FEM analysis of protective frame on orchard tractors in rollover case

U ovom radu prikazano je jedno konstruktivno rešenje sigurnosnog rama za voćarske traktore i traktore snage do 65 kW koji se koriste u voćarskoj proizvodnji na nagnutim terenima za mašinsko ubiranje (trešenje) koštičavog voća. Prikazani sigurnosni ram može se montirati na postojeće modele traktora, pre svega domaće proizvodnje. U radu je izvršena analiza naponskih stanja posmatranog sigurnosnog rama u režimu neželjenog slučaja prevrtanja traktora. Uobičajena praksa pri ispitivanju i homologaciji sigurnosnih ramova je da se opterete dvostruko većom silom od težine samog traktora. Analiza sigurnosnog rama vršena je pomoću softverskog paketa SolidWorks korišćenjem metode MKE analize. Ram je opterećen silom od 38,2 kN sa bočne strane i sa gornje strane. Dobijeni rezultati ispitivanja ukazuju na zadovoljavajuću bezbednost.This paper describes a design of the protective frame orchard tractors and tractor power up to 65kW for use in fruit production on sloping ground for mechanical harvesting (shaking) of stone fruits. Shown protective frame can be mounted on existing models of tractors, primarily domestic production. This paper presents an analysis of the stress state of the observed protective frame mode unwanted case overturning tractor. A common practice in the examination and approval of protective frames to be loaded twice the force of gravity of the tractor. Analysis of the protective frame was done using the software package SolidWorks gain and methods of FEM analysis. Ram is loaded with a horizontal and vertical force of 38,2 kN on the side and from above. The results obtained show a satisfactory security

Zaštitna arheološka istraživanja na nalazištu Kalčine šume kod Vladičinog Hana.

Lokalitet Kalčine šume nalazi se u ataru opštine Vladičin Han, na uzvišenju Kastanovac, iznad desne obale Južne Morave i leve obale reke Vrle. Ranijim rekognosciranjem lokaliteta pronađene su kremene sirovine i fragmenti keramike, dok su zbog izgradnje kraka autoputa E-75 na Koridoru 10, kojom je nalazište bilo direktno ugroženo, izvršena prva arheološka iskopavanja. Uz samu zaštitu, cilj ovih iskopavanja bio je u utvrđivanju karaktera i obima lokaliteta.U: Bugarski, I., Gavrilović Vitas, N., Filipović, V. (ur.), Arheologija u Srbiji, projekti Arheološkog instituta u 2015. godini; Beograd: Arheološki institut, стр. 37-40

Analysis of metal ion release from biomedical implants

Metallic biomaterials are commonly used for fixation or replacement of damaged bones in the human body due to their good combination of mechanical properties. The disadvantage of metals as implant materials is their susceptibility to corrosion and metal ion release, which can cause serious health problems. In certain concentrations metals and metal ions are toxic and their presence can cause diverse inflammatory reactions, genetic mutations or even cancer. In this paper, different approaches to metal ion release examination, from biometallic materials sample preparation to research results interpretation, will be presented. An overview of the analytical techniques, used for determination of the type and concentration of released ions from implants in simulated biofluids, is also given in the paper

Effect of welded joint imperfection on the integrity of pipe elbows subjected to internal pressure

Imajući u vidu da lokalna oštećenja smanjuju nosivost i mogućnost deformiranja cjevovoda, analiziran je utjecaj grešaka u zavarenom spoju na integritet cijevnih lukova izloženih djelovanju unutarnjeg tlaka. Ispitivane su greške tipa neprovarenosti, jer su defekti ovog tipa prethodno otkriveni ultrazvučnim ispitivanjem na unutarnjoj površini cjevovoda u hidroelektrani. Trodimenzijska analiza metodom konačnih elemenata je urađena uporabom programskog paketa Abaqus. Određen je utjecaj geometrije defekta u zavarenom spoju (dubina, duljina i položaj) na integritet cijevnih lukova. Također je određen pad nosivosti u slučaju da postoji pukotina na dnu defekta. Ispitan je utjecaj tipa konačnih elemenata (rabljeni su elementi oblika heksaedra i tetraedra).Since local defects reduce the load-carrying capacity and deformation ability of a piping system, an analysis is undertaken to quantify the influence of weld defects on integrity of the pipe elbows subjected to internal pressure. Incompletely filled groove is examined, because this type of defect was previously detected by ultrasonic measurement on the inner surface of the pipeline from a hydro-power plant. Three-dimensional finite element analysis is conducted using Abaqus software package. The influence of weld defect geometry (its depth, length and location) on the elbow integrity is determined. Additionally, decrease of load carrying capacity is determined for the case when a crack has initiated at the bottom of the defect. The influence of finite element type (hexahedral or tetrahedral) is examined

