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Praškasti proizvod namenjen za pripremu proteinskog napitka na bazi sojinog mleka sa dodatkom probiotskih bakterija-SoPro-Shake
No full textPrikazano tehničko rešenje predstavlja inovaciju u obliku novog funkcionalnog proizvoda –
proteinskog funkcionalnog napitka u formi praha sa dodatkom probiotika koji obiluje
nutrijentima, bioaktivnim materijama i fiziološkim komponentama objedinjenim u kompaktnu
porciju ekološke ambalaže koja daje potrošaču mogućnost brzog i lakog rukovanja. Novi
proizvod kreiran je sa ciljem da se potrošačima u Republici Srbiji omogući unos nutritivno
vrednog napitka na lak i pristupačan način. Pri izboru sastojaka, ali i ambalaže vodilo se računa o
ekonomičnosti, ekološkom aspektu, ali i o senzorici. Tehničkim rešenjem je pokazano da je
moguće kreirati ovakav napitak u formi praha sa dodatkom probiotika koji je sa proteinima
bundeve deklarisan kao visokoproteinski proizvod jer je više od 20% energetske vrednosti
poreklom iz proteina. Sa druge strane, ukoliko se priprema sa pogačom suncokreta proizvod je
bogat vlaknima i sadrži preko 6g vlakana u 100g proizvoda.Predložena kategorija tehničkog rešenja je M82
Praćenje i otklanjanje uzroka korozije i perforacije zida kod izmenjivača toplote napravljenih od nerđajućeg čelika aisi 316L
No full textThe Technical Solution includes tests and recommendations to prevent corrosion and wall perforation of heat exchangers made of AISI 316L stainless steel. The heat exchanger consists of two corrugated tubes, made by the process of cold forming, which are placed concentrically inside each other. A liquid, in this case water, circulates between those tubes. Corrosion occurs on the inner surface of the outer corrugated tube, and its outer side is covered with polyurethane -foam in order to insulate the heat exchanger. Before putting the heat exchanger into operation, the working surface of the tubes in the Client's facility is passivated using a commercial solution for the passivation of stainless steel, at room temperature. In order to test the provided samples, the chemical composition of stainless steel, the pH value of the solution of the delivered powder taken from the reservoir, electrochemical tests of stainless steel, a test with potassium ferri-cyanide, and a test with a contrast penetrant were performed. The chemical composition of the provided samples was in accordance with the standard prescribed values, however, the content of the main alloying elements (Cr, Ni, and Mo) in the stainless steel was at the lower permissible limit according to the ASTM A240 standard. For a higher safety factor, the tests were performed in a solution of 200 ppm NaCl, which is approximately 1000 times more concentrated than the fluid under operating conditions. The pH value of both, the NaCl solution without dissolved powder and NaCl solution with dissolved powder that was deposited on the reservoir wall was measured. The composition of the powder sample was determined by the FTIR method. The values of polarization resistance (Rp), the value of the impedance modulus (ZMod) at low frequencies (1.25 mHz), and the values of corrosion current densities (jcorr) were determined, as indicators of the resistance of stainless steel to general corrosion. The pitting potential values (Epit) and the Epit-Ecorr difference were also determined, as an indicator of the resistance of stainless steel to pitting corrosion. In addition, the degree of sensitization (susceptibility of stainless steel to intergranular corrosion) was determined using the DL EPR method. Besides, a test with potassium ferri-cyanide as well as a test with a contrast penetrant were performed. The potassium ferri-cyanide test was performed in order to detect the presence of free iron on the surface of stainless steel. The contrast penetrant test was used for better visual detection of damage on the metal surface. As a result of these investigations, technological recommendations were given to prevent the occurrence of localized forms of corrosion and perforation of corrugated tubes made of stainless steel AISI 316L, which is used for the production of heat exchangers in the Client's plant. 7 The solution was sold to the Customer in 2024, and from October 2024 it is implemented in the facilities of the Customer, TING DOOEL, which confirmed the implementation of this Technical Solution in their business.Kategorija M81
Permanentno termovizijsko praćenje skladišta uglja i drugih zapaljivih materijala u cilju prevencije samozapaljenja
No full textPreliminarni rezultati na konkretnom skladištu potvrdili su i nadmašili očekivanja i
pokazali izvanrednu efikasnost termovizijskog nadzora skladišta uglja. Ovde treba naglasiti i
izuzetnu visoku održivost predloženog rešenja, jer se upotrebom ovakvog rešenja mogu
ostvariti i i daleko dugoročnije primene u odnosu na samu primenu na odgovarajućoj lokaciji.
