71 research outputs found

    Catalytic decomposition of 2-chlorophenol using an ultrasonic-assisted Fe3O4-TiO2@MWCNT system: Influence factors, pathway and mechanism study.

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    As a reusable sonocatalyst, magnetically separable Fe3O4-TiO2@MWCNT (FMT) was synthesized by an ultrasound-assisted wet impregnation method and was evaluated in the removal of 2-chlorophenol (2CP). Physical and chemical properties of the catalyst composite materials were investigated by all catalysts were systematically characterized using Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive X-ray Analysis (EDX), Dynamic light scattering (DLS), and N2-physisorption. The efficiency and kinetics of 2CP removal by FMT-assisted sonocatalysis (FMT-US) was systematically investigated under various operational parameters i.e. pH, FMT and 2CP concentration, temperature and ultrasonic power. The results indicated that 0.4gL-1 FMT dosage, pH 5, temperature of 35°C as well as 50 w ultrasound power are the most favorable conditions for the degradation of the 2CP. Furthermore, both of the superoxide and hydroxyl radicals were produced in the reaction, however, superoxide radicals were assumed to be the dominating reactive species for the 2CP degradation, according to the scavenging tests and electron paramagnetic resonance tests. Moreover, the FMT catalyst exhibited a high reusability and stability in the US/FMT system during the five repetitive experiments. The intermediate products were identified by GC-MS, thereby a possible degradation pathway is proposed. The chemical oxygen demand (COD) and corresponding total organic carbon (TOC) removal efficiencies were 64.9% and 56.7%, respectively. Finally, toxicity tests showed that the toxicity of the solution increased during the first 5min and then decreased significantly with the progress of the oxidation. The mechanisms of ultrasound irritation enhanced FMT activation were also proposed. Copyright © 2017 Elsevier Inc. All rights reserved

    Energy-Efficient Timing Assignment of Tasks to Actors in WSANs

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    Minimizing make-span and maximizing remaining energy are usually of chief importance in the applications of wireless sensor actor networks (WSANs). Current task assignment approaches are typically concerned with one of the timing or energy constraints. These approaches do not consider the types and various features of tasks WSANs may need to perform and thus may not be applicable to some types of real applications such as search and rescue missions. To this end, an optimized and type aware task assignment approach called TATA is proposed that considers the energy consumption as well as the make-span. TATA is an optimized task assignment approach and aware of the distribution necessities of WSANs with hybrid architecture. TATA comprises of two protocols, namely a Make-span Calculation Protocol (MaSC) and an Energy Consumption Calculation Protocol (ECal). Through considering both time and energy, TATA makes a tradeoff between minimizing make-span and maximizing the residual energies of actors. A series of extensive simulation results on typical scenarios show shorter make-span and larger remaining energy in comparison to when stochastic task assignment (STA), opportunistic load balancing (OLB), and task assignment algorithm based on quasi-Newton interior point (TA-QNIP) approaches is applied

    The Effect of Foliar Application of Silicon, Calcium, and Potassium Fertilizers on Yield and Some of the Agronomic and Physicomechanical Traits of Hordeum Vulgare

