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Sample records for high cellulose content

  1. Strong and moldable cellulose magnets with high ferrite nanoparticle content.

    Science.gov (United States)

    Galland, Sylvain; Andersson, Richard L; Ström, Valter; Olsson, Richard T; Berglund, Lars A

    2014-11-26

    A major limitation in the development of highly functional hybrid nanocomposites is brittleness and low tensile strength at high inorganic nanoparticle content. Herein, cellulose nanofibers were extracted from wood and individually decorated with cobalt-ferrite nanoparticles and then for the first time molded at low temperature (ferrite and cellulose material. A nanocomposite with 70 wt % ferrite, 20 wt % cellulose nanofibers, and 10 wt % epoxy showed a modulus of 12.6 GPa, a tensile strength of 97 MPa, and a strain at failure of ca. 4%. Magnetic characterization was performed in a vibrating sample magnetometer, which showed that the coercivity was unaffected and that the saturation magnetization was in proportion with the ferrite content. The used ferrite, CoFe2O4, is a magnetically hard material, demonstrated by that the composite material behaved as a traditional permanent magnet. The presented processing route is easily adaptable to prepare millimeter-thick and moldable magnetic objects. This suggests that the processing method has the potential to be scaled-up for industrial use for the preparation of a new subcategory of magnetic, low-cost, and moldable objects based on cellulose nanofibers.

  2. ECOLOGY SAFE METHOD OF OBTAINING FROM FIR-WOOD THE CELLULOSIC PRODUCT WITH HIGH CONTENT OF ALFA-CELLULOSE

    OpenAIRE

    Владимир Александрович Левданский; Александр Владимирович Левданский; Борис Николаевич Кузнецов

    2014-01-01

    The «green» method of obtaining from fir-wood the cellulosic product with high content of alpha-cellulose was developed. It consists of the stage of wood delignification by hydrogen peroxide in the medium «acetic acid – water – sulfuric acid catalyst» and of the stage of alkaline treatment by NaOH. Preparation conditions were selected which allow to obtain with an acceptable yield (30–31% mas.) the cellulosic product containing 97,3–98,0% mas. of alpha-cellulose.

  3. Protein adsorption of dialdehyde cellulose-crosslinked chitosan with high amino group contents.

    Science.gov (United States)

    Kim, Ung-Jin; Lee, Yeong Ro; Kang, Tong Ho; Choi, Joon Weon; Kimura, Satoshi; Wada, Masahisa

    2017-05-01

    Crosslinked chitosan was prepared by Schiff base formation between the aldehyde groups of dialdehyde cellulose (DAC) and the amino groups of chitosan and a subsequent reduction. DAC was obtained through periodate oxidation of cellulose and solubilization in hot water at 100°C for 1h. Three grades of DAC-crosslinked chitosan were prepared by adding various amounts DAC. The degrees of crosslinking as determined by amino group content were 3.8, 8.3, and 12.1%, respectively. DAC-crosslinked chitosan showed higher stability in the pH 2-9 range and no cytotoxicity was identified over the course of a 21-day long-term stability test. Also, DAC-crosslinked chitosan showed remarkably high bovine serum albumin (BSA) adsorption capacity at pH 5.5 as a result of the increased amino group content, due to the reaction between DAC and chitosan molecular chains occurring at multiple points even though DAC-crosslinked chitosan showed a lower degree of crosslinking.

  4. Nanocrystalline cellulose with various contents of sulfate groups.

    Science.gov (United States)

    Voronova, M I; Surov, O V; Zakharov, A G

    2013-10-15

    Properties of films derived from aqueous nanocrystalline cellulose dispersions by water evaporation depend on concentration of sulfate groups. Namely type of thermodestruction and surface morphology change as a function of contents of sulfate groups. Surface roughness increases and water adsorption enhances with increasing sulfate groups content particularly at high relative pressure.

