The effect of fiber bleaching treatment on the properties of poly(lactic acid)/oil palm empty fruit bunch fiber composites.

PubMed

Rayung, Marwah; Ibrahim, Nor Azowa; Zainuddin, Norhazlin; Saad, Wan Zuhainis; Razak, Nur Inani Abdul; Chieng, Buong Woei

2014-08-22

In this work, biodegradable composites from poly(lactic acid) (PLA) and oil palm empty fruit bunch (OPEFB) fiber were prepared by melt blending method. Prior to mixing, the fiber was modified through bleaching treatment using hydrogen peroxide. Bleached fiber composite showed an improvement in mechanical properties as compared to untreated fiber composite due to the enhanced fiber/matrix interfacial adhesion. Interestingly, fiber bleaching treatment also improved the physical appearance of the composite. The study was extended by blending the composites with commercially available masterbatch colorant.

The Effect of Fiber Bleaching Treatment on the Properties of Poly(lactic acid)/Oil Palm Empty Fruit Bunch Fiber Composites

PubMed Central

Rayung, Marwah; Ibrahim, Nor Azowa; Zainuddin, Norhazlin; Saad, Wan Zuhainis; Razak, Nur Inani Abdul; Chieng, Buong Woei

2014-01-01

In this work, biodegradable composites from poly(lactic acid) (PLA) and oil palm empty fruit bunch (OPEFB) fiber were prepared by melt blending method. Prior to mixing, the fiber was modified through bleaching treatment using hydrogen peroxide. Bleached fiber composite showed an improvement in mechanical properties as compared to untreated fiber composite due to the enhanced fiber/matrix interfacial adhesion. Interestingly, fiber bleaching treatment also improved the physical appearance of the composite. The study was extended by blending the composites with commercially available masterbatch colorant. PMID:25153628

In vitro evaluation of electrospun PLGA/PLLA/PDLLA blend fibers loaded with naringin for guided bone regeneration.

PubMed

Guo, Zhenzhao; Wu, Shuai; Li, Hong; Li, Qiyan; Wu, Gang; Zhou, Changren

2018-03-30

The present study was to evaluate fiber mesh loaded with naringin via electrospinning to guide bone regeneration in vitro. The naringin-loaded fiber mesh was prepared via elctrospinning of PLGA, PLLA, PDLLA blending solution with naringin. SEM showed that naringin decreased the fiber's diameter according to the concentration of naringin. After 20 days' degradation in PBS, the drug-loaded fiber meshes still kept their stability with about 10% decrease in tensile strength. In vitro release experiments showed a sustained and steady naringin releasing profile with little initial burst releasing. Compared to the mats without naringin, the fiber mats loaded with naringin showed the most pronounced enhancement of cell growth when MC3T3-E1 cells were cultured on the fiber mats. The blend fiber loaded with naringin has optimized physical properties and sustained release profile in vitro. The study presents a promising fibrous mesh material for guided bone regeneration therapy.

Understanding Polymorphism Formation in Electrospun Fibers of Immiscible Poly(vinylidene fluoride) Blends

DOE Office of Scientific and Technical Information (OSTI.GOV)

G Zhong; L Zhang; R Su

2011-12-31

Effects of electric poling, mechanical stretching, and dipolar interaction on the formation of ferroelectric ({beta} and/or {gamma}) phases in poly(vinylidene fluoride) (PVDF) have been studied in electrospun fibers of PVDF/polyacrylonitrile (PAN) and PVDF/polysulfone (PSF) blends with PVDF as the minor component, using wide-angle X-ray diffraction and Fourier transform infrared techniques. Experimental results of as-electrospun neat PVDF fibers (beaded vs. bead-free) showed that mechanical stretching during electrospinning, rather than electric poling, was effective to induce ferroelectric phases. For as-electrospun PVDF blend fibers with the non-polar PSF matrix, mechanical stretching during electrospinning again was capable of inducing some ferroelectric phases in additionmore » to the major paraelectric ({alpha}) phase. However, after removing the mechanical stretching in a confined melt-recrystallization process, only the paraelectric phase was obtained. For as-electrospun PVDF blend fibers with the polar (or ferroelectric) PAN matrix, strong intermolecular interactions between polar PAN and PVDF played an important role in the ferroelectric phase formation in addition to the mechanical stretching effect during electrospinning. Even after the removal of mechanical stretching through the confined melt-recrystallization process, a significant amount of ferroelectric phases persisted. Comparing the ferroelectric phase formation between PVDF/PSF and PVDF/PAN blend fibers, we concluded that the local electric field-dipole interactions were the determining factor for the nucleation and growth of polar PVDF phases.« less

Morphology control in polymer blend fibers—a high throughput computing approach

NASA Astrophysics Data System (ADS)

Sesha Sarath Pokuri, Balaji; Ganapathysubramanian, Baskar

2016-08-01

Fibers made from polymer blends have conventionally enjoyed wide use, particularly in textiles. This wide applicability is primarily aided by the ease of manufacturing such fibers. More recently, the ability to tailor the internal morphology of polymer blend fibers by carefully designing processing conditions has enabled such fibers to be used in technologically relevant applications. Some examples include anisotropic insulating properties for heat and anisotropic wicking of moisture, coaxial morphologies for optical applications as well as fibers with high internal surface area for filtration and catalysis applications. However, identifying the appropriate processing conditions from the large space of possibilities using conventional trial-and-error approaches is a tedious and resource-intensive process. Here, we illustrate a high throughput computational approach to rapidly explore and characterize how processing conditions (specifically blend ratio and evaporation rates) affect the internal morphology of polymer blends during solvent based fabrication. We focus on a PS: PMMA system and identify two distinct classes of morphologies formed due to variations in the processing conditions. We subsequently map the processing conditions to the morphology class, thus constructing a ‘phase diagram’ that enables rapid identification of processing parameters for specific morphology class. We finally demonstrate the potential for time dependent processing conditions to get desired features of the morphology. This opens up the possibility of rational stage-wise design of processing pathways for tailored fiber morphology using high throughput computing.

Preparation and study on the structure of keratin/PVA membrane containing wool fibers

NASA Astrophysics Data System (ADS)

Wu, Min; Shen, Shuming; Yang, Xuhong; Tang, Rencheng

2017-10-01

The urea / sodium sulfide / sodium dodecyl sulfate (SDS) method was used to dissolve the wool in this study. Then the Wool fiber/keratin/PVA composites with different proportions were prepared, and the surface morphology, molecular structure, mechanical property of the composite films and the influence of the proportions on their structure and properties were studied. The results showed that, there are α-helix structure, β-sheet and random coil conformations in the pure keratin film, as well as in the wool fiber. Compared with wool fiber, the crystallinity of keratin decreased. PVA can obviously improve the mechanical property of the blended film. When the blended ratio of keratin/PVA is 20/80, the mechanical property of the blended film is greatly improved. The composite films with 8%-16% of wool fibers have better flexibility than those without wool fibers.

Morphology and properties of wood-fiber reinforced blends of recycled polystyrene and polyethylene

Treesearch

John Simonsen; Timothy G. Rials

1996-01-01

Material properties of composites produced from recycled plastics and recycled wood fiber were compared. A blend of high-density polyethylene and polystyrene was used as a simulated mixed plastic. Stiffness was generally improved by the addition of fiber, as expected, but brittleness also increased. Pre-treatment of the wood filler with phenol-formaldehyde resins did...

A novel use of bio-based natural fibers, polymers, and rubbers for composite materials

NASA Astrophysics Data System (ADS)

Modi, Sunny Jitendra

The composites, materials, and packaging industries are searching for alternative materials to attain environmental sustainability. Bio-plastics are highly desired and current microbially-derived bio-plastics, such as PHA (poly-(hydroxy alkanoate)), PHB (poly-(hydroxybutyrate)), and PHBV (poly-(beta-hydroxy butyrate-co-valerate)) could be engineered to have similar properties to conventional thermoplastics. Poly-(hydroxybutyrate) (PHB) is a bio-degradable aliphatic polyester that is produced by a wide range of microorganisms. Basic PHB has relatively high glass transition and melting temperatures. To improve flexibility for potential packaging applications, PHB is synthesized with various co-polymers such as Poly-(3-hydroxyvalerate) (HV) to decrease the glass and melting temperatures and, since there is improved melt stability at lower processing temperatures, broaden the processing window. However, previous work has shown that this polymer is too brittle, temperature-sensitive, and hydrophilic to meet packaging material physical requirements. Therefore, the proposed work focuses on addressing the needs for bio-derived and bio-degradable materials by creating a range of composite materials using natural fibers as reinforcement agents in bio-polymers and bio- plastic-rubber matrices. The new materials should possess properties lacking in PHBV and broaden the processing capabilities, elasticity, and improve the mechanical properties. The first approach was to create novel composites using poly-(beta-hydroxy butyrate-co-valerate) (PHBV) combined with fibers from invasive plants such as common reed (Phragmites australis), reed canary grass (Phalaris arundinacea), and water celery ( Vallisneria americana). The composites were manufactured using traditional processing techniques of extrusion compounding followed by injection molding of ASTM type I parts. The effects of each bio-fiber at 2, 5, and 10% loading on the mechanical, morphological, rheological, and thermal properties of PHBV were investigated. Many of the composites showed miscible blends between the fibers and PHBV. The SEM analysis showed finely dispersed water celery bio-fibers into the PHBV matrix indicating compatibility between this fiber and the PHBV matrix. The finely ground water celery fibers increased the fiber-matrix interactions without the use of additives or compatibilizers. When the mechanical properties of the composites were compared to pure PHBV, the composites showed improvements in the tensile modulus, while limited changes were observed in the tensile strength and elongation at break. Also, improvements in the viscosity at 170¨¬C over pure PHBV were observed with the addition of 10% by weight bio-fibers due to fiber-fiber and fiber-matrix interactions. With these improvements in the melt stability, the composites can be processed above the melting temperature of 165-170°C, a marked benefit over pure PHBV. The brittle nature of PHBV and its relatively high water transmission rates making it unsuitable for packaging applications. New blends of PHBV with high molecular weight natural rubber of matched viscosity were developed. The mechanical, rheological, and thermal properties of the blends with 5, 10, 15, and 25% by weight high molecular weight natural rubber (HMW-NR) were characterized; in addition, the water vapor transmission rates of these blends was determined. The results showed increased thermal stability and more uniform melting peaks for the blends compared to pure PHBV. The water permeation decreased with the addition of HMW-NR, and the permeation rates were similar to that of traditional thermoplastics. The addition of rubber increased the elongation at break without adversely affecting the Young's modulus for the blends. The complex viscosity of the blends was improved by one log over pure PHBV at 170ºC suggesting improved thermal stability of the blends. During creep and recovery testing, higher compliance values of the blends suggest increased entanglements network of PHBV and rubber micro-fibrils preventing the blends from developing permanent deformation. Therefore, these blends can potentially be used in-place of transitional thermoplastics in casting sheets and thermoforming.

Interfacial adhesion of carbon fibers

NASA Technical Reports Server (NTRS)

Bascom, Willard D.

1987-01-01

Relative adhesion strengths between AS4, AS1, and XAS carbon fibers and thermoplastic polymers were determined using the embedded single filament test. Polymers studied included polycarbonate, polyphenylene oxide, polyetherimide, polysulfone, polyphenylene oxide blends with polystyrene, and polycarbonate blends with a polycarbonate polysiloxane block copolymer. Fiber surface treatments and sizings improved adhesion somewhat, but adhesion remained well below levels obtained with epoxy matrices. An explanation for the differences between the Hercules and Grafil fibers was sought using X ray photon spectroscopy, wetting, scanning electron microscopy and thermal desorption analysis.

Military Uniforms: Issues Related to the Supply of Flame Resistant Fibers for the Production of Military Uniforms

DTIC Science & Technology

2011-06-30

fibers. A variety of fibers may be used to create a fabric blend, including FR rayon, Nomex®, Twaron®, Kevlar®, FR cotton, polybenzimidazole ( PBI ...as meta-aramids (e.g., Nomex®), modacrylic, PBI , and FR-treated cotton. o For example, the Army is currently testing fabrics in an attempt to...considering fabric blends containing FR-treated cotton as a potential alternative. o The Marine Corps uses PBI fibers in its balaclava (a protective

Miscible blends of biobased poly(lactide) with poly(methyl methacrylate): Effects of chopped glass fiber incorporation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cousins, Dylan S.; Lowe, Corinne; Swan, Dana

Poly(lactide) (PLA) and poly(methyl methacrylate) (PMMA) are melt compounded with chopped glass fiber using laboratory scale twin-screw extrusion. Physical properties are examined using differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), thermogravimetric analysis (TGA), tensile testing, impact testing, X-ray computed tomography (CT) scanning, and field emission scanning electron microscopy (FE-SEM). Molecular weight is determined using gel permeation chromatography (GPC). Miscibility of the blends is implied by the presence of a single glass transition temperature and homogeneous morphology. PLA/PMMA blends tend to show positive deviations from a simple linear mixing rule in their mechanical properties (e.g., tensile toughness, modulus, andmore » stress at break). The addition of 40 wt % glass fiber to the system dramatically increases physical properties. Across all blend compositions, the tensile modulus increases from roughly 3 GPa to roughly 10 GPa. Estimated heat distortion temperatures (HDTs) are also greatly enhanced; the pure PLA sample HDT increases from 75 degrees C to 135 degrees C. Fiber filled polymer blends represent a sustainable class of earth abundant materials which should prove useful across a range of applications.« less

Enrichment of rice-based extrudates with Cactus Opuntia dillenii seed powder: a novel source of fiber and antioxidants.

PubMed

Rayan, Ahmed M; Morsy, Noha E; Youssef, Khaled M

2018-02-01

The present study investigated the effects of adding the powder of cactus Opuntia dillenii ( O. dillenii ) seeds on the functional properties, fiber, antioxidants and acceptability of rice-based extrudates. The control blend consisting basically of rice flour was replaced with O. dillenii seed powder at 2, 4, 6, 8, 10, 15 and 20% then extruded at the optimum processing conditions. The extruded products were evaluated for their chemical composition, functional properties, color attributes, antioxidant activity and sensory characteristics. The results revealed that adding O. dillenii seeds powder enhanced the fiber, phenolics, flavonoid contents and antioxidant activity of extrudates. Expansion, bulk density and breaking strength were significantly decreased, while water absorption index, water solubility index and oil absorption index were significantly increased compared to the control. Furthermore, the mean scores of sensory evaluation indicated clear improvements in all tested sensory attributes, which significantly increased by increasing the level of O. dillenii seed powder up to 15%. The results confirmed that O. dillenii seed powder could be incorporated in rice to develop snack products of acceptable functional, nutritional and sensory properties.

Multifilament cellulose/chitin blend yarn spun from ionic liquids.

PubMed

Mundsinger, Kai; Müller, Alexander; Beyer, Ronald; Hermanutz, Frank; Buchmeiser, Michael R

2015-10-20

Cellulose and chitin, both biopolymers, decompose before reaching their melting points. Therefore, processing these unmodified biopolymers into multifilament yarns is limited to solution chemistry. Especially the processing of chitin into fibers is rather limited to distinctive, often toxic or badly removable solvents often accompanied by chemical de-functionalization to chitosan (degree of acetylation, DA, <50%). This work proposes a novel method for the preparation of cellulose/chitin blend fibers using ionic liquids (ILs) as gentle, removable, recyclable and non-deacetylating solvents. Chitin and cellulose are dissolved in ethylmethylimidazolium propionate ([C2mim](+)[OPr](-)) and the obtained one-pot spinning dope is used to produce multifilament fibers by a continuous wet-spinning process. Both the rheology of the corresponding spinning dopes and the structural and physical properties of the obtained fibers have been determined for different biopolymer ratios. With respect to medical or hygienic application, the cellulose/chitin blend fiber show enhanced water retention capacity compared to pure cellulose fibers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Manufacturing and characterization of encapsulated microfibers with different molecular weight poly(ε-caprolactone) (PCL) resins using a melt electrospinning technique

NASA Astrophysics Data System (ADS)

Lee, Jason K.; Ko, Junghyuk; Jun, Martin B. G.; Lee, Patrick C.

2016-02-01

Encapsulated structures of poly(ε-caprolactone) microfibers were successfully fabricated through two distinct melt electrospinning methods: melt coaxial and melt-blending electrospinning methods. Both methods resulted in encapsulated microfibers, but the resultant microfibers had different morphologies. Melt coaxial electrospinning formed a dual, semi-concentric structure, whereas melt-blending electrospinning resulted in an islands-in-a-sea fiber structure (i.e. a multiple-core structure). The encapsulated microfibers were produced using a custom-designed melt coaxial electrospinning device and the microfibers were characterized using a scanning electron microscope. To analyze the properties of the melt blended encapsulated fibers and coaxial fibers, the microfiber mesh specimens were collected. The mechanical properties of each microfiber mesh were analyzed through a tensile test. The coaxial microfiber meshes were post processed with a femtosecond laser machine to create dog-bone shaped tensile test specimens, while the melt blended microfiber meshes were kept as-fabricated. The tensile experiments undertaken with coaxial microfiber specimens resulted in an increase in tensile strength compared to 10 k and 45 k monolayer specimens. However, melt blended microfiber meshes did not result in an increase in tensile strength. The melt blended microfiber mesh results indicate that by using greater amounts of 45 k PCL resin within the microstructure, the resulting fibers obtain a higher tensile strength.

Electrospinning of guar gum/corn starch blends

USDA-ARS?s Scientific Manuscript database

In this study, electrospun nanofibers were prepared for the first time from aqueous blends of guar gum (GG) and corn starch with amylose contents of 27.8% (CS28) and 50% (CS50). The fiber morphology and fiber diameter sizes (FDS) were correlated with solution rheology. The spinning solutions were pr...

The use of synthetic blended fibers to reduce cracking risk in high performance concrete.

DOT National Transportation Integrated Search

2014-09-01

The aim of this project was to investigate a relatively new technique to control early-age cracking; the : use of blended size polypropylene fibers in high performance concrete mixtures. The key findings : from this work were that the use of drying s...

Comprehensive characterization of chitosan/PEO/levan ternary blend films.

PubMed

Bostan, Muge Sennaroglu; Mutlu, Esra Cansever; Kazak, Hande; Sinan Keskin, S; Oner, Ebru Toksoy; Eroglu, Mehmet S

2014-02-15

Ternary blend films of chitosan, PEO (300,000) and levan were prepared by solution casting method and their phase behavior, miscibility, thermal and mechanical properties as well as their surface energy and morphology were characterized by different techniques. FT-IR analyses of blend films indicated intermolecular hydrogen bonding between blend components. Thermal and XRD analysis showed that chitosan and levan suppressed the crystallinity of PEO up to nearly 25% of PEO content in the blend, which resulted in more amorphous film structures at higher PEO/(chitosan+levan) ratios. At more than 30% of PEO concentration, contact angle (CA) measurements showed a surface enrichment of PEO whereas at lower PEO concentrations, chitosan and levan were enriched on the surfaces leading to more amorphous and homogenous surfaces. This result was further confirmed by atomic force microscopy (AFM) images. Cell proliferation and viability assay established the high biocompatibility of the blend films. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fabrication of drug-loaded electrospun aligned fibrous threads for suture applications.

PubMed

He, Chuang-Long; Huang, Zheng-Ming; Han, Xiao-Jian

2009-04-01

In this work, drug-loaded fibers and threads were successfully fabricated by combining electrospinning with aligned fibers collection. Two different electrospinning processes, that is, blend and coaxial electrospinning, to incorporate a model drug tetracycline hydrochloride (TCH) into poly(L-lactic acid) (PLLA) fibers have been used and compared with each other. The resulting composite ultrafine fibers and threads were characterized through scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, and tensile testing. It has been shown that average diameters of the fibers made from the same polymer concentration depended on the processing method. The blend TCH/PLLA fibers showed the smallest fiber diameter, whereas neat PLLA fibers and core-shell TCH-PLLA fibers showed a larger proximal average diameter. Higher rotating speed of a wheel collector is helpful for obtaining better-aligned fibers. Both the polymer and the drug in the electrospun fibers have poor crystalline property. In vitro release study indicated that threads made from the core-shell fibers could suppress the initial burst release and provide a sustained drug release useful for the release of growth factor or other therapeutic drugs. On the other hand, the threads from the blend fibers produced a large initial burst release that may be used to prevent bacteria infection. A combination of these results suggests that electrospinning technique provides a novel way to fabricate medical agents-loaded fibrous threads for tissue suturing and tissue regeneration applications. Copyright 2008 Wiley Periodicals, Inc.

Morphological and mechanical characterization of thermoplastic starch and its blends with polylactic acid using cassava starch and bagasse

USDA-ARS?s Scientific Manuscript database

This study aims the use of an agro waste coming from the industrialization of cassava starch, known as cassava bagasse (BG). This material contains residual starch and cellulose fibers which can be used to obtain thermoplastic starch (TPS) and /or blends reinforced with fibers. In this context, it w...

Dietary Fiber-Induced Changes in the Structure and Thermal Properties of Gluten Proteins Studied by Fourier Transform-Raman Spectroscopy and Thermogravimetry.

PubMed

Nawrocka, Agnieszka; Szymańska-Chargot, Monika; Miś, Antoni; Wilczewska, Agnieszka Z; Markiewicz, Karolina H

2016-03-16

Interactions between gluten proteins and dietary fiber supplements at the stage of bread dough formation are crucial in the baking industry. The dietary fiber additives are regarded as a source of polysaccharides and antioxidants, which have positive effects on human health. The fiber enrichment of bread causes a significant reduction in its quality, which is connected with changes in the structure of gluten proteins. Changes in the structure of gluten proteins and their thermal properties induced by seven commercial dietary fibers (fruit, vegetable, and cereal) were studied by FT-Raman spectroscopy and thermogravimetry (TGA), respectively. For this aim the bread dough at 500 FU consistency was made of a blend of wheat starch and wheat gluten as well as the fiber, the content of which ranged from 3 to 18% w/w. The obtained results revealed that all dietary fibers apart from oat caused similar changes in the secondary structure of gluten proteins. The most noticeable changes were observed in the regions connected with hydrogen-bonded β-sheets (1614 and 1684 cm(-1)) and β-turns (1640 and 1657 cm(-1)). Other changes observed in the gluten structure, concerning other β-structures, conformation of disulfide bridges, and aromatic amino acid microenvironment, depend on the fibers' chemical composition. The results concerning structural changes suggested that the observed formation of hydrogen bonds in the β-structures can be connected with aggregation or abnormal folding. This hypothesis was confirmed by thermogravimetric results. Changes in weight loss indicated the formation of a more complex and strong gluten network.

Electrospun Polymer Blend Nanofibers for Tunable Drug Delivery: The Role of Transformative Phase Separation on Controlling the Release Rate.

PubMed

Tipduangta, Pratchaya; Belton, Peter; Fábián, László; Wang, Li Ying; Tang, Huiru; Eddleston, Mark; Qi, Sheng

2016-01-04

Electrospun fibrous materials have a wide range of biomedical applications, many of them involving the use of polymers as matrices for incorporation of therapeutic agents. The use of polymer blends improves the tuneability of the physicochemical and mechanical properties of the drug loaded fibers. This also benefits the development of controlled drug release formulations, for which the release rate can be modified by altering the ratio of the polymers in the blend. However, to realize these benefits, a clear understanding of the phase behavior of the processed polymer blend is essential. This study reports an in depth investigation of the impact of the electrospinning process on the phase separation of a model partially miscible polymer blend, PVP K90 and HPMCAS, in comparison to other conventional solvent evaporation based processes including film casting and spin coating. The nanoscale stretching and ultrafast solvent removal of electrospinning lead to an enhanced apparent miscibility between the polymers, with the same blends showing micronscale phase separation when processed using film casting and spin coating. Nanoscale phase separation in electrospun blend fibers was confirmed in the dry state. Rapid, layered, macroscale phase separation of the two polymers occurred during the wetting of the fibers. This led to a biphasic drug release profile from the fibers, with a burst release from PVP-rich phases and a slower, more continuous release from HPMCAS-rich phases. It was noted that the model drug, paracetamol, had more favorable partitioning into the PVP-rich phase, which is likely to be a result of greater hydrogen bonding between PVP and paracetamol. This led to higher drug contents in the PVP-rich phases than the HPMCAS-rich phases. By alternating the proportions of the PVP and HPMCAS, the drug release rate can be modulated.

Experimental investigation on flexure and impact properties of injection molded polypropylene-nylon 6-glass fiber polymer composites

NASA Astrophysics Data System (ADS)

Nuruzzaman, D. M.; Kusaseh, N. M.; Chowdhury, M. A.; Rahman, N. A. N. A.; Oumer, A. N.; Fatchurrohman, N.; Iqbal, A. K. M. A.; Ismail, N. M.

2018-04-01

In this research study, glass fiber (GF) reinforced polypropylene (PP)-nylon 6 (PA6) polymer blend composites were prepared using injection molding process. Specimens of four different compositions such as 80%PP+20%PA6, 80%PP+18%PA6+2%GF, 80%PP+16%PA6+4%GF and 80%PP+14%PA6+6%GF were prepared. In the injection molding process, suitable process parameters were selected depending on the type of composite specimen in producing defects free dog bone shaped specimens. Flexure and impact tests were carried out according to ASTM standard. The important flexure properties such as flexural modulus, flexural yield strength, flexural strength and flexural strain were investigated. The obtained results revealed that flexural modulus of 80%PP+20%PA6 polymer blend is the lowest and the polymer blend composite shows steadily improved modulus as the glass fiber content is increased. Results also showed that flexural strength of pure polymer blend is the lowest but it improves gradually when the glass fiber content is increased. Impact test results revealed that impact strength of 80%PP+20%PA6 polymer blend is the highest whereas all the composites show reduced impact strength or toughness. It is noticed that 80%PP+14%PA6+6%GF composite exhibits the lowest impact strength.

A new class of boron nitride fibers with tunable properties by combining an electrospinning process and the polymer-derived ceramics route

NASA Astrophysics Data System (ADS)

Salles, Vincent; Bernard, Samuel; Brioude, Arnaud; Cornu, David; Miele, Philippe

2010-02-01

Novel boron nitride (BN) fibers have been developed with diameters ranging from the nano- to microscale by thermal conversion of as-electrospun fibers from polyacrylonitrile and poly[B-(methylamino)borazine] blend solutions. Such a new class of ceramic fibers is seen as potential candidate for thermal management applications and filtration systems in harsh environments.Novel boron nitride (BN) fibers have been developed with diameters ranging from the nano- to microscale by thermal conversion of as-electrospun fibers from polyacrylonitrile and poly[B-(methylamino)borazine] blend solutions. Such a new class of ceramic fibers is seen as potential candidate for thermal management applications and filtration systems in harsh environments. Electronic supplementary information (ESI) available: Experimental details and EDX results. See DOI: 10.1039/b9nr00185a

Development of electrospun beaded fibers from Thai silk fibroin and gelatin for controlled release application.

PubMed

Somvipart, Siraporn; Kanokpanont, Sorada; Rangkupan, Rattapol; Ratanavaraporn, Juthamas; Damrongsakkul, Siriporn

2013-04-01

Thai silk fibroin and gelatin are attractive biomaterials for tissue engineering and controlled release applications due to their biocompatibility, biodegradability, and bioactive properties. The development of electrospun fiber mats from silk fibroin and gelatin were reported previously. However, burst drug release from such fiber mats remained the problem. In this study, the formation of beads on the fibers aiming to be used for the sustained release of drug was of our interest. The beaded fiber mats were fabricated using electrospinning technique by controlling the solution concentration, weight blending ratio of Thai silk fibroin/gelatin blend, and applied voltage. It was found that the optimal conditions including the solution concentration and the weight blending ratio of Thai silk fibroin/gelatin at 8-10% (w/v) and 70/30, respectively, with the applied voltage at 18 kV provided the fibers with homogeneous formation of beads. Then, the beaded fiber mats obtained were crosslinked by the reaction of carbodiimide hydrochloride (EDC)/N-hydroxysuccinimide (NHS). Methylene blue as a model active compound was loaded on the fiber mats. The release test of methylene blue from the beaded fiber mats was carried out in comparison to that of the smooth fiber mats without beads. It was found that the beaded fiber mats could prolong the release of methylene blue, comparing to the smooth fiber mats without beads. This was possibly due to the beaded fiber mats that would absorb and retain higher amount of methylene blue than the fiber mats without beads. Thai silk fibroin/gelatin beaded fiber mats were established as an effective carrier for the controlled release applications. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of liquid epoxidized natural rubber (LENR) on mechanical properties and morphology of natural rubber/high density polyethylene/mengkuang fiber (NR/HDPE/MK) bio-composite

NASA Astrophysics Data System (ADS)

Piah, Mohd Razi Mat; Baharum, Azizah

2016-11-01

The use of mengkuang fiber (MK) fibers in NR/HDPE (40/60) blend was studied via surface modification of fiber. The MK fiber was pre-washed with 5%wt/v sodium hydroxide solution prior to treatment with liquid epoxidized natural rubber (LENR). The concentration of LENR were varied from 5%-20%wt in toluene. The effects of LENR concentrations were studied in terms of mechanical properties and morphology formed. Melt-blending was performed using an internal mixer (Haake Rheomix 600). The processing parameters identified were 135°C temperature, 45 rpm rotor speed, 12 minutes processing time and at 20%wt MK fiber loading. The optimum LENR treatment concentration was obtained at 5%wt with tensile strength, tensile modulus, and impact strength of 10.3 MPa, 414.2 MPa and 14.4 kJ/m2 respectively. The tensile modulus of LENR-treated MK fiber filled NR/HDPE bio-composite has shown enhancement up to 16.7% higher than untreated MK fiber. The tensile and impact strength were decreased with increasing LENR concentration due to the broken of MK fibers to smaller particles and adhered to each other. FESEM micrographs confirmed the formation of fiber-fiber agglomeration in NR/HDPE blends. The optical microscope analysis shows MK fibers is shorter than original fiber lengths after NaOH-LENR surface modification. The internal bonding forces of MK fiber seems to be weaker than external force exerted on it, therefore, the MK fiber has broken to smaller particles and reduced the mechanical properties of NR/HDPE/MK(20%) bio-composite.

Fiber webs

Treesearch

Roger M. Rowell; James S. Han; Von L. Byrd

2005-01-01

Wood fibers can be used to produce a wide variety of low-density three-dimensional webs, mats, and fiber-molded products. Short wood fibers blended with long fibers can be formed into flexible fiber mats, which can be made by physical entanglement, nonwoven needling, or thermoplastic fiber melt matrix technologies. The most common types of flexible mats are carded, air...

Evaluation of rheological, bioactives and baking characteristics of mango ginger (curcuma amada) enriched soup sticks.

PubMed

Crassina, K; Sudha, M L

2015-09-01

Wheat flour was replaced with mango ginger powder (MGP) at 0, 5, 10 and 15 %. Influence of MGP on rheological and baking characteristics was studied. Farinograph was used to study the mixing profile of wheat flour-MGP blend. Pasting profile of the blends namely gelatinization and retrogradation were carried out using micro-visco-amylograph. Test baking was done to obtain the optimum level of replacement and processing conditions. Sensory attributes consisting texture, taste, overall quality and breaking strength were assessed. Nutritional characterization of the soup sticks in terms of protein and starch in vitro digestibility, dietary fiber, minerals, polyphenols and antioxidant activity were determined using standard methods. With the increasing levels of MGP from 0 to 15 %, the farinograph water absorption increased from 60 to 66.7 %. A marginal increase in the gelatinization temperature from 65.4 to 66.2 °C was observed. Retrogradation of gelatinized starch granules decreased with the addition of MGP. The results indicated that the soup stick with 10 % MG had acceptable sensory attributes. The soup stick showed further improvement in terms of texture and breaking strength with the addition of gluten powder, potassium bromate and glycerol monostearate. The total dietary fiber and antioxidant activity of the soup sticks having 10 % MGP increased from 3.31 to 8.64 % and 26.83 to 48.06 % respectively as compared to the control soup sticks. MGP in soup sticks improved the nutritional profile.

Gasohol Quality Control for Real Time Applications by Means of a Multimode Interference Fiber Sensor

PubMed Central

Rodríguez Rodríguez, Adolfo J.; Baldovino-Pantaleón, Oscar; Domínguez Cruz, Rene F.; Zamarreño, Carlos R.; Matías, Ignacio R.; May-Arrioja, Daniel A.

2014-01-01

In this work we demonstrate efficient quality control of a variety of gasoline and ethanol (gasohol) blends using a multimode interference (MMI) fiber sensor. The operational principle relies on the fact that the addition of ethanol to the gasohol blend reduces the refractive index (RI) of the gasoline. Since MMI sensors are capable of detecting small RI changes, the ethanol content of the gasohol blend is easily determined by tracking the MMI peak wavelength response. Gasohol blends with ethanol contents ranging from 0% to 50% has been clearly identified using this device, which provides a linear response with a maximum sensitivity of 0.270 nm/% EtOH. The sensor can also distinguish when water incorporated in the blend has exceeded the maximum volume tolerated by the gasohol blend, which is responsible for phase separation of the ethanol and gasoline and could cause serious engine failures. Since the MMI sensor is straightforward to fabricate and does not require any special coating it is a cost effective solution for real time and in-situ monitoring of the quality of gasohol blends. PMID:25256111

Surface and interfacial properties of carbon fibers

NASA Technical Reports Server (NTRS)

Bascom, Willard D.

1991-01-01

The adhesion strength of AS4 fibers to thermoplastic polymers was determined. The specific polymers were polycarbonate, polyphenylene oxide, polyetherimide, polyphenylene oxide blends with polystyrene, and polycarbonate blends with a polycarbonate-polysiloxan copolymer. Data are also included for polysulfone. It was recognized at the outset that an absolute measure of the fiber matrix adhesion would be difficult. However, it is feasible to determine the fiber bond strengths to the thermoplastics relative to the bond strengths of the same fibers to epoxy polymers. It was anticipated, and in fact realized, that the adhesion of AS4 to the thermoplastic polymers was relatively low. Therefore, further objectives of the study were to identify means of increasing fiber/matrix adhesion and to try to determine why the adhesion of AS4 to thermoplastics is significantly less than to epoxy polymers.

Blending of soluble corn fiber with pullulan, sorbitol, or fructose attenuates glycemic and insulinemic responses in the dog and affects hydrolytic digestion in vitro.

PubMed

de Godoy, M R C; Knapp, B K; Bauer, L L; Swanson, K S; Fahey, G C

2013-08-01

The objective of these experiments was to measure in vitro hydrolytic digestion and glycemic and insulinemic responses of select carbohydrate blends, all containing the novel carbohydrate soluble corn fiber (SCF). Two SCF that varied in their method of production were used to formulate the carbohydrate blends. One set of blends contained a SCF that was spray dried (SCFsd) and then blended with different amounts of either pullulan, sorbitol, or fructose. The other set of blends contained a SCF produced using longer evaporation time (SCF) and then blended with different ratios of pullulan, sorbitol, and fructose. Free sugar concentrations found in the individual SCFsd and SCF substrates were low but varied. Spray-dried soluble corn fiber had a reduced free sugar concentration compared with SCF (2.8 vs. 14.2%). Glucose was the main free sugar found in both SCFsd and SCF but at different concentrations (2.7 vs. 12.7%, respectively). The majority of the SCFsd blends were completely hydrolyzed to their monosaccharide components. Glucose accounted for most of the hydrolyzed monosaccharides for SCFsd and all the SCFsd blends. Hydrolyzed monosaccharide concentrations for the SCF:pullulan:sorbitol:fructose blends followed similar trends to the SCFsd blends where greater percentages of fructose and sorbitol resulted in decreased (P < 0.05) hydrolyzed monosaccharide concentrations. The SCFsd blends had intermediate to high amounts of monosaccharides released as a result of in vitro hydrolytic digestion. The SCFsd:pullulan blends were more digestible in vitro (approximately 91%; P < 0.05) than SCFsd:fructose or SCFsd:sorbitol. Total released monosaccharides were high in SCFsd blends containing either 50% fructose or sorbitol, but the combination resulted in reduced concentrations of glucose released (P < 0.05). The SCF:pullulan:sorbitol:fructose blends also had intermediate to high released monosaccharides as a result of in vitro hydrolytic digestion. All SCF blends resulted in decreased glycemic and insulinemic responses compared with the maltodextrin control (P < 0.05) using a canine model. The addition of pullulan reduced the glycemic response compared with maltodextrin at all concentrations, but only 50:50 SCFsd:pullulan resulted in a reduction of the glycemic response compared with SCFsd alone (P < 0.05). The addition of fructose and sorbitol in the blends had the greatest impact on glycemic and insulinemic responses, even at concentrations as low as 5% of the blends. Overall, SCF and their blends may prove beneficial as components of low glycemic foodstuffs.

Benefits of dietary fiber in clinical nutrition.

PubMed

Klosterbuer, Abby; Roughead, Zamzam Fariba; Slavin, Joanne

2011-10-01

Dietary fiber is widely recognized as an important part of a healthy diet and is a common addition to enteral nutrition (EN) formulas. Fiber sources differ in characteristics such as solubility, fermentability, and viscosity, and it is now well known that different types of fiber exert varying physiological effects in the body. Clinical studies suggest fiber can exert a wide range of benefits in areas such as bowel function, gut health, immunity, blood glucose control, and serum lipid levels. Although early clinical nutrition products contained fiber from a single source, it is now thought that blends of fiber from multiple sources more closely resemble a regular diet and may provide a greater range of benefits for the patient. Current recommendations support the use of dietary fiber in clinical nutrition when no contraindications exist, but little information exists about which types and combinations of fibers provide the relevant benefit in certain patient populations. This article summarizes the different types of fiber commonly added to EN products and reviews the current literature on the use of fiber blends in clinical nutrition.

The impact of extrusion on the nutritional composition, dietary fiber and in vitro digestibility of gluten-free snacks based on rice, pea and carob flour blends.

PubMed

Arribas, C; Cabellos, B; Sánchez, C; Cuadrado, C; Guillamón, E; Pedrosa, M M

2017-10-18

Consumers and the food industry are demanding healthier products. Expanded snacks with a high nutritional value were developed from different rice, pea and carob flour blends. The proximate composition, starch (total and resistant), amylose and amylopectin, dietary fiber (soluble and insoluble) contents, and the in vitro protein digestibility of different rice-legume formulations, were evaluated before and after the extrusion process. Compared with the corresponding non-extruded blends (control), the extrusion treatment did not change the total protein content, however, it reduced the soluble protein (61-86%), the fat (69-92%) and the resistant starch contents (100%). The total starch content of all studied blends increased (2-19%) after extrusion. The processing increased the in vitro protein digestibility, reaching values around 88-95% after extrusion. Total dietary fiber was reduced around 30%, and the insoluble fraction was affected to a larger extent than the soluble fraction by the extrusion process. Because of its balanced nutritional composition, high dietary fiber content, as well as low energy density, these novel gluten-free snack-like foods could be considered as functional foods and a healthier alternative to commercially available gluten-containing or gluten-free and low nutritional value snacks.

Recycled fiber quality from a laboratory-scale blade separator/blend

Treesearch

Bei-Hong Liang; Stephen M. Shaler; Laurence Mott; Leslie Groom

1994-01-01

A simple and inexpensive fiber separator/blender was developed to generate useful secondary fibers from hydropulped waste paper. Processing wet hydropulped fiber resulted in a furnish with no change in average fiber length in three out of four types of recycled fibers tested. In all cases, the Canadian Standard freeness increased after processing compared to...

Effect of incorporation of corn byproducts on quality of baked and extruded products from wheat flour and semolina.

PubMed

Sharma, Savita; Gupta, Jatinder Pal; Nagi, H P S; Kumar, Rakesh

2012-10-01

The effect of blending level (0, 5, 10, 15 and 20%) of corn bran, defatted germ and gluten with wheat flour on the physico-chemical properties (protein, crude fiber, phosphorus, iron and calcium), baking properties of bread, muffins and cookies, and extrusion properties of noodles and extruded snacks prepared from semolina were examined. Blending of wheat flour and corn byproducts significantly increased the protein, crude fiber, phosphorus, iron and calcium contents. Breads from gluten blends had higher loaf volume as compared to bran and germ breads. Among corn byproducts, gluten cookies were rated superior with respect to top grain. Muffins from germ blends and gluten blends had higher acceptability scores than the bran muffins. Blending of corn bran, defatted germ and gluten at 5 and 10% with wheat flour resulted in satisfactory bread, cookie, and muffin score. Quality of noodles was significantly influenced by addition of corn byproducts and their levels. Corn byproducts blending had significant influence on cooking time, however, gruel solid loss affected non-significantly in case of noodles. Expansion ratio and density of extruded snacks was affected non significantly by blending source and blending level. However, significant effect was observed on amperage, pressure, yield and overall acceptability of extruded snacks. Acceptable extruded products (noodles and extruded snacks) could be produced by blending corn byproducts with semolina upto 10% level.

Properties of foam and composite materials made o starch and cellulose fiber

USDA-ARS?s Scientific Manuscript database

Composite materials were made of starch and cellulose fibers. Pre-gelatinized starch was effective in dispersing pulp fiber in a starch matrix to form a viscous starch/fiber dough. The starch/fiber dough was a useful feedstock for various composite foam and plastic materials. Viscous blends of star...

In vitro starch digestion and cake quality: impact of the ratio of soluble and insoluble dietary fiber.

PubMed

Oh, Im Kyung; Bae, In Young; Lee, Hyeon Gyu

2014-02-01

The influence of the ratio of soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) on the in vitro starch digestion, predicted glycemic index (pGI), and the physicochemical properties of fiber-enriched cakes were evaluated. The hydration and pasting properties were affected by the ratio of SDF and IDF. According to the increase of IDF ratio (SDF ratio reduction) in 3 g fiber-enriched cakes, slowly digestible starch (SDS) contents increased, while the rapidly digestible starch (RDS) contents decreased. The pGI values were significantly different with control in 3 g fiber-enriched cake containing more than 50% IDF contents (p<0.05). But the pGI values of 6g fiber-enriched cake samples were not significantly different by SDF and IDF ratio. With the exception of the SDF 100% cake, volume index, hardness, and color values of the fiber-enriched cakes increased according to reductions in the SDF ratio. The cakes containing 3 g of total dietary fiber (the same ratio of SDF and IDF) per serving were shown to have low pGI and acceptable quality attributes. Specially, total dietary fiber amount and IDF ratio are more effective than SDF ratio to lower the pGI value. Copyright © 2013 Elsevier B.V. All rights reserved.

Biodegradable-Polymer-Blend-Based Surgical Sealant with Body-Temperature-Mediated Adhesion.

PubMed

Behrens, Adam M; Lee, Nora G; Casey, Brendan J; Srinivasan, Priya; Sikorski, Michael J; Daristotle, John L; Sandler, Anthony D; Kofinas, Peter

2015-12-22

The development of practical and efficient surgical sealants has the propensity to improve operational outcomes. A biodegradable polymer blend is fabricated as a nonwoven fiber mat in situ. After direct deposition onto the tissue of interest, the material transitions from a fiber mat to a film. This transition promotes polymer-substrate interfacial interactions leading to improved adhesion and surgical sealant performance. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fabrication of Tunable Submicro- or Nano-structured Polyethylene Materials form Immiscible Blends with Cellulose Acetate Butyrate

USDA-ARS?s Scientific Manuscript database

Low density polyethylene (LDPE) was prepared into micro- or submicro-spheres or nanofibers via melt blending or extrusion of cellulose acetate butyrate (CAB)/LDPE immiscible blends and subsequent removal of the CAB matrix. The sizes of the PE spheres or fibers can be successfully controlled by varyi...

Chemical, mineral composition, and sensory acceptability of cocoyam-based recipes enriched with cowpea flour.

PubMed

Olayiwola, Ibiyemi; Folaranmi, Funmi; Adebowale, Abdul-Rasaq A; Oluseye, Onabanjo; Ajoke, Sanni; Wasiu, Afolabi

2013-05-01

The study was conducted to improve cocoyam-based recipes (steamed cocoyam paste [ ebiripo ], ikokore, and fried cocoyam balls [ ojojo ]) using different blends of cocoyam and cowpea flours (100:0, 80:20, 70:30, 60:40, and 50:50). The proximate composition, mineral composition, and sensory qualities of the recipes were determined using standard analytical procedures. The recipes had significantly ( P  <   0.05) higher contents of protein, fat, crude fiber, iron, zinc, sodium, and phosphorus compared with the control recipe (100% cocoyam flour). The protein content was highest in all recipes containing 50:50 cocoyam: cowpea flour (10.79%, 10.56%, 10.36% for ojojo, ikokore, and ebiripo , respectively). However, ikokore had higher iron (2.5 mg), phosphorus (92.5 mg), and zinc (1.92 mg) contents than ebiripo and ojojo . While the 80:20 recipe for ebiripo had significantly ( P  <   0.05) higher flavor and overall acceptability scores compared with other recipes. In conclusion, enrichment of cocoyam-based recipes with cowpea flour improved the proximate composition, mineral composition, and sensory acceptability of the foods.

Preparation and tensile properties of linear low density polyethylene/rambutan peels (Nephelium chryseum Blum.) flour blends

NASA Astrophysics Data System (ADS)

Nadhirah, A. Ainatun.; Sam, S. T.; Noriman, N. Z.; Voon, C. H.; Samera, S. S.

2015-05-01

The effect of rambutan peels flour (RPF) content on the tensile properties of linear low density polyethylene filled with rambutan peel flour was studied. RPF was melt blended with linear low-density polyethylene (LLDPE). LLDPE/RPF blends were prepared by using internal mixer (brabender) at 160 °C with the flour content ranged from 0 to 15 wt%. The tensile properties were tested by using a universal testing machine (UTM) according to ASTM D638. The highest tensile strength was observed for pure LLDPE while the tensile strength LLDPE/RPF decreased gradually with the addition of rambutan peels flour content from 0% to 15%. Young's modulus of 63 µm to 250 µm rambutan peels blends with LLDPE with the fiber loading of 0 - 15 wt% increased with increasing fiber loading.

Glycemic index and microstructure analysis of a newly developed fiber enriched cookie.

PubMed

Schuchardt, Jan Philipp; Wonik, Jasmin; Bindrich, Ute; Heinemann, Michaela; Kohrs, Heike; Schneider, Inga; Möller, Katharina; Hahn, Andreas

2016-01-01

A diet with a high glycemic index (GI) is associated with an elevated risk for obesity or type 2 diabetes. We investigated the GI of a newly-developed fiber enriched cookie and characterized the microstructure of ingredients used. In a study with 26 non-diabetic healthy volunteers it was shown that the fiber enriched cookie has a GI of 58.9 in relation to white bread as reference. Using a conversion factor of 1.4, the GI of the fiber enriched cookie in relation to a glucose-solution is 42.0 and can be classified as a low-GI food. Postprandial insulin concentration was significantly lower after consumption of fiber enriched cookies compared to white bread. Glucose release after in vitro digestion was significantly lower from fiber enriched cookies compared to other cookies tested. In addition to its high percentage of fiber, the cookies' low GI can be attributed to the limited gelatinization potential of the starch granules found in the ingredients used. Using confocal laser scanning microscopy it is shown that starch granule surface area of whole grain barley flour, spelt flour and oat flakes bears cluster-shaped protein-NSPS complexes that preferentially absorb water in conditions of water shortage and thereby prevent starch gelatinization.

Engineering Design Handbook. Discontinuous Fiberglass Reinforced Thermoplastics

DTIC Science & Technology

1981-04-01

Fiberglass Type and Form Glass fibers are...Hall, Ltd. Figure 2-11. Stress vs Volume of Glass Fiber for Nylon and Polypropylene Glass Fiber E glass 12 Mm diam. Fibreglass Ltd Size ref...good dispersion of fiberglass in the end product with pelletized feed stocks. Glass fiber attrition is minimized with the dry blend technique,

Economical concrete mix design utilizing blended cements, performance-based specifications, and pay factors.

DOT National Transportation Integrated Search

2013-05-01

This report showcases several new approaches of using materials science and structural mechanics to accomplish : sustainable design of concrete materials. The topics addressed include blended cements, fiber-reinforced concrete : (FRC), internal curin...

Biohybrid Fibro-Porous Vascular Scaffolds: Effect of Crosslinking on Properties

PubMed Central

Nozik, Danna; Patel, Harsh; Singh, Raj K.; Vohra, Yogesh K.

2015-01-01

Tubular grafts were fabricated from blends of polycaprolactone (PCL) and poly(glycolide -co-caprolactone) (PGC) polymers and coated with an extracellular matrix containing collagens, laminin, and proteoglycans, but not growth factors (HuBiogel™). Multifunctional scaffolds from polymer blends and membrane proteins provide the necessary biomechanics and biological functions for tissue regeneration. Two crosslinking agents, a natural crosslinker namely genipin (Gp) and a carbodiimide reagent namely 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), were used for further stabilizing the protein matrix and the effect of crosslinking was evaluated for structural, morphological, mechanical properties using SEM, DSC and DMA. SEM images and fiber diameter distribution showed fiber-size between 0.2 µm to 1 µm with the majority of fiber diameters being under 500 nm, indicating upper range of protein fiber-sizes (for example, collagen fibers in extracellular matrix are in 50 to 500 nm diameter range). HB coating did not affect the mechanical properties, but increased its hydrophilicity of the graft. Overall data showed that PCL/PGC blends with 3:1 mass ratio exhibited mechanical properties comparable to those of human native arteries (tensile strength of 1–2 MPa and Young’s modulus of <10 MPa). Additionally, the effect of crosslinking on coating stability was investigated to assure the retention of proteins on scaffold for effective cell-matrix interactions. PMID:26082566

Biohybrid Fibro-Porous Vascular Scaffolds: Effect of Crosslinking on Properties.

PubMed

Thomas, Vinoy; Nozik, Danna; Patel, Harsh; Singh, Raj K; Vohra, Yogesh K

Tubular grafts were fabricated from blends of polycaprolactone (PCL) and poly(glycolide -co-caprolactone) (PGC) polymers and coated with an extracellular matrix containing collagens, laminin, and proteoglycans, but not growth factors (HuBiogel™). Multifunctional scaffolds from polymer blends and membrane proteins provide the necessary biomechanics and biological functions for tissue regeneration. Two crosslinking agents, a natural crosslinker namely genipin (Gp) and a carbodiimide reagent namely 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), were used for further stabilizing the protein matrix and the effect of crosslinking was evaluated for structural, morphological, mechanical properties using SEM, DSC and DMA. SEM images and fiber diameter distribution showed fiber-size between 0.2 µm to 1 µm with the majority of fiber diameters being under 500 nm, indicating upper range of protein fiber-sizes (for example, collagen fibers in extracellular matrix are in 50 to 500 nm diameter range). HB coating did not affect the mechanical properties, but increased its hydrophilicity of the graft. Overall data showed that PCL/PGC blends with 3:1 mass ratio exhibited mechanical properties comparable to those of human native arteries (tensile strength of 1-2 MPa and Young's modulus of <10 MPa). Additionally, the effect of crosslinking on coating stability was investigated to assure the retention of proteins on scaffold for effective cell-matrix interactions.

[Supplementation of wheat flour with chickpea (Cicer arietinum) flour. I. Preparation of flours and their properties for bread making].

PubMed

Figuerola, F E; Estévez, A M; Castillo, E

1987-06-01

The feasibility of adding chick-pea flour substituting part of wheat flour in yeast-leavened bread-making in order to increase the protein value, was studied. A 70% extraction chick-pea flour of commercial granulometry (150 mu) was prepared. Wheat flours of 74% and 78% extraction were then blended with 5%, 10% and 15% of chick-pea flour. Every flour and blend were subsequently analyzed to determine protein, ash, fiber, fat and maltose content, as well as sedimentation, farinogram and bread-making. Addition of chick-pea flour increased protein, fiber, ash and fat content in the blends, not causing a severe effect on quality, even at the 15% level of substitution. Blends showed an increase in maltose content, W value and bread specific volume. Furthermore, breads prepared were of good quality even without the use of maturing agents.

Green Composites Based on Blends of Polypropylene with Liquid Wood Reinforced with Hemp Fibers: Thermomechanical Properties and the Effect of Recycling Cycles.

PubMed

Cicala, Gianluca; Tosto, Claudio; Latteri, Alberta; La Rosa, Angela Daniela; Blanco, Ignazio; Elsabbagh, Ahmed; Russo, Pietro; Ziegmann, Gerhard

2017-08-26

Green composites from polypropylene and lignin-based natural material were manufactured using a melt extrusion process. The lignin-based material used was the so called "liquid wood". The PP/"Liquid Wood" blends were extruded with "liquid wood" content varying from 20 wt % to 80 wt %. The blends were thoroughly characterized by flexural, impact, and dynamic mechanical testing. The addition of the Liquid Wood resulted in a great improvement in terms of both the flexural modulus and strength but, on the other hand, a reduction of the impact strength was observed. For one blend composition, the composites reinforced with hemp fibers were also studied. The addition of hemp allowed us to further improve the mechanical properties. The composite with 20 wt % of hemp, subjected to up to three recycling cycles, showed good mechanical property retention and thermal stability after recycling.

Green Composites Based on Blends of Polypropylene with Liquid Wood Reinforced with Hemp Fibers: Thermomechanical Properties and the Effect of Recycling Cycles

PubMed Central

Latteri, Alberta; La Rosa, Angela Daniela; Elsabbagh, Ahmed; Ziegmann, Gerhard

2017-01-01

Green composites from polypropylene and lignin-based natural material were manufactured using a melt extrusion process. The lignin-based material used was the so called “liquid wood”. The PP/“Liquid Wood” blends were extruded with “liquid wood” content varying from 20 wt % to 80 wt %. The blends were thoroughly characterized by flexural, impact, and dynamic mechanical testing. The addition of the Liquid Wood resulted in a great improvement in terms of both the flexural modulus and strength but, on the other hand, a reduction of the impact strength was observed. For one blend composition, the composites reinforced with hemp fibers were also studied. The addition of hemp allowed us to further improve the mechanical properties. The composite with 20 wt % of hemp, subjected to up to three recycling cycles, showed good mechanical property retention and thermal stability after recycling. PMID:28846607

Sensory evaluation of biscuits enriched with artichoke fiber-rich powders (Cynara scolymus L.).

PubMed

San José, Francisco J; Collado-Fernández, Montserrat; López, Rafael

2018-01-01

The artichoke by-products from the canning industry are mainly used for silage, being minimally revaluated. The ways of extraction of by-products of artichoke into fiber-rich powders modify their industrial applications in biscuits, as the sensory evaluation may change compared with the reference fiber (Pea fiber, P) used with commercial biscuit. In this sensory study biscuits enriched with fiber-rich powders of artichoke (W, Ca) are compared with biscuits with the same percentage of the reference fiber (P) and control biscuits without fiber (B). For most of the sensory attributes of the biscuits enriched with artichoke fiber-rich powders were perceived similar to the biscuits with the commercial reference fiber (P). The good sensory behavior of the biscuits with artichoke fiber-rich powders during two storage conditions applied may confirm that the artichoke by-products would be a suitable substitute for pea fiber in oven-baked products, like wholemeal biscuits with high-fiber content.

Flame retardant antibacterial cotton high-loft nonwoven fabrics

USDA-ARS?s Scientific Manuscript database

Flame retardant treated gray cotton fibers were blended with antibacterial treated gray cotton fibers and polyester/polyester sheath/core bicomponent fibers to form high-loft fabrics. The high flame retardancy (FR) and antibacterial property of these high lofts were evaluated by limiting oxygen inde...

Technical solutions to nonproliferation challenges

NASA Astrophysics Data System (ADS)

Satkowiak, Lawrence

2014-05-01

The threat of nuclear terrorism is real and poses a significant challenge to both U.S. and global security. For terrorists, the challenge is not so much the actual design of an improvised nuclear device (IND) but more the acquisition of the special nuclear material (SNM), either highly enriched uranium (HEU) or plutonium, to make the fission weapon. This paper provides two examples of technical solutions that were developed in support of the nonproliferation objective of reducing the opportunity for acquisition of HEU. The first example reviews technologies used to monitor centrifuge enrichment plants to determine if there is any diversion of uranium materials or misuse of facilities to produce undeclared product. The discussion begins with a brief overview of the basics of uranium processing and enrichment. The role of the International Atomic Energy Agency (IAEA), its safeguard objectives and how the technology evolved to meet those objectives will be described. The second example focuses on technologies developed and deployed to monitor the blend down of 500 metric tons of HEU from Russia's dismantled nuclear weapons to reactor fuel or low enriched uranium (LEU) under the U.S.-Russia HEU Purchase Agreement. This reactor fuel was then purchased by U.S. fuel fabricators and provided about half the fuel for the domestic power reactors. The Department of Energy established the HEU Transparency Program to provide confidence that weapons usable HEU was being blended down and thus removed from any potential theft scenario. Two measurement technologies, an enrichment meter and a flow monitor, were combined into an automated blend down monitoring system (BDMS) and were deployed to four sites in Russia to provide 24/7 monitoring of the blend down. Data was downloaded and analyzed periodically by inspectors to provide the assurances required.

Technical solutions to nonproliferation challenges

DOE Office of Scientific and Technical Information (OSTI.GOV)

Satkowiak, Lawrence

2014-05-09

The threat of nuclear terrorism is real and poses a significant challenge to both U.S. and global security. For terrorists, the challenge is not so much the actual design of an improvised nuclear device (IND) but more the acquisition of the special nuclear material (SNM), either highly enriched uranium (HEU) or plutonium, to make the fission weapon. This paper provides two examples of technical solutions that were developed in support of the nonproliferation objective of reducing the opportunity for acquisition of HEU. The first example reviews technologies used to monitor centrifuge enrichment plants to determine if there is any diversionmore » of uranium materials or misuse of facilities to produce undeclared product. The discussion begins with a brief overview of the basics of uranium processing and enrichment. The role of the International Atomic Energy Agency (IAEA), its safeguard objectives and how the technology evolved to meet those objectives will be described. The second example focuses on technologies developed and deployed to monitor the blend down of 500 metric tons of HEU from Russia's dismantled nuclear weapons to reactor fuel or low enriched uranium (LEU) under the U.S.-Russia HEU Purchase Agreement. This reactor fuel was then purchased by U.S. fuel fabricators and provided about half the fuel for the domestic power reactors. The Department of Energy established the HEU Transparency Program to provide confidence that weapons usable HEU was being blended down and thus removed from any potential theft scenario. Two measurement technologies, an enrichment meter and a flow monitor, were combined into an automated blend down monitoring system (BDMS) and were deployed to four sites in Russia to provide 24/7 monitoring of the blend down. Data was downloaded and analyzed periodically by inspectors to provide the assurances required.« less

Isolation and recovery of cellulose from waste nylon/cotton blended fabrics by 1-allyl-3-methylimidazolium chloride.

PubMed

Lv, Fangbing; Wang, Chaoxia; Zhu, Ping; Zhang, Chuanjie

2015-06-05

Development of a simple process for separating cellulose and nylon 6 from their blended fabrics is indispensable for recycling of waste mixed fabrics. An efficient procedure of dissolution of the fabrics in an ionic liquid 1-allyl-3-methylimidazolium chloride ([AMIM]Cl) and subsequent filtration separation has been demonstrated. Effects of treatment temperature, time and waste fabrics ratio on the recovery rates were investigated. SEM images showed that the cotton cellulose dissolved in [AMIM]Cl while the nylon 6 fibers remained. The FTIR spectrum of regenerated cellulose (RC) was similar with that of virgin cotton fibers, which verified that no other chemical reaction occurred besides breakage of hydrogen bonds during the processes of dissolution and separation. TGA curves indicated that the regenerated cellulose possessed a reduced thermal stability and was effectively removed from waste nylon/cotton blended fabrics (WNCFs). WNCFs were sufficiently reclaimed with high recovery rate of both regenerated cellulose films and nylon 6 fibers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Closing the Achievement Gap with Curriculum Enrichment and Differentiation: One School's Story

ERIC Educational Resources Information Center

Beecher, Margaret; Sweeny, Sheelah M.

2008-01-01

This article summarizes a unique approach to reducing the achievement gap that strategically blended differentiated curriculum with schoolwide enrichment teaching and learning. The theories of enrichment and instructional differentiation were translated into practice in an elementary school that had previously embraced a remedial paradigm. This…

Effects of chemical versus enzymatic processing of kenaf fibers on poly(hydroxybutyrate-co-valerate)/poly(butylene adipate-co-terephthalate) composite properties

USDA-ARS?s Scientific Manuscript database

The effect of fiber retting on crystallization and mechanical performance was investigated. A poly(hydroxybutyrate-co-valerate) (PHBV) and poly(butylene adipate-co-terephthalate) (PBAT) blend in a 80/20 ratio was modified using 5% by weight kenaf (Hibiscus cannabinus L.) fiber. Fibers were retted us...

Nutritional evaluation of structured lipid containing omega 6 fatty acid synthesized from coconut oil in rats.

PubMed

Rao, Reena; Lokesh, Belur R

2003-06-01

Coconut oil is rich in medium chain fatty acids, but deficient in polyunsaturated fatty acids (PUFA). Structured lipids (SL) enriched with omega 6 PUFA were synthesized from coconut oil triglycerides by employing enzymatic acidolysis with free fatty acids obtained from safflower oil. Rats were fed a diet containing coconut oil, coconut oil-safflower oil blend (1:0.7 w/ w) or structured lipid at 10% levels for a period of 60 days. The SL lowered serum cholesterol levels by 10.3 and 10.5% respectively in comparison with those fed coconut oil and blended oil. Similarly the liver cholesterol levels were also decreased by 35.9 and 26.6% respectively in animals fed structured lipids when compared to those fed on coconut oil or the blended oil. Most of the decrease observed in serum cholesterol levels of animals fed structured lipids was found in LDL fraction. The triglyceride levels in serum showed a decrease by 17.5 and 17.4% while in the liver it was reduced by 45.8 and 23.5% in the structured lipids fed animals as compared to those fed coconut oil or blended oil respectively. Differential scanning calorimetric studies indicated that structured lipids had lower melting points and solid fat content when compared to coconut oil or blended oils. These studies indicated that enrichment of coconut oil triglycerides with omega 6 fatty acids lowers its solid fat content. The omega 6 PUFA enriched structured lipids also exhibited hypolipidemic activity.

New beverages of lemon juice enriched with the exotic berries maqui, açaı́, and blackthorn: bioactive components and in vitro biological properties.

PubMed

Gironés-Vilaplana, Amadeo; Valentão, Patrícia; Moreno, Diego A; Ferreres, Federico; García-Viguera, Cristina; Andrade, Paula B

2012-07-04

Following previous research on lemon juice enriched with berries, the aim of this work was to design new blends based on lemon juice mixed with different edible berries of exotic and national origin: maqui ( Aristotelia chilensis (Molina) Stuntz), açaı́ ( Euterpe oleracea Mart.), and blackthorn ( Prunus spinosa L.). The phytochemical characterization of controls and blends was performed by HPLC-DAD-ESI/MS(n). Their antioxidant capacity against DPPH, superoxide, and hydroxyl radicals and hypochlorous acid and their potential to inhibit cholinesterases were also assessed. The profiling of the red fruits and lemon revealed a wide range of bioactive phenolics. The novel beverage based on lemon juice and maqui berry (LM) was the most interesting blend in terms of antioxidant capacity. Berry control samples displayed reduced effects on acetylcholinesterase and butyrylcholinesterase, the lemon juice control being always the most active. This activity was also remarkable for lemon-blackthorn (LB) and lemon-açaı́ (LA) blends, the last being the most effective inhibitor of cholinesterases among all samples. The results suggested that lemon juice enriched with berries could be of potential interest in the design of new drinks with a nutritive related function on health for chronic diseases.

Well-conditioning global-local analysis using stable generalized/extended finite element method for linear elastic fracture mechanics

NASA Astrophysics Data System (ADS)

Malekan, Mohammad; Barros, Felicio Bruzzi

2016-11-01

Using the locally-enriched strategy to enrich a small/local part of the problem by generalized/extended finite element method (G/XFEM) leads to non-optimal convergence rate and ill-conditioning system of equations due to presence of blending elements. The local enrichment can be chosen from polynomial, singular, branch or numerical types. The so-called stable version of G/XFEM method provides a well-conditioning approach when only singular functions are used in the blending elements. This paper combines numeric enrichment functions obtained from global-local G/XFEM method with the polynomial enrichment along with a well-conditioning approach, stable G/XFEM, in order to show the robustness and effectiveness of the approach. In global-local G/XFEM, the enrichment functions are constructed numerically from the solution of a local problem. Furthermore, several enrichment strategies are adopted along with the global-local enrichment. The results obtained with these enrichments strategies are discussed in detail, considering convergence rate in strain energy, growth rate of condition number, and computational processing. Numerical experiments show that using geometrical enrichment along with stable G/XFEM for global-local strategy improves the convergence rate and the conditioning of the problem. In addition, results shows that using polynomial enrichment for global problem simultaneously with global-local enrichments lead to ill-conditioned system matrices and bad convergence rate.

Enrichment of light hydrocarbon mixture

DOEpatents

Yang, Dali [Los Alamos, NM; Devlin, David [Santa Fe, NM; Barbero, Robert S [Santa Cruz, NM; Carrera, Martin E [Naperville, IL; Colling, Craig W [Warrenville, IL

2011-11-29

Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

Enrichment of light hydrocarbon mixture

DOEpatents

Yang,; Dali, [Los Alamos, NM; Devlin, David [Santa Fe, NM; Barbero, Robert S [Santa Cruz, NM; Carrera, Martin E [Naperville, IL; Colling, Craig W [Warrenville, IL

2010-08-10

Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

Fibrous scaffolds fabricated by emulsion electrospinning: from hosting capacity to in vivo biocompatibility

NASA Astrophysics Data System (ADS)

Spano, F.; Quarta, A.; Martelli, C.; Ottobrini, L.; Rossi, R. M.; Gigli, G.; Blasi, L.

2016-04-01

Electrospinning is a versatile method for preparing functional three-dimensional scaffolds. Synthetic and natural polymers have been used to produce micro- and nanofibers that mimic extracellular matrices. Here, we describe the use of emulsion electrospinning to prepare blended fibers capable of hosting aqueous species and releasing them in solution. The existence of an aqueous and a non-aqueous phase allows water-soluble molecules to be introduced without altering the structure and the degradation of the fibers, and means that their release properties under physiological conditions can be controlled. To demonstrate the loading capability and flexibility of the blend, various species were introduced, from magnetic nanoparticles and quantum rods to biological molecules. Cellular studies showed the spontaneous adhesion and alignment of cells along the fibers. Finally, in vivo experiments demonstrated the high biocompatibility and safety of the scaffolds up to 21 days post-implantation.Electrospinning is a versatile method for preparing functional three-dimensional scaffolds. Synthetic and natural polymers have been used to produce micro- and nanofibers that mimic extracellular matrices. Here, we describe the use of emulsion electrospinning to prepare blended fibers capable of hosting aqueous species and releasing them in solution. The existence of an aqueous and a non-aqueous phase allows water-soluble molecules to be introduced without altering the structure and the degradation of the fibers, and means that their release properties under physiological conditions can be controlled. To demonstrate the loading capability and flexibility of the blend, various species were introduced, from magnetic nanoparticles and quantum rods to biological molecules. Cellular studies showed the spontaneous adhesion and alignment of cells along the fibers. Finally, in vivo experiments demonstrated the high biocompatibility and safety of the scaffolds up to 21 days post-implantation. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00782a

In vitro fermentation characteristics of novel fibers, coconut endosperm fiber and chicory pulp, using canine fecal inoculum.

PubMed

de Godoy, M R C; Mitsuhashi, Y; Bauer, L L; Fahey, G C; Buff, P R; Swanson, K S

2015-01-01

The objective of this experiment was to determine the effects of in vitro fermentation of coconut endosperm fiber (CEF), chicory pulp (CHP), and selective blends of these substrates on SCFA production and changes in microbiota using canine fecal inocula. A total of 6 individual substrates, including short-chain fructooligosaccharide (scFOS; a well-established prebiotic source), pectin (PEC; used as a positive control), pelletized cellulose (PC; used as a negative control), beet pulp (BP; considered the gold standard fiber source in pet foods), CEF, and CHP, and 3 CEF:CHP blends (75:25% CEF:CHP [B1], 50:50% CEF:CHP [B2], and 25:75% CEF:CHP [B3]) were tested. Triplicate samples of each substrate were fermented for 0, 8, and 16 h after inoculation. A significant substrate × time interaction (P < 0.05) was observed for pH change and acetate, propionate, butyrate, and total SCFA concentrations. After 8 and 16 h, pH change was greatest for scFOS (-2.0 and -3.0, respectively) and smallest for PC (0.0 and -0.1, respectively). After 16 h, CEF had a greater butyrate concentration than CHP and all the CEF:CHP blends and it was not different than PEC. The substrate × time interaction was significant for bifidobacteria (P < 0.05) and lactobacilli (P < 0.05). After 8 h, bifidobacteria was greatest for BP and lowest for PC (12.7 and 10.0 log10 cfu/tube, respectively). After 16 h, PC had the lowest and scFOS had the greatest bifidobacteria (6.7 and 13.3 log10 cfu/tube, respectively). In general, CEF, CHP, and their blends had similar bifidobacteria populations after 8 and 16 h of fermentation when compared with BP and scFOS. After 16 h, lactobacilli populations were greatest for B1, B2, B3, BP, and scFOS, intermediate for PEC, and lowest for PC (P < 0.05). Overall, our data suggest that CEF had a butyrogenic effect and that CEF, CHP, and their blends had similar bifidobacteria and lactobacilli populations as popular prebiotic and fiber substrates. Future research should investigate the effects of CEF, CHP, and their blends on gastrointestinal health and fecal quality in dogs.

Activated carbon fibers and engineered forms from renewable resources

DOEpatents

Baker, Frederick S

2013-02-19

A method of producing activated carbon fibers (ACFs) includes the steps of providing a natural carbonaceous precursor fiber material, blending the carbonaceous precursor material with a chemical activation agent to form chemical agent-impregnated precursor fibers, spinning the chemical agent-impregnated precursor material into fibers, and thermally treating the chemical agent-impregnated precursor fibers. The carbonaceous precursor material is both carbonized and activated to form ACFs in a single step. The method produces ACFs exclusive of a step to isolate an intermediate carbon fiber.

Activated carbon fibers and engineered forms from renewable resources

DOEpatents

Baker, Frederick S.

2010-06-01

A method of producing activated carbon fibers (ACFs) includes the steps of providing a natural carbonaceous precursor fiber material, blending the carbonaceous precursor material with a chemical activation agent to form chemical agent-impregnated precursor fibers, spinning the chemical agent-impregnated precursor material into fibers, and thermally treating the chemical agent-impregnated precursor fibers. The carbonaceous precursor material is both carbonized and activated to form ACFs in a single step. The method produces ACFs exclusive of a step to isolate an intermediate carbon fiber.

Effect of clay content on morphology and processability of electrospun keratin/poly(lactic acid) nanofiber.

PubMed

Isarankura Na Ayutthaya, Siriorn; Tanpichai, Supachok; Sangkhun, Weradesh; Wootthikanokkhan, Jatuphorn

2016-04-01

This research work has concerned the development of volatile organic compounds (VOCs) removal filters from biomaterials, based on keratin extracted from chicken feather waste and poly(lactic acid) (PLA) (50/50%w/w) blend. Clay (Na-montmorillonite) was also added to the blend solution prior to carrying out an electro-spinning process. The aim of this study was to investigate the effect of clay content on viscosity, conductivity, and morphology of the electrospun fibers. Scanning electron micrographs showed that smooth and bead-free fibers were obtained when clay content used was below 2 pph. XRD patterns of the electrospun fibers indicated that the clay was intercalated and exfoliated within the polymers matrix. Percentage crystallinity of keratin in the blend increased after adding the clay, as evidenced from FTIR spectra and DSC thermograms. Transmission electron micrographs revealed a kind of core-shell structure with clay being predominately resided within the keratin rich shell and at the interfacial region. Filtration performance of the electrospun keratin/PLA fibers, described in terms of pressure drop and its capability of removing methylene blue, were also explored. Overall, our results demonstrated that it was possible to improve process-ability, morphology and filtration efficiency of the electrospun keratin fibers by adding a suitable amount of clay. Copyright © 2016 Elsevier B.V. All rights reserved.

Implication of processing and differential blending on quality characteristics in nutritionally enriched ketchup (Nutri-Ketchup) from acerola and tomato.

PubMed

Prakash, Anand; Prabhudev, S H; Vijayalakshmi, M R; Prakash, Maya; Baskaran, Revathy

2016-08-01

The present study was focused on the development of nutritionally enriched ketchup (Nutri-ketchup) from acerola and tomato and evaluation of the effect of blending and processing on physicochemical characteristics, phytonutrients retention, antioxidant activity and sensorial quality. Acerola and tomato pulps blended in various ratios viz. 100:0, 75:25, 50:50, 25:75 and 0:100 were used for the preparation of five formulations of ketchup and compared with commercially available tomato ketchup. The retention of phytonutrients varied among formulations viz. ascorbic acid- ~18-29 %, anthocyanins- ~17-25 %, phenolics- ~11-70 %, flavonoids- ~24-42 %, lycopene- ~24-33 % and carotenoids- ~23-34 %. Antioxidant capacity of 80 % methanol extract and ascorbic acid fraction of the formulations evaluated using DPPH and ABTS assays showed higher activity than the commercial sample. Ketchup prepared from acerola and tomato blend of 75:25 showed the best overall quality, while all the other formulations were also sensorily acceptable.

