Mechanical and Durability Properties of Sustainable Self-compacting Concrete with Waste Glass Powder and Silica Fume

Environmental protection approach has caused to ignore the conditions and the possibility of using solid waste as a substitute for concrete. In this research, the effect of glass powder in percentages of 0-30 (in steps of 7.5%) and micro-silica (10% as a constant) as a substitute for cement is investigated on efficiency, compressive strength, tensile strength, and bending strength. surface water absorption, capillary water absorption, and freeze/thaw cycle are paid. The results showed that the use of glass powder leads to increases the fluidity and properties of fresh concrete. The mechanical parameters decrease slightly when 30% of cement is replaced with glass powder

Biodiesel synthesis using clinoptilolite-Fe3O4-based phosphomolybdic acid as a novel magnetic green catalyst from salvia mirzayanii oil via electrolysis method : optimization study by Taguchi method

Abstract: Objective of current study is the synthesis of biodiesel from salvia mirzayanii oil using phosphomolybdic acid (H3PMo12O40, HPA) supported on the clinoptilolite-Fe3O4. The prepared catalyst properties were determined by different analyses including FESEM, EDX, TEM, FTIR, and VSM, and its performance was studied in the process of biodiesel production. Four key factors effects like reaction time, catalyst weight, methanol to oil molar ratio, and temperature were investigated and optimized by the Taguchi method. In this method, the significance of effective factors on the biodiesel yield is controlled by analysis of variance (ANOVA). The highest biodiesel yield was found 80% at operating conditions of 0.5 wt.% HPA/clinoptilolite-Fe3O4 catalyst, methanol/oil ratio of 12:1, and temperature of 75 °C at 8 hours. The GC-MS analysis identified the fatty acid profile of salvia mirzayanii oil and biodiesel, the FTIR spectrum was performed to ensure biodiesel formation from the final product. The H-NMR analysis compared the properties of oil and biodiesel. The physicochemical properties of the produced biodiesel revealed that the biodiesel has the same properties as the diesel..

Construction of Evaluative Meanings by Kurdish-Speaking Learners of English: A Comparison of High- and Low-Graded Argumentative Essays

Academic writing ability is an important goal that learners of English as a Second Language (ESL) or English as a Foreign Language (EFL) try to attain. While ESL students’ academic writings have been widely explored, owing to few studies investigating appraisal resources in EFL students’ argumentative writing, the gap still exists about EFL students’ academic writing. This study aimed to see how Kurdish-speaking learners of English employ appraisal resources in their writings. It further aimed to explore whether the appraisal framework can be utilized as an assessment scale for evaluating the students’ argumentative writing. To this end, the study investigated the argumentative essays written by 15 bilingual Kurdish-Iranian graduates of English within the framework of the appraisal theory. The instruments applied in this study consisted of a modified rating scale for assessing the essays in terms of the macrostructures exploited in them and the framework for the analysis of appraisal resources. Quantitative findings revealed high-graded essays employ more attitudinal items and fewer monoglossic resources than low-graded ones. Qualitatively, the high-graded essays articulated attitudinal values in nominal forms and sometimes in a backgrounded manner while these values were mostly presented by surge of feelings and in a foregrounded way in the low-graded essays. Regarding engagement, unlike the high-graded essays, the low-graded ones were poor in recognizing other voices and alternative positions. Inspired by the strength of the appraisal model evaluating writing, results suggest that high-graded essays are successful in positioning readers attitudinally and clarifying the ethical message to readers

Risk factors for COVID-19 severity and mortality among inpatients in Southern Iran

