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A considerable reduction of threshold limit values for ethylene glycol methyl and ethyl ethers and their acetates has been proposed by the ACGIH (American Conference of Governmental Industrial Hygienists). Interest in propylene glycol ethers, as potential replacements for the traditional monoethylene glycol ethers is steadily growing because of toxicity, labelling and industrial hygiene reasons. Propylene glycol ethers are compared to ethylene glycol ethers. Evaporation and solubility performances are discussed. Substitution possibilities for ethylene glycol ethers are elaborated for solvent and water borne coating systems.

This paper aims to examine the squeezing flow of hybrid nanofluid within the two parallel disks. The 50:50% water–ethylene glycol mixture is used as a base fluid to prepare Ag–Fe_3O_4 hybrid nanofluid. Entropy generation analysis is examined by using the second law of thermodynamics, and Darcy’s modal involves estimating the behavior of a porous medium. The influences of Viscous dissipation, Joule heating and thermal radiation in modeling are further exerted into concern.

For converting partial differential systems to ordinary systems, a transformation technique is used. For the validation part, the numerical solution is computed by embracing a fourth-order exactness program (bvp4c) and compared with the analytical solution added by the homotopy analysis method (HAM). Graphical decisions expose the values of miscellaneous-arising parameters on the velocity, temperature and local-Nusselt numbers.

Hybrid nanofluid gives significant enhancement in the rate of heat transfer compared with nanofluid. The outcomes indicate that the average Nusselt number and entropy generation are increasing functions of the magnetic field, porosity and Brinkman number. When the thermal radiation rises, the average Nusselt number diminishes and the entropy generation advances. Furthermore, combining silver and magnetite nanoparticles into the water–ethylene glycol base fluid significantly enhances entropy generation performance.

Entropy generation analysis of the magneto-hydrodynamics (MHD) fluid squeezed between two parallel disks by considering Joule heating, viscous dissipation and thermal radiation for different nanoparticles is addressed. Furthermore, an appropriate agreement is obtained in comparing the numerical results with previously published and analytical results.

Vinyl Products Ltd. (a wholly‐owned subsidiary of Unilever PLC) last month commissioned Europe's largest pressure polymerisation reactor for the manufacture of vinyl acetate‐ethylene and vinyl acetate‐vinyl chloride‐ethylene copolymer emulsions at its Warrington factory.

This paper aims to provide a sensor for fast, sensitive and selective ethylene (C₂H₄) concentration measurements.

The paper developed a sensor platform based on tunable laser absorption spectroscopy with a 3,266-nm interband cascade laser (ICL) as an optical source and a hollow waveguide (HWG) as a gas cell. The ICL wavelength was scanned across a C₂H₄ strong fundamental absorption band, and an interference-free C₂H₄ absorption line located at 3,060.76 cm⁻¹ was selected. Wavelength modulation spectroscopy with the second harmonic detection (WMS-2f) technique was used to improve the sensitivity. Furthermore, the HWG gas cell can achieve a long optical path in a very small volume to improve the time response.

The results show excellent linearity of the measured 2f signal and the C₂H₄ concentration with a correlation coefficient of 0.9997. Also, the response time is as short as about 10 s. The Allan variance analysis indicates that the detection limit can achieve 53 ppb with an integration time of 24 s.

The ethylene sensor has many meaningful applications in environmental monitoring, industrial production, national security and the biomedicine field.

The paper provides a novel sensor architecture which can be a versatile sensor platform for fast and sensitive trace-gas detection in the mid-infrared region.

Adhesion promoters: Some oleochemicals can promote the adhesion of polymers to various surfaces, e.g. stearic acid can increase the adhesion of polyolef ins to metals and to the surfaces of other polymers. Erucamide is effective in the lamination of cellophane to polyethylene films, and alumina‐modified iron stearate has been found effective in aiding the adhesion of polyethylene to steel surfaces. The effect of oleamide on the adhesion of polyethylene to aluminium and to nylon 6 has been studied. Stearic acid had an adhesion promoting role in polyethylene/aluminium laminated packaging film. Barium stearate can effect the adhesiveness of poly(vinyl chloride).

The article focuses on the magnetohydrodynamic (MHD) convective flow of MoS₂-SiO₂ /ethylene glycol (EG) hybrid nanofluid. The effectiveness of Hall current, periodically heating wall and shape factor of nanoparticles on the magnetized flow of hybrid nanocomposite molybdenum disulfide- silicon dioxide (MoS₂-SiO₂) suspended in ethylene glycol (EG) in a vertical rotating channel under the influence of strong magnetic dipole (Hall effect) and thermal radiation is assessed. One of the channel walls has an oscillatory temperature gradient. Four different shapes (i.e. brick, cylinder, platelet and blade) of nanoparticles disseminated in base fluid (EG) are considered for simulation of the flow.

