filtration capacity
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Author(s):  
O. P. Abramova ◽  
◽  
D. S. Filippova ◽  

Taking into account the world and domestic experience of studying the ontogenesis of lithospheric hydrogen a combination of coupled hydrochemical, geochemical and microbiological factors of the accumulation of this natural gas together with methane in the terrigenous formations of the sedimentary cover is justified. It is predicted that various hydrochemical and microbiological processes that cause the development of carbon dioxide and sulfate corrosion of engineering structures, as well as cement of reservoir rocks and tires, can occur together with methane at industrial facilities of underground storage of hydrogen. The risks of reducing the volume of injected hydrogen in underground storage in addition to diffusion losses can be associated with geobiological factors, including the conversion of hydrogen into CH4 and H2S due to microbial activity, chemical interaction of hydrogen with minerals of reservoirs and tires, accompanied by changes in filtration-capacity and geomechanical properties, hydrogen embrittlement of metal structures of ground and underground well equipment. Keywords: geobiology; hydrogen; methane; underground storage; methanogenesis; acetogenesis; sulfate reduction.


Author(s):  
Jayamathi Govindaraj ◽  
U. Vidhya Rekha ◽  
Keerthidaa Govindaraj ◽  
S. Bhuminathan

Urine albumin-to-creatinine ratio have predictive values for hypertension, diabetes mellitus, renal dysfunction etc. Albumin-to-creatinine ratio represents the severity of proteinuria,  indicates high probability of damage to glomerular filtration capacity of the kidney and is of great diagnostic relevance. Emerging data suggested that reduction of albuminuria leads to reduced risk of adverse renal and cardiovascular events but also steps should be taken to suppress albuminuria to prevent future renal and cardiovascular adverse events. This review discusses the association between albuminuria and adverse cardiovascular and renal outcomes in type 2 diabetes and hypertension. This study aimed to review the association between normal ranges of urine albumin-to-creatinine ratio to cardiovascular and all-cause mortality.


2021 ◽  
Vol 938 (1) ◽  
pp. 012021
Author(s):  
AV Gudimov

Abstract High tolerance to pollution and filtration capacity of some seston-eating bivalves and mussels of g. Mytilus first of all, principally determine mussel populations as a powerful natural biofilter. Both marine and freshwater mussels consume relatively large amounts of seston, feeding directly on the primary producers. Particles with contaminants extracted from ambient water during the filtration are accumulated in mussel pseudofaeces and faeces discharged after digestion. These specific particles of faeces and soft pseudofeaces become very suitable substrata for bacteria development with following contaminant destruction. Moreover, such biodeposits appeared to be the nutritious food for bottom detritophages, in particular of polychaetes and amphipods. Some fluid metabolites excreted by mussels, i.e. dissolved organic matter (DOM) have a pronounced biological activity to producers. In general, mussels possess high resistance to acute and chronic pollution stress, although their growth may slow down and even stops. In clean conditions food supply is the most important factor in determining activity and growth rate of mussels for northern environment. Mussel and some other aquaculture, as a relatively new application of environmental engineering is able to improve the recycling of nutrients from wastewater to bioproduction and greatly reduce the risk of environmental degradation in the coastal zone.


Processes ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 2021
Author(s):  
Alexey V. Vakhin ◽  
Mohammed A. Khelkhal ◽  
Arash Tajik ◽  
Nikita E. Ignashev ◽  
Tatiana O. Krapivnitskaya ◽  
...  

The present paper reports experiments on microwave heating of a carbonate oil-containing rock sample in the presence and absence of an iron-magnetite-based nanocatalyst. It has been shown that the used catalyst improves the processes of destructive hydrogenation of resins and asphaltenes compounds in the oil. The chemical reactions analysis demonstrated a decrease in asphaltenes content and in their molecular weight, which increases the filtration capacity of the oil fluid in the reservoir rock porous medium. Moreover, the content of non-extractable organic matter in the rock sample after experiments and after oil extraction was determined. It has been found that the absence of the catalyst causes the least increase in the content of non-extractable organic matter in the rock. This fact is related to the intensive processes of resinous-asphaltene compounds destruction especially at the level of peripheral groups which are the most condensed fraction, and hence leads to a decrease in their solubility in the organic medium and eases their adsorption on the mineral skeleton surface.


