Electron processing of fibre-reinforced advanced composites

Energy Technology Data Exchange (ETDEWEB)

Singh, A.; Saunders, C.B.; Barnard, J.W.; Lopata, V.J.; Kremers, W.; McDougall, T.E.; Chung, M.; Tateishi, Miyoko [Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs.

1996-08-01

Advanced composites, such as carbon-fibre-reinforced epoxies, are used in the aircraft, aerospace, sporting goods, and transportation industries. Though thermal curing is the dominant industrial process for advanced composites, electron curing of similar composites containing acrylated epoxy matrices has been demonstrated by our work. The main attraction of electron processing technology over thermal technology is the advantages it offers which include ambient temperature curing, reduced curing times, reduced volatile emissions, better material handling, and reduced costs. Electron curing technology allows for the curing of many types of products, such as complex shaped, those containing different types of fibres and up to 15 cm thick. Our work has been done principally with the AECL`s 10 MeV, 1 kW electron accelerator; we have also done some comparative work with an AECL Gammacell 220. In this paper we briefly review our work on the various aspects of electron curing of advanced composites and their properties. (Author).

New type of chitosan/2-hydroxypropyl-β-cyclodextrin composite membrane for gallic acid encapsulation and controlled release.

Science.gov (United States)

Paun, Gabriela; Neagu, Elena; Tache, Andreia; Radu, G L

2014-01-01

A new type of chitosan/2-hydroxypropyl-β-cyclodextrin composite membrane have been developed for the encapsulation and controlled release of gallic acid. The morphology of the composite membrane was investigated by infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM), whereas swelling gallic acid and release properties were investigated by UV-visible spectroscopy. The release behavior with pH changes was also explored. The composite membrane based on chitosan/2-hydroxypropyl-β-cyclodextrin with gallic acid included showed improved antioxidant capacities compared to plain chitosan membrane. The information obtained in this study will facilitate the design and preparation of composite membrane based on chitosan and could open a wide range of applications, particularly its use as an antioxidant in food, food packaging, biomedical (biodegradable soft porous scaffolds for enhance the surrounding tissue regeneration), pharmaceutical and cosmetics industries.

Organosulfonic acid-functionalized mesoporous composites based on natural rubber and hexagonal mesoporous silica

Energy Technology Data Exchange (ETDEWEB)

Nuntang, Sakdinun; Poompradub, Sirilux [Fuels Research Center, Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Patumwan, Bangkok 10330 (Thailand); Butnark, Suchada [PTT Research and Technology Institute, PTT Public Company Limited, Wangnoi, Ayutthaya 13170 (Thailand); Yokoi, Toshiyuki; Tatsumi, Takashi [Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503 (Japan); Ngamcharussrivichai, Chawalit, E-mail: Chawalit.Ng@Chula.ac.th [Fuels Research Center, Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Patumwan, Bangkok 10330 (Thailand); Center of Excellence on Petrochemical and Materials Technology (PETROMAT), Chulalongkorn University, Patumwan, Bangkok 10330 (Thailand)

2014-10-15

This study is the first report on synthesis, characterization and catalytic application of propylsulfonic acid-functionalized mesoporous composites based on natural rubber (NR) and hexagonal mesoporous silica (HMS). In comparison with propylsulfonic acid-functionalized HMS (HMS-SO{sub 3}H), a series of NR/HMS-SO{sub 3}H composites were prepared via an in situ sol–gel process using tetrahydrofuran as the synthesis media. Tetraethylorthosilicate as the silica source, was simultaneously condensed with 3-mercaptopropyltrimethoxysilane in a solution of NR followed by oxidation with hydrogen peroxide to achieve the mesoporous composites containing propylsulfonic acid groups. Fourier-transform infrared spectroscopy and {sup 29}Si MAS nuclear magnetic resonance spectroscopy results verified that the silica surfaces of the NR/HMS-SO{sub 3}H composites were functionalized with propylsulfonic acid groups and covered with NR molecules. After the incorporation of NR and organo-functional group into HMS, the hexagonal mesostructure remained intact concomitantly with an increased framework wall thickness and unit cell size, as evidenced by the X-ray powder diffraction analysis. Scanning electron microscopy analysis indicated a high interparticle porosity of NR/HMS-SO{sub 3}H composites. The textural properties of NR/HMS-SO{sub 3}H were affected by the amount of MPTMS loading to a smaller extent than that of HMS-SO{sub 3}H. NR/HMS-SO{sub 3}H exhibited higher hydrophobicity than HMS-SO{sub 3}H, as revealed by H{sub 2}O adsorption–desorption measurements. Moreover, the NR/HMS-SO{sub 3}H catalysts possessed a superior specific activity to HMS-SO{sub 3}H in the esterification of lauric acid with ethanol, resulting in a higher conversion level. - Highlights: • Acidic NR/HMS-SO{sub 3}H composites were prepared by in situ sol–gel process. • Propylsulfonic acid was functionalized onto HMS surface by direct co-condensation. • NR/HMS-SO{sub 3}H exhibited a hexagonal

Composition quantification of electron-transparent samples by backscattered electron imaging in scanning electron microscopy

Energy Technology Data Exchange (ETDEWEB)

Müller, E., E-mail: erich.mueller@kit.edu; Gerthsen, D.

2017-02-15

The contrast of backscattered electron (BSE) images in scanning electron microscopy (SEM) depends on material parameters which can be exploited for composition quantification if some information on the material system is available. As an example, the In-concentration in thin In{sub x}Ga{sub 1−x}As layers embedded in a GaAs matrix is analyzed in this work. The spatial resolution of the technique is improved by using thin electron-transparent specimens instead of bulk samples. Although the BSEs are detected in a comparably small angular range by an annular semiconductor detector, the image intensity can be evaluated to determine the composition and local thickness of the specimen. The measured intensities are calibrated within one single image to eliminate the influence of the detection and amplification system. Quantification is performed by comparison of experimental and calculated data. Instead of using time-consuming Monte-Carlo simulations, an analytical model is applied for BSE-intensity calculations which considers single electron scattering and electron diffusion. - Highlights: • Sample thickness and composition are quantified by backscattered electron imaging. • A thin sample is used to achieve spatial resolution of few nanometers. • Calculations are carried out with a time-saving electron diffusion model. • Small differences in atomic number and density detected at low electron energies.

Graphene oxide reinforced poly (4-styrenesulfonic acid)/polyvinyl alcohol blend composites with enhanced dielectric properties for portable and flexible electronics

Energy Technology Data Exchange (ETDEWEB)

Deshmukh, Kalim, E-mail: deshmukh.kalim@gmail.com [Department of Physics, B.S. Abdur Rahman University, Chennai, 600048, TN (India); Ahamed, M. Basheer [Department of Physics, B.S. Abdur Rahman University, Chennai, 600048, TN (India); Sadasivuni, Kishor Kumar [Mechanical and Industrial Engineering Department, Qatar University, P.O. Box 2713, Doha (Qatar); Ponnamma, Deepalekshmi; AlMaadeed, Mariam Al-Ali [Center for Advanced Materials, Qatar University, P.O. Box 2713, Doha (Qatar); Khadheer Pasha, S.K. [Department of Physics, School of Advanced Sciences, VIT University, Vellore, 632014, TN (India); Deshmukh, Rajendra R. [Department of Physics, Institute of Chemical Technology, Matunga, Mumbai, 400019 (India); Chidambaram, K. [Department of Physics, School of Advanced Sciences, VIT University, Vellore, 632014, TN (India)

2017-01-15

In this work, Graphene Oxide (GO) reinforced novel polymer composites comprising of poly (4-styrenesulfonic acid) (PSSA) and polyvinyl alcohol (PVA) blend matrix have been developed using colloidal processing technique. The properties and the structure of prepared composites were investigated using Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), UV–vis spectroscopy (UV), Thermogravimetric analysis (TGA), Polarized optical microscopy (POM), Scanning electron microscopy (SEM) and Atomic force microscopy (AFM). The FTIR and Raman spectroscopy analysis indicate the strong interfacial interaction between GO and PSSA/PVA blend matrix. The XRD and SEM analysis confirm that GO was fully exfoliated into individual graphene sheets and dispersed homogeneously within the polymer matrix. The effective reinforcement of GO into PSSA/PVA blend matrix has resulted in the enhancement of dielectric constant. The dielectric constant has increased from 82.67 (50 Hz, 150 °C) for PSSA/PVA (50/50) blend to 297.91 (50 Hz, 150 °C) for PSSA/PVA/GO composites with 3 wt % GO loading. The dielectric loss (tan δ) has increased from 1.56 (50 KHz, 140 °C) for PSSA/PVA (50/50) blend to 2.64 (50 KHz, 140 °C) for PSSA/PVA/GO composites with 3 wt % GO loading. These findings provide a new insight to fabricate flexible, high-k dielectric composite as a promising material for energy storage applications. - Highlights: • Graphene Oxide was prepared from natural graphite using modified Hummers method. • Novel PSSA/PVA/GO composites were prepared by reinforcing GO into PSSA/PVA blend matrix. • Molecular level dispersion of GO in PSSA/PVA blend matrix was successfully achieved. • Enhancement in the dielectric constant was observed due to effective reinforcement of GO in PSSA/PVA blend matrix. • PSSA/PVA/GO composites with high dielectric performances can be considered for energy storage applications.

Molecularly imprinted poly (methacrylamide-co-methacrylic acid) composite membranes for recognition of curcumin

International Nuclear Information System (INIS)

Wang Ping; Hu Wenming; Su Weike

2008-01-01

In this study, molecularly imprinted poly (methacrylamide-co-methacrylic acid) composite membranes with different ratio of methacrylamide (MAM) versus methacrylic acid (MAA) were prepared via UV initiated photo-copolymerization on the commercial filter paper. Curcumin was chosen as the template molecule. Infra-red (IR) spectroscopy was used to study the binding mechanism between the imprinted sites and the templates. The morphology of the resultant membranes was visualized by scanning electron microscopy (SEM). Static equilibrium binding and recognition properties of the imprinted composite membranes to curcumin (cur-I) and its analogues demethoxycurcumin (cur-II) or bisdemethoxycurcumin (cur-III) were tested. The results showed that curcumin-imprinted membranes had the best recognition ability to curcumin compared to its analogues. From the results, the biggest selectivity factor of α cur-I/cur-II and α cur-I/cur-III were 1.50 and 5.94, and they were obtained from the composite membranes in which MAM/MAA were 1:4 and 0:1, respectively. The results of this study implied that the molecularly imprinted composite membranes could be used as separation membranes for curcumin enrichment

Surface roughness of composite resins subjected to hydrochloric acid.

Science.gov (United States)

Roque, Ana Carolina Cabral; Bohner, Lauren Oliveira Lima; de Godoi, Ana Paula Terossi; Colucci, Vivian; Corona, Silmara Aparecida Milori; Catirse, Alma Blásida Concepción Elizaur Benitez

2015-01-01

The purpose of this study was to determine the influence of hydrochloric acid on surface roughness of composite resins subjected to brushing. Sixty samples measuring 2 mm thick x 6 mm diameter were prepared and used as experimental units. The study presented a 3x2 factorial design, in which the factors were composite resin (n=20), at 3 levels: microhybrid composite (Z100), nanofilled composite (FiltekTM Supreme), nanohybrid composite (Ice), and acid challenge (n=10) at 2 levels: absence and presence. Acid challenge was performed by immersion of specimens in hydrochloric acid (pH 1.2) for 1 min, 4 times per day for 7 days. The specimens not subjected to acid challenge were stored in 15 mL of artificial saliva at 37 oC. Afterwards, all specimens were submitted to abrasive challenge by a brushing cycle performed with a 200 g weight at a speed of 356 rpm, totaling 17.8 cycles. Surface roughness measurements (Ra) were performed and analyzed by ANOVA and Tukey test (p≤0.05). Surface roughness values were higher in the presence (1.07±0.24) as compared with the absence of hydrochloric acid (0.72±0.04). Surface roughness values were higher for microhybrid (1.01±0.27) compared with nanofilled (0.68 ±0.09) and nanohybrid (0.48±0.15) composites when the specimens were not subjects to acid challenge. In the presence of hydrochloric acid, microhybrid (1.26±0.28) and nanofilled (1.18±0,30) composites presents higher surface roughness values compared with nanohybrid (0.77±0.15). The hydrochloric acid affected the surface roughness of composite resin subjected to brushing.

Crosslinking of thermoplastic composites using electron beam radiation

International Nuclear Information System (INIS)

Strong, A.B.; Black, S.R.; Bryce, G.R.; Olcott, D.D.

1991-01-01

The crosslinking of thermoset materials has been clearly demonstrated to improve many desirable physical and chemical properties for composite applications. While thermoplastic resins also offer many advantages for composite applications, they are not crosslinked and, therefore, may not meet the same property criteria as crosslinked thermosets. Electron beams have been used successfully for crosslinking non-reinforced thermoplastic materials. Electron beams have also been used for curing composite thermoset materials. This research utilizes electron beams to crosslink high performance thermoplastic composite materials (PEEK and PPS with glass and carbon fibers). The tensile strength and tensile modulus are compared under various crosslinking conditions. The method is found to have some advantages in potentially improving physical properties of thermoplastic composite materials

Composite Biofilms grown in Acidic Mining Lakes and assessed by Electron Microscopy and Molecular Techniques

International Nuclear Information System (INIS)

Luensdorf, Heinrich; Wenderoth, Dirk F.; Abraham, Wolf-Rainer

2002-01-01

Microbial consortia of composite biofilms, grown in surface water of acidicmining lakes near Lauchhammer, Germany, were investigated. The red-brown colored lake water was acidic (pH 2.5), had high concentrations of Fe(III), Al(III), and sulphate and low concentrations of dissolved organic matter. As a result the abundance of bacteria in the lake is with 10 4 cells mL -1 rather low. One input of organic material into the lake are autumnal leaves from trees, growing in the lakeside area. From aliquots of unfixed birch leave biofilms the 16S rRNA genes were amplified by PCR and community fingerprints were determined by single-strand conformation polymorphism (SSCP) analysis. Specific bands within the fingerprints were extracted from SSCP gels and sequenced for the taxonomical affiliation.These results were compared with those from the second type of biofilms which were grown on sterile substrata, floating submersed in surface waters of the lakes. By excising the bands from the gel and sequencing the individual bands bacterial taxa, common to both types of biofilms, were found but also some, which were only present in one type of biofilm. Ultrathin sectioned biofilms often showed bacteria associated with electron dense particles as main inorganic constituents. Elemental microanalysis by energy dispersive X-ray analysis (EDX) revealed them to contain iron, sulfur and oxygen as main elemental fractions and electron diffraction ring pattern analysis classified them to be schwertmannite. These bacteria and their interactions with each other as well as with the inorganic minerals formed in this lake generally is of great interest, in order to use these results for bioremediation applications

Plasticized Biodegradable Poly(lactic acid Based Composites Containing Cellulose in Micro- and Nanosize

Directory of Open Access Journals (Sweden)

Katalin Halász

2013-01-01

Full Text Available The aim of this work was to study the characteristics of thermal processed poly(lactic acid composites. Poly(ethylene glycol (PEG400, microcrystalline cellulose (MCC, and ultrasound-treated microcrystalline cellulose (USMCC were used in 1, 3, and 5 weight percents to modify the attributes of PLA matrix. The composite films were produced by twin screw extrusion followed by film extrusion. The manufactured PLA-based films were characterized by tensile testing, differential scanning calorimetry (DSC, scanning electron microscopy (SEM, wide angle X-ray diffraction (WAXD, and degradation test.

Electrochemical supercapacitor electrode material based on polyacrylic acid/polypyrrole/silver composite

International Nuclear Information System (INIS)

Patil, Dipali S.; Pawar, Sachin A.; Devan, Rupesh S.; Gang, Myeng Gil; Ma, Yuon-Ron; Kim, Jin Hyeok; Patil, Pramod S.

2013-01-01

Highlights: • Polyacrylic acid/polypyrrole/silver composite prepared by chemical polymerization method. • The presence of Ag nanoparticles on PPY spherical granules provides the least resistance path to electron. • The specific capacitance about 145 F g −1 and 226 F g −1 observed for PPY/PAA and PPY/PAA/Ag samples, respectively. • The higher specific energy 7.18 Wh kg −1 and 17.45 Wh kg −1 observed for PPY/PAA and PPY/PAA/Ag respectively at current density of 0.5 mA cm −2 . -- Abstract: In the present work, we have synthesized polypyrrole (PPY)/polyacrylic acid (PAA)/silver (Ag) composite electrodes by chemical polymerization via a simple and cost effective dip coating technique for supercapacitor application. Fourier transform-infrared, Fourier transform-Raman, X-ray photoelectron and energy dispersive X-ray spectroscopy techniques are used for the phase identification. Surface morphology of the films is examined by field emission scanning electron microscopy, which revealed granular structure for PPY, spherical interlaced granules for PPY/PAA and granules with bright spots of Ag nanoparticles for the PPY/PAA/Ag composites. The supercapacitive behavior of the electrodes is tested in three electrode system with 0.1 M H 2 SO 4 electrolyte by using cyclic voltammetery and charge discharge test. The highest specific capacitance 226 F g −1 at 10 mV s −1 and energy density of 17.45 Wh kg −1 at 0.5 mA cm −2 is obtained for the PPY/PAA/Ag composite electrodes. Present work demonstrates an easy way of improving specific capacitance of the polymer electrodes. Thus the work will open a new avenue for designing low cost high performance devices for better supercapacitors

Advanced composite materials based on polyhydroxybutyrate and polylactic acid

Science.gov (United States)

Tubaeva, P. M.; Olkhov, A. A.; Podzorova, M. V.; Popov, A. A.

2017-12-01

In this paper, we consider the main characteristics of polyhydroxybutyrate (PHB) and polylactic acid (PLA) as well as the prospects and possibility of the medical use of PHB-PLA compositions as these polymers are most relevant to such application. The study establishes the main thermophysical parameters of PHB and PLA. It is found that PHB and PLA are hydrophobic enough. The study by the electron paramagnetic resonance method reveals a small amount of the radical infiltrated in PLA and PHB, which indicates the chain rigidity of both polymeric structures. Mechanical properties of PLA and PHB are characterized by high strength and low elasticity.

Synthesis and electrochemical analysis of polyaniline/TiO2 composites prepared with various molar ratios between aniline monomer and para-toluenesulfonic acid

International Nuclear Information System (INIS)

Oh, Misoon; Kim, Seok

2012-01-01

Graphical abstract: Polyaniline (PANI)/TiO 2 composites were prepared by in situ polymerization using para-toluenesulfonic acid (p-TSA). The composites showed different morphology and specific capacitances as a function of aniline concentration, which are related to the morphology (shape or size) of particles. Scheme of the formation of composites consisting of PANI film and the micelle structures is shown. Highlights: ► PANI/TiO 2 composite were prepared with a different concentration of monomer and dopant. ► Aniline/acid ratio influenced the morphological and electrochemical properties. ► The composites showed different capacitances as a function of aniline concentrations. ► Aniline/acid ratio could influence on the dispersion and surface roughness of particles. - Abstract: Polyaniline (PANI)/titanium dioxide (TiO 2 ) composites were prepared with a chemical oxidation polymerization of aniline monomer (ANI) with various molar ratios between ANI and para toluenesulfonic acid (p-TSA). To find an effect of the [ANI]:[p-TSA] molar ratio on the electrochemical properties of the prepared PANI/TiO 2 composites, the composites were synthesized under same conditions except the p-TSA concentrations. The prepared composite films had more homogeneous TiO 2 dispersion with changing [ANI]:[p-TSA] molar ratios from 6:1 to 1:1. p-TSA surfactant-like doping acid helped the dispersion of TiO 2 particles in the PANI matrix. PANI covering the TiO 2 surfaces was confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Prepared PANI films on the TiO 2 particles had the smoothest surface when the ANI and p-TSA had 1:1 molar ratio in the reaction solution. The composite prepared with molar ratio [ANI]:[p-TSA] of 3:1 had the highest capacitance (800 F g −1 ) among the prepared composites.

Fatty acid composition of Swedish bakery products, with emphasis on trans-fatty acids.

Science.gov (United States)

Trattner, Sofia; Becker, Wulf; Wretling, Sören; Öhrvik, Veronica; Mattisson, Irene

2015-05-15

Trans-fatty acids (TFA) have been associated with increased risk of coronary heart disease, by affecting blood lipids and inflammation factors. Current nutrition recommendations emphasise a limitation of dietary TFA intake. The aim of this study was to investigate fatty acid composition in sweet bakery products, with emphasis on TFA, on the Swedish market and compare fatty acid composition over time. Products were sampled in 2001, 2006 and 2007 and analysed for fatty acid composition by using GC. Mean TFA levels were 0.7% in 2007 and 5.9% in 2001 of total fatty acids. In 1995-97, mean TFA level was 14.3%. In 2007, 3 of 41 products had TFA levels above 2% of total fatty acids. TFA content had decreased in this product category, while the proportion of saturated (SFA) and polyunsaturated (PUFA) fatty acids had increased, mostly through increased levels of 16:0 and 18:2 n-6, respectively. The total fat content remained largely unchanged. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Novel composite material polyoxovanadate@MIL-101(Cr): a highly efficient electrocatalyst for ascorbic acid oxidation.

Science.gov (United States)

Fernandes, Diana M; Barbosa, André D S; Pires, João; Balula, Salete S; Cunha-Silva, Luís; Freire, Cristina

2013-12-26

A novel hybrid composite material, PMo10V2@MIL-101 was prepared by the encapsulation of the tetra-butylammonium (TBA) salt of the vanadium-substituted phosphomolybdate [PMo10V2O40](5-) (PMo10V2) into the porous metal-organic framework (MOF) MIL-101(Cr). The materials characterization by powder X-ray diffraction, Fourier transform infrared spectra and scanning electron microscopy confirmed the preparation of the composite material without disruption of the MOF porous structure. Pyrolytic graphite electrodes modified with the original components (MIL-101(Cr), PMo10V2), and the composite material PMo10V2@MIL-101 were prepared and their electrochemical responses were studied by cyclic voltammetry. Surface confined redox processes were observed for all the immobilized materials. MIL-101(Cr) showed one-electron reduction process due to chromium centers (Cr(III) → Cr(II)), while PMo10V2 presented five reduction processes: the peak at more positive potentials is attributed to two superimposed 1-electron vanadium reduction processes (V(V) → V(IV)) and the other four peaks to Mo-centred two-electron reduction processes (Mo(VI) → Mo(V)). The electrochemical behavior of the composite material PMo10V2@MIL-101 showed both MIL-101(Cr) and PMo10V2 redox features, although with the splitting of the two vanadium processes and the shift of the Mo- and Cr- centered processes to more negative potentials. Finally, PMo10V2@MIL-101 modified electrode showed outstanding enhanced vanadium-based electrocatalytic properties towards ascorbic acid oxidation, in comparison with the free PMo10V2, as a result of its immobilization into the porous structure of the MOF. Furthermore, PMo10V2@MIL-101 modified electrode showed successful simultaneous detection of ascorbic acid and dopamine.

Single step synthesis of gold-amino acid composite, with the evidence of the catalytic hydrogen atom transfer (HAT) reaction, for the electrochemical recognition of Serotonin

Science.gov (United States)

Choudhary, Meenakshi; Siwal, Samarjeet; Nandi, Debkumar; Mallick, Kaushik

2016-03-01

A composite architecture of amino acid and gold nanoparticles has been synthesized using a generic route of 'in-situ polymerization and composite formation (IPCF)' [1,2]. The formation mechanism of the composite has been supported by a model hydrogen atom (H•≡H++e-) transfer (HAT) type of reaction which belongs to the proton coupled electron transfer (PCET) mechanism. The 'gold-amino acid composite' was used as a catalyst for the electrochemical recognition of Serotonin.

Ammonia Gas Sensing Behavior of Tanninsulfonic Acid Doped Polyaniline-TiO2 Composite

Directory of Open Access Journals (Sweden)

Venu Gopal Bairi

2015-10-01

Full Text Available A highly active tannin doped polyaniline-TiO2 composite ammonia gas sensor was developed and the mechanism behind the gas sensing activity was reported for the first time. A tanninsulfonic acid doped polyaniline (TANIPANI-titanium dioxide nanocomposite was synthesized by an in situ polymerization of aniline in the presence of tanninsulfonic acid and titanium dioxide nanoparticles. X-ray diffraction and thermogravimetric analysis were utilized to determine the incorporation of TiO2 in TANIPANI matrix. UV-Visible and infrared spectroscopy studies provided information about the electronic interactions among tannin, polyaniline, and TiO2. Scanning electron microscopy (SEM along with energy dispersive X-ray spectroscopy (EDS and atomic force microscopy (AFM surface analysis techniques were used to investigate the metal oxide dispersions inside polyaniline matrix. Gas sensors were prepared by spin coating solutions of TANIPANI-TiO2 and TANIPANI composites onto glass slides. Sensors were tested at three different concentrations (20 ppm, 40 ppm, and 60 ppm of ammonia gas at ambient temperature conditions by measuring the changes in surface resistivity of the films with respect to time. Ammonia gas sensing plots are presented showing the response values, response times and recovery times. The TANIPANI-TiO2 composite exhibited better response and shorter recovery times when compared to TANIPANI control and other polyaniline composites that have been reported in the literature. For the first time a proposed mechanism of gas sensing basing on the polaron band localization and its effects on the gas sensing behavior of polyaniline are reported.

Preparation and properties of highly conductive palmitic acid/graphene oxide composites as thermal energy storage materials

International Nuclear Information System (INIS)

Mehrali, Mohammad; Latibari, Sara Tahan; Mehrali, Mehdi; Indra Mahlia, Teuku Meurah; Cornelis Metselaar, Hendrik Simon

2013-01-01

PA/GO (palmitic acid/graphene oxide) as PCMs (phase change materials) prepared by vacuum impregnation method, have high thermal conductivity. The GO (graphene oxide) composite was used as supporting material to improve thermal conductivity and shape stabilization of composite PCM (phase change material). SEM (Scanning electronic microscope), FT-IR (Fourier transformation infrared spectroscope) and XRD (X-ray diffractometer) were applied to determine microstructure, chemical structure and crystalloid phase of palmitic acid/GO composites, respectively. DSC (Differential scanning calorimeter) test was done to investigate thermal properties which include melting and solidifying temperatures and latent heat. FT-IR analysis represented that the composite instruction of porous palmitic acid and GO were physical. The temperatures of melting, freezing and latent heats of the composite measured through DSC analysis were 60.45, 60.05 °C, 101.23 and 101.49 kJ/kg, respectively. Thermal cycling test showed that the form-stable composite PCM has good thermal reliability and chemical stability. Thermal conductivity of the composite PCM was improved by more than three times from 0.21 to 1.02. As a result, due to their acceptable thermal properties, good thermal reliability, chemical stability and great thermal conductivities, we can consider the prepared form-stable composites as highly conductive PCMs for thermal energy storage applications. - Highlights: • Novel composite PCM with high thermal conductivity and latent heat storage. • New thermal cycling test for thermal reliability of composite PCMs. • Increasing thermal conductivity of composite PCM with graphene oxide. • Increasing thermal stability of phase change material by adding graphene oxide

Process for hardening an alkyd resin composition using ionizing radiation. [electron beams, gamma radiation

Energy Technology Data Exchange (ETDEWEB)

Watanabe, T; Murata, K; Maruyama, T

1969-11-27

In an alkyd resin composition having free hydroxide radicals and containing a conjugated unsaturated fatty acid and/or oil as a component thereof, a process for hardening an alkyd resin composition comprises the steps of dissolving into a vinyl monomer, the product obtained by the semi-esterification reaction of said hydroxide radicals with acid anhydrides having polymerizable radicals and hardening by ionizing radiation to provide a coating with a high degree of cross-linking, with favorable properties such as toughness, hardness, chemical resistance and resistance to weather and with the feasibility of being applied as the ground and finish coat on metals, wood, paper, outdoor construction or the like. Any kind of ionization radiation, particularly accelerated electron beams, ..gamma.. radiation can be used at 50/sup 0/C to -5/sup 0/C for a few seconds or minutes, permitting continuous operation. In one example, 384 parts of phthalic anhydride, 115 parts of pentaerythritol, 233 parts of trimethylol ethane, 288 parts of tung fatty acid and 49 parts of para-tertiary-butyl benzoic acid are mixed and heated with 60 parts of xylene to an acid value of 12. In addition, 271 parts of maleic anhydride and 0.6 parts of hydroquinone are admixed with the content and heated to terminate the reaction. 100 parts of a 50% stylene solution of this alkyd resin are mixed with 1 part of a 60% toluene solution of cobalt naphthenate, and then coated on a glass plate and irradiated with high energy electron beams of 300 kV with a dose of 5 Mrad for 1 sec.

Chemical mechanical polishing of hard disk substrate with {alpha}-alumina-g-polystyrene sulfonic acid composite abrasive

Energy Technology Data Exchange (ETDEWEB)

Lei Hong, E-mail: hong_lei2005@yahoo.com.c [Research Center of Nano-science and Nano-technology, Shanghai University, Shanghai 200444 (China); Bu Naijing; Chen Ruling; Hao Ping [Research Center of Nano-science and Nano-technology, Shanghai University, Shanghai 200444 (China); Neng Sima; Tu Xifu; Yuen Kwok [Shenzhen Kaifa Magnetic Recording Co., LTD, Shenzhen, 518035 (China)

2010-05-03

{alpha}-Alumina-g-polystyrene sulfonic acid ({alpha}-Al{sub 2}O{sub 3}-g-PSS) composite abrasive was prepared by surface activation, graft polymerization and sulfonation, successively. The composition, dispersibility and morphology of the product were characterized by Fourier transformed infrared spectroscopy, laser particle size analysis and scanning electron microscopy, respectively. The chemical mechanical polishing (CMP) performances of the composite abrasive on hard disk substrate with nickel-phosphorous plating were investigated. The microscopy images of the polished surfaces show that {alpha}-Al{sub 2}O{sub 3}-g-PSS composite abrasive results in improved CMP and post-CMP cleaning performances than pure {alpha}-alumina abrasive under the same testing conditions.

Eicosapentaenoic Acid Supplementation Changes Fatty Acid Composition and Corrects Endothelial Dysfunction in Hyperlipidemic Patients

Directory of Open Access Journals (Sweden)

Ken Yamakawa

2012-01-01

Full Text Available We investigated the effects of purified eicosapentaenoic acid (EPA on vascular endothelial function and free fatty acid composition in Japanese hyperlipidemic subjects. In subjects with hyperlipidemia (total cholesterol ≥220 mg/dL and/or triglycerides ≥150 mg/dL, lipid profile and forearm blood flow (FBF during reactive hyperemia were determined before and 3 months after supplementation with 1800 mg/day EPA. Peak FBF during reactive hyperemia was lower in the hyperlipidemic group than the normolipidemic group. EPA supplementation did not change serum levels of total, HDL, or LDL cholesterol, apolipoproteins, remnant-like particle (RLP cholesterol, RLP triglycerides, or malondialdehyde-modified LDL cholesterol. EPA supplementation did not change total free fatty acid levels in serum, but changed the fatty acid composition, with increased EPA and decreased linoleic acid, γ-linolenic acid, and dihomo-γ-linolenic acid. EPA supplementation recovered peak FBF after 3 months. Peak FBF recovery was correlated positively with EPA and EPA/arachidonic acid levels and correlated inversely with dihomo-γ-linolenic acid. EPA supplementation restores endothelium-dependent vasodilatation in hyperlipidemic patients despite having no effect on serum cholesterol and triglyceride patterns. These results suggest that EPA supplementation may improve vascular function at least partly via changes in fatty acid composition.

Profiling Abscisic Acid-Induced Changes in Fatty Acid Composition in Mosses.

Science.gov (United States)

Shinde, Suhas; Devaiah, Shivakumar; Kilaru, Aruna

2017-01-01

In plants, change in lipid composition is a common response to various abiotic stresses. Lipid constituents of bryophytes are of particular interest as they differ from that of flowering plants. Unlike higher plants, mosses have high content of very long-chain polyunsaturated fatty acids. Such lipids are considered to be important for survival of nonvascular plants. Here, using abscisic acid (ABA )-induced changes in lipid composition in Physcomitrella patens as an example, a protocol for total lipid extraction and quantification by gas chromatography (GC) coupled with flame ionization detector (FID) is described.

Preparation and characterization of rubbery epoxy/multiwall carbon nanotubes composites using amino acid salt assisted dispersion technique

Directory of Open Access Journals (Sweden)

S. B. Jagtap

2013-04-01

Full Text Available Epoxy/multiwall carbon nanotubes (MWCNT composites were prepared using sodium salt of 6-aminohexanoic acid (SAHA modified MWCNT and its effect properties of related composites were investigated. The composite prepared using a polar solvent, tetrahydrofuran exhibits better mechanical properties compared to those prepared using less polar solvent and without using solvent. The tensile properties and dynamic storage modulus was found to be increased as a result of modification of MWCNT with SAHA. This improvement in the tensile properties and dynamic mechanical properties of epoxy/MWCNT composite is a combined effect of cation-π interaction and chemical bonding. Fourier transform infrared spectroscopy (FTIR and Raman spectroscopy were used to explain cation-π interaction between SAHA with MWCNT and chemical bonding of SAHA with epoxy resin. The effect of modification of MWCNT on morphology of a nanocomposite was confirmed by using scanning electron microscopy (SEM and transmission electron microscopy (TEM. The present approach does not disturb the ! electron clouds of MWCNT as opposed to chemical functionalization strategy.

Effect of altitude on fatty acid composition in Turkish hazelnut ...

African Journals Online (AJOL)

The objective of this study was to evaluate the change of fatty acid composition in Delisava, Yomra, Sivri and Karayaglı Turkish hazelnut varieties with altitude. Fatty acid composition were determined by gas chromatography (GC) equiped with flame ionisation detector (FID) after obtained fatty acid methyl esters from crude ...

Electron-induced chemistry in microhydrated sulfuric acid clusters

Science.gov (United States)

Lengyel, Jozef; Pysanenko, Andriy; Fárník, Michal

2017-11-01

We investigate the mixed sulfuric acid-water clusters in a molecular beam experiment with electron attachment and negative ion mass spectrometry and complement the experiment by density functional theory (DFT) calculations. The microhydration of (H2SO4)m(H2O)n clusters is controlled by the expansion conditions, and the electron attachment yields the main cluster ion series (H2SO4)m(H2O)nHSO4- and (H2O)nH2SO4-. The mass spectra provide an experimental evidence for the onset of the ionic dissociation of sulfuric acid and ion-pair (HSO4- ṡ ṡ ṡ H3O+) formation in the neutral H2SO4(H2O)n clusters with n ≥ 5 water molecules, in excellent agreement with the theoretical predictions. In the clusters with two sulfuric acid molecules (H2SO4)2(H2O)n this process starts as early as n ≥ 2 water molecules. The (H2SO4)m(H2O)nHSO4- clusters are formed after the dissociative electron attachment to the clusters containing the (HSO4- ṡ ṡ ṡ H3O+) ion-pair structure, which leads to the electron recombination with the H3O+ moiety generating H2O molecule and the H-atom dissociation from the cluster. The (H2O)nH2SO4- cluster ions point to an efficient caging of the H atom by the surrounding water molecules. The electron-energy dependencies exhibit an efficient electron attachment at low electron energies below 3 eV, and no resonances above this energy, for all the measured mass peaks. This shows that in the atmospheric chemistry only the low-energy electrons can be efficiently captured by the sulfuric acid-water clusters and converted into the negative ions. Possible atmospheric consequences of the acidic dissociation in the clusters and the electron attachment to the sulfuric acid-water aerosols are discussed.

Perfluoroalkyl acid contamination and polyunsaturated fatty acid composition of French freshwater and marine fishes.

Science.gov (United States)

Yamada, Ami; Bemrah, Nawel; Veyrand, Bruno; Pollono, Charles; Merlo, Mathilde; Desvignes, Virginie; Sirot, Véronique; Oseredczuk, Marine; Marchand, Philippe; Cariou, Ronan; Antignac, Jean-Phillippe; Le Bizec, Bruno; Leblanc, Jean-Charles

2014-07-30

In this study, French marine and freshwater fish perfluoroalkyl acid (PFAA) contamination are presented along with their fatty acid (FA) composition to provide further elements for a risk/benefit balance of fish consumption to be assessed. The 29 most consumed marine fish species were collected in four metropolitan French coastal areas in 2004 to constitute composite samples. Geographical differences in terms of consumed species and contamination level were taken into account. Three hundred and eighty-seven composite samples corresponding to 16 freshwater fish species collected between 2008 and 2010 in the six major French rivers or their tributaries were selected among the French national agency for water and aquatic environments freshwater fish sample library. The raw edible parts were analyzed for FA composition and PFAA contamination. Results show that freshwater fishes are more contaminated by PFAAs than marine fishes and do not share the same contamination profile. Freshwater fish contamination is mostly driven by perfluorooctane sulfonate (PFOS) (75%), whereas marine fish contamination is split between perfluorooctanoic acid (PFOA) (24%), PFOS (20%), perfluorohexanoic acid (PFHxA) (15%), perfluoropentanoic acid (PFHpA) (11%), and perfluorobutanoic acid (PFBA) (11%). Common carp, pike-perch, European perch, thicklip grey mullet, and common roach presented the most unfavorable balance profile due to their high level of PFAAs and low level of n-3 long-chain polyunsaturated fatty acids (LC-PUFAs). These data could be used, if needed, in an updated opinion on fish consumption that takes into account PFAA contamination.

Composition, texture and methane potential of cellulosic residues from Lewis acids organosolv pulping of wheat straw.

Science.gov (United States)

Constant, Sandra; Barakat, Abdellatif; Robitzer, Mike; Di Renzo, Francesco; Dumas, Claire; Quignard, Françoise

2016-09-01

Cellulosic pulps have been successfully isolated from wheat straw through a Lewis acids organosolv treatment. The use of Lewis acids with different hardness produced pulps with different delignification degrees. The cellulosic residue was characterised by chemical composition, X-ray diffraction, FT-IR spectroscopy, N2 physisorption, scanning electron microscopy and potential for anaerobic digestibility. Surface area and pore volume increased with the hardness of the Lewis acid, in correspondence with the decrease of the amount of lignin and hemicellulose in the pulp. The non linearity of the correlation between porosity and composition suggests that an agglomeration of cellulose fibrils occurs in the early stages of pulping. All organosolv pulps presented a significantly higher methane potential than the parent straw. A methane evolution of 295Ncm(3)/g OM was reached by a moderate improvement of the accessibility of the native straw. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fatty acid composition of forage herb species

DEFF Research Database (Denmark)

Warner, D.; Jensen, Søren Krogh; Cone, J.W.

2010-01-01

The use of alternative forage species in grasslands for intensive livestock production is receiving renewed attention. Data on fatty acid composition of herbs are scarce, so four herbs (Plantago lanceolata, Achillea millefolium, Cichorium intybus, Pastinaca sativa) and one grass species (timothy......, Phleum pratense) were sown in a cutting trial. The chemical composition and concentration of fatty acids (FA) of individual species were determined during the growing season. Concentrations of crude protein and FA were generally higher in the herbs than in timothy. C. intybus had the highest nutritive...

Is the fatty acid composition of Daphnia galeata determined by the fatty acid composition of the ingested diet?

NARCIS (Netherlands)

Weers, P.M.M.; Siewertsen, K.; Gulati, R.D.

1997-01-01

1. The fatty acid (FA) composition of Daphnia galeata and their algal food was analysed and showed many similarities, however, some significant differences were also found in the relative abundance of the FA C16:4 omega 3 and docosahexaenoic acid (DHA). Their relative abundances were much lower in

Study on thermal property of lauric–palmitic–stearic acid/vermiculite composite as form-stable phase change material for energy storage

Directory of Open Access Journals (Sweden)

Nan Zhang

2015-09-01

Full Text Available The form-stable composite phase change material of lauric–palmitic–stearic acid ternary eutectic mixture/vermiculite was prepared by vacuum impregnation method for thermal energy storage. The maximum mass fraction of lauric–palmitic–stearic acid ternary eutectic mixture retained in vermiculite was determined as 50 wt% without melted phase change material seepage from the composite phase change material. Fourier transformation infrared spectroscope and scanning electron microscope were used to characterize the structure and morphology of the prepared lauric–palmitic–stearic acid ternary eutectic mixture/vermiculite form-stable composite phase change material, and the results indicate that lauric–palmitic–stearic acid ternary eutectic mixture was well confined into the layer porous structure of vermiculite by physical reaction. The melting and freezing temperatures and latent heats were measured by differential scanning calorimeter as 31.4°C and 30.3°C, and 75.8 and 73.2 J/g, respectively. Thermal cycling test showed that there was no significant change in the thermal properties of lauric–palmitic–stearic acid ternary eutectic mixture/vermiculite form-stable composite phase change material after 1000 thermal cycles. Moreover, 2 wt% expanded graphite was added to improve the thermal conductivity of lauric–palmitic–stearic acid ternary eutectic mixture/vermiculite form-stable composite phase change material. All results indicated that the prepared lauric–palmitic–stearic acid ternary eutectic mixture/vermiculite form-stable composite phase change material had suitable thermal properties and good thermal reliability for the application of thermal energy storage in building energy efficiency.

Electron field emission from screen-printed graphene/DWCNT composite films

International Nuclear Information System (INIS)

Xu, Jinzhuo; Pan, Rong; Chen, Yiwei; Piao, Xianqin; Qian, Min; Feng, Tao; Sun, Zhuo

2013-01-01

Highlights: ► The field emission performance improved significantly when adding graphene into DWCNTs as the emission material. ► We set up a model of pure DWCNT films and graphene/DWCNT composite films. ► We discussed the contact barrier between emission films and electric substrates by considering the Fermi energies of silver, DWCNT and graphene. - Abstract: The electron field emission properties of graphene/double-walled carbon nanotube (DWCNT) composite films prepared by screen printing have been systematically studied. Comparing with the pure DWCNT films and pure graphene films, a significant enhancement of electron emission performance of the composite films are observed, such as lower turn-on field, higher emission current density, higher field enhancement factor, and long-term stability. The optimized composite films with 20% weight ratio of graphene show the best electron emission performance with a low turn-on field of 0.62 V μm −1 (at 1 μA cm −2 ) and a high field enhancement factor β of 13,000. A model of the graphene/DWCNT composite films is proposed, which indicate that a certain amount of graphene will contribute the electron transmission in the silver substrate/composite films interface and in the interior of composite films, and finally improve the electron emission performance of the graphene/DWCNT composite films.

Study of morphology and mechanical properties of hydrophilic films based on compositions of poly(acrylic acid) and poly(2-hydroxy ethylvinylether)

International Nuclear Information System (INIS)

Bitekenova, A.; Dzhusupbekova, A.; Khutoryanskij, V.; Nurkeeva, Z.

2003-01-01

The hydrophilic films based on compositions of poly(acrylic acid) and poly(2-hydroxy ethylvinylether) were obtained from blend of the corresponding monomers. Radiation crosslinking of composite materials are realize by γ-irradiation method and the gelation doses were calculated. It was shown that mechanical properties of films depend on composition (content of notion component) and conditions of crosslinking. The morphology of polymeric films was investigated by scanning electron microscopy

Radiation-curable coating composition

International Nuclear Information System (INIS)

Mibae, Jiro; Kawamura, Hiroshi; Takahashi, Masao.

1970-01-01

A radiation-curable coating composition, suitable for metal precoating, is provided. The composition is prepared by mixing 50 to 90 parts of a long chain fatty acid ester (A) with 10 to 50 parts of monomer (B) which is copolymerizable with (A). (A) is prepared by reacting a dimer acid (particularly the dimer of linolenic acid) with hydroxyalkyl methacrylate or glycidyl methacrylate. Upon irradiation with electron beams (0.1 to 3 MeV) the composition cures to yield a coating of high adhesion, impact resistance and bending resistance. In one example, 100 g of dimer acid (Versadime 216, manufactured by General Mills) was esterified with 50 g of 2-hydroxyethyl methacrylate. A zinc plated iron plate was coated with the product and irradiated with electron beams (2 Mrad). Pencil hardness was F; adhesion 0: impact resistance (Du Pont) 1 kg x 30 cm; bending resistance 2T. (Kaichi, S.)

Synthesis of water dispersible polyaniline/poly(styrenesulfonic acid) modified graphene composite and its electrochemical properties

International Nuclear Information System (INIS)

Luo, Jing; Jiang, Sisi; Liu, Ren; Zhang, Yongjie; Liu, Xiaoya

2013-01-01

A novel water-dispersible polyaniline (PANI)/graphene composite was prepared by the in situ polymerization of aniline on the surface of poly(styrenesulfonic acid) (PSS) coated graphene nanosheets (PSS-GR). The characterization of atomic force microscopy (AFM), transmission electron microscopy (TEM), Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy confirmed the successful synthesis of PANI/PSS-GR composites and strong interaction between PANI and PSS-GR. The as-synthesized PANI/PSS-GR composite is readily dispersible in water and forms a homogeneous aqueous dispersion which is stable for more than one month. More interestingly, PSS-GR can dope PANI effectively and shift its electroactivity to a neutral or even alkaline environment, making them promising candidates for biological application. In addition, the PANI/PSS-GR composite shows improved electrical conductivity and electrochemical stability compared to the neat polyaniline. Furthermore, the potential use of this composite for detection of ascorbic acid (AA) was investigated. A low detection limit of 5 × 10 −6 M and a linear detection range between 1 × 10 −4 M and 1 × 10 −3 M was attained, indicating the high electrocatalytic ability of this composite. Anticipatedly, the synthesized composite will find promising applications as a novel electrode material in sensors and other devices in virtue of their outstanding characteristics of water-dispersibility, good cycle stability, electroactivity in neutral solution and excellent electrocatalytic ability

Effects of high pressure processing on fatty acid composition and volatile compounds in Korean native black goat meat.

Science.gov (United States)

Kang, Geunho; Cho, Soohyun; Seong, Pilnam; Park, Beomyoung; Kim, Sangwoo; Kim, Donghun; Kim, Youngjun; Kang, Sunmun; Park, Kyoungmi

2013-08-01

This study investigated the effects of high pressure processing (HPP) on fatty acid composition and volatile compounds in Korean native black goat (KNBG) meat. Fatty acid content in KNBG meat was not significantly (p > 0.05) different among the control goats and those subjected HPP. The 9,12-octadecadienoic acid and octadecanoic acid, well-known causes of off-flavors, were detected from meat of some KNBG. A difference between the control and HPP treatment was observed in the discriminated function analysis using an electronic nose. The results suggest that the volatile compounds in KNBG meat were affected by HPP.

Fatty acid composition of human milk and infant formulas

Directory of Open Access Journals (Sweden)

Ivančica Delaš

2005-04-01

Full Text Available The appropriate fatty acid composition of membrane lipids is necessary for structure and function of the developing nervous system. Rapid synthesis of brain tissue occurs during the last trimester of pregnancy and the early postnatal weeks. This synthesis of brain structure involves the formation of complex lipids, many of which contain significant quantities of essential fatty acids and their higher homologs. This study was undertaken to elucidate how fatty acid compositions of available diets for infants meet the requirements for essential fatty acids. Samples of infant formulas, present on the market, as well as milk samples obtained from breast feeding mothers, were extracted by chloroform : methanol mixtures in order to obtain total lipids. Fatty acid methyl esters were prepared and fatty acid composition was revealed by gas chromatography. Special interest was directed to the content of long chain polyunsaturated fatty acids. The results have shown that infant formulas, designed to substitute mothers’ breast milk, contain medium chain fatty acids (C 10:0, C 12:0, along with the other saturated fatty acids, in the amounts acceptable for infants’ energy consumption. Although linoleic acid (C18:2, n-6 was present at the level expected to cover needs for essential fatty acids, most of the tested products did not contain sufficient amounts of long chain polyunsaturated fatty acids, despite the fact that these fatty acids are necessary for undisturbed brain development, ignoring the strong recommendations that they should be used as a supplement in infants’ food.

Effects of electron irradiation on LDPE/MWCNT composites

Energy Technology Data Exchange (ETDEWEB)

Yang, Jianqun [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Li, Xingji, E-mail: lxj0218@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Liu, Chaoming; Rui, Erming [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Wang, Liqin [School of Mechatronics, Harbin Institute of Technology, Harbin 150001 (China)

2015-12-15

In this study, mutiwalled carbon nanotubes (MWCNTs) were incorporated into low density polyethylene (LDPE) in different concentrations (2%, 4% and 8%) using a melt blending process. Structural, thermal stability and tensile property of the unirradiated/irradiated LDPE/MWCNT composites by 110 keV electrons were investigated by means of scanning electron microscopy (SEM), small angle X-ray scattering (SAXS), Raman spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, thermogravimetric analysis (TGA) and uniaxial tensile techniques. Experimental results show that the addition of MWCNTs obviously increases the ultimate tensile strength of LDPE and decreases the elongation at break, which is attributed to the homogeneous distribution of the MWCNTs in LDPE and intense interaction between MWCNTs and LDPE matrix. Also, the electron irradiation further increases the ultimate tensile strength of LDPE/MWCNT composites, which can be ascribed to the more intense interaction between MWCNTs and LDPE matrix, and the formation of crosslinking sites in LDPE matrix induced by the electron irradiation. The addition of MWCNTs significantly enhances thermal stability of the LDPE due to the hindering effect and the scavenging free radicals, while the electron irradiation decreases thermal stability of the LDPE/MWCNT composites since the structure of the MWCNTs and LDPE matrix damages.

p-toluene sulfonic acid doped polyaniline carbon nanotube composites: synthesis via different routes and modified properties

Directory of Open Access Journals (Sweden)

ASHOK K. SHARMA

2013-04-01

Full Text Available Composites of polyaniline and carbon nanotube (CNT were prepared by in-situ chemical polymerization method using various aniline concentrations in the initial polymerization solution with p-toluene sulfonic acid (PTS as secondary dopant and mechanical mixing of the PANI and CNT using different weight ratios of PANI and CNTs. The structural characterizations of the composites were done by Fourier transform infrared (FTIR and Ultra violet visible spectroscopy (UV-Visible. Scanning electron microscopy (SEM was used to characterize the surface morphology of the composites. It was found that the composites prepared by in-situ chemical polymerization had smoother surface morphology in comparison to the composites obtained by mechanical mixing. The capacitive studies reveal that the in-situ composite has synergistic effect and the specific capacitance of the composite calculated from cyclic voltammogram (CV was 385.1 F/g. Thermal studies indicate that the composites are stable as compared to PANI alone showing that the CNT contributes towards thermal stability in the PANI-CNT composites.

Estimation and analysis of the sensitivity of monoenergetic electron radiography of composite materials with fluctuating composition

International Nuclear Information System (INIS)

Rudenko, V.N.; Yunda, N.T.

