Journal of Engineering & Processing Management (EPM)
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OPTIMIZATION OF ACTIVE ACIDITY FOR PEPTIDES DERIVATION IN THE PRODUCTION OF FERMENTED MILKS
Get PDFThere are three parameters that influences hydrolyses on milk and fermented milk products. Active acidity (pH) is one of that factors that determines speed of reaction and can influence on specific enzyme substrate. In production of yogurt, hydrolyses is measured by amount of peptides on different pH value. Maximum pH is determined to obtain maximum amount of peptides in yogurt. In order to stop the change in pH value during hydrolysis, the reaction it should be lead out in buffer system. An important parameter for hydrolysis of proteins is the distribution of the weight of the molecule obtained by hydrolysis of peptidite. For milk fermentation were used three different mixture (or combination) of microbiological starter cultures: Lactobacillus delbrueckii subs. bulgaricus and Streptococcus thermophilus; Lactobacillus acidophilus, Bifidobacterium bifidus and Streptococcus thermophilus; Lactococcus lactic subsp. cremoris and Lactococcus lactis subsp. lactis, production by Chr. Hansen’s Laboratories. The task was subsequent measurement of pH value on different temperatures and time incubation of milk by different cultures. Quantity of amino group released in the process of microbiological growing in milk can be easy followed with OPA method, reaction on o-phtaldialdehid in β-merkaptoetanol. Specimens of yogurt were prepared from cow, sheep and goat milk. The measurement of optimal pH with usage three culture were: first mixture on the 430C, fermentation of some pH= 4,3 for 4 hours; second on 370C fermentation some pH= 4,5 for 5 hours and third mixture on 220C and 300C temperature fermentation of some pH= 5,45 for 12 and 8 hours. Amount of total peptides in same type of milk and same pH, same temperature with different mixture of starter culture were different
INFLUENCE OF APPLYING THE DIFFERENT ACIDS FOR ADJUSTING THE DYEBATH pH IN THE PROCESS OF DYEING THE POLYESTER KNITWEAR WITH DISPERSE YELLOW 3
Get PDFThe influence of using formic, oxalic, citric and tartaric acid for adjusting the dyebath pH upon the dyeability of polyester knitwear dyed with Disperse Yellow 3 was investigated. CIELAB coordinates of the knitwear samples dyed with the addition of tested acids were assessed and compared to those dyed with the addition of acetic acid. The differences in dyeabilities obtained with the addition of citric and oxalic acid are acceptable according to both M&S 83A and CMC (2:1) standard and the difference in dyeability obtained with the addition of tartaric acid is acceptable according to CMC(2:1) standard in comparation to the dyeability obtained with the addition of acetic acid, at dye concentration of 1%. For the dye concentration of 2%, acceptable difference in dyeability, in comparation to the dyeability obtained with the addition of acetic acid, according to both M&S 83A and CMC (2:1) standard, was obtained with the addition of tartaric acid
THE INFLUENCE OF POLYACRYLAMIDE (PAA) ON HYDROGEN EVOLUTION REACTION AT THE POLYCRYSTALLINE GOLD
Get PDFThe influence of polyacrylamide (PAA; Mn between 5∙103 and 1.5∙106 gmol-1 ) on hydrogen evolution reaction at the polycrystalline gold in 0.5 M H2SO4 was studied using potentiodynamic measurements (5 mV/s) in the potential range from 0 to -0.6 V/she. It was concluded that formation of protective layer of PAA, adsorbed on the electrode surface, is responsible for inhibition of hydrogen evolution reaction. The further investigations, especially on iron and steel in acid solutions (real corrosion system) confirm the effective inhibition of corrosion by PAA
STATISTICAL PROCESS CONTROL MODEL IN THE DESIGN AND THE DEVELOPMENT OF FABRICS
Get PDFIn this paper the aim was to create a basic model for total quality management in the organization of the textile production, with an emphasis on Statistical Process Control (SPC) in the design and development process that will completely satisfy the requirements, the needs and the desires of the buyers and all the participants in the business relations. The paper deals with a methodology of the process of fabric’s design and development, consisted of two macro stages: 1) development and 2) fabric’s production. The monitoring, the analysis and the verification of the process were done using statistical methods, techniques and tools, with which in the most explicit manner data processing, analysis and presentation are done. This is aimed at continuous process improvement. According to this, a few methods were presented: FMEA method, Pareto and Cause and Effect analysis and X - R control chart
CALCULATION OF RELIABILITY OF TYPICAL COOLING SYSTEM BY DESIGNING OF TREE FAILURE METHOD
Get PDFIn the introductory part we give definitions and relationships to determine the reliability and probability of failure of technical systems. After that, the analysis and calculation of reliability, we proposed method, based on the construction of tree failure in the form of logical structure. The second part was performed to verify the model set on an example of typical cooling system. During this side of event for the loss has taken the minimum required flow of cooling fluid in heat exchanger . On the basis of tree failure in the general analysis is determined by the probability of adverse events, and reliability. At the end of the paper, the estimation of probability of failure, made the estimate, based on weight of i - event, using a typical circuit
HIGH-ENERGY NANOCRYSTALLINE Nd-Fe-B MAGNETIC MATERIALS – SYNTHESIS, CHARACTERIZATION, APPLICATION
