The feasibility of durian tree sawdust (DTS), coconut coir (CC) and oil palm empty fruit bunch (EFB) as low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. T...The feasibility of durian tree sawdust (DTS), coconut coir (CC) and oil palm empty fruit bunch (EFB) as low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. The effects of solution pH and initial metal concentration on adsorption capacity were examined in batch experiments. The affinity and the adsorption capacity of DTS, CC and EFB were evaluated. The adsorption behaviour of Cu(II), Pb(II) and Zn(II) ions onto DTS, CC and EFB was described using Freundlich and Langmuir isotherm models. The separation factor (RL) analysis suggests that the removal of metal ions onto three agricultural wastes studied was favourable. The maximum adsorption capacities (Q) estimated from the Langmuir isotherm model for Cu(II), Pb(II) and Zn(II) were 18.42, 20.37 and 22.78 mg/g for DTS, 18.38, 37.04 and 24.39 mg/g for CC, and 26.95, 37.59 and 21.19 mg/g for EFB, respectively. The characterisation studies were carried out using Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectrometer (EDX) and Fourier Transform Infrared Spectrometer (FTIR). The surface morphology of the biosorbents changed significantly following interaction with metal ions. The primary adsorption mechanism was complexation between metal ions and binding sites of biosorbents. Both hydroxyl and amine groups are the main binding sites in DTS, CC and EFB.展开更多
Preservatives are usually added to food products to ensure longer shelf life and prevent decomposition process and microbial growth. However, synthetic food preservatives can also give negative side effect to health a...Preservatives are usually added to food products to ensure longer shelf life and prevent decomposition process and microbial growth. However, synthetic food preservatives can also give negative side effect to health and are harmful to human and animal physiology. Based on the potential of herbs and spices as antimicrobial agent, the purpose of this study is to identify antibacterial activity from extracts of some local herbs and spices: Phaeomeria speciosa (P. speciosa), Aquilaria subintegra (A. subintegra), Polygonum minus (P. minus), Syzygium aromaticum (S. aromaticum), Cinnamomum verum (C. verum) and Piper nigrum (P. nigrum) against food bacteria using disc diffusion method. Results revealed that dichloromethane extracts of C. verum, hexane extracts of S. aromaticum and P. minus showed the most active antibacterial against tested bacteria. The Minimal Inhibitory Concentrations (MIC) ranged from 25 to 75 mg/ml for dichloromethane extract of C. verum, hexane extract of S. aromaticum and P. minus. Therefore further research should be pursued to identify the chemical structure of antibacterial agents from the active extracts as an alternative source of natural preservatives.展开更多
The efficacy of coconut tree sawdust (CTS), eggshell (ES) and sugarcane bagasse (SB) as alternative low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. Batch...The efficacy of coconut tree sawdust (CTS), eggshell (ES) and sugarcane bagasse (SB) as alternative low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. Batch adsorption studies were carried out to evaluate the effects of solution pH and initial metal concentration on adsorption capacity. The optimum biosorption condition was found at pH 6.0, 0.1 g biomass dosage and at 90 min equilibrium time. The adsorption data were fitted to the Freundlich and Langmuir isotherm models. The adsorption capacity and affinity of CTS, ES and SB were evaluated. The Freundlich constant (n) and separation factor (RL) values suggest that the metal ions were favourably adsorbed onto biosorbents. The maximum adsorption capacities (Q) estimated from the Langmuir isotherm model for Cu(II), Pb(II) and Zn(II) were 3.89, 25.00 and 23.81 mg/g for CTS, 34.48, 90.90 and 35.71 mg/g for ES, and 3.65, 21.28 and 40.00 mg/g for SB, respectively. The characterisation studies were performed using Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectrometer (EDX) and Fourier Transform Infrared Spectrometer (FTIR). Interaction with metal ions led to the formation of discrete aggregates on the biosorbents surface. The metal ions bound to the active sites of the biosorbents through either electrostatic attraction or complexation mechanism.展开更多
Two phenoxyherbicide nanocomposites, namely cloprop-layered double hydroxide and cloprop-zinc- layered hydroxide nanocomposites, have been synthesized by using co-precipitation and direct reaction method. PXRD pattern...Two phenoxyherbicide nanocomposites, namely cloprop-layered double hydroxide and cloprop-zinc- layered hydroxide nanocomposites, have been synthesized by using co-precipitation and direct reaction method. PXRD pattern showed an expansion of interlayer spacing with the value of 21.0 Åand 22.7 Åfor cloprop-layered double hydroxide and cloprop-zinc-layered hydroxide nanocomposite, respectively. It is evident from FTIR and elemental analyses that both nanocomposites were successfully intercalated between the interlayers of layered metal hydroxide. Controlled release of cloprop anion from interlayer of nanocomposites for both cloprop-layered double hydroxide and cloprop-zinc-layered hydroxide nanocomposite into phosphate solution was rapid initially and slow thereafter. The percentage of accumulated release of cloprop anion from cloprop-zinc-layered hydroxide nanocomposite was slightly higher than that from cloprop-layered double hydroxide nanocomposite. Kinetic behavior of cloprop release was governed by pseudo-second-order for cloprop-layered double hydroxide nanocomposite while parabolic diffusion for cloprop-zinc-layered hydroxide nanocomposite. Results from this study highlight the potential of both nanocomposites as capsulated material for controlled release of cloprop phenoxyherbicides anion.展开更多