1978-01-01

A sensitivity analysis of the electron defectoscopy method for composite materials with fluctuating composition has been carried out. Quantitative evaluations of the testing sensitivity depending on inspection conditions have been obtained, and calculations of the instrumental error are shown. Based on numerical calculations, a comparison of error has been carried out between high-energy electron and X-ray testings. It is shown that when testing composite materials with a surface density of up to 7-10 g/cm 2 , the advantage of the electron defectoscopy method as compared to the X-ray one is the higher sensitivity and lower instrumental error. The advantage of the electron defectoscopy method over the X-ray one as regards the sensitivity is greater when a light-atom component is predomenant in the composition. A monoenergetic electron beam from a betatron with an energy of up to 30 MeV should be used for testing materials with a surface density of up to 15 g/cm 2

Electron beam curing of composites in North America

International Nuclear Information System (INIS)

Berejka, Anthony J.; Eberle, Cliff

2002-01-01

Electron beam curing of fiber-reinforced composites was explored over 30 years ago. Since then there have been developments in accelerator technology, in processes for handling materials presented to an accelerator, and in materials that can be used as matrix binders. In recent years in North America, Cooperative Research and Development Agreements (CRADAs) have been formed involving collaboration amongst materials suppliers, accelerator manufacturers and service providers, national laboratories, such as Oak Ridge National Laboratory, and interested potential users. The scope and status of these CRADAs are reviewed along with other recent developments in the electron beam curing of composites in North America. Innovative and proprietary materials technology has been developed and progress made toward implementing commercial practice. Significant market interest has developed in the military/aerospace industries that are finding the process and performance of electron beam cured composites to offer significant benefits

Training affects muscle phospholipid fatty acid composition in humans

DEFF Research Database (Denmark)

Helge, Jørn Wulff; Wu, B J; Willer, Mette

2001-01-01

on the muscle membrane phospholipid fatty acid composition in humans. Seven male subjects performed endurance training of the knee extensors of one leg for 4 wk. The other leg served as a control. Before, after 4 days, and after 4 wk, muscle biopsies were obtained from the vastus lateralis. After 4 wk......, the phospholipid fatty acid contents of oleic acid 18:1(n-9) and docosahexaenoic acid 22:6(n-3) were significantly higher in the trained (10.9 +/- 0.5% and 3.2 +/- 0.4% of total fatty acids, respectively) than the untrained leg (8.8 +/- 0.5% and 2.6 +/- 0.4%, P fatty acids...... was significantly lower in the trained (11.1 +/- 0.9) than the untrained leg (13.1 +/- 1.2, P fatty acid composition. Citrate synthase activity was increased by 17% in the trained compared with the untrained leg (P

Structure and properties of compositions based on petroleum sulfonic acids

Energy Technology Data Exchange (ETDEWEB)

Tutorskii, I.A.; Sultanova, A.S.; Belkina, E.V.; Fomin, A.G. [Lomonosov Academy of Fine Chemical Technology, Moscow (Russian Federation)

1995-03-01

Colloidal characteristics of compositions based on petroleum sulfonic acids were studied. Neutralized heavy oil residue exhibits surface-active properties and contains an ultradisperse filler. Analysis of the compositions by size-exclusion-chromatography shows deep structural changes in the heavy acid residue upon neutralization with calcium carbonate.

Complete doping in solid-state by silica-supported perchloric acid as dopant solid acid: Synthesis and characterization of the novel chiral composite of poly [(±)-2-(sec-butyl) aniline

Energy Technology Data Exchange (ETDEWEB)

Farrokhzadeh, Abdolkarim; Modarresi-Alam, Ali Reza, E-mail: modaresi@chem.usb.ac.ir

2016-05-15

Poly [(±)-2-(sec-butyl) aniline]/silica-supported perchloric acid composites were synthesized by combination of poly[(±)-2-sec-butylaniline] base (PSBA) and the silica-supported perchloric acid (SSPA) as dopant solid acid in solid-state. The X-ray photoelectron spectroscopy (XPS) and CHNS results confirm nigraniline oxidation state and complete doping for composites (about 75%) and non-complete for the PSBA·HCl salt (about 49%). The conductivity of samples was (≈0.07 S/cm) in agreement with the percent of doping obtained of the XPS analysis. Also, contact resistance was determined by circular-TLM measurement. The morphology of samples by the scanning electron microscopy (SEM) and their coating were investigated by XPS, SEM-map and energy-dispersive X-ray spectroscopy (EDX). The key benefits of this work are the preparation of conductive chiral composite with the delocalized polaron structure under green chemistry and solid-state condition, the improvement of the processability by inclusion of the 2-sec-butyl group and the use of dopant solid acid (SSPA) as dopant. - Highlights: • The solid-state synthesis of the novel chiral composites of poly[(±)-2-(sec-butyl)aniline] (PSBA) and silica-supported perchloric acid (SSPA). • It takes 120 h for complete deprotonation of PSBA.HCl salt. • Use of SSPA as dopant solid acid for the first time to attain the complete doping of PSBA. • The coating of silica surface with PSBA.

Lead-Free Sn-Ce-O Composite Coating on Cu Produced by Pulse Electrodeposition from an Aqueous Acidic Sulfate Electrolyte

Science.gov (United States)

Sharma, Ashutosh; Das, Karabi; Das, Siddhartha

2017-10-01

Pulse-electrodeposited Sn-Ce-O composite solder coatings were synthesized on a Cu substrate from an aqueous acidic solution containing stannous sulfate (SnSO4·3H2O), sulfuric acid (H2SO4), and Triton X-100 as an additive. The codeposition was achieved by adding nano-cerium oxide powder in varying concentrations from 5 g/L to 20 g/L into the electrolytic bath. Microstructural characterization was carried out using x-ray diffraction (XRD), scanning electron microscopy, and transmission electron microscopy. The XRD analysis showed that the deposits consist mainly of tetragonal β (Sn) with reduced cerium oxide species. The composite coatings thus obtained exhibit a smaller grain size, possess higher microhardness, and a lower melting point than the monolithic Sn coating. The electrical resistivity of the developed composites increases, however, but lies within the permissible limits for current lead-free solder applications. Also, an optimum balance of properties in terms of microhardness, adhesion, melting point and resistivity can be obtained with 0.9 wt.% cerium oxide in the Sn matrix, which enables potential applications in solder joints and packaging.

Electron transport chains of lactic acid bacteria

NARCIS (Netherlands)

Brooijmans, R.J.W.

2008-01-01

Lactic acid bacteria are generally considered facultative anaerobic obligate fermentative bacteria. They are unable to synthesize heme. Some lactic acid bacteria are unable to form menaquinone as well. Both these components are cofactors of respiratory (electron transport) chains of prokaryotic

Coating composition curable by electron beam irradiation

International Nuclear Information System (INIS)

Masuda, Hiromasa; Iijima, Ken-ichi.

1971-01-01

Here is provided a coating composition curable with low dose of electron beams to give a smooth coating film having no surface tackiness. In one example, 126 parts of melamine was reacted with 682 parts of formalin followed by 697 parts of β-hydroxyethyl acrylate to produce component (A) (viscosity 780 cp). On the other hand, 900 parts of tung oil was reacted with 343 parts of maleic anhydride followed by 22 parts of dimethylaminoethyl methacrylate and 406 parts of β-hydroxyethyl acrylate. The resulting product was diluted with 508 parts of methyl methacrylate to give component (B) (dark red, viscous substance). 900 parts of (A), 100 parts of (B), 0.5 part of bees wax and 0.2 part of paraffin wax were blended together. A sized material was coated with the mixture and irradiated with electron beams (6 Mrad) in the presence of air. A smooth film free from surface tackiness was obtained. β-hydroxyethyl acrylate may be replaced by other hydroxyalkyl esters of α,β-unsaturated acids, and melamine may be replaced by urea, benzoguanamine or acetoguanamine. Tung oil may be replaced by linseed, safflower, soybean, rice, oiticica or cotton seed oil. A more flexible film is obtained by using component (B) in a larger proportion. (A)/(B) ratio should be in the range of 90/10 to 10/90 by wt. (Kaichi, S.)

A novel biodegradable nicotinic acid/calcium phosphate composite coating on Mg-3Zn alloy

Energy Technology Data Exchange (ETDEWEB)

Song, Yingwei, E-mail: ywsong@imr.ac.cn; Shan, Dayong; Han, En-Hou

2013-01-01

A novel biodegradable composite coating is prepared to reduce the biodegradation rate of Mg-3Zn alloy. The Mg-3Zn substrate is first immersed into 0.02 mol L{sup -1} nicotinic acid (NA) solution, named as vitamin B{sub 3}, to obtain a pretreatment film, and then the electrodeposition of calcium phosphate coating with ultrasonic agitation is carried out on the NA pretreatment film to obtain a NA/calcium phosphate composite coating. Surface morphology is observed by scanning electron microscopy (SEM). Chemical composition is determined by X-ray diffraction (XRD) and EDX. Protection property of the coatings is evaluated by electrochemical tests. The biodegradable behavior is investigated by immersion tests. The results indicate that a thin but compact bottom layer can be obtained by NA pretreatment. The electrodeposition calcium phosphate coating consists of many flake particles and ultrasonic agitation can greatly improve the compactness of the coating. The composite coating is biodegradable and can reduce the biodegradation rate of Mg alloys in stimulated body fluid (SBF) for twenty times. The biodegradation process of the composite coating can be attributed to the gradual dissolution of the flake particles into chippings. - Highlights: Black-Right-Pointing-Pointer NA/calcium phosphate composite coating is prepared to protect Mg-3Zn alloy implant. Black-Right-Pointing-Pointer Nicotinic acid (vitamin B{sub 3}) is available to obtain a protective bottom film. Black-Right-Pointing-Pointer Ultrasonic agitation greatly improves the compactness of calcium phosphate coating. Black-Right-Pointing-Pointer The composite coating can reduce the biodegradation rate of Mg-3Zn twenty times. Black-Right-Pointing-Pointer The composite coating is biodegraded by the dissolution of flakes into chippings.

Thermal properties of poly (lactic acid)/milkweed composites

Science.gov (United States)

Currently, most polymer composites utilize petroleum-based materials that are non-degradable and difficult to recycle or incur substantial cost for disposal. Green composites can be used in nondurable limited applications. In order to determine the degree of compatibility between Poly (lactic Acid...

Resonant electron capture by aspartame and aspartic acid molecules.

Science.gov (United States)

Muftakhov, M V; Shchukin, P V

2016-12-30

The processes for dissociative electron capture are the key mechanisms for decomposition of biomolecules, proteins in particular, under interaction with low-energy electrons. Molecules of aspartic acid and aspartame, i.e. modified dipeptides, were studied herein to define the impact of the side functional groups on peptide chain decomposition in resonant electron-molecular reactions. The processes of formation and decomposition of negative ions of both aspartame and aspartic acid were studied by mass spectrometry of negative ions under resonant electron capture. The obtained mass spectra were interpreted under thermochemical analysis by quantum chemical calculations. Main channels of negative molecular ions fragmentation were found and characteristic fragment ions were identified. The СООН fragment of the side chain in aspartic acid is shown to play a key role like the carboxyl group in amino acids and aliphatic oligopeptides. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Fatty acids composition of 10 microalgal species

Directory of Open Access Journals (Sweden)

Thidarat Noiraksar

2005-11-01

Full Text Available Fatty acids composition of 10 species of microalgae was determined at the exponential phase and the stationary phase. The microalgae consist of two species of diatoms, Bacillariophyceae, (Nitzschia cf. ovalis, Thalassiosira sp. five species of green microalgae, Prasinophyceae (Tetraselmis sp. and Chlorophyceae, (Dictyosphaerium pulchellum, Stichococcus sp., Chlorella sp., Scenedesmus falcatus and three species of blue green microalgae, Cyanophyceae (Anacystis sp., Synechococcus sp., Synechocystis sp..Medium for culture diatoms and green microalgae was F/2, and BG-11 media was used for Cyanophyceae. The microalgae were cultured beneath light intensity 143 μEm-2s-1, light: dark illustration 12:12 hrs., temperature 28ºC, and salinities 8-30 psu. The microalgae were harvested for analyzing fatty acid by centrivugal machine at 3500 rpm. for 5 min. at temperature 20ºC and stored at -80ºC prior to analysis.Fatty acids composition of microalgae differed from species to species. The majority fatty acids composition of diatoms at the exponential phase and the stationary phase were C16:1n-7 (17.12-31.47% and 28.22-42.02%, C16:0 (13.25-19.61% and 18.83-20.67%, C20:5 n-3 (16.65-26.67% and 11.32-23.68% respectively. The principle fatty acids composition of green microalgae, Prasinophyceae, Tetraselmis sp. were C18:3n-3 (16.17-16.67%, C16:0 (15.33-17.45%, C18:1n-9 (12.25-15.43%, C18:2n-6 (9.66-19.97%. The fatty acids composition of green microalgae, Chlorophyceae, were C18:3 n-3 (20.02-26.49% and 15.35- 30.63%, C16:0 (5.76-17.61% and 11.41-20.03%, C18:2n-6 (4.67-17.54% and 7.48-20.61% respectively. The major amounts of fatty acids content of blue green microalgae were C16:1n-7 (9.28-34.91% and 34.48- 35.04%, C14:0 (13.34-25.96% and 26.69-28.24%, C16:0 (5.89-29.15% and 5.70-16.81% except for Anacystis sp.which had a high amount of C18:3 n-3 (23.18-27.98% but low amount of C14:0 (3.66-4.98%.Bacillariophyceae contained the highest amount of highly unsaturated

Electron beam curing of polymer matrix composites

International Nuclear Information System (INIS)

Janke, C.J.; Wheeler, D.; Saunders, C.

1998-01-01

The purpose of the CRADA was to conduct research and development activities to better understand and utilize the electron beam PMC curing technology. This technology will be used to replace or supplement existing PMC thermal curing processes in Department of Energy (DOE) Defense Programs (DP) projects and American aircraft and aerospace industries. This effort involved Lockheed Martin Energy Systems, Inc./Lockheed Martin Energy Research Corp. (Contractor), Sandia National Laboratories, and ten industrial Participants including four major aircraft and aerospace companies, three advanced materials companies, and three electron beam processing organizations. The technical objective of the CRADA was to synthesize and/or modify high performance, electron beam curable materials that meet specific end-use application requirements. There were six tasks in this CRADA including: Electron beam materials development; Electron beam database development; Economic analysis; Low-cost Electron Beam tooling development; Electron beam curing systems integration; and Demonstration articles/prototype structures development. The contractor managed, participated and integrated all the tasks, and optimized the project efforts through the coordination, exchange, and dissemination of information to the project participants. Members of the Contractor team were also the principal inventors on several electron beam related patents and a 1997 R and D 100 Award winner on Electron-Beam-Curable Cationic Epoxy Resins. The CRADA achieved a major breakthrough for the composites industry by having successfully developed high-performance electron beam curable cationic epoxy resins for use in composites, adhesives, tooling compounds, potting compounds, syntactic foams, etc. UCB Chemicals, the world's largest supplier of radiation-curable polymers, has acquired a license to produce and sell these resins worldwide

Properties of polyvinyl alcohol/xylan composite films with citric acid.

Science.gov (United States)

Wang, Shuaiyang; Ren, Junli; Li, Weiying; Sun, Runcang; Liu, Shijie

2014-03-15

Composite films of xylan and polyvinyl alcohol were produced with citric acid as a new plasticizer or a cross-linking agent. The effects of citric acid content and polyvinyl alcohol/xylan weight ratio on the mechanical properties, thermal stability, solubility, degree of swelling and water vapor permeability of the composite films were investigated. The intermolecular interactions and morphology of composite films were characterized by FTIR spectroscopy and SEM. The results indicated that polyvinyl alcohol/xylan composite films had good compatibility. With an increase in citric acid content from 10% to 50%, the tensile strength reduced from 35.1 to 11.6 MPa. However, the elongation at break increased sharply from 15.1% to 249.5%. The values of water vapor permeability ranged from 2.35 to 2.95 × 10(-7)g/(mm(2)h). Interactions between xylan and polyvinyl alcohol in the presence of citric acid become stronger, which were caused by hydrogen bond and ester bond formation among the components during film forming. Copyright © 2013. Published by Elsevier Ltd.

The effect of conjugated linoleic acid on the fatty acid composition of ...

African Journals Online (AJOL)

The effect of conjugated linoleic acid on the fatty acid composition of different tissues and yolk lipids in pigeons. ... South African Journal of Animal Science ... Eight established breeding pairs per group were fed either a commercially pelleted pigeon diet mixed with 0.5% safflower oil (SFO) or 0.5% CLA for 12 weeks. For fatty ...

A convenient strategy to functionalize carbon nanotubes with ascorbic acid and its effect on the physical and thermomechanical properties of poly(amide–imide) composites

International Nuclear Information System (INIS)

Mallakpour, Shadpour; Zadehnazari, Amin

2014-01-01

Multi-walled carbon nanotubes (MWCNTs) were functionalized by ascorbic acid by a fast strategy under microwave irradiation to improve interfacial interactions and dispersion of CNTs in a poly(amide–imide) (PAI) matrix. This technique provides a rapid and economically viable route to produce covalently functionalized CNTs. The as-prepared, new type of functionalized CNTs were analyzed by several techniques. The thermal stabilities and mechanical interfacial properties of CNT/PAI composites were investigated using several techniques. The dispersion state of CNTs in the PAI matrix was observed by field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The mechanical interfacial property of the composites was significantly increased by the addition of ascorbic acid treated CNTs. The FE-SEM and TEM results showed that the separation and uniform dispersion of CNTs in the PAI matrix. The overview of these recent results is presented. -- Graphical abstract: Presentation of possible interactions of hydrogen bonding between the MWCNT-AS and the PAI chains. Highlights: • Surface functionalization of MWCNTs with ascorbic acid under microwave irradiation. • The MWCNT-AS/PAI composite films were fabricated by solution blending process. • Microstructure and MWCNT states in the composites were studied. • Thermal and mechanical properties of the composite films were evaluated. • Films of different contents of the MWCNTs-AS showed a superior tensile behavior

Preparation and thermal properties of form-stable palmitic acid/active aluminum oxide composites as phase change materials for latent heat storage

International Nuclear Information System (INIS)

Fang, Guiyin; Li, Hui; Cao, Lei; Shan, Feng

2012-01-01

Form-stable palmitic acid (PA)/active aluminum oxide composites as phase change materials were prepared by adsorbing liquid palmitic acid into active aluminum oxide. In the composites, the palmitic acid was used as latent heat storage materials, and the active aluminum oxide was used as supporting material. Fourier transformation infrared spectroscope (FT-IR), X-ray diffractometer (XRD) and scanning electronic microscope (SEM) were used to determine the chemical structure, crystalloid phase and microstructure of the composites, respectively. The thermal properties and thermal stability were investigated by a differential scanning calorimeter (DSC) and a thermogravimetry analyzer (TGA). The FT-IR analyses results indicated that there is no chemical interaction between the palmitic acid and active aluminum oxide. The SEM results showed that the palmitic acid was well adsorbed into porous network of the active aluminum oxide. The DSC results indicated that the composites melt at 60.25 °C with a latent heat of 84.48 kJ kg −1 and solidify at 56.86 °C with a latent heat of 78.79 kJ kg −1 when the mass ratio of the PA to active aluminum oxide is 0.9:1. Compared with that of the PA, the melting and solidifying time of the composites CPCM5 was reduced by 20.6% and 21.4% because of the increased heat transfer rate through EG addition. The TGA results showed that the active aluminum oxide can improve the thermal stability of the composites. -- Highlights: ► Form-stable PA/active aluminum oxide composites as PCMs were prepared. ► Chemical structure, crystalloid phase and microstructure of composites were determined. ► Thermal properties and thermal stability of the composites were investigated. ► Expanded graphite can improve thermal conductivity of the composites.

Process for producing a coating composition. [electron beam irradiation

Energy Technology Data Exchange (ETDEWEB)

Kimura, T; Harada, H; Kobayashi, S; Nakamoto, H; Sunano, K

1968-07-19

An easily hardenable acrylic coating composition is produced by irradiation with low energy electron beams to economize the industrial application of the composition. A polymer with molecular weights in the 5,000 to 500,000 range is composed of 1 to 40% by weight of a vinyl monomer containing a glycidyl radical, 30 to 99% of a methacrylic monomer and 0 to 69% of other copolymerizable vinyl monomers. This polymer dissolves in a monomer containing at least 30% of an acrylic monomer and 70% of other vinyl monomers. The reaction takes place between 0.1 to 1.0 mole of vinyl monomer containing a carboxyl radical and one mole of glycidyl radical in the solution. In an embodiment, 17.5% by weight of glycidyl methacrylate and 82.5% of alkyl acrylate are polymerized in suspension in the presence of a catalyst to form a bead like polymer with molecular weights in the 5,000 to 500,000 range. After 120 parts of the bead like polymer are dissolved in 180 parts of the acrylic monomer in the presence of a polymerization inhibitor by heating, 22 parts of ..cap alpha.., ..beta..- unsaturated monocarboxylic acid are added to the solution to react with the glycidyl radical, whereby a non-solvent type coating material containing the polymer having a vinyl radical side chain is produced. In the place of the catalyst, electron beams can be used at an energy level of 0.1 to 20 MeV. The dose rate may be in the range of 0.1 to 2.0 Mrad/sec.

Fatty acid and cholesterol content, chemical composition and ...

African Journals Online (AJOL)

This study aimed to determine the fatty acid and chemical composition and cholesterol concentration of horsemeat, and to evaluate its taste acceptability by the Brazilian population. Horsemeat samples (M. longissimus dorsi) were obtained from a Paraná State slaughterhouse. The chemical composition revealed a low lipid ...

Through-thickness thermal conductivity enhancement of graphite film/epoxy composite via short duration acidizing modification

Science.gov (United States)

Wang, Han; Wang, Shaokai; Lu, Weibang; Li, Min; Gu, Yizhou; Zhang, Yongyi; Zhang, Zuoguang

2018-06-01

Graphite films have excellent in-plane thermal conductivity but extremely low through-thickness thermal conductivity because of their intrinsic inter-layer spaces. To improve the inter-layer heat transfer of graphite films, we developed a simple interfacial modification with a short duration mixed-acid treatment. The effects of the mixture ratio of sulfuric and nitric acids and treatment time on the through-thickness thermal properties of graphite films were studied. The modification increased the through-thickness thermal conductivity by 27% and 42% for the graphite film and its composite, respectively. X-ray photoelectron spectroscopy, X-ray powder diffraction, and scanning electron microscopy results indicated that the acidification process had two competing effects: the positive contribution made by the enhanced interaction between the graphite layers induced by the functional groups and the negative effect from the destruction of the graphite layers. As a result, an optimal acidification method was found to be sulfuric/nitric acid treatment with a mixture ratio of 3:1 for 15 min. The resultant through-thickness thermal conductivity of the graphite film could be improved to 0.674 W/mK, and the corresponding graphite/epoxy composite shows a through-thickness thermal conductivity of 0.587 W/mK. This method can be directly used for graphite films and their composite fabrication to improve through-thickness thermal conductivity.

Influence of Maleic Anhydride/Glycidyl Methacrylate Cografted Polylactic Acid on Properties of Wood Flour/PLA Composites

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DU Jun

2017-12-01

Full Text Available Graft copolymers of PLA-g-MAH, PLA-g-GMA and PLA-co-MAH/GMA were prepared by means of melt grafting. The structure of the graft copolymers were characterized by FTIR.Wood flour/PLA composites were prepared by injection molding with three kinds of graft copolymers as compatibilizers, and the fractured morphology of composites was investigated by scanning electron microscope (SEM. Results show that there is no obvious phase interface between wood flour and PLA,which indicating the interfacial compatibility of wood flour/PLA composites is improved after adding different graft copolymers. The determination results of mechanical properties, processing flowability and dynamic rheological property of composites prepared with different graft copolymers reveal that, compared to the composite without compatibilizer, the tensile strength and impact strength of wood flour/PLA composites are increased by 9.54% and 7.23% respectively, and the equilibrium torque, shear heat, storage modulus and complex viscosity are all increased after adding maleic anhydride/glycidyl methacrylate cografted polylactic acid.

Detecting Electron Transport of Amino Acids by Using Conductance Measurement

Directory of Open Access Journals (Sweden)

Wei-Qiong Li

2017-04-01

Full Text Available The single molecular conductance of amino acids was measured by a scanning tunneling microscope (STM break junction. Conductance measurement of alanine gives out two conductance values at 10−1.85 G0 (1095 nS and 10−3.7 G0 (15.5 nS, while similar conductance values are also observed for aspartic acid and glutamic acid, which have one more carboxylic acid group compared with alanine. This may show that the backbone of NH2–C–COOH is the primary means of electron transport in the molecular junction of aspartic acid and glutamic acid. However, NH2–C–COOH is not the primary means of electron transport in the methionine junction, which may be caused by the strong interaction of the Au–SMe (methyl sulfide bond for the methionine junction. The current work reveals the important role of the anchoring group in the electron transport in different amino acids junctions.

Calibration of a lactic-acid model for simulating biofilm-induced degradation of the dentin-composite interface.

Science.gov (United States)

Zhu, Laikuan; Li, Yuping; Carrera, Carola A; Chen, Yung-Chung; Li, Mingyu; Fok, Alex

2017-11-01

To verify and calibrate a chemical model for simulating the degradation of the dentin-composite interface induced by multi-species oral biofilms in vitro. Dentin-composite disks (5-mm dia.×2-mm thick) were made from bovine incisor roots and filled with either Z100™ (Z100) or Filtek™ LS (LS) composite. The disks, which were covered with nail varnish, but with one of the dentin-composite margins exposed, were immersed in lactic acid solution at pH 4.5 for up to 48h. Diametral compression was performed to measure the reduction in bond strength of the dentin-composite disks following acid challenge. Scanning electron microscopy (SEM) was used to examine decalcification of dentin and fracture modes of the disks. To better understand the degradation process, micro-computed tomography, in combination with a radiopaque dye (AgNO 3 ), was used to assess interfacial leakage in 3D longitudinally, while SEM was used to determine the path of leakage. One-way analysis of variance (ANOVA) was used to analyze the results, with the level of statistical significance set at pcomposite interface, instead. The degree of dentin demineralization, the reduction in debonding load and the modes of failure observed were very similar to those induced by multi-species oral biofilms found in the previous work. Leakage of AgNO 3 occurred mainly along the hybrid layer. The specimens filled with Z100 had a thicker hybrid layer (∼6.5μm), which exhibited more interfacial leakage than those filled with LS. The chemical model with lactic acid used in this study can induce degradation to the dentin-composite interface similar to those produced by multi-species biofilms. With appropriate calibration, this could provide an effective in vitro method for ageing composite restorations in assessing their potential clinical performance. Copyright © 2017 The Academy of Dental Materials. All rights reserved.

Preparation of poly (styrene)-b-poly (acrylic acid)/{gamma}-Fe{sub 2}O{sub 3} composites

Energy Technology Data Exchange (ETDEWEB)

Zhang, L.D. [School of Materials Science and Engineering, Shandong Polytechnic University, Key Laboratory of Processing and Testing Technology of Glass Functional Ceramics of Shandong Province, Daxue Road, Western University Science Park, Jinan 250353 (China); Liu, W.L., E-mail: wlliu@sdu.edu.cn [School of Materials Science and Engineering, Shandong Polytechnic University, Key Laboratory of Processing and Testing Technology of Glass Functional Ceramics of Shandong Province, Daxue Road, Western University Science Park, Jinan 250353 (China); Xiao, C.L.; Yao, J.S.; Fan, Z.P.; Sun, X.L.; Zhang, X.; Wang, L. [School of Materials Science and Engineering, Shandong Polytechnic University, Key Laboratory of Processing and Testing Technology of Glass Functional Ceramics of Shandong Province, Daxue Road, Western University Science Park, Jinan 250353 (China); Wang, X.Q. [State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100 (China)

2011-12-15

The use of a block copolymer, poly (styrene)-b-poly (acrylic acid) (PS-b-PAA) to prepare a magnetic nanocomposite was investigated. Poly (styrene)-poly (t-butyl acrylate) block copolymer, being synthesized by atom transfer radical polymerization, was hydrolyzed with hydrochloric acid for obtaining PS-b-PAA. The obtained PS-b-PAA was then compounded with the modified {gamma}-Fe{sub 2}O{sub 3}, and subsequently the magnetic nanocomposite was achieved. The products were characterized by {sup 1}H NMR, FTIR, gel permeation chromatography, thermogravimetric analysis, transmission electron microscopy and vibrating sample magnetometer. The results showed that the nanocomposites exhibited soft magnetism, with the mean diameter of 100 nm approximately. - Highlights: > Magnetic composites were prepared using {gamma}-Fe{sub 2}O{sub 3} and PS-b-PAA. > PS-b-PAA was synthesized by atom transfer radical polymerization. > The obtained composite exhibited soft magnetism.

Fatty acid esters-based composite phase change materials for thermal energy storage in buildings

International Nuclear Information System (INIS)

Sarı, Ahmet; Karaipekli, Ali

2012-01-01

In this study, fatty acid esters-based composite phase change materials (PCMs) for thermal energy storage were prepared by blending erythritol tetrapalmitate (ETP) and erythritol tetrastearate (ETS) with diatomite and expanded perlite (EP). The maximum incorporation percentage for ETP and ETS into diatomite and EP was found to be 57 wt% and 62 wt%, respectively without melted PCM seepage from the composites. The morphologies and compatibilities of the composite PCMs were structurally characterized using scanning electron microscope (SEM) and Fourier transformation infrared (FT–IR) analysis techniques. Thermal energy storage properties of the composite PCMs were determined by differential scanning calorimetry (DSC) analysis. The DSC analyses results indicated that the composite PCMs were good candidates for building applications in terms of their large latent heat values and suitable phase change temperatures. The thermal cycling test including 1000 melting and freezing cycling showed that composite PCMs had good thermal reliability and chemical stability. TG analysis revealed that the composite PCMs had good thermal durability above their working temperature ranges. Moreover, in order to improve the thermal conductivity of the composite PCMs, the expanded graphite (EG) was added to them at different mass fractions (2%, 5%, and 10%). The best results were obtained for the composite PCMs including 5wt% EG content in terms of the increase in thermal conductivity values and the decrease amount in latent heat capacity. The improvement in thermal conductivity values of ETP/Diatomite, ETS/Diatomite, ETP/EP and ETS/EP were found to be about 68%, 57%, 73% and 75%, respectively. Highlights: ► Fatty acid esters-based composite PCMs were prepared by blending ETP and ETS with diatomite and expanded perlite. ► The composite PCMs were characterized by using SEM, FT–IR, DSC and TG analysis methods. ► The DSC results indicated that the composites PCMs had good thermal

Interface electron structure of Fe3Al/TiC composites

Institute of Scientific and Technical Information of China (English)

PANG Lai-xue; SUN Kang-ning; SUN Jia-tao; FAN Run-hua; REN Shuai

2006-01-01

Based on YU's solids and molecules emperical electron theory(EET), interface valence electron structure of TiC-Fe3Al composites was set up, and the valence electron density of different atomic states TiC and Fe3Al composites in various planes was determined. The results indicate that the electron density of (100)Fe3Al is consistent with that of (110)TiC in the first-class approximation, the absolute value of minimum electron density difference along the interface is 0.007 37 nm-2, and the relative value is 0.759%. (110)TiC//(100)Fe3Al preferred orientation is believed to benefit the formation of the cuboidal shape TiC. In the other hand, it shows that the particle growth is accompanied by the transport of electron, the deviation continuity of electron density intrinsically hinders the grain growth. The electron density of (100)TiC is not consistent with Fe3Al arbitrary crystallographic plane,thus it well explains that the increased titanium and carbon contents do not increase the size of large particles. The crystallographic orientation of (110)TiC//(100)FeAl will improve the mechanical properties. Therefore interface electron theory is an effective theoretical implement for designing excellent property of composites.

Fatty acid composition of ostrich (Struthio camelus abdominal adipose tissue

Directory of Open Access Journals (Sweden)

Daniela Belichovska

2015-03-01

Full Text Available Fatty acid composition of foods has a great impact on nutrition and health. Therefore, thе determination and knowledge of the fatty acid composition of food is very important for nutrition. Due to the high nutritional characteristics of ostrich meat and its products, the research determining their quality is of topical interest. The aim of the present investigation was the determination of fatty acid composition of ostrich adipose tissue. The content of fatty acids was determined according to AOAC Official Methods of Analysis and determination was performed using a gas chromatograph with a flame-ionization detector (GC-FID. The results are expressed as a percentage of the total content of fatty acids. The method was validated and whereupon the following parameters were determined: linearity, precision, recovery, limit of detection and limit of quantification. The repeatability was within of 0.99 to 2.15%, reproducibility from 2.01 to 4.57%, while recovery ranged from 94.89 to 101.03%. According to these results, this method is accurate and precise and can be used for analysis of fatty acids in foods. It was concluded that the content of saturated fatty acids (SFA accounted 34.75%, of monounsaturated fatty acids (MUFA 38.37%, of polyunsaturated fatty acids (PUFA 26.88%, of total unsaturated fatty acids (UFA 65.25% and of desirable fatty acids (DFA (total unsaturated + stearic acid 70.37% of the analysed samples. The ratio polyunsaturated/saturated fatty acids accounted 0.77. The most present fatty acid is the oleic (C18:1n9c with 28.31%, followed by palmitic (C16:0 with 27.12% and linoleic (C18:2n6c acid with 25.08%. Other fatty acids are contained in significantly lower quantities.

Radiation-induced crosslinking and post-processing of poly(L-lactic acid) composite

International Nuclear Information System (INIS)

Nagasawa, Naotsugu; Kasai, Noboru; Yagi, Toshiaki; Yoshii, Fumio; Tamada, Masao

2011-01-01

Poly(L-lactic acid), PLLA, was irradiated using electron beams (EBs) in the presence of triallyl isocyanurate (TAIC) at 5% concentration as crosslinking agent. The crosslinked PLLA obtained has heat resistance, as demonstrated by retention of its original shape at glass transition temperature or even higher than 200 o C. As an application of this fact, crosslinked PLLA is applied in spectacle lens to prevent shape deformation of eyeglass frames in displaying and transporting. However, in this application to lens, it is not enough to improve the thermal deformation of PLLA under stress at 70 o C. Radiation-induced crosslinking of a PLLA/silicon dioxide (SiO 2 ) composite with TAIC and post-processing of the crosslinked PLLA composite by heating were further investigated from the viewpoint of thermal deformation. The PLLA materials have several advantages such as high heat resistance and transparency. It is therefore proved that the combination of radiation-induced crosslinking, composition of SiO 2 and post-heating is beneficial for expanding the applications of PLLA.

Radiation-induced crosslinking and post-processing of poly(L-lactic acid) composite

Energy Technology Data Exchange (ETDEWEB)

Nagasawa, Naotsugu, E-mail: nagasawa.naotsugu@jaea.go.j [Japan Atomic Energy Agency (JAEA), Quantum Beam Science Directorate, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Kasai, Noboru; Yagi, Toshiaki; Yoshii, Fumio; Tamada, Masao [Japan Atomic Energy Agency (JAEA), Quantum Beam Science Directorate, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

2011-02-15

Poly(L-lactic acid), PLLA, was irradiated using electron beams (EBs) in the presence of triallyl isocyanurate (TAIC) at 5% concentration as crosslinking agent. The crosslinked PLLA obtained has heat resistance, as demonstrated by retention of its original shape at glass transition temperature or even higher than 200 {sup o}C. As an application of this fact, crosslinked PLLA is applied in spectacle lens to prevent shape deformation of eyeglass frames in displaying and transporting. However, in this application to lens, it is not enough to improve the thermal deformation of PLLA under stress at 70 {sup o}C. Radiation-induced crosslinking of a PLLA/silicon dioxide (SiO{sub 2}) composite with TAIC and post-processing of the crosslinked PLLA composite by heating were further investigated from the viewpoint of thermal deformation. The PLLA materials have several advantages such as high heat resistance and transparency. It is therefore proved that the combination of radiation-induced crosslinking, composition of SiO{sub 2} and post-heating is beneficial for expanding the applications of PLLA.

Fatty acid composition and amino acid profile of two freshwater ...

African Journals Online (AJOL)

The proximate, fatty and amino acids composition of two commercially important freshwater fish species Clarias gariepinus and Tilapia zillii. purchased from local fishermen in two landing sites in Lagos State, Nigeria were determined. Live specimens of C. gariepinus were purchased while samples of T. zillii were stored in ...

Apple juice composition: sugar, nonvolatile acid, and phenolic profiles.

Science.gov (United States)

Lee, H S; Wrolstad, R E

1988-01-01

Apples from Michigan, Washington, Argentina, Mexico, and New Zealand were processed into juice; the 8 samples included Golden Delicious, Jonathan, Granny Smith, and McIntosh varieties. Liquid chromatography was used for quantitation of sugars (glucose, fructose, sucrose, and sorbitol), nonvolatile acids (malic, quinic, citric, shikimic, and fumaric), and phenolics (chlorogenic acid and hydroxymethylfurfural [HMF]). Other determinations included pH, 0Brix, and L-malic acid. A number of compositional indices for these authentic juices, e.g., chlorogenic acid content, total malic - L-malic difference, and the HMF:chlorogenic ratio, were at variance with recommended standards. The phenolic profile was shown to be particularly influenced by gelatin fining, with peak areas decreasing by as much as 50%. The L-malic:total malic ratio serves as a better index for presence of synthetic malic acid than does the difference between the 2 determinations. No apparent differences in chemical composition could be attributed to geographic origin.

Effect of Cooking Method on the Proximate, Amino Acid and Fatty Acid Compositions of Clarias gariepinus and Oreochromis niloticus

Directory of Open Access Journals (Sweden)

Omolara Olusola Oluwaniyi

2016-10-01

Full Text Available The proximate, amino acid and fatty acid compositions of the fillet and oil from Clarias gariepinus (Catfish and Oreochromis niloticus (Tilapia were determined. The moisture content ranged from 76.27 % for catfish to 79.97 % for tilapia while the oil content ranged from 7.80 % for tilapia and 11.00 % for catfish. Ash content was in the range 8.03 – 9.16 % and the protein content was 15.83 - 18.48 %. Cooking – boiling, roasting or frying – resulted in a variation in the nutrient composition but with no significant effect on the amino acid composition except for the samples fried with palm oil which resulted in significantly reduced essential amino acids contents. All the fish samples – both fresh and processed – have amino acid scores less than 100, with lysine, threonine and the sulphur-containing amino acids being among the limiting amino acids. Both fish samples contain more unsaturated than saturated fatty acids.

Composition of fatty acids in selected vegetable oils

OpenAIRE

Helena Frančáková; Eva Ivanišová; Štefan Dráb; Tomáš Krajčovič; Marián Tokár; Ján Mareček; Janette Musilová

2015-01-01

Plant oils and fats are important and necessary components of the human nutrition. They are energy source and also contain fatty acids - compounds essential for human health. The aim of this study was to evaluate nutritional quality of selected plant oil - olive, rapeseed, pumpkin, flax and sesame; based on fatty acid composition in these oils. Fatty acids (MUFA, PUFA, SFA) were analyzed chromatography using system Agilent 6890 GC, injector multimode, detector FID. The highest c...

Radiation-induced electron migration in nucleic acids

International Nuclear Information System (INIS)

Fuciarelli, A.F.; Sisk, E.C.; Miller, J.H.; Zimbrick, J.D.

1994-01-01

Radiation-induced electron migration along DNA is a mechanism by which randomly produced stochastic energy deposition events can lead to non-random types of damage along DNA manifested distal to the sites of the initial energy deposition. Radiation-induced electron migration in nucleic acids has been examined using oligonucleotides containing 5-bromouracil (5-BrU). Interaction of 5-BrU with solvated electrons results in release of bromide ions and formation of uracil-5-yl radicals. Monitoring either bromide ion release or uracil formation provides an opportunity to study electron migration processes in model nucleic acid systems. Using this approach we have discovered that electron migration along oligonucleotides is significantly influenced by the base sequence and strandedness. Migration along 7 base pairs in oligonucleotides containing guanine bases was observed for oligonucleotides irradiated in solution, which compares with mean migration distances of 6-10 bp for Escherichia coli DNA irradiated in solution and 5.5 bp for E. coli DNA irradiated in cells. Evidence also suggests that electron migration can occur preferentially in the 5' to 3' direction along a double-stranded oligonucleotide containing a region of purine bases adjacent to the 5-BrU moiety. Our continued efforts will provide information regarding the contribution of electron transfer along DNA to formation of locally multiply damaged sites created in DNA by exposure to ionizing radiation. (Author)

The Usability of Boric Acid as an Alternative Foaming Agent on the Fabrication of Al/Al2O3 Composite Foams

Science.gov (United States)

Yaman, Bilge; Onuklu, Eren; Korpe, Nese O.

2017-09-01

Pure Al and alumina (2, 5, 10 wt.% Al2O3)-added Al composite foams were fabricated through powder metallurgy technique, where boric acid (H3BO3) is employed as a new alternative foaming agent. It is aimed to determine the effects of boric acid on the foaming behavior and cellular structure and also purposed to develop the mechanical properties of Al foams by addition of Al2O3. Al and Al composite foams with porosity fraction in the range of 46-53% were achieved by sintering at 620 °C for 2 h. Cell morphology was characterized using a combination of stereomicroscope equipped with image analyzer and scanning electron microscopy. Microhardness values were measured via using Vickers indentation technique. Quasi-static compression tests were performed at strain rate of 10-3 s-1. Compressive strength and energy absorption of the composite foams enhanced not only by the increasing weight fraction of alumina, but also by the usage of boric acid which leads to formation of boron oxide (B2O3) acting as a binder in obtaining dense cell walls. The results revealed that the boric acid has outstanding potential as foaming agent in the fabrication of Al and Al composite foams by providing improved mechanical properties.

Drought and heat stress effects on soybean fatty acid composition and oil stability

Science.gov (United States)

Previous studies have shown that oil concentration and fatty acid profile (composition) change with genotype, environment (mainly heat and drought), and geographical location. The changes in fatty acid composition under these conditions affect fatty acid stability, creating a challenge to oil proces...

[Effect of total hypothermia on the fatty acid composition of blood phospholipids of rats and sousliks and light irradiation on chemical processes in lipid extract].

Science.gov (United States)

Zabelinskiĭ, S A; Chebotareva, M A; Kalandarov, A M; Feĭzulaev, B A; Klichkhanov, N K; Krivchenko, A I; Kazennov, A M

2011-01-01

Effect of hypothermia on the fatty acid composition of rat and souslik blood phospholipids is studied. Different reaction of these animals to cooling is revealed: in rats no changes were observed in the fatty acid composition of blood phospholipids, whereas in the hibernating there were significant changes in the content of individual fatty acids (FA). The content of monoenic acids in sousliks decreased almost by 50%, while the content of saturated acid (C18) and of polyenic acids C18 : 2omega6 and C20 : 4omega6 rose significantly. Such changes seem to be the mechanism that promotes maintenance of the organism viability under conditions of a decreased level of metabolism, heart rhythm, and body temperature and is evolutionarily acquired. At the same time, the observed changes in the content of individual FA do not lead to sharp changes in such integrative parameters as the total non-saturation of phospholipids, which determines liquid properties of chylomicrons and other lipolipoprotein transport particles of the souslik blood. There are studied absorption spectra of blood lipid extracts of rats and sousliks under effect of light as well as effect of light upon the FA composition of lipid extracts of these animals. The FA composition of lipid extracts has been established to remain practically constant, whereas the character of changes of spectra under action of light indicates the presence in the extracts of oxidation-reduction reactions. The obtained data allow suggesting that in the lipid extract there occurs cooperation both of the phospholipid molecules themselves and of them with other organic molecules, which makes it possible for fatty acids to participate in processes of transport both of electrons and of protons. This novel role of FA as a participant of the electron transfer might probably be extrapolated to chemical reactions (processes) occurring inside the membrane.

Thermochemical stability of zirconia-titanium nitride as mixed ionic-electronic composites

DEFF Research Database (Denmark)

Silva, P. S. M.; Esposito, V.; Marani, D.

2018-01-01

Dense zirconia (8% molar yttria-stabilized ZrO2)-titanium nitride (TiN) composites are fabricated to obtain mixed ionic-electronic conducting ceramic systems with high degree of electronic and thermal conductivity. The composites are consolidated by spark plasma sintering (SPS), starting from pure...... the composites, high electrical conductivity is attained. Samples exhibit metallic behavior, showing an unexpected percolation of TiN in the YSZ matrix for volume fraction ≤ 25 wt% (27 vol%). Chemical degradation and electrical properties of the compounds were monitored under oxidative (air) and inert (Ar...... transport properties of the composite can be tuned by both the relative volume fraction of phases and controlled oxidative treatments. Adjusting such parameters different electric behaviors were observed ranging from predominant electronic conductors, to temperature-independent resistivity...

Nanodiamond composite as a material for cold electron emitters

International Nuclear Information System (INIS)

Arkhipov, A V; Sominski, G G; Uvarov, A A; Gordeev, S K; Korchagina, S B

2008-01-01

Characteristics of field-induced electron emission were investigated for one of newly designed all-carbon materials - nanodiamond composite (NDC). The composite is comprised by 4-6 nm diamond grains covered with 0.2-1 nm-thick graphite-like shells that merge at grain junctions and determine such properties as mechanical strength and high electric conductivity. Large number of uniformly distributed sp 3 -sp 2 interfaces allowed to expect enhanced electron emission in electric field. Combination of these features makes NDC a promising material for cold electron emitters in various applications. Experimental testing confirmed high efficiency of electron emission from NDC. In comparison with previousely tested forms of nanocarbon, NDC emitters demonstrated better stabily and tolerance to performance conditions. Unusual activation scenarios and thermal dependencies of emission characteristics observed in experiments with NDC can add new background for explanation of facilitated electron emission from nanocarbons with relatively 'smooth' surface morphology

Impact of dietary fatty acids on muscle composition, liver lipids, milt composition and sperm performance in European eel

DEFF Research Database (Denmark)

Butts, Ian; Baeza, R.; Støttrup, Josianne

2015-01-01

of dietary regime on muscle composition, and liver lipids prior to induced maturation, and the resulting sperm composition and performance. To accomplish this fish were reared on three "enhanced" diets and one commercial diet, each with different levels of fatty acids, arachidonic acid (ARA......), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). Neutral lipids from the muscle and liver incorporated the majority of the fatty acid profile, while phospholipids incorporated only certain fatty acids. Diet had an effect on the majority of sperm fatty acids, on the total volume of extractable milt...... induced medium milt volumes but had the highest sperm motility. EPA also seems important for sperm quality parameters since diets with higher EPA percentages had a higher volume of milt and higher sperm motility. In conclusion, dietary fatty acids had an influence on fatty acids in the tissues of male eel...

Meat quality and intramuscular fatty acid composition of Catria Horse.

Science.gov (United States)

Trombetta, Maria Federica; Nocelli, Francesco; Pasquini, Marina

2017-08-01

In order to extend scientific knowledge on autochthonous Italian equine meat, the physical-chemical parameters of Catria Horse Longissimus thoracis (LT) muscle and its nutritional characteristics have been investigated. Ten steaks of Catria foal raised at pasture and fattened indoors for 2 months were dissected, and LT muscle was analyzed for chemical composition, total iron, drip loss, colorimetric characteristics, intramuscular fat, fatty acid profile and nutritional indexes. Steak dissection showed that LT muscle accounted for 36.78% and fat accounted for 9.19% of weight of steak. Regarding chemical composition, protein and fat content was 20.31% and 2.83%, respectively. Total iron content (1.95 mg/100 g) was lower than data reported in the literature. Color parameters showed a luminous and intense red hue muscle. The sum of unsaturated fatty acid composition (50.3%) was higher than the sum of saturated fatty acids (46.64 %). The fatty acid profile and nutritional values of Catria Horse meat could be modified adopting extensive rearing systems and grazing. The data suggests that further investigation on the composition of Catria Horse meat should be carried out to valorize this autochthonous breed, reared in sustainable livestock systems, and its meat in local short-chain systems. © 2016 Japanese Society of Animal Science.

The effect of sulfuric acid on pore initiation in anodic alumina formed in oxalic acid

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Behnam Hafezi

2014-07-01

Full Text Available In this work, a tracer study on pore initiation in anodic alumina in oxalic acid was performed. Effects of some experimental parameters such as applied electrical potential, electrolyte composition and heat pretreatment were evaluated. Electrochemical and morphological experiments were performed using potentiostatic anodizing and scanning electron microscopy (SEM techniques, respectively. Effect of electrolyte composition on current density was discussed. In various electrical potentials, electrolyte composition had different effects on current density. Addition of sulfuric acid into oxalic acid increased porosity. Also, distribution of pore size and pore diameter were influenced by presence of sulfuric acid. Effect of electrolyte composition on the morphology of aluminum surface layer depended on the electric potential. Current density and porosity of aluminum surface layer was decreased by heat pretreatment.

Preparation, morphology and thermal properties of electrospun fatty acid eutectics/polyethylene terephthalate form-stable phase change ultrafine composite fibers for thermal energy storage

International Nuclear Information System (INIS)

Cai Yibing; Ke Huizhen; Lin Liang; Fei Xiuzhu; Wei Qufu; Song Lei; Hu Yuan; Fong Hao

2012-01-01

Highlights: ► Electrospun binary fatty acid eutectics/PET ultrafine composite fibers were prepared. ► Fatty acid eutectics had appropriate phase transition temperature and heat enthalpy. ► Their morphological structures and thermal properties were different from each other. ► Composite fibers could be innovative form-stable PCMs for thermal energy storage. - Abstract: The ultrafine composite fibers based on the composites of binary fatty acid eutectics and polyethylene terephthalate (PET) with varied fatty acid eutectics/PET mass ratios (50/100, 70/100, 100/100 and 120/100) were fabricated using the technique of electrospinning as form-stable phase change materials (PCMs). The five binary fatty acid eutectics including LA–MA, LA–PA, MA–PA, MA–SA and PA–SA were prepared according to Schrader equation, and then were selected as an innovative type of solid–liquid PCMs. The results characterized by differential scanning calorimeter (DSC) indicated that the prepared binary fatty acid eutectics with low phase transition temperatures and high heat enthalpies for climatic requirements were more suitable for applications in building energy storage. The structural morphologies, thermal energy storage and thermal stability properties of the ultrafine composite fibers were investigated by scanning electron microscope (SEM), DSC and thermogravimetric analysis (TGA), respectively. SEM images revealed that the electrospun binary fatty acid eutectics/PET ultrafine composite fibers possessed the wrinkled surfaces morphologies compared with the neat PET fibers with cylindrical shape and smooth surfaces; the grooves or ridges on the corrugated surface of the ultrafine composite fibers became more and more prominent with increasing fatty acid eutectics amount in the composite fibers. The fibers with the low mass ratio maintained good structural morphologies while the quality became worse when the mass ratio is too high (more than 100/100). DSC measurements

Effect of supplementation of arachidonic acid (AA) or a combination of AA plus docosahexaenoic acid on breastmilk fatty acid composition

NARCIS (Netherlands)

Smit, EN; Koopmann, M; Boersma, ER; Muskiet, FAJ

We investigated whether supplementation with arachidonic acid (20:4 omega 6; AA), ora combination of AA and docosahexaenoic acid (22:6 omega 3; DHA) would affect human milk polyunsaturated fatty acid (PUFA) composition. Ten women were daily supplemented with 300 mg AA, eight with 300 mg AA, 110 mg

Evaluation of Fatty Acid and Amino Acid Compositions in Okra (Abelmoschus esculentus Grown in Different Geographical Locations

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Rokayya Sami

2013-01-01

Full Text Available Okra has different uses as a food and a remedy in traditional medicine. Since it produces many seeds, distribution of the plant is also quite easy. Although seed oil yield is low (4.7%, since the linoleic acid composition of the seed oil is quiet high (67.5%, it can still be used as a source of (UNSAT unsaturated fatty acids. In this study, samples of okra grown in four different locations were analyzed to measure fatty acid and amino acid compositions. The content of the lipid extraction ranged from 4.34% to 4.52% on a dry weight basis. Quantitatively, the main okra fatty acids were palmitic acid (29.18–43.26%, linoleic acid (32.22–43.07%, linolenic acid (6.79–12.34%, stearic acid (6.36–7.73%, oleic acid (4.31–6.98%, arachidic acid (ND–3.48%, margaric acid (1.44–2.16%, pentadecylic acid (0.63–0.92%, and myristic acid (0.21–0.49%. Aspartic acid, proline, and glutamic acids were the main amino acids in okra pods, while cysteine and tyrosine were the minor amino acids. Statistical methods revealed how the fatty acid and amino acid contents in okra may be affected by the sampling location.

