地震的波谱差异   总被引:7,自引:3,他引:7  
根据辽宁数字地震台网记录的爆破、矿震与地震的数字资料,采用波谱分析的方法,选取4个台站对其所在区域182个爆破、矿震与地震事件的记录,对比研究波谱特征,发现爆破、矿震与地震的纵横波拐角频率fc(P,S)及最大谱值等存在的差异。  相似文献   
25.
Brightness temperature is a main index to reflect the energy of microwave radiation of an object. Using lunar brightness temperature data, physical properties of lunar regolith, such as thickness, heat flow and dielectric permittivity, could be interpreted. There are two methods to study brightness temperature distribution of the moon: the first is used to measure lunar brightness temperature by radio observation or spaceborne microwave radiometers, and the second is used to simulate calculation by the physical model. On the basis of the measurements of lunar brightness temperature in the history, this study analyzed the main physical model of lunar brightness temperature, also including its theory and influence factors. The authors concluded that surface and subsurface temperatures of the moon, dielectric properties and layered structure of lunar regolith were the main factors affecting the global brightness temperature of the moon. These factors should be quantified in detail in the future research.  相似文献   
26.
2020年,长江三峡地区年平均气温17.2℃,接近常年;年平均降水量1530.8毫米,偏多29%,为1961年以来第二多,仅次于1998年.6月,7月降水量及年平均暴雨日数均为1961年以来第二多.平均风速较常年偏大;相对湿度略偏高;各月均无酸雨出现,近十余年酸雨强度呈现明显减弱趋势.2020年,三峡地区夏季暴雨洪涝灾...  相似文献   
27.
The relationship of N2O distributions with the Arctic vortex breakup is first analyzed with a probability distribution function (PDF) analysis. The N2O concentration shows different distributions between the early and late vortex breakup years. In the early breakup years, the N2O concentration shows low values and large dispersions after the vortex breakup, which is related to the inhomogeneity in the vertical advection in the middle and high latitude lower stratosphere. The horizontal diffusion coefficient (Kyy) shows a larger value accordingly. In the late breakup years, the N2O concentration shows high values and more uniform distributions than in the early years after the vortex breakup, with a smaller vertical advection and Kyy after the vortex breakup. It is found that the N2O distributions are largely affected by the Arctic vortex breakup time but the dynamically defined vortex breakup time is not the only factor.  相似文献   
28.
In a previous paper (Hou et al. in Celest Mech Dyn Astron 119:119–142, 2014a), the problem of dynamical symmetry between two Jupiter triangular libration points (TLPs) with Saturn’s perturbation in the present configuration of the two planets was studied. A small short-time scale spatial asymmetry exists but gradually disappears with the time going, so the planar stable regions around the two Jupiter TLPs should be dynamically symmetric from a longtime perspective. In this paper, the symmetry problem is studied when the two planets are in migration. Several mechanisms that can cause asymmetries are discussed. Studies show that three important ones are the large short-time scale spatial asymmetry when Jupiter and Saturn are in resonance, the changing orbits of Jupiter and Saturn in the planet migration process, and the chaotic nature of Trojan orbits during the planet migration process. Their joint effects can cause an observable difference to the two Jupiter Trojan swarms. The thermal Yarkovsky effect is also found to be able to cause dynamical differences to the two TLPs, but generally they are too small to be practically observed.  相似文献   
29.
30.
Coagulation of red tide organism cells with clays is discussed in theory and the effects of some fac-tors on it are studied.A quantitative model is presented which describes how the coagulation varies withpH in solution.According to the model,within the pH-range between pH_(zpc_a)and pH_(zpc_b),V_R is negativeand the coagulation is strong and strongest at pH=(pH_(zpc_a)+pH_(zpc_b))/2.It is also demonstrated that whenthe diameter of clay particles is close to that of cells,the collision probability is low,resulting in weakercoagulation.The model results have been corroborated by experiments and so are scientific and theoreticalbases for application.  相似文献   
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