THE FEATURES OF BIODESTRUCTION PROCESSES OF THE SURFACES OF HYDRAULIC ENGINEERING CONSTRUCTIONS

2017 ◽  
Author(s):  
Marina Vasilenko ◽  
Marina Vasilenko ◽  
Elena Goncharova ◽  
Elena Goncharova ◽  
Yury Rubanov ◽  
...  
Keyword(s):  
Surface Layer ◽  
Environmental Factors ◽  
Food Chain ◽  
Building Materials ◽  
Microbial Growth ◽  
Mineralogical Composition ◽  
Mechanical Action ◽  
Chemical Processes ◽  
Hydraulic Engineering ◽  
Optimal Conditions

The surfaces of building materials of hydrotechnical constructions undergo the process of algae biofouling. The degree of damage depends on the environmental factors that are affect-ed by the level of anthropogenic load areas. Modeling the biofouling process of concrete with algae under laboratory conditions has allowed determining their impact on the building ma-terial, accompanied by changes in chemical and mineralogical composition of the surface of products. The microscopic examination of sample’s surfaces and evaluation of the effective-ness of various ions leaching from building materials shows the results of "algal attack" relat-ed to the acceleration of biodegradation of materials under the influence of aggressive meta-bolic products, mechanical action neoplasms, creating optimal conditions for the development of subsequent aerobic microbial decomposers. To clarify the nature of chemical processes in the system “algocenosis – concrete” the changes of chemical and phase (mineralogical) com-position of the surface layer of concrete sample were studied. The effect that algae produce on hydraulic engineering constructions is due to the fact that these organisms, belonging to phototrophs and standing at the beginning of the food chain, initiate new microbial growth.

THE FEATURES OF BIODESTRUCTION PROCESSES OF THE SURFACES OF HYDRAULIC ENGINEERING CONSTRUCTIONS

2017 ◽  
Author(s):  
Marina Vasilenko ◽  
Marina Vasilenko ◽  
Elena Goncharova ◽  
Elena Goncharova ◽  
Yury Rubanov ◽  
...  
Keyword(s):  
Surface Layer ◽  
Environmental Factors ◽  
Food Chain ◽  
Building Materials ◽  
Microbial Growth ◽  
Mineralogical Composition ◽  
Mechanical Action ◽  
Chemical Processes ◽  
Hydraulic Engineering ◽  
Optimal Conditions

The surfaces of building materials of hydrotechnical constructions undergo the process of algae biofouling. The degree of damage depends on the environmental factors that are affect-ed by the level of anthropogenic load areas. Modeling the biofouling process of concrete with algae under laboratory conditions has allowed determining their impact on the building ma-terial, accompanied by changes in chemical and mineralogical composition of the surface of products. The microscopic examination of sample’s surfaces and evaluation of the effective-ness of various ions leaching from building materials shows the results of "algal attack" relat-ed to the acceleration of biodegradation of materials under the influence of aggressive meta-bolic products, mechanical action neoplasms, creating optimal conditions for the development of subsequent aerobic microbial decomposers. To clarify the nature of chemical processes in the system “algocenosis – concrete” the changes of chemical and phase (mineralogical) com-position of the surface layer of concrete sample were studied. The effect that algae produce on hydraulic engineering constructions is due to the fact that these organisms, belonging to phototrophs and standing at the beginning of the food chain, initiate new microbial growth.

scholarly journals Physicochemical Properties of Handere Clays and Their Use as a Building Material

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Yasin Erdoğan
Keyword(s):  
Physicochemical Properties ◽  
Building Materials ◽  
Raw Materials ◽  
Organic Matter Content ◽  
Volcanic Glass ◽  
Mineralogical Composition ◽  
Matter Content ◽  
Loss On Ignition ◽  
X Ray Diffraction ◽  
Clay Deposits

Handere clay deposits were discovered at Adana in Turkey. These clay units primarily consist of uncoloured claystone, pebbly sandstone, sandstone, siltstone, and mudstone marl and include gypsum lenses and clay levels of various thicknesses in places. The physicochemical properties of these clays have been investigated by different techniques including Scanning Electron and Elemental Analysis (SEM and EDS), mineralogical analyses, chemical and physical analyses, X-ray diffraction (XRD), thermogravimetric differential thermal analysis (TG-DTA), and Atterberg (Consistency) Limits Test. The mineralogical composition deduced from XRD is wide (smectite + palygorskite + illite ± feldspar ± chlorite ± quartz ± calcite ± serpentine) due to the high smectite contents (≈85%). SEM studies reveal that smectite minerals are composed of irregular platy leaves and show honeycomb pattern in the form of wavy leaves in places. The leaves presenting an array with surface edge contact are usually concentrated in the dissolution voids and fractures of volcanic glass. Organic matter content and loss on ignition analysis of raw materials are good for all the studied samples. In summary, Handere clays can be used as building materials in bricks, roof tiles, and cement and as a binder.