Serum Paraoxonase 1 Activity Is Associated with Fatty Acid Composition of High Density Lipoprotein

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Maryam Boshtam

2013-01-01

Full Text Available Introduction. Cardioprotective effect of high density lipoprotein (HDL is, in part, dependent on its related enzyme, paraoxonase 1 (PON1. Fatty acid composition of HDL could affect its size and structure. On the other hand, PON1 activity is directly related to the structure of HDL. This study was designed to investigate the association between serum PON1 activity and fatty acid composition of HDL in healthy men. Methods. One hundred and forty healthy men participated in this research. HDL was separated by sequential ultracentrifugation, and its fatty acid composition was analyzed by gas chromatography. PON1 activity was measured spectrophotometrically using paraxon as substrate. Results. Serum PON1 activity was directly correlated with the amount of stearic acid and dihomo-gamma-linolenic acid (DGLA. PON1/HDL-C was directly correlated with the amount of miristic acid, stearic acid, and DGLA and was inversely correlated with total amount of ω6 fatty acids of HDL. Conclusion. The fatty acid composition of HDL could affect the activity of its associated enzyme, PON1. As dietary fats are the major determinants of serum lipids and lipoprotein composition, consuming some special dietary fatty acids may improve the activity of PON1 and thereby have beneficial effects on health.

Serum paraoxonase 1 activity is associated with fatty acid composition of high density lipoprotein.

Science.gov (United States)

Boshtam, Maryam; Razavi, Amirnader Emami; Pourfarzam, Morteza; Ani, Mohsen; Naderi, Gholam Ali; Basati, Gholam; Mansourian, Marjan; Dinani, Narges Jafari; Asgary, Seddigheh; Abdi, Soheila

2013-01-01

Cardioprotective effect of high density lipoprotein (HDL) is, in part, dependent on its related enzyme, paraoxonase 1 (PON1). Fatty acid composition of HDL could affect its size and structure. On the other hand, PON1 activity is directly related to the structure of HDL. This study was designed to investigate the association between serum PON1 activity and fatty acid composition of HDL in healthy men. One hundred and forty healthy men participated in this research. HDL was separated by sequential ultracentrifugation, and its fatty acid composition was analyzed by gas chromatography. PON1 activity was measured spectrophotometrically using paraxon as substrate. Serum PON1 activity was directly correlated with the amount of stearic acid and dihomo-gamma-linolenic acid (DGLA). PON1/HDL-C was directly correlated with the amount of miristic acid, stearic acid, and DGLA and was inversely correlated with total amount of ω 6 fatty acids of HDL. The fatty acid composition of HDL could affect the activity of its associated enzyme, PON1. As dietary fats are the major determinants of serum lipids and lipoprotein composition, consuming some special dietary fatty acids may improve the activity of PON1 and thereby have beneficial effects on health.

Amino acid and fatty acid compositions of Rusip from fermented Anchovy fish (Stolephorussp)

Science.gov (United States)

Koesoemawardani, D.; Hidayati, S.; Subeki

2018-04-01

Rusip is a typical food of Bangka Belitung Indonesia made from fermented anchovy. This study aims to determine the properties of chemistry, microbiology, composition of amino acids and fatty acids from fermented fish spontaneously and non spontaneously. Spontaneous rusip treatment is done by anchovy fish (Stolephorussp) after cleaning and added salt 25% (w/w) and palm sugar 10% (w/w). While, non-spontaneous rusip is done by adding a culture mixture of Streptococcus, Leuconostoc, and Lactobacillus bacteria 2% (w/v). The materials are then incubated for 2 weeks. The data obtained were then performed t-test at the level of 5%. Spontaneous and non-spontaneous rusip fermentation process showed significant differences in total acid, reducing sugar, salt content, TVN, total lactic acid bacteria, total mold, and total microbial. The dominant amino acid content of spontaneous and non-spontaneous rusip are glutamic acid and aspartic acid, while the dominant fatty acids in spontaneous and non-spontaneous rusip are docosahexaenoic acid, palmitic acid, oleic acid, arachidonic acid, stearic acid, eicosapentaenoic acid, palmitoleic acid, and myristic acid.

Electron attachment and electron ionization of acetic acid clusters embedded in helium nanodroplets

NARCIS (Netherlands)

da Silva, F. Ferreira; Jaksch, S.; Martins, G.; Dang, H. M.; Dampc, M.; Denifl, S.; Maerk, T. D.; Limao-Vieira, P.; Liu, J.; Yang, S.; Ellis, A. M.; Scheier, P.

2009-01-01

The effect of incident electrons on acetic acid clusters is explored for the first time. The acetic acid clusters are formed inside liquid helium nanodroplets and both cationic and anionic products ejected into the gas phase are detected by mass spectrometry. The cation chemistry (induced by

The influence of roasting and baking on fatty acids composition of consumer oilseeds

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Natalia Mikołajczak

2017-09-01

Full Text Available Introduction and aim: Foods rich in nutrients have a positive effect on the human body. They are beneficial both for the health and the mind of human. Good sources of essential fatty acids and other biologically active compounds are oilseeds. It is important to include them in your daily diet. They can be added to dishes or serve as a snack. Brief description of the state of knowledge: The aim of this study was to evaluate of fatty acid composition in selected consumer oilseeds: sunflower, sesame, flax after application of typical technological processes such as roasting and baking, in different temperature, power and time ranges. In the research materials (before and after modification, the fatty acid composition was determined by gas chromatography. Summary: Based on obtained results, it was found that roasting and baking have an influence on the change in the content and composition of fatty acids. The strength of influence was dependent on the parameters (e.g. type of seed, temperature, time, power, which were used in the research. The roasting in the oven caused changes in the composition of saturated and unsaturated fatty acids, both in flax and sunflower seeds. The roasting in the microwave at 900 W affected on saturated fatty acids composition in flax seeds, similarly sunflower. In the case of sesame seeds, the influence of time on the content of mono- and polyunsaturated fatty acids was noted. The baking process caused significant changes in the fatty acid composition in the seeds from the crust of bread (flax seeds, sunflower seeds.

Nanodiamond composite as a material for cold electron emitters

Energy Technology Data Exchange (ETDEWEB)

Arkhipov, A V; Sominski, G G; Uvarov, A A [St.Petersburg State Polytechnic University, 29 Politchnicheskaya, St.Petersburg, 195251 (Russian Federation); Gordeev, S K; Korchagina, S B [FSUE ' Central Research Institute for Materials' , 8 Paradnaya Street, St.Petersburg, 191014 (Russian Federation)], E-mail: arkhipov@rphf.spbstu.ru

2008-03-15

Characteristics of field-induced electron emission were investigated for one of newly designed all-carbon materials - nanodiamond composite (NDC). The composite is comprised by 4-6 nm diamond grains covered with 0.2-1 nm-thick graphite-like shells that merge at grain junctions and determine such properties as mechanical strength and high electric conductivity. Large number of uniformly distributed sp{sup 3}-sp{sup 2} interfaces allowed to expect enhanced electron emission in electric field. Combination of these features makes NDC a promising material for cold electron emitters in various applications. Experimental testing confirmed high efficiency of electron emission from NDC. In comparison with previousely tested forms of nanocarbon, NDC emitters demonstrated better stabily and tolerance to performance conditions. Unusual activation scenarios and thermal dependencies of emission characteristics observed in experiments with NDC can add new background for explanation of facilitated electron emission from nanocarbons with relatively 'smooth' surface morphology.

Changes in cholesterol content and fatty acid composition of serum lipid in irradiated rat

International Nuclear Information System (INIS)

Ohashi, Shigeru

1979-01-01

The effect of a single dose of whole body irradiation on the serum cholesterol content and fatty acid composition of serum lipids in rats was investigated. A change in the fatty acid composition of liver lipids was also observed. After 600 rad of irradiation, the cholesterol content increased, reached a maximum 3 days after irradiation, and then decreased. After irradiation, an increase in cholesterol content and a marked decrease in triglyceride content were observed, bringing about a change in the amount of total serum lipids. The fatty acid compositions of normal and irradiated rat sera were compared. The relative percentages of palmitic and oleic acids in total lipids decreased while those of stearic and arachidonic acids increased. Serum triglyceride had trace amounts of arachidonic acid and the unsaturated fatty acid component decreased after irradiation. On the other hand, unsaturated fatty acid in cholesterol ester increased after irradiation, while linoleic and arachidonic acids made up 29% and 22% in the controls and 17% and 61% after irradiation, respectively. The fatty acid composition of total liver lipids after irradiation showed a decrease in palmitic and oleic acids and an increase in stearic and arachidonic acids, the same trend as observed in serum lipid fatty acid. Liver cholesterol ester showed trace amounts of linoleic and arachidonic acids and an increase in short-chain fatty acid after irradiation. The major component of serum phospholipids was phosphatidylcholine while palmitostearyl lecithine and unsaturated fatty acid were minor components. Moreover, phosphatidylcholine and phosphatidylethanolamine were the major components of liver phospholipids, having highly unsaturated fatty acids. The changes in fatty acid composition were similar to the changes in total phospholipids. (J.P.N.)

Fatty Acid Compositions of Six Wild Edible Mushroom Species

Science.gov (United States)

Günç Ergönül, Pelin; Akata, Ilgaz; Kalyoncu, Fatih; Ergönül, Bülent

2013-01-01

The fatty acids of six wild edible mushroom species (Boletus reticulatus, Flammulina velutipes var. velutipes, Lactarius salmonicolor, Pleurotus ostreatus, Polyporus squamosus, and Russula anthracina) collected from different regions from Anatolia were determined. The fatty acids were identified and quantified by gas chromatography and studied using fruit bodies. Fatty acid composition varied among species. The dominant fatty acid in fruit bodies of all mushrooms was cis-linoleic acid (18 : 2). Percentage of cis-linoleic acid in species varied from 22.39% to 65.29%. The other major fatty acids were, respectively, cis-oleic, palmitic, and stearic acids. Fatty acids analysis of the mushrooms showed that the unsaturated fatty acids were at higher concentrations than saturated fatty acids. PMID:23844377

Fatty Acid Compositions of Six Wild Edible Mushroom Species

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Pelin Günç Ergönül

2013-01-01

Full Text Available The fatty acids of six wild edible mushroom species (Boletus reticulatus, Flammulina velutipes var. velutipes, Lactarius salmonicolor, Pleurotus ostreatus, Polyporus squamosus, and Russula anthracina collected from different regions from Anatolia were determined. The fatty acids were identified and quantified by gas chromatography and studied using fruit bodies. Fatty acid composition varied among species. The dominant fatty acid in fruit bodies of all mushrooms was cis-linoleic acid (18 : 2. Percentage of cis-linoleic acid in species varied from 22.39% to 65.29%. The other major fatty acids were, respectively, cis-oleic, palmitic, and stearic acids. Fatty acids analysis of the mushrooms showed that the unsaturated fatty acids were at higher concentrations than saturated fatty acids.

Oil and fatty acid composition of peanut cultivars grown in Pakistan

International Nuclear Information System (INIS)

Hassan, F.; Ahmed, M.

2012-01-01

Quality and flavor of edible peanuts and its products are affected by fatty acid composition of oil. The information related to chemical composition of Peanut grown in the country are scarce, therefore, the present investigation was designed to determine the oil and fatty acid composition of some commonly grown peanut cultivars in Pakistan. Seven Peanut cultivars were grown during 2008 in randomized complete block design replicated thrice. The tested cultivars differed significantly for oil content which ranged from 49.83 to 53.06% on dry weight basis, thus showing differences of 7% among cultivars. The saturated fatty acids (Palmetic and Stearic acid) in different cultivars ranged between 9.95 to 10.79% and 1.63 to 2.19%, respectively. Differences among cultivars for oleic acid exhibited significance which ranged between 49.34 to 54.83%. Similarly, cultivars differed statistically for linoleic ac id which showed a range of 28.99 to 34.23%, thus depicted difference of 7%. Significant differences among tested cultivars may be attributed to the place of origin of particular cultivar. An inverse relationship was exhibited between oleic and linoleic acid, similar to other edible oils. (author)

Amino acid composition of casein isolated from the milks of different species

Energy Technology Data Exchange (ETDEWEB)

Lauer, B H; Baker, B E

1977-01-01

Casein was isolated from the milks of the following species: cow, horse, pig, reindeer, caribou, moose, harp seal, musk-ox, polar bear, dall sheep, and fin whale. The caseins were subjected to acid hydrolysis, the resultant amino acids were converted to their n-butyl-N-trifluoroacetyl esters, and the amino acid composition of the caseins was determined by gas chromatographic analysis of these esters. Notable among the results was the close similarity, with respect to amino acid composition, of reindeer and caribou caseins. The results of the amino acid analyses of the other caseins are presented and discussed.

Variation in oil content and fatty acid composition of sesame accessions from different origins

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C. Kurt

2018-03-01

Full Text Available Oil content and fatty acid composition are very important parameters for the human consumption of oilseed crops. Twenty-four sesame accessions including seven collected from various geographical regions of Turkey and 11 from different countries were investigated under field conditions for two consecutive years (2015 and 2016. The sesame accessions varied widely in their oil content and fatty acid compositions. The oil content varied between 44.6 and 53.1% with an average value of 48.15%. The content of oleic acids, linoleic acid, linolenic acid, palmitic acid,and stearic acid varied between 36.13–43.63%, 39.13–46.38%, 0.28–0.4%, 8.19–10.26%, and 4.63–6.35%, respectively. When total oil content and fatty acid composition were compared, Turkish sesame showed wide variation in oil and fatty acid compositions compared to those from other countries. However, the accessions from other countries were fewer compared to those from Turkey. It is essential to compare oil and fatty acid composition using a large number of germ plasm from different origins. In sesame oil, the average contents of oleic acid and linoleic acid were 39.02% and 43.64%, respectively, and their combined average content was 82.66%, representing the major fatty acid components in the oil from the sesame accessions used in the present study. The results obtained in this study provide useful information for the identification of better parents with high linoleic and oleic acid contents for developing elite sesame varieties with traits which are beneficial to consumer health.

Pseudo and true visible light photocatalytic activity of nanotube titanic acid/graphene composites

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiaodong, E-mail: donguser@hotmail.com; Liu, Xiaogang; Xue, Xiaoxiao; Pan, Hui; Zhang, Min; Li, Qiuye; Yu, Laigui; Yang, Jianjun; Zhang, Zhijun [Henan University, Key Laboratory of Ministry of Education for Special Functional Materials (China)

2013-09-15

Nanotube titanic acid/graphene (NTA/Gr) composites were prepared by an easy hydrothermal treatment of graphene oxide (GO) and NTA in a mixed solvent of ethanol-water. As-prepared NTA/Gr composites and GO were characterized by means of Fourier transform infrared spectrometry, X-ray diffraction, diffuse-reflection spectrometry, thermal analysis, and transmission electron microscopy. Besides, the photocatalytic activities of as-prepared NTA/Gr composites were evaluated by monitoring the degradation of methyl orange (MO) under visible light irradiation. It has been found that extending hydrothermal reaction time (24 h instead of 3 h) leads to great changes in the morphology and crystal structure of as-prepared composites. Namely, the orthorhombic NTA (ca. 10 nm in diameter) in the composite transformed to anatase TiO{sub 2} particle (ca. 20-30 nm in diameter) while the Gr sheets (with micrometers-long wrinkles) in it transformed to a few Gr fragments (ca. 50 nm in diameter). Correspondingly, the NTA/Gr composite transformed to titanium dioxide/graphene (TiO{sub 2}/Gr) composite. In the meantime, pure GO only has adsorption effect but it has no photocatalytic activity in the visible light region. Nevertheless, increasing Gr ratio results in enhanced visible light absorption capability and photocatalytic activity of NTA/Gr composites as well as the TiO{sub 2}/Gr composites. This demonstrates that the true visible light photocatalytic activity of NTA/Gr composites as well as the TiO{sub 2}/Gr composites for the degradation of MO is not as excellent as expected, and their high apparent activity is attributed to the strong adsorption of MO on the composites.

Pseudo and true visible light photocatalytic activity of nanotube titanic acid/graphene composites

Science.gov (United States)

Wang, Xiaodong; Liu, Xiaogang; Xue, Xiaoxiao; Pan, Hui; Zhang, Min; Li, Qiuye; Yu, Laigui; Yang, Jianjun; Zhang, Zhijun

2013-09-01

Nanotube titanic acid/graphene (NTA/Gr) composites were prepared by an easy hydrothermal treatment of graphene oxide (GO) and NTA in a mixed solvent of ethanol-water. As-prepared NTA/Gr composites and GO were characterized by means of Fourier transform infrared spectrometry, X-ray diffraction, diffuse-reflection spectrometry, thermal analysis, and transmission electron microscopy. Besides, the photocatalytic activities of as-prepared NTA/Gr composites were evaluated by monitoring the degradation of methyl orange (MO) under visible light irradiation. It has been found that extending hydrothermal reaction time (24 h instead of 3 h) leads to great changes in the morphology and crystal structure of as-prepared composites. Namely, the orthorhombic NTA (ca. 10 nm in diameter) in the composite transformed to anatase TiO2 particle (ca. 20-30 nm in diameter) while the Gr sheets (with micrometers-long wrinkles) in it transformed to a few Gr fragments (ca. 50 nm in diameter). Correspondingly, the NTA/Gr composite transformed to titanium dioxide/graphene (TiO2/Gr) composite. In the meantime, pure GO only has adsorption effect but it has no photocatalytic activity in the visible light region. Nevertheless, increasing Gr ratio results in enhanced visible light absorption capability and photocatalytic activity of NTA/Gr composites as well as the TiO2/Gr composites. This demonstrates that the true visible light photocatalytic activity of NTA/Gr composites as well as the TiO2/Gr composites for the degradation of MO is not as excellent as expected, and their high apparent activity is attributed to the strong adsorption of MO on the composites.

Bile acid composition of gallbladder contents in dogs with gallbladder mucocele and biliary sludge.

Science.gov (United States)

Kakimoto, Toshiaki; Kanemoto, Hideyuki; Fukushima, Kenjiro; Ohno, Koichi; Tsujimoto, Hajime

2017-02-01

OBJECTIVE To examine bile acid composition of gallbladder contents in dogs with gallbladder mucocele and biliary sludge. ANIMALS 18 dogs with gallbladder mucocele (GBM group), 8 dogs with immobile biliary sludge (i-BS group), 17 dogs with mobile biliary sludge (m-BS group), and 14 healthy dogs (control group). PROCEDURES Samples of gallbladder contents were obtained by use of percutaneous ultrasound-guided cholecystocentesis or during cholecystectomy or necropsy. Concentrations of 15 bile acids were determined by use of highperformance liquid chromatography, and a bile acid compositional ratio was calculated for each group. RESULTS Concentrations of most bile acids in the GBM group were significantly lower than those in the control and m-BS groups. Compositional ratio of taurodeoxycholic acid, which is 1 of 3 major bile acids in dogs, was significantly lower in the GBM and i-BS groups, compared with ratios for the control and m-BS groups. The compositional ratio of taurocholic acid was significantly higher and that of taurochenodeoxycholic acid significantly lower in the i-BS group than in the control group. CONCLUSIONS AND CLINICAL RELEVANCE In this study, concentrations and fractions of bile acids in gallbladder contents were significantly different in dogs with gallbladder mucocele or immobile biliary sludge, compared with results for healthy control dogs. Studies are needed to determine whether changes in bile acid composition are primary or secondary events of gallbladder abnormalities.

Fatty acids composition of Colonnata Lard from two different swine breeds

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P. Secchiari

2010-04-01

Full Text Available The study compares the fatty acid composition of the Colonnata lard obtained from two different swine breeds, Large White (LW and Cinta Senese (CS, during a one year long curing period. Samples of backfat were obtained from the carcass of three animals per breed and disposed into six different marble boxes according to the procedure of the disciplinary production of PGI “Lardo di Colonnata”. During curing period individual lard samples were collected monthly from each marble box. The fatty acid composition of pig backfat reflected the differences in the dietary regimen and in the rearing system of the two breeds. LW swine, in fact, were fed a commercial concentrate and reared in an intensive system, whereas CS swine were fed a diet composed by a commercial concentrate supplemented with acorn and reared in an outdoor system. Lard from LW contained higher amount of saturated fatty acids than lard from CS, whereas the content of unsaturated fatty acids (mainly monounsaturated fatty acids was lower. During the curing period the trend of lard fatty acids composition was different in the two breeds: the lard from CS seemed to be more susceptible to a faster hydrolysis of fatty acids than lard from LW, especially for the monounsaturated fatty acids, while the lard from LW seemed to be more susceptible to a faster hydrolysis of PUFA n-3.

Influence of conjugated linoleic acid (CLA on intramuscular fatty acid composition in rabbit

Directory of Open Access Journals (Sweden)

C. Corino

2010-01-01

Full Text Available The impact of feeding CLA has been thoroughly investigated in pigs, and Thiel- Cooper et al. (2001, Ostrowska et al. (2003, Lo Fiego et al. (2004, found that CLA modifies lipid fatty acid profile, negatively affecting some nutritional lipid indexes. So far,much less attention has been paid to rabbits. Recently, Corino et al. (2003 have shown that supplementing rabbit diets with CLA has limited effect on the chemical composition of meat and at a high slaughter weight reduces intramuscular fat content. The present research has been carried out to evaluate the effect of dietary CLA supplementation on cis-9, trans-11 and trans-10,cis-12- C18:2 isomers content, and on fatty acid composition of rabbit intramuscular lipids.

Fatty Acid Composition of Buffalo Milk Yellow Cheese after Technological Processing

International Nuclear Information System (INIS)

Ivanova, S.; Nacheva, I.; Miteva, D.

2010-01-01

The fatty acid composition of buffalo milk yellow cheese in fresh condition and after combining of two technological approaches – lyophilization and gamma sterilization with 1, 2 and 4 kGy, aiming at a prolongation of its shelf life, was investigated. The fat extraction from the milk samples was realized by the method of Roese-Gottlieb. The analysis of the fatty acids was made with the aid of gas chromatograph Shimadzu 2010. Minimal changes in the fatty acid composition of the buffalo milk yellow cheese after freeze-drying and gamma ray treatment were established

Fatty acid composition of buffalo milk yellow cheese after technological processing

International Nuclear Information System (INIS)

Ivanova, S.; Nacheva, I.; Miteva, D.

2010-01-01

The fatty acid composition of buffalo milk yellow cheese in fresh condition and after combining of two technological approaches – lyophilization and gamma sterilization with 1, 2 and 4 kGy, aiming at a prolongation of its shelf life, was investigated. The fat extraction from the milk samples was realized by the method of Roese-Gottlieb. The analysis of the fatty acids was made with the aid of gas chromatograph Shimadzu 2010. Minimal changes in the fatty acid composition of the buffalo milk yellow cheese after freeze-drying and gamma ray treatment were established

Effect of γ irradiation on the fatty acid composition of soybean and soybean oil.

Science.gov (United States)

Minami, Ikuko; Nakamura, Yoshimasa; Todoriki, Setsuko; Murata, Yoshiyuki

2012-01-01

Food irradiation is a form of food processing to extend the shelf life and reduce spoilage of food. We examined the effects of γ radiation on the fatty acid composition, lipid peroxidation level, and antioxidative activity of soybean and soybean oil which both contain a large amount of unsaturated fatty acids. Irradiation at 10 to 80 kGy under aerobic conditions did not markedly change the fatty acid composition of soybean. While 10-kGy irradiation did not markedly affect the fatty acid composition of soybean oil under either aerobic or anaerobic conditions, 40-kGy irradiation considerably altered the fatty acid composition of soybean oil under aerobic conditions, but not under anaerobic conditions. Moreover, 40-kGy irradiation produced a significant amount of trans fatty acids under aerobic conditions, but not under anaerobic conditions. Irradiating soybean oil induced lipid peroxidation and reduced the radical scavenging activity under aerobic conditions, but had no effect under anaerobic conditions. These results indicate that the fatty acid composition of soybean was not markedly affected by radiation at 10 kGy, and that anaerobic conditions reduced the degradation of soybean oil that occurred with high doses of γ radiation.

Carbon Nano tube Composites for Electronic Packaging Applications: A Review

International Nuclear Information System (INIS)

Aryasomayajula, L.; Wolter, K.J.

2013-01-01

Composite engineering comprises of metal matrix composites. They have high strength-weight ratio, better stiffness, economical production, and ease of availability of raw materials. The discovery of carbon nano tubes has opened new possibilities to face challenges better. Carbon Nano tubes are known for their high mechanical strength, excellent thermal and electrical properties. Recent research has made progress in fabricating carbon nano tube metal matrix and polymer-based composites. The methods of fabrication of these composites, their properties and possible applications restricted to the field of electronic packaging have been discussed in this paper. Experimental and theoretical calculations have shown improved mechanical and physical properties like tensile stress, toughness, and improved electrical and thermal properties. They have also demonstrated the ease of production of the composites and their adaptability as one can tailor their properties as per the requirement. This paper reviews work reported on fabricating and characterizing carbon- nano tube-based metal matrix and polymer composites. The focus of this paper is mainly to review the importance of these composites in the field of electronics packaging.

Protein and Amino Acid Composition of Water Melon ( Citrullus ...

African Journals Online (AJOL)

The protein and amino acids composition of seeds and pulp of watermelon, Citrullus lanatus were analyzed using Kjeldahl method and ion-exchange chromatography (IEC) respectively. The protein contents (% dry matter) of seeds and pulp were found to be 24.23 and 1.05% respectively. The results of amino acids ...

Proximate composition and amino acid profile of rice husk ...

African Journals Online (AJOL)

Native rice husk (NRH) was fermented with Pleurotus ostreatus for 7, 14 and 21 days to improve the nutritional values. The proximate composition and amino acid profiles were determined. The results showed that crude fibre (CF), nitrogen free extract (NFE), acid detergent fibre (ADF), and neutral detergent fibre (NDF) were ...

Development of a wood-polymer composite by electron beam hardening

International Nuclear Information System (INIS)

Gotoda, Masao

1974-01-01

An incombustible wood-polymer composite (WPC) was studied. The dimensional stability was also tested. The comparison of conversion ratio was made between gamma-ray and electron beam and between a vinylidene chloride 100% impregnated beech composite and bulk. In the case of gamma-ray of low dose rate, the conversion ratio in the vinylidene chloride beech composite was lower than the bulk. In the case of electron beam, though dose rate was higher than that of gamma-ray, the conversion ratio was low, and was influenced by the moisture content of wood. The conversion ratio markedly decreased with the increase of the dose rate of electron beam. Roughly 50% polymer loading can be obtained when the dose rate of electron beam is low. In the case of gamma-ray, the effect of dimensional stability was approximately none with small polymer loading, whereas in the case of electron beam irradiation of moist wood, marked effect of dimensional stability was shown. Incombustibility effect was tested by burning a 150 mm long piece, in which three small pieces of 5 x 10 x 50 mm were connected with epoxy resin adhesive, with a Bunsen burner for 30 seconds. After the completion of burning, the long piece was separated back into three small pieces, and the char length, weight loss and after glow time were tested. The beech composite was expected to become incombustible at 40% polymer loading. The vinyl monomer solution of chlorinated aryl chloride oligomer can be easily hardened by electron beam irradiation. Addition of crosslinking agent such as trimethylol propane trimethracrylate prevents the dissolution of hardened methyl acrylate and methyl methacrylate by acetone. The electron beam hardening of aryl resin compound is possible, using benzen peroxide as a catalyst. Floor material can be produced by this process from low density, low price wood. (Iwakiri, K.)

Study on the change of total fat content and fatty acid composition of the ethanol extract from cooking drips of thunnus thynnus by ionizing irradiation

Energy Technology Data Exchange (ETDEWEB)

Lee, Hee Sub; Choi, Jong Il; Kim, Hyun Joo; Kim, Jin Kyu; Byun, Myung Woo; Lee, Ju Woon [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Yoo, Cheon Woo; Kim, Ju Bong [Dongwon Research and Development Center, Seongnam (Korea, Republic of); Hwang, Young Jung [Division of Food Science, Jinju International University, Jinju (Korea, Republic of); Chung, Young Jin [Dept. of Food and Nutrition, Chungnam National University, Daejeon (Korea, Republic of)

2008-05-15

This study was conducted to examine the effect of a gamma irradiation (GM) and an electron-beam irradiation (EB) on the total fat content and fatty acid composition of ethanol extract from cooking drips of Thunnus thynnus (ECT). The total fat content of samples were determined by fat extraction (Folch method) and fatty acid composition was by gas chromatography mass spectrometry (GC-MS) after fat extraction. The results showed that total fat contents were not changed by GM and EB up to the dose of 50 kGy. The content of unsaturated fatty acids (USFA) such as vaccenic acid and DHA, was decreased by irradiation. But, the content of palmitoleic acid was not changed by GM. In contrast, the content of saturated fatty acids(SFA) such as myristic acid and palmitic acid, was increased by the irradiation. But, the content of stearic acid was decreased with the increase of irradiation dose. Also, it has been shown that the GM had further affected the change of fatty acid content than EB.

Study on the change of total fat content and fatty acid composition of the ethanol extract from cooking drips of thunnus thynnus by ionizing irradiation

International Nuclear Information System (INIS)

Lee, Hee Sub; Choi, Jong Il; Kim, Hyun Joo; Kim, Jin Kyu; Byun, Myung Woo; Lee, Ju Woon; Yoo, Cheon Woo; Kim, Ju Bong; Hwang, Young Jung; Chung, Young Jin

2008-01-01

This study was conducted to examine the effect of a gamma irradiation (GM) and an electron-beam irradiation (EB) on the total fat content and fatty acid composition of ethanol extract from cooking drips of Thunnus thynnus (ECT). The total fat content of samples were determined by fat extraction (Folch method) and fatty acid composition was by gas chromatography mass spectrometry (GC-MS) after fat extraction. The results showed that total fat contents were not changed by GM and EB up to the dose of 50 kGy. The content of unsaturated fatty acids (USFA) such as vaccenic acid and DHA, was decreased by irradiation. But, the content of palmitoleic acid was not changed by GM. In contrast, the content of saturated fatty acids(SFA) such as myristic acid and palmitic acid, was increased by the irradiation. But, the content of stearic acid was decreased with the increase of irradiation dose. Also, it has been shown that the GM had further affected the change of fatty acid content than EB

Soil amino acid composition across a boreal forest successional sequence

Science.gov (United States)

Nancy R. Werdin-Pfisterer; Knut Kielland; Richard D. Boone

2009-01-01

Soil amino acids are important sources of organic nitrogen for plant nutrition, yet few studies have examined which amino acids are most prevalent in the soil. In this study, we examined the composition, concentration, and seasonal patterns of soil amino acids across a primary successional sequence encompassing a natural gradient of plant productivity and soil...

Influence of a peracetic acid-based immersion on indirect composite resin.

Science.gov (United States)

Samuel, Susana Maria Werner; Fracaro, Gisele Baggio; Collares, Fabrício Mezzomo; Leitune, Vicente Castelo Branco; Campregher, Ulisses Bastos

2011-06-01

The aim of this study was to evaluate the influence of immersion in a 0.2% peracetic acid-based disinfectant on the three-point flexural strength, water sorption and water solubility of an indirect composite resin. Specimens were produced according to ISO 4049:2000 specifications and were divided in two groups: Control group, with no disinfection and Disinfected group, with three 10 min immersions in the peracetic acid intercalated with 10 min immersions in sterile distilled water. All evaluations were conducted in compliance with ISO specifications. Three-point flexural strength, water sorption and solubility of indirect composite resin before and after immersion showed no statistical significant differences (p > 0.05) and met ISO standard requirements. Immersion in peracetic acid solution showed no influence in indirect composite resin tested properties.

The influence of hen age on fatty acid composition of commercial eggs

Directory of Open Access Journals (Sweden)

Tina Lešić

2017-01-01

Full Text Available The aim of this study was to investigate the nutritional composition of commercial eggs from Lohman Brown hens through fat and fatty acid content analysis, as well as to evaluate the effect of hen age on the above parameters. Egg samples (n=108 were collected every two weeks from 21- to 55- week old hens during the 2015/2016 autumn/winter period. The results revealed significant differences in fatty acid composition dependent on hen age (p 0.05. The total polyunsaturated fatty acid (PUFA content was statistically significantly higher in eggs laid by 55- week old hens as compared to those laid by 21- week old hens. The n-6/n-3 and PUFA/SFA ratios were more favourable in the elder hens. In general, the results revealed hen ageing-based variations in fatty acid composition of their eggs, in particular in the representation of linoleic (LA, alpha-linolenic (ALA and arachidonic acid (AA, for which statistically significant hen age-based differences were found.

Reactivity of H atoms and hydrated electrons with chlorobenzoic acids

Energy Technology Data Exchange (ETDEWEB)

Zona, Robert [Department of Nutritional Sciences, Section Radiation Biology, University of Vienna, UZAII, Althanstrasse 14, A-1090 Vienna (Austria); Solar, Sonja [Department of Nutritional Sciences, Section Radiation Biology, University of Vienna, UZAII, Althanstrasse 14, A-1090 Vienna (Austria)], E-mail: sonja.solar@univie.ac.at; Getoff, Nikola [Department of Nutritional Sciences, Section Radiation Biology, University of Vienna, UZAII, Althanstrasse 14, A-1090 Vienna (Austria); Sehested, Knud; Holcman, Jerzy [Environmental Science and Technology Department, RISO National Laboratory, DK-4000, Roskilde (Denmark)

2008-02-15

H radicals react with chlorobenzoic acids and chlorobenzene (k(H{sup {center_dot}}+substrates)=(0.7-1.5)x10{sup 9} dm{sup 3} mol{sup -1} s{sup -1}) by addition to the benzene ring forming H adducts with characteristic absorption bands in the range of 310-360 nm. The rate constants for their second-order decay are 2k=(3.5-6)x10{sup 8} dm{sup 3} mol{sup -1} s{sup -1}. By reduction with e{sub aq}{sup -} fragmentation and chloride release was established for 2- and 4-chlorobenzoic acid, for 3-chlorobenzoic acid the addition of electrons to the carboxylate group was observed by pulse radiolysis. By gamma radiolysis could be proved that these radical anions undergo intramolecular electron transfer and quantitave dechlorination. The efficiency in degradation was 4-chlorobenzoic acid>3-chlorobenzoic acid>2-chlorobenzoic acid. Benzoic acid was found as final product for all substrates.

Impact of region on the composition of milk fatty acids in China.

Science.gov (United States)

Yang, Yongxin; Wang, Jiaqi; Yuan, Tingjie; Bu, Dengpan; Yang, Jinhui; Zhou, Lingyun; Sun, Peng; Zhang, Juanxia

2013-08-30

Milk composition and its fatty acid profile have received much attention with respect to improving human health. However, limited work has been conducted to assess the composition of milk fat in China, which is the third largest producer of milk in the world. In this study the effects of geographical region and seasonal changes (spring and summer) on the fatty acid composition of milk samples collected from six Chinese farms were investigated. Milk fat and protein contents, as well as some individual fatty acids and five fatty acid groups, were found to be unaffected by season, but they did show significant differences by geographical region. Levels of milk cis-9, trans-11 conjugated linoleic acid decreased in summer and increased in spring, increased in north (Hohhot), northeast (Harbin), north centre (Beijing) and northwest (Xi'an) China and decreased in far northwest (Urumqi) and east (Chuzhou) China. Monounsaturated fatty acids increased in east and northwest China and decreased in northeast China, while polyunsaturated fatty acids increased in far northwest and north centre China and decreased in northeast China. This study provides relevent information that contributes to the understanding of parameters affecting variability of milk fatty acid profiles. © 2012 Society of Chemical Industry.

Brain and liver fatty acid composition changes upon consumption of Lactobacillus rhamnosus LA68.

Science.gov (United States)

Ivanovic, Nevena; Minic, Rajna; Djuricic, Ivana; Dimitrijevic, Ljiljana; Sobajic, Sladjana; Zivkovic, Irena; Djordjevic, Brizita

2015-02-01

Recent reports suggest that the metabolic activity of the enteric microbiota may influence the fatty acid composition of the host tissue. There are many studies dealing with the influence of lactobacilli on various pathological conditions, and some of the effects are strain-specific. This study was designed to test the effects of a particular Lactobacillus strain, Lactobacillus rhamnosus LA68 on fatty acid composition of the liver and the brain of C57BL/6 mice in the absence of an underlying pathological condition. Female mice were supplemented with live L. rhamnosus LA68 bacteria for the duration of 1 month. Serum biochemistry was analyzed and liver and brain fatty acid composition was assessed by gas-liquid chromatography. Significant changes in liver and brain fatty acid composition were detected. In the liver tissue we detected an increase in palmitoleic acid (p = 0.038), while in the brain compartment we found an increase in palmitic (p = 0.042), stearic (p = 0.017), arachidonic acid (p = 0.009) and docosahexaenoic acid (p = 0.004) for control versus experimental group. These results show discrete changes caused by LA68 strain consumption. Even short duration of administration of LA68 influences the fatty acid composition of the host which adds to the existing knowledge about Lactobacillus host interaction, and adds to the growing knowledge of metabolic intervention possibilities.

Membrane fatty acid composition and radiation response of Bp8 sarcoma ascites tumour cells

International Nuclear Information System (INIS)

Harms-Ringdahl, M.

1987-01-01

Radiation responses of Bp8 sarcoma ascites tumour cells with differences in membrane fatty acid composition was studied. The cells were grown i.p. in NMRI mice and their membrane composition was changed in response to different dietary regimes provided to the hosts. Cell survival, varied insignificantly between the four dietary groups, while repair capacity differed significantly. Increased repair capacity was observed for ascites cells grown in animals on diets enriched in sunflower seed oil and coconut oil, compared with cells from mice fed the hydrogenated lard diet or from cells from the control animals. The membrane fatty acid composition of the cells from the two dietary groups with increased levels of repair capacity differed extensively, and in general there was no correlation between radiation response and the membrane fatty acid composition of the four groups. For coconut oil and control groups with marked differences in membrane fatty acid composition, the effects of irradiation on ascites tumour growth rate and cell cycle distribution were followed in vivo. For none of the parameters was an effect on membrane fatty acid composition on radiation response observed. (author)

Effect of dietary fatty acids on the postprandial fatty acid composition of triacylglycerol-rich lipoproteins in healthy male subjects

DEFF Research Database (Denmark)

Bysted, Anette; Holmer, G.; Lund, Pia

2005-01-01

interesterified test fats with equal amounts of palmitic acid ( P fat), stearic acid (S fat), trans-18: 1 isomers (T fat), oleic acid (O fat), or linoleic acid (L fat) were tested. Subjects: A total of 16 healthy, normolipidaemic males ( age 23 +/- 2 y) were recruited. Interventions: The participants ingested fat......Objective: The aim of the present study was to investigate the effect of trans-18: 1 isomers compared to other fatty acids, especially saturates, on the postprandial fatty acid composition of triacylglycerols ( TAG) in chylomicrons and VLDL. Design: A randomised crossover experiment where five......-rich test meals ( 1 g fat per kg body weight) and the fatty acid profiles of chylomicron and VLDL TAG were followed for 8 h. Results: The postprandial fatty acid composition of chylomicron TAG resembled that of the ingested fats. The fatty acids in chylomicron TAG were randomly distributed among the three...

New Polylactic Acid Composites Reinforced with Artichoke Fibers

OpenAIRE

Botta, Luigi; Fiore, Vincenzo; Scalici, Tommaso; Valenza, Antonino;  , Roberto

2015-01-01

In this work, artichoke fibers were used for the first time to prepare poly(lactic acid) (PLA)-based biocomposites. In particular, two PLA/artichoke composites with the same fiber loading (10% w/w) were prepared by the film-stacking method: the first one (UNID) reinforced with unidirectional long artichoke fibers, the second one (RANDOM) reinforced by randomly-oriented long artichoke fibers. Both composites were mechanically characterized in tensile mode by quasi-static and dynamic mechanica...

Fungicidal PMMA-Undecylenic Acid Composites

Directory of Open Access Journals (Sweden)

Milica Petrović

2018-01-01

Full Text Available Undecylenic acid (UA, known as antifungal agent, still cannot be used to efficiently modify commercial dental materials in such a way that this affects Candida. Actually, issues with Candida infections and fungal resistance compromise the use of Poly(methyl-methacrylate (PMMA as dental material. The challenge remains to turn PMMA into an antifugal material, which can ideally affect both sessile (attached and planktonic (free-floating Candida cells. We aimed to tackle this challenge by designing PMMA-UA composites with different UA concentrations (3–12%. We studied their physico-chemical properties, the antifungal effect on Candida and the cytotoxicity toward human cells. We found that UA changes the PMMA surface into a more hydrophilic one. Mainly, as-preparation composites with ≥6% UA reduced sessile Candida for >90%. After six days, the composites were still efficiently reducing the sessile Candida cells (for ~70% for composites with ≥6% UA. Similar results were recorded for planktonic Candida. Moreover, the inhibition zone increased along with the UA concentration. The antifungal effect of UA was also examined at the surface of an UA-loaded agar and the minimal inhibitory concentration (MIC90 was below the lowest-studied 0.0125% UA. Furthermore, the embedded filamentation test after 24 h and 48 h showed complete inhibition of the Candida growth at 0.4% UA.

Fungicidal PMMA-Undecylenic Acid Composites.

Science.gov (United States)

Petrović, Milica; Bonvin, Debora; Hofmann, Heinrich; Mionić Ebersold, Marijana

2018-01-08

Undecylenic acid (UA), known as antifungal agent, still cannot be used to efficiently modify commercial dental materials in such a way that this affects Candida . Actually, issues with Candida infections and fungal resistance compromise the use of Poly(methyl-methacrylate) (PMMA) as dental material. The challenge remains to turn PMMA into an antifugal material, which can ideally affect both sessile (attached) and planktonic (free-floating) Candida cells. We aimed to tackle this challenge by designing PMMA-UA composites with different UA concentrations (3-12%). We studied their physico-chemical properties, the antifungal effect on Candida and the cytotoxicity toward human cells. We found that UA changes the PMMA surface into a more hydrophilic one. Mainly, as-preparation composites with ≥6% UA reduced sessile Candida for >90%. After six days, the composites were still efficiently reducing the sessile Candida cells (for ~70% for composites with ≥6% UA). Similar results were recorded for planktonic Candida . Moreover, the inhibition zone increased along with the UA concentration. The antifungal effect of UA was also examined at the surface of an UA-loaded agar and the minimal inhibitory concentration (MIC90) was below the lowest-studied 0.0125% UA. Furthermore, the embedded filamentation test after 24 h and 48 h showed complete inhibition of the Candida growth at 0.4% UA.

Fungicidal PMMA-Undecylenic Acid Composites

Science.gov (United States)

Petrović, Milica; Hofmann, Heinrich

2018-01-01

Undecylenic acid (UA), known as antifungal agent, still cannot be used to efficiently modify commercial dental materials in such a way that this affects Candida. Actually, issues with Candida infections and fungal resistance compromise the use of Poly(methyl-methacrylate) (PMMA) as dental material. The challenge remains to turn PMMA into an antifugal material, which can ideally affect both sessile (attached) and planktonic (free-floating) Candida cells. We aimed to tackle this challenge by designing PMMA-UA composites with different UA concentrations (3–12%). We studied their physico-chemical properties, the antifungal effect on Candida and the cytotoxicity toward human cells. We found that UA changes the PMMA surface into a more hydrophilic one. Mainly, as-preparation composites with ≥6% UA reduced sessile Candida for >90%. After six days, the composites were still efficiently reducing the sessile Candida cells (for ~70% for composites with ≥6% UA). Similar results were recorded for planktonic Candida. Moreover, the inhibition zone increased along with the UA concentration. The antifungal effect of UA was also examined at the surface of an UA-loaded agar and the minimal inhibitory concentration (MIC90) was below the lowest-studied 0.0125% UA. Furthermore, the embedded filamentation test after 24 h and 48 h showed complete inhibition of the Candida growth at 0.4% UA. PMID:29316713

Access Control Model for Sharing Composite Electronic Health Records

Science.gov (United States)

Jin, Jing; Ahn, Gail-Joon; Covington, Michael J.; Zhang, Xinwen

The adoption of electronically formatted medical records, so called Electronic Health Records (EHRs), has become extremely important in healthcare systems to enable the exchange of medical information among stakeholders. An EHR generally consists of data with different types and sensitivity degrees which must be selectively shared based on the need-to-know principle. Security mechanisms are required to guarantee that only authorized users have access to specific portions of such critical record for legitimate purposes. In this paper, we propose a novel approach for modelling access control scheme for composite EHRs. Our model formulates the semantics and structural composition of an EHR document, from which we introduce a notion of authorized zones of the composite EHR at different granularity levels, taking into consideration of several important criteria such as data types, intended purposes and information sensitivities.

Thermophysical properties of starch and whey protein composite prepared in presence of organic acid and esters

Science.gov (United States)

Previously, we prepared starch and protein composite by reactive mixing in presence of various organic acids and found that use of these acid esters resulted in composites with good mechanical properties. In this study, concentration (% w/w) of acid citrates in the starch-protein composites were var...

Amino acid composition in parenteral nutrition: what is the evidence?

Science.gov (United States)

Yarandi, Shadi S.; Zhao, Vivian M.; Hebbar, Gautam; Ziegler, Thomas R.

2011-01-01

Purpose of review Complete parenteral nutrition solutions contain mixed amino acid products providing all nine essential amino acids and a varying composition of nonessential amino acids. Relatively little rigorous comparative efficacy research on altered parenteral nutrition amino acid composition has been published in recent years. Recent findings Limited data from randomized, double-blind, adequately powered clinical trials to define optimal doses of total or individual amino acids in parenteral nutrition are available. An exception is the growing number of studies on the efficacy of glutamine supplementation of parenteral nutrition or given as a single parenteral agent. Parenteral glutamine appears to confer benefit in selected patients; however, additional data to define optimal glutamine dosing and the patient subgroups who may most benefit from this amino acid are needed. Although some promising studies have been published, little data are available in the current era of nutrition support on the clinical efficacy of altered doses of arginine, branched chain amino acids, cysteine, or taurine supplementation of parenteral nutrition. Summary Despite routine use of parenteral nutrition, surprisingly little clinical efficacy data are available to guide total or specific amino acid dosing in adult and pediatric patients requiring this therapy. This warrants increased attention by the research community and funding agencies to better define optimal amino acid administration strategies in patient subgroups requiring parenteral nutrition. PMID:21076291

Variation of lipid and fatty acid compositions in Thai Perilla seeds grown at different locations

Directory of Open Access Journals (Sweden)

Maitree Suttajit

2006-03-01

Full Text Available Perilla or Nga-Kee-Mon (Perilla frutescens seed has long been known as a rich source of α-linolenic acid (18:3, n-3. It is widely cultivated throughout Thailand. However, there are no data on the variation of lipid and fatty acid compositions among crops from different regions. The aim of this study was to examine the compositions of lipids and fatty acids in Thai perilla seed grown at different locations. Two different perilla seeds were harvested from Maehongsorn and Chiang Mai districts, and one commercial perilla was purchased from local market. Seeds were ground, lipid was extracted with chloroform: methanol (2:1, v/v and its composition determined by Iatroscan (TLC/FID. Fatty acid composition was analyzed with GLC using standard methods. Lipid content was between 34-36% (w/w. Triacylglycerol was a predominant lipid in perilla seed (97% of total lipids, and a minor component was phytosterol (3% of total lipids. The ratio of saturates: monounsaturates: polyunsaturates was approximately 1: 1: 8. Most predominant fatty acid was α-linolenic acid (18:3, n-3 (55-60% of total fatty acid. Seeds from Maehongsorn district had the highest concentration of α-linolenic acid, and commercial perilla had the lowest (P<0.05. Other two predominant fatty acids were linoleic acid (18:2, n-6 (18-22% of total fatty acid and oleic acid (18:1 (11-13% of total fatty acid. The results showed that the compositions of lipids and fatty acids in Thai perilla seeds varied significantly among samples from different locations.

Electron-induced chemistry in microhydrated sulfuric acid clusters

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J. Lengyel

2017-11-01

Full Text Available We investigate the mixed sulfuric acid–water clusters in a molecular beam experiment with electron attachment and negative ion mass spectrometry and complement the experiment by density functional theory (DFT calculations. The microhydration of (H2SO4m(H2On clusters is controlled by the expansion conditions, and the electron attachment yields the main cluster ion series (H2SO4m(H2OnHSO4− and (H2OnH2SO4−. The mass spectra provide an experimental evidence for the onset of the ionic dissociation of sulfuric acid and ion-pair (HSO4−  ⋅  ⋅  ⋅  H3O+ formation in the neutral H2SO4(H2On clusters with n ≥ 5 water molecules, in excellent agreement with the theoretical predictions. In the clusters with two sulfuric acid molecules (H2SO42(H2On this process starts as early as n ≥ 2 water molecules. The (H2SO4m(H2OnHSO4− clusters are formed after the dissociative electron attachment to the clusters containing the (HSO4−  ⋅  ⋅  ⋅  H3O+ ion-pair structure, which leads to the electron recombination with the H3O+ moiety generating H2O molecule and the H-atom dissociation from the cluster. The (H2OnH2SO4− cluster ions point to an efficient caging of the H atom by the surrounding water molecules. The electron-energy dependencies exhibit an efficient electron attachment at low electron energies below 3 eV, and no resonances above this energy, for all the measured mass peaks. This shows that in the atmospheric chemistry only the low-energy electrons can be efficiently captured by the sulfuric acid–water clusters and converted into the negative ions. Possible atmospheric consequences of the acidic dissociation in the clusters and the electron attachment to the sulfuric acid–water aerosols are discussed.

Disposal Options of Bamboo Fabric-Reinforced Poly(Lactic Acid Composites for Sustainable Packaging: Biodegradability and Recyclability

Directory of Open Access Journals (Sweden)

M.R. Nurul Fazita

2015-08-01

Full Text Available The present study was conducted to determine the recyclability and biodegradability of bamboo fabric-reinforced poly(lactic acid (BF-PLA composites for sustainable packaging. BF-PLA composite was recycled through the granulation, extrusion, pelletization and injection processes. Subsequently, mechanical properties (tensile, flexural and impact strength, thermal stability and the morphological appearance of recycled BF-PLA composites were determined and compared to BF-PLA composite (initial materials and virgin PLA. It was observed that the BF-PLA composites had the adequate mechanical rigidity and thermal stability to be recycled and reused. Moreover, the biodegradability of BF-PLA composite was evaluated in controlled and real composting conditions, and the rate of biodegradability of BF-PLA composites was compared to the virgin PLA. Morphological and thermal characteristics of the biodegradable BF-PLA and virgin PLA were obtained by using environment scanning electron microscopy (ESEM and differential scanning calorimetry (DSC, respectively. The first order decay rate was found to be 0.0278 and 0.0151 day−1 in a controlled composting condition and 0.0008 and 0.0009 day−1 in real composting conditions for virgin PLA and BF-PLA composite, respectively. Results indicate that the reinforcement of bamboo fabric in PLA matrix minimizes the degradation rate of BF-PLA composite. Thus, BF-PLA composite has the potential to be used in product packaging for providing sustainable packaging.

Effects of radiation-induced crosslinking on thermal and mechanical properties of poly(lactic acid) composites reinforced by basalt fiber

International Nuclear Information System (INIS)

Liu Meihua; Zhang Wanxi; Yin Yuan; Wei Wei; Zheng Chunbai; Deng Pengyang; Shen Shirley

2013-01-01

Poly (lactic acid)/ basalt fiber (PLA/BF) composites were prepared by melt blending with a cross-linking agent, triallyl isocyanurate (TAIC). The thermal and mechanical properties of the composites were investigated through gel fraction, heat defection temperature (HDT), tensile tests and scanning electron microscopy (SEM). Under certain conditions, the HDT of composites was dramatically increased to 140℃ after irradiation. Tensile properties were enhanced as well. Both these improvements were consistent with changes of the fracture morphology. Compatibilization and concomitant enhancement of the interfacial adhesive between the polymer matrix and the inorganic fiber were achieved as seen from SEM photos, as a result of the formation of co-crosslinking and grafting structures at the interface according to the determination of gelation extraction. (authors)

Milk fat globules: fatty acid composition, size and in vivo regulation of fat liquidity.

