Microbiological corrosion of building materials

The research results in the field of microbiological corrosion of building materials of domestic and foreign experts are presented. It is shown that microorganisms cause corrosion of concrete on cement and other binding metal and other materials. Metals in the order of decreasing the rate of biocorrosion are arranged in the following row: aluminum, mild steel, zinc, brass, copper, stainless steel. Concrete, due to its high surface activity, is capable of adsorbing a wide variety of substances, including microorganisms: bacteria and mycelial fungi. Among bacteria, nitrifying agents, thionic, iron and silicate bacteria and others participate in the corrosion of cement concrete (mainly due to their acid secretions). According to the data of a number of authors, on the surface of stone building materials mycelial fungi of the genera Penicillium, Aspergillus, Trichoderma, Cephalosporium prevail. Biodeterioration in this case mainly comes down to the disruption of cohesion of constituent components as a result of exposure to mineral or organic acids, as well as enzymes and due to chemical reactions between the cement stone of solutions and concretes and the waste products of microorganisms. The compositions of bituminous composites at various ratios of the materials used without inclusion in the composition of fungicides showed non-fungal resistance and non-fungicide. Comparison of concrete on gypsum and phosphogypsum binders showed that samples on a phosphogypsum binder overgrow microorganisms somewhat more, wood materials are subject to significant biodeterioration at high humidity. Biodegradation of wood occurs mainly due to the use of mushrooms as food sources of cellulose, lignin and other components. Synthetic polymers and materials based on them are significantly superior to natural polymers in biostability. However, under certain operating conditions, they are damaged by biological agents. Biological damage to plastics, as well as other materials, occurs simultaneously with their aging under the influence of external physical and chemical factors (ultraviolet radiation, water, temperature changes, etc.). Additives that are usually always present in polymer compositions (fillers, plasticizers, stabilizers, antioxidants, modifiers, pigments, etc.) significantly affect the biostability of polymeric materials. One of the effective ways to increase the biostability of composite building materials is the introduction of fungicidal additives in their composition. It is also shown that of great importance in increasing the durability and increasing the life of some building structures (metal products, communications, underground pipelines and some others) is their protection by paint and varnish coatings.

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Polymeric Materials Used for Immobilisation of Bacteria for the Bioremediation of Contaminants in Water

Polymers ◽

10.3390/polym13071073 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1073

Author(s):

Dmitriy Berillo ◽

Areej Al-Jwaid ◽

Jonathan Caplin

Keyword(s):

Agricultural Waste ◽

Polymeric Materials ◽

Polluted Soil ◽

Natural Polymers ◽

Planktonic Cells ◽

Waste Products ◽

Applied Microbiology ◽

Immobilised Cells ◽

Materials Used ◽

Synthetic And Natural Polymers

Bioremediation is a key process for reclaiming polluted soil and water by the use of biological agents. A commonly used approach aims to neutralise or remove harmful pollutants from contaminated areas using live microorganisms. Generally, immobilised microorganisms rather than planktonic cells have been used in bioremediation methods. Activated carbon, inorganic minerals (clays, metal oxides, zeolites), and agricultural waste products are acceptable substrates for the immobilisation of bacteria, although there are limitations with biomass loading and the issue with leaching of bacteria during the process. Various synthetic and natural polymers with different functional groups have been used successfully for the efficient immobilisation of microorganisms and cells. Promise has been shown using macroporous materials including cryogels with entrapped bacteria or cells in applications for water treatment and biotechnology. A cryogel is a macroporous polymeric gel formed at sub-zero temperatures through a process known as cryogelation. Macroporous hydrogels have been used to make scaffolds or supports for immobilising bacterial, viral, and other cells. The production of composite materials with immobilised cells possessing suitable mechanical and chemical stability, porosity, elasticity, and biocompatibility suggests that these materials are potential candidates for a range of applications within applied microbiology, biotechnology, and research. This review evaluates applications of macroporous cryogels as tools for the bioremediation of contaminants in wastewater.

