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This study aims to get the essential data of the solubility and diffusion coefficient of gas in jet fuel for appropriately designing a kind of on-board inert gas generation system.

A test apparatus based on pressure–decay method was constructed to measure solubility and diffusion coefficient of gas in liquid. The test apparatus and method were verified via measurement of solubility and diffusion of CO₂ in the pure water.

The solubility of CO₂ and O₂ in RP-3 jet fuel with the temperature from 253 to 313 K under three various pressures were measured and compared with theoretical value calculated by a relative density method provided in the standard of ASTM D2780-92, and the deviation is within 10 per cent. The diffusion coefficients of CO₂ and O₂ in RP-3 jet fuel are determined by monitoring the gas pressure in a hermetic cell versus time with the temperature from 253 to 333 K. The measured diffusivity-temperature relation can be well fitted through the Arrhenius equation for engineering applications. The obtained correlation can be used to predict the diffusion coefficient of CO₂ and O₂ in RP-3 jet fuel under a wide temperature range.

The semi-empirical correlation of solubility and diffusion coefficient in RP-3 jet fuel obtained from the experimental data could be used to support the design of an inert gas generation system.

There are no essential data of solubility and diffusion of CO₂ and O₂ in RP-3 jet fuel; therefore, it is fatal if the quantity and rate of mass transfer of CO₂ and O₂ in RP-3 jet fuel must be assessed, e.g. during the design of green on-board inert gas generation system.

This work aims to explain the effect of common salt on absorbance spectra and solubility of textile direct dyes, which is important in analysing and reusing wastewater of dyeing process.

Several textile dyes such as Direct red 243, Direct yellow 86 and Direct blue 201 solutions with and without NaCl salt were used to study the effect of common salt on solubility of textile direct dyes. Several methods such as derivative spectrophotometry, principal component analysis and colorimetric techniques were used to analyse the absorbance spectra of dye solution.

The obtained results indicate that the effect of common salt on absorbance spectra and solubility of textile direct dye depends on the chemical structure of dyes. The NaCl salt significantly affects the solubility of Direct red 243 (red dye) and Direct yellow 86 (yellow dye) which have Azo compounds containing four SO₃ functional groups. But the NaCl salt does not change the solubility of Direct blue 201 (Blue dye) which has Azo compound containing two SO₃ functional groups. Also, the NaCl salt decreases the accuracy of dye concentration prediction.

During reusing wastewater of dyeing process, the amount of dyes has been evaluated via absorbance spectra of dye solution.

This work explains the effect of common salt on solubility of textile direct dyes and the accuracy of dyes concentration prediction.

To overcome the need of seasonal fruit ber, consumers prefer to use fruits in such a form that can be prepared easily or consumed instantly. By transforming them into powders, they can be effortlessly attained as well as preserved, stored and processed.

To optimize the spray drying conditions for development of ber fruit powder, response surface methodology was used. The experimental design consisted of 13 runs. The levels of independent variables, i.e. inlet air temperature, varied from 153.79ºC to 196.21ºC and maltodextrin concentration, from 4.17 to 9.83 per cent. The responses were moisture content, bulk density, solubility, vitamin C, ΔE and L value.

The second-order polynomial model fitted for moisture content, bulk density, solubility, vitamin C, ΔE and L value was highly significant (p < 0.001) for each response. The inlet air temperature showed maximum influence on moisture content, bulk density, solubility and vitamin C, whereas the maltodextrin concentration showed maximum influence on bulk density, solubility, ΔE and L value. The predicted values were attained as moisture 4.90 per cent, bulk density 0.35g/ml, solubility 89.11 per cent, vitamin C 91.06mg/100g, ΔE 31.03 and L 87.78. The recommended optimum spray drying conditions were inlet air temperature and maltodextrin concentration of 166.64°C and 9.26 per cent, respectively.

Spray drying of the underused Indian fruit ber has enhanced its utility. Ber powder can further be used as an instant beverage, in sweets, as a flavoring agent and in soft drinks.

The main purpose of this paper is to produce high‐nitrogen martensitic stainless steels (HNMSS) using a conventional induction furnace with better mechanical properties and to improve the properties by thermo‐mechanical treatment (TMT).

Production of two types of HNMSS alloys with Chromium – 8.22 and 15.84 wt% was carried out using a conventional melting furnace. The theoretical nitrogen solubility of the produced alloys was calculated and compared with the actual nitrogen solubility of the alloys. The produced alloys were subjected to TMT, characterized by hardness measurement, tensile testing micro examinations in the as cast, hardened, TMT treated and TMT hardened and tempered conditions.