Science.gov (United States)

Timmen, H; Patton, S

1988-07-01

Populations of large and small milk fat globules were isolated and analyzed to determine differences in fatty acid composition. Globule samples were obtained by centrifugation from milks of a herd and of individual animals produced under both pasture and barn feeding. Triacylglycerols of total globule lipids were prepared by thin layer chromatography and analyzed for fatty acid composition by gas chromatography. Using content of the acids in large globules as 100%, small globules contained fewer short-chain acids, -5.9%, less stearic acid, -22.7%, and more oleic acids, +4.6%, mean values for five trials. These differences are consistent with alternative use of short-chain acids or oleic acid converted from stearic acid to maintain liquidity at body temperature of milk fat globules and their precursors, intracellular lipid droplets. Stearyl-CoA desaturase (EC 1.14.99.5), which maintains fluidity of cellular endoplasmic reticulum membrane, is suggested to play a key role in regulating globule fat liquidity. Possible origins of differences between individual globules in fatty acid composition of their triacylglycerols are discussed.

Amino acid composition of protein-enriched dried pasta

OpenAIRE

Vidrih, Rajko; Filip, Sebastjan

2016-01-01

Today, obesity is one of the major health problems, a so-called epidemic of the developed world. Obesity arises through an imbalance between energy intake and energy expenditure, so it is important for products to have a balanced nutritional composition. The aim of this study is to prepare high-protein pasta with high nutritional quality, with emphasis on its amino acid composition, as ordinary durum pasta lacks lysine and threonine. Ordinary durum wheat pasta contains, on average, 77 % carbo...

Proton conductivity of phosphoric acid doped polybenzimidazole and its composites with inorganic proton conductors

DEFF Research Database (Denmark)

He, Ronghuan; Qingfeng, Li; Gang, Xiao

2003-01-01

Phosphoric acid doped polybenzimidazole (PBI) and PBI composite membranes have been prepared in the present work. The PBI composites contain inorganic proton conductors including zirconium phosphate (ZrP), (Zr(HPO4)2·nH2O), phosphotungstic acid (PWA), (H3PW12O40·nH2O) and silicotungstic acid (Si...

Animal factors affecting fatty acid composition of cow milk fat: A review

African Journals Online (AJOL)

, cow individuality, parity and stage of lactation) on fatty acid (FA) composition of milk fat. Genetic parameters affecting the composition of the FAs in milk are reviewed and the possibilities for altering milk fat composition are discussed.

Amino acid composition in determination of collagen origin and assessment of physical factors effects.

Science.gov (United States)

Gauza-Włodarczyk, Marlena; Kubisz, Leszek; Włodarczyk, Dariusz

2017-11-01

The amino acid composition of collagen is a characteristic feature of this protein. Collagen, irrespective of its origin, contains 19 amino acids, including hydroxyproline which does not occur in other proteins. Its atypical amino acid composition is characterized by high content of proline and glycine, as well as the absence of cysteine. This paper shows the comparison of qualitative composition of amino acids of fish skin (FS) collagen, bovine Achilles tendon (BAT) collagen, and bone collagen. Results demonstrate that FS collagen as well as BAT collagen contains no cysteine and significantly different amount of hydroxyproline. In BAT collagen hydroxyproline content is 30% higher than hydroxyproline content of FS collagen. In bone collagen the amount of hydroxyproline is two times more than in FS collagen. Furthermore, it is shown that sensitivity to radiation of individual amino acids varies and depends on the absorbed dose of ionizing radiation. The changes observed in the amino acid composition become very intense for the doses of 500kGy and 1000kGy. Copyright © 2017 Elsevier B.V. All rights reserved.

Electron-beam-induced post-grafting polymerization of acrylic acid onto the surface of Kevlar fibers

Science.gov (United States)

Xu, Lu; Hu, Jiangtao; Ma, Hongjuan; Wu, Guozhong

2018-04-01

The surface of Kevlar fibers was successfully modified by electron beam (EB)-induced post-grafting of acrylic acid (AA). The generation of radicals in the fibers was confirmed by electron spin resonance (ESR) measurements, and the concentration of radicals was shown to increase as the absorbed dose increased, but decrease with increasing temperature. The influence of the synthesis conditions on the degree of grafting was also investigated. The surface microstructure and chemical composition of the modified Kevlar fibers were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The SEM images revealed that the surface of the grafted fibers was rougher than those of the pristine and irradiated fibers. XPS analysis confirmed an increase in C(O)OH groups on the surface of the Kevlar fibers, suggesting successful grafting of AA. These results indicate that EB-induced post-grafting polymerization is effective for modifying the surface properties of Kevlar fibers.

Chemical Composition and Fatty Acids of Glodok Fish by High Thermal Processing

Directory of Open Access Journals (Sweden)

Sri Purwaningsih

2014-11-01

Full Text Available Glodok is an economically underrated fish with a high nutrient content. The research aims to study the changes on chemical composition, fatty acids, omega-6 and omega-3 ratio in glodok muscle after processing with different methods of boiling, steaming, and boiling with addition of salt (3%. The results showed that the treatment (boiling, steaming, and boiling with addition of salt gives a significant effect (α=0.05 in water content, ash, lipid content, nervonat acid, linoleic acid, arachidonic acid, EPA, and DHA. The best processing method was steaming. The ratio of omega-3 and omega-6 in fresh glodok fish was 2,1:1, which is higher than WHO recommendation of 0,6:1,7.Keywords: chemical composition, fatty acid, glodok fish, processing

Starch/fiber/poly(lactic acid) foam and compressed foam composites

Science.gov (United States)

Composites of starch, fiber, and poly(lactic acid) (PLA) were made using a foam substrate formed by dehydrating starch or starch/fiber gels. PLA was infiltrated into the dry foam to provide better moisture resistance. Foam composites were compressed into plastics using force ranging from 4-76MPa. Te...

Composite electrolytes composed of Cs-substituted phosphotungstic acid and sulfonated poly(ether-ether ketone) for fuel cell systems

Energy Technology Data Exchange (ETDEWEB)

Oh, Song-Yul, E-mail: ms089203@tutms.tut.ac.jp [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan); Yoshida, Toshihiro; Kawamura, Go [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan); Muto, Hiroyuki [Department of Materials Science and Engineering, Kurume National College of Technology, 1-1-1 Komorino, Kurume, Fukuoka 830-8555 (Japan); Sakai, Mototsugu [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan); Matsuda, Atsunori, E-mail: matsuda@tutms.tut.ac.jp [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan)

2010-10-15

Composite electrolytes composed of cesium hydrogen sulfate containing phosphotungstic acids (CsHSO{sub 4}-H{sub 3}PW{sub 12}O{sub 40}) and sulfonated poly(ether-ether ketone) (SPEEK) were prepared by casting the corresponding precursor for application in fuel cells. Partially Cs-substituted phosphotungstic acids (Cs{sub x}H{sub 3-x}PW{sub 12}O{sub 40}) were formed in the CsHSO{sub 4}-H{sub 3}PW{sub 12}O{sub 40} system by mechanochemical treatment. SPEEK was prepared from PEEK by sulfonation using concentrated sulfuric acid. Flexible composite electrolytes were obtained and their electrochemical properties were markedly improved with the addition of Cs{sub x}H{sub 3-x}PW{sub 12}O{sub 40}, into the SPEEK matrix. A maximum power density of 213 mW cm{sup -2} was obtained from the single cell test for 50H{sub 3}PW{sub 12}O{sub 40}-50CsHSO{sub 4} in SPEEK (1/5 by weight) composite electrolyte at 80 deg. C and at 80 RH%. Electrochemical properties and transmission electron microscopy (TEM) results suggest that three-dimensional cluster particles were formed and homogeneously distributed in the SPEEK matrix. The mechanochemically synthesized Cs{sub x}H{sub 3-x}PW{sub 12}O{sub 40} incorporated into the SPEEK matrix increased the number of protonate sites in the electrolyte. The composite electrolytes were successfully formed with Cs{sub x}H{sub 3-x}PW{sub 12}O{sub 40}, which consist of hydrogen bonding between surface of inorganic solid acids and not only -HSO{sub 4}{sup -} dissociated from CsHSO{sub 4} but also -SO{sub 3}H groups in the SPEEK.

Electrocatalytic oxidation and voltammetric determination of ciprofloxacin employing poly(alizarin red)/graphene composite film in the presence of ascorbic acid, uric acid and dopamine

Energy Technology Data Exchange (ETDEWEB)

Zhang, Xin; Wei, Youli; Ding, Yaping, E-mail: wdingyp@sina.com

2014-07-04

Graphical abstract: An electrochemical sensor based on PAR/EGR/GCE via a cooperation of the potentiostatic technique and cyclic voltammetry was first fabricated for the determination of CPFX with satisfied detecting result of real samples. - Highlights: • PAR/EGR composite film was prepared for the first time. • The sensor can be applied to determinate CPFX in the presence of AA, UA and DA. • The sensor indicated the feasibility in drug samples and biological media. - Abstract: A glassy carbon electrode modified with poly(alizarin red)/electrodeposited graphene (PAR/EGR) composite film was prepared and applied to detect ciprofloxacin (CPFX) in the presence of ascorbic, uric acid and dopamine. The morphology and interface property of PAR/EGR films were examined by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The electrocatalytic oxidation of CPFX on AR/EGR was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The linearity ranged from 4 × 10{sup −8} to 1.2 × 10{sup −4} M with a detection limit (S/N = 3) of 0.01 μM. The modified electrode could be applied to the individual determination of CPFX as well as the simultaneous determination of CPFX, ascorbic acid, uric acid and dopamine. This method proved to be a simple, selective and rapid way to determine CPFX in pharmaceutical preparation and biological media.

Electrocatalytic oxidation and voltammetric determination of ciprofloxacin employing poly(alizarin red)/graphene composite film in the presence of ascorbic acid, uric acid and dopamine

International Nuclear Information System (INIS)

Zhang, Xin; Wei, Youli; Ding, Yaping

2014-01-01

Graphical abstract: An electrochemical sensor based on PAR/EGR/GCE via a cooperation of the potentiostatic technique and cyclic voltammetry was first fabricated for the determination of CPFX with satisfied detecting result of real samples. - Highlights: • PAR/EGR composite film was prepared for the first time. • The sensor can be applied to determinate CPFX in the presence of AA, UA and DA. • The sensor indicated the feasibility in drug samples and biological media. - Abstract: A glassy carbon electrode modified with poly(alizarin red)/electrodeposited graphene (PAR/EGR) composite film was prepared and applied to detect ciprofloxacin (CPFX) in the presence of ascorbic, uric acid and dopamine. The morphology and interface property of PAR/EGR films were examined by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The electrocatalytic oxidation of CPFX on AR/EGR was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The linearity ranged from 4 × 10 −8 to 1.2 × 10 −4 M with a detection limit (S/N = 3) of 0.01 μM. The modified electrode could be applied to the individual determination of CPFX as well as the simultaneous determination of CPFX, ascorbic acid, uric acid and dopamine. This method proved to be a simple, selective and rapid way to determine CPFX in pharmaceutical preparation and biological media

On basicity and composition of molybdogermanium heteropoly acid

International Nuclear Information System (INIS)

Mirzoyan, F.V.; Tarayan, V.M.; Petrosyam, A.A.

1984-01-01

The data on the number of single-charged cations of the basic dye (BD) associated by anion of molybdogermanium heteropoly acid equal to effective acid basicity, as well as the data on chemical analysis of formed solid-phase BD-MGA compounds were used to establish that composition and basicity of MGA depend on the nature of dye-precipitator. The use of acridine orange results in stabilization and precipitation of octasubstituted 12MGA salt, and acriflavine-tetrasubstituted 8MGA salt. Formation of the last ones is independent of medium acidity in its wide range: pH 0.45-4.80 and pH 0-3.8 respectively

Fatty acid composition of meat of Sarda suckling lamb

OpenAIRE

Manca, Maria Grazia

2011-01-01

The fatty acid composition of dietary fat has an important role in human nutrition because can help to reduce the risk of appearance of some diseases. In this work fatty acid profile of meat of Sarda suckling lamb was studied in order to improve meat fat quality in relation to human health. Aim of this thesis was firstly to assess the effect of different management systems, indoor vs. outdoor, on fatty acid profile of meat of Sarda suckling lamb. Lambs which followed their mother on pasture h...

Electron spectroscopy of rubber and resin-based composites containing 2D carbon

International Nuclear Information System (INIS)

Kaciulis, S.; Mezzi, A.; Balijepalli, S.K.; Lavorgna, M.; Xia, H.S.

2015-01-01

Composite materials with 2D carbon (graphene and/or single wall carbon nanotubes) are very promising due to their extraordinary electrical and mechanical properties. Graphene and natural rubber composites, which may be used for the gaskets or sealants, were prepared by ultrasonically assisted latex-mixing exfoliation and in-situ reduction process, with two vulcanization approaches: roll-mixing and hot-pressing. Also the resin-based composites, filled with micro-particles of Ag and graphene or carbon nanotubes, have been studied. The standards for the compositional characterization of these materials still are not established. In addition to the mostly used techniques, such as Raman spectroscopy and electron microscopy, also Auger electron spectroscopy can be employed for the identification of graphene. In this study, the shape of C KVV peak, excited by electron beam and X-ray photons, has been investigated in different composite materials containing graphene and carbon nanotubes. A spectroscopic method for 2D carbon recognition, based on the D x parameter which is determined from C KVV signal excited by X-ray photons, was proposed and verified. Even a small content of graphene in different types of composites was sufficient for this recognition due to the dominating presence of graphene on the surface of composites. - Highlights: • Chemical composition of the rubber composites was determined by XPS. • Auger spectrum of carbon was used for graphene identification in composites. • Small content of graphene was sufficient for its recognition from the D parameter

Electron spectroscopy of rubber and resin-based composites containing 2D carbon

Energy Technology Data Exchange (ETDEWEB)

Kaciulis, S., E-mail: saulius.kaciulis@ismn.cnr.it [Institute for the Study of Nanostructured Materials, ISMN-CNR, P.O. Box 10, Monterotondo Stazione, 00015 Roma (Italy); Mezzi, A.; Balijepalli, S.K. [Institute for the Study of Nanostructured Materials, ISMN-CNR, P.O. Box 10, Monterotondo Stazione, 00015 Roma (Italy); Lavorgna, M. [Institute of Polymers, Composites and Biomaterials, IPCB-CNR, P.le Fermi, 80055 Napoli (Italy); Xia, H.S. [State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, 610065 Sichuan (China)

2015-04-30

Composite materials with 2D carbon (graphene and/or single wall carbon nanotubes) are very promising due to their extraordinary electrical and mechanical properties. Graphene and natural rubber composites, which may be used for the gaskets or sealants, were prepared by ultrasonically assisted latex-mixing exfoliation and in-situ reduction process, with two vulcanization approaches: roll-mixing and hot-pressing. Also the resin-based composites, filled with micro-particles of Ag and graphene or carbon nanotubes, have been studied. The standards for the compositional characterization of these materials still are not established. In addition to the mostly used techniques, such as Raman spectroscopy and electron microscopy, also Auger electron spectroscopy can be employed for the identification of graphene. In this study, the shape of C KVV peak, excited by electron beam and X-ray photons, has been investigated in different composite materials containing graphene and carbon nanotubes. A spectroscopic method for 2D carbon recognition, based on the D{sub x} parameter which is determined from C KVV signal excited by X-ray photons, was proposed and verified. Even a small content of graphene in different types of composites was sufficient for this recognition due to the dominating presence of graphene on the surface of composites. - Highlights: • Chemical composition of the rubber composites was determined by XPS. • Auger spectrum of carbon was used for graphene identification in composites. • Small content of graphene was sufficient for its recognition from the D parameter.

Graphene for amino acid biosensing: Theoretical study of the electronic transport

Science.gov (United States)

Rodríguez, S. J.; Makinistian, L.; Albanesi, E. A.

2017-10-01

The study of biosensors based on graphene has increased in the last years, the combination of excellent electrical properties and low noise makes graphene a material for next generation electronic devices. This work discusses the application of a graphene-based biosensor for the detection of amino acids histidine (His), alanine (Ala), aspartic acid (Asp), and tyrosine (Tyr). First, we present the results of modeling from first principles the adsorption of the four amino acids on a graphene sheet, we calculate adsorption energy, substrate-adsorbate distance, equilibrium geometrical configurations (upon relaxation) and densities of states (DOS) for each biomolecule adsorbed. Furthermore, in order to evaluate the effects of amino acid adsorption on the electronic transport of graphene, we modeled a device using first-principles calculations with a combination of Density Functional Theory (DFT) and Nonequilibrium Greens Functions (NEGF). We provide with a detailed discussion in terms of transmission, current-voltage curves, and charge transfer. We found evidence of differences in the electronic transport through the graphene sheet due to amino acid adsorption, reinforcing the possibility of graphene-based sensors for amino acid sequencing of proteins.

Physical properties of wood-polymer composites prepared by an electron beam accelerator

International Nuclear Information System (INIS)

Yoshizawa, S.; Handa, T.; Fukuoka, M.; Hashizume, Y.; Nakamura, T.

1981-01-01

The dual characteristics in the performance of polymers in wood-polymer composites systems have been pursued with regard to the resolution of mechanical anisotropy of wood and the improvement in dimensional stability. The objective of the present study is to pursue the polymerization mechanism in wood under electron beam irradiation and the temperature dependence of polymer-wood interactions induced at various levels of higher order structure of wood in order to understand the polymer performance. Veneers used in the study were of rotary-cut beech (Fagus crenata Blume) 0.65 mm thick. All samples were oven-dried in vacuo at 80 0 C for 30 hr. The monomers used in the study were methyl methacrylate, styrene, acrylic acid, acrylonitrile, and unsaturated polyester. Experimental details are given. Results are given and discussed. (U.K.)

Electronic coupling through natural amino acids

Energy Technology Data Exchange (ETDEWEB)

Berstis, Laura; Beckham, Gregg T., E-mail: michael.crowley@nrel.gov, E-mail: gregg.beckham@nrel.gov; Crowley, Michael F., E-mail: michael.crowley@nrel.gov, E-mail: gregg.beckham@nrel.gov [National Renewable Energy Laboratory, National Bioenergy Center, 15013 Denver West Pkwy, Golden, Colorado 80401 (United States)

2015-12-14

Myriad scientific domains concern themselves with biological electron transfer (ET) events that span across vast scales of rate and efficiency through a remarkably fine-tuned integration of amino acid (AA) sequences, electronic structure, dynamics, and environment interactions. Within this intricate scheme, many questions persist as to how proteins modulate electron-tunneling properties. To help elucidate these principles, we develop a model set of peptides representing the common α-helix and β-strand motifs including all natural AAs within implicit protein-environment solvation. Using an effective Hamiltonian strategy with density functional theory, we characterize the electronic coupling through these peptides, furthermore considering side-chain dynamics. For both motifs, predictions consistently show that backbone-mediated electronic coupling is distinctly sensitive to AA type (aliphatic, polar, aromatic, negatively charged and positively charged), and to side-chain orientation. The unique properties of these residues may be employed to design activated, deactivated, or switch-like superexchange pathways. Electronic structure calculations and Green’s function analyses indicate that localized shifts in the electron density along the peptide play a role in modulating these pathways, and further substantiate the experimentally observed behavior of proline residues as superbridges. The distinct sensitivities of tunneling pathways to sequence and conformation revealed in this electronic coupling database help improve our fundamental understanding of the broad diversity of ET reactivity and provide guiding principles for peptide design.

The effect of poly (lactic-co-glycolic) acid composition on the mechanical properties of electrospun fibrous mats.

Science.gov (United States)

Liu, X; Aho, J; Baldursdottir, S; Bohr, A; Qu, H; Christensen, L P; Rantanen, J; Yang, M

2017-08-30

The aim of this study was to investigate the influence of polymer molecular structure on the electrospinnability and mechanical properties of electrospun fibrous mats (EFMs). Polymers with similar molecular weight but different composition ratios (lactic acid (LA) and glycolic acid (GA)) were dissolved in binary mixtures of N,N-dimethylformamide (DMF) and tetrahydrofuran (THF). The intrinsic viscosity and rheological properties of polymer solutions were investigated prior to electrospinning. The morphology and mechanical properties of the resulting EFMs were characterized by scanning electron microscope (SEM) and dynamic mechanical analysis (DMA). Sufficiently high inter-molecular interactions were found to be a prerequisite to ensure the formation of fibers in the electrospinning process, regardless the polymer composition. The higher the amount of GA in the polymer composition, the more ordered and entangled molecules were formed after electrospinning from the solution in THF-DMF, which resulted in higher Young's modulus and tensile strength of the EFMs. In conclusion, this study shows that the mechanical properties of EFMs, which depend on the polymer molecule-solvent affinity, can be predicted by the inter-molecular interactions in the starting polymer solutions and over the drying process of electrospinning. Copyright © 2017 Elsevier B.V. All rights reserved.

Muscle and genotype effects on fatty acid composition of goat kid intramuscular fat

Directory of Open Access Journals (Sweden)

Valeriano Domenech

2011-07-01

Full Text Available Little is known about the fatty acid composition of the major muscles in goats from different breeds. Forty entire male suckling kids, 20 Criollo Cordobes and 20 Anglo Nubian, were slaughtered at 75 days of age and the fatty acid composition of their longissimus thoracis (LT and semitendinosus (ST muscles was analysed to clarify the effects of genotype and muscle type on goat kid meat. Genotype had a great influence on the fatty acid composition of goat kid meat. Meat from Criollo Cordobes had greater saturated (P<0.001 and lower monounsaturated (P<0.001 and polyunsaturated fatty acids (P=0.002 concentration than meat from Anglo Nubian, showing higher saturated fatty acids (SFA. On the other hand, intramuscular fat content from both genotypes was higher (P=0.042 in ST muscle, while the lowest cholesterol levels were observed in ST of Criollo Cordobes (P=0.038. That higher fat content resulted in lower relative contents of total polyunsaturated (P<0.001 and n-3 (P=0.002 fatty acids due to the lower contribution of the membrane phospholipids.

Optimization of Palmitic Acid Composition in Crude Oleic Acid to Provide Specifications of Titer and Cloud Point of Distillate Oleic Acid using a Flash Distiller

Directory of Open Access Journals (Sweden)

Muhammad Yusuf Ritonga

2010-11-01

Full Text Available Titer and cloud point of Distilled Oleic Acid is higher than is the standard on feed composition palmitic acid (C15H31COOH or C16 11.2 %. Feed composition C16, top temperature precut and bottom main distiller column were optimized to produce DOA. A factorial design with 3 independent variables, 3 X 2 X 3, repeated twice as much, is applied to observe effects of feed composition C16 to quality parameters. In the optimum C16, feed composition at 5.20 % produced DOA with titer 6.8 oC, cloud point 5.0 oC (inside its specification.

Fatty Acid Composition of the Aerial Parts of Some Centaurea ...

African Journals Online (AJOL)

Purpose: To evaluate the fatty acid composition of six Centaurea species, viz, Centaurea behen, C. saligna, C. depressa, C. urvillei subsp. urvillei, C. urvillei subsp. hayekiana and C. aggregata subsp. aggregata, from Elaz.., Turkey. Methods: Fatty acid methyl esters (FAMEs) of the oil extracts of four Centaurea species were ...

Electronic-state control of amino acids on semiconductor surfaces

International Nuclear Information System (INIS)

Oda, Masato; Nakayama, Takashi

2005-01-01

Electronic structures of amino acids on the Si(1 1 1) surfaces are investigated by using ab initio Hartree-Fock calculations. It is shown that among various polar amino acids, a histidine is the only one that can be positively ionized when hole carriers are supplied in the Si substrate, by transferring the hole charge from Si substrate to an amino acid. This result indicates that the ionization of a histidine, which will activate the protein functions, can be controlled electrically by producing amino acid/Si junctions

Determination of feedstuff amino acids composition by ion-exchange chromatography

Directory of Open Access Journals (Sweden)

A. A. Volnin

2018-01-01

Full Text Available Determination of animal feeds amino acids composition is the very important part of agricultural sciences and livestock management. This is necessary for normalization and balanced of farm animal’s diets parameters. Advances in husbandry techniques are making in response to the needs for rearing high genetic merit livestock. The nutrition of livestock has a critical role in these developments and is an element which needs to be continually updated as new scientific information becomes available. This article is devoted to the use of ion-exchange chromatography with post-colum derivatization by ninhydrin in the study of the amino acid composition and evaluation of the biological value of livestock feedstuff components. The amino acid composition (except tryptophan of the livestock feed-stuff component is presented for threonine – 3.26 g/100g of protein, leucine – 6.43, isoleucine – 3.24, valine – 4.77, methionine – 2.18, lysine – 2.90, phenylalanine – 3.16, histidine – 2.03, tyrosine – 2.33, sum of asparagine and aspartate – 6.76, serine – 3.97, sum of glutamine and glutamic acid – 12.04, glycine – 6.00, alanine – 6.71, arginine – 6.93, proline – 3.08, sum of cystine and cysteine – 1.38. Biological value of feedstuff component compared with the "ideal" protein (FAO WHO is estimated, limiting amino acids were found. The amino acid score was calculated: for threonine – 81.5%, leucine – 91.9%, isoleucine – 81%, valine – 95.4%, lysine – 52.7%, phenylalanine and tyrosine sum – 91.5%, methionine and cysteine sum – 101.7%. Feedstuff component had a low level of essential amino acids in compare with "ideal" protein (FAO WHO. Feedstuff component can be used for livestock nutrition as a component of essential amino-acid balanced diet.

Influence of polymer swelling and dissolution into food simulants on the release of graphene nanoplates and carbon nanotubes from poly(lactic) acid and polypropylene composite films

OpenAIRE

Velichkova, Hristiana; Petrova, Ivanka; Kotsilkov, Stanislav; Ivanov, Evgeni; Vitanov, Nikolay K.; Kotsilkova, Rumiana

2017-01-01

The study compared the effects of swelling and dissolution of a matrix polymer by food simulants on the release of graphene nanoplates (GNPs) and multiwall carbon nanotubes (MWCNTs) from poly(lactic) acid (PLA) and polypropylene (PP) composite films. The total migration was determined gravimetrically in the ethanol and acetic acid food simulants at different time and temperature conditions, while migrants were detected by laser diffraction analysis and transmission electron microscopy. Swelli...

Fatty acid compositions of triglycerides and free fatty acids in sebum depend on amount of triglycerides, and do not differ in presence or absence of acne vulgaris.

Science.gov (United States)

Akaza, Narifumi; Akamatsu, Hirohiko; Numata, Shigeki; Matsusue, Miyuki; Mashima, Yasuo; Miyawaki, Masaaki; Yamada, Shunji; Yagami, Akiko; Nakata, Satoru; Matsunaga, Kayoko

2014-12-01

To clarify the influence of the fatty acid composition of sebum in acne vulgaris, we investigated the amounts and fatty acid compositions of triglycerides (TG) and free fatty acids (FFA), and the amounts of cutaneous superficial Propionibacterium acnes in acne patients and healthy subjects. The foreheads of 18 female patients, 10 male patients, 10 healthy females and 10 healthy males were studied in a Japanese population. There were significant differences in the amounts of sebum, TG and cutaneous superficial P. acnes, as well as the fatty acid compositions of TG and FFA between acne patients and healthy subjects in females. Their fatty acid compositions were correlated with the amount of TG with or without acne. It was clarified that the fatty acid compositions of TG and FFA depended on the amount of TG, and there were no differences in the fatty acid composition in the presence and absence of acne. © 2014 Japanese Dermatological Association.

Stearic acid coating on circulating fluidized bed combustion fly ashes and its effect on the mechanical performance of polymer composites

Energy Technology Data Exchange (ETDEWEB)

Yao, Nina [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); Zhang, Ping, E-mail: pingzhang@swust.edu.cn [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); School of Material Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010 (China); Song, Lixian; Kang, Ming; Lu, Zhongyuan [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); School of Material Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010 (China); Zheng, Rong [Sichuan Jinhe Group Co., Ltd., Mianyang 621010 (China)

2013-08-15

The aim of this work was to test circulating fluidized bed combustion fly ashes (CFAs) for its potential to be utilized in polymer composites manufacturing to improve its toughness. CFAs was coated by stearic acid and used in the composite of polypropylene/ethylene vinyl acetate/high density polyethylene (PP/EVA/HDPE) by molding process method. The resulting coated and uncoated CFAs were fully characterized by particle size analyzer, contact angles, powder X-ray diffraction (XRD), thermogravimetric analysis/differential thermal analysis (TGA/DTA), Brunauer–Emmett–Teller (BET), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The stearic acid coated onto the surface of CFAs particles in the physical and chemical ways, and the total clad ratio reached 2.05% by measuring TGA/DTA curve. The percentage of CFAs particles focused to a narrow range 2–4 μm and the median mean size was 3.2 μm more than uncoated CFAs. The properties of hydrophobic and dispersive of CFAs particles improved and original activity was reserved after stearic acid coating. The stearic acid was verified as a coupling agent by how much effect it had on the mechanical properties. It showed the elongation at break of PP/EVA/HDPE reinforced with 15 wt% coated CFAs (c-CFAs) was 80.20% and higher than that of the uncoated. The stearic acid treatment of CFAs is a very promising approach to improve the mechanical strength due to the incorporation of stearic acid on the CFAs surface, and hence, further enhances the potential for recycling CFAs as a suitable filler material in polymer composites.

Stearic acid coating on circulating fluidized bed combustion fly ashes and its effect on the mechanical performance of polymer composites

International Nuclear Information System (INIS)

Yao, Nina; Zhang, Ping; Song, Lixian; Kang, Ming; Lu, Zhongyuan; Zheng, Rong

2013-01-01

The aim of this work was to test circulating fluidized bed combustion fly ashes (CFAs) for its potential to be utilized in polymer composites manufacturing to improve its toughness. CFAs was coated by stearic acid and used in the composite of polypropylene/ethylene vinyl acetate/high density polyethylene (PP/EVA/HDPE) by molding process method. The resulting coated and uncoated CFAs were fully characterized by particle size analyzer, contact angles, powder X-ray diffraction (XRD), thermogravimetric analysis/differential thermal analysis (TGA/DTA), Brunauer–Emmett–Teller (BET), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The stearic acid coated onto the surface of CFAs particles in the physical and chemical ways, and the total clad ratio reached 2.05% by measuring TGA/DTA curve. The percentage of CFAs particles focused to a narrow range 2–4 μm and the median mean size was 3.2 μm more than uncoated CFAs. The properties of hydrophobic and dispersive of CFAs particles improved and original activity was reserved after stearic acid coating. The stearic acid was verified as a coupling agent by how much effect it had on the mechanical properties. It showed the elongation at break of PP/EVA/HDPE reinforced with 15 wt% coated CFAs (c-CFAs) was 80.20% and higher than that of the uncoated. The stearic acid treatment of CFAs is a very promising approach to improve the mechanical strength due to the incorporation of stearic acid on the CFAs surface, and hence, further enhances the potential for recycling CFAs as a suitable filler material in polymer composites.

Study on preparation and thermal property of binary fatty acid and the binary fatty acids/diatomite composite phase change materials

International Nuclear Information System (INIS)

Li, Min; Kao, Hongtao; Wu, Zhishen; Tan, Jinmiao

2011-01-01

This study prepared a series of binary phase change materials by mixing decanoic acid, dodecanoic acid, hexadecanoic acid and octadecanoic acid each other. The phase-transition temperature of binary fatty acid and its corresponding mixing proportion are calculated with phase diagram thermodynamic method. The results are verified by the experimental result of the heat absorption curve and the Differential Scanning Calorimetry (DSC) analysis curve. The results show that the calculation method of phase diagram thermodynamic calculation can be taken as a basis for mixing proportion of binary fatty acid phase change materials. In addition, the decanoic-dodecanoic acid/diatomite composite phase change material (PCM) are prepared and its microstructure, thermal property and thermal reliability are characterized. The result shows that the decanoic-dodecanoic acid is uniformly adsorbed into diatomite and the form-stable PCM are formed. The phase-transition temperature and the latent heat of the decanoic-dodecanoic acid/diatomite composite PCMs is 16.74 o C and 66.8114 J/g, respectively.

Fatty Acid Composition of Meat from Ruminants, with Special Emphasis on trans Fatty Acids

DEFF Research Database (Denmark)

Leth, Torben; Ovesen, L.; Hansen, K.

1998-01-01

The fatty acid composition was determined in 39 samples of beef, 20 samples of veal, and 34 samples of lamb, representative of the supply of ruminant meat in Denmark. Five cuts of beef and veal and three cuts of lamb with increasing fat content were selected, and analysis of the fatty acid methyl...... esters was performed by gas-liquid chromatography (GLC) on a polar 50-m capillary column CP Sil 88 with flame-ionization detection. Lamb had the highest content of saturated fatty acids (52.8 +/- 1.8 g/100 g fatty acids), higher than beef and veal (45.3 +/- 3.1 and 45.4 +/- 0.8 g/100 g fatty acids......, respectively). Cis monounsaturated fatty acids were 49.2 +/- 3.1, 44.9 +/- 1.8, and 37.7 +/- 1.7, and polyunsaturated fatty acids were 3.3 +/- 0.7, 5.8 +/- 2.0, and 5.0 +/- 0.1 g/100 g fatty acids in beef, veal, and lamb, respectively. Beef contained 2.1 +/- 0.8 g trans C-18:1 per 100 g fatty acids, about half...

Relationship between fatty acid composition and biodiesel quality for nine commercial palm oils

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Chanida Lamaisri

2015-08-01

Full Text Available Biodiesel is an alternative fuel consisting of alkyl esters of fatty acids from vegetable oils or animal fats. The fatty acid compositions in the oils used as feedstock can influence quality of the biodiesel. In the present study, oil content and fatty acid composition of mesocarp and kernel oil were examined from nine commercial oil palm Elaeis guineensis cultivars. Saponification number, iodine value and cetane number were calculated from palm oil fatty acid methyl ester compositions. Fruits of tenera oil palm were collected from a farmer’s plantation in Dan Makham Tia District, Kanchanaburi Province in 2009. Variation between cultivars was observed in oil content and fatty acid profile of mesocarp oil rather than kernel oil. The percentage of oil in dry mesocarp ranged from 63.8% to 74.9%. The mesocarp oil composed of 41.5 - 51.6% palmitic acid, 3.58-7.10% stearic acid, 32.8-42.5% oleic acid and 9.3-13.0% linoleic acid. Likewise saponification number, iodine value and cetane number of mesocarp oil fatty acid methyl ester showed more variation among cultivars, ranging from 196.5-198.9, 45.7-54.6 and 61.8-63.6, respectively. While those of kernel oil fatty acid methyl ester showed no different among cultivars, ranging from 229-242, 13.6-16.4 and 65.3-66.5, respectively. The cetane number of fatty acid methyl ester positively correlated with contents of myristic, palmitic and stearic acids in palm oil and saponification number of biodiesel, but negatively correlated with iodine value

Evolution of proteomes: fundamental signatures and global trends in amino acid compositions

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Yeramian Edouard

2006-12-01

Full Text Available Abstract Background The evolutionary characterization of species and lifestyles at global levels is nowadays a subject of considerable interest, particularly with the availability of many complete genomes. Are there specific properties associated with lifestyles and phylogenies? What are the underlying evolutionary trends? One of the simplest analyses to address such questions concerns characterization of proteomes at the amino acids composition level. Results In this work, amino acid compositions of a large set of 208 proteomes, with significant number of representatives from the three phylogenetic domains and different lifestyles are analyzed, resorting to an appropriate multidimensional method: Correspondence analysis. The analysis reveals striking discrimination between eukaryotes, prokaryotic mesophiles and hyperthemophiles-themophiles, following amino acid usage. In sharp contrast, no similar discrimination is observed for psychrophiles. The observed distributional properties are compared with various inferred chronologies for the recruitment of amino acids into the genetic code. Such comparisons reveal correlations between the observed segregations of species following amino acid usage, and the separation of amino acids following early or late recruitment. Conclusion A simple description of proteomes according to amino acid compositions reveals striking signatures, with sharp segregations or on the contrary non-discriminations following phylogenies and lifestyles. The distribution of species, following amino acid usage, exhibits a discrimination between [high GC]-[high optimal growth temperatures] and [low GC]-[moderate temperatures] characteristics. This discrimination appears to coincide closely with the separation of amino acids following their inferred early or late recruitment into the genetic code. Taken together the various results provide a consistent picture for the evolution of proteomes, in terms of amino acid usage.

Modeling molecular acidity with electronic properties and Hammett constants for substituted benzoic acids.

Science.gov (United States)

Huang, Ying; Liu, Lianghong; Liu, Wanhui; Liu, Shaogang; Liu, Shubin

2011-12-29

Molecular acidity is an important physiochemical property essential in many fields of molecular studies, but an efficient and reliable computational approach to make accurate predictions is still missing. In this work, based on our previous studies to use gas phase electronic properties such as molecular electrostatic potential and valence natural atomic orbitals of the acidic atom and leaving proton, we demonstrate here that different approaches can be employed to tackle this problem. To that end, we employ 196 singly, doubly, and triply substituted benzoic acids for the study. We show that two different approaches are possible, one focusing on the carboxyl group through its localized electronic properties and the other on the substituting groups via Hammett constants and their additivity rule. Our present results clearly exhibit that with the linear models built from the singly substituted species, one can accurately predict the pK(a) values for the doubly and triply substituted species with both of these two approaches. The predictions from these approaches are consistent with each other and agree well with the experimental data. These intrinsically different approaches are the two manifestations of the same molecular acidity property, both valid and complementary to each other. © 2011 American Chemical Society

Changes in phosphatidylcholine fatty acid composition are associated with altered skeletal muscle insulin responsiveness in normal man.

Science.gov (United States)

Clore, J N; Harris, P A; Li, J; Azzam, A; Gill, R; Zuelzer, W; Rizzo, W B; Blackard, W G

2000-02-01

The fatty acid composition of skeletal muscle cell membrane phospholipids (PLs) is known to influence insulin responsiveness in man. We have recently shown that the fatty acid composition of phosphatidylcholine (PC), and not phosphatidylethanolamine (PE), from skeletal muscle membranes is of particular importance in this relationship. Efforts to alter the PL fatty acid composition in animal models have demonstrated induction of insulin resistance. However, it has been more difficult to determine if changes in insulin sensitivity are associated with changes in the skeletal muscle membrane fatty acid composition of PL in man. Using nicotinic acid (NA), an agent known to induce insulin resistance in man, 9 normal subjects were studied before and after treatment for 1 month. Skeletal muscle membrane fatty acid composition of PC and PE from biopsies of vastus lateralis was correlated with insulin responsiveness using a 3-step hyperinsulinemic-euglycemic clamp. Treatment with NA was associated with a 25% increase in the half-maximal insulin concentration ([ED50] 52.0 +/- 7.5 to 64.6 +/- 9.0 microU/mL, P insulin sensitivity. Significant changes in the fatty acid composition of PC, but not PE, were also observed after NA administration. An increase in the percentage of 16:0 (21% +/- 0.3% to 21.7% +/- 0.4%, P insulin resistance with NA is associated with changes in the fatty acid composition of PC in man.

Turkey-hen amino acid composition of brain and eyes

International Nuclear Information System (INIS)

Adeyeye, E.I.

2015-01-01

The amino acids composition of the brain and eyes of the mature Turkey-hen (Meleagris gallopavo L.), were determined on dry weight basis. Total essential amino acids ranged from 35.1-36.0 g/100 g as 49.5-49.8% of the total amino acids. The amino acid score showed that lysine ranged from 0.76-0.91 (on whole hen.s egg comparison), 0.85-1.03 (on provisional essential amino acid scoring pattern), and 0.81-0.98 (on suggested requirement of the essential amino acid of a preschool child). The predicted protein efficiency ratio was 1.94-2.41, whilst essential amino acid index range was 1.06-1.08 and the calculated isoelectric point range was 3.97-4.18. The correlation coefficient (rxy) was positively high and significant at r = 0.01 for the total amino acids, amino acid scores (on the whole hen.s egg comparisons made) and the isoelectric point. On the whole, the eyes were better in 12/18 or 66.7% parameters of the amino acids than the brain of Turkey-Hen. (author)

Effect of electron beam irradiation on nutritional ingredient of Tegillarca granosa meat

International Nuclear Information System (INIS)

Li Chao; Yang Wenge; Xu Dalun; Ou Changrong; Shi Huidong

2011-01-01

The influences of 0, 1, 3, 5, 7 and 9 kGy electron beam irradiation on the contents of protein and amino acid and the composition of amino acids and fatty acids in Tegillarca granosa meat were investigated. The results showed that the electron beam had no significant effect on contents of moisture, ash and protein. Fat was sensitive to electron beam irradiation, which decreased with the increasing of irradiation dose. The composition of amino acids remained stable with different doses. The values of EAA/TAA and EAA/NEAA were kept in accordance with FAO/WHO protein model. Besides, electron beam irradiation made no effect on the limiting amino acid (the first and second limiting amino acids were Met + Cys and Val, respectively). The relative content of PUFA increased significantly 1 ∼ 7 kGy irradiation. Electron beam irradiation produced a notable impact on the essential fatty acid, induced the increase of linoleic acid, linolenic acid and arachidonic acid at the doses of 5 ∼ 9 kGy. After the irradiation of 9 kGy, the increments of relative contents of the three essential fatty acids reached 94.61%, 41.37% and 89.91%, respectively. Electron beam irradiation had positive effect on EPA with the doses of 3, 5 and 9 kGy. However, DHA was sensitive to electron beam irradiation, whose relative content decreased with the increasing of irradiation dose and undetected at the dose of 9 kGy. According to the research of decontamination effect, the recommended dose of electron beam irradiation on Tegillarca granosa ws fixed at 3 ∼ 5 kGy. (authors)

Additive Manufacturing and Characterization of Polylactic Acid (PLA) Composites Containing Metal Reinforcements

Science.gov (United States)

Kuentz, Lily; Salem, Anton; Singh, M.; Halbig, M. C.; Salem, J. A.

2016-01-01

Additive manufacturing of polymeric systems using 3D printing has become quite popular recently due to rapid growth and availability of low cost and open source 3D printers. Two widely used 3D printing filaments are based on polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) systems. PLA is much more environmentally friendly in comparison to ABS since it is made from renewable resources such as corn, sugarcane, and other starches as precursors. Recently, polylactic acid-based metal powder containing composite filaments have emerged which could be utilized for multifunctional applications. The composite filaments have higher density than pure PLA, and the majority of the materials volume is made up of polylactic acid. In order to utilize functionalities of composite filaments, printing behavior and properties of 3-D printed composites need to be characterized and compared with the pure PLA materials. In this study, pure PLA and composite specimens with different metallic reinforcements (Copper, Bronze, Tungsten, Iron, etc) were 3D printed at various layer heights and resulting microstructures and properties were characterized. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) behavior of filaments with different reinforcements were studied. The microscopy results show an increase in porosity between 3-D printed regular PLA and the metal composite PLA samples, which could produce weaker mechanical properties in the metal composite materials. Tensile strength and fracture toughness behavior of specimens as a function of print layer height will be presented.

What shapes amino acid and sugar composition in Mediterranean floral nectars?

NARCIS (Netherlands)

Petanidou, T.; Van Laere, A.; Ellis, W.; Smets, E.

2006-01-01

We studied the amino acid (AA) composition of the floral nectars of 73 plant species occurring in a phryganic (East Mediterranean garrigue) community and investigated whether AA and sugar composition is shaped by evolutionary (plant phylogeny), ecological (flowering time as a direct effect of summer

Preparation and properties of shape-stabilized phase change materials based on fatty acid eutectics and cellulose composites for thermal energy storage

International Nuclear Information System (INIS)

Cao, Lei; Tang, Yaojie; Fang, Guiyin

2015-01-01

Shape-stabilized fatty acid eutectics/carboxy methyl cellulose-1 composites as phase change materials (PCMs) were synthesized by absorbing liquid eutectics into the carboxy methyl cellulose-1 fibers. The chemical structure, crystalloid phase and morphology were determined by the Fourier transformation infrared spectroscope, X-ray diffractometer and scanning electronic microscope. The thermal properties and thermal stability were measured by the differential scanning calorimeter, thermogravimetric analyzer and the thermal cycling test, respectively. The results indicate that the eutectics are well adsorbed in the porous structure of the carboxy methyl cellulose-1. According to the DSC (differential scanning calorimeter) results, the composites melt at 32.2 °C with latent heat of 114.6 kJ/kg and solidify at 29.2 °C with latent heat of 106.8 kJ/kg. The thermal cycling test proves that the composites have good thermal reliability. It is envisioned that the prepared shape-stabilized PCMs have considerable potential for developing their roles in thermal energy storage. - Highlights: • The fatty acid eutectic/carboxy methyl cellulose-1 composites as PCMs were prepared. • Chemical structure and microstructure of composites were determined by FT-IR and SEM. • Thermal properties and stabilities were investigated by DSC and TGA. • The thermal cycling test confirmed that the composite has good thermal reliability

Lightning current tests to evaluate vulnerability of electronics in composite structures

NARCIS (Netherlands)

Blaj, M.A.; Buesink, Frederik Johannes Karel; Damstra, G.C.; Leferink, Frank Bernardus Johannes

2010-01-01

Protecting highly sensitive electronics housed inside composite structures against lightning is a real challenge. The direct strike represents the worst-case scenario for composite structures. The electromagnetic field generated by an indirect lightning strike in the vicinity of highly sensitive

Preliminary research on amino acid composition and nutritional value of clover proteins

Directory of Open Access Journals (Sweden)

L. Kłyszejko-Stefanowicz

2015-06-01

Full Text Available The amino acid composition and nutritional value of 5 clover varieties including 3 Polish ones ('Gloria', 'Hruszowska', 'Skrzeszowicka' and 2 of foreign origin ('Rotra' and 'Violetta' were investigated. No significant differences in the total protein content (19.2–20.0% of dry matter as well as in qualitative amino acid composition were found among the clover varieties under examination. EAA index (Essential amino acid index calculated according to Oser for 'Gloria' and 'Hruszowska' showed the highest nutritional value was – 40. The lowest value of EAA index was found for 'Violetta' cvar. – 32, intermediate values however for Rotra and Skrzeszowicka was 37 and 36.

Fatty acid composition of symbiotic zooxanthellae in relation to their hosts.

Science.gov (United States)

Bishop, D G; Kenrick, J R

1980-10-01

Gymnodinoid dinoflagellate symbionts, commonly referred to as zooxanthellae, are widely distributed among marine invertebrates. It has been assumed that they represent only one species,Gymnodinium microadriaticum. The fatty acid composition of total lipids and galactolipids of zooxanthellae isolated from 8 species of corals, 3 species of clams and a foraminiferan have been analyzed and found to vary according to the host. For example, the content of eicosapentaenoic acid in clam zooxanthellae monogalactosyldiacylglycerol was less than 2%, whereas in the same lipid from coral zooxanthellae, the content ranged from 9 to 22%. Corresponding values for the acid in digalactosyl-diacylglycerol were 1-8% from clam zooxanthellae and 23-40% from coral zooxanthellae. Coral zooxanthellae monogalactosyldiacylglycerol contain higher levels of octadecatetraenoic acid than are found in digalactosyldiacylglycerol, whereas the reverse is true in clam zooxanthellae. The fatty acid composition of the lipids of an axenic culture of zooxanthellae isolated from the clamTridacna maxima are similar to those of cells freshly isolated from the host. The results suggest either that the host is capable of affecting the fatty acid metabolism of the symbiont or that different strains of zooxanthellae occur in corals and clams.

[The fat content and fatty acids composition in selected products of the convenience food].

Science.gov (United States)

Drzewicka, Maria; Grajeta, Halina; Kleczkowski, Jerzy

2012-01-01

An increasing pace of life and a lack of time for meals preparation at home, observed in many countries worldwide, have led to an increased consumption of convenient food products. This term refers to highly processed food products that are either ready-to-eat or may be consumed after short culinary processing. Convenience foods include: dinner courses, salads, cereals, creams, broths, pizzas, roasts, as well as frozen products ready-to-eat after short heat treatment. The aim of this study was to assess the fat content and fatty acids composition of frozen products belonging to convenience food. Material for analysis comprised of 30 following food products: fish and seafood products, pizza, casseroles and meat products. The fat content was determined using Folch method and the fatty acids composition using gas chromatography technique. The analyzed products contained from 1.2% to 26.9% of fat. The saturated fatty acids (SFA) content ranged from 8.7% to 53.2%, while the monounsaturated fatty acids (MUFA)--from 24.0% to 68.7% of total fatty acids. The polyunsaturated fatty acids (PUFA) percentage accounted for 8,1% to 48,8% and trans isomers--for 0.2% to 6.1% of total fatty acids. The fat and fatty acid contents showed large differences in products depending on their composition and preparation techniques declared by the producer. Most of the analyzed fish and seafood products were characterized by the fat content ranged from 11% to 14% with the high percentage of fatty acids favorable from nutritional point of view, MUFA and PUFA. The composition of fatty acids from pizza and casseroles was less favorable, due to high proportion of SFA and also trans isomers.

Associations between dietary n-6 and n-3 fatty acids and arachidonic acid compositions in plasma and erythrocytes in young and elderly Japanese volunteers

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Kawabata Terue

2011-08-01

Full Text Available Abstract Background We reported that the compositions of arachidonic acid (ARA in erythrocytes and plasma phospholipids (PL in the elderly were lower than those in the young, though the ARA intake was nearly identical. Objective We further analyzed data in four study groups with different ages and sexes, and determined that the blood ARA levels were affected by the kinds of dietary fatty acids ingested. Methods One hundred and four healthy young and elderly volunteers were recruited. Dietary records together with photographic records from 28 consecutive days were reviewed and the fatty acid composition in plasma lipid fractions and erythrocyte PL was analyzed. Results No correlations for ARA between dietary fatty acids and blood lipid fractions were observed. A significant negative correlation between eicosapentaenoic acid (EPA + docosahexaenoic acid (DHA intake and ARA composition in erythrocyte PL was observed. ARA composition in erythrocyte PL was significantly lower in elderly subjects than in young subjects, because EPA and DHA intake in elderly subjects was higher than in young subjects. However, after removing the effect of dietary EPA+DHA intake, the ARA composition in erythrocyte PL in elderly subjects was significantly lower than that in young subjects. Conclusions Changes in physical conditions with aging influenced the low ARA composition of erythrocyte in elderly subjects in addition to the effects of dietary EPA and DHA.

Fatty acid composition of Dioscorea dumetorum (Pax) varieties ...

African Journals Online (AJOL)

The purpose of the present investigation was to study the fatty acid compositions of edible and wild Dioscorea dumetorum (Pax) varieties harvested from farms and forests of Ikot Akpanabia village in Akwa Ibom State, Nigeria in order to evaluate their nutritional and biochemical significance. Tubers were conveyed from farm ...

Predicting membrane protein types by fusing composite protein sequence features into pseudo amino acid composition.

Science.gov (United States)

Hayat, Maqsood; Khan, Asifullah

2011-02-21

Membrane proteins are vital type of proteins that serve as channels, receptors, and energy transducers in a cell. Prediction of membrane protein types is an important research area in bioinformatics. Knowledge of membrane protein types provides some valuable information for predicting novel example of the membrane protein types. However, classification of membrane protein types can be both time consuming and susceptible to errors due to the inherent similarity of membrane protein types. In this paper, neural networks based membrane protein type prediction system is proposed. Composite protein sequence representation (CPSR) is used to extract the features of a protein sequence, which includes seven feature sets; amino acid composition, sequence length, 2 gram exchange group frequency, hydrophobic group, electronic group, sum of hydrophobicity, and R-group. Principal component analysis is then employed to reduce the dimensionality of the feature vector. The probabilistic neural network (PNN), generalized regression neural network, and support vector machine (SVM) are used as classifiers. A high success rate of 86.01% is obtained using SVM for the jackknife test. In case of independent dataset test, PNN yields the highest accuracy of 95.73%. These classifiers exhibit improved performance using other performance measures such as sensitivity, specificity, Mathew's correlation coefficient, and F-measure. The experimental results show that the prediction performance of the proposed scheme for classifying membrane protein types is the best reported, so far. This performance improvement may largely be credited to the learning capabilities of neural networks and the composite feature extraction strategy, which exploits seven different properties of protein sequences. The proposed Mem-Predictor can be accessed at http://111.68.99.218/Mem-Predictor. Copyright © 2010 Elsevier Ltd. All rights reserved.