Objective:To characterize the major allergens of Macrobrachium rosenbergii.(giant freshwater prawn).Methods:Raw and cooked extracts of the giant freshwater prawn were prepared.The IgE reactivity pattern was identified...Objective:To characterize the major allergens of Macrobrachium rosenbergii.(giant freshwater prawn).Methods:Raw and cooked extracts of the giant freshwater prawn were prepared.The IgE reactivity pattern was identified by sodium dodecyl sulfate polyaerylamide gel electrophoresis(SDS-PAGE)and immunoblotting technique with the sera of 20 skin prick test(SPT)positive patients.The major allergen identified was then characterized using the proteomics approach involving a combination of two-dimensional(2-DE)electrophoresis,mass spectrometry and bioinformatics tools.Results:SDS-PAGE of the raw extract showed 23 protein bands(15-250 kDa)but those ranging from 40 to 100 kDa were not found in the cooked extract.From immunoblotting experiments,raw and cooked extracts demonstrated 11 and 5 IgE-binding proteins,respectively,with a molecular mass ranging from 15 to 155 kDa.A heat-resistant 36 kDa protein was identified as the major allergen of both extracts.In addition,a 42 kDa heat-sensitive protein was shown to be a major allergen of the raw extract.The 2-DE gel fractionated the prawn proteins to more than 50 different protein spots.Of these,10 spots showed specific:IgE reactivity with patients'sera.Matrix assisted laser desorption/ionization-lime of flight(MALDI-TOF)analysis led to identification of 2 important allergens,tropomyosin and arginine kinase.Conclusions:It can be concluded that the availability of such allergens would help in component-based diagnosis and therapy of prawn allergies.展开更多
Preparation of hydroxyapatite(HA)through natural sources,such as fish scales or synthetic HA produced from the chemical reaction has been widely used as biomedical materials because HA is bioactive,non-toxic and osteo...Preparation of hydroxyapatite(HA)through natural sources,such as fish scales or synthetic HA produced from the chemical reaction has been widely used as biomedical materials because HA is bioactive,non-toxic and osteoconductive with a crystallographic structure almost similar to that of the bone mineral.In addition,HAwith particle size<10 microns is classified as common inorganic filler used to improve the mechanical properties and biocompatibility of polymer composites.The purpose of this review is to collect information related to HA,and to provide readers with information about synthesis methods,advantages of hydroxyapatite as biomaterial,biomedical applications of polymer/HA composites.展开更多
Prototype of atmospheric pressure non-thermal corona plasma reactor, developed for degradation of organics in water, operates at significantly higher frequency than other reactors for that purpose, and without sparks....Prototype of atmospheric pressure non-thermal corona plasma reactor, developed for degradation of organics in water, operates at significantly higher frequency than other reactors for that purpose, and without sparks. Its construction provides the umbrella shaped, sustained pulsating corona discharge, with defined discharge oscillations on a given pulse frequency above the water surface. Dye degradation rate decreases with the decrease of discharge current density. Plasmaformed H2O2 is consumed in dye degradation. The energy yield of dye degradation is 2.45 g k Wh^-1 for 50 ppm solution, which is higher than in other publications for comparable experimental conditions.展开更多
This paper reviews the quality changes that occur towards the food products during the frozen storage period.This research aims to determine the significant physical and chemical changes that had occurred onto the fro...This paper reviews the quality changes that occur towards the food products during the frozen storage period.This research aims to determine the significant physical and chemical changes that had occurred onto the frozen foods.Indeed,refrigerated storage is the easiest way to preserve food within short handling time.Based on the observation,it was discovered that the kinetics reactions help to establish computer-aided quality,prediction models.In certain food products,the negative impact of temperature indicated the need for a thorough evaluation of the quality parameters of individual’s kinetics reaction.In general,a reasonable temperature to store food is-18°C for most frozen foods,and this will retain the quality of commercial storage.展开更多
The aims of this study were to prepare natural hydroxyapatite from fish scales(FsHAp)for potential use as a filler in polymer.The FsHAp was prepared from Tilapia fish scales using thermal method.The FsHAp was milled f...The aims of this study were to prepare natural hydroxyapatite from fish scales(FsHAp)for potential use as a filler in polymer.The FsHAp was prepared from Tilapia fish scales using thermal method.The FsHAp was milled for 48 h and dried by spray method.The morphology was characterized using field emission scanning electron microscope(FESEM)which showed irregular shape of FsHAp particles with particle size around 7μm.The analysis of FsHAp was carried out using Fourier transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD)to confirm chemical structure of FsHAp.展开更多
