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The purpose of this study was to find a suitable solvent to produce saffron edible extract with improved chemical properties.

Dried and pulverized stigmas of Crocus sativus L. (10 g) was extracted with 300 ml of solvents including distillated water (DW), ethanol/DW, methanol/DW, propylene glycol/DW, heptan/DW and hexan/DW, for three days at 25°C and then centrifuged at 3,000 rpm. Then, the extracts were evaporated using rotary evaporator at 40°C. The fiber and solvent-free extracts were then analyzed by UV spectrophotometer to detect saffron quality parameters including crocin, picrocrocin and safranal.

Distilled water/ethanol mixture as the extraction solvent caused larger amounts of the plant constituents to diffuse out to the extract compared to other treatments and also control. Polar solvents including distilled water, ethanol and propylene glycol (except methanol) were more effective in extracting crocin, picrocrocin and safranal than non-polar solvents.

No research had been done on production of saffron edible extract using the solvent studied in this survey. The novelty of this research is high and the results can be used industrially.

This study aims to use whiteness (WI) and yellowness indices (YI) that were calculated from the International Commission on Illumination (CIE) color parameter to evaluate the efficiency of some triazole fungicides [propiconazole (C₁₅H₁₇Cl₂N₃O₂) and tebuconazole (C₁₆H₂₂ClN₃O)] to protect wooden artifacts from fungal deterioration.

Archeological wooden samples were collected from some historical Islamic buildings in Cairo, Egypt. Three species of fungi were identified in previous work. Propiconazole and tebuconazole with different concentrations treated the infected wooden samples aged for different periods. WI and YI of studied samples were measured using UV spectrophotometer. Calibration and uncertainty estimation accompanied by color measurement were studied.

Studying the uncertainty sources of diffuse reflection of the standard white tiles revealed that the uncertainty of calibration for both the spectrophotometer and white tiles had the highest contribution. The treated samples with tebuconazole and propiconazole fungicides gave good resistance against fungal deterioration at 0.50% for WI and YI.

This study presents the importance of colorimetry in the conservation field because they are considered one of the most important criteria to evaluate conservation materials. From color measurements and their uncertainties, it became clear that triazole fungicides have good efficiency in the protection of wooden artifacts from fungal deterioration. The value of this study is that propiconazole and tebuconazole fungicides at 0.50% can be applied to archaeological wood that is endangered to improper conditions, especially in the case of high levels of relative humidity.

The purpose of this paper is to prepare poly(sodium‐p‐styrenesulphonate) (PSSNa) and investigate the effects of polymerisation conditions on the polymerisation rate of sodium styrenesulphonate (SSNa) and molecular weight of PSSNa.

SSNa polymers were prepared in both solution state and solid state by the γ‐ray radiation‐induced polymerisation. The molecular weight of polymer was measured with Ubbelohde viscosimeter and the molecular structure was characterised with IR and UV spectrophotometers.

In the radiation‐induced polymerisation of SSNa, factors such as irradiation dose rate, total dose, irradiation temperature, additives, etc. have impacts on the polymerisation rate, polymer yield and molecular weight of polymer. In aqueous solution, the reacted monomer number of SSNa and the total activation energy (Ea) of polymerisation were found to be 1.28×10⁴mol/100 eV and 12.98 kJ/mol, respectively. In the solid state, the SSNa was polymerised too, although the irradiation dose needed for the polymerisation was much higher comparing with that in the liquid state.

There are few reports on polymerisation process for the preparation of PSSNa via radiation techniques.

PSSNa has been widely used in many fields. Polymers prepared by radiation‐induced polymerisation could be used in special aspects such as biomedical application which requires products of higher purity.

The paper provides a way for the preparation of higher purity PSSNa without the use of polymerisation initiator.

The healthcare and hygiene textiles are gaining more importance for their eco-friendly and effective antimicrobial properties that have become essential to safeguard human beings from harmful microorganisms. The fabrics finished with chemical-based antimicrobial agents lead to environmental issues and are harmful to human beings. The paper aims to discuss these issues.

