Alternatives to Enhance Flat Slab Ductility

Mohamed Husain,Ahmed S. Eisa,Ramy Roshdy 한국콘크리트학회 2017 International Journal of Concrete Structures and M Vol.11 No.1

Flat slab systems are vastly used in multi-story buildings because of their savings in story height and construction time, as well as for their flexibility in architectural remodeling. However, they frequently suffer brittle punching-shear failure around columns, especially when subjected to lateral loads. Therefore, seismic codes labeled flat slabs as non-ductile systems. This research goal is investigating some construction alternatives to enhance flat slab ductility and deformability. The alternatives are: adding different types of punching-shear reinforcement, using discreet fibers in concrete mixes, and increasing thickness of slab around columns. The experimental study included preparation and testing of seven half-scale interior slab-column connections up to failure. The first specimen is considered a reference, the second two specimens made of concrete mixes with different volumetric ratios of polymer fibers. Another three specimens reinforced with different types of punching-shear reinforcement, and the last specimen constructed with drop panel of inverted pyramidal shape. It is found that using the inverted pyramid-shape drop panel of specimen, increases the punching-shear capacity, and the initial and the post-cracking stiffnesses. The initial elastic stiffnesses are different for all specimens especially for the slab with closed stirrups where it is experienced the highest initial stiffness compared to the reference slab.

Alternatives to Enhance Flat Slab Ductility

Husain, Mohamed,Eisa, Ahmed S.,Roshdy, Ramy Korea Concrete Institute 2017 International Journal of Concrete Structures and M Vol.11 No.1

Flat slab systems are vastly used in multi-story buildings because of their savings in story height and construction time, as well as for their flexibility in architectural remodeling. However, they frequently suffer brittle punching-shear failure around columns, especially when subjected to lateral loads. Therefore, seismic codes labeled flat slabs as non-ductile systems. This research goal is investigating some construction alternatives to enhance flat slab ductility and deformability. The alternatives are: adding different types of punching-shear reinforcement, using discreet fibers in concrete mixes, and increasing thickness of slab around columns. The experimental study included preparation and testing of seven half-scale interior slab-column connections up to failure. The first specimen is considered a reference, the second two specimens made of concrete mixes with different volumetric ratios of polymer fibers. Another three specimens reinforced with different types of punching-shear reinforcement, and the last specimen constructed with drop panel of inverted pyramidal shape. It is found that using the inverted pyramid-shape drop panel of specimen, increases the punching-shear capacity, and the initial and the post-cracking stiffnesses. The initial elastic stiffnesses are different for all specimens especially for the slab with closed stirrups where it is experienced the highest initial stiffness compared to the reference slab.

Comparative toxicity study on classical and modified version of Jawarish Jalinoos (a traditional Unani formulation) in rats

Gulam Mohammed Husain,Syed Shoeb Ahmed,Misbahuddin Azhar,Javed Inam Siddiqui,Mohammad Abdul Waheed,Munawwar Husain Kazmi 한국한의학연구원 2017 Integrative Medicine Research Vol.6 No.1

Background: Jawarish Jalinoos (JJ) is a classical semisolid traditional Unani formulation clinically used for the treatment of weakness of vital organs, liver, and stomach. Although JJ has been widely used clinically for several decades, no scientific report is available for its safety. Methods: JJ and its sugar-free tablet version (SFJJ; formulated to target diabetic population) were assessed for safety in rats. Ninety-day repeated dose oral toxicity study was performed as per the Organisation for Economic Co-operation and Development Guideline 408. JJ was orally administered at the dose of 2000 mg/kg bw/d, whereas SFJJ was orally administered at the doses of 506 mg/kg body weight (bw)/d, 1012 mg/kg bw/d, and 2024 mg/kg bw/d for 90 days. The animals were periodically observed for clinical signs of toxicity, mortality, morbidity, body weight changes, and feed consumption. At the end of the study, hematology, clinical biochemistry, electrolytes, gross pathology, relative organ weight, and histological examination were performed. Results: Treatment with SFJJ and JJ showed no significant differences in body weight gain, feed consumption, hematology, clinical biochemistry, and serum electrolytes. No gross pathological findings and differences in relative organ weights were observed between control and drug treated rats. Histological examination revealed no toxicologically significant abnormalities related with SFJJ or JJ treatment. Conclusion: The 90-day repeated dose oral toxicity study demonstrates that the no observed adverse effect level of SFJJ and JJ is greater than 2024 mg/kg bw/d and 2000 mg/kg bw/d (p.o.) in rats, respectively. Both formulations were found to be safe up to the tested dose levels and experimental conditions, and therefore safe for clinical use as specified in the literature.

