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三株光合细菌应用于对虾饲料及其养殖效果 总被引：4，自引：0，他引：4
光合细菌（ＰｈｏｔｏｓｙｎｔｈｅｔｉｃＢａｃｔｅｒｉａ简称ＰＳＢ）作为一类能充分利用光能和各种低分子有机物生长繁殖的微生物，由于其独特的生理功能和菌体内所含的丰富营养，已引起环保、水产及其有关部门的广泛重视。为了进一步探讨光合细菌在水产养殖中的作用，我们在１９８７～１９８９年对沼泽红假单胞菌（Ｒｈｏｄｏｐｓｅｕｄｏｍｏｎａｓｐａｌｕｓｔｒｉｓ）在中国对虾饲料和脊尾白虾、中国对虾育苗中的作用进行初步探讨的基础上，又进一步分离了球形红假单胞菌Ｒ．ｓｐｈａｅｒｏｉｄｅｓ和荚膜红假单胞菌Ｒ．ｃａｐｓｕｃ… 相似文献
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研究了闽南－台湾浅滩上升流区海洋拮抗菌的生态分布、种类组成及其抗 菌活性。结果表明：在该海区海水中桔抗菌占总异养菌数的１．２～９．４％，沉积物中 则占４．３～１５．６％；拮抗菌的分布具有明显的季节变化，夏季桔抗菌的丰度大于其 他季节，属的组成也较复杂多样。在所分离的桔抗菌中，有６株桔抗菌对多种试验 菌株有不同程度的抑制能力，被鉴定为假单胞菌属（Ｐｓｅｕｄｏｍｏｎａｓ）、孤菌属（Ｖｉｂｒｏ）、 黄杆菌属（Ｆｌａｖｏｂａｃｔｅｒｉｕｍ）和无色杆菌属（Ａｃｈｒｏｍｏｂａｃｔｅｒ）。作者讨论了海洋桔抗菌的 时空分布与环境因子的关系及其在海洋环境自净中的作用，阐述了开发、利用海洋 微生物资源的重要性。 相似文献
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海洋光合细菌的分离鉴定及其生长条件的研究 总被引：5，自引：0，他引：5
用红色硫细菌培养基从青岛沿海潮间带海泥中分离出8株光合细菌,经鉴定菌株HD_1属最小着色菌(Chromatium minutissimum),HD_2、HD_4为细着色菌(Chromatium gracile);菌株SL_1、SL_1x、PL_1和PL_2为嗜酸红假单胞菌(Rhodopseudomonas acidophila),菌株HCx为沼泽红假单胞菌(Rhodopseudomonaspalustris)。分离菌株均具运动性,不需生长因子。菌株HD_1、HD_2和HD_4在厌氧光照条件下利用硫化物,且在细胞内贮存硫粒。菌株HD_1、HD_2的最适盐度为4.0％,最适pH为7.0,8.0。当培养基中硫化物含量为0.01—0.04％时,菌株HD_1、HD_4生长良好。菌株PL_2在初始pH为6时生长最好。酵母膏对菌株HCx具有明显的促生长作用。 相似文献
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渤海南部S3孔晚第四纪海相地层的划分及环境演变 总被引：31，自引：0，他引：31
根据微体化石、粒度、孢粉、粘土矿物和碳酸钙含量等多项分析资料,以及古地磁、１４Ｃ和ＥＳＲ等项测年资料,划分出７个海相地层,它们是：中更新世中、晚期的Ｈ７（４１７．０～４６０．０ｋａＢ．Ｐ．）和Ｈ６（１５７．５～２３１．３ｋａＢ．Ｐ．）海相层;晚更新世前半期末次间冰期的Ｈ５（１００．６～１２４．３ｋａＢ．Ｐ．）和Ｈ４（７６．５～８７．６ｋａＢ．Ｐ．）海相层,末次冰期里两间冰阶的Ｈ３（５８．２～６７．４ｋａＢ．Ｐ．）和Ｈ２（２８～３６ｋａＢ．Ｐ．）海相层,以及冰后期的Ｈ１（８．５ｋａＢ．Ｐ．以来）海相层。其中Ｈ７为渤海海底最新确定的年代最老的海相层。以Ｓ３孔为主,与渤海中部的ＢＣ－１孔和西部的辛集孔对比,阐明了渤海晚第四纪海侵海退古环境演变历史 相似文献
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螺旋藻多糖对CD3AK细胞增殖能力的影响 总被引：7，自引：0，他引：7
研究了螺旋藻多糖（ＰＳ）对ＣＤ３ＭｃＡｂ激活的杀伤细胞（ＣＤ３ＭｃＡｂ Ａｃｔｉｖａｔｅｄ Ｋｉｌｌｅｒ Ｃｅｌｌｓ,ＣＤ３ＡＫ Ｃｅｌｌｓ）增殖能力的影响。结果表明,当ＰＳ浓度为２．５μｇ·ｍｌ＾－１培养体系条件下,对ＣＤ３ＡＫ细胞具有明显的刺激细胞增殖作用（Ｐ〈０．０２）;对培养长达２３ｄ的ＣＤ３ＡＫ细胞杀伤肿瘤细胞（Ｋ５６２细胞）的活性仍维持在较高的水平（４６．５％￣５０％）。提示ＰＳ对辐射 相似文献
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条斑紫菜对无机碳的利用 总被引：4，自引：0，他引：4
于１９９８年３月在青岛太平角采集条斑紫菜,在室内光照强度为１２０μＥ／（ｍ~２·ｓ）的培养架上培养,通过测定其光合作用引起密闭海水体系ｐＨ值及无机碳浓度的变化,借助于各种无机碳利用的抑制剂（Ａｚ、Ｖａｎ、ＤＩＤＳ、ＳＩＴＳ）对其无机碳利用机制进行了研究。结果表明,（１）条斑紫菜可间接吸收ＨＣＯ~（－）_（３）。胞外碳酸醉酶（ＣＡ）催化ＨＣＯ~（－）_（３）水解成ＣＯ_２扩散进入胞内是条斑紫菜无机碳利用的主要形式,占全部无机碳利用的７３％以上。Ａｚ是胞外ＣＡ的抑制剂,可直接检测胞外ＣＡ的存在,它不能透过细胞膜。（２）条斑紫菜可依赖于细胞膜上ＡＴＰ酶对ＨＣＯ~（－）_（３）直接转运。但未发现带Ⅲ蛋白（ｂａｎｄ ３ Ｐｒｏｔｅｉｎ）及 Ｎａ~＋／ＨＣＯ_（３）~（－）协同转运系统的参与。（３）条斑紫菜ｐＨ值补偿点为９．８３,ＣＯ_２补偿点为０．０４μｍｏｌ／Ｌ。 相似文献
