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Na2CO3/γ-Al2O3 is one of the most promising sorbents to capture CO2 from industrial flue gas streams due to its high efficiency in low-temperature and low cost. The textural properties of the γ-Al2O3 support, such as specific surface area and pore volume play key roles in performance of the sorbent. Therefore, the aim of this study was to improve the sorbent performance, using several γ-Al2O3 supports, prepared through a modified sol-gel process in the presence of polyethylene glycol (PEG). N2 adsorption-desorption analysis showed that the pore volume and specific surface area of the sample with the PEG/Al(OPri)3 mole ratio of 0.05 were, respectively, about 340 % and 38 % higher than the sample synthesized in the absence of PEG. In addition, improving the specific surface area and pore volume of γ-Al2O3 enhanced the total CO2 capture capacity of a Na2CO3/γ-Al2O3 sorbent by 34 %. Moreover, the effect of Na2CO3 loading on the best γ-Al2O3 sample was investigated, and the optimum loading of Na2CO3 and the corresponding total CO2 capture capacity were observed to be 50 wt.% and 131.6 mg CO2/gsorbent, respectively. Finally, the regeneration conditions of the sodium-based sorbent were determined using chemical kinetic study and temperature programmed desorption (TPD) analysis.

As one of the most common work-related musculoskeletal disorders and postural deviations, forward head posture (FHP), is considered to lead to muscle imbalance.The aim of this study is to investigate the bilateral cross-sectional area (CSA) of the deep neck flexor muscles at rest and during five stages of the craniocervical flexion (CCF) test in individuals with FHP and the controls with normal head posture.Eighteen students with FHP and 18 controls with normal head posture, all females aged 18-35 years, participated in this study. Participants were categorized into two groups based on their craniovertebral angle. The CSA of the deep neck flexors was measured using ultrasonography while participants lay supine on the table with a pressure biofeedback unit placed under their necks in order to let the examiner measure the CSA of the muscles during rest and five stages of the CCF test including 22, 24, 26, 28, and 30 mmHg of the pressure biofeedback unit.A significant effect of contraction level was observed in both groups, indicating significant increases of the CSA of the deep neck flexors during contraction (F = 64.37, P 0.001). No significant difference was evident for the CSA of the deep neck flexors between the groups, although the increase in the CSA of the deep neck flexors was up to 28 mmHg in the normal head posture group compared to 26 mmHg in the FHP group.The results of the present study showed no significant difference between the performance of the deep neck flexors during the CCF test in FHP and normal head posture individuals, which challenge the common belief of the deep neck flexors weakness in individuals sustaining FHP.

In this research, the effects of air swirling on the emission and combustion characteristics of a cylindrical furnace fueled with various diesel-biodiesel-n-butanol and diesel-biodiesel-methanol blends were studied. The tests conducted on a burner with a radial air swirler and different vane angles (15°, 25°, 35°, 45°, 60°, and 90°) that was mounted to the combustion chamber. The results showed that the air swirler with vane angles of 35° and 60° can improve the CO and HC emission. Also, the CO2 and NOx emissions improved at the angles of 45° and 60°. The results indicated that the use of n-butanol and methanol as the mixture with diesel-biodiesel blends can improve the CO and HC emissions compared to neat diesel combustion. However, a five percent increase in methanol and butanol amount resulted in an increase (around 18%) in these pollutants. On the other hand, an increase in the percentage of alcohol in fuel mixture can reduce CO2 and NOx emissions up to 12%. According to the results, the mean temperature of combustion gas decreased about 2% in some points with the addition of n-butanol and methanol in the fuel mixture due to the small cetane number and lower heating value of these alcohols compared to diesel and biodiesel. The results indicated that air swirler with the vane angle of 60° had a better condition for the reduction of pollutants among other angles.

Amiri, Jafarian Amiri and Isaacs proved that the cyclic group has maximum sum of element orders on all groups of the same order. In this article we characterize finite groups which have maximum sum of element orders among all noncyclic groups of the same order. This result confirms the conjecture posed in Jafarian Amiri (2013) [2].

This paper introduces an approach to one of the most important problems in electrical power system called the Unit Commitment (UC). The proposed method PUC-MP which stands for the primary unit commitment-modification process, addresses this problem firstly by using a simple and new priority for operating the generating units in each hour, and then, using a modification process which enhances the solution quality with lower cost. The PUC-MP takes advantage of both deterministic and stochastic algorithms in its structure to solve the discrete-variable part of the UC problem for choosing a suitable combination of units in each hour, and also, continuous-variable part of it which is dispatching the operating units' output power to the power network load economically. The latter part which is called economic dispatch (ED) has been solved using an intelligent algorithm which in turn has been customized by two new ideas to increase its efficiency. Simulation results show that this new approach even without using its modification process can be considered as an effective approach which surpasses some other popular and recently reported methods in producing near-optimal and robust solutions.

