Effect of solvent on the characteristics of nanostructured composites of poly (1-naphthylamine) with poly (vinyl alcohol)

Ufana Riaz,Sharif Ahmad,S.M. Ashraf 한국물리학회 2009 Current Applied Physics Vol.9 No.3

Efficient utilization of inherently conducting polymers in nano technological applications faces the challenge to assemble them into highly ordered structures which may yield novel properties. The present study reports for the first time the synthesis and characterization of nanostructured poly (1-naphthylamine) (PNA) dispersed polyvinyl alcohol (PVA) composites. The composites were prepared by loading PNA from 2 wt% to 10 wt% in PVA in aqueous as well as nonaqueous media. The composites were characterized by UV–visible spectroscopy, TEM, stress–strain studies, electrical conductivity measurements and moisture absorption studies under controlled humidity. A discrete but uniform distribution of nanoparticles was obtained in PNA/PVA composites synthesized in water having particle size between 5 and 30 nm. A self assembled network of nanostructured PNA particles was obtained in case of PNA/PVA composites synthesized in N-methylpyrolidone (NMP) with particle sizes between 10 and 65 nm. The variation in the nanostructured morphology of PNA particles in PVA matrix in the two cases resulted from the pronounced interaction of PVA with NMP through hydrogen bonding. This leads to the formation of a homogeneous matrix that facilitates the formation of a self assembled network of PNA nano particles. In case of PNA/PVA composites synthesized in water, lower affinity of PVA towards water was responsible for a discrete, agglomerate free distribution of PNA particles. We have found that the PNA/PVA nano composite synthesized in water exhibited good mechanical properties and electrical conductivity (8.1 × 10-1 S/cm) as well as lowest moisture absorption (4 wt%) which holds potential for use in semiconductor and biomedical devices. Efficient utilization of inherently conducting polymers in nano technological applications faces the challenge to assemble them into highly ordered structures which may yield novel properties. The present study reports for the first time the synthesis and characterization of nanostructured poly (1-naphthylamine) (PNA) dispersed polyvinyl alcohol (PVA) composites. The composites were prepared by loading PNA from 2 wt% to 10 wt% in PVA in aqueous as well as nonaqueous media. The composites were characterized by UV–visible spectroscopy, TEM, stress–strain studies, electrical conductivity measurements and moisture absorption studies under controlled humidity. A discrete but uniform distribution of nanoparticles was obtained in PNA/PVA composites synthesized in water having particle size between 5 and 30 nm. A self assembled network of nanostructured PNA particles was obtained in case of PNA/PVA composites synthesized in N-methylpyrolidone (NMP) with particle sizes between 10 and 65 nm. The variation in the nanostructured morphology of PNA particles in PVA matrix in the two cases resulted from the pronounced interaction of PVA with NMP through hydrogen bonding. This leads to the formation of a homogeneous matrix that facilitates the formation of a self assembled network of PNA nano particles. In case of PNA/PVA composites synthesized in water, lower affinity of PVA towards water was responsible for a discrete, agglomerate free distribution of PNA particles. We have found that the PNA/PVA nano composite synthesized in water exhibited good mechanical properties and electrical conductivity (8.1 × 10-1 S/cm) as well as lowest moisture absorption (4 wt%) which holds potential for use in semiconductor and biomedical devices.

Bringing Handhelds to the Grid Resourcefully: A Surrogate Middleware Approach

Riaz, M.,Kiani, S. L.,Shehzad, A.,Lee, S. SPRINGER-VERLAG 2005 ICHIT 2012 Vol.3481 No.-

Selection and Optimization of Silane Coupling Agents to Develop Durable Functional Cotton Fabrics Using TiO2 Nanoparticles