Introduction: COVID-19 is a highly contagious respiratory disease and many factors can affect its severity and mortality. This study aimed to investigate the risk factors associated with the severity and mortality of COVID-19. Methods: In this study, 311 cases with COVID-19 approved by the CORONA database in the Center for Disease Control and Prevention (CDC) of Shiraz University of Medical Sciences were selected using a random systematic sampling method. The study data were collected through interviews and phone calls. Results: The mean age of the participants was 45.82±17.92 years, and the male to female ratio was 1.57:1. In addition, the Case Fatality Rate (CFR) was 4.50%, and the disease was severe in 47.5% of the cases. The most common clinical symptoms were cough (39.22%), fever (31.83%), and dyspnea (24.76%). The severity of COVID-19 was significantly associated with age and history of Cardiovascular Disease (CVD). Besides, the mortality of COVID-19 was significantly related to age, gender, hypertension, CVD, and Chronic Kidney Disease (CKD). The mean interval between the onset of the first symptom and referral to health center was 3.02±2.82 days. Additionally, the mean interval between the referral to health centers and testing was 0.88±2.20 days. Conclusion: Older patients and those who had CVD needed more careful healthcare and early intervention to prevent the exacerbation of COVID-19. Furthermore, the interval between the onset of the first symptom and testing was relatively long. Overall, early diagnosis, isolation, and treatment of patients were found to be essential to control COVID-19

Application of nanofluids for treating fines migration during hydraulic fracturing: Experimental study and mechanistic understanding

 Hydraulic fracturing has emerged as one of the best and most economic methods for enhancing oil recovery from low permeability reservoirs such as shale gas reservoirs. However, its performance will be negatively affected by fines migration due to hydraulic fracturing process. In the present study, it has been tried to experimentally investigate the efficiency of a synthesized Nanosilica particles in reducing fines migration for the first time in literature. To this end, two sets of static and dynamic experiments, namely glass bead funnel test and core displacement analysis, were implemented, respectively. In the static test, increasing the soaking time and addition of Nanosilica led to the clearer effluent fluid, resulting in less concentrations of clay particles in solution. When the mixture of Nanosilica and glass beads was available in the solution, a higher differential pressure was obtained during dynamic condition in comparison to only glass beads, which means the lower permeability of the porous media. Moreover, DLVO theory was applied to demonstrate the clay particles absorption on the sand proppants surfaces.  Consequently, it was observed that the use of Nanosilica particles mixed with sand proppant can effectively reduce fines migration; thereby, it can enhance hydraulic performance of the fracturing operation.Cited as: Moghadasi, R., Rostami, A., Hemmati-Sarapardeh, A. Application of nanofluids for treating fines migration during hydraulic fracturing: Experimental study and mechanistic understanding. Advances in Geo-Energy Research, 2019, 3(2): 198-206, doi: 10.26804/ager.2019.02.0

Application of nanofluids for treating fines migration during hydraulic fracturing: Experimental study and mechanistic understanding

Hydraulic fracturing has emerged as one of the best and most economic methods for enhancing oil recovery from low permeability reservoirs such as shale gas reservoirs. However, its performance will be negatively affected by fines migration due to hydraulic fracturing process. In the present study, it has been tried to experimentally investigate the efficiency of a synthesized Nanosilica particles in reducing fines migration for the first time in literature. To this end, two sets of static and dynamic experiments, namely glass bead funnel test and core displacement analysis, were implemented, respectively. In the static test, increasing the soaking time and addition of Nanosilica led to the clearer effluent fluid, resulting in less concentrations of clay particles in solution. When the mixture of Nanosilica and glass beads was available in the solution, a higher differential pressure was obtained during dynamic condition in comparison to only glass beads, which means the lower permeability of the porous media. Moreover, DLVO theory was applied to demonstrate the clay particles absorption on the sand proppants surfaces. Consequently, it was observed that the use of Nanosilica particles mixed with sand proppant can effectively reduce fines migration; thereby, it can enhance hydraulic performance of the fracturing operation

Review The approach of Customary Rules of International Environmental Law in Climate Change

