Optimization of the alternative treatment methods for Ceiba pentandra (L.) Gaertn (kapok) fiber using response surface methodology

Abstract

Ceiba pentandra (L.) Gaertn (kapok) fiber, a natural and renewable material, has received increasing attention in recent years for its intrinsic properties. In this study, pretreatment of kapok fiber was performed in a green way by using atmospheric plasma, together with pectinase and lipase enzymes and no hazardous chemicals was used. A response surface methodology (Box-Behnken experimental design) has been used to design and optimize an environmentally friendly and sustainable scouring process for kapok fibers. Predicted values provided from regression model and the actual experimental values exhibited close relationship. The effects of the treatments on the hydrophility, whiteness index and color yield of the kapok fibers have been discussed. The structure of the fibers was investigated by scanning electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction analyses. Results showed that atmospheric plasma?+?pectinase and atmospheric plasma?+?lipase treatments are ecofriendly alternatives for kapok fiber treatments.     

Preliminary characterisation of cornelian cherry (Cornusmas L.) genotypes for their physico-chemical properties

Fruit weight, antioxidant capacity, total anthocyanins, total phenolics, ascorbic acid, soluble solid content (SSC), reducing sugar and acidity of a number of selected cornelian cherry (Cornusmas L.) genotypes of varied pigmentation were investigated. Two methods, namely β-carotene bleaching and ferric reducing antioxidant power (FRAP) were used to determine total antioxidant capacity, while Folin–Ciocalteu reagent was used to determine total phenols. Fruit weight, SSC and ascorbic acid content of genotypes were 2.09–9.17; 12.53–21.17% and 29–112 mg/100 g, respectively. Antioxidant activity and total phenolic content varied among genotypes and 44-18 genotype had the highest antioxidant capacity using both methods. This genotype also had the highest total phenolic (74.8 mg GAE/g DW) and total anthocyanin (115 mg cyanidin-3-glucoside equivalents /100 g FW) content. There are linear relationships between antioxidant capacities and total phenols. The present study demonstrates the potential of certain cornelian cherry genotypes, notably 44-18, for improvement of nutritional value through germplasm enhancement programmes.     

Phenolic profile,antioxidant, anticholinesterase,and anti-tyrosinase activities of the various extracts of Ferula elaeochytris and Sideritis stricta

In this study, the antioxidant, anticholinesterase, and anti-tyrosinase properties of (hexane, acetone, methanol, and water) extracts of Ferula elaeochytris and Sideritis stricta were determined with the total phenolic and flavonoid contents. The phenolic profile of the methanol and water extracts was analysed using HPLC-DAD. Protocatechuic acid was found as the major phenolic compound in the methanol (116.3 ± 3.1 µg/g) and water extracts (69.4 ± 1.3 µg/g) of F. elaeochytris. Coumarins (253.9 ± 4.1 µg/g) and catechin hydrate (175.2 ± 2.9 µg/g) were the most abundant phenolic compounds in the methanol and water extracts of S. stricta. β-carotene–linoleic acid, DPPH^?, ABTS^?+, CUPRAC, and metal-chelating assays were used to evaluate antioxidant properties of the extracts. The methanol and water extracts of F. elaeochytris and the acetone and methanol extracts of S. stricta containing the highest amount of total phenolic and flavonoid contents showed the highest antioxidant activities in β-carotene–linoleic acid, DPPH^?, ABTS^?+, and CUPRAC assays. The enzyme inhibitory potential of extracts was investigated against key enzymes involved in neurodegenerative (acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)) and skin (tyrosinase) disorders. In the cholinesterase inhibitory assays, the hexane extracts of two species exhibited the best activity against AChE, while the hexane extract of F. elaeochytris and the methanol extract of S. stricta observed to be the most active against BChE. As for anti-tyrosinase activity results of extracts, the only acetone and methanol extracts showed mild inhibitory activity for both species.     

A risk-averse approach to simulation optimization with multiple responses

This article considers risk-averse simulation optimization problems, where the risk measure is the well-known Average Value-at-Risk (also known as Conditional Value-at-Risk). Furthermore, this article combines Taguchi’s robustness with Response Surface Methodology (RSM), which results in a novel, robust RSM to solve such risk-averse problems. In case the risk-averse problem is convex, the conic quadratic reformulation of the problem is provided, which can be solved very efficiently. The proposed robust RSM is applied to both an inventory optimization problem with a service-level constraint and a call-center problem; the results obtained for the risk-averse problem and its benchmark problem, where the risk measure is the variance, are intuitively sound and interesting.     

Manifestation of an adaptive neuro-fuzzy model on landslide susceptibility mapping: Klang valley,Malaysia

The purpose of the present paper is to manifest the results of the neuro-fuzzy model using remote sensing data and GIS for landslide susceptibility analysis in a part of the Klang Valley areas i Malaysia. Landslide locations in the study area were identified by interpreting aerial photographs and satellite images, supported by extensive field surveys. SPOT 5 satellite imagery was used to map vegetation index. Maps of topography, lineaments, NDVI and land cover were constructed from the spatial datasets. Seven landslide conditioning factors such as altitude, slope angle, plan curvature, distance from drainage, soil type, distance from faults and NDVI were extracted from the spatial database. These factors were analyzed using a neuro-fuzzy model (adaptive neuro-fuzzy inference system, ANFIS) to construct the landslide susceptibility maps. During the model development works, total 5 landslide susceptibility models were obtained by using ANFIS results. For verification, the results of the analyses were then compared with the field-verified landslide locations. Additionally, the ROC curves for all landslide susceptibility models were drawn and the area under curve values was calculated. Landslide locations were used to validate results of the landslide susceptibility map and the verification results showed 98% accuracy for the model 5 employing all parameters produced in the present study as the landslide conditioning factors. The validation results showed sufficient agreement between the obtained susceptibility map and the existing data on landslide areas. Qualitatively, the model yields reasonable results which can be used for preliminary landuse planning purposes. As a conclusion, the ANFIS is a very useful tool for regional landslide susceptibility assessments.     

Advanced Oxidation of Diuron by Photo-Fenton Treatment as a Function of Operating Parameters

Advanced oxidation of diuron in aqueous solution by photo-Fenton treatment was investigated by batch experiments. Effects of operating parameters, namely, the concentrations of pesticide (diuron), hydrogen peroxide (H2O2), and ferrous ion [Fe (II)] on oxidation of diuron were investigated by using Box-Behnken statistical experiment design and the response surface methodology. Diuron oxidation by photo-Fenton treatment was evaluated by determining the total organic carbon (TOC), diuron, and adsorbable organic halogen (AOX) removals. Concentration ranges of the reagents resulting in the highest level of diuron oxidation were determined. Diuron removal increased with increasing H2O2 and Fe (II) concentrations, up to a certain level. H2O2 concentration had a more profound effect than diuron and Fe (II) on removal of diuron, TOC, and AOX from the aqueous solution. Complete (100%) disappearance of diuron was achieved after a 15?min reaction period. However, 85% of diuron was mineralized after 240?min, indicating a low level of intermediate formation. Optimal H2O2/Fe (II)/diuron ratio resulting in maximum diuron (100%), TOC (85%), and AOX (100%) removals was found to be 267/36/25?(mg?L?1).     

Electrodeposition of Si–DLC nanocomposite film and its electronic application

Microsystem Technologies - In this study, a silicon doped diamond-like carbon (DLC) nanocomposite film was deposited electrochemically and it was used to fabricate an Ag/Si–DLC/p-Si...