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Artificial fruit ripening is hazardous to mankind. In the recent past, artificial fruit ripening is increasing gradually due to its commercial benefits. To discriminate the type of fruit ripening involved at the vendors’ side, there is a great demand for on-sight ethylene detection in a nondestructive manner. Therefore, this study aims to deal with a comparison of various laboratory and portable methods developed so far with high-performance metrics to identify the ethylene detection at fruit ripening site.

This paper focuses on various types of technologies proposed up to date in ethylene detection, fabrication methods and signal conditioning circuits for ethylene detection in parts per million and parts per billion levels. The authors have already developed an infrared (IR) sensor to detect ethylene and also developed a lab-based setup belonging to the electrochemical sensing methods to detect ethylene for the fruit ripening application.

The authors have developed an electrochemical sensor based on multi-walled carbon nanotubes whose performance is relatively higher than the sensors that were previously reported in terms of material, sensitivity and selectivity. For identifying the best sensing technology for optimization of ethylene detection for fruit ripening discrimination process, authors have developed an IR-based ethylene sensor and also semiconducting metal-oxide ethylene sensor which are all compared with literature-based comparable parameters. This review paper mainly focuses on the potential possibilities for developing portable ethylene sensing devices for investigation applications.

The authors have elaborately discussed the new chemical and physical methods of ethylene detection and quantification from their own developed methods and also the key findings of the methods proposed by fellow researchers working on this field. The authors would like to declare that the extensive analysis carried out in this technical survey could be used for developing a cost-effective and high-performance portable ethylene sensing device for fruit ripening and discrimination applications.

This work encompasses the various laboratory-based and portable methods evolved in recent times for sensitive and selective detection of ethylene for fruit-ripening application. The role of ethylene in natural and artificial fruit ripening and the associated health hazards are well known. So there is a growing need for ethylene detection. This paper aims to highlight potential methods developed for ethylene detection by various researchers, including ours. Intense efforts by various researchers have been on since 2014 for societal benefits.

The paper focuses on types of sensors, fabrication methods and signal conditioning circuits for ethylene detection in ppm levels for various applications. The authors have already designed, developed a laboratory-based set-up belonging to the electrochemical and optical methods for detection of ethylene.

The authors have developed a carbon nanotube (CNT)-based chemical sensor whose performance is higher than the reported sensor in terms of material, sensitivity and response, the sensor element being multi-walled carbon nanotube (MWCNT) in comparison to single-walled carbon nanotube (SWCNT). Also the authors have developed infrared (IR)-based physical sensor for the first time based on the strong IR absorption of ethylene at 10.6 µm. These methods have been compared with literature based on comparable parameters. The review highlights the potential possibilities for development of portable device for field applications.

The authors have reported new chemical and physical sensors for ethylene detection and quantification. It is demonstrated that it could be used for fruit-ripening applications A comparison of reported methods and potential opportunities is discussed.

The purpose of this paper was to develop a chemo-resistive sensor based on TiO₂–WO₃ composite material to detect and estimate ethylene released from the fruit ripening process to ensure food safety.

The ethylene sensor has been fabricated using TiO₂–WO₃ composite material through the sol-gel method.

The sensitivity of the sensor obtained using the pre-calibrated ethylene is found to be 46.2 per cent at 200 ppm ethylene concentration, and the proposed sensor could measure 8 ppm as the lowest concentration.

The sensor was tested for continuous ethylene detection during natural ripening of fruits and hence is useful for ensuring food safety through discrimination of the type of fruit ripening. A TiO₂–WO₃ composite ethylene sensor is developed for the first time.

The purpose of this paper is to determine compatibility groups of different fruits and vegetables that can be stored and transported together based upon their requirements for temperature, relative humidity, odour and ethylene production. Pre-cooling which is necessary to prepare the commodity for subsequent shipping and safe storage is also discussed.

The methodology used in this journal is an attempt to form clusters/groups of storing together 43 identified fruits and vegetables based on four important parameters, namely, temperature, relative humidity, odour and ethylene production. An agglomerative hierarchical clustering algorithm is used to build a cluster hierarchy that is commonly displayed as a tree diagram called dendrogram. The same is further analyzed using K-means clustering to find clusters of comparable spatial extent. The results obtained from the analytics are compared with the available data of grouping fruits and vegetables.