  5. Potential approaches to improve gasification of high water content biomass rich in cellulose in dual fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Li; Xu, Guangwen [State Key Laboratory of Multiphase Complex System, Institute of Process Engineering, Chinese Academy of Sciences, Beijing (China); Suda, Toshiyuki [Research Laboratory, IHI Corporation, Ltd., Yokohama (Japan); Murakami, Takahiro [National Institute of Advanced Science and Technology, Tsukuba (Japan)

    2010-08-15

    Biomass containing water of 30-65 wt.% and rich in cellulose, such as various grounds of drinking materials and the lees of spirit and vinegar, is not suitable for biological digestion, and the thermal conversion approach has to be applied to its conversion into bioenergy. The authors have recently worked on converting such biomass into middle heating-value gas via dual fluidized bed gasification (DFBG) integrated with various process intensification technologies. This article is devoted to highlighting those technical ways, including the choice of the superior technical deployment for a DFBG system, the impregnation of Ca onto fuel in fuel drying, the integration of gas cleaning with fuel gasification via two-stage DFBG (T-DFBG), and the decoupling of fuel drying/pyrolysis and char gasification via the decoupled DFBG (D-DFBG). The attained results demonstrated that the superior deployment of bed combination for the DFBG should be a bubbling/turbulent fluidized bed gasifier integrated with a pneumatic riser combustor. In terms of improving efficiency of fuel conversion into combustible gas and suppressing tar generation during gasification, the impregnation of Ca onto fuel exhibited distinctively high upgrading effect, while both the T-DFBG and D-DFBG were also demonstrated to be effective to a certain degree. (author)

  6. Oxidized Cellulose with Different Carboxyl Content: Structure and Properties before and after Beating

    Science.gov (United States)

    Vendula, Hejlová; Miloslav, Milichovský

    Our recent studies concentrated in investigating influence of beating oxidized cellulose, with different carboxyl content, on changing their basic properties (degree of polymerization, WRV - water resistant value and X-ray diffraction). Cellulose samples of oxidized cellulose were beated by toroidal beating machine. Cellulose consists of both amorphous and crystalline regions. Cellulose consists of linear chains of poly[ß-1,4-D- anhydroglucopyranose] (C6nH10n + 2O5n + 1 (n = degree of polymerization of glucose)), which crystallize through hydrogen bonding between the chains and has cellobiose as repeat unit. Oxidized cellulose is preparing by oxidation of cellulose in the C6 position of the glucopyranose units to carboxylic group (-COOH) and polyanhydroglukuronic acid (PAGA) is arised. An other option is oxidation with sodium hypochlorite with catalytic amounts of sodium bromide and 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) under various conditions. Beating and refining or mechanical treatment of fibers in water is an important step in using pulps for papermaking. It is an energy intensive process. The purpose of the treatment is to modify fiber properties to obtain the most desirable paper machine runnability and product properties. End of beating pulps was characterized by position, when all beated pulps under mixture passed through of riddle (about sizes mesh of 50). During beating of samples about different ratio of oxidation it was found, that samples with higher contents of COOH groups in starting pulp are characterized by a significantly lower specific beating energy consumption needed to achieving the same sizes of particles. X-ray analyse shows that for non-beated oxidized cellulose was perceptible high share amorphous contents compared with beated oxidized cellulose.

  7. High Performance Regenerated Cellulose Membranes from Trimethylsilyl Cellulose

    KAUST Repository

    Ali, Ola

    2013-05-01

    Regenerated cellulose (RC) membranes are extensively used in medical and pharmaceutical separation processes due to their biocompatibility, low fouling tendency and solvent resistant properties. They typically possess ultrafiltration and microfiltration separation characteristics, but recently, there have been attempts to widen their pool of applications in nanofiltration processes. In this work, a novel method for preparing high performance composite RC membranes was developed. These membranes reveal molecular weight cut-offs (MWCO) of less than 250 daltons, which possibly put them ahead of all commercial RC membranes and in competition with high performance nanofiltration membranes. The membranes were prepared by acidic hydrolysis of dip-coated trimethylsilyl cellulose (TMSC) films. TMSC, with a degree of silylation (DS) of 2.8, was prepared from microcrystalline cellulose by reaction with hexamethyldisilazane under the homogeneous conditions of LiCl/DMAC solvent system. Effects of parameters, such as coating solution concentration and drying rates, were investigated. It was concluded that higher TMSC concentrations as well as higher solvent evaporation rates favor better MWCOs, mainly due to increase in the selective layer thickness. Successful cross-linking of prepared membranes with glyoxal solutions, in the presence of boric acid as a catalyst, resulted in MWCOs less than 250 daltons. The suitability of this crosslinking reaction for large scale productions was already proven in the manufacturing of durable-press fabrics. For us, the inexpensive raw materials as well as the low reaction times and temperatures were of interest. Moreover, the non-toxic nature of glyoxal is a key advantage in medical and pharmaceutical applications. The membranes prepared in this work are strong candidates for separation of small organic solutes from organic solvents streams in pharmaceutical industries. Their hydrophilicity, compared to typical nanofiltration membranes, offer

