The capability of rosemary extract in preventing oxidation of fish lipid

The effects of rosemary extract at different levels (%1, R1, and %2, R2) on the quality of vacuum‐packed sardine in terms of sensory, biochemical (thiobarbituric acid, total volatile basic nitrogen, peroxide value and free fatty acids) and microbiological analyses (total viable counts) were investigated. Fish were filleted and divided into three groups. First group was used as the control (C) without rosemary extract, second group was treated with 1% rosemary extracts (10 g L^?1) for 2 min (R1), and the third was treated with 2% rosemary extracts (20 g L^?1) for 2 min (R2). Thirty fillets per litre were used. After that, all groups were vacuum‐packed in polyethylene bags. The samples were stored in the refrigerator condition (4 ± 1 °C) over the storage period of 20 days. The results showed that the use of rosemary extract improved the sensory quality of both raw and cooked sardine, most preferably sardine treated with 1% of rosemary. Biochemical analysis showed that the use of 2% of rosemary extract were found to be most effective (P < 0.05) in controlling the rate of lipid oxidation.     

Effect of industrial juice concentrate processing on phenolic profile and antioxidant capacity of black carrots

Black carrot concentrate has gained increasing interest in recent years as a natural colourant due to its substantial content of bioactive compounds, especially anthocyanins. Black carrot concentrate production includes several steps, some of which are milling, mashing, pressing, pasteurisation and concentration. In this study, every step of black carrot concentrate processing was investigated to elucidate both the quantitative and qualitative changes in antioxidative compounds using spectrophotometric, HPLC‐based and LC‐QTOF‐MS‐based analyses. The results obtained indicated that processing the raw black carrot material into its concentrate led to an overall reduction of 70%, 73% and 44% in total phenolic, total flavonoid and total monomeric anthocyanin contents on a dry weight basis, respectively. Moreover, concentrate processing resulted in 67% and 71% decreases in total antioxidant capacity, determined using DPPH and CUPRAC methods, respectively, on dry weight basis. Untargeted LC‐MS‐based metabolomics analysis enabled the identification of ten phenolic components including seven anthocyanins and three phenolic acids. HPLC‐based quantification of individual anthocyanins revealed cyanidin‐3‐xylosyl (feruloylglucosyl)galactoside as the major anthocyanin component.     

Developing of N‐(4‐methylpyrimidine‐2‐yl)methacrylamide Langmuir–Blodgett thin film chemical sensor via quartz crystal microbalance technique

In the present work, the characterization and gas sensing properties of newly synthesized N‐(4‐methylpyrimidine‐2‐yl)methacrylamide ( N‐MPMA ) monomer Langmuir–Blodgett (LB) thin films were investigated. The UV–visible spectroscopy, quartz crystal microbalance (QCM), and atomic force microscopy were utilized to characterize N‐MPMA LB thin films. The surface behavior of N‐MPMA monolayer was stable and allowed an effective transfer at a surface pressure of 14 mN/m. The mass change/unit area value of the N‐MPMA LB thin film deposited quartz crystal surfaces was investigated. The amount of N‐MPMA LB thin film deposited on the substrate for bilayer was calculated as 228.72 ng (86.31 ng/mm²) and 12.5 Hz frequency shift was observed for each layer of the N‐MPMA film. The kinetic responses of N‐MPMA LB film against chloroform, dichloromethane, benzene, and toluene were measured via QCM system at room temperature. N‐MPMA QCM sensor results displayed that chloroform has the largest frequency shifts compared with the other vapors used in the present work and these results can be illuminating in terms of physical properties of organic vapors.     

A dimensionless analysis of heat and mass transport in an adsorber with thin fins; uniform pressure approach

A numerical study on heat and mass transfer in an annular adsorbent bed assisted with radial fins for an isobaric adsorption process is performed. A uniform pressure approach is employed to determine the changes of temperature and adsorbate concentration profiles in the adsorbent bed. The governing equations which are heat transfer equation for the adsorbent bed, mass balance equation for the adsorbent particle, and conduction heat transfer equation for the thin fin are non-dimensionalized in order to reduce number of governing parameters. The number of governing parameters is reduced to four as Kutateladze number, thermal diffusivity ratio, dimensionless fin coefficient and dimensionless parameter of Γ which compares mass diffusion in the adsorbent particle to heat transfer through the adsorbent bed. Temperature and adsorbate concentration contours are plotted for different values of defined dimensionless parameters to discuss heat and mass transfer rate in the bed. The average dimensionless temperature and average adsorbate concentration throughout the adsorption process are also presented to compare heat and mass transfer rate of different cases. The values of dimensionless fin coefficient, Γ number and thermal diffusivity ratio are changed from 0.01 to 100, 1 to 10^− 5 and 0.01 to 100, respectively; while the values of Kutateladze number are 1 and 100. The obtained results revealed that heat transfer rate in an adsorbent bed can be enhanced by the fin when the values of thermal diffusivity ratio and fin coefficient are low (i.e., α^? = 0.01, Λ = 0.01). Furthermore, the use of fin in an adsorbent bed with low values of Γ number (i.e. Γ = 10^− 5) does not increase heat transfer rate, significantly.     