Fatty Acid And Essential Oil Compositions Of The Seed Oil Of Five ...

African Journals Online (AJOL)

The fatty acid and essential oil compositions of the seed oil of Annona cherimola, A. muricata, A. reticulata, A. senegalensis and A. squamosa were investigated by GC and GC/MS spectra. About eleven fatty acids were identified of which oleic, gondoic, palmitic and stearic acids predominated in each sample, and others ...

Fatty acid composition of muscle and heart tissue of Nile perch ...

African Journals Online (AJOL)

The fatty acid composition in the heart tissue and muscle tissue of the Nile perch, Lates niloticus, and Nile tilapia, Oreochromis niloticus populations from Lakes Kioga and Victoria was determined by methanolysis and gas chromatography of the resulting fatty acid methyl esters. The analytical data were treated by ...

The relationship between fatty acid compositions and thermal stability of extra virgin olive oils

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Fayegh Moulodi

2014-11-01

Full Text Available Background: Fatty acids are one of the most important compounds in edible oils. Further, the stability of oils depends on the composition of fatty acids. So, this study was conducted to investigate the effect of fatty acid composition on the oxidative stability of extra virgin olive oils during the heating process. Methods: In total, eight samples of extra virgin olive oil were studied. To evaluate their thermal stability, the oils were heated at 120 ° C for 4 h and sampling was carried out in 2-hour intervals. Then, fatty acid composition, peroxide value, anisidine value and totox value were evaluated according to Iranian national standards. Results: Results showed a significantly direct correlation between Palmitoleic acid and Totox index in the second (r=0.786 and fourth hours (r=0.762, and between linoleic and Totox index in the second (r=0.643 and fourth hours (r=0.786. However, there was a significantly inverse relationship between oleic acid and Totox index in the fourth hour (r=-0.833. Conclusion: Result indicated that linoleic and Palmitoleic acids had a reducing effect on thermal stability of extra virgin olive oil after the second hour. But, Oleic acid caused a positive effect on thermal stability after the fourth hour. Thus, it is concluded that unsaturated fatty acids especially oleic acid affect the thermal stability at final hours.

Effects of electron-beam irradiation on HDPE/Brazil nut shell fiber composite

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Maiara S.; Sartori, Mariana N.; Oliveira, Rene R.; Moura, Esperidiana A.B., E-mail: maiara.sferreira@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

In recent years, research on the replacement of synthetic fibers by natural fibers as reinforcement in thermoplastic composites has increased dramatically due to the advantages of natural fibers, such as low density, low cost, environmental appeal and recyclability. In the present work, the influence of electron-beam irradiation on mechanical properties of HDPE and HDPE/Brazil Nut Shell (Bertholletia excelsa) fiber compositive was investigated. The HDPE composite reinforced with 5% or 10%, by weight of Brazil nut shell fiber powder with particle sizes equal or smaller than 250 μm were obtained by extrusion, using a twin screw extruder. The materials were irradiated at 200 kGy using a 1.5 MeV electron beam accelerator, at room temperature in presence of air. The irradiated and non-irradiated specimens tests samples were submitted to mechanical and thermo-mechanical tests, scanning electron microscopy (SEM), X-Ray diffraction (XRD) and sol-gel analysis and the correlation between their properties was discussed. The results showed significant changes in HDPE mechanical and thermo-mechanical properties due to Brazil nut shell fibers addition and electron-beam irradiation. The surface of the cryo fractured composite samples irradiated showed important visual changes which suggest a better fiber-matrix interfacial adhesion, due to irradiation treatment. These results showed that it is possible to get interesting property gains by using waste from renewable sources instead of the traditional ones and electron-beam radiation treatment. (author)

Effects of electron-beam irradiation on HDPE/Brazil nut shell fiber composite

International Nuclear Information System (INIS)

Ferreira, Maiara S.; Sartori, Mariana N.; Oliveira, Rene R.; Moura, Esperidiana A.B.

2013-01-01

In recent years, research on the replacement of synthetic fibers by natural fibers as reinforcement in thermoplastic composites has increased dramatically due to the advantages of natural fibers, such as low density, low cost, environmental appeal and recyclability. In the present work, the influence of electron-beam irradiation on mechanical properties of HDPE and HDPE/Brazil Nut Shell (Bertholletia excelsa) fiber compositive was investigated. The HDPE composite reinforced with 5% or 10%, by weight of Brazil nut shell fiber powder with particle sizes equal or smaller than 250 μm were obtained by extrusion, using a twin screw extruder. The materials were irradiated at 200 kGy using a 1.5 MeV electron beam accelerator, at room temperature in presence of air. The irradiated and non-irradiated specimens tests samples were submitted to mechanical and thermo-mechanical tests, scanning electron microscopy (SEM), X-Ray diffraction (XRD) and sol-gel analysis and the correlation between their properties was discussed. The results showed significant changes in HDPE mechanical and thermo-mechanical properties due to Brazil nut shell fibers addition and electron-beam irradiation. The surface of the cryo fractured composite samples irradiated showed important visual changes which suggest a better fiber-matrix interfacial adhesion, due to irradiation treatment. These results showed that it is possible to get interesting property gains by using waste from renewable sources instead of the traditional ones and electron-beam radiation treatment. (author)

Chemotaxonomic Evaluation of Species of Turkish Salvia: Fatty Acid Composition of Seed Oils. II

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Turgut Kılıç

2007-05-01

Full Text Available Fatty acids composition of seed oil of Salvia viridis, S. hydrangea, S. blepharochleana, S. chianantha, S. staminea, S. hypergeia,, S. cilicica, S. caespitosa, S. sclarea, S. cadmica, S. microstegia, S. pachystachys and S. verticillata were analyzed by GC/MS. The main compound were found to be as linoleic acid (18:2; 12.8 % to 52.2 %, linolenic acid (18:3; 3.2 % to 47.7 %, oleic acid (18:1; 11.3 % to 25.6 %, palmitic acid (16:0; 0.7 % to 16.8 % and stearic acid (18:0; 1.8 % to 4.8 %. A phylogenetic tree of species of Salvia were reported and compared to 18:3/18:2 ratio of the seed oils. Fatty acid composition of Salvia seed oils could be used as a chemotaxonomical marker.

Automatic 1H-NMR Screening of Fatty Acid Composition in Edible Oils

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David Castejón

2016-02-01

Full Text Available In this work, we introduce an NMR-based screening method for the fatty acid composition analysis of edible oils. We describe the evaluation and optimization needed for the automated analysis of vegetable oils by low-field NMR to obtain the fatty acid composition (FAC. To achieve this, two scripts, which automatically analyze and interpret the spectral data, were developed. The objective of this work was to drive forward the automated analysis of the FAC by NMR. Due to the fact that this protocol can be carried out at low field and that the complete process from sample preparation to printing the report only takes about 3 min, this approach is promising to become a fundamental technique for high-throughput screening. To demonstrate the applicability of this method, the fatty acid composition of extra virgin olive oils from various Spanish olive varieties (arbequina, cornicabra, hojiblanca, manzanilla, and picual was determined by 1H-NMR spectroscopy according to this protocol.

Photoproducts of carminic acid formed by a composite from Manihot dulcis waste.

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Antonio-Cisneros, Cynthia M; Dávila-Jiménez, Martín M; Elizalde-González, María P; García-Díaz, Esmeralda

2015-04-15

Carbon-TiO2 composites were obtained from carbonised Manihot dulcis waste and TiO2 using glycerol as an additive and thermally treating the composites at 800 °C. Furthermore, carbon was obtained from manihot to study the adsorption, desorption and photocatalysis of carminic acid on these materials. Carminic acid, a natural dye extracted from cochineal insects, is a pollutant produced by the food industry and handicrafts. Its photocatalysis was observed under different atmospheres, and kinetic curves were measured by both UV-Vis and HPLC for comparison, yielding interesting differences. The composite was capable of decomposing approximately 50% of the carminic acid under various conditions. The reaction was monitored by UV-Vis spectroscopy and LC-ESI-(Qq)-TOF-MS-DAD, enabling the identification of some intermediate species. The deleterious compound anthracene-9,10-dione was detected both in N2 and air atmospheres. Copyright © 2014 Elsevier Ltd. All rights reserved.

Electron beam irradiation effects on carbon fiber reinforced PEEK composite

International Nuclear Information System (INIS)

Sasuga, Tsuneo; Hagiwara, Miyuki; Odajima, Tosikazu; Sakai, Hideo; Nakakura, Toshiyuki; Masutani, Masahiro.

1987-03-01

Carbon fiber(CF) reinforced composites, using polyarylether-sulfone (PES) or polyarylether-ether-ketone (PEEK) as matrix material, were prepared and their electron beam irradiation effects were studied on the basis of changes in mechanical and dynamic viscoelastic properties and observation of fracture surfaces. The flexural strength of PES-CF composite decreased to 70 % of the initial strength after the irradiation of 3 MGy and 40 % after 15 MGy. The change in the profile of stress-strain (S-S) curves and fractographic observation by electron microscopy indicated that this composite irradiated with over 3 MGy was fractured by delamination caused by to the degradation of matrix polymer. The mechanical properties of PEEK-CF composite were scarcely decreased even after irradiated up to 180 MGy and this composite showed very high radiation resistance. The change in the profile of S-S curves and fractographic observation showed that this composite fractured due to destruction of fiber in the dose range less than 180 MGy, indicating that PEEK was excellent matrix material used in high radiation field. PEEK-PES-CF composite which was composed of the carbon fibers coated with PES solution showed less radiation resistance compared with PEEK-CF composite; the flexural strength decreased to 85 % of the initial value after the irradiation with 90 MGy. It was revealed from the changes in the profile of S-S curve that the specimen irradiated over 120 MGy was fractured due to not only fiber destruction but delamination. Deterioration mechanism of PEEK-PES-CF composite was studied by dynamic viscoelastic measurements in connection with the damage on matrix-fiber interface. It was suggested that the deterioration in mechanical properties of this composite was caused by the degradation of PES that coated on the surface of the carbon fibers. (author)

Brittle and ductile adjustable cement derived from calcium phosphate cement/polyacrylic acid composites.

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Chen, Wen-Cheng; Ju, Chien-Ping; Wang, Jen-Chyan; Hung, Chun-Cheng; Chern Lin, Jiin-Huey

2008-12-01

Bone filler has been used over the years in dental and biomedical applications. The present work is to characterize a non-dispersive, fast setting, modulus adjustable, high bioresorbable composite bone cement derived from calcium phosphate-based cement combined with polymer and binding agents. This cement, we hope, will not swell in simulated body fluid and keep the osteogenetic properties of the dry bone and avoid its disadvantages of being brittle. We developed a calcium phosphate cement (CPC) of tetracalcium phosphate/dicalcium phosphate anhydrous (TTCP/DCPA)-polyacrylic acid with tartaric acid, calcium fluoride additives and phosphate hardening solution. The results show that while composite, the hard-brittle properties of 25wt% polyacrylic acid are proportional to CPC and mixing with additives is the same as those of the CPC without polyacrylic acid added. With an increase of polyacrylic acid/CPC ratio, the 67wt% samples revealed ductile-tough properties and 100wt% samples kept ductile or elastic properties after 24h of immersion. The modulus range of this development was from 200 to 2600MPa after getting immersed in simulated body fluid for 24h. The TTCP/DCPA-polyacrylic acid based CPC demonstrates adjustable brittle/ductile strength during setting and after immersion, and the final reaction products consist of high bioresorbable monetite/brushite/calcium fluoride composite with polyacrylic acid.

Study of the surface chemistry and morphology of single walled carbon nanotube-magnetite composites

International Nuclear Information System (INIS)

Marquez-Linares, F.; Uwakweh, O.N.C.; Lopez, N.; Chavez, E.; Polanco, R.; Morant, C.; Sanz, J.M.; Elizalde, E.; Neira, C.; Nieto, S.; Roque-Malherbe, R.

2011-01-01

The study of the morphologies of the single walled carbon nanotube (SWCNT), magnetite nanoparticles (MNP), and the composite based on them was carried with combined X-ray diffraction (XRD), Raman spectroscopy (RS), scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). These techniques together with thermogravimetric analyses (TGA) and diffuse reflectance infrared transform spectroscopy (DRIFTS) confirmed the production of pure single phases, and that the composite material consisted of MNP attached to the outer surface of the SWCNT. The Moessbauer spectroscopy (MS) research showed the presence of a large quantity of Lewis acid sites in the highly dispersed magnetite particles supported on the SWCNT outer surface. The DRIFTS carbon dioxide adsorption study of the composites revealed significant adsorption of carbon dioxide, fundamentally in the Lewis acid sites. Then, the Lewis acid sites were observed to be catalytically active. Further, the electron exchange between the Lewis acid sites and the basic or amphoteric adsorbed molecules could influence the magnetic properties of the magnetite. Consequently, together with this first ever use of MS in the study of Lewis acid sites, this investigation revealed the potential of the composites for catalytic and sensors applications. -- Graphical abstract: A large amount of Lewis acid sites were found in the highly dispersed magnetite which is supported on the SWCNT outer surface. Display Omitted Research highlights: → The obtained materials were completely characterized with XRD, Raman and SEM-TEM. → DRIFT, TGA and adsorption of the composites allowed understand the material formation. → This is the first report of a study of Lewis sites by Moessbauer spectroscopy.

Terahertz absorption in graphite nanoplatelets/polylactic acid composites

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Bychanok, D.; Angelova, P.; Paddubskaya, A.; Meisak, D.; Shashkova, L.; Demidenko, M.; Plyushch, A.; Ivanov, E.; Krastev, R.; Kotsilkova, R.; Ogrin, F. Y.; Kuzhir, P.

2018-04-01

The electromagnetic properties of composite materials based on poly(lactic) acid (PLA) filled with graphite nanoplatelets (GNP) were investigated in the microwave (26–37 GHz) and terahertz (0.2–1 THz) frequency ranges. The maximum of the imaginary part of the dielectric permittivity was observed close to 0.6 THz for composites with 1.5 and 3 wt.% of GNP. The experimental data of complex dielectric permittivity of GNP/PLA composites was modelled using the Maxwell-Garnett theory. The effects of fine dispersion, agglomeration, and percolation in GNP-based composites on its electromagnetic constitutive parameters, presence, and position of THz absorption peak are discussed on the basis of the modeling results and experimental data. The unique combination of conductive and geometrical parameters of GNP embedded into the PLA matrix below the percolation threshold allow us to obtain the THz-absorptive material, which may be effectively used as a 3D-printing filament.

Nutritional value and fatty acid composition of some traditional Argentinean meat sausages

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Mara Cristina Romero

2013-03-01

Full Text Available The aim of this study was to determine the nutritional composition (moisture, protein, carbohydrates, and total fat of some meat products produced in the northeastern Argentina, analyzing fatty acids composition, polyunsaturated/saturated fatty acid ratio PUFA/SFA ratio (polyunsaturated/ saturated fatty acids, n-6/n-3 ratio, and CLA (conjugated linoleic acid content. Thirty traditional meat products produced by different processes were used. The samples were classified into 4 different categories as follows: salamín (dry cured and fermented sausage, chorizos (raw sausage, chorizo ahumado (cooked and smoked sausage, and morcilla (cooked sausage. From the results obtained it can be said that the total carbohydrate contents of the salamín studied were slightly lower; fat content of raw chorizo was significantly lower, and protein content of chorizo ahumado was significantly higher than those comparison from databases from other regions of Argentina, USA, and Spain. Except for chorizo, which has a value lower than 0.4, the PUFA/SFA-stearic ratio of the other products were a little higher than those reported by other researchers. CLA (Conjugated linoleic acid contents between 0.03% and 0.19% were detected. The results obtained indicate that salamín produced in northeastern Argentina, Chaco state, shows high protein and PUFA (Polyunsaturated fatty acids contents, and low atherogenic and thrombogenic indexes, which makes it a more healthful product than those of similar composition produced in other countries.

Analysis of fatty acid composition of sea cucumber Apostichopus japonicus using multivariate statistics

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Xu, Qinzeng; Gao, Fei; Xu, Qiang; Yang, Hongsheng

2014-11-01

Fatty acids (FAs) provide energy and also can be used to trace trophic relationships among organisms. Sea cucumber Apostichopus japonicus goes into a state of aestivation during warm summer months. We examined fatty acid profiles in aestivated and non-aestivated A. japonicus using multivariate analyses (PERMANOVA, MDS, ANOSIM, and SIMPER). The results indicate that the fatty acid profiles of aestivated and non-aestivated sea cucumbers differed significantly. The FAs that were produced by bacteria and brown kelp contributed the most to the differences in the fatty acid composition of aestivated and nonaestivated sea cucumbers. Aestivated sea cucumbers may synthesize FAs from heterotrophic bacteria during early aestivation, and long chain FAs such as eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) that produced from intestinal degradation, are digested during deep aestivation. Specific changes in the fatty acid composition of A. japonicus during aestivation needs more detailed study in the future.

Composition and textural properties of Mozzarella cheese naturally-enriched in polyunsaturated fatty acids.

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Caroprese, Mariangela; Sevi, Agostino; Marino, Rosaria; Santillo, Antonella; Tateo, Alessandra; Albenzio, Marzia

2013-08-01

The effects of adding flaxseed or fish oil to the diet of dairy cows on the chemical and physical profile of Mozzarella cheese production were studied. The experiment involved 24 Friesian cows, divided into 3 groups accordingly fat supplementation: basal diet (CT), diet supplemented with flaxseed (FS) or fish oil (FO). Mozzarella cheeses were manufactured from bulk milk of each group. Bulk milk was analysed for chemical composition and renneting parameters. Mozzarella cheeses were analysed for chemical composition, fatty acid profile, and textural properties. Results suggest that Mozzarella cheese from cows receiving flaxseed supplementation showed a decrease in saturated fatty acids (SFA), an increase in monounsaturated fatty acids (MUFA), and in polyunsaturated fatty acids (PUFA) compared with control Mozzarella cheese. The increased dietary intake of C18:3 in flaxseed supplemented cows resulted in increased levels of trans-11 C18:1, and of CLA cis-9 trans-11 C18:2, and in low Atherogenic and Trombogenic Indexes. FO Mozzarella cheese showed compositional and textural properties quite similar to CT Mozzarella cheese; however, increased levels of n-3 polyunsaturated fatty acids in FO Mozzarella were found.

Fatty Acid Composition of Hibiscus trionum L. (Malvaceae

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Ceyda Sibel Kılıç

2011-01-01

Full Text Available The genus Hibiscus plants have different uses, some are used as foods (H. esculenta L., and some species as remedy in traditional medicine (H. sabdariffa L. as well as a colorant for herbal teas. The only species that grows naturally in Turkey is H. trionum L. The plant especially infests soy and corn fields, and therefore it is considered to be a noxious weed. The plant is also found to be a host for Potato Virus Y (PVY and Tomato Spotted Wilt Virus (TSWV. Infestation of the crop fields by this plant shows that it germinates easily. Since it produces many seeds, distribution of the plant is also quiet easy. Though, seed oil yield is low (4.7% since linoleic acid composition of the seed oil is quiet high (67,5%, it can still be used as a source of unsaturated fatty acids. The other major fatty acids are palmitic, oleic and stearic acids in the studied seed oil .

Evolutionary modifications of human milk composition: evidence from long-chain polyunsaturated fatty acid composition of anthropoid milks.

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Milligan, Lauren A; Bazinet, Richard P

2008-12-01

Brain growth in mammals is associated with increased accretion of long-chain polyunsaturated fatty acids (LCPUFA) in brain phospholipids. The period of maximum accumulation is during the brain growth spurt. Humans have a perinatal brain growth spurt, selectively accumulating docosahexaenoic acid (DHA) and other LCPUFA from the third trimester through the second year of life. The emphasis on rapid postnatal brain growth and LCPUFA transfer during lactation has led to the suggestion that human milk LCPUFA composition may be unique. Our study tests this hypothesis by determining fatty acid composition for 11 species of captive anthropoids (n=53; Callithrix jacchus, Cebus apella, Gorilla gorilla, Hylobates lar, Leontopithecus rosalia, Macaca mulatta, Pan troglodytes, Pan paniscus, Pongo pygmaeus, Saimiri boliviensis, and Symphalangus syndactylus). Results are compared to previously published data on five species of wild anthropoids (n=28; Alouatta paliatta, Callithrix jacchus, Gorilla beringei, Leontopithecus rosalia, and Macaca sinica) and human milk fatty acid profiles. Milk LCPUFA profiles of captive anthropoids (consuming diets with a preformed source of DHA) are similar to milk from women on a Western diet, and those of wild anthropoids are similar to milk from vegan women. Collectively, the range of DHA percent composition values from nonhuman anthropoid milks (0.03-1.1) is nearly identical to that from a cross-cultural analysis of human milk (0.06-1.4). Humans do not appear to be unique in their ability to secrete LCPUFA in milk but may be unique in their access to dietary LCPUFA.

Composition of fatty acids in selected vegetable oils

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Helena Frančáková

2015-12-01

Full Text Available Plant oils and fats are important and necessary components of the human nutrition. They are energy source and also contain fatty acids - compounds essential for human health. The aim of this study was to evaluate nutritional quality of selected plant oil - olive, rapeseed, pumpkin, flax and sesame; based on fatty acid composition in these oils. Fatty acids (MUFA, PUFA, SFA were analyzed chromatography using system Agilent 6890 GC, injector multimode, detector FID. The highest content of saturated fatty acids was observed in pumpkinseed oil (19.07%, the lowest content was found in rapeseed oil (7.03%, with low level of palmitic and stearic acids and high level of behenic acid (0.32% among the evaluated oils. The highest content of linoleic acid was determined in pumpkinseed (46.40% and sesame oil (40.49%; in these samples was also found lowest content of α-linolenic acid. These oils have important antioxidant properties and are not subject to oxidation. The richest source of linolenic acid was flaxseed oil which, which is therefore more difficult to preserve and process in food industry. In olive oil was confirmed that belongs to the group of oils with a predominantly monosaturated oleic acid (more than 70% and a small amount of polysaturated fatty acid. The most commonly used rapeseed oil belongs to the group of oils with the medium content of linolenic acid (8.76%; this oil also showed a high content of linoleic acid (20.24%. The group of these essentially fatty acids showed a suitable ratio ∑n3/n6 in the rapessed oil (0.44.

Photoperiod affects daily torpor and tissue fatty acid composition in deer mice

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Geiser, Fritz; McAllan, B. M.; Kenagy, G. J.; Hiebert, Sara M.

2007-04-01

Photoperiod and dietary lipids both influence thermal physiology and the pattern of torpor of heterothermic mammals. The aim of the present study was to test the hypothesis that photoperiod-induced physiological changes are linked to differences in tissue fatty acid composition of deer mice, Peromyscus maniculatus (˜18-g body mass). Deer mice were acclimated for >8 weeks to one of three photoperiods (LD, light/dark): LD 8:16 (short photoperiod), LD 12:12 (equinox photoperiod), and LD 16:8 (long photoperiod). Deer mice under short and equinox photoperiods showed a greater occurrence of torpor than those under long photoperiods (71, 70, and 14%, respectively). The duration of torpor bouts was longest in deer mice under short photoperiod (9.3 ± 2.6 h), intermediate under equinox photoperiod (5.1 ± 0.3 h), and shortest under long photoperiod (3.7 ± 0.6 h). Physiological differences in torpor use were associated with significant alterations of fatty acid composition in ˜50% of the major fatty acids from leg muscle total lipids, whereas white adipose tissue fatty acid composition showed fewer changes. Our results provide the first evidence that physiological changes due to photoperiod exposure do result in changes in lipid composition in the muscle tissue of deer mice and suggest that these may play a role in survival of low body temperature and metabolic rate during torpor, thus, enhancing favourable energy balance over the course of the winter.

Si/C composite lithium-ion battery anodes synthesized from coarse silicon and citric acid through combined ball milling and thermal pyrolysis

International Nuclear Information System (INIS)

Gu Peng; Cai Rui; Zhou Yingke; Shao Zongping

2010-01-01

Silicon and related materials have recently received considerable attention as potential anodes in Li-ion batteries for their high theoretical specific capacities. To overcome the problem of volume variations during the Li insertion/extraction process, in this work, Si/C composites with low carbon content were synthesized from cheap coarse silicon and citric acid by simple ball milling and subsequent thermal treatment. The effects of ball milling time and calcination temperature on the structure, composition and morphology of the composites were systematically investigated by the determination of specific surface area (BET) and particle-size distribution, X-ray diffraction (XRD), O 2 -TPO, and scanning electron microscopy (SEM). The capacity and cycling stability of the composites were systematically evaluated by electrochemical charge/discharge tests. It was found that both the initial capacity and the cycling stability of the composites were dependent on the milling and calcination conditions, and attractive overall electrochemical performance could be obtained by optimizing the synthesis process.

Sexually dimorphic brain fatty acid composition in low and high fat diet-fed mice.

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Rodriguez-Navas, Carlos; Morselli, Eugenia; Clegg, Deborah J

2016-08-01

In this study, we analyzed the fatty acid profile of brains and plasma from male and female mice fed chow or a western-style high fat diet (WD) for 16 weeks to determine if males and females process fatty acids differently. Based on the differences in fatty acids observed in vivo, we performed in vitro experiments on N43 hypothalamic neuronal cells to begin to elucidate how the fatty acid milieu may impact brain inflammation. Using a comprehensive mass spectrometry fatty acid analysis, which includes a profile for 52 different fatty acid isomers, we assayed the plasma and brain fatty acid composition of age-matched male and female mice maintained on chow or a WD. Additionally, using the same techniques, we determined the fatty acid composition of N43 hypothalamic cells following exposure to palmitic and linoleic acid, alone or in combination. Our data demonstrate there is a sexual dimorphism in brain fatty acid content both following the consumption of the chow diet, as well as the WD, with males having an increased percentage of saturated fatty acids and reductions in ω6-polyunsaturated fatty acids when compared to females. Interestingly, we did not observe a sexual dimorphism in fatty acid content in the plasma of the same mice. Furthermore, exposure of N43 cells to the ω6-PUFA linoleic acid, which is higher in female brains when compared to males, reduces palmitic acid-induced inflammation. Our data suggest male and female brains, and not plasma, differ in their fatty acid profile. This is the first time, to our knowledge, lipidomic analyses has been used to directly test the hypothesis there is a sexual dimorphism in brain and plasma fatty acid composition following consumption of the chow diet, as well as following exposure to the WD.

The effect of breed on fatty acid composition of subcutaneous ...

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2015-02-23

Agilent Auto Analyzer 7683 B series, Agilent Technologies, Santa Clara, Calif, USA) into ..... laboratory facilities and financial support. ... supplementation on fatty acid composition and gene expression in adipose tissue of growing ...

Combined electron microscopy and spectroscopy characterization of as-received, acid purified, and oxidized HiPCO single-wall carbon nanotubes

International Nuclear Information System (INIS)

Rosario-Castro, Belinda I.; Contes, Enid J.; Lebron-Colon, Marisabel; Meador, Michael A.; Sanchez-Pomales, Germarie; Cabrera, Carlos R.

2009-01-01

Single-wall carbon nanotubes (SWCNTs) are very important materials due to their combination of unique structure, dimension, strength, chemical stability, and electronic properties. Nevertheless, SWCNTs from commercial sources usually contain several impurities, which are usually removed by a purification process that includes reflux in acids and strong oxidation. This strong chemical procedure may alter the nanotube properties and it is thus important to control the extent of functionalization and oxidation during the purification procedure. In this report, we provide a comprehensive study of the structure and physical composition of SWCNTs during each step of the purification process. Techniques such as Raman spectroscopy, transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy and Infrared spectroscopy were used to track the SWCNTs structure, in terms of length and diameter distribution, and surface chemical modifications during each purification stage.

The relationship between fatty acid compositions and thermal stability of extra virgin olive oils

OpenAIRE

Fayegh Moulodi; Peyman Qajarbeigi; Ashraf Haj Hosseini Babaei; Asghar Mohammadpoor Asl

2014-01-01

Background: Fatty acids are one of the most important compounds in edible oils. Further, the stability of oils depends on the composition of fatty acids. So, this study was conducted to investigate the effect of fatty acid composition on the oxidative stability of extra virgin olive oils during the heating process. Methods: In total, eight samples of extra virgin olive oil were studied. To evaluate their thermal stability, the oils were heated at 120 ° C for 4 h and sampling was carried o...

Composite Fermi surface in the half-filled Landau level with anisotropic electron mass

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Ippoliti, Matteo; Geraedts, Scott; Bhatt, Ravindra

We study the problem of interacting electrons in the lowest Landau level at half filling in the quantum Hall regime, when the electron dispersion is given by an anisotropic mass tensor. Based on experimental observations and theoretical arguments, the ground state of the system is expected to consist of composite Fermions filling an elliptical Fermi sea, with the anisotropy of the ellipse determined by the competing effects of the isotropic Coulomb interaction and anisotropic electron mass tensor. We test this idea quantitatively by using a numerical density matrix renormalization group method for quantum Hall systems on an infinitely long cylinder. Singularities in the structure factor allow us to map the Fermi surface of the composite Fermions. We compute the composite Fermi surface anisotropy for several values of the electron mass anisotropy which allow us to deduce the functional dependence of the former on the latter. This research was supported by Department of Energy Office of Basic Energy Sciences through Grant No. DE-SC0002140.

Experimental Investigation and Analysis of Mercerized and Citric Acid Surface Treated Bamboo Fiber Reinforced Composite

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De, Jyotiraman; Baxi, R. N., Dr.

2017-08-01

Mercerization or NaOH fiber surface treatment is one of the most popular surface treatment processes to make the natural fibers such as bamboo fibers compatible for use as reinforcing material in composites. But NaOH being a chemical is hazardous and polluting to the nature. This paper explores the possibility of use of naturally derived citric acid for bamboo fiber surface treatment and its comparison with NaOH treated Bamboo Fiber Composites. Untreated, 2.5 wt% NaOH treated and 5 wt% citric acid treated Bamboo Fiber Composites with 5 wt% fiber content were developed by Hand Lay process. Bamboo mats made of bamboo slivers were used as reinforcing material. Mechanical and physical characterization was done to compare the effects of NaOH and citric acid bamboo fiber surface treatment on mechanical and physical properties of Bamboo Fiber Composite. The experiment data reveals that the tensile and flexural strength was found to be highest for citric acid and NaOH treated Bamboo Fiber Composite respectively. Water absorption tendency was found more than the NaOH treated Bamboo Fiber Composites. SEM micrographs used to analyze the morphology of fracture surface of tensile test specimens confirm improvement in fiber-matrix interface bonding due to surface treatment of bamboo fibers.

Seed oil and fatty acid composition in Capsicum spp

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The oil content and fatty acid composition of seed of 233 genebank accessions (total) of nine Capsicum species, and a single accession of Tubocapsicum anomalum, were determined. The physicochemical characteristics of oil extracted from seed of C. annuum and C. baccatum were also examined. Significan...

Preparation and properties of palmitic-stearic acid eutectic mixture/expanded graphite composite as phase change material for energy storage

International Nuclear Information System (INIS)

Zhang, Nan; Yuan, Yanping; Du, Yanxia; Cao, Xiaoling; Yuan, Yaguang

2014-01-01

A novel composite PCM (phase change material) with PA-SA (palmitic-stearic acid) eutectic mixture as PCM and EG (expanded graphite) as supporting material was prepared. The optimum absorption ratio of PA-SA/EG (Palmitic-stearic acid/expanded graphite) composite PCM was determined as PA-SA:EG = 13:1 (by mass). Scanning electron microscope and Fourier transformation infrared spectroscopy results show that PA-SA was uniformly distributed in the porous network structure of EG due to the physical action. Thermal property and thermal stability of the PA-SA/EG composite PCM were characterized by DSC (differential scanning calorimetry) and TGA (thermogravimetric analysis). DSC results indicated that the melting and freezing temperatures and latent heats of PA-SA/EG were measured as 53.89 °C and 54.37 °C, and 166.27 J/g and 166.13 J/g. TGA test results revealed that PA-SA/EG had a good thermal stability in working temperature range. Thermal cycling test results showed PA-SA/EG had a good thermal reliability after 720 thermal cycles. Thermal conductivity of the composite PCM was measured as 2.51 W/m K, much higher than that of PA-SA. The thermal energy storage and release rates of PA-SA/EG were also increased due to the high thermal conductivity of EG. In conclusion, the prepared PA-SA/EG composite PCM can be acted as a potential material for thermal energy storage due to the acceptable thermal properties, good thermal reliability and stability, high thermal conductivity. - Highlights: • PA-SA/EG (Palmitic-stearic acid/expanded graphite) composite PCM was prepared. • Optimum absorption ratio of PA-SA in EG was obtained as 13:1 (by mass). • Thermal conductivity and performance of PA-SA/EG have been significate improved. • PA-SA/EG has a good thermal reliability and thermal stability

Studies on the Electrical Properties of Graphene Oxide-Reinforced Poly (4-Styrene Sulfonic Acid) and Polyvinyl Alcohol Blend Composites

Science.gov (United States)

Deshmukh, Kalim; Sankaran, Sowmya; Basheer Ahamed, M.; Khadheer Pasha, S. K.; Sadasivuni, Kishor Kumar; Ponnamma, Deepalekshmi; Al-Ali Almaadeed, Mariam; Chidambaram, K.

In the present study, graphene oxide (GO)-reinforced poly (4-styrenesulfonic acid) (PSSA)/polyvinyl alcohol (PVA) blend composite films were prepared using colloidal blending technique at various concentrations of GO (0-3wt.%). The morphological investigations of the prepared composites were carried out using polarized optical microscopy and scanning electron microscopy. The electrical properties of composites were evaluated using an impedance analyzer in the frequency range 50Hz to 20MHz and temperature in the range 40-150∘C. Morphological studies infer that GO was homogeneously dispersed in the PSSA/PVA blend matrix. Investigations of electrical property indicate that the incorporation of GO into PSSA/PVA blend matrix resulted in the enhancement of the impedance (Z) and the quality factor (Q-factor) values. A maximum impedance of about 4.32×106Ω was observed at 50Hz and 90∘C for PSSA/PVA/GO composites with 3wt.% GO loading. The Q-factor also increased from 8.37 for PSSA/PVA blend to 59.8 for PSSA/PVA/GO composites with 3wt.% GO loading. These results indicate that PSSA/PVA/GO composites can be used for high-Q capacitor applications.

Hydroxycinnamic acids used as external acceptors of electrons: an energetic advantage for strictly heterofermentative lactic acid bacteria.

Science.gov (United States)

Filannino, Pasquale; Gobbetti, Marco; De Angelis, Maria; Di Cagno, Raffaella

2014-12-01

The metabolism of hydroxycinnamic acids by strictly heterofermentative lactic acid bacteria (19 strains) was investigated as a potential alternative energy route. Lactobacillus curvatus PE5 was the most tolerant to hydroxycinnamic acids, followed by strains of Weissella spp., Lactobacillus brevis, Lactobacillus fermentum, and Leuconostoc mesenteroides, for which the MIC values were the same. The highest sensitivity was found for Lactobacillus rossiae strains. During growth in MRS broth, lactic acid bacteria reduced caffeic, p-coumaric, and ferulic acids into dihydrocaffeic, phloretic, and dihydroferulic acids, respectively, or decarboxylated hydroxycinnamic acids into the corresponding vinyl derivatives and then reduced the latter compounds to ethyl compounds. Reductase activities mainly emerged, and the activities of selected strains were further investigated in chemically defined basal medium (CDM) under anaerobic conditions. The end products of carbon metabolism were quantified, as were the levels of intracellular ATP and the NAD(+)/NADH ratio. Electron and carbon balances and theoretical ATP/glucose yields were also estimated. When CDM was supplemented with hydroxycinnamic acids, the synthesis of ethanol decreased and the concentration of acetic acid increased. The levels of these metabolites reflected on the alcohol dehydrogenase and acetate kinase activities. Overall, some biochemical traits distinguished the common metabolism of strictly heterofermentative strains: main reductase activity toward hydroxycinnamic acids, a shift from alcohol dehydrogenase to acetate kinase activities, an increase in the NAD(+)/NADH ratio, and the accumulation of supplementary intracellular ATP. Taken together, the above-described metabolic responses suggest that strictly heterofermentative lactic acid bacteria mainly use hydroxycinnamic acids as external acceptors of electrons. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Dye sensitized solar cell of TiO{sub 2} nanoparticle/nanorod composites prepared via low-temperature synthesis in oleic acid

Energy Technology Data Exchange (ETDEWEB)

Saji, Viswanathan S. [Department of Printed Electronics Engineering, Sunchon National University, Chonnam 540-742 (Korea, Republic of); Pyo, Myoungho, E-mail: mho@sunchon.ac.k [Department of Printed Electronics Engineering, Sunchon National University, Chonnam 540-742 (Korea, Republic of)

2010-09-01

Titania (TiO{sub 2}) nanorods (NRs) and nanoparticles (NPs) were synthesized using oleic acid as a surfactant and employed as photoanodes for dye sensitized solar cell (DSSC) fabrication. The synthesized NRs and NPs were characterized using transmission electron microscopy and X-ray diffraction. The photovoltaic performances were compared between NRs, NPs, and their composites. The results showed that the power conversion efficiencies ({eta}) of the composites depend on the relative compositions of NRs and NPs in photoanodes, reaching the greatest at 10% NR content. {eta} of the pure NRs DSSC was lower than that of the NPs DSSC. Electrochemical impedance spectroscopy revealed that the highest {eta} at 10% NRs is mainly due to reduced charge transport resistance at the TiO{sub 2}/dye/electrolyte interface and electrolyte diffusion resistance, overcoming the reduction of the number of adsorbed dye molecules.

Application of electron-chemical curing in the production of thin composite materials

International Nuclear Information System (INIS)

Kopetchenov, V.; Shik, V.; Konev, V.; Kurapov, A.; Misin, I.; Gavrilov, V.; Malik, V.

1993-01-01

Thousands of tons of various thin composite materials in rolls for electrotechnical and domestic application including a whole range of electrical insulating materials, such as varnished and polymer fabrics, glass-micatapes, prepregs, thin laminated plastics and clad laminates, materials for decorative and domestic purposes - pressure sensitive adhesive tape and laminates, covering and finishing compositions based on fabrics, films and papers are produced. An important advantage of the electron-chemical processing in the production of composite materials is an essential energy saving (reduction of energy consumption 3-5 times). Absence of the organic diluents in binders decreases fire and explosion hazards of the production and sufficiently decreases danger for the environment of the technology used. Research and Production Company ''Polyrad'' is engaged in the development of technologies and equipment for the production of thin composite materials by the Electron-Chemical Method. (author)

THE ROLE OF BACTERIAL SYMBIONTS IN AMINO ACID COMPOSITION OF BLACK BEAN APHIDS

Institute of Scientific and Technical Information of China (English)

MingGan; De-ChengDing; Xue-xiaMiao

2003-01-01

To evaluate the role of bacterial symbionts ( Buchnera spp. ) in the black bean aphids ( Aphis craccivora Koch), the aphids were treated with the antibiotic, rifampicin, to eliminate their intracellular symbiotic bacteria. Analysis of protein and amino acid concentration in 7-day-old of aposymbiotic aphids showed that the total protein content per mg fresh weight was significantly reduced by 29 %, but free amino acid titers were increased by 17% . The ratio of the essential amino acids was in general only around 20% essential amino acids in phloem sap of broad bean, whereas it was 44% and 37% in symbiotic and aposymbiotic aphids, respectively,suggesting that the composition of the free amino acids was unbalanced. For example, the essential amino acid,threonine represented 21. 6% of essential amino acids in symbiotic aphids, but it was only 16.7% in aposymbiotic aphids. Likewise, two nonessential amino acids, tyrosine and serine, represented 8.9% and 5.6% of total amino acids in symbiontic aphids, respectively, but they enhanced to 21.1% and 13.6% in aposymbiotic aphids. It seems likely that the elevated free amino acid concentration in aposymbiotic aphids was caused by the limited protein anabolism as the result of the unbalanced amino acid composition.

Fatty acids composition of Spanish black (Morus nigra L.) and white (Morus alba L.) mulberries.

Science.gov (United States)

Sánchez-Salcedo, Eva M; Sendra, Esther; Carbonell-Barrachina, Ángel A; Martínez, Juan José; Hernández, Francisca

2016-01-01

This research has determined qualitatively and quantitatively the fatty acids composition of white (Morus alba) and black (Morus nigra) fruits grown in Spain, in 2013 and 2014. Four clones of each species were studied. Fourteen fatty acids were identified and quantified in mulberry fruits. The most abundant fatty acids were linoleic (C18:2), palmitic (C16:0), oleic (C18:1), and stearic (C18:0) acids in both species. The main fatty acid in all clones was linoleic (C18:2), that ranged from 69.66% (MN2) to 78.02% (MA1) of the total fatty acid content; consequently Spanish mulberry fruits were found to be rich in linoleic acid, which is an essential fatty acid. The fatty acid composition of mulberries highlights the nutritional and health benefits of their consumption. Copyright © 2015 Elsevier Ltd. All rights reserved.

Carbon composite micro- and nano-tubes-based electrodes for detection of nucleic acids

Directory of Open Access Journals (Sweden)

Huska Dalibor

2011-01-01

Full Text Available Abstract The first aim of this study was to fabricate vertically aligned multiwalled carbon nanotubes (MWCNTs. MWCNTs were successfully prepared by using plasma enhanced chemical vapour deposition. Further, three carbon composite electrodes with different content of carbon particles with various shapes and sizes were prepared and tested on measuring of nucleic acids. The dependences of adenine peak height on the concentration of nucleic acid sample were measured. Carbon composite electrode prepared from a mixture of glassy and spherical carbon powder and MWCNTs had the highest sensitivity to nucleic acids. Other interesting result is the fact that we were able to distinguish signals for all bases using this electrode.

Essential fatty acid composition and correlates in children with severe acute malnutrition

DEFF Research Database (Denmark)

Babirekere-Iriso, Esther; Lauritzen, Lotte; Mortensen, Charlotte Gylling

2016-01-01

Background: Severe acute malnutrition (SAM) is a common condition in children living in low-income countries and may be associated with reduced polyunsaturated fatty acids (PUFA) blood levels. The purpose of this study was to describe whole blood fatty acid composition and correlates of PUFA...

Chemical composition and ruminal degradation kinetics of crude protein and amino acids, and intestinal digestibility of amino acids from tropical forages

Directory of Open Access Journals (Sweden)

Lidia Ferreira Miranda

2012-03-01

Full Text Available The objective of this research was to determine the chemical composition and ruminal degradation of the crude protein (CP, total and individual amino acids of leaves from tropical forages: perennial soybean (Neonotonia wightii, cassava (Manihot esculenta, leucaena (Leucaena leucocephala and ramie (Boehmeria nivea, and to estimate the intestinal digestibility of the rumen undegradable protein (RUDP and individual amino acids of leaves from the tropical forages above cited, but including pigeon pea (Cajanus cajan. Three nonlactating Holstein cows were used to determine the in situ ruminal degradability of protein and amino acids from leaves (6, 18 and 48 hours of ruminal incubation. For determination of the intestinal digestibility of RUDP, the residue from ruminal incubation of the materials was used for 18 hours. A larger concentration of total amino acids for ramie and smaller for perennial soybean were observed; however, they were very similar in leucaena and cassava. Leucine was the essential amino acid of greater concentration, with the exception of cassava, which exhibited a leucine concentration 40.45% smaller. Ramie showed 14.35 and 22.31% more lysine and methionine, respectively. The intestinal digestibility of RUDP varied from 23.56; 47.87; 23.48; 25.69 and 10.86% for leucaena, perennial soybean, cassava, ramie and pigeon pea, respectively. The individual amino acids of tropical forage disappeared in different extensions in the rumen. For the correct evaluation of those forages, one should consider their composition of amino acids, degradations and intestinal digestibility, once the amino acid composition of the forage does not reflect the amino acid profiles that arrived in the small intestine. Differences between the degradation curves of CP and amino acids indicate that degradation of amino acids cannot be estimated through the degradation curve of CP, and that amino acids are not degraded in a similar degradation profile.

Metabolism of Fructophilic Lactic Acid Bacteria Isolated from the Apis mellifera L. Bee Gut: Phenolic Acids as External Electron Acceptors

Science.gov (United States)

Filannino, Pasquale; Addante, Rocco; Pontonio, Erica; Gobbetti, Marco

2016-01-01

ABSTRACT Fructophilic lactic acid bacteria (FLAB) are strongly associated with the gastrointestinal tracts (GITs) of Apis mellifera L. worker bees due to the consumption of fructose as a major carbohydrate. Seventy-seven presumptive lactic acid bacteria (LAB) were isolated from GITs of healthy A. mellifera L. adults, which were collected from 5 different geographical locations of the Apulia region of Italy. Almost all of the isolates showed fructophilic tendencies: these isolates were identified as Lactobacillus kunkeei (69%) or Fructobacillus fructosus (31%). A high-throughput phenotypic microarray targeting 190 carbon sources was used to determine that 83 compounds were differentially consumed. Phenotyping grouped the strains into two clusters, reflecting growth performance. The utilization of phenolic acids, such as p-coumaric, caffeic, syringic, or gallic acids, as electron acceptors was investigated in fructose-based medium. Almost all FLAB strains showed tolerance to high phenolic acid concentrations. p-Coumaric acid and caffeic acid were consumed by all FLAB strains through reductases or decarboxylases. Syringic and gallic acids were partially metabolized. The data collected suggest that FLAB require external electron acceptors to regenerate NADH. The use of phenolic acids as external electron acceptors by the 4 FLAB showing the highest phenolic acid reductase activity was investigated in glucose-based medium supplemented with p-coumaric acid. Metabolic responses observed through a phenotypic microarray suggested that FLAB may use p-coumaric acid as an external electron acceptor, enhancing glucose dissimilation but less efficiently than other external acceptors such as fructose or pyruvic acid. IMPORTANCE Fructophilic lactic acid bacteria (FLAB) remain to be fully explored. This study intends to link unique biochemical features of FLAB with their habitat. The quite unique FLAB phenome within the group lactic acid bacteria (LAB) may have practical relevance

Amino acid compositional shifts during streptophyte transitions to terrestrial habitats.

Science.gov (United States)

Jobson, Richard W; Qiu, Yin-Long

2011-02-01

Across the streptophyte lineage, which includes charophycean algae and embryophytic plants, there have been at least four independent transitions to the terrestrial habitat. One of these involved the evolution of embryophytes (bryophytes and tracheophytes) from a charophycean ancestor, while others involved the earliest branching lineages, containing the monotypic genera Mesostigma and Chlorokybus, and within the Klebsormidiales and Zygnematales lineages. To overcome heat, water stress, and increased exposure to ultraviolet radiation, which must have accompanied these transitions, adaptive mechanisms would have been required. During periods of dehydration and/or desiccation, proteomes struggle to maintain adequate cytoplasmic solute concentrations. The increased usage of charged amino acids (DEHKR) may be one way of maintaining protein hydration, while increased use of aromatic residues (FHWY) protects proteins and nucleic acids by absorbing damaging UV, with both groups of residues thought to be important for the stabilization of protein structures. To test these hypotheses we examined amino acid sequences of orthologous proteins representing both mitochondrion- and plastid-encoded proteomes across streptophytic lineages. We compared relative differences within categories of amino acid residues and found consistent patterns of amino acid compositional fluxuation in extra-membranous regions that correspond with episodes of terrestrialization: positive change in usage frequency for residues with charged side-chains, and aromatic residues of the light-capturing chloroplast proteomes. We also found a general decrease in the usage frequency of hydrophobic, aliphatic, and small residues. These results suggest that amino acid compositional shifts in extra-membrane regions of plastid and mitochondrial proteins may represent biochemical adaptations that allowed green plants to colonize the land.

Assessment of oil content and fatty acid composition variability in two economically important Hibiscus species.

Science.gov (United States)

Wang, Ming Li; Morris, Brad; Tonnis, Brandon; Davis, Jerry; Pederson, Gary A

2012-07-04

The Hibiscus genus encompasses more than 300 species, but kenaf (Hibiscus cannabinus L.) and roselle (Hibiscus sabdariffa L.) are the two most economically important species within the genus. Seeds from these two Hibiscus species contain a relatively high amount of oil with two unusual fatty acids: dihydrosterculic and vernolic acids. The fatty acid composition in the oil can directly affect oil quality and its utilization. However, the variability in oil content and fatty acid composition for these two species is unclear. For these two species, 329 available accessions were acquired from the USDA germplasm collection. Their oil content and fatty acid composition were determined by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Using NMR and GC analyses, we found that Hibiscus seeds on average contained 18% oil and seed oil was composed of six major fatty acids (each >1%) and seven minor fatty acids (each Hibiscus cannabinus seeds contained significantly higher amounts of oil (18.14%), palmitic (20.75%), oleic (28.91%), vernolic acids (VA, 4.16%), and significantly lower amounts of stearic (3.96%), linoleic (39.49%), and dihydrosterculic acids (DHSA, 1.08%) than H. sabdariffa seeds (17.35%, 18.52%, 25.16%, 3.52%, 4.31%, 44.72%, and 1.57%, respectively). For edible oils, a higher oleic/linoleic (O/L) ratio and lower level of DHSA are preferred, and for industrial oils a high level of VA is preferred. Our results indicate that seeds from H. cannabinus may be of higher quality than H. sabdariffa seeds for these reasons. Significant variability in oil content and major fatty acids was also detected within both species. The variability in oil content and fatty acid composition revealed from this study will be useful for exploring seed utilization and developing new cultivars in these Hibiscus species.

Leaching of Electronic Waste Using Biometabolised Acids

Institute of Scientific and Technical Information of China (English)

M. Saidan; B. Brown; M. Valix

2012-01-01

The revolution in information and communication technology has brought huge technical benefits and wealth, but has created a major global problem： the generation of vast amounts of electronic waste, or e-waste through product obsolesce. The challenge in managing e-waste will be in developing sustainable recycling tech- nologies that are able to address the volume and complexity of this waste using cost effective and ecologically sen-sitive methods. In this study, the capability or microorganism metabolic acids in dissolving the metallic tractions from waste printed circuit boards was examined. Several factors were considered in the examination of the activityof the acids-including secondary reactions, solution pH, temperature and the nature of ligands in solutions （or bioacid constituents）. The leaching tests were cgnducted ex-situ, using synthetic organic acids. Leaching was performed for periods of up to 6 hat 70-90 ℃ and 1000 r-min-1.

