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EN
Purpose: The aim of the work is to analyze the accidents at work in the selected manufacturing enterprise from automotive industry. Methodology: The research includes three workplaces: warehouseman, machine operator and transport worker. The accidents investigation was based on the methodology and work accident model developed by the EU Statistical Office (Eurostat) as a part of the European Statistics on Accidents at Work (ESAW) project. This model includes three phases: pre-accident, accident and post-accident. Findings: In the years 2019-21 in the selected workstations there were noted 25 accidents at work (12 accidents in 2019, 8 accidents in 2020 and 5 accidents in 2021). The accidents at work were analyzed taking into consideration: the type of injury and the part of body injured, the physical activity at the time of the accident, an event that is a deviation from normal practice, and causes of the accident. Practical implications: The results of the analysis allow to introduce suitable corrective actions, e.g. 5S method, ‘shoptalks’ about occupational health and safety, suggestion submission program, etc., what influenced the reduction of accidents at work in 2020 and 2021. Originality/value: The use of statistics for accident at work allows to evaluate the safety state in an enterprise. The statistics also allows to formulate various factors that can be used to evaluate accident rates, workstations with a special risk of accident, realization of various comparative analyzes in the area of investigation of accident situations, and corrective actions towards hazards reduction.
EN
In this work, conversion coatings based on nitrates Ca(NO 3) 2 and Zn(NO 3) 2 were produced on the surface of MgZn49Ca4 to protect against corrosion. The main aim of this study was to prepare dense and uniform coatings using a conversion method (based on nitrates Ca(NO 3) 2 and Zn(NO 3) 2) for resorbable Mg alloys. The scientific goal of the work was to determine the pathway and main degradation mechanisms of samples with nitrate-based coatings as compared with an uncoated substrate. Determining the effect of the coatings produced on the Mg alloy was required to assess the protective properties of Mg alloy-coating systems. For this purpose, the morphology and chemical composition of coated samples, post corrosion tests and structural tests of the substrate were performed (optical microscopy, SEM/EDS). Immersion and electrochemical tests of samples were also carried out in Ringer’s solution at 37°C. The results of immersion and electrochemical tests indicated lower corrosion resistance of the substrate as compared with coated samples. The hydrogen evolution rate of the substrate increased with the immersion time. For coated samples, the hydrogen evolution rate was more stable. The ZnN coating (based on Zn(NO 3) 2) provides better corrosion protection because the corrosion product layer was uniform, while the sample with a CaN coating (based on Ca(NO 3) 2) displayed clusters of corrosion products. It was found that pitting corrosion on the substrate led to the complete disintegration and non-uniform corrosion of the coated samples, especially the CaN sample, due to the unevenly-distributed products on its surface.
3
Content available remote Mechanical and corrosion properties of Mg68-xZn28+xCa4 (x=0,2,4) metallic glasses
EN
Metallic amorphous alloys, which consisted of the biocompatible elements such as Ca, Mg and Zn, can be used as potential resorbable materials for short term orthopedic implants [1,2]. The concept of resorbable metallic implants is based on combination of two factors: good bearing capacity, sufficiently high mechanical strength and stable implants geometry, invariable during concrescence of bone, and controllable corrosion rate (dissolution rate). Therefore, the following criteria on Mg-based metallic glass for resorbable implant were chosen: Rc > 160 MPa [3], H2 ≤ 1ml/h [4] and Vcorr ≈ 0.01 - 0.1 mm/year [5]. The glass-forming ability (GFA), volume of evolved hydrogen, corrosion rate, compression strength and hardness of Mg68-xZn28+xCa4 (x=0,2,4) metallic glasses were examined. Results of corrosion studies and mechanical properties tests were compared with assumed criteria. Results of corrosion tests showed that the corrosion rate (Vcorr) and the volume of released hydrogen decreased with the increase zinc concentration in the tested alloys. For the Mg66Zn30Ca4 amorphous alloy with a diameter of 2 mm, the highest hardness about 300 HV and the compressive strength about 400 MPa were determined.
PL
Stopy metali o strukturze amorficznej, które składają się z biokompatybilnych pierwiastków, takich jak Ca, Mg i Zn mogą być rozpatrywane jako potencjalnie resorbowalne biomateriały do krótkotrwałych implantów ortopedycznych [1,2]. Koncepcja resorbowalnych implantówmetalicznych opiera się na połączeniu dwóch czynników: dobrej nośności, odpowiedniej wytrzymałości mechanicznej i stabilnej geometrii implantów, niezmiennej w trakcie wzrostu kości i kontrolowanej szybkości korozji (szybkości roztwarzania). W związku z tym wybrano następujące kryteria dla szkła metalicznego na osnowie magnezu, rozpatrywanego jako materiał na resorbowalny implant: Rc> 160 MPa [3], H2 ≤ 1 ml/h [4] i Vcorr ≈ 0,01 - 0,1 mm/rok [5]. W ramach tej pracy zbadano zdolność do zeszklenie (GFA), objętość wydzielonego wodoru podczas zanurzenia w roztworze Ringer’a, szybkość korozji, wytrzymałość na ściskanie i twardość szkieł metalicznych Mg68-xZn28+xCa4 (x = 0,2,4). Wyniki badań korozyjnych i właściwości mechanicznych zostały porównane z założonymi kryteriami. Wyniki badań korozyjnych wykazały, że szybkość korozji (Vcorr) i objętość uwolnionego wodoru zmniejszyły się wraz ze zwiększeniem stężenia cynku w badanych stopach. Dla amorficznego stopu Mg66Zn30Ca4 o średnicy 2 mm wyznaczono najwyższą twardość około 300 HV i wytrzymałość na ściskanie około 400 MPa.
PL
W artykule opisano możliwości wykorzystania narzędzi BIM w procesie projektowania obiektów inżynierskich na przykładzie kładki dla pieszych z drewna modyfikowanego. Narzędzia BIM pozwalają na usprawnienie działań projektowych, zwłaszcza przez algorytmy parametryzacji geometrii. Obecnie badane procesy funkcjonalizacji drewna pozwalają na poprawę jego właściwości mechanicznych, czyniąc go konkurencyjnym materiałem, szczególnie biorąc pod uwagę aspekty ekologiczne.
EN
The article describes capabilities of using BIM tools in the bridges design process based on pedestrian bridge of modified wood. BIM tools allow to improve designing activities, especially through geometry parametrization algorithms. The processes of wood functionalization, which are currently being researched, allow improving it's mechanical properties, what makes wood competitive material, especially considering ecological aspects.
EN
The Mg-Zn-Ca-(Cu,Au) alloys were considered as resorbable materials for orthopedic short- term implants. The aim of this paper was to determine the influence of Au and Cu addition on corrosion properties of Mg69Zn25Ca5Au1, Mg69Zn25Ca5Au0.5Cu0.5 and Mg69Zn25Ca5Cu1 metallic glasses. The analysis of corrosion results allowed to describe the influence of 0.5 and 1 at.% of Au and Cu on the corrosion resistance in artificial physiological fluid. The Mg69Zn25Ca5Au0.5Cu0.5 and Mg69Zn25Ca5Cu1 metallic glasses exhibit lower corrosion resis-tance in comparison with Mg69Zn25Ca5Au1 alloy. The increase of Cu content caused the increase of hydrogen evolution volume and the high cathodic activity. The Mg69Zn25Ca5Au1 metallic glass shows the decrease of hydrogen evolution volume and manifests the low corrosion current density and the high polarization resistance, indicating the high corrosion resistance.
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