The actual nitrogen solubility achieved in the HNMSS specimens was in agreement with the calculated theoretical nitrogen solubility using thermodynamic relationships. Thermo‐mechanically treated specimens exhibited the break‐up and refinement of the original coarse cast structure by repeated recrystallization as fine grain size in the austenitic condition and reduced proportion of residual deformed δ ferrite. Thermo‐mechanically treated, hardened and tempered specimens showed higher hardness up to 525 VHN, with strength and toughness.

In the conventional melting process, purging nitrogen into the melt and increasing the percentage of nitrogen is the primary limitation and retaining the same into the solution during thermo‐mechanical treatment is the secondary limitation.

Work on melting of nitrogenated steels using controlled atmospheric conditions with special equipment was carried out earlier. This practice cannot be adopted on a commercial basis, where mass production is the prime requirement. Therefore, the uniqueness of this paper lies in communicating the melting practice of HNMSS using a conventional induction furnace followed by the optimum TMT. This takes the production and TMT of HNMSS into the commercial casting industry for mass production.

The purpose of the present study is first to develop a hydroxyl-functionalized ketonic resin for coating applications and to establish a standard characterization protocol; second, to quantify the effects of various operating parameters on resin properties and to develop mathematical models to predict the product properties; and third, to carry out the compatibility study between the in-house developed resins and commercially available resins.

Self-polymerization reactions were conducted in a batch reactor. Effects of reaction time, temperature, catalyst concentration and reactor pressure on product properties have been studied. Hydroxyl value, iodine value, solubility, rheology, gel permeation chromatography (GPC), thermogravimetric analysis (TGA), scanning electron microscope (SEM) and the X-ray diffraction (XRD) analysis were carried out to characterize the product properties. Mark–Houwink correlation was used to predict molecular weight of the resins.

The study shows that hydroxyl value and softening temperature (ST) of the product increased with the increase of reaction temperature, duration of reaction and alkali concentration. However, the solubility value of the resins decreased with the increase of temperature, time and alkali concentration. Regression models were developed to predict the optimum conditions for obtaining a desired quality of resin. The number-average molecular weight of the developed resins was in the range of 450-1150. The products are thermally stable up to around 200°C, and adequately soluble in many commercial solvents.

The ketonic resin can be used as a substitute of phenolic resins which are prepared from more hazardous materials monomers such as phenolic and aldehyde compounds.

The resin can be used as a substitute of more hazardous materials such as phenolic and aldehyde compounds.

This paper details the synthesis of ketonic resin from cyclohexanone and its compatibility. It also investigates the optimization of operating parameters to obtain a desire product.

This paper aims to discuss the successful 3D printing of styrene–ethylene–butylene–styrene (SEBS) block copolymers using solvent-cast 3D printing (SC-3DP) technique.

Three different Kraton grade SEBS block copolymers were used to prepare viscous polymer solutions (ink) in three different solvents, namely, toluene, cyclopentane and tetrahydrofuran. Hansen solubility parameters (HSPs) were taken into account to understand the solvent–polymer interactions. Ultraviolet–visible spectroscopy was used to analyze transmittance behavior of different inks. Printability of ink samples was compared in terms of shape retention capability, solvent evaporation and shear viscosity. Dimensional deviations in 3D-printed parts were evaluated in terms of percentage shrinkage. Surface morphology of 3D-printed parts was investigated by scanning electron microscope. In addition, mechanical properties and rheology of the SC-3D-printed SEBS samples were also investigated.

HSP analysis revealed toluene to be the most suitable solvent for SC-3DP. Cyclopentane showed a strong preferential solubility toward the ethylene–butylene block. Microscopic surface cracks were present on tetrahydrofuran ink-based 3D-printed samples. SC-3D-printed samples exhibited high elongation at break (up to 2,200%) and low tension set (up to 9%).

SC-3DP proves to be an effective fabrication route for complex SEBS parts overcoming the challenges associated with fused deposition modeling.

To the best of authors’ knowledge, this is the first report investigating the effect of different solvents on physicomechanical properties of SC-3D-printed SEBS block copolymer samples.

This paper attempted to show the potential relationship between five different interaction coefficients relating solvents and polymers. This review addressed primarily a comparison between the polymer-solvent interaction coefficients obtained from two different types of models. These two primary polymer-solvent interaction coefficients included the Flory-Huggins interaction coefficient developed from thermodynamic colligative properties and the polymer-solvent Sudduth interaction coefficient obtained from the generalized viscosity equation. The other three interaction coefficients included Hildebrand solubility parameter and the interaction coefficients or constants for the Huggins and Kraemers models that are normally generated from viscosity measurements. The paper aims to discuss these issues.

These five different interaction coefficients were compared from theoretical considerations as well as on the basis of available experimental data.