Get PDFOne of the most widely used high-energy nanocrystalline permanent magnetic materials are Nd-Fe-B alloys. Current R&D of Nd-Fe-B magnets is focused on three major topics: increase of magnetic energy, improvement of corrosion resistance and reduction of rare-earth content as a way of decreasing prices of final magnetic material with still significant magnetic energy. Utilizing the high sensitivity of microstructure and magnetic properties of Nd-Fe-B alloys to the Nd content, three distinctive types of nanocrystalline alloys have been developed: stoichiometric magnets, Ndrich (decoupled magnets) and magnets with reduced Nd content (nanocomposite magnets). In the presented paper a brief overview of each type of Nd-Fe-B alloy is given, processing methods are outlined and several high technology application examples are presented. Based on experimental results obtained using modern high resolution characterization techniques optimal processing conditions for the selected synthesis method are presented. Trends and challenges in future R&D of magnetic nanomaterials are discussed
RED MUD AS BASE FOR FERROUS CEMENT SYNTHESIS
Get PDFConsumption of red mul, of huge ballast in alumina production is nightmare for scienists who are working in the area of industrial metallurgi, one dey will become reality. Among other things of cement industry is going to help regrading assortment of products and diversity of raw material base. In this document, theoretical bases of the mentioned attempt are presented, as well as calculated indicators of charge preparation and obtaining klinker which would has and lot of good quality characters for special use. Certain difficulties, due increased content of alkali and harder sintering of this material mixture, are not insuperable
RESONANT IR ABSORPTION IN NANOTHIN MOLECULAR FILMS
Get PDFThis paper presents results of theoretical research in changed optical properties due to the presence of boundaries and changes of boundary parameters in nanofilm-molecular crystals. The energy spectrum of excitons and their spatial distribution along the axis limits (in layers) were found through analytical and numerical calculations. The relative permittivity of these ultrathin dielectric films was determined and the influence of boundary parameters on occurrence of discrete (by frequencies) and selective (per layers) absorption was analyzed. We found conditions for the appearance of the smallest number of resonant absorption peaks (absorption lines) in the border surfaces of the observed film structure
ZERO EMISSIONS CONCEPT
Get PDFWhile proposed concepts to minimize, reuse and recycle wastes have generally, not solved the negative effects on environment, zero emissions concepts have arisen. The term Zero Emissions attracted special attention, as it is easily comprehensible and does not require translations. This concept is drawing mounting interest all around the world. In the recent years since the amount of waste generated is increasing, the demand of energy is pressed, and availability of natural resources is limited, the use of waste has become one of the main field of interest for researchers. This concept foreseen input streams to an industrial complex being used in the final products or converted into value added inputs for other industries or processes. It implies the optimization throughout an integrated system of processes and requires the industries to redesign manufacturing processes to resourcefully use both raw material within the process and waste towards the aim of sustainability. That implies exploitation of waste that can be brought to at sustainable levels in closed circle processes, ideally, the integrated process produces no wastes. Waste can be a resource if it is put in the right place
FORMATION OF CARCINOGENIC SUBSTANCES DURING HEATING OF FOODS
Get PDFHeating of foods induces chemical reaction pathways that are not only leading to desired compounds (e.g. aroma and taste active) but also to degradation products that can pose a cancer risk. Especially the Maillard reaction is known for the formation of carcinogenic compounds in some instances. Recently, it was described that the uptake of oxidised lipids can also lead to cancer. However, the active principle is not yet identified and it has been suggested that the aldehydes, peroxides, or epoxides are the chemical structures that induce the changes of the DNA. From the Maillard reaction a number of different potentially toxic substances are formed which comprises the heterocyclic amines, acrylamide, and the furan derivatives. During the last few years a biochemical mechanism was described which activates the furan derivatives (e.g. furfuryl alcohol, HMF) which are then able to form DNA-adducts. Heterocyclic amines are formed from a reaction of amino acids with carbohydrates and creatinine. In contrast to this reaction acrylamide is formed from asparagine in the presence of sugars. The formation of HMF is not so much dependent on high temperatures as the heterocyclic amines or acrylamide. It is also formed during storage of carbohydrate rich foods. Other furan derivatives like furfuryl alcohol need higher temperatures as well.The concentration of these compounds covers a wide range from low ng/g in the case of heterocyclic amines to µg/g in the case of acrylamide and mg/g in the case of HMF and other furans. This means that even if the carcinogenic potential of the furans is low the high concentration and ubiquitous occurrence results in a chronic and high exposure which can also contribute significantly to the cancer risk of heated foods