Detection of oil pollution in soil has been carried out using laser-induced breakdown spectroscopy（LIBS）. A pulsed neodymium-doped yttrium aluminum garnet（Nd：YAG） laser（1,064 nm, 8 ns, 200 mJ） was focused onto ...Detection of oil pollution in soil has been carried out using laser-induced breakdown spectroscopy（LIBS）. A pulsed neodymium-doped yttrium aluminum garnet（Nd：YAG） laser（1,064 nm, 8 ns, 200 mJ） was focused onto pelletized soil samples. Emission spectra were obtained from oil-contaminated soil and clean soil. The contaminated soil had almost the same spectrum profile as the clean soil and contained the same major and minor elements. However, a C–H molecular band was clearly detected in the oil-contaminated soil, while no C–H band was detected in the clean soil. Linear calibration curve of the C–H molecular band was successfully made by using a soil sample containing various concentrations of oil. The limit of detection of the C–H band in the soil sample was 0.001 mL/g. Furthermore, the emission spectrum of the contaminated soil clearly displayed titanium（Ti） lines, which were not detected in the clean soil. The existence of the C–H band and Ti lines in oil-contaminated soil can be used to clearly distinguish contaminated soil from clean soil. For comparison, the emission spectra of contaminated and clean soil were also obtained using scanning electron microscope-energy dispersive X-ray（SEM/EDX） spectroscopy,showing that the spectra obtained using LIBS are much better than using SEM/EDX, as indicated by the signal to noise ratio（S/N ratio）.展开更多
The composite systems can be non-uniquely decomposed into parts（subsystems）.Not all decompositions（structures） of a composite system are equally physically relevant.In this paper we answer on theoretical ground wh...The composite systems can be non-uniquely decomposed into parts（subsystems）.Not all decompositions（structures） of a composite system are equally physically relevant.In this paper we answer on theoretical ground why it may be so.We consider a pair of mutually un-coupled modes in the phase space representation that are subjected to the independent quantum amplitude damping channels.By investigating asymptotic dynamics of the degrees of freedom,we find that the environment is responsible for the structures non-equivalence.Only one structure is distinguished by both locality of the environmental influence on its subsystems and a classical-like description.展开更多
Objective: To investigate the effects of Aquilaria subintegra leaf aqueous extracts on the aphrodisiac properties including sexual behaviour, testosterone level, percentage of pregnancy, number of offspring and male t...Objective: To investigate the effects of Aquilaria subintegra leaf aqueous extracts on the aphrodisiac properties including sexual behaviour, testosterone level, percentage of pregnancy, number of offspring and male to female ratio of offspring in ICR mice. Methods: In this experiment, each male cohabitated with one female in a polysulfone cage. 30 ICR male mice were divided into 6 groups that received normal saline (the control group), 50 mg/kg, 100 mg/kg, 200 mg/kg, 500 mg/kg, and 1000 mg/kg body weight of Aquilaria subintegra leaf aqueous extracts orally for 21 days consecutively. Sexual behavior, percentage of pregnancy, number of offspring and male to female ratio of offspring in ICR mice were measured according to the established methods. Testosterone level was measured by using enzyme-linked immunosorbent assay. Results: Mice that received Aquilaria subintegra leaf aqueous extracts at 50 mg/kg body weight (day 0) had significantly higher mount frequency as compared to the control group;groups treated with 100, 500, 1000 mg/kg body weight extracts produced a greater number of offsprings when compared to the control group. All aphrodisiac parameters were similar between the treatment groups and the control group, indicating that Aquilaria subintegra leaf aqueous extract did not significantly alter the aphrodisiac parameters. Conclusions: Aquilaria subintegra leaf aqueous extracts have no effect on the aphrodisiac properties, but could increase the breeding rate in mice.展开更多
This paper presents the results of our investigations of breakdown mechanisms, as well as a description of their influence on the distributions of time delay distributions, for a gas tube filled with nitrogen at 4 mba...This paper presents the results of our investigations of breakdown mechanisms, as well as a description of their influence on the distributions of time delay distributions, for a gas tube filled with nitrogen at 4 mbar. The values of the time delay are measured for different voitages, and the values of the relaxation times and their distributions and probability plots are analyzed. The obtained density distributions have Gaussian distributions and exponential distributions for different values of relaxation times （Gaussian for small values and exponential for large values of relaxation time）. It is shown that for middle values of relaxation time the delay distributions have a shape between Caussian and exponential distributions, which is a result of the different influences of electrical breakdown.展开更多