Tako na primer se na osnovu prikupljenih istorijskih podataka u okviru sistema mogu razviti
odgovarajući prognostičarski sistemi i omogućiti primenu prediktivne analitike i metoda
mašinskog učenja nad tim podacima čime se dodatno mogu poboljšati različiti uslovi rada u
posmatranom domenu. Takođe, kombinacijom ovih podataka, analiza i dobijenih prediktivnih
vrednosti sa niza različitih lokacija može se ostvariti bolji uvid u same procese i uslove koji
dovode do samog samozapaljenja čime se mogu omogućiti značajnija unapređenja u ovom
polju.M85 „Novo tehničko rešenje u fazi realizacije
Determination of fracture mechanics parameters on pipe ring notch tensile (prnt) specimens
No full textDetermining the parameters of fracture mechanics is a key segment in assessment and enhancement of the safety and longevity of materials and structures, especially when they are exposed to extreme load conditions in the presence of damage. In this work, one group of such structures is considered - thin-walled pipelines, which are used in practically all processindustry branches. Since the standard procedures prescribed by ASTM and ISO standards are not the most relevant if one of the criteria is not met, which is the testing of materials in plane strain state, it is necessary to develop a complete procedure for testing fracture mechanics parameters for thin-walled pipelines. This paper will present the results of experimental and numerical analysis of fracture mechanics parameters determined by a non-standard procedure for PRNT (Pipe Ring Notched Tensile) ring-shaped specimens, introduced in [1] through analysis of 3D printed polymer rings. The specimens are examined using a specially designed tool on a universal machine for testing the mechanical characteristics of materials with a working capacity of 100 kN and a sensitivity of 1 N. The parameters related to the displacement of points on the samples were measured and calculated based on the results obtained by the digital image correlation method (DIC). In this work, the main topic is determination of the values of previously mentioned fracture mechanics parameters; since the specimens are not standard, finite element software package Simulia Abaqus is applied for determination of these values. On the tested geometries, the ratio of the width of the sample to the initial length of the sharp stress concentrator (a sharp notch or a pre-crack) was varied (a0/W = 0.4 – 0.6). Also, a wider range of this ratio is used for one of the geometries, in order to extend the application range. Since J-integralvalues are typically calculated as sum of the elastic and plastic part, the main parameters which are needed are: stress intensity factor KI, plastic geometry factor η and crack propagation correction factor γ. Generally, it can be said that the obtained parameter values showed almost linear dependence on the ratio a0/W and a slight difference in the values due to varying dimensions such as width, wall thickness and cross-section of the model. This consistency indicates a good potential of the procedure and the possibility of practical implementation on the thin-walled pipelines
Bioengineering for creating biomimetic microenvironments: bioreactors and biomaterials
No full textNTRODUCTION: Millions of patients are still awaiting new therapies as the traditional modelsrelyon monolayer cell (2D) cultures and in vivostudies, which havenumerous limitations resulting in misleading conclusions. Consequently, there is a burning need for the development of alternative 3D models able to accurately mimicthe complexity of human diseases.This research aim is to create microenvironments based on biomimetic bioreactors and alginate hydrogels as cell carriers for reliable disease research and drug screening. ...ExcellMater Conference 2024: Innovative Biomaterials for Novel Medical Devices, Belgrade, Serbia, April 10-12, 202
Plasma surface modification of textiles for application of natural dyes
