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Multidimensional Classification Method in the Study of Natural and Anthropogenic Systems
Get PDF In this article the problem of build and use classification of multivariate observations; this issue has played a leading role in the knowledge of the world around us. When studying natural- anthropogenic systems have the greatest value probably-statistical simulation methods of objects, phenomena and processes. Among classification technologies to focus on situations of constructing classifications if there is no a priori information about the taxonomic structure of the observations. In the work described the rationale for the original statistical criterion Z2 and G-classification methods of multivariate observations. This used quantity conversion method dependent traits in an equivalent number of independent. G-method lets you select homogeneous classes and sub-classes of observations, evaluate differences between taxons, determine the informative signs and much more. The application of the classification shown in the case study method regularities of formation of chemical composition of mine waters in the Eastern Donbass. It is four main types of changes in the composition of mine waters: the first type has the most significant impact on environmental degradation in the region; the second and third types reflects the influence composition of groundwater chloride in the composition of mine water; the fourth type is the soda water, which may indicate the presence of the region's oil and gas fields
A Study about Energy Demand and Consumption in the Cement Industrial Sector in the Brazilian State of Minas Gerais
Get PDF The Portland cement is one of the most important building materials and highly employed by mankind. Its high participation in human development, as a basic material for any type of construction, characterizes the cement industry as one of the main sectors for the economic and social development. It represents approximately 3% of energy consumption in Minas Gerais (MG), a Brazilian State. To perform this study, it was collected a set of energy consumption parameters and process data, besides economic indicators. Minas Gerais houses the majority of cement plants installed in Brazil. Each stage of production was identified and quantified as related to the energy consumption. Initially, the projection of the final consumption of the main energy sources was developed with the average growth method. Then, the future energy demand was calculated using the ENPEP-BALANCE model, for a 20-year analysis period. Results showed that the final energy demand of this sector in the State of Minas Gerais could vary from 1,475 to 2,642 thousand toe, which represents about 34% more or less 15% of the registered demand of the base year. Last, CO2 emissions were projected for the considered scenarios
Impact of Operational Condition on the Membrane Permeate Flux and Quality of Domestic Wastewater Treatment using Hollow Fiber Membrane Module in Cross-Flow Mode
Get PDFIn this paper, the impacts of process conditions on the membrane permeate flux (J) and the quality of effluent in domestic wastewater treated by using 0.1 μm hollow fiber membrane module in cross-flow mode were quantificationally analyzed with a statistical method. The results showed that (1) trans-membrane pressure (TMP), crossflow velocity (u), mixed liquor suspended solids (MLSS), dissolved oxygen concentration (DO), pH, temperature (T), sludge retention time (SRT) and hydraulic retention time (HRT) were all the influencing factors of the permeate flux. Among them, MLSS, T, SRT and HRT are negative contributors to the permeate flux while TMP, u, DO and pH are positive contributors. In addition, the quantitative relationship between the permeate flux and process conditions is established. (2) TMP and u had no effect on the quality of effluent COD while other operating conditions were the influencing factors. Only HRT had a negative effect on the quality of effluent NH3-N. The quantitative relationships between COD, TOC, NH3-N and process conditions were also established. These mathematical expressions, to some extent, could be used to optimize operational conditions, predict the permeate flux and efficiency of domestic wastewater treatment using hollow fiber membrane module in cross flow mode
Protein Adsorption Behavior on the Surface of the Microfiltration Membrane Based on a Quartz Crystal Microbalance (QCM)
Get PDFHow to fast and efficiently determinate the fouling behavior of the microfiltration membrane has great significance for the industrial membrane application. In this paper, the MF membrane was put on the surface of a gold-coated quartz crystal of QCM to study the adsorption behavior of protein at different conditions. The adsorbed mass increased with the increasing of concentration, ionic strength and temperature while decreased with the increasing of pH. Then the BSA adsorption results were compared with the corresponding membrane flux in dead-end cell at the identical conditions. Furthermore, the BSA adsorption process can be described by Langmuir and Freundlich isotherms very well. These results suggested that directly putting the membrane on the surface of a gold-coated quartz crystal of QCM can be used as a rapid and efficient approach to study protein fouling on the membrane surface. This approach using QCM and a small piece of the membrane could yield quantitative information for adsorption kinetics investigation and reduce the workload in large-scale industrial project
Arbuscular Mycorrhiza Fungi Strengthen the Beneficial Effects of Warming on the Growth of Gynaephora Menyuanensis Larvae