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Resistance of Binding Systems of Various Compositions to the Action of Molds

Stroitel nye Materialy ◽

10.31659/0585-430x-2020-786-11-41-46 ◽

2020 ◽

Vol 786 (11) ◽

pp. 41-46

Author(s):

V.V. STROKOVA ◽

◽

V.V. NELUBOVA ◽

M.N. SIVALNEVA ◽

M.D. RYKUNOVA ◽

...

Keyword(s):

Aging Process ◽

Building Materials ◽

Environmental Safety ◽

Fungal Resistance ◽

Building Structures ◽

Vital Activity ◽

Regulatory Documents ◽

Living Organisms ◽

Biological Corrosion ◽

Test Objects

The dynamic development of urbanization contributes to an increase in emissions of industrial waste, which is the cause dysfunction of the ecosystem balance and leads to the development of biological corrosion on building materials associated with the products of the vital activity of microorganisms. In this regard, it is necessary to assess the resistance of composites to predict the durability of building structures under conditions of biological influence of microorganisms. Binder systems of various compositions were studied: cementless nanostructured binders (NB) based on quartz sand and granodiorite, gypsum, Portland cement and alumina cement. The toxicity of binders was assessed by biotesting on living organisms – cladocerans Daphnia Magna – according to the criteria of the intensity of their growth and viability. As a result, the high environmental safety of NB is substantiated, and the ranking of the studied binders according to the degree of increase in their toxicity to test objects is presented. Fungal resistance was assessed by the ability of molds for growing and reproduction on the studied samples. It was found that the most active in terms of the development of binders were representatives of the genus Aspergillus, the intensity of growing of which in all variants did not decrease below 3 points. Gypsum and NB were especially vulnerable, where the degree of fouling repeatedly reached 5 points. Even the initially biostable cement, after the aging process, lost its stability at different extent. The obtained results indicate the need to increase the resistance of composites for various purposes under conditions of biocorrosion at the stage of design and updating of regulatory documents, including tests for fungal resistance in the list of mandatory.

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Application of waste products of crop processing in the production of building materials for agricultural facilities

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/723/3/032053 ◽

2021 ◽

Vol 723 (3) ◽

pp. 032053

Author(s):

N P Mishurov ◽

M M Voytyuk ◽

P N Vinogradov ◽

O P Machneva ◽

V A Voytyuk

Keyword(s):

Building Materials ◽

Waste Products ◽

Crop Processing

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New Carbohydrate-Based Polymeric Materials

MRS Bulletin ◽

10.1557/s0883769400046492 ◽

1992 ◽

Vol 17 (10) ◽

pp. 54-59 ◽

Cited By ~ 1

Author(s):

Matthew R. Callstrom ◽

Mark D. Bednarski

Keyword(s):

Food Additives ◽

Polymeric Materials ◽

Water Soluble ◽

Natural Polymers ◽

Water Soluble Polymers ◽

Soluble Polymers ◽

Chemically Modified ◽

Stereochemical Control ◽

Natural Polysaccharide ◽

Image Position

The total world production of water-soluble polymers is estimated to be greater than five million tons per year. Water-soluble polymers are most conveniently described according to their origin in three classes (see Structures 1-6):∎ Natural polymers, including starch (1) and cellulose (2);∎ chemically modified natural polymers, including, for example, hydroxyethyl starch (3) and cellulose acetate (4); and∎ synthetic polymers, the most important of which are polyacrylamide (5) and polyvinyl alcohol (6), (commonly composed of both alcohol and acetate groups as shown). The widespread use of these materials is due to both their availability and the range of useful physical properties found in the various natural and chemically modified natural polymers.Of the commercial water-soluble polymers, approximately 50–80% are based on natural polysaccharide materials. One of the primary reasons that these materials find such widespread use is the dramatic response of their properties to changes in their functionality and stereochemistry: chemical modification or the combination of polysaccharides with other polymeric materials has yielded materials whose applications range from explosives to food additives. Although efforts directed at controlling the properties of polysaccharides has resulted in a wide variety of useful materials, we felt control of the composition of carbohydrate-based polymers at the molecular level would provide materials with properties superior to those derived from natural and chemically modified polysaccharide materials.Our approach for the preparation of new carbohydrate-based materials is to use the carbohydrate as a template for the introduction of desired functionality with complete regiochemical and stereochemical control by both chemical and enzymatic methods (Scheme I).

