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The attention of all concerned is drawn to the need for guarding against the effects of poisonous fumes when using chemical fire extinguishers of the types usually carried in civil aeroplanes. One of the dangers to be guarded against is that at low concentrations the fumes may have no smell, or such smell as there is may not be unpleasant, and may not suggest that breathing the air is in any way dangerous. Exposure for half an hour or so to such fumes may nevertheless produce subsequent ill effects, though none may be noticed until some hours after the exposure has ceased.

This paper aims to synthesize benzothiazole-azo disperse dyes which can be applied not only for dyeing and alkaline reduction of polyester fabric in one bath, but also for dyeing and peroxide bleaching of cotton/polyester blend fabric in one bath.

The synthesized benzothiazole-azo disperse dyes were confirmed by proton nuclear magnetic resonance (1H-NMR) spectroscopy, mass spectroscopy (MS) and UV–visible spectrophotometry. The performance on resistance to alkaline treatment and peroxide bleaching was tested by measuring the color strength of polyester fabric dyed with the synthesized benzothiazole-azo disperse dyes under high-temperature and high-pressure conditions.

Increasing the electron-withdrawing ability of the substituents in the diazo component and the electron-donating ability of the substituents in the coupling component resulted in a significant bathochromic shift of the maximum absorption wavelength. Except that the disperse dyes synthesized from the coupling components containing the hydroxyethyl group were unstable in alkaline solution, all others exhibited high resistance to alkaline treatment and peroxide bleaching.

The synthesized benzothiazole-azo disperse dyes provide the opportunities to combine dyeing and alkaline reduction of polyester fabric into one bath, and combine dyeing and peroxide bleaching of cotton/polyester blend fabric into one bath.

The synthesized benzothiazole-azo disperse dyes help to establish short processes of polyester and polyester/cotton blend fabrics so as to reduce energy consumption and raise production efficiency.

The purpose of this paper is to investigate the propagation of plane waves in an isotropic elastic medium under the effect of rotation, magnetic field and temperature-dependent properties with two‐temperatures.

The problem has been solved analytically by using the normal mode analysis.

The numerical results are given and presented graphically when mechanical and thermal force are applied. Comparisons are made with the results predicted by the three-phase-lag (3PHL) model and dual-phase-lag model in the presence and absence of cases where the modulus of elasticity is independent of temperature.

In this work, the authors study the influence of rotation and magnetic field with two‐temperature on thermoelastic isotropic medium when the modulus of elasticity is taken as a linear function of reference temperature in the context of the 3PHL model. The numerical results for the field quantities are obtained and represented graphically.

The purpose of this paper is to evaluate the efficiency of modifying reactive azo dyes using pyrazolo[1,2‐a]pyrazole fused systems as the chromophoric moiety which could satisfy many and varied criteria drawn from economic, synthetic, physicochemical and fastness properties.

Six novel heterocyclic disazo reactive dyes were prepared, containing monofunctional sulphatoethylsulphone (SES) and hetero‐bifunctional monochlorotriazine (MCT)/SES reactive groups. Dyes intermediates based on 4‐arylazo‐1,5‐dioxopyrazolo[1,2‐a]pyrazole chromophoric moieties are initially synthesised and coupled with two different diazonium salts having the aforementioned reactive groups, thus yielding the new target reactive dyes. The synthesised dyes are applied to cotton, wool and silk fabrics under the typical exhaust dyeing conditions and their dyeing properties were investigated.

The results assessed for dyeing indicate high‐quality dyeing properties. However, the heterobifunctional MCT/SES dyes showed higher exhaustion and fixation values, colour yields and fastness properties than those of the monofunctional SES dyes.

The method developed provided a simple and practical procedure for producing fused pyrazolo[1,2‐a]pyrazole disazo chromophoric systems that afford valuable reactive dyes. In addition, the dyes intermediates based on 4‐arylazo‐1,5‐dioxopyrazolo[1,2‐a]pyrazole as well as their disazo counterparts could be applied as acid dyes to wool and silk.

The method for producing novel disazo reactive dyes could find numerous applications for affording a variety of reactive dyes with different binding linkages and structural reactivity. These could be valuable as reactive dyes with different colour shades.

This paper aims to describe the formulation of a displacement-based triangular membrane finite element with true drilling rotational degree of freedom (DOF).

The presented formulation incorporates the true drilling rotation provided by continuum mechanics into the displacement field by way of using the polynomial interpolation. Unlike the linked interpolation, that uses a geometric transformation between displacement and vertex rotations, in this work, the interpolation of the displacement field in terms of nodal drilling rotations is obtained following an unusual approach that does not imply any presumed geometric transformation.