Evaluation of the influence of ambient air temperature and air velocity on mortar cement durability using a forced convection solar dryer

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Younes Bahammou ◽  
Mounir Kouhila ◽  
Haytem Moussaoui ◽  
Hamza Lamsyehe ◽  
Zakaria Tagnamas ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Forced Convection ◽  
Air Temperature ◽  
Building Materials ◽  
Ambient Air ◽  
Physical Significance ◽  
Drying Process ◽  
Air Velocity ◽  
Content Type ◽  
Ambient Air Temperature

PurposeThis work aims to study the hydrothermal behavior of mortar cement toward certain environmental factors (ambient air temperature and air velocity) based on its drying kinetics data. The objective is to provide a better understanding and controlling the stability of mortar structures, which integrate the sorption phenomenon, drying process, air pressure and intrinsic characteristics. This leads to predict the comportment of mortar structures in relation with main environmental factors and minimize the risk of cracking mortar structures at an early age.Design/methodology/approachThermokinetic study was carried out in natural and forced convection solar drying at three temperatures 20, 30 and 40°C and three air velocities (1, 3 and 5 m.s-1). The empirical and semiempirical models tested successfully describe the drying kinetics of mortar. These models simulate the drying process of water absorbed by capillarity, which is the most common humidity transfer mechanism in building materials and contain parameters with physical significance, which integrate the effect of several environmental factors and intrinsic characteristics of mortar structures.FindingsThe models simulate the drying process of water absorbed by capillarity, which is the most common humidity transfer mechanism in building materials and contain parameters with physical significance, which integrate the effect of several environmental factors and intrinsic characteristics of mortar structures. The average activation energy obtained expressed the temperature effect on the mortar diffusivity. The drying constant and the diffusion coefficient can be used to predict the influence of these environmental factors on the drying behavior of various building materials and therefore on their durability.Originality/valueEvaluation of the effect of several environmental factors and intrinsic characteristics of mortar structures on their durability.

scholarly journals Use of Ash-and-Slag Wastes after Burning of Fine-Dispersed Coal-Washing Wastes

2018 ◽  
Vol 41 ◽  
pp. 01042
Author(s):  
Vasilii Murko ◽  
Veniamin Khyamyalyainen ◽  
Marina Baranova
Keyword(s):  
Power Plants ◽  
Building Materials ◽  
Negative Impact ◽  
Mineralogical Composition ◽  
Unburned Carbon ◽  
Crushed Rock ◽  
Low Carbon ◽  
Technological Parameters ◽  
Coal Fuel ◽  
Granulated Slag

Effective utilization of ash-and-slag waste generated by coalfired power plants can help significantly to reduce the negative impact on the environment and improve their economic performance. Studies have been made of the mineralogical composition of ash-and-slag wastes obtained after the combustion of water-coal fuel based on fine-dispersed coal-washing waste (filter cake) in a specially designed boiler with a vortex combustion system. The possibility of effective use of ash-and-slag wastes for the production of building materials, primarily mortar mixes, widely used for mining works on mine openings, laying the worked out space, etc. (high content of silicon oxide and aluminum oxide is combined with a low carbon content in other words a negligible unburned carbon loss). The optimum percentage ratio of the initial components of the filling mixture based on ash-and-slag wastes and crushed rock (granulated slag) has been established. The results of experimental tests of hardening tabs on the strength under uniaxial compression are presented. It has been established that a sample containing 18% of ash-and-slag wastes, 33% of a granulated slag and 19% of cement, corresponds to the required technological parameters for the strength and cement content.

Memory impairments and its interaction with environmental factors in children aged 6 to 8 years living in gharb plain (N-w of Morocco)

2011 ◽  
Vol 26 (S2) ◽  
pp. 264-264 ◽  
Author(s):  
F.-Z. Azzaoui ◽  
H. Hami ◽  
A.O.T. Ahami
Keyword(s):  
Working Memory ◽  
Environmental Factors ◽  
Building Materials ◽  
Short Term Memory ◽  
Rural Children ◽  
Short Term ◽  
Term Memory ◽  
North West ◽  
Memory Impairments ◽  
The North

