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Open access

M.R. Ahsan, M.T. Islam, M. Habib Ullah, H. Arshad and M.T. Ali

Abstract

In this article, a simple design of rectangular microstrip feed planar antenna with wide arcs and square shape slot is proposed for Radio Frequency Identification (RFID),Worldwide Interoperability for Microwave Access (WiMAX) and C/X-band wireless communications. The prototype of the antenna has been fabricated 1.0 mm thick ceramic filled bioplastic substrate by using optimal dimension obtained from design/simulations and antenna performances are experimentally tested. The experimental results confirm the impedance bandwidths for S11 ≤ −10 dB are of 712 MHz (0.355-1.067 GHz), 1.38 GHz (2.92-4.3 GHz) and 2.46 GHz (6.55-9.01 GHz) for 0.788, 3.34 and 8.01 GHz band respectively. The proposed antenna shows almost steady and symmetrical radiation patterns for all three bands with the maximum gains of 1.37, 2.8 and 3.56 dBi respectively. Based on the antenna performances, it can successfully cover the frequency band requirement for RFID, WiMAX and C/X-band applications.

Open access

Ahsan Nazir, Tanveer Hussain, Ali Afzal, Sajid Faheem, Waseem Ibrahim and Muhammad Bilal

Abstract

The aim of this study was to develop statistical models for predicting the air permeability and light transmission properties of woven cotton fabrics and determine the level of correlation between the two parameters. Plain woven fabrics were developed with different warp and weft linear densities, ends per inch and picks per inch. After desizing, scouring, bleaching, drying and conditioning, the air permeability and light transmission properties of the fabric samples were determined. Regression analysis results showed statistically significant effect of the fabric ends, picks and warp linear density on both the fabric air permeability and light transmission. Correlation analysis was performed to analyze the relation between the fabric air permeability and light transmission. A linear equation was also formulated to find the fabric air permeability through transmission of light intensity. A fitted line plot between the air permeability and light transmission exhibited significant correlation with R-sq. value of 96.4%. The statistical models for the prediction of fabric air permeability and light transmittance were developed with an average prediction error of less than 7%.

Open access

Ahsan Nazir, Tanveer Hussain, Qummer Zia and Muhammad Ali Afzal

Abstract

Cotton is one of the most commonly used fibres for making knitwear. Some of the limitations of pure cotton knits include their tendency to shrink, relatively limited durability, and poor wash and wear properties. In order to overcome these limitations knitwear are also produced from polyester and cotton blends, however, at the cost of reduction in comfort properties. The objective of this study was to improve the thermo-physiological comfort properties of knits made from polyester/cotton (P/C) blends through simple chemical and biological treatments. The specimens of P/C knits were subjected to treatments with caustic soda solutions and the cellulase enzymes. It was found that the air permeability and perspiration management properties of P/C knits can be significantly improved by appropriate caustic treatment. However, the biological treatment with cellulase enzymes is comparatively less effective in making any improvement in the thermo-physiological comfort properties of P/C knits.

Open access

M. Ahsan, M.M. Hussain, A. Farooq, I. Khaliq, J. Farooq, Q. Ali and M. Kashif

ABSTRACT.

Drought stress is limiting global crop production more seriously than ever because of rapid change in global climate. Present investigations were made with a view to understand the traits which can be used as selection criteria for drought tolerance in maize at seedling stage. For this purpose twenty-five maize inbred lines were evaluated under water deficit conditions for traits like fresh shoot weight, fresh shoot length, fresh root length, fresh root weight, leaf venation, stomatal frequency and epidermal cell size. Significant differences were found among the genotypes for various physio-genetic traits. The genotypes 20P2-1, L5-1, 150P2-1, 70NO2-2, 150P1 and L7-2 were found good performer and may be exploited for developing drought tolerant synthetics and hybrids. Fresh shoot length and fresh root weight found overall direct and indirect contributor in fresh shoot weight and they were positive and significantly correlated with fresh shoot weight. Stomatal frequency and epidermal cell size had significantly decreasing direct and indirect effects on fresh shoot weight and significant genetic correlation with it. These results suggested that fresh shoot length and fresh root weight (Increased) stomatal frequency and epidermal cell size (decreased) might be used as selection criterion while selection for high fresh shoot yield under drought conditions.

Open access

Nouman Rafiq, Waqar A.A. Syed, Aulia Rifada, M. Asad Ghufran, Ijaz-Ur-Rehman Shah, Ahsan Ali and Wiqar Hussain Shah

Abstract

We report a simple approach for synthesizing monodispersed, crystalline and size-tunable tin sulfide nanoparticles for environment friendly next generation solar cell applications. Both SnS and SnS2 nanoparticles could be a potential nanomaterial for solar cells. The structural, morphological, thermal and optical properties were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), diffuse reflectance spectroscopy (DRS) and Fourier transform infrared spectroscopy (FT-IR). The XRD spectra revealed hexagonal and orthorhombic phases of SnS and SnS2 nanoparticles, respectively, where the grains size ranged from 11 nm to 30 nm. The weight percentage as a function of temperature was determined using TGA analysis. Functional groups were observed by FT-IR. The energy bandgap was determined as 1.41 eV showing usefulness of the nanoparticles in next generation environmental friendly solar energy applications.