The present investigation is to develop a fabric with antioxidant and antimicrobial properties using the extracts of brown algae. Antimicrobial property has been imparted to the cotton fabric using microcapsules of brown seaweed extracts using the pad-dry-cure method. The presence of bioactive compounds and antioxidant activities of brown algae extracts was evaluated using gas chromatography-mass spectrometry and 2, 2-diphenyl-1-picrylhydrazyl radical scavenging technique, respectively. The total phenolic content of the seaweed extract was determined by the Folin-Ciocalteu method. The minimum bactericidal concentration and minimum inhibitory concentration methods were used to determine the antibacterial activity of the bacterial reduction percentage and parallel streak methods were used evaluate the antibacterial activity of seaweed-treated fabrics.

The methanol fraction of the treated fabric had the highest antioxidant activity (42.5+1.21 per cent), because the higher phenolic content traps the reactive oxygen species and develops the cells present in the skin. The results show that the lower inhibition (250 µg/mL) and bactericidal concentrations (1,000 µg/mL) possess higher antibacterial activity. The results also show that the treated fabric possess higher bacterial reduction of 96 per cent and higher zone of inhibition against Escherichia Coli and Staphylococcus Aureus which was about 35 mm and 40 mm. The air permeability, bending length and the wicking behaviour of the treated fabric were slightly reduced, but it has good bursting strength compared with the untreated fabric.

Such treated fabric is used for making wound dressing, surgical gowns, antibacterial socks and gauze bandage products in healthcare and hygiene textiles.

The purpose of this paper is to understand how the consistency between objective and perceived environmental uncertainty might affect supply chain flexibilities that cope with supply chain risk.

This study adopted a case study of comparative four companies in order to obtain an in-depth knowledge of the environmental conditions under which the companies implement different types of supply chain risk management (SCRM) strategies: logistics flexibility and relationship flexibility.

The case analysis not only distinguished the different effects of objective and perceived environmental uncertainty on supply chain flexibility, but also established the propositions about the effects of the consistency between objective and perceived environmental uncertainty on logistics flexibility and relationship flexibility in SCRM.

In principle, supply chain flexibility aims to cope with complex and turbulent environments. Yet, empirical findings about the effects of environmental uncertainty on supply chain flexibility are inconclusive. This study addressed this question by differentiating between objective and perceived environmental uncertainty as well as between logistics and relationship supply chain flexibilities.

The purpose of this paper is to evaluate the antioxidant activity and toxicity of Clinacanthus nutans leaves from three conventional extraction methods, i.e. maceration, Soxhlet and magnetic stirring.

Total flavonoid content (TFC) and phenolic content (TPC) were determined using colorimetric method of aluminum chloride and Folin-Ciocalteu (FC) assay, respectively. Antioxidant property of C. nutans was evaluated using 2,2'-diphenyl-1-pierylhydrazyl (DPPH) free radical scavenging assay. Cytotoxic activity of C. nutans against brine shrimp was evaluated based on LC50 (lethality concentration) after 24 h exposure to the plant extract.

The highest TPC of C. nutans was observed with Soxhlet extraction method (98.87 ± 10.43 mg of gallic acid equivalents (GAE/g) followed by maceration (68.77 ± 2.45 mg of GAE/g) and magnetic stirring (46.75 ± 2.45 mg of GAE/g). Interestingly, remarkable highest TFC was observed with magnetic stirring (568.90 ± 4.85 mg of rutin equivalent (RE)/g) followed by maceration (249.60 ± 2.79 mg of RE/g) and Soxhlet (174.8 ± 1.74 mg of RE/g). On the other hands, the extract obtained using maceration method showed the highest antioxidant activity (IC50: 14.18 mg/mL compared to ascorbic acid 144.36 µg/mL). Cytotoxicity of C. nutans from all extraction methods showed similar LC50 values with maceration (3.81 mg/mL), Soxhlet (2.61 mg/mL) and magnetic stirring (4.56 mg/mL), respectively.

Both phenolic and flavonoids are responsible for the antioxidant activity, of C. nutans extracts. Based on Meyer's toxicity index, all extracts were nontoxic (LC50>1 mg/mL).

The purpose of this paper is to experimentally investigate the effect of aluminium oxide (Al₂O₃) nanoparticles on gear oil (SAE EP 90) as a lubricant in heavy earth moving machinery (HEMM).

Particle size distribution, viscosity, density, stability and other rheological properties have been measured. The variations in rheological properties with varying nanoparticle volume fraction and temperature have been investigated at atmospheric pressure over a temperature range of 15-40°C. Classical as well as modified Krieger – Dougherty models have been used for finding out viscosity variation and a new empirical model has been presented.