IntroductionThe “Gharb” plain (area of our study) localized in the North-West of Morocco is one of the most important agricultural and industrial regions of the Kingdom. Unfortunately, it suffered from the increase of different polluting human activities which expose the population, especially children, to serious neurobehavioral problems.Objective and aimsEvaluation of the short term memory and working memory in urban, periurban and rural schooled children (aged 6 to 8 years) living in Gharb plain and studying the relationship between the performance in this test and the quality of environment.MethodsMemory Sub-test of WISC III (Wechsler Intelligence Scale for Children) and questionnaire about some environmental conditions.ResultsThe obtained results had shown that 3,64% periurban children and 3,03% rural children suffer from short memory impairments and no impairments in urban children were registered. For working memory, 21,05%, 47,06% and 66,67% of impairments were found in urban, periurban and rural children respectively.Moreover, a significant correlations between the performances of short term memory and building materials (p < 0.05), source of pollution near the school (p < 0.05), and consumption of well water (p < 0.001) were registered.ConclusionsThe memory impairments recorded in these children appeared in connection with environmental factors, but a deeper investigation is needed for studying all these factors, in addition to others (psychological, socio-economical, and nutritional) ones.

scholarly journals Summer and winter living coccolithophores in the Yellow Sea and the East China Sea

2014 ◽  
Vol 11 (3) ◽  
pp. 779-806 ◽  
Author(s):  
J. Sun ◽  
X. Y. Gu ◽  
Y. Y. Feng ◽  
S. F. Jin ◽  
W. S. Jiang ◽  
...  
Keyword(s):  
Surface Layer ◽  
Environmental Factors ◽  
East China Sea ◽  
Correspondence Analysis ◽  
Yellow Sea ◽  
The Yellow Sea ◽  
East China ◽  
The East China Sea ◽  
China Sea ◽  
Living Coccolithophores

Abstract. This paper describes the distribution of living coccolithophores (LCs) in the Yellow Sea and the East China Sea in summer and winter, and its relationship with environmental factors by canonical correspondence analysis (CCA). We carried out a series of investigations on LCs distribution in the Yellow Sea and the East China Sea in July and December 2011. 210 samples from different depths were collected from 44 stations in summer and 217 samples were collected from 45 stations in winter. Totally 20 taxa belonging to coccolithophyceae were identified using a polarized microscope at the 1000 × magnification. The dominant species of the two seasons were Gephyrocapsa oceanica, Emiliania huxleyi, Helicosphaera carteri, and Algirosphaera robusta. In summer the abundance of coccolithophore cells and coccoliths ranged 0–176.40 cells mL−1, and 0–2144.98 coccoliths mL−1, with the average values of 8.45 cells mL−1, and 265.42 coccoliths mL−1, respectively. And in winter the abundance of cells and coccoliths ranged 0–71.66 cells mL−1, and 0–4698.99 coccoliths mL−1, with the average values of 13.91 cells mL−1 and 872.56 coccoliths mL−1, respectively. In summer, the LCs in surface layer were mainly observed on the coastal belt and southern part of the survey area. In winter, the LCs in surface layer had high value in the continental shelf area of section P. The comparison among section A, section F, section P and section E indicated lower species diversity and less abundance in the Yellow Sea than those in the East China Sea in both seasons. Temperature and the nitrate concentration may be the major environmental factors controlling the distribution and species composition of LCs in the studying area based on CCA. Abbreviations: LCs: Living Coccolithophores; CCA: canonical correspondence analysis; DCM: Deep Chlorophyll Maximum

Sulphur Dioxide Emissions during the Firing of Ceramic Bodies Based on Class C Fly Ash

2019 ◽  
Vol 296 ◽  
pp. 149-154
Author(s):  
Radomír Sokolář ◽  
Martin Nguyen
Keyword(s):  
Fly Ash ◽  
Sulphur Dioxide ◽  
Power Plants ◽  
Building Materials ◽  
Porous Ceramic ◽  
Mineralogical Composition ◽  
High Volume ◽  
Ceramic Tiles ◽  
Sulphur Dioxide Emissions ◽  
Class C

Fluid fuel combustion technology in coal-fired power plants is very popular in the Czech Republic, resulting in a relatively high production of a specific by-product - fluidized fly ash (class C according to ASTM definition), which differs from the classical high-temperature fly ash in mineralogical composition with a high sulphur content of anhydrite CaSO4. Fluidized ash is not yet used in the production of fired building materials, where it could be used as a source of calcium oxide (for example, the production of porous ceramic tiles). However, high volume of sulphur dioxide emissions during the re-firing of fluidized fly ash in ceramic raw materials mixtures has been solved. The aim of the paper is definition of temperature ranges of anhydrite decomposition (formation of SO2 emission) from pure class C (fluidized) fly ashes from different sources (power plants) depending on granulometry of fly ash especially.

scholarly journals Guidance on Design and Construction of the Built Environment Against Wildland Urban Interface Fire Hazard: A Review