This study investigates the usefulness and efficacy of the proposed clustering approach for storage and transportation of different fruits and vegetables that will eventually save huge investment made in terms of developing infrastructure components and energy consumption. This will enable the investors to adopt it for using the space more effectively and also reducing food wastage.

Due to limited research and development (R&D) data pertaining to storage parameters of different fruits and vegetables on the basis of temperature, relative humidity, ethylene production/sensitivity, odour and pre-cooling, information from different available sources have been utilized. India needs to develop its own crop specific R&D data, since the conditions for soil, water and environment vary when compared to other countries. Due to the limited availability of the research data, various multi-criteria approaches used in other areas have been applied to this paper. Future studies might be interested in considering other relevant variables depending upon R&D and data availability.

With the increase in population, the demand for food is also increasing. To meet such growing demand and provide quality and nutritional food, it is important to have a clear methodology in terms of compatibility grouping for utilizing the available storage space for multi-commodity produce and during transportation. The methodology used shall enable the practitioners to understand the importance of temperature, humidity, odour and ethylene sensitivity for storage and transportation of perishables.

This approach shall be useful for decision making by farmers, Farmer Producer Organization, cold-storage owners, practicing managers, policy makers and researchers in the areas of cold-chain management and will provide an opportunity to use the available space in the cold storage for storing different fruits and vegetables, thereby facilitating optimum use of infrastructure and resources. This will enable the investors to utilize the space more effectively and also reduce food wastage. It shall also facilitate organizations to manage their logistic activities to gain competitive advantage.

The proposed model would help decision makers to resolve the issues related to the selection of storing different perishable commodities together. From the secondary research, not much research papers have been found where such a multi-criteria clustering approach has been applied for the storage of fruits and vegetables incorporating four important parameters relevant for storage and transportation.

The purpose of this paper is to research the durability of the adhesive‐poly(ethylene terephthalate) film joints.

The adhesive‐poly(ethylene terephthalate) joints are prepared with poly ethylene terephthalate film synthesised from thioglycolic acid, terpene hydrocarbon resin and acetone resolution at room temperature. These joints are characterised by methods of peel strength tests, energy dispersive X‐ray spectroscopy (EDX) and analysis of glass transition temperature (T_g) to examine their durability.

Peel strength tests and EDX analyses prove that water diffusion in different humidity aging conditions causes similar changes, namely having the time‐temperature equivalence at 45°C for 200, 300, 500 and 600 h, respectively, almost corresponding with those at 55°C for 100, 200, 300 and 400 h, respectively, and at 65°C for 50, 100, 150 and 200 h, respectively. The changes in EDX spectra of adhesive‐poly(ethylene terephthalate) film joints indicate that the rate of water penetration in the adhesive is faster than that in the poly(ethylene terephthalate) film. In humidity aging process, the decline ratio of peel strength of adhesive‐poly(ethylene terephthalate) film joints treated with Co⁶⁰ irradiation is lower than that treated with acetone washing or chemical treatment.

The paper shows that using EDX for analysis of durability of adhesive film joints is of significance to industrial process.

The purpose of this paper is to deal with an optimal consolidation problem for fresh agricultural products (e.g. fruits and vegetables) in a multi-temperature joint distribution (MTJD) system that is developed to resolve the challenge of timely delivery of small and diverse shipments in food cold chains.

An integer programming optimization model is developed to consolidate a set of agricultural shipments with different storage requirements into a number of distinct containers according to the classification criteria. The formulated model for consolidating fresh agricultural products is evaluated using numerical examples.

Critical factors that affect the quality or shelf life of fresh agricultural products are examined to form the criteria for classifying the storage requirements of these products. The formulated model can minimize the consolidation cost and the loss of product value due to a reduction in shelf life after consolidation.

Although the decision model for product consolidation developed in this paper takes into account practical concerns as much as possible, some additional conditions in the cold chain of fresh fruits and vegetables can be included to further enhance the application of the proposed consolidation model.