In this paper, the boundary layer stagnation-point slip flow and heat transfer towards a shrinking/stretching cylinder over a permeable surface is considered. The governing equations are first transformed into a syste...In this paper, the boundary layer stagnation-point slip flow and heat transfer towards a shrinking/stretching cylinder over a permeable surface is considered. The governing equations are first transformed into a system of non-dimensional equations via the non-dimensional variables, and then into self-similar ordinary differential equations before they are solved numerically using the shooting method. Numerical results are obtained for the skin friction coefficient and the local Nusselt number as well as the velocity and temperature profiles for some values of the governing parameters, namely the velocity slip parameter (α), the thermal slip parameter (β), the curvature parameter (γ) and the velocity ratio parameter (c/a). The physical quantities of interest are the skin friction coefficient and the local Nusselt number measured by f’’(0) and –θ’(0), respectively. The numerical results show that the velocity slip parameter α increases the heat transfer rate at the surface, while the thermal slip parameter β decreases it. On the other hand, increasing the velocity slip parameter α causes the decrease in the flow velocity. Further, it is found that the solutions for a shrinking cylinder (c/ac/a>0) case. Finally, it is also found that the values of f’’(0) and –θ’(0) increase as the curvature parameter γ increases.展开更多
The purpose of this research is to investigate the effciency of explicit diagonally implicit multi-stage integration methods with extrapolation. The author gave detailed explanation of explicit diagonally implicit mul...The purpose of this research is to investigate the effciency of explicit diagonally implicit multi-stage integration methods with extrapolation. The author gave detailed explanation of explicit diagonally implicit multi-stage integration method and compared the base method with a technique known as extrapolation to improve the effciency. Extrapolation for symmetric Runge-Kutta method is proven to improve the accuracy since with extrapolation the solutions exhibit asymptotic error expansion, however for General linear methods, it is not known whether extrapolation can improve the effciency or not. Therefore this research focuses on the numerical experimental results of the explicit diagonally implicit multistage integration with and without extrapolation for solving some ordinary differential equations. The numerical results showed that the base method with extrapolation is more effcient than the method without extrapolation.展开更多
We determine the encapsulation of a chloroform molecule into a D,L-Ala cyclopeptide nanotube by investigating the interaction energy between the two molecular structures. We employ the Lennard-Jones potential and a co...We determine the encapsulation of a chloroform molecule into a D,L-Ala cyclopeptide nanotube by investigating the interaction energy between the two molecular structures. We employ the Lennard-Jones potential and a continuum approach which assumes that the atoms are evenly distributed over the molecules providing average atomic densities. Our result demonstrates that the encapsulation depends on the size of the molecule and the internal diameter of the peptide nantube. In particular, the on-axis chloroform molecule is only accepted into a peptide nanotube whose internal radius is greater than 5 ?. If located near the edge of the nanotube, then it is unlikely that the chloroform molecule will enter the nanotube. This is due to the energy valley that the molecule will need to overcome to move past the edge into the open end of the nanotube.展开更多
The extrapolation technique has been proved to be very powerful in improving the performance of the approximate methods by large time whether engineering or scientific problems that are handled on computers. In this p...The extrapolation technique has been proved to be very powerful in improving the performance of the approximate methods by large time whether engineering or scientific problems that are handled on computers. In this paper, we investigate the efficiency of extrapolation of explicit general linear methods with Inherent Runge-Kutta stability in solving the non-stiff problems. The numerical experiments are shown for Van der Pol and Brusselator test problems to determine the efficiency of the explicit general linear methods with extrapolation technique. The numerical results showed that method with extrapolation is efficient than method without extrapolation.展开更多
