this study investigates the degradation of sodium dodecylbenzenesulfonate (sdbs) in aqueous solution by the fenton-like oxidation process. the effects of different parameters such as concentrations of ferric chloride and hydrogen peroxide, ph and reaction time on the sdbs removal and chemical oxygen demand (cod) reduction were evaluated. response surface methodology (rsm) with central composite...

background and objective: lactobacillus plantarum is one of the probiotics species used in functional food products. these bacteria or their purified bacteriocins are used as biological preservatives in the food industry. the first step in production of an array of probiotic products is optimizing production in fermentors. this study aimed to examine factors affecting the in vitro growth optimi...

biodegradation of phenanthrene (phe) was studied in aqueous culture to demonstrate the potential of the mixed culture in degrading high concentration of phe. the experiments were conducted to monitor biodegradation of phenanthrene for duration of 6 days. biodegradation of phe was successfully achieved in low and middle concentration by the isolated mixed culture. a full factorial central compos...

in this study, we investigated the effects of osmotic process with or without ultrasound on solid gain (sg) and water loss (wl) of cranberries. response surface methodology was used to model and determine the optimum processing conditions for wl and sg during osmotic dehydration of samples. sucrose (40-60%) and salt (0-8%) concentrations, temperature (30-50°c) and frequency of ultrasound (0-130...

based on the standards for design of structures, any structure should be designated for seismic loads and any combinations containing seismic loads. for spectral analysis of a structure, the site effect is taken into account by considering its effects on the design spectra. because of different lateral and vertical stiffness of the soil layers underneath the structure, the design spectra are di...

This paper investigates the efficiency of Ultrasonic Pulse Velocity (UPV) method in detecting cracks and flaws inside the concrete. A series of concrete beams and slab specimens were cast and damaged to simulate the different mechanisms possible in a reinforced concrete deck due to mechanical loading. Two types of simulated cracks, namely, cracks perpendicular and cracks parallel to axis of bea...

Aim To evaluate the influence of different manufacturing methods of single implant-supported metallic crowns on the internal and external marginal fit through computed microtomography. Methods Forty external hexagon implants were divided into 4 groups (n = 8), according to the manufacturing method: GC, conventional casting; GI, induction casting; GP, plasma casting; and GCAD, CAD/CAM machinin...

esterification of chitosan with adipic acid catalyzed by immobilized candida antarctica lipase b was carried out in this study. response surface methodology (rsm) based on a four-factor- five-level small central composite design (sccd) was employed to model and analyze the reaction. a total of 21 experiments representing different combinations of the four reaction parameters including ch...