Post-Heating Response of Concrete-Filled Circular Steel Columns

Husain Abbas,Yousef Al-Salloum,Saleh Alsayed,Mohammed Alhaddad,Rizwan Iqbal 대한토목학회 2017 KSCE JOURNAL OF CIVIL ENGINEERING Vol.21 No.4

Concrete-Filled Steel Tubular (CFST) columns are increasingly becoming popular for carrying heavy loads. One of the major concerns for such columns has always been the exposure to fire and subsequent cooling for which different methods are adopted. This study investigates the effect of cooling regimes after exposure to elevated temperature of 600oC for three hours on axial compression behavior of concrete-filled circular stub columns. The experimental program involves the testing of thirty columns consisting of two sizes of outer steel tube. Double skin columns were also considered for the bigger diameter column. The cooling regimes considered in the study were annealing and water quenching. The columns were tested for two possible modes of load transfer viz. core loaded and composite loaded. The behavior of columns was studied in terms of ultimate load capacity, loaddeformation pattern and stresses in the materials. The ductility of concrete-filled columns was higher than that of the steel tube alone. The confinement offered by outer steel tube was less in composite loaded columns as compared to core loaded columns. The annealing was found to be slightly better than water quenching for post-fire cooling of columns.

Analysis of Relationship between O3, NO, and NO2 in Riyadh, Saudi Arabia

Mohammed Mujtaba Shareef,Tahir Husain,Bader Alharbi 한국대기환경학회 2018 Asian Journal of Atmospheric Environment (AJAE) Vol.12 No.1

For the first time in the city of Riyadh, the formation of O3 and its relationship with NO and NO2 (NOx) was investigated. Throughout the summer O3, NO, and NO2 were collected from three locations: residential, industrial, and rural areas. During the sampling period O3 concentrations exceeded 1-hour local standards a few times yet remained consistent with the standards most of the time. The O3 concentrations were observed highest in the rural location and lowest in the industrial area. The diurnal variation of NO followed a double peak: one in the morning and the other in the evening, representing the traffic pattern. Early morning NO peaks were observed in the rural location, which were attributed to the movement of NO from other locations. The O3 concentrations depicted typical pattern, increasing after sunrise and reaching its maximum during midday. The highest O3 concentrations were observed in the rural location followed by the residential and industrial. NO2 photolysis rates were 3-4 times higher compared to other similar investigations, potentially due to intense solar radiation. A strong negative correlation was observed between NOx and O3 values in the industrial location indicating photochemical activities around the industrial area were higher, likely due to additional NOx emissions from industries. Regression analysis of NOx and OX (O3 +NO2) indicated that in residential and industrial locations at nighttime there were large NOx independent regional contributions which is attributed to VOCs. The Weekend Effect was observed in the city potentially due to the production of the OH radical and subsequent reactions with VOCs implying that the area is VOC-sensitive.

Thermal performance investigation of enhanced receiver tube for concentrated solar collector

Mohammed Al-Harrasi,Afzal Husain,M. Zunaid Techno-Press 2022 Advances in energy research Vol.8 No.3

This study presents an experimental investigation of conventional and enhanced receiver tube performance for the application of a concentrated parabolic trough collector (CPC). The CPC system is fabricated and tested for the conventional and enhanced receiver tubes. The experiments were performed on both tubes for the change of flow rates. The temperature rise of the tube surface, as well as working fluid, were monitored for varying flow rates. The results were compared and discussed in view of enhanced CPC system performance. The results exhibited that the temperature rise of the working fluid passing through the tube was more in the case of the enhanced tube compared to the conventional receiver tube under the same flow rates.