The rotation of a ship’s propeller can accelerate the water flow around it,which puts pressure on seabed particles.Continuous pressure on the seabed can significantly trigger erosion and sedimentation of coastal wate...The rotation of a ship’s propeller can accelerate the water flow around it,which puts pressure on seabed particles.Continuous pressure on the seabed can significantly trigger erosion and sedimentation of coastal waters.Considering the impact that can be caused,the ship’s propeller rotation limit needs to be determined to avoid damage to the aquatic ecosystem.This research determines the threshold of ship propeller rotation based on the water flow velocity characteristic.Research has been carried out at the Hydrodynamics Laboratory on several variations of propeller rotation R_(rmp)(r/min)and water depth using empirical approaches,numerical simulations,and scale model experiments.Analysis based on general standard criteria for erosion and sedimentation shows that a propeller with a diameter(D_(p))of 1.5 m is safe for propeller rotation at 25 r/min at all water depths.Then,the propeller rotation of 75 r/min is safe for a distance between the propeller axis and the bottom of the water equal to D_(p).Meanwhile,rotation at 120 r/min is safe at a minimum distance of 1.5 D_(p),and 230 r/min is safe for a minimum distance of 2.0 D_(p).The propeller rotation threshold criteria are essential to determining the new under-keel clearance for environmentally friendly ship operations.Threshold values vary based on seabed particle type and water depth.展开更多
Backward doubly stochastic integral equations of the Volterra type(BDSIEVs in short)are observed in this paper.Existence of M-solution established under functional Lipschitz assumptions.Duality principle between linea...Backward doubly stochastic integral equations of the Volterra type(BDSIEVs in short)are observed in this paper.Existence of M-solution established under functional Lipschitz assumptions.Duality principle between linearBDSIEVs and(forward)stochastic Volterra integral equations is obtained.Using duality principle,the comparison theorem for the adapted solutions of BDSIEVs is proven.展开更多
文摘The feasibility of durian tree sawdust (DTS), coconut coir (CC) and oil palm empty fruit bunch (EFB) as low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. The effects of solution pH and initial metal concentration on adsorption capacity were examined in batch experiments. The affinity and the adsorption capacity of DTS, CC and EFB were evaluated. The adsorption behaviour of Cu(II), Pb(II) and Zn(II) ions onto DTS, CC and EFB was described using Freundlich and Langmuir isotherm models. The separation factor (RL) analysis suggests that the removal of metal ions onto three agricultural wastes studied was favourable. The maximum adsorption capacities (Q) estimated from the Langmuir isotherm model for Cu(II), Pb(II) and Zn(II) were 18.42, 20.37 and 22.78 mg/g for DTS, 18.38, 37.04 and 24.39 mg/g for CC, and 26.95, 37.59 and 21.19 mg/g for EFB, respectively. The characterisation studies were carried out using Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectrometer (EDX) and Fourier Transform Infrared Spectrometer (FTIR). The surface morphology of the biosorbents changed significantly following interaction with metal ions. The primary adsorption mechanism was complexation between metal ions and binding sites of biosorbents. Both hydroxyl and amine groups are the main binding sites in DTS, CC and EFB.
文摘Preservatives are usually added to food products to ensure longer shelf life and prevent decomposition process and microbial growth. However, synthetic food preservatives can also give negative side effect to health and are harmful to human and animal physiology. Based on the potential of herbs and spices as antimicrobial agent, the purpose of this study is to identify antibacterial activity from extracts of some local herbs and spices: Phaeomeria speciosa (P. speciosa), Aquilaria subintegra (A. subintegra), Polygonum minus (P. minus), Syzygium aromaticum (S. aromaticum), Cinnamomum verum (C. verum) and Piper nigrum (P. nigrum) against food bacteria using disc diffusion method. Results revealed that dichloromethane extracts of C. verum, hexane extracts of S. aromaticum and P. minus showed the most active antibacterial against tested bacteria. The Minimal Inhibitory Concentrations (MIC) ranged from 25 to 75 mg/ml for dichloromethane extract of C. verum, hexane extract of S. aromaticum and P. minus. Therefore further research should be pursued to identify the chemical structure of antibacterial agents from the active extracts as an alternative source of natural preservatives.
文摘The efficacy of coconut tree sawdust (CTS), eggshell (ES) and sugarcane bagasse (SB) as alternative low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. Batch adsorption studies were carried out to evaluate the effects of solution pH and initial metal concentration on adsorption capacity. The optimum biosorption condition was found at pH 6.0, 0.1 g biomass dosage and at 90 min equilibrium time. The adsorption data were fitted to the Freundlich and Langmuir isotherm models. The adsorption capacity and affinity of CTS, ES and SB were evaluated. The Freundlich constant (n) and separation factor (RL) values suggest that the metal ions were favourably adsorbed onto biosorbents. The maximum adsorption capacities (Q) estimated from the Langmuir isotherm model for Cu(II), Pb(II) and Zn(II) were 3.89, 25.00 and 23.81 mg/g for CTS, 34.48, 90.90 and 35.71 mg/g for ES, and 3.65, 21.28 and 40.00 mg/g for SB, respectively. The characterisation studies were performed using Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectrometer (EDX) and Fourier Transform Infrared Spectrometer (FTIR). Interaction with metal ions led to the formation of discrete aggregates on the biosorbents surface. The metal ions bound to the active sites of the biosorbents through either electrostatic attraction or complexation mechanism.
