Microstructural aspects of repairing unalloyed cast steel with around 0.3% carbon content using welding technology

In this work, the results of tests on castings made from unalloyed cast steel, which was repaired using surface padding, have been presented. The purpose of the work was to present the impact of the application of welding technology on the microstructure of cast steels and the dangers related to it. The appearance of a very adverse microstructure was found in the area where the padding occurred. In the light of the presented research, it seems that it is necessary to apply normalizing annealing after the padding of a cast, which will result in a more uniform and fine microstructure of the material being obtained. As a consequence, this will prevent possible operating damage from occurring in the finished products

Vpliv dvostopenjskega staranja in obdelave RRA na abrazivno obrabo med tremi telesi pri zlitini AW7075

The paper presents an analysis of the influence of the heat treatment state on the abrasive wear of the AW7075 aluminium alloy. To determine the hardening state, the material hardness was measured. It was found that hardness is not the only factor that influences this type of wear. For this reason, the influence of the emerging microstructure is also analysed in the considerations. After tribological tests, microscopic observations of surface features were carried out to determine the dominant mechanisms of surface damage. The results were extended by the hardness distribution carried out on the cross-section. There were no changes in hardness that could be related to either strain hardening or structural changes caused by friction

Assessment of the Possibility of Galvanic Corrosion in Aluminum Microchannel Heat Exchangers

As part of the work, three used microchannel heat exchangers from different manufacturers were analyzed. For comparison purposes, the new heat exchanger was also subjected to the NSS salt spray test. The material of the Al-Si system used for brazing, as well as the material of the core, were subjected to electrochemical tests. In laboratory tests, polarization curves were determined for the Al-Si material used for brazing, as well as for the core material. On the basis of exchanger research, it was found that a critical problem in the use of microchannel exchangers is galvanic corrosion occurring in the areas of brazed joints. Electrochemical tests have shown that the Al-Si alloy used for brazing has a lower value of corrosion potential than the core material. The existing potential difference is sufficient for galvanic corrosion. Electrochemical corrosion is initiated in the eutectic structure. The soplid solution is the anode and is particularly susceptible to corrosion, which led to its preferential dissolution in the entire volume of the eutectic mixture

Assessment of the Possibility of Galvanic Corrosion in Aluminum Microchannel Heat Exchangers

As part of the work, three used microchannel heat exchangers from different manufacturers were analyzed. For comparison purposes, the new heat exchanger was also subjected to the NSS salt spray test. The material of the Al-Si system used for brazing, as well as the material of the core, were subjected to electrochemical tests. In laboratory tests, polarization curves were determined for the Al-Si material used for brazing, as well as for the core material. On the basis of exchanger research, it was found that a critical problem in the use of microchannel exchangers is galvanic corrosion occurring in the areas of brazed joints. Electrochemical tests have shown that the Al-Si alloy used for brazing has a lower value of corrosion potential than the core material. The existing potential difference is sufficient for galvanic corrosion. Electrochemical corrosion is initiated in the eutectic structure. The soplid solution is the anode and is particularly susceptible to corrosion, which led to its preferential dissolution in the entire volume of the eutectic mixture

Purpose in Life of Elite Athletes after Spinal Cord Injury

Background: Searching for the meaning of human existence is man’s fundamental orientation. People are free to find meaning in their lives, and while they are not always free to choose the conditions of life, they are free to choose their attitude toward the conditions in which they find themselves. When people experience an unchangeable situation, the most important thing is the attitude they take toward it. This study aimed to identify the sense of meaning in life among elite athletes after a spinal cord injury (SCI) and to analyze the different aspects contributing to this domain. Methods: The study involved five athletes with at least national-level achievements in sports prior to a SCI. The study consisted of an interview using a communicator and filling out two online questionnaires—a personal questionnaire and the Purpose in Life Scale. Results: Analyzing the quantitative results, four participants achieved results indicating a high sense of meaning in life, while one participant achieved a significantly lower result. Conclusions: What affects one’s purpose in life is not so much the objective physical limitation but how much physicality one perceives to have lost as a result of the injury. Elite athletes stay involved in the sporting environment, which prevents the loss of purpose and maintains a sense of meaning at a high level. Both telling the story of your own illness and listening to the stories of others help the process of self-healing

Influence of Drying Method on Some Bioactive Compounds and the Composition of Volatile Components in Dried Pink Rock Rose (Cistus creticus L.)

