Comparative Study on the Properties of Galvanically Deposited Nano- and Microcrystalline Thin Films of PbSe

Thin films of PbSe having both nano- and microstructures have been deposited on transparent conducting oxide (TCO)-coated glass substrates electrochemically, from an aqueous solution of Pb(OAc)₂, ethylenediamine tetraacetic acid (EDTA), and SeO₂. A Pb strip acted as the sacrificial anode, while the TCO glass was the cathode. No external bias was applied. The formation of PbSe was pH sensitive, and pH ~3 was found to be optimum for film deposition. Films grown at room temperature (25°C) were nanocrystalline (~25 nm), while those deposited at 80°C were microcrystalline (~150 nm). Films were characterized by x-ray diffraction studies, field-emission scanning electron microscope image analysis, infrared spectral analysis, and by both alternating-current (a.c.) and direct-current (d.c.) electrical measurements. A blue-shift was observed for the nanocrystalline films. Film resistivity and junction properties were obtained from electrical measurements.     

ERP and SCM systems integration: The case of a valve manufacturer in China

Many modern organizations integrate enterprise resource planning (ERP) and supply chain management (SCM) systems, as they work in a complementary fashion. This often results in technical and organizational challenges. Neway, a Chinese organization, recently went through this complex process. This required efficient procurement and management of hardware, software, and human resources for successful completion. The integrated system was found to improve operations, foster a paperless environment, and provide efficient inventory tracking and picking. It also had several tangible benefits, including reduced lead time and improved inventory accuracy. ERP and SCM systems integration is still a novel concept for a Chinese manufacturing organization. Our case study details the organization's experience, identifies challenges that were faced, and describes solutions adopted to overcome them.     

Microstructure and growth of ZnTe films

The microstructure and growth of ZnTe films deposited onto glass and freshly cleaved NaCl substrates are carefully studied by a TEM. Effect of different stimulator on the grain growth is also described.     

The differential induction machine: Theory and performance

This paper presents the theory and performance of a differential induction machine, which is a special type of induction machine having two shafts projected from the two ends of a single stator. Application of a differential load on the two shafts cause them to run at different speed as a motor, which permits true differential movement and thus can meet the requirements of a differential drive in an electric vehicle. The machine is also capable of regeneration in the differential mode. This paper presents the construction of the above machine and performance of the same based on experimental results from a laboratory prototype. The equivalent circuit of the motor has been presented and verified experimentally.     

A simplification of a real‐time verification problem

We revisit the problem of real‐time verification with dense‐time dynamics using timeout and calendar‐based models and simplify this to a finite state verification problem. We introduce a specification formalism for these models and capture their behaviour in terms of semantics of timed transition systems. We discuss a technique, which reduces the problem of verification of qualitative temporal properties on infinite state space of a large fragment of these timeout and calender‐based transition systems into that on clock‐less finite state models through a two‐step process comprising of digitization and finitary reduction. This technique enables us to verify safety invariants for real‐time systems using finite state model checking avoiding the complexity of infinite state (bounded) model checking and scale up models without applying techniques from induction‐based proof methodology. In the same manner, we verify timeliness properties. Moreover, we can verify liveness for real‐time systems, which are not possible by using induction with infinite state model checkers. Copyright © 2016 John Wiley & Sons, Ltd.     

Synthesis of flexible polymeric shielding materials for soft gamma rays: Physicomechanical and attenuation characteristics of radiation crosslinked polydimethylsiloxane/Bi2O3 composites

Flexible lead‐free high energy radiation shielding material was developed through internal compounding. Polymer‐filler interaction, crosslinking density, specific gravity, physicomechanical characteristics, percentage attenuation, and thermal stability of the crosslinked composites were estimated. It was found that even at very high filler loading composites can be crosslinked; however, the crosslinking density was composition dependent and was highest in 10–50 wt% loading range at 100 kGy and 200 kGy. The Nielsen model was applied to understand the micromechanics of the system. Attenuation of gamma radiation from Am241 was not affected by the crosslinking density. Thermal stability of the composites was found to be significantly affected with bismuth oxide loading. POLYM. COMPOS., 37:756–762, 2016. © 2014 Society of Plastics Engineers     

Distributed fault-tolerant topology control in wireless multi-hop networks

In wireless multi-hop and ad-hoc networks, minimizing power consumption and at the same time maintaining desired properties of the network topology is of prime importance. In this work, we present a distributed algorithm for assigning minimum possible power to all the nodes in a static wireless network such that the resultant network topology is k-connected. In this algorithm, a node collects the location and maximum power information from all nodes in its vicinity, and then adjusts the power of these nodes in such a way that it can reach all of them through k optimal vertex-disjoint paths. The algorithm ensures k-connectivity in the final topology provided the topology induced when all nodes transmit with their maximum power is k-connected. We extend our topology control algorithm from static networks to networks having mobile nodes. We present proof of correctness for our algorithm for both static and mobile scenarios, and through extensive simulation we present its behavior.     

Traffic grooming,routing, and wavelength assignment in an optical WDM mesh networks based on clique partitioning

In wavelength routed optical networks, the number of wavelength channels is limited due to several constraints and each wavelength as well as each lightpath support traffic in the Gbps range. On the other hand, the traffic requested by an individual connection is still in the Mbps range. Therefore, to utilize the network resources (such as bandwidth and transceivers) effectively, several low-speed traffic streams have to be efficiently groomed or multiplexed into one or more high-speed lightpaths. The grooming problem of a static demand is considered as an optimization problem. In this work, we have investigated the traffic grooming problem with the objective of maximizing the network throughput for wavelength-routed mesh networks and map this problem to the clique partitioning problem. We have proposed an algorithm to handle general multi-hop static traffic grooming based on the clique partitioning concept. The efficiency of our approach has been established through extensive simulation on different sets of traffic demands with different bandwidth granularities for different network topologies and compared the approach with existing algorithms.     

Synthesis of cross-linked graft copolymer from [2-(methacryloyloxy)ethyl] trimethylammonium chloride and poly(vinyl alcohol) for removing chromium(VI) from aqueous solution

A novel graft copolymer of [2-(methacryloyloxy)ethyl] trimethylammonium chloride onto poly(vinyl alcohol) has been synthesized and it is cross-linked by glutaraldehyde for the investigation of its efficiency in removing Cr(VI) from aqueous solution. The chemical nature of the ion-exchange resin has been elucidated with the help of chemical test, Fourier transform infrared, thermo gravimetric analysis and DTA. Particle size, surface area, ion-exchange capacity, optimum pH, reaction time and temperature for Cr(VI) extraction were determined. Chromium(VI) adsorption kinetics, isotherm and thermodynamics have been studied. A plausible mechanism for chromium ion-exchange has been suggested.     

Ru(II)–CO complexes of thioarylazoimidazoles: Syntheses,structures, spectroscopy and DFT calculation

The complexes, cis-(CO)-trans-(Cl)-[Ru(SRaaiNR)(CO)₂Cl₂] (2) and trans-(Cl)-[Ru(SRaaiNR)(CO)Cl₂] (3) (SRaaiNR = 1-alkyl-2-{(o-thioalkyl)phenylazo}imidazoles; R = Me (1a) and Et (1b)) have been synthesized and characterized. The structural confirmation is achieved by single crystal X-ray structure determinations. The complexes show Ru(III)/Ru(II) couple and ligand reductions. Electronic structure and spectral properties of the complexes have been explained with the DFT and TDDFT calculation.