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Setting the Optimal Laser Power for Sustainable Powder Bed Fusion Processing of Elastomeric Polyesters: A Combined Experimental and Theoretical Study

Materials ◽

10.3390/ma15010385 ◽

2022 ◽

Vol 15 (1) ◽

pp. 385

Author(s):

Ruben Vande Ryse ◽

Mariya Edeleva ◽

Ortwijn Van Stichel ◽

Dagmar R. D’hooge ◽

Frederik Pille ◽

...

Keyword(s):

Laser Power ◽

Theoretical Study ◽

Selective Laser Sintering ◽

Polymeric Materials ◽

Thermoplastic Elastomer ◽

Processing Parameters ◽

Operating Conditions ◽

Powder Bed Fusion ◽

Powder Bed ◽

Bed Temperature

Additive manufacturing (AM) of polymeric materials offers many benefits, from rapid prototyping to the production of end-use material parts. Powder bed fusion (PBF), more specifically selective laser sintering (SLS), is a very promising AM technology. However, up until now, most SLS research has been directed toward polyamide powders. In addition, only basic models have been put forward that are less directed to the identification of the most suited operating conditions in a sustainable production context. In the present combined experimental and theoretical study, the impacts of several SLS processing parameters (e.g., laser power, part bed temperature, and layer thickness) are investigated for a thermoplastic elastomer polyester by means of colorimetric, morphological, physical, and mechanical analysis of the printed parts. It is shown that an optimal SLS processing window exists in which the printed polyester material presents a higher density and better mechanical properties as well as a low yellowing index, specifically upon using a laser power of 17–20 W. It is further highlighted that the current models are not accurate enough at predicting the laser power at which thermal degradation occurs. Updated and more fundamental equations are therefore proposed, and guidelines are formulated to better assess the laser power for degradation and the maximal temperature achieved during sintering. This is performed by employing the reflection and absorbance of the laser light and taking into account the particle size distribution of the powder material.

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Using scanned images to estimate salt formation on the surface of cement composites

Vestnik MGSU ◽

10.22227/1997-0935.2020.11.1523-1533 ◽

2020 ◽

pp. 1523-1533

Author(s):

Vladimir T. Erofeev ◽

Victor V. Afonin ◽

Tatiana F. Elchishcheva ◽

Marina M. Zotkina ◽

Irina V. Erofeeva

Keyword(s):

Building Materials ◽

Control Sample ◽

Cement Composite ◽

Operating Conditions ◽

Cement Composites ◽

High Humidity ◽

Grayscale Image ◽

Salt Formation ◽

Scanned Images ◽

Composite Samples

Introduction. An engineering method is proposed for assessing salt formation on the surface of cement composites exposed to adverse operating conditions. The technique is based on the histogram method used to determine the dominant brightness of the half-tone image of scanned cement composites. The criterion for ranking composites is a relative dimensionless value –– a metric obtained by comparing the brightness of a grayscale image with the brightness level of white. Materials and methods. We selected three types of compositions of composites in the amount of 21 items; each of them contains three samples –– a control sample and samples exposed to high humidity and positive temperatures for 15 and 45 days. Each composition is represented by a scanned raster image of the sample surface. The images are further subjected to digital processing using a software program written in the C++ programming language and the OpenCV technical vision library. This allows you to use the available methods and classes to develop algorithms to solve the problem in question and to convert a full-color RGB image to a grayscale image. Such images are used to analyze histograms, which determine the dominant level of brightness to determine the numerical metric for quantifying the salt formation on the surface of cement composite samples on the basis of their scanned images. Results. A description of the software algorithm, used to detect salt formation on the surface of cement composite specimens that have passed performance tests under high humidity conditions at positive temperatures, is presented. The method of ranking cement composite samples using the values of their dominant brightness relative to the brightness of control samples is shown. The comparative analysis of the study is presented in the form of numerical data and explanatory diagrams. Conclusions. Software modeling is employed to demonstrate the expediency of the methodology for the assessment of salt formation on the surface of cement composites and other building materials prone to salt formation.