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    IntroductionFood security is one of the basic needs of any society. Studies have been conducted on the foliar application of elements, especially silicon, calcium, and potassium, to reduce the adverse environmental effects on the physico-mechanical properties of cereals and improve their growth and development in order to maintain food security. Lodging, which is caused by a decrease in the mechanical properties of the plant stem's flexural strength, is characterized by bending or fracture that changes the angle of the grain stem from the vertical position. Due to the important factors involved, an important aspect of performance is directly and indirectly related to the occurrence of fungal diseases and nutrient-related issues affecting the physico-mechanical properties of the plant, such as flexural strength. The efficacy of silicon, calcium, and potassium in addressing these concerns is notable.Materials and MethodsThis research was conducted at the research farm of the Faculty of Agriculture, Shahroud University of Technology, located in Bastam. The seeds of the Reyhan cultivar, a high-yielding and early spring-type barley plant suitable for regions with mild winters and short springs, were used in this study. Planting operations followed agricultural principles, and irrigation was carried out using atmospheric and ridge methods. The first irrigation took place after planting, and subsequent irrigations were performed at eight-day intervals. Harvesting was done manually at the end of the growing period, specifically 115 days after planting.The experiment followed a factorial design and utilized a randomized complete block design with three replications. On July 11 (115 days after planting), a harvest sample measuring 50 cm2 was taken from each experimental plot, accounting for the margins, to determine the yield.For the barley stem bending test, a three-point bending test was conducted using a material testing machine. The probe applied a loading speed of 5 mm.min-1. A specially designed jaw was used for the barley stem cutting test, taking into consideration the characteristics of the barley plant. The incision test was performed on the second median, and the loading speed was set at 20 mm.min-1.Results and DiscussionThe main axial stem serves as a storage organ, supporting the filling grains through stock re-transference. A desirable trait is having a higher dry weight in the stem. Among the treatments, foliar application of 6 mM calcium chloride, along with sodium silicate at all three levels and spraying with 12 mM silicon at concentrations of 150 and 300 mg.L-1, showed statistically superior results.Stem diameter is an important attribute related to plant strength, stability, resistance to lodging, and certain fungal diseases. The control plants had a stem diameter of 2.63 mm, which significantly improved with the treatment compounds. Barley stem wall thickness increased significantly with both 150 and 300 mg.L-1 levels of calcium chloride, combined with all three levels of sodium silicate spraying. These factors play a role in determining the ultimate photosynthetic destination, as well as the efficiency and economic production of the target seed cultivar or crop.The results indicated a significant increase in grain yield when simultaneously applying 10 mg.kg-1 silicon with 6 mM calcium chloride, showing a 65% improvement compared to the control. Treatment with three potassium sulfate variations, combined with either 6 or 12 mM calcium chloride, or 12 mM calcium chloride alone, enhanced the flexural strength of the stem by 75%, 60%, and 62%, respectively. Among the treatment compounds studied, the shear strength of barley stems ranged from 2.63 MPa to 5.43 MPa. Plants treated with sodium silicate at concentrations of both 150 and 30 ml.L-1, in conjunction with 6 mM calcium chloride foliar application, exhibited higher shear strength compared to other treatments.ConclusionThis study demonstrated the tripartite effect of the treatments. The treatment composition derived from a surface area of 300 ml.L-1 of sodium, combined with 6 and 12 mM calcium chloride without potassium sulfate, had the greatest impact on flexural strength and stem diameter

    Trajectory of change in body mass index in Parkinson’s disease

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    IntroductionGastrointestinal (GI) symptoms are some of the most common non-motor symptoms in Parkinson's. Weight is a nutritional metric and can be affected by dysfunction of the gastrointestinal (GI) tract. This study aims to explore the change in trajectory of body mass index (BMI) in individuals with Parkinson's over the course of the disease including the prodromal and post-diagnostic periods.MethodsThis was a retrospective longitudinal study of data from participants from the PRIME Parkinson UK cross-sectional study. Participants were included if they had had one or more weights and height recorded in the primary care electronic health record.Results287 patients were initially included but only 234 could be included in the analysis of BMI trajectory. Using a piecewise linear mixed model, we determined that there was a ‘change point’ in BMI trajectory. This occurred on average 3.73 years after diagnosis, when the mean BMI was 26.4 kg/m2. Prior to this change point, the estimated mean rate of change in BMI was −0.09 kg/m2 (95 % credible interval −0.20,0.00 kg/m2) per year. However, after the change point, we observed a more accelerated decline in BMI, with an estimated mean rate of change of −0.34 kg/m2 (95 % credible interval −0.70,-0.07 kg/m2) per year.ConclusionThere was a modest weight loss trajectory in the pre-diagnostic period consistent with clinically stable weight. However, after several years, post-diagnosis BMI loss became more marked. In clinical practice interventions could be targeted at this time point to optimize and maintain nutritional intake

    Risk assessment of sari fatemeh zahra hospital using failure mode effect analysis, individualized rapid assessment tool, and preliminary hazard analysis

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    Abstract Background and purpose: Identification of risk in hospital waste management have a major role in reducing the cost of surplus and preventing the spread of diseases. In this quantitative analysis, we aimed at determining waste components, evaluating hospital waste management, and prioritizing the risks in Sari Fatemeh Zahra Hospital. Materials and methods: We performed a descriptive-cross-sectional study in 2015. Tchobanoglous method was used for quantitative-physical analysis of the waste. The individualized rapid assessment tool was applied to evaluate waste management. Preliminary Hazard Analysis and failure mode and effect analysis models were used to identify and prioritize the risks. Results: Total waste production, general waste, infectious wastes, and sharp objects were 1011.54, 600.45, 384.94, and 26.15 kg/day, respectively. Plastics, organic materials, and textiles constituted the highest amount of waste products. According to the individualized rapid assessment tool, the score obtained by the hospital was 82.15% indicating an excellent waste management. In preliminary hazard analysis, failure mode, and effect analysis models, 23 errors were observed, of which 9 had a priority number greater than 100. Conclusion: The models studied showed that mixing the sharp waste material with other garbage, disposal of non-infectious and semi-household waste in infectious bins and vice versa are of high risk and need corrective measures. Keywords: hospital waste management,quantitative analysis, risk assessment,preliminary hazard analysis, Hazard Analysis and Failure mode