Effect of Cold-Drawn Fibers on the Self-Reinforcement of PP/LDPE Composites

NASA Astrophysics Data System (ADS)

Zhou, Ying-Guo; Su, Bei; Wu, Hai-Hong

2017-08-01

In our previous study, a method to fabricate super-ductile polypropylene/low-density polyethylene (PP/LDPE) blends was proposed, and a fiber-shape structure was shown to be formed, presenting necking propagation during tensile testing. In this study, the mechanical properties and thermal behavior of the necking region of tested super-ductile PP/LDPE samples were carefully investigated and further compared with the melt-stretched, untested, and thermo-mechanical-history-removed samples by differential scanning calorimetry and tensile testing. The results suggest that the tested samples have high mechanical properties and are more thermo-mechanically stable than the common PP/LDPE blends and melt-stretched samples. Additionally, to investigate their structure-property relationship, the necking region of the tested samples was further characterized by scanning electron microscopy and hot-stage polarized light microscopy. It can be concluded that the variation of the microstructure can be attributed to the cold-drawn fibers (CDFs), which were more stable thermally, formed during the tensile test. Furthermore, the CDFs were used for the filler in PP/LDPE blends. The experimental results of the different PP/LDPE composites indicate that the CDFs are a good reinforcement candidate and have the ability to improve the mechanical properties of the PP/LDPE blends.

Color matching of fabric blends: hybrid Kubelka-Munk + artificial neural network based method

NASA Astrophysics Data System (ADS)

Furferi, Rocco; Governi, Lapo; Volpe, Yary

2016-11-01

Color matching of fabric blends is a key issue for the textile industry, mainly due to the rising need to create high-quality products for the fashion market. The process of mixing together differently colored fibers to match a desired color is usually performed by using some historical recipes, skillfully managed by company colorists. More often than desired, the first attempt in creating a blend is not satisfactory, thus requiring the experts to spend efforts in changing the recipe with a trial-and-error process. To confront this issue, a number of computer-based methods have been proposed in the last decades, roughly classified into theoretical and artificial neural network (ANN)-based approaches. Inspired by the above literature, the present paper provides a method for accurate estimation of spectrophotometric response of a textile blend composed of differently colored fibers made of different materials. In particular, the performance of the Kubelka-Munk (K-M) theory is enhanced by introducing an artificial intelligence approach to determine a more consistent value of the nonlinear function relationship between the blend and its components. Therefore, a hybrid K-M+ANN-based method capable of modeling the color mixing mechanism is devised to predict the reflectance values of a blend.

Multi-Length Scale-Enriched Continuum-Level Material Model for Kevlar-Fiber-Reinforced Polymer-Matrix Composites

DTIC Science & Technology

2012-08-03

is unlimited. Multi-Length Scale-Enriched Continuum-Level Material Model for Kevlar ®-Fiber-Reinforced Polymer-Matrix Composites The views, opinions...12211 Research Triangle Park, NC 27709-2211 ballistics, composites, Kevlar , material models, microstructural defects REPORT DOCUMENTATION PAGE 11... Kevlar ®-Fiber-Reinforced Polymer-Matrix Composites Report Title Fiber-reinforced polymer matrix composite materials display quite complex deformation

16 CFR 303.6 - Generic names of fibers to be used.

Code of Federal Regulations, 2010 CFR

2010-01-01

... hair or fiber of a fur-bearing animal present in the amount 5 per centum or more of the total fiber... required information, provided the name of such animal is used in conjunction with the words “fiber,” “hair,” or “blend;” as for example: 80 percent Rabbit hair. 20 percent Nylon. or 80 percent Silk. 20 percent...

16 CFR 303.6 - Generic names of fibers to be used.

Code of Federal Regulations, 2014 CFR

2014-01-01

... hair or fiber of a fur-bearing animal present in the amount 5 per centum or more of the total fiber... required information, provided the name of such animal is used in conjunction with the words “fiber,” “hair,” or “blend;” as for example: 80 percent Rabbit hair. 20 percent Nylon. or 80 percent Silk. 20 percent...

16 CFR 303.6 - Generic names of fibers to be used.

Code of Federal Regulations, 2013 CFR

2013-01-01

... hair or fiber of a fur-bearing animal present in the amount 5 per centum or more of the total fiber... required information, provided the name of such animal is used in conjunction with the words “fiber,” “hair,” or “blend;” as for example: 80 percent Rabbit hair. 20 percent Nylon. or 80 percent Silk. 20 percent...

16 CFR 303.6 - Generic names of fibers to be used.

Code of Federal Regulations, 2011 CFR

2011-01-01

... hair or fiber of a fur-bearing animal present in the amount 5 per centum or more of the total fiber... required information, provided the name of such animal is used in conjunction with the words “fiber,” “hair,” or “blend;” as for example: 80 percent Rabbit hair. 20 percent Nylon. or 80 percent Silk. 20 percent...

16 CFR 303.6 - Generic names of fibers to be used.

Code of Federal Regulations, 2012 CFR

2012-01-01

... hair or fiber of a fur-bearing animal present in the amount 5 per centum or more of the total fiber... required information, provided the name of such animal is used in conjunction with the words “fiber,” “hair,” or “blend;” as for example: 80 percent Rabbit hair. 20 percent Nylon. or 80 percent Silk. 20 percent...

Development program to produce mullite fiber insulation

NASA Technical Reports Server (NTRS)

Long, W. G.

1975-01-01

Processing methods were utilized to form a mullite fiber-Kaowool felt. The formation of a blended felt using the Rotoformer wet-laying method was successful. Felt products were evaluated for tensile strength, thermal stability, thermal conductivity and structural integrity at 1259 C and 1371 C. Textile processing methods failed in an attempt to form a yarn from staple and multifilament mullite fiber due to fiber damage through mechanical handling. The refractoriness of pure Kaowool ceramic fiber is improved with additions of 30% or greater mullite fiber.

Challenges for Collaborative Blended Learning in Undergraduate Students

ERIC Educational Resources Information Center

Monteiro, Elisa; Morrison, Keith

2014-01-01

This study reports a quasi-experiment in collaborative blended learning (CBL) with undergraduate students who, despite being in a world-leading, enriched digital environment, were new to collaboration and CBL. The mixed-methods research found that only small improvements to students' CBL took place over time, and explanations for this are…

Effects of addition of different fibers on rheological characteristics of cake batter and quality of cakes.

PubMed

Aydogdu, Ayca; Sumnu, Gulum; Sahin, Serpil

2018-02-01

The aim of this study was to investigate the effects of addition of dietary fibers on rheological properties of batter and cake quality. Wheat flour was replaced by 5 and 10% (wt%) oat, pea, apple and lemon fibers. All cake batters showed shear thinning behavior. Incorporation of fibers increased consistency index (k), storage modulus (G') and loss modulus (G″). As quality parameters, specific volume, hardness, weight loss, color and microstructure of cakes were investigated. Cakes containing oat and pea fibers (5%) had similar specific volume and texture with control cakes which contained no fiber. As fiber concentration increased, specific volume decreased but hardness increased. No significant difference was found between weight loss of control cake and cakes with oat, pea and apple fibers. Lemon fiber enriched cakes had the lowest specific volume, weight loss and color difference. When microstructural images were examined, it was seen that control cake had more porous structure than fiber enriched cakes. In addition, lemon and apple fiber containing cakes had less porous crumb structure as compared to oat and pea containing ones. Oat and pea fiber (5%) enriched cakes had similar physical properties (volume, texture and color) with control cakes.

Blueberry by-product used as an ingredient in the development of functional cookies.

PubMed

Perez, Claudia; Tagliani, Camila; Arcia, Patricia; Cozzano, Sonia; Curutchet, Ana

2018-06-01

A by-product of blueberry juice industries was used as an ingredient to develop fiber-enriched cookies. The blueberry pomace, once ground and dried, was used as an ingredient in cookie formulation. A control cookie was elaborated as reference. Cookies were analyzed for composition and functional properties. The fiber content obtained in the fiber-enriched cookie allows it to be labeled as "high fiber" in the European Union and as a "source of fiber" in MERCOSUR. The fiber-enriched cookie presented highly increased values on the antioxidant capacity and the polyphenol content when compared against the control cookie. Sensory evaluation was performed. Acceptability of the fiber-enriched cookie reached a value of 5.3 in a nine-point hedonic scale. Further strategies should be necessary in order to achieve an acceptable product. Cookies were subjected to an in vitro digestive process. Results show that the cookies' phytochemicals are bioaccessible and potentially bioavailable. Therefore, eating this type of food would represent an increase in the amount of antioxidants ingested and redound to a health benefit. In addition to improving both nutritional and functional properties of cookies, the present development represents an innovative strategy for a more sustainable growth of fruit juice industries.

Multi-Length Scale-Enriched Continuum-Level Material Model for Kevlar (registered trademark)-Fiber-Reinforced Polymer-Matrix Composites

DTIC Science & Technology

2013-03-01

of coarser-scale materials and structures containing Kevlar fibers (e.g., yarns, fabrics, plies, lamina, and laminates ). Journal of Materials...Multi-Length Scale-Enriched Continuum-Level Material Model for Kevlar -Fiber-Reinforced Polymer-Matrix Composites M. Grujicic, B. Pandurangan, J.S...extensive set of molecular-level computational analyses regarding the role of various microstructural/morphological defects on the Kevlar fiber

Process for preparing tows from composite fiber blends

NASA Technical Reports Server (NTRS)

McMahon, Paul (Inventor); Chung, Tai-Shung (Inventor); Ying, Lincoln (Inventor)

1989-01-01

A continuous, substantially uniform tow useful in forming composite molded articles is prepared by forming a continuous tow of continuous carbon fibers, forming a continuous tow of thermoplastic polymer fibers to a selected width, uniformly and continuously spreading the carbon fiber two to a width that is essentially the same as the selected width for the thermoplastic polymer fiber tow, intermixing the tows intimately, uniformly and continuously, in a relatively tension-free state, and continuosuly withdrawing the intermixed tow.

Effect of an isocaloric diet containing fiber-enriched flour on anthropometric and biochemical parameters in healthy non-obese non-diabetic subjects.

PubMed

Briganti, Silvia; Ermetici, Federica; Malavazos, Alexis E; Dozio, Elena; Giubbilini, Paola; Rigolini, Roberta; Goggi, Silvia; Morricone, Lelio; Corsi Romanelli, Massimiliano Marco

2015-11-01

We studied the effect of soluble fiber-enriched products on anthropometric and biochemical variables in 30 healthy non-obese, non-diabetic subjects. This was a randomized, controlled crossover, single-blind, dietary intervention study performed for 8 weeks. Subjects received an isocaloric diet with fiber-enriched products for the first 4 weeks and with regular flour products for the following 4 weeks, or vice versa. Weight, height, measures of fat distribution (waist, hip circumference), glucose, insulin and triglycerides were measured at baseline, after 4 and 8 weeks of intervention. BMI and insulin sensitivity indices were calculated. Weight and BMI decreased in the first period of isocaloric diet in both groups, regardless of the type of flour consumed (weight p<0.01, p<0.001 respectively; BMI p = 0.01, p<0.001 respectively). At the end of the 8 weeks, weight and BMI further decreased in the group consuming the fiber-enriched diet (p<0.01). Insulin resistance, estimated with the Homeostasis Model Assessment index and the Lipid Accumulation Product index, improved in all subjects after the fiber-enriched flour diet (p = 0.03, p = 0.02, respectively). In conclusion, an isocaloric diet supplemented with fiber-enriched products may improve measures of fatness and insulin sensitivity in healthy non-obese non-diabetic subjects. We might hypothesize a similar effect also in subjects with metabolic abnormalities.

Tailoring fiber grating sensors for assessment of highly refractive fuels.

PubMed

Kawano, Marianne Sumie; Heidemann, Bárbara Rutyna; Cardoso, Tárik Kaiel Machado; Possetti, Gustavo Rafael Collere; Kamikawachi, Ricardo Canute; Muller, Marcia; Fabris, José Luís

2012-04-20

Three approaches that allow the tailoring of long period gratings based refractometric sensors for concentration measurement in fuel blends are employed to assess the fuel quality in biodiesel and biodiesel-petrodiesel blend. To allow the analysis of fuel samples with refractive index higher than fiber cladding one, the samples refractive indices were changed by thermo-optic effect and by dilution in a standard substance with low refractive index. The obtained results show the sensor can detect oil concentration in biodiesel samples with resolution as better as 0.07% and biodiesel concentration in biodiesel-petrodiesel samples with average resolution of 0.09%.

Preparation of hydrophilic styrene maleic anhydride copolymer fibers for use in papermaking

DOEpatents

Rave, Terence W.

1979-01-01

Hydrophilic fibers may be prepared by discharging a heated and pressurized dispersion of a styrene-maleic anhydride copolymer into a zone of reduced temperature and pressure, and then modifying the fibers so produced by treatment with an aqueous admixture of selected cationic and anionic water-soluble, nitrogen-containing polymers. Blends of the hydrophilic fibers with wood pulp provide paper products having improved physical properties.

Recycled newspaper fibers as reinforcing fillers in thermoplastics. Part I, Analysis of tensile and impact properties in polypropylene

Treesearch

A. R. Sanadi; R. A. Young; C. Clemons; R. M. Rowell

1994-01-01

Recycled newspaper fibers (ONP) are potentially outstanding nonabrasive reinforcing fibers with high specific properties. In this study, a high energy thermokinetic mixer was used to mix these fibers in a polypropylene (PP) matrix, and the blends were then injection molded in order to observe the tensile and impact strengths of the composites. A 40% (weight) of ONP in...

Silsesquioxane-derived ceramic fibres

NASA Technical Reports Server (NTRS)

Hurwitz, F. I.; Farmer, S. C.; Terepka, F. M.; Leonhardt, T. A.

1991-01-01

Fibers formed from blends of silsesquioxane polymers were characterized to study the pyrolytic conversion of these precursors to ceramics. The morphology of fibers pyrolyzed to 1400 C revealed primarily amorphous glasses whose conversion to beta-SiC is a function of both blend composition and pyrolysis conditions. Formation of beta-SiC crystallites within the glassy phase is favored by higher than stoichiometric C/Si ratios, while carbothermal reduction of Si-O bonds to form SiC with loss of SiO and CO occurs at higher methyl/phenylpropyl silsesquioxane (lower C/Si) ratios. As the carbothermal reduction is assumed to be diffusion controlled, the fibers can serve as model systems to gain understanding of the silsesquioxane pyrolysis behavior, and therefore are useful in the development of polysilsesquioxane-derived ceramic matrices and coatings as well.

Efficient incorporation of silver to improve superconducting fibers

DOEpatents

Gleixner, Richard A.; LaCount, Dale F.; Finnemore, Douglas K.

1994-04-26

An improved method for the efficient incorporation of a metal such as silver in a superconducting material includes blending the metal with a high temperature superconductor or precursor powder and consolidating the same into pellets. The pellets are charged directly into a heating assembly where it is melted and heated sufficiently to a uniform temperature prior to fiberization. Droplets of the melted blend fall through a collar into a nozzle where they are subjected to a high velocity gas to break the melted material into ligaments which solidify into improved flexible fibers having the metal homogeneously dis This invention was made with Government support under a contract with the Department of Energy (DOE) and Ames Laboratory, Contract No. SC-91-225, our reference No. CRD-1272. The Government has certain rights in this invention.

Low energy consumption method for separating gaseous mixtures and in particular for medium purity oxygen production

DOEpatents

Jujasz, Albert J.; Burkhart, James A.; Greenberg, Ralph

1988-01-01

A method for the separation of gaseous mixtures such as air and for producing medium purity oxygen, comprising compressing the gaseous mixture in a first compressor to about 3.9-4.1 atmospheres pressure, passing said compressed gaseous mixture in heat exchange relationship with sub-ambient temperature gaseous nitrogen, dividing the cooled, pressurized gaseous mixture into first and second streams, introducing the first stream into the high pressure chamber of a double rectification column, separating the gaseous mixture in the rectification column into a liquid oxygen-enriched stream and a gaseous nitrogen stream and supplying the gaseous nitrogen stream for cooling the compressed gaseous mixture, removing the liquid oxygen-enriched stream from the low pressure chamber of the rectification column and pumping the liquid, oxygen-enriched steam to a predetermined pressure, cooling the second stream, condensing the cooled second stream and evaporating the oxygen-enriched stream in an evaporator-condenser, delivering the condensed second stream to the high pressure chamber of the rectification column, and heating the oxygen-enriched stream and blending the oxygen-enriched stream with a compressed blend-air stream to the desired oxygen concentration.

Single screw extrusion of apple pomace-enriched blends: Extrudate characteristics and determination of optimum processing conditions.

PubMed

Singha, Poonam; Muthukumarappan, Kasiviswanathan

2018-07-01

Response surface methodology was used to investigate the single screw extrusion of apple pomace-defatted soy flour-corn grits blends and the product properties. Five different blends at a level of 0-20% w/w apple pomace were extrusion cooked with varied barrel and die temperature (100-140℃), screw speed (100-200 rpm), and feed moisture content (14-20% wet basis). Increasing apple pomace content in the blends significantly ( P < 0.05) increased the bulk density, the total phenolic content, and the antioxidant activity of the extrudates. The expansion ratio increased with pomace inclusion level of 5% but decreased significantly ( P < 0.05) at higher levels of pomace inclusion (10-20%). Moisture content had quadratic influence on water absorption and solubility indices. Optimal extrusion cooking conditions most likely to produce apple pomace-enriched extruded snack products were at 140℃ barrel and die temperature, 20% feed moisture content, and 200 rpm screw speed. The results indicated active interaction between apple pomace and starch during expansion process.

TPS/PCL composite reinforced with treated sisal fibers: property, biodegradation and water-absorption

USDA-ARS?s Scientific Manuscript database

Sisal fibers bleached with sodium-hydroxide followed by hydrogen peroxide treatment were incorporated in a thermoplastic starch;-polycaprolactone (TPS/PCL) blend via extrusion processing and examined for their property, biodegradability and water-absorption. Scanning electron microscopy revealed wel...

Process for preparing composite articles from composite fiber blends

NASA Technical Reports Server (NTRS)

McMahon, Paul E. (Inventor); Chung, Tai-Shung (Inventor); Ying, Lincoln (Inventor)

1989-01-01

A composite article is prepared by forming a continuous tow of continuous carbon fibers, forming a continuous tow of thermoplastic polymer fibers, uniformly and continuously spreading the thermoplastic polymer fibers to a selected width, uniformly and continuously spreading the carbon fiber tow to a width that is essentially the same as the selected width for the thermoplastic polymer fiber tow, intermixing the tows intimately, uniformly and continuously, in a relatively tension-free state, continuously withdrawing the intermixed tow and applying the tow to a mold and heating the tow.

The effect of pineapple core fiber on dough rheology and the quality of mantou.

PubMed

Shiau, Sy-Yu; Wu, Ming-Yin; Liu, Yao-Ling

2015-09-01

The consumption of dietary fiber offers the health benefit of lowering the risk of many chronic diseases. Pineapple core fiber (PCF) in this study was extracted and incorporated into dough and mantou (i.e., steamed bread). The effects of PCF substitution and fiber size on textural and rheological properties of dough and mantou were evaluated by a texture analyzer. The substitution of wheat flour by PCF resulted in a stiffer and less extensible dough with or without fermentation. The hardness and gumminess of mantou significantly increased as the PCF substitution increased from 0% to 15%, but the cohesiveness, specific volume, and elasticity significantly decreased with the fiber substitution. Ten percent PCF-enriched dough and mantou with various fiber sizes had similar rheological and textural properties, except for the k 1 and k 2 values. By sensory evaluation, 5% PCF-enriched mantou and the control bread had better acceptability in texture, color, odor, and overall acceptability, compared to mantous enriched with 10% or 15% PCF. Significant correlations existed between the rheological properties of dough and textural parameters of mantou and between the sensory quality and textural parameters of mantou. Therefore, we suggest that fiber-enriched mantou can be prepared with 5% PCF substitution to increase the intake of dietary fiber and maintain the quality of mantou. Copyright © 2014. Published by Elsevier B.V.

Poly-(Epsilon-caprolactone) (PCL) and poly(hydroxy-butyrate) (PHB) blends containing seaweed fibers: Morphology and thermal-mechanical properties

USDA-ARS?s Scientific Manuscript database

Massive quantities of marine seaweed, Ulva armoricana are washed onto shores of many European countries and accumulates as waste. Attempts were made to utilize this renewable resource in hybrid composites by blending the algal biomass with biodegradable polymers such as poly(hydroxy-butyrate) and po...

Poly-(epsilon-caprolactone)(PCL) and poly(hydroxy-butyrate)(PHB) blends containing seaweed fibers: morphology and thermal-mechanical properties.

USDA-ARS?s Scientific Manuscript database

Massive quantities of marine seaweed, Ulva armoricana are washed onto shores of many European countries and accumulates as waste. Attempts were made to utilize this renewable resource in hybrid composites by blending the algal biomass with biodegradable polymers such as poly(hydroxy-butyrate) and po...

Morphology Evolution of Polypropylene in Immiscible Polymer Blends for Fabrication of Nanofibers

USDA-ARS?s Scientific Manuscript database

Immiscible blends of cellulose acetate butyrate (CAB) and isotactic polypropylenes (iPPs) with different melting index were extruded through a two-strand rod die. The extrudates were hot-drawn at the die exit at different draw ratios by controlling the drawing speed. The morphologies of iPP fibers e...

Functional properties of plantain, cowpea flours and oat fiber in extruded products

USDA-ARS?s Scientific Manuscript database

Drying effect on functional properties of two plantain and cowpea varieties and suitability of their flour blends in extruded snacks was determined. The functional and rheological behaviors of (plantain: cowpea): 90:10, 80:20, 70:30, 60:40 and 50:50 blends were evaluated. The extrusion product melt ...

Functional properties of pasta enriched with variable cereal brans.

PubMed

Kaur, Gurkirat; Sharma, Savita; Nagi, H P S; Dar, Basharat N

2012-08-01

To explore the potentiality of cereal brans for preparation of fiber enriched pasta, various cereal brans (Wheat, Rice, Barley and Oat) were added at 0, 5, 10, 15, 20 and 25 per cent to durum wheat semolina. The effect of cereal bran enrichment on the colour, cooking, sensory quality and shelf life of enriched pasta was assessed at ambient temperature. Pasta prepared with added fiber at 25 per cent level had the highest protein and dietary fiber content as compared to control. Enrichment with variable fiber sources improved the brightness of pasta, as colour of pasta enhanced significantly. Addition of cereal brans resulted an increase in the water absorption and cooking losses of pasta. This effect was dependent on the level and type of cereal brans. Significant correlation (r = 0.80) was obtained between water absorption and volume expansion in all types of bran enriched pasta. At 25 per cent level of supplementation, maximum solids were leached into cooking water. Bran enriched pasta required less cooking time for complete gelatinization of starch. Increasing level of cereal brans had significantly affected the overall acceptability of enriched pasta. Cooking quality of pasta remained constant during storage. Non significant effect of storage was found on water activity, free fatty acids. Enriched pasta (15 per cent level of wheat, rice and oat bran and 10 per cent barley bran) was highly acceptable upto 4 months of storage with respect to quality.

A comparative study of nitrogen conversion during pyrolysis of coconut fiber, its corresponding biochar and their blends with lignite.

PubMed

Liu, Zhengang; Balasubramanian, Rajasekhar

2014-01-01

In the present study, the conversion of fuel-N to HCN and NH3 was investigated during rapid pyrolysis of raw biomass (coconut fiber), its corresponding biochar and their blends with lignite within a temperature range of 600-900°C. The results showed that the raw biomass and the biochar showed totally different nitrogen partitioning between NH3 and HCN. HCN was the dominant nitrogen pollutant from pyrolysis of raw biomass, while for the biochar pyrolysis the yield of NH3 was slightly higher than that of HCN. Synergistic interactions occurred within both raw biomass/lignite and biochar/lignite blends, especially for the biochar/lignite blend, and resulted in reduced yields of HCN and NH3, decreased the total nitrogen percentage retained in the char and promoted harmless N2 formation. These findings suggest that biochar/lignite co-firing for energy production may have the enhanced benefit of reduced emissions of nitrogen pollutants than raw biomass/lignite. Copyright © 2013 Elsevier Ltd. All rights reserved.

New Green Polymeric Composites Based on Hemp and Natural Rubber Processed by Electron Beam Irradiation

PubMed Central

Stelescu, Maria-Daniela; Craciun, Gabriela; Dumitrascu, Maria

2014-01-01

A new polymeric composite based on natural rubber reinforced with hemp has been processed by electron beam irradiation and characterized by several methods. The mechanical characteristics: gel fraction, crosslink density, water uptake, swelling parameters, and FTIR of natural rubber/hemp fiber composites have been investigated as a function of the hemp content and absorbed dose. Physical and mechanical properties present a significant improvement as a result of adding hemp fibres in blends. Our experiments showed that the hemp fibers have a reinforcing effect on natural rubber similar to mineral fillers (chalk, carbon black, silica). The crosslinking rates of samples, measured using the Flory-Rehner equation, increase as a result of the amount of hemp in blends and the electron beam irradiation dose increasing. The swelling parameters of samples significantly depend on the amount of hemp in blends, because the latter have hydrophilic characteristics. PMID:24688419

New green polymeric composites based on hemp and natural rubber processed by electron beam irradiation.

PubMed

Stelescu, Maria-Daniela; Manaila, Elena; Craciun, Gabriela; Dumitrascu, Maria

2014-01-01

A new polymeric composite based on natural rubber reinforced with hemp has been processed by electron beam irradiation and characterized by several methods. The mechanical characteristics: gel fraction, crosslink density, water uptake, swelling parameters, and FTIR of natural rubber/hemp fiber composites have been investigated as a function of the hemp content and absorbed dose. Physical and mechanical properties present a significant improvement as a result of adding hemp fibres in blends. Our experiments showed that the hemp fibers have a reinforcing effect on natural rubber similar to mineral fillers (chalk, carbon black, silica). The crosslinking rates of samples, measured using the Flory-Rehner equation, increase as a result of the amount of hemp in blends and the electron beam irradiation dose increasing. The swelling parameters of samples significantly depend on the amount of hemp in blends, because the latter have hydrophilic characteristics.

Preparation of robust braid-reinforced poly(vinyl chloride) ultrafiltration hollow fiber membrane with antifouling surface and application to filtration of activated sludge solution.

PubMed

Zhou, Zhuang; Rajabzadeh, Saeid; Fang, Lifeng; Miyoshi, Taro; Kakihana, Yuriko; Matsuyama, Hideto

2017-08-01

Braid-reinforced hollow fiber membranes with high mechanical properties and considerable antifouling surface were prepared by blending poly(vinyl chloride) (PVC) with poly(vinyl chloride-co-poly(ethylene glycol) methyl ether methacrylate) (poly(VC-co-PEGMA)) copolymer via non-solvent induced phase separation (NIPS). The tensile strength of the braid-reinforced PVC hollow fiber membranes were significantly larger than those of previously reported various types of PVC hollow fiber membranes. The high interfacial bonding strength indicated the good compatibility between the coating materials and the surface of polyethylene terephthalate (PET)-braid. Owing to the surface segregation phenomena, the membrane surface PEGMA coverage increased upon increasing the poly(VC-co-PEGMA)/PVC blending ratio, resulting in higher hydrophilicities and bovine serum albumin (BSA) repulsion. To compare the fouling properties, membranes with similar PWPs were prepared by adjusting the dope solution composition to eliminate the effect of hydrodynamic conditions on the membrane fouling performance. The blend membranes surface exhibited considerable fouling resistance to the molecular adsorption from both BSA solution and activated sludge solution. In both cases, the flux recovered to almost 80% of the initial flux using only water backflush. Considering their great mechanical properties and antifouling resistance to activated sludge solution, these novel membranes show good potential for application in wastewater treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Mild pyrolysis of P3HB/Switchgrass blends for the production of bio-oil enriched with crotonic acid

USDA-ARS?s Scientific Manuscript database

The mild pyrolysis of switchgrass/poly-3-hydroxybutyrate (P3HB) blends that mimic P3HB-producing switchgrass lines was studied in a pilot scale fluidized bed reactor with the goal of simultaneously producing crotonic acid and switchgrass-based bio-oil. Factors such as pyrolysis temperature, residenc...

Encapsulated Presentation: A New Paradigm of Blended Learning

ERIC Educational Resources Information Center

Rose, Richard; Ray, Jan

2011-01-01

This article is a presentation of a new mode of blended learning whose only goal is to enrich the quality of instruction in the face-to-face classroom through the simultaneous delivery of online and face-to-face components. Encapsulated presentation is the delivery of the entire presentation phase of a lesson in the classroom by electronic methods…

Design of Personalized Blended Learning Environments Based on Web-Assisted Modelling in Science Education

ERIC Educational Resources Information Center

Çetinkaya, Murat

2016-01-01

Positive results of science teaching studies supported with the means provided by technology require the enrichment of the content of blended learning environments to provide more benefits. Within this context, it is thought that preparing a web-assisted model-based teaching, which is frequently used in science teaching, based on the "Matter…

Controlled Antibiotics Release System through Simple Blended Electrospun Fibers for Sustained Antibacterial Effects.

PubMed

Zhang, Zixin; Tang, Jianxiong; Wang, Heran; Xia, Qinghua; Xu, Shanshan; Han, Charles C

2015-12-09

Implantation of sustained antibacterial system after abdominal surgery could effectively prevent complicated intra-abdominal infection. In this study, a simple blended electrospun membrane made of poly(D,L-lactic-co-glycolide) (PLGA)/poly(dioxanone) (PDO)/Ciprofloxacin hydrochloride (CiH) could easily result in approximately linear drug release profile and sustained antibacterial activity against both Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The addition of PDO changed the stack structure of PLGA, which in turn influenced the fiber swelling and created drug diffusion channels. It could be a good candidate for reducing postoperative infection or be associated with other implant to resist biofilm formation.

The impact of newly produced protein and dietary fiber rich fractions of yellow pea (Pisum sativum L.) on the structure and mechanical properties of pasta-like sheets.

PubMed

Muneer, Faraz; Johansson, Eva; Hedenqvist, Mikael S; Plivelic, Tomás S; Markedal, Keld Ejdrup; Petersen, Iben Lykke; Sørensen, Jens Christian; Kuktaite, Ramune

2018-04-01

Two fractions from pea (Pisum sativum L.), protein isolate (PPI) and dietary fiber (PF), were newly produced by extraction-fractionation method and characterized in terms of particle size distribution and structural morphology using SEM. The newly produced PPI and PF fractions were processed into pasta-like sheets with varying protein to fiber ratios (100/0, 90/10, 80/20, 70/30 and 50/50, respectively) using high temperature compression molding. We studied protein polymerization, molecular structure and protein-fiber interactions, as well as mechanical performance and cooking characteristics of processed PPI-PF blends. Bi-modal particle size distribution and chemical composition of the PPI and PF fractions influenced significantly the physicochemical properties of the pasta-like sheets. Polymerization was most pronounced for the 100 PPI, 90/10 and 80/20 PPI-PF samples as studied by SE-HPLC, and polymerization decreased with addition of the PF fraction. The mechanical properties, as strength and extensibility, were likewise the highest for the 100 PPI and 90/10 PPI-PF blends, while the E-modulus was similar for all the studied blends (around 38 MPa). The extensibility decreased with the increasing amount of PF in the blend. The highest amounts of β-sheets were found in the pasta-like sheets with high amounts of PPI (100, 90 and 80%), by FT-IR. An increase in PF fraction in the blend, resulted into the high amounts of unordered structures as observed by FT-IR, as well as in an increase in the molecular scattering distances observed by SAXS. The water uptake increased and cooking loss decreased with increased proportions of the PF fraction, and the consistency of 10 min cooked pasta-like sheets were alike al dente texture. The new knowledge obtained in this study on the use of extraction-fractionation method to produce novel PPI and PF fractions for developing innovative high nutritious food can be of a great importance. The obtained knowledge on the pea protein and fiber processing behaviour could greatly contribute to a better control of functional properties of various temperature-processed products from yellow pea. Copyright © 2018 Elsevier Ltd. All rights reserved.

The effect of thiolated additives on the properties of wheat gluten based plastics, aqueous solutions and electrospun fibers

NASA Astrophysics Data System (ADS)

Dong, Jing

Wheat gluten (WG) is a promising substitute for petroleum-based plastics due to its unique ability to form a cohesive blend with viscoelastic properties once plasticized. Previous work blending WG with thiolated poly(vinyl alcohol) (TPVA) showed that both the strength and elongation of compression molded native WG bars can be improved via thiol/disulfide interchange reactions between WG and TPVA. In this study, the morphology of WG/TPVA blends was investigated by atomic force (AFM) and transmission electron microscopy (TEM), as well as by modulated dynamic scanning calorimetry (MDSC). Consistent with our earlier results, AFM and TEM imaging clearly indicated that TPVA is much more compatible with WG compared with poly(vinyl alcohol) (PVA) although there are still two phases in the blend: one WG rich phase and another TPVA rich phase. TPVA was also blended with WG in an aqueous solvent (1/1 (v/v) water/1-propanol mixture) to improve its solubility and spinnability. Control experiments were conducted with PVA and dithiothreitol (DTT) for comparison purposes. The concentration and the thiolation level of TPVA were also varied to explore the parameter space. The interactions of thiol groups from TPVA and soluble WG were found to be important during electrospinning. The fiber diameter became more uniform and the fiber quality increased very noticeably when TPVA was included. Furthermore, the time-dependent rheology behaviors of TPVA/WG and DTT/WG electrospinning solutions were investigated by using steady shear sweeps, oscillatory frequency sweeps, SE-HPLC and free -SH content determination. A two-step mechanism of interaction was proposed for DTT/WG and TPVA/WG solutions based on current results and other earlier studies. In comparison with WG and PVA/WG solutions, the reduction and reformation of disulfide linkages in both TPVA/WG and DTT/WG solutions were believed to play a key role in determining the rheological properties and molecular weight distribution of WG fractions in the solution. Finally, the effect of thiol groups on the electrospinning behavior of pure TPVA aqueous solution was studied. It has found that the fiber quality was improved obviously within the first few days of solution preparation, while no fiber can be obtained when the viscosity became too high.

Processing and characterization of solid and microcellular PHBV/PBAT blend and its RWF/nanoclay composites

Treesearch

Alireza Javadi; Yottha Srithep; Jungjoo Lee; Srikanth Pilla; Craig Clemons; Shaoqin Gong; Lih-Sheng Turng

2010-01-01

Solid and microcellular components made of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/ poly (butylenes adipate-co-terephthalate) (PBAT) blend (weight ration of PHBV:PBAT = 30:70), recycled wood fiber (RWF), and nanoclay (NC) were prepared via a conventional and microcellular-injection molding process, respectively. Morphology, thermal properties, and...

Controlled and high throughput fabrication of poly(trimethylene terephthalate) nanofibers via melt extrusion of immiscible blends

USDA-ARS?s Scientific Manuscript database

Immiscible blends of cellulose acetate butyrate (CAB) and poly(trimethylene terephthalate) (PTT) were melt extruded through a two strand rod die. The extrudates were hot-drawn at the die exit at different draw ratios. PTT fibers were obtained by removal of the CAB matrix from the drawn extrudates, a...

Controlled and high throughput fabrication of poly(trimethylene terphthalate) nanofibers via melt extrusion of immiscible blends

USDA-ARS?s Scientific Manuscript database

Immiscible blends of cellulose acetate butyrate (CAB) and poly(trimethylene terephthalate) (PTT) were melt extruded through a two strand rod die. The extrudates were hot-drawn at the die exit at different draw ratios. PTT fibers were obtained by removal of the CAB matrix from the drawn extrudates, a...

Fiber-based architectures for organic photovoltaics

NASA Astrophysics Data System (ADS)

Liu, Jiwen; Namboothiry, Manoj A. G.; Carroll, David L.

2007-02-01

Using poly(3-hexylthiophene) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 bulk-heterojunction blends as the absorbing material, organic photovoltaic devices have been fabricated onto multimode optical fibers. The behavior of the short circuit current density, filling factor, and open circuit voltage as the angle of the incident light onto the cleaved fiber face is varied suggests that the evanescent field at the interface between the fiber and the transparent contact may play a role in coupling light from the fiber into the device. Further, optical loss into the device increases as the fiber diameter decreases.

Antioxidant activity of rye bread enriched with milled buckwheat groats fractions.

PubMed

Żmijewski, Mirosław; Sokół-Łętowska, Anna; Pejcz, Ewa; Orzeł, Dagmara

2015-01-01

Buckwheat, despite its broad nutritional benefits, is still not widely appreciated grain. It contains a protein with preferred amino acid composition and it is a valuable source of micronutrients and vitamins of the B group and vitamin E. Moreover, buckwheat groats have a high amount of polyphenols, including flavonoids and flavones. Eating rye bread is beneficial due to its high content of dietary fiber, phenolic acids and characteristic taste and aroma. Therefore, the use of rye flour and buckwheat mill products for bread may allow obtaining a product of high nutritional value and flavor. The aim of the study was to evaluate the influence of buckwheat products addition and baking process on the antioxidant properties of rye-buckwheat blends and breads. Experimental material was rye flour type 580 and buckwheat flour, wholegrain flour and bran obtained by grinding buckwheat groats. Buckwheat products share was 20 and 35%. The control was the rye flour. In the rye-buckwheat blends and bread loaves, the contents of selected flavonoids by HPLC method, total polyphenols content by Folin-Ciocalteu method and the antioxidant activity by the DPPH˙ radical scavenging method were determined. Buckwheat bran was significantly richer in total polyphenols, rutin, quercetin, orientin and isoorientin than other buckwheat products and rye flour. Bread after baking contained similar amount of total polyphenols and quercetin and have a comparable ability to scavenge 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH˙) than the corresponding blends. Baking process negatively affected the amount of rutin, orientin and isoorientin. The use of buckwheat bran as a replacement for wheat flour in bread significantly increases its nutritional value. The process of baking unequally affects the content of particular groups of antioxidant compounds.

Method of forming composite fiber blends

NASA Technical Reports Server (NTRS)

McMahon, Paul E. (Inventor); Chung, Tai-Shung (Inventor); Ying, Lincoln (Inventor)

1989-01-01

The instant invention involves a process used in preparing fibrous tows which may be formed into polymeric plastic composites. The process involves the steps of (a) forming a tow of strong filamentary materials; (b) forming a thermoplastic polymeric fiber; (c) intermixing the two tows; and (d) withdrawing the intermixed tow for further use.

Electrokinetic and hemostatic profiles of nonwoven cellulosic/ synthetic fiber blends with unbleached cotton

USDA-ARS?s Scientific Manuscript database

Greige cotton contains waxes and pectin on the outer surface of the fiber that are removed from bleached cotton, but present added potential for wound dressing functionality. Innovations to mechanically clean and sterilize greige cotton (or non-bleached cotton) do not remove these exterior componen...

Whiteness and absorbency of hydroentangled cotton-based nonwoven fabrics of different constituent fibers and fiber blends

USDA-ARS?s Scientific Manuscript database

This manuscript reports result of the research efforts devoted to the exploration and development of greige (non-bleached) cotton-containing nonwoven fabrics that likely could be made optimally competitive in cost, quality and performance to existing products that presently and predominantly use man...

Short communication: Using diurnal patterns of (13)C enrichment of CO2 to evaluate the effects of nitrate and docosahexaenoic acid on fiber degradation in the rumen of lactating dairy cows.

PubMed

Klop, G; Bannink, A; Dieho, K; Gerrits, W J J; Dijkstra, J

2016-09-01

Nitrate decreases enteric CH4 production in ruminants, but may also negatively affect fiber degradation. In this experiment, 28 lactating Holstein dairy cows were grouped into 7 blocks. Within blocks, cows were randomly assigned to 1 of 4 isonitrogenous treatments in a 2×2 factorial arrangement: control (CON); NO3 [21g of nitrate/kg of dry matter (DM)]; DHA [3g of docosahexaenoic acid (DHA)/kg of DM]; or NO3+DHA (21g of nitrate/kg of DM and 3g of DHA/kg of DM). Cows were fed a total mixed ration consisting of 21% grass silage, 49% corn silage, and 30% concentrates on a DM basis. Based on the difference in natural (13)C enrichment and neutral detergent fiber and starch content between grass silage and corn silage, we investigated whether a negative effect on rumen fiber degradation could be detected by evaluating diurnal patterns of (13)C enrichment of exhaled carbon dioxide. A significant nitrate × DHA interaction was found for neutral detergent fiber digestibility, which was reduced on the NO3 treatment to an average of 55%, as compared with 61, 64, and 65% on treatments CON, DHA, and NO3+DHA, respectively. Feeding nitrate, but not DHA, resulted in a pronounced increase in (13)C enrichment of CO2 in the first 3 to 4 h after feeding only. Results support the hypothesis that effects of a feed additive on the rate of fiber degradation in the rumen can be detected by evaluating diurnal patterns of (13)C enrichment of CO2. To be able to detect this, the main ration components have to differ considerably in fiber and nonfiber carbohydrate content as well as in natural (13)C enrichment. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Modelling Blended Solutions for Higher Education: Teaching, Learning, and Assessment in the Network and Mobile Technology Era

ERIC Educational Resources Information Center

Bocconi, Stefania; Trentin, Guglielmo

2014-01-01

The article addresses the role of network and mobile technologies in enhancing blended solutions with a view to (a) enriching the teaching/learning processes, (b) exploiting the opportunities it offers for their observability, and hence for their monitoring and formative/summative assessment. It will also discuss how such potential can only be…

Effects of barley β-glucan-enriched flour fractions on the glycaemic index of bread.

PubMed

Finocchiaro, Franca; Ferrari, Barbara; Gianinetti, Alberto; Scazzina, Francesca; Pellegrini, Nicoletta; Caramanico, Rosita; Salati, Claudia; Shirvanian, Vigen; Stanca, Antonio Michele

2012-02-01

The aim of this research was to evaluate β-glucan-enriched flours, obtained from barleys with either normal or waxy starch, for their effects on the glycaemic index (GI) and the quality of bread. Rheological results confirmed that when barley flour was included in the dough the overall quality of bread slightly worsened. However, positive consequences on glycaemia were obtained with the normal starch barley: the GI of all-wheat bread (82.8 ± 7.2) was significantly reduced (57.2 ± 7.9) when 40% of wheat flour was substituted with β-glucan-enriched barley flour (6.0% ± 0.1 β-glucan in the final flour blend). In contrast, this positive effect was significantly reduced (GI: 70.1 ± 9.1) when 40% of wheat flour was substituted with the β-glucan-enriched flour of a waxy barley (CDC Alamo; 6.6 ± 0.2 β-glucan in the final flour blend), suggesting that the ability of β-glucans to lower the GI was affected by the barley starch-type.

Processable Aromatic Polyimide Thermoplastic Blends

NASA Technical Reports Server (NTRS)

Baucom, Robert M; Johnston, Norman J.; St. Clair, Terry L.; Nelson, James B.; Gleason, John R.; Proctor, K. Mason

1988-01-01

Method developed for preparing readily-processable thermoplastic polyimides by blending linear, high-molecular-weight, polyimic acid solutions in ether solvents with ultrafine, semicrystalline, thermoplastic polyimide powders. Slurries formed used to make prepregs. Consolidation of prepregs into finsihed composites characterized by excellent melt flow during processing. Applied to film, fiber, fabric, metal, polymer, or composite surfaces. Used to make various stable slurries from which prepregs prepared.

Release of tetracycline hydrochloride from electrospun poly(ethylene-co-vinylacetate), poly(lactic acid), and a blend.

PubMed

Kenawy, El-Refaie; Bowlin, Gary L; Mansfield, Kevin; Layman, John; Simpson, David G; Sanders, Elliot H; Wnek, Gary E

2002-05-17

Electrospun fiber mats are explored as drug delivery vehicles using tetracycline hydrochloride as a model drug. The mats were made either from poly(lactic acid) (PLA), poly(ethylene-co-vinyl acetate) (PEVA), or from a 50:50 blend of the two. The fibers were electrospun from chloroform solutions containing a small amount of methanol to solubilize the drug. The release of the tetracycline hydrochloride from these new drug delivery systems was followed by UV-VIS spectroscopy. Release profiles from the electrospun mats were compared to a commercially available drug delivery system, Actisite (Alza Corporation, Palo Alto, CA), as well as to cast films of the various formulations.

Preparation and properties of banana fiber-reinforced composites based on high density polyethylene (HDPE)/Nylon-6 blends.

PubMed

Liu, H; Wu, Q; Zhang, Q

2009-12-01

Banana fiber (BaF)-filled composites based on high density polyethylene (HDPE)/Nylon-6 blends were prepared via a two-step extrusion method. Maleic anhydride grafted styrene/ethylene-butylene/styrene triblock polymer (SEBS-g-MA) and maleic anhydride grafted polyethylene (PE-g-MA) were used to enhance impact performance and interfacial bonding between BaF and the resins. Mechanical, crystallization/melting, thermal stability, water absorption, and morphological properties of the composites were investigated. In the presence of SEBS-g-MA, better strengths and moduli were found for HDPE/Nylon-6 based composites compared with corresponding HDPE based composites. At a fixed weight ratio of PE-g-MA to BaF, an increase of BaF loading up to 48.2 wt.% led to a continuous improvement in moduli and flexural strength of final composites, while impact toughness was lowered gradually. Predicted tensile modulus by the Hones-Paul model for three-dimensional random fiber orientation agreed well with experimental data at the BaF loading of 29.3 wt.%. However, the randomly-oriented fiber models underestimated experimental data at higher fiber levels. It was found that the presence of SEBS-g-MA had a positive influence on reinforcing effect of the Nylon-6 component in the composites. Thermal analysis results showed that fractionated crystallization of the Nylon-6 component in the composites was induced by the addition of both SEBS-g-MA and PE-g-MA. Thermal stability of both composite systems differed slightly, except an additional decomposition peak related to the minor Nylon-6 for the composites from the HDPE/Nylon-6 blends. In the presence of SEBS-g-MA, the addition of Nylon-6 and increased BaF loading level led to an increase in the water absorption value of the composites.

Method of forming composite fiber blends and molding same

NASA Technical Reports Server (NTRS)

McMahon, Paul E. (Inventor); Chung, Tai-Shung (Inventor)

1989-01-01

The instant invention involves a process used in preparing fibrous tows which may be formed into polymeric plastic composites. The process involves the steps of (a) forming a tow of strong filamentary materials; (b) forming a thermoplastic polymeric fiber; (c) intermixing the two tows; and (d) withdrawing the intermixed tow for further use.

Electrospinning of Polyaniline/Poly(Lactic Acid) Ultrathin Fibers: Process and Statistical Modeling using a Non-Gaussian Approach

USDA-ARS?s Scientific Manuscript database

Fibers of poly(lactic acid) (PLA) blended with p-toluenesulfonic acid-doped polyaniline, PAni.TSA, were obtained by lectrospinning, following a factorial design which was used mainly to study the effect of four process parameters (PLA solution concentration, PAni solution concentration, applied volt...

Effect of thermoplastic polyurethane (TPU) on the thermal and mechanical properties of polylactic acid (PLA)/curcumin blends

NASA Astrophysics Data System (ADS)

Sharifah, I. S. S.; Adnan, M. D. A.; Nor Khairusshima, M. K.; Shaffiar, N. M.; Buys, Y. F.

2018-01-01

Polylactic acid (PLA) is known to be brittle by nature and thus limits the flexibility of the polymer. A possible solution to enhance the flexibility of PLA is to add a flexible polymeric based material such as thermoplastic polyurethane (TPU). In this study, 30-50 wt% of TPU was added into PLA/curcumin blends to improve its flexibility. Thermal analysis using differential scanning calorimetry shows that further additions of TPU at the expense of PLA did not affect the glass transition temperature, crystallisation temperature and melting temperature of the blends. Fibers of PLA/curcumin/TPU were successfully drawn and Single Fiber Tensile Test (SFTT) showed vast improvement in elongation at break. The initial addition of 30 wt% of TPU to the brittle PLA/curcumin composition causes a significant increase in elongation at break by 39 times and further additions at 50 wt %, the elongation at break increases by 105 times. However, with the increase in elongation, a decrease in strength and Young’s modulus was observed.

Characterization of cassava starch based foam blended with plant proteins, kraft fiber, and palm oil.

PubMed

Kaisangsri, Nattapon; Kerdchoechuen, Orapin; Laohakunjit, Natta

2014-09-22

Cassava starch foam (CSF) trays blended with zein, gluten, soy protein, kraft fiber, and palm oil at various concentrations: 0, 5, 10 and 15% by weight of starch, were characterized. The addition of zein and gluten into CSF resulted in consolidated and homogeneous structural foams compared to its controls. Moreover, the flexural and compressive strength increased with increasing kraft, zein and gluten. CSF containing 15% kraft gave the highest flexural and compressive strength. However, the addition of palm oil into CSF gave the lowest flexural strength and compressive strength. The observed water absorption and water solubility index of CSFs blended with 15% zein and 15% gluten protein was lowest. Although kraft, zein and gluten could improve mechanical properties, water absorption and water solubility were greater than the expanded polystyrene foam (EPS). The CSF trays in this study might be an alternative for packing low water content foods. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of a room-temperature ionic liquid on the structure and properties of electrospun poly(vinylidene fluoride) nanofibers.

PubMed

Xing, Chenyang; Guan, Jipeng; Li, Yongjin; Li, Jingye

2014-03-26

Novel anti-static nanofibers based on blends of poly(vinylidene fluoride) (PVDF) and a room-temperature ionic liquid (RTIL), 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6], were fabricated using an electrospinning approach. The effects of the RTIL on the morphology, crystal structure, and physical properties of the PVDF nanofibers were investigated. Incorporation of RTIL leads to an increase in the mean fiber diameter and the rough fiber surface of the PVDF/RTIL composite nanofibers compared with the neat PVDF nanofibers. The PVDF in the PVDF/RTIL nanofibers exhibits an extremely high content (almost 100%) of β crystals, in contrast to the dominance of PVDF γ crystals in bulk melt-blended PVDF/RTIL blends. Nonwoven fabrics produced from the electrospun PVDF/RTIL composite nanofibers show better stretchability and higher electrical conductivity than those made from neat PVDF without RTIL, and are thus excellent antielectrostatic fibrous materials. In addition, RTIL greatly improved the hydrophobicity of the PVDF fibers, enabling them to effectively separate a mixture of tetrachloromethane (CCl4) and water. The extremely high β content, excellent antielectrostatic properties, better stretchability, and hydrophobicity of the present PVDF/RTIL nanofibers make them a promising candidate for micro- and nanoscale electronic device applications.

The Best of Both Worlds: Blending History and Geography in the K-12 Curriculum.

ERIC Educational Resources Information Center

Boehm, Richard G.; Saxe, David Warren; Rutherford, David J.

This report shows how the study of U.S. history can be enriched by blending geography into the curriculum. Because the fields of history and geography have not been melded together in terms of curricula, often history is not taught in relation to geography and geography has tended to be taught primarily as location/place information. The report…

Pilot Line Development of High-Performance Thermal Insulation

DTIC Science & Technology

1989-09-01

with the fiber blend described, full attention was given to the problems of pilot pro- duction. C. Assembly of the Pilot Production Line and Initial...that virtually all possible static control steps had been taken, we presented the problem to the fiber manufacturer, TeiJin. They re- sponded by...1988. The line was operated continuously during production of the 5-roll sample se, as static generation within the fiber was no longer a problem

Chemical composition, rheological, quality characteristics and storage stability of buns enriched with coriander and curry leaves.

PubMed

Sudha, M L; Rajeswari, G; Venkateswara Rao, G

2014-12-01

Effect of addition of normal (NL) and dehydrated (DL) curry leaves (Murraya koeniggi) and coriander leaves (Corinadrum sativum) in the ratio of 1:1 to refined wheat flour (WF) or a blend of refined wheat flour-whole wheat flour (WF-WWF, 1:1) on the rheological, nutritional, storage and quality characteristics of the buns were studied. Water absorption increased on addition of increasing levels of DL from 0 to 7.5 % to WF-WWF when compared to WF. Dough weakening was greater when DL was added to WF-WWF as seen in decrease in dough stability and abscissa at rupture values. Addition of gluten and emulsifiers improved the quality characteristics of buns prepared using either 25 % NL or 5 % DL. Storage stability of buns with DL was better. The protein, dietary fiber, iron and carotenoids in buns prepared from WF-WWF were higher. The results indicate the utilization of leaves in dehydrated form in the preparation of nutritionally improved buns.

High-Fiber Orange Juice as a Nutrition Supplement in Women: A Randomized, Double-Blind, Placebo-Controlled Study of Tolerance and Effectiveness.

PubMed

Bergamasco, Christiane; Horie, Lilian Mika; Torrinhas, Raquel Susana; Waitzberg, Dan L

2015-11-01

The daily consumption of dietary fiber is frequently below suggested recommendations. Using a double-blind, controlled, randomized study, we assessed the efficiency and tolerance of a fiber-enriched orange juice to supplement fiber intake in women. After 1 week of noninterventional observation, 192 healthy adult women ingested 400 mL of orange juice for 21 days, which either was not (placebo group) or was enriched with fiber (fiber group). Orange juice ingestion was registered daily and controlled for each week during the study period. Macronutrient, fiber, and energy intake were determined using a 3-day food record, validated food chemical composition databases, and the "Pro Diet" software. Gastrointestinal symptoms were self-evaluated daily by scoring 4 grades of symptom intensity and using a visual analog scale to grade pain severity. No changes were observed for macronutrient and energy ingestion. For the placebo group (n = 97), the total fiber intake record was under the daily recommended value. In contrast, the fiber group (n = 95) displayed higher comparative values of total and soluble fiber consumption (P ≤ .001), achieving the daily recommended values of fiber intake. Both groups reported an increased frequency of slight bloating and rumbles over time (P ≤ .05). The fiber group also experienced a higher frequency of slight flatulence over time (P = .002). Consumption of fiber-enriched orange juice was efficient to achieve the daily fiber intake recommendation for women, was not accompanied by intense adverse events, and may represent a suitable method to supplement fiber intake in woman. © 2014 American Society for Parenteral and Enteral Nutrition.

Loading blended, low-enriched uranium fuel in browns ferry units 2 and 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, C.; Eichenberg, T.; Haun, J.

2006-07-01

This paper summarizes fuel and cycle design results for the Tennessee Valley Authority (TVA) / Dept. of Energy (DOE) program to burn blended, low-enriched uranium (BLEU) material in the Browns Ferry Nuclear Units 2 and 3. The BLEU material typically has about 60 times the allowed limit of U-236 in what would be defined as commercial, i.e., virgin, uranium. U-236 in particular is a strong neutron absorber. Also included is a comparison of cycles using commercial uranium versus BLEU to determine the impact on key core design parameters of the high U-236 content in the BLEU. Finally, there is amore » short discussion of the economic advantages of BLEU fuel. (authors)« less

Using Dynamic Mechanical Spectroscopy to Monitor the Crystallization of PP/MAPP Blends in the Presence of Wood

Treesearch

Michael P. Wolcott; Suzhou Yin; Timothy G. Rials

2000-01-01

Crystal morphology of thermoplastics is known to be strongly influenced by the presence of solid suhstrntes like fibers or fillers. For wood, this interphase development is govemed by the chemical composition of the thermoplastic and substrate. The crystallization of PP/MAPP blends WBS observed using polarized light microscopy and quantified using DSC and DM.4....

Effect of a rice bran fiber diet on serum glucose levels of diabetic patients in Brazil.

PubMed

Rodrigues Silva, Cecilia; Dutra de Oliveira, José Eduardo; de Souza, Rui Augusto Hudari Gonçalves; Silva, Hugo Candido

2005-03-01

Eleven diabetic patients: 5, type 1 and 6, type 2 received a low-fiber diet (I) during 1 week and during the next 7 days the same diet, enriched with 40 g of fiber (30.6% insoluble and 11.7% soluble components) from rice bran (II) per day. Results showed that mean fasting and postprandial serum glucose levels were reduced, but values of high fiber diet were significantly lower (p < 0.001) than that of the lower fiber diet. For all patients, the high-fiber diet increased fecal weight. This increase was due to the fiber excreted, rather than water retained. There was no relationship between the increase in fiber intake and its fecal excretion. Sucrose and raffinose were found in the bran, but not in the feces. Lactose was present in the stools of the patients receiving enriched diet.

Electrospinning-based synthesis of highly ordered mesoporous silica fiber for lab-in-syringe enrichment of plasma peptides.

PubMed

Zhu, Gang-Tian; Li, Xiao-Shui; Fu, Xiao-Meng; Wu, Jian-Yuan; Yuan, Bi-Feng; Feng, Yu-Qi

2012-10-14

Silica fiber with highly ordered mesoporous structure and continuously long fibrous property was synthesized on a large-scale for the first time. It can be applied to the rapid (less than 3 min) and effective enrichment of endogenous peptides with a novel lab-in-syringe approach.

The influence of chemical surface modification of kenaf fiber using hydrogen peroxide on the mechanical properties of biodegradable kenaf fiber/poly(lactic acid) composites.

PubMed

Razak, Nur Inani Abdul; Ibrahim, Nor Azowa; Zainuddin, Norhazlin; Rayung, Marwah; Saad, Wan Zuhainis

2014-03-07

Bleaching treatment of kenaf fiber was performed in alkaline medium containing hydrogen peroxide solution maintained at pH 11 and 80 °C for 60 min. The bleached kenaf fiber was analyzed using Fourier Transform Infrared (FTIR) and X-ray Diffraction (XRD) analysis. The bleached kenaf fiber was then compounded with poly-(lactic acid) (PLA) via a melt blending method. The mechanical (tensile, flexural and impact) performance of the product was tested. The fiber treatment improved the mechanical properties of PLA/bleached kenaf fiber composites. Scanning electron micrograph (SEM) morphological analysis showed improvement of the interfacial adhesion between the fiber surface and polymer matrix.

Leaf spring made of fiber-reinforced resin

NASA Technical Reports Server (NTRS)

Hori, J.

1986-01-01

A leaf spring made of a matrix reinforced by at least two types of reinforcing fibers with different Young's modulus is described in this Japanese patent. At least two layers of reinforcing fibers are formed by partially arranging the reinforcing fibers toward the direction of the thickness of the leaf spring. A mixture of different types of reinforced fibers is used at the area of boundary between the two layers of reinforced fibers. The ratio of blending of each type of reinforced fiber is frequently changed to eliminate the parts where discontinuous stress may be applied to the leaf spring. The objective of this invention is to prevent the rapid change in Young's modulus at the boundary area between each layer of reinforced fibers in the leaf spring.

Engineering Enriched Microenvironments with Gradients of Platelet Lysate in Hydrogel Fibers.

PubMed

Santo, Vítor E; Babo, Pedro; Amador, Miguel; Correia, Cláudia; Cunha, Bárbara; Coutinho, Daniela F; Neves, Nuno M; Mano, João F; Reis, Rui L; Gomes, Manuela E

2016-06-13

Gradients of physical and chemical cues are characteristic of specific tissue microenvironments and contribute toward morphogenesis and tissue regeneration upon injury. Recent advances on microfluidics and hydrogel manipulation raised the possibility of generating biomimetic biomaterials enriched with bioactive factors and encapsulating cells following designs specifically tailored for a target application. The novelty of this work relies on the combination of methacrylated gellan gum (MeGG) with platelet lysate (PL), aiming to generate novel advanced 3D PL-enriched photo-cross-linkable hydrogels and overcoming the lack of adhesion sites provided by the native MeGG hydrogels. This combination takes advantage of the availability, enriched growth factor composition, and potential autologous application of PL while simultaneously preserving the ability provided by MeGG to tailor mechanical properties, protein release kinetics, and shape of the construct according to the desired goal. Incorporation of PL in the hydrogels significantly improved cellular adhesion and viability in the constructs. The use of microfluidic tools allowed the design of a fiber-like hydrogel incorporating a gradient of PL along the length of the fiber. These spatial protein gradients led to the viability and cell number gradients caused by maintenance of human umbilical vein endothelial cells (HUVECs) survival in the fibers toward the PL-enriched sections in comparison with the nonloaded MeGG sections of the fibers. Altogether, we propose a proof of concept strategy to design a PL gradient biomaterial with potential in tissue engineering approaches and analysis of cell-microenvironment interactions.

Functional Biomaterials: Solution Electrospinning and Gelation of Whey Protein and Pullulan

NASA Astrophysics Data System (ADS)

Sullivan, Stephanie Tolstedt

Utilizing biomaterials that are biodegradable, biocompatible and edible serve well for food products as well as biomedical applications. Biomaterials whey protein and pullulan both have these characteristics. Whey proteins (WP) have been used in food products for many years and more recently in pharmaceutical products. They have the ability to form both gels and stable foams. Pullulan (PULL) has also been used in both food and pharmaceutical products, and is a highly water soluble, non-gelling polysaccharide and has been used primarily as a film former. Herein, we investigate the ability of whey protein and pullulan to form nanofibers and gels. Combining their distinct properties allows the ability to uniquely manipulate nanofiber and gel characteristics and behavior for a variety of applications, from food to even tissue scaffolding. First, we determined the electrospinnability of aqueous whey protein solutions. Both whey protein isolate (WPI) and one of its major components beta--lactoglobulin (BLG), either in native or denatured form, yielded interesting micro and nanostructures when electrosprayed; while nanofiber production required blending with a spinnable polymer, poly(ethylene oxide) (PEO). WP:PEO solutions were also successfully electrospun at acidic pH (2≤pH≤3), which could improve shelf life. Fourier Transform Infrared Reflectance (FTIR) analysis of WP:PEO fiber mat indicated some variation in WP secondary structure with varying WPI concentration (as WPI increased, % alpha-helix increased and beta-turn decreased) and pH (as pH decreased from neutral (7.5) to acidic (2), % beta-sheet decreased and alpha-helix increased). X-ray Photoelectron Spectroscopy (XPS) also confirmed the presence of WP on the surface of the blend fibers, augmenting the FTIR analysis. Interestingly, WP:PEO composite nanofibers maintained its fibrous morphology at temperatures as high as 100 °C, above the 60 °C PEO melting point. Further, we show that the blend mats retained a fibrous structure after the heat treatment. Our second goal was to evaluate the ability of aqueous blends of whey protein and pullulan to form gels. We first looked at WP-PULL blend solutions at room temperature, finding an increasing linear trend in low shear viscosity as the relative concentration of pullulan increased. Blend solution samples were then heated to determine the ability of the blend solutions to form a gelled network. Starting with a homogeneous WP gel, adding PULL, at native mix or alkaline pH, maintained a transparent homogeneous microstructure, but resulted in weaker gels based on its response to stress. At WP isoelectric point (IEP) pH, both protein and blend gels became opaque due to protein aggregation, forming a particulate gel. All gels at the IEP were weaker, yielding at much lower stress and corresponding strain, due to the protein aggregation. The addition of transglutaminase enzyme yielded a stronger network than the native samples, while the addition of sodium trimetaphosphate salt yielded weaker gels and also induced relevant particle and/or course stranded microstructure in both pH 8 and IEP cases. The third part of this study demonstrated the ability of pullulan to form nanofibers in the solution electrospinning process. Aqueous pullulan solutions were able to form defect-free nanofibers with a minimum concentration of 15 w/w%. Pullulan and PULL:hydroxypropyl-beta- cyclodextrin (HPBCD) blend fibers were chemically crosslinked to form insoluble fibers using ethylene glycol diglycidyl ether (EGDGE), a chemical used in food contact coating applications. Next, solution blends of pullulan with whey protein were prepared and also electrospun at varying pH and relative biomaterial concentrations at 17 total w/w%. PULL-WP blend nanofiber mats were crosslinked via heat treatment and found to be both swellable and insoluble. When dried, the mats did not return to their original fiber state and instead appear to be gelatinous fibers in nature after soaking, and thereby making them potentially useful for tissue scaffolding applications. A fourth accomplishment was to utilize Near Infrared Reflectance (NIR) Spectroscopy and Chemometrics techniques to analyze commercial whey protein powder characteristics such as protein, fat and moisture content as well as pH. NIR has been utilized in the food and pharmaceutical industries for quality control as a valuable compliment to or replacement for more expensive testing such as High Performance Liquid Chromatography. Analysis resulted in the development of quantitative, linear regression models to correlate whey protein powder characteristics to NIR data. Whey protein's ability to form gels and pullulan's electrospinnability to form nanofibers is combined herein to form blends of both that can be changed with varying concentration, pH, temperature and supplementation with food-safe additives. The study correlates mechanical properties and microstructure of blend gels and nanofibers and provides a foundation for further study of swellable network for tissue application specifically in the use of pullulan-whey protein heat treated nanofiber mats.

Production of silk sericin/silk fibroin blend nanofibers

NASA Astrophysics Data System (ADS)

Zhang, Xianhua; Tsukada, Masuhiro; Morikawa, Hideaki; Aojima, Kazuki; Zhang, Guangyu; Miura, Mikihiko

2011-08-01

Silk sericin (SS)/silk fibroin (SF) blend nanofibers have been produced by electrospinning in a binary SS/SF trifluoroacetic acid (TFA) solution system, which was prepared by mixing 20 wt.% SS TFA solution and 10 wt.% SF TFA solution to give different compositions. The diameters of the SS/SF nanofibers ranged from 33 to 837 nm, and they showed a round cross section. The surface of the SS/SF nanofibers was smooth, and the fibers possessed a bead-free structure. The average diameters of the SS/SF (75/25, 50/50, and 25/75) blend nanofibers were much thicker than that of SS and SF nanofibers. The SS/SF (100/0, 75/25, and 50/50) blend nanofibers were easily dissolved in water, while the SS/SF (25/75 and 0/100) blend nanofibers could not be completely dissolved in water. The SS/SF blend nanofibers could not be completely dissolved in methanol. The SS/SF blend nanofibers were characterized by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry, and differential thermal analysis. FTIR showed that the SS/SF blend nanofibers possessed a random coil conformation and ß-sheet structure.

Using aligned poly(3-hexylthiophene)/poly(methyl methacrylate) blend fibers to detect volatile organic compounds

NASA Astrophysics Data System (ADS)

Chan, Shun-Hsiang; Lin, Tz-Feng; Wu, Ming-Chung; Chen, Shih-Hsuan; Su, Wei-Fang; Lai, Chao-Sung

2018-04-01

In this study, we developed a novel sensing material fabricated using a poly(3-hexylthiophene) (P3HT)/poly(methyl methacrylate) (PMMA) blend fiber on a glass substrate. The sensing materials can easily be used for sensing toluene vapor detected from extinction spectral changes. The extinction spectra variation is noted from the absorption of volatile organic compounds in a highly specific surface area of fibrous coating. An electrospinning technique is applied to generate a nonwoven structure and uniaxial orientation by fibrous coating. The response of the uniaxially orientated fibrous film is even improved at several toluene vapor concentrations. The best detection limit of this well-aligned fibrous film is up to 200 ppm for toluene vapor.

Injection molded composites from kenaf and recycled plastic

Treesearch

Poo Chow; Dilpreet S. Bajwa; Wen-da Lu; John A. Youngquist; Nicole M. Stark; Qiang Li; Brent English

1998-01-01

Kenaf-based thermoplastic composites were developed and evaluated in this study. The kenaf stems were collected from farms in central Illinois. The kenaf fibers were blended with commercial virgin plastic or polypropylene and with recycled plastics or low-cost polyethylene in form of post-consumer film wastes and shrink wraps. Investigations on the fiber properties and...

Opportunities for composites from recycled wastewood-based resources: A problem analysis and research plan

Treesearch

Roger M. Rowell; Henry Spelter; Rodger A. Arola; Phil Davis; Tom Friberg; Richard W. Hemingway; Tim Rials; David Luneke; Ramani Narayan; John Simonsen; Don White

1993-01-01

There are many opportunities to produce composites from recycled biobased fiber. The fiber can be used alone to make low-cost and high-performance composites, combined with inorganic materials, or combined with other recycled materials, such as plastics, to produce mixtures, compatibilized blends, and alloys. This report describes the resources available: problems...

Effects of corn fiber gum (CFG) on the pasting and thermal behaviors of maize starch

USDA-ARS?s Scientific Manuscript database

Corn fiber gum (CFG) is a novel arabinoxylan hydrocolloid. Recent research showed its considerable potential in food processing. In this study, the interactions of maize starch and CFG were studied. Maize starch/CFG blend gels were prepared from maize starch suspension mixed with 0.1%, 0.25%, 0.5%, ...

Evaluation of forest thinning materials for TMP production

Treesearch

John H. Klungness; Roland Gleisner; Doreen Mann; Karen L. Scallon; J.Y. Zhu; Eric G. Horn; Louis L. Edwards

2005-01-01

We used SilviScan analysis and tracheid measurement to evaluate the effect of suppressed growth on the fundamental properties of wood fiber. Suppressed growth reduced cell tracheid length, but the high content of mature wood may translate into longer fibers overall. In pilot-scale refining experiments, blending 25% chips from small-diameter trees (SMD) with 75% mill...

Methods for reducing exposure to cotton dust. Progress report, 1 January 1981-30 September 1982

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hersh, S.P.; Batra, S.K.

1982-01-01

The effectiveness of additives and the blending of fibers on dust emission during carding, the relationship between dust-particle size and grade of cotton, and amount of oil mist in dust from treated cottons were investigated. Six additives were evaluated for dust-suppressant abilities on high-micronaire cotton. A substantial reduction in dust generated was achieved by the addition of very small amounts of five of the additives. For polyester and cotton blends, the dust generated increased as the cotton content of the blend increased and as the production rate increased.

Physical, chemical, and sensory properties of biscuits prepared from flour blends of unripe cooking banana, pigeon pea, and sweet potato.

PubMed

Adeola, Abiodun A; Ohizua, Ehimen R

2018-05-01

Biscuits were produced from 14 flour blends of cooking banana (UBF), pigeon pea (PPF), and sweet potato (SPF). The physical properties, nutrient composition, and sensory characteristics of the biscuits were evaluated using standard methods. Data obtained were subjected to analysis of variance, and mean values were separated using Duncan's multiple range test. The hardness of the biscuit samples decreased as PPF increased, while the fracturability decreased with increase in UBF. Biscuits were significantly ( p  < .05) different in their nutrient composition, with the crude protein, crude fiber, ash contents, and dietary fiber content increasing as the PPF level increased. Cookies were rich in magnesium (576.54-735.06 mg/100 g) with favorable Na/K ratio (<1.0). The antinutritional factors in the biscuit samples were within permissible levels. Biscuits prepared from flour blend of 21.67% unripe cooking banana, 21.67% pigeon pea, and 56.67% sweet potato were the most preferred in terms of shape, mouthfeel, taste, crunchiness, and overall acceptability. Flour blends of unripe cooking banana, pigeon pea, and sweet potato could therefore be used as raw materials for the production of biscuits, with high protein, total dietary, and energy content.

Microstructured Polymer Blend Surfaces Produced by Spraying Functional Copolymers and Their Blends

PubMed Central

Vargas-Alfredo, Nelson; Rodríguez Hernández, Juan

2016-01-01

We described the fabrication of functional and microstructured surfaces from polymer blends by spray deposition. This simple technique offers the possibility to simultaneously finely tune the microstructure as well as the surface chemical composition. Whereas at lower polymer concentration, randomly distributed surface micropatterns were observed, an increase of the concentration leads to significant changes on these structures. On the one hand, using pure homopolystyrene fiber-like structures were observed when the polymer concentration exceeded 30 mg/mL. Interestingly, the incorporation of 2,3,4,5,6-pentafluorostyrene changed the morphology, and, instead of fibers, micrometer size particles were identified at the surface. These fluorinated microparticles provide superhydrophobic properties leading to surfaces with contact angles above 165°. Equally, in addition to the microstructures provided by the spray deposition, the use of thermoresponsive polymers to fabricate interfaces with responsive properties is also described. Contact angle measurements revealed variations on the surface wettability upon heating when blends of polystyrene and polystyrene-b-poly(dimethylaminoethyl methacrylate) are employed. Finally, the use of spraying techniques to fabricate gradient surfaces is proposed. Maintaining a constant orientation, the surface topography and thus the contact angle varies gradually from the center to the edge of the film depending on the spray angle. PMID:28773555

Hollow fibers of poly(lactide-co-glycolide) and poly(ε-caprolactone) blends for vascular tissue engineering applications.