No full textGenerally, clothes are constructed from woven or knitted fabrics, which can be made from natural or synthetic fibers or their mixtures. Natural fibers are characterized by their hydrophilicity, antistatic properties, and pleasant touch. Their ability to absorb water makes them susceptible to the action of microorganisms that change the textile's quality, resulting in an unpleasant odor and loss of color and strength. Wearing such clothes can also cause irritation and allergies. Besides natural materials used in textile industry, synthetic materials characterized by hydrophobicity and high mechanical properties are largely used for the production of sports clothing. In order to dye manmade fibers, synthetic dyes must be employed, which are harmful to the environment and can cause allergic reactions in humans. The dyeing of natural and synthetic materials with medicinal plant extracts improves the comfort and functionality of clothing. Plant extracts give color to textiles, and serve as antiallergic, deodorizing, and antimicrobial compounds, which is especially important when it comes to clothing used in medicine and sports. In order to promote the binding of components of medicinal plant extracts, certain modifications of the textile surface are required at the microscopic level, which can affect the wetting and dyeing ability. Plasma treatment can be considered as an alternative to conventional fiber modification procedures due to its appropriate environmental and economic acceptability
Spatio-temporal distribution of the calanoid copepod genus Centropages in relation to environmental factors in the southern Adriatic Sea (NE Mediterranean)
No full textSpatial and temporal variability of Copepoda was studied at four stations in the Bay of Boka Kotorska and five stations in the open waters of the South Adriatic Sea in 2008. The research area included three sectors differing in geographical and hydrological conditions: The Bay of Boka Kotorska, the estuary of the Bojana river (both with the typical neritic Copepod fauna), and offshore waters of South Adriatic Sea (with the pelagic species). Four species from the genus Centropages Kröyer, 1849 were registered: C. typicus Kröyer, 1849, C. kröyeri Giesbrecht, 1893, C. violaceus (Claus, 1863) and C. ponticus Karavaev, 1895. Only one of the species, C. typicus, was encountered at all nine stations. By examining the seasonal distribution and abundance of specimens, as well as the ecological properties of the researched area, we observed particular behavioural pattern in distribution and abundance of certain species that had not been described previously. The conclusion is that the seasonal differences in the horizontal distribution are associated with the dynamics of the hydrographic conditions of the South Adriatic Sea. Significant relationships have been reported between C. kröyeri abundance and the temperature and dissolved oxygen concentration, and C. typicus abundance and pH factor.Répartition spatio-temporelle des copépodes calanoïdes du genre Centropages en relation avec
les facteurs environnementaux dans le sud de la mer Adriatique (NE Méditerranée). La variabilité spatiale et temporelle des copépodes a été étudiée dans quatre stations de la baie de Boka Kotorska et cinq stations dans les eaux du large de la mer Adriatique Sud en 2008. La zone de recherche comprenait trois secteurs présentant des conditions géographiques et hydrologiques différentes : la baie de Boka Kotorska, l’estuaire de la rivière Bojana (tous deux avec la faune typique des copépodes néritiques) et les eaux au large de la mer Adriatique du Sud (avec les espèces pélagiques). Quatre espèces du genre Centropages Kröyer, 1849 ont été enregistrées. C. typicus Kröyer, 1849, C. kröyeri Giesbrecht, 1893, C. violaceus (Claus, 1863) et C. ponticus Karavaev, 1895. Une seule de ces espèces, C. typicus, a été observée dans les neuf stations. En examinant la répartition saisonnière et l’abondance des spécimens, ainsi que les propriétés écologiques de la zone étudiée, nous avons observé un comportement particulier dans la répartition et l’abondance de certaines espèces qui n’avaient pas été décrites précédemment. La conclusion est que les différences saisonnières dans la distribution horizontale sont associées à la dynamique des conditions hydrographiques de la mer Adriatique Sud. Des relations significatives ont été enregistrées entre l’abondance de C. kröyeri et la température et la concentration d’oxygène dissous, et l’abondance de C. typicus et le pH
