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211.
In the light of the sea level synoptic charts from July to August for 1975-1978, we obtained more observed records of low latitudes by using the analysed stream and temperature-moisture field (or so called energy field θe field and θse field), the main characteristics of these fields in the period of multi-typhoon genesis and of typhoon interval in the mid-summer are studied.Finally, it should be pointed out that the position of the typhoon genesis and the typhoon track are generally consistent with the low temperature-moisture region of the sea surface as well as with its tendency, so that a valuable information is obtained for the forecast of the typhoon track. 相似文献
212.
This paper discusses the geochemical characteristics of the interstitial water of the Bohai Gulf, where the main salt contents (K+, Na+, Ca++ Mg+ + , C1-, HCO3-, SO4-) in 55 sedimentary layers of 13 cores (3-4 m in length) and those of bottom seawater have been determined and the exchange capacity and exchange cations (K+, Na+, Ca++, Mg++) of the layers analysed (see Fig. 1)Fig. J. The stations of core samplings in the Bohai Gult. 相似文献
213.
In seven cruises on benthic organisms in the nearshore waters(>50 m) to the west of the Taiwan Strait(23°20''-25°54''N,117°11''-119°58''E) in 1961-1964,altogether 189 stations of quantitative grabbing and 33 stations of qualitative trawling were made.
Altogether 392 species of benthic organisms have been identified.The composition was dominated by nearshore shallow water species,with tropical and subtropical species absolutely dominant.The total average of biomass was 38.0 g/m2 and average density,116.0 ind./m2.The communities of benthic organisms in the area can be classified into five communities namely,(1) Amphiura sp.-Acaudina molpadioides Community;(2) Protankyra asymmetrica-Arnphioplus pracstans-Murex trapa Community;(3) Modiolus meicalfei-Phyllophorus liuwutiensis-Armandia letocirris-Nephtys sinensis Community;(4) Branchiostoma belcheri-Solenr oseomaculatus-Marphysa sinensis- Onuphis eremita Community;(5) Iconomtra japonica-Barbatia decussata Community. 相似文献
Altogether 392 species of benthic organisms have been identified.The composition was dominated by nearshore shallow water species,with tropical and subtropical species absolutely dominant.The total average of biomass was 38.0 g/m2 and average density,116.0 ind./m2.The communities of benthic organisms in the area can be classified into five communities namely,(1) Amphiura sp.-Acaudina molpadioides Community;(2) Protankyra asymmetrica-Arnphioplus pracstans-Murex trapa Community;(3) Modiolus meicalfei-Phyllophorus liuwutiensis-Armandia letocirris-Nephtys sinensis Community;(4) Branchiostoma belcheri-Solenr oseomaculatus-Marphysa sinensis- Onuphis eremita Community;(5) Iconomtra japonica-Barbatia decussata Community. 相似文献
214.
Marine biological choruses observed in Xiamen harbour from August 1981 to October 1982 lasted for a few hours each time during the neap tide in spring, summer and autumn, in both the evening and the morning, with molt energy at frequencies between 700 Hz and 1.6 kHz and spectral peaks mainly at 800 Hz, 1 kHz and 1.25 kHz. During choruses, noise spectrum levels rose up to 46 dB higher than the background noise in the sea Mate 0. The statistics of occurrence of the evening choruses indicate that they might be fairly widespread in and near shallow waters of the region. Sources of such choruses are likely to be attributed to Johnnius belengerii and Collichthys lucidut of the family Sciaenidae. 相似文献
215.
Monthly and seasonal panel experiments were carried out in the Yongxing Island from September 1979 to August 1981. Altogether 119 species of fouling organisms are collected, of which, Hydroides elegans, Serpula vermicular is, Scrupocellaria longispinosa, Amathia distant, Enteromorpha spp. and Ostrea spp. are dominant species. Fouling of organisms may occur all the year round with evident seasonal variations, Species succession in the process of community formation is very evident and the climax has arrived after two years. Great variation exists between fouling organisms in different years and at different stations. 相似文献
216.