PubMed

Diban, Nazely; Haimi, Suvi; Bolhuis-Versteeg, Lydia; Teixeira, Sandra; Miettinen, Susanna; Poot, André; Grijpma, Dirk; Stamatialis, Dimitrios

2013-05-01

At present the manufacture of small-diameter blood vessels is one of the main challenges in the field of vascular tissue engineering. Currently available vascular grafts rapidly fail due to development of intimal hyperplasia and thrombus formation. Poly(lactic-co-glycolic acid) (PLGA) hollow fiber (HF) membranes have previously been proposed for this application, but as we show in the present work, they have an inhibiting effect on cell proliferation and rather poor mechanical properties. To overcome this we prepared HF membranes via phase inversion using blends of PLGA with poly(ε-caprolactone) (PCL). The influence of polymer composition on the HF physicochemical properties (topography, water transport and mechanical properties) and cell attachment and proliferation were studied. Our results show that only the ratio PCL/PLGA of 85/15 (PCL/PLGA85/15) yielded a miscible blend after processing. A higher PLGA concentration in the blend led to immiscible PCL/PLGA phase-separated HFs with an inhomogeneous morphology and variation in the cell culture results. In fact, the PCL/PLGA85/15 blend, which had the most homogeneous morphology and suitable pore structure, showed better human adipose stem cell (hASC) attachment and proliferation compared with the homopolymers. This, combined with the good mechanical and transport properties, makes them potentially useful for the development of small-caliber vascular grafts. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Chitosan Nanofibers for Transbuccal Insulin Delivery

PubMed Central

Lancina, Michael G.; Shankar, Roopa Kanakatti; Yang, Hu

2017-01-01

Purpose In this work, we aimed at producing chitosan based nanofiber mats capable of delivering insulin via the buccal mucosa. Methods Chitosan was electrospun into nanofibers using poly (ethylene oxide) (PEO) as a carrier molecule in various feed ratios. The mechanical properties and degradation kinetics of the fibers were measured. Insulin release rates were determined in vitro using an ELISA assay. The bioactivity of released insulin was measured in terms of Akt activation in pre-adipocytes. Insulin permeation across the buccal mucosa was measured in an ex-vivo porcine transbuccal model. Results Fiber morphology, mechanical properties, and in vitro stability were dependent on PEO feed ratio. Lower PEO content blends produced smaller diameter fibers with significantly faster insulin release kinetics. Insulin showed no reduction in bioactivity due to electrospinning. Buccal permeation of insulin facilitated by high chitosan content blends was significantly higher than that of free insulin. Conclusions Taken together, our work demonstrates chitosan based nanofibers have the potential to serve as a transbuccal insulin delivery vehicle. PMID:28000386

Controlled release of tocopherols from polymer blend films

NASA Astrophysics Data System (ADS)

Obinata, Noe

Controlled release packaging has great potential to increase storage stability of foods by releasing active compounds into foods continuously over time. However, a major limitation in development of this technology is the inability to control the release and provide rates useful for long term storage of foods. Better understanding of the factors affecting active compound release is needed to overcome this limitation. The objective of this research was to investigate the relationship between polymer composition, polymer processing method, polymer morphology, and release properties of active compounds, and to provide proof of principle that compound release is controlled by film morphology. A natural antioxidant, tocopherol was used as a model active compound because it is natural, effective, heat stable, and soluble in most packaging polymers. Polymer blend films were produced from combination of linear low density polyethylene (LLDPE) and high density polyethylene (HDPE), polypropylene (PP), or polystyrene (PS) with 3000 ppm mixed tocopherols using conventional blending method and innovative blending method, smart blending with a novel mixer using chaotic advection. Film morphologies were visualized with scanning electron microscopy (SEM). Release of tocopherols into 95% ethanol as a food simulant was measured by UV/Visible spectrophotometry or HPLC, and diffusivity of tocopherols in the polymers was estimated from this data. Polymer composition (blend proportions) and processing methods have major effects on film morphology. Four different types of morphologies, dispersed, co-continuous, fiber, and multilayer structures were developed by either conventional extrusion or smart blending. With smart blending of fixed polymer compositions, different morphologies were progressively developed with fixed polymer composition as the number of rod rotations increased, providing a way to separate effects of polymer composition and morphology. The different morphologies obtained using conventional and smart blending greatly affected tocopherol release. Strong correlation was observed between morphology and release rate: multilayer, slow release; co-continuous and fiber, moderate; disperse: fast release. Results indicate that morphology can be manipulated by polymer composition and processing method, and release rates of tocopherols are varied with polymer morphology. Manipulating polymer compositions and film morphologies may provide a means to control the release of tocopherols from food contact films.

Blackbody material

DOEpatents

Lauf, Robert J.; Hamby, Jr., Clyde; Akerman, M. Alfred; Trivelpiece, Alvin W.

1994-01-01

A light emitting article comprises a composite of carbon-bonded carbon fibers, prepared by: blending carbon fibers with a carbonizable organic powder to form a mixture; dispersing the mixture into an aqueous slurry; vacuum molding the aqueous slurry to form a green article; drying and curing the green article to form a cured article; and, carbonizing the cured article at a temperature of at least about 1000.degree. C. to form a carbon-bonded carbon fiber light emitting composite article having a bulk density less than 1 g/cm.sup.3.

Synthesis of Keratin-based Nanofiber for Biomedical Engineering.

PubMed

Thompson, Zanshe S; Rijal, Nava P; Jarvis, David; Edwards, Angela; Bhattarai, Narayan

2016-02-07

Electrospinning, due to its versatility and potential for applications in various fields, is being frequently used to fabricate nanofibers. Production of these porous nanofibers is of great interest due to their unique physiochemical properties. Here we elaborate on the fabrication of keratin containing poly (ε-caprolactone) (PCL) nanofibers (i.e., PCL/keratin composite fiber). Water soluble keratin was first extracted from human hair and mixed with PCL in different ratios. The blended solution of PCL/keratin was transformed into nanofibrous membranes using a laboratory designed electrospinning set up. Fiber morphology and mechanical properties of the obtained nanofiber were observed and measured using scanning electron microscopy and tensile tester. Furthermore, degradability and chemical properties of the nanofiber were studied by FTIR. SEM images showed uniform surface morphology for PCL/keratin fibers of different compositions. These PCL/keratin fibers also showed excellent mechanical properties such as Young's modulus and failure point. Fibroblast cells were able to attach and proliferate thus proving good cell viability. Based on the characteristics discussed above, we can strongly argue that the blended nanofibers of natural and synthetic polymers can represent an excellent development of composite materials that can be used for different biomedical applications.

Dairy fat blends high in α-linolenic acid are superior to n-3 fatty-acid-enriched palm oil blends for increasing DHA levels in the brains of young rats.

PubMed

Du, Qin; Martin, Jean-Charles; Agnani, Genevieve; Pages, Nicole; Leruyet, Pascale; Carayon, Pierre; Delplanque, Bernadette

2012-12-01

Achieving an appropriate docosahexaenoic acid (DHA) status in the neonatal brain is an important goal of neonatal nutrition. We evaluated how different dietary fat matrices improved DHA content in the brains of both male and female rats. Forty rats of each gender were born from dams fed over gestation and lactation with a low α-linolenic acid (ALA) diet (0.4% of fatty acids) and subjected for 6 weeks after weaning to a palm oil blend-based diet (10% by weight) that provided either 1.5% ALA or 1.5% ALA and 0.12% DHA with 0.4% arachidonic acid or to an anhydrous dairy fat blend that provided 1.5% or 2.3% ALA. Fatty acids in the plasma, red blood cells (RBCs) and whole brain were determined by gas chromatography. The 1.5% ALA dairy fat was superior to both the 1.5% ALA palm oil blends for increasing brain DHA (14.4% increase, P<.05), and the 2.3% ALA dairy blend exhibited a further increase that could be ascribed to both an ALA increase and n-6/n-3 ratio decrease. Females had significantly higher brain DHA due to a gender-to-diet interaction, with dairy fats attenuating the gender effect. Brain DHA was predicted with a better accuracy by some plasma and RBC fatty acids when used in combination (R(2) of 0.6) than when used individually (R(2)=0.47 for RBC n-3 docosapentaenoic acid at best). In conclusion, dairy fat blends enriched with ALA appear to be an interesting strategy for achieving optimal DHA levels in the brain of postweaning rats. Human applications are worth considering. Copyright © 2012 Elsevier Inc. All rights reserved.

Dietary fiber and flavan-3-ols in shortbread biscuits enriched with barley flours co-products.

PubMed

Verardo, Vito; Riciputi, Ylenia; Messia, Maria Cristina; Vallicelli, Melania; Falasca, Luisa; Marconi, Emanuele; Caboni, Maria Fiorenza

2011-05-01

The coarse fraction obtained by air classification of barley flour, rich in dietary fiber and flavan-3-ols, was utilized to develop functional biscuits. The flavan-3-ol content, antioxidant activity and oxidative stability of biscuits were measured during storage under retail conditions for 1 year. The replacement of 60% (w/w) refined wheat flour with barley coarse fraction increased the ash, fiber and flavan-3-ol contents significantly. Biscuit samples enriched with barley coarse fraction had a significantly higher amount of fiber compared with the control sample (six times higher). The β-glucan content in enriched samples was 15 times higher than control samples. The flavan-3-ol loss in biscuits after baking was about 67%. The initial content of flavan-3-ols increased from 0.6 to 4.3 mg/100 g in biscuits formulated with barley coarse fraction and showed improved antioxidant properties. Lipid oxidation increased during the shelf-life; the enriched biscuit showed the higher lipid oxidation status, but the level reached during the shelf-life was lower than the limit of acceptance reported for bakery products and, for this reason, does not compromise the safety.

Effect of a soluble cocoa fiber-enriched diet in Zucker fatty rats.

PubMed

Sánchez, David; Moulay, Leila; Muguerza, Begoña; Quiñones, Mar; Miguel, Marta; Aleixandre, Amaya

2010-06-01

The effects of a soluble cocoa fiber (SCF) were studied in Zucker fatty rats. Two groups of Zucker fatty rats were fed the following diets: standard diet and 5% SCF-enriched diet. A group of Zucker lean rats fed the standard diet was used for results comparison with obese Zucker animals. Solid and liquid intakes, body weight, plasma glucose, lipid profile, and systolic (SBP) and diastolic (DBP) blood pressure were recorded weekly. At the end of the experimental period insulin was determined, and fat apparent digestibility (FAD) and insulin resistance were calculated. The Zucker fatty rats fed 5% SCF-enriched diet showed less weight gain and food intake than those fed the standard diet. The group fed the fiber-enriched diet showed lower values of the total cholesterol/high-density lipoprotein cholesterol ratio and triglyceride levels than the standard group. FAD was also lower in the fiber group. Both SBP and DBP were decreased. In addition, SCF reduced plasma glucose and insulin, and as a consequence the insulin resistance was also decreased. Our data demonstrate that SCF resulted in an improvement of the studied risk factors associated with cardiometabolic disorders.

Low-energy route for alcohol/gasohol recovery from fermentor beer. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mix, T.W.

1982-03-01

The production of gasohol directly from fermentor beer and gasoline is feasible and will enable a major reduction in the energy requirements for gasohol production. The fermentor beer is first enriched in a beer still to a 69 mol % ethanol, 31 mol % water product which is then dehydrated by extractive distillation with gasoline as the extractive agent. Gasohol is produced directly. In one version of the process, a heavy cut of gasoline, presumed available at a refinery before blending in of light components, is used as the extractive agent. The enriching column overhead vapors are used to reboilmore » the extractive distillation and steam stripping columns and to contribute to the preheating of the fermentor beer feed. Light components are blended into the heavy cut-ethanol bottom product from the extractive distillation column to form the desired gasohol. Energy requirements, including feed preheat, are 11,000 Btu per gallon of ethanol in the product gasohol. One hundred and fifty pound steam is required. In a second version, full range gasoline is used as the extractive agent. The enriching column overhead vapors are again used to reboil the extractive distillation and steam stripping columns and to contribute to the preheating of the fermentor beer feed. Light gasoline components recovered from the decanter following the overhead condenser of the extractive distillation column are blended in with the gasoline-ethanol product leaving the bottom of the extractive distillation column to form the desired gasohol. Energy requirements in this case are 13,000 Btu/gallon of ethanol in the product gasohol. In both of the above cases it is energy-conservative and desirable from a process standpoint to feed the enriched alcohol to the extractive distillation column as a liquid rather than as a vapor.« less

Production of silk sericin/silk fibroin blend nanofibers

PubMed Central

2011-01-01

Silk sericin (SS)/silk fibroin (SF) blend nanofibers have been produced by electrospinning in a binary SS/SF trifluoroacetic acid (TFA) solution system, which was prepared by mixing 20 wt.% SS TFA solution and 10 wt.% SF TFA solution to give different compositions. The diameters of the SS/SF nanofibers ranged from 33 to 837 nm, and they showed a round cross section. The surface of the SS/SF nanofibers was smooth, and the fibers possessed a bead-free structure. The average diameters of the SS/SF (75/25, 50/50, and 25/75) blend nanofibers were much thicker than that of SS and SF nanofibers. The SS/SF (100/0, 75/25, and 50/50) blend nanofibers were easily dissolved in water, while the SS/SF (25/75 and 0/100) blend nanofibers could not be completely dissolved in water. The SS/SF blend nanofibers could not be completely dissolved in methanol. The SS/SF blend nanofibers were characterized by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry, and differential thermal analysis. FTIR showed that the SS/SF blend nanofibers possessed a random coil conformation and ß-sheet structure. PMID:21867508

Polymer alloys with balanced heat storage capacity and engineering attributes and applications thereof

DOEpatents

Soroushian, Parviz

2002-01-01

A thermoplastic polymer of relatively low melt temperature is blended with at least one of thermosets, elastomers, and thermoplastics of relatively high melt temperature in order to produce a polymer blend which absorbs relatively high quantities of latent heat without melting or major loss of physical and mechanical characteristics as temperature is raised above the melting temperature of the low-melt-temperature thermoplastic. The polymer blend can be modified by the addition of at least one of fillers, fibers, fire retardants, compatibilisers, colorants, and processing aids. The polymer blend may be used in applications where advantage can be taken of the absorption of excess heat by a component which remains solid and retains major fractions of its physical and mechanical characteristics while absorbing relatively high quantities of latent heat.

Hydrogen effects on materials for CNG/H2 blends.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farese, David; Keller, Jay O.; Somerday, Brian P.

2010-09-01

No concerns for Hydrogen-Enriched Compressed Natural gas (HCNG) in steel storage tanks if material strength is < 950 MPa. Recommend evaluating H{sub 2}-assisted fatigue cracking in higher strength steels at H{sub 2} partial pressure in blend. Limited fatigue testing on higher strength steel cylinders in H{sub 2} shows promising results. Impurities in Compressed Natural Gas (CNG) (e.g., CO) may provide extrinsic mechanism for mitigating H{sub 2}-assisted fatigue cracking in steel tanks.

The addition effect of Tunisian date seed fibers on the quality of chocolate spreads.

PubMed

Bouaziz, Mohamed Ali; Abbes, Fatma; Mokni, Abir; Blecker, Christophe; Attia, Hamadi; Besbes, Souhail

2017-04-01

Novel chocolate spreads were enriched by soluble and insoluble dietary fibers from Tunisian Deglet Nour date seeds at 1, 2, 3, 4, and 5% levels in the conventional chocolate spread. Defatted Deglet Nour date seeds, date seed soluble fiber concentrate (DSSFC) and date seed insoluble fiber concentrate (DSIFC) were characterized by high levels of dietary fibers (80-90%). Chocolate spread enriched with 5% of DSSFC presented the highest oil binding capacity (304.62%) compared to the control (102%). Whatever the DSIFC and DSSFC incorporation levels, no significant difference was recorded between the firmness, chewiness, and adhesiveness of prepared chocolate spreads compared to the control (p < .05). Sensory evaluation revealed that all prepared chocolate spreads enriched by DSIFC and DSSFC were accepted by panelists. These results indicated the value of date seeds as new source of dietary fibers to develop chocolate spread and could also improve health benefits and functional properties. Tunisia is considered to be one of the dates-producing countries. The mean annual yield of date fruits is about 200,000 tons. From this, around 20,000 tons of date seeds could be collected. This by-product of date processing industries could be regarded as an excellent source of dietary fiber with interesting technological functionality and many beneficial effects on human health. Then, date seeds could present a value addition by extraction and use of date seed fiber concentrate in chocolate spread formulation. © 2016 Wiley Periodicals, Inc.

Cr-enriched yeast: beyond fibers for the management of postprandial glycemic response to bread.

PubMed

Yanni, Amalia E; Stamataki, Nikoleta; Stoupaki, Maria; Konstantopoulos, Panagiotis; Pateras, Irene; Tentolouris, Nikolaos; Perrea, Despoina; T Karathanos, Vaios

2017-06-01

Efforts regarding the amelioration of postprandial glycemic response to bread are mainly focused in the addition of soluble dietary fibers. The current study presents another approach which is based on the supplementation of flour with Cr-enriched yeast. Cr is known for its beneficial effects on improvement of glucose tolerance and enhancement of insulin sensitivity. Twelve normoglycemic subjects were provided with white bread (WB, reference food) or whole wheat bread with Cr-enriched yeast (WWCrB, rich in insoluble fibers) or white wheat bread with Cr-enriched yeast (WCrB, poor in fibers) or whole wheat-rye-barley bread enriched with oat beta glucans (BGB, rich in soluble fibers) with 1-week intervals in amounts that yielded 50 g of available carbohydrates. Postprandial glucose, insulin and ghrelin responses as well as glycemic index (GI) were evaluated. Ingestion of WWCrB, WCrB and BGB elicited lower incremental area under the curve (iAUC) for 120-min glycemic response compared to WB (1033.02 ± 282.32, 701.69 ± 330.86 and 748.95 ± 185.42 vs 2070.87 ± 518.44 mg/dL min, respectively, P < 0.05 for WCrB and BGB). The GI was calculated as 62.35 ± 11.78 for WWCrB, 34.22 ± 11.93 for WCrB and 37.90 ± 5.00 for BGB (P < 0.05 vs WB, GI = 100). iAUC for 120-min insulin response to BGB was significantly lower than WB (2780.04 ± 303.26 vs 3915.53 ± 490.57 μU/mL min, P < 0.05), while ghrelin remained suppressed for almost 120 min after the consumption of WWCrB and BGB. Supplementation of flour with Cr-enriched yeast induces milder postprandial glycemic response to bread without the necessity of high fiber amounts, providing with another strategy for the management of glycemic control.

Training High School Students in the Scientific Method via Hands On Projects in a Laboratory Environment

DTIC Science & Technology

2015-02-27

Poly(vinylidene Fluoride with Trifluoroethylene) P(VDF-TrFE) 75:25 Thin Films by Atomic Force Microscope Nanolithography, Scanning, (04 2012): 0...doi: 10.1002/sca.21024 William Serrano, Nicholas J. Pinto. Electrospun Fibers of Poly(Vinylidene Fluoride -Trifluoroethylene)/Poly (3-Hexylthiophene...Nicholas Pinto. Electrospun fibers of poly (vinylidene fluoride -trifluoroethylene)/ poly (3- hexylthiophene) blends from tetrahydrofuran, National

Optimization of process parameters for extrusion cooking of low amylose rice flour blended with seeded banana and carambola pomace for development of minerals and fiber rich breakfast cereal.

PubMed

Borah, Anjan; Lata Mahanta, Charu; Kalita, Dipankar

2016-01-01

The low-amylose rice flour, seeded banana (Musa balbisiana, ABB) and carambola (Averrhoa carambola L.) pomace blends were extruded to prepare ready to eat breakfast cereal in a single-screw extruder. Response surface methodology using a central composite design was used to evaluate effect of independent variables, namely blend ratio (80:10:10 - 60:30:10 of low-amylose rice flour, seeded banana and carambola pomace), screw speed (200 - 400 rpm), barrel temperature (90 - 130 (°)C) and feed moisture content (9 - 21 g/100 g, wet basis) on product responses. Quadratic polynomial equations were also obtained by multiple regression analysis. The predicted models were adequate based on lack-of-fit test and coefficient of determination obtained. The feed moisture content had critical effect on all response variables. The compromised optimal conditions obtained by numerical integration for development of extrudates were: screw speed of 350 rpm, barrel temperature of 120 (°)C, feed moisture content of 12 g/100 g and 65:25:10 of blend ratio of feed. In the optimized condition low-amylose rice blend is found to have better physicochemical properties (water absorption index of 481.79 g/100 g; water solubility index of 44.13 g/100 g) and dietary fiber content of 21.35 g/100 g respectively. The developed breakfast cereal showed considerable amount of minerals (Mg and K) and overall acceptability was found to be 7.8.

Performance Using Bamboo Fiber Ash Concrete as Admixture Adding Superplasticizer

NASA Astrophysics Data System (ADS)

Vasudevan, Gunalaan

2017-06-01

The increasing demand on natural resources for housing provisions in developing countries have called for sourcing and use of sustainable local materials for building and housing delivery. Natural materials to be considered sustainable for building construction should be ‘green’ and obtained from local sources, including rapidly renewable plant materials like palm fronds and bamboo, recycled materials and other products that are reusable and renewable. Each year, tens of millions of tons of bamboo are utilized commercially, generating a vast amount of waste. Besides that, bamboo fiber is easy availability, low density, low production cost and satisfactory mechanical properties. One solution is to activate this waste by using it as an additive admixture in concrete to keep it out of landfills and save money on waste disposal. The research investigates the mechanical and physical properties of bamboo fiber powder in a blended Portland cement. The structural value of the bamboo fiber powder in a blended Portland cement was evaluated with consideration for its suitability in concrete. Varied percentage of bamboo fiber powder (BFP) at 0%, 5%, 10%, 15%, and 20% as an admixture in 1:2:4 concrete mixes. The workability of the mix was determined through slump; standard consistency test was carried on the cement. Compressive strength of hardened cured (150 x 150 x 150) mm concrete cubes at 7days, 14days and 28days were tested.

Influence of polysaccharide-based edible coatings as carriers of prebiotic fibers on quality attributes of ready-to-eat fresh blueberries.

PubMed

Alvarez, María V; Ponce, Alejandra G; Moreira, María R

2018-05-01

Little information is available regarding the effect of dietary fibers added into edible coatings on quality attributes of ready-to-eat fruits. The aim of this study was to evaluate the effects of sodium alginate (AL) and chitosan (CH) edible coatings enriched with four different dietary fibers (apple fiber, orange fiber, inulin and oligofructose) on microbiological, nutritional, physico-chemical and sensorial properties of ready-to-eat fresh blueberries stored for 18 days at 5 °C. The most encouraging results were found for CH coatings (with and without fibers) which significantly inhibited the growth of mesophilic bacteria and yeasts/molds (reductions up to 1.9 log CFU g -1 ), reduced decay rate by more than 50%, enhanced antioxidant properties, retained fruit firmness, delayed off-odor development and improved overall visual quality of blueberries. Oligofructose and orange fiber added to CH coatings enhanced antioxidant properties of fruits and allowed higher reductions in yeast/mold counts compared to the use of CH alone. CH-based coatings enriched with inulin, oligofructose and apple fiber extended sensory shelf life of blueberries by 6 days. AL coatings (with and without fiber) allowed delaying fungal decay and also retaining antioxidant properties but did not improve the microbiological and sensory quality of fruits. The results proved that fiber-enriched CH treatments allowed the maintenance of freshness and the improvement of the quality of ready-to-eat blueberries. It might be an interesting option to offer consumers a healthy product with prebiotic potential and an extended shelf life. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Nutrient composition, functional, and pasting properties of unripe cooking banana, pigeon pea, and sweetpotato flour blends.

PubMed

Ohizua, Ehimen R; Adeola, Abiodun A; Idowu, Micheal A; Sobukola, Olajide P; Afolabi, T Adeniyi; Ishola, Raphael O; Ayansina, Simeon O; Oyekale, Tolulope O; Falomo, Ayorinde

2017-05-01

This study investigated some quality attributes of unripe cooking banana (UBF), pigeon pea (PPF), and sweetpotato (SPF) flour blends. Simplex centroid mixture design was used to obtain 17 blends from the flours. The nutrient composition, color, and functional properties of the blends were evaluated using standard methods. Data were subjected to analysis of variance and treatment means were compared using Duncan's multiple range test at 5% probability level. There were significant ( p  < .05) differences in the nutrient composition, and functional and pasting properties of the blends. The crude protein, crude fiber, ash, foaming capacity, emulsion capacity, and least gelation capacity of the blends increased as the PPF level increased. The blends had Na/K ratio of <1.0. The dispersibility, bulk density, water, and oil absorption capacities of the blends increased as SPF and UBF increased. The peak, setback, and final viscosities increased as UBF and SPF inclusion increased,whereas pasting temperature and time increased as the PPF level increased. The L*, a*, and b* values of the flour blends which were significantly ( p  < .05) different ranged from 79.58 to 102.71, -0.15 to 2.79, and 13.82 to 23.69, respectively. Cooking banana-pigeon pea-sweetpotato flour blends are desirable for alleviating malnutrition in Nigeria and developing new food formulations.

Damage tolerant light absorbing material

DOEpatents

Lauf, Robert J.; Hamby, Jr., Clyde; Akerman, M. Alfred; Seals, Roland D.

1993-01-01

A light absorbing article comprised of a composite of carbon-bonded carbon fibers, prepared by: blending carbon fibers with a carbonizable organic powder to form a mixture; dispersing the mixture into an aqueous slurry; vacuum molding the aqueous slurry to form a green article; drying and curing the green article to form a cured article; and, carbonizing the cured article at a temperature of at least about 1000.degree. C. to form a carbon-bonded carbon fiber light absorbing composite article having a bulk density less than 1 g/cm.sup.3.

Damage tolerant light absorbing material

DOEpatents

Lauf, R.J.; Hamby, C. Jr.; Akerman, M.A.; Seals, R.D.

1993-09-07

A light absorbing article comprised of a composite of carbon-bonded carbon fibers, is prepared by: blending carbon fibers with a carbonizable organic powder to form a mixture; dispersing the mixture into an aqueous slurry; vacuum molding the aqueous slurry to form a green article; drying and curing the green article to form a cured article; and, carbonizing the cured article at a temperature of at least about 1000 C to form a carbon-bonded carbon fiber light absorbing composite article having a bulk density less than 1 g/cm[sup 3]. 9 figures.

Effect of dietary nutrients on ileal endogenous losses of threonine, cysteine, methionine, lysine, leucine and protein in broiler chicks.

PubMed

Cerrate, S; Vignale, S K; Ekmay, R; England, J; Coon, C

2018-04-01

An isotope dose technique was utilized (i) to determine endogenous amino acid (AA) and protein losses and (ii) to propose adjusted values for AA requirements. The endogenous flow rate was calculated from the pool of enrichment in plasma AA, assuming similitude to enrichment of endogenous AA. In experiment 1, chicks were orally administered D4-lysine at 2% of estimated lysine intake from 16 to 24 days to find the isotopic steady state of the atom percent excess (APE) of lysine for plasma and jejunal and ileal digesta. The APE of D4-lysine in plasma, jejunal digesta and ileal digesta reached the isotopic steady state at 5.5, 3.4 and 2.0 days, respectively, by using the broken-line model. It was assumed that the isotopic steady state at 5 days identified for D4-lysine is also representative for the 15N-labeled AA. In experiment 2, chicks were fed diets from 1 to 21 days with increasing levels of fat (6%, 8%, 12%, 13% extract ether), protein (26%, 28.5%, 31% CP) or fiber (14%, 16%, 18% NDF) by adding poultry fat, soybean meal, blended animal protein or barley. Chicks were orally administered 15N-threonine, 15N-cysteine, 15N-methionine, 15N-lysine and 15N-leucine at 2% of estimated daily intake for 5 days from 17 to 21 days of age. Dietary nutrients influenced endogenous losses (EL), where dietary fat stimulated EL of lysine (P=0.06), leucine and protein (P=0.07); dietary protein enhanced EL of leucine and protein; and finally the dietary fiber increased EL of leucine. Dietary nutrients also affected apparent ileal digestibility (AID). Dietary fat increased AID of cysteine but decreased AID of lysine. Dietary protein reduced AID of protein, threonine, lysine and leucine, and similarly dietary fiber decreased AID of protein, threonine, methionine, lysine and leucine. In contrast, dietary fat or protein did not affect real ileal digestibility (RID) of protein and AA except threonine and leucine. The dietary fiber reduced the RID of protein, threonine and leucine. This indicate that variations of some endogenous AA and protein losses due to dietary nutrients almost eliminates the effects of RID, and thus the EL coming from the body should be utilized to adjust the AA requirement instead of changing the true digestible nutrients of ingredients. The present data suggest that 5 days' feeding labeled AA was enough to reach the isotopic steady state and AA requirements should be adjusted when additional dietary protein, fat or fiber is fed.

Organic Biochar Based Fertilization

NASA Astrophysics Data System (ADS)

Schmidt, Hans-Peter; Pandit, Bishnu Hari; Cornelissen, Gerard; Kammann, Claudia

2017-04-01

Biochar produced in cost-efficient flame curtain kilns (Kon-Tiki) was nutrient enriched either with cow urine or with dissolved mineral (NPK) fertilizer to produce biochar-based fertilizers containing between 60-100 kg N, 5-60 kg P2O5 and 60-100 kg K2O, respectively, per ton of biochar. In 21 field trials nutrient-enriched biochars were applied at rates of 0.5 to 2 t ha-1 into the root zone of 13 different annual and perennial crops. Treatments combining biochar, compost and organic or chemical fertilizer were evaluated; control treatments contained the same amounts of nutrients but without biochar. All nutrient-enriched biochar substrates improved yields compared to their respective no-biochar controls. Biochar enriched with dissolved NPK produced on average 20% ± 5.1% (N=4) higher yields than standard NPK fertilization without biochar. Cow urine-enriched biochar blended with compost resulted on average in 123% ± 76.7% (N=13) higher yields compared to the organic farmer practice with cow urine-blended compost and outcompeted NPK-enriched biochar (same nutrient dose) by 103% ± 12.4% (N=4) on average. 21 field trials robustly revealed that low-dosage root zone application of organic biochar-based fertilizers caused substantial yield increases in rather fertile silt loam soils compared to traditional organic fertilization and to mineral NPK- or NPK-biochar fertilization. This can likely be explained by the nutrient carrier effect of biochar causing a slow nutrient release behavior, more balanced nutrient fluxes and reduced nutrient losses especially when liquid organic nutrients are used for the biochar enrichment. The results promise new pathways for optimizing organic farming and improving on-farm nutrient cycling.

Stretchable Fluorescent Polyfluorene/Acrylonitrile Butadiene Rubber Blend Electrospun Fibers through Physical Interaction and Geometrical Confinement.

PubMed

Hsieh, Hui-Ching; Chen, Jung-Yao; Lee, Wen-Ya; Bera, Debaditya; Chen, Wen-Chang

2018-03-01

Stretchable light-emitting polymers are important for wearable electronics; however, the development of intrinsic stretchable light-emitting materials with great performance under large applied strain is the most critical challenge. Herein, this study demonstrates the fabrication of stretchable fluorescent poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctyl-fluorene)]/acrylonitrile butadiene rubber (PFN/NBR) blend nanofibers using the uniaxial electrospinning technique. The physical interaction of PFN with NBR and the geometrical confinement of nanofibers are employed to reduce PFN aggregation, leading to the high photoluminescence quantum yield of 35.7%. Such fiber mat film shows stable blue emission at the 50% strain for 200 stretching/release cycles, which has potential applications in smart textiles. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Poly(L-lactide) and poly(butylene succinate) immiscible blends: from electrospinning to biologically active materials.

PubMed

Stoyanova, Nikoleta; Paneva, Dilyana; Mincheva, Rosica; Toncheva, Antoniya; Manolova, Nevena; Dubois, Philippe; Rashkov, Iliya

2014-08-01

For the first time the preparation of defect-free fibers from immiscible blends of high molar mass poly(lactic acid) (PLA) and poly(butylene succinate) (PBS) in the whole range of the polyester weight ratios is shown. Electrospinning using the solvent-nonsolvent approach proved most appropriate. Moreover, electrospinning revealed crucial for the obtaining of PLA/PBS materials maintaining integrity. DSC and XRD analyses attested for a plasticizing effect and for increased PLA crystallinity at PBS addition to PLA. The mechanical properties of the PLA/PBS mats were controlled by the alignment of the fibers and changed from plastic to brittle materials upon increasing the PBS content. Drug loading and tests against pathogenic microorganisms suggested that the obtained mats can find application as antibacterial fibrous materials. Copyright © 2014 Elsevier B.V. All rights reserved.

The behavior of MC3T3-E1 cells on chitosan/poly-L-lysine composite films: effect of nanotopography, surface chemistry, and wettability.

PubMed

Zheng, Zhenhuan; Zhang, Ling; Kong, Lijun; Wang, Aijun; Gong, Yandao; Zhang, Xiufang

2009-05-01

In the present work, a series of composite films were produced from chitosan/poly-L-lysine blend solutions. The surface topography, chemistry, and wettability of composite films were characterized by atomic force microscopy (AFM), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and contact angle assay, respectively. For all composite films, blending with poly-L-lysine induced changes in surface chemistry and wettability. Interestingly, it was also found that increasing poly-L-lysine weight fraction in blend solutions could result in different nanoscaled surface topographic features, which displayed particle-, granule-, or fiber-dominant morphologies. MC3T3-E1 osteoblast-like cells were cultured on all composite films to evaluate the effects of surface nanotopography, chemistry, and wettability on cell behavior. The observations indicated that MC3T3-E1 cell behavior was affected by surface topography, chemistry, and wettability simultaneously and that cells showed strong responses to surface topography. On fiber-dominant surface, cells fully spread with obvious cytoskeleton organization and exhibited significantly higher level of adhesion and proliferation compared with particle- or granule-dominant surfaces. Furthermore, fiber-dominant surface also induced greater expression of mature osteogenic marker osteocalcin and higher mineralization based on RT-PCR and von Kossa staining. The results suggest that topographic modification of chitosan substratum at the nanoscale may be exploited in regulating cell behavior for its applications in tissue engineering.

Pectinmethylesterases (PME) and pectinmethylesterase inhibitors (PMEI) enriched during phloem fiber development in flax (Linum usitatissimum).

PubMed

Pinzon-Latorre, David; Deyholos, Michael K

2014-01-01

Flax phloem fibers achieve their length by intrusive-diffusive growth, which requires them to penetrate the extracellular matrix of adjacent cells. Fiber elongation therefore involves extensive remodelling of cell walls and middle lamellae, including modifying the degree and pattern of methylesterification of galacturonic acid (GalA) residues of pectin. Pectin methylesterases (PME) are important enzymes for fiber elongation as they mediate the demethylesterification of GalA in muro, in either a block-wise fashion or in a random fashion. Our objective was to identify PMEs and PMEIs that mediate phloem fiber elongation in flax. For this purpose, we measured transcript abundance of candidate genes at nine different stages of stem and fiber development and found sets of genes enriched during fiber elongation and maturation as well as during xylem development. We expressed one of the flax PMEIs in E. coli and demonstrated that it was able to inhibit most of the native PME activity in the upper portion of the flax stem. These results identify key genetic components of the intrusive growth process and define targets for fiber engineering and crop improvement.

Efficient technical solution for recycling textile materials by manufacturing nonwoven geotextiles

NASA Astrophysics Data System (ADS)

Leon, A. L.; Potop, G. L.; Hristian, L.; Manea, L. R.

2016-08-01

This paper aims to support the concept "circular economy" that was developed recently. It presents an efficient method for creating a closed loop in the Romanian textile industry by recycling textile materials, such as polyacrylonitrile knitted old products (collected from population) and small polyester woven patches from pre-consumer waste (garments manufacturing companies). Because of their properties, nonwoven geotextiles have many advantages in railways reinforcement, slopes stabilization, erosion control, drainage, filtration, paving roads, crops coverings, etc. The nonwoven geotextiles were obtained from three fibrous blends based on recovered fibers (PES and PAN) and fibers at first usage (PP) in different ratios. All experimental variants were processed on the same manufacturing line with the same technological parameters. There were tested the main physical and mechanical parameters and it was applied single factor ANOVA method for thickness, bulk density, air permeability and static puncture strength. The conclusion is that adding PP fibers in the blends represents a very important factor for geotextiles characteristics but it possible to decrease the ratio from economical reasons and still maintain a high quality level of nonwovens.

Chitosan nanofibers for transbuccal insulin delivery.

PubMed

Lancina, Michael G; Shankar, Roopa Kanakatti; Yang, Hu

2017-05-01

In this work, they aimed at producing chitosan based nanofiber mats capable of delivering insulin via the buccal mucosa. Chitosan was electrospun into nanofibers using poly(ethylene oxide) (PEO) as a carrier molecule in various feed ratios. The mechanical properties and degradation kinetics of the fibers were measured. Insulin release rates were determined in vitro using an ELISA assay. The bioactivity of released insulin was measured in terms of Akt activation in pre-adipocytes. Insulin permeation across the buccal mucosa was measured in an ex-vivo porcine transbuccal model. Fiber morphology, mechanical properties, and in vitro stability were dependent on PEO feed ratio. Lower PEO content blends produced smaller diameter fibers with significantly faster insulin release kinetics. Insulin showed no reduction in bioactivity due to electrospinning. Buccal permeation of insulin facilitated by high chitosan content blends was significantly higher than that of free insulin. Taken together, the work demonstrates that chitosan-based nanofibers have the potential to serve as a transbuccal insulin delivery vehicle. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1252-1259, 2017. © 2017 Wiley Periodicals, Inc.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanadi, A.R.; Caulfield, D.F.; Jacobson, R.E.

Kenaf (Hibiscus Cannabinus) is a fast growing annual growth plant that is harvested for its bast fibers. These fibers have excellent specific properties and have potential to be outstanding reinforcing fillers in plastics. In our experiments, the fibers and polypropylene (PP) were blended in a thermokinetic mixer and then injection molded, with the fiber weight fractions varying to 60%. A maleated polypropylene was used to improve the interaction and adhesion between the non-polar matrix and the polar lignocellulosic fibers. The specific tensile and flexural moduli of a 50 % by volume (39 % by volume) of kenaf-PP composites compares favorablymore » with a 40 % by weight of glass fiber-PP injection molded composites, These results suggest that kenaf fibers are a viable alternative to inorganic/mineral based reinforcing fibers as long as the right processing conditions are used and for applications where the higher water absorption is not critical.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sanadi, A.R.; Caulfield, D.F.; Jacobson, R.E.

Kenaf (Hibiscus cannabinus) is a fast growing annual growth plant that is harvested for its bast fibers. These fibers have excellent specific properties and have potential to be outstanding reinforcing fillers in plastics. In these experiments, the fibers and polypropylene (PP) were blended in a thermokinetic mixer and then injection molded, with the fiber weight fractions varying to 60%. A maleated polypropylene was used to improve the interaction and adhesion between the nonpolar matrix and the polar lignocellulosic fibers. The specific tensile and flexural moduli of a 50% by weight (39% by volume) of kenaf-PP composite compare favorably with amore » 40% by weight of glass fiber-PP injection-molded composite. These results suggest that kenaf fibers are a viable alternative to inorganic/mineral-based reinforcing fibers as long as the right processing conditions are used and they are used in applications where the higher water absorption is not critical.« less

Effects of a Bioavailable Arabinoxylan-enriched White Bread Flour on Postprandial Glucose Response in Normoglycemic Subjects.

PubMed

Giulia Falchi, Anna; Grecchi, Ilaria; Muggia, Chiara; Palladini, Giuseppina; Perlini, Stefano

2016-11-01

The beneficial effects of soluble fibers on carbohydrate metabolism are well documented. In this regard, we tested an arabinoxylan-enriched white bread flour, obtained by a patented process by which the bran extracted from the milling process is enzymatically hydrolyzed in order to separate the soluble fraction fiber from the insoluble fiber. We recruited 24 healthy normoglycemic volunteers [Age 34-61 ± 12.5 y; Body Mass Index (BMI) 22.1 ± 2.5 kg/m(2); Waist circumference (WC) 84.43 ± 8.0 cm; Fat Mass (FM) 22.7 ± 8.0%] attending the Dietetics Outpatient Clinic of the Internal Medicine Department at IRCCS Policlinico S. Matteo Foundation, University of Pavia, Pavia, Italy. Subjects acutely consumed arabinoxylan-enriched white bread (weight: 100 g) or isoenergetic control breads, in a double-blind crossover study design. Plasma glucose levels were measured just before bread administration and 30 minutes afterwards. The 30-minute peak postprandial glucose concentrations after arabinoxylan-enriched meals were significantly lower than after the control meal (107±4.6 mg/dL vs. 121 ± 5.2 mg/dL; p < 0.05). The here-reported results show how postprandial glucose responses were improved by ingestion of the arabinoxylan-enriched meal. Further studies are needed to clarify whether daily consumption of arabinoxylan-enriched bread will benefit patients with type 2 diabetes mellitus.

Heat-shrink tubing as a solid-phase microextraction coating for the enrichment and determination of phthalic acid esters.

PubMed

Luo, Xi; He, Chengxia; Zhang, Feifang; Wang, Hailong; Yang, Bingcheng; Liang, Xinmiao

2014-12-01

Heat-shrink tubing, which shrinks in one plane only (its diameter) when heated, commonly used for sealing protection in electrical engineering, was found to be able to function as a solid-phase microextraction coating. Its utility was demonstrated for the determination of phthalic acid esters in an aqueous solution combined with high-performance liquid chromatography equipped with a UV absorbance detector. The preparation procedure was rather simple and only ∼10 min was needed. The fiber cost is extremely low (∼10 cent each). The parameters affecting the extraction were optimized. Heat-shrink tubing fiber exhibited a significant enrichment effect for the three examined phthalic acid esters and up to 931-fold enrichment factor was obtained. The limit of detection was <10 μg/L for all analytes. The operation repeatability and fiber-to-fiber reproducibility were 1.2-8.3 and 5.4-9.1%, respectively. It was successfully applied for the analysis of bottled drinking water with recoveries ranging from 90.1-100.5%. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Transmissible microbial and metabolomic remodeling by soluble dietary fiber improves metabolic homeostasis

PubMed Central

He, Baokun; Nohara, Kazunari; Ajami, Nadim J.; Michalek, Ryan D.; Tian, Xiangjun; Wong, Matthew; Losee-Olson, Susan H.; Petrosino, Joseph F.; Yoo, Seung-Hee; Shimomura, Kazuhiro; Chen, Zheng

2015-01-01

Dietary fibers are increasingly appreciated as beneficial nutritional components. However, a requisite role of gut microbiota in fiber function and the overall impact of fibers on metabolomic flux remain unclear. We herein showed enhancing effects of a soluble resistant maltodextrin (RM) on glucose homeostasis in mouse metabolic disease models. Remarkably, fecal microbiota transplantation (FMT) caused pronounced and time-dependent improvement in glucose tolerance in RM recipient mice, indicating a causal relationship between microbial remodeling and metabolic efficacy. Microbial 16S sequencing revealed transmissible taxonomic changes correlated with improved metabolism, notably enrichment of probiotics and reduction of Alistipes and Bacteroides known to associate with high fat/protein diets. Metabolomic profiling further illustrated broad changes, including enrichment of phenylpropionates and decreases in key intermediates of glucose utilization, cholesterol biosynthesis and amino acid fermentation. These studies elucidate beneficial roles of RM-dependent microbial remodeling in metabolic homeostasis, and showcase prevalent health-promoting potentials of dietary fibers. PMID:26040234

Crystallization kinetics and thermal resistance of bamboo fiber reinforced biodegradable polymer composites

NASA Astrophysics Data System (ADS)

Thumsorn, S.; Srisawat, N.; On, J. Wong; Pivsa-Art, S.; Hamada, H.

2014-05-01

Bamboo fiber reinforced biodegradable polymer composites were prepared in this study. Biodegradable poly(butylene succinate) (PBS) was blended with bamboo fiber in a twin screw extruder with varied bamboo content from 20-0wt%. PBS/bamboo fiber composites were fabricated by compression molding process. The effect of bamboo fiber contents on properties of the composites was investigated. Non-isothermal crystallization kinetic study of the composites was investigated based on Avrami equation. The kinetic parameters indicated that bamboo fiber acted as heterogeneous nucleation and enhanced crystallinity of the composites. Bamboo fiber was well dispersed on PBS matrix and good adhered with the matrix. Tensile strength of the composites slightly deceased with adding bamboo fiber. However, tensile modulus and impact strength of the composites increased when increasing bamboo fiber contents. It can be noted that bamboo fiber promoted crystallization and crystallinity of PBS in the composites. Therefore, the composites were better in impact load transferring than neat PBS, which exhibited improving on impact performance of the composites.

Enrichment of reactive macerals in coal: its characterization and utilization in coke making

NASA Astrophysics Data System (ADS)

Nag, Debjani; Kopparthi, P.; Dash, P. S.; Saxena, V. K.; Chandra, S.

2018-01-01

Macerals in coal are of different types: reactive and inert. These macerals are differ in their physical and chemical properties. Column flotation method has been used to separate the reactive macerals in a non-coking coal. The enriched coal is then characterized in order to understand the changes in the coking potential by different techniques. It is then used in making of metallurgical coke by proper blending with other coals. Enriched coal enhance the properties of metallurgical coke. This shows a path of utilization of non-coking coal in metallurgical coke making.

The effect of guar gum and fiber-enriched wheat bran on gastric emptying of a semisolid meal in healthy subjects.

PubMed

Rydning, A; Berstad, A; Berstad, T; Hertzenberg, L

1985-04-01

The effect of physiological doses of guar gum (Guarem), 5 g, and fiber-enriched wheat bran (Fiberform), 10.5 g, on gastric emptying was studied by two different methods in healthy subjects: by a simple isotope localization monitor placed over the upper part of the abdomen and by gamma camera. The fiber preparations were added to a semisolid meal consisting of wheatmeal porridge and juice, using technetium-99 DTPA as a marker. The gamma camera showed no effect of fiber on gastric emptying. The isotope localization monitor, however, indicated that Fiberform prevented a postprandial accumulation of the meal within the upper part of the stomach. The simple isotope localization monitor cannot be recommended for measurements of gastric emptying.

Biological Templating and the Production of Functional Fibers

DTIC Science & Technology

2006-11-01

technique to express designed functional peptides on the virus surface is so-called phage display . It has been widely used to modify the virus surface...and functionality. By using the phage display technique, short peptides containing 2 to 12 random amino acids can be fused into pIII proteins to... M13 filamentous bacteriophage were spun into continuous microfibers. These fibers can be made out of pure phage solution or a blended solution of

Separation of Glucose and Pentose Sugars by Selective Enzyme Hydrolysis of AFEX-Treated Corn Fiber

NASA Astrophysics Data System (ADS)

Hanchar, Robert J.; Teymouri, Farzaneh; Nielson, Chandra D.; McCalla, Darold; Stowers, Mark D.

A process was developed to fractionate corn fiber into glucose- and pentose-rich fractions. Corn fiber was ammonia fiber explosion treated at 90°C, using 1 g anhydrous ammonia per gram of dry biomass, 60% moisture, and 30-min residence time. Twenty four hour hydrolysis of ammonia fiber explosion-treated corn fiber with cellulase converted 83% of available glucanto-glucose. In this hydrolysis the hemicellulose was partially broken down with 81% of the xylan and 68% of the arabinan being contained in the hydrolysate after filtration to remove lignin and other insoluble material. Addition of ethanol was used to precipitate and recover the solubilized hemicellulose from the hydrolysate, followed by hydrolysis with 2% (v/v) sulfuric acid to convert the recovered xylan and arabinan to monomeric sugars. Using this method, 57% of xylose and 54% of arabinose available in corn fiber were recovered in a pentose-rich stream. The carbohydrate composition of the pentose-enriched stream was 5% glucose, 57% xylose, 27% arabinose, and 11% galactose. The carbohydrate composition of the glucose-enriched stream was 87% glucose, 5% xylose, 6% arabinose, and 1% galactose, and contained 83% of glucose available from the corn fiber.

Can blended learning and the flipped classroom improve student learning and satisfaction in Saudi Arabia?

PubMed

Sajid, Muhammad R; Laheji, Abrar F; Abothenain, Fayha; Salam, Yezan; AlJayar, Dina; Obeidat, Akef

2016-09-04

To evaluate student academic performance and perception towards blended learning and flipped classrooms in comparison to traditional teaching. This study was conducted during the hematology block on year three students. Five lectures were delivered online only. Asynchronous discussion boards were created where students could interact with colleagues and instructors. A flipped classroom was introduced with application exercises. Summative assessment results were compared with previous year results as a historical control for statistical significance. Student feedback regarding their blended learning experience was collected. A total of 127 responses were obtained. Approximately 22.8% students felt all lectures should be delivered through didactic lecturing, while almost 35% felt that 20% of total lectures should be given online. Students expressed satisfaction with blended learning as a new and effective learning approach. The majority of students reported blended learning was helpful for exam preparation and concept clarification. However, a comparison of grades did not show a statistically significant increase in the academic performance of students taught via the blended learning method. Learning experiences can be enriched by adopting a blended method of instruction at various stages of undergraduate and postgraduate education. Our results suggest that blended learning, a relatively new concept in Saudi Arabia, shows promising results with higher student satisfaction. Flipped classrooms replace passive lecturing with active student-centered learning that enhances critical thinking and application, including information retention.

Production of corn fiber gum under conditions that retain its functional components

USDA-ARS?s Scientific Manuscript database

Corn fiber gum (CFG) is a hemicellulose (arabinoxylan)-enriched fraction obtained by the extraction of corn bran/fiber using a mild alkaline hydrogen peroxide process. The unique polysaccharide, CFG, with its low solution viscosity has been proposed as a stabilizer for oil-in-water emulsions. We ha...

The use of synthetic blended fibers to reduce cracking risk in high performance concrete.

DOT National Transportation Integrated Search

2014-09-01

Transportation departments have observed varying degrees of cracking in their concrete structures. Cracking of high performance reinforced concrete structures, in particular bridge decks, is of paramount concern to Pacific Northwest Departments of Tr...

Effects of interfacial interaction on the properties of poly(vinyl chloride)/styrene-butadiene rubber blends

NASA Astrophysics Data System (ADS)

Zhu, Shuihan

PVC/SBR blends---new thermoplastic elastomer material---were developed. They have potential applications due to low costs and low-temperature elasticity. A unique compatibilization method was employed to enhance the mechanical properties of the materials a compatibilizer miscible with one of the blend components can react chemically with the other component(s). Improvements in tensile and impact behavior were observed as a result of the compatibilization. A novel characterization technique to study the interface of PVC/SBR blends was developed. This technique involves the observation of the unstained sample under electron beam irradiation by a transmission electron microscope (TEM). An enrichment of rubber at the interface between PVC and SBR was detected in the compatiblized PVC/SBR blends. Magnetic relaxation measurements show that the rubber concentration in the proximity of PVC increases with the degree of covulcanization between NBR and SBR. The interface development and the rheological effect during processing were investigated. The interfacial concentration profile and the interfacial thickness were obtained by grayscale measurements on TEM micrographs, evaluation of SIMS images, and measurements of micromechanical properties.

Morphology Evolution of Polymer Blends under Intense Shear During High Speed Thin-Wall Injection Molding.

PubMed

Zhou, Yi; Yu, Feilong; Deng, Hua; Huang, Yajiang; Li, Guangxian; Fu, Qiang

2017-06-29

The morphology evolution under shear during different processing is indeed an important issue regarding the phase morphology control as well as final physical properties of immiscible polymer blends. High-speed thin wall injection molding (HSTWIM) has recently been demonstrated as an effective method to prepare alternating multilayered structure. To understand the formation mechanism better and explore possible phase morphology for different blends under HSTWIM, the relationship between the morphology evolution of polymer blends based on polypropylene (PP) under HSTWIM and some intrinsic properties of polymer blends, including viscosity ratio, interfacial tension, and melt elasticity, is systematically investigated in this study. Blends based on PP containing polyethylene (PE), ethylene vinyl alcohol copolymer (EVOH), and polylactic acid (PLA) are used as examples. Compatibilizer has also been added into respective blends to alter their interfacial interaction. It is demonstrated that dispersed phase can be deformed into a layered-like structure if interfacial tension, viscosity ratio, and melt elasticity are relatively small. While some of these values are relatively large, these dispersed droplets are not easily deformed under HSTWIM, forming ellipsoidal or fiber-like structure. The addition of a moderate amount of compatibilizer into these blends is shown to be able to reduce interfacial tension and the size of dispersed phase, thus, allowing more deformation on the dispersed phase. Such a study could provide some guidelines on phase morphology control of immiscible polymer blends under shear during various processing methods.

Tunable engineered skin mechanics via coaxial electrospun fiber core diameter.

PubMed

Blackstone, Britani Nicole; Drexler, Jason William; Powell, Heather Megan

2014-10-01

Autologous engineered skin (ES) offers promise as a treatment for massive full thickness burns. Unfortunately, ES is orders of magnitude weaker than normal human skin causing it to be difficult to apply surgically and subject to damage by mechanical shear in the early phases of engraftment. In addition, no manufacturing strategy has been developed to tune ES biomechanics to approximate the native biomechanics at different anatomic locations. To enhance and tune ES biomechanics, a coaxial (CoA) electrospun scaffold platform was developed from polycaprolactone (PCL, core) and gelatin (shell). The ability of the coaxial fiber core diameter to control both scaffold and tissue mechanics was investigated along with the ability of the gelatin shell to facilitate cell adhesion and skin development compared to pure gelatin, pure PCL, and a gelatin-PCL blended fiber scaffold. CoA ES exhibited increased cellular adhesion and metabolism versus PCL alone or gelatin-PCL blend and promoted the development of well stratified skin with a dense dermal layer and a differentiated epidermal layer. Biomechanics of the scaffold and ES scaled linearly with core diameter suggesting that this scaffold platform could be utilized to tailor ES mechanics for their intended grafting site and reduce graft damage in vitro and in vivo.

Fiber-reinforced silicone for tracheobronchial stents: An experimental study.

PubMed

Vearick, Samanta Bianchi; Demétrio, Kétner Bendo; Xavier, Rogério Gastal; Moreschi, Alexandre Heitor; Muller, André Frotta; Sanches, Paulo Roberto Stefani; Dos Santos, Luis Alberto Loureiro

2018-01-01

A trachea is a tubular structure composed of smooth muscle that is reinforced with cartilage rings. Some diseases can cause sagging in smooth muscle and cartilaginous tissue. The end result is reduction (narrowing) of the trachea diameter. A solution to this problem is the use of tracheal stents, which are small tubular devices made of silicone. One is inserted into the trachea to prevent or correct its constriction. The purpose of tracheal stent use is to maintain cartilage support that would otherwise be lost in the airway. Current tracheal stent models present limitations in terms of shape and characteristics of the silicone used in their production. One of the most important is the large thickness of the wall, which makes its placement difficult; this mainly applies to pediatric patients. The wall thickness of the stent is closely related to the mechanical properties of the material. This study aims to test the reinforcement of silicone with three kinds of fibers, and then stents that were produced using fiber with the best compressive strength characteristics. Silicone samples were reinforced with polypropylene (PP), polyamide (PA), and carbon fiber (CF) at concentrations of 2% and 4% (vol%), which then underwent tensile strength and Shore A hardness testing. Samples with fiber showed good characteristics; surface analyses were carried out and they were used to produce stents with an internal diameter of 11 or 13mm and a length of 50mm. Stents underwent compression tests for qualitative evaluation. Samples with 2% and 4% CF blends showed the best mechanical performance, and they were used to produce stents. These samples presented similar compressive strengths at low deformation, but stents with a 4% CF blend exhibited improved compressive strength at deformations greater than 30-50% of their diameter (P ≤ 0.05). The addition of 2% and 4% CF blends conferred greater mechanical strength and resistance to the silicone matrix. This is particularly true at low deformation, which is the condition where the stent is used when implanted. In the finite element compression strength tests, the stent composite showed greater compression strength with the addition of fiber, and the results were in accordance with mechanical compression tests performed on the stents. In vivo tests showed that, after 30 days of post-implantation in sheep trachea, an inflammatory process occurred in the region of the trachea in contact with the stent composite and with the stent without fiber (WF). This response is a common process during the first few days of implantation. Copyright © 2017 Elsevier Ltd. All rights reserved.

The development of a new corn fiber gum isolation process that preserves its functional components

USDA-ARS?s Scientific Manuscript database

Corn fiber gum (CFG) is a hemicellulose (arabinoxylan)-enriched fraction obtained by the extraction of corn bran/fiber using a mild alkaline hydrogen peroxide process. The unique polysaccharide, CFG, with its low solution viscosity has been proposed as a stabilizer for oil-in-water emulsions. We ha...

Subcellular fractionation on Percoll gradient of mossy fiber synaptosomes: morphological and biochemical characterization in control and degranulated rat hippocampus.

PubMed

Taupin, P; Zini, S; Cesselin, F; Ben-Ari, Y; Roisin, M P

1994-04-01

A method for preparation of hippocampal mossy fiber synaptosomes directly from the postnuclear pellet is presented. This method represents an adaptation of that previously described for the isolation of synaptosomes by centrifugation through Percoll gradients directly from the supernatant fraction. We have characterized by electron microscopy two fractions, PII and PIII, enriched in mossy fiber synaptosomes; fraction PIII had 75% mossy fiber synaptosomes with well-preserved morphology (large size 3 microns, complex morphology, high synaptic vesicle density, multisynapses), whereas fraction PII contained 12%. These fractions were enriched in lactate dehydrogenase activity indicating that the integrity of synaptosomes was preserved. Compared with the other synaptosomal fractions, these fractions showed greater levels of dynorphin A (1-8) immunoreactivity and endogenous zinc, which are particularly concentrated in hippocampal mossy fiber terminals. Furthermore, we prepared synaptosomes from adult hippocampus after neonatal irradiation, which destroys the majority of granule cells and associated mossy fibers. The levels of dynorphin and zinc decreased by 88 and 70% in fraction PII and by 95 and 90%, respectively, in PIII. These results suggest that the rapid Percoll procedure is convenient for the purification of mossy fiber synaptosomes.

Electrospun Blends of Gelatin and Gelatin-dendrimer Conjugates as a Wound Dressing and Drug Delivery Platform

PubMed Central

Dongargaonkar, Alpana A.; Bowlin, Gary L.; Yang, Hu

2013-01-01

In this work, we report a new nanofiber construct based on electrospun blends of gelatin and gelatin-dendrimer conjugates. Highly branched star-shaped polyamidoamine (PAMAM) dendrimer G3.5 was covalently conjugated to gelatin via EDC/NHS chemistry. Blends of gelatin and gelatin-dendrimer conjugates mixed with various loading levels of silver acetate (0, 0.83, 1.65, and 3.30% w/w) were successfully electrospun into nanofiber constructs (NCs). The NCs were further converted into semi-interpenetrating networks (sIPNs) with photoreactive polyethylene glycol diacrylate (Mn=575 gmol-1) (PEG DA575). They were characterized in terms of fiber morphology, diameter, pore size, permeability, degradation, and mechanical properties. The resulting sIPN NCs retained nanofiber morphology, possessed similar fiber diameters to counterpart NCs, and gained improved structural stability. The sIPN NCs also showed good swelling capacity owing to porous structures and were permeable to aqueous solutions. Silvercontaining sIPN NCs allowed sustained silver release and showed antimicrobial activity against two common types of pathogens—Staphylococcus aureus and Pseudomonas aeruginosa. Incorporation of dendrimers into the gelatin nanofibers through covalent conjugation not only expands drug loading capacity of nanofiber constructs but provides tremendous flexibility for developing multifunctional electrospun dressing materials. PMID:24127747

Wood Sawdust/Natural Rubber Ecocomposites Cross-Linked by Electron Beam Irradiation

PubMed Central

Manaila, Elena; Stelescu, Maria Daniela; Craciun, Gabriela; Ighigeanu, Daniel

2016-01-01

The obtaining and characterization of some polymeric eco-composites based on wood sawdust and natural rubber is presented. The natural rubber was cross-linked using the electron beam irradiation. The irradiation doses were of 75, 150, 300 and 600 kGy and the concentrations of wood sawdust were of 10 and 20 phr, respectively. As a result of wood sawdust adding, the physical and mechanical properties such as hardness, modulus at 100% elongation and tensile strength, showed significant improvements. The presence of wood sawdust fibers has a reinforcing effect on natural rubber, similar or better than of mineral fillers. An increase in the irradiation dose leads to the increasing of cross-link density, which is reflected in the improvement of hardness, modulus at 100% elongation and tensile strength of blends. The cross-linking rates, appreciated using the Flory-Rehner equation, have increased with the amount of wood sawdust in blends and with the irradiation dose. Even if the gel fraction values have varied irregularly with the amount of wood sawdust and irradiation dose it was over 90% for all blends, except for the samples without wood sawdust irradiated with 75 kGy. The water uptake increased with increasing of fiber content and decreased with the irradiation dose. PMID:28773626

Effect of moisture transport on microclimate under T-shirts.

PubMed

Dai, Xiao-Qun; Imamura, Ritsuko; Liu, Guo-Lian; Zhou, Fu-Ping

2008-09-01

Water transport through garments has influence on the microclimate between the garments and the body beneath; thus the thermal comfort feeling for the wearer. Soybean protein fiber (SPF), a new type environmental fiber, which has been reported to be superior in water transfer, is often blended with cotton to improve the water transport property. In this paper, T-shirts made of this SPF/cotton blended fabric were focused in comparison with T-shirts made of cotton fabric. Wicking and immersion tests were carried out on the two types of fabrics to investigate the water transport and absorption properties, respectively; wear trials of T-shirts made of the fabrics were also conducted. Comparing with the cotton fabric which had better water absorptive property, it was found that the blended fabric with superior wicking ability could not only delay the increase of the vapor pressure under the T-shirt at the beginning of the exercise, but also help to keep it lower through the exercise significantly, and also kept the skin temperature under the T-shirt lower. It was made clear that it is the water transfer property rather than the water absorption property helps to take away sweat quickly and prevents the increase of the humidity and temperature at skin surface, thus maintaining a comfort microclimate under garments.

Wood Sawdust/Natural Rubber Ecocomposites Cross-Linked by Electron Beam Irradiation.

PubMed

Manaila, Elena; Stelescu, Maria Daniela; Craciun, Gabriela; Ighigeanu, Daniel

2016-06-23

The obtaining and characterization of some polymeric eco-composites based on wood sawdust and natural rubber is presented. The natural rubber was cross-linked using the electron beam irradiation. The irradiation doses were of 75, 150, 300 and 600 kGy and the concentrations of wood sawdust were of 10 and 20 phr, respectively. As a result of wood sawdust adding, the physical and mechanical properties such as hardness, modulus at 100% elongation and tensile strength, showed significant improvements. The presence of wood sawdust fibers has a reinforcing effect on natural rubber, similar or better than of mineral fillers. An increase in the irradiation dose leads to the increasing of cross-link density, which is reflected in the improvement of hardness, modulus at 100% elongation and tensile strength of blends. The cross-linking rates, appreciated using the Flory-Rehner equation, have increased with the amount of wood sawdust in blends and with the irradiation dose. Even if the gel fraction values have varied irregularly with the amount of wood sawdust and irradiation dose it was over 90% for all blends, except for the samples without wood sawdust irradiated with 75 kGy. The water uptake increased with increasing of fiber content and decreased with the irradiation dose.

Value-added products from chicken feather fiber and protein

NASA Astrophysics Data System (ADS)

Fan, Xiuling

Worldwide poultry consumption has generated a huge amount of feather "waste" annually. Currently, the feather has a low value-being used for animal feed in the world. The quality of fibrous air filters depend on their main component, fibers. The main physical structure of chicken feathers is barbs which can be used directly as fibers. They have small diameter, which makes them a good choice for air filtration. The main chemical structure of chicken feathers is structural fibrous protein, keratin. Therefore, chicken feathers could potentially be used for protein fiber production. To obtain chicken feather fibers, barbs were stripped from the quills by a stripping device and separated with a blender. Some feather fibers were entangled with polyester staple fibers, and needlepunched to form a nonwoven fabric. Some feather fibers were blended with CelBond(TM) bi-component polyester as binder fibers, and pressed between two hot plates to produce thermobonded nonwovens. Whole chicken feathers were ground into powder and their keratin was reduced in water. The reduced keratin was salt precipitated, dried and dissolved in ionic liquid with/without bleach cotton. The reduced chicken feather keratin ionic liquid solutions were spun into regenerated fibers through dry-jet wet spinning. The needlepunched and thermobonded nonwovens were tested for filtration and other properties. With an increase of areal density and feather fiber composition, the air permeability of the needlepunched nonwovens decreased, and their filtration efficiency and pressure drop both increased. The case can be made that feather fibers gave fabrics better filtration at the same fabric weight, but at the expense of air permeability and pressure drop. The scrim and needlepunching process improved the filtration efficiency. Their strength depended on scrim. The hot-press process was very simple. The thermobonded nonwovens had very high air permeability. In them, there was also an inverse relation between air permeability and either pressure drop or filtration efficiency. From these kinds of nonwovens, it is realized that feather fibers' fineness and the tree/fan-like structure of the feather does not offer a high level of performance advantages over conventional fibers. The use of feather fiber in air filtration applications must rely primarily on a favorable cost and weight differential in favor of the feather fiber. Only after chicken feather keratin was reduced, could it dissolve well in ionic liquid. 100% chicken feather keratin did not produce high tenacity fibers. Reduced chicken feather keratin and cellulose produced blend fibers with mechanical properties close to silk, cotton, and polyester fibers. Chemically reforming crosslinks might improve mechanical properties and the stability of the fibers to water and make them suitable for most fibrous applications. From this, it can be proposed that using chicken feathers for fiber production may be a good way to add value to chicken feather "waste".

Physical properties of recycled PET non-woven fabrics for buildings

NASA Astrophysics Data System (ADS)

Üstün Çetin, S.; Tayyar, A. E.

2017-10-01

Recycled fibers have been commonly used in non-woven production technology for engineering applications such as textile engineering and civil engineering. Nonwovens including recycled fibers can be utilized in insulation, roofing and floor separation applications. In this study, physical performance properties such as drape, bending resistance, tensile strength, and breaking elongation values of non-woven fabrics consisting of v-PET (virgin) and r-PET (recycled) fibers in five different blend ratios are examined comparatively. The test results indicated that r-PET can be used in non-wovens for civil engineering applications such as insulation, roofing and floor separation fulfilling the acceptable quality level values.

Molecular-Level Computational Investigation of Mechanical Transverse Behavior of p-Phenylene Terephthalamide (PPTA) Fibers

DTIC Science & Technology

2013-01-01

fabricated today are based on polymer matrix composites containing Kevlarw KM2 reinforcements , the present work will deal with generic PPTA fibers . In...Multi-length scale enriched continuum-level material model for Kevlarw- fiber reinforced polymer-matrix composites”, Journal of Materials...mechanical transverse behavior of p-phenylene terephthalamide (PPTA) fibers Purpose – A series of all-atom molecular-level computational analyses is

Influence of the addition of soy product and wheat fiber on rheological, textural, and other quality characteristics of pizza.

PubMed

Glicerina, Virginia; Balestra, Federica; Capozzi, Francesco; Dalla Rosa, Marco; Romani, Santina

2017-11-17

The effect of partial replacement of wheat flour with soy paste and wheat fiber on rheological, textural, physicochemical, and organoleptic characteristics of an enriched pizza base (E) was investigated in comparison with those of a control pizza base (C). New ingredients (e.g., enriched cooked ham, whey cheese, and tomato sauce realized using food industry by-products) were also used in E pizza topping to further increase its nutritional properties. Enriched dough was developed first at a laboratory level. Large and small deformation, moisture, leavening activity, and metabolic heat were tested. On the final product, produced at the industrial level, textural, color, sensory, and nutritional analyses were performed. Preliminary rheological analysis was essential to evaluate the suitability of the new pizza to be processed at industrial level. Both pizza dough samples showed a solid elastic-like behavior; however, the addition of soy and fiber increased moisture content of E pizza, due to the water binding ability of soy protein and to the effect of fibers that also decreased E dough elasticity. No differences in extensibility between the two samples were observed, whereas significantly lower values of resistance to extension and dough force were shown in sample E. These differences were likely due to the presence of soy that interfere with gluten formation and to the dietary fibers that interact with water. Ingredients used in E pizza improved its nutritional quality increasing dietary fibers and protein, and decreasing saturated fatty acids and cholesterol content, which contributed to decrease energy value, in terms of kilocalorie reduction. In this work, the effects of using new ingredients (e.g., soy paste, wheat fiber) on the rheological, textural, physicochemical, nutritional, and organoleptic characteristics of an enriched pizza type were investigated both at laboratory and industrial levels. The new pizza provides a product that combines solid technological performances, in terms of rheological properties and dough elasticity, with improved and balanced nutritional quality, thanks also to the ingredients used in the topping. Results demonstrate the possibility of obtaining new pizza products characterized by nutritional and sensorial properties tailored for different group of consumers. © 2017 Wiley Periodicals, Inc.

Can blended learning and the flipped classroom improve student learning and satisfaction in Saudi Arabia?

PubMed Central

Sajid, Muhammad R.; Abothenain, Fayha; Salam, Yezan; AlJayar, Dina; Obeidat, Akef

2016-01-01

Objectives To evaluate student academic performance and perception towards blended learning and flipped classrooms in comparison to traditional teaching. Methods This study was conducted during the hematology block on year three students. Five lectures were delivered online only. Asynchronous discussion boards were created where students could interact with colleagues and instructors. A flipped classroom was introduced with application exercises. Summative assessment results were compared with previous year results as a historical control for statistical significance. Student feedback regarding their blended learning experience was collected. Results A total of 127 responses were obtained. Approximately 22.8% students felt all lectures should be delivered through didactic lecturing, while almost 35% felt that 20% of total lectures should be given online. Students expressed satisfaction with blended learning as a new and effective learning approach. The majority of students reported blended learning was helpful for exam preparation and concept clarification. However, a comparison of grades did not show a statistically significant increase in the academic performance of students taught via the blended learning method. Conclusions Learning experiences can be enriched by adopting a blended method of instruction at various stages of undergraduate and postgraduate education. Our results suggest that blended learning, a relatively new concept in Saudi Arabia, shows promising results with higher student satisfaction. Flipped classrooms replace passive lecturing with active student-centered learning that enhances critical thinking and application, including information retention.  PMID:27591930

Mechanical Property Evaluation of Palm/Glass Sandwiched Fiber Reinforced Polymer Composite in Comparison with few natural composites

NASA Astrophysics Data System (ADS)

Raja Dhas, J. Edwin; Pradeep, P.

2017-10-01

Natural fibers available plenty can be used as reinforcements in development of eco friendly polymer composites. The less utilized palm leaf stalk fibers sandwiched with artificial glass fibers was researched in this work to have a better reinforcement in preparing a green composite. The commercially available polyester resin blend with coconut shell filler in nano form was used as matrix to sandwich these composites. Naturally available Fibers of palm leaf stalk, coconut leaf stalk, raffia and oil palm were extracted and treated with potassium permanganate solution which enhances the properties. For experimentation four different plates were fabricated using these fibers adopting hand lay-up method. These sandwiched composite plates are further machined to obtain ASTM standards Specimens which are mechanically tested as per standards. Experimental results reveal that the alkali treated palm leaf stalk fiber based polymer composite shows appreciable results than the others. Hence the developed composite can be recommended for fabrication of automobile parts.

Simultaneous Delivery of Highly Diverse Bioactive Compounds from Blend Electrospun Fibers for Skin Wound Healing.

PubMed

Peh, Priscilla; Lim, Natalie Sheng Jie; Blocki, Anna; Chee, Stella Min Ling; Park, Heyjin Chris; Liao, Susan; Chan, Casey; Raghunath, Michael

2015-07-15

Blend emulsion electrospinning is widely perceived to destroy the bioactivity of proteins, and a blend emulsion of water-soluble and nonsoluble molecules is believed to be thermodynamically unstable to electrospin smoothly. Here we demonstrate a method to retain the bioactivity of disparate fragile biomolecules when electrospun. Using bovine serum albumin as a carrier protein; water-soluble vitamin C, fat soluble vitamin D3, steroid hormone hydrocortisone, peptide hormone insulin, thyroid hormone triiodothyronine (T3), and peptide epidermal growth factor (EGF) were simultaneously blend-spun into PLGA-collagen nanofibers. Upon release, vitamin C maintained the ability to facilitate Type I collagen secretion by fibroblasts, EGF stimulated skin fibroblast proliferation, and insulin potentiated adipogenic differentiation. Transgenic cell reporter assays confirmed the bioactivity of vitamin D3, T3, and hydrocortisone. These factors concertedly increased keratinocyte and fibroblast proliferation while maintaining keratinocyte basal state. This method presents an elegant solution to simultaneously deliver disparate bioactive biomolecules for wound healing applications.

Carbon nano fibers reinforced composites origami inspired mechanical metamaterials with passive and active properties

NASA Astrophysics Data System (ADS)

Kshad, Mohamed Ali E.; D'Hondt, Clement; Naguib, Hani E.

