Papers by Keyword: Biocide

Abstract: In this study, the dependence of corrosion inhibition and microbial effects of four N-hydroxymethylated amino acids, on their molecular and electronic structure is analyzed using density functional theory calculations. Quantum chemical parameters such as highest occupied molecular orbital energy (E_HOMO), lowest unoccupied molecular orbital energy (E_LUMO), energy gap (ΔE) were calculated at the B3LYP/6-311G++(d,p) basis set. Although no simple relationship between the inhibition performance and the calculated data could be discerned, the comparison of inactivation rate constants with energetic parameters suggested that microbial effects of the compounds can be explained in terms of their side chain disparities.

Abstract: Leathers, which are made from natural fibers, can serve as media for microorganisms to grow. The currently used antimicrobial agents or biocides in the leather industry are harmful to human health and the environment. Therefore, the use of antimicrobial agents should be restricted. This study aims at developing eco-friendly biocides that could substitute for toxic chemicals as it will be tested on vegetable-tanned leather. Due to their large surface area and ability to retain moisture, the vegetable tanned leather has a higher possibility of biodeterioration than other types of leathers tanned by mineral tanning agents. In this work, the natural biopolymer of chitosan was chosen for its ability to inhibit the bacterial growth. The results showed that chitosan coating by impregnation method in drum using chitosan/leather ratio of 1% in formic acid for 2 hours is successfully achieved the bacterial growth inhibition.

Abstract: In recent years, the development of new procedures and solutions in the field of conservation has been very significant. The purpose of this article is to collect the main contributions of nanotechnology, in its multifunctional solutions applied in heritage, to offer a global vision of the state of the matter for both scientists and restaurateurs.Nanomaterials offer some advantages over traditional products, improved compatibility and efficiency and reducing the use of toxic organic solvents for humans and the environment. Solutions have been developed for both inorganic supports and organic supports for artistic, architectural and archaeological heritage. Especially relevant are the advances in consolidation processes, pH regulation and / or cleaning / elimination of alteration products on murals, frescoes or stone and in materials composed of cellulose and collagen.Also, nanotechnology is still a recent science and has yet to answer certain questions about its use protocols and reduce the possible risks to health.

Abstract: Currently, one of the main aspects of health and safety concern to facility owners and supervisors is indoor air quality. Meanwhile, pollution by airborne fungi in these facilities are acquiring more and more consideration due to its possible harmful side effects such as threats to occupiers’ health and damage to building parts and furniture. One of the recommendations to solve these indoor fungi pollution is bioactive compound which can act as a biocide. However, assessment of this compound in the real environment is often time-consuming and impractical. In this study, a bioactive compound, potassium sorbate which is commonly applied in food manufacturing was assessed for its efficiency as a biocide to restrict the growth of an isolated airborne fungus using an in vitro inhibition assay. The fungus was isolated from a new building of tertiary education of computer studies. It was grown on both biocide-incorporated MEA and untreated MEA. The diameter of the fungal colonies was noted time to time. The diameter of the colony of the treated fungus was downsized by 41.25% averagely in comparison with the untreated fungus. It was shown that potassium sorbate can restrict the growth rate of the isolated airborne fungus.

Abstract: This subject used oxidizing biocide C, non-oxidizing biocide Y, and J for single, compound screening, and studied killing performance of them used in municipal middle water. Results indicated that the Y worked best, followed by the J, and C the worst; synergistic biocide P best formula was: J 10 mg/L, and Y 5 mg/L, as this P could be effective in controlling microbial growth.

Abstract: Metalworking fluids (MWFs) are used during machining to prolong the life of the tool, carry away debris, and protect the surfaces of work pieces. During their lifetime they are prone to intensive microbial deterioration. Microbial contamination can be a problem, primarily because of potentional adverse effect to the operators health and effect on a fluid quality, performance and economics. Bactericides are added to control the growth of micro-organisms. The paper deals with possible utilization of ozone for sterilization of MWFs to avoid presence of biocides. There were tested 16 MWFs for their reaction to ozone application in extreme conditions (concentration of MWF 1% (v/v), ozone concentration 15 g hour^-1, application of ozone 4 hours). After, was realized pilot sanitation of selected in-use MWF for elimination of presence bacterias by applying lower concentration of O₃, there were measured few parameters to control the quality of treatment fluid.

Abstract: In this paper, three biocides with different mechanism were chosen to carry static test on screening from single formulation to complex formulation and bactericidal properties. The results showed that the most bactericidal biocide was isothiazolone, and the last was steady chlorine dioxide. The optimum concentration of three biocides in single formulation were isothiazolone10 mg/L, quarternary amine salt 20 mg/L and steady chlorine dioxide 20 mg/L separately. As the best complex formulation, P with optimum concentration of isothiazolone5 mg/L and steady chlorine dioxide10 mg/L, was verified as harmless for environment and also effective inhibition growth of microorganism by dynamic test.

Abstract: Microbial contamination and growth in distillate fuels has been described for seventy years. The consequences have ranged from fouling of filters and injectors, to engine malfunction and damage, fuel gauge malfunctions and aggravated corrosion of engines, fuel tanks, equipment and facilities. The types of microbes present vary with the differences in fuel composition and differences in storage and use conditions. Anti-microbial strategies have traditionally included prevention by ‘good housekeeping’ and ‘fire-brigade’ applications of biocides when there are operational problems. Since 2002, first the aviation industry and later fuel suppliers and some militaries, have used simple on-site microbiological tests to monitor fuel and fuel systems and use the results to take remedial actions before operational problems occur. This paper will review our latest knowledge of microbially influenced corrosion and of the new anti-microbial strategies which are being successfully implemented to prevent it.

Abstract: Scale, corrosion and the and biological growth in industrial water handling processes result in reduced water flow though pipes, reduced heat transfer, and pump failures. Preventative treatments for these problems are based upon chemical compounds that are most often toxic and environmentally persistent. Manufacturers continue to introduce new chemicals and treatment programs onto the market, and old products have been discontinued. Many manufacturers claim that the new chemical and treatments are more environmentally friendly and safer for the plant workers and the users. The U.S. Army Engineer Research and Development Center Construction Engineering Research Laboratory has undertaken a research effort to look at these new chemical treatments. The objective of this work was to develop “green” water treatment chemicals that control biological growth, corrosion and scale while reducing or eliminating the generation of toxic substances during the manufacture, use, and disposal processes.