    Porcospino Flex: a bio-inspired single-track robot with a 3D-printed, flexible, compliant vertebral column

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    This paper is focused on the design and development of the Porcospino Flex, a single-track robot inspired by nature and featuring a meta-material structure. In the earlier version of the Porcospino, the main body was composed of a chain of vertebrae and two end sections linked by flexible joints, but the excessive use of materials in 3D printing and the resulting weight of the robot posed challenges, ultimately leading to a decrease in its overall efficiency and performance. The Porcospino Flex is manufactured through the fused deposition modeling process using acrylonitrile butadiene styrene and thermoplastic polyurethane, featuring a singular meta-material structure vertebral column. The adoption of a lattice structure in the main body of the Porcospino Flex leads to a substantial increase in performance, reducing its weight from 4200 g to 3600 g. Furthermore, the decrease in weight leads to a reduction in material usage and waste, making a substantial contribution to the sustainability of the robot. The discussion focuses on the testing results of the Porcospino Flex prototype, highlighting the enhancements observed compared to its prior version

    TVOCs and BTEX concentrations in the air of south pars special economic energy zone

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    cold season were higher than those in warm season. High concentrations of Benzene in cold and warm seasons were used to identify areas of high exposure risk.survey TVOCs and BTEX in the air of South Pars Special Economic Energy Zone in 2014. Materials and methods: In a cross-sectional study sampling and analysis was done by NIOSH 1501 method. The study was carried out in 336 activated carbon tubes and personal sampling pump in 6 sampling stations during one year. The compounds were extracted by solvent carbon disulfide and analyzed using Gas Chromatography- Flame Ionization Detector (GC-FID). Data analysis was performed in SPSS Ver.18 applying Kruskal-Wallis, Fligner test and ANOVA. Results: The mean concentrations of TVOCs and TBTEX were 229.34 and 31.23 µg/m3 in cold season and 212.19 and 29.89 µg/m3 in warm season, respectively. The mean concentrations of Benzene in all stations were 11.72 µg/m3 which were higher than the threshold levels recommended by Iranian Clean Air Act and US Environmental Protection Agency (USEPA). The ANOVA results showed a significant difference between the concentration of pollutants and hour, month and sampling stations (P<0.05), but no significant difference was found between the concentration of pollutants and seasons (P>0.05). Conclusion: The concentrations of measured pollutants in cold season were higher than those in warm season. High concentrations of Benzene in cold and warm seasons were used to identify areas of high exposure risk. © 2016, AMazandaran University of Medical Sciences. All rights reserved

    Motor complications in Parkinson’s disease:results from 3,343 patients followed for up to 12 years

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    Background: Motor complications are well recognised in Parkinson’s disease (PD), but their reported prevalence varies and functional impact has not been well studied. Objectives: To quantify the presence, severity, impact and associated factors for motor complications in PD.Methods: Analysis of 3 large prospective cohort studies of recent-onset PD patients followed for up to 12 years. The MDS-UPDRS part 4 assessed motor complications and multivariable logistic regression tested for associations. Genetic risk score (GRS) for Parkinson’s was calculated from 79 single nucleotide polymorphisms. Results: 3,343 cases were included (64.7% male). Off periods affected 35.0% (95% CI 33.0, 37.0) at 4-6 years and 59.0% (55.6, 62.3) at 8-10 years. Dyskinesia affected 18.5% (95% CI 16.9, 20.2) at 4-6 years and 42.1% (38.7, 45.5) at 8-10 years. Dystonia affected 13.4% (12.1, 14.9) at 4-6 years and 22.8% (20.1, 25.9) at 8-10 years. Off periods consistently caused greater functional impact than dyskinesia. Motor complications were more common among those with higher drug doses, younger age at diagnosis, female gender, and greater dopaminergic responsiveness (in challenge tests), with associations emerging 2 to 4 years post-diagnosis. Higher Parkinson’s GRS was associated with early dyskinesia (0.026 ≤ P ≤ 0.050 from 2 to 6 years).Conclusions: Off periods are more common and cause greater functional impairment than dyskinesia. We confirm previously reported associations between motor 4 complications with several demographic and medication factors. Greater dopaminergic responsiveness and a higher genetic risk score are two novel and significant independent risk factors for the development of motor complications
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