TitleConverting Polystyrene and Corn Waste into Activated Carbon with High Surface Area
Paper ID9iHvr
KeywordsActivated Carbon, Co-Pyrolysis, Corn stover, Polystyrene plastic, Synergistic Effects.
Abstract
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The significant challenges of plastic waste management and agricultural by-product
treatment demand innovative and sustainable solutions. Polystyrene (PS) is a widely used
synthetic polymer; however, without effective post-use treatment, it can cause significant
adverse impacts on both human health and the environment. In recent years, co-pyrolysis
technology has emerged as a promising thermochemical approach for converting such
materials into value-added products. This work investigates the co-pyrolysis of both PS
and CS to produce biochar (BC), followed by chemical activation using 5 M KOH to obtain
activated carbon (AC) with high surface area. We found that the optimal conditions for copyrolysis were identified at a PS:CS mass ratio of 1:2, a temperature of 500 °C, and a
residence time of 1.5 h. The BC obtained under these conditions exhibited a surface area
of 58.74 m² g⁻¹. Subsequent the activation process with KOH at a BC: KOH mass ratio of
1:3, a temperature of 750 °C, and a duration of 3h have synthesized the achieved AC with
an excellent surface area of 914.83 m² g⁻¹.The results of work demonstrate the promising
of combining co-pyrolysis with chemical activation as a sustainable strategy for waste
valorization that promise for wider applications in environmental energy storage, and other
advanced technological fields.

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TitleAnalysis of wind potential energy - in three selected locations - south-east Nigeria
Paper IDPHj53/NA
KeywordsMean wind speed, Wind power density, South-east Nigeria, Electricity, Water pumping
Abstract
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In this study, the wind speed characteristics and energy potential in three selected locations in the south-eastern part of Nigeria were investigated using wind speed data that span between 24 and 37 years and measured at a height of 10 m. It was shown that the annual mean wind speed at a height of 10 m for Enugu, Owerri and Onitsha are 5.42, 3.36 and 3.59 m/s, respectively, while the annual mean power densities are 96.98, 23.23 and 28.34 W/m2, respectively. It was further shown that the mean annual value of the most probable wind speed are 5.47, 3.72 and 3.50 m/s for Enugu, Owerri and Onitsha, respectively, while the respective annual value of the wind speed carrying maximum energy are 6.48, 4.33 and 3.90 m/s. The performance of selected commercial wind turbine models (with rated power between 50 and 1,000 kW) designed for electricity generation and a windmill (rated power, 0.36 kW) for water pumping located in these sites was examined. The annual energy output and capacity factor for these turbines, as well as the water produced by the windmill, were determined. The minimum required design parameters for a wind turbine to be a viable option for electricity generation in each location are also suggested

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TitleUtilization of moving bed biofilm reactor for industrial wastewater treatment containing Ethylene Glycol
Paper ID0MSjE
KeywordsNervous System (CNS),ozonation,atrazine
Abstract
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Many environmental problems such as: negative effects on aquatic life, destruction of aquatic ecosystems, soil pollution, reducing the oxygen level in the water absorption through skin contact, brain damages, damage to the Central Nervous System (CNS) and joints, eye damage, toxicity, etc., have been reported related with EG. In this study, ozone as an advanced oxidation method was used for the treatment of EG containing wastewaters. For this purpose, the impact of contact time and pH variations on EG removal by ozonation at two level including low and high concentration (low= 5, 10, 20, 50, 100 and high=500, 750, 1000, 1500 mg/L) were examined. An EG removal kinetic analysis was determined based on removal rates via several ozonation times. At concentrations of 10, 20 and 50 mg/L after 180 minutes, removal of EG were achieved 93.31, 89.96, and 85.01 % respectively. Increasing pH has a direct impact on system efficiency and maximum efficiency corresponds to a concentration of 1500 mg/L 20.26 % was observed. Very good correlation coefficients at this kinetic study at all concentrations, investigated that EG removal will follow the first-order kinetics. Increasing and decreasing pH has a dramatic effect on the efficiency of the system, so that the efficiency increases significantly at alkaline pH. According to the results ozone system can be an excellent option for EG containing wastewater treatment.

