Characterization of Iron-Ruthenium Bimetallic Catalyst Systems (Methanation, Moessbauer, Zeolite).

Due to the potential of iron-ruthenium bimetallic heterogeneous catalysis in a number of high demand, energy related processes, this study was undertaken to synthesis and characterize a series of bimetallic Iron-Ruthenium alloy and clusters. A material science approach was taken which relies on the physical and chemical characterization of catalyst material itself rather than the classical chemical kinetics investigation of the catalytic reaction. Various methods have been employed for the determination of surface and bulk properties of catalysts during dehydration-hydration, and oxidation-reduction treatments. In the case of the bimetallic systems, the use of (\u2799)Ru and (\u2757)Fe double labelled Mossbauer experiments was most useful. Additional information was obtained from ESCA, X-ray diffraction, and infrared spectroscopy. This array of physical techniques provided complementary details for the complete characterization of the systems of interest. It is known that iron cannot be reduced beyond the ferrous state when ion exchanged in Y-zeolite. Thus, the reduction behavior of iron on zeolite surfaces is considered a classical problem in catalytic research. Several attempts were made to modify the reduction behavior of iron. One approach was to introduce ruthenium into the system to encourage hydrogen spillover which should provide the reactive hydrogen atom as the reducing agent. Utilizing the preparation method designated as Homogeneous-Deposition , the iron was reduced and the formation of hcp iron-ruthenium clusters on the surface of Y-zeolite was confirmed. To elucidate the nature of the interaction between iron and ruthenium and to evaluate the chemical differences of the solid state reaction during the preparation of bimetallic iron-ruthenium, the products formed when ruthenium trichloride is mixed with a variety of iron salts and oxides were investigated. The anions associated with the metal in the initial material influenced the formation and the nature of bimetallic particles. A unique preparative method based on the reaction of a cation exchanged zeolite with a metal-containing coordination complex anion was extended to synthesize the mixed iron-ruthenium cyanide polynuclear complexes directly on the zeolite. Under reduction conditions hcp iron-ruthenium bimetallic alloy was detected. This preparative method could provide an alternative way to stabilize polymetallic particles on zeolites

Frequency of Sports Trauma in Elite National Level Greco-Roman Wrestling Competitions

Background: Trauma is an inescapable part of sports competitions. It occurs more frequently in contact sports such as wrestling. Objectives: The purpose of this study was to determine the frequency of injury in Greco-Roman style wrestling competitions at national level. Patients and Methods: This descriptive epidemiological research included 50 Greco-Roman style wrestlers who participated in national level competitions between the years 2003 and 2008. A questionnaire was completed by each participant, itincluded; the number of injuries to skin, muscle tissue, bones and joints. The reliability of the instrument was evaluated by a test – retest method (r = 0.83, P = 0.0001). Results: The most frequent injuries encountered by the wrestlers were; skin lesions (62%), followed by muscle (22%), bone (9%) and joint (7%) injuries, respectively. Conclusions: Greco-Roman style wrestlers are at high risk of skin injuries.Therefore, they need appropriate instructions on how to avoid injuries and adequate care after their competitions

The Liquid Phase Conversion of Carbon Dioxide to Hydrocarbons Over Ruthenium Catalyst Systems