Validation of the osteoporosis quality of life questionnaire QUALEFFO-41 for the Serbian population

Background: Vertebral fractures could lead to reduced physical, social and mental functioning, and loss of personal independence. Therefore, during the treatment of osteoporosis, it has become necessary to examine the changes in everyday functioning, well-being and health related quality of life (HRQOL). To that effect, this study aims to translate, culturally adapt, and validate the Serbian version of Quality of Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO-41) for patients with vertebral fractures. Methods: Nine female patients with osteoporosis participated in the pre-validation study. A validation, case-control study included two groups of female patients: one that consisted of 50 female patients with osteoporosis, and with at least one vertebral fracture, and another one that consisted of 50 control patients with osteoporosis but without fractures. They completed the QUALEFFO-41 and the EuroQol group questionnaire with five dimensions (EQ-5D) twice within a month. The validation study examined internal consistency, concurrent validity, test-retest reliability, sensitivity and specificity. Results: During the pre-validation study, three of the items in the QUALEFFO-41 were slightly changed. Afterwards, during the validation study, the statistically significant differences (adjusted for: age, duration of menopause, current employment and marital status) in the mean values of all domains and total scores between the groups were noted. For the case group, the internal consistency of the QUALEFFO-41 domains and of total questionnaire was above 0.70. The test-retest reliability was tested by the intraclass correlation coefficients (ICC) that were in range 0.87 - 0.96 for the case, and 0.15 - 0.83 for the control group. Correlations between the total scores of the QUALEFFO-41 and the EQ-5D health state value, for both groups were negative and statistically significant (r = -0.78, p lt 0.001 and r = -0.73, p lt 0.001, respectively). The QUALEFFO-41 had a better prediction of the value of HRQOL of cases compared to the generic questionnaire EQ-5D (the AUC difference was 0.099, p = 0.013). Conclusions: The Serbian QUALEFFO-41 version is reliable, valid, sensitive and predictive for examinations of HRQOL in patients with prevalent vertebral fractures and can be used in further studies

Synthesis, structural characterization, biological activity and molecular docking study of 4,7-dihydroxycoumarin modified by aminophenol derivatives

In the present manuscript, three different 4,7-dihydroxycoumarin derivatives were prepared and structurally characterized by crystallographic and spectroscopic techniques in combination with the B3LYP-D3BJ theoretical method. Cytotoxic and antimicrobial activities of investigated compounds were screened against different cell lines and microorganisms. HCT-116 cells were most sensitive to the 3-(1-(2-hydroxyphenyl)amino) ethylidene)-2,4-dioxochroman-7-yl acetate derivative, while the best antimicrobial activity against Bacillus subtilis ATCC 6633 was shown by 3-(1-(2- hydroxyphenyl)amino)ethylidene)-2,4-dioxochroman-7-yl acetate. The molecular docking study for all compounds with important epidermal growth factor receptors (EGFR) was performed. The results indicate that the largest contribution to the binding energy is through conventional hydrogen bonds

Brašno - Kruh '15

Proceedings contains 28 original research articles presented at 8th International Congress Flour – Bread ’15 and 10th Croatian Congress of Cereal Technologists Brašno – Kruh ’1

Analysis of metal ion release from biomedical implants

Metallic biomaterials are commonly used for fixation or replacement of damaged bones in the human body due to their good combination of mechanical properties. The disadvantage of metals as implant materials is their susceptibility to corrosion and metal ion release, which can cause serious health problems. In certain concentrations metals and metal ions are toxic and their presence can cause diverse inflammatory reactions, genetic mutations or even cancer. In this paper, different approaches to metal ion release examination, from biometallic materials sample preparation to research results interpretation, will be presented. An overview of the analytical techniques, used for determination of the type and concentration of released ions from implants in simulated biofluids, is also given in the paper

Analysis of metal ion release from biomedical implants

Metallic biomaterials are commonly used for fixation or replacement of damaged bones in the human body due to their good combination of mechanical properties. The disadvantage of metals as implant materials is their susceptibility to corrosion and metal ion release, which can cause serious health problems. In certain concentrations metals and metal ions are toxic and their presence can cause diverse inflammatory reactions, genetic mutations or even cancer. In this paper, different approaches to metal ion release examination, from biometallic materials sample preparation to research results interpretation, will be presented. An overview of the analytical techniques, used for determination of the type and concentration of released ions from implants in simulated biofluids, is also given in the paper