This study investigates the effects of various drying methods applied to leaves of Cistus creticus L. on the contents of polyphenols and the composition of the volatile fraction. The following four drying methods were used: convection drying at a temperature of 40 °C (CD 40 °C), 50 °C (CD 50 °C), and 60 °C (CD 60 °C); vacuum-microwave (VMD 240 W); combined drying, involving convection pre-drying (50 °C) and vacuum-microwave (240 W) finish drying (CPD-VMFD) as well as freeze-drying (FD). Polyphenols in the dried leaves were determined using chromatography-photodiode detector-quadrupole/time of flight-mass spectrometry (UPLC-PDA-Q/TOF-MS). The contents of odoriferous substances in the dry material were determined by means of head space-solid phase microextraction (HS-SPME) with the use of a gas chromatograph (GC). Thirty-seven polyphenol components including 21 flavonols, eight flavan-3-ols, and eight hydrolyzed tannins in dry Pink Rock Rose material were found for the first time. The highest contents of polyphenols, totaling 2.8 g 100 g−1 dry matter (d.m.), were found in the samples subjected to the CPD/VMFD drying method. Pink Rock Rose subjected to this drying method was characterized by large quantities of odoriferous compounds, mainly eugenol, thymol, and carvacrol, which contribute to its antiseptic properties. By using CPD/VMFD methods, it is possible to obtain fine quality dry material from the leaves of C. creticus

Influence of Physical Fitness and Attention Level on Academic Achievements of Female and Male Military Academy Cadets in Poland

A professional soldier should be characterized not only by high physical fitness but also by high intellectual and cognitive skills. Therefore, it is important to focus on the future commanding cadre-cadets that are educated in military academies. The aim of the study was to look for correlations between the level of physical fitness and attention and academic achievements (AA) in different subjects among cadets studying at military academies. The research group consisted of students of a military academy in Poland, i.e., 228 cadets, including 31 women and 197 men. Correlations between explained and explanatory variables were assessed using Pearson’s correlation. Correlations between AA and somatic parameters and motor components were analysed using optimal regression, using the best subset method. A statistical difference was found between men and women in terms of the level of somatic and motor development; men also performed significantly better in practical military subjects. In the female group, dominant hand strength is a significant determinant of AA in civilian and theoretical military subjects. The findings suggest the need for specialized training aimed at bridging the major differences in physical fitness between men and women by placing greater emphasis on muscle strength development

The Relationship between Cognitive Performance and Quality of Life in Elite Athletes after Spinal Cord Injury

Background: The present investigation was designed to determine cognitive performance and quality of life (QoL) in a group of elite athletes who sustained spinal cord injury (SCI). Methods: nine participants suffering a SCI participated in the study. Different cognitive functions were evaluated through the following tests: COWAT, Digit Span, Stroop color–word and QoL through the WHOQoL-BREF scale. Results: Generally, participants positively assessed their overall quality of life and health status. Although the tests conducted indicate reduced cognitive function among the athletes, it did not affect the reduction in QoL. Single correlations between the results of cognitive tests and QoL could be treated as coincidental. Conclusions: Despite the observed decline in selected cognitive functions, the participants positively assessed their quality of life and physical health.Reduced cognitive functioning could be influenced by the impact of sleep-disordered breathing, pain, depressive disorders and medication. This indicates the need for an individualized approach to define the patient’s deficits, needs and best care. Further studies with a larger group of participants are needed