Treatment of originally coloured wools with garlic stem extracts and zinc chloride to ensure anti‐bacterial properties with limited colour changes

In this study, the objective was to ensure anti‐bacterial properties for originally coloured wools with naturally sourced garlic stem extracts. In addition, zinc chloride‐based treatment was also carried out. The aim was to retain the original colours of the wool fibres during these treatments. The effects of both treatments were evaluated in terms of colour changes in the wool fibres. It was found that the colour changes caused by the treatments were high in white/ecru fibres but more limited in black fibres. The colour differences between the treated and untreated black fibres were near 1; they were also quite high in white/ecru fibres. The anti‐bacterial properties of the treated wool fibres against two bacteria species, one gram‐negative and one gram‐positive, were also investigated. It was observed that zinc chloride‐based treatment ensured significant anti‐bacterial efficiencies against the bacteria tested and 99.9% bacterial reduction in all cases. However, the anti‐bacterial effects of garlic stem extract‐based treated wool fibres were limited. It was observed that treatment of wool fibres with garlic stem extracts resulted in no anti‐bacterial efficiency against Escherichia coli but did provide some anti‐bacterial capability against Staphylococcus aureus. The highest bacterial reduction of S. aureus was 80.7% in originally brown‐coloured wool fibre.     

Neutronic limits in infinite target mediums driven by high energetic protons

This study presents the neutronic behavior of integral data in an infinite target medium driven by an isotropic point source of 1000 MeV incident proton. Lead–bismuth eutectic, mercury, tungsten, uranium, thorium, chromium, copper and beryllium are considered as the target material because of their favorable spallation-neutron production characteristics. Furthermore, the calculations are performed for also dual mixture of some of them. In order to be able to simulate the infinite target medium by eliminating the spatial dependence, a spherical target is considered, and its radius is increased gradually up to adequate radius ensuring the infinite target medium. In this way, the radius value ensuring the maximum neutron leakage out of the target would be determined. Numerical calculations were performed with the high-energy Monte Carlo code MCNPX in coupled neutron and proton mode using the LA150 library. The mixing of the LBE with a solid target material (such as W, U and Th) lowers significantly the target radius ensuring the maximum neutron leakage.     

Graft copolymerization of acrylic acid onto cellulose: Effects of pretreatments and crosslinking agent

The graft copolymerization of acrylic acid (AA) and 2‐acrylamido 2‐methylpropane sulfonic acid (AASO₃H) onto cellulose, in the presence or absence of crosslinking agent N,N′‐methylene bisacrylamide (NMBA), by using different concentrations of ceric ammonium nitrate (CAN) initiator in aqueous nitric acid solution at either 5 or 30°C was investigated. To investigate the effect of pretreatment of cellulose on the copolymerization, before some grafting reactions cellulose was pretreated with either 2 or 20 wt % NaOH solutions or heated in distilled water/aqueous nitric acid (2.5 × 10^?3 M) at 55°C. To determine how the excess of initiator affects the grafting and homopolymerization, separate reactions were carried out by removing the excess of ceric ions by filtration of the mixture of initiator solution and cellulose before the monomer addition. Extraction‐purified products were characterized by grafting percentage and equilibrium swelling capacity. Pretreatment of cellulose with NaOH solutions decreased the grafting percentage of copolymers. In the case of AA–AASO₃H mixtures, nonpretreated cellulose gave a higher grafting percentage than NaOH‐pretreated cellulose. Filtration also lowered the grafting of AA on the cellulose in the cases of pretreatment with either water or nitric acid. Copolymers with the highest grafting percentage (64.8%) and equilibrium swelling value (105 g H₂O/g copolymer) were obtained in grafting reactions carried out in the presence of NMBA at 5°C. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2267–2272, 2001     

A low,particle‐sized,nonporous support for enzyme immobilization: Uniform poly(glycidyl methacrylate) latex particles

The uniform and nonporous poly(glycidyl methacrylate) (poly(GMA)) latex particles, 1.7 μm in size, were first tried as a support in enzyme immobilization. For this purpose, α‐chymotrypsin (CT) was selected as the model enzyme. The low particle size and nonporous character of the selected support allowed to carry out the enzyme–subtrate interaction on a sufficiently large surface area (3.36 m²/g) and in the absence of intraparticular diffusion limitations. This property is particularly important when the immobilized CT is used for the substrates with high molecular weights (i.e., proteins). The latex particles were synthesized by dispersion polymerization of GMA. The reactive character of poly(GMA) allowed the direct attachment of primary amine groups onto the particles. Confocal laser scanning microscopy (CLSM) showed that primary amine groups were preferentially located on the particle's surface. Hence, the selected enzyme, CT was immobilized on the surface of nonporous particles via glutaraldehyde activation. For CT‐immobilized poly(GMA) particles, the maximum activity (r_m) and Michealis constant (K_m) were found to be 17.2 μmol/mg CT min and 121.6 μm, respectively. No significant loss was observed in the activity of immobilized CT, during the course of experiments. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 818–824, 2006     

RP-HPLC optimization of econea by using artificial neural networks and its antifouling performance on the Turkish coastline

Coverage of artificial surfaces within seawater by fouling organisms is defined as biofouling. Although biofouling is a natural process, it has some disadvantages for shipping industry such as increased fuel consumption, and CO₂ emission. Therefore, the ships' hull must be covered by antifouling (AF) or fouling release type coatings to overcome biofouling. In general, the so-called self-polishing AF paints contain biocides for preventing fouling organisms. Their concentrations and release rates from AF coatings are of great importance and they definitely affect both quality and cost of the coating. In the present study, we aimed at applying a new robust method. In this method, we used a model biocide, i.e., econea, to obtain its RP-HPLC optimization through artificial neural networks (ANN) and to see its antifouling performance. Column temperature, mobile phase ratio, flow rate, concentration and wavelength as input parameters and retention time as an output parameter were used in the ANN modeling. In conclusion, the R&D groups in AF paint industry may use RP-HPLC method supported with ANN modeling in further studies.