1,201 research outputs found
Experimental Study of Adsorption on Activated Carbon for CO<sub>2</sub> Capture
The adsorption of carbon dioxide (CO2) on activated carbon (AC) prepared from olive trees has been investigated by using a fixed bed adsorption apparatus. The adsorption equilibrium and breakthrough curves were determined at different temperatures 30, 50, 70, and 90°C in order to investigate both kinetic and thermodynamic parameters. Maximum CO2 sorption capacity on AC ranged from 109.5 to 35.46 and from 129.65 to 35.55 mg CO2/g of AC for initial concentrations 10 and 13.725% vol., respectively. Different isotherm models are applied to mathematically model the CO2 adsorption, and on the basis of the estimated adsorption capacity by model and determination coefficient (r2), the Langmuir model provides a perfect fit to the experimental data owing to closeness of the r2 to unity. From the correlation coefficient, it is found that the pseudo-second-order model is well-fitted with the experimental data. In addition, it indicates that CO2 adsorption is a physical adsorption process and demonstrates a behavior of an exothermic reaction, which is consistent with the thermodynamic analysis. The results obtained in this study conclude that AC prepared from olive trees can be considered as adequate for designing a fixed bed cycle to separate carbon dioxide from flue gases and serve as a benchmark while searching for inexpensive and superior activated carbon production in future studies
Editorial
Editorial - Inaugural issue - Volume 1 Number 1International Journal of Biotechnolgy for Wellness Industrie
Clinical and radiological outcomes of arthroscopic subcoracoid decompression for idiopathic coracoid impingement, a stepped approach
Background: Idiopathic subcoracoid impingement is considered now as a well-established cause of anterior shoulder pain. There are multiple techniques reported for management of subcoracoid impingement. Open decompression and reattachment of conjoint tendon as well as arthroscopic resection of coracoid tip. The aim of this study was to evaluate the results of arthroscopic stepwise approach for management of idiopathic coracoid impingment.Methods: This prospective therapeutic case series study included 26 consecutive patients suffering from anterior shoulder pain and were diagnosed as subcoracoid impingement. All cases were evaluated preoperatively and followed up for 12 months after surgery both clinically and radiologically. Arthroscopic subcoracoid decompression, coracoplasty and arthroscopic repair of partial subscapularis tear if present were done for all cases.Results: The mean age at the time of surgery was 45.3±5.4years. At the final follow up, the mean VAS score improved significantly to 0.8±0.8points postoperatively (p<0.01). The mean Constant score improved significantly to 87.8±7.8 at the final follow-up (p<0.001). The mean UCLA score improved significantly to 32.1±2.4 at the end of follow-up (P<0.001)Conclusions: Coracoid impingement should be in mind when evaluating any patient with anterior shoulder pain. The arthroscopic management in form of bone, bursal and tendon procedures (triple attack) is a good treatment to relieve clinical symptoms with excellent patient reported outcomes.
Investigating the Effect of Sulfate Attack on Compressive Strength of Recycled Aggregate Concrete
This research aimed at studying the effect of sulfate attack on the compressive concrete strength with various percentages of recycled aggregate replacements (0%, 30%, 60% and 100%). Water cement ratio (0.42) are used, MgSO4 solution was used with two concentration (6% and 9 %) to represent the effect of sulfate attack on the concrete compressive strength. The experimental tests focused on physical properties of recycled aggregate; density, unit weight, sieve analysis, Los Angles test and specific gravity. Tests have also been performed on 108 concrete cubes samples at 7 days, 14 days and 28 days for compressive strength. The results of  compressive strength at 28 days using (0%, 30%, 60% and 100%) recycled aggregate are (330, 280, 266 and 244) Kg/cm2 respectively, with reduction in compressive strength was (15.2%, 19.4% and 26%)  for replacement ratio (30%, 60% and 100%) respectively. MgSO4 solution has an effect on compressive strength after 90 days of immersion in 6% and 9% concentrated of MgSO4 solution. The results of this study show that the reduction in compressive strength using recycled aggregate is more sensitive against the sulfate attack compared with natural aggregate
Application of Recurrent Neural Networks for Drought Projections in California