2017-10-01

Core panels used for compression or impact damping are designed to dissipate energy and to reduce the transferred force and energy. They are designed to have high strain and deformation with low density. The geometrical configuration of such cores plays a significant role in redistributing the applied forces to dampen the compression and impact energy. Origami structures are renowned for affording large macroscopic deformation which can be employed for force redistribution and energy damping. The material selection for the fabrication of origami structures affects the core capacity to withstand compression and impact loads. Polymers are characterized by their high compression and impact resistance; the drawback of polymers is the low stiffness and elastic moduli compared with metallic materials. This work is focused on the study of the effect of Carbon Nano Fibers (CNF) on the global mechanical properties of the origami panel cores made of polymeric blends. The base matrix materials used were Polylactic Acid (PLA) and Thermoplastic Polyurethane (TPU) blends, and the percentages of the PLA/TPU were 100/0, 20/80, 65/35, 50/50, 20/80, and 0/100 as a percentage of weight. The weight percentages of CNF added to the polymeric blends were 1%, 3%, and 5%. This paper deals with the fabrication process of the polymeric reinforced blends and the origami cores, in order to predict the best fabrication conditions. The dynamic scanning calorimetry and the dynamic mechanical analyzer were used to test the reinforced blended base material for thermomechanical and viscoelastic properties. The origami core samples were fabricated using per-molded geometrical features and then tested for compression and impact properties. The results of the study were compared with previous published results which showed that there is considerable enhancement in the mechanical properties of the origami cores compared with the pure blended polymeric origami cores. The active properties of the origami unit cell made of composite polymers containing a low percentage of CNF were also investigated in this study, in which the shape memory effect test conducted on the origami unit cell.

Packaging produced from natural fibers and mycelium: Optimizing biomass blends to meet performance specifications

USDA-ARS?s Scientific Manuscript database

Polystyrene is non-biodegradable and has environmental issues associated with its disposal. A replacement for polystyrene that is biodegradable, environmentally friendly, and has similar performance characteristics is of interest to many ecologically minded companies and consumers. This study utiliz...

Developing lignin-based bio-nanofibers by centrifugal spinning technique.

PubMed

Stojanovska, Elena; Kurtulus, Mustafa; Abdelgawad, Abdelrahman; Candan, Zeki; Kilic, Ali

2018-07-01

Lignin-based nanofibers were produced via centrifugal spinning from lignin-thermoplastic polyurethane polymer blends. The most suitable process parameters were chosen by optimization of the rotational speed, nozzle diameter and spinneret-to-collector distance using different blend ratios of the two polymers at different total polymer concentrations. The basic characteristics of polymer solutions were enlightened by their viscosity and surface tension. The morphology of the fibers produced was characterized by SEM, while their thermal properties by DSC and TG analysis. Multiply regression was used to determine the parameters that have higher impact on the fiber diameter. It was possible to obtain thermally stable lignin/polyurethane nanofibers with diameters below 500nm. From the aspect of spinnability, 1:1 lignin/TPU contents were shown to be more feasible. On the other side, the most suitable processing parameters were found to be angular velocity of 8500rpm for nozzles of 0.5mm diameter and working distance of 30cm. Copyright © 2018 Elsevier B.V. All rights reserved.

Preparation and physicochemical properties of whole-bean soymilk.

PubMed

Kuo, Hsin-Yu; Chen, Shih-Hsin; Yeh, An-I

2014-01-22

Whole-bean soymilk has been prepared by using media-milling. Some characteristics of media-milled soymilk have been determined and compared with filtered soymilk (similar to commercial ones) and whole-bean soymilk prepared by blending. There existed particles in the nano/submicrometer scale in both media-milled and filtered soymilk. The particles in blended soymilk were greater than 1 μm. Media-milled soymilk was the most stable among three samples, even after autoclaving. Solid recovery (98.44 ± 0.16%), viscosity (160.59 ± 4.26 cps), dietary fiber (22.68 ± 0.97% on dry basis), total polyphenol recovery (95.15 ± 7.09%), and isoflavone content (4.42 ± 0.03 mg/g dry solid) of media-milled samples were greater than those of filtered ones. Aglycones, the most bioactive form of isoflavone, in autoclaved media-milled soymilk were more than 2-fold those in autoclaved filtered soymilk. With almost no okara generated, the media-milled soymilk retained fiber in soybeans which would be beneficial to human health.

Contribution of lipids, phenolic acids, and protein rich components to emulsifying properties of corn fiber gum and acacia gum

USDA-ARS?s Scientific Manuscript database

Corn fiber gum (CFG) is an arabinoxylan enriched fraction obtained by the extraction of corn bran/fiber using a proprietary alkaline hydrogen peroxide process. When purified CFG prepared by this process was hydrolyzed with concentrated base (1.5 N methanolic KOH at 70 °C for one hour) considerable ...

Development of Poly(lactic acid)/Chitosan Fibers Loaded with Essential Oil for Antimicrobial Applications

PubMed Central

Liu, Yaowen; Wang, Shuyao; Zhang, Rong; Lan, Wenting; Qin, Wen

2017-01-01

Cinnamon essential oil (CEO) was successfully encapsulated into chitosan (CS) nanoparticles at different loading amounts (1%, 1.5%, 2%, and 2.5% v/v) using oil-in-water (o/w) emulsion and ionic-gelation methods. In order to form active packaging, poly(lactic acid) (PLA) was used to fabricate PLA/CS-CEO composite fibers using a simple electrospinning method. The shape, size, zeta potential, and encapsulation efficacy of the CS-CEO nanoparticles were investigated. The composition, morphology, and release behavior of the composite fibers were investigated. PLA/CS-CEO-1.5 showed good stability and favorable sustained release of CEO, resulting in improved antimicrobial activity compared to the other blends. The PLA/CS-CEO fibers showed high long-term inactivation rates against Escherichia coli and Staphylococcus aureus due to the sustained release of CEO, indicating that the developed PLA/CS-CEO fibers have great potential for active food packaging applications. PMID:28737719

Importance of consumer perceptions in fiber-enriched food products. A case study with sponge cakes.

PubMed

Tarrega, Amparo; Quiles, Amparo; Morell, Pere; Fiszman, Susana; Hernando, Isabel

2017-02-22

Sponge cakes enriched with fiber from different sources (maltodextrin, wheat, apple, blackcurrant and a mixture of potato and Plantago ovata) were studied. Profiling of the different cakes was carried out, first using a check-all-that-apply (CATA) question then evaluating the consumers' likings using a hedonic scale. The consumers also completed a nutrition knowledge (NK) questionnaire that was used to classify them according to their NK level. The instrumental texture of the cakes was evaluated by the texture profile analysis (TPA) method. The consumers' response was not linked to their NK level, but it mainly depended on the importance they gave to the cakes' distinctive sensory characteristics. In general, liking increased for samples considered easy to chew, spongy, soft and sweet, and decreased for samples perceived as tasteless, dry or having a fruity or an odd flavor. The sponge cakes containing maltodextrin or wheat fiber, which mostly resembled a conventional cake, were the most liked in general. Those containing the other three fibers were rejected by part of the consumers, for being tasteless in the case of potato plus Plantago ovata fiber, for being dry and doughy in the case of apple fiber and for having an odd flavor in the case of blackcurrant fiber.

Flame Retardant Fibers for Human Space Exploration - Past, Present, and Future

NASA Technical Reports Server (NTRS)

Orndoff, Evelyne

2017-01-01

The National Aeronautics and Space Administration (NASA) has led in the development of unique flame retardant fibers for human spaceflight since the beginning of the Apollo program. After the Apollo 1 fire which killed Command Pilot Virgil I 'Gus' Grissom, Senior Pilot Edward H. White II, and Pilot Roger B. Chaffee from cardiac arrest on January 27, 1967, the accident investigators found severe third degree burns and melted spacesuits on the astronauts bodies. NASA immediately initiated an extensive research program aimed at developing flame retardant and flame resistant fibers for the enriched oxygen atmosphere of the Apollo crew cabin. Fibers are flame retardant when they have been modified by chemical and thermal treatments. Fibers are flame resistant when they are made of inherently flame resistant materials (i.e. glass, ceramic, highly aromatic polymers). Immediately after this tragic accident, NASA funded extensive research in specifically developing flame retardant fibers and fabrics. The early developmental efforts for human spaceflight were for the outer layer of the Apollo spacesuit. It was imperative that non-flammable fabrics be used in a 100% oxygen environment. Owens-Corning thus developed the Beta fiber that was immediately used in the Apollo program and later in the Space Shuttle program. Aside from the urgent need for protective fabrics for the spacesuit, NASA also needed flame retardant fabrics for both clothing and equipment inside the spacecraft. From the mid-1960s to the early 1980's, NASA contracted with many companies to develop inherently flame retardant fibers and flame retardant finishes for existing fibers. Fluorocarbons and aromatic polyamides were the polymers of great interest for the development of new inherently flame retardant fibers for enriched oxygen environments. These enriched environments varied for different space programs. For example, the Apollo program requirements were for materials that would not support combustion in a 70%/30% oxygen/nitrogen environment at 6.3 pounds per square inch (psi). The Skylab program flammability requirements were set at 80%/20% oxygen/nitrogen ratios at 5 psi. While many fibers produced under several NASA contracts were never used, a few have become commercial products. The intent of this paper is to present the developmental history of some of these new or modified textile fibers. These developmental efforts are presented at various levels of details depending on the source of the historical records.

Synthesis of high performance ceramic fibers by chemical vapor deposition for advanced metallics reinforcing

NASA Technical Reports Server (NTRS)

Revankar, Vithal; Hlavacek, Vladimir

1991-01-01

The chemical vapor deposition (CVD) synthesis of fibers capable of effectively reinforcing intermetallic matrices at elevated temperatures which can be used for potential applications in high temperature composite materials is described. This process was used due to its advantage over other fiber synthesis processes. It is extremely important to produce these fibers with good reproducible and controlled growth rates. However, the complex interplay of mass and energy transfer, blended with the fluid dynamics makes this a formidable task. The design and development of CVD reactor assembly and system to synthesize TiB2, CrB, B4C, and TiC fibers was performed. Residual thermal analysis for estimating stresses arising form thermal expansion mismatch were determined. Various techniques to improve the mechanical properties were also performed. Various techniques for improving the fiber properties were elaborated. The crystal structure and its orientation for TiB2 fiber is discussed. An overall view of the CVD process to develop CrB2, TiB2, and other high performance ceramic fibers is presented.

Tunable Engineered Skin Mechanics via Coaxial Electrospun Fiber Core Diameter

PubMed Central

Blackstone, Britani Nicole; Drexler, Jason William

2014-01-01

Autologous engineered skin (ES) offers promise as a treatment for massive full thickness burns. Unfortunately, ES is orders of magnitude weaker than normal human skin causing it to be difficult to apply surgically and subject to damage by mechanical shear in the early phases of engraftment. In addition, no manufacturing strategy has been developed to tune ES biomechanics to approximate the native biomechanics at different anatomic locations. To enhance and tune ES biomechanics, a coaxial (CoA) electrospun scaffold platform was developed from polycaprolactone (PCL, core) and gelatin (shell). The ability of the coaxial fiber core diameter to control both scaffold and tissue mechanics was investigated along with the ability of the gelatin shell to facilitate cell adhesion and skin development compared to pure gelatin, pure PCL, and a gelatin-PCL blended fiber scaffold. CoA ES exhibited increased cellular adhesion and metabolism versus PCL alone or gelatin-PCL blend and promoted the development of well stratified skin with a dense dermal layer and a differentiated epidermal layer. Biomechanics of the scaffold and ES scaled linearly with core diameter suggesting that this scaffold platform could be utilized to tailor ES mechanics for their intended grafting site and reduce graft damage in vitro and in vivo. PMID:24712409

Subcellular fractionation on Percoll gradient of mossy fiber synaptosomes: evoked release of glutamate, GABA, aspartate and glutamate decarboxylase activity in control and degranulated rat hippocampus.

PubMed

Taupin, P; Ben-Ari, Y; Roisin, M P

1994-05-02

Using discontinuous density gradient centrifugation in isotonic Percoll sucrose, we have characterized two subcellular fractions (PII and PIII) enriched in mossy fiber synaptosomes and two others (SII and SIII) enriched in small synaptosomes. These synaptosomal fractions were compared with those obtained from adult hippocampus irradiated at neonatal stage to destroy granule cells and their mossy fibers. Synaptosomes were viable as judged by their ability to release aspartate, glutamate and GABA upon K+ depolarization. After irradiation, compared to the control values, the release of glutamate and GABA was decreased by 57 and 74% in the PIII fraction, but not in the other fractions and the content of glutamate, aspartate and GABA was also decreased in PIII fraction by 62, 44 and 52% respectively. These results suggest that mossy fiber (MF) synaptosomes contain and release glutamate and GABA. Measurement of the GABA synthesizing enzyme, glutamate decarboxylase, exhibited no significant difference after irradiation, suggesting that GABA is not synthesized by this enzyme in mossy fibers.

Laboratory ginning and blending impacts on cotton fiber micronaire measurements

USDA-ARS?s Scientific Manuscript database

Micronaire, a critical cotton quality parameter, is normally measured in a conditioned laboratory, but increasing interest has been shown in new technologies that can measure micronaire both in and outside of the laboratory. Near Infrared (NIR) technology has demonstrated its ability to measure cot...

Nutritional and physicochemical characteristics of dietary fiber enriched pasta.

PubMed

Tudorica, C M; Kuri, V; Brennan, C S

2002-01-16

The relationship between pasta texture and physicostructural characteristics was determined in relation to potential starch degradation and subsequent glucose release. Pastas with added soluble and insoluble dietary fiber ingredients were evaluated in relation to biochemical composition, cooking properties, and textural characteristics. Results show that both the type and amount of added fiber influence the overall quality of both raw and cooked pasta. Glucose release may be significantly reduced by the addition of soluble dietary fiber.

Electrospun PLA: PCL composites embedded with unmodified and 3-aminopropyltriethoxysilane (ASP) modified halloysite nanotubes (HNT)

NASA Astrophysics Data System (ADS)

Haroosh, Hazim J.; Dong, Yu; Chaudhary, Deeptangshu S.; Ingram, Gordon D.; Yusa, Shin-ichi

2013-02-01

Electrospinning is a simple and versatile fiber synthesis technique in which a high-voltage electric field is applied to a stream of polymer melt or polymer solution, resulting in the formation of continuous micro/nanofibers. Halloysite nanotubes (HNT) have been found to achieve improved structural and mechanical properties when embedded into various polymer matrices. This research work focuses on blending poly( ɛ-caprolactone) (PCL) (9 and 15 wt%/v) and poly(lactic acid) (PLA) (fixed at 8 wt%/v) solutions with HNT at two different concentrations 1 and 2 wt%/v. Both unmodified HNT and HNT modified with 3-aminopropyltriethoxysilane (ASP) were utilized in this study. Fiber properties have been shown to be strongly related to the solution viscosity and electrical conductivity. The addition of HNT increased the solution viscosity, thus resulting in the production of uniform fibers. For both PCL concentrations, the average fiber diameter increased with the increasing of HNT concentration. The average fiber diameters with HNT-ASP were reduced considerably in comparison to those with unmodified HNT when using 15 wt%/v PCL. Slightly better dispersion was obtained for PLA: PCL composites embedded with HNT-ASP compared to unmodified HNT. Furthermore, the addition of HNT-ASP to the polymeric blends resulted in a moderate decrease in the degree of crystallinity, as well as slight reductions of glass transition temperature of PCL, the crystallization temperature and melting temperature of PLA within composite materials. The infrared spectra of composites confirmed the successful embedding of HNT-ASP into PLA: PCL nanofibers relative to unmodified HNT due to the premodification using ASP to reduce the agglomeration behavior. This study provides a new material system that could be potentially used in drug delivery, and may facilitate good control of the drug release process.

Enrichment and Strengthening of Indian Biotechnology Industry along with Academic Interface

ERIC Educational Resources Information Center

Singh, Shalini

2014-01-01

For many years, humankind has been incorporating biosciences in different places--from agriculture to food and medicine. Today, the nomenclature of biology has been recoined as Biotechnology, a technological science with a perfect blend of sophisticated techniques, manuals and application of fast delivery equipment and vehicles. It encompasses…

76 FR 51358 - National Nuclear Security Administration Amended Record of Decision: Disposition of Surplus...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-18

...: Disposition of Surplus Highly Enriched Uranium Environmental Impact Statement AGENCY: National Nuclear... decision at that time. The Supplement Analysis analyzed the potential environmental impacts associated with... radioactive waste (LLW). The HEU EIS evaluated the potential environmental impacts of down- blending at up to...

Effect of varying Nd:YAG laser fiber tips on porcine dermal tissue

NASA Astrophysics Data System (ADS)

Pergadia, Vani R.; Vari, Sandor G.; Snyder, Wendy J.; Duffy, J. T.; Weiss, Andrew B.; Fishbein, Michael C.; Thomas, Reem; Shi, Wei-Qiang; Tausend, Kevin J.; Grundfest, Warren S.

1994-02-01

We evaluated the effect of the 600 micrometers bare (flat tip) and 600/100 micrometers conical tip fibers on porcine skin. We compared their effect in both the continuous-wave (cw) and pulsed (P) modes (20 ms ON/OFF) at 20 W to that of the electrocautery at 100 W in the pure and blend 3 modes. On 11 farmer pigs, 6 cuts were made for each parameter combination. The samples were processed for histological evaluation. The cutting depth, cutting width, and total thermal damage (carbonization, coagulation and denaturation) were recorded for each parameter combination. The results show that the 600/100 micrometers conical fiber provides deeper resective capabilities than the 600 micrometers bare and electrocautery. In addition, the 600/100 micrometers conical tip fiber allows for narrower cuts with significantly less thermal necrosis when compared to the 600 micrometers bare and electrocautery. The results indicate that there is an advantage to using the sculptured tip fiber for creating incisions when compared to the bare fiber and electrocautery.

Microstructural study of codeposited pentacene:perfluoropentacene grown on KCl by TEM techniques

NASA Astrophysics Data System (ADS)

Félix, Rocío; Breuer, Tobias; Witte, Gregor; Volz, Kerstin; Gries, Katharina I.

2017-08-01

Transmission electron microscopy techniques have been used as a research tool to derive information on structure and orientation of organic semiconductor blends. Within this work, we have studied the structure and morphology of pentacene (PEN, C22H14) and perfluoropentacene (PFP, C22F14) blends grown with [2:1] and [1:2] mixing ratios on KCl substrates. The [2:1] mixture exhibits a uniform layer on the substrate with domains that are rotated in-plane by 90° towards each other. Electron diffraction experiments revealed that these domains are formed by a crystalline mixed phase (consisting of PEN and PFP) and a PEN phase in excess whose lattice parameters are rather similar. By contrast, in the [1:2] blend, two different arrangements were found. The majority of the sample exhibits some spicular fibers on a background layer lying on top of the KCl substrate. The microstructural characterization revealed that these fibers consist of pure PFP in excess while the background layer is formed by the mixed phase. The other arrangement, which is present to a lesser extent, consists of a PFP film that is in direct contact with the KCl substrate. Using electron diffraction experiments, the orientation of the different phases with respect to each other and in some cases relative to the KCl substrate has been determined.

Gluten-free snacks using plantain-chickpea and maize blend: chemical composition, starch digestibility, and predicted glycemic index.

PubMed

Flores-Silva, Pamela C; Rodriguez-Ambriz, Sandra L; Bello-Pérez, Luis A

2015-05-01

An increase in celiac consumers has caused an increasing interest to develop good quality gluten-free food products with high nutritional value. Snack foods are consumed worldwide and have become a normal part of the eating habits of the celiac population making them a target to improve their nutritive value. Extrusion and deep-frying of unripe plantain, chickpea, and maize flours blends produced gluten-free snacks with high dietary fiber contents (13.7-18.2 g/100 g) and low predicted glycemic index (28 to 35). The gluten-free snacks presented lower fat content (12.7 to 13.6 g/100 g) than those reported in similar commercial snacks. The snack with the highest unripe plantain flour showed higher slowly digestible starch (11.6 and 13.4 g/100 g) than its counterpart with the highest chickpea flour level (6 g/100 g). The overall acceptability of the gluten-free snacks was similar to that chili-flavored commercial snack. It was possible to develop gluten-free snacks with high dietary fiber content and low predicted glycemic index with the blend of the 3 flours, and these gluten-free snacks may also be useful as an alternative to reduce excess weight and obesity problems in the general population and celiac community. © 2015 Institute of Food Technologists®

Detection of low levels of Listeria monocytogenes cells by using a fiber-optic immunosensor.

PubMed

Geng, Tao; Morgan, Mark T; Bhunia, Arun K

2004-10-01

Biosensor technology has a great potential to meet the need for sensitive and nearly real-time microbial detection from foods. An antibody-based fiber-optic biosensor to detect low levels of Listeria monocytogenes cells following an enrichment step was developed. The principle of the sensor is a sandwich immunoassay where a rabbit polyclonal antibody was first immobilized on polystyrene fiber waveguides through a biotin-streptavidin reaction to capture Listeria cells on the fiber. Capture of cells on the fibers was confirmed by scanning electron microscopy. A cyanine 5-labeled murine monoclonal antibody, C11E9, was used to generate a specific fluorescent signal, which was acquired by launching a 635-nm laser light from an Analyte 2000 and collected by a photodetector at 670 to 710 nm. This immunosensor was specific for L. monocytogenes and showed a significantly higher signal strength than for other Listeria species or other microorganisms, including Escherichia coli, Enterococcus faecalis, Salmonella enterica, Lactobacillus plantarum, Carnobacterium gallinarum, Hafnia alvei, Corynebacterium glutamicum, Enterobacter aerogenes, Pseudomonas aeruginosa, and Serratia marcescens, in pure or in mixed-culture setup. Fiber-optic results could be obtained within 2.5 h of sampling. The sensitivity threshold was about 4.3 x 10(3) CFU/ml for a pure culture of L. monocytogenes grown at 37 degrees C. When L. monocytogenes was mixed with lactic acid bacteria or grown at 10 degrees C with 3.5% NaCl, the detection threshold was 4.1 x 10(4) or 2.8 x 10(7) CFU/ml, respectively. In less than 24 h, this method could detect L. monocytogenes in hot dog or bologna naturally contaminated or artificially inoculated with 10 to 1,000 CFU/g after enrichment in buffered Listeria enrichment broth.

Isolation of low-molecular-weight proteins from amyloid plaque fibers in Alzheimer's disease.

PubMed

Selkoe, D J; Abraham, C R; Podlisny, M B; Duffy, L K

1986-06-01

During aging of the human brain, and particularly in Alzheimer's disease, progressive neuronal loss is accompanied by the formation of highly stable intra- and extraneuronal protein fibers. Using fluorescence-activated particle sorting, a method has been developed for purifying essentially to homogeneity the extracellular amyloid fibers that form the cores of senile plaques. The purified plaque cores each contain 60-130 pg of protein. Their amino acid composition shows abundant glycine, trace proline, and approximately 50% hydrophobic residues; it resembles that of enriched fractions of the paired helical filaments (PHF) that accumulate intraneuronally in Alzheimer's disease. Senile plaque amyloid fibers share with PHF insolubility in numerous protein denaturants and resistance to proteinases. However, treatment of either fiber preparation with concentrated (88%) formic acid or saturated (6.8 M) guanidine thiocyanate followed by sodium dodecyl sulfate causes disappearance of the fibers and releases proteins migrating at 5-7,000 and 11-15,000 Mr which appear to be dimerically related. Following their separation by size-exclusion HPLC, the proteins solubilized from plaque amyloid and PHF-enriched fractions have highly similar compositions and, on dialysis, readily aggregate into higher Mr polymers. Antibodies raised to the major low-Mr protein selectively label both plaque cores and vascular amyloid deposits in Alzheimer brain but do not stain neurofibrillary tangles, senile plaque neurites, or any other neuronal structure. Thus, extraneuronal amyloid plaque filaments in Alzheimer's disease are composed of hydrophobic low-Mr protein(s) which are also present in vascular amyloid deposits. Current evidence suggests that such protein(s) found in PHF-enriched fractions may derive from copurifying amyloid filaments rather than from PHF.

Preliminary Results on Luminaire Designs for Hybrid Solar Lighting Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Earl, D.D.

2001-06-15

We report on the design of two hybrid lighting luminaires that blend light from a fiber optic end-emitted solar source with electric T8 fluorescent lamps. Both designs involve the retrofit of a commercially-available recessed fluorescent luminaire with minimal reductions in the original luminaire's optical efficiency. Two methods for high-angle dispersion of fiber optic end-emitted solar light are described and the resulting spatial intensity distributions, simulated using ZEMAX, are compared with standard cylindrical fluorescent tubes. Differences in spatial intensity distribution are qualitatively characterized and potential design improvements discussed.

Production of bio-based fiber gums from the waste streams resulting from the commercial processing of corn bran and oat hulls

USDA-ARS?s Scientific Manuscript database

The U.S. food and non-food industries would benefit from the development of a domestically produced crude, semi-pure and pure bio-based fiber gum from corn bran and oat hulls processing waste streams. When corn bran and oat hulls are processed to produce a commercial cellulose enriched fiber gel, th...

Chain confinement, phase transitions, and lamellar structure in semicrystalline polymers, polymer blends and polymer nanocomposites

NASA Astrophysics Data System (ADS)

Chen, Huipeng

Recent studies suggest that there are three phase fractions in semicrystalline polymers, the crystalline, the mobile amorphous and the rigid amorphous phases. Due to the distinct properties of the rigid amorphous fraction, RAF, it has been investigated for more than twenty years. In this thesis, a general method using quasi-isothermal temperature-modulated differential scaning calorimetry, DSC, is provided for the first time to obtain the temperature dependent RAF and the other two fractions, crystalline fraction and mobile amorphous fraction, MAF. For poly(ethylene terephthalate), PET, our results show RAF was vitrified during quasi-isothermal cooling after crystallization had been completed and became totally devitrified during quasi-isothermal heating before the start of melting. Several years after people initially discovered the existence of RAF, another issue arose relating to the physical location of RAF and mobile amorphous fraction, MAF, within a lamellar stack model. Two very different models to describe the location of RAF were proposed. In the Heterogeneous Stack Model, HET, RAF is located outside the lamellar stacks. In the Homogeneous Stack Model, HSM, RAF was located inside the lamellar stacks. To determine the lamellar structure of semicrystalline polymers comprising three phase, a general method is given in this thesis by using a combination of the DSC and small angle X-ray scattering, SAXS techniques. It has been applied to Nylon 6, isotactic polystyrene, iPS, and PET. It was found for all of these materials, the HSM model is correct to describe the lamellar structure. In addition to the determination of lamellar structures, this method can also provide the exact fraction of MAF inside and outside lamellar stacks for binary polymer blends. For binary polymer blends, MAF, normally is located partially inside and partially outside the lamellar stacks. However, the quantification of the MAF inside and outside the lamellar stacks has now been provided and is applied to the iPS/atactic polystyrene, aPS, blends. The fractions of MAF inside and outside the lamellar stacks were quantified for the first time. For A/B binary polymer blends, it has been reported that if B is already crystalline, the crystalline fraction would serve as a restriction on the subsequent growth of the crystallizable partner A, while amorphous fraction could be diffused from the crystalline growth front of the crystallizing A component. Considering the effect of RAF on binary blends, a new concept is provided: like the crystals, the RAF of one polymer component may inhibit the growth of crystals of the other blend partner. The non-isothermal crystallization of PET/poly(lactic acid), PLA, blends were investigated and the results confirmed the new concept is correct: PET forms a large amount of RAF and inhibits crystal formation in PLA. Then, we broadened the concept of RAF and investigated the RAF in recent 'hot' materials, polymer nanocomposites. It was found the fraction of RAF greatly increased with a small amount of multi-wall carbon nanotubes, MWCNT, loading in PET electrospun, ES, fibers. A general model is given for polymer ES fibers with MWCNTs: the addition of MWCNTs causes polymer chains in the ES fibers to become more extended, (ie, more stretched), resulting in more confinement of PET chains and an increase in the RAF.

Gastrointestinal tolerance and plasma status of carotenoids, EPA and DHA with a fiber-enriched tube feed in hospitalized patients initiated on tube nutrition: Randomized controlled trial.

PubMed

Jakobsen, L H; Wirth, R; Smoliner, C; Klebach, M; Hofman, Z; Kondrup, J

2017-04-01

During the first days of tube feeding (TF) gastrointestinal (GI) complications are common and administration of sufficient nutrition is a challenge. Not all standard nutritionally complete formulas contain dietary fiber, fish oil or carotenoids, key dietary nutrients for health and wellbeing. The aim of this study was to investigate the effects of a fiber, fish oil and carotenoid enriched TF formula on diarrhea, constipation and nutrient bioavailability. A multi-center randomized, double-blind, controlled, parallel trial compared the effects of a dietary fiber, fish oil and carotenoid-enriched TF formula (test) with an isocaloric non-enriched formula (control) in 51 patients requiring initiation of TF. Incidence of diarrhea and constipation (based on stool frequency and consistency) was recorded daily. Plasma status of EPA, DHA and carotenoids was measured after 7 days. The incidence of diarrhea was lower in patients receiving the test formula compared with the control group (19% vs. 48%, p = 0.034). EPA and DHA status (% of total plasma phospholipids) was higher after 7 days in test compared with control group (EPA: p = 0.002, DHA: p = 0.082). Plasma carotenoid levels were higher after 7 days in the test group compared with control group (lutein: p = 0.024, α-carotene: p = 0.005, lycopene: p = 0.020, β-carotene: p = 0.054). This study suggests that the nutrient-enriched TF formula tested might have a positive effect on GI tolerance with less diarrhea incidence and significantly improved EPA, DHA and carotenoid plasma levels during the initiation of TF in hospitalized patients who are at risk of diarrhea and low nutrient status. This trial was registered at trialregister.nl; registration number 2924. Copyright © 2016. Published by Elsevier Ltd.

10 CFR Appendix D to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Clothes Dryers

Code of Federal Regulations, 2011 CFR

2011-01-01

... granite weave, which is a blended fabric of 50 percent cotton and 50 percent polyester and weighs within... 50 percent polyester fibers. (b) Cloth material that is 24 inches by 36 inches and has been hemmed to...

Evaluation of visible and near-infrared spectroscopy as a tool for assessing fiber fineness during mechanical preparation of dew-retted flax.

PubMed

Sharma, H S S; Reinard, N

2004-12-01

Flax fiber must be mechanically prepared to improve fineness and homogeneity of the sliver before chemical processing and wet-spinning. The changes in fiber characteristics are monitored by an airflow method, which is labor intensive and requires 90 minutes to process one sample. This investigation was carried out to develop robust visible and near-infrared calibrations that can be used as a rapid tool for quality assessment of input fibers and changes in fineness at the doubling (blending), first, second, third, and fourth drawing frames, and at the roving stage. The partial least squares (PLS) and principal component regression (PCR) methods were employed to generate models from different segments of the spectra (400-1100, 1100-1700, 1100-2498, 1700-2498, and 400-2498 nm) and a calibration set consisting of 462 samples obtained from the six processing stages. The calibrations were successfully validated with an independent set of 97 samples, and standard errors of prediction of 2.32 and 2.62 dtex were achieved with the best PLS (400-2498 nm) and PCR (1100-2498 nm) models, respectively. An optimized PLS model of the visible-near-infrared (vis-NIR) spectra explained 97% of the variation (R(2) = 0.97) in the sample set with a standard error of calibration (SEC) of 2.45 dtex and a standard error of cross-validation (SECV) of 2.51 dtex R(2) = 0.96). The mean error of the reference airflow method was 1.56 dtex, which is more accurate than the NIR calibration. The improvement in fiber fineness of the validation set obtained from the six production lines was predicted with an error range of -6.47 to +7.19 dtex for input fibers, -1.44 to +5.77 dtex for blended fibers at the doubling, and -4.72 to +3.59 dtex at the drawing frame stages. This level of precision is adequate for wet-spinners to monitor fiber fineness of input fibers and during the preparation of fibers. The advantage of visNIR spectroscopy is the potential capability of the technique to assess fineness and other important quality characteristics of a fiber sample simultaneously in less than 30 minutes; the disadvantages are the expensive instrumentation and the expertise required for operating the instrument compared to the reference method. These factors need to be considered by the industry before installing an off-line NIR system for predicting quality parameters of input materials and changes in fiber characteristics during mechanical processing.

Flexural analysis of palm fiber reinforced hybrid polymer matrix composite

NASA Astrophysics Data System (ADS)

Venkatachalam, G.; Gautham Shankar, A.; Raghav, Dasarath; Santhosh Kiran, R.; Mahesh, Bhargav; Kumar, Krishna

2015-07-01

Uncertainty in availability of fossil fuels in the future and global warming increased the need for more environment friendly materials. In this work, an attempt is made to fabricate a hybrid polymer matrix composite. The blend is a mixture of General Purpose Resin and Cashew Nut Shell Liquid, a natural resin extracted from cashew plant. Palm fiber, which has high strength, is used as reinforcement material. The fiber is treated with alkali (NaOH) solution to increase its strength and adhesiveness. Parametric study of flexure strength is carried out by varying alkali concentration, duration of alkali treatment and fiber volume. Taguchi L9 Orthogonal array is followed in the design of experiments procedure for simplification. With the help of ANOVA technique, regression equations are obtained which gives the level of influence of each parameter on the flexure strength of the composite.

Man-made vitreous fiber produced from incinerator ash using the thermal plasma technique and application as reinforcement in concrete.

PubMed

Yang, Sheng-Fu; Wang, To-Mai; Lee, Wen-Cheng; Sun, Kin-Seng; Tzeng, Chin-Ching

2010-10-15

This study proposes using thermal plasma technology to treat municipal solid waste incinerator ashes. A feasible fiberization method was developed and applied to produce man-made vitreous fiber (MMVF) from plasma vitrified slag. MMVF were obtained through directly blending the oxide melt stream with high velocity compressed air. The basic technological characteristics of MMVF, including morphology, diameter, shot content, length and chemical resistance, are described in this work. Laboratory experiments were conducted on the fiber-reinforced concrete. The effects of fibrous content on compressive strength and flexural strength are presented. The experimental results showed the proper additive of MMVF in concrete can enhance its mechanical properties. MMVF products produced from incinerator ashes treated with the thermal plasma technique have great potential for reinforcement in concrete. 2010 Elsevier B.V. All rights reserved.

Digital gene expression profiling of flax (Linum usitatissimum L.) stem peel identifies genes enriched in fiber-bearing phloem tissue.

PubMed

Guo, Yuan; Qiu, Caisheng; Long, Songhua; Chen, Ping; Hao, Dongmei; Preisner, Marta; Wang, Hui; Wang, Yufu

2017-08-30

To better understand the molecular mechanisms and gene expression characteristics associated with development of bast fiber cell within flax stem phloem, the gene expression profiling of flax stem peels and leaves were screened, using Illumina's Digital Gene Expression (DGE) analysis. Four DGE libraries (2 for stem peel and 2 for leaf), ranging from 6.7 to 9.2 million clean reads were obtained, which produced 7.0 million and 6.8 million mapped reads for flax stem peel and leave, respectively. By differential gene expression analysis, a total of 975 genes, of which 708 (73%) genes have protein-coding annotation, were identified as phloem enriched genes putatively involved in the processes of polysaccharide and cell wall metabolism. Differential expression genes (DEGs) was validated using quantitative RT-PCR, the expression pattern of all nine genes determined by qRT-PCR fitted in well with that obtained by sequencing analysis. Cluster and Gene Ontology (GO) analysis revealed that a large number of genes related to metabolic process, catalytic activity and binding category were expressed predominantly in the stem peels. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the phloem enriched genes suggested approximately 111 biological pathways. The large number of genes and pathways produced from DGE sequencing will expand our understanding of the complex molecular and cellular events in flax bast fiber development and provide a foundation for future studies on fiber development in other bast fiber crops. Copyright © 2017 Elsevier B.V. All rights reserved.

Biscuit-making potential of millet/pigeon pea flour blends.

PubMed

Eneche, E H

1999-01-01

Biscuits were produced from millet flour (MF) and pigeon pea flour (PPF) blends. The various ratios of MF to PPF used were 100:0, 75:25, 65:35, and 50:50. The biscuits were analyzed for their nutritional composition. They all contained high proportions of protein (7.5-15.2%), fat (17.1-18.1%) and digestible carbohydrate (60.2-66.5%). The moisture content was in the range 5.0 to 6.6%, ash 1.5-2.3% and crude fiber 0-0.1%. Sensory evaluation results indicated that all the biscuits had high sensory ratings for all the selected attributes evaluated. The recipe with the 65% MF/35% PPF blend resulted in the highest scores for flavor, texture and general acceptability. There was no significant difference (p > 0.05) between all the biscuits and the familiar Nasco short cake biscuit (reference) in flavor, color, texture and general acceptability.

Electrospinning polymer blends for biomimetic scaffolds for ACL tissue engineering

NASA Astrophysics Data System (ADS)

Garcia, Vanessa Lizeth

The anterior cruciate ligament (ACL) rupture is one of the most common knee injuries. Current ACL reconstructive strategies consist of using an autograft or an allograft to replace the ligament. However, limitations have led researchers to create tissue engineered grafts, known as scaffolds, through electrospinning. Scaffolds made of natural and synthetic polymer blends have the potential to promote cell adhesion while having strong mechanical properties. However, enzymes found in the knee are known to degrade tissues and affect the healing of intra-articular injuries. Results suggest that the natural polymers used in this study modify the thermal properties and tensile strength of the synthetic polymers when blended. Scanning electron microscopy display bead-free and enzyme biodegradability of the fibers. Raman spectroscopy confirms the presence of the natural and synthetic polymers in the scaffolds while, amino acid analysis present the types of amino acids and their concentrations found in the natural polymers.

On-line tritium production monitor

DOEpatents

Mihalczo, John T.

1993-01-01

A scintillation optical fiber system for the on-line monitoring of nuclear reactions in an event-by-event manner is described. In the measurement of tritium production one or more optical fibers are coated with enriched .sup.6 Li and connected to standard scintillation counter circuitry. A neutron generated .sup.6 Li(n )T reaction occurs in the coated surface of .sup.6 Li-coated fiber to produce energetic alpha and triton particles one of which enters the optical fiber and scintillates light through the fiber to the counting circuit. The coated optical fibers can be provided with position sensitivity by placing a mirror at the free end of the fibers or by using pulse counting circuits at both ends of the fibers.

On-line tritium production monitor

DOEpatents

Mihalczo, J.T.

1993-11-23

A scintillation optical fiber system for the on-line monitoring of nuclear reactions in an event-by-event manner is described. In the measurement of tritium production one or more optical fibers are coated with enriched {sup 6}Li and connected to standard scintillation counter circuitry. A neutron generated {sup 6}Li(n)T reaction occurs in the coated surface of {sup 6}Li-coated fiber to produce energetic alpha and triton particles one of which enters the optical fiber and scintillates light through the fiber to the counting circuit. The coated optical fibers can be provided with position sensitivity by placing a mirror at the free end of the fibers or by using pulse counting circuits at both ends of the fibers. 5 figures.

Towards Designing Cognitively-Enriched Project-Oriented Courses within a Blended Problem-Based Learning Context

ERIC Educational Resources Information Center

Tambouris, Efthimios; Zotou, Maria; Tarabanis, Konstantinos

2014-01-01

Traditional education seems to gradually and moderately make way for self-directed and student-centred learning strategies that will efficiently enable students to reach their full potentials and will sufficiently prepare them for their upcoming professional careers. Problem-Based Learning (PBL) is such a strategy, since it enables active…

Synthesis of structured lipid enriched with omega fatty acids and sn-2 palmitic acid by enzymatic esterification and its incorporation in powdered infant formula.

PubMed

Nagachinta, Supakana; Akoh, Casimir C

2013-05-08

Structured lipid (SL) enriched with arachidonic (ARA) and docosahexaenoic (DHA) acids was produced from tripalmitin using Lipozyme TL IM. The effects of acyl donors, that is, free fatty acids vs fatty acid ethyl esters, on the reactions were compared. The highest total incorporation of ARA and DHA was obtained when the reaction continued for 24 h, at a substrate mole ratio of 9, using free fatty acids as acyl donors (acidolysis). The SL prepared by a large-scale acidolysis reaction contained 17.69 ± 0.09% total ARA, 10.75 ± 0.15% total DHA, and 48.53 ± 1.40% sn-2 palmitic acid. SL thermograms exhibited multiple peaks indicating complexity of the triacylglycerol (TAG) distribution. RP-HPLC analysis of SL revealed nine of 26 TAG molecular species that were similar to those of human milk fat. Powdered infant formulas containing the SL were prepared by wet-mixing/spray-drying and dry-blending methods. Formula prepared with microencapsulated SL and the dry-blending method had better oxidative stability and color quality.

Nutritionally enriched 1,3-diacylglycerol-rich oil: Low calorie fat with hypolipidemic effects in rats.

PubMed

Prabhavathi Devi, B L A; Gangadhar, K N; Prasad, R B N; Sugasini, D; Rao, Y Poorna Chandra; Lokesh, B R

2018-05-15

An enzymatic process was developed for the preparation of a nutritionally enriched 1,3-diacylglycerol(DAG)-rich oil from a blend of refined sunflower and rice bran oils. The process involves hydrolysis of vegetable oil blend using Candida cylindracea followed by esterification with glycerol using Lipozyme RM1M. The resultant DAG-rich oil contains 84% of DAG (66% of 1,3-DAG, 18% of 1,2-DAG) and 16% of triacylglycerol (TAG) along with micro nutrients like γ-oryzanol, tocotrienols, tocopherols and phytosterols. Nutritional studies of the DAG-rich oil were conducted in Wistar rats and compared with sunflower oil (SFO). The calorific value of the DAG-rich oil was estimated to be 6.45 Kcals/g as against 9.25 Kcals/g for SFO. The serum and liver cholesterol and TAG levels in rats fed with 1,3-DAG-rich oil were found to be significantly reduced as compared to rats fed diet containing SFO. We conclude that 1,3-DAG-rich oil is a low calorie fat and exhibits hypolipidemic effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

Compact reaction cell for homogenizing and down-blending highly enriched uranium metal

DOEpatents

McLean, W. II; Miller, P.E.; Horton, J.A.

1995-05-02

The invention is a specialized reaction cell for converting uranium metal to uranium oxide. In a preferred form, the reaction cell comprises a reaction chamber with increasing diameter along its length (e.g. a cylindrical chamber having a diameter of about 2 inches in a lower portion and having a diameter of from about 4 to about 12 inches in an upper portion). Such dimensions are important to achieve the necessary conversion while at the same time affording criticality control and transportability of the cell and product. The reaction chamber further comprises an upper port and a lower port, the lower port allowing for the entry of reactant gases into the reaction chamber, the upper port allowing for the exit of gases from the reaction chamber. A diffuser plate is attached to the lower port of the reaction chamber and serves to shape the flow of gas into the reaction chamber. The reaction cell further comprises means for introducing gases into the reaction chamber and a heating means capable of heating the contents of the reaction chamber. The present invention also relates to a method for converting uranium metal to uranium oxide in the reaction cell of the present invention. The invention is useful for down-blending highly enriched uranium metal by the simultaneous conversion of highly enriched uranium metal and natural or depleted uranium metal to uranium oxide within the reaction cell. 4 figs.

Olive oil enriched in lycopene from tomato by-product through a co-milling process.

PubMed

Bendini, Alessandra; Di Lecce, Giuseppe; Valli, Enrico; Barbieri, Sara; Tesini, Federica; Toschi, Tullia Gallina

2015-01-01

The aim of this investigation was to produce an olive oil (OO) naturally enriched with antioxidants, recovering carotenoids, in particular lycopene, using an industrial by-product of tomato seeds and skin. For this purpose, a technological process in a low-scale industrial plant to co-mill olives and tomato by-product in de-frosted or freeze-dried forms was applied and studied with respect to control samples. Preliminary results obtained from two different experiments were carried out by 40 kg of cultivar Correggiolo olives and 60 kg of olive blends from different cultivars. In both the experiments, the co-milling showed significant enrichment in carotenoids, especially in lycopene (mean values of 5.4 and 7.2 mg/kg oil from defrosted and freeze-dried by-products, respectively). The experimental results demonstrated the possibility to obtain a new functional food naturally enriched in antioxidant compounds, which might be marketed as "OO dressing enriched in lycopene" or "condiment produced using olives and tomato by-product".

Postprandial lipid responses of butter blend containing fish oil in a single-meal study in humans.

PubMed

Overgaard, Julie; Porsgaard, Trine; Guo, Zheng; Lauritzen, Lotte; Mu, Huiling

2008-10-01

The postprandial effects of a butter product containing fish oil were investigated in a single-meal, randomized crossover study with a commercial butter product as the control. Twelve healthy males consumed two test meals with (13)C-labelled cholesterol (45 mg) and either an interesterified butter blend with fish oil (352 mg n-3 long-chain PUFA (LCPUFA)) or the commercial butter blend. Blood samples were collected after the meals and in the fasting condition on the test day and the following morning, and were analysed for cholesterol absorption, plasma lipid profile and fatty acid composition. No significant difference in the postprandial plasma fatty acid composition was observed between the groups, neither difference in cholesterol absorption, plasma cholesterol or the cholesterol contents of plasma lipoproteins. The incorporation of fish oil in the butter resulted in a significant lower concentration of triacylglycerols in the plasma 2 h after the meal in comparison with the commercial butter blend (p = 0.02); there was, however, no significant difference 24 h after the meal. In conclusion, fish oil-enriched butter blend provides a source to increase the intake of n-3 LCPUFA in the population, but has no acute effect on cholesterol absorption and plasma cholesterol concentration in human.

pH-responsive hydrogel coated fiber Bragg grating-based chemo mechanical sensor bioreactor applications

NASA Astrophysics Data System (ADS)

Kishore, P. V. N.; Sai Shankar, M.

2017-04-01

This paper describes a fiber optics based pH sensor by using wavelength modulated techniques. Fiber Bragg grating (FBG) is functionalized with a stimulus responsive hydrogel which induces a strain on FBG due to mechanical expansion of the gel in response to ambient pH changes. The gel is synthesized from the blends of Poly (vinyl alcohol)/Poly (acrylic acid). The induced strain results in a shift of FBG reflected peak which is monitored by an interrogator. The sensor system shows a good linearity in acidic pH range of 3 to 7 with a sensitivity of 12.16pm/pH. Besides that it shows good repeatability which proves it to be fit for pH sensing applications.

Hydrogel-coated fiber Bragg grating sensor for pH monitoring

NASA Astrophysics Data System (ADS)

Pabbisetti, Vayu Nandana Kishore; Madhuvarasu, Sai Shankar

2016-06-01

We present a fiber-optic wavelength-modulated sensor for pH applications. Fiber Bragg grating (FBG) is functionalized with a stimulus-responsive hydrogel that induces a strain on FBG due to mechanical expansion of the gel in response to ambient pH changes. The gel is synthesized from the blends of poly (vinyl alcohol)/poly (acrylic acid). The induced strain results in a shift of FBG reflected peak that is monitored by an interrogator. The sensor system shows good linearity in the acidic pH range of 3 to 7 with a sensitivity of 12.16 pm/pH. In addition, it shows good repeatability and oscillator behavior, which proves it to be fit for pH sensing applications.

Retention of natural antioxidants of blends of groundnut and sunflower oils with minor oils during storage and frying.

PubMed

Sunil, L; Reddy, P Vanitha; Krishna, A G Gopala; Urooj, Asna

2015-02-01

Unrefined groundnut oil (GNO) and refined sunflower oil (SFO) were blended with four minor oils including laboratory refined red palmolein (RRPO), physically refined rice bran oil (RBO), unrefined sesame oil (SESO), and unrefined coconut oil (CNO) containing natural antioxidants viz., β-carotene, tocopherols, oryzanol and lignans. The five blends prepared were GNO + RRPO (80:20), GNO + RBO (80:20), GNO + SESO (80:20), SFO + RRPO (50:50) and SFO + CNO (60:40). Prepared blends contained saturated fatty acids (SFA) (16.7-53.3 %); monounsaturated fatty acids (MUFA) (16.0-45.5 %) and polyunsaturated fatty acids (PUFA) (29.2-37.8 %). GNO blends viz., GNO + RRPO, GNO + RBO and GNO + SESO contained β-carotene (10.7 mg/100 g), oryzanol (0.12 g/100 g) and lignans (0.35 g/100 g) respectively as natural antioxidants. SFO was enriched with β-carotene (28.7 mg/100 g) and medium chain fatty acids (34.2 %) by blending with RRPO and CNO respectively. The oil blends (200 ml) were packed and stored at 38 °C/90 % relative humidity (RH) and 27 °C/65 % RH and samples were withdrawn at fixed intervals for analysis. Freshly prepared blends were also investigated for their frying performance. During storage, GNO + RBO blend showed highest oxidative stability probably due to the presence of oryzanol in the order GNO + RBO > GNO + SESO > GNO + RRPO. During frying, the peroxide value of GNO blends with RBO (rich in oryzanol) and SESO (rich in lignans) was less while the free fatty acid value was less in SFO blends with RRPO and CNO. Hence, blending of natural antioxidants rich minor oils (RRPO, RBO and SESO) with the major vegetable oils (GNO and SFO) may preserve them by lowering their rate of oxidation during storage and frying.

Vertical and lateral morphology effects on solar cell performance for a thiophene–quinoxaline copolymer:PC 70BM blend

DOE PAGES

Hansson, Rickard; Ericsson, Leif K. E.; Holmes, Natalie P.; ...

2015-02-13

The distribution of electron donor and acceptor in the active layer is known to strongly influence the electrical performance of polymer solar cells for most of the high performance polymer:fullerene systems. The formulation of the solution from which the active layer is spincoated plays an important role in the quest for morphology control. We have studied how the choice of solvent and the use of small amounts of a low vapour pressure additive in the coating solution influence the film morphology and the solar cell performance for blends of poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl] (TQ1) and [6,6]-phenyl C 71-butyric acid methyl ester (PC 70BM).more » We have investigated the lateral morphology using atomic force microscopy (AFM) and scanning transmission X-ray microscopy (STXM), the vertical morphology using dynamic secondary ion mass spectrometry (d-SIMS) and variable-angle spectroscopic ellipsometry (VASE), and the surface composition using near-edge X-ray absorption fine structure (NEXAFS). The lateral phase-separated domains observed in films spincoated from single solvents, increase in size with increasing solvent vapour pressure and decreasing PC 70BM solubility, but are not observed when 1-chloronaphthalene (CN) is added. A strongly TQ1-enriched surface layer is formed in all TQ1:PC 70BM blend films and rationalized by surface energy differences. The photocurrent and power conversion efficiency strongly increased upon the addition of CN, while the leakage current decreased by one to two orders of magnitude. The higher photocurrent correlates with the finer lateral structure and stronger TQ1-enrichment at the interface with the electron-collecting electrode. This indicates that the charge transport and collection are not hindered by this polymer-enriched surface layer. Neither the open-circuit voltage nor the series resistance of the devices are sensitive to the differences in morphology.« less

Plasma fatty acid changes following consumption of dietary oils containing n-3, n-6, and n-9 fatty acids at different proportions: preliminary findings of the Canola Oil Multicenter Intervention Trial (COMIT).

PubMed

Senanayake, Vijitha K; Pu, Shuaihua; Jenkins, David A; Lamarche, Benoît; Kris-Etherton, Penny M; West, Sheila G; Fleming, Jennifer A; Liu, Xiaoran; McCrea, Cindy E; Jones, Peter J

2014-04-23

The Canola Oil Multicenter Intervention Trial (COMIT) was a randomized controlled crossover study designed to evaluate the effects of five diets that provided different oils and/or oil blends on cardiovascular disease (CVD) risk factors in individuals with abdominal obesity. The present objective is to report preliminary findings on plasma fatty acid profiles in volunteers with abdominal obesity, following the consumption of diets enriched with n-3, n-6 and n-9 fatty acids. COMIT was conducted at three clinical sites, Winnipeg, Manitoba, Canada, Québec City, Québec, Canada and University Park, Pennsylvania, United States. Inclusion criteria were at least one of the followings: waist circumference (≥90 cm for males and ≥84 cm for females), and at least one other criterion: triglycerides ≥1.7 mmol/L, high density lipoprotein cholesterol <1 mmol/L (males) or <1.3 mmol/L (females), blood pressure ≥130 mmHg (systolic) and/or ≥85 mmHg (diastolic), and glucose ≥5.5 mmol/L. Weight-maintaining diets that included shakes with one of the dietary oil blends were provided during each of the five 30-day dietary phases. Dietary phases were separated by four-week washout periods. Treatment oils were canola oil, high oleic canola oil, high oleic canola oil enriched with docosahexaenoic acid (DHA), flax oil and safflower oil blend, and corn oil and safflower oil blend. A per protocol approach with a mixed model analysis was decided to be appropriate for data analysis. One hundred and seventy volunteers were randomized and 130 completed the study with a dropout rate of 23.5%. The mean plasma total DHA concentrations, which were analyzed among all participants as a measure of adherence, increased by more than 100% in the DHA-enriched phase, compared to other phases, demonstrating excellent dietary adherence. Recruitment and retention strategies were effective in achieving a sufficient number of participants who completed the study protocol to enable sufficient statistical power to resolve small differences in outcome measures. It is expected that the study will generate important data thereby enhancing our understanding of the effects of n-3, n-6, and n-9 fatty acid-containing oils on CVD risks. ClinicalTrials.gov NCT01351012.

Chemical composition, starch digestibility and antioxidant capacity of tortilla made with a blend of quality protein maize and black bean.

PubMed

Grajales-García, Eva M; Osorio-Díaz, Perla; Goñi, Isabel; Hervert-Hernández, Deisy; Guzmán-Maldonado, Salvador H; Bello-Pérez, Luis A

2012-01-01

Tortilla and beans are the basic components in the diet of people in the urban and rural areas of Mexico. Quality protein maize is suggested for tortilla preparation because it presents an increase in lysine and tryptophan levels. Beans contain important amounts of dietary fiber. The objective of this study was to prepare tortilla with bean and assesses the chemical composition, starch digestibility and antioxidant capacity using a quality protein maize variety. Tortilla with bean had higher protein, ash, dietary fiber and resistant starch content, and lower digestible starch than control tortilla. The hydrolysis rate (60 to 50%) and the predicted glycemic index (88 to 80) of tortilla decreased with the addition of bean in the blend. Extractable polyphenols and proanthocyanidins were higher in the tortilla with bean than control tortilla. This pattern produced higher antioxidant capacity of tortilla with bean (17.6 μmol Trolox eq/g) than control tortilla (7.8 μmol Trolox eq/g). The addition of bean to tortilla modified the starch digestibility and antioxidant characteristics of tortilla, obtaining a product with nutraceutical characteristics.

Nanofiber mats composed of a chitosan-poly(d,l-lactic-co-glycolic acid)-poly(ethylene oxide) blend as a postoperative anti-adhesion agent.

PubMed

Ko, Jae Eok; Ko, Young-Gwang; Kim, Won Il; Kwon, Oh Kyoung; Kwon, Oh Hyeong

2017-10-01

Postoperative tissue adhesion causes serious complications and suffering in 90% of patients after peritoneum surgery, while commercial anti-adhesion agents cannot completely prevent postoperative peritoneal adhesions. This study demonstrates electrospining of a blended solution of chitosan, poly(d,l-lactic-co-glycolic acid) (PLGA), and poly(ethylene oxide) (PEO) to fabricate a chitosan-based nanofibrous mat as a postoperative anti-adhesion agent. Rheological studies combined with scanning electron microscopy reveal that the spinnability of the chitosan-PLGA solution could be controlled by adjusting the blend ratio and concentration with average fiber diameter from 634 to 913 nm. Biodegradation of the nanofiber specimens showed accelerated hydrolysis by chitosan. Proliferation of fibroblasts and antimicrobial activity of nanofibers containing chitosan was analyzed. Abdominal defects with cecum adhesion in rats demonstrated that the blend nanofiber mats were effective in preventing tissue adhesion as a barrier (4 weeks after abdominal surgery) by coverage of exfoliated peritoneum and insufficient wound sites at the beginning of the wound healing process. Chitosan-PLGA-PEO blend nanofiber mats will provide a promising key as a postoperative anti-adhesion agent. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1906-1915, 2017. © 2016 Wiley Periodicals, Inc.

Oil sorption and retention capacities of thermally-bonded hybrid nonwovens prepared from cotton, kapok, milkweed and polypropylene fibers.

PubMed

Thilagavathi, G; Praba Karan, C; Das, Dipayan

2018-08-01

This work reports on a series of thermally-bonded, hybrid and oil-sorbent nonwovens developed from binary and tertiary mixing of cotton, kapok, and three varieties of milkweed fibers (Asclepias Syriaca, Calotropis Procera and Calotropis Gigantea) and polypropylene fibers. The physical and chemical properties of the fibers were investigated to examine their oleophilic character. It was observed that all the fiber surfaces were covered with natural wax. Further, kapok and milkweed fibers were found to have less cell wall thickness and high void ratio. Oil sorption and retention characteristics of these fibers were studied in loose fibrous form as well as in structured assembly form (thermally-bonded nonwovens) using high density oil and diesel oil. The effects of fiber diameter, fiber cross-sectional shape, fiber surface area and porosity on the oil sorption behavior were discussed. An excellent and a selective oil sorption behavior of milkweed fibers (Calotropis Procera and Calotropis Gigantea) blended with cotton and polypropylene fibers were observed. The maximum oil sorption capacity of the developed thermal bonded nonwoven was 40.16 g/g for high density (HD) oil and 23.00 g/g for diesel oil. Further, a high porosity combined with high surface area played a major role in deciding the oil sorption and retention characteristics. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of Bamboo Viscose on the Wicking and Moisture Management Properties of Gauze

NASA Astrophysics Data System (ADS)

Akbar, Abdul R.; Su, Siwei; Amjad, Bilal; Cai, Yingjie; Lin, Lina

2017-12-01

Bamboo viscose or regenerated cellulose fibers were used to check their absorbency properties effect on the wicking and moisture management in gauzes. Bamboo viscose and cotton fibers were spun into five different yarn samples with different fiber proportion by ring spinning. Fifteen different gauze samples were made of these yarn samples. The gauze samples were subjected to wicking test to check the wicking ability. Water vapor transmission test was applied to check the vapor transmission rate. These tests were applied to measure the effectiveness of bamboo viscose, cotton and blended gauze samples in wound healing. Pure bamboo gauzes and gauzes with high content of bamboo fiber, i.e. 75B:25C and 50B:50C, shows better wicking and vapor transmission properties. It makes gauzes with high bamboo viscose suitable for wound care applications because of moisture absorbency.

Sensory, Physico-Chemical and Water Sorption Properties of Corn Extrudates Enriched with Spirulina.

PubMed

Tańska, Małgorzata; Konopka, Iwona; Ruszkowska, Millena

2017-09-01

This study compares the quality of extrudates made from corn grits with the addition of up to 8% of spirulina powder. The sensory properties (shape, color, aroma, taste and crispness), chemicals (content of water, protein, fat, ash, fiber, carbohydrates, carotenoids, chlorophyll and phycocyanin) and physical properties (color, water absorption index, expansion indices, texture and water sorption properties) were determined. It has been found that spirulina-enriched extrudates had slightly lower sensory scores, but the addition of spirulina improved their nutritional value. The contents of protein, ash, fiber and β-carotene increased in extrudates with 8% of spirulina by 34, 36, 140 and 1,260%, respectively. The increasing addition of spirulina caused a decrease in extrudates lightness, an increase in their greenness and yellowness accompanied by a decrease of expansion indices and an increase of softness. Only small differences were found in water sorption properties, suggesting a similar behavior of spirulina-enriched extrudates during storage.

Elastin-PLGA hybrid electrospun nanofiber scaffolds for salivary epithelial cell self-organization and polarization.

PubMed

Foraida, Zahraa I; Kamaldinov, Tim; Nelson, Deirdre A; Larsen, Melinda; Castracane, James

2017-10-15

Development of electrospun nanofibers that mimic the structural, mechanical and biochemical properties of natural extracellular matrices (ECMs) is a promising approach for tissue regeneration. Electrospun fibers of synthetic polymers partially mimic the topography of the ECM, however, their high stiffness, poor hydrophilicity and lack of in vivo-like biochemical cues is not optimal for epithelial cell self-organization and function. In search of a biomimetic scaffold for salivary gland tissue regeneration, we investigated the potential of elastin, an ECM protein, to generate elastin hybrid nanofibers that have favorable physical and biochemical properties for regeneration of the salivary glands. Elastin was introduced to our previously developed poly-lactic-co-glycolic acid (PLGA) nanofiber scaffolds by two methods, blend electrospinning (EP-blend) and covalent conjugation (EP-covalent). Both methods for elastin incorporation into the nanofibers improved the wettability of the scaffolds while only blend electrospinning of elastin-PLGA nanofibers and not surface conjugation of elastin to PLGA fibers, conferred increased elasticity to the nanofibers measured by Young's modulus. After two days, only the blend electrospun nanofiber scaffolds facilitated epithelial cell self-organization into cell clusters, assessed with nuclear area and nearest neighbor distance measurements, leading to the apicobasal polarization of salivary gland epithelial cells after six days, which is vital for cell function. This study suggests that elastin electrospun nanofiber scaffolds have potential application in regenerative therapies for salivary glands and other epithelial organs. Regenerating the salivary glands by mimicking the extracellular matrix (ECM) is a promising approach for long term treatment of salivary gland damage. Despite their topographic similarity to the ECM, electrospun fibers of synthetic polymers lack the biochemical complexity, elasticity and hydrophilicity of the ECM. Elastin is an ECM protein abundant in the salivary glands and responsible for tissue elasticity. Although it's widely used for tissue regeneration of other organs, little is known about its utility in regenerating the salivary tissue. This study describes the use of elastin to improve the elasticity, hydrophilicity and biochemical complexity of synthetic nanofibers and its potential in directing in vivo-like organization of epithelial salivary cells which helps the design of efficient salivary gland regeneration scaffolds. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Stable optical soliton in the ring-cavity fiber system with carbon nanotube as saturable absorber

NASA Astrophysics Data System (ADS)

Li, Bang-Qing; Ma, Yu-Lan; Yang, Tie-Mei

2018-01-01

Main attention focuses on the theoretical study of the ring-cavity fiber laser system with carbon nanotubes (CNT) as saturable absorber (SA). The system is modelled as a non-standard Schrödinger equation with the coefficients blended real and imaginary numbers. New stable exact soliton solution is constructed by the bilinear transformation method for the system. The influences of the key parameters related to CNTs and SA on the optical pulse soliton are discussed in simulation. The soliton amplitude and phase can be tuned by choosing suitable parameters.

Renewable High-Performance Fibers from the Chemical Recycling of Cotton Waste Utilizing an Ionic Liquid.

PubMed

Asaadi, Shirin; Hummel, Michael; Hellsten, Sanna; Härkäsalmi, Tiina; Ma, Yibo; Michud, Anne; Sixta, Herbert

2016-11-23

A new chemical recycling method for waste cotton is presented that allows the production of virgin textile fibers of substantially higher quality than that from the mechanical recycling methods that are used currently. Cotton postconsumer textile wastes were solubilized fully in the cellulose-dissolving ionic liquid 1,5-diazabicyclo[4.3.0]non-5-enium acetate ([DBNH]OAc) to be processed into continuous filaments. As a result of the heterogeneous raw material that had a different molar mass distribution and degree of polymerization, pretreatment to adjust the cellulose degree of polymerization by acid hydrolysis, enzyme hydrolysis, or blending the waste cotton with birch prehydrolyzed kraft pulp was necessary to ensure spinnability. The physical properties of the spun fibers and the effect of the processing parameters on the ultrastructural changes of the fibers were measured. Fibers with a tenacity (tensile strength) of up to 58 cN tex -1 (870 MPa) were prepared, which exceeds that of native cotton and commercial man-made cellulosic fibers. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hybridized polymer matrix composites

NASA Technical Reports Server (NTRS)

House, E. E.; Hoggatt, J. T.; Symonds, W. A.

1980-01-01

The extent to which graphite fibers are released from resin matrix composites that are exposed to fire and impact conditions was determined. Laboratory simulations of those conditions that could exist in the event of an aircraft crash and burn situation were evaluated. The effectiveness of various hybridizing concepts in preventing this release of graphite fibers were also evaluated. The baseline (i.e., unhybridized) laminates examined were prepared from commercially available graphite/epoxy, graphite/polyimide, and graphite/phenolic materials. Hybridizing concepts investigated included resin fillers, laminate coatings, resin blending, and mechanical interlocking of the graphite reinforcement. The baseline and hybridized laminates' mechanical properties, before and after isothermal and humidity aging, were also compared. It was found that a small amount of graphite fiber was released from the graphite/epoxy laminates during the burn and impact conditions used in this program. However, the extent to which the fibers were released is not considered a severe enough problem to preclude the use of graphite reinforced composites in civil aircraft structure. It also was found that several hybrid concepts eliminated this fiber release. Isothermal and humidity aging did not appear to alter the fiber release tendencies.

Role of Thickness Confinement on Relaxations of the Fast Component in a Miscible A/B Blend

DOE Office of Scientific and Technical Information (OSTI.GOV)

Green, Peter; Sharma, Ravi P.; Dong, Ban Xuan

Spatial compositional heterogeneity strongly influences the dynamics of the A and B components of bulk miscible blends. Its effects are especially apparent in mixtures, such as poly(vinyl methyl ether) (PVME)/polystyrene (PS), where there exist significant disparities between the component glass transition temperatures (Tgs) and relaxation times. The relaxation processes characterized by distinct temperature dependencies and relaxation rates manifest different local compositional environments for temperatures above and below the glass transition temperature of the miscible blend. This same behavior is shown to exist in miscible PS/PVME films as thin as 100 nm. Moreover, in thin films, the characteristic segmental relaxation timesmore » t of the PVME component of miscible PVME/PS blends confined between aluminum (Al) substrates decrease with increasing molecular weight M of the PS component. These relaxation rates are film thickness dependent, in films up to a few hundred nanometers in thickness. This is in remarkable contrast to homopolymer films, where thickness confinement effects are apparent only on length scales on the order of nanometers. These surprisingly large length scales and M dependence are associated with the preferential interfacial enrichment - wetting layer formation - of the PVME component at the external Al interfaces, which alters the local spatial blend composition within the interior of the film. The implications are that the dynamics of miscible thin film blends are dictated in part by component Tg differences, disparities in component relaxation rates, component-substrate interactions, and chain lengths (entropy of mixing).« less

Effect of Dietary Fiber Enrichment and Different Cooking Methods on Quality of Chicken Nuggets.

PubMed

Pathera, Ashok K; Riar, C S; Yadav, Sanjay; Sharma, D P

2017-01-01

The effect of dietary fiber enrichment (wheat bran) and cooking methods (oven, steam and microwave) on functional and physico-chemical properties of raw nuggets formulation as well as nutritional, color and textural properties of chicken nuggets were analyzed in this study. Among different cooking methods used for nuggets preparation, steam cooked nuggets had significantly ( p <0.05) higher water holding capacity (56.65%), cooking yield (97.16%) and total dietary fiber content (4.32%) in comparison to oven and microwave cooked nuggets. The effect of cooking methods and wheat bran incorporation was also noticed on textural properties of the nuggets. Hardness, firmness and toughness values of oven and steam cooked nuggets were significantly ( p <0.05) higher than microwave cooked nuggets. Among nuggets prepared by different cooking methods, cohesiveness of microwave cooked nuggets was found to be significantly ( p <0.05) highest, whereas, oven cooked nuggets had significantly ( p <0.05) highest gumminess and chewiness values. Steam cooked nuggets were found to be better among all nuggets due to their higher cooking yield and dietary fiber content.

Effect of Dietary Fiber Enrichment and Different Cooking Methods on Quality of Chicken Nuggets

PubMed Central

Yadav, Sanjay; Sharma, D. P.

2017-01-01

The effect of dietary fiber enrichment (wheat bran) and cooking methods (oven, steam and microwave) on functional and physico-chemical properties of raw nuggets formulation as well as nutritional, color and textural properties of chicken nuggets were analyzed in this study. Among different cooking methods used for nuggets preparation, steam cooked nuggets had significantly (p<0.05) higher water holding capacity (56.65%), cooking yield (97.16%) and total dietary fiber content (4.32%) in comparison to oven and microwave cooked nuggets. The effect of cooking methods and wheat bran incorporation was also noticed on textural properties of the nuggets. Hardness, firmness and toughness values of oven and steam cooked nuggets were significantly (p<0.05) higher than microwave cooked nuggets. Among nuggets prepared by different cooking methods, cohesiveness of microwave cooked nuggets was found to be significantly (p<0.05) highest, whereas, oven cooked nuggets had significantly (p<0.05) highest gumminess and chewiness values. Steam cooked nuggets were found to be better among all nuggets due to their higher cooking yield and dietary fiber content. PMID:28747827

Developing a tissue-engineered neural-electrical relay using encapsulated neuronal constructs on conducting polymer fibers.

PubMed

Cullen, D Kacy; R Patel, Ankur; Doorish, John F; Smith, Douglas H; Pfister, Bryan J

2008-12-01

Neural-electrical interface platforms are being developed to extracellularly monitor neuronal population activity. Polyaniline-based electrically conducting polymer fibers are attractive substrates for sustained functional interfaces with neurons due to their flexibility, tailored geometry and controlled electro-conductive properties. In this study, we addressed the neurobiological considerations of utilizing small diameter (<400 microm) fibers consisting of a blend of electrically conductive polyaniline and polypropylene (PA-PP) as the backbone of encapsulated tissue-engineered neural-electrical relays. We devised new approaches to promote survival, adhesion and neurite outgrowth of primary dorsal root ganglion neurons on PA-PP fibers. We attained a greater than ten-fold increase in the density of viable neurons on fiber surfaces to approximately 700 neurons mm(-2) by manipulating surrounding surface charges to bias settling neuronal suspensions toward fibers coated with cell-adhesive ligands. This stark increase in neuronal density resulted in robust neuritic extension and network formation directly along the fibers. Additionally, we encapsulated these neuronal networks on PA-PP fibers using agarose to form a protective barrier while potentially facilitating network stability. Following encapsulation, the neuronal networks maintained integrity, high viability (>85%) and intimate adhesion to PA-PP fibers. These efforts accomplished key prerequisites for the establishment of functional electrical interfaces with neuronal populations using small diameter PA-PP fibers-specifically, improved neurocompatibility, high-density neuronal adhesion and neuritic network development directly on fiber surfaces.

IMPACT OF FOOD ENRICHED WITH DIETARY FIBER ON PATIENTS WITH CONSTIPATION PREDOMINANT IRRITABLE BOWEL SYNDROME.

PubMed

Sulaberidze, G; Okujava, M; Liluashvili, K; Tughushi, M; Abramashvili, M

2017-03-01

The causes of motility disorder of gastrointestinal tract and in particular Irritable Bowel Syndrome IBS are multifold, leading to complexity of treatment and requirement of more precise investigation of different pharmacological and non-pharmacological approaches. The aim of the study was investigation and comparison of the dietary fiber intake among women with constipation-predominant irritable bowel syndrome (IBS-C) and without, improvement of the dietary fiber intake using interventions with less rough changes of food related behavior and study of its effects on the bowel function, general wellbeing and compliance of patients. In total 100 healthy women, without any clinical signs of gastrointestinal disorders and 98 women who met Rome III criteria of IBS-C were enrolled in the dietary fiber intake assessment survey. The dietary habits of all participants, as well as bowel function, digestive feelings and general wellbeing of patients at baseline, on the 7th and 14th day of dietary intervention was assessed by the means of adopted questionnaires. The dietary supplementation was provided during the breakfast with fiber enriched food - bread and muesli. Research data reviled significantly lower daily intake of dietary fiber among patients with IBS-C compared with healthy group. The main source of dietary fiber in IBS-C group was bread and cereals, therefore introduction of dietary fiber rich bread and muesli in the breakfast didn't affect diet-related habits and determined high compliance of patients. Two week long intervention significantly improved the bowel function and irritation related complains, the feeling of general wellbeing was considerably better on the endpoint as well.

Osteoconductive properties of two different bioactive glass forms (powder and fiber) combined with collagen

NASA Astrophysics Data System (ADS)

Magri, Angela Maria Paiva; Fernandes, Kelly Rossetti; Ueno, Fabio Roberto; Kido, Hueliton Wilian; da Silva, Antonio Carlos; Braga, Francisco José Correa; Granito, Renata Neves; Gabbai-Armelin, Paulo Roberto; Rennó, Ana Claudia Muniz

2017-11-01

Bioactive Glasses (BG) is a group of synthetic silica-based materials with the unique ability to bond to living bone and can be used in bone repair. Although the osteogenic potential of BG, this material may have not present sufficient osteoconductive and osteoinductive properties to allow bone regeneration, especially in compromised situations. In order to overcome this limitation, it was proposed the combination the BG in two forms (powder and fiber) combined with collagen type I (COL-1). The aim of this study was to evaluate the BG/COL-based materials in terms of morphological characteristics, physicochemical features and mineralization. Additionally, the second objective was to investigate and compare the osteoconductive properties of two different bioactive glass forms (powder and fiber) enriched or not with collagen using a tibial bone defect model in rats. For this, four different formulations (BG powder - BGp, BG powder enriched with collagen - BGp/Col, BG fibers - BGf and BGp fibers enriched with collagen - BGf/Col) were developed. The physicochemical and morphological modifications were analyzed by SEM, FTIR, calcium assay and pH measurement. For in vivo evaluations, histopathology, morphometrical and immunohistochemistry were performed in a tibial defect in rats. The FTIR analysis indicated that BGp and BGf maintained the characteristic peaks for this class of material. Furthermore, the calcium assay showed an increased Ca uptake in the BG fibers. The pH measurements revealed that BGp (with or without collagen) presented higher pH values compared to BGf. In addition, the histological analysis demonstrated no inflammation for all groups at the site of the injury, besides a faster material degradation and higher bone ingrowth for groups with collagen. The immunohistochemistry analysis demonstrated Runx-2 and Rank-L expression for all the groups. Those findings support that BGp with collagen can be a promising alternative for treating fracture of difficult consolidation.