文摘Two phenoxyherbicide nanocomposites, namely cloprop-layered double hydroxide and cloprop-zinc- layered hydroxide nanocomposites, have been synthesized by using co-precipitation and direct reaction method. PXRD pattern showed an expansion of interlayer spacing with the value of 21.0 Åand 22.7 Åfor cloprop-layered double hydroxide and cloprop-zinc-layered hydroxide nanocomposite, respectively. It is evident from FTIR and elemental analyses that both nanocomposites were successfully intercalated between the interlayers of layered metal hydroxide. Controlled release of cloprop anion from interlayer of nanocomposites for both cloprop-layered double hydroxide and cloprop-zinc-layered hydroxide nanocomposite into phosphate solution was rapid initially and slow thereafter. The percentage of accumulated release of cloprop anion from cloprop-zinc-layered hydroxide nanocomposite was slightly higher than that from cloprop-layered double hydroxide nanocomposite. Kinetic behavior of cloprop release was governed by pseudo-second-order for cloprop-layered double hydroxide nanocomposite while parabolic diffusion for cloprop-zinc-layered hydroxide nanocomposite. Results from this study highlight the potential of both nanocomposites as capsulated material for controlled release of cloprop phenoxyherbicides anion.
基金Supported by a research grant from UPSI(grant No.UPSI2011-0018-102-01)
文摘Objective:To characterize the major allergens of Macrobrachium rosenbergii.(giant freshwater prawn).Methods:Raw and cooked extracts of the giant freshwater prawn were prepared.The IgE reactivity pattern was identified by sodium dodecyl sulfate polyaerylamide gel electrophoresis(SDS-PAGE)and immunoblotting technique with the sera of 20 skin prick test(SPT)positive patients.The major allergen identified was then characterized using the proteomics approach involving a combination of two-dimensional(2-DE)electrophoresis,mass spectrometry and bioinformatics tools.Results:SDS-PAGE of the raw extract showed 23 protein bands(15-250 kDa)but those ranging from 40 to 100 kDa were not found in the cooked extract.From immunoblotting experiments,raw and cooked extracts demonstrated 11 and 5 IgE-binding proteins,respectively,with a molecular mass ranging from 15 to 155 kDa.A heat-resistant 36 kDa protein was identified as the major allergen of both extracts.In addition,a 42 kDa heat-sensitive protein was shown to be a major allergen of the raw extract.The 2-DE gel fractionated the prawn proteins to more than 50 different protein spots.Of these,10 spots showed specific:IgE reactivity with patients'sera.Matrix assisted laser desorption/ionization-lime of flight(MALDI-TOF)analysis led to identification of 2 important allergens,tropomyosin and arginine kinase.Conclusions:It can be concluded that the availability of such allergens would help in component-based diagnosis and therapy of prawn allergies.
文摘Preparation of hydroxyapatite(HA)through natural sources,such as fish scales or synthetic HA produced from the chemical reaction has been widely used as biomedical materials because HA is bioactive,non-toxic and osteoconductive with a crystallographic structure almost similar to that of the bone mineral.In addition,HAwith particle size<10 microns is classified as common inorganic filler used to improve the mechanical properties and biocompatibility of polymer composites.The purpose of this review is to collect information related to HA,and to provide readers with information about synthesis methods,advantages of hydroxyapatite as biomaterial,biomedical applications of polymer/HA composites.
基金the Ministry of Education and Science of Serbia for supporting this work(Grant TR 34008 and No.Ⅲ43011)
文摘Prototype of atmospheric pressure non-thermal corona plasma reactor, developed for degradation of organics in water, operates at significantly higher frequency than other reactors for that purpose, and without sparks. Its construction provides the umbrella shaped, sustained pulsating corona discharge, with defined discharge oscillations on a given pulse frequency above the water surface. Dye degradation rate decreases with the decrease of discharge current density. Plasmaformed H2O2 is consumed in dye degradation. The energy yield of dye degradation is 2.45 g k Wh^-1 for 50 ppm solution, which is higher than in other publications for comparable experimental conditions.
文摘This paper reviews the quality changes that occur towards the food products during the frozen storage period.This research aims to determine the significant physical and chemical changes that had occurred onto the frozen foods.Indeed,refrigerated storage is the easiest way to preserve food within short handling time.Based on the observation,it was discovered that the kinetics reactions help to establish computer-aided quality,prediction models.In certain food products,the negative impact of temperature indicated the need for a thorough evaluation of the quality parameters of individual’s kinetics reaction.In general,a reasonable temperature to store food is-18°C for most frozen foods,and this will retain the quality of commercial storage.