2019 ◽  
Vol 56 (5) ◽  
pp. 1853-1883 ◽  
Author(s):  
Paolo Intini ◽  
Enrico Ronchi ◽  
Steven Gwynne ◽  
Noureddine Bénichou
Keyword(s):  
Environmental Factors ◽  
Built Environment ◽  
Fire Protection ◽  
Building Materials ◽  
Fire Hazard ◽  
Future Research ◽  
Wildland Urban Interface ◽  
Protection Measures ◽  
Risk Areas ◽  
Design And Construction

Abstract Wildland-Urban Interface (WUI) fires, a worldwide problem, are gaining more importance over time due to climate change and increased urbanization in WUI areas. Some jurisdictions have provided standards, codes and guidelines, which may greatly help planning, prevention and protection against wildfires. This work presents a wide systematic review of standards, codes and guidelines for the design and construction of the built environment against WUI fire hazard from North American, European, Oceanic countries, alongside with trans-national codes. The main information reviewed includes: the definition of WUI hazards, risk areas and related severity classes, the influence of land and environmental factors, the requirements for building materials, constructions, utilities, fire protection measures and road access. Some common threads among the documents reviewed have been highlighted. They include similar attempts at: (a) defining WUI risk areas and severity classes, (b) considering land factors including the defensible space (also known as ignition zones), (c) prescribing requirements for buildings and access. The main gaps highlighted in the existing standards/guidelines include lacks of detailed and widespread requirements for resources, fire protection measures, and lacks of taking into account environmental factors in detail. The main design and construction principles contained in the reviewed documents are largely based on previous research and/or good practices. Hence, the main contributions of this paper consist in: (a) systematically disseminate these guidance concepts, (b) setting a potential basis for the development of standards/guidelines in other jurisdictions lacking dedicated WUI fire design guidance, (c) highlighting gaps in existing standards/guidelines to be addressed by current and future research.

scholarly journals Environmental Factors Causing the Development of Microorganisms on the Surfaces of National Cultural Monuments Made of Mineral Building Materials—Review

Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1203
Author(s):  
Elżbieta Stanaszek-Tomal
Keyword(s):  
Environmental Factors ◽  
Building Materials ◽  
Ion Concentration ◽  
Physical Factors ◽  
Comprehensive Overview ◽  
Hydrogen Ion Concentration ◽  
Factors Affecting ◽  
Stone Concrete ◽  
The Impact ◽  
Cultural Monuments

The ability of microorganisms to degrade building materials depends on several factors. Biological corrosion occurs in close dependence with chemical and physical factors affecting microorganisms. The growth and development of microorganisms is stimulated by external stimuli, i.e., environmental factors. Microorganisms have a relatively large tolerance range for changes in environmental conditions. Under the right conditions, microorganisms thrive very well. The adverse effects may cause the inhibition of cell growth, damage, or lead to the death of the microorganism. Considering the impact of environmental factors on microorganisms, it is not possible to identify the most important of them. The result effect of overlapping factors determines the possibility of the growth of certain microorganisms. The main factors affecting the growth are temperature, humidity, hydrogen ion concentration in the environment, oxidoreductive potential, water activity in the environment, and hydrostatic pressure. This article provides a comprehensive overview of the factors causing biodeterioration. The influence of external/internal environment on the surface of cultural monuments made of mineral building materials, i.e., stone, concrete, mortar, etc., is presented.

scholarly journals Evaluation of New Applications of Oil Shale Ashes in Building Materials

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 765
Author(s):  
Mustafa Cem Usta ◽  
Can Rüstü Yörük ◽  
Tiina Hain ◽  
Peeter Paaver ◽  
Ruben Snellings ◽  
...  
Keyword(s):  
Oil Shale ◽  
Building Materials ◽  
Mineralogical Composition ◽  
Accelerated Carbonation ◽  
Zero Waste ◽  
Clay Bricks ◽  
Carbon Neutral ◽  
New Applications ◽  
Future Utilization

Achieving sustainable zero-waste and carbon neutral solutions that contribute to a circular economy is critically important for the long-term prosperity and continuity of traditional carbon-based energy industries. The Estonian oil shale (OS) sector is an example where such solutions are more than welcome. The combustion of OS generates a continuous flow of ashes destined to landfills. In this study, the technical feasibility of producing monolith building materials incorporating different OS ashes from Estonia was evaluated. Three binder systems were studied: self-cementation of the ashes, ceramic sintering in clay brick production and accelerated carbonation of OS ash (OSA) compacts. Results showed that most of the OSAs studied have low self-cementitious properties and these properties were affected by ash fineness and mineralogical composition. In case of clay bricks, OSA addition resulted in a higher porosity and improved insulation properties. The carbonated OSA compacts showed promising compressive strength. Accelerated carbonation of compacted samples was found to be the most promising way for the future utilization of OSAs as sustainable zero-waste and carbon neutral solution.

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