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Development of Sustainable Alternative Building Materials from Quarry Dust

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.761.181 ◽

2018 ◽

Vol 761 ◽

pp. 181-188

Author(s):

Ehud Cohen ◽

Gabriela Bar Nes ◽

Alva Peled

Keyword(s):

Fly Ash ◽

Building Material ◽

Building Materials ◽

Waste Product ◽

Mining Industry ◽

Chemical Properties ◽

High Volume ◽

Waste Products ◽

Quarry Dust ◽

And Chemical Properties

The main goal of our work is to develop an alternative building material based on “zero waste” objective, thus creating commercially valuable products from materials that are otherwise high-volume waste products. Fine dolomitic quarry dust is a waste product manufactured in several millions of cubic tons each year in the mining industry of Israel. Our study examines a sustainable and useful solution to use this quarry dust (QD) as a part of fly ash based geopolymeric systems. Mechanical, thermal and chemical properties were examined and analyzed.

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Self-Affine Measurements on the Fracture Surface of Plastic Materials by AFM

MRS Proceedings ◽

10.1557/proc-578-357 ◽

1999 ◽

Vol 578 ◽

Cited By ~ 2

Author(s):

E. Reyes ◽

C. Guerrero ◽

V. González ◽

M. Hinojosa

Keyword(s):

Plastic Material ◽

Polymeric Materials ◽

Operating Conditions ◽

Average Roughness ◽

Sem Images ◽

Fracture Surfaces ◽

Material Surfaces ◽

Plastic Materials ◽

Roughness Exponent ◽

Good Agreement

AbstractThe self-aff'me behavior of fracture surfaces of polymeric materials was qualitatively and quantitatively studied. SEM images of fracture surfaces of both polypropylene and polystyrene show Chevron marks at several magnifications. In addition, for polystyrene the mirror and Hackle zones were also observed. For quantitative analysis, the average roughness exponent, ζ, of height profiles generated by AFM images, was estimated by applying the variable bandwidth method. Values of ζ=0.788 and ζ=0.810 were obtained for polypropylene and polystyrene, respectively. These results are in very good agreement with the claimed universal exponent of 0.8 reported in the literature for other non-polymeric materials. By choosing the AFM appropriate operating conditions, measurements of roughness on plastic material surfaces could be performed.

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Activation of Diatomaceous Earth Low-Temperature Plasma

Materials Science Forum ◽

10.4028/www.scientific.net/msf.992.277 ◽

2020 ◽

Vol 992 ◽

pp. 277-282

Author(s):

Michail Bruyako ◽

L. Grigoryeva

Keyword(s):

Low Temperature ◽

Building Materials ◽

Polymeric Materials ◽

Chemical Compounds ◽

Nonequilibrium Plasma ◽

Toxic Chemical ◽

Temperature Plasma ◽

Industrial Buildings ◽

High Sorption ◽

Sorption Characteristics

In residential and industrial buildings, a special air environment is formed, which contains gas shaped toxic chemical compounds. A significant part of such substances comes from finishing polymer containing materials. Virtually all polymeric materials release certain toxic chemical compounds into the air. The methods and methods of air cleaning are different. One of the ways to solve the problem associated with providing the required standards for the quality of indoor air is the development and use of new efficient building materials using aggregates that have a high sorption capacity. The paper presents the results of a study of the effect of low temperature non-equilibrium plasma on the sorption characteristics of aggregates based on diatomite earth. Studies have been conducted on samples of natural diatomite and quartz sand. When activated by low temperature nonequilibrium plasma, the structure changes, which leads to an increase in the sorption characteristics of the samples under study.

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