Synthesis, surface characterization, and biointeraction studies of low-surface energy side-chain polyetherurethanes

NASA Astrophysics Data System (ADS)

Porter, Stephen Christopher

1999-10-01

New segmented polyetherurethanes (PEUs) with low surface energy hydrocarbon and fluorocarbon side-chains attached to the polymer hard segments were synthesized. The surface chemistry of solvent cast polymer films was studied using X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry, and dynamic contact angle (DCA) measurements. Increases in the overall density and length of the alkyl side-chains within the PEUs resulted in greater side-chain concentrations at the polymer surface. PEUs bearing long alkyl (> C10 ) and perfluorocarbon side-chains were found to posses surfaces with highly enriched side-chain concentrations relative to the bulk polymer. In PEUs with significant side-chain surface enrichment, the relatively polar hard segment blocks were shown to reside in high concentrations just below the side-chain enriched surface layer. Furthermore, DCA measurements demonstrated that the surface of the alkyl side-chain PEUs did not undergo significant rearrangement when placed into an aqueous environment, whereas the surface of a hard segment model polymer bearing C18 sidechains (PEU-C18-HS) did. Hydrogen bonding within the PEUs was examined using FTIR and was shown to be disrupted by the addition of side-chains; an effect dependent on the density but not on the length of the side-chains. Heteropolymer blends comprised of mixtures of high side-chain density and side-chain free PEUs were compared with homopolymers having the same overall side-chain concentration as the blends. Significantly more surface enrichment of side-chains was found in the heteropolymer blends whereas hydrogen bonding nearly the same as in the homopolymers. Adsorption of native and delipidized human serum albumin (HSA) from pure solution and blood plasma; the elutabilty of adsorbed HSA; and static platelet adhesion to plasma preadsorbed surfaces, were all examined on alkyl side-chain PEUs. Several polymers with high C18 side-chain densities displayed increased affinity for albumin, and reduced elutability. Among these, PEU-C18-HS demonstrated a significant reduction in platelet adhesion at low plasma pre-adsorption concentrations. However, competitive binary adsorption of fibrinogen in the presence of HSA demonstrated lower relative albumin affinity for PEU-C18-HS than other PEUs. The observed effects are thought to be mainly a result of increased surface hydrophobicity of the alkyl-side chain modified PEU, and not high specificity albumin binding.

A microvolume molecularly imprinted polymer modified fiber-optic evanescent wave sensor for bisphenol A determination.

PubMed

Xiong, Yan; Ye, Zhongbin; Xu, Jing; Liu, Yucheng; Zhang, Hanyin

2014-04-01

A fiber-optic evanescent wave sensor for bisphenol A (BPA) determination based on a molecularly imprinted polymer (MIP)-modified fiber column was developed. MIP film immobilized with BPA was synthesized on the fiber column, and the sensor was then constructed by inserting the optical fiber prepared into a transparent capillary. A microchannel (about 2.0 μL) formed between the fiber and the capillary acted as a flow cell. BPA can be selectively adsorbed online by the MIP film and excited to produce fluorescence by the evanescent wave produced on the fiber core surface. The conditions for BPA enrichment, elution, and fluorescence detection are discussed in detail. The analytical measurements were made at 276 nm/306 nm (λ(ex)/λ(em)), and linearity of 3 × 10(-9)-5 × 10(-6) g mL(-1) BPA, a limit of detection of 1.7 × 10(-9) g mL(-1) BPA (3σ), and a relative standard deviation of 2.4% (n = 5) were obtained. The sensor selectivity and MIP binding measurement were also evaluated. The results indicated that the selectivity and sensitivity of the proposed fiber-optic sensor could be greatly improved by using MIP as a recognition and enrichment element. Further, by modification of the sensing and detection elements on the optical fiber, the proposed sensor showed the advantages of easy fabrication and low cost. The novel sensor configuration provided a platform for monitoring other species by simply changing the light source and sensing elements. The sensor presented has been successfully applied to determine BPA released from plastic products treated at different temperatures.

Postprandial lipid, glucose, insulin, and cholecystokinin responses in men fed barley pasta enriched with beta-glucan.

PubMed

Bourdon, I; Yokoyama, W; Davis, P; Hudson, C; Backus, R; Richter, D; Knuckles, B; Schneeman, B O

1999-01-01

Fiber regulates the rate and site of lipid and carbohydrate digestion and absorption and thus can modify the alimentary responses to a meal. When fiber sources containing viscous polysaccharides are included in a meal, a slower rate of carbohydrate and lipid absorption will modify the alimentary hormone and lipid responses. We investigated in 11 healthy men the response of insulin, glucose, cholecystokinin, and lipid to 2 test meals containing beta-glucan. One of the meals was high in fiber (15.7 g) and the other meal was low in fiber (5.0 g). The low-fiber meal contained pasta made with wheat flour. The high-fiber meals contained pasta prepared by replacing 40% of the wheat with 2 types of barley flour: barley naturally high in beta-glucan and the other a flour enriched in beta-glucan during processing. Plasma glucose and insulin concentrations increased significantly after all meals but the insulin response was more blunted after the barley-containing meals. The test meals were low in fat (25% of energy) but elicited an increase in plasma triacylglycerol and cholecystokinin. Cholecystokinin remained elevated for a longer time after the barley-containing meals. After the low-fiber meal, plasma cholesterol concentrations did not change significantly; however, 4 h after the barley-containing meals, the cholesterol concentration dropped below the fasting concentration and was significantly lower than that after the low-fiber meal. Carbohydrate was more slowly absorbed from the 2 high-fiber meals. Consumption of the barley-containing meals appeared to stimulate reverse cholesterol transport, which may contribute to the cholesterol-lowering ability of barley.

Deodorizing Properties of Photocatalyst Textiles and Its Effect Analysis

NASA Astrophysics Data System (ADS)

Zhang, Hongxia; Ge, Caihong; Zhu, Chengyan; Li, Yanqing; Tian, Wei; Cheng, Dongzhi; Pan, Zhongxiang

In this paper, yarns of photocatalyst modified polyester staple fiber, cotton and blended yarn of bamboo fiber and photocatalyst modified polyester were selected. Series of woven fabric were manufactured.The photocatalyst fiber contents of woven fabrics were changed from 0% to 100% with 20% gap, that is 0%,40%,60%,80% and 100%. The deodorant performance of these fabrics were tested and analyzed, it can be concluded that when the content of the photocatalyst is 80% or 100%, the fabrics owns better deodorant; when the photocatalyst content in fabric is 40% or 60%, it has the deodorantion properties but the effect was not good. It can be shown from this experimental study that the deodorizing fabrics can be considered to develop if only the content of photocatalyst is above the 80%.

Improved electrospinning processing of PU/PEDOT:PSS for electronic textile applications

NASA Astrophysics Data System (ADS)

Evke, Erin; Clippinger, Aaron; Spackman, Clayson; Samuel, Johnson; Ozisik, Rahmi

Poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate), PEDOT:PSS, is an electrically conductive polymer used in electronic textile (e-textile) applications, such as eletrochromic textiles, strain sensors, and resistive heaters. In the current study, PEDOT:PSS is blended with varying concentrations of polyurethane (PU) to investigate the flexibility of PU/PEDOT:PSS fibers that are produced via a modified electrospinning process where the jet is collected close to the tip of the needle, thereby, enabling the collection of straight fibers by a rotating spool. The electrical conductivity and mechanical properties of PU/PEDOT:PSS fibers are characterized to understand the effect of PU concentration and the processing parameters. This material is based upon work supported by the National Science Foundation under Grant No. CMMI-1538730.

Rapid oxidation/stabilization technique for carbon foams, carbon fibers and C/C composites

DOEpatents

Tan, Seng; Tan, Cher-Dip

2004-05-11

An enhanced method for the post processing, i.e. oxidation or stabilization, of carbon materials including, but not limited to, carbon foams, carbon fibers, dense carbon-carbon composites, carbon/ceramic and carbon/metal composites, which method requires relatively very short and more effective such processing steps. The introduction of an "oxygen spill over catalyst" into the carbon precursor by blending with the carbon starting material or exposure of the carbon precursor to such a material supplies required oxygen at the atomic level and permits oxidation/stabilization of carbon materials in a fraction of the time and with a fraction of the energy normally required to accomplish such carbon processing steps. Carbon based foams, solids, composites and fiber products made utilizing this method are also described.

Thermal/acoustical aircraft insulation material

NASA Technical Reports Server (NTRS)

Struzik, E. A.; Kunz, R.; Lin, R.

1975-01-01

Attempts made to improve the acoustical properties of low density Fiberfrax foam, an aircraft insulation material, are reported. Characterizations were also made of the physical and thermal properties. Two methods, optimization of fiber blend composition and modification of the foam fabrication process, were examined as possible means of improving foam acoustics. Flame impingement tests were also made; results show performance was satisfactory.

Durability of selected mulches, their ability to control weeds, and influence growth of loblolly pine seedlings

Treesearch

James D. Haywood

1999-01-01

Several mulc hes of natural, synthetic, or blends of natural and synthetic fibers were tested around newly planted loblolly pine (Pinus taeda L.) seedlings on a sheared and windrowed site in central Louisiana, U.S.A. The vegetation was primarily winter annuals, some residual grasses and forbs, and...

Advances and challenges of wood polymer composites

Treesearch

Roger M. Rowell

2006-01-01

Wood flour and fiber have been blended with thermoplastic such as polyethylene, polypropylene, polylactic acid and polyvinyl chloride to form wood plastic composites (WPC). WPCs have seen a large growth in the United States in recent years mainly in the residential decking market with the removal of CCA treated wood decking from residential markets. While there are...

Hot water extracted wood fiber for production of wood plastic composites (WPCs)

Treesearch

Manuel Raul Pelaez-Samaniego; Vikram Yadama; Eini Lowell; Thomas E. Amidon; Timothy L. Chaffee

2013-01-01

Undebarked ponderosa pine chips were treated by hot water extraction to modify the chemical composition. In the treated pine (TP) , the mass was reduced by approximately 20%, and the extract was composed mainly of degradation products of hemicelluloses. Wood flour produced from TP and unextracted chips (untreated pine, UP) was blended with high-density polyethylene (...

The reaction of boric acid with wood in a polystyrene matrix

Treesearch

Yanxin Wang; John Simonsen; Carlos Pascoal Neto; Joao Rocha; Timothy G. Rials; Eric Hart

1996-01-01

The reaction of boric acid with wood fibers in a polymer melt was examined using 13C-nuclear magnetic resonance (NMR), 11B-NMR. differential scanning calorimetry, dynamic mechanical analysis, and component extraction and by the determination of material properties. Samples were blended at 350 and 380°F in a roll mill. The...

Expansion and functional properties of extruded snacks enriched with nutrition sources from food processing by-products.

PubMed

Korkerd, Sopida; Wanlapa, Sorada; Puttanlek, Chureerat; Uttapap, Dudsadee; Rungsardthong, Vilai

2016-01-01

Rich sources of protein and dietary fiber from food processing by-products, defatted soybean meal, germinated brown rice meal, and mango peel fiber, were added to corn grit at 20 % (w/w) to produce fortified extruded snacks. Increase of total dietary fiber from 4.82 % (wb) to 5.92-17.80 % (wb) and protein from 5.03 % (wb) to 5.46-13.34 % were observed. The product indicated high expansion and good acceptance tested by sensory panels. There were 22.33-33.53 and 5.30-11.53 fold increase in the phenolics and antioxidant activity in the enriched snack products. The effects of feed moisture content, screw speed, and barrel temperature on expansion and nutritional properties of the extruded products were investigated by using response surface methodology. Regression equations describing the effect of each variable on the product responses were obtained. The snacks extruded with feed moisture 13-15 % (wb) and extrusion temperature at 160-180 °C indicated the products with high preference in terms of expansion ratio between insoluble dietary fiber and soluble dietary fiber balance. The results showed that the by-products could be successfully used for nutritional supplemented expanded snacks.

Combustion characteristics and retention-emission of selenium during co-firing of torrefied biomass and its blends with high ash coal.

PubMed

Ullah, Habib; Liu, Guijian; Yousaf, Balal; Ali, Muhammad Ubaid; Abbas, Qumber; Zhou, Chuncai

2017-12-01

The combustion characteristics, kinetic analysis and selenium retention-emission behavior during co-combustion of high ash coal (HAC) with pine wood (PW) biomass and torrefied pine wood (TPW) were investigated through a combination of thermogravimetric analysis (TGA) and laboratory-based circulating fluidized bed combustion experiment. Improved ignition behavior and thermal reactivity of HAC were observed through the addition of a suitable proportion of biomass and torrefied. During combustion of blends, higher values of relative enrichment factors in fly ash revealed the maximum content of condensing volatile selenium on fly ash particles, and depleted level in bottom ash. Selenium emission in blends decreased by the increasing ratio of both PW and TPW. Higher reductions in the total Se volatilization were found for HAC/TPW than individual HAC sample, recommending that TPW have the best potential of selenium retention. The interaction amongst selenium and fly ash particles may cause the retention of selenium. Copyright © 2017 Elsevier Ltd. All rights reserved.

A novel basalt fiber-reinforced polylactic acid composite for hard tissue repair.

PubMed

Chen, Xi; Li, Yan; Gu, Ning

2010-08-01

A basalt fiber (BF) was, for the first time, introduced into a poly(l-lactic acid) (PLLA) matrix as innovative reinforcement to fabricate composite materials for hard tissue repair. Firstly, BF/PLLA composites and pure PLLA were produced by the methods of solution blending and freeze drying. The results showed that basalt fibers can be uniformly dispersed in the PLLA matrix and significantly improve the mechanical properties and hydrophilicity of the PLLA matrix. The presence of basalt fibers may retard the polymer degradation rate and neutralize the acid degradation from PLLA. Osteoblasts were cultured in vitro to evaluate the cytocompatibility of the composite. An MTT assay revealed that osteoblasts proliferated well for 7 days and there was little difference found in their viability on both PLLA and BF/PLLA films, which was consistent with the alkaline phosphatase (ALP) activity results. A fluorescent staining observation showed that osteoblasts grew well on the composites. SEM images displayed that osteoblasts tended to grow along the fiber axis. The formation of mineralized nodules was observed on the films by Alizarin red S staining. These results suggest that the presence of basalt fibers does not noticeably affect osteoblastic behavior and the designed composites are osteoblast compatible. It is concluded that basalt fibers, as reinforcing fibers, may have promising applications in hard tissue repair.

Wet-milling transgenic maize seed for fraction enrichment of recombinant subunit vaccine.

PubMed

Moeller, Lorena; Taylor-Vokes, Raye; Fox, Steve; Gan, Qinglei; Johnson, Lawrence; Wang, Kan

2010-01-01

The production of recombinant proteins in plants continues to be of great interest for prospective large-scale manufacturing of industrial enzymes, nutrition products, and vaccines. This work describes fractionation by wet-milling of transgenic maize expressing the B subunit of the heat-labile enterotoxin of Escherichia coli (LT-B), a potent immunogen and candidate for oral vaccine and vaccine components. The LT-B gene was directed to express in seed by an endosperm specific promoter. Two steeping treatments, traditional steeping (TS, 0.2% SO(2) + 0.5% lactic acid) and water steeping (WS, water only), were evaluated to determine effects on recovery of functional LT-B in wet-milled fractions. The overall recovery of the LT-B protein from WS treatment was 1.5-fold greater than that from TS treatment. In both steeping types, LT-B was distributed similarly among the fractions, resulting in enrichment of functional LT-B in fine fiber, coarse fiber and pericarp fractions by concentration factors of 1.5 to 8 relative to the whole kernels on a per-mass basis. Combined with endosperm-specific expression and secretory pathway targeting, wet-milling enables enrichment of high-value recombinant proteins in low-value fractions, such as the fine fiber, and co-utilization of remaining fractions in alternative industrial applications.

Effect of four types of dietary fiber on the technological quality of pasta.

PubMed

Bustos, M C; Pérez, G T; León, A E

2011-06-01

The development of dietary fiber-enriched foods permits to obtain products with functional properties but can cause several problems in technological quality. The aim of this study was to study the quality of pasta obtained by replacing bread wheat flour with resistant starch II (RSII), resistant starch IV (RSIV), oat bran (OB) and inulin (IN) with the purpose of improving their nutritional quality. RSII, RSIV, OB and IN were substituted for a portion of bread wheat flour at levels 2.5%, 5.0%, 7.5% and 10.0%. Cooking properties, amylose and inulin losses, color and texture were measured. Finally, nutritional quality of enriched pasta was evaluated by protein losses during cooking and total dietary fiber. Microstructure of pasta was analyzed by scanning electron microscopy. Addition of RSII into pasta formulation improved the quality of the final product. RSIV-enriched pasta presented an improvement in textural characteristics and OB affected cooking properties positively up to 5% of substitution. Inulin was lost during cooking; besides, its addition negatively affected the technological quality of pasta. The results obtained in this study prove that it is possible to elaborate pasta with acceptable cooking quality and with improved nutritional characteristics by adding 10% of RSII and RSIV and 5% of OB.

Electrospinning of ceramic nanofibers

NASA Astrophysics Data System (ADS)

Eick, Benjamin M.

Silicon Carbide (SiC) nanofibers of diameters as low as 20 nm are fabricated. The fibers were produced through the electrostatic spinning of the preceramic poly(carbomethylsilane) with pyrolysis to ceramic. A new technique was used where the preceramic was blended with polystyrene (PS) and, subsequent to electrospinning, was exposed to UV to crosslink the PS and prevent fibers flowing during pyrolysis. Electrospun SiC fibers were characterized by FTIR, TGA-DTA, SEM, TEM, XRD, and SAED. Fibers were shown to be polycrystalline and nanograined with alpha-SiC 15R polytype being dominant, where commercial fiber production methods form beta-SiC 3C. Pyrolysis of the bulk polymer blend to SiC produced alpha-SiC 15R as the dominant polytype with larger grains showing that electrospinning nanofibers affects resultant crystallinity. Fibers produced were shown to have a core-shell structure of an oxide scale that was variable by pyrolysis conditions. Metal oxide powders (chromium oxide, cobalt oxide, iron oxide, silicon oxide, tantalum oxide, titanium oxide, tungsten oxide, vanadium oxide, and zirconium oxide), were converted to metal carbide powders and metal nitride powders by the process of carbothermal reduction (CTR). Synthetic pitch was explored as an alternative to graphite which is a common carbon source for CTR. It was shown via characterization with XRD that pitch performs as well and in some cases better than graphite and is therefore a viable alternative in CTR. Conversion of metal oxide powders with pitch led to conversion of sol-gel based metal oxide nanofibers produced by electrospinning. Pitch was soluble in the solutions xv that were electrospun allowing for intimate contact between the sol-gel and the carbon source for CTR. This method became a two step processing method to produce metal carbide and nitride nanofibers: first electrospin sol-gel based metal oxide nanofibers and subsequently pyrolize them in the manner of CTR to transform them. Results indicate that this method was capable of transforming hafnium, niobium, tantalum, titanium, vanadium, and zirconium sol-gel nanofibers to metal carbides and nitrides.

Preparation and electrochemical characterization of polymer electrolytes based on electrospun poly(vinylidene fluoride- co-hexafluoropropylene)/polyacrylonitrile blend/composite membranes for lithium batteries

NASA Astrophysics Data System (ADS)

Raghavan, Prasanth; Zhao, Xiaohui; Shin, Chorong; Baek, Dong-Ho; Choi, Jae-Won; Manuel, James; Heo, Min-Yeong; Ahn, Jou-Hyeon; Nah, Changwoon

Apart from PEO based solid polymer electrolytes, tailor-made gel polymer electrolytes based on blend/composite membranes of poly(vinylidene fluoride- co-hexafluoropropylene) and polyacrylonitrile are prepared by electrospinning using 14 wt% polymer solution in dimethylformamide. The membranes show uniform morphology with an average fiber diameter of 320-490 nm, high porosity and electrolyte uptake. Polymer electrolytes are prepared by soaking the electrospun membranes in 1 M lithium hexafluorophosphate in ethylene carbonate/dimethyl carbonate. Temperature dependent ionic conductivity and their electrochemical performance are studied. The blend/composite polymer electrolytes show good ionic conductivity in the range of 10 -3 S cm -1 at ambient temperature and good electrochemical performance. All the Polymer electrolytes show an anodic stability >4.6 V with stable interfacial resistance with storage time. The prototype cell shows good charge-discharge properties and stable cycle performance with comparable capacity fade compared to liquid electrolyte under the test conditions.

The spinoglenoid ligament. Anatomy, morphology, and histological findings.

PubMed

Plancher, Kevin D; Peterson, Robert K; Johnston, Jack C; Luke, Timothy A

2005-02-01

Dysfunction of the distal branch of the suprascapular nerve has been reported in athletes involved in throwing or overhead sports. The consistent presence of a dynamic anatomic structure, the spinoglenoid ligament, overlying the nerve in the spinoglenoid notch may be a contributing factor to the dysfunction of this nerve. The purpose of this study was to report the anatomy, morphology, and histological characteristics of the spinoglenoid ligament. The spinoglenoid ligaments of fifty-eight fresh-frozen cadaver shoulders were dissected to evaluate their anatomic dimensions, histological characteristics, and relationship to the suprascapular nerve, the posterior part of the capsule, and the glenoid rim. The spinoglenoid ligament was harvested, with its insertions on the scapular spine and on the capsule and glenoid left intact, for the histological analysis. Dissection revealed that a spinoglenoid ligament was present in all specimens. The ligament was found to form an irregular quadrangular shape. On gross examination, the deep fibers of the ligament extended from the lateral aspect of the scapular spine to the posterior part of the glenoid and the superficial fibers blended with the posterior aspect of the shoulder capsule. Histological sections demonstrated Sharpey fibers inserting into bone at the scapular spine and blending with the posterior aspect of the shoulder capsule to insert into the posterior surface of the glenoid, findings that confirmed the ligamentous nature of this structure. This study revealed the presence of the spinoglenoid ligament in all of the shoulders that were examined, with some variation in the size of the ligament.

Nanostructured biomaterials from electrospun demineralized bone matrix: a survey of processing and crosslinking strategies.

PubMed

Leszczak, Victoria; Place, Laura W; Franz, Natalee; Popat, Ketul C; Kipper, Matt J

2014-06-25

In the design of scaffolds for tissue engineering biochemical function and nanoscale features are of particular interest. Natural polymers provide a wealth of biochemical function, but do not have the processability of synthetic polymers, limiting their ability to mimic the hierarchy of structures in the natural extracellular matrix. Thus, they are often combined with synthetic carrier polymers to enable processing. Demineralized bone matrix (DBM), a natural polymer, is allograft bone with inorganic material removed. DBM contains the protein components of bone, which includes adhesion ligands and osteoinductive signals, such as important growth factors. Herein we describe a novel method for tuning the nanostructure of DBM through electrospinning without the use of a carrier polymer. This work surveys solvents and solvent blends for electrospinning DBM. Blends of hexafluoroisopropanol and trifluoroacetic acid are studied in detail. The effects of DBM concentration and dissolution time on solution viscosity are also reported and correlated to observed differences in electrospun fiber morphology. We also present a survey of techniques to stabilize the resultant fibers with respect to aqueous environments. Glutaraldehyde vapor treatment is successful at maintaining both macroscopic and microscopic structure of the electrospun DBM fibers. Finally, we report results from tensile testing of stabilized DBM nanofiber mats, and preliminary evaluation of their cytocompatibility. The DBM nanofiber mats exhibit good cytocompatibility toward human dermal fibroblasts (HDF) in a 4-day culture; neither the electrospun solvents nor the cross-linking results in any measurable residual cytotoxicity toward HDF.

PVDF-based semicrystalline-amorphous blends: Phase behavior and thermomechanical properties

NASA Astrophysics Data System (ADS)

Campo, Cheryl Josephine

Poly(vinylidene fluoride) [PVDF]-based semicrystalline-amorphous blends were studied to better understand the degree to which transition temperatures and mechanical properties could be varied as a function of composition. Changes in the amorphous component, processing parameters, MW, and filler content were used to manipulate blend properties. Compositional and MW series of PVDF:poly(vinyl acetate) [PVAc] blends were prepared and characterized. Varying PVDF content led to appreciable changes in crystallinity. In contrast, the effect of composition on blend glass transition temperature, Tg, was manifested only at low PVDF contents. The effect of MWPVA, on the 30:70 PVDF:PVAc composition was manifested primarily in the materials' viscoelastic response to deformation. Ternary blends of PVDF, PVAc, and poly(methyl methacrylate) [PMMA] showed limited miscibility with both a PVAc- and PMMA-rich amorphous phase apparent in all the compositions tested. PVDF:PMMA blends on the other hand exhibited good miscibility characterized by tunable Tg values which were further exploited by varying the processing conditions in order to obtain thermomechanical properties ideal for bio-related shape memory applications. PVDF:poly(ethyl methacrylate) [PEMA] blends, despite having very broad transitions, similarly exhibited desirable transition temperatures for in vivo actuation. The effect of boron nitride (BN), short carbon fibers (SCF), and clay on blend properties was also assessed. SCF filler in 50:50 PVDF:PMMA led mainly to the formation of PVDF crystals in the alpha form, clay was observed to promote growth of the beta crystal form, and BN led to a mixture of crystal forms. BN also exhibited interesting effects in the creep behavior of this system as well as the crystallization behavior of the 50:50 PVDF:PEMA blend, suppressed kinetic crystallization competing with enhanced nucleation effect under isothermal conditions observed in the latter. Depending on the processing conditions used, SCF was found to have similar nucleation effects in the 50:50 PVDF:PMMA blend but diminished degrees of crystallinity overall. Finally, shape memory behavior of PVDF:PVAc blends as well as SCF-filled 50:50 PVDF:PMMA was characterized using single and multiple shape memory cycles. Increasing PVDF content had a negative impact on PVDF:PVAc shape memory properties while increasing stress was found to have an enhancing effect as did low SCF filler content in 50:50 PVDF:PMMA.

Molecular Level Coating of Metal Oxide Particles

NASA Technical Reports Server (NTRS)

McDaniel, Patricia R. (Inventor); St.Clair, Terry L. (Inventor)

2002-01-01

Polymer encapsulated metal oxide particles are prepared by combining a polyamide acid in a polar osmotic solvent with a metal alkoxide solution. The polymer was imidized and the metal oxide formed simultaneously in a refluxing organic solvent. The resulting polymer-metal oxide is an intimately mixed commingled blend, possessing, synergistic properties of both the polymer and preceramic metal oxide. The encapsulated metal oxide particles have multiple uses including, being useful in the production of skin lubricating creams, weather resistant paints, as a filler for paper. making ultraviolet light stable filled printing ink, being extruded into fibers or ribbons, and coatings for fibers used in the production of composite structural panels.

Molecular Level Coating for Metal Oxide Particles

NASA Technical Reports Server (NTRS)

McDaniel, Patricia R. (Inventor); Saint Clair, Terry L. (Inventor)

2000-01-01

Polymer encapsulated metal oxide particles are prepared by combining a polyamide acid in a polar aprotic solvent with a metal alkoxide solution. The polymer was imidized and the metal oxide formed simultaneously in a refluxing organic solvent. The resulting polymer-metal oxide is an intimately mixed commingled blend, possessing synergistic properties of both the polymer and preceramic metal oxide. The encapsulated metal oxide particles have multiple uses including, being useful in the production of skin lubricating creams, weather resistant paints, as a filler for paper, making ultraviolet light stable filled printing ink, being extruded into fibers or ribbons, and coatings for fibers used in the production of composite structural panels.

Bis(trifluoromethanesulfonyl)imide-based ionic liquids grafted on graphene oxide-coated solid-phase microextraction fiber for extraction and enrichment of polycyclic aromatic hydrocarbons in potatoes and phthalate esters in food-wrap.

PubMed

Hou, Xiudan; Guo, Yong; Liang, Xiaojing; Wang, Xusheng; Wang, Lei; Wang, Licheng; Liu, Xia

2016-06-01

A class of novel, environmental friendly ionic liquids (ILs) were synthesized by on-fiber preparation strategy and modified on graphene oxide (GO)-coated stainless steel wire, which was used as a solid-phase microextraction (SPME) fiber for efficient enrichment of polycyclic aromatic hydrocarbons (PAHs) and phthalate esters (PAEs). Surface characteristic of the ILs and polymeric-ILs (PILs) fibers with the wave-structure were inspected by scanning electron microscope. The successfully synthesis of bis(trifluoromethanesulfonyl)imide (NTf2(-))-based ILs were also characterized by energy dispersive spectrometer analysis. Through the chromatograms of the proposed two ILs (1-aminoethyl-3-methylimidazolium bromide (C2NH2MIm(+)Br(-)), C2NH2MIm(+)NTf2(-)) and two PILs (polymeric 1-vinyl-3-hexylimidazolium bromide (poly(VHIm(+)Br(-))), poly(VHIm(+)NTf2(-)))-GO-coated fibers for the extraction of analytes, NTf2(-)-based PIL demonstrated higher extraction capacity for hydrophobic compounds than other as-prepared ILs. Analytical performances of the proposed fibers were investigated under the optimized extraction and desorption conditions coupled with gas chromatography (GC). Compared with the poly(VHIm(+)Br(-))-GO fiber, the poly(VHIm(+)NTf2(-))-GO SPME fiber brought wider linear ranges for analytes with correlation coefficient in the range of 0.9852-0.9989 and lower limits of detection ranging from 0.015-0.025μgL(-1). The obtained results indicated that the newly prepared PILs-GO coating was a feasible, selective and green microextraction medium, which could be suitable for extraction and determination of PAHs and PAEs in potatoes and food-wrap sample, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Electronic and Ionic Transport in Processable Conducting Polymers

DTIC Science & Technology

1991-05-28

doping with nitrosonium fluoborate. 6. Polypyrrole containing luminescent ions has been shown to be useful as in-situ probes of ion transport during...blends, ion transport, fibers, theoretical calculations ABSTRACT (Continue on reverse if necessary and identify by block number) A summary of the research...polymer/dopant ion interactions, symmereically and asymmetrically substituted poly(di-2-heterocycle-2,5-disubstitutedphenylenes), poly(5

[Rapid discriminating hogwash oil and edible vegetable oil using near infrared optical fiber spectrometer technique].

PubMed

Zhang, Bing-Fang; Yuan, Li-Bo; Kong, Qing-Ming; Shen, Wei-Zheng; Zhang, Bing-Xiu; Liu, Cheng-Hai

2014-10-01

In the present study, a new method using near infrared spectroscopy combined with optical fiber sensing technology was applied to the analysis of hogwash oil in blended oil. The 50 samples were a blend of frying oil and "nine three" soybean oil according to a certain volume ratio. The near infrared transmission spectroscopies were collected and the quantitative analysis model of frying oil was established by partial least squares (PLS) and BP artificial neural network The coefficients of determina- tion of calibration sets were 0.908 and 0.934 respectively. The coefficients of determination of validation sets were 0.961 and 0.952, the root mean square error of calibrations (RMSEC) was 0.184 and 0.136, and the root mean square error of predictions (RMSEP) was all 0.111 6. They conform to the model application requirement. At the same time, frying oil and qualified edible oil were identified with the principal component analysis (PCA), and the accurate rate was 100%. The experiment proved that near infrared spectral technology not only can quickly and accurately identify hogwash oil, but also can quantitatively detect hog- wash oil. This method has a wide application prospect in the detection of oil.

Chemical Composition, Starch Digestibility and Antioxidant Capacity of Tortilla Made with a Blend of Quality Protein Maize and Black Bean

PubMed Central

Grajales-García, Eva M.; Osorio-Díaz, Perla; Goñi, Isabel; Hervert-Hernández, Deisy; Guzmán-Maldonado, Salvador H.; Bello-Pérez, Luis A.

2012-01-01

Tortilla and beans are the basic components in the diet of people in the urban and rural areas of Mexico. Quality protein maize is suggested for tortilla preparation because it presents an increase in lysine and tryptophan levels. Beans contain important amounts of dietary fiber. The objective of this study was to prepare tortilla with bean and assesses the chemical composition, starch digestibility and antioxidant capacity using a quality protein maize variety. Tortilla with bean had higher protein, ash, dietary fiber and resistant starch content, and lower digestible starch than control tortilla. The hydrolysis rate (60 to 50%) and the predicted glycemic index (88 to 80) of tortilla decreased with the addition of bean in the blend. Extractable polyphenols and proanthocyanidins were higher in the tortilla with bean than control tortilla. This pattern produced higher antioxidant capacity of tortilla with bean (17.6 μmol Trolox eq/g) than control tortilla (7.8 μmol Trolox eq/g). The addition of bean to tortilla modified the starch digestibility and antioxidant characteristics of tortilla, obtaining a product with nutraceutical characteristics. PMID:22312252

Effects of sodium salt types on the intermolecular interaction of sodium alginate/antarctic krill protein composite fibers.

PubMed

Zhang, Rui; Guo, Jing; Liu, Yuanfa; Chen, Shuang; Zhang, Sen; Yu, Yue

2018-06-01

Sodium alginate (SA) and antarctic krill protein (AKP) were blended to fabricate the SA/AKP composite fibers by the conventional wet spinning method using 5% CaCl 2 as coagulation solution. The sodium salt was added to the SA/AKP solution to adjust the ionization degree and intermolecular interaction of composite system. The main purpose of this study is to investigate the influences of sodium salt types (NaCl, CH 3 COONa, Na 2 SO 4 ) on the intermolecular interaction of SA/AKP composite fibers. The intermolecular interaction, morphology, crystallinity, thermal stability and mechanical properties of SA/AKP composite fibers were analyzed by fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), x-ray diffraction (XRD), thermogravimetric analysis (TGA). The results show that the types of sodium salt have obvious influences on the content of both β-sheet, intermolecular hydrogen bond, breaking strength and surface morphology in SA/AKP composite fibers, but have a negligible effect on the crystallinity and thermal stability. Copyright © 2018 Elsevier Ltd. All rights reserved.

Estimation of integral curves from high angular resolution diffusion imaging (HARDI) data.

PubMed

Carmichael, Owen; Sakhanenko, Lyudmila

2015-05-15

We develop statistical methodology for a popular brain imaging technique HARDI based on the high order tensor model by Özarslan and Mareci [10]. We investigate how uncertainty in the imaging procedure propagates through all levels of the model: signals, tensor fields, vector fields, and fibers. We construct asymptotically normal estimators of the integral curves or fibers which allow us to trace the fibers together with confidence ellipsoids. The procedure is computationally intense as it blends linear algebra concepts from high order tensors with asymptotical statistical analysis. The theoretical results are illustrated on simulated and real datasets. This work generalizes the statistical methodology proposed for low angular resolution diffusion tensor imaging by Carmichael and Sakhanenko [3], to several fibers per voxel. It is also a pioneering statistical work on tractography from HARDI data. It avoids all the typical limitations of the deterministic tractography methods and it delivers the same information as probabilistic tractography methods. Our method is computationally cheap and it provides well-founded mathematical and statistical framework where diverse functionals on fibers, directions and tensors can be studied in a systematic and rigorous way.

Estimation of integral curves from high angular resolution diffusion imaging (HARDI) data

PubMed Central

Carmichael, Owen; Sakhanenko, Lyudmila

2015-01-01

We develop statistical methodology for a popular brain imaging technique HARDI based on the high order tensor model by Özarslan and Mareci [10]. We investigate how uncertainty in the imaging procedure propagates through all levels of the model: signals, tensor fields, vector fields, and fibers. We construct asymptotically normal estimators of the integral curves or fibers which allow us to trace the fibers together with confidence ellipsoids. The procedure is computationally intense as it blends linear algebra concepts from high order tensors with asymptotical statistical analysis. The theoretical results are illustrated on simulated and real datasets. This work generalizes the statistical methodology proposed for low angular resolution diffusion tensor imaging by Carmichael and Sakhanenko [3], to several fibers per voxel. It is also a pioneering statistical work on tractography from HARDI data. It avoids all the typical limitations of the deterministic tractography methods and it delivers the same information as probabilistic tractography methods. Our method is computationally cheap and it provides well-founded mathematical and statistical framework where diverse functionals on fibers, directions and tensors can be studied in a systematic and rigorous way. PMID:25937674

Linen Most Useful: Perspectives on Structure, Chemistry, and Enzymes for Retting Flax

PubMed Central

Akin, Danny E.

2013-01-01

The components of flax (Linum usitatissimum) stems are described and illustrated, with reference to the anatomy and chemical makeup and to applications in processing and products. Bast fiber, which is a major economic product of flax along with linseed and linseed oil, is described with particular reference to its application in textiles, composites, and specialty papers. A short history of retting methods, which is the separation of bast fiber from nonfiber components, is presented with emphasis on water retting, field retting (dew retting), and experimental methods. Past research on enzyme retting, particularly by the use of pectinases as a potential replacement for the current commercial practice of field retting, is reviewed. The importance and mechanism of Ca2+ chelators with pectinases in retting are described. Protocols are provided for retting of both fiber-type and linseed-type flax stems with different types of pectinases. Current and future applications are listed for use of a wide array of enzymes to improve processed fibers and blended yarns. Finally, potential lipid and aromatic coproducts derived from the dust and shive waste streams of fiber processing are indicated. PMID:25969769

Comparison of automated processing of flocked swabs with manual processing of fiber swabs for detection of nasal carriage of Staphylococcus aureus.

PubMed

Jones, Gillian; Matthews, Roger; Cunningham, Richard; Jenks, Peter

2011-07-01

The sensitivity of automated culture of Staphylococcus aureus from flocked swabs versus that of manual culture of fiber swabs was prospectively compared using nasal swabs from 867 patients. Automated culture from flocked swabs significantly increased the detection rate, by 13.1% for direct culture and 10.2% for enrichment culture.

A study on friability, hardness and fiber content analysis of fiber enriched milk tablet

NASA Astrophysics Data System (ADS)

Suzihaque, M. U. H.; Irfan, M. H.; Ibrahim, U. K.

2017-06-01

This study was performed to analyze the friability, hardness and fiber content of fiber enriched milk tablet derived from five different local fiber sources such as carrot, spinach, dragon fruit, mango and watermelon. Cow milk was mixed to complement with the tablet as a protein source. The powder were spray dried at 100°C, 120°C and 140°C and freeze dried at -60°C. The mixture of fruits and milk were made into equal ratio with the addition of 15 maltodextrin as a carrier. Tablets formed were used for friability and hardness test while dried powder were used for fiber content analysis. Dragon fruit tablet dried at 140°C have the highest friability with 11. 42 of weight loss. The second highest friability was spinach tablet dried at 100°C and 120°C drying temp erature with 9.30 and 9.28 respectively. The lowest friability was exhibited by carrot, mango and watermelon tablet at 100°C and dragon fruit at 120°C while carrot and spinach at 140°C. In contras t, none of the freeze dried tablets showed any weight loss hence they are not friable. For hardness test, all of the freeze dried showed to have higher tensile strength than spray dried, where carrot showed to be the highest at 2.27 Newton and the lowest were spray dried mango at 0.16 Newton. In fiber content analysis, freeze dried mango have the highest fiber content followed by freeze dried carrot and 140°C s pray dried carrot. It can be concluded that the higher the spray dry temperature, the more friable is the tablet. While, high friability leads to lower hardness of tablets. In terms of fiber content, the higher the spray dry temperature, the lower the fiber content found.

Plasma fatty acid changes following consumption of dietary oils containing n-3, n-6, and n-9 fatty acids at different proportions: preliminary findings of the Canola Oil Multicenter Intervention Trial (COMIT)

PubMed Central

2014-01-01

Background The Canola Oil Multicenter Intervention Trial (COMIT) was a randomized controlled crossover study designed to evaluate the effects of five diets that provided different oils and/or oil blends on cardiovascular disease (CVD) risk factors in individuals with abdominal obesity. The present objective is to report preliminary findings on plasma fatty acid profiles in volunteers with abdominal obesity, following the consumption of diets enriched with n-3, n-6 and n-9 fatty acids. Methods COMIT was conducted at three clinical sites, Winnipeg, Manitoba, Canada, Québec City, Québec, Canada and University Park, Pennsylvania, United States. Inclusion criteria were at least one of the followings: waist circumference (≥90 cm for males and ≥84 cm for females), and at least one other criterion: triglycerides ≥1.7 mmol/L, high density lipoprotein cholesterol <1 mmol/L (males) or <1.3 mmol/L (females), blood pressure ≥130 mmHg (systolic) and/or ≥85 mmHg (diastolic), and glucose ≥5.5 mmol/L. Weight-maintaining diets that included shakes with one of the dietary oil blends were provided during each of the five 30-day dietary phases. Dietary phases were separated by four-week washout periods. Treatment oils were canola oil, high oleic canola oil, high oleic canola oil enriched with docosahexaenoic acid (DHA), flax oil and safflower oil blend, and corn oil and safflower oil blend. A per protocol approach with a mixed model analysis was decided to be appropriate for data analysis. Results One hundred and seventy volunteers were randomized and 130 completed the study with a dropout rate of 23.5%. The mean plasma total DHA concentrations, which were analyzed among all participants as a measure of adherence, increased by more than 100% in the DHA-enriched phase, compared to other phases, demonstrating excellent dietary adherence. Conclusions Recruitment and retention strategies were effective in achieving a sufficient number of participants who completed the study protocol to enable sufficient statistical power to resolve small differences in outcome measures. It is expected that the study will generate important data thereby enhancing our understanding of the effects of n-3, n-6, and n-9 fatty acid-containing oils on CVD risks. Trial registration ClinicalTrials.gov NCT01351012. PMID:24754911

Green synthesis and characterization of hybrid collagen-cellulose-albumin biofibers from skin waste.

PubMed

Amsaveni, Manickam; Anumary, Ayyappan; Ashokkumar, Meiyazhagan; Chandrasekaran, Bangaru; Thanikaivelan, Palanisamy

2013-11-01

Collagen (C) and cellulose are prominent biopolymers from the animal and plant kingdom and widely used in bioengineering. Albumin, on the other hand, is the most abundant plasma protein present in mammalian blood. In this work, collagen extracted from animal skin waste was blended with hydroxyethyl cellulose (HEC) and bovine serum albumin (A) and wet-spun to form hybrid biodegradable C/HEC/A fibers. They were further cross-linked with glutaraldehyde vapors and analyzed. X-ray diffraction and infra-red spectroscopic studies of the hybrid fibers display peaks corresponding to collagen, cellulose, and albumin. Incorporation of cellulose into the biopolymeric matrix leads to a reasonable improvement in mechanical, swelling, and thermal properties of hybrid fibers. Addition of albumin improves the regularity of fiber surface without altering the porosity as observed under a microscope. Hence, the formed hybrid biofibers can be potentially used as a suture material as well as for different biomedical applications due to their improved properties.

Recent Trends in Sustainable Textile Waste Recycling Methods: Current Situation and Future Prospects.

PubMed

Pensupa, Nattha; Leu, Shao-Yuan; Hu, Yunzi; Du, Chenyu; Liu, Hao; Jing, Houde; Wang, Huaimin; Lin, Carol Sze Ki

2017-08-16

In recent years, there have been increasing concerns in the disposal of textile waste around the globe. The growth of textile markets not only depends on population growth but also depends on economic and fashion cycles. The fast fashion cycle in the textile industry has led to a high level of consumption and waste generation. This can cause a negative environmental impact since the textile and clothing industry is one of the most polluting industries. Textile manufacturing is a chemical-intensive process and requires a high volume of water throughout its operations. Wastewater and fiber wastes are the major wastes generated during the textile production process. On the other hand, the fiber waste was mainly created from unwanted clothes in the textile supply chain. This fiber waste includes natural fiber, synthetic fiber, and natural/synthetic blends. The natural fiber is mostly comprised of cellulosic material, which can be used as a resource for producing bio-based products. The main challenge for utilization of textile waste is finding the method that is able to recover sugars as monosaccharides. This review provides an overview of valorization of textile waste to value-added products, as well as an overview of different strategies for sugar recovery from cellulosic fiber and their hindrances.

Effect of fibre treatments on tensile properties of ethylene vinyl acetate/natural rubber/mengkuang leaf fibre (EVA/NR/MLF) thermoplastic elastomer composites

NASA Astrophysics Data System (ADS)

Hashim, Faiezah; Ismail, Hanafi; Rusli, Arjulizan

2017-07-01

Nowadays, a great attention has been dedicated to natural fibers as reinforcement for polymer composites. Natural fibers, compared to glass fibers, exhibit better mechanical properties, such as stiffness, impact strength, flexibility and modulus. However, certain drawbacks, such as the incompatibility between fibers and polymer matrices, the tendency to form aggregates during processing and the poor resistance to moisture, reduce the use of these natural fibers as reinforcements in polymers. Several treatments and modifications are being used to improve the adhesion between fibre and matrix. In this work, the effect of bleaching treatments using hydrogen peroxide in the Mengkuang leaf fibre (MLF) was evaluated on tensile properties of Ethylene Vinyl Acetate (EVA)/Natural Rubber (NR)/MLF composites. Treated MLF were mixed with the EVA/NR blend in Haake internal mixer at 120 °C and rotor speed of 50 rpm for 10 minutes. Fibre morphology and the fibre/matrix interface ware further characterized by scanning electron microscopy (SEM). The tensile strength was increased by about 8% as compared to the composites with untreated fibers. The increased adhesion between fiber and matrix was also observed by SEM. Thus, EVA/NR/MLF composites reinforced with the treated fibres exhibited better tensile properties than untreated EVA/NR/MLF composites.

In Darwin's Footsteps: An On and Off-Campus Approach to Teaching Evolutionary Theory and Animal Behavior

ERIC Educational Resources Information Center

Gillie, Lynn; Bizub, Anne L.

2012-01-01

The study of evolutionary theory and fieldwork in animal behavior is enriched when students leave the classroom so they may test their abilities to think and act like scientists. This article describes a course on evolutionary theory and animal behavior that blended on campus learning with field experience in the United States and in Ecuador and…

Improvement of texture and sensory properties of cakes by addition of potato peel powder with high level of dietary fiber and protein.

PubMed

Ben Jeddou, Khawla; Bouaziz, Fatma; Zouari-Ellouzi, Soumaya; Chaari, Fatma; Ellouz-Chaabouni, Semia; Ellouz-Ghorbel, Raoudha; Nouri-Ellouz, Oumèma

2017-02-15

Demand for health oriented products such as low calories and high fiber product is increasing. The aim of the present work was to determine the effect of the addition of potato peel powders as protein and dietary fiber source on the quality of the dough and the cake. Powders obtained from the two types of peel flour showed interesting water binding capacity and fat absorption capacity. Potato peel flours were incorporated in wheat flours at different concentration. The results showed that peel powders additionally considerably improved the Alveograph profile of dough and the texture of the prepared cakes. In addition color measurements showed a significant difference between the control dough and the dough containing potato peels. The replacement of wheat flour with the potato powders reduced the cake hardness significantly and the L(*) and b(*) dough color values. The increased consumption of cake enriched with potato peel fiber is proposed for health reasons. The study demonstrated that protein/fiber-enriched cake with good sensory quality could be produced by the substitution of wheat flour by 5% of potato peel powder. In addition and technological point of view, the incorporation of potato peel powder at 5% increase the dough strength and elasticity-to-extensibility ratio (P/L). Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Multistage open-tube trap for enrichment of part-per-trillion trace components of low-pressure (below 27-kPa) air samples

NASA Technical Reports Server (NTRS)

Ohara, D.; Vo, T.; Vedder, J. F.

1985-01-01

A multistage open-tube trap for cryogenic collection of trace components in low-pressure air samples is described. The open-tube design allows higher volumetric flow rates than densely packed glass-bead traps commonly reported and is suitable for air samples at pressures below 27 kPa with liquid nitrogen as the cryogen. Gas blends containing 200 to 2500 parts per trillion by volume each of ethane and ethene were sampled and hydrocarbons were enriched with 100 + or - 4 percent trap efficiency. The multistage design is more efficient than equal-length open-tube traps under the conditions of the measurements.

The recycling of comminuted glass-fiber-reinforced resin from electronic waste.

PubMed

Duan, Huabo; Jia, Weifeng; Li, Jinhui

2010-05-01

The reuse of comminuted glass-fiber-reinforced resin with various granularities gathered from printed circuit manufacturing residues was investigated. As fillers, these residues were converted into polymeric composite board by an extrusion and injection process using polypropylene as a bonding agent. The mechanical properties of the reproduced composite board were examined by considering the effects of mass fraction and glass-fiber distribution. Interfacial-layer micrograph analysis of the composite material fracture surface was used to study the fiber reinforcement mechanism. Results showed that using comminuted glass-fiber-reinforced resin as a filler material greatly enhanced the performance properties of the composite board. Although the length and diameter of filler varied, these variations had no appreciable effect on the mechanical properties of the processed board. Maximum values of 48.30 MPa for flexural strength, 31.34 MPa for tensile strength, and 31.34 J/m for impact strength were achieved from a composite board containing mass fractions of 30, 10, and 20% glass-fiber-reinforced resin waste, respectively. It was found that the maximum amount of recyclate that could be added to a composite board was 30% of weight. Beyond these percentages, the materials blend became unmanageable and the mixture less amenable to impregnation with fiber. Presented studies indicated that comminuted glass-fiber-reinforced resin waste-filled polypropylene composites are promising candidates for structural applications where high stiffness and fracture resistance are required.

Optimization of the contents of hollow glass microsphere and sodium hexametaphosphate for glass fiber vacuum insulation panel

NASA Astrophysics Data System (ADS)

Li, C. D.; Chen, Z. F.; Zhou, J. M.

2016-07-01

In this paper, various additive amounts of hollow glass microspheres (HGMs) and sodium hexametaphosphate (SHMP) powders were blended with flame attenuated glass wool (FAGW) to form hybrid core materials (HCMs) through the wet method. Among them, the SHMP was dissolved in the glass fiber suspension and coated on the surface of glass fibers while the HGMs were insoluble in the glass fiber suspension and filled in the fiber-fiber pores. The average pore diameter of the FAGW/HGM HCMs was 8-11 μm which was near the same as that of flame attenuated glass fiber mats (FAGMs, i.e., 10.5 µm). The tensile strength of the SHMP coated FAGMs was enhanced from 160 N/m to 370 N/m when SHMP content increased from 0 wt.% to 0.2 wt.%. By contrast, the tensile strength of the FAGW/HGM HCMs decreased from 160 N/m to 40 N/m when HGM content increased from 0 wt.% to 50 wt.%. Both the FAGW/HGM HCMs and SHMP coated FAGMs were vacuumed completely to form vacuum insulation panels (VIPs). The results showed that both the addition of SHMP and HGM led a slight increase in the thermal conductivity of the corresponding VIPs. To obtain a high-quality VIP, the optimal SHMP content and HGM content in glass fiber suspension was 0.12-0.2 wt.% and 0 wt.%.

Comparison of Automated Processing of Flocked Swabs with Manual Processing of Fiber Swabs for Detection of Nasal Carriage of Staphylococcus aureus▿‡

PubMed Central

Jones, Gillian; Matthews, Roger; Cunningham, Richard; Jenks, Peter

2011-01-01

The sensitivity of automated culture of Staphylococcus aureus from flocked swabs versus that of manual culture of fiber swabs was prospectively compared using nasal swabs from 867 patients. Automated culture from flocked swabs significantly increased the detection rate, by 13.1% for direct culture and 10.2% for enrichment culture. PMID:21525218

Physical properties and FTIR analysis of rice-oat flour and maize-oat flour based extruded food products containing olive pomace.

PubMed

Ying, DanYang; Hlaing, Mya Myintzu; Lerisson, Julie; Pitts, Keith; Cheng, Lijiang; Sanguansri, Luz; Augustin, Mary Ann

2017-10-01

Olive pomace, a waste stream from olive oil processing, was fractionated by centrifugation to obtain a supernatant and a flesh-enriched fraction, and freeze dried to obtain a powder. The dried supernatant contained 5.8% moisture, 4.8% protein, 3.5% fat, 3.5% ash, 82.4% carbohydrate (including 17.2% dietary fiber) and polyphenols (2970mg gallic acid equivalents (GAE)/100g). The dried flesh-enriched fraction, contained 5.9% moisture, 13.4% protein, 14.2% fat, 3.5% ash, 63.1% carbohydrate (including 42.7% dietary fiber) and polyphenols (1960mg GAE/100g). The extruded products using rice-oat flour or maize-oat flour mixtures as the base were formulated to contain 5% or 10% olive pomace fractions (dry basis). The extruded products with added olive pomace fractions has higher fiber (2-7g/100g) and polyphenol contents (67-161mg GAE/100g) compared to the corresponding mixtures of rice-oat flour base (0.92g/100g fiber, 20mg GAE/100g) or maize-oat flour base (3.2g/100g fiber, 20mg GAE/100g) without olive pomace fractions. Addition of olive pomace fractions reduced the die pressure and specific mechanical energy during extrusion and resulted in lower radial expansion in the extruded product. The impact of the addition of olive pomace fraction on physical characteristics of the extruded product is higher for rice-oat flour base than maize-oat flour base. The underlining mechanism was explained by FTIR analysis. FTIR showed that there were significant changes in the carbohydrate components and the structure of the proteins on extrusion, with consequent effects on the expansion and density of the extruded product. This study showed the feasibility of preparing fiber and polyphenol enriched extruded products by incorporation of olive pomace. This shows the potential of recovery and diversion of edible components from waste streams of olive oil processing for formulation of extruded products. Copyright © 2017 Elsevier Ltd. All rights reserved.

Apparent Km of mitochondria for oxygen computed from Vmax measured in permeabilized muscle fibers is lower in water enriched in oxygen by electrolysis than injection

PubMed Central

Zoll, Joffrey; Bouitbir, Jamal; Sirvent, Pascal; Klein, Alexis; Charton, Antoine; Jimenez, Liliana; Péronnet, François R; Geny, Bernard; Richard, Ruddy

2015-01-01

Background It has been suggested that oxygen (O2) diffusion could be favored in water enriched in O2 by a new electrolytic process because of O2 trapping in water superstructures (clathrates), which could reduce the local pressure/content relationships for O2 and facilitate O2 diffusion along PO2 gradients. Materials and methods Mitochondrial respiration was compared in situ in saponin-skinned fibers isolated from the soleus muscles of Wistar rats, in solution enriched in O2 by injection or the electrolytic process 1) at an O2 concentration decreasing from 240 µmol/L to 10 µmol/L (132 mmHg to 5 mmHg), with glutamate–malate or N, N, N′, N′-tetramethyl-p-phenylenediamine dihydrochloride (TMPD)–ascorbate (with antimycin A) as substrates; and 2) at increasing adenosine diphosphate (ADP) concentration with glutamate–malate as substrate. Results As expected, maximal respiration decreased with O2 concentration and, when compared to glutamate–malate, the apparent Km O2 of mitochondria for O2 was significantly lower with TMPD–ascorbate with both waters. However, when compared to the water enriched in O2 by injection, the Km O2 was significantly lower with both electron donors in water enriched in O2 by electrolysis. This was not associated with any increase in the sensitivity of mitochondria to ADP; no significant difference was observed for the Km ADP between the two waters. Conclusion In this experiment, a higher affinity of the mitochondria for O2 was observed in water enriched in O2 by electrolysis than by injection. This observation is consistent with the hypothesis that O2 diffusion can be facilitated in water enriched in O2 by the electrolytic process. PMID:26203225

Apparent Km of mitochondria for oxygen computed from Vmax measured in permeabilized muscle fibers is lower in water enriched in oxygen by electrolysis than injection.

PubMed

Zoll, Joffrey; Bouitbir, Jamal; Sirvent, Pascal; Klein, Alexis; Charton, Antoine; Jimenez, Liliana; Péronnet, François R; Geny, Bernard; Richard, Ruddy

2015-01-01

It has been suggested that oxygen (O2) diffusion could be favored in water enriched in O2 by a new electrolytic process because of O2 trapping in water superstructures (clathrates), which could reduce the local pressure/content relationships for O2 and facilitate O2 diffusion along PO2 gradients. Mitochondrial respiration was compared in situ in saponin-skinned fibers isolated from the soleus muscles of Wistar rats, in solution enriched in O2 by injection or the electrolytic process 1) at an O2 concentration decreasing from 240 µmol/L to 10 µmol/L (132 mmHg to 5 mmHg), with glutamate-malate or N, N, N', N'-tetramethyl-p-phenylenediamine dihydrochloride (TMPD)-ascorbate (with antimycin A) as substrates; and 2) at increasing adenosine diphosphate (ADP) concentration with glutamate-malate as substrate. As expected, maximal respiration decreased with O2 concentration and, when compared to glutamate-malate, the apparent Km O2 of mitochondria for O2 was significantly lower with TMPD-ascorbate with both waters. However, when compared to the water enriched in O2 by injection, the Km O2 was significantly lower with both electron donors in water enriched in O2 by electrolysis. This was not associated with any increase in the sensitivity of mitochondria to ADP; no significant difference was observed for the Km ADP between the two waters. In this experiment, a higher affinity of the mitochondria for O2 was observed in water enriched in O2 by electrolysis than by injection. This observation is consistent with the hypothesis that O2 diffusion can be facilitated in water enriched in O2 by the electrolytic process.

Polyphenol-Rich Bilberry Ameliorates Total Cholesterol and LDL-Cholesterol when Implemented in the Diet of Zucker Diabetic Fatty Rats

PubMed Central

Brader, Lea; Overgaard, Ann; Christensen, Lars P.; Jeppesen, Per B.; Hermansen, Kjeld

2013-01-01

BACKGROUND: Bilberries and blackcurrants are nutrient sources rich in bioactive components, including dietary fibers, polyphenols, and anthocyanins, which possess potent cardiovascular protective properties. Few studies investigating the cardio-protective effects of natural components have focused on whole bilberries or blackcurrants. OBJECTIVE: The aim of this trial was to investigate whether a diet enriched with bilberries or blackcurrants has beneficial effects on glucose metabolism, lipid profile, blood pressure, and expression of genes related to glucose and lipid metabolism. METHODS: Male Zucker Diabetic Fatty (ZDF) rats (n = 48) were randomly assigned to either a control, bilberry-enriched, blackcurrant-enriched, or fiber-enriched diet for 8 weeks ad libitum. Real-time quantitative PCR analysis was performed on liver, adipose, and muscle tissue. Berry polyphenol content was determined by HPLC and LC-MS analysis. RESULTS: Bilberry enrichment reduced total (-21%, p = 0.0132) and LDL-cholesterol (-60%, p = 0.0229) levels, but increased HDL-cholesterol to a lesser extent than in controls. This may partly be due to the altered hepatic liver X receptor-α expression (-24%, p < 0.001). Neither bilberries nor blackcurrants influenced glucose metabolism or blood pressure. Nevertheless, transcriptional analysis implied a better conservation of hepatic and adipocyte insulin sensitivity by bilberry enrichment. Anthocyanins constituted 91% and 87% of total polyphenol content in bilberries and blackcurrants, respectively. However, total anthocyanin content (3441 mg/100 g) was 4-fold higher in bilberries than in blackcurrants (871 mg/100 g). CONCLUSIONS: Bilberry consumption ameliorated total and LDL-cholesterol levels, but not HDL-cholesterol levels in ZDF rats. Neither bilberry nor blackcurrant enrichment delayed the development of diabetes or hypertension. Thus, in rats, bilberries may be valuable as a dietary preventive agent against hypercholesterolemia, probably by virtue of their high anthocyanin content. PMID:24841880

Physicochemical properties of cookies enriched with xylooligosaccharides.

PubMed

Ayyappan, P; Abirami, A; Anbuvahini, N A; Tamil Kumaran, P S; Naresh, M; Malathi, D; Antony, Usha

2016-07-01

The growing commercial importance of xylooligosaccharides is based on their beneficial health properties, particularly their ability to stimulate the growth and activity of intestinal bacteria such as Bifidobacterium and Lactobacillus species. Xylooligosaccharides are less sweet, acid, and heat stable, with low recommended levels of intake compared to other oligosaccharides. In view of the consumer demand for foods with low sugar, low fat, and high fiber contents, they are suitable for incorporation into bakery products. In this study, we have developed wheat-based cookies incorporated with xylooligosaccharides at 5%, 10%, and 15% levels. The nutritive value and physicochemical properties of the cookies changed with xylooligosaccharides incorporation; both crude fiber and dietary fiber contents increased by 14% and 35%, respectively, in the enriched cookies. The moisture levels increased with increase in the percentage of xylooligosaccharides incorporated. Cookies with 5% xylooligosaccharides were found most acceptable, although the color was slightly darker compared to the control, while cookies with 10% and 15% xylooligosaccharides were softer and darker and therefore less acceptable. Enrichment with xylooligosaccharides at 5% provided a product stable for 21 days at room temperature (25 ± 2℃). The storage stability of cookies with higher levels of xylooligosaccharides was less than the 5% xylooligosaccharides cookies and control. The retention of the prebiotic xylooligosaccharides in the products was relatively high (74%). © The Author(s) 2015.

Antioxidant activity and polyphenolic compound stability of lentil-orange peel powder blend in an extrusion process.

PubMed

Rathod, Rahul P; Annapure, Uday S

2017-03-01

Lentil contains substantial amount of protein, carbohydrate, fibre and other nutrients and orange peels powder rich in carbohydrate and fiber content The present study was aimed to investigate the effects of extrusion processing parameter on the level of total phenolic content (TPC), total flavonoid content (TFC), total tannin content and antioxidant activity of lentil-orange peel powder blend, also to investigate the possibility of blend as a candidate for production of protein rich extruded product by using response surface methodology. It was observed that, the physicochemical properties and sensory characteristics of lentil-orange peel based extrudate were highly dependent on process variables. The blend of lentil and orange peel powder has a huge potential for extrusion to produce ready-to-eat extruded with good acceptance. The overall best quality product was optimized and obtained at 16% moisture, 150 °C die temperature and 200 rpm screw speed. Extrusion process increased nutritional value of extruded product with TPC and TFC of 70.4 and 67.62% respectively and antioxidant activity of 60.6%. It showed higher stability at 150 °C with intermediate feed moisture content and despite the use of high temperatures in the extrusion-cooking is possible to minimize the loss of bioactive compounds to achieve products. Thus, results indicated that blend of lentil and orange peel may be used as raw material for the production of extruded snacks with great nutritional value.

Compressibility and resiliency properties of wilton type woven carpets produced with different fiber blend ratio

NASA Astrophysics Data System (ADS)

Osman, B.; Esin, S.; Sıdıka Ziba, O.

2017-10-01

Carpet is a textile structure that composed of three components: warp (stuffer and chain warp), weft and pile yarns. These textile products are used for areas which will stand up to the use of home, hotel, work place etc. Furthermore, the capable of carpets are related to it’s especially pile performance during use in various areas. During usage, carpets made from various type of raw materials of pile yarn also acts differently that these differentiate determines carpet performance, as well.This study was focused on the compression and resilience behaviour of carpet composed of 100% viscose and 100% acrylic pile yarns and blended pile yarns of blend ratios, 80%/20%, 50%/50% and 20%/80% viscose/acrylic. During the yarn production process, all spinning conditions were kept constant in order to eliminate the yarn production parameters. Five different types of wilton face to face carpet samples were produced from these yarns at the same pile height and pile density on Van de Wiele carpet weaving machine at 110 picks/min machine speed and 1/1 V carpet construction. Compressibility properties of carpets were examined whether blend ratio was statistically significant on carpet resilience or not. The behaviour of pile yarns under pressure is important that leads to understand the growth characteristic which is exposed to decrease and increase loadings during usage of carpet made from these yarns. Results indicated that blend ratio of pile yarns have significance effect on compression behaviour of carpet samples.

Petascale Simulations of the Morphology and the Molecular Interface of Bulk Heterojunctions

DOE PAGES

Carrillo, Jan-Michael Y.; Seibers, Zach; Kumar, Rajeev; ...

2016-07-14

Understanding how additives interact and segregate within bulk heterojunction (BHJ) thin films is critical for exercising control over structure at multiple length scales and delivering improvements in photovoltaic performance. The morphological evolution of poly(3-hexylthiophene) (P3HT) and phenyl-C 61-butyric acid methyl ester (PCBM) blends that are commensurate with the size of a BHJ thin film is examined using petascale coarse-grained molecular dynamics simulations. When comparing 2 component and 3 component systems containing short P3HT chains as additives undergoing thermal annealing we demonstrate that the short chains alter the morphol- ogy in apparently useful ways: They efficiently migrate to the P3HT/PCBM interface,more » increasing the P3HT domain size and interfacial area. Simulation results agree with depth profiles determined from neutron reflectometry measurements that reveal PCBM enrichment near substrate and air interfaces, but a decrease in that PCBM enrich- ment when a small amount of short P3HT chains are integrated into the BHJ blend. Atomistic simulations of the P3HT/PCBM blend interfaces show a non-monotonic dependence of the interfacial thickness as a function of number of repeat units in the oligomeric P3HT additive, and the thiophene rings orient parallel to the interfacial plane as they approach the PCBM domain. Using the nanoscale geometries of the P3HT oligomers, LUMO and HOMO energy levels calculated by density functional theory are found to be invariant across the donor/acceptor interface. Finally, these connections between additives, processing, and morphology at all length scales are generally useful for efforts to improve device performance.« less

Effect of film thickness on morphological evolution in dewetting and crystallization of polystyrene/poly(ε-caprolactone) blend films.

PubMed

Ma, Meng; He, Zhoukun; Yang, Jinghui; Chen, Feng; Wang, Ke; Zhang, Qin; Deng, Hua; Fu, Qiang

2011-11-01

In this Article, the morphological evolution in the blend thin film of polystyrene (PS)/poly(ε-caprolactone) (PCL) was investigated via mainly AFM. It was found that an enriched two-layer structure with PS at the upper layer and PCL at the bottom layer was formed during spinning coating. By changing the solution concentration, different kinds of crystal morphologies, such as finger-like, dendritic, and spherulitic-like, could be obtained at the bottom PCL layer. These different initial states led to the morphological evolution processes to be quite different from each other, so the phase separation, dewetting, and crystalline morphology of PS/PCL blend films as a function of time were studied. It was interesting to find that the morphological evolution of PS at the upper layer was largely dependent on the film thickness. For the ultrathin (15 nm) blend film, a liquid-solid/liquid-liquid dewetting-wetting process was observed, forming ribbons that rupture into discrete circular PS islands on voronoi finger-like PCL crystal. For the thick (30 nm) blend film, the liquid-liquid dewetting of the upper PS layer from the underlying adsorbed PCL layer was found, forming interconnected rim structures that rupture into discrete circular PS islands embedded in the single lamellar PCL dendritic crystal due to Rayleigh instability. For the thicker (60 nm) blend film, a two-step liquid-liquid dewetting process with regular holes decorated with dendritic PCL crystal at early annealing stage and small holes decorated with spherulite-like PCL crystal among the early dewetting holes at later annealing stage was observed. The mechanism of this unusual morphological evolution process was discussed on the basis of the entropy effect and annealing-induced phase separation.

Hypolipidemic effect of oils with balanced amounts of fatty acids obtained by blending and interesterification of coconut oil with rice bran oil or sesame oil.

PubMed

Reena, Malongil B; Lokesh, Belur R

2007-12-12

Blended oils comprising coconut oil (CNO) and rice bran oil (RBO) or sesame oil (SESO) with saturated fatty acid/monounsaturated fatty acid/polyunsaturated fatty acid at a ratio of 1:1:1 and polyunsaturated/saturated ratio of 0.8-1 enriched with nutraceuticals were prepared. Blended oils (B) were subjected to interesterification reaction using sn-1,3 specific Lipase from Rhizomucor miehei. Fatty acid composition and nutraceutical contents of the blended oil were not affected by interesterification reaction. Male Wistar rats were fed with AIN-76 diet containing 10% fat from CNO, RBO, SESO, CNO+RBO blend (B), CNO+SESO(B), CNO+RBO interesterified (I), or CNO+SESO(I) for 60 days. Serum total cholesterol (TC), low-density lipoprotein cholesterol, and triacylglycerols (TAGs) were reduced by 23.8, 32.4, and 13.9%, respectively, in rats fed CNO+RBO(B) and by 20.5, 34.1, and 12.9%, respectively, in rats fed CNO+SESO(B) compared to rats given CNO. Rats fed interesterified oils showed a decrease in serum TC, low-density lipoprotein cholesterol (LDL-C), and TAGs in CNO+RBO(I) by 35, 49.1, and 23.2 and by 33.3, 47, and 19.8% in CNO+SESO(I), respectively, compared to rats given CNO. Compared to rats fed CNO+RBO blended oils, rats on CNO+RBO interesterified oil showed a further decrease of 14.6, 24.7, and 10% in TC, LDL-C, and TAG. Rats fed CNO+SESO interesterified oils showed a decrease in serum TC, LDL-C, and TAG by 16.2, 19.6, and 7.8%, respectively, compared to rats given blended oils of CNO+SESO (B). Liver lipid analysis also showed significant change in the TC and TAG concentration in rats fed blended and interesterified oils of CNO+RBO and CNO+SESO compared to the rats given CNO. The present study suggests that feeding fats containing blended oils with balanced fatty acids lowers serum and liver lipids. Interesterified oils prepared using Lipase have a further lowering effect on serum and liver lipids even though the fatty acid composition of blended and interesterified oils remained same. These studies indicated that the atherogenic potentials of a saturated fatty acid containing CNO can be significantly decreased by blending with an oil rich in unsaturated lipids in appropriate amounts and interesterification of blended oil.

Long-term dietary effects on substrate selection and muscle fiber type in very-long-chain acyl-CoA dehydrogenase deficient (VLCAD(-/-)) mice.

PubMed

Tucci, Sara; Pearson, Sonja; Herebian, Diran; Spiekerkoetter, Ute

2013-04-01

Dietary fat restriction and increased carbohydrate intake are part of treatment in very-long-chain acyl-CoA dehydrogenase (VLCAD)-deficiency, the most common defect of long-chain fatty acid oxidation. The long-term impact of these interventions is unknown. We characterized here the effects of a fat-reduced, carbohydrate-enriched diet and an increased fat intake on energy metabolism in a mouse model of VLCAD-deficiency. Wild-type and VLCAD(-/-) mice were fed one year either with a normal (5.1%), a high fat (10.6%) or a low-fat, carbohydrate-enriched (2.6%) diet. Dietary effects on genes involved in lipogenesis, energy homeostasis and substrate selection were quantified by real-time-PCR. Acylcarnitines as sign of impaired energy production were determined in dried blood spots and tissues. White skeletal muscle was analyzed for muscle fiber type as well as for glycogen and triglyceride content. Both dietary modifications induced enhanced triacylglyceride accumulation in skeletal muscle and inhibition of glucose oxidation. This was accompanied by an up-regulation of genes coding for oxidative muscle fiber type I and a marked accumulation of acylcarnitines, especially prominent in the heart (164±2.8 in VLCAD(-/-) vs. 82.3±2.1 in WT μmol/mg) under a low-fat, carbohydrate-enriched diet. We demonstrate here that both dietary interventions with respect to the fat content of the diet reverse endogenous compensatory mechanisms in muscle that have evolved in VLCAD(-/-) mice resulting in pronounced energy deficiency. In particular, the low-fat carbohydrate-enriched diet was not effective in the long term. Further experiments are necessary to define the optimal energy provision for fatty acid oxidation defects. Copyright © 2013 Elsevier B.V. All rights reserved.

Feasibility study on the development of tough, moisture-resistant laminating resins

NASA Technical Reports Server (NTRS)

Brand, R. A.; Harrison, E. S.

1979-01-01

The potential of cyanate resins as replacement for epoxy resins in composites with graphite fiber reinforcement was investigated in an effort to provide improved moisture resistance and toughness in laminating systems at a projected cost, handleability, and processing requirements equivalent to 400 K (260 F) curing epoxies. Monomer synthesis, formulation, blending, resin preparation, catalysis studies, prepreg preparation, laminate fabrication, and testing are discussed. A graphite fiber reinforced laminate was developed with 95 percent retention of the original 363 K (180 F) flexural strength and 70 percent retention of the 363 K (180 F) short beam shear strength after 500 hour exposure to 95 + 7 relative humidity at 324 K (120 F).

Development of protein, dietary fiber, and micronutrient enriched extruded corn snacks.

