Similarity Scaling Of Surface-Released Smoke Plumes

Concentration fluctuation data from surface-layer released smokeplumes have been investigated with the purpose of finding suitable scaling parametersfor the corresponding two-particle, relative diffusion process.Dispersion properties have been measured at downwind ranges between 0.1 and 1 km from a continuous, neutrally buoyant ground level source. A combinationof SF₆ and chemical smoke (aerosols) was used as tracer. Instantaneous crosswind concentration profiles of high temporal (up to 55 Hz) and spatialresolution (down to 0.375 m) were obtained from aerosol-backscatter Lidar detectionin combination with simultaneous gas chromatograph (SF₆) reference measurements. The database includes detailed crosswind concentration fluctuation measurements. Each experiment, typically of 1/2-hour duration, containsplume mean and variance concentration profiles, intermittency profiles andexceedence and duration statistics. The diffusion experiments were accompanied by detailed in-situ micrometeorological mean and turbulence measurements. In this paper, a new distance-neighbour function for surface-released smoke plumes is proposed, accompanied by experimental evidence in its support. The new distance-neighbour function is found to scale with the surface-layer friction velocity,and not with the inertial subrange dissipation rate, over the range of distance-neighbour separations considered.     

聚合物驱油浓度与粘度的研究

本文对聚全物驱油试验获得聚合物溶液的方式和聚合物浓度、粘度的测定进行了研究和比较，得到了辉锐公司自动混配装置中的可编程控制器设置浓度的修正值。此研究对控制聚合物浓度稳定、准确地注入和聚合物驱油效果的评价具有实际价值。     

Experimental study on three dimensional movements of particles Ⅰ Effects of particle diameter on velocity and concentration distributions

Based on the three Dimensional Particle Tracking Velocimetry （3D PTV） system, the characteristics of motion of particles with four different diameters were investigated under the steady flow conditions The longitudinal average velocity profiles of these particles were in accordance with Log-law, while the vertical and transverse velocities remained very low with minimal fluctuation. The time-average velocity of particles in the bed load layer was 8.50u., close to Bagnold＇s assumptionUn -60. The vertical concentration distribution of particles in the suspension region agreed with the Rouse equation. When the diameter of particles was relatively large, there existed an evident concentration gradient in the bed load layer.     

Sorption Preconcentration and Determination of Cobalt in Industrial Solutions by Diffuse Reflection Spectroscopy Method

Cobalt and its compounds have a broad field of application in Russian industries, being essential raw materials for metallurgy, medicine, and agriculture. That is why the production of cobalt is one of the key industries in Russia. Cobalt is produced from mineral raw materials as well as from secondary raw materials (for example, after processing of spent catalysts of oil refinery). It can also be obtained as a by‐product of nickel, manganese, and some other metals processing. That is the reason why the solutions of Ni and Mn industries contain up to 50 g/L of cobalt. obalt compounds are harmful for men’s heart, bloodvessel system, and thyroid gland. This fact explains the importance of the monitoring of cobalt concentrations in natural water and sewages. This task can be effectively achieved using the analytical sorption technique. The present work is focused on the preconcentration of cobalt and its determination by means of diffuse reflection spectroscopy. The preconcentration of cobalt was carried out using the macronetwork cation exchangers KB‐2M and KB‐2‐3T synthesized on the basis of methyl acrylate and long‐chain cross‐linking agents copolymers. Based on these collectors, a cobalt determination method in industrial solutions was worked out using solid‐phase spectroscopy. The colored surface compound to be determined was obtained by a preceding cobalt sorption on the resin and by subsequent treatment of the concentrate obtained with definite amount of nitroso‐R‐salt. The Co calibration curve is linear in the concentration range of 0.05...0.50 mg/L Co (sample volume is 50.0 mL) and the detection limit is 0.02 mg/L (1 μg absolute).     

