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Nonlinear Localization due to a Double Negative Defect Layer in a One-Dimensional Photonic Crystal Containing Single Negative Material Layers

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Chinese Physics Letters 2008年第1期25卷 137-140页

作者： munazza Zulfiqar Ali Tariq Abdullah Centre of Excellence in Solid State Physics Quaid-i-Azam Campus Punjab University Lahore 54590 Pakistan

We investigate the effects of introducing a defect layer negative material layers on the transmission properties in a one-dimensional photonic crystal containing single The width of the defect layer is taken to be the same or smaller than the period of the structure. Different cases of the defect layer being linear or nonlinear and double positive or double negative are discussed. It is found that only a nonlinear double negative layer gives rises to a localized mode within the zero-Φeff gap in this kind of structure. It is also shown that the important characteristics of the nonlinear defect mode such as its frequency, its FWHM and the threshold of the associated bistability can be controlled by changing the widths of the defect layer and the host layers.

关键词： pulsars x-ray spectra relativity and gravitation redshift

Properties of single and multiple defect modes in one-dimensional photonic crystals containing left-handed metamaterials

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Chinese Optics Letters 2012年第7期10卷 69-72页

作者： munazza Zulfiqar Ali Physics Department Punjab University

Wave propagation is studied in structures consisting of alternate left- and right-handed layers. Bragg gap and zero-n gap appear in different frequency regions of the structure. The periodicity of the structure is broken by simply reversing the order of the layers in one half of the structure, resulting in defect modes located inside the zero-n gap and Bragg gap. These modes can be made very narrow by adding more layers in the structure. The defect mode located inside the zero-n gap is sensitive to the symmetry of the structure and insensitive to the angle of incidence of the incoming radiation. Multiple modes are also generated inside the gaps by repeating the structural pattern. Thus, a simple structure can be used for single and multiple modes that are imDortant for different applications.

关键词： mode Properties of single and multiple defect modes in one-dimensional photonic crystals containing left-handed metamaterials left

Effective medium parameters for 1D photonic crystal containing single-negative material layers using the envelope function approach

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Chinese Optics Letters 2013年第4期11卷 1-3页

作者： munazza Zulf iqar Ali Physics Department Quaid-i-Azam Campus Punjab University

Nonlinear wave propagation in a 1D photonic crystal containing single-negative layers is investigated using the multiple-scale method. In this approach, the electric field is decomposed into a slowly varying envelope function and a fast Bloch-like function to obtain the analytic expressions of the effective parameters of an equivalent medium. The periodic structure has an equivalent left-handed medium for the envelope function. Gap soliton formation is discussed and compared with that associated with the Bragg gap.

关键词： 050.5298 Photonic crystals 060.4370 Nonlinear optics, fibers 070.7345 Wave propagation

An Effective Online Collaborative Training in Developing Listening Comprehension Skills

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Computer Systems Science & Engineering 2021年第8期38卷 131-140页

作者： Shakeel Ahmed munazza Ambreen Muneer Ahmad Abdulellah A.Alaboudi Roobaea Alroobaea NZ Jhanjhi Department of Secondary Instructors Education Faculty of EducationAllama Iqbal Open UniversityIslamabadPakistan Department of Information Systems Faculty of Computer Science&ITUniversiti Malaya50603 Kuala LumpurMalaysia College of Computer Science Shaqra UniversitySaudi Arabia Department of Computer Science College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia School of Computer Science and Engineering SCETaylor’s UniversitySubang Jaya47500Malaysia

The COVID-19 outbreak severely affected formal face-to-face classroom teaching and ***-based online education and training can be a useful measure during the *** the Pakistani educational context,the use of ICT-based online training is generally sporadic and often unavailable,especially for developing English-language instructors’listening comprehension *** major factors affecting availability include insufficient IT resources and infrastructure,a lack of proper online training for speech and listening,instructors with inadequate academic backgrounds,and an unfavorable environment for ICT-based training for listening *** study evaluated the effectiveness of ICT-based training for developing secondary-level English-language instructors’listening comprehension *** this end,collaborative online training was undertaken using random ***,60 private-school instructors in Chakwal District,Pakistan,were randomly selected to receive online-listening training sessions using English *** experimental group achieved significant scores in the posttest ***,there were substantial improvements in the participants’listening skills via online *** the unavailability of face-to-face learning during COVID-19,this study recommends using ICT-based online training to enhance listening comprehension *** policymakers should revise curricula based on online teaching methods and modules.

关键词： COVID-19 online training remote teaching computers in education listening comprehension English language

Characteristics of Ions Emitted from Laser-Induced Silver Plasma

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Plasma Science and Technology 2008年第4期10卷 450-454页

作者： M.S.RAFIQUE M.KHALEEQ-UR-RAHMAN Shakoor munazza K.A.BHATTI Department of Physics University of Engineering and TechnologyLahore-54890Pakistan

In this work, study of laser-induced ions is presented. The plasma was produced by focusing a Nd：YAG laser, with a wavelength of 1064 nm, a pulsed width of 9-14 ns, a power of 1.1 MW and energy of 10 mJ, on silver target in vacuum （10-3 Torr= 1.3332 Pa）. The characteristics of ion streams were investigated by CR-39 detectors located at angles of 0°, 30°, 60° and 90° with respect to normal of the target. The distance between the silver target and each detector was 11 cm. The energy of silver ions was found ranging from 1.5 eV to 1.06E4 eV. There was a high concentration of ions with low energy as compared to those with high energy, showing the energy distribution amongst the ions. The flux of ions was maximum in the axial direction which was decreasing with the angle increase with respect to normal of the target, and finally became minimum in the radial direction. Hence the silver ions have shown anisotropic behaviour.