We use recurrent neural networks (RNNs) to investigate the complex interactions between the long-term trend in dryness and a projected, short but intense, period of wetness due to the 2015-2016 El Niño. Although it was forecasted that this El Niño season would bring significant rainfall to the region, our long-term projections of the Palmer Z Index (PZI) showed a continuing drought trend, contrasting with the 1998-1999 El Niño event. RNN training considered PZI data during 1896-2006 that was validated against the 2006-2015 period to evaluate the potential of extreme precipitation forecast. We achieved a statistically significant correlation of 0.610 between forecasted and observed PZI on the validation set for a lead time of 1 month. This gives strong confidence to the forecasted precipitation indicator. The 2015-2016 El Niño season proved to be relatively weak as compared with the 1997-1998, with a peak PZI anomaly of 0.242 standard deviations below historical averages, continuing drought conditions
Melittin Exerts Beneficial Effects on Paraquat-Induced Lung Injuries in Mice by Modifying Oxidative Stress and Apoptosis
Melittin (MEL) is a 26-amino acid peptide with numerous biological activities. Paraquat (PQ) is one of the most widely used herbicides, although it is extremely toxic to humans. To date, PQ poisoning has no effective treatment, and therefore the current study aimed to assess for the first time the possible effects of MEL on PQ-induced lung injuries in mice. Mice received a single intraperitoneal (IP) injection of PQ (30 mg/kg), followed by IP treatment with MEL (0.1 and 0.5 mg/kg) twice per week for four consecutive weeks. Histological alterations, oxidative stress, and apoptosis in the lungs were studied. Hematoxylin and eosin (H&E) staining indicated that MEL markedly reduced lung injuries induced by PQ. Furthermore, treatment with MEL increased superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activity, and decreased malonaldehyde (MDA) and nitric oxide (NO) levels in lung tissue homogenates. Moreover, immunohistochemical staining showed that B-cell lymphoma-2 (Bcl-2) and survivin expressions were upregulated after MEL treatment, while Ki-67 expression was downregulated. The high dose of MEL was more effective than the low dose in all experiments. In summary, MEL efficiently reduced PQ-induced lung injuries in mice. Specific pharmacological examinations are required to determine the effectiveness of MEL in cases of human PQ poisoning
The role of magnetic resonance imaging and magnetic resonance sialography in the evaluation of salivary sialolithiasis : radiologic-endoscopic correlation
Purpose: To evaluate the role of magnetic resonance imaging (MRI) and MR sialography in salivary gland calculi in correlation with sialendoscopy. Material and methods: In this prospective study, pre-therapeutic MRI was performed for patients with clinically suspected sialolithiasis. In addition, sialendoscopy with or without surgery was performed. The detectability, number, size, and location of calculi (distance of obstruction from the ostium and masseter line) and the condition of the main duct at MRI were reported. Agreement between the 2 readers was confirmed for all MRI findings. Data regarding the detectability, number, and size of calculi were correlated with endoscopy. Results: There was excellent agreement between the 2 readers regarding the detection and number of calculi at MR sialography (κ = 1, p < 0.001). As regards MRI measurements, excellent interclass correlation was found between the 2 readers regarding size of calculi, distance of calculi from the ostium, and distance from the masseter line (κ = 0.98, 0.98, 0.97, respectively; p < 0.001). In correlation with sialendoscopy, MRI was false negative in 1 patient,
and it missed 1 calculus in 3 patients with multiple calculi. There was no statistically significant difference between the size of calculi detected by MRI and true size of calculi retrieved by sialendoscopy. Conclusion: MR sialography is an accurate modality for diagnosis of the presence, size, and location of sialolithiasis
and offers accurate ductal mapping for sialendoscopists
STR-990: SUSTAINABLE GROUTED HELICAL PILES: MATERIALS AND PERFORMANCE
Cementitious materials are widely used as a construction material all over the world. However, cement industry has high environmental impact such as the release of CO2 and the consumption of natural resources for its manufacturing energy. Therefore, reducing cement consumption is vital to achieve sustainable green construction practices. In this study, the effects of using treated oil sand waste (TOSW) as a partial replacement of cement in grouted helical pile applications were investigated. Fresh and hardened properties of the green grout incorporating different percentages of TOSW were evaluated. In addition, a model scale grouted helical pile with the green grout was tested to characterize its performance. The experimental results show that the properties of TOSW grout mixes were comparable to conventional grout and satisfy the strength and construction requirements of grouted piles. Moreover, tested grouted helical pile using the developed mixture exhibited similar geotechnical performance as those installed using conventional grout mix. Hence, TOSW can be implemented in grouted helical pile applications, which would assist in achieving sustainable construction
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