The analytical solution of governing equations has been presented. Influences of emerging physical parameters on the velocity and temperature profiles, the shear stresses and the rate of heat transfer are pointed out and discussed via graphs and tables.

The analysis revealed that Hall parameter has suppressing behavior on the velocity profiles within the rotating channel. The impact of nanoparticle shape factor advances the temperature characteristics significantly in the rotating channel. Brick-shape nanoparticles put up relatively low-temperature distribution in the rotating channel. The Hall parameter reduces the amplitudes of the shear stresses at the channel wall. However, the radiation parameter enhances the amplitude of the rate of heat transfer at the channel wall.

The important technical advantage of hybrid composition of nanoparticles as a drug carrier is its stability, high thermal conductivity, high load carrying capacity, etc. The proposed model may be beneficial in biomedical engineering, automobile parts, mineral and cleaning oils manufacturing, rubber and plastic industries.

To the best of our knowledge, there is little or no report on the aspects of assessment of the effectiveness of Hall current and nanoparticle shape factor on an MHD flow and heat transfer of an electrically conducting MoS₂-SiO₂/EG ethylene glycol-based hybrid nanofluid confined in a vertical channel with periodically varying wall temperature subject to a rotating frame. The present work furnishes a robust benchmark for the dynamics of nanofluids.

The rate of copper dissolution in the presence of phosphoric acid‐alcohol mixtures was studied by measuring the limiting current density which represents that the rate of electropolishing is decreased by increasing phosphoric acid concentration, electrode height, and mole fraction of alcohol. Thermodynamic parameters are calculated. The rotating disk electrode is being used as a tool to study the influence of organic solvent addition on the rate of electropolishing of copper. Different reaction conditions such as temperature, speed of rotation of copper disk, the physical properties of solution are studied to obtain a dimensionless correlation between all these parameters. The data can be correlated by the following equations: Sh = 1.835 (Sc)^0.33 (Re)^0.36 (for ethylene glycol) Sh = 1.25 (Sc)^0.33 (Re)^0.5 (for glycerol) It is obvious that the exponent in the two cases denotes a laminar flow mechanism.

This paper aims to investigate the three-dimensional (3D) numerical simulations, based on the Navier–Stokes equations and the energy equation. Forced convection of a mixture of (60:40) percent ethylene glycol and water, was used as the base fluid and CuO nanoparticles, through a serpentine minichannel.

In this simulation, a serpentine mini-channel heat exchanger was simulated. The fluid studied in this simulation was composed of a mixture of (60:40) per cent ethylene glycol and water, was used as the base fluid and CuO nanoparticles. Four slabs and three serpentines were used in this study. The serpentine section is connected to the slab. Three equidistant circular channels (1 mm in diameter) were implemented inside the slab.

Results show that nanoparticles increase the fluid pressure drop and by changing volume fraction of nanoparticles from 0 to 1 per cent, the pressure drop of nanofluids increases between 42and 47 per cent, for Reynolds numbers from 100 to 500. The existence of serpentine bend in the minichannel heat exchanger causes the heat transfer rate to increase. Increase the volume fraction of nanoparticles reduces the fluid temperature at the outlet of the heat exchanger. The numerical results show that in Re = 500, at the beginning of the last slab in middle channel by changing volume fraction of nanoparticles from 0 to 2 per cent, local Nusselt number 57.40 per cent increase. The existence of the serpentine bend causes the heat transfer rate to increase.

Forced convection of a mixture of (60:40) per cent ethylene glycol and water by using of 3D numerical simulations, based on the Navier–Stokes equations.

Poly(ethylene terephthalate) (PET) waste from soft drink bottles was incorporated into palm olein alkyd to produce new polyol for use in polyurethane resins as surface protection on metal surfaces.

Alkyd was prepared from palm olein, glycerol and phthalic anhydride. PET underwent simultaneous glycolysis and transesterification reactions with the alkyd. Varying the amount of PET has led to polyols with different viscosities. Polyurethane resins were produced by reacting the polyols with toluene diisocyanate. The resins were coated on mild steel panels and cured. Performances of the cured films were tested.

The polyurethanes (PU) resin cured to a harder film with better thermal stability. Films showed excellent adhesion properties, while higher content of PET exhibited higher pencil hardness, better water, salt, acid and alkali resistance.

Other vegetable oils could also be used. The alkyd structure could be changed by formulation to have different functionality and the ability to incorporate higher amount of PET waste. Rate of glycolysis of PET could be increased by higher amount of ethylene glycol.

This method has managed to use waste PET in producing new polyol and PU resins. The cured films exhibit good mechanical and chemical properties, as well as excellent adhesion and thermal stability.

The non-biodegradable PET has created environmental pollution problems connected to littering and illegal landfilling. It has become necessary to pay greater attention to recycling PET bottles for obtaining valuable products.

This approach is different from the earlier reports, where PET was recycled to recover the raw materials.