文摘The aims of this study were to prepare natural hydroxyapatite from fish scales(FsHAp)for potential use as a filler in polymer.The FsHAp was prepared from Tilapia fish scales using thermal method.The FsHAp was milled for 48 h and dried by spray method.The morphology was characterized using field emission scanning electron microscope(FESEM)which showed irregular shape of FsHAp particles with particle size around 7μm.The analysis of FsHAp was carried out using Fourier transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD)to confirm chemical structure of FsHAp.
基金financially supported by Diponegoro University,Semarang,Indonesia (31419/UN7.5.1/PG/2015 and 573-18/UN7.5.1/PG/2016)
文摘Detection of oil pollution in soil has been carried out using laser-induced breakdown spectroscopy（LIBS）. A pulsed neodymium-doped yttrium aluminum garnet（Nd：YAG） laser（1,064 nm, 8 ns, 200 mJ） was focused onto pelletized soil samples. Emission spectra were obtained from oil-contaminated soil and clean soil. The contaminated soil had almost the same spectrum profile as the clean soil and contained the same major and minor elements. However, a C–H molecular band was clearly detected in the oil-contaminated soil, while no C–H band was detected in the clean soil. Linear calibration curve of the C–H molecular band was successfully made by using a soil sample containing various concentrations of oil. The limit of detection of the C–H band in the soil sample was 0.001 mL/g. Furthermore, the emission spectrum of the contaminated soil clearly displayed titanium（Ti） lines, which were not detected in the clean soil. The existence of the C–H band and Ti lines in oil-contaminated soil can be used to clearly distinguish contaminated soil from clean soil. For comparison, the emission spectra of contaminated and clean soil were also obtained using scanning electron microscope-energy dispersive X-ray（SEM/EDX） spectroscopy,showing that the spectra obtained using LIBS are much better than using SEM/EDX, as indicated by the signal to noise ratio（S/N ratio）.
基金Project financially supported by the Ministry of Science Serbia (Grant No. 171028)
文摘The composite systems can be non-uniquely decomposed into parts（subsystems）.Not all decompositions（structures） of a composite system are equally physically relevant.In this paper we answer on theoretical ground why it may be so.We consider a pair of mutually un-coupled modes in the phase space representation that are subjected to the independent quantum amplitude damping channels.By investigating asymptotic dynamics of the degrees of freedom,we find that the environment is responsible for the structures non-equivalence.Only one structure is distinguished by both locality of the environmental influence on its subsystems and a classical-like description.
文摘Objective: To investigate the effects of Aquilaria subintegra leaf aqueous extracts on the aphrodisiac properties including sexual behaviour, testosterone level, percentage of pregnancy, number of offspring and male to female ratio of offspring in ICR mice. Methods: In this experiment, each male cohabitated with one female in a polysulfone cage. 30 ICR male mice were divided into 6 groups that received normal saline (the control group), 50 mg/kg, 100 mg/kg, 200 mg/kg, 500 mg/kg, and 1000 mg/kg body weight of Aquilaria subintegra leaf aqueous extracts orally for 21 days consecutively. Sexual behavior, percentage of pregnancy, number of offspring and male to female ratio of offspring in ICR mice were measured according to the established methods. Testosterone level was measured by using enzyme-linked immunosorbent assay. Results: Mice that received Aquilaria subintegra leaf aqueous extracts at 50 mg/kg body weight (day 0) had significantly higher mount frequency as compared to the control group;groups treated with 100, 500, 1000 mg/kg body weight extracts produced a greater number of offsprings when compared to the control group. All aphrodisiac parameters were similar between the treatment groups and the control group, indicating that Aquilaria subintegra leaf aqueous extract did not significantly alter the aphrodisiac parameters. Conclusions: Aquilaria subintegra leaf aqueous extracts have no effect on the aphrodisiac properties, but could increase the breeding rate in mice.
基金supported by the Ministry of Education and Science of the Republic of Serbia (Project 43011 and Project 43012)
文摘This paper presents the results of our investigations of breakdown mechanisms, as well as a description of their influence on the distributions of time delay distributions, for a gas tube filled with nitrogen at 4 mbar. The values of the time delay are measured for different voitages, and the values of the relaxation times and their distributions and probability plots are analyzed. The obtained density distributions have Gaussian distributions and exponential distributions for different values of relaxation times （Gaussian for small values and exponential for large values of relaxation time）. It is shown that for middle values of relaxation time the delay distributions have a shape between Caussian and exponential distributions, which is a result of the different influences of electrical breakdown.