Sexually dimorphic brain fatty acid composition in low and high fat diet-fed mice

Directory of Open Access Journals (Sweden)

Carlos Rodriguez-Navas

2016-08-01

Full Text Available Objective: In this study, we analyzed the fatty acid profile of brains and plasma from male and female mice fed chow or a western-style high fat diet (WD for 16 weeks to determine if males and females process fatty acids differently. Based on the differences in fatty acids observed in vivo, we performed in vitro experiments on N43 hypothalamic neuronal cells to begin to elucidate how the fatty acid milieu may impact brain inflammation. Methods: Using a comprehensive mass spectrometry fatty acid analysis, which includes a profile for 52 different fatty acid isomers, we assayed the plasma and brain fatty acid composition of age-matched male and female mice maintained on chow or a WD. Additionally, using the same techniques, we determined the fatty acid composition of N43 hypothalamic cells following exposure to palmitic and linoleic acid, alone or in combination. Results: Our data demonstrate there is a sexual dimorphism in brain fatty acid content both following the consumption of the chow diet, as well as the WD, with males having an increased percentage of saturated fatty acids and reductions in ω6-polyunsaturated fatty acids when compared to females. Interestingly, we did not observe a sexual dimorphism in fatty acid content in the plasma of the same mice. Furthermore, exposure of N43 cells to the ω6-PUFA linoleic acid, which is higher in female brains when compared to males, reduces palmitic acid-induced inflammation. Conclusions: Our data suggest male and female brains, and not plasma, differ in their fatty acid profile. This is the first time, to our knowledge, lipidomic analyses has been used to directly test the hypothesis there is a sexual dimorphism in brain and plasma fatty acid composition following consumption of the chow diet, as well as following exposure to the WD. Keywords: Obesity, N43, Palmitic acid, Linoleic acid, Central nervous system, Western diet, ω6-fatty acids

Studies on possibilities of polymer composites with conductive nanomaterials application in wearable electronics

Science.gov (United States)

Gralczyk, Kinga; Janczak, D.; Dybowska-Sarapuk, Ł.; Lepak, S.; Wróblewski, G.; Jakubowska, M.

2017-08-01

In the last few years there has been a growing interest in wearable electronic products, which are generating considerable interest especially in sport and medical industries. But rigid electronics is not comfortable to wear, so things like stretchable substrates, interconnects and electronic devices might help. Flexible electronics could adjust to the curves of a human body and allow the users to move freely. The objective of this paper is to study possibilities of polymer composites with conductive nanomaterials application in wearable electronics. Pastes with graphene, silver nanoplates and carbon nanotubes were manufactured and then interconnects were screen-printed on the surfaces of polyethylene terephthalate (PET) and fabric. Afterwards, the resistance and mechanical properties of samples were examined, also after washing them in a washing machine. It has been found that the best material for the conductive phase is silver. Traces printed directly on the fabric using conductive composites with one functional phase (silver nanoplates or graphene or carbon nanotubes) are too fragile to use them as a common solution in wearable electronics. Mechanical properties can be improved not only by adding carbon nanotubes or graphene to the silver paste, but also by printing additional layer of graphene paste or carbon nanotube paste onto silver layer. In fact, these solutions are not sufficient enough to solve a problem of using these composites in wearable electronics.

Fatty acid composition and desaturase gene expression in flax (Linum usitatissimum L.).

Science.gov (United States)

Thambugala, Dinushika; Cloutier, Sylvie

2014-11-01

Little is known about the relationship between expression levels of fatty acid desaturase genes during seed development and fatty acid (FA) composition in flax. In the present study, we looked at promoter structural variations of six FA desaturase genes and their relative expression throughout seed development. Computational analysis of the nucleotide sequences of the sad1, sad2, fad2a, fad2b, fad3a and fad3b promoters showed several basic transcriptional elements including CAAT and TATA boxes, and several putative target-binding sites for transcription factors, which have been reported to be involved in the regulation of lipid metabolism. Using semi-quantitative reverse transcriptase PCR, the expression patterns throughout seed development of the six FA desaturase genes were measured in six flax genotypes that differed for FA composition but that carried the same desaturase isoforms. FA composition data were determined by phenotyping the field grown genotypes over four years in two environments. All six genes displayed a bell-shaped pattern of expression peaking at 20 or 24 days after anthesis. Sad2 was the most highly expressed. The expression of all six desaturase genes did not differ significantly between genotypes (P = 0.1400), hence there were no correlations between FA desaturase gene expression and variations in FA composition in relatively low, intermediate and high linolenic acid genotypes expressing identical isoforms for all six desaturases. These results provide further clues towards understanding the genetic factors responsible for FA composition in flax.

Unsaturated polyester resin composition curable with ionizing radiations

International Nuclear Information System (INIS)

Maruyama, Tsutomu; Murata, Koichiro.

1971-01-01

An unsaturated polyester resin composition curable with ionizing radiations and excellent in weather resistance is provided. The composition is obtained by reacting 10-12 moles of a polyhydric alcohol (e.g. ethylene glycol) with 10 moles of an acid mixture (25.45% by mole of endo-cis-bicyclo (2,2,1)-5-heptene-2-3-dicarboxylic acid (A), 20-40% of unsaturated dibasic acid and 15-55% of saturated dibasic acid) so that the acid value reaches 4-11. The composition is useful as coating, laminating and molding materials. As a coating material it is excellent in surface hardening property. The ionizing radiation used is preferably β-, α-rays or electron beams. In one example, and unsaturated polyester was prepared by reacting 3 moles of fumaric acid, 2 moles of phthalic anhydride, 3 moles of adipic acid 3, moles of (A), 10 moles of neopentyl glycol and 1 mole of trimethylolpropane. The resin was dissolved into a mixture of styrene, methyl methacrylate and butyl acrylate (50:8:42) and incorporated with titanium white. An ABS plate was coated with the enamel thus obtained and irradiated with electron beams (12 Mrad). In exposure test at 60 0 C, luster of the film was 92 before exposure and 83 after 30 months. In a comparative run in which (A) was not used, luster of the film decreased from 90 to 45 in 30 months. (Sakaichi, S.)

Amiata donkeys: fat globule characteristics, milk gross composition and fatty acids

Directory of Open Access Journals (Sweden)

Mina Martini

2014-02-01

Full Text Available Amiata donkeys are a native breed reared in central Italy. Safeguarding native donkey breeds represents an opportunity for the development of marginal areas, especially given that donkey milk is now appearing on the market due to its potential benefits for human health. To date, only a few studies have focused on the characteristics of the milk fat globules (MFGs in the donkey species. The aim of this study was to assess the morphometric characteristics of the fat globules, gross composition and fatty acid classes in milk from Amiata donkeys reared according to the typical farming and feeding systems of the area of origin. Individual milk samples, collected from 28 Amiata donkeys between 90 and 150 days of lactation, showed the following average composition (g/100 mL: 9.47 dry matter, 1.63 protein, 0.78 casein, 0.53 fat, 7.12 lactose, and 0.36 ash. The unsaturated:saturated fatty acids ratio in milk was close to 1. The percentage of short chains was 12.29, and the percentage of long chain fatty acids was 47.64. The donkey MFGs showed an average diameter of 1.92 μm, and a number of 2.18*109/mL. Regarding MFG distribution, 70% of the globules donkey of milk are smaller than 2 μm. In conclusion, the gross composition and fatty acids of Amiata donkey milk showed similarities with milk from other Italian donkey breeds, with the exception of the monounsaturated fatty acid values which were slightly higher. Donkey MFGs had a smaller diameter and were fewer than in the ruminant species.

Radiation damage of proteins in the solid state: changes of amino acid composition in catalase

International Nuclear Information System (INIS)

Baumeister, W.; Hahn, M.; Seredynski, J.; Herbertz, L.M.

1976-01-01

Catalase has been irradiated with 100 keV electrons under conditions simulating the hazards of electron microscopic imaging. Amino acid analysis reveals a definite pattern of amino acid destruction which is well correlated with the particular chemical structures of amino acid side chains. This pattern appears to be distinctly different from the sensitivity pattern for monoamino acid systems which is ascribed to intramolecular energy transfer and selective attack of liberated radicals

Mapping QTL for fatty acid composition that segregates between the ...

African Journals Online (AJOL)

Mapping QTL for fatty acid composition that segregates between the Japanese Black and Limousin cattle breeds (Short communication). NOM Tshipuliso, LJ Alexander, TW Geary, VM Snelling, DC Rule, JE Koltes, BE Mote, MD MacNeil ...

Poly(3-hexylthiophene): Functionalized single-walled carbon nanotubes: (6,6)-phenyl-C{sub 61}-butyric acid methyl ester composites for photovoltaic cell at ambient condition

Energy Technology Data Exchange (ETDEWEB)

Singh, Rajiv K.; Kumar, Amit; Kumar, Vikram; Singh, Ramadhar [National Physical Laboratory (Council of Scientific and Industrial Research), Dr. K.S. Krishnan Marg, New Delhi 110012 (India); Kumar, Jitendra [Metals and Ceramics Division, University of Dayton Research Institute, Dayton, OH 45469-0171 (United States); Kant, Rama [Department of Chemistry, University of Delhi, New Delhi 110007 (India)

2010-12-15

We report the synthesis and characterization of nonhygroscopic composites of poly(3-hexylthiophene):functionalized single-walled carbon nanotubes:(6,6)-phenyl-C{sub 61}-butyric acid methyl ester (P3HT:FSWCNT:PCBM) for photovoltaic applications. The composite films have been characterized for their structural, electronic, photo-physical and photovoltaic properties. Fourier transform infrared (FT-IR) investigation suggests that the nanotubes can induce structural changes in P3HT matrix. The homogeneous dispersion of nanotubes in P3HT and its self-arranged matrix in P3HT:PCBM are evident from scanning electron microscopy (SEM). Ultraviolet-visible (UV-vis) spectrum indicates the betterment of P3HT chain stacking by addition of nanotubes, which is further confirmed by transmission electron microscopy (TEM). The small-angle X-ray scattering (SAXS) was used to determine the bulk microstructure of the polymer composite. The photovoltaic cells have been fabricated using the aforementioned photoactive composite and tested at ambient conditions. The comparison of the current density-voltage (J-V) characteristics of photovoltaic cells in light and dark conditions, with and without modified nanotubes, shows that the latter gives better photovoltaic properties. A photovoltaic cell using modified nanotubes exhibit a photo-conversion efficiency of {proportional_to}1.8%. The addition of FSWCNT in P3HT:PCBM composite enhances the conjugation length of P3HT:FSWCNT:PCBM composite, which in turn enhances its absorption capacity of solar energy radiation. (author)

Application of electron-chemical curing in the production of thin composite materials

Energy Technology Data Exchange (ETDEWEB)

Kopetchenov, V.; Shik, V.; Konev, V.; Kurapov, A.; Misin, I.; Gavrilov, V.; Malik, V. (Polyrad Research and Production Co., Moscow (Russian Federation))

Thousands of tons of various thin composite materials in rolls for electrotechnical and domestic application including a whole range of electrical insulating materials, such as varnished and polymer fabrics, glass-micatapes, prepregs, thin laminated plastics and clad laminates, materials for decorative and domestic purposes - pressure sensitive adhesive tape and laminates, covering and finishing compositions based on fabrics, films and papers are produced. An important advantage of the electron-chemical processing in the production of composite materials is an essential energy saving (reduction of energy consumption 3-5 times). Absence of the organic diluents in binders decreases fire and explosion hazards of the production and sufficiently decreases danger for the environment of the technology used. Research and Production Company ''Polyrad'' is engaged in the development of technologies and equipment for the production of thin composite materials by the Electron-Chemical Method. (author).

FATTY ACID COMPOSITION AND PROSTAGLANDIN CONTENT OF THE RED SEAWEED Gracilaria sp. FROM INDONESIA

Directory of Open Access Journals (Sweden)

Muhammad Ikbal Illijas

2012-06-01

Full Text Available High content of polyunsaturated fatty acids (PUFAs such as arachidonic and eicosapentaenoic acids are typical for the red alga. Analysis of fatty acid composition and prostaglandin content was conducted in the red alga Gracilaria sp. from Indonesia. Total lipid of the alga was extracted with CHCl3-MeOH (2:1, v/v. Analysis of the fatty acids composition was performed on gas chromatography (GC equipped with omega wax column (30 m x 0,32 mm i.d., Supelco, PA, USA and analysis of prostaglandins were carried out by HPLC on ODS column (Mightysil RP-18 GP, 250 mm x 4.6 mm, 5 μm. The content of fatty acids high for were palmitic acid (50% and arachidonic acid (26.9%, whereas prostaglandin E2 was identified and found lower concentration (44.2 μg/gram total lipid.

Fatty acid composition of the pollen lipids of Cycas revoluta Thunb

International Nuclear Information System (INIS)

Sidorov, R.A.; Kuznetsova, E.I.; Pchelkin, V.P.; Zhukov, A.V.; Gorshkova, E.N.; Tsydendambaev, V.D.

2016-01-01

The fatty acid (FA) composition of total extractable and non extractable with chloroform lipids of C. revoluta pollen was determined. Among other minor FAs, unusual Δ5 polymethylene-interrupted FA, Δ5, 11-octadecadienoic acid was found. This FA was found in the seed lipids of C. revoluta earlier, but it was discovered for the first time in pollen lipids. [es

Preparation and analysis of multilayer composites based on polyelectrolyte complexes

Energy Technology Data Exchange (ETDEWEB)

Petrova, V. A. [Russian Academy of Sciences, Institute of Macromolecular Compounds (Russian Federation); Orekhov, A. S. [Russian Academy of Sciences, Shubnikov Institute of Crystallography, Federal Scientific Research Centre “Crystallography and Photonics” (Russian Federation); Chernyakov, D. D. [St. Petersburg State Chemical Pharmaceutical Academy (Russian Federation); Baklagina, Yu. G. [Russian Academy of Sciences, Institute of Macromolecular Compounds (Russian Federation); Romanov, D. P. [Russian Academy of Sciences, Grebenshchikov Institute of Silicate Chemistry (Russian Federation); Kononova, S. V. [Russian Academy of Sciences, Institute of Macromolecular Compounds (Russian Federation); Volod’ko, A. V.; Ermak, I. M. [Russian Academy of Sciences, Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch (Russian Federation); Klechkovskaya, V. V., E-mail: klechvv@ns.crys.ras.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography, Federal Scientific Research Centre “Crystallography and Photonics” (Russian Federation); Skorik, Yu. A., E-mail: yury-skorik@mail.ru [Russian Academy of Sciences, Institute of Macromolecular Compounds (Russian Federation)

2016-11-15

A method for preparing multilayer film composites based on chitosan has been developed by the example of polymer pairs: chitosan–hyaluronic acid, chitosan–alginic acid, and chitosan–carrageenan. The structure of the composite films is characterized by X-ray diffractometry and scanning electron microscopy. It is shown that the deposition of a solution of hyaluronic acid, alginic acid, or carrageenan on a chitosan gel film leads to the formation of a polyelectrolyte complex layer at the interface, which is accompanied by the ordering of chitosan chains in the surface region; the microstructure of this layer depends on the nature of contacting polymer pairs.

Eccentric contractions affect muscle membrane phospholipid fatty acid composition in rats

DEFF Research Database (Denmark)

Helge, Jørn Wulff; Therkildsen, K J; Jørgensen, T B

2001-01-01

This study investigated if prior eccentric contractions, and thus mechanical strain and muscle damage, exert an effect on the muscle membrane phospholipid fatty acid composition in rats, and whether a possible effect could be attenuated by dietary supplements. Twenty-three rats were randomised...... muscle, was excised from both legs. In the muscles stimulated to contract eccentrically, compared to the control muscles, the proportion of arachidonic acid, C20:4,n-6 (17.7 +/- 0.6; 16.4 +/- 0.4% of total fatty acids, respectively) and docosapentanoeic acid, C22:5,n-3 (2.9 +/- 0.1 and 2.7 +/- 0.......1% of total fatty acids, respectively) was uniformly higher across groups (P fatty acids) compared to the control leg (38.2 +/- 0...

The effect of ionizing radiation on the fatty acid composition of natural fats and on lipid peroxide formation

International Nuclear Information System (INIS)

Hammer, C.T.; Wills, E.D.

1979-01-01

The effects of irradiation doses of 200 to 1000 krad on the fatty acid composition of saturated and unsaturated natural food fats have been studied. Lard, coconut oil, corn oil, methyl linoleate and herring oil have been analysed before and after irradiation for lipid peroxide content and fatty acid composition. The effects of storage under varied conditions after irradiation have also been investigated. Irradiation doses of 200 to 1000 krad had little effect on the fatty acid compositions of saturated fats (lard and coconut oil) or of fats with a high antioxidant content (corn oil) but caused destruction of 98 per cent of the highly unsaturated acids (18:4, 20:5, 22:6) and 46 per cent of the diene acids (18:2) in herring oil. The destruction of the polyunsaturated fatty acids increased with increasing storage temperature and storage time. The destruction of polyunsaturated fatty acids was accompanied by an increase in lipid peroxide formation. It is considered that changes in fatty acid composition in natural foods after irradiation are important in consideration of the use of irradiation of food preservation. (author)

Gelatin/piassava composites treated by Electron Beam Radiation

International Nuclear Information System (INIS)

Takinami, Patricia Yoko Inamura; Shimazaki, Kleber; Moura, Esperidiana Augusta Barretos de; Mastro, Nelida Lucia del; Colombo, Maria Aparecida

2010-01-01

Piassava (Attalea funifera Mart) fiber has been investigated as reinforcement for polymer composites with potential for practical applications. The purpose of the present work was to assess the behavior of specimens of piassava fiber and gelatin irradiated with electron beam at different doses and percentage. The piassava/gelatin specimens were made with 5 and 10% (w/w) piassava fiber, gelatin 25% (w/w), glycerin as plasticizer and acrylamide as copolymer. The samples were irradiated up to 40 kGy using an electron beam accelerator, at room temperature in presence of air. Preliminary results showed mechanical properties enhancement with the increase in radiation dose. (author)

A medicated polycarboxylate cement to prevent complications in composite resin therapy

International Nuclear Information System (INIS)

Okamoto, Y.; Shintani, H.; Yamaki, M.

1990-01-01

Preparative treatment is the preferred method to protect the dentin and pulp from complications in composite resin therapy. This study investigated the in vivo effects of the polycarboxylate cement containing zinc fluoride and tannic acid in composite resin restorations. Scanning electron micrographs established that the composite resin failed to contact the axial wall. The gaps varied from 10 to 60 microns. However, this polycarboxylate cement was shown to provide excellent adaptation to dentin when used as a base and its chemical adhesion allowed it to make close contact with the unetched dentin. The newly developed electron probe x-ray microanalyzer revealed that the in vivo penetration of fluoride and zinc occurred through the dentinal tubules. When this polycarboxylate cement was used, the orifices of dentinal tubules were partially occluded, possibly with the smear layer fixed by tannic acid. In addition, by releasing the components, this polycarboxylate cement adds acid resistance to dentin and increases the resistance of dentin collagen to proteolytic enzymes. As such this polycarboxylate cement offers advantages as a base to composite resin therapy

Preparation of silver-cuprous oxide/stearic acid composite coating with superhydrophobicity on copper substrate and evaluation of its friction-reducing and anticorrosion abilities

Energy Technology Data Exchange (ETDEWEB)

Li, Peipei [Key Laboratory of Ministry of Education for Special Functional Materials, Henan University, Kaifeng 475004 (China); Chen, Xinhua [College of Chemistry and Chemical Engineering, Xuchang University, Xuchang 461000 (China); Yang, Guangbin; Yu, Laigui [Key Laboratory of Ministry of Education for Special Functional Materials, Henan University, Kaifeng 475004 (China); Zhang, Pingyu, E-mail: pingyu@henu.edu.cn [Key Laboratory of Ministry of Education for Special Functional Materials, Henan University, Kaifeng 475004 (China)

2014-01-15

A simple two-step solution immersion process was combined with surface-modification by stearic acid to prepare superhydrophobic coatings on copper substrates so as to reduce friction coefficient, increase wear resistance and improve the anticorrosion ability of copper. Briefly, cuprous oxide (Cu{sub 2}O) crystal coating with uniform and compact tetrahedron structure was firstly created by immersing copper substrate in 2 mol L{sup −1} NaOH solution. As-obtained Cu{sub 2}O coating was then immersed in 0.33 mmol L{sup −1} AgNO{sub 3} solution to incorporate silver nanoparticles, followed by modification with stearic acid (denoted as SA) coating to achieve hydrophobicity. The surface morphology and chemical composition of silver-cuprous oxide/stearic acid (denoted as Ag-Cu{sub 2}O/SA) composite coating were investigated using a scanning electron microscope and an X-ray photoelectron spectroscope (XPS); and its phase structure was examined with an X-ray diffractometer (XRD). Moreover, the contact angle of water on as-prepared Ag-Cu{sub 2}O/SA composite coating was measured, and its friction-reducing and anticorrosion abilities were evaluated. It was found that as-prepared Ag-Cu{sub 2}O/SA composite coating has a water contact angle of as high as 152.4{sup o} and can provide effective friction-reducing, wear protection and anticorrosion protection for copper substrate, showing great potential for surface-modification of copper.

Preparation and properties of lauric acid/silicon dioxide composites as form-stable phase change materials for thermal energy storage

International Nuclear Information System (INIS)

Fang Guiyin; Li Hui; Liu Xu

2010-01-01

Form-stable lauric acid (LA)/silicon dioxide (SiO 2 ) composite phase change materials were prepared using sol-gel methods. The LA was used as the phase change material for thermal energy storage, with the SiO 2 acting as the supporting material. The structural analysis of these form-stable LA/SiO 2 composite phase change materials was carried out using Fourier transformation infrared spectroscope (FT-IR). The microstructure of the form-stable composite phase change materials was observed by a scanning electronic microscope (SEM). The thermal properties and thermal stability were investigated by a differential scanning calorimeter (DSC) and a thermogravimetric analysis apparatus (TGA), respectively. The SEM results showed that the LA was well dispersed in the porous network of SiO 2 . The DSC results indicated that the melting latent heat of the form-stable composite phase change material is 117.21 kJ kg -1 when the mass percentage of the LA in the SiO 2 is 64.8%. The results of the TGA showed that these materials have good thermal stability. The form-stable composite phase change materials can be used for thermal energy storage in waste heat recovery and solar heating systems.

Compositional and functional features of humic acid-like fractions from vermicomposting of sewage sludge and cow dung

Energy Technology Data Exchange (ETDEWEB)

Li Xiaowei [State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Xing Meiyan, E-mail: xmy5000@163.com [State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Yang Jian; Huang Zhidong [State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China)

2011-01-30

The chemical changes occurring in five different substrates of sewage sludge spiked with different proportions of cow dung after vermicomposting with Eisenia foetida for 90 days were investigated. Their humic acid-like (HAL) fractions were isolated to determine the elemental and functional composition, and structural and functional characteristics using ultraviolet/visible, Fourier transform infrared (FT-IR) and fluorescence spectroscopies and scanning electron microscopy. After vermicomposting, the total organic C and C/N ratio decreased, and the total extractable C and humic acid (HA) C increased in all substrates. In the HAL fractions, the C and H contents, C/N and C/O and aliphatic structures, proteinaceous components and carbohydrates decreased, while the O and N and acidic functional group contents and C/H ratio, aromaticity and polycondensation structures increased. Further, the results suggest that the addition of cow dung to sewage sludge could improve the quality of organic matter humification of the substrates. The structures of HAL fractions in vermicomposts resembled those typical of soil HA, especially the vermicompost of cow dung alone. Scanning electron microscopy showed the microstructure of HAL fraction in final product became close-grained and lumpy. Overall results indicate that vermicomposting was an efficient technology for promoting organic matter (OM) humification in sewage sludge and cow dung alone, as well as in mixtures of both materials, improving their quality and environmental safety as a soil OM resource for utilization as soil amendments.

Compositional and functional features of humic acid-like fractions from vermicomposting of sewage sludge and cow dung.

Science.gov (United States)

Li, Xiaowei; Xing, Meiyan; Yang, Jian; Huang, Zhidong

2011-01-30

The chemical changes occurring in five different substrates of sewage sludge spiked with different proportions of cow dung after vermicomposting with Eisenia foetida for 90 days were investigated. Their humic acid-like (HAL) fractions were isolated to determine the elemental and functional composition, and structural and functional characteristics using ultraviolet/visible, Fourier transform infrared (FT-IR) and fluorescence spectroscopies and scanning electron microscopy. After vermicomposting, the total organic C and C/N ratio decreased, and the total extractable C and humic acid (HA) C increased in all substrates. In the HAL fractions, the C and H contents, C/N and C/O and aliphatic structures, proteinaceous components and carbohydrates decreased, while the O and N and acidic functional group contents and C/H ratio, aromaticity and polycondensation structures increased. Further, the results suggest that the addition of cow dung to sewage sludge could improve the quality of organic matter humification of the substrates. The structures of HAL fractions in vermicomposts resembled those typical of soil HA, especially the vermicompost of cow dung alone. Scanning electron microscopy showed the microstructure of HAL fraction in final product became close-grained and lumpy. Overall results indicate that vermicomposting was an efficient technology for promoting organic matter (OM) humification in sewage sludge and cow dung alone, as well as in mixtures of both materials, improving their quality and environmental safety as a soil OM resource for utilization as soil amendments. Copyright © 2010 Elsevier B.V. All rights reserved.

Compositional and functional features of humic acid-like fractions from vermicomposting of sewage sludge and cow dung

International Nuclear Information System (INIS)

Li Xiaowei; Xing Meiyan; Yang Jian; Huang Zhidong

2011-01-01

The chemical changes occurring in five different substrates of sewage sludge spiked with different proportions of cow dung after vermicomposting with Eisenia foetida for 90 days were investigated. Their humic acid-like (HAL) fractions were isolated to determine the elemental and functional composition, and structural and functional characteristics using ultraviolet/visible, Fourier transform infrared (FT-IR) and fluorescence spectroscopies and scanning electron microscopy. After vermicomposting, the total organic C and C/N ratio decreased, and the total extractable C and humic acid (HA) C increased in all substrates. In the HAL fractions, the C and H contents, C/N and C/O and aliphatic structures, proteinaceous components and carbohydrates decreased, while the O and N and acidic functional group contents and C/H ratio, aromaticity and polycondensation structures increased. Further, the results suggest that the addition of cow dung to sewage sludge could improve the quality of organic matter humification of the substrates. The structures of HAL fractions in vermicomposts resembled those typical of soil HA, especially the vermicompost of cow dung alone. Scanning electron microscopy showed the microstructure of HAL fraction in final product became close-grained and lumpy. Overall results indicate that vermicomposting was an efficient technology for promoting organic matter (OM) humification in sewage sludge and cow dung alone, as well as in mixtures of both materials, improving their quality and environmental safety as a soil OM resource for utilization as soil amendments.

Results of breeding for modified C18-fatty acid composition in sunflower

International Nuclear Information System (INIS)

Schmidt, L.; Marquard, R.; Friedt, W.

1990-01-01

Full text: In an earlier experiment, KUEBLER was able to select sunflower lines with modified fatty acid composition after induced mutagenesis. From this material, genotypes with more than 80% linoleic acid content could be selected, whereas the highest level of oleic acid obtained was 30% under field conditions and up to 50% in the phytotron. Recently, inbred lines with up to 90% oleic acid could be selected from a progeny of the Russian cultivar Pervenets, which has high oleic acid content inherited by one major, partially dominant gene. The inheritance of oleic/linoleic acid content in our own material is not fully understood yet, but is highly heritable. (author)

Carcass properties, chemical content and fatty acid composition of ...

African Journals Online (AJOL)

The aim of this study was to examine carcass properties and variability in chemical content and fatty acid composition in the musculus longissimus lumborum et thoracis (MLLT) of different genotypes of pigs. Of 36 male castrated animals used in the trial, 24 were from two strains of Mangalitsa pigs (12 Swallow - bellied ...

Effect of phosphoric acid on the morphology and tensile properties of halloysite-polyurethane composites

Science.gov (United States)

Gaaz, Tayser Sumer; Luaibi, Hasan Mohammed; Al-Amiery, Ahmed A.; Kadhum, Abdul Amir H.

2018-06-01

The high aspect ratio of nanoscale reinforcements enhances the tensile properties of pure polymer matrix. The composites were first made by adding halloysite nanotubes (HNTs) at low weight percentages of 1, 2, and 3 wt% to thermoplastic polyurethane (TPU). Then, HNTs were phosphoric acid-treated before adding to TPU at same weight percentage to create phosphoric acid HNTs-TPU composites. The samples were fabricated using injection moulding. The HNTs-TPU composites were characterized according to the tensile properties including tensile strength, tensile strain and Young's modulus. The loading has shown its highest tensile values at 2 wt% HNTs loading and same findings are shown with the samples that treated with phosphoric acid. The tensile strength increased to reach 24.65 MPa compare with the 17.7 MPa of the neat TPU showing about 26% improvement. For the phosphoric acid-treated composites, the improvement has reached 35% compared to the neat sample. Regarding the tensile stain, the improvement was about 83% at 2 wt% HNTs loading. For Young's modulus, the results obtained in this study have shown that Young's modulus is linearly improved with either the loading content or the phosphoric acid treated achieving its highest values at 3 wt% HNTs of 14.53 MPa and 16.27 MPa for untreated and treated, respectively. FESEM results showed that HNTs were well dispersed in TPU matrix. Thus, HNTs-TPU has improved tensile properties compared with pure TPU due to the addition of nanofiller.

Temperature-dependent surface structure, composition, and electronic properties of the clean SrTiO3(111) crystal face: Low-energy-electron diffraction, Auger-electron spectroscopy, electron energy loss, and ultraviolet-photoelectron spectroscopy studies

International Nuclear Information System (INIS)

Lo, W.J.; Somorjai, G.A.

1978-01-01

Low-energy-electron diffraction, Auger-electron spectroscopy, electron-energy-loss, and ultraviolet-photoelectron spectroscopies were used to study the structure, composition, and electron energy distribution of a clean single-crystal (111) face of strontium titanate (perovskite). The dependence of the surface chemical composition on the temperature has been observed along with corresponding changes in the surface electronic properties. High-temperature Ar-ion bombardment causes an irreversible change in the surface structure, stoichiometry, and electron energy distribution. In contrast to the TiO 2 surface, there are always significant concentrations of Ti 3+ in an annealed ordered SrTiO 3 (111) surface. This stable active Ti 3+ monolayer on top of a substrate with large surface dipole potential makes SrTiO 3 superior to TiO 2 when used as a photoanode in the photoelectrochemical cell

Gamma radiation effects on fattly acid composition of lipids in cotton leaves

International Nuclear Information System (INIS)

Arslanova, S.V.; Stepanenko, G.A.; Umarov, A.K.; Nazirov, N.N.

1976-01-01

The mechanism of high irradiation dose (30 kR) effect on the lipid fatty acid composition of cotton leaves was studied in the ontogenesis. The experiment was carried out in vegetation vials (capacity 25 kg, humidity level - 65% of full water capacity). Before seeding, each vial was fertilized with 5g P 2 O 5 , 3g K 2 O and 5gN as an auxillary nutrition during vegetation. The test vials also contained 0.4 - 0.5 g CaO per kg of soil. A portion of irradiated seeds was soaked in 1.5% solution of CaO and Ca(NO 3 ) 2 before seeding. The cotton seeds were gamma-irradiated at 50 R/sec in the Institute of Nuclear Physics, Usbec SSR Academy of Sciences. The fatty acid composition of mature leaf lipids determined by gas-liquid chromatography proved to change in the blooming phase. Leaves of irradiated plants contained traces of myristic acid, higher levels of palmitic, palmitoleinic and strearinic acids and lower levels of oleinic and linoleic acids. Lower content of fatty acids with long carbon chains seemed to handicap the renewal of membranes and their components, especially in mitochondria. When irradiated seeds were soaked in calcium salt solution and CaO is added to the soil, the amount of unsaturated long chain fatty acids increased. The fact probably promotes the membrane renewal in irradiated plants

Effect of electron beam irradiation on thermal and mechanical properties of aluminum based epoxy composites

Science.gov (United States)

Visakh, P. M.; Nazarenko, O. B.; Sarath Chandran, C.; Melnikova, T. V.; Nazarenko, S. Yu.; Kim, J.-C.

2017-07-01

The epoxy resins are widely used in nuclear and aerospace industries. The certain properties of epoxy resins as well as the resistance to radiation can be improved by the incorporation of different fillers. This study examines the effect of electron beam irradiation on the thermal and mechanical properties of the epoxy composites filled with aluminum nanoparticles at percentage of 0.35 wt%. The epoxy composites were exposed to the irradiation doses of 30, 100 and 300 kGy using electron beam generated by the linear electron accelerator ELU-4. The effects of the doses on thermal and mechanical properties of the aluminum based epoxy composites were investigated by the methods of thermal gravimetric analysis, tensile test, and dynamic mechanical analysis. The results revealed that the studied epoxy composites showed good radiation resistance. The thermal and mechanical properties of the aluminum based epoxy composites increased with increasing the irradiation dose up to 100 kGy and decreased with further increasing the dose.

Can X-ray spectrum imaging replace backscattered electrons for compositional contrast in the scanning electron microscope?

Science.gov (United States)

Newbury, Dale E; Ritchie, Nicholas W M

2011-01-01

The high throughput of the silicon drift detector energy dispersive X-ray spectrometer (SDD-EDS) enables X-ray spectrum imaging (XSI) in the scanning electron microscope to be performed in frame times of 10-100 s, the typical time needed to record a high-quality backscattered electron (BSE) image. These short-duration XSIs can reveal all elements, except H, He, and Li, present as major constituents, defined as 0.1 mass fraction (10 wt%) or higher, as well as minor constituents in the range 0.01-0.1 mass fraction, depending on the particular composition and possible interferences. Although BSEs have a greater abundance by a factor of 100 compared with characteristic X-rays, the strong compositional contrast in element-specific X-ray maps enables XSI mapping to compete with BSE imaging to reveal compositional features. Differences in the fraction of the interaction volume sampled by the BSE and X-ray signals lead to more delocalization of the X-ray signal at abrupt compositional boundaries, resulting in poorer spatial resolution. Improved resolution in X-ray elemental maps occurs for the case of a small feature composed of intermediate to high atomic number elements embedded in a matrix of lower atomic number elements. XSI imaging strongly complements BSE imaging, and the SDD-EDS technology enables an efficient combined BSE-XSI measurement strategy that maximizes the compositional information. If 10 s or more are available for the measurement of an area of interest, the analyst should always record the combined BSE-XSI information to gain the advantages of both measures of compositional contrast. Copyright © 2011 Wiley Periodicals, Inc.

Modified Polyacrylic Acid-Zinc Composites: Synthesis, Characterization and Biological Activity

Directory of Open Access Journals (Sweden)

Mohammed Rafi Shaik

2016-02-01

Full Text Available Polyacrylic acid (PAA is an important industrial chemical, which has been extensively applied in various fields, including for several biomedical purposes. In this study, we report the synthesis and modification of this polymer with various phenol imides, such as succinimide, phthalimide and 1,8-naphthalimide. The as-synthesized derivatives were used to prepare polymer metal composites by the reaction with Zn+2. These composites were characterized by using various techniques, including NMR, FT-IR, TGA, SEM and DSC. The as-prepared PAA-based composites were further evaluated for their anti-microbial properties against various pathogens, which include both Gram-positive and Gram-negative bacteria and different fungal strains. The synthesized composites have displayed considerable biocidal properties, ranging from mild to moderate activities against different strains tested.

UPS and DFT investigation of the electronic structure of gas-phase trimesic acid

Energy Technology Data Exchange (ETDEWEB)

Reisberg, L., E-mail: rebban@ut.ee [Institute of Physics, University of Tartu, W. Oswaldi 1, EE-50411 Tartu (Estonia); Pärna, R. [Institute of Physics, University of Tartu, W. Oswaldi 1, EE-50411 Tartu (Estonia); MAX IV Laboratory, Lund University, Fotongatan 2, 225 94 Lund (Sweden); Kikas, A.; Kuusik, I.; Kisand, V. [Institute of Physics, University of Tartu, W. Oswaldi 1, EE-50411 Tartu (Estonia); Hirsimäki, M.; Valden, M. [Surface Science Laboratory, Optoelectronics Research Centre, Tampere University of Technology, FIN-33101 Tampere (Finland); Nõmmiste, E. [Institute of Physics, University of Tartu, W. Oswaldi 1, EE-50411 Tartu (Estonia)

2016-11-15

Highlights: • In the current study outer valence band electronic structure of benzene-1,3,5-tricarboxylic acid was interpreted. • Experimental and calculated trimesic acid (TMA) spectrum were compared to ones of benzene and benzoic acid. • It is shown that similarities between MO energies and shapes for benzene and TMA exists. • Addition of carboxyl groups to the benzene ring clearly correlates with increasing binding energy of HOMO. - Abstract: Benzene-1,3,5-tricarboxylic acid (trimesic acid, TMA) molecules in gas-phase have been investigated by using valence band photoemission. The photoelectron spectrum in the binding energy region from 9 to 22 eV is interpreted by using density functional theory calculations. The electronic structure of TMA is compared with benzene and benzoic acid in order to demonstrate changes in molecular orbital energies induced by addition of carboxyl groups to benzene ring.

Study on fatty acids composition of lipid class in fish oil, proximate analysis and calorie value of kijar in Iran

Directory of Open Access Journals (Sweden)

Ali Aberoumand

2017-01-01

Full Text Available 14.00 This aim of this research was to determine fatty acids and raw proximate composition and calorie value of fish Kijar in Iran. The fatty acids and proximate composition Kijar was determined. The established AOAC (Association of Official Agricultural Chemist, USA methods were followed for composition bio chemical of fish. Mean moisture, fat, protein, ash, carbohydrate contents and calorie value of raw fish were 70.81%, 5.88%, 17.80%, 3.41%, 2.1% and 132.52 kcal, respectively. Among fatty acids, palmitic acid was a major fatty acid while stearic acid was the other major constituent. Unsaturated monoenoic fatty acids (oleic and palmitoleic acids were major constituents. Important unsaturated fatty acids such as EPA and DHA, were also identified. percentage composition of fatty acids in the lipid classes of oil of Saurida undosquamis which the saturated fatty acids ranges from 58% to 72.14%. Palmitic acid is predominant and its composition ranges 38.64% to 48.98% while stearic acid ranges from 11.35% to 19.50%. Among unsaturated fatty acids, monoenoic are the major fatty acids. Oleic acid ranges from 12.15% to 27.48%. It is concluded that fish kijar found as health seafood for Iranian southern peoples form point of view of nutritional values and valuable fatty acids. Therefore it is recommended people put this fish in diet basket and it consumed three times in the week. Normal 0 false false false EN-US X-NONE AR-SA

Preparation of TiO2-based nanotubes/nanoparticles composite thin film electrodes for their electron transport properties

International Nuclear Information System (INIS)

Zhao, Wanyu; Fu, Wuyou; Chen, Jingkuo; Li, Huayang; Bala, Hari; Wang, Xiaodong; Sun, Guang; Cao, Jianliang; Zhang, Zhanying

2015-01-01

The composite thin film electrodes were prepared with one-dimensional (1D) TiO 2 -B nanotubes (NTs) and zero-dimensional TiO 2 nanoparticles (NPs) based on different weight ratios. The electron transport properties of the NTs/NPs composite thin film electrodes applied for dye-sensitized solar cells had been investigated systematically. The results indicated that although the amount of dye adsorption decreased slightly, the devices with the NTs/NPs composite thin film electrodes could obtain higher open-circuit voltage and overall conversion efficiency compared to devices with pure TiO 2 NPs electrodes by rational tuning the weight ratio of TiO 2 -B NTs and TiO 2 NPs. When the weight ratio of TiO 2 -B NTs in the NTs/NPs composite thin film electrodes increased, the density of states and recombination rate decreased. The 1D structure of TiO 2 -B NTs can provide direct paths for electron transport, resulting in higher electron lifetime, electron diffusion coefficient and electron diffusion length. The composite thin film electrodes possess the merits of the rapid electron transport of TiO 2 -B NTs and the high surface area of TiO 2 NPs, which has great applied potential in the field of photovoltaic devices. - Highlights: • The composite thin film electrodes (CTFEs) were prepared with nanotubes and nanoparticles. • The CTFEs possess the rapid electron transport and high surface area. • The CTFEs exhibit lower recombination rate and longer electron life time. • The CTFEs have great applied potential in the field of photovoltaic devices

Fatty acids composition of microalgae Chlorella vulgaris can be ...

African Journals Online (AJOL)

Varying culture methods of Chlorella vulgaris (CV) has been associated with different nutrient composition. The aim of this study was to investigate the fatty acid contents and other nutrients of CV subjected to various culturing conditions. We found that CV cultured under 24 h light and 10% CO2 showed the best growth rates ...

Electrochemical and conversion electron Moessbauer study of corrosion induced by acid rain

International Nuclear Information System (INIS)

Vertes, C.; Lakatos-Varsanyi, M.; Vertes, A.; Meisel, W.; Guetlich, P.

1993-01-01

The passivation of low carbon steel was studied in aqueous solution of 0.5M Na 2 SO 4 +0.001M NaHSO 3 (pH 3.5, 6.5 and 8.5) which can be considered as a model of acid rain. The used conversion electron Moessbauer spectroscopy (CEMS) with the complementary electrochemical investigations proved that the sulfite ions induce pitting corrosion at pH 3.5 and 6.5, while the measurements showed much weaker pitting at pH 8.5. The compositions and thicknesses of the passive films formed during the electrochemical treatments are determined from the CEM spectra. Only γ-FeOOH was found on the surface of the samples at pH 6.5 and 8.5. Nevertheless, at pH 3.5 the sextet belonging to Fe 3 C appears in the spectra, and also FeSO 4 .H 2 O could be detected in low concentration. (orig.)

Direct electron transfer of hemoglobin in a CdS nanorods and Nafion composite film on carbon ionic liquid electrode

International Nuclear Information System (INIS)

Sun Wei; Wang Dandan; Li Guicun; Zhai Ziqin; Zhao Ruijun; Jiao Kui

2008-01-01

In this paper the direct electron transfer of hemoglobin (Hb) was carefully investigated by using a room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF 6 ) modified carbon paste electrode (CILE) as the basal working electrode. Hb was immobilized on the surface of CILE with the nanocomposite film composed of Nafion and CdS nanorods by a step-by-step method. UV-vis and FT-IR spectra showed that Hb in the composite film remained its native structure. The direct electrochemical behaviors of Hb in the composite film were further studied in a pH 7.0 phosphate buffer solution (PBS). A pair of well-defined and quasi-reversible cyclic voltammetric peaks of Hb was obtained with the formal potential (E 0 ') at -0.295 V (vs. SCE), which was the characteristic of heme Fe(III)/Fe(II) redox couples. The direct electrochemistry of Hb was achieved on the modified electrode and the apparent heterogeneous electron transfer rate constant (k s ) was calculated to be 0.291 s -1 . The formal potentials of Hb Fe(III)/Fe(II) couple shifted negatively with the increase of buffer pH and a slope value of -45.1 mV/pH was got, which indicated that one electron transfer accompanied with one proton transportation. The fabricated Hb sensor showed good electrocatalytic manner to the reduction of trichloroacetic acid (TCA)

Fatty acid composition of adipose tissue triglycerides after weight loss and weight maintenance

DEFF Research Database (Denmark)

Kunešová, M; Hlavatý, P; Tvrzická, E

2012-01-01

Fatty acid composition of adipose tissue changes with weight loss. Palmitoleic acid as a possible marker of endogenous lipogenesis or its functions as a lipokine are under debate. Objective was to assess the predictive role of adipose triglycerides fatty acids in weight maintenance in participants...... of the DIOGENES dietary intervention study. After an 8-week low calorie diet (LCD) subjects with > 8 % weight loss were randomized to 5 ad libitum weight maintenance diets for 6 months: low protein (P)/low glycemic index (GI) (LP/LGI), low P/high GI (LP/HGI), high P/low GI (HP/LGI), high P/high GI (HP....../HGI), and a control diet. Fatty acid composition in adipose tissue triglycerides was determined by gas chromatography in 195 subjects before the LCD (baseline), after LCD and weight maintenance. Weight change after the maintenance phase was positively correlated with baseline adipose palmitoleic (16:1n-7...

Tuning the conformation of synthetic co-polypeptides of serine and glutamic acid through control over polymer composition

NARCIS (Netherlands)

Canning, A.; Pasquazi, A.; Fijten, M.; Rajput, S.; Buttery, L.; Aylott, J.W.; Zelzer, M.

2016-01-01

Ring opening polymerization (ROP) of N-carboxy anhydride (NCA) amino acids presents a rapid way to synthesize high molecular weight polypeptides with different amino acid compositions. The compositional and functional versatility of polypeptides make these materials an attractive choice for

The effect of composition, electron irradiation and quenching on ...

Indian Academy of Sciences (India)

The ionic conductivity at room temperature exhibits a characteristic double peak for the composition = 20 and 70. Both electron beam irradiation and quenching at low temperature have resulted in an increase in conductivity by 1–2 orders of magnitude. The enhancement of conductivity upon irradiation and quenching is ...

PHOSPHOLIPIDS FROM PUMPKIN (Cucurbita moschata (Duch. Poir SEED KERNEL OIL AND THEIR FATTY ACID COMPOSITION

Directory of Open Access Journals (Sweden)

Tri Joko Raharjo

2011-07-01

Full Text Available The phospholipids (PL of pumpkin (Cucurbita moschata (Duch Poir seed kernel and their fatty acid composition were investigated. The crude oil was obtained by maceration with isopropanol followed by steps of extraction yielded polar lipids. The quantitative determination of PLs content of the dried pumpkin seed kernel and their polar lipids were calculated based on the elemental phosphorus (P contents which was determined by means of spectrophotometric methods. PL classes were separated from polar lipids via column chromatography. The fatty acid composition of individual PL was identified by gas chromatography-mass spectrometry (GC-MS. The total of PL in the pumpkin seed kernels was 1.27% which consisted of phosphatidylcholine (PC, phosphatidylserine (PS and phosphatidyletanolamine (PE. The predominant fatty acids of PL were oleic and palmitic acid in PC and PE while PS's fatty acid were dominantly consisted of oleic acid and linoleic acid.

Investigation of the fatty acid composition of the snail Succinea putris L.

NARCIS (Netherlands)

Horst, D.J. van der; Voogt, P.A.

1969-01-01

1. 1. The incorporation of 1-14C-acetate into some classes of lipids by Succinea putris L. is investigated. 2. 2. This snail is able to synthesize fatty acids from injected acetate. 3. 3. The acetate is also used for the synthesis of non-saponifiable lipids. 4. 4. The fatty acid composition of

Morphology and thermal degradation study of poly(lactic acid)/synthetic mica composites

International Nuclear Information System (INIS)

Souza, D.H.S.; Dias, M.L.

2010-01-01

Poly(lactic acid) (PLA)/synthetic mica composites has been little studied in the literature. In this work, an organophilic synthetic mica was used to prepare PLA nanocomposites. The composites were obtained at an internal mixer containing 3, 5, 7 and 10 wt% of mica. The materials were analyzed by x-ray diffraction, thermogravimetric analysis and gel permeation chromatography. (author)

Elicitor and nitrogen applications to Garnacha, Graciano and Tempranillo vines: effect on grape amino acid composition.

Science.gov (United States)

Gutiérrez-Gamboa, Gastón; Portu, Javier; López, Rosa; Santamaría, Pilar; Garde-Cerdán, Teresa

2018-04-01

Elicitors and nitrogen foliar applications to vineyards could regulate grape nitrogen composition, which has an important effect on grape and wine quality. Thus the aim of this research was to study the effect of foliar elicitor treatments, methyl jasmonate (MeJ) and yeast extract (YE), and foliar nitrogen applications, urea (Ur) and phenylalanine (Phe), to Garnacha, Graciano and Tempranillo vines on grape amino acid composition. The results showed that elicitor and nitrogen foliar applications to Garnacha and Tempranillo grapevines decreased the must amino acid concentration. However, Phe application to these two grapevines increased the must Phe content. The treatments applied to Graciano grapevines barely effected the grape amino acid content. According to the percentage of variance attributable, the variety had a higher impact on the must amino acid composition than the treatments and their interaction, except in certain amino acids such as Phe. The influence of elicitor and nitrogen foliar applications to grapevines on grape amino acid concentration was strongly conditioned by the variety. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Electron transfer reactions of ruthenium(II) complexes with polyphenolic acids in micelles

Energy Technology Data Exchange (ETDEWEB)

Rajeswari, Angusamy [School of Chemistry, Madurai Kamaraj University, Madurai 625 021 (India); Department of Chemistry, Fatima College, Madurai 625 018 (India); Ramdass, Arumugam [School of Chemistry, Madurai Kamaraj University, Madurai 625 021 (India); Research Department of Chemistry, Aditanar College of Arts and Science, Tiruchendur 628 216 (India); Muthu Mareeswaran, Paulpandian [School of Chemistry, Madurai Kamaraj University, Madurai 625 021 (India); Department of Industrial Chemistry, Alagappa University, Karaikudi 630 003 (India); Rajagopal, Seenivasan, E-mail: rajagopalseenivasan@yahoo.com [School of Chemistry, Madurai Kamaraj University, Madurai 625 021 (India)

2016-02-15

The electron transfer in a microhetrogeneous system is a perfect mimic of biological electron transfer. The electron transfer between biologically important phenolic acids and ruthenium (II) complexes is systematically studied in the presence of anionic and cationic micelles. The photophysical properties of these ruthenium (II) complexes with anionic and cationic micelles and their binding abilities with these two type of micelles are also studies using absorption, emission and excited state lifetime spectral techniques. Pseudophase Ion Exchange (PIE) Model is applied to derive mechanism of electron transfer in two types of micelles. - Highlights: • Effect of microhetrogeneous system is studied using ruthenium (II) complexes and gallic acid is studied. • Pseudophase Ion exchange model is applied to derive the mechanism. • Binding constants are in the range of 10{sup 2}–10{sup 4} M{sup −1}.

Chemical composition and electronic structure of the passive layer formed on stainless steels in a glucose-oxidase solution

Energy Technology Data Exchange (ETDEWEB)

Marconnet, C. [Laboratoire de Genie des Procedes et des Materiaux, Ecole Centrale Paris, Grande Voie des Vignes, 92290 CHATENAY-MALABRY (France)], E-mail: cyril.marconnet@yahoo.fr; Wouters, Y. [Science et Ingenierie des Materiaux et Procedes, Institut National Polytechnique de Grenoble, F-38402 Saint-Martin d' Heres Cedex (France); Miserque, F. [Laboratoire de Reactivite des Surfaces et des Interfaces, CEA Saclay, Bat. 391, 91191 GIF-SUR-YVETTE (France); Dagbert, C. [Laboratoire de Genie des Procedes et des Materiaux, Ecole Centrale Paris, Grande Voie des Vignes, 92290 CHATENAY-MALABRY (France)], E-mail: catherine.dagbert@ecp.fr; Petit, J.-P. [Laboratoire d' Electrochimie et de Physico-chimie des Materiaux et des Interfaces, INPG, F-38402 Saint-Martin d' Heres Cedex (France); Galerie, A. [Science et Ingenierie des Materiaux et Procedes, Institut National Polytechnique de Grenoble, F-38402 Saint-Martin d' Heres Cedex (France); Feron, D. [Service de Corrosion et du Comportement des Materiaux dans leur Environnement, CEA Saclay, Bat. 458, 91191 GIF-SUR-YVETTE (France)

2008-12-01

This article deals with the interaction between the passive layer formed on UNS S30403 and S31254 stainless steels and an enzymatic solution containing glucose oxidase (GOx) and its substrate D-glucose. This enzymatic solution is often used to reproduce in laboratory the ennoblement occuring in non-sterile aerated aqueous environments because of the biofilm settlement on the surface of the metallic material. GOx catalyses the oxidation of D-glucose to gluconic acid by reducing oxygen to hydrogen peroxide and produces an organic acid. Thanks to photocurrent measurements, XPS analysis and Mott-Schottky diagrams, it is here shown that such an environment generates modifications in the chemical composition and electronic structure of the passive layer: it induces a relative enrichment of the n-type semi-conducting phase containing chromium (chromine Cr{sub 2}O{sub 3}) and an increase of the donors density in the space charge region.

Chemical composition and electronic structure of the passive layer formed on stainless steels in a glucose-oxidase solution

International Nuclear Information System (INIS)

Marconnet, C.; Wouters, Y.; Miserque, F.; Dagbert, C.; Petit, J.-P.; Galerie, A.; Feron, D.

