Ayyob Rastegar; Zahra Rezaee Gezal Abad; Ahmad Allahabadi; Abolfazl Rahmani Sani; RamezanAli Khamirchi
Volume 21, Issue 6 , January and February 2015, , Pages 1090-1102
Abstract
Background: Aniline is an important chemical compound which has wide applications in several industries such as dyestuffs, rubbers, pesticides and plastics. It is highly toxic and has injurious influences on human physical conditions and aquatic life. Therefore the purpose of this study is to investigate ...
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Background: Aniline is an important chemical compound which has wide applications in several industries such as dyestuffs, rubbers, pesticides and plastics. It is highly toxic and has injurious influences on human physical conditions and aquatic life. Therefore the purpose of this study is to investigate the effects of NH4Cl-induced activated carbon (NAC) and standard activated carbon (SAC) in aniline removal from aqueous solutions were investigated. Material & method: This study is of experimental–intervention type. An UV-Visible spectrophotometer (CECIL CE7400) used For determination of remaining aniline concentrations. The effect of various parameters like adsorbent dose, pH, contact time and initial aniline concentration were studied for optimization.
Results: The results showed that the prepared NAC had a higher absorption capacity than standard activated one. The maximum adsorption capacity of aniline onto SAC and NAC was 1666 and 1000 mg/g, respectively, and the rate removal was dependended to pH, contact time, aniline concentration and absorption type. Results of equilibrium experiments indicated that the adsorption process of aniline onto SAC and NAC follows Langmuir model (R 2> 0.99.47 and 0.99,776 ). Also, kinetics of adsorption process follows pseudo second-order model with correlation R2> 0.99.97 and 0.99,30 respectively for SAC and NAC.
Conclusion: These consequences show that the developed NAC was a more competent adsorbent than SAS for removal aniline in water.
Ramezanali Khamirchi; MohammadHasan Rakhshani; Ali Malihi; Hamid Mehri; Akbar Ahmadi Asour
Volume 21, Issue 5 , September and October 2014, , Pages 942-950
Abstract
Background and Purpose: Traditional baker’s occupation is a complex of long repetitive tasks and movements with high intensity which exposes the baker into musculoskeletal disorders. The aim of this study was a detailed analysis of risk factors leading to the incidence of musculoskeletal disorders ...
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Background and Purpose: Traditional baker’s occupation is a complex of long repetitive tasks and movements with high intensity which exposes the baker into musculoskeletal disorders. The aim of this study was a detailed analysis of risk factors leading to the incidence of musculoskeletal disorders in Sabzevar bakers.
Materials and Methods: This cross-sectional descriptive study was conducted on 70 traditional bakers in Sabzevar, Iran who were selected by simple random sampling. First, the prevalence of musculoskeletal disorders was determined using Nordic Musculoskeletal Questionnaire; then, Rapid Upper Lumbar assessment (RULA) was used for assessing postures to obtain final scores. Data were analyzed using R software (version R2.15.2).
Results: Based on the findings, the average age and work experience of bakers were 19.4 and 36.4 years respectively. The most symptomatic risk factors were related to shoulder (%56.8) and knees (50%). In assessing Rapid Upper Lumbar assessment (RULA), 33.34% of personnel (correction level 4) obtained 7, and 55% obtained 5 and 6 (with Corrective level 3). Non-parametric showed significant correlation between the musculoskeletal disorders and age (p = 0.02) and work experience (p = 0.03) (confidence level 95%). In other words, bakers with older age and more work experience suffered from more disorders
Conclusion: Based on the results, a significant percentage of traditional bakers work in an ergonomically unsafe environment (%88.3), and the frequency of musculoskeletal disorders is high in this population; this requires urgent ergonomic and managerial action.
Akbar Ahmadi Asour; Mohammad Hossein Saghi; Ramezanali Khamirchi; Tahereh Vaziri; Ayyob Rastegar
Volume 20, Issue 2 , May and June 2013, , Pages 222-229
Abstract
Introduction: Unnecessary use of chemical manure in order to increase the crop production, particularly in the agricultural sector, causes environmental damages and disorder in terms of soil fertility. In the manure preparation method through the biogas, organic manure of high quality can be produced ...
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Introduction: Unnecessary use of chemical manure in order to increase the crop production, particularly in the agricultural sector, causes environmental damages and disorder in terms of soil fertility. In the manure preparation method through the biogas, organic manure of high quality can be produced in addition to obtaining gas. The purpose of this study is to examine the physical as well as chemical properties of the manure produced by the combined wastes of livestock and poultry using biogas system.
Research method: In order to put the pilot project into operation, livestock and poultry wastes were primarily collected and were added to the planned pilot in a proportional ratio of 1:2. After about two months, the produced gas was measured and the parameters of the manure were analyzed according to the pilot sample and subsequently, they were compared with the existing standards. Using EXCEL, the gathered data were analyzed.
Results: PH rate obtained from the manure was estimated to be 7.2. Reportedly, the electrical conductivity of the sample was equal to 29.53 ml. Siemens/cm. and the humidity was 5%. The organic compounds in the sample were 8.19% and ash was 8.58%. Furthermore, the rate of the organic carbon for the sample was 40% and the size of the uniformed particles was of the highest mesh, i.e. 50. The manure obtained has a phosphorous concentration of 1 mg/l and the sodium concentration obtained were 94 mg/l and potassium 74 mg/l.
Discussion and conclusion: Findings indicate that the rate of organic materials, phosphorus, ash and organic carbon are consistent with the standards set by WHO. With regard to low cost, availability, being danger-free and enriched as well as the simultaneous use of the gas produced, the manure obtained through the biogas can be considered a suitable kind of manure for agriculture.