文摘In this paper, the boundary layer stagnation-point slip flow and heat transfer towards a shrinking/stretching cylinder over a permeable surface is considered. The governing equations are first transformed into a system of non-dimensional equations via the non-dimensional variables, and then into self-similar ordinary differential equations before they are solved numerically using the shooting method. Numerical results are obtained for the skin friction coefficient and the local Nusselt number as well as the velocity and temperature profiles for some values of the governing parameters, namely the velocity slip parameter (α), the thermal slip parameter (β), the curvature parameter (γ) and the velocity ratio parameter (c/a). The physical quantities of interest are the skin friction coefficient and the local Nusselt number measured by f’’(0) and –θ’(0), respectively. The numerical results show that the velocity slip parameter α increases the heat transfer rate at the surface, while the thermal slip parameter β decreases it. On the other hand, increasing the velocity slip parameter α causes the decrease in the flow velocity. Further, it is found that the solutions for a shrinking cylinder (c/ac/a>0) case. Finally, it is also found that the values of f’’(0) and –θ’(0) increase as the curvature parameter γ increases.
文摘The purpose of this research is to investigate the effciency of explicit diagonally implicit multi-stage integration methods with extrapolation. The author gave detailed explanation of explicit diagonally implicit multi-stage integration method and compared the base method with a technique known as extrapolation to improve the effciency. Extrapolation for symmetric Runge-Kutta method is proven to improve the accuracy since with extrapolation the solutions exhibit asymptotic error expansion, however for General linear methods, it is not known whether extrapolation can improve the effciency or not. Therefore this research focuses on the numerical experimental results of the explicit diagonally implicit multistage integration with and without extrapolation for solving some ordinary differential equations. The numerical results showed that the base method with extrapolation is more effcient than the method without extrapolation.
文摘We determine the encapsulation of a chloroform molecule into a D,L-Ala cyclopeptide nanotube by investigating the interaction energy between the two molecular structures. We employ the Lennard-Jones potential and a continuum approach which assumes that the atoms are evenly distributed over the molecules providing average atomic densities. Our result demonstrates that the encapsulation depends on the size of the molecule and the internal diameter of the peptide nantube. In particular, the on-axis chloroform molecule is only accepted into a peptide nanotube whose internal radius is greater than 5 ?. If located near the edge of the nanotube, then it is unlikely that the chloroform molecule will enter the nanotube. This is due to the energy valley that the molecule will need to overcome to move past the edge into the open end of the nanotube.
文摘The extrapolation technique has been proved to be very powerful in improving the performance of the approximate methods by large time whether engineering or scientific problems that are handled on computers. In this paper, we investigate the efficiency of extrapolation of explicit general linear methods with Inherent Runge-Kutta stability in solving the non-stiff problems. The numerical experiments are shown for Van der Pol and Brusselator test problems to determine the efficiency of the explicit general linear methods with extrapolation technique. The numerical results showed that method with extrapolation is efficient than method without extrapolation.
文摘The rotation of a ship’s propeller can accelerate the water flow around it,which puts pressure on seabed particles.Continuous pressure on the seabed can significantly trigger erosion and sedimentation of coastal waters.Considering the impact that can be caused,the ship’s propeller rotation limit needs to be determined to avoid damage to the aquatic ecosystem.This research determines the threshold of ship propeller rotation based on the water flow velocity characteristic.Research has been carried out at the Hydrodynamics Laboratory on several variations of propeller rotation R_(rmp)(r/min)and water depth using empirical approaches,numerical simulations,and scale model experiments.Analysis based on general standard criteria for erosion and sedimentation shows that a propeller with a diameter(D_(p))of 1.5 m is safe for propeller rotation at 25 r/min at all water depths.Then,the propeller rotation of 75 r/min is safe for a distance between the propeller axis and the bottom of the water equal to D_(p).Meanwhile,rotation at 120 r/min is safe at a minimum distance of 1.5 D_(p),and 230 r/min is safe for a minimum distance of 2.0 D_(p).The propeller rotation threshold criteria are essential to determining the new under-keel clearance for environmentally friendly ship operations.Threshold values vary based on seabed particle type and water depth.
基金Grant STORM-Stochastics for Time-Space Risk ModelsResearch Council of Norway - Independent projects: ToppForsk. Project nr. 274410.
文摘Backward doubly stochastic integral equations of the Volterra type(BDSIEVs in short)are observed in this paper.Existence of M-solution established under functional Lipschitz assumptions.Duality principle between linearBDSIEVs and(forward)stochastic Volterra integral equations is obtained.Using duality principle,the comparison theorem for the adapted solutions of BDSIEVs is proven.
