Clean low-temperature in situ synthesis of durable silver nanoparticles along with aminolysis of polyester fabric using dopamine hydrochloride

Clean Technologies and Environmental Policy - In this study, aminolysis of polyester fabric was carried out along with in situ synthesis of silver nanoparticles in a single-step processing at room...     

Vibrational investigation of the spinning bi-dimensional functionally graded (2-FGM) micro plate subjected to thermal load in thermal environment

Microsystem Technologies - This article presented a numerical method for discovering the free vibration of a spinning bi-dimensional functionally graded materials (FGM) micro circular plate exposed...     

Identifying the time of step change in binary profiles

Control charts are intended to aid quality practitioners in monitoring whether a change has occurred in a process. When a control chart indicates an out-of-control signal, it means that the process has changed. However, control chart signals do not indicate the real time of process changes; so estimators are applied to indicate the time when a change in the process takes place, which is referred to as the change point. This paper provides a maximum likelihood estimator to identify the real time of a step change in phase II monitoring of binary profiles, in which the quality of a process is characterized by a logistic regression between the response and predictor variables. Simulation studies are provided to evaluate the effectiveness of the change point estimator.     

A modern congestion pricing policy for urban traffic: subsidy plus toll

Railway Engineering Science - Congestion pricing is seen as an effective policy to address traffic congestion. In such policies where money, people and authorities are involved, the success...     

Numerical simulation and optimization of steam-assisted gravity drainage with temperature,rate, and well distance control using an efficient hybrid optimization technique

Steam-assisted gravity drainage (SAGD) is a thermal enhanced oil recovery technique through drilling of two horizontal wells. Effects of steam injection temperature, well rates, and their distance on oil recovery were analyzed and optimized. Steam temperature and well distances remarkably affect SAGD performance. Four metaheuristic algorithms (particle swarm optimization (PSO), imperialist competitive algorithm, cultural algorithm, and Bees algorithm) and pattern search optimization algorithm (PSA) are used for optimization. PSO performs better than other metaheuristics and PSA is the fastest one, while it is probable to be trapped in local optimums. Hybrid PSO-PS is proposed that starts with PSO and proceeds with PSA, and tested in an SAGD project and showed excellence over other techniques.     

Wear and Failure Analysis of Semi-Autogenous Grinding Mill Liners

Journal of Failure Analysis and Prevention - The wear and failure analysis of shell liners of a grinding mill is investigated. Metallurgical and tribological studies were conducted on the worn...     

Photoluminescence emission of nanoporous anodic aluminum oxide films prepared in phosphoric acid

The photoluminescence emission of nanoporous anodic aluminum oxide films formed in phosphoric acid is studied in order to explore their defect-based subband electronic structure. Different excitation wavelengths are used to identify most of the details of the subband states. The films are produced under different anodizing conditions to optimize their emission in the visible range. Scanning electron microscopy investigations confirm pore formation in the produced layers. Gaussian analysis of the emission data indicates that subband states change with anodizing parameters, and various point defects can be formed both in the bulk and on the surface of these nanoporous layers during anodizing.     

WO3 nano-ribbons: their phase transformation from tungstite (WO3·H2O) to tungsten oxide (WO3)

Tungsten oxide (WO₃) nano-ribbons (NRs) were obtained by annealing tungstite (WO₃·H₂O) NRs. The latter was synthesized below room temperature using a simple, environmentally benign, and low cost aging treatment of precursors made by adding hydrochloric acid to diluted sodium tungstate solutions (Na₂WO₄·2H₂O). WO₃ generates significant interests and is being used in a growing variety of applications. It is therefore important to identify suitable methods of production and better understand its properties. The phase transformation was observed to be initiated between 200 and 300 ^°C, and the crystallographic structure of the NRs changed from orthorhombic WO₃·H₂O to monoclinic WO₃. It was rigorously studied by annealing a series of samples ex situ in ambient air up to 800 ^°C and characterizing them afterward. A temperature-dependent Raman spectroscopy study was performed on tungstite NRs between minus 180 and 700 ^°C. Also, in situ heating experiments in the transmission electron microscope allowed for the direct observation of the phase transformation. Powder X-ray diffraction, electron diffraction, electron energy-loss spectroscopy, and X-ray photoelectron spectroscopy were employed to characterize precisely this transformation.