Provided that the container environment is appropriately controlled, the shelf life of fresh fruits and vegetables can be maintained during the logistics process. As a result, product quality can be managed to reduce product loss.

This paper adopts temperature, relative humidity and ethylene production, which generally affect the quality and shelf life of fresh agricultural products, as the main factors for determining the product consolidation. It is among the first to deal with the optimal consolidation of fresh agricultural products in the MTJD system with the consideration of product shelf life.

“Pressure polymers” is a convenient short name for vinyl acetate‐ethylene, and vinyl acetate‐ethylene‐vinyl chloride copolymers; the use of ethylene in particular necessitates operating the polymerisation reaction at appreciable pressures, in some cases up to 200 atm. However, the use of pressure in emulsion polymerisation is not an end in itself, interesting though the chemical and engineering challenge has proved to be: the development has arisen from the search for paint media with the best balance of cost and efficiency. Our first experimental vinyl acetate‐ethylene emulsions were shown at the 1966 OCCA Technical Exhibition; one of these grades has been in use on a limited scale for some years, and is now in bulk production at our Warrington factory, which began operating in October 1974. We subsequently undertook work on copolymers and terpolymers involving vinyl chloride, and bulk production of selected products has now started at Warrington.

HAVING IMPORTANT USES AS SYNTHETIC lubricants, polyglycols are now being manufactured for the first time in Canada at a new fully‐integrated $25 million petrochemicals and polyethylene plant recently put on stream at Montreal East, Quebec, by the Carbide Chemicals Company, Division of Union Carbide Canada Limited, which is a subsidiary of Union Carbide Corporation, New York. At the new plant specialised equipment converts petroleum gas concentrates from three neighbouring refineries into ethylene oxide, ethylene glycol, other ethylene oxide derivatives and polyethylene.

The purpose of this paper is to carry out a hydrodynamic and thermal analysis of turbulent forced-convection flows of pure water, pure ethylene glycol and water-ethylene glycol mixture, as base fluids dispersed by Al₂O₃ nano-sized solid particles, through a constant temperature-surfaced rectangular cross-section channel with detached and attached obstacles, using a computational fluid dynamics (CFD) technique. Effects of various base fluids and different Al₂O₃ nano-sized solid particle solid volume fractions with Reynolds numbers ranging from 5,000 to 50,000 were analyzed. The contour plots of dynamic pressure, stream-function, velocity-magnitude, axial velocity, transverse velocity, turbulent intensity, turbulent kinetic energy, turbulent viscosity and temperature fields, the axial velocity profiles, the local and average Nusselt numbers, as well as the local and average coefficients of skin friction, were obtained and investigated numerically.

The fluid flow and temperature fields were simulated using the Commercial CFD Software FLUENT. The same package included a preprocessor GAMBIT which was used to create the mesh needed for the solver. The RANS equations, along with the standard k-epsilon turbulence model and the energy equation were used to control the channel flow model. All the equations were discretized by the finite volume method using a two-dimensional formulation, using the semi-implicit method for pressure-linked equations pressure-velocity coupling algorithm. With regard to the flow characteristics, the interpolation QUICK scheme was applied, and a second-order upwind scheme was used for the pressure terms. The under-relaxation was changed between the values 0.3 and 1.0 to control the update of the computed variables at each iteration. Moreover, various grid systems were tested to analyze the effect of the grid size on the numerical solution. Then, the solutions are said to be converging when the normalized residuals are smaller than 10-12 and 10-9 for the energy equation and the other variables, respectively. The equations were iterated by the solver till it reached the needed residuals or when it stabilized at a fixed value.

The result analysis showed that the pure ethylene glycol with Al₂O₃ nanoparticles showed a significant heat transfer enhancement, in terms of local and average Nusselt numbers, compared with other pure or mixed fluid-based nanofluids, with low-pressure losses in terms of local and average skin friction coefficients.

The present research ended up at interesting results which constitute a valuable contribution to the improvement of the knowledge basis of professional work through research related to turbulent flow forced-convection within channels supplied with obstacles, and especially inside heat exchangers and solar flat plate collectors.