S. Riaz,M. Ashraf,T. Hussain,M. T. Hussain,A. Younus,M. Raza,A. Nosheen 한국섬유공학회 2021 Fibers and polymers Vol.22 No.1

In recent years there is progressive research conducted on modification of textile and nanoparticles for long-lastingperformances without compromising the sensorial and non-sensorial comfort. The appropriate finishing treatment of textile isof great concern to impart comfort along with durable multifunctional characters. The main objective of this study was toachieve the durable functionality without compromising the comfort and physical properties of cotton fabric. TiO2nanoparticles have been modified with two different silane coupling agents such as (3-Glycidoxypropyl)trimethoxysilane(GPTS) and 1,2-Bis(triethoxysilyl)ethane (BTSE) using different concentrations. The modified nanoparticles werecharacterized using Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR),thermogravimetric analysis (TGA) to confirm the modification and fixing of chemicals at the surface. Modified nanoparticleswere applied on textile by pad-dry-cure method. The treated cotton fabrics were washed to confirm the adhesion ofnanoparticles after several washing cycles. The durable ultraviolet (UV) blocking capabilities were analyzed before and afterwashing. Then, comfort properties were evaluated and compared to made selection of best silane coupling agent havingminimum effect on inherent properties of cotton textiles.

A Low Cost Electro-Oculogram (EOG) Controlled Assistive Wheel Chair

Raheel Riaz,S.Hammad Akhter,Aisha Masood,Ana Zulfiqar,Khoula Abid,Kiran Akhter,S. M. Omair,Zia Mohyud-din 한국재활복지공학회 2016 한국재활복지공학회 학술대회논문집 Vol.2016 No.11

Increased Paralysis or physical disability cases are one of the greatest problems of this technologically developing world. It destroys the life and self-esteem of the survivor and they become dependable on others to fulfill their mobility needs. Many works has been done to aid their disability and to give them independent mobility. Several sophisticated methods have been designed to generate such assistive devices to help the disable peoples. Some of such devices include the use of cameras to produce movement based on eye gaze, another such method consists of the use of high-end computer systems that can process the data efficiently but these are very expensive and less portable. This research introduce a cost effective method to generate assistive device to guide and control the wheel chair for disable people, it involves the non-sophisticated technology based on analog filters, amplifiers and Electrooculography (measure of the Corneo-retinal standing potential that exists between the front and the back of the human eye.). Eye movement directions are used to guide and control the wheel chair.

Biochar soil amendment on alleviation of drought and salt stress in plants: a critical review

Ali, S.,Rizwan, M.,Qayyum, M. F.,Ok, Y. S.,Ibrahim, M.,Riaz, M.,Arif, M. S.,Hafeez, F.,Al-Wabel, M. I.,Shahzad, A. N. Springer Science + Business Media 2017 Environmental Science and Pollution Research Vol.24 No.14

<P>Drought and salt stress negatively affect soil fertility and plant growth. Application of biochar, carbon-rich material developed from combustion of biomass under no or limited oxygen supply, ameliorates the negative effects of drought and salt stress on plants. The biochar application increased the plant growth, biomass, and yield under either drought and/or salt stress and also increased photosynthesis, nutrient uptake, and modified gas exchange characteristics in drought and salt-stressed plants. Under drought stress, biochar increased the water holding capacity of soil and improved the physical and biological properties of soils. Under salt stress, biochar decreased Na+ uptake, while increased K+ uptake by plants. Biochar-mediated increase in salt tolerance of plants is primarily associated with improvement in soil properties, thus increasing plant water status, reduction of Na+ uptake, increasing uptake of minerals, and regulation of stomatal conductance and phytohormones. This review highlights both the potential of biochar in alleviating drought and salt stress in plants and future prospect of the role of biochar under drought and salt stress in plants.</P>

Grid Access Middleware for Handheld Devices

Kiani, S. L.,Riaz, M.,Lee, S.,Jeon, T.,Kim, H. SPRINGER-VERLAG 2005 Lecture Notes in Computer Science Vol.3470 No.-

Structural and Morphological Properties of Zn1−xZrxO with Room-Temperature Ferromagnetism and Fabricated by Using the Co-Precipitation Technique

M. Hassan,R. Irfan,S. Riaz,S. Naseem,S. S. Hussain,G. Murtaza 한국물리학회 2017 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.70 No.5