Summary In this study, the reliability of the longus colli muscle (LCM) size was assessed in a relaxed state by a real time ultrasonography (US) device in a group of healthy subjects and a group of patients with chronic neck pain. Fifteen healthy subjects (19–41years old) and 10 patients with chronic neck pain (27–44years old) were recruited for the purpose of this study. LCM size was measured at the level of thyroid cartilage. Two images were taken on the same day with an hour interval to assess the within day reliability and the third image was taken 1week later to determine between days reliability. Cross sectional area (CSA), anterior posterior dimension (APD), and lateral dimension (LD) were measured each time. The shape ratio was calculated as LD/APD. Intraclass correlation coefficients (ICC) and standard error of measurement (SEM) were computed for data analysis. The ICC of left and right CSA for within day and between days reliability in healthy subjects were (0.90, 0.93) and (0.85, 0.82), respectively. The ICC of left and right CSA for within day and between days reliability in patients with neck pain were (0.86, 0.82) and (0.76, 0.81), respectively. The results indicated that US could be used as a reliable tool to measure the LCM dimensions in healthy subjects and patients with chronic neck pain.

In this work, M 4 cubic equation of state (EOS) (proposed by Mohsen-Nia et al., 2003 ) is applied to calculate the saturated properties of refrigerants. A wide range of different types of refrigerants (CFCs, HCFCs, HFCS, etc.) is examined by calculating their saturated pressures, saturated liquid and vapor molar volumes. The comparison between the VLE calculation results and the experimental data, shows that the agreement of this EOS is better than two frequently-used (SRK and PR) EOSs for 42 refrigerants and some of their mixtures.

Objective This article presents a review of the literature concerning size measurement of cervical muscles using real-time ultrasound imaging (RUSI) in patients with neck pain and in healthy populations. Methods A literature search from 1996 to December 2009 making use of Science Direct and PubMed databases was conducted. Medical Subject Headings and other terms were as follows: ultrasonography , cervical , muscle , neck , size , pain , validity , reliability , neck pain , and healthy subjects . We included studies using RUSI for assessing cervical paraspinal muscles both in healthy subjects and in patients with neck pain. We assessed muscles investigated and the reliability and validity of the method used. Results The literature search yielded 16 studies. Twelve (75%) studies assessed the posterior muscles, whereas in the remaining 4 (25%), the anterior muscles were studied. Three studies quantified the size of the muscles during contraction; 3 assessed the relationship between cross-sectional area, linear dimensions, and anthropometric variables; 1 evaluated the training-induced changes in muscle size; 1 assessed the differences in muscle shape and cross-sectional area of cervical multifidus between patients with chronic neck pain and controls; 8 studies looked at the reliability of using RUSI in patients with neck pain or healthy subjects; and 3 studies evaluated the validity of RUSI compared with magnetic resonance imaging. Conclusions This literature review has shown that there are not sufficient studies for assessing neck muscles with RUSI. It seems that using constant landmarks, knowledge of anatomy and function of target muscle, and a proper definition of muscle borders can help to take a clear image. Standardized position of the subject, correct placement of the transducer, and using multiple RUSI for statistical analyses may improve results.

The current study was conducted to explore the relationship between suicidal ideas, depression, anxiety, resiliency, daily stresses and mental health among university students. 265 students of Tehran University were studied. They were asked to answer the Beck's depression and anxiety, suicidal ideation, mental health, daily stresses and resiliency questioners. Pearson correlation coefficient and stepwise regression analyses were used for the data analysis. Suicidal ideations had a significant and negative relationship with resiliency. Anxiety, depression, mental health and daily stresses had a positive relationship with suicidal ideations. Regression analysis revealed that depression had the most contribution in predicting suicidal ideations while anxiety, mental health, Resiliency, and daily stresses were the next contributing factors, respectively. These variables could predict 21 percent of suicidal ideations altogether. Psychological problems and mental health issues and other factors such as resiliency and daily stresses play an important role in suicidal ideations.

The present study aimed at the comparison of the prevalence of ADHD and also the components of the disorder (hyperactivity’attention deficit and impulsivity) among patients with substance use disorder and normal people. To achieve the goal‚ 85 patients were selected among clients referring to addiction treatment centers in Tehran city‚ and 85 normal subjects were selected using at-hand sampling. Data from the subjects were collected using the Adult Questionnaire – Childhood ADHD Symptoms Rating Scale (AQ- CASRS). Data were analyzed using T-test: Results indicated there existed a significant difference between patients with substance use disorder and normal people in terms of their total scores in ADHD and its components: patients with substance use disorder reported more problems and symptoms compared to normal people.