Graduate University of Advanced Technology

About: Graduate University of Advanced Technology is a education organization based out in Kerman, Iran. It is known for research contribution in the topics: Carbon paste electrode & Electrochemical gas sensor. The organization has 890 authors who have published 2169 publications receiving 31027 citations.

Uniform Damping Ratio for Non-classically Damped Hybrid Steel Concrete Structures

Abstract: Steel–concrete hybrid systems are used in buildings, in which a steel structure has been placed on a concrete structure to make a lighter structure and have a faster construction. Dynamic analysis of hybrid structures is usually a complex procedure due to various dynamic characteristics of each part, i.e., stiffness, mass and especially damping. Dynamic response of hybrid structures has some complications. One of the reasons is the different stiffness of the two parts of structure and another reason is non-uniform distribution of materials and their different features such as damping in main modes of vibration. The available software is not able to calculate damping matrices and analyze these structures because the damping matrix of these irregular structures is non-classical. Also an equivalent damping should be devoted to the whole structure and using the available software. In the hybrid structures, one or more transitional storeys are used for better transition of lateral and gravity forces. In this study, an equation has been proposed to determine the equivalent uniform damping ratio for hybrid steel–concrete buildings with transitional storey(s). In the proposed method, the hybrid structure containing concrete, steel and transitional storeys appropriately substituted with 3-DOF structure. A wide range of eigenfrequency and mass ratios is examined for each ratio pair, and given the characteristics of the primary system, the complete 3-DOF structure can be formed. Equivalent uniform damping ratio is derived by means of a semi-empirical error minimization procedure. The multiple nonlinear regressions are used for determination of equations of modal damping ratios of hybrid buildings.

Optimal Slope-Angles to Determine Maximum Solar Energy Gain for Solar Collectors Used in Iran

Abstract: The aim of this paper is providing atlases to determine maximum solar energy gain and optimum slope angle of solar collectors for Iran. To achieve this purpose, first, the daily, monthly, seasonally and yearly optimum slope and azimuth angles of solar collectors are determined for 30 Iranian cities and the gain of energy is calculated in the mentioned conditions. Then, the atlas of the optimum slope angle and the contour atlas of the maximum energy gain is provided. The Geographic Information System (GIS) is used to outline the maps. These atlases are essentials tools to find the best location for constructing different solar systems. The results show that the energy gain of the collector when it is adjusted at the daily optimum slope angle is almost the same compared with the case at the monthly optimum slope angle. Therefore, the map is provided for the energy gain when the collectors are mounted at the monthly optimum slope angle. The map of optimum slope angle is outlined for the fixed collector used for the entire year due to the high use of fixed collectors. Furthermore, the results show that Iran can be divided into five zone and the areas with the same latitude and climate have almost the same optimum slope angle.

Evaluation of lithium serum level in multiple sclerosis patients: A neuroprotective element.

Abstract: Introduction It has been claimed that continuous and high production of nitric oxide (NO) and its metabolites may be involved in the pathogenesis of several neurological disorders such as multiple sclerosis. A number of studies have demonstrated that lithium regulates NO levels in disorders of the central nervous system. The aim of this study was to investigate whether NO as a marker of disease activity is correlated with lithium deficiency in relapsing remitting multiple sclerosis (RR-MS). Methods This case-controlled study comprised 44 patients with RR-MS and 43 healthy subjects matched by age, gender, smoking status, and body mass index. The Griess reaction was used to measure the NO metabolites, nitrite and nitrate in serum. In addition serum lithium levels were measured using atomic absorption spectrometry method. The mean serum NO concentrations in the groups RR-MS and the control were 18.5 ± 3.1 µM and 15.5 ± 2.9 µM, respectively. Data analysis showed a statistically significant difference between subjects with RR-MS and the control group (p Conclusion: The present findings suggest that lithium deficiency may upregulates NO production in RR-MS. Further studies with larger samples are needed to confirm the effects of lithium treatment on NO pathway and its association with synaptic plasticity in RR-MS patients.

Synthesis of a Zeolitic Imidazolate–Zinc Metal–Organic Framework and the Combination of its Catalytic Properties with 2,2,2-Trifluoroethanol for N-Formylation

Abstract: A novel protocol is reported for the N-formylation of amines with formic acid by using the nanoporous zeolitic imidazolate framework ZIF-8 as a heterogeneous catalyst in 2,2,2-trifluoroethanol.