Get PDF Herbivores experience an unprecedented variously impacts of climate warming. Besides, arbuscular mycorrhiza fungi (AMF) also is influence on herbivores through their common host plants. Surprisingly, there are no reports about how AMF affect the responses of herbivores to warming. To close this gap, we conducted a two factors experiment to research the effects of warming, fungicide (AMF suppression), and their interaction on the development of Gynaephora menyuanensis larvae, an endemic generalist herbivore species in northeastern Tibetan Plateau, and nitrogen content of Elymus nutans, which was the main food of G. menyuanensis. Warming significantly advanced the pupation time (PT), expanded the phenomena of protandry and increased the growth rate (GR) of G. menyuanensis larvae. Fungicide not affected the development of G. menyuanensis larvae, despite their negative effects on the content of E. nutans. Warming with fungicide decreased the GR of G. menyuanensis compared with warming treatment. In other words, AMF strengthen the beneficial effects of warming to G. menyuanensis. This study provides the first evidence of the impacts of AMF on the response of herbivore to warming
The Development and Application of the Acrylamide Kind Polymers for Tertiary Oil Recovery in China
Get PDF As many oilfields shift from high permeability and medium-high permeability to low permeability and ultra-low permeability, the complexity and specificity of their formation channels increase, and the requirements on injectivity and liquidity of polymer flooding become increasingly stricter. This paper, from the perspective of the molecular configuration of poly(acrylamide) (PAM), gives an introduction to their respective characteristics, and analyzes the applicability of PAMs in tertiary oil recovery on the basis of the applications of polymer flooding in China. The study suggests that, on the one hand, the problem that urgently needs to be solved at present is achieving the viscosification of polymers with medium-low molecular weight or low molecular weight in high-temperature and high-salt conditions; on the other hand, researchers shall change their original research thoughts, shift from large-scale design of original PAM products to one-to-one “customized” research on and development for meeting specific oilfield demands from the perspective of polymer molecular structure
Development of a Transient Model for Evaluation of Shell and Tube Heat Exchanger with Helical Baffles Applied for SiO2 Nanofluid
Get PDF While integrated sizing and analysis procedures for helical shell-and-tube heat exchangers are available in the technical literature, the same does not hold for differential transient methods. This work aims to develop a differential transient model for a shell-and-tube heat exchanger with helical baffles with one pass in the shell and two passes in the tubes, considering one-dimensional variation along the length of the equipment. It is intended to determine the fluids temperature profiles and overall heat transfer coefficient along the equipment. Temperature correction factor Ft, heat load and pressure losses were estimated with the model. The thermophysical properties of the fluids were locally evaluated by using published predictive correlations. Simulations were performed using Python framework computing environment assuming a SiO2 nanofluid
Study on the Water-Saving Irrigation Technology in the Slope Vegetation Restoration of the Mining Area Dump
Get PDF With the development and utilization of coal resources, the surface vegetation is destroyed and soil erosion is more and more serious. Open-pit coal mine on typical steppe causes very strong artificial erosion landform remodeling, especially mining dump slope, needing to take reasonable measures for its vegetation restoration. Irrigation is one of main means to ensure the vegetation growth on anthropogenic landforms, which can make up for a lack of atmospheric precipitation and coordinated uneven distribution of water space and enhance its competitiveness. The research focuses on different irrigation methods in the vegetation restoration of coal mine dump slope, which is slight spraying, drip irrigation and micro irrigation, where water shortages, lack of regular power and slope topography. Suitable irrigation methods are determined better to vegetation restoration and reconstruction through studying the characteristics of three irrigation methods, soil moisture content, vegetation coverage and biomass on the ground. Appropriate way of irrigation not only make more rational use of limited water resources, but also promote plant growth and protect coal mine slope, effectively reduce soil erosion
A New Biomarker in Diagnostic in Spirometry Exams with the Application of Wavelets
Get PDF This article presents a new medical biomarker that can be use in spirometry tests. These biomarker was obtained through a set of tests, where Meyer wavelet was applied and allows through one statistical analysis of the data obtained in pulmonary exams, could be possible to obtain numerical indicators that assist the physician achieve diagnosis in patients pulmonary function as normal, obstructive or restrictive
Comparison Among Monte Carlo Based Burnup Codes Applied to the GFR Demonstrator ALLEGRO
Get PDF This paper aims to compare three Monte Carlo (MC) burnup based codes, i.e. MCNP6, Monteburns and Serpent on a future prototype reactor, named ALLEGRO, based on Gas cooled Fast Reactor (GFR) technology. GFR reactors are one of the proposed Generation-IV fast reactors; ALLEGRO facility is scheduled to be built in Europe as a GFR demonstrator, so its deepened simulation can help in its future development. The present study follows other researches already performed and aims to exhibit the different approaches in burnup calculations applied to a gas cooled fast reactors, i.e. this paper would like to show and to compare some results concerning nuclear parameters as keff and flux spectra, as well as the mass inventories versus burnup for some nuclides evaluated with different Monte Carlo codes. From obtained results, it seems to exist some differences in evaluation of nuclear parameters, mainly in effective multiplication factor and in mass inventories. The remaining differences are mainly related to calculation time: indeed between the fastest, that is SERPENT, and the slowest, that are MCNP6 and MONTEBURNS, the differences are about one order of magnitude. As far as precision is concerned, it was considered the standard only for effective multiplication factor and it seems that all codes are in good agreement