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Open access

lfsana Karim, M.S. Khan, M.M. Alam, M.A. Rouf, M. Ferdows and E.E. Tzirtzilakis

Abstract

In the present computational study, the inclined angle effect of unsteady heat and mass transfer flow through salt water in an ocean was studied. The governing equations together with continuity, momentum, salinity and temperature were developed using the boundary layer approximation. Cartesian coordinate system was introduced to interpret the physical model where x-axis chosen along the direction of salt water flow and y-axis is inclined to x-axis. Two angle of inclination was considered such as 90° and 120°. The time dependent governing equations under the initial and boundary conditions were than transformed into the dimensionless form. A numerical solution approach so-called explicit finite difference method (EFDM) was employed to solve the obtained dimensionless equations. Different physical parameter was found in the model such as Prandtl number, Modified Prandtl number, Grashof number, Heat source parameter and Soret number. A stability and convergence analysis was developed in this study to describe the aspects of the finite difference scheme and this analysis is significant due to accuracy of the EFDM approach. The convergence criteria were observed to be in terms of dimensionless parameter as Pr ≥ 0.0128 and Ps ≥ 0.016. The distributions of the temperature and salinity profiles of salt water flow over different time steps were investigated for the effect of different dimensionless parameters and shown graphically.

Open access

N. A. Khan, A. Shaikh, M. A. Zahoor Raja and S. Khan

Abstract

In this article, Legendre simulated annealing, neural network (LSANN) is designed for fuzzy fractional order differential equations, which is employed on fractional fuzzy initial value problem (FFIVP) with triangular condition. Here, Legendre polynomials are used to modify the structure of neural networks with a Taylor series approximation of the tangent hyperbolic as activation function while the network adaptive coefficients are trained in the procedure of simulated annealing to optimize the residual error. The computational results are depicted in terms of numerical values to compare them with previous results.

Open access

Yashashri Patil, S. Khirwadkar, S. M. Belsare, Rajamannar Swamy, M. S. Khan, S. Tripathi and K. Bhope

Abstract

This paper is focused on various aspects of the development and testing of water cooled divertor PFCs. Divertor PFCs are mainly designed to absorb the heat and particle fluxes outflowing from the core plasma of fusion devices like ITER. The Divertor and First Wall Technology Development Division at the Institute for Plasma Research (IPR), India, is extensively working on development and testing of divertor plasma facing components (PFCs). Tungsten and graphite macro-brush type test mock-ups were produced using vacuum brazing furnace technique and tungsten monoblock type of test mock-ups were obtained by hot radial pressing (HRP) technique. Heat transfer performance of the developed test mock-ups was tested using high heat flux tests with different heat load conditions as well as the surface temperature monitoring using transient infrared thermography technique. Recently we have established the High Heat Flux Test Facility (HHFTF) at IPR with an electron gun EH300V (M/s Von Ardenne Anlagentechnik GmbH, Germany) having maximum power 200 kW. Two tungsten monoblock type test mock-ups were probed using HHFTF. Both of the test mock-ups successfully sustained 316 thermal cycles during high heat flux (HHF) tests. The test mock-ups were non-destructively tested using infrared thermography before and after the HHF tests. In this note we describe the detailed procedure used for testing macro-brush and monoblock type test mock-ups using in-house transient infrared thermography set-up. An acceptance criteria limit was defined for small scale macro-brush type of mock-ups using DTrefmax value and the surface temperature measured during the HHF tests. It is concluded that the heat transfer behavior of a plasma facing component was checked by the HHF tests followed by transient IR thermography. The acceptance criteria DTrefmax limit for a graphite macro-brush mock-up was found to be ~3°C while for a tungsten macro-brush mock-up it was ~5°C.

