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1.
利用高气压强电离放电方法制取高比值浓度的羟基溶液,应用于压载水外来有害生物入侵性传播,赤潮生物污染等领域的防治。论文详细介绍了羟基产生的等离子体过程,在进行的20t/h压载水中试试验和杀灭赤潮微生物的围隔实验中,微生物致死率分别达到100%和99.89%,并且在很大程度上改善了海水水质。结果表明羟基是治理海洋有害生物污染行之有效的方法。  相似文献   

2.
采用强电场电离H2O、O2方法,在分子层次上加工成高浓度羟基自由基(OH.)溶液,喷洒在有赤潮生物的海面上,当海水的羟基质量浓度达到0.68 mg/L时,致死洛氏角刺藻(Chaetoceros lorenzianus)等31种赤潮生物效率达到99.89%,致死细菌、弧菌效率达到100%,致死膝沟藻孢囊、多甲藻孢囊效率达到100%;赤潮生物叶绿素a含量低于检测方法低限值;剩余OH.分解成H2O和O2;尸体将分解成CO2、H2O和微量无机盐。从试验数据表明,OH.是治理赤潮有效可行的绿色新方法。实现了治理赤潮以及加工羟基过程的零污染、零废物排放、零残留物。  相似文献   

3.
羟基游离基杀死压载水中微生物研究   总被引:9,自引:0,他引:9       下载免费PDF全文
利用介质阻挡强电离放电的方法,将空气中的O2和海水中H2O电离离解成OH等氧化自由基,溶于海水中形成高浓度羟基药剂。羟基致死压载水中入侵的细菌、微藻生物的反应属于游离基反应,具有广谱致死特性,在压载水外排(或输入)过程中就可致死入侵微生物,不存在药剂污染海洋环境等问题。实验室研究结果表明:致死微生物的羟基阚值为O.8mg/L。  相似文献   

4.
模拟压载水排放过程,以球等鞭金藻为实验对象,进行了羟基处理20t/h压载水的中试实验。在高气压强电场作用下,将O2,H2O电离离解成OH^*等强氧化自由基,在分子层次上加工高浓度羟基等自由基溶液,泵入压载水主管道进行在线治理。实验结果表明羟基溶液在比值浓度为0.55mg/L时,在很短的排放管道中,就可以有效地抑制和杀死球等鞭金藻,分解叶绿素、氨基酸等。  相似文献   

5.
甲藻赤潮与水体中营养盐的关系初探   总被引:8,自引:0,他引:8  
林昱 《台湾海峡》2001,20(1):77-79
作者在国家海洋局第三海洋研究所的陆基水池中,应用围隔实验技术,排除了水动力、盐度等环境因子的变动性的干扰,人工诱发甲藻赤潮.在这个围隔实验的两个围隔体中,分别发生了一种裸甲藻(Gymnodinium sp.)和海洋原甲藻(Prorocentum micans)的赤潮.在赤潮发生和发展过程中所监测到的营养盐数据表明有些甲藻增殖不一定需要水体中高营养盐;营养盐供给的多寡会导致甲藻赤潮优势种的差异和赤潮规模.  相似文献   

6.
厦门西港引发有害硅藻水华磷的阈值研究   总被引:12,自引:1,他引:11  
林昱  林荣澄 《海洋与湖沼》1999,30(4):391-396
1995年10月,在厦门市国家海洋局第三海洋研究所的陆基水池中,应用海洋围隔生态系实验技术,研究了在无海流、盐度等因子干扰的情况下,磷的形态、分布及其与浮游植物生物量的相关性。结果表明,海水中的可溶性无机磷(DIP)随时间里指数函数减少。浮游植物生物量主要与可溶性无机磷密切相关:[Chl-a]=A×e-B[PO4],这种相关的浮游植物生物量表现2d左右的滞后现象。还探讨了限制浮游植物增殖的DIP的最低浓度为0.3-04μmol/L,从DIP表现浓度估算浮游植物可能达到的最大生物量为[Chl-a]=10mg/m3,并由此估算出引发中肋骨条藻赤潮的DIP的阈值为1.2μmol/L,作为赤潮预测预报的参考。  相似文献   

7.
通过现场围隔实验,模拟赤潮发生过程,研究了种群不同生长阶段中不同粒级浮游植物种群的变化情况。结果表明,添加营养盐能有效促进浮游植物的生长,东海原甲藻围隔(M1)和自然水体围隔(M2)中浮游植物分别于第7天和第4天出现生长高峰,叶绿素a最大值分别为112.79mg/m和235.60mg/m。微型浮游植物与微微型浮游植物存在竞争,微型对微微型生长的抑制作用:M2〉M1。在营养盐丰富时,硅藻的增殖速率比东海原甲藻快,达到高峰期时间短,消亡也快。硅的减少促进硅藻水华的消亡。  相似文献   

8.
于1992年9-12月,使用中尺度围隔装置(1.7m^3)研究扰动的水体对赤潮浮游植物种类演替的影响。实验结果表明,对富营养化的围隔水体进行扰动可以改变水体中赤潮生物的演替次序,即甲藻和鞭行藻往往出现在硅藻赤潮之后,本文从另一方面证明,富营养下的相对稳定水体有助于鞭毛藻类赤潮的形成。  相似文献   

9.
本文对2018年6月10?14日在泉州湾海域发生的一次链状裸甲藻(Gymnodinium catenatum)赤潮的消亡过程进行研究。在现场跟踪监测,共设置4个站位,进行6个航次海洋环境及浮游植物的调查。结合本文对泉州湾海域甲藻包囊的调查研究,探索休眠包囊与赤潮生消过程的关系。研究结果显示,赤潮发生时海况良好,水温和盐度分别介于27.1~28.2℃和29.7~31.4之间,活性磷酸盐和无机氮浓度分别介于未检出至0.045 4 mg/L和0.050~0.281 mg/L之间,赤潮生物密度与营养盐浓度没有呈现显著的相关关系,大风大浪是导致赤潮消亡的重要原因;赤潮消亡过程中共鉴定出浮游植物3门48属100种,硅藻门种类最多;赤潮消亡期间浮游植物群落结构发生变化,前期链状裸甲藻占绝对优势,最高密度达(7.02±0.11)×106 cells/L,后期中肋骨条藻(Skeletonema costatum)和旋链角毛藻(Chaetoceros curvisetus)代替链状裸甲藻成为优势种,且浮游植物种类数明显增加;同时在泉州湾海域共鉴定甲藻包囊5大类37种和1种未定种,平均丰度为574 cysts/g,以异养型甲藻包囊为主;休眠包囊在赤潮生消过程中起着重要作用,赤潮消亡时形成休眠包囊,包囊数量会随着时间呈下降趋势,但仍有萌发的可能,具有重新暴发赤潮的潜在性,需要引起重视。  相似文献   

10.
一种提高粘土矿物去除赤潮生物能力的新方法   总被引:36,自引:7,他引:36  
在研究粘土颗粒与赤潮生物絮凝作用的基础上,建立了粘土表面改性对其絮凝作用影响的理论模型,认为改变粘土颗粒的表面性质提高其去除赤潮生物能力的主要途径,提出在粘土中引入PACS(聚羟基氯化铝)的改性方法。结果表明,对于微型原甲藻(Proro-centrum minimun)体系,粘土中引入微量PACS后,其去除率达90%以上的高岭土用量由原来的2g/L降至0.1g/L,去除效率提高近20倍。考察了PA  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
17.
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   

18.
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   

19.
20.
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   

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