In this study, ZnO was doped with various concentrations of zirconium (xZr = 0 - 5 mole%), by using the co-precipitation method so as to achieve successful formation of a single-phase diluted magnetic semiconductor. X-Ray diffraction results showed that the crystal structure of Zn1−xZrxO was that of hexagonal wurtzite. The structural properties showed no additional phases at low impurity contents (xZr < 3%); however, impurity peaks belonging to ZrO2 appeared at high impurity contents (xZr 3%). The calculated ZnO lattice constants ‘a’ and ‘c’ were found to be 3.256 °A and 5.203 °A, respectively, which are in close match to the values found in the literature. For undoped ZnO, the average calculated particle size was 75.35 nm, and calculated bond length was 1.98 °A. The residual strains and the secondary phases of ZrO2 were found to affect the lattice parameters and the bond lengths. The scanning electron microscopy images showed a porous structure with non-uniform surface morphology. However, a few nano-scale dendrite-type structures were also present, indicating the potential applications of Zr-doped ZnO in nano-devices. Vibrating sample magnetometry (VSM) was employed to measure the magnetic properties, and the measurements showed undoped ZnO to be diamagnetic; however, doping with Zr induced a small ferromagnetic character at small magnetic fields. On the otherhand, a paramagnetic behavior was evident at higher magnetic fields. The magnetization at 1T was observed to degrade with increasing Zr content in the ZnO host lattice, which was due to the residual strains and the secondary phases.

2006 WHOLE EARTH TELESCOPE OBSERVATIONS OF GD358: A NEW LOOK AT THE PROTOTYPE DBV

Provencal, J. L.,Montgomery, M. H.,Kanaan, A.,Shipman, H. L.,Childers, D.,Baran, A.,Kepler, S. O.,Reed, M.,Zhou, A.,Eggen, J.,Watson, T. K.,Winget, D. E.,Thompson, S. E.,Riaz, B.,Nitta, A.,Kleinman, S IOP Publishing 2009 The Astrophysical journal Vol.693 No.1

Ethernet‑Based Fault Diagnosis and Control in Smart Grid: A Stochastic Analysis via Markovian Model Checking

Riaz Uddin,Ali S. Alghamdi,Muhammad Hammad Uddin,Ahmed Bilal Awan,Syed Atif Naseem 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.6

The fault diagnosis and control through fault detection, isolation and supply restoration (FDIR) technique is the part of a commonly used distribution management system application in smart grid. When the fault occurs, it becomes essential to detect and isolate the faulty section of the distribution network at once and then restore back to its running condition through tie switches. The communication between IEDs is done through diferent communication mediums such as Ethernet, wireless, power line communication etc. Therefore, formal analysis of the FDIR mechanism is required with communication network (ideally Ethernet), which helps us to predict the behavior of FDIR response upon the occurrence of fault in terms of various important probabilities, reliability study and efciency (showing the system will work properly). In this regard, for the above said analyses, this article discusses (a) the development of the Markovian model of FDIR for distribution network of smart grid considering Tianjin Electric Power Network as case study with intelligent electronic devices (IEDs) using ideal communication medium (Ethernet); (b) utilized probabilistic model checker (PRISM tool) to predict the probabilities; (c) perform the reliability analyses and (d) study the efciency of FDIR behavior for future grid using logical properties. The detailed analysis and prediction (done for the fault occurrence scenario) mainly focus in determining the (1) the probability of switching failures of FDIR in smart grid; (2) the probability of isolating the defective switch from the system within limited time and (3) the probability of restoring the system automatically within the minimum possible interval.

Effects of External Magnetic Field on non-Newtonian Two Phase Fluid in an Annulus with Peristaltic Pumping

A. Riaz,A. Zeeshan,S. Ahmad,A. Razaq,M. Zubair 한국자기학회 2019 Journal of Magnetics Vol.24 No.1

This paper comprises the exact solutions of Non-Newtonian multiphase fluid through peristaltic pumping characteristics in an annulus having complaint walls and applied magnetic field. The mechanics of the geometry are defined cylindrical due to its large number of utilizations in medicine and biological apparatus. The external cylinder is having sinusoidal waves travelling along its walls. The problem is simplified by some suitable and valid approximations. The authors have obtained the accurate solutions of the velocities of two phases. The effects of appertaining parameters have been displayed through graphs of velocity for v and particulate phases and the behavior of curves are manipulated accordingly. It is concluded that applied magnetic field decreases the velocity of both the fluid and the particles flow.