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以中华鳖的嗜水气单胞菌纯化其外毒素,用胶体金建立斑点免疫检测方法,测定中华鳖对嗜水气单胸菌外毒素抗体效价。结果表明：该方法有高的特异性,与血清中的其它成分交叉反应小;检测灵敏度达4ng。 相似文献
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太湖流域水污染控制与生态修复的研究与战略思考 总被引：14，自引：2，他引：14
为了探明太湖水体中胶体磷含量,更深入认识营养盐在大型浅水湖泊中的循环过程和机理,分别从太湖的梅梁湾和贡湖湾两个不同类型的湖区采集水样,利用切向流超滤方法分离出胶体物质,对太湖水体中胶体磷含量进行了初步研究．结果表明:太湖水体春季胶体磷含量在0．017-0．029 mg／L间,其中梅梁湾藻型湖区胶体磷含量范围是0 023- 0．029 mg／L,贡湖湾草型湖区胶体磷含量在0．017-0．022 mg／L间．梅梁湾水体胶体磷占总磷比例平均为28．6%;而贡湖湾胶体磷占总磷比例平均达到39．3%．梅梁湾水体真溶解态磷含量显著高于贡湖湾水体,达贡湖湾的4倍．与澳大利亚的17个湖泊相比,太湖属胶体磷含量偏低的湖泊,但相对于海洋的研究结果,太湖胶体磷含量明显偏高． 相似文献
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胶体是一种分散相粒子具有特定粒径(通常为1 nm~1μm)的混合物,天然水体中的胶体通常是指水环境中普遍存在,而又符合“胶体”形态定义的物质的总和.因为具有特殊的表面性质以及独特的水动力学特点,天然水体中的胶体被认为是一种重要的污染物载体,尤其在促进重金属类的污染物迁移以及性质转化的过程中具有重要作用.本文归纳总结了水环境研究领域中胶体概念的提出与发展,讨论了现有研究中对胶体的定义与理解,比较了当前几种主要的胶体提取手段的特点.同时,针对胶体在水环境中的环境行为,详细归纳了河湖水体中胶体的物质组成、特征以及相应的检测手段,重点总结了胶体在水环境中对污染物的结合作用、胶体污染物的生物效应、胶体自身的团聚规律以及胶体对污染物迁移的影响机制.本文提出了胶体在水环境中复杂的组成成分与动态变化在胶体研究中的重要性,并对进一步揭示胶体环境效应的研究思路以及方法手段进行了展望. 相似文献
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海洋中胶体研究的新进展 总被引：11，自引：3，他引：8
对近１０年以来胶体研究的报道和进展进行综合评述。Ｃｒｏｓｓ－ｆｌｏｗ超滤技术在海洋学上的应用促进了海洋胶体的进一步研究。研究表明,胶体物质天有机碳、氮、痕量金属、放射性核素及有机污染物的生物地球化学循环中可能起着重要作用。这一领域的研究对重新认识海洋物质循环的各种过程具有深远意义。 相似文献
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Princinple of colloidal dispersion gels technologyColloidal dispersion gels are made of low concentrations of POlymer and crosslinker. Polymer concentrations normally range from 100 to 1200 ppm.In this concentration range, there is not enoughpolymer to fo… 相似文献
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Daqing Oilfield has carried out the production of polymer flooding was promoted since in 1996.Presently, polymer flooding is very successful in several production plants of Daqing Oilfield, and getting into industrialisation production. It has played a very important role in maintaining the oilfield stable production of over 50 million tons of oil.But the high permeability variation is serious, resulting in polymer production in some production wells recylingly and production concentration increasing slowly, which adversely affects polymer flooding efficiency.Colloid dispersion gels (CDG) is a unique in- depth permeability modification process. It can reduce in- depth reservoir permeability variation by moving into highly permeable, water saturated zones and providing high resistance to subsequent water injection in those zones, so that oil can be produced from tighter rock. So CDG can enlarge volumetric sweep, and improve oil recovery efficiency.We had a CDG pilot programme in Daqing Oil Field in 1999, now this pilot has been entering into effective period with produing more oil and less water.Introduction 相似文献
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Scott C. James Tanya K. Bilezikjian Constantinos V. Chrysikopoulos 《Stochastic Environmental Research and Risk Assessment (SERRA)》2005,19(4):266-279
