A new method for estimating human error probabilities: AHP–SLIM

Accidents in industrial settings are mainly a result of human errors (HEs); relevant fields that consider HEs have recently increased in number. For this reason, numerous methods to quantitatively estimate what is known as the HE probability (HEP) have been developed. However, it is difficult to obtain empirical data, which forces a heavy reliance on the judgment of experts in the field. During the process of judgments by experts, subjectivity plays an important role, causing difficulties in assuring consistency. To overcome this problem and to obtain a more accurate estimation, this study suggests a new and simple method. This method is referred to as AHP–SLIM, a type of HEP estimation using an analytic hierarchy process (AHP), which quantifies the subjective judgment and confirms the consistency of collected data. This new method also uses the process of expert judgment within the success likelihood index method (SLIM).     

Experimental and analytical study on the spray characteristics of dimethyl ether (DME) and diesel fuels within a common-rail injection system in a diesel engine

This paper investigates the effect of injection parameters on the characteristics of dimethyl ether (DME) as an alternative fuel in a diesel engine with experimental and analytical models based on empirical equations. In order to study macroscopic and microscopic characteristics of DME fuel, this work focuses on the atomization characteristics of DME and compares experimental and predicted results for spray development obtained by empirical models for diesel and DME fuel. Detailed comparisons of spray tip penetration from three different empirical correlations and from visualization experiments of diesel and DME fuels were conducted under various fuel injection conditions. In comparison with the results of different empirical equations for measured spray tip penetration, the experimental results of this study provide good agreement with the calculation results based on empirical equations, except during the earliest stage of the injected spray sequence. The results of atomization characteristics indicate that DME showed better spray characteristics than conventional diesel fuel. Also, the fuel injection delay and maximum injection rate of DME fuel are shorter and lower than those of diesel fuel at the same injection conditions, respectively.     

Structure-property relationships of hydroxy-terminated polyether based polyurethane network

In the present work, the effect of crosslink density on HTPE networks has been studied in swelling, thermal and mechanical properties. The solubility parameters of HTPE PUs were obtained by swelling test. They depended on the molar ratio of N-100 and IPDI and equivalent ratio. It was decreased as the content of N-100 was lowered. The thermal characteristics of the network polymer were examined by DSC results. Thermal behavior of HTPE PU network depended on by dangling chain and chain folding in the series using N-100, with NCO/OH ratio as 1.0, 0.8, 0.6. However, when we performed experiment with IPDI and N-100, with NCO/OH ratio as 1.0, the thermal properties depended on M_c. Moreover, using IPDI with N-100 showed enhanced volume specific energy than using only N-100 in tensile test due to strain induced crystallization.     

Melting treatment of waste asbestos using mixture of hydrogen and oxygen produced from water electrolysis

In this study, we melted four types of waste asbestos containing material such as spread asbestos, plasterboard asbestos, slate asbestos and asbestos 99 wt%, in a melting furnace at 1,450–1,550 that uses a mixture of hydrogen and oxygen (Brown’s gas) as a fuel. More volatile components (CaO, K₂O) are enriched in spread asbestos, plasterboard asbestos, and slate asbestos, while less volatile compounds (SiO₂, Fe₂O₃, MgO) remain in asbestos 99%. Through basicity of raw materials, spread asbestos, plasterboard asbestos, and slate asbestos were found to have more alkalinity, and asbestos 99% was found more acidic. SEM and EDX results revealed that all raw materials had various kinds of asbestos fiber. Spread asbestos, plasterboard asbestos, and slate asbestos were considered as tremolite asbestos, whereas asbestos 99% was considered as chrysotile asbestos. It was further confirmed by SEM and XRD studies that all waste materials contained some crystalline structures which transformed into amorphous glassy structure on melting. Also, in case of added glass cullet during the melting of spread asbestos, it transformed the raw material into a perfect vitrified product having more glassy surface and amorphous in nature     

Itraconazole–Laponite: Kinetics and mechanism of drug release

A clay-drug nanohybrid was prepared by interfacial boundary ion exchange reaction, from which the release mechanism of a poorly water soluble drug, itraconazole, was studied systematically. The effect of cation types on drug release was investigated on the basis of a UPS 25 guide line and the effect of Laponite dissolution was also studied at pH = 1.2. To describe the release patterns, mathematical modeling was preformed using first-order, Elovich, parabolic diffusion, and power function equations.     

Effect of blend composition on the morphology development of electrospun fibres based on PAN/PMMA blends

BACKGROUND: The aim of the work presented was to determine the morphology development and relevant change in fibre diameter of a binary polymer blend system during an electrospinning process. The size of the fibre diameter is one of the important factors determining the general properties of non‐woven mats formed from electrospun fibres. RESULTS: The morphology and diameter of electrospun polyacrylonitrile (PAN)/poly(methyl methacrylate) (PMMA) blends were investigated as a function of blend ratio using scanning electron microscopy. The diameter of the electrospun PAN/PMMA fibres decreased with increasing PMMA content up to 50 wt%, and then increased again with further increase of PMMA. After thermal treatment, the fibres shrank, and an irregularly shaped morphology was observed. CONCLUSION: The electrospinning of incompatible PAN/PMMA blends leads to a microphase‐separation morphology of fibres. A phase inversion occurs at a PMMA content of between 50 and 75 wt%. Due to the phase inversion, the fibre diameter shows a minimum value at the relevant composition. Copyright © 2008 Society of Chemical Industry     

The synthesis of crown ether-appended dichlorofluoresceins and their selective Cu2+ chemosensing

Dichlorofluorescein derivatives with two aza-crown ether binding units were prepared by the Mannich reaction and their chemosensing behaviors toward transition metal ions were investigated. An 18-crown-6 ether derivative exhibited pronounced Cu²⁺-selective fluorescence signaling, with selectivity over other common physiologically important alkali, alkaline earth and transition metal ions. The compound also displayed 1:1 complex formation with Cu²⁺ ion, with a detection limit of 2.9 × 10^?6 M in an aqueous 50% DMSO solution at pH 7, showing that it may offer potential as a chemosensor for the detection of submillimolar Cu²⁺ ions in physiological environments. A 15-Crown-5 ether analogue also revealed selective Cu²⁺ signaling, although with somewhat diminished selectivity compared with its 18-crown-6 counterpart.     

Blue light-emitting diodes from 2-(10-naphthylanthracene)-spiro[fluorene-7,9′-benzofluorene] host material

A novel, spiro-type host material 2-(10-naphthylanthracene)-spiro[fluorene-7,9′-benzofluorene] was prepared by reacting 2-bromo-spiro[fluorene-7,9′-benzofluorene] with 9-(2-naphthylanthracene)-10-boronic acid via the Suzuki reaction. 2-4′-(Phenyl-4-vinylbenzeneamine)phenyl-spiro[fluorene-7,9′-benzofluorene], 4-[2-naphthyl-4′(phenyl-4-vinylbenzeneamine)]phenyl and diphenyl-[4-(2-[1,1;4,1]terphenyl-4-yl-vinyl)-phenyl]-amine were used as dopant materials. Devices with the configuration of ITO/N,N′-bis[4-(di-m-tolylamino)phenyl]-N,N′-diphenylbiphenyl-4,4′-diamine)/bis[N-(1-naphthyl)-N-phenyl]benzidine/2-(10-naphthylanthracene)-spiro[fluorene-7,9-benzofluorene]:5% dopant/aluminum tris(8-hydroxyquinoline)/Al-LiF showed a maximum power efficiency of 3.7 cd/A at 17.93 mA/cm² and a maximum luminance of 5018 cd/m² at 10 V with a turn-on voltage of 4.5 V.