Open access

M. Sarfraz, S.A. Khan, A. Moosa, A. Farzand, U. Ishaq, I. Naeem and W.A. Khan

Abstract

In vitro antifungal potential of Trichoderma isolates, selective botanical extracts and fungicides against A. solani was evaluated. Trichoderma isolates, i.e. T. harzianum, T. viride and T. hamatum, were tested for their antifungal effect by dual culture technique at 48, 96, 144 and 172 hrs. T. hamatum produced the highest inhibition of A. solani in vitro, followed by T. hazianum and T. viride after 172 hrs. Methanolic leaf extracts of Elettaria cardamomum, Syzygium aromaticum, Curcuma longa and root extract of Parthenium hysterophorus showed up to 100% inhibition of A. solani, compared to control, while methanolic stem and leaf extracts of P. hysterophorus produced up to 90% inhibition of the pathogen. In vitro, six different systemic fungicides Triger 25% EC (Tebuconazole), Solex (Carbendazim 40% + Triadimefon 10%), Dew (Difenoconazole), Amistor Top SC (Azoxystrobin + Difenoconazole), Corel 25% EC (Difenoconazole), Reflex (Difenoconazole + Propiconazole) were tested against A. solani at 5, 10 and 15 ppm concentrations after 48, 96, 144 and 172 hrs. Corel and reflex at all concentrations produced best growth inhibition of A. solani. The inhibition was maximum by all fungicides at 15 ppm after 172 hrs. All fungicides had a promising inhibitory effect on A. solani, except Solex. It can be concluded from the present investigation that a combination of these strategies can be used in integrated disease management of A. solani on potato.

Open access

O. Naseer, J.A. Khan, M.S. Khan, M.O. Omer, G.A. Chishti, M.L. Sohail and M.U. Saleem

Abstract

Aflatoxins are secondary metabolites produced by Aspergillus spp. which are injurious to animals and humans The aim of this study was to determine the effects of aflatoxin B1 (AFB1) on Average Daily Feed Intake (ADFI), Average Daily Weight Gain (ADWG), haematological and serum biochemical responses of Bovine Calves and to determine the comparative efficacy of two different liver tonics against AFB1. Twenty seven calves were selected from herd and divided into 3 groups. All calves were fed with 1.0 mg/kg AFB1 for a period of 10 days. After that they were fed with liver tonics: Silymarin fed at a rate of 600 mg/kg and Choline chloride 500 mg/kg for 7 days. The results indicate that the ADFI and ADWG of AFB1 treated calves decreased significantly. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN) and creatinine significantly increased due to AFB1. In haematology the total erythrocyte count (TEC), total leukocyte count (TLC), haemoglobin concentration (HGB), haematocrit levels (HCT), mean corpuscular haemoglobin (MCH), mean corpuscular volume (MCV) and mean corpuscular haemoglobin concentration (MCHC), lymphocyte %, neutrophil % and monocyte % significantly decreased in AFB1 treated calves after 10 days of feeding. Both liver tonics significantly (p<0.05) improved all the parameters, including ADFI, ADWG, hematologial and serum biochemical test. However, Silymarin comparatively more efficiently ameliorate the effects induced by AFB1 than choline chloride.

Open access

S. Iqbal, H.Z. Khan, Ehsanullah, N. Akbar, M.S.I. Zamir and H.M.R. Javeed

Abstract

A field experiment was conducted to study the effect of different nitrogen management methods on yield, yield components and quality attributes of maize hybrids (single cross-6142 and double cross-4444) under irrigated conditions. Nitrogen dose is met either by PM (poultry manure) or urea according to each treatment. PM was incorporated at the time of presowing irrigation whereas fertigation method at knee height stage and foliar spray at flowering were use for the application of urea. Results showed that plant height, cob diameter, number of grains per cob, grain yield and biological yield were significantly affected by the hybrids. Significantly, higher plant height, cob diameter, number of grains per cob, grain yield and biological yield were produced by single cross-6142. There was no significant difference occur between both hybrids on seed oil and protein contents. N management by the application of T3 (60% N from PM + 38.5% N from urea through fertigation + 1.5% N from urea through foliar application) produced significantly more plant height, cob diameter, number of grains per cob, grain yield, biological yield, seed protein and seed oil contents. The interaction of single cross-6142 and T3 (60% N from PM + 38.5% N from urea through fertigation + 1.5% N from urea through foliar application) was found superior in production of more plant height, cob diameter and number of grains per cob. However, interaction between maize hybrids and N application methods for grain yield, biological yield, seed protein and oil contents was reported nonsignificant. It can be concluded that single cross hybrid-6142) and T3 (60% N from PM, 38.5% N from urea through fertigation and 1.5% N from urea through foliar application) could be used successfully for improving maize yield under the irrigated conditions.

