The Experts below are selected from a list of 4233 Experts worldwide ranked by ideXlab platform
Pitt Supaphol - One of the best experts on this subject based on the ideXlab platform.
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morphology release characteristics and antimicrobial effect of nisin loaded electroSpun gelatin Fiber mat
Journal of Food Protection, 2009Co-Authors: Chanuttaporn Dheraprasart, Pitt Supaphol, Sirirat Rengpipat, Jirarat TattiyakulAbstract:Gelatin electroSpun (e-Spun) Fiber mats containing nisin were produced by electrostatic spinning of gelatin-nisin in 70% (vol/vol) acetic acid aqueous solutions. Varying nisin loading concentration (0 to 3% [wt/wt]) did not affect the Fiber average diameter, whereas increasing gelatin concentration from 20 to 24% (wt/vol) caused an increase in the average diameter. All nisin-loaded gelatin e-Spun Fiber mats demonstrated inhibition against Lactobacillus plantarum TISTR 850. However, all Fiber mats were fragile and easily dissolved in water. Cross-linking by saturated glutaraldehyde vapor at 37°C for 5 min was done to strengthen the mat. Tensile strength, Young's modulus, and elongation of the cross-linked gelatin-nisin e-Spun Fiber mats varied in the range of 2.6 to 20.3 MPa, 163 to 966 MPa, and 1.7 to 5.9%, respectively. Cross-linking did not affect the mat's inhibition activity against L. plantarum TISTR 850. Nisin retention in cross-linked antimicrobial gelatin e-Spun Fiber mats was in the range of 1.0 ...
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vitamin loaded electroSpun cellulose acetate nanoFiber mats as transdermal and dermal therapeutic agents of vitamin a acid and vitamin e
European Journal of Pharmaceutics and Biopharmaceutics, 2007Co-Authors: Pattama Taepaiboon, Uracha Rungsardthong, Pitt SupapholAbstract:Abstract The present contribution reports the use of mats of electroSpun cellulose acetate (CA; acetyl content = 39.8%; M w = 30,000 Da) nanoFibers as carriers for delivery of the model vitamins, all-trans retinoic acid or vitamin A acid (Retin-A) and α-tocopherol or vitamin E (Vit-E). The amounts of Vit-E and Retin-A loaded in the base CA solution [17% w/v in 2:1 v/v acetone/ N , N -dimethylacetamide (DMAc)] were 5 and 0.5 wt% (based on the weight of CA), respectively. Cross-sectionally round and smooth Fibers were obtained. The average diameters of these Fibers ranged between 247 and 265 nm. The total immersion of the vitamin-loaded as-Spun CA Fiber mats in the acetate buffer solutions containing either 0.5 vol % Tween 80 or 0.5 vol % Tween 80 and 10 vol % methanol was used to arrive at the cumulative release of the vitamins from the Fiber mat samples. The same was also conducted on the vitamin-loaded solution-cast CA films for comparison. In most cases, the vitamin-loaded as-Spun Fiber mats exhibited a gradual and monotonous increase in the cumulative release of the vitamins over the test periods (i.e., 24 h for Vit-E-loaded samples and 6 h for Retin-A-loaded ones), while the corresponding as-cast films exhibited a burst release of the vitamins.
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osteoblastic phenotype expression of mc3t3 e1 cultured on electroSpun polycaprolactone Fiber mats filled with hydroxyapatite nanoparticles
Biomacromolecules, 2007Co-Authors: Patcharaporn Wutticharoenmongkol, Prasit Pavasant, Pitt SupapholAbstract:ElectroSpun (e-Spun) Fiber mats of polycaprolactone (PCL; Mn = 80 000 g mol-1) with or without the presence of hydroxyapatite (HAp) nanoparticles (at 1% w/v based on the volume of the PCL solution) were successfully fabricated. The potential for use of these e-Spun Fiber mats as bone scaffolds was assessed by mouse calvaria-derived pre-osteoblastic cells, MC3T3-E1, in terms of attachment, proliferation, differentiation, and mineralization. Despite the lower number of cells attached at early time points, both the fibrous scaffolds supported the proliferation of MC3T3-E1 at similar levels to tissue-culture polystyrene plate (TCPS), with the cells growing on the PCL/HAp Fiber mat (i.e., PCL/HAp-FS) showing the greatest proliferation rate on day 3 after the initial attachment period of 16 h. Alkaline phosphatase (ALP) activity of the cells grown on TCPS was the greatest on day 3 after cell culturing, while that of the cells grown on PCL/HAp-FS reached a maximum on day 5. On the other hand, the ALP activity of...