Supplementary material for the article: Perović, M. N.; Knežević Jugović, Z. D.; Antov, M. G. Heat-induced nanoparticles from pumpkin leaf protein for potential application as β-carotene carriers. Future Foods 2024, 9, 100310. https://doi.org/10.1016/j.fufo.2024.100310
Get PDFNanoparticles prepared by heat treatment of protein from pumpkin leaves were evaluated as potential carriers of β-carotene. White protein fraction was recovered from green juice produced by pressing the leaves, with the step of enzyme-assisted extraction (green protocol) or without it (conventional protocol). Heat treatment of white protein fractions from conventional and green protocols at 90 °C and pH 9.3 during 20 min induced formation of nanoparticles with peak diameter 18 nm and 21 nm, respectively. Due to heating, portion of β-sheets in nanoparticles from both native protein fractions decreased by approximately 15 %, associated with an increase in surface hydrophobicity-to-area ratio. Quenching constant of β-carotene for nanoparticles was increased nearly 100 times by heating the white protein fraction recovered in green protocol. Native white protein fraction from conventional protocol and corresponding nanoparticles exhibited high ability to bind β-carotene, with quenching constant 3 × 105 L/mol and 3.3 × 105 L/mol, respectively. White protein fraction from pumpkin leaves appeared to be a suitable substrate for the fabrication of nanoparticles by heat treatment, with potential application as β-carotene nanocarriers in food matrices.Related to: [https://technorep.tmf.bg.ac.rs/handle/123456789/7257]Supplementary material for: [https://doi.org/10.1016/j.fufo.2024.100310
Failure analysis of welded joint with multiple defects by extended Finite Element Method and Engineering Critical Analysis
No full textFailure analysis of welded joint with multiple defects was performed taking into account the effect of all defects, not just a dominant one. Four cases of multiple defects in welded joint under the uniaxial tensile loading were investigated using extended Finite Element Method. Two-dimensional Finite Element Models were made according to the tensile specimens with initial crack located in a critical area of welded joint. For each multiple defects case, numerical simulation was performed with three initial crack depth. Engineering Critical Analysis was made using Failure Assessment Diagrams for each defect that was determined as critical for its welded joint case. Numerical simulation showed that the geometry of the most prominent one from a point of view of structural integrity. It was concluded that the vertical misalignment in combination with a secondary defect, had the most adverse effect which can lead to failure of welded structure
Berries Pomace Valorization: From Waste to Potent Antioxidants and Emerging Skin Prebiotics
No full textFruit pomaces are agro-industrial by-products obtained in large quantities by the juice production industry, hence their reutilization is a suitable way to minimize environmental impact by transforming them into different value-added products. Considering the wide abundance and bioactive potential of berries pomaces, raspberry, strawberry, blackcurrant, and chokeberry pomace were chosen to examine and compare polyphenol content, antioxidant activity, and skin prebiotic capacity of their extracts. Extracts of 5.28 to 13.39 mg GAE ⋅ g−1 DM total polyphenol content were obtained, with significant differences in polyphenol abundance between classes. Relative antioxidant capacity index and global antioxidant score revealed that the blackcurrant pomace extract exhibited the highest antioxidant capacity. Staphylococcus epidermidis growth was promoted by lower extract concentrations, while higher concentrations showed inhibitory effects. On the other hand, Staphylococcus aureus was inhibited more strongly and no stimulation was detected in the tested concentration range (.025–.1 mg GAE ⋅ mL−1). In co-cultured experiments, a S. aureus/S. epidermidis rebalancing effect was proven for all tested extracts, whereas the best prebiotic capacity of 2.84 was achieved at.05 mg GAE⋅ mL−1 of raspberry pomace extract. In conclusion, berry pomace extracts could be valorized by extraction of their phytochemicals which are potent antioxidants and emerging prebiotics for topical application