New relationship linking the mid-side normal displacement to corner node drilling rotations is derived. The resulting new element with true drilling rotation is compatible and does not include any problem-dependent parameter that may influence the results. The spurious zero-energy mode is stabilized in a careful way that preserves the true drilling rotational degrees of freedom (DOFs).

Several works dealing with membrane elements with vertex rotational DOFs have been published with improved convergence rate, however, owing to the need for incorporating rotations in the finite element meshes involving solids, shells and beam elements, having finite elements with true drilling rotational DOFs is more appreciated.

In this paper, vendor selection and order allocation problem is considered for a buyer dealing in multiple products to be supplied by multiple vendors. Each product has an associated lead time with stochastic demand having stochastic capacity for each vendor across entire time period. Uncertainties related to costs which are further influenced by the periodically changing incremental quantity discounts offered by various vendors. The purpose of this paper is to find an optimal trade-off of vendor selection and order allocation in the presence of uncertainties involving multiple conflicting objectives such as cost minimization, service level/quality level maximization and delivery lead time minimization concurrently.

Vendor selection problem considered here has a multi-objective optimization design subject to a set of demand, capacity and quantity discount based constraints. These constraints as well as uncertainty related to lead time have been handled using chance constraint approach. The problem is titled as “integrated dynamic vendor selection problem (IDVSP).” The proposed multi-objective IDVSP is solved using both non-pre-emptive goal programming (GP) and weighted sum aggregate objective function (AOF) technique.

Findings indicate goal achievement for different objectives from both non-pre-emptive GP and AOF procedure. While the goals are satisfactorily achieved as per the target values for cost and lead time, quality/service level was somewhat compromised in order to find an appropriate trade off.

The research work is original as it integrates dynamic as well as stochastic (uncertain) nature of supply chain simultaneously coupled with the concept of incremental quantity discounts on lot sizes.

THE immediate impression of this year's Salon was that of a return to reality. Instead of the customary collection of fanciful mock‐ups posed precariously in artistic diving or climbing angles, the aircraft on show (with one exception) had all flown and, as if to emphasize this by contradiction, they were mainly exhibited in natural, almost pedestrian, attitudes. The number of aeroplanes shown was small and was indicative of post‐war conditions. However, the representation was much more satisfactory from the international viewpoint than was the Salon of 1946, the countries represented besides France being Czechoslovakia, Great Britain, Italy, the Netherlands, Switzerland, Turkey and the U.S.A.

To demonstrate corrosion inhibition capabilities of new cyclic nitrones, containing hydrophobic substituents.

A number of new cyclic nitrones were synthesized. Corrosion inhibition efficiencies of these organic inhibitors were determined by gravimetric and electrochemical methods, using carbon steel as the substrate metal and 1 M HCl at 60°C as the corrosive environment. Concentration of inhibitor was varied between 50 and 400 ppm.

All compounds exhibited excellent corrosion efficiencies that ranged between 90.0 and 98.3 percent in 1 M HCl at 60°C. Tafel tests corroborated these results.

The inhibitors were tested in acidic medium. It is unknown how these inhibitors will function in the presence of other ions that are typically present in natural corrosive environment.

All organic compounds presented in this work are new and this is the first time their corrosion inhibition characteristics have been evaluated.

Historically, a range of health and safety (H&S) challenges continue to be experienced. A two-day construction Industry 4.0 oriented H&S summit presented an opportunity to survey the delegates. The purpose of the study was to determine their perceptions, whether the presentations had an impact on their understanding and appreciation of the H&S challenges and the potential of Industry 4.0 technologies to improve H&S.

This paper reports on the findings emanating from a quantitative study that entailed the completion of a self-administered questionnaire survey conducted among delegates at the inception and closure of a two-day construction H&S summit.

The findings indicate that a range of H&S challenges are experienced in construction, Industry 4.0 technologies can contribute to addressing the H&S challenges and the presentations had an impact on their understanding and appreciation of the H&S challenges.

The findings are primarily based upon perceptions in terms of the potential of Industry 4.0 technologies to contribute to addressing the H&S challenges.

This study reports on findings from one of a limited number of Industry 4.0 studies conducted in construction in South Africa. The findings indicate the level of awareness with respect to Industry 4.0 and the likelihood of the implementation of such technologies, as initially practitioners are likely to act based upon perceptions.