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61.
Three types of crust exist in the area studied. There was an assembled continent at the end of the Hercynian-Indosinian cycle. Since the Cenozoic the area has shown a trend of tension, thinning and oceanization in varying degrees, which is manifested in the creeping and obduction of the Asian continent as well as the spreeding and subduction of West Pacific Ocean, thus bringing about the continental rifts, maginal basins and arc-thrence systems in this area.Geotectonic cycle usually begins with a tensional phase and ends with a compressional phase. When tension predominates, various rifts can be formed on the continental crust and the crust is in the trend of oceanization. When compression predominates, the rifts disappears, the crust is in the trend of continentization and, in the end, folded mountain belts and geosutures can be formed. Thus, the crust is tending towards "maturatity" and thickening. 相似文献
62.
用电生理学方法观察了4种不同浓度的高纯河豚毒素(tetrodotoxin,TTX)对蛙离体坐骨神经动作电位的影响.实验结果表明:1μmol/dm3TTX在给药后7 min能显著抑制动作电位的上相幅度(P<0.05),但在给药后10 min才显著抑制动作电位的下相幅度(P<0.01);20μmol/dm3TTX在给药后3 min内能完全抑制动作电位的形成.1μmol/dm3TTX在给药后1~5min对动作电位传导速度的影响没有统计学意义,5μmol/dm3TTX在5min时可显著抑制传导速度(P<0.05),而10μmol/dm3TTX在2min时便显著抑制传导速度(P<0.05).实验结果提示高纯河豚毒素对蛙离体坐骨神经动作电位的影响存在剂量效应关系. 相似文献
63.
Wave induced excess flow of momentum(WIEFM)is the averaged flow of momentum over a wave period due to wave presence,which may also be called 3-D radiation stress.In this paper,the 3-D current equations with WIEFM are derived from the averaged Navier-Stokes equations over a wave period,in which the velocity is separated into the large-scale background velocity,the wave particle velocity and the turbulent fluctuation velocity.A concept of wave fluctuating layer(WFL)is put forward,which is the vertical column from the wave trough to wave ridge.The mathematical expressions of WIEFM in WFL and below WFL are given separately.The parameterized expressions of WIEFM are set up according to the linear wave theory.The integration of WIEFM in the vertical direction equals the traditional radiation stress(namely 2-D radiation stress)given by Longuet-Higgins and Stewart. 相似文献
64.
提要应用RNeasy animal mini试剂盒抽提大黄鱼total RNA,逆转录合成模板cDNA;同时综合分析从GenBank数据库查询到已报道的转铁蛋白(Tf)基因序列,先设计并合成扩增引物扩增出大黄鱼转铁蛋白部分基因序列,再应用RACE技术,克隆出大黄鱼转铁蛋白全长cDNA基因,全长2461个核苷酸,编码661个氨基酸。应用WCG软件包,采用DNADIST和NEIGHBOR分析方法,构建了转铁蛋白系统进化树。树图显示与传统的分类地位大致相符,可以看出转铁蛋白在海水鱼和淡水鱼的进化上的差异,同时也显示大黄鱼Tf与真鲷的同源性最高。 相似文献
65.
66.
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
67.
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
68.
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
69.
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
70.
锶诱导的氧化胁迫对叉鞭金藻(Dicrateria inornata)的影响 总被引:3,自引:2,他引:3
采用不同浓度的锶胁迫方法研究了叉鞭金藻生长、叶绿素、MDA含量及三种抗氧化酶SOD、CAT、GPX活性的变化。结果表明,在实验设计的各种Sr^2 浓度内叉鞭金藻均能生长,但Sr^2 浓度较高时生长受到不同程度的抑制,细胞数量比对照组分别减少15.9%和51.0%;叉鞭金藻中叶绿素含量随着Sr^2 浓度的升高而降低,呈负相关关系;叉鞭金藻中MDA含量在较低Sr^2 浓度下稍呈下降趋势,但与对照组相比并无显著差异,而在23.04mmol/L Sr^2 浓度时是对照的1.25倍;低Sr^2 浓度时,叉鞭金藻中蛋白质含量没有大的变化,当浓度超过5.76mmol/L时则引起蛋白质含量下降;叉鞭金藻中抗氧化酶SOD在低Sr^2 时分别降低12.5%、7.5%和9.5%,高Sr^2 时显著升高,为对照组的85.7%;CAT、GPX活性在低Sr^2 浓度时差别不大,但当浓度为23.04mmol/L时升高显著,比对照组分别增加了19.8%和74.4%。 相似文献