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The effect of organosolv pretreatment on the structure of rice straw was analyzed under different treatment severities and solvent concentrations. At higher severities, on account of a greater fragmentation of less crystalline parts, including amorphous cellulose, hemicellulose, and lignin, the severer the pretreatment was, the higher the crystallinity index became; however, changes in the index was less tangible with a severity factor lower than 3.3. At the low to mild pretreatment temperatures (120 °C and 150 °C), higher ethanol concentrations led to the lower crystallinity index. Despite an increasing trend of crystallinity index at harsh conditions, SEM images indicated the formation of spherical droplets and pores on the treated rice straw, which is symptomatic of improved hydrolysis yields. A more detailed scrutiny of the flux patterns for the anaerobic metabolism of E. aerogenes revealed that the increase in both simple (glucose from 3 to 60 g l−1) and more complex (rice straw from 3.33 to 33.33 g l−1) substrate concentrations resulted in a lower hydrogen yield (54% and 77% reductions). Nonetheless, techno-economic assessments should be conducted to determine the optimum concentration. A preliminary economic evaluation of a simulated biorefinery showed due to the larger vessels and equipment, when the rice straw concentration in hydrolysis step decreased from 50 to 3.33 g l−1, the fixed capital investment sharply ascended by approximately 980% and, in contrast, the unit production cost decreased by 78%.

This study aims to construct a quantitative framework to assess biological production of hydrogen from agricultural residues in a country or region. The presented model is able to determine proper crops for biohydrogen production, its possible applications and use as well as environmental aspects. A multiplicative decomposition method was designed to forecast future production and Monte Carlo simulation was employed in the model to evaluate the risk of estimations. From 2013 to 2050, the hydrogen production capacity could increase from 53.59 to 164.41 kilotonnes (kt) in Iran. The highest contribution to biohydrogen production (52.1% in 2013 and 73.3% in 2050) belongs to cereal crops including wheat, barley, rice and corn and the share of horticultural products including apples, grapes and dates is the lowest (2.7% in 2013 and 2.2% in 2050). For possible variations in the quantity of collectable residue and biohydrogen yield, the production may change in the range of 40.16% and 209.48% of the base value in 2013 and 41.64% and 233.18% of that in 2050. Ammonia production as nitrogen fertilizer and the area could be cultivated by that for each crop were calculated. The amount of natural gas saving and reduction in greenhouse gas (GHG) emissions using biohydrogen were discussed. Development of hydrogen fuel cell vehicles and their impacts on the environment and consequent social costs as well as the quantity of gasoline would be saved were estimated by 2050.

Introduction: Evidence suggests that parents of children with mental or physical problems are more likely to have encountered numerous problems. Objective: The presented study was conducted with aim to determine the relation between marital satisfaction and parenting stress of mothers with efficacy in students with visual impairment. Method: this plan carried out in the area of descriptive studies in the form of causal-comparative study. The target formed the population included all male students with visual impairment living in Tehran and Karaj. For this purpose sixty (N =60) Students (age range 22-12, with average age: 18.2) were selected by available sampling method .Data collection was used on survey methods to assess index of parenting stress, marital satisfaction and self-efficacy questionnaire work by Schafer (response rate = 93%), Enrich (response rate = 90%) and general self-efficacy (response rate = 89%). Data collected were used with the help of Pearson correlation test, F-test and regression analysis. As well as qualitative data were analyzed obtained from the assessment coding demographic and qualitative data analysis tool Atlas.ti-5.2. Results: Data analysis showed that amount of stress between parenting stress and marital satisfaction with self-efficacy of children is significant. In this regard, parenting stress of mothers was determined by three variance levels of academic self-efficacy (r=-0.35), Social (r=-0.27) and emotional (r=-0.28). The results showed that women share of parenting stress in mothers in define of self-efficacy students was higher than the share of marital satisfaction. Conclusion: As the research literature shows, the results reflect the tension between the components of marital satisfaction; styles of parenting and students’ self-efficacy, the findings also offer preventive implications that could be important in the area of applications.

Introduction: Birth and presence of children with vision problems in every household could be considered a challenging event which will follow with stress, frustration and hopelessness. Objective: This study aimed to determine the relation between parenting stress with student’s self-efficacy who has visual impairment. Method: This study was conducted as a causal-comparative design in the form of a multi-site in the descriptive study field. The target formed the population included all male students with visual impairment living in Tehran and Karaj. For this purpose sixty (N =60) students (age range 22-12 with average age: 18.2) were selected by available sampling method. Data collection was based on survey methods to assess parenting stress in the index of Schiffer work questionnaires (response rate = 91%) was used. The collected data were analyzed using Pearson correlation test and F-test. As well as qualitative data were analyzed obtained from the assessment coding demographic and qualitative data analysis tool Atlas.ti-5.2. Results: Data analysis showed that between parenting stress of mothers There is a significant relationship with three levels of academic self-efficacy (r=-0.35), social (r=-0.27) and emotional (r=-0.28) .Conclusion: in line of management background, the results of this study indicate that there is a linear relationship between stress of parenting and efficacy in children, these findings could be promising outlook for future interventions.