Open access

K. Ullah, M. S. Khan, M. T. Lakhiar, A. A. Vighio and S. Sohu

Abstract

The problem of delay is a regular phenomenon in construction projects all around the world and the Malaysian building projects has no exclusion. The aim of this paper is to determine and rank the effects of delay in Malaysian building projects with respect to their Relative Importance Index. Literature review and questionnaire survey were used to gather data for this study. A thorough literature review was performed to identify the common effects of delays in building construction projects. A questionnaire was distributed among key project participants; contractors, clients and consultants, to rank the effects of delay in Malaysian building projects based on the perception of survey respondents. In total 300 questionnaires were distributed, as a result of 240 questionnaires were received. The collected data of questionnaire survey was analysed using statistical software SPSS. In total, 17 effects of the delays have been determined and findings from the survey revealed that time overrun, cost overrun, dispute, loss of profit, arbitration, claims, contract termination, litigation, poor quality of work, and total project abandonment were the main effects of delay in Malaysian building projects. The findings of this study might encourage construction stakeholders to focus on the issue of delays in building projects.

Open access

B.V. Omidiji, R.H. Khan and M.S. Abolarin

Abstract

The influence of the refractory coating which is a mixture of silica flour and kaolin on the surface roughness of the plate castings produced using evaporative patterns had been considered in this work. The kaolin was used as a binder and ratio method was employed to form basis for the factorial design of experiment which led to nine runs of experiments. Methyl alcohol at 99% concentration was used as the carrier for the transfer of the coating to the surface of the patterns. Pouring temperature was observed as a process parameter alongside the mix ratios of the coating. Attempts were made to characterize the refractory coating by using two methods; differential thermal analysis (DTA) and X-ray diffraction. Attempt was also made to characterize the casting material. Gating system design was done for the plate casting to determine the correct proportions of the gating parameters in order to construct the gating system properly to avoid turbulence during pouring of liquid metal. A digital profilometer was used to take the measurements of the surface roughness. It was observed that the mix ratio 90% silica flour-10% kaolin produced the lowest value of the surface roughness of the plate castings and had the lowest material loss in the DTA test. The pouring temperature of 650°C produced best casting.

Open access

J. Reddy, A. Singh, S. Joshi, M. Khan and J. Saxena

Abstract

DNA topoisomerases are ubiquitous enzymes which are involved in replication, transcription, recombination and repair of nucleic acids. DNA topoisomerase II of filarial parasite Setaria cervi was purified to homogeneity by use of cation exchange and affinity chromatography. The purified enzyme migrated on SDS-PAGE as a single band with molecular weight of ∼80 kDa and native molecular weight of the enzyme was found to be 175 kDa indicating the dimeric nature of the protein. Topo II of S. cervi required ATP and dATP for its activity and optimal activity was observed at 1.0 mM ATP concentration. The filarial enzyme also utilized nucleotides, namely GTP, UTP and CTP for its activity. The divalent metal ions requirement of the enzyme showed that beside Mg+2 other ions viz., Ca+2, Mn+2, Cu+2 and Sr+2 were also utilized as cofactor for the activity. Antifilarial compounds ivermectin and diethylcarbamazine inhibited 100 % topo II activity at 100 μM concentration but suramin showed similar effect at 20 μM concentration. Nalidixic acid and novobiocin exhibited 100 % inhibition of the enzyme activity while mAMSA and etoposide inhibited the activity to different extents at 100 μM concentration. In view of significant differences in properties exhibited by the filarial topoisomerase as compared to other parasitic and eukaryotic topoisomerases, the filarial topoisomerase can be usefully exploited to devise new antifilarial compounds.

Open access

Nadeem Siddiqui, Arpana Rana, Suroor Khan, S. Haque, M. Arshad, Sharique Ahmed and Waquar Ahsan

Synthesis and preliminary screening of benzothiazol-2-yl thiadiazole derivatives for anticonvulsant activity

Various N-(5-chloro-6-substituted-benzothiazol-2-yl)-N'-(substituted phenyl)-[1,3,4]thiadiazole-2,5-diamines (5a-t) were designed and synthesized starting from substituted acetophenones. Structures of all the compounds were confirmed on the basis of spectral and elemental analyses. All the newly synthesized compounds were screened for their anticonvulsant activity and were compared with the standard drug phenytoin sodium. Interestingly, all the compounds showed protections against seizures in the range 50-100% indicative of the promising nature of the compounds against seizure spread. Compounds 5b and 5c showed complete protection against MES induced seizures.