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阐述把维生素Ｂ１２生产菌添加到培养水中培养褶皱臂尾轮虫ＢｒａｃｈｉｏｎｕｓＰｌｉｃａｔｉｌｉｓ的买验。共１８株细菌分离于轮虫培养池，其中，有一株产维生素Ｂ１２的假单胞杆菌ＴＰ４对轮虫的生长繁殖有明显的促进作用。把ＴＰ４菌株培养后，加入到２Ｌ的烧杯和５００Ｌ的水槽中培养泰国Ｓ型轮虫时．在９ｄ（天）和６ｄ（天）中，轮虫密度从１２４～１３９和２４２～２８８个体／ｍｌ增殖到４，４１７～５，５４０和１，０１７～１，２５４个体／ｍｌ，分别比对照组增加了４～６及２～３倍。 相似文献
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南黄海浮游植物与水色透明度之间相关关系的研究 总被引：1，自引：0，他引：1
本文根据 １９９５ 年 ９ 月在南黄海获取的资料,分析和讨论了该水域浮游植物现存量（叶绿素 ａ （ Ｃ Ｈ ））、初级生产力（ Ｐ Ｐ） 和海水光学参数（透明度（ Ｓ Ｔ））、水色（ Ｗ Ｃ）） 之间的相关关系。分析结果表明,夏末秋初南黄海 Ｃ Ｈ 与 Ｐ Ｐ, Ｃ Ｈ 与 Ｗ Ｃ 和 Ｐ Ｐ 与 Ｗ Ｃ 以及悬浮物（ Ｓ Ｓ） 与 Ｗ Ｃ 之间均有良好的正相关关系。相关式分别为： Ｐ Ｐ ＝ ２２５１９ｌｎ（ Ｃ Ｈ ） ＋ ４８８９１ 或 Ｐ Ｐ ＝ ５ Ｅ－ ０５ Ｃ Ｈ １６４６４（ Ｒ２ ＝ ０７０３７）; Ｗ Ｃ ＝ ４０３ｌｎ（ Ｃ Ｈ ） ＋ ８９７６８ 或 Ｗ Ｃ ＝ ７１３０６ Ｃ Ｈ ０４７４７ （ Ｒ２ ＝０７９２１）; Ｃ Ｈ ＝ １５４３７ｌｎ（ Ｓ Ｓ） ＋ １３６４７ 或 Ｃ Ｈ ＝ ０７４９９ Ｓ Ｓ１２５２（ Ｒ２ ＝ ０７２２３）; Ｐ Ｐ ＝３３２８６ｌｎ Ｓ Ｓ＋ １５２２２ 或 Ｐ Ｐ ＝ ３３０２９ Ｓ Ｓ０５６９４ （ Ｒ２ ＝ ０５４７６）; Ｐ Ｐ ＝ ４２５８８ｌｎ（ Ｗ Ｃ） － ３７０７１或 Ｐ Ｐ ＝ ６６５１２ Ｗ Ｃ０８６６５（ Ｒ２ ＝ ０６７３１） 以 及 Ｓ Ｓ ＝ １４０１９ｌｎ（ Ｗ Ｃ） － １３３６３ 相似文献
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研究ＳｅｐｈａｄｅｘＧ－２５，Ｇ－５０，Ｇ－１００，Ｇ－２００和Ｇ－２００（超细）等型号的葡聚糖凝胶系统，对溶解在１．０％，ＳＤＳ－２Ｍｅ水溶液中的网纹藤壶Ｂａｌａｎｕｓｒｅｔｉｃｕｌａｔｕｓ固态胶蛋白组分的分离制备效果，结果表明，ＳｅｐｈａｄｅｘＧ－２００和Ｇ－２００（超细）两种葡聚糖凝胶层析柱（直径１．７ｃｍ，长３０ｃｍ）用０．０５ｍｏｌ．Ｌ＾－１Ｔｒｉｓ－ＨＣｌ－１％ＳＤＳ－２Ｍｅ溶液洗脱时 相似文献
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Chandralata Raghukumar G. Sheelu P. A. Loka Bharathi Shanta Nair C. Mohandass 《Marine Georesources & Geotechnology》2001,19(1):1-16
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance. 相似文献
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Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
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Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm. 相似文献
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海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。 相似文献
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Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
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Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations. 相似文献
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The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans 总被引：1，自引：0，他引：1
A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria （ 〉 99% ）, but also between polar marine bacteria and bacteria from other aquatic environments （ ≥ 98.8% ）, including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level. 相似文献