The purpose of this research project was to evaluate the feasibility of producing hydrocarbons by liquid phase hydrogenation of carbon dioxide. Initial studies dealt with the evaluation of ruthenium (III) chloride over a wide range of reaction conditions. High conversions were observed and were found to vary with catalyst concentration, temperature and time. Conversion of carbon dioxide reached 73% after twenty-four hours at a catalyst concentration of 0.75g/mole of CO2 feed. The hydrogen to carbon dioxide ratio was found to have a significant effect on product distribution and amount of methane produced. For example, low ratios of H2/CO2 gave large amounts of high molecular weight hydrocarbons, while relatively more methane was formed at high H2/CO2 ratios. An attempt was made to determine whether the reaction was taking place in the gas phase or the liquid phase or both. A number of solutions were tested, with sodium hydroxide solutions exhibiting the best results. Since the carbon dioxide feed gas dissolves in this solution immediately to form carbonate species, it is assumed that the hydrogenation reaction takes place through a carbonate species in solution. This mechanism is supported by the observation that the carbonate molarity in solution strongly affected the conversion. The conversion of carbon dioxide over different molarities of sodium hydroxide was observed to exhibit a maximum at the concentration of sodium hydroxide, which give the maximum NaHCO3 concentration. Sodium carbonate and sodium bicarbonate solutions were also tested as starting reagents in the hydrogenation reaction. Conversion was found to be 10.68% for sodium carbonate and 15.88% for sodium bicarbonate, compared with 19% conversion of carbon dioxide under the same reaction conditions. These data suggest that the major part of the hydrogenation reaction takes place through a HCO3 species in solution. The rate of hydrogenation of sodium bicarbonate and sodium carbonate were found to be first order in catalyst concentration. A linear relationship was also found to exist between conversion of carbonate species and temperature in the range of 150-300°C. Three catalyst systems; RuCl3, Ru metal and 1% Ru supported on graphite were tested in the hydrogenation of carbon dioxide over sodium hydroxide solutions. One percent Ru on graphite exhibited the fastest rate at which equilibrium was achieved, with a 76-77% conversion of carbon dioxide to methane, and higher hydrocarbons being observed after 24 hours. Thea activity of Ru metal catalysts was observed to decrease during the course of the reaction, probably because of the loss of active catalyst sites, due to fusing of the catalyst on the surface of the glass liner. The rate of reaction between carbon dioxide and hydrogen over RuCl3 in the gas phase was found to be faster than the rate of this reaction in the liquid phase. In the gas phase reaction, equilibrium was achieved after 24 hours, with 89% conversion of carbon dioxide to methane and higher hydrocarbons, compared with 70% conversion in the liquid phase, under the same reaction conditions. One percent Ru supported on graphite exhibited a faster rate of reaction in the gas phase than in the liquid phase. But the rate of the reaction over Ru metal was faster in the liquid phase than in the gas phase. Table I summarized the comparison between the gas phase and the liquid phase hydrogenation reaction for the three catalytic systems under the same reaction conditions

The role of pre-participation cardiac evaluation in the management of an athlete with premature ventricular contraction-induced cardiomyopathy: a case report.

Background: Premature ventricular contractions (PVCs) are commonly observed during pre-participation cardiac screening in elite athletes. There is an ongoing debate about the clinical significance of PVCs in athletes and whether burden, morphology, or both should be used to differentiate benign PVCs from PVCs suggestive of cardiac disease. Case summary: A 28-year-old male athlete was evaluated as part of the pre-participation screening programme. He was asymptomatic, without specific cardiac signs and symptoms. A 12-lead electrocardiogram showed bigeminy PVCs with infundibular morphology and left ventricular outflow tract origin. Left ventricular dilatation and systolic dysfunction without valvular lesions was detected on echocardiography. Cardiac magnetic resonance imaging showed biventricular dilatation and dysfunction without evidence of myocardial fibrosis or fatty infiltration. A 48 h Holter monitoring showed 75191 PVCs (35% of total beats). Radiofrequency ablation was performed, and post-ablation assessments showed no PVCs with normalized ventricular function and dimension. Discussion: This case demonstrated that a high PVC burden of common morphology does not also represent a benign finding and requires a comprehensive evaluation to rule out any pathological condition. Furthermore, the present case highlights the critical role of pre-participation cardiac evaluation in identifying cardiac disease in asymptomatic athletes

Study of sport trauma in men's sport leagues of Kashan during 2008-9

Background: Athletes participating in sport competitions are faced with the risk of trauma. The purpose of this study was to determine the frequency of trauma injuries in men’s sport leagues of Kashan during 2008-9. Materials and Methods: In this descriptive cross-sectional study, all injuries during sport league competitions were recorded by attending the sport arenas during 2008-9. Results: A total of 160 trauma cases were recorded during 146 events. The highest number of trauma was observed in handball and taekwondo competitions with 45 (25.6%) and 35 (21.9%) cases, respectively. Conclusion: Athletes involved in sport leagues require appropriate training and adequate protection through the use of protective devices to avoid injuries