PubMed

Shah, Faiz-Ul-Hassan; Sharif, Mian Kamran; Butt, Masood Sadiq; Shahid, Muhammad

2017-06-01

The study was aimed to develop protein, dietary fiber, and micronutrient enriched corn snacks through extrusion processing. Corn snacks supplemented with chickpea, defatted soy flour (20-40/100 g) and guar gum (7/100 g) were prepared through extrusion processing. Micronutrients (iron, zinc, iodine, and vitamins A, C, and folic acid) at recommended daily values were added in all formulations. Extruded corn snacks were analyzed for physical, textural, and sensory attributes. Results showed that piece density (0.34-0.44 g/cm 3 ), moisture (3.40-5.25%), water activity (0.203-0.361), hardness (64.4-133.2 N), and cohesiveness (0.25-0.44) was increased Whereas, expansion ratio (3.72-2.64), springiness (0.82-0.69), chewiness (1.63-0.42), and resilience (1.37-0.14) was decreased as supplementation with soy and chickpea flour increased from 20 to 40/100 g. Overall corn snack supplemented with 15/100 g of soy and 15/100 g of chickpea flour got the highest acceptance from the sensory panelists. The article focuses on physical, textural, and sensory attributes of extruded corn snacks enriched with protein, dietary fiber, and micronutrients Awareness about the importance of healthy snacks has grown among the consumers during the last decade. Extruded snacks developed using nutrient rich ingredients with good textural and sensory properties has always remained a challenge for the snack industry. Texture of the extruded snacks varies a lot with high levels of protein and dietary fiber. This study is helpful for the development of healthy snacks especially in developing countries lacking storage infrastructure or tropical environment. Nutrient rich extruded snacks can also be used to alleviate malnutrition by incorporating in school lunch programs. © 2016 Wiley Periodicals, Inc.

Ultraporous, Compressible, Wettable Polylactide/Polycaprolactone Sponges for Tissue Engineering.

PubMed

Mader, Michael; Jérôme, Valérie; Freitag, Ruth; Agarwal, Seema; Greiner, Andreas

2018-05-14

Ultraporous, degradable sponges made of either polylactide or of blends of polylactide/poly(ε-caprolactone) are prepared by freeze-drying of dispersions of short electrospun fibers and subsequent thermal annealing. The sponges feature ultrahigh porosity (99.6%), a hierarchical cellular structure, and high reversible compressibility with fast recovery from deformation in the dry as well as in the wet state. The sponge properties depend on the fiber dispersion concentration and the annealing temperature. Sponge characteristics like fiber density (2.5-20 mg/cm 3 ), size, shape, crystallinity, mechanical strength, wetability, and structural integrity are user adjustable. Cell culture experiments were successfully performed with Jurkat cells with Confocal Laser Scanning Microscopy and MTT staining showing rapid cell proliferation. Live/Dead staining demonstrated high viability of the seeded cells. The sponge characteristics and modifications investigated and presented here reveal that these sponges are highly promising for tissue engineering applications.

Filler/ Polycarbosilane Systems as CMC Matrix Precursors

NASA Technical Reports Server (NTRS)

Hurwitz, Frances I.

1998-01-01

Pyrolytic conversion of polymeric precursors to ceramics is accompanied by loss of volatiles and large volume changes. Infiltration of a low viscosity polymer into a fiber preform will fill small spaces within fiber tows by capillary forces, but create large matrix cracks within large, intertow areas. One approach to minimizing shrinkage and reducing the number of required infiltration cycles is to use particulate fillers. In this study, Starfire allylhydridopolycarbosilane (AHPCS) was blended with a silicon carbide powder, with and without dispersant, using shear mixing. The polymer and polymer/particle interactions were characterized using nuclear magnetic resonance, differential scanning calorimetry, thermogravimetric analysis and rheometry. Polymer/particulate slurries and suspensions were used to infiltrate a figidized preform of an eight ply five harness satin CG Nicalon fiber having a dual layer BN/SiC interface coating, and the resulting composites characterized by optical and scanning electron microscopy.

Method and apparatus for manufacturing gas tags

DOEpatents

Gross, K.C.; Laug, M.T.

1996-12-17

For use in the manufacture of gas tags employed in a gas tagging failure detection system for a nuclear reactor, a plurality of commercial feed gases each having a respective noble gas isotopic composition are blended under computer control to provide various tag gas mixtures having selected isotopic ratios which are optimized for specified defined conditions such as cost. Using a new approach employing a discrete variable structure rather than the known continuous-variable optimization problem, the computer controlled gas tag manufacturing process employs an analytical formalism from condensed matter physics known as stochastic relaxation, which is a special case of simulated annealing, for input feed gas selection. For a tag blending process involving M tag isotopes with N distinct feed gas mixtures commercially available from an enriched gas supplier, the manufacturing process calculates the cost difference between multiple combinations and specifies gas mixtures which approach the optimum defined conditions. The manufacturing process is then used to control tag blending apparatus incorporating tag gas canisters connected by stainless-steel tubing with computer controlled valves, with the canisters automatically filled with metered quantities of the required feed gases. 4 figs.

Method and apparatus for manufacturing gas tags

DOEpatents

Gross, Kenny C.; Laug, Matthew T.

1996-01-01

For use in the manufacture of gas tags employed in a gas tagging failure detection system for a nuclear reactor, a plurality of commercial feed gases each having a respective noble gas isotopic composition are blended under computer control to provide various tag gas mixtures having selected isotopic ratios which are optimized for specified defined conditions such as cost. Using a new approach employing a discrete variable structure rather than the known continuous-variable optimization problem, the computer controlled gas tag manufacturing process employs an analytical formalism from condensed matter physics known as stochastic relaxation, which is a special case of simulated annealing, for input feed gas selection. For a tag blending process involving M tag isotopes with N distinct feed gas mixtures commercially available from an enriched gas supplier, the manufacturing process calculates the cost difference between multiple combinations and specifies gas mixtures which approach the optimum defined conditions. The manufacturing process is then used to control tag blending apparatus incorporating tag gas canisters connected by stainless-steel tubing with computer controlled valves, with the canisters automatically filled with metered quantities of the required feed gases.

Effect of Fiber Esterification on Fundamental Properties of Oil Palm Empty Fruit Bunch Fiber/Poly(butylene adipate-co-terephthalate) Biocomposites

PubMed Central

Siyamak, Samira; Ibrahim, Nor Azowa; Abdolmohammadi, Sanaz; Yunus, Wan Md Zin Wan; Rahman, Mohamad Zaki AB

2012-01-01

A new class of biocomposites based on oil palm empty fruit bunch fiber and poly(butylene adipate-co-terephthalate) (PBAT), which is a biodegradable aliphatic aromatic co-polyester, were prepared using melt blending technique. The composites were prepared at various fiber contents of 10, 20, 30, 40 and 50 wt% and characterized. Chemical treatment of oil palm empty fruit bunch (EFB) fiber was successfully done by grafting succinic anhydride (SAH) onto the EFB fiber surface, and the modified fibers were obtained in two levels of grafting (low and high weight percentage gain, WPG) after 5 and 6 h of grafting. The FTIR characterization showed evidence of successful fiber esterification. The results showed that 40 wt% of fiber loading improved the tensile properties of the biocomposite. The effects of EFB fiber chemical treatments and various organic initiators content on mechanical and thermal properties and water absorption of PBAT/EFB 60/40 wt% biocomposites were also examined. The SAH-g-EFB fiber at low WPG in presence of 1 wt% of dicumyl peroxide (DCP) initiator was found to significantly enhance the tensile and flexural properties as well as water resistance of biocomposite (up to 24%) compared with those of untreated fiber reinforced composites. The thermal behavior of the composites was evaluated from thermogravimetric analysis (TGA)/differential thermogravimetric (DTG) thermograms. It was observed that, the chemical treatment has marginally improved the biocomposites’ thermal stability in presence of 1 wt% of dicumyl peroxide at the low WPG level of grafting. The improved fiber-matrix surface enhancement in the chemically treated biocomposite was confirmed by SEM analysis of the tensile fractured specimens. PMID:22408394

Effects of dietary fiber and its components on metabolic health.

PubMed

Lattimer, James M; Haub, Mark D

2010-12-01

Dietary fiber and whole grains contain a unique blend of bioactive components including resistant starches, vitamins, minerals, phytochemicals and antioxidants. As a result, research regarding their potential health benefits has received considerable attention in the last several decades. Epidemiological and clinical studies demonstrate that intake of dietary fiber and whole grain is inversely related to obesity, type two diabetes, cancer and cardiovascular disease (CVD). Defining dietary fiber is a divergent process and is dependent on both nutrition and analytical concepts. The most common and accepted definition is based on nutritional physiology. Generally speaking, dietary fiber is the edible parts of plants, or similar carbohydrates, that are resistant to digestion and absorption in the small intestine. Dietary fiber can be separated into many different fractions. Recent research has begun to isolate these components and determine if increasing their levels in a diet is beneficial to human health. These fractions include arabinoxylan, inulin, pectin, bran, cellulose, β-glucan and resistant starch. The study of these components may give us a better understanding of how and why dietary fiber may decrease the risk for certain diseases. The mechanisms behind the reported effects of dietary fiber on metabolic health are not well established. It is speculated to be a result of changes in intestinal viscosity, nutrient absorption, rate of passage, production of short chain fatty acids and production of gut hormones. Given the inconsistencies reported between studies this review will examine the most up to date data concerning dietary fiber and its effects on metabolic health.

Novel electrospun nanofibrous matrices prepared from poly(lactic acid)/poly(butylene adipate) blends for controlled release formulations of an anti-rheumatoid agent.

PubMed

Siafaka, Panoraia I; Barmbalexis, Panagiotis; Bikiaris, Dimitrios N

2016-06-10

In the present work, a series of novel formulations consisting of poly(lactic acid)/poly(butylene adipate) (PLA/PBAd) electrospun blends was examined as controlled release matrices for Leflunomide's active metabolite, Teriflunomide (TFL). The mixtures were prepared using different ratios of PLA and PBAd in order to produce nanofibrous matrices with different characteristics. Miscibility studies of the blended polymeric fibers were performed through differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). Hydrolytic degradation in the prepared fibers was evaluated at 37°C using a phosphate buffered saline solution. Different concentrations of (TFL) (5, 10, 15wt.%) were incorporated into nanofibers for examining the drug release behavior in simulated body fluids (SBF), at 37°C. The drug-loaded nanofibrous formulations were further characterized by Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy, DSC and XRD. Gel permeation chromatography (GPC) analysis was used to evaluate the mechanism of TFL release. Artificial neural networks (ANN) and multi-linear-regression (MLR) models were used to evaluate the effect of % content of PBAd (X1) and TFL (X2) on an initial burst effect and a dissolution behavior. It was found that PLA/PBAd nanofibers have different diameters depending on the ratio of used polyesters and added drug. TFL was incorporated in an amorphous form inside the polymeric nanofibers. In vitro release studies reveal that a drug release behavior is correlated with the size of the nanofibers, drug loading and matrix degradation after a specific time. ANN dissolution modeling showed increased correlation efficacy compared to MLR. Copyright © 2016 Elsevier B.V. All rights reserved.

Measured and Predicted Vapor Liquid Equilibrium of Ethanol-Gasoline Fuels with Insight on the Influence of Azeotrope Interactions on Aromatic Species Enrichment and Particulate Matter Formation in Spark Ignition Engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ratcliff, Matthew A; McCormick, Robert L; Burke, Stephen

A relationship has been observed between increasing ethanol content in gasoline and increased particulate matter (PM) emissions from direct injection spark ignition (DISI) vehicles. The fundamental cause of this observation is not well understood. One potential explanation is that increased evaporative cooling as a result of ethanol's high HOV may slow evaporation and prevent sufficient reactant mixing resulting in the combustion of localized fuel rich regions within the cylinder. In addition, it is well known that ethanol when blended in gasoline forms positive azeotropes which can alter the liquid/vapor composition during the vaporization process. In fact, it was shown recentlymore » through a numerical study that these interactions can retain the aromatic species within the liquid phase impeding the in-cylinder mixing of these compounds, which would accentuate PM formation upon combustion. To better understand the role of the azeotrope interactions on the vapor/liquid composition evolution of the fuel, distillations were performed using the Advanced Distillation Curve apparatus on carefully selected samples consisting of gasoline blended with ethanol and heavy aromatic and oxygenated compounds with varying vapor pressures, including cumene, p-cymene, 4-tertbutyl toluene, anisole, and 4-methyl anisole. Samples collected during the distillation indicate an enrichment of the heavy aromatic or oxygenated additive with an increase in initial ethanol concentration from E0 to E30. A recently developed distillation and droplet evaporation model is used to explore the influence of dilution effects versus azeotrope interactions on the aromatic species enrichment. The results suggest that HOV-cooling effects as well as aromatic species enrichment behaviors should be considered in future development of predictive indices to forecast the PM potential of fuels containing oxygenated compounds with comparatively high HOV.« less

Compressible or incompressible blend of interacting monodisperse star and linear polymers near a surface.

PubMed

Batman, Richard; Gujrati, P D

2008-03-28

We consider a lattice model of a mixture of repulsive, attractive, or neutral monodisperse star (species A) and linear (species B) polymers with a third monomeric species C, which may represent free volume. The mixture is next to a hard, infinite plate whose interactions with A and C can be attractive, repulsive, or neutral. These two interactions are the only parameters necessary to specify the effect of the surface on all three components. We numerically study monomer density profiles using the method of Gujrati and Chhajer that has already been previously applied to study polydisperse and monodisperse linear-linear blends next to surfaces. The resulting density profiles always show an enrichment of linear polymers in the immediate vicinity of the surface due to entropic repulsion of the star core. However, the integrated surface excess of star monomers is sometimes positive, indicating an overall enrichment of stars. This excess increases with the number of star arms only up to a certain critical number and decreases thereafter. The critical arm number increases with compressibility (bulk concentration of C). The method of Gujrati and Chhajer is computationally ultrafast and can be carried out on a personal computer (PC), even in the incompressible case, when simulations are unfeasible. Calculations of density profiles usually take less than 20 min on PCs.

Experiences of nursing undergraduates on a redesigned blended communication module: A descriptive qualitative study.

PubMed

Shorey, Shefaly; Siew, An Ling; Ang, Emily

2018-02-01

Education is going through accelerated changes to accommodate the needs of contemporary students. However, there are ongoing concerns regarding the quality of education in communication skills for nurses and other healthcare professionals. Many studies have been conducted to evaluate the effectiveness of a blended learning pedagogical tool in enhancing the learning of nursing undergraduates. However, little is known about students' experiences of a blended learning model for teaching communication skills. To explore first year nursing students' experiences of the blended learning design adopted in a communication module. A descriptive qualitative design was adopted. Data were collected in the form of written reflections from 74 first year nursing undergraduates who were enrolled in a university-affiliated nursing school. Students were asked to complete an online reflective exercise regarding an undergraduate communication module on their last day of class, and the submitted reflections were analyzed. A thematic analysis was conducted and ethics approval was obtained for this study. Six overarching themes and fifteen subthemes were generated. The six overarching themes were: 1) Helpful and engaging classroom experience, 2) valuable online activities, 3) meaningful assessment, 4) appreciation for interprofessional education, 5) personal enrichment, and 6) overall feedback and recommendations. The students in this study felt that the blended pedagogy communication module enhanced their learning and boosted their confidence in facing similar situations. Interprofessional education was well-accepted among students as they attained a deeper understanding on the importance of interprofessional learning and an appreciation towards other professionals. Blended pedagogy can be used in teaching communication skills to nursing students to provide a holistic and up-to-date learning experience. Future studies should consider engaging students in face-to-face interviews to obtain a deeper understanding on their experiences of a blended pedagogy incorporated communication module. Copyright © 2017 Elsevier Ltd. All rights reserved.

Simultaneous enrichment of denitrifying anaerobic methane-oxidizing microorganisms and anammox bacteria in a hollow-fiber membrane biofilm reactor.

PubMed

Ding, Zhao-Wei; Lu, Yong-Ze; Fu, Liang; Ding, Jing; Zeng, Raymond J

2017-01-01

In this study, the coculture system of denitrifying anaerobic methane oxidation (DAMO) microbes and anaerobic ammonium oxidation (anammox) bacteria was successfully enriched in a hollow-fiber membrane biofilm reactor (HfMBR) using freshwater sediment as the inoculum. The maximal removal rates of nitrate and ammonium were 78 mg N/L/day (131 mg N/m 2 /day) and 26 mg N/L/day (43 mg N/m 2 /day), respectively. Due to the high rate of methane mass transfer in HfMBR, the activity of DAMO archaea continued to increase during the enrichment period, indicating that HfMBR could be a powerful tool to enrich DAMO microorganisms. Effects of partial methane pressure, temperature, and pH on the cocultures were obvious. However, the microbial activity in HfMBR could be recovered quickly after the shock change of environmental factors. Furthermore, the result also found that DAMO bacteria likely had a stronger competitive advantage than anammox bacteria under the operating conditions in this study. High-throughput sequencing 16S rRNA genes illustrated that the dominant microbes were NC10, Euryarchaeota, Proteobacteria, Planctomycetes, and Chlorobi with relative abundance of 38.8, 26.2, 13.78, 6.2, and 3.6 %, respectively.

Glutamate and Dynorphin Release from a Subcellular Fraction Enriched in Hippocampal Mossy Fiber Synaptosomes

DTIC Science & Technology

1988-01-01

presence of extrasynaptosomal calcium . while only 3(0- of the evoked release of glutamate was calcium -dependent. D-aspartate. which exchanges glutamate...out of the cytoplasmic pool. virtually eliminated the calcium -independent component of glutamate release. This synaptosomal preparation will be useful...investigation of their presynaptic mechanisms ol action. l" Hippocampus Mossy fiber expansions Synaptosomes Glutamate Dynorphin Peptides Opioids Release Calcium

Novel Catalyst for the Chirality Selective Synthesis of Single Walled Carbon Nanotubes

DTIC Science & Technology

2015-05-12

hierarchical structures comprising nitrogen- doped reduced GO (rGO) and acid- oxidized SWCNTs was produced using a linear hydrothermal microreactor. Fiber...structures comprising nitrogen- doped reduced GO (rGO) and acidoxidized SWCNTs was produced using a linear hydrothermal microreactor. Fiber micro... doped into Co/SiO2 catalysts to change their chirality selectivity. Further, enrichment of (9,8) nanotubes was carried out by extraction using fluorene

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krasnov, Igor, E-mail: Igor.Krasnov@hzg.de; Müller, Martin, E-mail: Martin.Mueller@hzg.de; Institute of Materials Research, Helmholtz-Zentrum Geesthacht

An optically active bio-material is created by blending natural silk fibers with photoisomerizable chromophore molecules—azobenzenebromide (AzBr). The material converts the energy of unpolarized light directly into mechanical work with a well-defined direction of action. The feasibility of the idea to produce optically driven microsized actuators on the basis of bio-material (silk) is proven. The switching behavior of the embedded AzBr molecules was studied in terms of UV/Vis spectroscopy. To test the opto-mechanical properties of the modified fibers and the structural changes they undergo upon optically induced switching, single fiber X-ray diffraction with a micron-sized synchrotron radiation beam was combined inmore » situ with optical switching as well as with mechanical testing and monitoring. The crystalline regions of silk are not modified by the presence of the guest molecules, hence occupy only the amorphous part of the fibers. It is shown that chromophore molecules embedded into fibers can be reversibly switched between the trans and cis conformation by illumination with light of defined wavelengths. The host fibers respond to this switching with a variation of the internal stress. The amplitude of the mechanical response is independent of the applied external stress and its characteristic time is shorter than the relaxation time of the usual mechanical response of silk.« less

Impact Strength and Flexural Properties Enhancement of Methacrylate Silane Treated Oil Palm Mesocarp Fiber Reinforced Biodegradable Hybrid Composites

PubMed Central

Ibrahim, Nor Azowa; Ariffin, Hidayah; Yunus, Wan Md. Zin Wan

2014-01-01

Natural fiber as reinforcement filler in polymer composites is an attractive approach due to being fully biodegradable and cheap. However, incompatibility between hydrophilic natural fiber and hydrophobic polymer matrix restricts the application. The current studies focus on the effects of incorporation of silane treated OPMF into polylactic acid (PLA)/polycaprolactone (PCL)/nanoclay/OPMF hybrid composites. The composites were prepared by melt blending technique and characterize the composites with Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). FTIR spectra indicated that peak shifting occurs when silane treated OPMF was incorporated into hybrid composites. Based on mechanical properties results, incorporation of silane treated OPMF enhances the mechanical properties of unmodified OPMF hybrid composites with the enhancement of flexural and impact strength being 17.60% and 48.43%, respectively, at 10% fiber loading. TGA thermogram shows that incorporation of silane treated OPMF did not show increment in thermal properties of hybrid composites. SEM micrographs revealed that silane treated OPMF hybrid composites show good fiber/matrix adhesion as fiber is still embedded in the matrix and no cavity is present on the surface. Water absorption test shows that addition of less hydrophilic silane treated OPMF successfully reduces the water uptake of hybrid composites. PMID:25254230

Impact strength and flexural properties enhancement of methacrylate silane treated oil palm mesocarp fiber reinforced biodegradable hybrid composites.

PubMed

Eng, Chern Chiet; Ibrahim, Nor Azowa; Zainuddin, Norhazlin; Ariffin, Hidayah; Yunus, Wan Md Zin Wan

2014-01-01

Natural fiber as reinforcement filler in polymer composites is an attractive approach due to being fully biodegradable and cheap. However, incompatibility between hydrophilic natural fiber and hydrophobic polymer matrix restricts the application. The current studies focus on the effects of incorporation of silane treated OPMF into polylactic acid (PLA)/polycaprolactone (PCL)/nanoclay/OPMF hybrid composites. The composites were prepared by melt blending technique and characterize the composites with Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). FTIR spectra indicated that peak shifting occurs when silane treated OPMF was incorporated into hybrid composites. Based on mechanical properties results, incorporation of silane treated OPMF enhances the mechanical properties of unmodified OPMF hybrid composites with the enhancement of flexural and impact strength being 17.60% and 48.43%, respectively, at 10% fiber loading. TGA thermogram shows that incorporation of silane treated OPMF did not show increment in thermal properties of hybrid composites. SEM micrographs revealed that silane treated OPMF hybrid composites show good fiber/matrix adhesion as fiber is still embedded in the matrix and no cavity is present on the surface. Water absorption test shows that addition of less hydrophilic silane treated OPMF successfully reduces the water uptake of hybrid composites.

Microbial communities involved in methane production from hydrocarbons in oil sands tailings.

PubMed

Siddique, Tariq; Penner, Tara; Klassen, Jonathan; Nesbø, Camilla; Foght, Julia M

2012-09-04

Microbial metabolism of residual hydrocarbons, primarily short-chain n-alkanes and certain monoaromatic hydrocarbons, in oil sands tailings ponds produces large volumes of CH(4) in situ. We characterized the microbial communities involved in methanogenic biodegradation of whole naphtha (a bitumen extraction solvent) and its short-chain n-alkane (C(6)-C(10)) and BTEX (benzene, toluene, ethylbenzene, and xylenes) components using primary enrichment cultures derived from oil sands tailings. Clone libraries of bacterial 16S rRNA genes amplified from these enrichments showed increased proportions of two orders of Bacteria: Clostridiales and Syntrophobacterales, with Desulfotomaculum and Syntrophus/Smithella as the closest named relatives, respectively. In parallel archaeal clone libraries, sequences affiliated with cultivated acetoclastic methanogens (Methanosaetaceae) were enriched in cultures amended with n-alkanes, whereas hydrogenotrophic methanogens (Methanomicrobiales) were enriched with BTEX. Naphtha-amended cultures harbored a blend of these two archaeal communities. The results imply syntrophic oxidation of hydrocarbons in oil sands tailings, with the activities of different carbon flow pathways to CH(4) being influenced by the primary hydrocarbon substrate. These results have implications for predicting greenhouse gas emissions from oil sands tailings repositories.

Improving agar electrospinnability with choline-based deep eutectic solvents.

PubMed

Sousa, Ana M M; Souza, Hiléia K S; Uknalis, Joseph; Liu, Shih-Chuan; Gonçalves, Maria P; Liu, LinShu

2015-09-01

Very recently our group has produced novel agar-based fibers by an electrospinning technique using water as solvent and polyvinyl alcohol (PVA) as co-blending polymer. Here, we tested the deep eutectic solvent (DES), (2-hydroxyethyl)trimethylammonium chloride/urea prepared at 1:2 molar ratio, as an alternative solvent medium for agar electrospinning. The electrospun materials were collected with an ethanol bath adapted to a previous electrospinning set-up. One weight percent agar-in-DES showed improved viscoelasticity and hence, spinnability, when compared to 1 wt% agar-in-water and pure agar nanofibers were successfully electrospun if working above the temperature of sol-gel transition (∼80 °C). By changing the solvent medium we decreased the PVA concentration (5 wt% starting solution) and successfully produced composite fibers with high agar contents (50/50 agar/PVA). Best composite fibers were formed with the 50/50 and 30/70 agar/PVA solutions. These fibers were mechanically resistant, showed tailorable surface roughness and diverse size distributions, with most of the diameters falling in the sub-micron range. Both nano and micro forms of agar fibers (used separately or combined) may have potential for the design of new and highly functional agar-based materials. Published by Elsevier B.V.

[Efficiency of application of the enriched bakery products in children nutrition].

PubMed

Koryachkina, S Ya; Ladnova, O L; Lublinsky, S L; Kholodova, E N

2015-01-01

The results of the research devoted to an assessment of efficiency of application of the enriched bakery products in nutrition of school students have been presented. Composition and technology of the enriched bakery products have been developed. The influence of enrichers on the basis of proteins of whey, plasma of blood, hemoglobin, calcium and iodinated components and food fibers on the nutritive and energy value of bakery products has been defined. The consumption of 100 g of the enriched bakery products provides a significant amount of protein--12.5-23% of the recommended daily intake (RDI), to satisfy daily need of school students in calcium up to 13.4%, in iron--up to 20%, iodine--12.5% and food fibers--17.3%. When comparing blood hemoglobin content in school students after inclusion in a diet of the enriched bakery products, the lack of significant changes of this indicator in children with normal hemoglo- bin content has been determined that is the confirmation of safety of use of the products enriched with hem iron. At the same time, normalization of hemoglobin level in children (9.7%) with the initial threshold and lowered hemoglobin indicators is noted. The reliable increase in the content of hemoglobin in this group of children from 112 ± 3 to 131 ± 6 g/l was established (p ≤ 0.05). Positive dynamics of the content of iodine in urine at school students with initial deficiency of iodine under administration of the bread enriched with iodine has been defined. Ioduria indicators authentically increased from 88 ± 10 to 116 ± 9 mkg/l (p ≤ 0.05). Before diet correction in 53 from 59 children surveyed in the Stavropol region, a mild lack of iodine has been revealed (iodine levels less than 100 mkg/l urine), while after bread intake--only in 7 (11.9%) students.

Effect of compounding approaches on fiber dispersion and performance of poly(lactic acid)/cellulose nanocrystal composite blown films

Treesearch

Sonal S. Karkhanis; Laurent M. Matuana; Nicole M. Stark; Ronald C. Sabo

2017-01-01

This study was aimed to identify the best approach for incorporating cellulose nanocrystals (CNCs) into a poly(lactic acid) (PLA) matrix by examining two different CNC addition approaches. The first approach consisted of melt blending PLA and CNCs in a three-piece internal mixer whereas the second method involved the direct dry mixing of PLA and CNCs. The prepared...

Influence of processing conditions on apparent viscosity and system parameters during extrusion of distiller's dried grains-based snacks.

PubMed

Singha, Poonam; Muthukumarappan, Kasiviswanathan; Krishnan, Padmanaban

2018-01-01

A combination of different levels of distillers dried grains processed for food application (FDDG), garbanzo flour and corn grits were chosen as a source of high-protein and high-fiber extruded snacks. A four-factor central composite rotatable design was adopted to study the effect of FDDG level, moisture content of blends, extrusion temperature, and screw speed on the apparent viscosity, mass flow rate or MFR, torque, and specific mechanical energy or SME during the extrusion process. With increase in the extrusion temperature from 100 to 140°C, apparent viscosity, specific mechanical energy, and torque value decreased. Increase in FDDG level resulted in increase in apparent viscosity, SME and torque. FDDG had no significant effect (p > .5) on mass flow rate. SME also increased with increase in the screw speed which could be due to the higher shear rates at higher screw speeds. Screw speed and moisture content had significant negative effect ( p  <   .05) on the torque. The apparent viscosity of dough inside the extruder and the system parameters were affected by the processing conditions. This study will be useful for control of extrusion process of blends containing these ingredients for the development of high-protein high-fiber extruded snacks.

Process for producing silicon nitride based articles of high fracture toughness and strength

DOEpatents

Huckabee, Marvin; Buljan, Sergej-Tomislav; Neil, Jeffrey T.

1991-01-01

A process for producing a silicon nitride-based article of improved fracture toughness and strength. The process involves densifying to at least 98% of theoretical density a mixture including (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 .mu.m and a surface area of about 8-12 m.sup.2 /g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 .mu.m and a surface area of about 2-4 m.sup.2 /g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. Optionally, the mixture may be blended with a binder and injection molded to form a green body, which then may be densified by, for example, hot isostatic pressing.

Process for producing silicon nitride based articles of high fracture toughness and strength

DOEpatents

Huckabee, M.; Buljan, S.T.; Neil, J.T.

1991-09-10

A process for producing a silicon nitride-based article of improved fracture toughness and strength is disclosed. The process involves densifying to at least 98% of theoretical density a mixture including (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 [mu]m and a surface area of about 8-12 m[sup 2]/g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 [mu]m and a surface area of about 2-4 m[sup 2]/g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. Optionally, the mixture may be blended with a binder and injection molded to form a green body, which then may be densified by, for example, hot isostatic pressing.

Mixture Design Applied to the Development of Chickpea-Based Gluten-Free Bread with Attractive Technological, Sensory, and Nutritional Quality.

PubMed

Santos, Fernanda G; Fratelli, Camilly; Muniz, Denise G; Capriles, Vanessa D

2018-01-01

The aim of the study was utilized chickpea to create appealing, nutritious, and palatable gluten-free bread (GFB). The performance of chickpea flour (CF) in single and composite GFB formulations was studied with a mixture design and response surface methodology. Six simplex-centroid designs for 3 ingredients were used to identify the ideal proportions of CF in various blends with cassava starch (CS), maize starch (MS), potato starch (PS), and rice flour (RF) achieving the best physical properties. For each design, 3 single, 3 binary, and 3 ternary formulations were prepared. The results showed that CF alone is suitable for bread production, resulting in GFB with higher volume and crumb firmness and lower crumb moisture than single formulations of other raw materials. However, the interactions between CF and PS or CS enhanced the loaf volume and decreased the crumb firmness values. The GFB prepared with only CF was accepted (overall acceptability score of 7.1- on a 10-cm scale). Nevertheless, the composite formulations prepared with CF75:PS25 or CF75:CS25 (flour basis) received overall acceptability scores of 8.2, like those of their white GFB, prepared with RF50:PS50 blend (flour basis), and wheat bread counterparts, used as positive controls. Compared to white GFB, both composite formulations presented nearly a twofold increase in ash and protein contents and a threefold increase in total fiber content. These results show that blends of CF75:PS25 or CF75:CS25 can be used to develop GFB with a good physical and sensory properties, as well as an enhanced nutritional composition. Gluten-free bread (GFB) made with 75% chickpea flour (CF) blend with 25% potato or cassava starch showed improved total minerals, protein and dietary fiber content and bread quality characteristics. Therefore, CF is a valuable ingredient for food technologists in manufacturing better-tasting and healthy GFB, which is important for consumers with gluten-related disorders since GFB often lack nutrition content, appearance, texture, and mouthfeel. © 2017 Institute of Food Technologists®.

A review of evolution of electrospun tissue engineering scaffold: From two dimensions to three dimensions.

PubMed

Ngadiman, Nor Hasrul Akhmal; Noordin, M Y; Idris, Ani; Kurniawan, Denni

2017-07-01

The potential of electrospinning process to fabricate ultrafine fibers as building blocks for tissue engineering scaffolds is well recognized. The scaffold construct produced by electrospinning process depends on the quality of the fibers. In electrospinning, material selection and parameter setting are among many factors that contribute to the quality of the ultrafine fibers, which eventually determine the performance of the tissue engineering scaffolds. The major challenge of conventional electrospun scaffolds is the nature of electrospinning process which can only produce two-dimensional electrospun mats, hence limiting their applications. Researchers have started to focus on overcoming this limitation by combining electrospinning with other techniques to fabricate three-dimensional scaffold constructs. This article reviews various polymeric materials and their composites/blends that have been successfully electrospun for tissue engineering scaffolds, their mechanical properties, and the various parameters settings that influence the fiber morphology. This review also highlights the secondary processes to electrospinning that have been used to develop three-dimensional tissue engineering scaffolds as well as the steps undertaken to overcome electrospinning limitations.

Combustion characteristics and arsenic retention during co-combustion of agricultural biomass and bituminous coal.

PubMed

Zhou, Chuncai; Liu, Guijian; Wang, Xudong; Qi, Cuicui; Hu, Yunhu

2016-08-01

A combination of thermogravimetric analysis (TG) and laboratory-scale circulated fluidized bed combustion experiment was conducted to investigate the thermochemical, kinetic and arsenic retention behavior during co-combustion bituminous coal with typical agricultural biomass. Results shown that ignition performance and thermal reactivity of coal could be enhanced by adding biomass in suitable proportion. Arsenic was enriched in fly ash and associated with fine particles during combustion of coal/biomass blends. The emission of arsenic decreased with increasing proportion of biomass in blends. The retention of arsenic may be attributed to the interaction between arsenic and fly ash components. The positive correlation between calcium content and arsenic concentration in ash suggesting that the arsenic-calcium interaction may be regarded as the primary mechanism for arsenic retention. Copyright © 2016 Elsevier Ltd. All rights reserved.

Using cereal to increase dietary fiber intake to the recommended level and the effect of fiber on bowel function in healthy persons consuming North American diets.

PubMed

Vuksan, Vladimir; Jenkins, Alexandra L; Jenkins, David J A; Rogovik, Alexander L; Sievenpiper, John L; Jovanovski, Elena

2008-11-01

Dietary fiber intake remains low despite increasing evidence for its health benefits, including laxation. We aimed to assess the effects of increasing fiber intake on bowel habits and gastrointestinal tolerance in healthy persons consuming a typical Canadian or US diet. Under a randomized crossover design, 23 free-living participants consumed a typical Canadian or US diet (35% fat, 12 g fiber/d) and received 25.0-28.7 g fiber/d from each of 5 breakfast cereals: All-Bran (AB), Bran Buds with Corn (BBC), Bran Buds with Psyllium (BBP), BBC with viscous fiber blend (VFB), or a low-fiber control for 3 wk, with each study arm separated by a washout of >/=1 wk. Seven-day stool collections and a symptom diary were obtained during the last week of each study arm. All study cereals induced significant (P < 0.05) increases in fecal bulk from the control diet at 128 +/- 38 g to 199 +/- 56, 199 +/- 57, 247 +/- 87, and 197 +/- 63 g with consumption of AB, BBC, BBP, and VFB, respectively; less intestinal transit time; and significantly (P < 0.05) greater bowel movement frequency. Despite the increased activity of the bowel, a positive level of comfort was maintained. BBP was more effective than other cereals in terms of increasing fecal wet weight (P < 0.05). Water-insoluble dietary fibers (ie, AB and BBC) and their mixtures with water-soluble fibers (ie, BBP and VFB) in the form of breakfast cereals (2.5 servings/d) proved to be a practical way of increasing fiber intake to recommended levels, while maintaining a good level of tolerance.

A new method of fabricating a blend scaffold using an indirect three-dimensional printing technique.

PubMed

Jung, Jin Woo; Lee, Hyungseok; Hong, Jung Min; Park, Jeong Hun; Shim, Jung Hee; Choi, Tae Hyun; Cho, Dong-Woo

2015-11-03

Due to its simplicity and effectiveness, the physical blending of polymers is considered to be a practical strategy for developing a versatile scaffold having desirable mechanical and biochemical properties. In the present work, an indirect three-dimensional (i3D) printing technique was proposed to fabricate a 3D free-form scaffold using a blend of immiscible materials, such as polycaprolactone (PCL) and gelatin. The i3D printing technique includes 3D printing of a mold and a sacrificial molding process. PCL/chloroform and gelatin/water were physically mixed to prepare the blend solution, which was subsequently injected into the cavity of a 3D printed mold. After solvent removal and gelatin cross-linking, the mold was dissolved to obtain a PCL-gelatin (PG) scaffold, with a specific 3D structure. Scanning electron microscopy and Fourier transform infrared spectroscopy analysis indicated that PCL masses and gelatin fibers in the PG scaffold homogenously coexisted without chemical bonding. Compression tests confirmed that gelatin incorporation into the PCL enhanced its mechanical flexibility and softness, to the point of being suitable for soft-tissue engineering, as opposed to pure PCL. Human adipose-derived stem cells, cultured on a PG scaffold, exhibited enhanced in vitro chondrogenic differentiation and tissue formation, compared with those on a PCL scaffold. The i3D printing technique can be used to blend a variety of materials, facilitating 3D scaffold fabrication for specific tissue regeneration. Furthermore, this convenient and versatile technique may lead to wider application of 3D printing in tissue engineering.

[Dietary fibers: current trends and health benefits in the metabolic syndrome and type 2 diabetes].

PubMed

Mello, Vanessa D de; Laaksonen, David E

2009-07-01

Dietary fiber may contribute to both the prevention and treatment of type 2 diabetes mellitus (T2DM). In epidemiological studies the intake of insoluble fiber, but not the intake of soluble fiber, has been inversely associated with the incidence of T2DM. In contrast, in postprandial studies, meals containing sufficiently quantities of beta-glucan, psyllium, or guar gum have decreased insulin and glucose responses in both healthy individuals and patients with T2DM. Diets enriched sufficiently in soluble fiber may also improve overall glycemic control in T2DM. Insoluble fiber has little effect on postprandial insulin and glucose responses. Fiber increases satiety. In some studies, insoluble fiber has been associated with less weight gain over time. Limited cross-sectional evidence suggests an inverse relationship between intake of cereal fiber and whole-grains and the prevalence of the metabolic syndrome. Although long-term data from trials focusing on specifically dietary fiber are lacking, meeting current recommendations for a minimum fiber intake of 25 g/d based on a diet rich in whole grains, fruits and legumes will probably decrease the risk of obesity, the metabolic syndrome and T2DM.

Fiber-utilizing capacity varies in Prevotella- versus Bacteroides-dominated gut microbiota.

PubMed

Chen, Tingting; Long, Wenmin; Zhang, Chenhong; Liu, Shuang; Zhao, Liping; Hamaker, Bruce R

2017-06-01

The gut microbiota of individuals are dominated by different fiber-utilizing bacteria, which ferment dietary fiber into short chain fatty acids (SCFAs) known to be important for human health. Here, we show that the dominance of Prevotella versus Bacteroides in fecal innocula, identified into two different enterotypes, differentially impacts in vitro fermentation profiles of SCFAs from fibers with different chemical structures. In a microbiome of the Prevotella enterotype, fructooligosaccharides, and sorghum and corn arabinoxylans significantly promoted one single Prevotella OTU with equally high production of total SCFAs with propionate as the major product. Conversely, in the Bacteroides-dominated microbiota, the three fibers enriched different OTUs leading to different levels and ratios of SCFAs. This is the first report showing how individual differences in two enterotypes cause distinctly different responses to dietary fiber. Microbiota dominated by different fiber-utilizing bacteria may impact host health by way of producing different amounts and profiles of SCFAs from the same carbohydrate substrates.

Development and Characterization of Polymer Eco-Composites Based on Natural Rubber Reinforced with Natural Fibers.

PubMed

Stelescu, Maria-Daniela; Manaila, Elena; Craciun, Gabriela; Chirila, Corina

2017-07-11

Natural rubber composites filled with short natural fibers (flax and sawdust) were prepared by blending procedure and the elastomer cross-linking was carried out using benzoyl peroxide. The microbial degradation of composites was carried out by incubating with Aspergillus niger recognized for the ability to grow and degrade a broad range of substrates. The extent of biodegradation was evaluated by weight loss and cross-linking degree study of composites after 2 months incubation in pure shake culture conditions. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) have proved to be precious and valuable instruments for morphological as well as structural characterization of the composites before and after incubation with Aspergillus niger .

Development and Characterization of Polymer Eco-Composites Based on Natural Rubber Reinforced with Natural Fibers

PubMed Central

Stelescu, Maria-Daniela; Manaila, Elena; Craciun, Gabriela; Chirila, Corina

2017-01-01

Natural rubber composites filled with short natural fibers (flax and sawdust) were prepared by blending procedure and the elastomer cross-linking was carried out using benzoyl peroxide. The microbial degradation of composites was carried out by incubating with Aspergillus niger recognized for the ability to grow and degrade a broad range of substrates. The extent of biodegradation was evaluated by weight loss and cross-linking degree study of composites after 2 months incubation in pure shake culture conditions. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) have proved to be precious and valuable instruments for morphological as well as structural characterization of the composites before and after incubation with Aspergillus niger. PMID:28773145

Intercalated graphite fiber composites as EMI shields in aerospace structures

NASA Technical Reports Server (NTRS)

Gaier, James R.

1990-01-01

The requirements for electromagnetic interference (EMI) shielding in aerospace structures are complicated over that of ground structures by their weight limitations. As a result, the best EMI shielding materials must blend low density, high strength, and high elastic modulus with high shielding ability. In addition, fabrication considerations including penetrations and joints play a major role. The EMI shielding properties are calculated for shields formed from pristine and intercalated graphite fiber/epoxy composites and compared to preliminary experimental results and to shields made from aluminum. Calculations indicate that EMI shields could be fabricated from intercalated graphite composites which would have less than 12 percent of the mass of conventional aluminum shields, based on mechanical properties and shielding properties alone.

Multimodal nonlinear microscope based on a compact fiber-format laser source

NASA Astrophysics Data System (ADS)

Crisafi, Francesco; Kumar, Vikas; Perri, Antonio; Marangoni, Marco; Cerullo, Giulio; Polli, Dario

2018-01-01

We present a multimodal non-linear optical (NLO) laser-scanning microscope, based on a compact fiber-format excitation laser and integrating coherent anti-Stokes Raman scattering (CARS), stimulated Raman scattering (SRS) and two-photon-excitation fluorescence (TPEF) on a single platform. We demonstrate its capabilities in simultaneously acquiring CARS and SRS images of a blend of 6-μm poly(methyl methacrylate) beads and 3-μm polystyrene beads. We then apply it to visualize cell walls and chloroplast of an unprocessed fresh leaf of Elodea aquatic plant via SRS and TPEF modalities, respectively. The presented NLO microscope, developed in house using off-the-shelf components, offers full accessibility to the optical path and ensures its easy re-configurability and flexibility.

Comparative Study of the Physical, Topographical and Biological Properties of Electrospinning PCL, PLLA, their Blend and Copolymer Scaffolds

NASA Astrophysics Data System (ADS)

Bolbasov, E.; Goreninskii, S.; Tverdokhlebov, S.; Mishanin, A.; Viknianshchuk, A.; Bezuidenhout, D.; Golovkin, A.

2018-05-01

Biodegradable polymers (blends, copolymers) could be the ideal materials for manufacturing of scaffolds for small diameter vascular graft. Such material characteristics as mechanical properties, chemical structure, nano- and micro topography, surface charge, porosity, wettability etc. are becoming the most important aspects for effectiveness of prosthesis biofunctionalization because of their great impact on cell adhesion, spreading, cell proliferation, differentiation and cell function. The aim of the study is to compare physical, topographical and biological properties of polycaprolactone (PCL), poly-L-lactic acid (PLLA), polycaprolactone + poly-L-lactic acid blend (PCL PLLA), L-lactide/Caprolactone copolymer (PLC7015) scaffolds fabricated with the same fiber thickness using electrospun technology. PCL PLLA scaffolds had the highest average pore area (p<0.01) and the lowest strength (p<0.01). PLC7015 scaffolds had the significantly lower average pore area (p=0.03) but the highest elastic deformation (p<0.01). Biological testing with MMSC (multipotent mesenchyme stem cells) demonstrated that after 72 hours of co-cultivation only on PCL and PLLA scaffolds cells entered to the active phase of adhesion process. We propose that physical and topographical properties of PCL, PLLA, their blend and copolymer are of a great dependence of chemical structure but could be changed during the manufacturing process that will lead to changes in biological properties.

Effects of Dietary Fiber and Its Components on Metabolic Health

PubMed Central

Lattimer, James M.; Haub, Mark D.

2010-01-01

Dietary fiber and whole grains contain a unique blend of bioactive components including resistant starches, vitamins, minerals, phytochemicals and antioxidants. As a result, research regarding their potential health benefits has received considerable attention in the last several decades. Epidemiological and clinical studies demonstrate that intake of dietary fiber and whole grain is inversely related to obesity, type two diabetes, cancer and cardiovascular disease (CVD). Defining dietary fiber is a divergent process and is dependent on both nutrition and analytical concepts. The most common and accepted definition is based on nutritional physiology. Generally speaking, dietary fiber is the edible parts of plants, or similar carbohydrates, that are resistant to digestion and absorption in the small intestine. Dietary fiber can be separated into many different fractions. Recent research has begun to isolate these components and determine if increasing their levels in a diet is beneficial to human health. These fractions include arabinoxylan, inulin, pectin, bran, cellulose, β-glucan and resistant starch. The study of these components may give us a better understanding of how and why dietary fiber may decrease the risk for certain diseases. The mechanisms behind the reported effects of dietary fiber on metabolic health are not well established. It is speculated to be a result of changes in intestinal viscosity, nutrient absorption, rate of passage, production of short chain fatty acids and production of gut hormones. Given the inconsistencies reported between studies this review will examine the most up to date data concerning dietary fiber and its effects on metabolic health. PMID:22254008

Evaluation of 165 deg F reverse osmosis modules for washwater purification.

NASA Technical Reports Server (NTRS)

Hossain, S.; Goldsmith, R. L.; Tan, M.; Wydeven, T.; Leban, M. I.

1973-01-01

Three membrane systems have been evaluated for concentration at 165 F of wash-water contaminants. Membranes tested are polybenzimidazole (hollow fibers), cellulose acetate blend (spiral wound), and sulfonated polyphenylene oxide (plate-and-frame). Detailed membrane flux and rejection data are presented for 200-hr life tests with synthetic wash water, at two concentrations, and real wash water, at one concentration. Advantages and limitations of the membrane configurations, are discussed.

Improved Moisture Resistance of Fiber-Reinforced Plastic

DTIC Science & Technology

1981-12-01

molecular structure 21 1 Although there are some complicativ"-c, most researchers agree, water primarily degrades the fiberglass-matrix int~ rf -ace...H.W. Yip and J.B. Shortall, J. Adhesion, 8, 155 (1976). 25. J.A. Manson and H. Sperling, "Polymer Blends and Composites", "N.Y., 1978, p. 62. 26...Center, Sherwin- Williams Co. 10909 S. Cottage Grove, Chicago, IL 60628 iA .. . . . .- ..... 52 SPECTROSCOPIC CHARACTERIZATION OF THE MATRIX-SILANE

[INFLUENCE OF THE NUTRITIONAL COMPOSITION OF DIFFERENT FIBER-ENRICHED ENTERAL NUTRITION FORMULAS ON THE ADMINISTRATION TIME BY GRAVITY AND THE RISK OF TUBE FEEDING OBSTRUCTION].

PubMed

Bonada Sanjaume, Anna; Gils Contreras, Anna; Salas-Salvadó, Jordi

2015-08-01

the administration of enteral nutrition by gravity is a very useful method in clinical practice; nevertheless, it may not be very precise. Indeed, this method presents some important limitations, such as the difficulty in establishing a precise dripping rate and the possibility for the dripping rate decrease depending on the formula. assess the administration time and the risk of clogging of 5 fiber-enriched enteral nutrition formulas with different protein concentrations and caloric density, all administered by gravity through nasogastric (NG) tubes of different sizes. Assess the influence of the composition on the dripping rate, by gravity, of the tested formulas. 5 fiber-enriched EN formulas were compared by using nasogastric tubes of the calibers 8, 10 and 12 Fr. The fluidity of these gravity-administered NE formulas was estimated by timing the complete passage of each formula at full speed, thus allowing one to calculate the mean time of free fall (MTFF) and to register any possible obstruction. Subsequently, an in vitro simulation of a 1 500 ml administration was performed for each formula at a particular speed, so that the administration time was 5 hours. Slowing flow and stagnated flow were detected as indicators of the risk of obstruction. the two products that especially differed in MTFF were the ones with the highest energy concentration. The passage time in free fall of these two products through the 8 Fr tube exceeded four hours. For the rest of the products and NG tubes used, this time was less than 2 hours and 5 minutes. No slowing flow or tube obstruction was detected in free fall and at maximum speed. When the dripping was adjusted to be administered in 5 hours, three of the studied products (those with the least caloric concentration and viscosity) showed slowing flow and, in some cases, the dripping stopped completely. The most important factor associated to the MTFF was the lipid content, followed by viscosity, energy and protein content. The MTFF measured was not significantly related to the fiber content of the nutritional formula. all studied products can be administered by gravity via nasogastric tubes in free fall without any risk of obstruction, even though the free fall time was very variable. The lowest caliber tubes, the highest energy content and the viscosity of the EN mixture turn-out to be the limiting factors when fiber-enriched formulas are to be administered by gravity. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

In Vitro Degradation and Fermentation of Three Dietary Fiber Sources by Human Colonic Bacteria

PubMed Central

Bliss, Donna Z.; Weimer, Paul J.; Jung, Hans-Joachim G.; Savik, Kay

2013-01-01

Although clinical benefits of dietary fiber supplementation seem to depend partially on the extent of fiber degradation and fermentation by colonic bacteria, little is known about the effect of supplemental fiber type on bacterial metabolism. In an experiment using a non-adapted human bacterial population from three normal subjects, extent of in vitro fermentation was greater for gum arabic (GA) than for psyllium (PSY), which was greater than that for carboxymethylcellulose (CMC). In a separate experiment, in vitro incubation with feces from 52 subjects with fecal incontinence, before and after random assignment to and consumption of one of three fiber (GA, PSY, or CMC) supplements or a placebo for 20-21d, indicated that prior consumption of a specific fiber source did not increase its degradation by fecal bacteria. Results suggest that the colonic microbial community enriched on a particular fiber substrate can rapidly adapt to the presentation of a new fiber substrate. Clinical implications of the findings are that intake of a fiber source by humans is not expected to result in bacterial adaptation that would require continually larger and eventually intolerable amounts of fiber to achieve therapeutic benefits. PMID:23556460

In vitro degradation and fermentation of three dietary fiber sources by human colonic bacteria.

PubMed

Bliss, Donna Z; Weimer, Paul J; Jung, Hans-Joachim G; Savik, Kay

2013-05-15

Although clinical benefits of dietary fiber supplementation seem to depend partially on the extent of fiber degradation and fermentation by colonic bacteria, little is known about the effect of supplemental fiber type on bacterial metabolism. In an experiment using a nonadapted human bacterial population from three normal subjects, the extent of in vitro fermentation was greater for gum arabic (GA) than for psyllium (PSY), which was greater than that for carboxymethylcellulose (CMC). In a separate experiment, in vitro incubation with feces from 52 subjects with fecal incontinence, before and after random assignment to and consumption of one of three fiber (GA, PSY, or CMC) supplements or a placebo for 20-21 days, indicated that prior consumption of a specific fiber source did not increase its degradation by fecal bacteria. Results suggest that the colonic microbial community enriched on a particular fiber substrate can rapidly adapt to the presentation of a new fiber substrate. Clinical implications of the findings are that intake of a fiber source by humans is not expected to result in bacterial adaptation that would require continually larger and eventually intolerable amounts of fiber to achieve therapeutic benefits.

From microalgae oil to produce novel structured triacylglycerols enriched with unsaturated fatty acids.

PubMed

Wang, Jun; Wang, Xu-Dong; Zhao, Xing-Yu; Liu, Xi; Dong, Tao; Wu, Fu-An

2015-05-01

Novel structured triacylglycerols (STAGs) enriched with unsaturated fatty acids (UFAs) and low palmitic acid (PA) content were firstly synthesized from Schizochytrium sp. oil and oleic acid (OA) via solvent-free acidolysis catalyzed by Lipozyme RM IM. The results indicated that, the PA content decreased from 24.49% to 6.95%, while the UFAs content increased from 70.20% to 90.9% at the sn-1,3 positions in the STAGs under the optimal condition (i.e., lipase load of 7%, molar ratio of microalgae oil TAGs to OA of 1:3, and temperature of 65 °C). The lipase Lipozyme RM IM could be reused 16 times without significant loss of activity. The improved plastic and storage ranges of STAGs are useful for infant formula formulations, by which a possible method is blending of this product and 1,3-dioleoyl-2-palmitoylglycerol enriched fats and minor lipids based on the corresponding chemical compositions of human milk fat. Copyright © 2014 Elsevier Ltd. All rights reserved.

Tactile stimulation partially prevents neurodevelopmental changes in visual tract caused by early iron deficiency.

PubMed

Horiquini-Barbosa, Everton; Gibb, Robbin; Kolb, Bryan; Bray, Douglas; Lachat, Joao-Jose

2017-02-15

Iron deficiency has a critical impact on maturational mechanisms of the brain and the damage related to neuroanatomical parameters is not satisfactorily reversed after iron replacement. However, emerging evidence suggest that enriched early experience may offer great therapeutic efficacy in cases of nutritional disorders postnatally, since the brain is remarkably responsive to its interaction with the environment. Given the fact that tactile stimulation (TS) treatment has been previously shown to be an effective therapeutic approach and with potential application to humans, here we ask whether exposure to TS treatment, from postnatal day (P) 1 to P32 for 3min/day, could also be employed to prevent neuroanatomical changes in the optic nerve of rats maintained on an iron-deficient diet during brain development. We found that iron deficiency changed astrocyte, oligodendrocyte, damaged fiber, and myelinated fiber density, however, TS reversed the iron-deficiency-induced alteration in oligodendrocyte, damaged fiber and myelinated fiber density, but failed to reverse astrocyte density. Our results suggest that early iron deficiency may act by disrupting the timing of key steps in visual system development thereby modifying the normal progression of optic nerve maturation. However, optic nerve development is sensitive to enriching experiences, and in the current study we show that this sensitivity can be used to prevent damage from postnatal iron deficiency during the critical period. Copyright © 2016 Elsevier B.V. All rights reserved.

Segregation and inhomogeneities in photorefractive SBN fibers

NASA Astrophysics Data System (ADS)

Erdei, Sandor; Galambos, Ludwig; Tanaka, Isao; Hesselink, Lambertus; Ainger, Frank W.; Cross, Leslie E.; Feigelson, Robert S.

1996-10-01

Ce doped and undoped SrxBa1-xNb2O6 (SBN) fibers grown by the laser heated pedestal growth (LHPG) technique in Stanford University were investigated by 2D scanning electron microprobe analysis. The SBN fibers grown along c [001] or a [100] axes often show radially distributed optical inhomogeneities (core effects) of varying magnitude. Ba enrichment and Sr reduction were primarily detected in the core which can be qualitatively described by a complex-segregation effect. This defect structure as a complex-congruency related phenomenon modified by the composition-control mechanism of LHPG system. Its radial dependence of effective segregation coefficient is described by the modified Burton-Prim- Slichter equation.

Anti-biofouling 3D porous systems: the blend effect of oxazoline-based oligomers on chitosan scaffolds.

PubMed

Correia, Vanessa G; Coelho, Margarida; Barroso, Telma; Raje, Vivek P; Bonifácio, Vasco D B; Casimiro, Teresa; Pinho, Mariana G; Aguiar-Ricardo, Ana

2013-01-01

The production, characterization and anti-biofouling activity of 3D porous scaffolds combining different blends of chitosan and oxazoline-based antimicrobial oligomers is reported. The incorporation of ammonium quaternized oligo(2-oxazoline)s into the composition of the scaffold enhances the stability of the chitosan scaffold under physiological conditions as well as its ability to repel protein adsorption. The blended scaffolds showed mean pore sizes in the range of 18-32 μm, a good pore interconnectivity and high porosity, as well as a large surface area, ultimate key features for anti-biofouling applications. Bovine serum albumin (BSA) adhesion profiles showed that the composition of the scaffolds plays a critical role in the chitosan-oligooxazoline system. Oligobisoxazoline-enriched scaffolds (20% w/w, CB8020) decreased protein adsorption (BSA) by up to 70%. Moreover, 1 mg of CB8020 was able to kill 99.9% of Escherichia coli cells upon contact, demonstrating its potential as promising material for production of tailored non-fouling 3D structures to be used in the construction of novel devices with applications in the biomedical field and water treatment processes.

Chitin butyrate coated electrospun nylon-6 fibers for biomedical applications

NASA Astrophysics Data System (ADS)

Pant, Hem Raj; Kim, Han Joo; Bhatt, Lok Ranjan; Joshi, Mahesh Kumar; Kim, Eun Kyo; Kim, Jeong In; Abdal-hay, Abdalla; Hui, K. S.; Kim, Cheol Sang

2013-11-01

In this study, we describe the preparation and characterizations of chitin butyrate (CB) coated nylon-6 nanofibers using single-spinneret electrospinning of blends solution. The physicochemical properties of nylon-6 composite fibers with different proportions of CB to nylon-6 were determined using FE-SEM, TEM, FT-IR spectroscopy, and water contact angle measurement. FE-SEM and TEM images revealed that the nylon-6 and CB were immiscible in the as-spun nanofibers, and phase separated nanofiber morphology becomes more pronounced with increasing amounts of CB. The bone formation ability of composite fibers was evaluated by incubating in biomimetic simulated body fluid. In order to assay the cytocompatibility and cell behavior on the composite scaffolds, osteoblast cells were seeded on the matrix. Results suggest that the deposition of CB layer on the surface of nylon-6 could increase its cell compatibility and bone formation ability. Therefore, as-synthesized nanocomposite fibrous mat has great potentiality in hard tissue engineering.

Tunable Physical Properties of Ethylcellulose/Gelatin Composite Nanofibers by Electrospinning.

PubMed

Liu, Yuyu; Deng, Lingli; Zhang, Cen; Feng, Fengqin; Zhang, Hui

2018-02-28

In this work, the ethylcellulose/gelatin blends at various weight ratios in water/ethanol/acetic acid solution were electrospun to fabricate nanofibers with tunable physical properties. The solution compatibility was predicted based on Hansen solubility parameters and evaluated by rheological measurements. The physical properties were characterized by scanning electron microscopy, porosity, differential scanning calorimetry, thermogravimetry, Fourier transform infrared spectroscopy, and water contact angle. Results showed that the entangled structures among ethylcellulose and gelatin chains through hydrogen bonds gave rise to a fine morphology of the composite fibers with improved thermal stability. The fibers with higher gelatin ratio (75%), possessed hydrophilic surface (water contact angle of 53.5°), and adequate water uptake ability (1234.14%), while the fibers with higher ethylcellulose proportion (75%) tended to be highly water stable with a hydrophobic surface (water contact angle of 129.7°). This work suggested that the composite ethylcellulose/gelatin nanofibers with tunable physical properties have potentials as materials for bioactive encapsulation, food packaging, and filtration applications.

Interface Bond Improvement of Sisal Fibre Reinforced Polylactide Composites with Added Epoxy Oligomer

PubMed Central

Hao, Mingyang; Qiu, Feng; Wang, Xiwen

2018-01-01

To improve the interfacial bonding of sisal fiber-reinforced polylactide biocomposites, polylactide (PLA) and sisal fibers (SF) were melt-blended to fabricate bio-based composites via in situ reactive interfacial compatibilization with addition of a commercial grade epoxy-functionalized oligomer Joncryl ADR@-4368 (ADR). The FTIR (Fourier Transform infrared spectroscopy) analysis and SEM (scanning electron microscope) characterization demonstrated that the PLA molecular chain was bonded to the fiber surface and the epoxy-functionalized oligomer played a hinge-like role between the sisal fibers and the PLA matrix, which resulted in improved interfacial adhesion between the fibers and the PLA matrix. The interfacial reaction and microstructures of composites were further investigated by thermal and rheological analyses, which indicated that the mobility of the PLA molecular chain in composites was restricted because of the introduction of the ADR oligomer, which in turn reflected the improved interfacial interaction between SF and the PLA matrix. These results were further justified with the calculation of activation energies of glass transition relaxation (∆Ea) by dynamic mechanical analysis. The mechanical properties of PLA/SF composites were simultaneously reinforced and toughened with the addition of ADR oligomer. The interfacial interaction and structure–properties relationship of the composites are the key points of this study. PMID:29518949

Interface Bond Improvement of Sisal Fibre Reinforced Polylactide Composites with Added Epoxy Oligomer.

PubMed

Hao, Mingyang; Wu, Hongwu; Qiu, Feng; Wang, Xiwen

2018-03-07

To improve the interfacial bonding of sisal fiber-reinforced polylactide biocomposites, polylactide (PLA) and sisal fibers (SF) were melt-blended to fabricate bio-based composites via in situ reactive interfacial compatibilization with addition of a commercial grade epoxy-functionalized oligomer Joncryl ADR @ -4368 (ADR). The FTIR (Fourier Transform infrared spectroscopy) analysis and SEM (scanning electron microscope) characterization demonstrated that the PLA molecular chain was bonded to the fiber surface and the epoxy-functionalized oligomer played a hinge-like role between the sisal fibers and the PLA matrix, which resulted in improved interfacial adhesion between the fibers and the PLA matrix. The interfacial reaction and microstructures of composites were further investigated by thermal and rheological analyses, which indicated that the mobility of the PLA molecular chain in composites was restricted because of the introduction of the ADR oligomer, which in turn reflected the improved interfacial interaction between SF and the PLA matrix. These results were further justified with the calculation of activation energies of glass transition relaxation (∆ E a ) by dynamic mechanical analysis. The mechanical properties of PLA/SF composites were simultaneously reinforced and toughened with the addition of ADR oligomer. The interfacial interaction and structure-properties relationship of the composites are the key points of this study.

The Influence of Green Surface Modification of Oil Palm Mesocarp Fiber by Superheated Steam on the Mechanical Properties and Dimensional Stability of Oil Palm Mesocarp Fiber/Poly(butylene succinate) Biocomposite

PubMed Central

Then, Yoon Yee; Ibrahim, Nor Azowa; Zainuddin, Norhazlin; Ariffin, Hidayah; Yunus, Wan Md Zin Wan; Chieng, Buong Woei

2014-01-01

In this paper, superheated steam (SHS) was used as cost effective and green processing technique to modify oil palm mesocarp fiber (OPMF) for biocomposite applications. The purpose of this modification was to promote the adhesion between fiber and thermoplastic. The modification was carried out in a SHS oven at various temperature (200–230 °C) and time (30–120 min) under normal atmospheric pressure. The biocomposites from SHS-treated OPMFs and poly(butylene succinate) (PBS) at a weight ratio of 70:30 were prepared by melt blending technique. The mechanical properties and dimensional stability of the biocomposites were evaluated. This study showed that the SHS treatment increased the roughness of the fiber surface due to the removal of surface impurities and hemicellulose. The tensile, flexural and impact properties, as well as dimensional stability of the biocomposites were markedly enhanced by the presence of SHS-treated OPMF. Scanning electron microscopy analysis showed improvement of interfacial adhesion between PBS and SHS-treated OPMF. This work demonstrated that SHS could be used as an eco-friendly and sustainable processing method for modification of OPMF in biocomposite fabrication. PMID:25177865

Toxic emissions during co-combustion of biomass-waste wood-lignite blends in an industrial boiler.

PubMed

Samaras, P; Skodras, G; Sakellaropoulos, G P; Blumenstock, M; Schramm, K W; Kettrup, A

2001-01-01

The objectives of this work were to study the PCDD/F emissions during the co-combustion of waste wood/coal co-combustion in an industrial boiler and to determine the relation of the toxic emissions to the fuel properties. Co-combustion experiments were performed in a 13.8 MWthermal industrial moving grate combustor. The fuels which were examined in this study included Greek lignite, natural uncontaminated wood, power poles and medium density fibers (MDFs) which were by-products of the plant production process. Fuel blends were prepared by mixing single components in various concentrations. PCDD/F emissions were collected during experimental runs and were analyzed according to standard methods. Low PCDD/F emissions were obtained during the co-combustion tests, lower than the limit value of 0.1 ng TEQ/Nm3. The lowest values were observed during the combustion of fuel blends containing MDF, possibly due to the inhibitory action of some of the N-containing MDF ingredients, such as urea. No direct correlation was found between the PCDD/F and the copper emissions, while examination of the PCDD/F homologue patterns revealed the predominance of the lower chlorinated isomers over the higher ones.

Rheological, thermo-mechanical, and baking properties of wheat-millet flour blends.

PubMed

Aprodu, Iuliana; Banu, Iuliana

2015-07-01

Millet has long been known as a good source of fiber and antioxidants, but only lately started to be exploited by food scientists and food industry as a consequence of increased consumer awareness. In this study, doughs and breads were produced using millet flour in different ratios (10, 20, 30, 40, and 50%) to white, dark, and whole wheat flour. The flour blends were evaluated in terms of rheological and thermo-mechanical properties. Fundamental rheological measurements revealed that the viscosity of the flour formulations increases with wheat flour-extraction rate and decreases with the addition of millet flour. Doughs behavior during mixing, overmixing, pasting, and gelling was established using the Mixolab device. The results of this bread-making process simulation indicate that dough properties become critical for the flour blends with millet levels higher than 30%. The breads were evaluated for volume, texture, and crumb-grain characteristics. The baking test and sensory evaluation results indicated that substitution levels of up to 30% millet flour could be used in composite bread flour. High levels of millet flour (40 and 50%) negatively influenced the loaf volume, crumb texture, and taste. © The Author(s) 2014.

Genome-wide analysis of gene expression of EMS-induced short fiber mutant Ligon lintless-y (liy) in cotton (Gossypium hirsutum L.).

PubMed

Naoumkina, Marina; Bechere, Efrem; Fang, David D; Thyssen, Gregory N; Florane, Christopher B

2017-07-01

In this work we describe a chemically-induced short fiber mutant cotton line, Ligon-lintless-y (li y ), which is controlled by a single recessive locus and affects multiple traits, including height of the plant, and length and maturity of fiber. An RNAseq analysis was used to evaluate global transcriptional changes during cotton fiber development at 3, 8 and 16days post anthesis. We found that 613, 2629 and 3397 genes were significantly down-regulated, while 2700, 477 and 3260 were significantly up-regulated in li y at 3, 8 and 16 DPA. Gene set enrichment analysis revealed that many metabolic pathways, including carbohydrate, cell wall, hormone metabolism and transport were substantially altered in li y developing fibers. We discuss perturbed expression of genes involved in signal transduction and biosynthesis of phytohormones, such as auxin, abscisic acid, gibberellin and ethylene. The results of this study provide new insights into transcriptional regulation of cotton fiber development. Published by Elsevier Inc.

[Preparation of a novel activated carbon coating fiber for solid phase micro-extraction and its application for halocarbon compound analysis in water].

PubMed

Wang, Shutao; Wang, Yan; You, Hong; Liang, Zhihua

2004-09-01

A novel activated carbon coating fiber used for solid phase micro-extraction (SPME) was prepared using activated carbon powder and silica resin adhesive. The extraction properties of the novel activated carbon coating fiber were investigated. The results indicate that this coating fiber has high concentration ability, with enrichment factors for chloroform, carbon tetrachloride, trichloroethylene and tetrachloroethylene in the range of 13.8 to 18.7. The fiber is stable at temperature as high as 290 degrees C and it can be used for over 140 times at 250 degrees C. The activated carbon coating fiber was then applied to the analysis of the four halocarbon compounds mentioned above. A linear correlation with correlation coefficients between 0.995 2 and 0.999 4 and the detection limits between 0.008 and 0.05 microg/L were observed. The method was also applied to a real water sample analysis and the recoveries of these halocarbon compounds were from 95.5% to 104.6%.

Effects of help-seeking in a blended high school Biology class

NASA Astrophysics Data System (ADS)

Deguzman, Paolo

Distance learning provides an opportunity for students to learn valuable information through technology and interactive media. Distance learning additionally offers educational institutions the flexibility of synchronous and asynchronous instruction while increasing enrollment and lowering cost. However, distance education has not been well documented within the context of urban high schools. Distance learning may allow high school students to understand material at an individualized pace for either enrichment or remediation. A successful high school student who participates in distance learning should exhibit high self regulatory skills. However, most urban high school students have not been exposed to distance learning and should be introduced to proper self regulatory strategies that should increase the likelihood of understanding the material. To help facilitate a move into distance learning, a blended distance learning model, the combination of distance learning and traditional learning, will be used. According to O'Neil's (in preparation) revised problem solving model, self regulation is a component of problem solving. Within the Blended Biology course, urban high school students will be trained in help-seeking strategies to further their understanding of genetics and Punnett Square problem solving. This study investigated the effects of help-seeking in a blended high school Biology course. The main study consisted of a help-seeking group (n=55) and a control group (n=53). Both the help-seeking group and the control group were taught by one teacher for two weeks. The help-seeking group had access to Blended Biology with Help-Seeking while the control group only had access to Blended Biology. The main study used a pretest and posttest to measure Genetics Content Understanding, Punnett Square Problem Solving, Adaptive Help-Seeking, Maladaptive Help-Seeking, and Self Regulation. The analysis showed no significant difference in any of the measures in terms of help seeking. However, blended distance learning appeared to work as posttest means increased significantly from the pretest means. Future studies should consider the method of communication for help-seeking and help-giving within a high school distance learning context. Further studies should consider developing instruments to measure the difference in knowing when help is needed versus active choice.

Putting Lives on the Line: The Fast Rope Glove Challenge

DTIC Science & Technology

2012-06-01

conductivity. They were 1) Silica Aerogel , 2) Silica/Ceramic NASA Q-Fiber and 3) Nomex/Kevlar. Silica Aerogel has the lowest thermal conductivity...of any known solid and was recently made into a viable material by the company Aspen Aerogel .3 The other materials have lower conductivity than the...blend and a silica aerogel pad that could be incorporated into the palms and finger pads of the glove. For this evaluation, we tested: • The Superior

Influence of processing sequence on the tribological properties of VGCF-X/PA6/SEBS composites

NASA Astrophysics Data System (ADS)

Osada, Yu; Nishitani, Yosuke; Kitano, Takeshi

2016-03-01

In order to develop the new tribomaterials for mechanical sliding parts with sufficient balance of mechanical and tribological properties, we investigated the influence of processing sequence on the tribological properties of the ternary nanocomposites: the polymer blends of polyamide 6 (PA6) and styrene-ethylene/butylene-styrene copolymer (SEBS) filled with vapor grown carbon fiber (VGCF-X), which is one of carbon nanofiber (CNF) and has 15nm diameter and 3μm length. Five different processing sequences: (1) VGCF-X, PA6 and SEBS were mixed simultaneously (Process A), (2) Re-mixing (Second compounding) of the materials prepared by Process A (Process AR),(3) SEBS was blended with PA6 (PA6/SEBS blends) and then these blends were mixed with VGCF-X (Process B), (4) VGCF-X was mixed with PA6 (VGCF-X/PA6 composites) and then these composites were blended with SEBS (Process C), and (5) VGCF-X were mixed with SEBS (VGCF-X/SEBS composites) and then these composites were blended with PA6 (Process D) were attempted for preparing of the ternary nanocomposites (VGCF-X/PA6/SEBS composites). These ternary polymer nanocomposites were extruded by a twin screw extruder and injection-molded. Their tribological properties were evaluated by using a ring-on-plate type sliding wear tester under dry condition. The tribological properties such as the frictional coefficient and the specific wear rate were influenced by the processing sequence. These results may be attributed to the change of internal structure formation, which is a dispersibility of SEBS particle and VGCF-X in ternary nanocomposites (VGCF-X/PA6/SEBS) by different processing sequences. In particular, the processing sequences of AR, B and D, which are those of re-mixing of VGCF-X, have a good dispersibility of VGCF-X for the improvement of tribological properties.

Cytotoxicity of blended versus single medicinal mushroom extracts on human cancer cell lines: contribution of polyphenol and polysaccharide content.

PubMed

Durgo, Ksenija; Koncar, Mladen; Komes, Drazenka; Belscak-Cvitanovic, Ana; Franekic, Jasna; Jakopovich, Ivan; Jakopovich, Neven; Jakopovich, Boris

2013-01-01

The use of mushrooms contributes to human nutrition by providing low lipid content of lipids and high dietary fiber content, as well as significant content of other biologically active compounds such as polysaccharides, minerals, vitamins, and polyphenolic antioxidants. This study aimed to determine the content of polyphenols and polysaccharides, as well as the cytotoxic and antioxidative properties of several medicinal mushroom preparations. The content of total phenols and flavonoids of preparations of blended mushroom extracts (Lentifom, Super Polyporin, Agarikon, Agarikon Plus, Agarikon.1, and Mykoprotect.1) was evaluated quantitatively by using ultraviolet-visible spectroscopy spectrophotometric methods. The antioxidant capacity of the preparations was evaluated using the ABTS (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) and ferric reducing/antioxidant power assays. The content of water-soluble polysaccharides was determined using a specific gravimetric method, based on ethanol precipitation. To determine cytotoxic effects of single and blended mushroom extracts, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and neutral red assays were conducted using human small cell lung cancer, lung adenocarcinoma, colon cancer, and brain astrocytoma cancer cells. The obtained results suggest that due to the significant content of beneficial polyphenolic antioxidants and soluble polysaccharides, use of these mushroom preparations is beneficial in maintaining good health, as well as in the prevention and adjuvant biotherapy of various human pathological aberrations. These results reveal that these extracts exhibit different cytotoxic effects on tumor cells originating from different tissues. In addition, the comparison of investigated blended mushroom extracts with three well-known commercial mushroom products derived from single mushroom species or single mushroom compounds shows that blended mushroom extracts exhibit significantly stronger cytotoxic effects on human tumor cell lines.