Remarkably the polymer-solvent interaction coefficients for both Flory-Huggins interaction coefficient and the Sudduth interaction coefficient were found to be dimensionless and approximately of the same value. In addition, when both interaction coefficients are negative then both describe solvents. In addition, both interaction coefficients describe a plasticizer when they are in the range of 0 to ½. Finally both interaction coefficients describe a non-solvent or a suspension when both are greater than 1. The Hildebrand solubility parameter was found to be directly related to the Flory-Huggins interaction coefficient. The viscosity constants for the Huggins and Kraemers models were found to be included as subsets of the Sudduth generalized viscosity model.

The strong apparent relationship between these five different interaction coefficients to predict the interaction between polymers and solvents is strongly indicated based on the results from this study. However, approximately half of these interaction coefficients have been derived to be evaluated from colligative properties and half were derived to be evaluated from viscosity measurements.

In general, it is much easier to obtain viscosity measurements compared to the evaluation of the colligative properties. Therefore, if a direct relationship can be shown between these five different interaction coefficients, then it would appear to be much easier to evaluate polymer-solvent interactions from the interaction coefficients obtained from viscosity measurements.

This is the first time that these five interaction coefficients have been compared in such a way that shows their direct relationship even though half of these interaction coefficients have been derived to be evaluated from colligative properties and half were derived to be evaluated from viscosity measurements.

This paper aims to study previously prepared and fully characterized chitosan nanoparticles (CNPs) as a starting substrate and microwave initiation technique for grafting acrylic acid (AA). This was done to see the influence of both CNPs with respect to well-dispersed nanosized particles, large surface areas, biodegradability, biocompatibility and reactivity and microwave initiation technique with respect to reduction in organic solvents, toxic chemical initiator and exposer time on exploiting the graft yield % and enhancing water solubility and antibacterial properties.

For evaluating the best accurate standard metrological method for calculating the graft yield %, the grafting parameters were stated in terms of graft yield percent and measured gravimetrically (based on dry weight method) and titrimetrically (based on carboxyl content). Microwave power, AA and CNPs concentrations and reaction duration were shown to be the most important parameters influencing the grafting process.

The optimum reaction conditions were obtained when CNPs 1.5 g, AA 150 bows, microwave irradiation power 500 W and reaction duration 120 s were used. Various analytical methods were used to characterize CNPs and poly(AA)–CNPs graft copolymers. According to the findings, Fourier transform infrared spectroscopy examination determines the attachment of carboxyl groups to CNPs chains. The thermogravimetric analysis revealed that the copolymers were more thermally stable than CNPs counterparts. Furthermore, the resulting copolymers were shown to have greater water solubility biodegradability resistance and antibacterial properties than CNPs counterpart. Finally, a preliminary mechanism demonstrating all occasions that occur during the polymerization reaction has been proposed.

The advancement addressed here is undertaken using previously prepared and fully characterized CNPs as a green bio-nanocompatible polymer and microwave initiation technique as green and efficient tool with respect to reduction in organic solvents toxic chemical initiator and exposer time for grafting AA.

This paper investigates the effect of three different treatments, namely (i) sunlight exposures, (ii) bleaching and (iii) perming on the damage of the keratin fibres (with the use of human hair). Scanning electron microscopy was applied to examine the surface morphology of the samples. Hair samples appeared to be rougher and their scales diminished after the treatments. The degree of colour change of samples was measured using a diffuse reflectance spectrophotometer. All three different treatments caused a certain degree of colour change on the samples. Urea bisulphite solubility test was also employed to investigate the alkaline damage of samples.

The results illustrated that the urea bisulphite solubility of samples conformably decreased when they were subject to these three types of treatments. With respect to the tensile strength property, the results indicate that the breaking load of treated samples decreased dramatically after undergoing three different types of treatments. On evaluating the test results, it was concluded that the bleaching process imparted the most severe damages to hair. The results of the different test methods were evaluated and discussed.

The purpose of this study was carried out to explore the potential use of carrageenan extracted from marine red seaweed (Kappaphycus alvarezii) collected from Munaikadu, Mandapam region, Ramanathapuram district, Tamil Nadu.

Biodegradable film was developed by using carrageenan extracted by using alcohol extraction method. To improve the mechanical properties of the film, rice starch was incorporated. The biodegradable films were made by phase inversion method with varied carrageenan concentration of 1%, 1.5% and 2% (w/v) and rice starch with concentration of 0%, 1%, 1.5% and 2% (w/v). Physical properties, optical properties, mechanical properties and other properties such as biodegradability, solubility and water vapor permeability of the developed biodegradable films were characterized. The results were analyzed in design expert software using Box–Behnken design.

Results show that the biodegradable film’s mechanical and water vapor permeability increases with an increase in carrageenan and rice starch concentration. The optimized film structure was obtained with carrageenan and rice starch composition of 1.5% and 2%, respectively.

The results shown a broad spectrum of commercial applications and future rice starch possibilities incorporated in the carrageenan-based biodegradable film.