鳗弧菌(Vibrio anguillarum)M3菌株生长条件及其对蛋白酶产量的影响 总被引:2,自引:5,他引:2
采用体外测定细菌浓度、胞外产物(ECP)蛋白含量和蛋白酶活力的方法,进行了鳗弧菌M3菌株在2216E培养基中的培养条件研究。结果表明,该菌株用固体培养基培养至24h左右,可得到较高的菌体浓度、ECP蛋白含量和蛋白酶活力。采用响应面分析方法设计实验,用SAS统计软件分析数据,得到NaCl浓度、pH值和温度对菌体生长及蛋白酶产量影响的回归模型。在2216E培养基的基础上,添加不同氮源、碳源物质以及不同浓度蛋白胨进行生长研究。结果表明,胰大豆蛋白胨能促进菌体生长及ECP蛋白分泌;NH4Cl与酪蛋白水解物可抑制蛋白酶的产生;牙鲆肌肉匀浆对菌体、ECP蛋白产量和蛋白酶产生有不同程度的促进作用;培养基中蛋白胨浓度为4%时菌体量与ECP蛋白含量达最高值,在蛋白胨浓度为2%时蛋白酶分泌量已稳定;1%的葡萄糖、蔗糖、甘油均能显著地提高菌体及ECP蛋白产量,却抑制了蛋白酶的产生。 相似文献
217.
Scaling analysis of deposition from turbidity currents 总被引:3,自引:0,他引:3
Many oil-bearing sedimentary deposits are formed by the settling of particles from turbidity currents. Modeling sedimentary processes that form these turbidites enables the calculation of properties such as extent, depth, porosity and permeability of hydrocarbon-bearing reservoirs. This paper estimates the extent and thickness of turbidites from the initial conditions of the turbidity flow. This is achieved by the application of scaling analysis of the partial differential equations that govern the dynamics of and deposition from turbidity currents. We apply the results of scaling analysis to five modern submarine fans. The predicted and actual values of the dimensions of the fan deposits match well. We then compare the derived results against tabulated sizes of ancient turbidites. The comparisons are good as long as we correctly identify the flow regimes in which the deposition took place. The good agreements observed in the two cases show that the estimates obtained using scaling analysis can provide useful first-guess values for the dimensions of the deposits. 相似文献
218.
The colony-forming Phaeocystis species are causative agents of dense bloom occurrences in coastal waters worldwide. It is difficult to separate them because of the different morphologies associated with their colonial stages. In this study we applied molecular approaches to analyze the genetic variation of Phaeocystis globosa and Phaeocystis pouchetii from several geographic regions, and to assist in tracing the dispersal of bloom-forming Phaeocystis species in coastal waters of China. The sequences of the internal transcribed spacers (ITS1 and ITS2) of rDNA and the 5.8S ribosomal RNA gene of Phaeocystis strains were determined. Sequence comparison shows that P.globosa was the most divergent to P. pouchetii, exhibiting sequence divergence higher than 0.08. However, lower genetic divergences existed between strains of P.globosa. The sequence comparison of the Phaeocystis rDNA ITS clearly shows that the species isolated from the southeast coast of China is identified as P.globosa rather than P. cf. pouchetii or other species. Furthermore, the significance of rDNA variation in distinct global populations of P.globosa suggested it might have had sufficient time to accumulate detectable mutations at the rDNA locus, supporting the hypothesis of ancient dispersal of P.globosa to many areas, meaning that P.globosa blooms in the coastal waters of China are endemic rather than a newly introduced species or a foreign source. Finally, based on the high divergent region of rDNA ITS, a pair of species-specific primers for P.globosa were designed, they could be useful to detect the presence of this species in mixed plankton assemblages or flagellate stages that are recognized with diffculties by means of conventional microscopy. 相似文献
219.
介绍了斜坡式防波堤砌石护面中的插砌条石和干砌块石在波浪作用下的力学图式及作用机理 ,重点给出考虑摩擦力作用时的砌石块体稳定厚度的计算公式 ,并结合工程实例验证了公式的适用性 相似文献
220.
结合近年来参与有关水下工程检测和项目监理的实践体验 ,从总结水下工程项目的基本特征着手 ,分析了水下工程项目监理的主要任务 ,并结合对于实施水下工程项目监理必备装备条件的探讨 ,介绍了国内外现有水下监测技术装备的开发应用状况 相似文献