关键词： Nd: YAG laser flux of ions anisotropic solid state nuclear track detector (SSNTD)

Global transmission diagrams for evanescent waves in a nonlinear hyperbolic metamaterial

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Chinese Optics Letters 2015年第9期13卷 1-5页

作者： munazza Zulfiqar Ali Ashfaq Ahmad Bhatti Qamar ul Haque Shahzad Mahmood Physics Department Punjab University Theoretical Physics Division PINSTECH

A theoretical model of a nonlinear hyperbolic metamaterial is presented in the form of a stack of subwavelength layers of linear plasmonic and nonlinear dielectric materials. A broad picture of the properties of evanescent waves （high-k modes） in this stack is investigated by plotting global transmission diagrams. The presence of nonlinearity strongly modifies these diagrams. The emergence and modification of nonlinear evanescent waves is observed. Some signatures of nonlinear phenomenon such as formation of orbits and trajectories around fixed points are also seen in our work.

关键词： Global transmission diagrams for evanescent waves in a nonlinear hyperbolic metamaterial

Physiological Evaluation of Wheat (<i>Triticum aestivum</i>L.) Genotypes at Pre-Anthesis Stage under Heat Stress Conditions

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American Journal of Plant Sciences 2021年第12期12卷 1780-1790页

作者： munazza Nazir Asghari Bano Faizan Ullah Samiullah Khan Naeem Khan Department of Botany University of Azad Jammu & Kashmir Muzaffarabad Azad Kashmir Pakistan Department of Biosciences Quaid Avenue University of Wah Wah Cantt Pakistan Department of Botany University of Science and Technology Bannu Pakistan Department of Agronomy University of Haripur Haripur Pakistan Department of Agronomy University of Florida Gainesville FL USA

Experiments were conducted to analyze effects of high temperature stress on wheat at pre-anthesis growth stage. Twenty four wheat genotypes exposed to a sub optimal temperature (>35°C) which showed altered physiological, biochemical and agronomic characteristics. Accumulation of proline, presence of new protein bands and higher antioxidant enzyme activity in leaves of G.7 and G.17 reflects their better adaptive response under heat stress conditions. G.17 and G.19 showed least reduction in number of spikelets per spike, biological yield and 100 grain weight. It was inferred that the genotypes G.7, G.17 and G.19 exhibited greater heat tolerance and could be recommended for cultivation under heat stress conditions.

关键词： Heat Stress Tolerance Mechanisms Protein Profiling Osmolytes

Textile Environmental Conditioning: Effect of Relative Humidity Variation on the Tensile Properties of Different Fabrics

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Journal of Analytical Sciences, Methods and Instrumentation 2012年第2期2卷 92-97页

作者： Mansoor Iqbal munazza Sohail Aleem Ahmed Kamran Ahmed Arsheen Moiz Khalil Ahmed Applied Chemistry Research Centre PCSIR Laboratories Complex Karachi Pakistan

With the aim that to confirm the need for humidity control in the environment in which textile sample are visually and instrumentally analyzed, three different pre-conditioned fabrics sample of cotton, polyester and silk were treated at a fix temperature of 21?C. The relative humidity adjusted to four levels: 55%, 65%, 75% and 85% RH for a conditioning time of 24 hours as specified in ASTM D-1776-98. It has been observed that as the relative humidity increase from 55% to 85% cotton increase its tensile strength, silk losses its strength and there was no significant change observed in the tensile strength of polyester fabric.

关键词： Tensile Properties Relative Humidity Temperature Fiber Silk Polyester Cotton

Comparison between Pigment Printing Systems with Acrylate and Butadiene Based Binders

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Journal of Analytical Sciences, Methods and Instrumentation 2012年第2期2卷 87-91页

作者： Mansoor Iqbal Javaid Mughal munazza Sohail Arsheen Moiz Kamran Ahmed Khalil Ahmed Applied Chemistry Research Centre PCSIR Laboratories Complex Karachi Pakista Applied Chemistry Research Centre PCSIR Laboratories Complex Karachi Pakistan

Pigment printing was carried out on lab scale by simple screen-printing techniques. By the application of acrylate and butadiene based binder, the crocking fastness, formaldehyde release and PVC migration of fabric printed with Imparon red KB pigment was evaluated. The effect of curing time on K/S values was also investigated. It has been found that butadiene based binder shows good performance in terms of crocking fastness, formaldehyde release and PVC migra-tion. It has also been observed that by increasing the binder concentration, the release of formaldehyde decreased and by increasing the curing time, the K/S values of printed fabric were decreased.

关键词： Printing Pigment Binder Acrylate Butadiene