2008-01-01

This article deals with the interaction between the passive layer formed on UNS S30403 and S31254 stainless steels and an enzymatic solution containing glucose oxidase (GOx) and its substrate D-glucose. This enzymatic solution is often used to reproduce in laboratory the ennoblement occuring in non-sterile aerated aqueous environments because of the biofilm settlement on the surface of the metallic material. GOx catalyses the oxidation of D-glucose to gluconic acid by reducing oxygen to hydrogen peroxide and produces an organic acid. Thanks to photocurrent measurements, XPS analysis and Mott-Schottky diagrams, it is here shown that such an environment generates modifications in the chemical composition and electronic structure of the passive layer: it induces a relative enrichment of the n-type semi-conducting phase containing chromium (chromine Cr 2 O 3 ) and an increase of the donors density in the space charge region

Effect of vegetable oils on fatty acid composition and cholesterol content of chicken frankfurters

Science.gov (United States)

Belichovska, D.; Pejkovski, Z.; Belichovska, K.; Uzunoska, Z.; Silovska-Nikolova, A.

2017-09-01

To study the effect of pork adipose tissue substitution with vegetable oils in chicken frankfurters, six frankfurter formulations were produced: control; with pork backfat; with olive oil; with rapeseed oil; with sunflower oil; with palm oil, and; with a mixture of 12% rapeseed oil and 8% palm oil. Fatty acid composition and cholesterol content and some oxides thereof were determined in the final products. The use of vegetable oils resulted in improvement of the fatty acid composition and nutritional of frankfurters. Frankfurters with vegetable oils contained significantly less cholesterol and some of its oxides, compared to the frankfurters with pork fat. The formulation with palm oil had the least favourable fatty acid composition. The use of 12% rapeseed oil improved the ratio of fatty acids in frankfurters with a mixture of rapeseed and palm oils. Complete pork fat replacement with vegetable oils in chicken frankfurter production is technologically possible. The mixture of 12% rapeseed oil and 8% palm oil is a good alternative to pork fat from health aspects. Further research is needed to find the most appropriate mixture of vegetable oils, which will produce frankfurters with good sensory characteristics, a more desirable fatty acid ratio and high nutritional value.

Long-Term Effect of Docosahexaenoic Acid Feeding on Lipid Composition and Brain Fatty Acid-Binding Protein Expression in Rats

Directory of Open Access Journals (Sweden)

Marwa E. Elsherbiny

2015-10-01

Full Text Available Arachidonic (AA and docosahexaenoic acid (DHA brain accretion is essential for brain development. The impact of DHA-rich maternal diets on offspring brain fatty acid composition has previously been studied up to the weanling stage; however, there has been no follow-up at later stages. Here, we examine the impact of DHA-rich maternal and weaning diets on brain fatty acid composition at weaning and three weeks post-weaning. We report that DHA supplementation during lactation maintains high DHA levels in the brains of pups even when they are fed a DHA-deficient diet for three weeks after weaning. We show that boosting dietary DHA levels for three weeks after weaning compensates for a maternal DHA-deficient diet during lactation. Finally, our data indicate that brain fatty acid binding protein (FABP7, a marker of neural stem cells, is down-regulated in the brains of six-week pups with a high DHA:AA ratio. We propose that elevated levels of DHA in developing brain accelerate brain maturation relative to DHA-deficient brains.

Corrosion of graphite composites in phosphoric acid fuel cells

Science.gov (United States)

Christner, L. G.; Dhar, H. P.; Farooque, M.; Kush, A. K.

1986-01-01

Polymers, polymer-graphite composites and different carbon materials are being considered for many of the fuel cell stack components. Exposure to concentrated phosphoric acid in the fuel cell environment and to high anodic potential results in corrosion. Relative corrosion rates of these materials, failure modes, plausible mechanisms of corrosion and methods for improvement of these materials are investigated.

Seed oil content and fatty acid composition of annual halophyte ...

African Journals Online (AJOL)

Suaeda acuminata produces two morphologically distinct types of seeds on the same plant. This study was conducted to compare oil content and fatty acid composition of the two seed morphs. Though oil characteristics between dimorphic seeds showed statistically significant difference, these differences were relatively ...

Photo-oxidation of gaseous ethanol on photocatalyst prepared by acid leaching of titanium oxide/hydroxyapatite composite

International Nuclear Information System (INIS)

Ono, Y.; Rachi, T.; Yokouchi, M.; Kamimoto, Y.; Nakajima, A.; Okada, K.

2013-01-01

Highlights: ► Photocatalyst powder was prepared by acid leaching of TiO 2 /apatite composite. ► The photocatalytic activity was evaluated from in situ FT-IR study using ethanol. ► Apatite in the composite had positive effect for the photo-oxidation of ethanol. ► The enhanced oxidation rate was explained by the difference in deactivation rate. - Abstract: Highly active photocatalysts were synthesized by leaching of heat-treated titanium dioxide (TiO 2 )/hydroxyapatite (HAp) powder with hydrochloric acid at 0.25, 0.50, 0.75 mol/l, and their photocatalytic activities were evaluated from in situ Fourier transform infrared (FT-IR) study of photo-oxidation of gaseous ethanol. By changing the acid concentration, the TiO 2 /HAp composite had different atomic ratios of Ca/Ti (0.0–2.8) and P/Ti (0.3–2.1). It was found that phosphate group remained on the surface of TiO 2 particle even in the sample treated with concentrated acid (0.75 mol/l). These acid-treated samples showed higher rates for ethanol photo-oxidation than the commercial TiO 2 powder, Degussa P25. The highest rate was obtained in the TiO 2 /HAp composite treated with the dilute (0.25 mol/l) acid in spite of its low content of TiO 2 photocatalyst. This enhanced photocatalytic activity was attributed to the result that the deactivation with repeated injections of ethanol gas was suppressed in the TiO 2 /HAp composites compared with the TiO 2 powders

Differences in the fatty-acid composition of rodent spermatozoa are associated to levels of sperm competition

Directory of Open Access Journals (Sweden)

Javier delBarco-Trillo

2015-03-01

Full Text Available Sperm competition is a prevalent phenomenon that drives the evolution of sperm function. High levels of sperm competition lead to increased metabolism to fuel higher sperm velocities. This enhanced metabolism can result in oxidative damage (including lipid peroxidation and damage to the membrane. We hypothesized that in those species experiencing high levels of sperm competition there are changes in the fatty-acid composition of the sperm membrane that makes the membrane more resistant to oxidative damage. Given that polyunsaturated fatty acids (PUFAs are the most prone to lipid peroxidation, we predicted that higher sperm competition leads to a reduction in the proportion of sperm PUFAs. In contrast, we predicted that levels of sperm competition should not affect the proportion of PUFAs in somatic cells. To test these predictions, we quantified the fatty-acid composition of sperm, testis and liver cells in four mouse species (genus Mus that differ in their levels of sperm competition. Fatty-acid composition in testis and liver cells was not associated to sperm competition levels. However, in sperm cells, as predicted, an increase in sperm competition levels was associated with an increase in the proportion of saturated fatty-acids (the most resistant to lipid peroxidation and by a concomitant decrease in the proportion of PUFAs. Two particular fatty acids were most responsible for this pattern (arachidonic acid and palmitic acid. Our findings thus indicate that sperm competition has a pervasive influence in the composition of sperm cells that ultimately may have important effects in sperm function.

Differences in the fatty-acid composition of rodent spermatozoa are associated to levels of sperm competition

Science.gov (United States)

delBarco-Trillo, Javier; Mateo, Rafael; Roldan, Eduardo R. S.

2015-01-01

Sperm competition is a prevalent phenomenon that drives the evolution of sperm function. High levels of sperm competition lead to increased metabolism to fuel higher sperm velocities. This enhanced metabolism can result in oxidative damage (including lipid peroxidation) and damage to the membrane. We hypothesized that in those species experiencing high levels of sperm competition there are changes in the fatty-acid composition of the sperm membrane that makes the membrane more resistant to oxidative damage. Given that polyunsaturated fatty acids (PUFAs) are the most prone to lipid peroxidation, we predicted that higher sperm competition leads to a reduction in the proportion of sperm PUFAs. In contrast, we predicted that levels of sperm competition should not affect the proportion of PUFAs in somatic cells. To test these predictions, we quantified the fatty-acid composition of sperm, testis and liver cells in four mouse species (genus Mus) that differ in their levels of sperm competition. Fatty-acid composition in testis and liver cells was not associated to sperm competition levels. However, in sperm cells, as predicted, an increase in sperm competition levels was associated with an increase in the proportion of saturated fatty-acids (the most resistant to lipid peroxidation) and by a concomitant decrease in the proportion of PUFAs. Two particular fatty acids were most responsible for this pattern (arachidonic acid and palmitic acid). Our findings thus indicate that sperm competition has a pervasive influence in the composition of sperm cells that ultimately may have important effects in sperm function. PMID:25795911

Meteoritic Amino Acids: Diversity in Compositions Reflects Parent Body Histories

Science.gov (United States)

Elsila, Jamie E.; Aponte, Jose C.; Blackmond, Donna G.; Burton, Aaron S.; Dworkin, Jason P.; Glavin, Daniel P.

2016-01-01

The analysis of amino acids in meteorites dates back over 50 years; however, it is only in recent years that research has expanded beyond investigations of a narrow set of meteorite groups (exemplied by the Murchison meteorite) into meteorites of other types and classes. These new studies have shown a wide diversity in the abundance and distribution of amino acids across carbonaceous chondrite groups, highlighting the role of parent body processes and composition in the creation, preservation, or alteration of amino acids. Although most chiral amino acids are racemic in meteorites, the enantiomeric distribution of some amino acids, particularly of the nonprotein amino acid isovaline, has also been shown to vary both within certain meteorites and across carbonaceous meteorite groups. Large -enantiomeric excesses of some extraterrestrial protein amino acids (up to 60) have also been observed in rare cases and point to nonbiological enantiomeric enrichment processes prior to the emergence of life. In this Outlook, we review these recent meteoritic analyses, focusing on variations in abundance, structural distributions, and enantiomeric distributions of amino acids and discussing possible explanations for these observations and the potential for future work.

Carbon isotope composition of individual amino acids in the Murchison meteorite

International Nuclear Information System (INIS)

Engel, M.H.; Macko, S.A.; Silter, J.A.

1996-01-01

A SIGNIFICANT parties of prebiotic organic matter on the early Earth may have been introduced by carbonaceous asteroids and comets. 1 The distribution and stable-isotope composition of individual organic compounds in carbonaceous meteorites, which are thought to be derived from asteroidal parent bodies, may therefore provide important information concerning mechanistic pathways for prebiotic synthesis 2 and the composition of organic matter on Earth before living systems developed. 3 Previous studies 11,12 have shown that meteorite amino acids are enriched in 13 C relatives to their terrestrial counterparts, but individual species were not distinguished. Here we report the 13 C contents of individual amino acids in the Murchison meteorite. The amino acids are enriched in 13 C, indicating an extraterrestrial origin. Alanine is not racemic, and the 13 C enrichment of its D- and L-enantiomers implies that the excess of the L-enantiomer is indigenous rather than terrestrial contamination, suggesting that optically active materials were present in the early Solar System before life began. copyright 1996 American Institute of Physics

Acetic Acid Detection Threshold in Synthetic Wine Samples of a Portable Electronic Nose

Directory of Open Access Journals (Sweden)

Miguel Macías Macías

2012-12-01

Full Text Available Wine quality is related to its intrinsic visual, taste, or aroma characteristics and is reflected in the price paid for that wine. One of the most important wine faults is the excessive concentration of acetic acid which can cause a wine to take on vinegar aromas and reduce its varietal character. Thereby it is very important for the wine industry to have methods, like electronic noses, for real-time monitoring the excessive concentration of acetic acid in wines. However, aroma characterization of alcoholic beverages with sensor array electronic noses is a difficult challenge due to the masking effect of ethanol. In this work, in order to detect the presence of acetic acid in synthetic wine samples (aqueous ethanol solution at 10% v/v we use a detection unit which consists of a commercial electronic nose and a HSS32 auto sampler, in combination with a neural network classifier (MLP. To find the characteristic vector representative of the sample that we want to classify, first we select the sensors, and the section of the sensors response curves, where the probability of detecting the presence of acetic acid will be higher, and then we apply Principal Component Analysis (PCA such that each sensor response curve is represented by the coefficients of its first principal components. Results show that the PEN3 electronic nose is able to detect and discriminate wine samples doped with acetic acid in concentrations equal or greater than 2 g/L.

Chopped basalt fibres: A new perspective in reinforcing poly(lactic acid to produce injection moulded engineering composites from renewable and natural resources

Directory of Open Access Journals (Sweden)

P. Tamas

2013-02-01

Full Text Available This paper focuses on the reinforcing of Poly(lactic acid with chopped basalt fibres by using silane treated and untreated basalt fibres. Composite materials with 5–10–15–20–30–40 wt% basalt fibre contents were prepared from silane sized basalt fibres using extrusion, and injection moulding, while composites with 5–10–15 wt% basalt fibre contents were also prepared by using untreated basalt fibres as control. The properties of the injection moulded composites were extensively examined by using quasi-static (tensile, three-point bending and dynamic mechanical tests (notched and unnotched Charpy impact tests, dynamic mechanical analysis (DMA, differential scanning calorimetry (DSC, heat deflection temperature (HDT analysis, dimensional stability test, as well as melt flow index (MFI analysis and scanning electron microscopic (SEM observations. It was found that silane treated chopped basalt fibres are much more effective in reinforcing Poly(lactic acid than natural fibres; although basalt fibres are not biodegradable but they are still considered as natural (can be found in nature in the form of volcanic rocks and biologically inert. It is demonstrated in this paper that by using basalt fibre reinforcement, a renewable and natural resource based composite can be produced by injection moulding with excellent mechanical properties suitable even for engineering applications. Finally it was shown that by using adequate drying of the materials, composites with higher mechanical properties can be achieved compared to literature data.

Preparation and thermal characterization of oxalic acid dihydrate/bentonite composite as shape-stabilized phase change materials for thermal energy storage

Science.gov (United States)

Han, Lipeng; Xie, Shaolei; Sun, Jinhe; Jia, Yongzhong

2017-03-01

Oxalic acid dihydrate (OAD) which has very high initial phase transition enthalpy is a promising phase change material (PCM). In this paper, shape-stabilized composite PCMs composed of OAD and bentonite were prepared by a facile blending method to overcome the problem of leakage. FT-IR results indicated the interactions between OAD and bentonite, such as the capillary force and the hydrogen bonding, resulting in the confined crystallization process. As a result, the OAD was confined to be amorphous. The thermogravimetric analysis and scanning electron microscope results showed that sample had the best coating effect when the amount of bentonite was 17.7%. The differential scanning calorimetry analyses demonstrated that a decrease in the OAD content was accompanied by a continuous decrease in the melting point and phase change enthalpy of the composites.

Recent developments in altering the fatty acid composition of ruminant-derived foods.

Science.gov (United States)

Shingfield, K J; Bonnet, M; Scollan, N D

2013-03-01

There is increasing evidence to indicate that nutrition is an important factor involved in the onset and development of several chronic human diseases including cancer, cardiovascular disease (CVD), type II diabetes and obesity. Clinical studies implicate excessive consumption of medium-chain saturated fatty acids (SFA) and trans-fatty acids (TFA) as risk factors for CVD, and in the aetiology of other chronic conditions. Ruminant-derived foods are significant sources of medium-chain SFA and TFA in the human diet, but also provide high-quality protein, essential micronutrients and several bioactive lipids. Altering the fatty acid composition of ruminant-derived foods offers the opportunity to align the consumption of fatty acids in human populations with public health policies without the need for substantial changes in eating habits. Replacing conserved forages with fresh grass or dietary plant oil and oilseed supplements can be used to lower medium-chain and total SFA content and increase cis-9 18:1, total conjugated linoleic acid (CLA), n-3 and n-6 polyunsaturated fatty acids (PUFA) to a variable extent in ruminant milk. However, inclusion of fish oil or marine algae in the ruminant diet results in marginal enrichment of 20- or 22-carbon PUFA in milk. Studies in growing ruminants have confirmed that the same nutritional strategies improve the balance of n-6/n-3 PUFA, and increase CLA and long-chain n-3 PUFA in ruminant meat, but the potential to lower medium-chain and total SFA is limited. Attempts to alter meat and milk fatty acid composition through changes in the diet fed to ruminants are often accompanied by several-fold increases in TFA concentrations. In extreme cases, the distribution of trans 18:1 and 18:2 isomers in ruminant foods may resemble that of partially hydrogenated plant oils. Changes in milk fat or muscle lipid composition in response to diet are now known to be accompanied by tissue-specific alterations in the expression of one or more

Preparation of graphene oxide/polypyrrole/multi-walled carbon nanotube composite and its application in supercapacitors

International Nuclear Information System (INIS)

Wang, Bin; Qiu, Jianhui; Feng, Huixia; Sakai, Eiichi

2015-01-01

Highlights: • A novel method for synthesizing graphene oxide/polypyrrole/multi-walled nanotube composites. • Investigation of the effects of the mass ratio of GO, CM and Py on the capacitance of prepared composites. • Excellent electrochemical performance of PCMG composites. - Abstract: We report a novel method for preparing graphene oxide/polypyrrole/multi-walled carbon nanotubes (MWCNTs) composites (PCMG). The MWCNTs are treated by sulfuric acid, nitric acid and thionyl chloride, and then composite with graphene oxide and PPy by in suit polymerization. Transition electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) results show that in 3-D structure of PCMG composites, PPy chains act as the “bridge” between graphene oxide and chlorinated-MWCNTs. Electrochemical tests reveal that the PCMG1-1 composite has high capacitance of 406.7 F g −1 at current density of 0.5 A g −1 , and the capacitance retention of PCMG1-1 composite is 92% after 1000 cycles

Proton conductivity of phosphoric acid doped polybenzimidazole and its composites with inorganic protontic conductors

DEFF Research Database (Denmark)

Li, Qingfeng

2003-01-01

contain inorganic protonic conductors including zirconium phosphate (ZrP), (Zr(HPO4)2. nH2O); phosphotungstic acid (PWA), (H3PW12O40. nH2O); and silicotungstic acid (SiWA), (H4SiW12O40 . nH2O). The conductivity of phosphoric acid doped PBI and PBI composite membranes was found to be dependent on the acid...

Pomegranate seed oil: Effect on 3-nitropropionic acid-induced neurotoxicity in PC12 cells and elucidation of unsaturated fatty acids composition.

Science.gov (United States)

Al-Sabahi, Bushra N; Fatope, Majekodunmi O; Essa, Musthafa Mohamed; Subash, Selvaraju; Al-Busafi, Saleh N; Al-Kusaibi, Fatma S M; Manivasagam, Thamilarasan

2017-01-01

Seed oils are used as cosmetics or topical treatment for wounds, allergy, dandruff, and other purposes. Natural antioxidants from plants were recently reported to delay the onset or progress of various neurodegenerative conditions. Over one thousand cultivars of Punica granatum (Punicaceae) are known and some are traditionally used to treat various ailments. The effect of pomegranate oil on 3-nitropropionic acid- (3-NP) induced cytotoxicity in rat pheochromocytoma (PC12) neuronal cells was analyzed in this study. Furthermore, the analysis of unsaturated fatty acid composition of the seed oil of pomegranate by gas chromatography-electron impact mass spectrometry (GC-MS) was done. GC-MS study showed the presence of 6,9-octadecadiynoic acid (C18:2(6,9)) as a major component (60%) as 4,4-dimethyloxazoline derivative. The total extractable oil with light petroleum ether by Soxhlet from the dry seed of P. granatum was 4-6%. The oil analyzed for 48.90 ± 1.50 mg gallic acid equivalents/g of oil, and demonstrated radical-scavenging-linked antioxidant activities in various in vitro assays like the DPPH (2,2-diphenyl-l-picrylhydrazyl, % IP = 35.2 ± 0.9%), ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), % IP 2.2 ± 0.1%), and β-carotene bleaching assay (% IP = 26 ± 3%), respectively, which could be due the possible role of one methylene interrupted diynoic acid system for its radical-scavenging/antioxidant properties of oil. The oil also reduced lipid peroxidation, suppressed reactive oxygen species, extracellular nitric oxide, lactate/pyruvate ratio, and lactase dehydrogenase generated by 3-NP- (100 mM) induced neurotoxicity in PC12 cells, and enhanced the levels of enzymatic and non-enzymatic antioxidants at 40 μg of gallic acid equivalents. The protective effect of pomegranate seed oil might be due to the ability of an oil to neutralize ROS or enhance the expression of antioxidant gene and the exact mechanism of action yet to be elucidated.

Chemical and amino acid composition of cooked walnut (juglans regia) flour

International Nuclear Information System (INIS)

Niyi, H.; Ogungbenle, N.

2009-01-01

The proximate analysis of cooked walnut (Juglans regia) flour revealed the composition as protein (14.18%), moisture (11.01%), ash (3.14%), crude fibre (3.03%), crude fat (10.22%), carbohydrate (58.42%), phytate (20.18 mg/g), oxalate (1.13 mg/g) and tannin (2.33%). Glutamic and aspartic acids were the most predominant amino acids in the sample with values of 151.6 mg/g and 89.5 mg/g, respectively. (author)

Effect of ocean acidification on the fatty acid composition of a natural plankton community

Science.gov (United States)

Leu, E.; Daase, M.; Schulz, K. G.; Stuhr, A.; Riebesell, U.

2013-02-01

The effect of ocean acidification on the fatty acid composition of a natural plankton community in the Arctic was studied in a large-scale mesocosm experiment, carried out in Kongsfjorden (Svalbard, Norway) at 79° N. Nine mesocosms of ~50 m3 each were exposed to 8 different pCO2 levels (from natural background conditions to ~1420 μatm), yielding pH values (on the total scale) from ~8.3 to 7.5. Inorganic nutrients were added on day 13. The phytoplankton development during this 30-day experiment passed three distinct phases: (1) prior to the addition of inorganic nutrients, (2) first bloom after nutrient addition, and (3) second bloom after nutrient addition. The fatty acid composition of the natural plankton community was analysed and showed, in general, high percentages of polyunsaturated fatty acids (PUFAs): 44-60% of total fatty acids. Positive correlations with pCO2 were found for most PUFAs during phases 2 and/or 3, with the exception of 20:5n3 (eicosapentaenoic acid, EPA), an important diatom marker. These correlations are probably linked to changes in taxonomic composition in response to pCO2. While diatoms (together with prasinophytes and haptophytes) increased during phase 3 mainly in the low and intermediate pCO2 treatments, dinoflagellates were favoured by high CO2 concentrations during the same time period. This is reflected in the development of group-specific fatty acid trophic markers. No indications were found for a generally detrimental effect of ocean acidification on the planktonic food quality in terms of essential fatty acids.

The fatty acid composition of a Vibrio alginolyticus associated with the alga Cladophora coelothrix. Identification of the novel 9-methyl-10-hexadecenoic acid.

Science.gov (United States)

Carballeira, N M; Sostre, A; Stefanov, K; Popov, S; Kujumgiev, A; Dimitrova-Konaklieva, S; Tosteson, C G; Tosteson, T R

1997-12-01

The fatty acid composition of a new strain of Vibrio alginolyticus, found in the alga Cladophora coelothrix, was studied. Among 38 different fatty acids, a new fatty acid, 9-methyl-10-hexadecenoic acid and the unusual 11-methyl-12-octadecenoic acid, were identified. Linear alkylbenzene fatty acids, such as 10-phenyldecanoic acid, 12-phenyldodecanoic acid and 14-phenyltetradecanoic acid, were also found in V. alginolyticus. The alga contained 43% saturated fatty acids, and 28% C16-C20 polyunsaturated fatty acids of the n-3 and n-6 families.

Changes in some physicochemical properties and fatty acid composition of irradiated meatballs during storage

Energy Technology Data Exchange (ETDEWEB)

Gecgel, U., E-mail: ugecgel@nku.edu.tr [Agricultural Faculty, Department of Food Engineering, Namik Kemal University, 59030 Tekirdag (Turkey)

2013-05-15

Meatball samples were irradiated using a {sup 60}Co irradiation source (with the dose of 1, 3, 5 and 7 kGy) and stored (1, 2 and 3 weeks at 4 Degree-Sign C) to appraise some physicochemical properties and the fatty acid composition. The physicochemical results showed no significant differences in moisture, protein, fat and ash content of meatballs because of irradiation. However, total acidity, peroxide and thiobarbituric acid (TBA) values increased significantly as a result of irradiation doses and storage period. The fatty acid profile in meatball samples changed with irradiation. While saturated fatty acids (C16:0, C17:0, C18:0, and C20:0) increased with irradiation, monounsaturated (C14:1, C15:1, C18:1, and C20:1) and polyunsaturated (C18:2, C18:3, and C22:2) fatty acids decreased with irradiation. Trans fatty acids (C16:1trans, C18:1trans, C18:2trans, C18:3trans) increased with increasing irradiation doses. Meatball samples irradiated at 7 kGy had the highest total trans fatty acid content. This research shows that some physicochemical properties and fatty acid composition of meatballs can be changed by gamma irradiation. (author)

Changes in some physicochemical properties and fatty acid composition of irradiated meatballs during storage.

Science.gov (United States)

Gecgel, Umit

2013-06-01

Meatball samples were irradiated using a (60)Co irradiation source (with the dose of 1, 3, 5 and 7 kGy) and stored (1, 2 and 3 weeks at 4°C) to appraise some physicochemical properties and the fatty acid composition. The physicochemical results showed no significant differences in moisture, protein, fat and ash content of meatballs because of irradiation. However, total acidity, peroxide and thiobarbituric acid (TBA) values increased significantly as a result of irradiation doses and storage period. The fatty acid profile in meatball samples changed with irradiation. While saturated fatty acids (C16:0, C17:0, C18:0, and C20:0) increased with irradiation, monounsaturated (C14:1, C15:1, C18:1, and C20:1) and polyunsaturated (C18:2, C18:3, and C22:2) fatty acids decreased with irradiation. Trans fatty acids (C16:1trans, C18:1trans, C18:2trans, C18:3trans) increased with increasing irradiation doses. Meatball samples irradiated at 7 kGy had the highest total trans fatty acid content. This research shows that some physicochemical properties and fatty acid composition of meatballs can be changed by gamma irradiation.

Changes in some physicochemical properties and fatty acid composition of irradiated meatballs during storage

International Nuclear Information System (INIS)

Gecgel, U.

2013-01-01

Meatball samples were irradiated using a 60 Co irradiation source (with the dose of 1, 3, 5 and 7 kGy) and stored (1, 2 and 3 weeks at 4 °C) to appraise some physicochemical properties and the fatty acid composition. The physicochemical results showed no significant differences in moisture, protein, fat and ash content of meatballs because of irradiation. However, total acidity, peroxide and thiobarbituric acid (TBA) values increased significantly as a result of irradiation doses and storage period. The fatty acid profile in meatball samples changed with irradiation. While saturated fatty acids (C16:0, C17:0, C18:0, and C20:0) increased with irradiation, monounsaturated (C14:1, C15:1, C18:1, and C20:1) and polyunsaturated (C18:2, C18:3, and C22:2) fatty acids decreased with irradiation. Trans fatty acids (C16:1trans, C18:1trans, C18:2trans, C18:3trans) increased with increasing irradiation doses. Meatball samples irradiated at 7 kGy had the highest total trans fatty acid content. This research shows that some physicochemical properties and fatty acid composition of meatballs can be changed by gamma irradiation. (author)

Influence of nonylphenol on the fatty acids and hydrocarbon composition of aquatic plants

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І. О. Osinna

2009-11-01

Full Text Available Composition of surface lipids of aquatic plants Acorus calamus L., Typha latifolia L. and Carex acuta L. was investigated under the influence of nonylphenol strong solution. Experimental plants showed some significant changes in the surface lipids composition in comparison with a control. Change in the fatty acids composition, decrease of hydrocarbons content and biosynthetical disorder in the elongation processes of some certain components were revealed.

Fatty acid composition of fish species with different feeding habits from an Arctic Lake.

Science.gov (United States)

Gladyshev, M I; Sushchik, N N; Glushchenko, L A; Zadelenov, V A; Rudchenko, A E; Dgebuadze, Y Y

2017-05-01

We compared the composition and content of fatty acids (FAs) in fish with different feeding habits (sardine (least) cisco Coregonus sardinella, goggle-eyed charr (pucheglazka) form of Salvelinus alpinus complex, humpback whitefish Coregonus pidschian, broad whitefish Coregonus nasus, boganid charr Salvelinus boganidae, and northern pike Esox lucius from an Arctic Lake. Feeding habits of the studied fish (planktivore, benthivore, or piscivore) significantly affected the composition of biomarker fatty acids and the ratio of stable isotopes of carbon and nitrogen in their biomass. The hypothesis on a higher content of eicosapentaenoic and docosahexaenoic acids in the fish of higher trophic level (piscivores) when compared within the same taxonomic group (order Salmoniformes) was confirmed.

Fatty acid composition of leaves of forced chicory (Cichorium intybus L.

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Sinkovič Lovro

2015-01-01

Full Text Available The objective of the present study was to determine the composition of fatty acids in leaves of nine chicory cultivars (Cichorium intybus L.. The growing practice followed the traditional forcing method of developed roots in a peat to obtain new etiolated vegetative apical buds, known as chicons. The fatty acid content was determined by the extraction of fatty acid methyl esters and analysis by means of gas chromatography. The analysis revealed the following ratios of C16:0, C18:0, C18:1, C18:2 and C18:3 of individual fatty acids. The total fatty acid content in forced chicory leaves ranged from 104 to 644 mg/100 g fresh weight. The highest relative content (64% is presented by α-linolenic acid, followed by linoleic (44% and palmitic (21%. An n-6/n-3 polyunsaturated fatty acids ratio of studied forced chicory is below 1.4 and thus, in accordance with the recommended dietary ratio that is close to 1.

Higher acclimation temperature modulates the composition of muscle fatty acid of Tor putitora juveniles

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M.S. Akhtar

2014-08-01

Full Text Available A 30-day acclimation trial was conducted using golden mahseer, Tor putitora juveniles to study its muscle fatty acid composition at five acclimation temperatures (AT. Ninety juveniles of T. putitora were distributed among five treatment groups (20, 23, 26, 29 and 32±0.5 °C. At the end of 30 days trial, highest percentage of monounsaturated fatty acids was found at 20 °C and lowest at 26 °C. The highest percentage of n-6 polyunsaturated fatty acid (PUFA was found at 23 °C and a decreasing trend was observed with increase in AT. However, highest percentage of n-3 PUFA was found at 32 °C and lowest at 29 °C. The maximum n-6 to n-3 ratio was observed at 23 °C and ratio decreased to a minimum at 32 °C. The results revealed that T. putitora juveniles could adapt to higher acclimation temperatures by altering its muscle fatty acid composition mainly by increasing its total saturated fatty acids especially stearic acid.

Changes of Protein and Lipid Contents, Amino Acid and Fatty Acid Compositions in Eggs and Yolk-Sac Larvae of American Shad ( Alosa sapidissima)

Science.gov (United States)

Liu, Zhifeng; Gao, Xiaoqiang; Yu, Jiuxiang; Wang, Yaohui; Guo, Zhenglong; Huang, Bin; Liu, Baoliang; Hong, Lei

2018-04-01

To investigate the changes of the biochemical composition of American shad ( Alosa sapidissima) eggs and larvae at embryonic and early larval stages, samples were collected at different development stages from artificial fertilization to the end of yolk absorption including 2 h, 12 h and 30 h after fertilization and newly hatched larvae including 1 and 3 days after hatching. The composition of lipid, fatty acids, protein and amino acids were analyzed. The content of total protein exhibited a decreasing trend during embryogenesis and larval development, and a significant reduction was detected after hatching ( P acids after hatching except for glycine ( P fatty acids remained stable during the period of embryogenesis. But after hatching, a significant decrease was found in the content of C18:2n-6, C18:3n-6, SFA and ratio of EPA/ARA ( P acids.

Unusual large-pitch banding in poly(L-lactic acid): Effects of composition and geometry confinement

International Nuclear Information System (INIS)

Woo, Eamor M.; Lugito, Graecia; Hsieh, Ya-Ting; Nurkhamidah, Siti

2014-01-01

Lamellar patterns and orientations in blends of two crystalline polymers: poly(ethylene oxide) (PEO) and low-molecular-weight poly(L-lactic acid) (PLLA) were investigated using polarizing light optical microscopy (POM), and atomic and scanning electron microscopy (AFM, SEM). Specific etching off of PEO was used to reveal the complex earlier-grown PLLA lamellae patterns with various PEO content in blends. Banding of extremely long pitch (50 μm) in crystallized PLLA spherulites was induced by two kinetic factors: geometry confinement by top cover and introduction of diluent such as PEO. The mechanisms and correlation among the lamellar assembly, ring bands, and cracks are exemplified. Lamellar patterns and ring-band types in blends were found to vary with respect to not only blend compositions, but also confinement of top-cover

Maximized PUFA measurements improve insight in changes in fatty acid composition in response to temperature

NARCIS (Netherlands)

Van Dooremalen, C.; Pel, R.; Ellers, J.

2009-01-01

A general mechanism underlying the response of ectotherms to environmental changes often involves changes in fatty acid composition. Theory predicts that a decrease in temperature causes an increase in unsaturation of fatty acids, with an important role for long-chain poly-unsaturated fatty acids

Maximized PUFA measurements improve insight in changes in fatty acid composition in response to temperature.

NARCIS (Netherlands)

van Dooremalen, J.A.; Pel, R.; Ellers, J.

2009-01-01

A general mechanism underlying the response of ectotherms to environmental changes often involves changes in fatty acid composition. Theory predicts that a decrease in temperature causes an increase in unsaturation of fatty acids, with an important role for long-chain poly-unsaturated fatty acids

Changes in fatty acid content and composition in silage maize during grain filling

NARCIS (Netherlands)

Khan, N.A.; Cone, J.W.; Pellikaan, W.F.; Khan, M.A.; Struik, P.C.; Hendriks, W.H.

2011-01-01

Background: The stage of maturity at harvest has a major effect on the fatty acid (FA) content and composition of forage plants consumed by dairy cows. The present study investigated the dynamics of FA content and composition in stover (leaves and stem) and ears (cob, shank and husks) of two maize

Visualization of amino acid composition differences between processed protein from different animal species by self-organizing feature maps

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Xingfan ZHOU,Zengling YANG,Longjian CHEN,Lujia HAN

2016-06-01

Full Text Available Amino acids are the dominant organic components of processed animal proteins, however there has been limited investigation of differences in their composition between various protein sources. Information on these differences will not only be helpful for their further utilization but also provide fundamental information for developing species-specific identification methods. In this study, self-organizing feature maps (SOFM were used to visualize amino acid composition of fish meal, and meat and bone meal (MBM produced from poultry, ruminants and swine. SOFM display the similarities and differences in amino acid composition between protein sources and effectively improve data transparency. Amino acid composition was shown to be useful for distinguishing fish meal from MBM due to their large concentration differences between glycine, lysine and proline. However, the amino acid composition of the three MBMs was quite similar. The SOFM results were consistent with those obtained by analysis of variance and principal component analysis but more straightforward. SOFM was shown to have a robust sample linkage capacity and to be able to act as a powerful means to link different sample for further data mining.

Preparation and corrosion resistance of magnesium phytic acid/hydroxyapatite composite coatings on biodegradable AZ31 magnesium alloy.

Science.gov (United States)

Zhang, Min; Cai, Shu; Zhang, Feiyang; Xu, Guohua; Wang, Fengwu; Yu, Nian; Wu, Xiaodong

2017-06-01

In this work, a magnesium phytic acid/hydroxyapatite composite coating was successfully prepared on AZ31 magnesium alloy substrate by chemical conversion deposition technology with the aim of improving its corrosion resistance and bioactivity. The influence of hydroxyapatite (HA) content on the microstructure and corrosion resistance of the coatings was investigated. The results showed that with the increase of HA content in phytic acid solution, the cracks on the surface of the coatings gradually reduced, which subsequently improved the corrosion resistance of these coated magnesium alloy. Electrochemical measurements in simulated body fluid (SBF) revealed that the composite coating with 45 wt.% HA addition exhibited superior surface integrity and significantly improved corrosion resistance compared with the single phytic acid conversion coating. The results of the immersion test in SBF showed that the composite coating could provide more effective protection for magnesium alloy substrate than that of the single phytic acid coating and showed good bioactivity. Magnesium phytic acid/hydroxyapatite composite, with the desired bioactivity, can be synthesized through chemical conversion deposition technology as protective coatings for surface modification of the biodegradable magnesium alloy implants. The design idea of the new type of biomaterial is belong to the concept of "third generation biomaterial". Corrosion behavior and bioactivity of coated magnesium alloy are the key issues during implantation. In this study, preparation and corrosion behavior of magnesium phytic acid/hydroxyapatite composite coatings on magnesium alloy were studied. The basic findings and significance of this paper are as follows: 1. A novel environmentally friendly, homogenous and crack-free magnesium phytic acid/hydroxyapatite composite coating was fabricated on AZ31 magnesium alloy via chemical conversion deposition technology with the aim of enhancing its corrosion resistance and

Identification of Exonic Nucleotide Variants of the Gene Associated with Carcass Traits and Fatty Acid Composition in Korean Cattle

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Dong-yep Oh

2014-10-01

Full Text Available The thyroid hormone responsive protein (THRSP gene is a functional gene that can be used to indicate the fatty acid compositions. This study investigates the relationships of exonic single nucleotide polymorphisms (SNPs in the THRSP gene and fatty acid composition of muscle fat and marbling score in the 612 Korean cattle. The relationships between fatty acid composition and eight SNPs in the THRSP gene (g.78 G>A, g.173 C>T, g.184 C>T, g.190 C>A, g.194 C>T, g.277 C>G, g.283 T>G and g.290 T>G were investigated, and according to the results, two SNPs (g.78 G>A and g.184 C>T in exon 1 were associated with fatty acid composition. The GG and CC genotypes of g.78 G>A and g.184 C>T had higher unsaturated fatty acid (UFA and monounsaturated fatty acid (MUFA content (pA and g.184 C>T had significantly relationships with UFAs and MUFAs. Two SNPs in the THRSP gene affected fatty acid composition, suggesting that GG and CC genotypes and the ht1*ht1 group (Val/Ala haplotype can be markers to genetically improve the quality and flavor of beef.

Photo-oxidation of gaseous ethanol on photocatalyst prepared by acid leaching of titanium oxide/hydroxyapatite composite

Energy Technology Data Exchange (ETDEWEB)

Ono, Y., E-mail: ono-y@kanagawa-iri.go.jp [Mechanical and Material Engineering Division, Kanagawa Industrial Technology Center, Ebina, Kanagawa 243-0435 (Japan); Rachi, T.; Yokouchi, M.; Kamimoto, Y. [Mechanical and Material Engineering Division, Kanagawa Industrial Technology Center, Ebina, Kanagawa 243-0435 (Japan); Nakajima, A. [Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, Meguro, Tokyo 152-8552 (Japan); Okada, K. [Materials and Structures Laboratory, Tokyo Institute of Technology, Midori, Yokohama, Kanagawa 226-8503 (Japan)

2013-06-01

Highlights: ► Photocatalyst powder was prepared by acid leaching of TiO{sub 2}/apatite composite. ► The photocatalytic activity was evaluated from in situ FT-IR study using ethanol. ► Apatite in the composite had positive effect for the photo-oxidation of ethanol. ► The enhanced oxidation rate was explained by the difference in deactivation rate. - Abstract: Highly active photocatalysts were synthesized by leaching of heat-treated titanium dioxide (TiO{sub 2})/hydroxyapatite (HAp) powder with hydrochloric acid at 0.25, 0.50, 0.75 mol/l, and their photocatalytic activities were evaluated from in situ Fourier transform infrared (FT-IR) study of photo-oxidation of gaseous ethanol. By changing the acid concentration, the TiO{sub 2}/HAp composite had different atomic ratios of Ca/Ti (0.0–2.8) and P/Ti (0.3–2.1). It was found that phosphate group remained on the surface of TiO{sub 2} particle even in the sample treated with concentrated acid (0.75 mol/l). These acid-treated samples showed higher rates for ethanol photo-oxidation than the commercial TiO{sub 2} powder, Degussa P25. The highest rate was obtained in the TiO{sub 2}/HAp composite treated with the dilute (0.25 mol/l) acid in spite of its low content of TiO{sub 2} photocatalyst. This enhanced photocatalytic activity was attributed to the result that the deactivation with repeated injections of ethanol gas was suppressed in the TiO{sub 2}/HAp composites compared with the TiO{sub 2} powders.

CRADA Final Report for CRADA No. ORNL99-0544, Interfacial Properties of Electron Beam Cured Composites

Energy Technology Data Exchange (ETDEWEB)

Janke, C.J.

2005-10-17

Electron beam (EB) curing is a technology that promises, in certain applications, to deliver lower cost and higher performance polymer matrix composite (PMC) structures compared to conventional thermal curing processes. PMCs enhance performance by making products lighter, stronger, more durable, and less energy demanding. They are essential in weight- and performance-dominated applications. Affordable PMCs can enhance US economic prosperity and national security. US industry expects rapid implementation of electron beam cured composites in aircraft and aerospace applications as satisfactory properties are demonstrated, and implementation in lower performance applications will likely follow thereafter. In fact, at this time and partly because of discoveries made in this project, field demonstrations are underway that may result in the first fielded applications of electron beam cured composites. Serious obstacles preventing the widespread use of electron beam cured PMCs in many applications are their relatively poor interfacial properties and resin toughness. The composite shear strength and resin toughness of electron beam cured carbon fiber reinforced epoxy composites were about 25% and 50% lower, respectively, than those of thermally cured composites of similar formulations. The essential purpose of this project was to improve the mechanical properties of electron beam cured, carbon fiber reinforced epoxy composites, with a specific focus on composite shear properties for high performance aerospace applications. Many partners, sponsors, and subcontractors participated in this project. There were four government sponsors from three federal agencies, with the US Department of Energy (DOE) being the principal sponsor. The project was executed by Oak Ridge National Laboratory (ORNL), NASA and Department of Defense (DOD) participants, eleven private CRADA partners, and two subcontractors. A list of key project contacts is provided in Appendix A. In order to properly

Small changes in environmental parameters lead to alterations in antibiotic resistance, cell morphology and membrane fatty acid composition in Staphylococcus lugdunensis.

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Marcus J Crompton

Full Text Available Staphylococcus lugdunensis has emerged as a major cause of community-acquired and nosocomial infections. This bacterium can rapidly adapt to changing environmental conditions to survive and capitalize on opportunities to colonize and infect through wound surfaces. It was proposed that S. lugdunensis would have underlying alterations in metabolic homeostasis to provide the necessary levels of adaptive protection. The aims of this project were to examine the impacts of subtle variations in environmental conditions on growth characteristics, cell size and membrane fatty acid composition in S. lugdunensis. Liquid broth cultures of S. lugdunensis were grown under varying combinations of pH (6-8, temperature (35-39°C and osmotic pressure (0-5% sodium chloride w/w to reflect potential ranges of conditions encountered during transition from skin surfaces to invasion of wound sites. The cells were harvested at the mid-exponential phase of growth and assessed for antibiotic minimal inhibitory concentration (MIC, generation time, formation of small colony variants, cell size (by scanning electron microscopy and membrane fatty acid composition. Stress regimes with elevated NaCl concentrations resulted in significantly higher antibiotic resistance (MIC and three of the combinations with 5% NaCl had increased generation times (P<0.05. It was found that all ten experimental growth regimes, including the control and centroid cultures, yielded significantly different profiles of plasma membrane fatty acid composition (P<0.0001. Alterations in cell size (P<0.01 were also observed under the range of conditions with the most substantial reduction occurring when cells were grown at 39°C, pH 8 (514±52 nm, mean ± Standard Deviation compared with cells grown under control conditions at 37°C with pH 7 (702±76 nm, P<0.01. It was concluded that S. lugdunensis responded to slight changes in environmental conditions by altering plasma membrane fatty acid composition

An emerging alternative to thermal curing: Electron curing of fiber-reinforced composites

International Nuclear Information System (INIS)

Singh, A.; Saunders, C.B.; Lopata, V.J.; Kremers, W.; Chung, M.

1995-01-01

Electron curing of fiber-reinforced composites to produce materials with good mechanical properties has been demonstrated by the authors' work, and by Aerospatiale. The attractions of this technology are the technical and processing advantages offered over thermal curing, and the projected cost benefits. Though the work so far has focused on the higher value composites for the aircraft and aerospace industries, the technology can also be used to produce composites for the higher volume industries, such as transportation and automotive

EFFECT OF FERTILIZER ELEMENTS ON LIPIDS ACCUMULATION AND FATTY ACIDS COMPOSITION OF PUMPKIN SEEDS

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S. M. Nadezhkin

2013-01-01

Full Text Available Effect of organic and mineral fertilizers on pumpkin seeds lipids accumulation and their fatty acids com position is investigated. The influence of nutrition's composition on the seeds size, lipids content and concentration of polyunsaturated fatty acids was shown.

[Fatty acid composition of edible marine fish in Zhoushan, Zhejiang province].

Science.gov (United States)

Gao, Yi-xiong; Yue, Bing; Yu, Xin-wei; He, Jia-lu; Shang, Xiao-hong; Li, Xiao-wei; Wu, Yong-ning

2013-06-01

To analyze the main fatty acids in edible marine fish from Zhoushan, Zhejiang province. From September to October 2011, a total of 186 edible marine fish (31 species,6 individual fishes/species) were collected in local markets. Total lipids of edible part were extracted by Folch's method and fatty acids were separated and quantified by gas chromatographic after the homogenization of edible part. The differences of composition of n-6 polyunsaturated fatty acid (n-6 PUFA), n-3 polyunsaturated fatty acid (n-3 PUFA),saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) among fishes were analyzed. Among the 31 fishes, total lipids were highest in Auxis thazard ((13.2 ± 1.2)g/100 g edible part) and lowest in Thamnaconus modestus ((0.6 ± 0.1)g/100 g edible part). Total n-6 PUFA were highest in Mugil cephalus ((875.7 ± 506.4)mg/100 g edible part) and lowest in Seriola quinqueradiata((2.1 ± 1.9)mg/100 g edible part). Total n-3 PUFA were highest in Auxis thazard ((2623.8 ± 426.1)mg/100 g edible part) and lowest in Scoliodon sorrakowah ((82.0 ± 13.9)mg/100 g edible part). SFA were highest in Trachinotus ovatus((3014.9 ± 379.0)mg/100 g edible part) and lowest in Seriola quinqueradiata ((89.7 ± 5.8)mg/100 g edible part). MUFA were highest in Coilia nasus ((3335.7 ± 383.5)mg/100 g edible part) and lowest in Thamnaconus modestus ((32.1 ± 16.9)mg/100 g edible part). There were significant differences of composition of total lipids and of fatty acids among 31 edible marine fish species from Zhoushan.

Preparation and characterization of nano hydroxyapatite/polymeric composites materials. Part I

Energy Technology Data Exchange (ETDEWEB)

Mohamed, Khaled R., E-mail: kh_rezk1966@yahoo.com [Biomaterials Dept., National Research Centre, Dokki, Cairo (Egypt); El-Rashidy, Zenab M. [Biomaterials Dept., National Research Centre, Dokki, Cairo (Egypt); Salama, Aida A. [Biophysics Dept., Faulty of Science, El-Azhar Univ., Cairo (Egypt)

2011-10-17

Highlights: {yields} The formation and coating of CHA increased by increasing polymer content. {yields} The size of the prepared CHA was within nano-range scale. {yields} The composites had homogeneity and CHA formed within the polymeric matrix. - Abstract: The present study is focused on preparation of nano composite materials and the effect of citric acid on their different properties. The formation of nano HA and its interaction with chitosan (C), gelatin (G) polymers and citric acid (CA) materials were studied. The Fourier Transformed Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), transmission electron microscope (TEM), and scanning electron microscope (SEM) were used to characterize these composite materials. The compressive strength (CS) was also measured to know the reinforcement of the prepared composites. The results show that carboxylic and amino groups play crucial role for HA formation on chitosan-gelatin polymeric matrix in the presence of citric acid (CA). The formation of nano HA particles and its average size of crystallite is increased with increase of CG content and decreased with addition of CA. Also, the HA formation and binding strength between its particles are improved into the composites especially with CA. The nano-composites containing the best ratio of nHA (70%) with CA (0.2 M) are promising for medical applications in the future.

Proximate and fatty acid composition of zebra (Equus quagga burchellii) muscle and subcutaneous fat.

Science.gov (United States)

Hoffman, Louwrens C; Geldenhuys, Greta; Cawthorn, Donna-Mareè

2016-08-01

The meat from African game species is healthy, naturally produced and increasingly popular with consumers. Among these species, zebra (Equus quagga burchellii) are growing in number in South Africa, with the meat from surplus animals holding potential to contribute to food security and economic stability. Despite being consumed locally and globally, little information exists on the composition of zebra meat. This study aimed to determine the proximate composition of zebra meat as well as the fatty acid composition of the intramuscular (IMF) and subcutaneous (SCF) fat. Zebra longissimus lumborum muscle was shown to have a high mean protein content (22.29 g per 100 g) and low mean fat content (1.47 g per 100 g). High proportions of polyunsaturated fatty acids (PUFAs) were found in the IMF (41.15%) and SCF (37.71%), mainly comprising α-linolenic (C18:3n-3) and linoleic (C18:2n-6) acids. Furthermore, the IMF and SCF had favourable PUFA/saturated fatty acid ratios (>0.4) and omega-6/omega-3 ratios (<4), indicating that both components are healthy lipid food sources. This study has shed new light on the nutritional value of zebra meat, which will not only be important for food product labelling, nutritional education and incorporation into food composition databases, but will also be indispensable for marketing and export purposes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Healthy n-6/n-3 fatty acid composition from five European game meat species remains after cooking.

Science.gov (United States)

Valencak, Teresa G; Gamsjäger, Lisa; Ohrnberger, Sarah; Culbert, Nicole J; Ruf, Thomas

2015-06-27

Intensive farming of livestock along with recent food scandals and consumer deception have increased awareness about risks for human nutrition. In parallel, the demand for meat obtained under more natural conditions from animals that can freely forage has largely increased. Interestingly, the consumption of game meat has not become more common despite its excellent quality and content of polyunsaturated fatty acids (PUFAs). We addressed the question if game meat fatty acid composition is modified through kitchen preparation. By analysing muscle fatty acid (FA) composition (polar and total lipids) of five European game species in a raw and a processed state, we aimed to quantify the proportion of PUFA that are oxidised and hydrogenated during processing. All game meat species originated from local hunters and free-living individuals. To mimic a realistic situation a professional chef prepared the meat samples with gentle use of heat in a standardised way. Expectedly, the overall content of polyunsaturated fatty acids declined during the cooking process but the decrease size was cooking does not substantially alter its favourable fatty acid composition. Further research is needed to elucidate species-specific differences and the role of habitat quality and locomotion for tissue composition.

Styrene-Assisted Maleic Anhydride Grafted Poly(lactic acid as an Effective Compatibilizer for Wood Flour/Poly(lactic acid Bio-Composites

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Jun Du

2017-11-01

Full Text Available This study aimed to evaluate the effect of styrene-assisted maleic anhydride-grafted poly(lactic acid (PLA-g-St/MAH on the interfacial properties of wood flour/poly(lactic acid (PLA bio-composites. PLA-g-St/MAH was synthesized by free-radical melt grafting using styrene as a comonomer and dicumyl peroxide as an initiator. The structure of PLA-g-St/MAH was characterized by Fourier transform infrared spectroscopy. Wood flour/PLA composites were prepared by compression molding using PLA-g-St/MAH as a compatibilizer. The effects of PLA-g-St/MAH on the rheological and mechanical properties, as well as on the fractured surface morphology of the composites were investigated. Results indicated that storage modulus, complex viscosity, equilibrium torque, and shear heat were significantly increased. The mechanical properties of the wood flour/PLA composites were also significantly increased after the addition of PLA-g-St/MAH. The maximum values were achieved at the loading rate of 3 wt % because of the improved interfacial adhesion between the wood flour and the PLA matrix.