Polymer blend of PLA/PHBV based bionanocomposites reinforced with nanocrystalline cellulose for potential application as packaging material.

PubMed

Dasan, Y K; Bhat, A H; Ahmad, Faiz

2017-02-10

The current research discusses the development of poly (lactic acid) (PLA) and poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) reinforced nanocrystalline cellulose bionanocomposites. The nanocrystalline cellulose was derived from waste oil palm empty fruit bunch fiber by acid hydrolysis process. The resulting nanocrystalline cellulose suspension was then surface functionalized by TEMPO-mediated oxidation and solvent exchange process. Furthermore, the PLA/PHBV/nanocrystalline cellulose bionanocomposites were produced by solvent casting method. The effect of the addition of nanocrystalline cellulose on structural, morphology, mechanical and barrier properties of bionanocomposites was investigated. The results revealed that the developed bionanocomposites showed improved mechanical properties and decrease in oxygen permeability rate. Therefore, the developed bio-based composite incorporated with an optimal composition of nanocrystalline cellulose exhibits properties as compared to the polymer blend. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preparation and Mechanical Properties of Fiber Reinforced PLA for 3D Printing Materials

NASA Astrophysics Data System (ADS)

Li, Xionghao; Ni, Zhongjin; Bai, Shuyang; Lou, Baiyang

2018-03-01

The cellulose prepared by means of TEMPO oxidation method and glass fibre was blended with PLA respectively, and were spun into enhanced PLA wires. This study evaluates the wire rods that is from extruder is suitable for FDM printing by various physical characterization tests to determine their feasibility as a 3D printing filament materials. The cellulose and glass fibre is blended with PLA and spun into the reinforced PLA filament respectively, which is applied to FDM printing technology. The results showed that the intensity of strike resistant of the reinforced PLA filament made from cellulose and PLA is 34% to 60% higher than the PLA filament, meanwhile the tensile strength is 43% to 52% higher than the pure one. The other enhanced PLA filament is 13% to 35% higher than the PLA filament in intensity of strike resistant, and the tensile strength is 54% to 61% higher than the pure one.

Review of thermal properties of graphite composite materials

NASA Technical Reports Server (NTRS)

Kourtides, D. A.

1987-01-01

Flammability, thermal, and selected mechanical properties of composites fabricated with epoxy and other thermally stable resin matrices are described. Properties which were measured included limiting-oxygen index, smoke evolution, thermal degradation products, total-heat release, heat-release rates, mass loss, flame spread, ignition resistance, thermogravimetric analysis, and selected mechanical properties. The properties of 8 different graphite composite panels fabricated using four different resin matrices and two types of graphite reinforcement are described. The resin matrices included: XU71775/H795, a blend of vinyl polystyryl pyridine and bismaleimide; H795, a bismaleimide; Cycom 6162, a phenolic; and PSP 6022M, a polystyryl pyridine. The graphite fiber used was AS-4 in the form of either tape or fabric. The properties of these composites were compared with epoxy composites. It was determined that the blend of vinyl polystyryl pyridine and bismaleimide (XU71775/H795) with the graphite tape was the optimum design giving the lowest heat release rate.

Cardiac differentiation of cardiosphere-derived cells in scaffolds mimicking morphology of the cardiac extracellular matrix.

PubMed

Xu, Yanyi; Patnaik, Sourav; Guo, Xiaolei; Li, Zhenqing; Lo, Wilson; Butler, Ryan; Claude, Andrew; Liu, Zhenguo; Zhang, Ge; Liao, Jun; Anderson, Peter M; Guan, Jianjun

2014-08-01

Stem cell therapy has the potential to regenerate heart tissue after myocardial infarction (MI). The regeneration is dependent upon cardiac differentiation of the delivered stem cells. We hypothesized that timing of the stem cell delivery determines the extent of cardiac differentiation as cell differentiation is dependent on matrix properties such as biomechanics, structure and morphology, and these properties in cardiac extracellular matrix (ECM) continuously vary with time after MI. In order to elucidate the relationship between ECM properties and cardiac differentiation, we created an in vitro model based on ECM-mimicking fibers and a type of cardiac progenitor cell, cardiosphere-derived cells (CDCs). A simultaneous fiber electrospinning and cell electrospraying technique was utilized to fabricate constructs. By blending a highly soft hydrogel with a relatively stiff polyurethane and modulating fabrication parameters, tissue constructs with similar cell adhesion property but different global modulus, single fiber modulus, fiber density and fiber alignment were achieved. The CDCs remained alive within the constructs during a 1week culture period. CDC cardiac differentiation was dependent on the scaffold modulus, fiber volume fraction and fiber alignment. Two constructs with relatively low scaffold modulus, ∼50-60kPa, most significantly directed the CDC differentiation into mature cardiomyocytes as evidenced by gene expressions of cardiac troponin T (cTnT), calcium channel (CACNA1c) and cardiac myosin heavy chain (MYH6), and protein expressions of cardiac troponin I (cTnI) and connexin 43 (CX43). Of these two low-modulus constructs, the extent of differentiation was greater for lower fiber alignment and higher fiber volume fraction. These results suggest that cardiac ECM properties may have an effect on cardiac differentiation of delivered stem cells. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Impact of casein and egg white proteins on the structure of wheat gluten-based protein-rich food.

PubMed

Wouters, Arno G B; Rombouts, Ine; Lagrain, Bert; Delcour, Jan A

2016-02-01

There is a growing interest in texturally and nutritionally satisfying vegetable alternatives to meat. Wheat gluten proteins have unique functional properties but a poor nutritional value in comparison to animal proteins. This study investigated the potential of egg white and bovine milk casein with well-balanced amino acid composition to increase the quality of wheat gluten-based protein-rich foods. Heating a wheat gluten (51.4 g)-water (100.0 mL) blend for 120 min at 100 °C increased its firmness less than heating a wheat gluten (33.0 g)-freeze-dried egg white (16.8 g)-water (100.0 mL) blend. In contrast, the addition of casein to the gluten-water blend negatively impacted firmness after heating. Firmness was correlated with loss of protein extractability in sodium dodecyl sulfate containing medium during heating, which was higher with egg white than with casein. Even more, heat-induced polymerization of the gluten-water blend with egg white but not with casein was greater than expected from the losses in extractability of gluten and egg white on their own. Structure formation was favored by mixing gluten with egg white but not with casein. These observations were linked to the intrinsic polymerization behavior of egg white and casein, but also to their interaction with gluten. Thus not all nutritionally suitable proteins can be used for enrichment of gluten-based protein-rich foods. © 2015 Society of Chemical Industry.

The use of chitosan/PLA nano-fibers by emulsion eletrospinning for periodontal tissue engineering.

PubMed

Shen, Renze; Xu, Weihong; Xue, Yanxiang; Chen, Luyuan; Ye, Haicheng; Zhong, Enyi; Ye, Zhanchao; Gao, Jie; Yan, Yurong

2018-04-16

In this study, nanofibrous scaffolds base on pure polylactic acid (PLA) and chitosan/PLA blends were fabricated by emulsion eletrospinning. By modulating their mechanical and biological properties, cell-compatible and biodegradable scaffolds were developed for periodontal bone regeneration. Pure PLA and different weight ratios of chitosan nano-particle/PLA nano-fibers were fabricated by emulsion eletrospinning. Scanning electron microscope (SEM) was performed to observe the morphology of nano-fibers. Mechanical properties of nano-fibers were tested by single fiber strength tester. Hydrophilic/hydrophobic nature of the nano-fibers was observed by stereomicroscope. In vitro degradation was also tested. Cells were seeded on nano-fibers scaffolds. Changes in cell adhesion, proliferation and osteogenic differentiation were tested by MTT assay and Alizarin Red S staining. Reverse transcription-polymerase chain reaction (RT-PCR) assay was used to evaluate the expression of (Toll-like receptor 4) TLR4, IL-6, IL-8, IL-1β, OPG, RUNX2 mRNA. It is shown that the mean diameter of nano-fibers is about 200 nm. The mean diameter of chitosan nano-particles is about 50 nm. The combination of chitosan nano-particles enhanced the mechanical properties of pure PLA nano-fibers. By adding a certain amount of chitosan nano-particles, it promoted cell adhesion. It also promoted the osteogenic differentiation of bone marrow stem cells (BMSCs) by elevating the expression of osteogenic marker genes such as BSP, Ocn, collagen I, and OPN and enhanced ECM mineralization. Nonetheless, it caused higher expression of inflammatory mediators and TLR4 of human periodontal ligament cells (hPDLCs). The combination of chitosan nano-particles enhanced the mechanical properties of pure PLA nano-fibers and increased its hydrophilicity. Pure PLA nano-fibers scaffold facilitated BMSCs proliferation. Adding an appropriate amount of chitosan nano-particles may promote its properties of cell proliferation and osteogenic differentiation. The higher expression of inflammatory mediators caused by nano-fibers may be regulated via TLR4 pathway.

The Impact of Low Octane Hydrocarbon Blending Streams on Ethanol Engine Optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szybist, James P; West, Brian H

2013-01-01

Ethanol is a very attractive fuel from an end-use perspective because it has a high chemical octane number and a high latent heat of vaporization. When an engine is optimized to take advantage of these fuel properties, both efficiency and power can be increased through higher compression ratio, direct fuel injection, higher levels of boost, and a reduced need for enrichment to mitigate knock or protect the engine and aftertreatment system from overheating. The ASTM D5798 specification for high level ethanol blends, commonly called E85, underwent a major revision in 2011. The minimum ethanol content was revised downward from 68more » vol% to 51 vol%, which combined with the use of low octane blending streams such as natural gasoline introduces the possibility of a lower octane E85 fuel. While this fuel is suitable for current ethanol tolerant flex fuel vehicles, this study experimentally examines whether engines can still be aggressively optimized for the resultant fuel from the revised ASTM D5798 specification. The performance of six ethanol fuel blends, ranging from 51-85% ethanol, is compared to a premium-grade certification gasoline (UTG-96) in a single-cylinder direct-injection (DI) engine with a compression ratio of 12.9:1 at knock-prone engine conditions. UTG-96 (RON = 96.1), light straight run gasoline (RON = 63.6), and n-heptane (RON = 0) are used as the hydrocarbon blending streams for the ethanol-containing fuels in an effort to establish a broad range of knock resistance for high ethanol fuels. Results show that nearly all ethanol-containing fuels are more resistant to engine knock than UTG-96 (the only exception being the ethanol blend with 49% n-heptane). This knock resistance allows ethanol blends made with 33 and 49% light straight run gasoline, and 33% n-heptane to be operated at significantly more advanced combustion phasing for higher efficiency, as well as at higher engine loads. While experimental results show that the octane number of the hydrocarbon blend stock does impact engine performance, there remains a significant opportunity for engine optimization when considering even the lowest octane fuels that are in compliance with the current revision of ASTM D5798 compared to premium-grade gasoline.« less

Organoleptic properties and perception of maize, African yam bean, and defatted coconut flour-based breakfast cereals served in conventional forms.

PubMed

Usman, Grace Ojali; Okafor, Gabriel Ifeanyi

2016-09-01

Breakfast cereals were produced by roasting (t = 280°C) - a dry heat treatment process to gelatinize and semidextrinize the starch - in order to generate dry ready-to-eat products from blends of African yam bean (AYB), maize (M), and defatted coconut (DC) flour. Six samples were generated by mixing AYB and maize composite flour with graded levels of DC flour (0%, 10%, 20%, 30%, 40%, and 50%) to obtain the following ratios; 100:0, 90:10, 80:20, 70:30, 60:40, and 50:50 that were added equal quantities of sugar, salt, sorghum malt extract, and water. The obtained products were served dry (without added fluid), with water, milk, and warm milk to 15 panelists along with Weetabix Original (commercial control) to evaluate color, consistency, flavor, taste, aftertaste, mouth feel, and overall acceptability using a nine-point hedonic scale (1 = dislike extremely, 9 = like extremely). The results revealed that the samples were acceptable to the panelists. There were no significant (P > 0.05) differences, between the control (Weetabix) and the formulated samples in terms of overall acceptability, when served with water, whereas significant differences (P < 0.05) existed when served dry, with milk or warm milk. This new roasting process for producing breakfast cereals offers huge potentials for production of acceptable breakfast cereals enriched with protein and fiber-rich sources that could be consumed dry, with water, milk, or warm milk.

Electrospinning of doxorubicin loaded silica/poly(ɛ-caprolactone) hybrid fiber mats for sustained drug release

NASA Astrophysics Data System (ADS)

El Gohary, Mohammed I.; El Hady, Bothaina M. Abd; Saeed, Aziza A. Al; Tolba, Emad; El Rashedi, Ahlam M. I.; Saleh, Safaa

2018-06-01

Loading of anticancer drugs into electrospun fiber matrices is a portentous approach for clinical treatment of diseased tissues or organs. In this study, doxorubicin hydrochloride (DOX) is added to silica nanoparticles () during the formation of via the sol-gel approach. The obtained nanoparticles are then added to poly(-caprolactone) (PCL) and poly(ethylene oxide) (PEO) blend before electrospinning process via different methods. The effects of DOX addition as a free form or as nanoparticles on physical and chemical properties of obtained PCL-PEO fibers, as well as release profiles are evaluated to give a continual DOX release for several days. The morphology observed with scanning electron microscope (FESEM) revealed significant changes in the average diameter of obtained fibers ranging from 2164 nm to 659 nm and distribution of drug-loaded nanoparticles in the final mats according to the mode of additions. With the same manner, the releasing performances of obtained mats are quite different. Therefore, fabrication of drug loaded mats would offer a powerful approach to minimize serious side effects for clinical patients and allows us to control the drug concentration in the bloodstream.

Content of bioactive compounds and antioxidant capacity of pumpkin puree enriched with japanese quince, cornelian cherry, strawberry and apples.

PubMed

Nawirska-Olszańska, Agnieszka; Biesiada, Anita; Sokół-Łętowska, Anna; Kucharska, Alicja Z

2011-01-01

When evaluated in terms of taste, smell or active ingredients, pumpkin in itself is not very attractive as a raw material. Hence, it is recommended to blend pumpkin with other fruits, which are aromatic, have a defined taste, and contain a large quantity of active ingredients and organic acids to improve its palatibility. The pumpkin chosen for the experiments was of the variety Karowita, of species Cucurbita maxima. Ten different of compositions were prepared for the purpose of the study: 10, 20 and 30% (w/w) of Japanese quince and cornelian cherry each, or 20 and 30% (w/w) of strawberry and apple each. The puree was then analysed for dry matter, extract, viscosity, colour, vitamin C, total polyphenols, carotenoids and DPPH. The highest content of vitamin C, which was in direct proportion to the quantity of the supplement added (17.88 to 23.43 mg·100 g(-1)), was detected in the quince-enriched puree. The lowest vitamin C content was determined in apple-enriched samples (1.36 to 1.6 mg·100 g(-1)). A similar pattern was observed with total polyphenols: the highest values were measured in quince-enriched puree, and the lowest in the puree supplemented with apple. Taking into account antioxidant properties of the samples, quince-enriched pumpkin puree was found to be the most attractive, and apple-enriched pumpkin puree the least attractive one. The results suggest a wide range of application for pumpkin puree enriched with various additives.

The simultaneous generation of soliton bunches and Q-switched-like pulses in a partially mode-locked fiber laser with a graphene saturable absorber

NASA Astrophysics Data System (ADS)

Wang, Zhenhong; Wang, Zhi; Liu, Yan-ge; He, Ruijing; Wang, Guangdou; Yang, Guang; Han, Simeng

2018-05-01

We experimentally report the coexistence of soliton bunches and Q-switched-like pulses in a partially mode-locked fiber laser with a microfiber-based graphene saturable absorber. The soliton bunches, like isolated spikes with extreme amplitude and ultrashort duration, randomly generate in the background of the Q-switched-like pulses. The soliton bunches have some pulse envelopes in which pulses operate at a fundamental repetition rate in the temporal domain. Further investigation shows that the composite pulses are highly correlated with the noise-like pulses. Our work can make a further contribution to enrich the understanding of the nonlinear dynamics in fiber lasers.

Electrospun polycaprolactone/gelatin composites with enhanced cell-matrix interactions as blood vessel endothelial layer scaffolds.

PubMed

Jiang, Yong-Chao; Jiang, Lin; Huang, An; Wang, Xiao-Feng; Li, Qian; Turng, Lih-Sheng

2017-02-01

During the fabrication of tissue engineering scaffolds and subsequent tissue regeneration, surface bioactivity is vital for cell adhesion, spreading, and proliferation, especially for endothelium dysfunction repair. In this paper, synthetic polymer polycaprolactone (PCL) was blended with natural polymer gelatin at four different weight ratios followed by crosslinking (i.e., 100:0, 70:30, 50:50, 30:70, labeled as PCL-C, P7G3-C, P5G5-C, and P3G7-C) to impart enhanced bioactivity and tunable mechanical properties. The PCL/gelatin blends were first dissolved in 2,2,2-trifluroethanol (TFE) and supplementary acetic acid (1% relative to TFE) solvent, electrospun, and then cross-linked to produce PBS-proof fibrous scaffolds. Scanning electron micrographs (SEM) indicated that fibers of each sample were smooth and homogeneous, with the fiber diameters increasing from 1.01±0.51μm to 1.61±0.46μm as the content of gelatin increased. While thermal resistance and crystallization of the blends were affected by the presence of gelatin, as reflected by differential scanning calorimetry (DSC) results, water contact angle (WCA) tests confirmed that the scaffold surfaces became more hydrophilic. Tensile tests showed that PCL-C and P7G3-C scaffolds had mechanical properties comparable to those of human coronary arteries. As for cytocompatibility, skeleton staining images showed that human mesenchymal stem cells (hMSCs) had more favorable binding sites on PCL/gelatin scaffolds than those on PCL scaffolds. Cell proliferation assays revealed that P7G3-C scaffolds could support the most number of hMSCs. The results of this study demonstrated the enhanced cell-matrix interactions and potential use of electrospun PCL/gelatin scaffolds in the tissue engineering field, especially in wound dressings and endothelium regeneration. Copyright © 2016 Elsevier B.V. All rights reserved.

Rice Cakes Containing Dietary Fiber Supplemented with or without Artemisia Annua and Gynura Procumbens Merr. Alleviated the Risk Factors of Metabolic Syndrome.

PubMed

Yoon, Na Rae; Yoon, Sun; Lee, Seung-Min

2016-04-01

We investigated whether the consumption of Korean rice cakes enriched with dietary fiber with or without polyphenol rich plants might decrease the risk factors of metabolic syndrome (MetS). Rice cakes were manufactured using fructooligosaccharides, resistant starch, and psyllium as sources of dietary fibers with and without polyphenol rich Artemisia annua and Gynura procumbens Merr. (RC+FP and RC+F, respectively), and prepared in three forms (songpyeon, seolgidduk, and chaldduk). Ninety subjects with at least one MetS risk factor were recruited for 6 weeks of dietary intervention. Sixty subjects were finally included for the analysis. Compared to the initial values, RC+FP group had decreased levels of fasting blood glucose (FBG), HOMA-IR and blood pressure after 6 weeks, whereas RC+F group didn't have significant changes in them. Regarding the improvement of individual MetS risk factors, RC+FP group showed significant reduction in FBG and blood pressures but RC+F group only had reduction in systolic blood pressure. After the intervention, a reduction in the number of MetS risk factors was greatert in the RC+FP group than in the RC+F group. In conclusion, Dietary fiber enriched rice cakes with or without polyphenols decreased the number and/or the levels of MetS risk factors. Polyphenol rich plant components may provide additional health benefits in controlling FBG and blood pressure.

Rice Cakes Containing Dietary Fiber Supplemented with or without Artemisia Annua and Gynura Procumbens Merr. Alleviated the Risk Factors of Metabolic Syndrome

PubMed Central

2016-01-01

We investigated whether the consumption of Korean rice cakes enriched with dietary fiber with or without polyphenol rich plants might decrease the risk factors of metabolic syndrome (MetS). Rice cakes were manufactured using fructooligosaccharides, resistant starch, and psyllium as sources of dietary fibers with and without polyphenol rich Artemisia annua and Gynura procumbens Merr. (RC+FP and RC+F, respectively), and prepared in three forms (songpyeon, seolgidduk, and chaldduk). Ninety subjects with at least one MetS risk factor were recruited for 6 weeks of dietary intervention. Sixty subjects were finally included for the analysis. Compared to the initial values, RC+FP group had decreased levels of fasting blood glucose (FBG), HOMA-IR and blood pressure after 6 weeks, whereas RC+F group didn't have significant changes in them. Regarding the improvement of individual MetS risk factors, RC+FP group showed significant reduction in FBG and blood pressures but RC+F group only had reduction in systolic blood pressure. After the intervention, a reduction in the number of MetS risk factors was greatert in the RC+FP group than in the RC+F group. In conclusion, Dietary fiber enriched rice cakes with or without polyphenols decreased the number and/or the levels of MetS risk factors. Polyphenol rich plant components may provide additional health benefits in controlling FBG and blood pressure. PMID:27152297

Rapid determination of 54 pharmaceutical and personal care products in fish samples using microwave-assisted extraction-Hollow fiber-Liquid/solid phase microextraction.

PubMed

Zhang, Yi; Guo, Wen; Yue, Zhenfeng; Lin, Li; Zhao, Fengjuan; Chen, Peijin; Wu, Weidong; Zhu, Hong; Yang, Bo; Kuang, Yanyun; Wang, Jiong

2017-04-15

In this paper, a simple, rapid, solvent-less and environmental friendliness microextraction method, microwave-assisted extraction-hollow fiber-liquid/solid phase microextraction (MAE-HF-L/SME), was developed for simultaneous extraction and enrichment of 54 trace hydrophilic/lipophilic pharmaceutical and personal care products (PPCPs) from fish samples. A solid-phase extraction material, solid-phase microextraction (SPME) fiber, was synthesized. The SPME fiber had a homogeneous, loose structure and good mechanical properties, and they exhibited a good adsorption capacity for most PPCPs selected. The material formed the basis for the method of MAE-HF-L/SME. A method of liquid chromatography-high resolution mass spectroscopy (LC-HRMS) for analysis of 54 PPCPs. Under optimal synthesis and extraction conditions, the limits of detection (LODs, n=3) and the limits of quantitation (LOQs, n=10) for the 54 PPCPs were between 0.01-0.50μg·kg -1 and 0.052.00μg·kg -1 , respectively. Percent recoveries and the relative standard deviations (RSDs) in spiked fish samples (n=6) were between 56.3%-119.9% and 0.3%-17.1%, respectively. The microextraction process of 54 PPCPs in MAE-HF-L/SME took approximately 12min. The method has a low matrix interference and high enrichment factor and may be applicable for determination of 54 different PPCPs in fish samples. Copyright © 2017 Elsevier B.V. All rights reserved.

α-synuclein expression in the mouse cerebellum is restricted to VGluT1 excitatory terminals and is enriched in unipolar brush cells

PubMed Central

Lee, Sun Kyong; Sillitoe, Roy V.; Silva, Coralie; Martina, Marco; Sekerkova, Gabriella

2015-01-01

α-synuclein has a crucial role in synaptic vesicle release and synaptic membrane recycling. Although its general expression pattern has been described in the cerebellum, the precise cerebellar structures where α-synuclein is localized are poorly understood. To address this question, we used α-synuclein immunohistochemistry in adult mice cerebellar sections. We found that α-synuclein labels glutamatergic but not glycinergic and GABAergic synaptic terminals in the molecular and granule cell layers. α-synuclein was preferentially expressed in parallel and mossy fiber synaptic terminals that also express vesicular glutamate transporter 1 (VGluT1) while it was not detected in VGluT2-positive climbing fibers. α-synuclein was particularly enriched in lobules IX and X, a region known to contain high density of unipolar brush cells (UBCs). To elucidate whether the α-synuclein-positive mossy fibers belong to UBCs, we double labeled cerebellar sections with antibodies to α-synuclein and UBCs type specific markers(calretinin for type I and metabotropic glutamate receptor 1α (mGluR1α) for type II UBCs), and took advantage of organotypic cerebellar cultures (in which all mossy fibers are UBC axons) and moonwalker mice (in which almost all UBCs are ablated) and found that both type I and type II UBCs express α-synuclein. In moonwalker mutant cerebella, the α-synuclein/VGluT1 immunolabeling showed dramatic decrease in the vestibulocerebellum that correlated with the absence of UBC. α-synuclein appears to be an excellent marker for intrinsic mossy fibers of the VGluT1 subset in conjunction with UBCs of both subtypes. PMID:25917213

α-Synuclein expression in the mouse cerebellum is restricted to VGluT1 excitatory terminals and is enriched in unipolar brush cells.

PubMed

Lee, Sun Kyong; Sillitoe, Roy V; Silva, Coralie; Martina, Marco; Sekerkova, Gabriella

2015-10-01

α-Synuclein has a crucial role in synaptic vesicle release and synaptic membrane recycling. Although its general expression pattern has been described in the cerebellum, the precise cerebellar structures where α-synuclein is localized are poorly understood. To address this question, we used α-synuclein immunohistochemistry in adult mice cerebellar sections. We found that α-synuclein labels glutamatergic but not glycinergic and GABAergic synaptic terminals in the molecular and granule cell layers. α-Synuclein was preferentially expressed in parallel and mossy fiber synaptic terminals that also express vesicular glutamate transporter 1 (VGluT1), while it was not detected in VGluT2-positive climbing fibers. α-Synuclein was particularly enriched in lobules IX and X, a region known to contain a high density of unipolar brush cells (UBCs). To elucidate whether the α-synuclein-positive mossy fibers belong to UBCs, we double-labeled cerebellar sections with antibodies to α-synuclein and UBC-type-specific markers (calretinin for type I and metabotropic glutamate receptor 1α (mGluR1α) for type II UBCs) and took advantage of organotypic cerebellar cultures (in which all mossy fibers are UBC axons) and moonwalker mice (in which almost all UBCs are ablated) and found that both type I and type II UBCs express α-synuclein. In moonwalker mutant cerebella, the α-synuclein/VGluT1 immunolabeling showed a dramatic decrease in the vestibulocerebellum that correlated with the absence of UBC. α-Synuclein appears to be an excellent marker for intrinsic mossy fibers of the VGluT1 subset in conjunction with UBCs of both subtypes.

Ionic Liquids and Cellulose: Dissolution, Chemical Modification and Preparation of New Cellulosic Materials

PubMed Central

Isik, Mehmet; Sardon, Haritz; Mecerreyes, David

2014-01-01

Due to its abundance and a wide range of beneficial physical and chemical properties, cellulose has become very popular in order to produce materials for various applications. This review summarizes the recent advances in the development of new cellulose materials and technologies using ionic liquids. Dissolution of cellulose in ionic liquids has been used to develop new processing technologies, cellulose functionalization methods and new cellulose materials including blends, composites, fibers and ion gels. PMID:25000264

Flame-retardant composite materials

NASA Technical Reports Server (NTRS)

Kourtides, Demetrius A.

1991-01-01

The properties of eight different graphite composite panels fabricated using four different resin matrices and two types of graphite reinforcement are described. The resin matrices included: VPSP/BMI, a blend of vinylpolystyryl pyridine and bismaleimide; BMI, a bismaleimide; and phenolic and PSP, a polystyryl pyridine. The graphite fiber used was AS-4 in the form of either tape or fabric. The properties of these composites were compared with epoxy composites. It was determined that VPSP/BMI with the graphite tape was the optimum design giving the lowest heat release rate.

BLENDING LOW ENRICHED URANIUM WITH DEPLETED URANIUM TO CREATE A SOURCE MATERIAL ORE THAT CAN BE PROCESSED FOR THE RECOVERY OF YELLOWCAKE AT A CONVENTIONAL URANIUM MILL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schutt, Stephen M.; Hochstein, Ron F.; Frydenlund, David C.

2003-02-27

Throughout the United States Department of Energy (DOE) complex, there are a number of streams of low enriched uranium (LEU) that contain various trace contaminants. These surplus nuclear materials require processing in order to meet commercial fuel cycle specifications. To date, they have not been designated as waste for disposal at the DOE's Nevada Test Site (NTS). Currently, with no commercial outlet available, the DOE is evaluating treatment and disposal as the ultimate disposition path for these materials. This paper will describe an innovative program that will provide a solution to DOE that will allow disposition of these materials atmore » a cost that will be competitive with treatment and disposal at the NTS, while at the same time recycling the material to recover a valuable energy resource (yellowcake) for reintroduction into the commercial nuclear fuel cycle. International Uranium (USA) Corporation (IUSA) and Nuclear Fuel Services, Inc. (NFS) have entered into a commercial relationship to pursue the development of this program. The program involves the design of a process and construction of a plant at NFS' site in Erwin, Tennessee, for the blending of contaminated LEU with depleted uranium (DU) to produce a uranium source material ore (USM Ore{trademark}). The USM Ore{trademark} will then be further processed at IUC's White Mesa Mill, located near Blanding, Utah, to produce conventional yellowcake, which can be delivered to conversion facilities, in the same manner as yellowcake that is produced from natural ores or other alternate feed materials. The primary source of feed for the business will be the significant sources of trace contaminated materials within the DOE complex. NFS has developed a dry blending process (DRYSM Process) to blend the surplus LEU material with DU at its Part 70 licensed facility, to produce USM Ore{trademark} with a U235 content within the range of U235 concentrations for source material. By reducing the U235 content to source material levels in this manner, the material will be suitable for processing at a conventional uranium mill under its existing Part 40 license to remove contaminants and enable the product to re-enter the commercial fuel cycle. The tailings from processing the USM Ore{trademark} at the mill will be permanently disposed of in the mill's tailings impoundment as 11e.(2) byproduct material. Blending LEU with DU to make a uranium source material ore that can be returned to the nuclear fuel cycle for processing to produce yellowcake, has never been accomplished before. This program will allow DOE to disposition its surplus LEU and DU in a cost effective manner, and at the same time provide for the recovery of valuable energy resources that would be lost through processing and disposal of the materials. This paper will discuss the nature of the surplus LEU and DU materials, the manner in which the LEU will be blended with DU to form a uranium source material ore, and the legal means by which this blending can be accomplished at a facility licensed under 10 CFR Part 70 to produce ore that can be processed at a conventional uranium mill licensed under 10 CFR Part 40.« less

Enrichment of probiotic ice cream with different dietary fibers: Structural characteristics and culture viability.

PubMed

Akalın, A S; Kesenkas, H; Dinkci, N; Unal, G; Ozer, E; Kınık, O

2018-01-01

This study evaluated the effect of 5 dietary fibers (apple, orange, oat, bamboo, and wheat) on the physicochemical, rheological, and textural characteristics; sensory properties; and culture viability of probiotic ice cream stored at -18°C for 180 d. The presence of orange and apple fibers increased the titratable acidity, decreased the lightness (color) value of the ice creams, and enhanced the red and yellow coloration. Compared with the control sample, the consistency indices and apparent viscosities of the experimental samples increased with the addition of all dietary fibers except oat fiber. The highest viscosity was obtained in the sample fortified with apple fiber, whereas the ice cream containing orange fiber showed the highest hardness after d 60 of storage. The addition of orange and apple fibers significantly increased melting resistance; however, panelists did not generally like these samples in terms of taste-flavor. All ice creams had viable counts of Lactobacillus acidophilus of ≥7 log cfu/g during storage except the samples with orange and bamboo fiber. Bifidobacterium lactis counts were also found to be >6 log cfu/g in those samples until d 150 of storage. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Perspective: Closing the Dietary Fiber Gap: An Ancient Solution for a 21st Century Problem12

PubMed Central

Thompson, Henry J; Brick, Mark A

2016-01-01

An important gap exists between the daily amounts of fiber recommended in the human diet (28–42 g/d) and that which is actually consumed (median intake, 12–14 g/d). In fact, <5% of Americans meet the recommended intake for dietary fiber, and the magnitude of the gap is large, approximately a 50–70% shortfall. Because considerable evidence indicates that dietary fiber affects normal physiologic function and the onset of chronic diseases and their progression, the fiber gap represents an opportune target at which dietary interventions can be directed. This perspective considers whether a scientific basis exists for the current lack of emphasis on pulse crops, that is, grain legumes (common bean, chickpea, lentils, and garden pea) as a concentrated, inexpensive, and widely available source of dietary fiber. Attention is directed to this topic because the fiber gap has existed for decades with little improvement despite nutrition labeling, consumer education about the value of whole-grain cereal crop-based products, and the introduction of many fiber-enriched foods. The time is long overdue to identify additional approaches that have the potential to close the dietary fiber gap. To this end, the potential role of pulse crops in remediating this gap is examined. PMID:27422499

Perspective: Closing the Dietary Fiber Gap: An Ancient Solution for a 21st Century Problem.

PubMed

Thompson, Henry J; Brick, Mark A

2016-07-01

An important gap exists between the daily amounts of fiber recommended in the human diet (28-42 g/d) and that which is actually consumed (median intake, 12-14 g/d). In fact, <5% of Americans meet the recommended intake for dietary fiber, and the magnitude of the gap is large, approximately a 50-70% shortfall. Because considerable evidence indicates that dietary fiber affects normal physiologic function and the onset of chronic diseases and their progression, the fiber gap represents an opportune target at which dietary interventions can be directed. This perspective considers whether a scientific basis exists for the current lack of emphasis on pulse crops, that is, grain legumes (common bean, chickpea, lentils, and garden pea) as a concentrated, inexpensive, and widely available source of dietary fiber. Attention is directed to this topic because the fiber gap has existed for decades with little improvement despite nutrition labeling, consumer education about the value of whole-grain cereal crop-based products, and the introduction of many fiber-enriched foods. The time is long overdue to identify additional approaches that have the potential to close the dietary fiber gap. To this end, the potential role of pulse crops in remediating this gap is examined. © 2016 American Society for Nutrition.

Effect of different fibers on dough properties and biscuit quality.

PubMed

Blanco Canalis, María S; Steffolani, María E; León, Alberto E; Ribotta, Pablo D

2017-03-01

This study forms part of a broader project aimed at understanding the role of fibers from different sources in high-fat, high-sugar biscuits and at selecting the best fibers for biscuit quality. The main purpose of this work was to understand the rheological and structural properties involved in fiber-enriched biscuit dough. High-amylose corn starch (RSII), chemically modified starch (RSIV), oat fiber (OF) and inulin (IN) were used at two different levels of incorporation (6 and 12 g) in dough formulation. The influence of fiber on the properties of biscuit dough was studied via dynamic rheological tests, confocal microscopy and spreading behavior. Biscuit quality was assessed by width/thickness factor, texture and surface characteristics, total dietary fiber and sensory evaluation. Main results indicated that IN incorporation increased the capacity of dough spreading during baking and thus improved biscuit quality. OF reduced dough spreading during baking and strongly increased its resistance to deformation. RSII and RSIV slightly affected the quality of the biscuits. Sensory evaluation revealed that the panel liked IN-incorporated biscuits as much as control biscuits. The increase in total dietary fiber modified dough behavior and biscuit properties, and the extent of these effects depended on the type of fiber incorporated. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

[Sensory evaluation of enteral nutritional supplements].

PubMed

Granell Vidal, Lina; Sánchez Juan, Carlos; Alfonso García, Antonio

2014-07-01

Enteral nutrition (EN) is indicated in patients who, although they may not eat enough food, maintain a sufficient function to receive, digest and absorb nutrients digestive system. Oral Nutritional Supplements (SON) are nutritionally complete or incomplete formulas (depending on whether or not provide all the nutrients needed to serve as the sole source of nutrients), which supplement inadequate oral diet. This study aims to evaluate the organoleptic characteristics of hyperproteic, normoproteic and fiber-enriched oral SON. SON test, carried out at the Department of Endocrinology and Nutrition Consortium Hospital General Universitario de Valencia from October 2012 to February 2013. 137 SON were evaluated in total, of which 47 were hyperproteic, 46 normoproteic and 44 enriched in fiber. Of the SON evaluated in the group of hyperproteic the following 3 SON obtained the best scores: Fresenius Prot Energy Drink® (21,27, vanilla flavor), Avant Standard Nut® (20.3 , strawberry flavor) and Resource® Protein (20.01, chocolate flavor) In the group of normoproteic SON the 3 best rated were: Ensure Plus® (22.3, banana flavor), Ensure Plus® (21.9, peach flavor) and Fresubin Energy Drink® (21, strawberry flavor) In the group of fiber-enriched the 3 SON most appreciated were: 2 Kcal Fresubin Fibre Drink® (23.78, vanilla flavor), Ensure Plus® TwoCal (22.9, banana flavor) and Fortimel Compact® (21.5, strawberry flavor) The study aims to guide clinicians on what SON may be more acceptable to the patient, so that the SON serve their purpose and restore or improve nutritional status, as the SON intervention is safe and cost - effective, since they improve both the functionality and quality of life. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Physicochemical and sensorial characteristics of noodle enriched with oyster mushroom (Pleorotus ostreatus) powder

NASA Astrophysics Data System (ADS)

Wahyono, A.; Novianti; Bakri, A.; Kasutjianingati

2018-01-01

Oyster Mushroom is a mushroom that can be used for food and medicine. It contains highly nutritious and functional substances such as statins and beta-glucan. A comprehensive evaluation of noodle-enriched with Oyster Mushroom powder has not been performed so far. In this study, we performed a comprehensive evaluation of noodle-enriched with Oyster Mushroom powder. The aim of this study was to assess the effects of enrichment of Oyster Mushroom Powder (OMP) on the quality of noodle. The quality of noodle was evaluated based on physical, chemical and sensorial characteristics. This study was done by substituting wheat flour with OMP at the level of 0 (control); 5; 7.5; 10; 12.5; and 15%. The results showed that OMP significantly affected (P<0.05) the chemical, physical and sensorial quality of enriched noodles. Increased OMP level concurrently increased ash, crude fiber content and water activity (Aw) of resulting noodles. The enrichment was significantly raised the redness and yellowness of noodles, but decreased whiteness index. In addition, the enrichment of OMP significantly affected the sensorial properties of enriched noodles including color, taste, aroma and texture. OMP enrichment can be done at the level of 5% without compromising color, aroma, and texture of noodle, but 12.5% for taste attribute. Thus, OMP enrichment is feasible to enhance the nutritional values of noodle.

Influence of Supplementation of Vegetable Oil Blends on Omega-3 Fatty Acid Production in Mortierella alpina CFR-GV15

PubMed Central

Vadivelan, Ganesan

2017-01-01

Objectives of this study were designed for improved production of mycelial omega-3 fatty acids with particular reference to EPA and DHA from the oleaginous fungus Mortierella alpina CFR-GV15 under submerged low temperatures fermentation supplemented with linseed oil and garden cress oil as an additional energy source. The fungus was grown at 20°C temperature for four days initially followed by 12°C temperature for next five days. The basal medium contained starch, yeast extract, and a blend of linseed oil (LSO) and garden cress oil (GCO) in the ratio 1 : 1. Results of the study revealed that, after nine days of total incubation period, the enhancement of biomass was up to 16.7 g/L dry weight with a total lipid content of 55.4% (v/w). Enrichment of omega-3 fatty acids indicated a significant increase in fatty acid bioconversion (ALA 32.2 ± 0.42%, EPA 7.9 ± 0.1%, and DHA 4.09 ± 0.2%) by 2.5-fold. The two-stage temperature cultivation alters the fatty acid profile due to activation of the desaturase enzyme in the cellular levels due to which arachidonic acid (AA) content reduced significantly. It can be concluded that Mortierella alpina CFR-GV15 is a fungal culture suitable for commercial production of PUFAs with enriched EPA and DHA. PMID:28466005

Nutritional composition, glycemic index, glycemic load, and organoleptical quality of glucomannan-enriched soy milk ice cream

NASA Astrophysics Data System (ADS)

Sa'adah, S.; Candra, O. M.; Nugrahani, G.; Pramono, A.; Afifah, D. N.

2018-01-01

Over the past decades, the number of childhood obesity cases has increased significantly, which led to an increase in the number of adults suffering from degenerative diseases such as diabetes mellitus (DM). Glucomannan-Enriched Soy Milk Ice Cream (GSMIC) may prevent obesity in children. The aim of the study was to test the level of carbohydrates, protein, fat, dietary fiber, glycemic index, glycemic load, and organoleptic quality of GSMIC. This experiment used a completely randomized design to test three formulations of glucomannan flour and soy milk (0.5%, 1.5%, and 2.5%). The products were tested for nutritional composition, and evaluated on glycemic index, glycemic load, and organoleptic quality. GSMIC 2.5% had higher levels of dietary fiber and high carbohydrate, protein, and fat content compared to ice cream (3.99%, 30.7%, 1.50%, 1.33%, respectively). The glycemic index of ice cream and 2.5% GSMIC were 75.83 (75%) and 51.48 (51%), respectively, while the glycemic load of ice cream and 2.5% GSMIC were 9.04 and 11.61, respectively. Based on the organoleptic analysis, formulation preferred by the panellists was 2.5% glucomannan flour. Glucomannan flour affected the level of carbohydrates, protein, fat, dietary fiber, glycemic index, glycemic load, and organoleptic quality in soy milk ice cream.

Influence of Reinforcement Anisotropy on the Stress Distribution in Tension and Shear of a Fusion Magnet Insulation System

NASA Astrophysics Data System (ADS)

Humer, K.; Raff, S.; Prokopec, R.; Weber, H. W.

2008-03-01

A glass fiber reinforced plastic laminate, which consists of half-overlapped wrapped Kapton/R-glass-fiber reinforcing tapes vacuum-pressure impregnated in a cyanate ester/epoxy blend, is proposed as the insulation system for the ITER Toroidal Field coils. In order to assess its mechanical performance under the actual operating conditions, cryogenic (77 K) tensile and interlaminar shear tests were done after irradiation to the ITER design fluence of 1×1022 m-2 (E>0.1 MeV). The data were then used for a Finite Element Method (FEM) stress analysis. We find that the mechanical strength and the fracture behavior as well as the stress distribution and the failure criteria are strongly influenced by the winding direction and the wrapping technique of the reinforcing tapes.

The Effect of Poly (Glycerol Sebacate) Incorporation within Hybrid Chitin-Lignin Sol-Gel Nanofibrous Scaffolds.

PubMed

Abudula, Tuerdimaimaiti; Gzara, Lassaad; Simonetti, Giovanna; Alshahrie, Ahmed; Salah, Numan; Morganti, Pierfrancesco; Chianese, Angelo; Fallahi, Afsoon; Tamayol, Ali; Bencherif, Sidi A; Memic, Adnan

2018-03-19

Chitin and lignin primarily accumulate as bio-waste resulting from byproducts of crustacean crusts and plant biomass. Recently, their use has been proposed for diverse and unique bioengineering applications, amongst others. However, their weak mechanical properties need to be improved in order to facilitate their industrial utilization. In this paper, we fabricated hybrid fibers composed of a chitin-lignin (CL)-based sol-gel mixture and elastomeric poly (glycerol sebacate) (PGS) using a standard electrospinning approach. Obtained results showed that PGS could be coherently blended with the sol-gel mixture to form a nanofibrous scaffold exhibiting remarkable mechanical performance and improved antibacterial and antifungal activity. The developed hybrid fibers showed promising potential in advanced biomedical applications such as wound care products. Ultimately, recycling these sustainable biopolymers and other bio-wastes alike could propel a "greener" economy.

Sustainability of Recycled ABS and PA6 by Banana Fiber Reinforcement: Thermal, Mechanical and Morphological Properties

NASA Astrophysics Data System (ADS)

Singh, Rupinder; Kumar, Ranvijay; Ranjan, Nishant

2018-01-01

In the present study efforts have been made to prepare functional prototypes with improved thermal, mechanical and morphological properties from polymeric waste for sustainability. The primary recycled acrylonitrile butadiene styrene (ABS) and polyamide 6 (PA6) has been selected as matrix material with bio-degradable and bio-compatible banana fibers (BF) as reinforcement. The blend (in form of feed stock filament wire) of ABS/PA6 and BF was prepared in house by conventional twin screw extrusion (TSE) process. Finally feed stock filament of ABS/PA6 reinforced with BF was put to run on open source fused deposition modelling based three dimensional printer (without any change in hardware/software of the system) for printing of functional prototypes with improved thermal/mechanical/morphological properties. The results are supported by photomicrographs, thermographs and mechanical testing.

Near-isogenic cotton germplasm lines that differ in fiber-bundle strength have temporal differences in fiber gene expression patterns as revealed by comparative high-throughput profiling.

PubMed

Hinchliffe, Doug J; Meredith, William R; Yeater, Kathleen M; Kim, Hee Jin; Woodward, Andrew W; Chen, Z Jeffrey; Triplett, Barbara A

2010-05-01

Gene expression profiles of developing cotton (Gossypium hirsutum L.) fibers from two near-isogenic lines (NILs) that differ in fiber-bundle strength, short-fiber content, and in fewer than two genetic loci were compared using an oligonucleotide microarray. Fiber gene expression was compared at five time points spanning fiber elongation and secondary cell wall (SCW) biosynthesis. Fiber samples were collected from field plots in a randomized, complete block design, with three spatially distinct biological replications for each NIL at each time point. Microarray hybridizations were performed in a loop experimental design that allowed comparisons of fiber gene expression profiles as a function of time between the two NILs. Overall, developmental expression patterns revealed by the microarray experiment agreed with previously reported cotton fiber gene expression patterns for specific genes. Additionally, genes expressed coordinately with the onset of SCW biosynthesis in cotton fiber correlated with gene expression patterns of other SCW-producing plant tissues. Functional classification and enrichment analysis of differentially expressed genes between the two NILs revealed that genes associated with SCW biosynthesis were significantly up-regulated in fibers of the high-fiber quality line at the transition stage of cotton fiber development. For independent corroboration of the microarray results, 15 genes were selected for quantitative reverse transcription PCR analysis of fiber gene expression. These analyses, conducted over multiple field years, confirmed the temporal difference in fiber gene expression between the two NILs. We hypothesize that the loci conferring temporal differences in fiber gene expression between the NILs are important regulatory sequences that offer the potential for more targeted manipulation of cotton fiber quality.

Novel value-added uses for sweet potato juice and flour in polyphenol- and protein-enriched functional food ingredients

USDA-ARS?s Scientific Manuscript database

Blackcurrant, blueberry, and muscadine grape juices were efficiently sorbed, concentrated, and stabilized into dry granular ingredient matrices which combined anti-inflammatory and antioxidant fruit polyphenols with sweet potato functional constituents (carotenoids, vitamins, polyphenols, fibers). T...

Rationale for Research on Including Sustainable Agriculture in the High School Agricultural Education Curriculum.

ERIC Educational Resources Information Center

Williams, David L.; Dollisso, Awoke D.

1998-01-01

Sustainable agriculture is a multidisciplinary approach to food and fiber problems. Its inclusion in the secondary curriculum would enrich and align it with social concerns. Research is needed in the scholarship functions of discovery, integrative approaches, and teaching. (SK)

Stromalized microreactor supports murine hematopoietic progenitor enrichment.

PubMed

Khong, Danika; Li, Matthew; Singleton, Amy; Chin, Ling-Yee; Parekkadan, Biju

2018-01-20

There is an emerging need to process, expand, and even genetically engineer hematopoietic stem and progenitor cells (HSPCs) prior to administration for blood reconstitution therapy. A closed-system and automated solution for ex vivo HSC processing can improve adoption and standardize processing techniques. Here, we report a recirculating flow bioreactor where HSCs are stabilized and enriched for short-term processing by indirect fibroblast feeder coculture. Mouse 3 T3 fibroblasts were seeded on the extraluminal membrane surface of a hollow fiber micro-bioreactor and were found to support HSPC cell number compared to unsupported BMCs. CFSE analysis indicates that 3 T3-support was essential for the enhanced intrinsic cell cycling of HSPCs. This enhanced support was specific to the HSPC population with little to no effect seen with the Lineage positive and Lineage negative cells. Together, these data suggest that stromal-seeded hollow fiber micro-reactors represent a platform to screening various conditions that support the expansion and bioprocessing of HSPCs ex vivo.

Development of functional spaghetti enriched in bioactive compounds using barley coarse fraction obtained by air classification.

PubMed

Verardo, Vito; Gómez-Caravaca, Ana Maria; Messia, Maria Cristina; Marconi, Emanuele; Caboni, Maria Fiorenza

2011-09-14

Barley byproducts obtained by air classification have been used to produce a different barley functional spaghetti, which were compared to different commercial whole semolina samples. Total, insoluble, and soluble fiber and β-glucan contents of the barley spaghetti were found to be greater than those of commercial samples. Furthermore, it was proved that barley spaghetti reached the FDA requirements, which could allow these pastas to deserve the health claims "good source of dietary fiber" and "may reduce the risk of heart disease". When the barley coarse fraction was used, a flavan-3-ols enrichment and an increase of antioxidant activity were reported, while commercial samples showed the absence of flavan-3-ols and a higher presence of phenolic acids and tannins. Whole semolina commercial spaghetti had a significantly higher content of phenolic acids than semolina spaghetti samples. Besides, it was observed that when vital gluten was added to the spaghetti formulation, phenolic compounds were blocked in the gluten network and were partially released during the cooking process.

Nutritional improvement of corn pasta-like product with broad bean (Vicia faba) and quinoa (Chenopodium quinoa).

PubMed

Giménez, M A; Drago, S R; Bassett, M N; Lobo, M O; Sammán, N C

2016-05-15

In this study, the nutritional quality of pasta-like product (spaghetti-type), made with corn (Zea mays) flour enriched with 30% broad bean (Vicia faba) flour and 20% of quinoa (Chenopodium quinoa) flour, was determined. Proximate chemical composition and iron, zinc and dietary fiber were determined. A biological assay was performed to assess the protein value using net protein utilization (NPU), true digestibility (TD) and protein digestibility-corrected amino acid score (PDCAAS). Iron and zinc availability were estimated by measuring dialyzable mineral fraction (%Da) resulting from in vitro gastrointestinal digestion. Nutritionally improved, gluten-free spaghetti (NIS) showed significantly increased NPU and decreased TD compared with a non-enriched control sample. One NIS-portion supplied 10-20% of recommended fiber daily intake. Addition of quinoa flour had a positive effect on the FeDa% as did broad bean flour on ZnDa%. EDTA increased Fe- and ZnDa% in all NIS-products, but it also impaired sensorial quality. Copyright © 2016. Published by Elsevier Ltd.

Fabrication, functionalization, and application of electrospun biopolymer nanofibers.

PubMed

Kriegel, Christina; Arecchi, Alessandra; Arrechi, Alessandra; Kit, Kevin; McClements, D J; Weiss, Jochen

2008-09-01

The use of novel nanostructured materials has attracted considerable interest in the food industry for their utilization as highly functional ingredients, high-performance packaging materials, processing aids, and food quality and safety sensors. Most previous application interest has focused on the development of nanoparticles. However, more recently, the ability to produce non-woven mats composed of nanofibers that can be used in food applications is beginning to be investigated. Electrospinning is a novel fabrication technique that can be used to produce fibers with diameters below 100 nm from (bio-) polymer solutions. These nanofibers have been shown to possess unique properties that distinguish them from non-woven fibers produced by other methods, e.g., melt-blowing. This is because first the process involved results in a high orientation of polymers within the fibers that leads to mechanically superior properties, e.g., increased tensile strengths. Second, during the spinning of the fibers from polymer solutions, the solvent is rapidly evaporated allowing the production of fibers composed of polymer blends that would typically phase separate if spun with other processes. Third, the small dimensions of the fibers lead to very high specific surface areas. Because of this the fiber properties may be greatly influenced by surface properties giving rise to fiber functionalities not found in fibers of larger sizes. For food applications, the fibers may find uses as ingredients if they are composed solely of edible polymers and GRAS ingredients, (e.g., fibers could contain functional ingredients such as nutraceuticals, antioxidants, antimicrobials, and flavors), as active packaging materials or as processing aids (e.g., catalytic reactors, membranes, filters (Lala et al., 2007), and sensors (Manesh et al., 2007; Ren et al., 2006; Sawicka et al., 2005). This review is therefore intended to introduce interested food and agricultural scientists to the concept of nano-fiber manufacturing with a particular emphasis on the use of biopolymers. We will review typical fabrication set-ups, discuss the influence of process conditions on nanofiber properties, and then review previous studies that describe the production of biopolymer-based nanofibers. Finally we briefly discuss emerging methods to further functionalize fibers and discuss potential applications in the area of food science and technology.

Inhomogeneities and segregation behavior in strontium—barium niobate fibers grown by laser-heated pedestal growth technique. Part II

NASA Astrophysics Data System (ADS)

Erdei, S.; Galambos, L.; Tanaka, I.; Hesselink, L.; Cross, L. E.; Feigelson, R. S.; Ainger, F. W.; Kojima, H.

1996-10-01

Inhomogeneities in Ce-doped and undoped fibers grown by laser-heated pedestal growth (LHPG) along the c- or a- axis were investigated by two-dimensional scanning electron microprobe analysis (SEPMA). SEPMA data indicated that these cores are primarily connected with the source rod compositions utilized and the convection characteristics of the LHPG technique. Ba enrichment and Sr decrease were primarily detected in the cores and qualitatively described in terms of the composition-control mechanism of LHPG, the complex-segregation and a modified Burton—Prim—Slichter (BPS) equation. Certain aspects of defect structure as a complex congruency related phenomenon are also discussed in the paper giving a more complete interpretation of the origin of cores in SBN fibers.

Group-velocity-locked vector soliton molecules in fiber lasers.

PubMed

Luo, Yiyang; Cheng, Jianwei; Liu, Bowen; Sun, Qizhen; Li, Lei; Fu, Songnian; Tang, Dingyuan; Zhao, Luming; Liu, Deming

2017-05-24

Physics phenomena of multi-soliton complexes have enriched the life of dissipative solitons in fiber lasers. By developing a birefringence-enhanced fiber laser, we report the first experimental observation of group-velocity-locked vector soliton (GVLVS) molecules. The birefringence-enhanced fiber laser facilitates the generation of GVLVSs, where the two orthogonally polarized components are coupled together to form a multi-soliton complex. Moreover, the interaction of repulsive and attractive forces between multiple pulses binds the particle-like GVLVSs together in time domain to further form compound multi-soliton complexes, namely GVLVS molecules. By adopting the polarization-resolved measurement, we show that the two orthogonally polarized components of the GVLVS molecules are both soliton molecules supported by the strongly modulated spectral fringes and the double-humped intensity profiles. Additionally, GVLVS molecules with various soliton separations are also observed by adjusting the pump power and the polarization controller.

Age hardening of 6061/alumina-silica fiber composite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khangaonkar, P.R.; Shamsul, J.B.; Azmi, R.

1994-12-31

Continuous alumina-silica fiber (Altex of Sumitomo) which yields high performance composites with some aluminium alloys was tried for squeeze cast 6061 based composites with volume fractions of 0.5 and 0.32, and the matrix microhardness and resistivity changes during age hardening were studied. The matrix in the composites hardened much more than the unreinforced alloy. Microhardness increases of up to 70 VPN above the solution treated condition at various aging temperatures were observed. The resistivity variation indicated an appreciable state of internal stress which continued to persist even when hardness fell by overaging. Energy dispersive X-ray analysis indicated that the regionsmore » close to the fibers had a higher silicon content than the matrix, and amorphous silica in the fiber may have a role in the formation of an enriched layer which may help the bonding and strength in the composite.« less

Flexural fatigue of short glass fiber reinforced a blend of polyphenylene ether ketone and polyphenylene sulfide

NASA Astrophysics Data System (ADS)

Zhou, Jiang; D'Amore, Alberto; Yang, Yuming; He, Tianbai; Li, Binyao; Nicolais, Luigi

1994-05-01

Flexural fatigue tests were conducted on injection molded glass fiber reinforced a blend of polyphenylene ether ketone and polyphenylene sulfide composite using four-point bending with different stress ratios and different frequencies. The fatigue behavior of this material was described. The constructed S-N curves shift their trends obviously at the maximum cyclic stress being about 80% of the ultimate flexural strength. Examinations of failure surfaces for various loading conditions show that the fatigue failure mechanisms appear to be matrix yielding at high stresses and crack growth at low stresses. Analyses of the fatigue data at various stress ratios reveal that the data at low stress superimpose to form a single curve which is nearly linear when they are plotted as stress range versus number of cycles to failure in bilogarithmic axes, while the data at high stresses also converge to yield a single curve when they are plotted as ( S max S range)1/2 against specimen lifetimes ( S max is the maximum stress and S range is the stress range). These results show that for the studied material the main factor influencing the lifetime is the stress range at low stresses and the parameter ( S max S range)1/2 at high stresses. Comparison of fatigue data in the frequency range of 0.89 7.0 Hz was made, no significant effect of frequency on the fatigue behavior is found.

Long-term Controlled Drug Release from bi-component Electrospun Fibers

NASA Astrophysics Data System (ADS)

Xu, Shanshan; Zhang, Zixin; Xia, Qinghua; Han, Charles

Multi-drug delivery systems with timed programmed release are hard to be produced due to the complex drug release kinetics which mainly refers to the diffusion of drug molecules from the fiber and the degradation of the carrier. This study focused on the whole life-time story of the long-term drug releasing fibrous systems. Electrospun membrane utilizing FDA approved polymers and broad-spectrum antibiotics showed specific drug release profiles which could be divided into three stages based on the profile slope. With throughout morphology observation, cumulative release amount and releasing duration, releasing kinetics and critical factors were fully discussed during three stages. Through changing the second component, approximately linear drug release profile and a drug release duration about 13 days was prepared, which is perfect for preventing post-operative infection. The addition of this semi-crystalline polymer in turn influenced the fiber swelling and created drug diffusion channels. In conclusion, through adjusting and optimization of the blending component, initial burst release, delayed release for certain duration, and especially the sustained release profile could all be controlled, as well as specific anti-bacterial behavior could be obtained.

Polypropylene/glass fiber hierarchical composites incorporating inorganic fullerene-like nanoparticles for advanced technological applications.

PubMed

Díez-Pascual, Ana M; Naffakh, Mohammed

2013-10-09

Novel isotactic polypropylene (iPP)/glass fiber (GF) laminates reinforced with inorganic fullerene-like tungsten disulfide (IF-WS2) nanoparticles as environmentally friendly fillers have been successfully fabricated by simple melt-blending and fiber impregnation in a hot-press without the addition of any compatibilizer. The influence of IF-WS2 concentration on the morphology, viscosity. and thermal and mechanical behavior of the hierarchical composites has been investigated. Results revealed an unprecedented 62 °C increase in the degradation temperature of iPP/GF upon addition of only 4.0 wt % IF-WS2. The coexistence of both micro- and nanoscale fillers resulted in synergistic effects on enhancing the stiffness, strength, crystallinity, thermal stability, glass transition (Tg) and heat distortion temperature (HDT) of the matrix. The approach used in this work is an efficient, versatile, scalable and economic strategy to improve the mechanical and thermal behavior of GF-reinforced thermoplastics with a view to extend their use in advanced technological applications. This new type of composite materials shows great potential to improve the efficiency and sustainability of many forms of transport.

[Synthesis and characterization of chromium doped Y3Al5O12 compound pigment].

PubMed

Yue, Shi-Juan; Su, Xiao; Jiang, Han-Jie; Liu, Shao-Xuan; Hong, You-Li; Zhang, Kai; Huang, Wan-Xias; Xiong, Zu-Jiang; Zhao, Ying; Liu, Cui-Ge; Wei, Yong-Ju; Meng, Tao; Xu, Yi-Zhuang; Wu, Jin-Guang

2012-09-01

The authors synthesized a new kind of green pigment via co-precipitation method by doping Y3Al5O12 with Cr+. The size of the pigment particles is around 200 nm as observed under scanning electron microscope. XRD results demonstrate that the pigment crystalline form of the pigment is yttrium alluminium garnet. UV-Vis spectra were used to investigate the coordination states and transition behavior of the doping ions. In addition, the colour feature was measured by CIE L* a* b* chroma value. The pigment was blended with polypropylene and then polypropylene fiber was produced using the polypropelene-pigment composite via molten spinning process. The distribution of the pigment particles in the polypropylene fibers was characterized by Xray computed tomography (CT) technique on the Beijing synchrotron radiation facility. The result states that the composite oxide pigment particles are homogeneously dispersed in the polypropylene fibers. The pigments are stable, non-toxic to the environment, and may be applied in non-aqueous dyeing to reduce waste water emitted by textile dyeing and printing industry.

Flexural properties untreated and treated kenaf fiber reinforced polypropylene composites

NASA Astrophysics Data System (ADS)

Husin, Muhammad Muslimin; Mustapa, Mohammad Sukri; Wahab, Md Saidin; Arifin, Ahmad Mubarak Tajul; Masirin, Mohd Idrus Mohd; Jais, Farhana Hazwanee

2017-05-01

Today natural fiber polymer composites are being extensively used as alternatives in producing furniture to fulfill society demand instead of saving cost and environmentally friendly. The objective of this search is to investigate the untreated fine and rough kenaf fiber (KF) as well as treated KF reinforced with polypropylene (PP) on the flexural strength. Flexural strengths of pure PP, 10%, and 20% of untreated fine and rough KF by weight to PP have been recorded. In addition, flexural strengths of treated KF soaked with 5% and 10% of Sodium Hydroxide (NaOH) have also been recorded. KF reinforced PP (PP/KF) untreated and treated composites were melt blended and then injection molded to observe their flexural strengths by measuring their threshold. Three point bending test was apply to determine the flexural stress of the composites. The result show treated fine KF produce better flexural performance at 20% PP/KF. Scanning Electron Microscopy (SEM) is used to observe the morphological surface PP/KF. Overall 5% NaOH with 20% PP/KF (Fine KF) show good interfacial bonding PP/KF and best result with flexural stress value 30.25MPa.

Hydrogen bonds of sodium alginate/Antarctic krill protein composite material.

PubMed

Yang, Lijun; Guo, Jing; Yu, Yue; An, Qingda; Wang, Liyan; Li, Shenglin; Huang, Xuelin; Mu, Siyang; Qi, Shanwei

2016-05-20

Sodium alginate/Antarctic krill protein composite material (SA/AKP) was successfully obtained by blending method. The hydrogen bonds of SA/AKP composite material were analyzed by Fourier transform infrared spectroscopy (FT-IR) and Nuclear magnetic resonance hydrogen spectrum (HNMR). Experiment manifested the existence of intermolecular and intramolecular hydrogen bonds in SA/AKP system; strength of intermolecular hydrogen bond enhanced with the increase of AKP in the composite material and the interaction strength of hydrogen bonding followed the order: OH…Ether O>OH…π>OH…N. The percentage of intermolecular hydrogen bond decreased with increase of pH. At the same time, the effect of hydrogen bonds on properties of the composite material was discussed. The increase of intermolecular hydrogen bonding led to the decrease of crystallinity, increase of apparent viscosity and surface tension, as well as obvious decrease of heat resistance of SA/AKP composite material. SA/AKP fiber SEM images and energy spectrum showed that crystallized salt was separated from the fiber, which possibly led to the fibrillation of the composite fibers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Direct transfer of metallic photonic structures onto end facets of optical fibers

NASA Astrophysics Data System (ADS)

Zhang, Xinping; Liu, Feifei; Lin, Yuanhai

2016-07-01

We present a flexible approach to transfer metallic photonic crystals (MPCs) onto end facets of optical fibers. The MPCs were initially fabricated on a glass substrate with a spacer layer of indium tin oxide (ITO), which was used as a buffer layer in the transferring process. The fiber ends were firstly welded on the top surface of the MPCs by a drop of polymer solution after the solvent evaporated. The ITO layer was then etched by hydrochloric acid (HCl), so that the MPCs got off the substrate and were transferred to the fiber ends. Alternatively, the MPCs may be also etched off the substrate first by immersing the sample in HCl. The ultra-thin MPC sheet consisting of gold nanolines interlaced with photoresist gratings was then transferred to cap the fiber ends. In the later approach, we can choose which side of the MPCs to be used as the contact with the fiber facet. Such methods enabled convenient nanostructuring on optical fiber tips and achieving miniaturized MPC devices with compact integration, extending significantly applications of MPCs. In particular, the fabrications presented in this manuscript enrich the lab-on-fiber engineering techniques and the resultant devices have potential applications in remote sensing and detection systems.

Graphene oxide decorated with silver nanoparticles as a coating on a stainless-steel fiber for solid-phase microextraction.

PubMed

Wang, Licheng; Hou, Xiudan; Li, Jubai; Liu, Shujuan; Guo, Yong

2015-07-01

A novel graphene oxide decorated with silver nanoparticles coating on a stainless-steel fiber for solid-phase microextraction was prepared. Scanning electron microscopy and X-ray photoelectron spectroscopy were used to characterize the coating surface and showed that silver nanoparticles were dispersed on the wrinkled graphene oxide surface. Coupled to gas chromatography with flame ionization detection, the extraction abilities of the fiber for polycyclic aromatic hydrocarbons were examined in the headspace solid-phase microextraction mode. The extraction parameters including adsorption time, adsorption temperature, salt concentration, desorption time and desorption temperature were investigated. Under the optimized condition, wide linearity with low limits of detection from 2 to 10 ng/L was obtained. The relative standard deviations for single-fiber repeatability and fiber-to-fiber reproducibility were less than 10.6 and 17.5%, respectively. The enrichment factors were from 1712.5 to 4503.7, showing the fiber has good extraction abilities. Moreover, the fiber exhibited a good stability and could be reused for more than 120 times. The established method was also applied for determination of polycyclic aromatic hydrocarbons in two real water samples and the recoveries of analytes ranged from 84.4-116.3% with relative standard deviations less than 16.2%. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Physical and Oxidative Stability of Flaxseed Oil-in-Water Emulsions Fabricated from Sunflower Lecithins: Impact of Blending Lecithins with Different Phospholipid Profiles.

PubMed

Liang, Li; Chen, Fang; Wang, Xingguo; Jin, Qingzhe; Decker, Eric Andrew; McClements, David Julian

2017-06-14

There is great interest in the formulation of plant-based foods enriched with nutrients that promote health, such as polyunsaturated fatty acids. This study evaluated the impact of sunflower phospholipid type on the formation and stability of flaxseed oil-in-water emulsions. Two sunflower lecithins (Sunlipon 50 and 90) with different phosphatidylcholine (PC) levels (59 and 90%, respectively) were used in varying ratios to form emulsions. Emulsion droplet size, charge, appearance, microstructure, and oxidation were measured during storage at 55 °C in the dark. The physical and chemical stability increased as the PC content of the lecithin blends decreased. The oxidative stability of emulsions formulated using Sunlipon 50 was better than emulsions formulated using synthetic surfactants (SDS or Tween 20). The results are interpreted in terms of the impact of emulsifier type on the colloidal interactions between oil droplets and on the molecular interactions between pro-oxidants and oil droplet surfaces.

Towards development of nanofibrous large strain flexible strain sensors with programmable shape memory properties

NASA Astrophysics Data System (ADS)

Khalili, N.; Asif, H.; Naguib, H. E.

2018-05-01

Electrospun polymeric fibers can be used as strain sensors due to their large surface to weight/volume ratio, high porosity and pore interconnectivity. Large strain flexible strain sensors are used in numerous applications including rehabilitation, health monitoring, and sports performance monitoring where large strain detection should be accommodated by the sensor. This has boosted the demand for a stretchable, flexible and highly sensitive sensor able to detect a wide range of mechanically induced deformations. Herein, a physically cross-linked polylactic acid (PLA) and thermoplastic polyurethane (TPU) blend is made into nanofiber networks via electrospinning. The PLA/TPU weight ratio is optimized to obtain a maximum attainable strain of 100% while maintaining its mechanical integrity. The TPU/PLA fibers also allowed for their thermally activated recovery due to shape memory properties of the substrate. This novel feature enhances the sensor’s performance as it is no longer limited by its plastic deformation. Using spray coating method, a homogeneous layer of single-walled carbon nanotube is deposited onto the as-spun fiber mat to induce electrical conductivity to the surface of the fibers. It is shown that stretching and bending the sensor result in a highly sensitive and linear response with a maximum gauge factor of 33.

Optimization strategies for electrospun silk fibroin tissue engineering scaffolds

PubMed Central

Meinel, Anne J.; Kubow, Kristopher E.; Klotzsch, Enrico; Garcia-Fuentes, Marcos; Smith, Michael L.; Vogel, Viola; Merkle, Hans P.; Meinel, Lorenz

2013-01-01

As a contribution to the functionality of scaffolds in tissue engineering, here we report on advanced scaffold design through introduction and evaluation of topographical, mechanical and chemical cues. For scaffolding, we used silk fibroin (SF), a well established biomaterial. Biomimetic alignment of fibers was achieved as a function of the rotational speed of the cylindrical target during electrospinning of a SF solution blended with polyethylene oxide. Seeding fibrous SF scaffolds with human mesenchymal stem cells (hMSC) demonstrated that fiber alignment could guide hMSC morphology and orientation demonstrating the impact of scaffold topography on the engineering of oriented tissues. Beyond currently established methodologies to measure bulk properties, we assessed the mechanical properties of the fibers by conducting extension at breakage experiments on the level of single fibers. Chemical modification of the scaffolds was tested using donor/acceptor fluorophore labeled fibronectin. Fluorescence resonance energy transfer imaging allowed to assess the conformation of fibronectin when adsorbed on the SF scaffolds, and demonstrated an intermediate extension level of its subunits. Biological assays based on hMSC showed enhanced cellular adhesion and spreading as a result of fibronectin adsorbed on the scaffolds. Our studies demonstrate the versatility of SF as a biomaterial to engineer modified fibrous scaffolds and underscore the use of biofunctionally relevant analytical assays to optimize fibrous biomaterial scaffolds. PMID:19233463

Flexure and impact properties of glass fiber reinforced nylon 6-polypropylene composites

NASA Astrophysics Data System (ADS)

Kusaseh, N. M.; Nuruzzaman, D. M.; Ismail, N. M.; Hamedon, Z.; Azhari, A.; Iqbal, A. K. M. A.

2018-03-01

In recent years, polymer composites are rapidly developing and replacing the metals or alloys in numerous engineering applications. These polymer composites are the topic of interests in industrial applications such as automotive and aerospace industries. In the present research study, glass fiber (GF) reinforced nylon 6 (PA6)-polypropylene (PP) composite specimens were prepared successfully using injection molding process. Test specimens of five different compositions such as, 70%PA6+30%PP, 65%PA6+30%PP+5%GF, 60%PA6+30%PP+10%GF, 55%PA6+30%PP+15%GF and 50%PA6+30%PP+20%GF were prepared. In the experiments, flexure and impact tests were carried out. The obtained results revealed that flexure and impact properties of the polymer composites were significantly influenced by the glass fiber content. Results showed that flexural strength is low for pure polymer blend and flexural strength of GF reinforced composite increases gradually with the increase in glass fiber content. Test results also revealed that the impact strength of 70%PA6+30%PP is the highest and 55%PA6+30%PP+15%GF composite shows moderate impact strength. On the other hand, 50%PA6+30%PP+20%GF composite shows low toughness or reduced impact strength.

Seamless, axially aligned, fiber tubes, meshes, microbundles and gradient biomaterial constructs

PubMed Central

Elia, Roberto; Firpo, Matthew A.; Kaplan, David L.; Peattie, Robert A.

2012-01-01

A new electrospinning apparatus was developed to generate nanofibrous materials with improved organizational control. The system functions by oscillating the deposition signal (ODS) of multiple collectors, allowing significantly improved nanofiber control by manipulating the electric field which drives the electrospinning process. Other electrospinning techniques designed to impart deposited fiber organizational control, such as rotating mandrels or parallel collector systems, do not generate seamless constructs with high quality alignment in sizes large enough for medical devices. In contrast, the ODS collection system produces deposited fiber networks with highly pure alignment in a variety of forms and sizes, including flat (8 × 8 cm2), tubular (1.3 cm diameter), or rope-like microbundle (45 μm diameter) samples. Additionally, the mechanism of our technique allows for scale-up beyond these dimensions. The ODS collection system produced 81.6 % of fibers aligned within 5° of the axial direction, nearly a four-fold improvement over the rotating mandrel technique. The meshes produced from the 9 % (w/v) fibroin/PEO blend demonstrated significant mechanical anisotropy due to the fiber alignment. In 37 °C PBS, aligned samples produced an ultimate tensile strength of 16.47 ± 1.18 MPa, a Young's modulus of 37.33 MPa, and a yield strength of 7.79 ± 1.13 MPa. The material was 300 % stiffer when extended in the direction of fiber alignment and required 20 times the amount of force to be deformed, compared to aligned meshes extended perpendicular to the fiber direction. The ODS technique could be applied to any electrospinnable polymer to overcome the more limited uniformity and induced mechanical strain of rotating mandrel techniques, and greatly surpasses the limited length of standard parallel collector techniques. PMID:22890517

Activation of Organic Photovoltaic Light Detectors Using Bend Leakage from Optical Fibers.