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bone scaffolds from electroSpun Fiber mats of poly 3 hydroxybutyrate poly 3 hydroxybutyrate co 3 hydroxyvalerate and their blend
Polymer, 2007Co-Authors: Korakot Sombatmankhong, Prasit Pavasant, Neeracha Sanchavanakit, Pitt SupapholAbstract:Abstract In the present contribution, electrospinning was used to fabricate ultrafine Fiber mats from poly(3-hydroxybutyrate) (PHB), poly(3-hydroxybutyrate- co -2-hydroxyvalerate) (PHBV), and their 50/50 w/w blend for potential use as bone scaffolds. Cytotoxicity evaluation of these as-Spun Fiber mats with human osteoblasts (SaOS-2) and mouse fibroblasts (L929) indicated biocompatibility of these materials to both types of cells. The potential for use of these Fiber mats as bone scaffolds was further assessed in vitro in terms of the attachment, the proliferation, and the alkaline phosphatase (ALP) activity of SaOS-2 that were seeded or cultured at different times. The cells appeared to adhere well on all types of the fibrous scaffolds after 16 h of cell seeding. During the early stage of the proliferation period (i.e., from ∼24 to 72 h in culture), the viability of the cells increased considerably and appeared to be unchanged with further increase in the time in culture. In comparison with the corresponding solution-cast film scaffolds, all of the fibrous scaffolds exhibited much better support for cell attachment and proliferation. Lastly, among the various fibrous scaffolds investigated, the electroSpun Fiber mat of the 50/50 w/w PHB/PHBV blend showed the highest ALP activity. These results implied a high potential for use of these electroSpun Fiber mats as bone scaffolds.
Sergei Popov - One of the best experts on this subject based on the ideXlab platform.
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two section Fiber optic raman polarizer
IEEE Journal of Quantum Electronics, 2012Co-Authors: Sergey Sergeyev, Sergei PopovAbstract:We report on a theoretical study of polarization impairments in periodically Spun Fiber Raman amplifiers. Based on the Stochastic Generator approach we have derived averaged equations to calculate polarization dependent gain and mean-square gain fluctuations. We show that periodically Spun Fiber can work as a Raman polarizer but it suffers from increased polarization dependent gain and gain fluctuations. Unlike this, application of a depolarizer can result in suppression of polarization dependent gain and gain fluctuations. We demonstrate that it is possible to design a new Fiber Raman polarizer by combining a short Fiber without spin and properly chosen parameters and a long periodically Spun Fiber. This polarizer provides almost the same polarization pulling for all input signal states of polarization and so has very small polarization dependent gain.
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Spun Fiber raman amplifiers with reduced polarization impairments
Optics Express, 2008Co-Authors: Sergey Sergeyev, Sergei Popov, Ari T FribergAbstract:We report a novel vector model of Raman amplification in a Fiber with randomly varying birefringence and unidirectional spin profile. Applying the model, we demonstrate for the first time simultaneous mitigation of polarization mode dispersion and polarization dependence of the Raman gain.
Jianjun Qin - One of the best experts on this subject based on the ideXlab platform.