2021 ◽  
Vol 2021 ◽  
pp. 50-57
Author(s):  
C. Silva ◽  
T. Sousa ◽  
J. Bessa ◽  
F. Cunha ◽  
M. Costa ◽  
...  

Despite the growing appearance of new solutions for social masks, there are still few aimed for the use by professionals in frequent contact with the public, since depending on the of the functions they perform, still have special needs regarding thermophysiological comfort, high protection level and reusability, such as firefighters and police officers. Aiming at the development of a multilayer filtration system combining threedimensional and planar fibrous structures, the present study intends to verify the feasibility of applying warpknit spacers as diffuser filters for nano and micro particles. Therefore, three different spacer structures performance was studied, and then combined with planar knit structures to enhance the comfort characteristics and its bacterial filtration efficiency (BFE). The diffusion filtration performance of the samples, due to the particle size, it was found a direct relation between the outer layer density and porosity with its filtration capacity of microparticles. Moreover, the increase in the spacer thickness revealed more problems diffusing water vapor molecules. To achieve the standard requirements, the samples Techno_1 and 2 were developed and tested. The addition of a new fibrous structure increased substantially the filtration efficiency without damaging the comfort characteristics of the Spacers. Considering the BFE standard tests for facemask certification, despite it was possible to achieve filtration rates above 70% for the samples Techno_1 and 2. In addition, its washability and performance durability were tested and stated as viable to be applied as a social facemask with level III of protection for at least 25 washing cycles, despite having noticed a decrease in the filtration efficiency, in both samples, in the order of 10%, due to the unbalance of mechanical properties of the fibrous structures in the multilayer systems.


2021 ◽  
Author(s):  
Azar Asadi ◽  
Foad Gholami ◽  
Ali Akbar Zinatizadeh ◽  
Hasan Jaberi

Abstract In this research, the application of mesoporous carbon CMK-3 and modified CMK-3 (M-CMK-3) to improve antifouling and rejection rate of polyethersulfone NF membrane was assessed. CMK-3 was modified with H-acid to increase hydrophilic characteristics of CMK-3. The synthesized CMK-3 and modified CMK-3 membranes exhibited a high pure water flux and also flux recovery ratio (up to 95%) compared with bare NF membrane. Also, the membranes with optimum additive loading (0.1wt%) of CMK-3 and M-CMK-3 were compared to reject different salts and dyes. From the obtained results, the membrane embedded with M-CMK-3 showed higher rejection rate rather than bare NF membrane (up to 95 % for Na2SO4and 64% for CaCl2) and also the flux permeability was increased from 6.44 for bare NF membrane to 20.11 kg/m2.h for the membrane embedded with M-CMK-3. A higher rejection data for different dyes under different pH conditions (up to 90%) was reported for the synthesized membrane embedded with M-CMK-3. After all, from the obtained data, M-CMK-3 with higher negative surface charge presented a higher performance to remove salts and dyes. This research was aimed to develop cost-effective NF membranes with high antifouling properties and super high filtration capacity for removing dyes and salts from wastewaters.


2021 ◽  
Vol 3 (163) ◽  
pp. 68-74
Author(s):  
O. Kravchuk

A system of two differential equations which describes the movement of fluid in a pipe with a variable flow rate and the conditions for the fluid outflow through the walls of drainage pipelines into the surrounding soil is considered. It is reasoned that the second term in the original equation, which takes into account energy losses associated with a flow rate variation along the length, can be neglected without a substantial error. The considered system is reduced to dimensionless form by introducing original variables. The coefficient of collecting drainage pipeline resistance «ζl» and the generalized parameter «A», which take into account the structural and hydraulic characteristics of the considered flow, are two main parameters used in the analysis. The concept of an infinitely long drainage pipeline (a pipeline with an infinite walls filtration capacity) is introduced in the article. Also it is noted that such pipeline will have a maximum throughput comparing to pipes of the same diameter but limited length. Quite simple and practical calculated dependencies for the determination of the nature of flow rate variation and pressure drop along the length of the pipeline were received on the basis of the conducted analysis. Important characteristics of pressure distribution pipelines were calculated on the basis of offered formulas. Corresponding graphical dependencies were built for visibility. In particular, graphs of the flow rate variation at the end of the distributor, depending on the design and filtration characteristics of the «soil-drain» system, are presented. Graph that shows the dependence of the variation in the flow rate distribution unevenness along the length of the drainage pipe at various ​​hydraulic conductivity values of the surrounding soil is important for understanding the drainage pipelines particularity. The necessity to take into account the nature of the flow rate connection unevenness along the length for obtaining reliable results for real drainage pipelines calculation is demonstrated.