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TitleAssociation between knee pain and low back pain
Paper ID2JxE8
KeywordsKnee pain, Low back pain, Lumbar posture
Abstract
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Introduction: Knee pain and low back pain are major public health issues and important causes of physical impairment among the elderly populations of most developed countries. When knee pain and low back pain and/or dysfunction occur together a complex situation that is capable of causing more disability occurs. Although the prevalence of knee pain and low back pain is quiet high little information is available on their association together. Physicians need to be able to recognize when, how and how much these conditions present together and know how to diagnose and treat them. Because a limited amount of research exists regarding the potential temporal relationships between knee pain and low back pain (LBP), the purpose of this study was evaluation of coincidence and correlation of knee pain with lumbar disorders. Methods: This descriptive-analytic and case-control study was conducted in patients referred with knee pain complaint to physical medicine and rehabilitation outpatient clinic. Ninety patients with main complaint of knee pain were selected as case group and 90 patient whose main complaint were other than knee pain and low back pain were included into control group. Coincidence of knee pain and lumbar disorders were assessed and compared in case and control groups. Results: On the whole, 38 patients (22.4%) were male and 132 (77.6%) were women. In the case group, 20 individuals (22.2%) were male and 70 patients (8/77%) were female. In the control group, 18 patients (22.5%) were male and 62 patients (77.5%) were female. Gender composition between two groups was not significant. The mean age of the study population were 46.9±8.9 with range of 25 to 61 years. The mean age in the case and control groups was 47±9.2 years (25-61) and 46.7±8.6 years (25-61), respectively. No statistically significant difference between the groups was noted. Eighty percent of patients of case group and 58.8% of control one had experienced LBP at some point (P=0.002). Life time prevalence for radicular LBP (P=0.02), chronic LBP (P=0.001), recurrent LBP (P=0.0001) of case group was higher than case group. Point prevalence of LBP was 57.7 % in case group and 28.8% in control one (P=0.0001). Range of motion (ROM) of lower limb and lumbar region, especially, for flexion and lateral bending in case group was less than control one. There was no significant difference in vertebral column posture between two groups. Trophedema of lumbar region was greater in case group than control one. Conclusion: Considering the high prevalence of low back pain, more lumbar trophedema and greater limitation of range of motion in lumbar and lower extremity joints in cases, the relationship between lumbar and knee pain disorders in patients should attract greater attention for assessments and managements of patients with knee pain. Further investigation would be helpful

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TitleThe effects of corporate board and CEO characteristics on firm value: Empirical evidence from Romanian listed companies
Paper IDJi8ST
Keywordsboard of directors, agency theory, stewardship theory, resource dependence theory, emerging markets, firm value
Abstract
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The aim of this research consist in providing the first empirical evidence toward the effects of corporate board and CEO characteristics on firm value for the case of Romanian listed companies. We considered the following characteristics as regards board of directors: board independence, board committees, board size, and board diversity. CEO characteristics comprise age, tenure, duality, state of residence, and gender. The empirical research was employed for a sample of companies listed on the Bucharest Stock Exchange over 2007-2011. In order to catch the effects of selected variables on firm value we estimated multivariate regression models for panel data. Consistent with prior literature we employed industry-adjusted Tobin’s Q ratio to measure firm value. There resulted a positive effect of independent non-executive directors on firm value, whereas for non-executive directors the relationship was not statistically validated. Given the reduced number of companies which established board committees we concluded the lack of theirs influence on firm value. We notice a negative relationship between board size and firm value although not robust in all econometric specifications. We also find that female representation on board should be at least twenty percent in order to show a positive effect on firm value. The results provide support for a lack of any statistically significant relationship between CEO duality, CEO age, CEO tenure, and industry-adjusted Tobin’s Q ratio. Besides, CEO gender and CEO state of residence exhibit a positive effect on firm value.