Dynamic light scattering data confirm the presence of large agglomeration of about 5.5 times of primary nanoparticles in nanofluid. Nanofluid starts behaving as a non-Newtonian fluid with increasing nanoparticle volume fraction. Viscosity of nanofluid is enhanced by 1.7 times of base fluid with 2 per cent volume fraction of Al₂O₃ nanoparticles, while it significantly decreases with increase in temperature. The stability of nanofluid decreases with increase in nanoparticle volume fraction due to settling down of nanoparticles. It has also been observed that shear thinning increases with increasing nanoparticle volume fraction.

It is expected that these findings will contribute towards the improvement in rheological and thermal properties of the conventional lubricants used in HEMM. The outcome may help the designers, researchers and manufacturers of the HEMM.

Most of the previous research in this field is confined with base fluid as water, ethylene glycol, transformer oil, etc. Gear oil in HEMM performs under high mechanical and thermal load. The Al₂O₃/gear oil nanofluid is expected to have better cooling and lubrication properties.

The aim of this paper is to study the effect of the parametric sensitivity of all critical parameters of feed water and other operating variables on the corrosion rate and oxide scale deposition on economizer tubes of a typical coal-fired 250-MW boiler.

In this paper, a multilayer perceptron-based artificial neural network (ANN) model has been developed to envisage the corrosion rate and oxide scale deposition rate in economizer tubes of a coal-fired boiler. The neural network architecture has been optimized using an efficient gradient-based network optimization algorithm to minimize the training and testing errors rapidly during simulation runs.

The parametric sensitivity of all critical parameters of feed water and other operating variables on the corrosion rate and oxide scale deposition activities has been investigated. It has been observed that dissolved oxygen, dissolved copper content, residual hydrazine content and pH of the feed water have a relatively predominant influence on the corrosion rate, whereas dissolved iron content, silica content, pH and temperature of the feed water have a moderately major influence on oxide scale deposition phenomenon. There has been very good agreement between ANN model predictions and the measured values of corrosion rate and oxide scale deposition rate substantiated by the regression fit between these values.

This paper details the development of an alternative model to accurately predict corrosion rate and deposition rate on the inner surface of economizer tubes of a boiler over first principle-based kinetic model.

Carotenoids are pigments that have significant value as colorants and antioxidants in pharmaceutical, food, textile and cosmetic industries. Owing to its high demand, this study aims to identify ß-carotene producing bacteria from different terrestrial habitats of Jaipur region.

In this paper, standard isolation and purification process was used, followed by colony morphology and biochemical characterization of ß-carotene producing bacteria. ß-carotene concentration was determined quantitatively using spectrophotometric method.

Out of 43 isolates, 21 isolates showed peak range between 400 and 500 nm confirming the presence of carotenoids. Only one bacteria SAN-A has capacity to produce ß-carotene confirmed by the thin layer chromatography and high performance liquid chromatography (HPLC) with a yield of 1.68 mg/l. The 2, 2-Diphenyl-2-picrylhydrazil (DPPH) assay showed an IC50 value of 4.0 mg/ml.

The present study revealed the presence of ß-carotene producing bacteria in the soil of different terrestrial habitat of Jaipur region which can be exploited as an economical source for ß-carotene production.

The purpose of this paper is to identify the most dominant pigment of pomegranate explants for natural color coatings and detect the presence of phytochemical constituents and comparison of the antioxidant activities.

Extracts of leaf, stem, peel and seed of in vitro and in vivo growth cultures were prepared for phytochemical constituent and antioxidant activity. The supernatant from 95 per cent methanol was mixed with 15 per cent polyvinyl alcohol (PVA) with the ratio of 1:1 to form a coating system.

Although glycosides was not found in this species, tests for tannins and flavonoids were positive in all samples. The IC50 values were also comparable to commercial antioxidant ascorbic acid with 34.92 per cent inhibition. Chlorophyll a and b were detected in stem and leaf using UV-photospectrometer in 420 and 645 nm wavelengths ranges. The effects of heat and salt on the stability of natural dye colorants mixed with polyvinyl alcohol to form a basic coating system were indicated negatively in in vivo and in vitro growth cultures.

The paper shows that further improvement with co-pigmentations may give a notable mixture from pomegranate extraction for the paint materials or nail varnish. It was also indicated that pomegranate contains some compounds such as polyphenolics that can donate electron/hydrogen easily.