Author(s):  
Zh. Sh. Zhantayev ◽  
G. Zh. Zholtayev ◽  
B. Iskakov ◽  
А. Gaipova

The presence of areas of accumulation of hydrocarbons in the sedimentary strata is genetically related both to the conditions of sedimentation and to secondary changes in the properties of the geological environment, caused along with other and geodynamic processes. At the same time, it is the stress-strain state that is the key characteristic of the environment, the analysis of which makes it possible to predict the influence of geodynamic factors that cause deformation processes in the sedimentary stratum, on the formation of zones of decompaction and increased fracturing, areas of increased filtration-capacity properties of reservoir rocks, the direction of natural migration of hydrocarbons. Using the example of 3D seismic data obtained at the Akshabulak area, the possibility of integrating geomechanical modeling and additional express analysis of seismic data in solving problems related to determining the probable places of accumulations and directions of natural migration of hydrocarbons is shown.


Author(s):  
O.A. Kravchuk ◽  

A system of two differential equations, which describes the fluid motion in a pipe with a variable flow rate and the conditions for fluid entry through the drainage pipelines walls from the surrounding soil, is considered. It is shown that for the studied case the second term in the original equation can be neglected without a significant error. The system is reduced to a dimensionless form by introducing the original variables. The solution of this equations system is given in a dimensionless form. Two main parameters are used in the analysis: the coefficient of collecting drainage pipeline resistance "ζl" and the generalized parameter "A", which takes into account the structural and hydraulic characteristics of the considered flow. Also, the concept of an infinitely long drainage pipeline or, which is the same, a pipeline with an infinite walls filtration capacity of the drainage pipeline is introduced in the article. It is noted that such pipeline will have a maximum throughput compared to pipes of the same diameter but limited length. Sufficiently simple and convenient calculated dependencies for the determination of the nature of flow rate variation and pressure drop along the length of the pipeline were obtained on the basis of the conducted analysis. Series of calculations of important characteristics for such pipes were carried out on the basis of offered formulas. Corresponding graphical dependencies were built for visibility. In particular, graphs of the flow rate variations at the end of the collector, depending on the design and filtration characteristics of the “soil-drain” system, are presented. Graph, that shows the dependence of the change in the flow rate connection unevenness along the length of the drainage pipeline at various hydraulic conductivity values of the surrounding soil, is important for understanding the drainage pipes particularity. The necessity to take into account the nature of the flow rate connection unevenness along the length for obtaining reliable results when calculating real drainage pipelines is shown in the article.


Georesursy ◽  
2021 ◽  
Vol 23 (2) ◽  
pp. 170-178
Author(s):  
Tatyana G. Isakova ◽  
Tatyana F. Diakonova ◽  
Alena D. Nosikova ◽  
Georgy A. Kalmykov ◽  
Alexander V. Akinshin ◽  
...  

The aim of the work is to predict the filtration capacity of reservoirs based on core and well logs data at the stage of petrophysical study of rocks before the start of active development of the object. All the results were obtained from the data of porometric characteristics of rocks on the example of the vikulovskaya series’s deposits of the Krasnoleninsky arch. The patterns of changes in pore sizes and their contribution to the total filtration depending on the lithophysical type of the rock were established on the core plug. A classification of rocks by pore radii is proposed, and a method for assessing the filtration capacity of reservoirs based on well logs data is developed, with the calculation of the share of each layer in the planned perforation interval


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