Spatial memory recovery in Alzheimer's rat model by electromagnetic field exposure

Introduction: Although studies have shown a potential association between extremely low frequency electromagnetic fields (ELF-EMFs) exposure and Alzheimer's disease (AD), few studies have been conducted to investigate the effects of weak magnetic fields on brain functions such as cognitive functions in animal models. Therefore, this study aimed to investigate the effect of ELF-EMF exposure (50 Hz, 10 mT) on spatial learning and memory changes in AD rats. Methods: Amyloid-β (Aβ) 1-42 was injected into lateral ventricle to establish an AD rat model. The rats were divided into six groups: Group I (control); Group II (surgical sham); Group III (AD) Alzheimer's rat model; Group IV (MF) rats exposed to ELF-MF for 14 consecutive days; Group V (Aβ injection+M) rats exposed to magnetic field for 14 consecutive days from day 0 to 14 days after the Aβ peptide injection; Group VI (AD+M) rats exposed to magnetic field for 14 consecutive days after 2 weeks of Aβ peptide injection from 14th to 28th day. Morris water maze investigations were performed. Results: AD rats showed a significant impairment in learning and memory compared to control rats. The results showed that ELF-MF improved the learning and memory impairments in Aβ injection+M and AD+M groups. Conclusion: Our results showed that application of ELF-MF not only has improving effect on different cognitive disorder signs of AD animals, but also disrupts the processes of AD rat model formation. © 2017 Informa UK Limited, trading as Taylor & Francis Group

Effect of Municipal Solid Waste Compost and Sewage Sludge on yield and Yield Components of Black Cumin (Nigella sativa L. )

Abstract In order to investigate the effect of municipal solid waste compost (MSWC) and sewage sludge (SS) on yield and yield components of black cumin (Nigella sativa L.) an experiment was conducted in greenhouse of Faculty of Agriculture, Ferdowsi University of Mashhad. Municipal solid waste compost at 0, 15, 30 ton/ha (C0, C15 and C30) and sewage sludge at 0, 15, 30 ton/ha (S0, S15 and S30) were used in a factorial experiment based on completely randomized design with three replications. Results showed that municipal solid waste compost and sewage sludge and their interaction effects had significant effects on plant height, number of capsule per plant, number of seeds per capsule, number of seeds per plant, seed yield, biomass and 1000 seed weight. Increasing of sewage sludge amount from 15 to 30 ton/ha increased all measured parameters. But with increasing of municipal solid waste compost from 15 to 30 ton/ha, plant height, number of capsule per plant, number of seeds per capsule, number of seeds per plant, seed yield, biomass and 1000 seed weight were decreased. Interaction effects of municipal solid waste compost and sewage sludge showed that yield and yield components in all treatments were increased with the exception of treatment that contained 30 ton/ha municipal solid waste and 0 ton/ha sewage sludge (C30S0). Use of high amounts of municipal solid waste compost (>15 ton/ha) had a detrimental effect on yield and yield components of black cumin. Keywords: Nigella sativa, Municipal solid waste compost, Sewage sludge, Yield and yield component

Epidemiology of sports injuries referring to Kashan University of Medical Sciences Trauma Research Center from 2005 to 2011

Objective Among the injury types, sports ones constitute a considerable proportion of patients who refer to the medical centers. This research was conducted to examine the frequency of sports-related injuries referring to Kashan University of Medical Sciences Trauma Research Center from 2005 to 2011. Methods This was a retrospective research in which existing data from the data bank of Kashan University of Medical Sciences Trauma Research Center were employed. The data were extracted from the main source by SPSS version 16.0. Variables such as age, education, occupation and gender were analyzed. Results The highest proportion of injuries was observed in students (59.4) followed by workers (11.8). Upper and lower extremities were most commonly injured. The most frequent injury was strain (35.4), followed by sprain (27.7). Conclusion The results of this research showed that the majority of the sports trauma occurrs in students; therefore, they need more attention in regard to sports injuries. Preventive measures such as informing the coaches and teachers as well as increasing the students' awareness about the injury risk can decrease the incidences of sports injuries. © 2014 Daping hospital and the Research Institute of Surgery of the Third Military Medical University