University of Wah

About: University of Wah is a education organization based out in Rawalpindi, Pakistan. It is known for research contribution in the topics: Per capita income & Rhizobacteria. The organization has 258 authors who have published 466 publications receiving 4719 citations.

Synthesis of stannic(IV) complexes: Their structural elucidation in solid and solution state and antimicrobial activity

Abstract: A series of organotin(IV) thiocarboxylates have been synthesized with the general formula R2SnL2 and R3SnL (R = Ph2(I), Me3(II), n-Bu3(III), Ph3(IV), Cy3(V), Me2(VI), n-Bu2(VII), and L = piperidine-1-thiocarboxylic acid) in anhydrous toluene under the reflux conditions. The complexes were characterized by microanalysis, IR, 1H and 13C NMR, mass spectrometry, and XRD. NMR data revealed that thiocarboxylic acid acts as bidentate, and complexes exhibit the four-coordinated geometry in solution state. In solid state, diorganotin complexes exhibit the hexa-coordinated geometry whereas the triorganotin(IV) compounds show the five-coordinated geometry. These complexes were also tested for their antimicrobial activity along with the ligand against different animals, plant pathogens, and Artemia salina. All complexes with few exceptions show high activity as compared to the ligand. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:664–674, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20380

Automatic rule installation in case of policy change in software defined networks

Abstract: Software Defined Networking (SDN) has emerged recently as a new network architecture. It implements both control and management planes at centralized controller and data plane at forwarding devices. Therefore, SDN helps to simplify network management and improves network programmability. Changes in network policies occur frequently by making modifications at controller. However, in existing approaches, the rules installed at switches before policy change at controller are not modified. This can cause violation of network policy by packets. To address this problem, this paper presents a new approach that stores the rules generated at controller. After detecting the change in policy, the proposed approach finds the rules that will be affected by policy change by examining stored rules at controller. Then the affected rules are removed from the forwarding devices. Simulation results reveal that our proposed approach provides less packets violation ratio and normalized traffic overhead as compared to existing approach. Therefore, the proposed approach increases network performance and efficiency.

Designing of 5,10-Dihydroindolo [3,2-b] Indole (DINI) Based Donor Materials for Small Molecule Organic Solar Cells

Abstract: In this paper, four small molecules B1, B2, B3 and B4 based on donor–acceptor–donor–acceptor–donor (D-A-D-A-D) combination were designed by making structural modifications in R. The designed molecu...

Facile synthesis of hydrogel-nickel nanoparticle composites and their applications in adsorption and catalysis

Abstract: Abstract Homopolymer bulk hydrogel of methacrylic acid was synthesized through a new single-step facile rout and used as a template for the fabrication of nickel (Ni) nanoparticles and as adsorbent to remove methylene blue (MB) and Rhodamine-6G (Rh-6G) from water. The Ni nanoparticles containing composite hydrogel was applied as catalyst for the degradation of a nitro compound. The carboxylic groups acted as highly efficient adsorption sites and their high degree was responsible for the removal of huge amounts of MB and Rh-6G from water. The maximum adsorption capacity of poly (methacrylic acid) hydrogel was 685 mg g−1 for MB and 1571 mg g−1 for Rh-6G. The adsorption data of MB was best fitted with Langmuir adsorption isotherm while that of Rh-6G with Temkin adsorption isotherm. Catalytic property of prepared hydrogel integrated with Ni nanoparticles was evaluated by using it as a catalyst for the degradation of 4-nitrophenol (4-NP). The apparent rate constant (kapp) observed in this study for the reduction of 4-NP was as high as 0.038 min−1. It was found that this catalyst system can be used repetitively with a slight decrease in catalytic activity.