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effect of wet and dry jet wet spinning on the shear induced orientation during the formation of ultrafiltration hollow Fiber membranes
Journal of Membrane Science, 2001Co-Authors: Jianjun QinAbstract:Abstract We have demonstrated the effect of wet and dry-jet wet spinning on the shear-induced orientation during hollow Fiber membrane formation by characterizing the permeability, separation performance and thermomechanical properties of hollow Fiber ultrafiltration membranes. Both wet-Spun and dry-jet wet Spun Fibers were prepared by using the phase inversion process. An air gap of 1 cm was chosen for the dry-jet wet spinning process in order to minimize gravity effect. To generalize our conclusion, various hollow Fiber UF membranes with different structures were prepared using six spinning dopes with different kinds of polymers, solvents and additives under different shear rates. Experimental results show that pure water flux, coefficient of thermal expansion (CTE) and elongation of the wet Spun Fibers are lower than that of the dry-jet Spun Fibers but separation performance, storage modulus, loss modulus and tensile strength of the wet Spun Fibers are higher. The results indicate that the wet Spun Fiber has smaller pore size and/or a denser skin than the dry-jet wet Spun Fiber. These results also confirm our hypothesis that the molecular orientation induced at the outer skin of the nascent Fiber by shear stress within the spinneret can be frozen into the wet-Spun Fiber but relax in a small air gap region for the dry-jet wet-Spun Fiber. Experimental results strongly indicate that an air gap of 1 cm does make significant impact to the membrane performance . This conclusion arises from the fact that wet Spun Fibers has the greater shear-induced molecular orientation (from spinneret) than the dry-jet wet Spun Fiber and there is strong molecular relaxation in air gap. A hollow Fiber UF membrane with high flux of 1220 L/h m 2 bar can be prepared by the approach proposed in this paper.
Sergey Sergeyev - One of the best experts on this subject based on the ideXlab platform.
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two section Fiber optic raman polarizer
IEEE Journal of Quantum Electronics, 2012Co-Authors: Sergey Sergeyev, Sergei PopovAbstract:We report on a theoretical study of polarization impairments in periodically Spun Fiber Raman amplifiers. Based on the Stochastic Generator approach we have derived averaged equations to calculate polarization dependent gain and mean-square gain fluctuations. We show that periodically Spun Fiber can work as a Raman polarizer but it suffers from increased polarization dependent gain and gain fluctuations. Unlike this, application of a depolarizer can result in suppression of polarization dependent gain and gain fluctuations. We demonstrate that it is possible to design a new Fiber Raman polarizer by combining a short Fiber without spin and properly chosen parameters and a long periodically Spun Fiber. This polarizer provides almost the same polarization pulling for all input signal states of polarization and so has very small polarization dependent gain.
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Spun Fiber raman amplifiers with reduced polarization impairments
Optics Express, 2008Co-Authors: Sergey Sergeyev, Sergei Popov, Ari T FribergAbstract:We report a novel vector model of Raman amplification in a Fiber with randomly varying birefringence and unidirectional spin profile. Applying the model, we demonstrate for the first time simultaneous mitigation of polarization mode dispersion and polarization dependence of the Raman gain.
Ahmad Fauzi Ismail - One of the best experts on this subject based on the ideXlab platform.
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study on the effect of air gap length on properties and performance of surface modified pvdf hollow Fiber membrane contactor for carbon dioxide absorption
Separation and Purification Technology, 2014Co-Authors: Fatemeh Korminouri, Masoud Rahbarisisakht, Dipak Rana, Takeshi Matsuura, Ahmad Fauzi IsmailAbstract:Abstract Surface modified polyvinylidene fluoride (PVDF) hollow Fiber membranes (HFMs) were Spun via dry–wet spinning technique at different air–gap lengths (0–20 cm). The morphology of prepared membranes was evaluated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Membranes were also characterized in terms of gas permeation, overall porosity, collapsing pressure, critical water entry pressure (CEPw) and contact angle. To determine the CO 2 absorption flux of HFMs, a gas–liquid membrane contactor system was used. Experimental results of this study revealed that by increasing the air–gap distance from 0 to 20 cm, wetting resistance and contact angle of fabricated membranes increased due to enhancement of membrane surface hydrophobicity. The highest helium (He) permeation was achieved for the Spun Fiber at the air–gap of 10 cm. From CO 2 absorption experiment it was found that the hollow Fiber Spun at the air–gap of 10 cm had the maximum CO 2 absorption flux of 1.41 × 10 −3 mol/m 2 s at the absorbent flow rate of 300 ml/min, which was significantly higher than CO 2 absorption flux obtained by other researchers. It was also found that both highest He gas permeance and CO 2 absorption flux were controlled by the surface porosity of the hollow Fiber due to the maximum values obtained. Thus, the choice of an appropriate air–gap distance for fabrication of surface modified membranes was found to be a promising method to improve CO 2 removal in membrane contactor systems.