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TitleBrief review: Favism and Percutaneous Coronary Intervention with Drug-eluting Stents. The safety of Aspirin
Paper IDAiQdY
KeywordsG6PD deficiency, double antiplatelet treatment, coronary angioplasty
Abstract
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Favism represents the clinical manifestation of Glucose 6-phosphate dehydrogenase (G6PD) deficiency and induces acute hemolytic anemia after the ingestion of fava beans or the consumption of several drugs such as antimalarias, sulfonamides and aspirin. It is known that aspirin is the cornerstone of percutaneous coronary intervention (PCI) and patients who are contraindicated for aspirin intake because of hypersensitivity or active gastric bleeding pose a challenge for PCI. G6PD deficiency is another condition in which aspirin treatment is generally contraindicated. We present a literature review of patients with known G6PD deficiency that needed to undergo PCI using drug eluting stent (DES) and double antiplatelet treatment.

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TitleRenographic study of unilateral stenosis in the rabbit's left kidney
Paper IDXDq1u
KeywordsKidney, Rabbit, Renogram , Stenosis, 99mTc-DTPA
Abstract
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The aim of this study was to evaluate the induced changes in curve of activity against time (Renogram) in unilateral rabbit's left kidney stenosis. Renal scintigraphy is a diagnostic technique imaging to evaluate the kidney and its function in which the special radioactive substance is injected intravenously. Renal activity is evaluated by gama camera machine and a curve of activity against time is plotted by computer. Changes in the shape of the renogram can be helpful in diagnosing renal diseases. Early diagnosis of renal stenosis can lead to appropriate therapy and so cause reduces involvement side effects. In order to evaluate the renogram of the left kidney stenosis, ten nonpregnant Germen female rabbits were chosen and the semi left renal artery was occluded by ligation. Scintigraphy was under anesthetic condition with using 99m-DTPA radiodrug .The radioactive substance was injected rapidly through the marginal ear vein. Immediately after intravenous injection of radiodrug scintigraphic operations were done and computerized dynamic scans were gathered to plot the renogram curve. The ROIs can be drawn in scans and radioactive counting was easily measured. In our results, the renograms showed that the graph of renal stenosis had not reached the maximum level and the evacuation phase was delayed. The percentage of radioactive substance reaching both kidneys had decreased and in the stenotic kidney it decreased drastically. It shows the stenosis status in comparison to the normal kidney. Thus scintigraphy and renograms could be used noninvasively and accurately to diagnose unilateral stenosis in the rabbit kidney.

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TitleTraffic Based Random Deployment of Relay Nodes in Wireless Sensor Networks
Paper ID3j2kE
KeywordsBase Station (BS), Biased Energy Consumption Rate (BECR), Data Collection Round (DCR), Energy Depletion Intensity (EDI), Relay Node (RN), and Wireless Sensor Network (WSN).
Abstract
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Relay nodes are used in the transfer of the data packets to the base station (BS) via the sensor nodes (SN). The placement of RNs influences the lifetime and connectivity of a Wireless Sensor Network (WSN) system. A traffic aware random deployment technique for the relay nodes is proposed in this paper. The scalability and traffic of the WSN are analyzed. A traffic aware RN selection is performed for both single hop and multi hop communication cases. Traffic based random deployment methods of RN, namely, lifetime-oriented deployment, and hybrid deployment, solve the issue of a short WSN lifetime and insufficient energy utilization. The trade-off between the lifetime extension and connectivity of SN in a WSN is considered in the performance analysis. The proposed method provides an efficient approach for the placement of RNs in a heterogeneous WSN.

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TitleOptimization and Modelling of Chemical Oxygen Demand Removal by ANAMMOX Process Using Response Surface Methodology
Paper IDhnalb/NA
Keywordsoptimization and modelling, Nitrogen removal, Advance waste water treatment, Tertiary treatment, Biological waste water treatment
Abstract
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In this paper, a systematic model for chemical oxygen demand (COD) removal using the ANAMMOX process was provided based on an experimental design. At first, the experimental data was collected from a combined biological aerobic/anaerobic reactor. For modelling and optimization of COD removal, the main parameters were considered, such as COD loading, ammonium, pH, and temperature. From the models,the optimum conditions were determined as COD 97.5 mg/L, ammonium concentration equal to 28.75 mg-N/L, pH 7.72 and temperature 31.3oC. Finally, the analysis of the optimum conditions, performed by the response surface method, predicted COD removal efficiency of 81.07% at the optimum condition.

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