彝良-镇雄铅锌矿矿集区资源潜力分析

矿集区构造、地层、遥感数据等控矿因素结合统计和分析,建立地质综合信息数学信息模型,并据此确定信息量边界值,在矿集区内圈定3个找矿有利靶区,一个A级两个B级。     

Factors Controlling Total Concentration and Aqueous Speciation of Aluminium in an Acidic Headwater Stream of the Bavarian Forest National Park: a Modelling Approach

The purpose of the present paper is to analyse factors controlling total concentration and aqueous speciation of aluminium in the Große Ohe River, using a thermodynamic equilibrium model and a mixing approach. A model compound for humic substances is derived on the basis of the relation between anion deficit and the organic carbon content in the river as well as literature data. An equilibrium speciation model for aluminium is set up, considering this model compound and relevant inorganic solutes. Although the model cannot be verified directly, its results may be viewed as qualitatively correct. Applying the model to measured stream water samples highlights that aqueous speciation of aluminium is mainly controlled by the pH value and discharge and that free aluminium concentrations reach clearly toxic levels during acidic episodes. Comparing measured concentrations of sulfate and H⁺ and calculated concentrations of Al³⁺ with solubility curves of gibbsite like minerals and jurbanite clearly shows that total aluminium concentrations are not controlled by equilibria with these mineral phases alone. The observed relationship can be better explained from a mixture of two distinct waters, representing lowflow and highflow chemistry, and the resulting equilibrium concentrations. This indicates that total aluminium concentration, in particular during high discharge events, is mainly controlled by the mixture of waters with differing chemistry and flowpaths.     

Extension of a fluctuating plume model of tracer dispersion to a sheared boundary layer and to a large array of obstacles

Fluctuating plume models provide a useful conceptual paradigm in the understanding of plume dispersion in a turbulent flow. In particular, these models have enabled analytical predictions of higher-order concentration moments, and the form of the one-point concentration probability density function (PDF). In this paper, we extend the traditional formalism of these models, grounded in the theory of homogeneous and isotropic turbulent flow, to two cases: namely, a simple sheared boundary layer and a large array of regular obstacles. Some very high-resolution measurements of plume dispersion in a water channel, obtained using laser-induced fluorescence (LIF) line-scan techniques are utilised. These data enable us to extract time series of plume centroid position (plume meander) and dispersion in the relative frame of reference in unprecedented detail. Consequently, experimentally extracted PDFs are able to be directly compared with various theoretical forms proposed in the literature. This includes the PDF of plume centroid motion, the PDF of concentration in the relative frame, and a variety of concentration moments in the absolute and relative frames of reference. The analysis confirms the accuracy of some previously proposed functional forms of model components used in fluctuating plume models, as well as suggesting some new forms necessary to deal with the complex boundary conditions in the spatial domain.     

Uncertainty Analysis in Atmospheric Dispersion Modeling

The concentration of a pollutant in the atmosphere is a random variable that cannot be predicted accurately, but can be described using quantities such as ensemble mean, variance, and probability distribution. There is growing recognition that the modeled concentrations of hazardous contaminants in the atmosphere should be described in a probabilistic framework. This paper discusses the various types of uncertainties in atmospheric dispersion models, and reviews sensitivity/uncertainty analysis methods to characterize and/or reduce them. Evaluation and quantification of the range of uncertainties in predictions yield a deeper insight into the capabilities and limitations of atmospheric dispersion models, and increase our confidence in decision-making based on models.     

Heavy metal concentrations (Cd,Cu and Pb) in five aquatic plant species in Tasik Chini,Malaysia

The purpose of this study was to determine the levels of heavy metals namely cadmium (Cd), copper (Cu) and lead (Pb) in the five aquatic plants. For this purpose, the concentration of heavy metals were measured in water and in the five aquatic plant species, Lepironia articulata, Pandanus helicopus, Scirpus grossus, Cabomba furcata and Nelumbo nucifera, in 15 sites from Tasik Chini. The concentrations were different among the plant species as well as among the parts of plants. The highest concentration of heavy metals among the aquatic plants and plant parts was found in the roots of S. grossus. The concentrations of Cd in the leaves and stems of submerged aquatic plant, C. furcata, were higher than concentration of Cd in the leaves and stems of emergent aquatic plant and floating leaf plant. The concentration of Cu in the stem of C. furcata was greater than that in the leaf, while the concentration of Cd was more in the leaf than in the stem. The heavy metal contents of the aquatic plants were in descending order of Pb > Cu > Cd. The metal concentration quotient of leaves/roots and stems/roots (ML/MR and MS/MR) were calculated. The highest internal translocation was found in P. helicopus, while the lowest internal translocation was found in S. grossus.     

景谷民乐火山灰流型铜矿地质及成因

民乐浸染状铜矿产于中三叠统灰流型富钠质熔结凝灰岩中。矿区火山岩主体为细碧角斑岩系，矿床的形成与陆内再生地槽海相火山活动及其4后的热液蚀变作用密切相关。矿体分布明显受火山岩岩性、岩相、层位及构造控制，成因上与火山喷发和爆发作用有关。矿床受后期火山热液、次生富集改造后富化明显。