Showing 3 results for kariminia
Volume 4, Issue 1 (10-2013)
Abstract
The production of bioethanol from lignocellulosic biomass could be considered as an appropriate and economic option to remove environmental disasters and improve energy security. In fact, lignocellulosic material is mainly composed of cellulose, hemicellulose and lignin. Lignin works as the adhering prevents the bioconversion of cellulose into sugars and ultimately to ethanol. To address the problem, various chemical, physical, physicochemical and biological methods have been suggested. Enjoying convenient operating conditions, production of non-hazardous wastes, and having no harmful side effects, make the biological methods a potentially proper option. Unfortunately, the biological methods are slower and less efficient in comparison with the other processes. In the present study, an attempt is made to resolve this problem in an enzymatic degradation of lignin of a rice straw sample. Several peroxidase enzymes were produced by a white rot fungus, and their effects on lignin removal from the biomass samples were investigated in shaking flasks. Lignin concentration and enzymes' activity were measured by the acetyl bromide-soluble lignin spectrophotometric method and optical density method using special reagents, respectively. The results revealed that the enzymatic treatment could remove at least 30% of the lignin content of the lignocellulosic biomass. To achieve the maximum activity of the enzymes, The chemical composition of the culturing medium was optimized for the concentration of important metal ions including Cu2+, Mn2+ and Zn2+ through Box Behnken response surface methodology. The enzymes' activity at the obtained optimal conditions increased four times for Manganese peroxidase, and lignin peroxidase.
Volume 9, Issue 17 (Spring & Summer 2022)
Abstract
Ignoring the precise meaning and implications of Quranic lexicons appended to its text in various styles or registers may cause misunderstanding and inaccuracy in determining the connotation of the holy Quranic verses. The same problem has driven many Quranic commentators and translators to disregard the original meaning of the Quranic phrase Alqa al-Alwah [Tossed the Tablets] (Al-A'raf/105) and instead conceive it as a phrase that relates to Moses' (PBUH) violence and rebellion. However, this misinterpretation vividly contradicts the chastity of the holy prophets, and as a result, some scholars, following the Israiliyyat hadiths, have portrayed Moses as an impatient and furious prophet. Using a descriptive-analytical approach and dictionary and commentary resources, this research seeks to reveal the true meaning of this Quranic phrase and correct misconceptions about the holy prophet as someone who disregards God's commandments. The findings demonstrate that the root "La-qa-ya" does not have the connotation of "throwing," and the meaning retrieved from employing it in the pattern of If'al (Alqa) does not necessarily give it the sense of "throwing." The underlying practical meaning of Alqa al-Alwah is "to put down or toss," which refers to putting something from up to down in a non-insulting manner. This Quran phrase has a metaphoric connotation of "refusing to explain The Ten Commandments." An accurate translation may include both of the above-mentioned meanings. However, many Quran translators have failed to reflect both meanings simultaneously.
Volume 11, Issue 4 (Winter 2022)
Abstract
Aims: This study investigates the amount of heating load, cooling load, daylight and ventilation in different types of construction in Tehran and based on the objective function, calculates the optimal building type by considering the general form and RC(relative compactness) and Introduces the basis of WWR(window to wall ratio), states of window to wall distribution and orientation.
Methods: At first, different types of building types in Tehran were extracted. The types were arranged in a modular method and were classified after calculating the RC. Then the types were modeled and simulated using software to calculate heating load, cooling load, daylight and ventilation in different modes. For each type, 60 analysis were performed and by writing the objective function, the types were compared and the optimal types was introduced.
Findings: The types with a RC=0.95, WWR=10% and West 270, had the lowest heating and cooling load. Although it has a minimum energy load, it doeschr('39')nt have maximum daylight and ventilation. For this purpose, after equalizing the unit and writing the target function, a building types with a RC=0.54, WWR=40% and Uniform 180 with the lowest energy consumption and the highest amount of daylight and ventilation was selected as the optimal form.
Conclusion: Although the building types with high RC has the least load of heating and cooling, but considering other variables, these types is not optimal in climatic performance. Therefore, the weight coefficient of variables in the objective function is very important for deciding on the energy consumption of building types.