Effect of Exogenous Abscisic Acid and Methyl Jasmonate on Anthocyanin Composition, Fatty Acids, and Volatile Compounds of Cabernet Sauvignon (Vitis vinifera L.) Grape Berries.

Science.gov (United States)

Ju, Yan-Lun; Liu, Min; Zhao, Hui; Meng, Jiang-Fei; Fang, Yu-Lin

2016-10-12

The anthocyanin composition, fatty acids, and volatile aromas are important for Cabernet Sauvignon grape quality. This study evaluated the effect of exogenous abscisic acid (ABA) and methyl jasmonate (MeJA) on the anthocyanin composition, fatty acids, lipoxygenase activity, and the volatile compounds of Cabernet Sauvignon grape berries. Exogenous ABA and MeJA improved the content of total anthocyanins (TAC) and individual anthocyanins. Lipoxygenase (LOX) activity also increased after treatment. Furthermore, 16 fatty acids were detected. The linoleic acid concentration gradually increased with ABA concentration. The fatty acid content decreased with increasing MeJA concentration and then increased again, with the exception of linoleic acid. After exogenous ABA and MeJA treatment, the C6 aroma content increased significantly. Interestingly, the exogenous ABA and MeJA treatments improved mainly the content of 1-hexanol, hexanal, and 2-heptanol. These results provide insight into the effect of plant hormones on wine grapes, which is useful for grape quality improvement.

Effect of Exogenous Abscisic Acid and Methyl Jasmonate on Anthocyanin Composition, Fatty Acids, and Volatile Compounds of Cabernet Sauvignon (Vitis vinifera L. Grape Berries

Directory of Open Access Journals (Sweden)

Yan-Lun Ju

2016-10-01

Full Text Available The anthocyanin composition, fatty acids, and volatile aromas are important for Cabernet Sauvignon grape quality. This study evaluated the effect of exogenous abscisic acid (ABA and methyl jasmonate (MeJA on the anthocyanin composition, fatty acids, lipoxygenase activity, and the volatile compounds of Cabernet Sauvignon grape berries. Exogenous ABA and MeJA improved the content of total anthocyanins (TAC and individual anthocyanins. Lipoxygenase (LOX activity also increased after treatment. Furthermore, 16 fatty acids were detected. The linoleic acid concentration gradually increased with ABA concentration. The fatty acid content decreased with increasing MeJA concentration and then increased again, with the exception of linoleic acid. After exogenous ABA and MeJA treatment, the C6 aroma content increased significantly. Interestingly, the exogenous ABA and MeJA treatments improved mainly the content of 1-hexanol, hexanal, and 2-heptanol. These results provide insight into the effect of plant hormones on wine grapes, which is useful for grape quality improvement.

Optimization of Palmitic Acid Composition in Crude Oleic Acid to Provide Specifications of Titer and Cloud Point of Distillate Oleic Acid using a Flash Distiller

OpenAIRE

Muhammad Yusuf Ritonga

2010-01-01

Titer and cloud point Distilled Oleic Acid’s higher than standard on feed composition palmitic acid (C15H31COOH) or C16 11.2 %. Feed composition C16, top temperature precut and bottom main distiller column were optimized to produce DOA. A factorial design 3 independent variables 3 X 2 X 3, twice repeating’s applied to observe effects of feed composition C16 to quality parameters. On the optimum C16 feed composition at 5.20 % was produced DOA with titer 6.8 oC, cloud point 5.0 oC (inside it...

Fabrication of high conductivity dual multi-porous poly (L-lactic acid)/polypyrrole composite micro/nanofiber film

International Nuclear Information System (INIS)

Yu Qiaozhen; Dai Zhengwei; Lan Ping

2011-01-01

Highlights: → PLLA/H 2 SO 4 -doped PPy composite micro/nano fibers dual multi-pore membranes with high conductivity were fabricated by combining electrospinning with in situ polymerization.These composite fibers have a core-shell structure, the PPy is the core and the PLLA/PPy is the shell. → The size and shape of the pores in this PPy composite fiber membrane can be tuned by polymerization parameters. The largest size of the pores is about 250 μm. → The conductivity of this composite fiber membrane can be adjusted by polymerization parameters. The highest conductivity is 179.0 S cm -1 . The PLLA fibers act as the template in the pyrrole polymerization process and contributed to the increase of the conductivity. - Abstract: Dual multi-porous PLLA (poly(L-lactic acid))/H 2 SO 4 -doped PPy (polypyrrole) composite micro/nano fiber films were fabricated by combining electrospinning with in situ polymerization. The morphologies and structures of the resulting samples were analyzed by scanning electron microscopy (SEM). It was found that the composite micro/nano fibers exhibited a core-shell structure and the composite fiber film had a dual multi-pore structure composed of pores both in the fibers and among the fibers. Semiconductor parameter analyzer was used to characterize the electrical properties of the samples. It was interesting to find that all the PLLA/H 2 SO 4 -doped PPy composite micro/nano fiber films had higher conductivity than H 2 SO 4 -doped PPy particles when the polymerization time up to 180 min. Effects of the pyrrole synthesis conditions on the pore size and the conductivity of PLLA/PPy composite fiber film were assessed. By optimizing the polymerization conditions, the max conductivity of this composite fiber film was about 179.0 S cm -1 with a pore size of about 250 μm. The possible mechanism of PLLA/H 2 SO 4 -doped PPy composite micro/nano fiber films had much higher conductivity than H 2 SO 4 -doped PPy particles was discussed.

A nine-country study of the protein content and amino acid composition of mature human milk

Directory of Open Access Journals (Sweden)

Ping Feng

2016-08-01

Full Text Available Background: Numerous studies have evaluated protein and amino acid levels in human milk. However, research in this area has been limited by small sample sizes and study populations with little ethnic or racial diversity. Objective: Evaluate the protein and amino acid composition of mature (≥30 days human milk samples collected from a large, multinational study using highly standardized methods for sample collection, storage, and analysis. Design: Using a single, centralized laboratory, human milk samples from 220 women (30–188 days postpartum from nine countries were analyzed for amino acid composition using Waters AccQ-Tag high-performance liquid chromatography and total nitrogen content using the LECO FP-528 nitrogen analyzer. Total protein was calculated as total nitrogen×6.25. True protein, which includes protein, free amino acids, and peptides, was calculated from the total amino acids. Results: Mean total protein from individual countries (standard deviation [SD] ranged from 1,133 (125.5 to 1,366 (341.4 mg/dL; the mean across all countries (SD was 1,192 (200.9 mg/dL. Total protein, true protein, and amino acid composition were not significantly different across countries except Chile, which had higher total and true protein. Amino acid profiles (percent of total amino acids did not differ across countries. Total and true protein concentrations and 16 of 18 amino acid concentrations declined with the stage of lactation. Conclusions: Total protein, true protein, and individual amino acid concentrations in human milk steadily decline from 30 to 151 days of lactation, and are significantly higher in the second month of lactation compared with the following 4 months. There is a high level of consistency in the protein content and amino acid composition of human milk across geographic locations. The size and diversity of the study population and highly standardized procedures for the collection, storage, and analysis of human milk support

Plasma lipid fatty acid composition, desaturase activities and insulin sensitivity in Amerindian women.

Science.gov (United States)

Vessby, B; Ahrén, B; Warensjö, E; Lindgärde, F

2012-03-01

Two Amerindian populations--Shuar women living in the Amazonian rain forest under traditional conditions and urbanized women in a suburb of Lima were studied. The fatty acid composition in plasma lipids and the relationships between fatty acid composition and metabolic variables were studied, as well as in a reference group of Swedish women. Fasting plasma was used for analyses of glucose, insulin, leptin and fatty acid composition. Women in Lima had more body fat, higher fasting insulin and leptin and lower insulin sensitivity than the Shuar women, who had insulin sensitivity similar to Swedish women. Shuar women had very high proportions (mean; SD) of palmitoleic (13.2; 3.9%) and oleic (33.9; 3.7%) acids in the plasma cholesteryl esters with very low levels of linoleic acid (29.1; 6.1 3%), as expected on a low fat, high carbohydrate diet. The estimated activity of delta 9 (SCD-1) desaturase was about twice as high in the Shuar compared with Lima women, suggesting neo lipogenesis, while the delta 5 desaturase activity did not differ. The Lima women, as well as the Swedish, showed strong positive correlations between SCD-1 activity on the one hand and fasting insulin and HOMA index on the other. These associations were absent in the Shuar women. The high SCD-1 activity in the Shuar women may reflect increased lipogenesis in adipose tissue. It also illustrates how a low fat diet rich in non-refined carbohydrates can be linked to a good metabolic situation. Copyright © 2010. Published by Elsevier B.V.

Fatty acid composition of lipids in pot marigold (Calendula officinalis L.) seed genotypes.

Science.gov (United States)

Dulf, Francisc V; Pamfil, Doru; Baciu, Adriana D; Pintea, Adela

2013-01-17

Calendula officinalis L. (pot marigold) is an annual aromatic herb with yellow or golden-orange flowers, native to the Mediterranean climate areas. Their seeds contain significant amounts of oil (around 20%), of which about 60% is calendic acid. For these reasons, in Europe concentrated research efforts have been directed towards the development of pot marigold as an oilseed crop for industrial purposes. The oil content and fatty acid composition of major lipid fractions in seeds from eleven genotypes of pot marigold (Calendula officinalis L.) were determined. The lipid content of seeds varied between 13.6 and 21.7 g oil/100 g seeds. The calendic and linoleic acids were the two dominant fatty acids in total lipid (51.4 to 57.6% and 28.5 to 31.9%) and triacylglycerol (45.7 to 54.7% and 22.6 to 29.2%) fractions. Polar lipids were also characterised by higher unsaturation ratios (with the PUFAs content between 60.4 and 66.4%), while saturates (consisted mainly of palmitic and very long-chain saturated fatty acids) were found in higher amounts in sterol esters (ranging between 49.3 and 55.7% of total fatty acids). All the pot marigold seed oils investigated contain high levels of calendic acid (more than 50% of total fatty acids), making them favorable for industrial use. The compositional differences between the genotypes should be considered when breeding and exploiting the pot marigold seeds for nutraceutical and pharmacological purposes.

One-step synthesis of Pt-reduced graphene oxide composites based on high-energy radiation technique

International Nuclear Information System (INIS)

Liu, Xuqiang; Jiang, Shubin; Huang, Wei; Song, Hongtao

2014-01-01

In this paper, we introduce a novel 60 Co-ray-irradiation-based one-step synthesis method of Pt-reduced graphene oxide composites (Pt-RGO) in acid aqueous solution. The compositional distribution of the particles in the samples was characterized by transmission electron microscopy. The structure and composition of the nanocomposite has been determined with a scanning electron microscope (SEM) equipped with an energy dispersion X-ray (EDS) analyzer. Surface enhanced Raman scattering (SERS) of graphene deposited by the Pt nanoparticles were investigated with the 514.5 nm excitation. It was found that small-sized and highly-dispersed Pt nanoparticles could easily grow on the RGO surface under acidic conditions. In addition, the obtained homogeneous dispersions exhibit long-term stability, which will facilitate the production of homogeneous composites. (orig.)

Structural and electronic properties of L-amino acids

Science.gov (United States)

Tulip, P. R.; Clark, S. J.

2005-05-01

The structural and electronic properties of four L-amino acids alanine, leucine, isoleucine, and valine have been investigated using density functional theory (DFT) and the generalized gradient approximation. Within the crystals, it is found that the constituent molecules adopt zwitterionic configurations, in agreement with experimental work. Lattice constants are found to be in good agreement with experimentally determined values, although certain discrepancies do exist due to the description of van der Waals interactions. We find that these materials possess wide DFT band gaps in the region of 5 eV, with electrons highly localized to the constituent molecules. It is found that the main mechanisms behind crystal formation are dipolar interactions and hydrogen bonding of a primarily electrostatic character, in agreement with current biochemical understanding of these systems. The electronic structure suggests that the amine and carboxy functional groups are dominant in determining band structure.

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

Science.gov (United States)

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.

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

International Nuclear Information System (INIS)

Chen Xi; Li Yan; Gu Ning

2010-01-01

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.

Surface analysis of WC--Co composite materials (2) Quantitative Auger electron spectrometry

International Nuclear Information System (INIS)

Tongson, L.L.; Biggers, J.V.; Dayton, G.O.; Bind, J.M.; Knox, B.E.

1978-01-01

The unique sensitivity of Auger electron spectrometry (AES) to combined carbon has been exploited in measuring the surface compositions of hot-pressed, conventionally sintered and mixed powders of WC--Co composite materials. AES sensitivity factors for tungsten and carbon (in WC) relative to cobalt were determined. The concentrations of the major elements in hot-pressed samples measured with AES using the relative sensitivity method were compared to those obtained independently by electron microprobe (EMP) and x-ray fluorescence (XRF) techniques. Corollary studies using ion scattering spectrometry (ISS) showed the absence of (1) matrix effects in the AES measurements, (2) preferential sputtering during ion bombardment, and (3) deposition of the easier-to-sputter component (cobalt) onto WC

Fatty acid and sterol composition of fenugreek seed (Trigonella foenum-graecum L.

Directory of Open Access Journals (Sweden)

Mustafa Kıralan

2017-12-01

Full Text Available Oil content, fatty acid and sterol composition of fenugreek seeds obtained from three different provinces were investigated. Oil was obtained from fenugreek seeds by solvent extraction and oil content was determined between 7.01-8.82%. Fenugreek seed oils were determined to be rich of unsaturated fatty acids according to gas chromatography results. Especially, linoleic acid was the most important of the fatty acids and varied between 45.10-46.19%. Total sterol content of oils varied from 8 681.54 to 9 591.70 ppm. The major sterol was β- sitosterol, and it was found to be between 59.94-68.24% of the total sterols.

High performance bulk metallic glass/carbon nanotube composite cathodes for electron field emission

International Nuclear Information System (INIS)

Hojati-Talemi, Pejman; Gibson, Mark A.; East, Daniel; Simon, George P.

2011-01-01

We report the preparation of new nanocomposites based on a combination of bulk metallic glass and carbon nanotubes for electron field emission applications. The use of bulk metallic glass as the matrix ensures high electrical and thermal conductivity, high thermal stability, and ease of processing, whilst the well dispersed carbon nanotubes act as highly efficient electron emitters. These advantages, alongside excellent electron emission properties, make these composites one of the best reported options for electron emission applications to date.

High performance bulk metallic glass/carbon nanotube composite cathodes for electron field emission

Energy Technology Data Exchange (ETDEWEB)

Hojati-Talemi, Pejman [Department of Materials Engineering, Monash University, Clayton, Vic 3800 (Australia); Mawson Institute, University of South Australia, Mawson Lakes, SA 5095 (Australia); Gibson, Mark A. [Process Science and Engineering, Commonwealth Scientific and Industrial Research Organisation, Clayton, Vic 3168 (Australia); East, Daniel; Simon, George P. [Department of Materials Engineering, Monash University, Clayton, Vic 3800 (Australia)

2011-11-07

We report the preparation of new nanocomposites based on a combination of bulk metallic glass and carbon nanotubes for electron field emission applications. The use of bulk metallic glass as the matrix ensures high electrical and thermal conductivity, high thermal stability, and ease of processing, whilst the well dispersed carbon nanotubes act as highly efficient electron emitters. These advantages, alongside excellent electron emission properties, make these composites one of the best reported options for electron emission applications to date.

Amino acid composition of soybean seeds as affected by climatic variables

Directory of Open Access Journals (Sweden)

Constanza Soledad Carrera

2011-12-01

Full Text Available The objective of this work was to perform a quantitative analysis of the amino acid composition of soybean seeds as affected by climatic variables during seed filling. Amino acids were determined from seed samples taken at harvest in 31 multi-environment field trials carried out in Argentina. Total amino acids ranged from 31.69 to 49.14%, and total essential and nonessential amino acids varied from 12.83 to 19.02% and from 18.86 to 31.15%, respectively. Variance components expressed as the percentage of total variation showed that the environment was the most important source of variation for all traits, followed by the genotype x environment interaction. Significant explanatory linear regressions were detected for amino acid content regarding: average daily mean air temperature and cumulative solar radiation, during seed filling; precipitation minus potential evapotranspiration, during the whole reproductive period; and the combinations of these climatic variables. Each amino acid behaves differently according to environmental conditions, indicating compensatory effects among them.

X-ray photoelectron spectroscopy and Auger electron spectroscopy studies on the passivation behavior of plasma-nitrided low alloy steel in nitric acid

Energy Technology Data Exchange (ETDEWEB)

Chyou, S.D.; Shih, H.C. (Dept. of Materials Science and Engineering, National Tsing Hua Univ., Hsinchu (Taiwan))

1991-12-14

Nitrided SAE 4140 steel has been passivated by concentrated nitric acid. The resulting film was characterized using a combination of surface-analytical techniques, such as X-ray photoelectron spectroscopy (XPS) to evaluate the chemical composition of the passive film. Auger electron spectroscopy (AES) combined with ion etching was used to determine the composition depth profiles of nitrided surface. It was found that preferential dissolution of iron leads to enhanced nitrogen and chromium concentrations within the oxynitrided layer. A dense protective oxynitrided layer was found to be formed on the nitrided surface when the concentration of nitric acid was as high as 8 M. The results of X-ray diffraction, XPS and AES analyses conclude that the protective nitride layer is composed of (Fe,Cr){sub 4}N, (Fe,Cr){sub 2-3}N and CrN in the inner layer, Fe{sub 2}O{sub 3}, Cr{sub 2}O{sub 3} and remnant nitrides in the middle layer and nitrides accompanying Cr(OH){sub 3}.H{sub 2}O and {gamma}'-FeOOH in the outermost layer. (orig.).

Fatty acid composition of subcutaneous and kidney fat depots of ...

African Journals Online (AJOL)

60. Fatty acid composition of subcutaneous and kidney fat depots of Boer goats and the response to varying levels of maize meal. N.H. Casey" and W.A. van Niekerk. Department of Animal Science, Faculty of Agriculture,. University of Pretoria, Pretoria, 0002 Republic of South Africa. xTo whom correspondence should be ...

Properties of poly(lactic acid)/hydroxyapatite composite through the use of epoxy functional compatibilizers for biomedical application.

Science.gov (United States)

Monmaturapoj, Naruporn; Srion, Autcharaporn; Chalermkarnon, Prasert; Buchatip, Suthawan; Petchsuk, Atitsa; Noppakunmongkolchai, Warobon; Mai-Ngam, Katanchalee

2017-08-01

A composite of 70/30 poly(lactic acid)/hydroxyapatite was systematically prepared using various amounts of glycidyl methacrylate as reactive compatibilizer or Joncryl ADR®-4368 containing nine glycidyl methacrylate functions as a chain extension/branching agent to improve the mechanical and biological properties for suitable usage as internal bone fixation devices. The effect of glycidyl methacrylate/Joncryl on mechanical properties of poly(lactic acid)/hydroxyapatite was investigated through flexural strength. Cell proliferation and differentiation of osteoblast-like MC3T3-E1 cells cultured on the composite samples were determined by Alamar Blue assay and alkaline phosphatase expression, respectively. Result shows that flexural strength tends to decrease, as glycidyl methacrylate content increases except for 1 wt.% glycidyl methacrylate. With an addition of dicumyl peroxide, the flexural strength shows an improvement than that of without dicumyl peroxide probably due to the chemical bonding of the hydroxyapatite and poly(lactic acid) as revealed by FTIR and NMR, whereas the composite with 5 wt.% Joncryl shows the best result, as the flexural strength increases getting close to pure poly(lactic acid). The significant morphology change could be seen in composite with Joncryl where the uniform agglomeration of hydroxyapatite particles oriented in poly(lactic acid) matrix. Addition of the epoxy functional compatibilizers at suitable percentages could also have benefits to cellular attachment, proliferation, differentiation and mineralization. So that, this poly(lactic acid)/hydroxyapatite composite could be a promising material to be used as internal bone fixation devices such as screws, pins and plates.

Fatty acid composition of freshwater wild fish in subalpine lakes: a comparative study.

Science.gov (United States)

Vasconi, Mauro; Caprino, Fabio; Bellagamba, Federica; Busetto, Maria Letizia; Bernardi, Cristian; Puzzi, Cesare; Moretti, Vittorio Maria

2015-03-01

In this study, the proximate and fatty acid compositions of the muscle tissue of 186 samples of fish belonging to fifteen species of freshwater fish harvested in subalpine lakes (bleak, shad, crucian carp, whitefish, common carp, pike, black bullhead, burbot, perch, Italian roach, roach, rudd, wels catfish, chub and tench) were investigated. Most of the fish demonstrated a lipid content in the fillet lower than 2.0 g 100 g(-1) wet weight (range 0.6-9.7). A strong relationship between feeding behavior and fatty acid composition of the muscle lipids was observed. Planktivorous fish showed the lowest amounts of n-3 fatty acids (p fish showed the highest amounts of saturated fatty acids and n-3 fatty acids (p fish showed substantial proportions of n-3 fatty acids and the highest contents of n-6 fatty acids. Principal component analysis showed a distinct separation between fish species according to their feeding habits and demonstrated that the most contributing trophic markers were 18:1n-9, 18:3n-3, 22:6n-3 and 20:4n-6. The quantitative amounts n-3 polyunsaturated fatty acid in muscle tissues varied depending on the fish species, the lipid content and the feeding habits. Some species were very lean, and therefore would be poor choices for human consumption to meet dietary n-3 fatty acid requirements. Nevertheless, the more frequently consumed and appreciated fish, shad and whitefish, had EPA and DHA contents in the range 900-1,000 mg 100 g(-1) fresh fillet.

Role of Changes in Cell Fatty Acids Composition in the Increasing of Frost Resistance of Winter Wheat Suspension Culture

Directory of Open Access Journals (Sweden)

I.V. Lyubushkina

2013-11-01

Full Text Available Influences of low temperatures (4 and 8 ° С on the frost tolerance and fatty acid compositions of cells in a winter wheat suspension culture have been studied. It has been found that treatment of the culture with 4 °C (7 days did not protect cells from subsequent freezing temperature action (-8 °С, 6 h and was not accompanied significant changes in the fatty acid composition. On the contrary, the treatment of the culture with the temperature 8 °C (7 days prevented the death caused by freezing temperature and the content of saturated fatty acids decreased: pentadecanoic acid (by 35,0%, palmitic acid (by 19,9% and stearic acid (by 65,4%, and the content of α-linolenic acid increased by 94%. That was the cause of the double bond index (DBI increase by 16%. The role of fatty acids composition changes in the process of increasing frost tolerance in plants are discussed.

Bias voltage effect on electron tunneling across a junction with a ferroelectric–ferromagnetic two-phase composite barrier

International Nuclear Information System (INIS)

Wang Jian; Ju Sheng; Li, Z.Y.

2012-01-01

The effect of bias voltage on electron tunneling across a junction with a ferroelectric–ferromagnetic composite barrier is investigated theoretically. Because of the inversion symmetry breaking of the spontaneous ferroelectric polarization, bias voltage dependence of the electron tunneling shows significant differences between the positive bias and the negative one. The differences of spin filtering or tunnel magnetoresistance increase with the increasing absolute value of bias voltage. Such direction preferred electron tunneling is found intimately related with the unusual asymmetry of the electrical potential profile in two-phase composite barrier and provides a unique change to realize rectifying functions in spintronics. - Highlights: ► Electron tunneling across a ferroelectric–ferromagnetic composite barrier junction. ► TMR effect is different under the same value but opposite direction bias voltage. ► This directionality of the electron tunneling enhances with increasing bias voltage.

Application of electron and Bremsstrahlung beams for composite materials processing

International Nuclear Information System (INIS)

Zalyubovsky, I.I.; Avilov, A.M.; Popov, G.F.; Rudychev, V.G.

1998-01-01

In Kharkiv University the radiation process of obtaining composite polymer materials, CPM, with high strength properties and corrosion resistance was studied. CPM are manufactured by vacuum impregnating capillary-porous materials with synthetic monomers and oligomers or by molding granular waste and resins which are further treated by relativistic electron or Bremsstrahlung beam. Such radiation treatment yields new CPM in which capillary-porous structure acting as reinforcement is filled with polymer. The results of the applied research with industrial electron accelerator in the field of thick CPM formation are presented

PseKRAAC: a flexible web server for generating pseudo K-tuple reduced amino acids composition.

Science.gov (United States)

Zuo, Yongchun; Li, Yuan; Chen, Yingli; Li, Guangpeng; Yan, Zhenhe; Yang, Lei

2017-01-01

The reduced amino acids perform powerful ability for both simplifying protein complexity and identifying functional conserved regions. However, dealing with different protein problems may need different kinds of cluster methods. Encouraged by the success of pseudo-amino acid composition algorithm, we developed a freely available web server, called PseKRAAC (the pseudo K-tuple reduced amino acids composition). By implementing reduced amino acid alphabets, the protein complexity can be significantly simplified, which leads to decrease chance of overfitting, lower computational handicap and reduce information redundancy. PseKRAAC delivers more capability for protein research by incorporating three crucial parameters that describes protein composition. Users can easily generate many different modes of PseKRAAC tailored to their needs by selecting various reduced amino acids alphabets and other characteristic parameters. It is anticipated that the PseKRAAC web server will become a very useful tool in computational proteomics and protein sequence analysis. Freely available on the web at http://bigdata.imu.edu.cn/psekraac CONTACTS: yczuo@imu.edu.cn or imu.hema@foxmail.com or yanglei_hmu@163.comSupplementary information: Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Preparation and Characterization of Composites Based on Polylactic Acid and Beeswax with Improved Water Vapor Barrier Properties.

Science.gov (United States)

Lim, Jung Hoon; Kim, Jeong Ae; Ko, Jung A; Park, Hyun Jin

2015-11-01

Beeswax and a plasticizer (ATBC) were added to polylactic acid (PLA) films in order to enhance the water vapor barrier properties of the films. Beeswax improved the barrier properties; the water vapor permeability in the composite containing 1% beeswax was 58% lower than that of the neat PLA. Fourier transform infrared spectroscopy and X-ray diffraction analysis revealed that the incorporation of beeswax and ATBC had so little effect on the PLA structure. In addition, the structure of PLA did not vary substantially with the additions. The surfaces of the composites were examined by using field emission scanning electron microscopy. Differential scanning calorimetry results showed that the degree of crystallinity of the PLA films increased with the addition of beeswax and ATBC. However, the tensile strength and elongation at break of the composites containing beeswax were up to approximately 50% lower than those of the neat PLA. Although further study is needed to improve the mechanical properties, the aforementioned results showed that the PLA barrier properties can be improved by the incorporation of a small amount of beeswax and ATBC. The results of this study can be applied for the preparation of PLA composite films with improved barrier properties. Such biodegradable films are extremely useful for applications in the food packaging industry. © 2015 Institute of Food Technologists®

Preparation and swelling properties of pH-sensitive composite hydrogel beads based on chitosan-g-poly (acrylic acid)/vermiculite and sodium alginate for diclofenac controlled release.

Science.gov (United States)

Wang, Qin; Xie, Xiaoling; Zhang, Xiaowei; Zhang, Junping; Wang, Aiqin

2010-04-01

A series of pH-sensitive composite hydrogel beads, chitosan-g-poly (acrylic acid)/vermiculite/sodium alginate (CTS-g-PAA/VMT/SA), was prepared using CTS-g-PAA/VMT composite and SA by Ca(2+) as the crosslinking agent. The structure and morphologies of the developed composite hydrogel beads were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. The swelling properties and pH-sensitivity of the beads were investigated. In addition, the drug loading and controlled release behaviors of the beads were also evaluated using diclofenac sodium (DS) as the model drug in stimulated gastric fluids (pH 2.1) and intestinal fluids (pH 6.8). The results indicate that the composite hydrogel beads showed good pH-sensitivity. The release rate of the drug from the composite hydrogel beads is remarkably slowed down, which indicated that incorporating VMT into the composite hydrogel beads can improve the burst release effect of the drug. Copyright 2010 Elsevier B.V. All rights reserved.

Poly(lactic acid Composites Containing Carbon-Based Nanomaterials: A Review

Directory of Open Access Journals (Sweden)

Carolina Gonçalves

2017-07-01

Full Text Available Poly(lactic acid (PLA is a green alternative to petrochemical commodity plastics, used in packaging, agricultural products, disposable materials, textiles, and automotive composites. It is also approved by regulatory authorities for several biomedical applications. However, for some uses it is required that some of its properties be improved, namely in terms of thermo-mechanical and electrical performance. The incorporation of nanofillers is a common approach to attain this goal. The outstanding properties of carbon-based nanomaterials (CBN have caused a surge in research works dealing with PLA/CBN composites. The available information is compiled and reviewed, focusing on PLA/CNT (carbon nanotubes and PLA/GBM (graphene-based materials composites. The production methods, and the effects of CBN loading on PLA properties, namely mechanical, thermal, electrical, and biological, are discussed.

Frying stability of high oleic sunflower oils as affected by composition of tocopherol isomers and linoleic acid content.

Science.gov (United States)

Aladedunye, Felix; Przybylski, Roman

2013-12-01

The influence of linoleic acid content and tocopherol isomeric composition on the frying performance of high oleic sunflower oil was evaluated during a 14-day restaurant style frying operation. At equal linoleic acid content, no significant difference was observed between high oleic sunflower oil containing only α-tocopherol and the sample containing a mixture of α-, γ-, and δ-isomers as measured by the amount of total polar components, oligomers, anisidine value, and free fatty acids. On the contrary, at similar tocopherol isomeric composition, high oleic sunflower oil containing lower amount of linoleic acid showed superior frying stability compared to the sample with a higher content of linoleic acid, suggesting that the frying performance of high oleic sunflower oil is dictated primarily by the level of linoleic acid, with the tocopherol isomeric composition of the oil having no significant influence. In all oil samples, the loss of γ-tocopherol was higher than the corresponding loss of α-tocopherol. Copyright © 2013 Elsevier Ltd. All rights reserved.

Genetic diversity of seed lipid content and fatty acid composition in ...

African Journals Online (AJOL)

Genetic diversity in seed oil content and fatty acid composition in six wild species of genus Sesamum viz., Sesamum mulayanum, Sesamum capense, Sesamum laciniatum, Sesamum latifolium, Sesamum occidentale and Sesamum schinzianum were studied and compared with the cultivated species Sesamum indicum or ...

Towards an organic photobattery - Photovoltaic properties of some thermal copolyamino acids

Science.gov (United States)

Przybylski, A. T.; Syren, R. M.; Fox, S. W.

1983-01-01

Thermal copolymers of amino acids have been examined as a novel material for photovoltaic devices. Due to the steric effects of amino acids during polymerization, these polymers are highly ordered, and pigments such as flavins and pterins are formed as part of the polymer. The controllably varied composition of the amino acids in the polymer makes it possible to get either electron-donor or electron-acceptor, or both kinds of groups in varying degrees. The constituent photosensitive element has been made either of photosensitive polymer film or spherule.

Determination of fatty acid composition of {gamma}-irradiated hazelnuts, walnuts, almonds, and pistachios

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Gecgel, Umit [Namik Kemal University, Agricultural Faculty, Department of Food Engineering, 59030 Tekirdag (Turkey); Gumus, Tuncay; Tasan, Murat; Daglioglu, Orhan; Arici, Muhammet [Namik Kemal University, Agricultural Faculty, Department of Food Engineering, 59030 Tekirdag (Turkey)

2011-04-15

Hazelnut, walnut, almonds, and pistachio nuts were treated with 1, 3, 5, and 7 kGy of gamma irradiation, respectively. Oil content, free fatty acid, peroxide value, and fatty acid composition of the nuts were investigated immediately after irradiation. The data obtained from the experiments indicated that gamma irradiation did not cause any significant change in the oil content of nuts. In contrast, free fatty acid and peroxide value of the nuts increased proportionally to the dose (p<0.05). Among the fatty acids determined, the concentration of total saturated fatty acids increased while total monounsaturated and total polyunsaturated fatty acids decreased with the irradiation dose (p<0.05 and <0.01).

Determination of fatty acid composition of γ-irradiated hazelnuts, walnuts, almonds, and pistachios

International Nuclear Information System (INIS)

Gecgel, Umit; Gumus, Tuncay; Tasan, Murat; Daglioglu, Orhan; Arici, Muhammet

2011-01-01

Hazelnut, walnut, almonds, and pistachio nuts were treated with 1, 3, 5, and 7 kGy of gamma irradiation, respectively. Oil content, free fatty acid, peroxide value, and fatty acid composition of the nuts were investigated immediately after irradiation. The data obtained from the experiments indicated that gamma irradiation did not cause any significant change in the oil content of nuts. In contrast, free fatty acid and peroxide value of the nuts increased proportionally to the dose (p<0.05). Among the fatty acids determined, the concentration of total saturated fatty acids increased while total monounsaturated and total polyunsaturated fatty acids decreased with the irradiation dose (p<0.05 and <0.01).

Determination of fatty acid composition of γ-irradiated hazelnuts, walnuts, almonds, and pistachios

Science.gov (United States)

Gecgel, Umit; Gumus, Tuncay; Tasan, Murat; Daglioglu, Orhan; Arici, Muhammet

2011-04-01

Hazelnut, walnut, almonds, and pistachio nuts were treated with 1, 3, 5, and 7 kGy of gamma irradiation, respectively. Oil content, free fatty acid, peroxide value, and fatty acid composition of the nuts were investigated immediately after irradiation. The data obtained from the experiments indicated that gamma irradiation did not cause any significant change in the oil content of nuts. In contrast, free fatty acid and peroxide value of the nuts increased proportionally to the dose (p<0.05). Among the fatty acids determined, the concentration of total saturated fatty acids increased while total monounsaturated and total polyunsaturated fatty acids decreased with the irradiation dose (p<0.05 and <0.01).

Annealing effects of carbon fiber-reinforced epoxy resin composites irradiated by electron beams

International Nuclear Information System (INIS)

Udagawa, Akira; Sasuga, Tuneo; Ito, Hiroshi; Hagiwara, Miyuki

1987-01-01

Carbon cloth-reinforced epoxy resin composites were irradiated with 2 MeV electrons at room temperature and then annealed in air for 2 h at temperatures up to 180 deg C. A considerable decrease in the three-point bending strength occurred when the irradiated composites were annealed in the temperature range of 115 - 135 deg C which is below the glass transition temperature T g of the matrix resin, while the bending strength remained unchanged up to 180 deg C for the unirradiated composites. In the dynamic viscoelastic spectra of the irradiated matrix, a new relaxation appeared at the temperature extending from 50 deg C to just below the matrix T g and disappeared on annealing for 2 h at 135 deg C. Annealing also decreased the concentration of free radicals existing stably in the irradiated matrix at room temperature. After annealing, a large amount of clacks and voids were observed in the fractography of the composites by scanning electron microscopy. These results indicate: (1) Annealing brings about rearrangement of the radiation-induced molecular chain scission in the matrix; (2) The bending strength of the irradiated composites decreased owing to the increased brittleness of the matrix by annealing. (author)

Tannin, protein contents and fatty acid compositions of the seeds of several Vicia L. species from Turkey

OpenAIRE

Kökten, Kağan; Koçak, Alpaslan; Bağci, Eyüp; Akçura, Mevlüt; Çelik, Sait

2010-01-01

The seedoils of six Vicia species (Leguminosae) were investigated for their protein, tannin contents and fatty acid compositions. The protein contents of the seeds were found to be between 21.87%-31.33%. The tannin contents of the seeds were found to be between 0.13%-1.07%. The fatty acid compositions of these six different species were determined by the GC of the methyl esters of their fatty acids. The oilseeds of Vicia species contain palmitic and stear...

Effect of the fatty acid composition of acclimated oenological Lactobacillus plantarum on the resistance to ethanol.

Science.gov (United States)

Bravo-Ferrada, B M; Gómez-Zavaglia, A; Semorile, L; Tymczyszyn, E E

2015-02-01

The aim of this work was to evaluate the changes due to acclimation to ethanol on the fatty acid composition of three oenological Lactobacillus plantarum strains and their effect on the resistance to ethanol and malic acid consumption (MAC). Lactobacillus plantarum UNQLp 133, UNQLp 65.3 and UNQLp 155 were acclimated in the presence of 6 or 10% v/v ethanol, for 48 h at 28°C. Lipids were extracted to obtain fatty acid methyl esters and analysed by gas chromatography interfaced with mass spectroscopy. The influence of change in fatty acid composition on the viability and MAC in synthetic wine was analysed by determining the Pearson correlation coefficient. Acclimated strains showed a significant change in the fatty composition with regard to the nonacclimated strains. Adaptation to ethanol led to a decrease in the unsaturated/saturated ratio, mainly resulting from an increase in the contribution of short-length fatty acid C12:0 and a decrease of C18:1. The content of C12:0 was related to a higher viability after inoculation of synthetic wine. The MAC increased at higher contents in saturated fatty acid, but its efficiency was strain dependent. © 2014 The Society for Applied Microbiology.

Increase in electron mobility of InGaAs/InP composite channel high electron mobility transistor structure due to SiN passivation

International Nuclear Information System (INIS)

Liu Yuwei; Wang Hong; Radhakrishnan, K.

2007-01-01

The influence of silicon nitride passivation on electron mobility of InGaAs/InP composite channel high electron mobility transistor structure has been studied. Different from the structures with single InGaAs channel, an increase in effective mobility μ e with a negligible change of sheet carrier density n s after SiN deposition is clearly observed in the composite channel structures. The enhancement of μ e could be explained under the framework of electrons transferring from the InP sub-channel into InGaAs channel region due to the energy band bending at the surface region caused by SiN passivation, which is further confirmed by low temperature photoluminescence measurements

Thermal and mechanical interfacial properties of epoxy composites based on functionalized carbon nanotubes

International Nuclear Information System (INIS)

Jin Fanlong; Ma Changjie; Park, Soo-Jin

2011-01-01

Highlights: → CNTs were functionalized by acid and amine treatments. → Epoxy resin/CNT composites were prepared. → T g of the composites increased by about 10 deg. C compared to neat epoxy resins. → Toughness of the composites was significantly improved by the addition of functionalized CNTs. - Abstract: Carbon nanotubes (CNTs) were treated by a mixture of acid and functionalized subsequently by amine treatment to improve interfacial interactions and dispersion of CNTs in epoxy matrix. The thermal stabilities and mechanical interfacial properties of epoxy/CNT composites were investigated using several techniques. The dispersion state of CNTs in the epoxy matrix was observed by scanning electron microscope (SEM) and transmission electron microscopy (TEM). As a result, the glass transition temperature of epoxy/CNT composites increased by about 11 deg. C compared to neat epoxy resins. The mechanical interfacial property of the composites was significantly increased by the addition of amine treated CNTs. The SEM and TEM results showed that the separation and uniform dispersion of CNTs in the epoxy matrix.

Fatty acid composition of maize germ oil from high-oil hybrids wet-milling processing

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Jovanović Petar Lj.

2005-01-01

Full Text Available Maize germ was obtained by wet-milling laboratory processing of domestic high-oil maize hybrids. After separation, the germ was subjected to extraction of maize oil. Fatty acid composition of maize germ oil was determined by gas chromatography. The results showed very high levels of unsaturated fatty acids and a constant sum of oleic and linoleic acids in oils of different maize hybrids.

Characterization of Fatty Acid Composition in Bone Marrow Fluid From Postmenopausal Women: Modification After Hip Fracture.

Science.gov (United States)

Miranda, Melissa; Pino, Ana María; Fuenzalida, Karen; Rosen, Clifford J; Seitz, Germán; Rodríguez, J Pablo

2016-10-01

Bone marrow adipose tissue (BMAT) is associated with low bone mass, although the functional consequences for skeletal maintenance of increased BMAT are currently unclear. BMAT might have a role in systemic energy metabolism, and could be an energy source as well as an endocrine organ for neighboring bone cells, releasing cytokines, adipokines and free fatty acids into the bone marrow microenvironment. The aim of the present report was to compare the fatty acid composition in the bone marrow supernatant fluid (BMSF) and blood plasma of postmenopausal women women (65-80 years old). BMSF was obtained after spinning the aspirated bone marrow samples; donors were classified as control, osteopenic or osteoporotic after dual-energy X-ray absorptiometry. Total lipids from human bone marrow fluid and plasma were extracted, converted to the corresponding methyl esters, and finally analyzed by a gas chromatographer coupled with a mass spectrometer. Results showed that fatty acid composition in BMSF was dynamic and distinct from blood plasma, implying significance in the locally produced lipids. The fatty acid composition in the BMSF was enriched in saturated fatty acid and decreased in unsaturated fatty acids as compared to blood plasma, but this relationship switched in women who suffered a hip fracture. On the other hand, there was no relationship between BMSF and bone mineral density. In conclusion, lipid composition of BMSF is distinct from the circulatory compartment, most likely reflecting the energy needs of the marrow compartment. J. Cell. Biochem. 117: 2370-2376, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Mapping quantitative trait loci (QTLs for fatty acid composition in an interspecific cross of oil palm

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Sharma Mukesh

2009-08-01

Full Text Available Abstract Background Marker Assisted Selection (MAS is well suited to a perennial crop like oil palm, in which the economic products are not produced until several years after planting. The use of DNA markers for selection in such crops can greatly reduce the number of breeding cycles needed. With the use of DNA markers, informed decisions can be made at the nursery stage, regarding which individuals should be retained as breeding stock, which are satisfactory for agricultural production, and which should be culled. The trait associated with oil quality, measured in terms of its fatty acid composition, is an important agronomic trait that can eventually be tracked using molecular markers. This will speed up the production of new and improved oil palm planting materials. Results A map was constructed using AFLP, RFLP and SSR markers for an interspecific cross involving a Colombian Elaeis oleifera (UP1026 and a Nigerian E. guinneensis (T128. A framework map was generated for the male parent, T128, using Joinmap ver. 4.0. In the paternal (E. guineensis map, 252 markers (199 AFLP, 38 RFLP and 15 SSR could be ordered in 21 linkage groups (1815 cM. Interval mapping and multiple-QTL model (MQM mapping (also known as composite interval mapping, CIM were used to detect quantitative trait loci (QTLs controlling oil quality (measured in terms of iodine value and fatty acid composition. At a 5% genome-wide significance threshold level, QTLs associated with iodine value (IV, myristic acid (C14:0, palmitic acid (C16:0, palmitoleic acid (C16:1, stearic acid (C18:0, oleic acid (C18:1 and linoleic acid (C18:2 content were detected. One genomic region on Group 1 appears to be influencing IV, C14:0, C16:0, C18:0 and C18:1 content. Significant QTL for C14:0, C16:1, C18:0 and C18:1 content was detected around the same locus on Group 15, thus revealing another major locus influencing fatty acid composition in oil palm. Additional QTL for C18:0 was detected on Group 3

Fatty acid composition and natural antioxidant capacity of ten Serbian linseed cultivars

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Čolović Dušica S.

2015-01-01

Full Text Available Literature data about nutritional characteristics of linseed cultivars from some specific geographical area or country is scarce. For that very reason, following paper is presenting fatty acid (FA compositions and antioxidant capacity of lipid-soluble (ACL components of ten native linseed cultivars from Serbia. These characteristics can be interesting, especially due to the increasing trend of linseed usage in human diet. Presented results show that there were statistically significant (p<0.05 differences between linseed kernels in FA composition. Negative correlation was found between FA C18:0 and α-linolenic acid (ALA. The cultivar with the highest ACL value was No. 10 (342.66 μmol trolox/kg d.m., meaning that it had very strong protection against oxidation of polyunsaturated FAs. Nevertheless, correlation between ACL and polyunsaturated FA content in cultivars was not statistically significant (p=0.84. ACL of the samples did not depend on FA composition of linseed, but it might depend on characteristics of a specific cultivar. The aforementioned results show potential usage in storage of linseeds or its products, while FA composition of linseed kernels might be one of criteria for authentication of linseed origin, and can be of great help in future selection of the cultivars, depending on purpose of linseed production.

Fatty acid composition and its association with chemical and sensory analysis of boar taint.

Science.gov (United States)

Liu, Xiaoye; Trautmann, Johanna; Wigger, Ruth; Zhou, Guanghong; Mörlein, Daniel

2017-09-15

A certain level of disagreement between the chemical analysis of androstenone and skatole and the human perception of boar taint has been found in many studies. Here we analyze whether the fatty acid composition can explain such inconsistency between sensory evaluation and chemical analysis of boar taint compounds. Therefore, back fat samples (n=143) were selected according to their sensory evaluation by a 10-person sensory panel, and the chemical analysis (stable isotope dilution analysis with headspace solid-phase microextraction and gas chromatography-mass spectrometry) of androstenone and skatole. Subsequently a quantification of fatty acids using gas chromatography-flame ionization detection was conducted. The correlation analyses revealed that several fatty acids are significantly correlated with androstenone, skatole, and the sensory rating. However, multivariate analyses (principal component analysis) revealed no explanation of the fatty acid composition with respect to the (dis-)agreement between sensory and chemical analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Amino acid composition of the bushcricket spermatophore and the function of courtship feeding: Variable composition suggests a dynamic role of the nuptial gift.

Science.gov (United States)

Jarrige, Alicia; Body, Mélanie; Giron, David; Greenfield, Michael D; Goubault, Marlène

2015-11-01

Nuptial gifts are packages of non-gametic material transferred by males to females at mating. These gifts are common in bushcrickets, where males produce a complex spermatophore consisting in a sperm-containing ampulla and an edible sperm-free spermatophylax. Two non-mutually exclusive hypotheses have been suggested to explain the function of the spermatophylax: the paternal investment hypothesis proposes that it represents a male nutritional investment in offspring; the mating effort hypothesis proposes that the spermatophylax maximizes the male's sperm transfer. Because gift production may represent significant energy expenditure, males are expected to adjust their investment relative to the perceived quality of the female. In this study, we first examined the free amino acid composition and protein-bound amino acid composition of the nuptial gift in the bushcricket, Ephippiger diurnus (Orthoptera: Tettigoniidae). Second, we investigated whether this composition was altered according to female age and body weight. Our study represents the first investigation of both free and protein-bound amino acid fractions of a bushcricket spermatophylax. We found that composition of the nuptial gift varied both qualitatively and quantitatively with respect to traits of the receiving female: older females received larger amounts of protein-bound amino acids (both essential and non-essential), less water and less free glycine. This result suggests that gift composition is highly labile in E. diurnus, and we propose that gift allocation might represent a form of cryptic male mate choice, allowing males to maximize their chances of paternity according to the risk of sperm competition that is associated with mate quality. Copyright © 2015 Elsevier Inc. All rights reserved.

Synthesis and characterization of Cerium-doped hydroxyapatite/polylactic acid composite coatings on metal substrates

Energy Technology Data Exchange (ETDEWEB)

Yuan, Qiuhua, E-mail: yuanqiuh@szu.edu.cn; Qin, Caoping; Wu, Jianbo; Xu, Anping; Zhang, Ziqiang; Liao, Junquan; Lin, Songxin; Ren, Xiangzhong; Zhang, Peixin

2016-10-01

Ce-doped hydroxyapatite/polylactic acid (HA/PLA) composites serving as implant coatings have rarely been studied by other researchers in recent years. This paper was focused to study the existence of Ce ions in structure, chemical composition and surface morphology of HA and its composite coatings. Ce-doped HA powders were synthesized by chemical precipitation method with different Ce molar fractions (0(pure HA), 0.5 mol%, 1 mol% and 2 mol%). And Ce-doped HA/PLA composite coatings were fabricated for the first time on stainless steel substrates by spin coating technique. The obtained samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) coupled with energy dispersive X-ray detector (EDX), thermo gravimetric-differential thermal analysis (TG-DTA) and X-ray photoelectron spectroscopy (XPS). The results showed that Ce ions were doped into the crystal lattice of apatite successfully. The (Ce + Ca)/P atomic ratios in the doped HA/PLA samples ranged from 1.614 to 1.673, which were very close to the theoretical value of 1.67 for the stoichiometric HA. The addition of PLA could keep metal substrates from catalyzing the decomposition of HA. TG-DTA analysis indicated that Ce-doped HA powder had high thermal stability, and the SEM micrographs revealed that the surface topography of Ce-doped HA/PLA composite coatings was uniform and dense when the Ce molar fraction was 2 mol%. XPS results indicated that the Ce ions doped in HA showed mixed valences of Ce{sup 3+} and Ce{sup 4+}. - Highlights: • Ce-doped HA composite coatings were synthesized by spin-coating technique for the first time. • Ce ions were demonstrated to dope into HA crystal lattice successfully. • The addition of PLA could keep metal substrates from catalyzing the decomposition of HA. • XPS results showed that Ce ions doped in HA have mixed valences of Ce{sup 3+} and Ce{sup 4+}.

In vitro and in vivo evaluation of polylactic acid-based composite with tricalcium phosphate microsphere for enhanced biodegradability and osseointegration.

Science.gov (United States)

Shin, Da Yong; Kang, Min-Ho; Kang, In-Gu; Kim, Hyoun-Ee; Jeong, Seol-Ha

2018-05-01

A biodegradable polylactic acid composite containing tricalcium phosphate microsphere was fabricated. The composite exhibited enhanced biocompatibility and a well-interconnected porous structure that enabled tissue ingrowth after degradation. The tricalcium phosphate microspheres had an average size of 106 ± 43 μm and were incorporated into the polylactic acid matrix using a high-shear mixer. The resulting bioactivity and hydrophilicity were enhanced to levels comparable to those of a polylactic acid composite containing tricalcium phosphate powder, which is a well-known material used in the medical field. An accelerated 30-day degradation test in HCl revealed successful generation of an open porous structure with ∼98% interconnectivity in the polylactic acid-tricalcium phosphate microsphere composite, demonstrating the potential of this material to induce enhanced osseointegration in the later stage of bone regeneration. The early stage osseointegration was also evaluated by implanting the composite in vivo using a rabbit femoral defect model. After 16 weeks of implantation, the bone-to-implant contact ratio of the polylactic acid-tricalcium phosphate microsphere composite was enhanced owing to tissue ingrowth through the generated pores near the surface.

Effect of ocean acidification on the fatty acid composition of a natural plankton community

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E. Leu

2013-02-01

Full Text Available The effect of ocean acidification on the fatty acid composition of a natural plankton community in the Arctic was studied in a large-scale mesocosm experiment, carried out in Kongsfjorden (Svalbard, Norway at 79° N. Nine mesocosms of ~50 m³ each were exposed to 8 different pCO₂ levels (from natural background conditions to ~1420 μatm, yielding pH values (on the total scale from ~8.3 to 7.5. Inorganic nutrients were added on day 13. The phytoplankton development during this 30-day experiment passed three distinct phases: (1 prior to the addition of inorganic nutrients, (2 first bloom after nutrient addition, and (3 second bloom after nutrient addition. The fatty acid composition of the natural plankton community was analysed and showed, in general, high percentages of polyunsaturated fatty acids (PUFAs: 44–60% of total fatty acids. Positive correlations with pCO₂ were found for most PUFAs during phases 2 and/or 3, with the exception of 20:5n3 (eicosapentaenoic acid, EPA, an important diatom marker. These correlations are probably linked to changes in taxonomic composition in response to pCO₂. While diatoms (together with prasinophytes and haptophytes increased during phase 3 mainly in the low and intermediate pCO₂ treatments, dinoflagellates were favoured by high CO₂ concentrations during the same time period. This is reflected in the development of group-specific fatty acid trophic markers. No indications were found for a generally detrimental effect of ocean acidification on the planktonic food quality in terms of essential fatty acids.

Fatty acid composition of lipids in pot marigold (Calendula officinalis L. seed genotypes