Induction of Early Flowering and Fruiting in Duku Trengganu (Lansium domesticum Corr.) Using Water Management as a Tool

Kamariah Mohamed,Mohammud Che" Husain,Mohammad Isa Mohammad 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

Potential mechanism of anti-diabetic activity of Picrorhiza kurroa

Gulam Mohammed Husain,Richa Rai,Geeta Rai,Harikesh Bahadur Singh,Ajit Kumar Thakur,Vikas Kumar 셀메드 세포교정의약학회 2014 TANG Vol.4 No.4

Picrorhiza kurroa Royle ex Benth. (Scrophulariaceae) is a traditional Ayurvedic herb known as Kutki. It is used as a remedy for diabetes by tribes of North Eastern Himalayan region of India. Present study was conducted to explore the mechanism of antidiabetic activity of standardized aqueous extract of Picrorhiza kurroa (PkE). PkE (100 and 200 mg/kg/day) was orally administered to streptozotocin induced diabetic rats, for 14 consecutive days. Plasma insulin levels were measured and pancreas of rat was subjected to histopathological investigations. Glucose transporter type 4 (GLUT-4) protein content in the total membrane fractions of soleus muscle was estimated by Western blot analysis. Plasma insulin level was significantly increased along with concomitant increase in GLUT-4 content of total membrane fractions of soleus muscle of diabetic rats treated with extract. There was evidence of regeneration of β-cells of pancreatic islets of PkE treated group in histopathological examinations. PkE increased the insulin-mediated translocation of GLUT-4 from cytosol to plasma membrane or increased GLUT-4 expression, which in turn facilitated glucose uptake by skeletal muscles in diabetic rats.

Assessment of Meta-Heuristic and Classical Methods for GMPPT of PV System

M. Naseem,Mohammed Aslam Husain,Ahmad Faiz Minai,Ahmad Neyaz Khan,Mohd Amir,J. Dinesh Kumar,Arif Iqbal 한국전기전자재료학회 2021 Transactions on Electrical and Electronic Material Vol.22 No.3

Numerous global peak searching mechanisms have been proposed to solve the problem of energy loss due to partial shading of solar photovoltaic (PV) plants but still there is a great need for an effi cient and fast global maximum power point tracker (GMPPT). A detailed review of GMPPT based on various meta-heuristic and classical methods along with the basics of partial shading phenomenon, proper positioning of the PV panels, distributed MPPT, Field MPPT etc. will be of great help to the researchers. Till date, it looks like that not a single literature has covered these issues at a single place and thus, this article fi lls this gap by providing a detailed assessment, tabulated gist of the various GMPPT along with the basics of key issues related to partial shading of PV plants. Various classical and bio-inspired meta-heuristic based GMPPT methods have been compared in this literature. It is expected that this paper will prove to be a valuable asset and a complete reference for the academicians and professionals for further research and proper selection of a GMPPT technique.

Quality Control of Majoon-e-Nisyan and its Acute Oral Toxicity Study in Experimental Rats

Shaikh, Masud,Husain, Gulam M.,Naikodi, Mohammed Abdul Rasheed,Kazmi, Munawwar H.,Viquar, Uzma Cellmed Orthocellular Medicine and Pharmaceutical 2021 셀메드 (CellMed) Vol.11 No.1

The clinical condition Amnesia causes difficulty in learning new information and the inability to recall past events. It is primarily concerned with recent memory loss. Majoon-e-Nisyan (MJN) is a polyherbal Unani formulation, present in a semi-solid form. It is widely used potent drug of the Unani System of Medicine (USM) for treating Nisyan (amnesia). In the present study polyherbal Unani formulation, MJN has been studied for its quality control and acute toxicity. Standardization (quality control) of drugs deals with drug identity, drug quality and purity determination. Standardization of MJN had been done as per the Unani pharmacopoeial parameters approved by World Health Organization (WHO) - Pharmacognostical parameters, Physico-chemical parameters, high-performance thin-layer chromatography (HPTLC), microbial load, aflatoxin, and heavy metals. Solvents and chemicals used in the study were of analytical grade and used instrument were calibrated. By conducting an acute oral toxicity study in rats, the safety of MJN was assessed. The limit test method of OECD guideline 425 was followed in the study. Results of standardization and standard operating procedures (SOPs) for preparation of MJN may serve as the standard reference in the future. The data generated in the study for the quality control of MJN proved the quality of formulation and shows that MJN is not toxic in rats following acute dosing up to 2000 mg/kg bw. The data obtained in the paper for MJN may be used as a standard guideline for preparation of the formulation which can save time, cost, and resources for future research endeavours.