A quasi-three-dimensional particle tracking model is developed to characterize the spatial and temporal effects of advection, molecular diffusion, Taylor dispersion, fracture wall deposition, matrix diffusion, and co-transport processes on two discrete plumes (suspended monodisperse or polydisperse colloids and dissolved contaminants) flowing through a variable aperture fracture situated in a porous medium. Contaminants travel by advection and diffusion and may sorb onto fracture walls and colloid particles, as well as diffuse into and sorb onto the surrounding porous rock matrix. A kinetic isotherm describes contaminant sorption onto colloids and sorbed contaminants assume the unique transport properties of colloids. Sorption of the contaminants that have diffused into the matrix is governed by a first-order kinetic reaction. Colloids travel by advection and diffusion and may attach onto fracture walls; however, they do not penetrate the rock matrix. A probabilistic form of the Boltzmann law describes filtration of both colloids and contaminants on fracture walls. Ensemble-averaged breakthrough curves of many fracture realizations are used to compare arrival times of colloid and contaminant plumes at the fracture outlet. Results show that the presence of colloids enhances contaminant transport (decreased residence times) while matrix diffusion and sorption onto fracture walls retard the transport of contaminants. Model simulations with the polydisperse colloids show increased effects of co-transport processes. 相似文献
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Numerical experiments are conducted to examine the effects of gravity on monodisperse and polydisperse colloid transport in water-saturated fractures with uniform aperture. Dense colloids travel in water-saturated fractures by advection and diffusion while subject to the influence of gravity. Colloids are assumed to neither attach onto the fracture walls nor penetrate the rock matrix based on the assumptions that they are inert and their size is larger than the pore size of the surrounding solid matrix. Both the size distribution of a colloid plume and colloid density are shown to be significant factors impacting their transport when gravitational forces are important. A constant-spatial-step particle-tracking code simulates colloid plumes with increasing densities transporting in water-saturated fractures while accounting for three forces acting on each particle: a deterministic advective force due to the Poiseuille flow field within the fracture, a random force caused by Brownian diffusion, and the gravitational force. Integer angles of fracture orientation with respect to the horizontal ranging from ±90° are considered: three lognormally distributed colloid plumes with mean particle size of 1 μm (averaged on a volumetric basis) and standard deviation of 0.6, 1.2 and 1.8 μm are examined. Colloid plumes are assigned densities of 1.25, 1.5, 1.75 and 2.0 g/cm3. The first four spatial moments and the first two temporal moments are estimated as functions of fracture orientation angle and colloid density. Several snapshots of colloid plumes in fractures of different orientations are presented. In all cases, larger particles tend to spread over wider sections of the fracture in the flow direction, but smaller particles can travel faster or slower than larger particles depending on fracture orientation angle. 相似文献
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大西洋中脊胶状黄铁矿的特征及其成因 总被引：1，自引：0，他引：1
大西洋中脊热液硫化物（矿床）中广泛出现松散粒状和胶状黄铁矿，利用1988年所采样品通过其形态、成份和热电性质的研究，对这种黄铁矿的成因、环带成因和热液演化特征进行初步探讨。结果表明，松散粒状和胶状黄铁矿是热液进入海底与海水混合后沉积形成，与固结粒状黄铁矿分属不同矿化阶段（期），反映热液活动的多阶段成矿特征；胶状黄铁矿环带和微环带是黄铁矿胶体沉淀后重结晶作用形成的；松散粒状黄铁矿和胶状黄铁矿同时出现是已经停止活动的烟囱物特征。 相似文献