Today, custom is of great importance in the world community and means a general procedure that has been accepted as a legal rule, and such a custom creates a mandatory legal rule that is implemented in relations between governments and has two material and spiritual elements. Unfortunately, despite the fact that many treaties, declarations and international documents have been issued in relation to the environment, we still see that the environmental situation of the planet is becoming more and more unfavorable, so the international community has principles abo0ut International environmental law has been drafted. With global warming and climate change, governments have come together to find a solution. Now we want to examine what the relationship is between customary international law and international environmental law, and to what extent the rules of customary international law can be effective in preventing environmental degradation and favoring climate change. International custom, if accompanied by the necessary publicity and acceptance, can have an aspect of law for the international community. Thus, the normalization of climate commitments is useful where governments' practices are not accountable and do not provide appropriate rules, and can be cited as a stimulus for governments to legislate

Simple and fast Development and validation of High Performance Liquid Chromatography Method with UV determination of thiopental in rat plasma

Objective: Now days old agent thiopental return to hot-topic of research as new Model of neuropharmacology study. Because of this reason simple, fast and cost benefit method of determination this agent comes an issue in area pharmacokinetic and pharmacodynamics (PK-PD) area of research. Previous study was focus on human plasma and pilot study showed there is differentiation between human and rat plasma. Methods: Separation were perform Nuleodur C18 ec HPLC column (250×4.0×5µm), using a mixture of acetonitrile; potassium; dihydrogen phosphate buffer (10mM, PH 2.7) as mobile phase delivered at flow rate 1.2 ml/minute. 280 nm and room temperature was selected for detection of thiopental and 1-Naphtylamine as internal standard. Plasma sample (100µl) were treated with 180µl precipitation solution and 20µl of internal standard. After the mixture were vortex and centrifuge at 1000 g, finally 40µl of clear supernatant was directly injected into 20µl loop of HPLC apparatus. Calibration curve were fitted by Peak area ratio of thiopental to internal standard. All stage of blood collection was under supervision of Ahvaz ethical committee. Results: Thiopental and internal standard retention time were at 8.3 and 14.5 minute, respectively. 0.5 µg/ml was level of limit of quantification, of our method. 99.4 to 100.3 was range of Accuracy of methods. inter- and intraday precisions were 4-19 % and 6-8%, respectively. A good relationship in the form of a power was found (r2=0.999). Conclusions: the presented simple fast and cost benefit method is great accurate, precise and sensitive for determination of thiopental in plasma of rat

Beyond Spheroids and Discs: Classifications of CANDELS Galaxy Structure at 1.4 < z < 2 via Principal Component Analysis

Important but rare and subtle processes driving galaxy morphology and star-formation may be missed by traditional spiral, elliptical, irregular or S\'ersic bulge/disk classifications. To overcome this limitation, we use a principal component analysis of non-parametric morphological indicators (concentration, asymmetry, Gini coefficient, $M_{20}$, multi-mode, intensity and deviation) measured at rest-frame $B$-band (corresponding to HST/WFC3 F125W at 1.4 $10^{10} M_{\odot}$) galaxy morphologies. Principal component analysis (PCA) quantifies the correlations between these morphological indicators and determines the relative importance of each. The first three principal components (PCs) capture $\sim$75 per cent of the variance inherent to our sample. We interpret the first principal component (PC) as bulge strength, the second PC as dominated by concentration and the third PC as dominated by asymmetry. Both PC1 and PC2 correlate with the visual appearance of a central bulge and predict galaxy quiescence. PC1 is a better predictor of quenching than stellar mass, as as good as other structural indicators (S\'ersic-n or compactness). We divide the PCA results into groups using an agglomerative hierarchical clustering method. Unlike S\'ersic, this classification scheme separates compact galaxies from larger, smooth proto-elliptical systems, and star-forming disk-dominated clumpy galaxies from star-forming bulge-dominated asymmetric galaxies. Distinguishing between these galaxy structural types in a quantitative manner is an important step towards understanding the connections between morphology, galaxy assembly and star-formation.Comment: 31 pages, 24 figures, accepted for publication in MNRA