PubMed

Griffith, Matthew J; Willis, Matthew S; Kumar, Pankaj; Holdsworth, John L; Bezuidenhout, Henco; Zhou, Xiaojing; Belcher, Warwick; Dastoor, Paul C

2016-03-01

This work investigates the detection and subsequent utilization of leaked light from bends in a silica optical fiber using organic photovoltaic detectors. The optic power lost by single mode and multimode silica optical fibers was calibrated for bend radii between 1 and 7 mm for 532 and 633 nm light, exhibiting excellent agreement with previous theoretical solutions. The spatial location of maximum power leakage on the exterior of the fiber was found to exist in the same plane as the fiber, with a 10° offset from the normal. Two different organic photovoltaic detectors fabricated using a poly(3-hexylthiophene):indene-C60-bisadduct donor-acceptor blend cast from chloroform and chlorobenzene were fabricated to detect the leaked light. The two detectors exhibited different photovoltaic performances, predominantly due to different active layer thicknesses. Both devices showed sensitivity to leakage light, exhibiting voltages between 200 and 300 mV in response to leaked light from the fiber. The temporal responses of the devices were observed to differ, with a rise time from 10% to 90% of maximum voltage of 1430 μs for the chlorobenzene device, and a corresponding rise time of 490 μs for the higher performing chloroform device. The two OPVs were used to simultaneously detect leaked light from induced bends in the optical fiber, with the differing temporal profiles employed to create a unique time-correlated detection signal with enhanced security. The delay between detection of each OPV voltage could be systematically varied, allowing for either a programmable and secure single detection signal or triggering of multiple events with variable time resolution. The results reported in this study present exciting avenues toward the deployment of this simple and noninvasive optical detection system in a range of different applications.

Conformational study of 13C-enriched fibroin in the solid state, using the cross polarization nuclear magnetic resonance method.

PubMed

Fujiwara, T; Kobayashi, Y; Kyogoku, Y; Kataoka, K

1986-01-05

Silk fibroin with the alanyl carboxyl carbon enriched with 13C was obtained by giving a diet containing 13C-enriched alanine to the larvae of Bombyx mori and Antheraea pernyi at the fifth instar. Sericin-free fibroin fibers were prepared from cocoons, and gut was made from the liquid silk in the gland. The final 13C content was about 13%. Cross polarization/magic angle sample spinning spectra at 25 MHz and 75 MHz were measured for each sample at different orientations. Spectra were simulated using the principal values and orientations of the shielding tensor in the alanine crystal. The results indicate that the beta-structure of the fibroin may be a little more flattened than the typical pleated sheet beta-structure.

The Effect of Poly (Glycerol Sebacate) Incorporation within Hybrid Chitin–Lignin Sol–Gel Nanofibrous Scaffolds

PubMed Central

Abudula, Tuerdimaimaiti; Gzara, Lassaad; Simonetti, Giovanna; Alshahrie, Ahmed; Salah, Numan; Morganti, Pierfrancesco; Chianese, Angelo; Fallahi, Afsoon; Tamayol, Ali; Memic, Adnan

2018-01-01

Chitin and lignin primarily accumulate as bio-waste resulting from byproducts of crustacean crusts and plant biomass. Recently, their use has been proposed for diverse and unique bioengineering applications, amongst others. However, their weak mechanical properties need to be improved in order to facilitate their industrial utilization. In this paper, we fabricated hybrid fibers composed of a chitin–lignin (CL)-based sol–gel mixture and elastomeric poly (glycerol sebacate) (PGS) using a standard electrospinning approach. Obtained results showed that PGS could be coherently blended with the sol–gel mixture to form a nanofibrous scaffold exhibiting remarkable mechanical performance and improved antibacterial and antifungal activity. The developed hybrid fibers showed promising potential in advanced biomedical applications such as wound care products. Ultimately, recycling these sustainable biopolymers and other bio-wastes alike could propel a “greener” economy. PMID:29562729

Rice bran oil, not fiber, lowers cholesterol in humans.

PubMed

Most, Marlene M; Tulley, Richard; Morales, Silvia; Lefevre, Michael

2005-01-01

The cholesterol-lowering abilities of rice bran's fiber and oil apart from its fatty acid composition remain unclear. The objective of the study was to assess the effects of defatted rice bran and rice bran oil in an average American diet on blood lipids in moderately hypercholesterolemic persons. Study 1 used a parallel-arm design. Twenty-six healthy volunteers consumed a diet with 13-22 g dietary fiber/d for 3 wk, and then 13 of the volunteers were switched to a diet with defatted rice bran to double the fiber intake for 5 wk. Study 2 was a randomized, crossover, 10-wk feeding study performed in 14 volunteers who consumed a diet with rice bran oil (1/3 of the total dietary fat) substituted for an oil blend that had a fatty acid composition similar to that of the rice bran oil. Serum lipids and factor VII were measured in both studies. Defatted rice bran did not lower lipid concentrations. In study 2, total cholesterol was significantly lower with consumption of the diet containing rice bran oil than with consumption of the control diet. Moreover, with consumption of the rice bran oil diet, LDL cholesterol decreased by 7% (P < 0.0004), whereas HDL cholesterol was unchanged. Rice bran oil, not fiber, lowers cholesterol in healthy, moderately hypercholesterolemic adults. There were no substantial differences in the fatty acid composition of the diets; therefore, the reduction of cholesterol was due to other components present in the rice bran oil, such as unsaponifiable compounds.

Progress report 3 of cooperative program for design, fabrication, and testing of high modulus composite helicopter shafting

NASA Technical Reports Server (NTRS)

Wright, C. C.; Baker, D. J.

1980-01-01

This report describes the third phase of work, the objective of which was to overcome the excessive brittleness of the previously developed UH-1 helicopter tail rotor drive shaft design which demonstrated a shaft train weight savings of 53.1% over the current 2024-T3 aluminum shaft train. A materials impact program demonstrated exceptionally noteworthy performance of two woven constructions containing E-glass and PRD 49-III (designation later changed to KEVLAR 49) fibers in an epoxy resin matrix. Thermoplastic matrices and PRD 49-III fiber provided impact resistance at low weight which was superior to composites having the same fiber in a thermoset resin matrix. A design, fabrication, and test program showed that shaft impact resistance could be improved over the previously developed graphite composite design at a cost in shaft train rate savings. The shaft train weight savings of the most impact tolerant construction was 4.0% over the current aluminum shaft train. Alternating plies of graphite and glass appear to provide substantially greater tube impact durability than that provided by hybridization of the two fibers into one tape wound to a ply design equivalent in strength and stiffness to that of the alternating ply design. Recommendations were made to continue research work to exploit the potential for more impact-durable structures through the use of KEVLAR 49 fiber, woven structures, thermoplastic matrices and THORNEL 50-S/KEVLAR 49 blends with thermoset matrices.

Fiber/collagen composites for ligament tissue engineering: influence of elastic moduli of sparse aligned fibers on mesenchymal stem cells.

PubMed

Thayer, Patrick S; Verbridge, Scott S; Dahlgren, Linda A; Kakar, Sanjeev; Guelcher, Scott A; Goldstein, Aaron S

2016-08-01

Electrospun microfibers are attractive for the engineering of oriented tissues because they present instructive topographic and mechanical cues to cells. However, high-density microfiber networks are too cell-impermeable for most tissue applications. Alternatively, the distribution of sparse microfibers within a three-dimensional hydrogel could present instructive cues to guide cell organization while not inhibiting cell behavior. In this study, thin (∼5 fibers thick) layers of aligned microfibers (0.7 μm) were embedded within collagen hydrogels containing mesenchymal stem cells (MSCs), cultured for up to 14 days, and assayed for expression of ligament markers and imaged for cell organization. These microfibers were generated through the electrospinning of polycaprolactone (PCL), poly(ester-urethane) (PEUR), or a 75/25 PEUR/PCL blend to produce microfiber networks with elastic moduli of 31, 15, and 5.6 MPa, respectively. MSCs in composites containing 5.6 MPa fibers exhibited increased expression of the ligament marker scleraxis and the contractile phenotype marker α-smooth muscle actin versus the stiffer fiber composites. Additionally, cells within the 5.6 MPa microfiber composites were more oriented compared to cells within the 15 and 31 MPa microfiber composites. Together, these data indicate that the mechanical properties of microfiber/collagen composites can be tuned for the engineering of ligament and other target tissues. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1894-1901, 2016. © 2016 Wiley Periodicals, Inc.

Stabilization, Rolling, and Addition of Other Extracellular Matrix Proteins to Collagen Hydrogels Improve Regeneration in Chitosan Guides for Long Peripheral Nerve Gaps in Rats.

PubMed

Gonzalez-Perez, Francisco; Cobianchi, Stefano; Heimann, Claudia; Phillips, James B; Udina, Esther; Navarro, Xavier

2017-03-01

Autograft is still the gold standard technique for the repair of long peripheral nerve injuries. The addition of biologically active scaffolds into the lumen of conduits to mimic the endoneurium of peripheral nerves may increase the final outcome of artificial nerve devices. Furthermore, the control of the orientation of the collagen fibers may provide some longitudinal guidance architecture providing a higher level of mesoscale tissue structure. To evaluate the regenerative capabilities of chitosan conduits enriched with extracellular matrix-based scaffolds to bridge a critical gap of 15 mm in the rat sciatic nerve. The right sciatic nerve of female Wistar Hannover rats was repaired with chitosan tubes functionalized with extracellular matrix-based scaffolds fully hydrated or stabilized and rolled to bridge a 15 mm nerve gap. Recovery was evaluated by means of electrophysiology and algesimetry tests and histological analysis 4 months after injury. Stabilized constructs enhanced the success of regeneration compared with fully hydrated scaffolds. Moreover, fibronectin-enriched scaffolds increased muscle reinnervation and number of myelinated fibers compared with laminin-enriched constructs. A mixed combination of collagen and fibronectin may be a promising internal filler for neural conduits for the repair of peripheral nerve injuries, and their stabilization may increase the quality of regeneration over long gaps. Copyright © 2017 by the Congress of Neurological Surgeons

The Myosin IXb Motor Activity Targets the Myosin IXb RhoGAP Domain as Cargo to Sites of Actin Polymerization

PubMed Central

van den Boom, Frank; Düssmann, Heiko; Uhlenbrock, Katharina; Abouhamed, Marouan

2007-01-01

Myosin IXb (Myo9b) is a single-headed processive myosin that exhibits Rho GTPase-activating protein (RhoGAP) activity in its tail region. Using live cell imaging, we determined that Myo9b is recruited to extending lamellipodia, ruffles, and filopodia, the regions of active actin polymerization. A functional motor domain was both necessary and sufficient for targeting Myo9b to these regions. The head domains of class IX myosins comprise a large insertion in loop2. Deletion of the large Myo9b head loop 2 insertion abrogated the enrichment in extending lamellipodia and ruffles, but enhanced significantly the enrichment at the tips of filopodia and retraction fibers. The enrichment in the tips of filopodia and retraction fibers depended on four lysine residues C-terminal to the loop 2 insertion and the tail region. Fluorescence recovery after photobleaching and photoactivation experiments in lamellipodia revealed that the dynamics of Myo9b was comparable to that of actin. The exchange rates depended on the Myo9b motor region and motor activity, and they were also dependent on the turnover of F-actin. These results demonstrate that Myo9b functions as a motorized RhoGAP molecule in regions of actin polymerization and identify Myo9b head sequences important for in vivo motor properties. PMID:17314409

[Study of tolerance and aceptability of a hyperproteic enteral formula enriched in fiber].

PubMed

De Luis, Daniel Antonio; Izaola, Olatz; Castro, A; Martin, M; Torres, B; Lopez Gomez, Jj; Gomez Hoyos, E; Blanco Naveira, Mercedes

2014-10-18

To evaluate the gastrointestinal tolerance and acceptance of the new formulation of Isosource Protein ® Fibre® with a new blend of fibers IS50®. Opened, non-comparative, nonrandomized, descriptive study in patients requiring full enteral tube feeding for at least 7 days. Gastrointestinal tolerance was assessed by daily record of subjective gastrointestinal symptoms by the patient, and objectives behind the abdominal exploration by the researcher for up to 15 days. 18 patients were included with a mean age of 67.32 ± 13.8 years, of whom 66.7% were male. The average actual weight of the sample was 68.7 ± 9.8 kg (range: 51-90 kg) and BMI 24.0 ± 4.0 kg/m2 (range: 16.0 to 32.00 kg/m2). The average volume prescribed Isosource Protein® Fiber® was 1580 ± 282.7 ml / day (range: 1200 to 2000 ml/day). 72.22% of the patients received 1500 ml/day, received 16.67% 1750 ml / day, 5.56% received 2000 ml/day and 5.56% received 2500 ml/day. The analysis of the gastrointestinal tolerance of patients revealed that in the first study visit, reported no significant gastrointestinal problems, only one patient indicated the presence of mild constipation. By contrast, in the last study visit, it was observed that two patients reported constipation (mild to moderate) and two patients reported diarrhea (mild and severe). As for the evaluation of gastrointestinal tolerance by the investigator and depositional habit, the results show that in 100% cases tolerance was normal. Regarding the depositional habit, it was observed than the 66.7% of patients had no bowel movements at baseline, compared to 33.4% at the last visit of the patient (p = 0.035). In this sense, a significant increase (p = 0.035) in the mean number of daily bowel movements at the final visit (0.89 ± 0.90, range: 0-3) was observed, compared to the initial visit (0.44 ± 0.78, range: 0-3). Isosource Protein® Fibre® has proved a formula for enteral nutrition well tolerated, with a very low frequency of gastrointestinal symptoms and an improvement in the number of stools, which encourages compliance with the standard prescribed by the health professional and suggest a positive effect on the regulation of intestinal transit. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Strong Keratin-like Nanofibers Made of Globular Protein

NASA Astrophysics Data System (ADS)

Dror, Yael; Makarov, Vadim; Admon, Arie; Zussman, Eyal

2008-03-01

Protein fibers as elementary structural and functional elements in nature inspire the engineering of protein-based products for versatile bio-medical applications. We have recently used the electrospinning process to fabricate strong sub-micron fibers made solely of serum albumin (SA). This raises the challenges of turning a globular non-viscous protein solution into a polymer--like spinnable solution and producing keratin-like fibers enriched in inter S-S bridges. A stable spinning process was achieved by using SA solution in a rich trifluoroethanol-water mixture with β-mercaptoethanol. The breakage of the intra disulfide bridges, as identified by mass spectrometry, together with the denaturing alcohol, enabled a pronounced expansion of the protein. This in turn, affects the rheological properties of the solution. X-ray diffraction pattern of the fibers revealed equatorial orientation, indicating the alignment of structures along the fiber axis. The mechanical properties reached remarkable average values (Young's modulus of 1.6GPa, and max stress of 36MPa) as compared to other fibrous protein nanofibers. These significant results are attributed to both the alignment and inter disulfide bonds (cross linking) that were formed by spontaneous post-spinning oxidation.

Fiber-Mediated Nourishment of Gut Microbiota Protects against Diet-Induced Obesity by Restoring IL-22-Mediated Colonic Health.

PubMed

Zou, Jun; Chassaing, Benoit; Singh, Vishal; Pellizzon, Michael; Ricci, Matthew; Fythe, Michael D; Kumar, Matam Vijay; Gewirtz, Andrew T

2018-01-10

Dietary supplementation with fermentable fiber suppresses adiposity and the associated parameters of metabolic syndrome. Microbiota-generated fiber-derived short-chain fatty acids (SCFAs) and free fatty acid receptors including GPR43 are thought to mediate these effects. We find that while fermentable (inulin), but not insoluble (cellulose), fiber markedly protected mice against high-fat diet (HFD)-induced metabolic syndrome, the effect was not significantly impaired by either inhibiting SCFA production or genetic ablation of GPR43. Rather, HFD decimates gut microbiota, resulting in loss of enterocyte proliferation, leading to microbiota encroachment, low-grade inflammation (LGI), and metabolic syndrome. Enriching HFD with inulin restored microbiota loads, interleukin-22 (IL-22) production, enterocyte proliferation, and antimicrobial gene expression in a microbiota-dependent manner, as assessed by antibiotic and germ-free approaches. Inulin-induced IL-22 expression, which required innate lymphoid cells, prevented microbiota encroachment and protected against LGI and metabolic syndrome. Thus, fermentable fiber protects against metabolic syndrome by nourishing microbiota to restore IL-22-mediated enterocyte function. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparative Metagenomics of Cellulose- and Poplar Hydrolysate-Degrading Microcosms from Gut Microflora of the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus) after Long-Term Enrichment

PubMed Central

Wong, Mabel T.; Wang, Weijun; Couturier, Marie; Razeq, Fakhria M.; Lombard, Vincent; Lapebie, Pascal; Edwards, Elizabeth A.; Terrapon, Nicolas; Henrissat, Bernard; Master, Emma R.

2017-01-01

To identify carbohydrate-active enzymes (CAZymes) that might be particularly relevant for wood fiber processing, we performed a comparative metagenomic analysis of digestive systems from Canadian beaver (Castor canadensis) and North American moose (Alces americanus) following 3 years of enrichment on either microcrystalline cellulose or poplar hydrolysate. In total, 9,386 genes encoding CAZymes and carbohydrate-binding modules (CBMs) were identified, with up to half predicted to originate from Firmicutes, Bacteroidetes, Chloroflexi, and Proteobacteria phyla, and up to 17% from unknown phyla. Both PCA and hierarchical cluster analysis distinguished the annotated glycoside hydrolase (GH) distributions identified herein, from those previously reported for grass-feeding mammals and herbivorous foragers. The CAZyme profile of moose rumen enrichments also differed from a recently reported moose rumen metagenome, most notably by the absence of GH13-appended dockerins. Consistent with substrate-driven convergence, CAZyme profiles from both poplar hydrolysate-fed cultures differed from cellulose-fed cultures, most notably by increased numbers of unique sequences belonging to families GH3, GH5, GH43, GH53, and CE1. Moreover, pairwise comparisons of moose rumen enrichments further revealed higher counts of GH127 and CE15 families in cultures fed with poplar hydrolysate. To expand our scope to lesser known carbohydrate-active proteins, we identified and compared multi-domain proteins comprising both a CBM and domain of unknown function (DUF) as well as proteins with unknown function within the 416 predicted polysaccharide utilization loci (PULs). Interestingly, DUF362, identified in iron–sulfur proteins, was consistently appended to CBM9; on the other hand, proteins with unknown function from PULs shared little identity unless from identical PULs. Overall, this study sheds new light on the lignocellulose degrading capabilities of microbes originating from digestive systems of mammals known for fiber-rich diets, and highlights the value of enrichment to select new CAZymes from metagenome sequences for future biochemical characterization. PMID:29326667

Groundwater ecosystem resilience to organic contaminations: microbial and geochemical dynamics throughout the 5-year life cycle of a surrogate ethanol blend fuel plume.

PubMed

Ma, Jie; Nossa, Carlos W; Alvarez, Pedro J J

2015-09-01

The capacity of groundwater ecosystem to recover from contamination by organic chemicals is a vital concern for environmental scientists. A pilot-scale aquifer system was used to investigate the long-term dynamics of contaminants, groundwater geochemistry, and microbial community structure (by 16S rRNA gene pyrosequencing and quantitative real-time PCR) throughout the 5-year life cycle of a surrogate ethanol blend fuel plume (10% ethanol + 50 mg/L benzene + 50 mg/L toluene). Two-year continuous ethanol-blended release significantly changed the groundwater geochemistry (resulted in anaerobic, low pH, and organotrophic conditions) and increased bacterial and archaeal populations by 82- and 314-fold respectively. Various anaerobic heterotrophs (fermenters, acetogens, methanogens, and hydrocarbon degraders) were enriched. Two years after the release was shut off, all contaminants and their degradation byproducts disappeared and groundwater geochemistry completely restored to the pre-release states (aerobic, neutral pH, and oligotrophic). Bacterial and archaeal populations declined by 18- and 45-fold respectively (relative to the time of shut off). Microbial community structure reverted towards the pre-release states and alpha diversity indices rebounded, suggesting the resilience of microbial community to ethanol blend releases. We also found shifts from O2-sensitive methanogens (e.g., Methanobacterium) to methanogens that are not so sensitive to O2 (e.g., Methanosarcina and Methanocella), which is likely to contribute to the persistence of methanogens and methane generation following the source removal. Overall, the rapid disappearance of contaminants and their metabolites, rebound of geochemical footprints, and resilience of microbial community unequivocally document the natural capacity of groundwater ecosystem to attenuate and recover from a large volume of catastrophic spill of ethanol-based biofuel. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of adherence by elderly nursing home patients to regular consumption of apple compote enriched with protein and soluble fiber.

PubMed

Allaert, F A; Guérin-Deremaux, L; Mauray-Soulier, A; Saniez-Degrave, M H

2016-04-01

An increase in daily doses of protein and fiber for the elderly is relevant in preventing sarcopenia and preserving intestinal balance. However, such intake of supplements is often compromised by the lack of adherence among the elderly. The main objective was to evaluate the perception of the hedonic qualities of compote enriched with NUTRALYS(®) pea protein, NUTRALYS(®)W hydrolyzed wheat gluten and NUTRIOSE(®) soluble fiber and the changes in that perception due to repeated consumption. The secondary objectives were to evaluate the evolution in the quantity of compote eaten, satisfaction with consumption and any changes in fatigue, digestive comfort and digestive tolerance when eating compote every other day for 3 weeks. An observational study was conducted in nursing homes on volunteers aged 70-90 years. The compote was proposed as a lunchtime dessert every two days for a period of three consecutive weeks. All criteria were evaluated at days D0 and/or D1, D7, D15 and D21, except for the amount of compote eaten, evaluated after each meal at which it was served. When first tasted, the compote was judged 'rather pleasant' to 'very pleasant' by 91.6 % and this rating held up at 79.2 % (p = 0.1797) after 1 week, 83.3 % (p = 0.3173) after 2 weeks and 79.2 % (p = 0.2568) after 3 weeks. Average consumption of compote was stable and varied between a maximum of 79.5 % of the total quantity at inclusion to a minimum of 61.5 % recorded on D17. The other parameters did not change significantly. Pea protein, hydrolyzed wheat gluten and soluble fiber seem to provide an appropriate form of protein and fiber supplementation in the diets of elderly people in nursing homes.

Cellulase production by Penicillium funiculosum and its application in the hydrolysis of sugar cane bagasse for second generation ethanol production by fed batch operation.

PubMed

Maeda, Roberto Nobuyuki; Barcelos, Carolina Araújo; Santa Anna, Lídia Maria Melo; Pereira, Nei

2013-01-10

This study aimed to produce a cellulase blend and to evaluate its application in a simultaneous saccharification and fermentation (SSF) process for second generation ethanol production from sugar cane bagasse. The sugar cane bagasse was subjected to pretreatments (diluted acid and alkaline), as for disorganizing the ligocellulosic complex, and making the cellulose component more amenable to enzymatic hydrolysis. The residual solid fraction was named sugar cane bagasse partially delignified cellulignin (PDC), and was used for enzyme production and ethanol fermentation. The enzyme production was performed in a bioreactor with two inoculum concentrations (5 and 10% v/v). The fermentation inoculated with higher inoculum size reduced the time for maximum enzyme production (from 72 to 48). The enzyme extract was concentrated using tangential ultrafiltration in hollow fiber membranes, and the produced cellulase blend was evaluated for its stability at 37 °C, operation temperature of the simultaneous SSF process, and at 50 °C, optimum temperature of cellulase blend activity. The cellulolytic preparation was stable for at least 300 h at both 37 °C and 50 °C. The ethanol production was carried out by PDC fed-batch SSF process, using the onsite cellulase blend. The feeding strategy circumvented the classic problems of diffusion limitations by diminishing the presence of a high solid:liquid ratio at any time, resulting in high ethanol concentration at the end of the process (100 g/L), which corresponded to a fermentation efficiency of 78% of the maximum obtainable theoretically. The experimental results led to the ratio of 380 L of ethanol per ton of sugar cane bagasse PDC. Copyright © 2012 Elsevier B.V. All rights reserved.

Preparation of Pure and Stable Chitosan Nanofibers by Electrospinning in the Presence of Poly(ethylene oxide)

PubMed Central

Mengistu Lemma, Solomon; Bossard, Frédéric; Rinaudo, Marguerite

2016-01-01

Electrospinning was employed to obtain chitosan nanofibers from blends of chitosans (CS) and poly(ethylene oxide) (PEO). Blends of chitosan (MW (weight-average molecular weight) = 102 kg/mol) and PEO (M (molecular weight) = 1000 kg/mol) were selected to optimize the electrospinning process parameters. The PEO powder was solubilized into chitosan solution at different weight ratios in 0.5 M acetic acid. The physicochemical changes of the nanofibers were determined by scanning electron microscopy (SEM), swelling capacity, and nuclear magnetic resonance (NMR) spectroscopy. For stabilization, the produced nanofibers were neutralized with K2CO3 in water or 70% ethanol/30% water as solvent. Subsequently, repeated washings with pure water were performed to extract PEO, potassium acetate and carbonate salts formed in the course of chitosan nanofiber purification. The increase of PEO content in the blend from 20 to 40 w% exhibited bead-free fibers with average diameters 85 ± 19 and 147 ± 28 nm, respectively. Their NMR analysis proved that PEO and the salts were nearly completely removed from the nanostructure of chitosan, demonstrating that the adopted strategy is successful for producing pure chitosan nanofibers. In addition, the nanofibers obtained after neutralization in ethanol-aqueous solution has better structural stability, at least for six months in aqueous solutions (phosphate buffer (PBS) or water). PMID:27792192

Electrospun PCL/Gelatin composite fibrous scaffolds: mechanical properties and cellular responses.

PubMed

Yao, Ruijuan; He, Jing; Meng, Guolong; Jiang, Bo; Wu, Fang

2016-06-01

Electrospinning of hybrid polymer has gained widespread interest by taking advantages of the biological property of the natural polymer and the mechanical property of the synthetic polymer. However, the effect of the blend ratio on the above two properties has been less reported despite the importance to balance these two properties in various tissue engineering applications. To this aim, we investigated the electrospun PCL/Gelatin composite fibrous scaffolds with different blend ratios of 4:1, 2:1, 1:1, 1:2, 1:4, respectively. The morphology of the electrospun samples was observed by SEM and the result showed that the fiber diameter distribution became more uniform with the increase of the gelatin content. The mechanical testing results indicated that the 2:1 PCL/Gelatin sample had both the highest tensile strength of 3.7 MPa and the highest elongation rate of about 90%. Surprisingly, the 2:1 PCL/Gelatin sample also showed the best mesenchymal stem cell responses in terms of attachment, spreading, and cytoskeleton organization. Such correlation might be partly due to the fact that the enhanced mechanical property, an integral part of the physical microenvironment, likely played an important role in regulating the cellular functions. Overall, our results indicated that the PCL/Gelatin sample with the blend ratio of 2:1 was a superior candidate for scaffolds for tissue engineering applications.

Effect of CO2 levels on nutrient content of lettuce and radish.

PubMed

McKeehen, J D; Smart, D J; Mackowiak, C L; Wheeler, R M; Nielsen, S S

1996-01-01

Atmospheric carbon-dioxide enrichment is known to affect the yield of lettuce and radish grown in controlled environments, but little is known about CO2 enrichment effects on the chemical composition of lettuce and radish. These crops are useful model systems for a Controlled Ecological Life-Support System (CELSS), largely because of their relatively short production cycles. Lettuce (Lactuca sativa L.) cultivar 'Waldmann's Green' and radish (Raphanus sativus L.) cultivar 'Giant White Globe' were grown both in the field and in controlled environments, where hydroponic nutrient solution, light, and temperature were regulated, and where CO2 levels were controlled at 400, 1000, 5000, or 10,000 ppm. Plants were harvested at maturity, dried, and analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate N, free sugars, starch, total dietary fiber, and minerals. Total N, protein N, nonprotein N (NPN), and nitrate N generally increased for radish roots and lettuce leaves when grown under growth chamber conditions compared to field conditions. The nitrate-N level of lettuce leaves, as a percentage of total NPN, decreased with increasing levels of CO2 enrichment. The ash content of radish roots and of radish and lettuce leaves decreased with increasing levels of CO2 enrichment. The levels of certain minerals differed between field- and chamber-grown materials, including changes in the calcium (Ca) and phosphorus (P) contents of radish and lettuce leaves, resulting in reduced Ca/P ratio for chamber-grown materials. The free-sugar contents were similar between the field and chamber-grown lettuce leaves, but total dietary fiber content was much higher in the field-grown plant material. The starch content of growth-chamber lettuce increased with CO2 level.

Effect of CO_2 levels on nutrient content of lettuce and radish

NASA Astrophysics Data System (ADS)

McKeehen, J. D.; Smart, D. J.; Mackowiak, C. L.; Wheeler, R. M.; Nielsen, S. S.

Atmospheric carbon-dioxide enrichment is known to affect the yield of lettuce and radish grown in controlled environments, but little is known about CO_2 enrichment effects on the chemical composition of lettuce and radish. These crops are useful model systems for a Controlled Ecological Life-Support System (CELSS), largely because of their relatively short production cycles. Lettuce (Lactuca sativa L.) cultivar `Waldmann's Green' and radish (Raphanus sativus L.) cultivar `Giant White Globe' were grown both in the field and in controlled environments, where hydroponic nutrient solution, light, and temperature were regulated, and where CO_2 levels were controlled at 400, 1000, 5000, or 10,000 ppm. Plants were harvested at maturity, dried, and analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate N, free sugars, starch, total dietary fiber, and minerals. Total N, protein N, nonprotein N (NPN), and nitrate N generally increased for radish roots and lettuce leaves when grown under growth chamber conditions compared to field conditions. The nitrate-N level of lettuce leaves, as a percentage of total NPN, decreased with increasing levels of CO_2 enrichment. The ash content of radish roots and of radish and lettuce leaves decreased with increasing levels of CO_2 enrichment. The levels of certain minerals differed between field- and chamber-grown materials, including changes in the calcium (Ca) and phosphorus (P) contents of radish roots and lettuce leaves, resulting in reduced Ca/P ratio for chamber-grown materials. The free-sugar contents were similar between the field and chamber-grown lettuce leaves, but total dietary fiber content was much higher in the field-grown plant material. The starch content of growth-chamber lettuce increased with CO_2 level.

Effect of CO2 levels on nutrient content of lettuce and radish

NASA Technical Reports Server (NTRS)

McKeehen, J. D.; Smart, D. J.; Mackowiak, C. L.; Wheeler, R. M.; Nielsen, S. S.; Mitchell, C. A. (Principal Investigator)

1996-01-01

Atmospheric carbon-dioxide enrichment is known to affect the yield of lettuce and radish grown in controlled environments, but little is known about CO2 enrichment effects on the chemical composition of lettuce and radish. These crops are useful model systems for a Controlled Ecological Life-Support System (CELSS), largely because of their relatively short production cycles. Lettuce (Lactuca sativa L.) cultivar 'Waldmann's Green' and radish (Raphanus sativus L.) cultivar 'Giant White Globe' were grown both in the field and in controlled environments, where hydroponic nutrient solution, light, and temperature were regulated, and where CO2 levels were controlled at 400, 1000, 5000, or 10,000 ppm. Plants were harvested at maturity, dried, and analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate N, free sugars, starch, total dietary fiber, and minerals. Total N, protein N, nonprotein N (NPN), and nitrate N generally increased for radish roots and lettuce leaves when grown under growth chamber conditions compared to field conditions. The nitrate-N level of lettuce leaves, as a percentage of total NPN, decreased with increasing levels of CO2 enrichment. The ash content of radish roots and of radish and lettuce leaves decreased with increasing levels of CO2 enrichment. The levels of certain minerals differed between field- and chamber-grown materials, including changes in the calcium (Ca) and phosphorus (P) contents of radish and lettuce leaves, resulting in reduced Ca/P ratio for chamber-grown materials. The free-sugar contents were similar between the field and chamber-grown lettuce leaves, but total dietary fiber content was much higher in the field-grown plant material. The starch content of growth-chamber lettuce increased with CO2 level.

Structural characterization of proteins in wheat flour doughs enriched with intermediate wheatgrass (Thinopyrum intermedium) flour.

PubMed

Marti, Alessandra; Bock, Jayne E; Pagani, Maria Ambrogina; Ismail, Baraem; Seetharaman, Koushik

2016-03-01

The high protein and fiber content of intermediate wheatgrass (IWG) - together with its interesting agronomic traits and environment-related benefits - make this perennial crop attractive also for human consumption. Structural characteristics of the proteins in IWG/hard wheat flour (HWF) doughs (at IWG:HWF ratios of 0:100, 50:50, 75:25 and 100:0) - including aggregate formation, thiols availability, and secondary structure changes during dough mixing - were investigated. Proteins in IWG-doughs had higher solubility and thiol content - as function of IWG content - suggesting that protein network was mostly based on non-covalent interactions. While 50% IWG-enrichment gave an increase in random structures, enrichment at ⩾75% resulted in a decrease in β-sheets with an increase in random structures, indicating a decrease in structural order. The observed differences in protein molecular configuration and interactions in HWF compared to IWG doughs necessitate further investigation to establish their impact on the quality of IWG-enriched bread. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dried plum products as a substitute for phosphate in chicken marinade.

PubMed

Jarvis, Nathan; Clement, Ashley R; O'Bryan, Corliss A; Babu, Dinesh; Crandall, Philip G; Owens, Casey M; Meullenet, Jean-Francois; Ricke, Steven C

2012-06-01

In order to address the growing demand for more natural poultry products, alkaline phosphates commonly used in chicken breast meat marinades were replaced with plum ingredients and evaluated. For initial sensory evaluation, 200 consumers of chicken were served a small portion of the chicken breast on a plate and were asked to evaluate the product for overall impression, flavor, and texture on a 9-point hedonic scale with 1 = "dislike extremely" and 9 = "like extremely." Also, a 5-point just-about-right (JAR) scale was used on questions about tenderness, juiciness, overall flavor, and saltiness. Both hedonic and JAR demonstrated that the marinades of plum concentrate and the blend of plum fiber and powder were not distinguishable from the control (P > 0.05). Using two different percentages of fiber/powder blend, two different percentages of concentrate, sodium tripolyphosphate (STPP), and no marinade, measurements were made for marinade per cent pickup, thaw loss, and cook loss. Plum concentrate at 1.1% was most similar to STPP in marinade per cent pickup, thaw loss, drip loss, and cook loss. These results show that plum ingredients can potentially be used as a substitute in standard phosphate marinades. Consumers are increasingly demanding more natural foods with less artificial additives. This research presents the results of experiments using dried plum ingredients as a substitute for phosphates commonly used in marinades for chicken. Results indicate that dried plum ingredients may be a suitable substitute for phosphates in marinades. Journal of Food Science © 2012 Institute of Food Technologists® No claim to original US government works.

Application of modified hollow fiber liquid phase microextraction in conjunction with chromatography-electron capture detection for quantification of acrylamide in waste water samples at ultra-trace levels.

PubMed

Sobhi, Hamid Reza; Ghambarian, Mahnaz; Behbahani, Mohammad; Esrafili, Ali

2017-03-03

Herein, a simple and sensitive method was successfully developed for the extraction and quantification of acrylamide in water samples. Initially, acrylamide was derivatized through a bromination process. Subsequently, a modified hollow-fiber liquid-phase microextraction was applied for the extraction of the brominated acrylamide from a 10-ml portion of an aqueous sample. Briefly, in this method, the derivatized acrylamide (2,3-dibromopropionamide) was extracted from the aqueous sample into a thin layer of an organic solvent sustained in pores of a porous hollow fiber. Then, it was back-extracted using a small volume of organic acceptor solution (acetonitril, 25μl) located inside the lumen of the hollow fiber followed by gas chromatography-electron capture detection (GC-ECD). The optimal conditions were examined for the extraction of the analyte such as: the organic solvent: dihexyl ether+10% tri-n-octyl phosphine oxide; stirring rate: 750rpm; no salt addition and 30min extraction time. These optimal extraction conditions allowed excellent enrichment factor values for the method. Enrichment factor, detection limit (S/N=3) and dynamic linear range of 60, 2ngL -1 and 50-1000ngL -1 to be determined for the analyte. The relative standard deviations (RSD%) representing precision of the method were in the range of 2.2-5.8 based on the average of three measurements. Accuracy of the method was tested by the relative recovery experiments on spiked samples, with results ranging from 93 to 108%. Finally, the method proved to be simple, rapid, and cost-effective for routine screen of acrylamide-contaminated highly-complicated untreated waste water samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Ion-pair hollow-fiber liquid-phase microextraction of the quaternary ammonium surfactant dicocodimethylammonium chloride.

PubMed

Hultgren, Sofie; Larsson, Niklas; Nilsson, Bo F; Jönsson, Jan Ake

2009-02-01

A two-phase hollow-fiber (HF) liquid-phase microextraction (LPME) method was developed for determination of a quaternary ammonium compound surfactant, dicocodimethylammonium chloride, in aqueous samples. The porous HF was fixed on a metal rod support and was impregnated with approximately 6.6 microL of organic extractant, which was immobilized in the HF pores. Surfactant extraction was facilitated by addition of carboxylic acid to the sample forming neutral ion pairs with the quaternary ammonium compound. After extraction, the analyte was transferred from the organic extractant in the fiber pores by dissolving the 1-octanol into 100 microL methanol. The methanol extract was analyzed by liquid chromatography-mass spectrometry. The method was optimized (with optimized parameters in brackets) with regard to type of organic extractant (1-octanol), fiber length (2 cm), choice and concentration of anionic carrier (600 microg L(-1) octanoate), procedure of transfer to methanol (15-min sonication), sample volume (250 mL), extraction time (17 h), pH (10), and ionic strength (50 mM carbonate). Aspects influencing repeatability in LPME of (quaternary ammonium) surfactants are discussed. The enrichment factor achieved in 250-mL carbonate buffer was around 400. Due to matrix effects, the enrichment factors achieved when industrial process water was analyzed were 120 or about 30% of that in carbonate buffer. Detection limits of 0.3 microg L(-1) in carbonate buffer and 0.9 microg L(-1) in industrial process water were obtained. If the studied compound is seen as a model substance representing quaternary dialkylated dimethylated ammonium surfactants in general, the developed method may be applied to other quaternary ammonium surfactants.

Fermentation of Corn Fiber Hydrolysate to Lactic Acid by the Moderate Thermophile Bacillus coagulans

USDA-ARS?s Scientific Manuscript database

Composted manure from a dairy farm in Texas was examined for thermophilic microorganisms by enrichment in xylose broth medium. Forty randomly picked isolates were identified as strains of Bacillus coagulans by sequence analysis of rRNA genes. One strain, designated as MXL-9, could convert mixed su...

Human Satellite Cell Transplantation and Regeneration from Diverse Skeletal Muscles

PubMed Central

Xu, Xiaoti; Wilschut, Karlijn J.; Kouklis, Gayle; Tian, Hua; Hesse, Robert; Garland, Catharine; Sbitany, Hani; Hansen, Scott; Seth, Rahul; Knott, P. Daniel; Hoffman, William Y.; Pomerantz, Jason H.

2015-01-01

Summary Identification of human satellite cells that fulfill muscle stem cell criteria is an unmet need in regenerative medicine. This hurdle limits understanding how closely muscle stem cell properties are conserved among mice and humans and hampers translational efforts in muscle regeneration. Here, we report that PAX7 satellite cells exist at a consistent frequency of 2–4 cells/mm of fiber in muscles of the human trunk, limbs, and head. Xenotransplantation into mice of 50–70 fiber-associated, or 1,000–5,000 FACS-enriched CD56+/CD29+ human satellite cells led to stable engraftment and formation of human-derived myofibers. Human cells with characteristic PAX7, CD56, and CD29 expression patterns populated the satellite cell niche beneath the basal lamina on the periphery of regenerated fibers. After additional injury, transplanted satellite cells robustly regenerated to form hundreds of human-derived fibers. Together, these findings conclusively delineate a source of bona-fide endogenous human muscle stem cells that will aid development of clinical applications. PMID:26352798

Super-resolution microscopy reveals LINC complex recruitment at nuclear indentation sites.

PubMed

Versaevel, Marie; Braquenier, Jean-Baptiste; Riaz, Maryam; Grevesse, Thomas; Lantoine, Joséphine; Gabriele, Sylvain

2014-12-08

Increasing evidences show that the actin cytoskeleton is a key parameter of the nuclear remodeling process in response to the modifications of cellular morphology. However, detailed information on the interaction between the actin cytoskeleton and the nuclear lamina was still lacking. We addressed this question by constraining endothelial cells on rectangular fibronectin-coated micropatterns and then using Structured Illumination Microscopy (SIM) to observe the interactions between actin stress fibers, nuclear lamina and LINC complexes at a super-resolution scale. Our results show that tension in apical actin stress fibers leads to deep nuclear indentations that significantly deform the nuclear lamina. Interestingly, indented nuclear zones are characterized by a local enrichment of LINC complexes, which anchor apical actin fibers to the nuclear lamina. Moreover, our findings indicate that nuclear indentations induce the formation of segregated domains of condensed chromatin. However, nuclear indentations and condensed chromatin domains are not irreversible processes and both can relax in absence of tension in apical actin stress fibers.

Responses of dietary ileal amino acid digestibility to consumption of different cultivars of potatoes and conventional fibers in grower pigs fed a high-fat basal diet.

PubMed

Wang, Q; Yang, X; Leonard, S; Archbold, T; Sullivan, J A; Duncan, A M; Ma, W D L; Bizimungu, B; Murphy, A; Htoo, J K; Fan, M Z

2012-12-01

Whereas dietary fibers are well recognized for nutritional management of human health issues, fiber is also known to be one of the dietary factors potentially affecting digestive use of dietary proteins. As a staple food, potato (Solanum tuberosum) may be a significant dietary fiber source. The objective of this study was to examine effects of dietary supplementation of six potato cultivar-genotype samples that differ in soluble fiber content and two conventional fiber components (i.e., cellulose and guar gum) on the apparent ileal AA digestibility in pigs fed a high-fat basal diet. The basal diet was formulated as a zero-fiber negative control (NC) to contain 41.5% poultry meal, 4% casein, 15% animal fat-oil blend, 2.8% sucrose, 31% corn (Zea mays) starch, 0.50% salt, and 0.40% trace mineral-vitamin supplement with fat contributing to 47% of the dietary GE. The two fiber diets were formulated by respectively diluting the basal diet with 10% guar gum and 10% cellulose at the expense of corn starch. Six other test diets were formulated by including 8.5% guar gum and further diluting the basal diet with 25.1% one of the six cultivar-genotype samples of dehydrated potato tuber powder to contain about 10% total dietary fiber at the expense of corn starch. Eighty-one 25-kg barrows were fitted with a simple T-cannula at the distal ileum and fed the diets according to a completely randomized block design with each block lasting 28 d. Compared with the NC, the ileal digestibility of Ala, Gly, and Pro were decreased (P < 0.05) by 10% guar gum whereas the digestibility of Gly was reduced (P < 0.05) by 10% cellulose. The ileal digestibility of several AA was decreased (P < 0.05) by the test potatoes plus 8.5% guar gum compared with the NC. Our results suggest that dietary inclusion of fiber at 10% from guar gum and cellulose and contributed by potatoes may adversely affect digestive use of dietary protein.

The effects of fiber enrichment of pasta and fat content on gastric emptying, GLP-1, glucose, and insulin responses to a meal.

PubMed

Frost, G S; Brynes, A E; Dhillo, W S; Bloom, S R; McBurney, M I

2003-02-01

To assess whether the addition of viscous fiber at an amount recommended by the US FDA to allow a 'low saturated fat, cholesterol, soluble fiber and coronary heart disease', health claim label on a food package (1.7 g psyllium) and/or fat (30 g sunflower oil and 3 g sodium propionate) to a pasta meal would affect gastric emptying, postprandial glucose, insulin and GLP-1 concentrations. Ten subjects participated in a two-by-two single blind randomized crossover study. Four meals containing 50 g of available carbohydrate were consumed: pasta with or without psyllium enrichment served with a tomato sauce with (520 kcal per meal) and without (240 kcal per meal) fat. Blood samples were taken for 240 min following the meal and all subjects consumed a buffet meal at the end of the study. Gastric emptying was measured using the paracetamol absorption test. Blood was analysed for glucose, insulin, GLP-1. Visual analog scales were used to record feelings of hunger, pleasantness and nausea. The psyllium-enriched pasta had no significant effect on gastric emptying or the incremental area under the curve (IAUC) for GLP-1, insulin or glucose compared with the control pasta. The addition of polyunsaturated fat and sodium propionate significantly increased the IAUC for GLP-1 (P<0.001), delaying gastric emptying (P<0.002), and decreasing glucose (P<0.002). A dose of 1.7 g psyllium did not evoke measurable effects on gastric emptying, postprandial GLP-1, insulin or glucose metabolism. However the addition of 30 g of oil and 3 g of sodium propionate to the pasta did reduce gastric emptying, increase GLP-1 and reduce glucose and insulin concentrations. While this short-term study may have implications in terms of reducing the risk of diabetes and improving coronary risk factor profiles the long term effects of these nutrients need to be studied.

Polyester projects for India, Pakistan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siddiqi, R.

1993-02-10

India's Indo Rama Synthetics (Bombay) is planning a $186-million integrated polyester fiber and filament complex at Nagpur, Maharashtra. The complex will have annual capacities for 38,000 m.t. of polyester chips by polycondensation, 25,000 m.t. of polyester staple fiber, and 12,000 m.t. of polyester blended yarn. The company is negotiating with the main world suppliers of polycondensation technology. The first stage of the project is slated to begin production by the end of this year and be fully completed by 1994. In Pakistan, National Fibers Ltd. (PNF; Karachi) has signed a deal with Zimmer (Frankfurt) for technology, procurement, construction, and supportmore » work to expand polyester staple fiber capacity from 14,000 m.t./year to 52,000 m.t./year. The technology involves a continuous polymerization process. The project also calls for improvements to PNF's existing batch plant. It is scheduled for completion by the end of 1994. Total cost of the project is estimated at Rs1.745 billion ($70 million), out of which the foreign exchange component is Rs1.05 billion. The Islamic Development Bank (Jeddah; Saudi Arabia) has already approved a $27-million slice of the financing, while the balance of the foreign exchange loan is being arranged through suppliers credit. Local currency loans will be provided by other financial institutions in Pakistan.« less

Effect of weight fraction of carbon black and number of plies of E-glass fiber to reflection loss of E-glass/ripoxy composite for radar absorbing structure (RAS)

NASA Astrophysics Data System (ADS)

Widyastuti, Ramadhan, Rizal; Ardhyananta, Hosta; Zainuri, Mochamad

2013-09-01

Nowadays, studies on investigating radar absorbing structure (RAS) using fiber reinforced polymeric (FRP) composite materials are becoming popular research field because the electromagnetic properties of FRP composites can be tailored effectively by just adding some electromagnetic powders, such as carbon black, ferrite, carbonyl iron, and etc., to the matrix of composites. The RAS works not only as a load bearing structure to hold the antenna system, but also has the important function of absorbing the in-band electromagnetic wave coming from the electromagnetic energy of tracking systems. In this study, E-glass fiber reinforced ripoxy resin composite was fabricated by blending the conductive carbon black (Ketjenblack EC300J) with the binder matrix of the composite material and maximizing the coefficient of absorption more than 90% (more than -10 dB) within the X-band frequency (8 - 12 GHz). It was measured by electrical conductivity (LCR meter) and vector network analyzer (VNA). Finally, the composite RAS with 0.02 weight fraction of carbon black and 4 plies of E-glass fiber showed thickness of 2.1 mm, electrical conductivity of 8.33 × 10-6 S/m, and maximum reflection loss of -27.123 dB, which can absorb more than 90% of incident EM wave throughout the entire X-band frequency range, has been developed.

Theranostic 3-Dimensional nano brain-implant for prolonged and localized treatment of recurrent glioma

NASA Astrophysics Data System (ADS)

Ramachandran, Ranjith; Junnuthula, Vijayabhaskar Reddy; Gowd, G. Siddaramana; Ashokan, Anusha; Thomas, John; Peethambaran, Reshmi; Thomas, Anoop; Unni, Ayalur Kodakara Kochugovindan; Panikar, Dilip; Nair, Shantikumar V.; Koyakutty, Manzoor

2017-03-01

Localized and controlled delivery of chemotherapeutics directly in brain-tumor for prolonged periods may radically improve the prognosis of recurrent glioblastoma. Here, we report a unique method of nanofiber by fiber controlled delivery of anti-cancer drug, Temozolomide, in orthotopic brain-tumor for one month using flexible polymeric nano-implant. A library of drug loaded (20 wt%) electrospun nanofiber of PLGA-PLA-PCL blends with distinct in vivo brain-release kinetics (hours to months) were numerically selected and a single nano-implant was formed by co-electrospinning of nano-fiber such that different set of fibres releases the drug for a specific periods from days to months by fiber-by-fiber switching. Orthotopic rat glioma implanted wafers showed constant drug release (116.6 μg/day) with negligible leakage into the peripheral blood (<100 ng) rendering ~1000 fold differential drug dosage in tumor versus peripheral blood. Most importantly, implant with one month release profile resulted in long-term (>4 month) survival of 85.7% animals whereas 07 day releasing implant showed tumor recurrence in 54.6% animals, rendering a median survival of only 74 days. In effect, we show that highly controlled drug delivery is possible for prolonged periods in orthotopic brain-tumor using combinatorial nanofibre libraries of bulk-eroding polymers, thereby controlling glioma recurrence.

Soybean-Enriched Snacks Based on African Rice

PubMed Central

Marengo, Mauro; Akoto, Hannah F.; Zanoletti, Miriam; Carpen, Aristodemo; Buratti, Simona; Benedetti, Simona; Barbiroli, Alberto; Johnson, Paa-Nii T.; Sakyi-Dawson, Esther O.; Saalia, Firibu K.; Bonomi, Francesco; Pagani, Maria Ambrogina; Manful, John; Iametti, Stefania

2016-01-01

Snacks were produced by extruding blends of partially-defatted soybean flour with flours from milled or parboiled African-grown rice. The interplay between composition and processing in producing snacks with a satisfactory sensory profile was addressed by e-sensing, and by molecular and rheological approaches. Soybean proteins play a main role in defining the properties of the protein network in the products. At the same content in soybean flour, use of parboiled rice flour increases the snack’s hardness. Electronic nose and electronic tongue discriminated samples containing a higher amount of soybean flour from those with a lower soybean flour content. PMID:28231133

Soybean-Enriched Snacks Based on African Rice.

PubMed

Marengo, Mauro; Akoto, Hannah F; Zanoletti, Miriam; Carpen, Aristodemo; Buratti, Simona; Benedetti, Simona; Barbiroli, Alberto; Johnson, Paa-Nii T; Sakyi-Dawson, Esther O; Saalia, Firibu K; Bonomi, Francesco; Pagani, Maria Ambrogina; Manful, John; Iametti, Stefania

2016-05-20

Snacks were produced by extruding blends of partially-defatted soybean flour with flours from milled or parboiled African-grown rice. The interplay between composition and processing in producing snacks with a satisfactory sensory profile was addressed by e-sensing, and by molecular and rheological approaches. Soybean proteins play a main role in defining the properties of the protein network in the products. At the same content in soybean flour, use of parboiled rice flour increases the snack's hardness. Electronic nose and electronic tongue discriminated samples containing a higher amount of soybean flour from those with a lower soybean flour content.

Tailored interphase structure for improved strength and energy absorption of composites

NASA Astrophysics Data System (ADS)

Gao, Xiao

Fiber reinforced polymeric composites are lightweight, high-strength and high impact-resistant materials used widely for various applications. It has been shown that the mechanical performance of composites are dependent on the interphase, a three-dimensional region of nanometer size in the vicinity of the fiber-matrix boundary that possesses properties different from those of either the fiber reinforcement or the matrix resin and governs the load transfer from matrix to fiber. This research conducts a systematic study on glass fiber-epoxy interphase structure by tailoring adhesion between constituents and the creation of textures to control strength and energy absorption through mechanical interlocking between glass fiber and epoxy matrix. Our objective is to establish the foundation for microstructural design and optimization of the composite's structural and impact performance. Two ways of roughening the glass fiber surface have been studied to create the mechanical interlocking between fiber and resin; the first technique involves forming in-situ islands on the glass fiber surface by using silane blends of Glycidoxypropyltrimethoxy silane (GPS) and Tetraethoxy silane (TEOS); the second technique applies a silane coupling agents based sizing with the incorporation of silica nanoparticles (Ludox TMA, 22 nm) onto the fiber surface. The microdroplet test was selected to characterize the influence of adhesion and mechanical interlocking effects on interphase properties of different sizing sized glass fiber reinforced epoxy systems. A suitable data reduction scheme enables the strength and specified energy absorbed due to debonding, dynamic sliding, and quasi-static sliding to be quantified. In order to validate the effect of tailored interphase structure, which is induced by creating mechanical interlocking between fiber and resin, on macroscopic composite properties, composite panels were made from these four different sizing sized glass fibers and tested using the punch shear test. The composite panel made from the hybrid sizing sized glass fiber exhibited improved strength and energy absorption consistent with the trends in micromechanical measurements. Through all failure stages under macromechanical testing, hybrid sizing sized glass fiber/epoxyamine composite panel shows an increase in the strength and total energy absorption by 13% and 26%, respectively, compared to the compatible sizing sized baseline. Both micromechanical and macromechanical tests demonstrate the significant influence of tailoring the interphase structure on improving the impact performance of the composites. The hybrid sizing with the incorporation of nanoparticles, in particular, can greatly improve the impact resistance (i.e. energy absorption) of composites without sacrificing its structural performance (i.e. strength).

Synthesis and Characterization of a Polyimide-Epoxy Composite for Dental Applications

NASA Astrophysics Data System (ADS)

Yang, An; Xu, Chun

2018-03-01

Epoxy (EP) resins have been employed in dentistry for years, but their intrinsic brittleness demands a reinforcement to make them an ideal dental material that combines strength, toughness, and aesthetics. In this study, an EP resin was reinforced with a low-molecular-weight polyimide (PI). The PI/EP composites were subjected to three-point bending tests and examined by the scanning electron microscopy. It was found that blending PI with EP in proper proportions strengthened EP without sacrificing its toughness. The PI/EP composite could be employed in dentistry as the matrix of fiber-reinforced dental root canal posts.

Assessment of microbial communities associated with fermentative-methanogenic biodegradation of aromatic hydrocarbons in groundwater contaminated with a biodiesel blend (B20).

PubMed

Ramos, Débora Toledo; da Silva, Márcio Luís Busi; Nossa, Carlos Wolfgang; Alvarez, Pedro J J; Corseuil, Henry Xavier

2014-09-01

A controlled field experiment was conducted to assess the potential for fermentative-methanogenic biostimulation (by ammonium-acetate injection) to enhance biodegradation of benzene, toluene, ethylbenzene and xylenes (BTEX) as well as polycyclic aromatic hydrocarbons (PAHs) in groundwater contaminated with biodiesel B20 (20:80 v/v soybean biodiesel and diesel). Changes in microbial community structure were assessed by pyrosequencing 16S rRNA analyses. BTEX and PAH removal began 0.7 year following the release, concomitantly with the increase in the relative abundance of Desulfitobacterium and Geobacter spp. (from 5 to 52.7 % and 15.8 to 37.3 % of total Bacteria 16S rRNA, respectively), which are known to anaerobically degrade hydrocarbons. The accumulation of anaerobic metabolites acetate and hydrogen that could hinder the thermodynamic feasibility of BTEX and PAH biotransformations under fermentative/methanogenic conditions was apparently alleviated by the growing predominance of Methanosarcina. This suggests the importance of microbial population shifts that enrich microorganisms capable of interacting syntrophically to enhance the feasibility of fermentative-methanogenic bioremediation of biodiesel blend releases.

The miRNA Transcriptome Directly Reflects the Physiological and Biochemical Differences between Red, White, and Intermediate Muscle Fiber Types

PubMed Central

Ma, Jideng; Wang, Hongmei; Liu, Rui; Jin, Long; Tang, Qianzi; Wang, Xun; Jiang, Anan; Hu, Yaodong; Li, Zongwen; Zhu, Li; Li, Ruiqiang; Li, Mingzhou; Li, Xuewei

2015-01-01

MicroRNAs (miRNAs) are small non-coding RNAs that can regulate their target genes at the post-transcriptional level. Skeletal muscle comprises different fiber types that can be broadly classified as red, intermediate, and white. Recently, a set of miRNAs was found expressed in a fiber type-specific manner in red and white fiber types. However, an in-depth analysis of the miRNA transcriptome differences between all three fiber types has not been undertaken. Herein, we collected 15 porcine skeletal muscles from different anatomical locations, which were then clearly divided into red, white, and intermediate fiber type based on the ratios of myosin heavy chain isoforms. We further illustrated that three muscles, which typically represented each muscle fiber type (i.e., red: peroneal longus (PL), intermediate: psoas major muscle (PMM), white: longissimus dorsi muscle (LDM)), have distinct metabolic patterns of mitochondrial and glycolytic enzyme levels. Furthermore, we constructed small RNA libraries for PL, PMM, and LDM using a deep sequencing approach. Results showed that the differentially expressed miRNAs were mainly enriched in PL and played a vital role in myogenesis and energy metabolism. Overall, this comprehensive analysis will contribute to a better understanding of the miRNA regulatory mechanism that achieves the phenotypic diversity of skeletal muscles. PMID:25938964

Novel biocompatible polymeric blends for bone regeneration: Material and matrix design and development

NASA Astrophysics Data System (ADS)

Deng, Meng

The first part of the work presented in this dissertation is focused on the design and development of novel miscible and biocompatible polyphosphazene-polyester blends as candidate materials for scaffold-based bone tissue engineering applications. Biodegradable polyesters such as poly(lactide-co-glycolide) (PLAGA) are among the most widely used polymeric materials for bone tissue engineering. However, acidic degradation products resulting from the bulk degradation mechanism often lead to catastrophic failure of the structure integrity, and adversely affect biocompatibility both in vitro and in vivo. One promising approach to circumvent these limitations is to blend PLAGA with other macromolecules that can buffer the acidic degradation products with a controlled degradation rate. Biodegradable polyphosphazenes (PPHOS), a new class of biomedical materials, have proved to be superior candidate materials to achieve this objective due to their unique buffering degradation products. A highly practical blending approach was adopted to develop novel biocompatible, miscible blends of these two polymers. In order to achieve this miscibility, a series of amino acid ester, alkoxy, aryloxy, and dipeptide substituted PPHOS were synthesized to promote hydrogen bonding interactions with PLAGA. Five mixed-substituent PPHOS compositions were designed and blended with PLAGA at different weight ratios producing candidate blends via a mutual solvent method. Preliminary characterization identified two specific side groups namely glycylglycine dipeptide and phenylphenoxy that resulted in improved blend miscibility and enhanced in vitro osteocompatibility. These findings led to the synthesis of a mixed-substituent polyphosphazene poly[(glycine ethyl glycinato)1(phenylphenoxy)1phosphazene] (PNGEGPhPh) for blending with PLAGA. Two dipeptide-based blends having weight ratios of PNGEGPhPh to PLAGA namely 25:75 (Matrix1) and 50:50 (Matrix2) were fabricated. Both of the blends were characterized for miscibility, mechanical properties, degradation kinetics, and in vitro osteocompatibility. Primary rat osteoblasts (PRO) isolated from rat calvaria were used to evaluate their in vitro osteocompatibility. The blends were also characterized for in vivo biodegradability and biocompatibility using a rat subcutaneous implantation model. Successful in vivo scaffold-based tissue regeneration greatly depends on the scaffold material biocompatibility, mechanical stability, and scaffold architecture to promote tissue in-growth. The other part of the work in the dissertation is focused on the development of mechanically competent bioresorbable nano-structured three-dimensional (3D) hiomimetic scaffolds for bone tissue engineering applications. Scaffold material selection was based on achieving improved mechanical stability, in vitro osteoblast performance, and in vivo biocompatibility. A miscible PNGEGPhPh-PLAGA blend system developed and characterized in the first part of the thesis work was chosen to fabricate a nanofiber-based mechanically competent biomimetic scaffold via electrospinning. Due to its versatility, controllability and reproducibility, the technique of electrospinning was adopted to produce blend nanofibers. The polymer solution concentration and electrospinning parameters were optimized to produce blend fibers in the range of 50-500 nm to mimic dimensions of collagen fibrils present in the natural extracellular matrix of native bone. These blend nanofiber matrices supported PRO adhesion, proliferation and showed an elevated phenotype expression compared to PLAGA nanofibers. Orienting electrospun nanofibers in a concentric manner with an open central cavity created a mechanically competent 3D scaffold mimicking the bone marrow cavity, as well as, the lamellar structure of bone. The 3D biomimetic scaffold exhibited a similar characteristic mechanical behavior to that of native bone. Compressive modulus of the scaffold was found to be within the range of human trabecular bone. To our knowledge this is the first mechanically competent 3D electrospun nanofiber scaffold with mechanical properties in the middle range of human trabecular bone. The potential of this scaffold for bone repair was further investigated by monitoring the cellular activity and mechanical performance over time using in vitro culture. This biomimetic scaffold supported the robust PRO growth throughout the scaffold architecture and maintained osteoblast phenotype expression in vitro, which resulted in a similar cell-matrix organization to that of native bone and maintenance of structure integrity. (Abstract shortened by UMI.)

Carbon Fibers from Chicken Feather Keratin

NASA Astrophysics Data System (ADS)

Miller, Melissa E.; Wool, Richard

2006-03-01

As the availability of synthetic and fossil-fuel based resources is becoming limited, bio-based materials offer an environmentally friendly alternative. Chicken feathers remain a huge agricultural waste. The feathers are comprised of approximately 97% keratin, but are currently used only to enrich animal feed. However, this usage is becoming a problem with the spread of diseases such as Bovine Spongiform Encephalopathy, commonly called ``Mad Cow Disease.'' The hollow, microcrystalline, oriented keratin feather fibers offer a novel, low cost approach to producing carbon fibers through controlled pyrolysis. Carbonized feather fibers (CFF) were prepared by first heating to 225 ^oC (below the melting point)in N2 for 26 hours to crosslink and stabilize the fiber structure; then carbonization occurred by increasing the temperature to 450 ^oC for two more hours. The resulting CFF were hollow, stiff and strong and had an affine 80% weight loss, which is near the theoretical value for the C-content of keratin. Initial studies showed that a composite with the CFF and an epoxidized soybean oil (AESO) gave an improved fiber modulus ECFF of order 13.5--66.1 GPa. With continued research, the goals are to increase the stiffness of the feathers to 100 GPa, while increasing the strength in the range of 5-10 GPa.

Cotton fiber tips have diverse morphologies and show evidence of apical cell wall synthesis

PubMed Central

Stiff , Michael R.; Haigler, Candace H.

2016-01-01

Cotton fibers arise through highly anisotropic expansion of a single seed epidermal cell. We obtained evidence that apical cell wall synthesis occurs through examining the tips of young elongating Gossypium hirsutum (Gh) and G. barbadense (Gb) fibers. We characterized two tip types in Gh fiber (hemisphere and tapered), each with distinct apical diameter, central vacuole location, and distribution of cell wall components. The apex of Gh hemisphere tips was enriched in homogalacturonan epitopes, including a relatively high methyl-esterified form associated with cell wall pliability. Other wall components increased behind the apex including cellulose and the α-Fuc-(1,2)-β-Gal epitope predominantly found in xyloglucan. Gb fibers had only one narrow tip type featuring characters found in each Gh tip type. Pulse-labeling of cell wall glucans indicated wall synthesis at the apex of both Gh tip types and in distal zones. Living Gh hemisphere and Gb tips ruptured preferentially at the apex upon treatment with wall degrading enzymes, consistent with newly synthesized wall at the apex. Gh tapered tips ruptured either at the apex or distantly. Overall, the results reveal diverse cotton fiber tip morphologies and support primary wall synthesis occurring at the apex and discrete distal regions of the tip. PMID:27301434

The miRNA Transcriptome Directly Reflects the Physiological and Biochemical Differences between Red, White, and Intermediate Muscle Fiber Types.

PubMed

Ma, Jideng; Wang, Hongmei; Liu, Rui; Jin, Long; Tang, Qianzi; Wang, Xun; Jiang, Anan; Hu, Yaodong; Li, Zongwen; Zhu, Li; Li, Ruiqiang; Li, Mingzhou; Li, Xuewei

2015-04-29

MicroRNAs (miRNAs) are small non-coding RNAs that can regulate their target genes at the post-transcriptional level. Skeletal muscle comprises different fiber types that can be broadly classified as red, intermediate, and white. Recently, a set of miRNAs was found expressed in a fiber type-specific manner in red and white fiber types. However, an in-depth analysis of the miRNA transcriptome differences between all three fiber types has not been undertaken. Herein, we collected 15 porcine skeletal muscles from different anatomical locations, which were then clearly divided into red, white, and intermediate fiber type based on the ratios of myosin heavy chain isoforms. We further illustrated that three muscles, which typically represented each muscle fiber type (i.e., red: peroneal longus (PL), intermediate: psoas major muscle (PMM), white: longissimus dorsi muscle (LDM)), have distinct metabolic patterns of mitochondrial and glycolytic enzyme levels. Furthermore, we constructed small RNA libraries for PL, PMM, and LDM using a deep sequencing approach. Results showed that the differentially expressed miRNAs were mainly enriched in PL and played a vital role in myogenesis and energy metabolism. Overall, this comprehensive analysis will contribute to a better understanding of the miRNA regulatory mechanism that achieves the phenotypic diversity of skeletal muscles.

Silica-based ionogels: nanoconfined ionic liquid-rich fibers for headspace solid-phase microextraction coupled with gas chromatography-barrier discharge ionization detection.

PubMed

Pena-Pereira, Francisco; Marcinkowski, Lukasz; Kloskowski, Adam; Namieśnik, Jacek

2014-12-02

In this work, hybrid silica-based materials with immobilized ionic liquids (ILs) were prepared by sol-gel technology and evaluated as solid-phase microextraction (SPME) fiber coatings. High loadings of the IL 1-methyl-3-butylimidazolium bis(trifluoromethylsulfonyl)imide ([C4MIM][TFSI]) were confined within the hybrid network. Coatings composition and morphology were evaluated using scanning electron microscopy and energy dispersive X-ray spectrometry. The obtained ionogel SPME fibers exhibited high extractability for aromatic volatile compounds, yielding good sensitivity and precision when combined with a gas chromatograph with barrier ionization discharge (GC-BID) detection. A central composite design was used for assessing the effect of experimental parameters on the extraction process. Under optimized conditions, the proposed ionogel SPME fiber coatings enabled the achievement of excellent enrichment factors (up to 7400). The limits of detection (LODs) were found in the range 0.03-1.27 μg L(-1), whereas the repeatability and fiber-to-fiber reproducibility were 5.6% and 12.0% on average, respectively. Water samples were analyzed by the proposed methodology, showing recovery values in the range of 88.7-113.9%. The results obtained in this work suggest that ionogels can be promising coating materials for future applications of SPME and related sample preparation techniques.

Physics Teacher Candidates' Opinions on Fiber Optics and New Technologies in This Field

ERIC Educational Resources Information Center

Çildir, Sema

2016-01-01

Factors such as innovations brought in by the developing technology, also rapidly changing social structures casted various roles to both the student and the teacher. Therefore, it is necessary to associate such knowledge acquired in courses with implications of the knowledge in our real lives and to constantly enrich course contents, namely to…

Red:far-red light conditions affect the emission of volatile organic compounds from barley (Hordeum vulgare), leading to altered biomass allocation in neighbouring plants

PubMed Central

Kegge, Wouter; Ninkovic, Velemir; Glinwood, Robert; Welschen, Rob A. M.; Voesenek, Laurentius A. C. J.; Pierik, Ronald

2015-01-01

Background and Aims Volatile organic compounds (VOCs) play various roles in plant–plant interactions, and constitutively produced VOCs might act as a cue to sense neighbouring plants. Previous studies have shown that VOCs emitted from the barley (Hordeum vulgare) cultivar ‘Alva’ cause changes in biomass allocation in plants of the cultivar ‘Kara’. Other studies have shown that shading and the low red:far-red (R:FR) conditions that prevail at high plant densities can reduce the quantity and alter the composition of the VOCs emitted by Arabidopsis thaliana, but whether this affects plant–plant signalling remains unknown. This study therefore examines the effects of far-red light enrichment on VOC emissions and plant–plant signalling between ‘Alva’ and ‘Kara’. Methods The proximity of neighbouring plants was mimicked by supplemental far-red light treatment of VOC emitter plants of barley grown in growth chambers. Volatiles emitted by ‘Alva’ under control and far-red light-enriched conditions were analysed using gas chromatography–mass spectrometry (GC-MS). ‘Kara’ plants were exposed to the VOC blend emitted by the ‘Alva’ plants that were subjected to either of the light treatments. Dry matter partitioning, leaf area, stem and total root length were determined for ‘Kara’ plants exposed to ‘Alva’ VOCs, and also for ‘Alva’ plants exposed to either control or far-red-enriched light treatments. Key Results Total VOC emissions by ‘Alva’ were reduced under low R:FR conditions compared with control light conditions, although individual volatile compounds were found to be either suppressed, induced or not affected by R:FR. The altered composition of the VOC blend emitted by ‘Alva’ plants exposed to low R:FR was found to affect carbon allocation in receiver plants of ‘Kara’. Conclusions The results indicate that changes in R:FR light conditions influence the emissions of VOCs in barley, and that these altered emissions affect VOC-mediated plant–plant interactions. PMID:25851141

Red:far-red light conditions affect the emission of volatile organic compounds from barley (Hordeum vulgare), leading to altered biomass allocation in neighbouring plants.

PubMed

Kegge, Wouter; Ninkovic, Velemir; Glinwood, Robert; Welschen, Rob A M; Voesenek, Laurentius A C J; Pierik, Ronald

2015-05-01

Volatile organic compounds (VOCs) play various roles in plant-plant interactions, and constitutively produced VOCs might act as a cue to sense neighbouring plants. Previous studies have shown that VOCs emitted from the barley (Hordeum vulgare) cultivar 'Alva' cause changes in biomass allocation in plants of the cultivar 'Kara'. Other studies have shown that shading and the low red:far-red (R:FR) conditions that prevail at high plant densities can reduce the quantity and alter the composition of the VOCs emitted by Arabidopsis thaliana, but whether this affects plant-plant signalling remains unknown. This study therefore examines the effects of far-red light enrichment on VOC emissions and plant-plant signalling between 'Alva' and 'Kara'. The proximity of neighbouring plants was mimicked by supplemental far-red light treatment of VOC emitter plants of barley grown in growth chambers. Volatiles emitted by 'Alva' under control and far-red light-enriched conditions were analysed using gas chromatography-mass spectrometry (GC-MS). 'Kara' plants were exposed to the VOC blend emitted by the 'Alva' plants that were subjected to either of the light treatments. Dry matter partitioning, leaf area, stem and total root length were determined for 'Kara' plants exposed to 'Alva' VOCs, and also for 'Alva' plants exposed to either control or far-red-enriched light treatments. Total VOC emissions by 'Alva' were reduced under low R:FR conditions compared with control light conditions, although individual volatile compounds were found to be either suppressed, induced or not affected by R:FR. The altered composition of the VOC blend emitted by 'Alva' plants exposed to low R:FR was found to affect carbon allocation in receiver plants of 'Kara'. The results indicate that changes in R:FR light conditions influence the emissions of VOCs in barley, and that these altered emissions affect VOC-mediated plant-plant interactions. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Industrial scale-up of pH-controlled liquid hot water pretreatment of corn fiber for fuel ethanol production.

PubMed

Mosier, Nathan S; Hendrickson, Richard; Brewer, Mark; Ho, Nancy; Sedlak, Miroslav; Dreshel, Richard; Welch, Gary; Dien, Bruce S; Aden, Andy; Ladisch, Michael R

2005-05-01

The pretreatment of cellulose in corn fiber by liquid hot water at 160 degrees C and a pH above 4.0 dissolved 50% of the fiber in 20 min. The pretreatment also enabled the subsequent complete enzymatic hydrolysis of the remaining polysaccharides to monosaccharides. The carbohydrates dissolved by the pretreatment were 80% soluble oligosaccharides and 20% monosaccharides with <1% of the carbohydrates lost to degradation products. Only a minimal amount of protein was dissolved, thus enriching the protein content of the undissolved material. Replication of laboratory results in an industrial trial at 43 gallons per minute (163 L/min) of fiber slurry with a residence time of 20 min illustrates the utility and practicality of this approach for pretreating corn fiber. The added costs owing to pretreatment, fiber, and hydrolysis are equivalent to less than 0.84 dollars/gal of ethanol produced from the fiber. Minimizing monosaccharide formation during pretreatment minimized the formation of degradation products; hence, the resulting sugars were readily fermentable to ethanol by the recombinant hexose and by pentose-fermenting Saccharomyces cerevisiae 424A(LNH-ST) and ethanologenic Escherichia coli at yields >90% of theoretical based on the starting fiber. This cooperative effort and first successful trial opens the door for examining the robustness of the pretreatment system under extended run conditions as well as pretreatment of other cellulose-containing materials using water at controlled pH.