  8. Tunable Semicrystalline Thin Film Cellulose Substrate for High-Resolution, In-Situ AFM Characterization of Enzymatic Cellulose Degradation.

    Science.gov (United States)

    Ganner, Thomas; Roŝker, Stephanie; Eibinger, Manuel; Kraxner, Johanna; Sattelkow, Jürgen; Rattenberger, Johannes; Fitzek, Harald; Chernev, Boril; Grogger, Werner; Nidetzky, Bernd; Plank, Harald

    2015-12-23

    In the field of enzymatic cellulose degradation, fundamental interactions between different enzymes and polymorphic cellulose materials are of essential importance but still not understood in full detail. One technology with the potential of direct visualization of such bioprocesses is atomic force microscopy (AFM) due to its capability of real-time in situ investigations with spatial resolutions down to the molecular scale. To exploit the full capabilities of this technology and unravel fundamental enzyme-cellulose bioprocesses, appropriate cellulose substrates are decisive. In this study, we introduce a semicrystalline-thin-film-cellulose (SCFTC) substrate which fulfills the strong demands on such ideal cellulose substrates by means of (1) tunable polymorphism via variable contents of homogeneously sized cellulose nanocrystals embedded in an amorphous cellulose matrix; (2) nanoflat surface topology for high-resolution and high-speed AFM; and (3) fast, simple, and reproducible fabrication. The study starts with a detailed description of SCTFC preparation protocols including an in-depth material characterization. In the second part, we demonstrate the suitability of SCTFC substrates for enzymatic degradation studies by combined, individual, and sequential exposure to TrCel6A/TrCel7A cellulases (Trichoderma reesei) to visualize synergistic effects down to the nanoscale.

  9. Modification of cellulose for high glucose generation.

    Science.gov (United States)

    Jiang, Xue; Gu, Jian; Tian, Xiuzhi; Li, Yali; Huang, Dan

    2012-01-01

    The influence of introduction of cyanuric chloride on glucose's yield (Y) in acid-catalyzed hydrolysis of microcrystalline cellulose (MCC) has been studied. The content of cyanuric chloride (C) in modified MCCs was determined by X-ray photoelectric spectroscopy. The chemical structures of modified MCCs were analyzed by Fourier transformation-infrared spectroscopy and cross polarization/magic angle spinning (13)C nuclear magnetic resonance. Crystal index (CI) and the ratio (R) representing the sum of content of (1 ̅10) and (110) to that of (200) were calculated based on diffraction intensity in wide angle X-ray diffraction (WAXD). Hydrolysis experiment and WAXD show that Y, CI and R vary with C. The modified MCC containing 3.9 mol% of cyanuric chloride has the highest Y, the highest R and the lowest CI. Variations of CI and R show that the chemical modification changed the proportion of crystal/amorphous and crystal planes, both of which influence glucose's generation in hydrolysis of cellulose.

  10. Effect of cellulose whisker content on the properties of poly(ethylene-co-vinyl acetate)/cellulose composites.

    Science.gov (United States)

    Elanthikkal, Silviya; Gopalakrishnapanicker, Unnikrishnan; Varghese, Soney; Guthrie, James T; Francis, Tania

    2013-06-20

    The reinforcing effect of cellulose whiskers, produced from banana waste fibres, has been investigated using poly(ethylene-co-vinyl acetate) [EVA]/cellulose whisker composites. Cellulose whiskers, approximately 300 nm long and 30 nm wide, were obtained via a sulphuric acid hydrolysis method. The effects of the cellulose whisker loading on the thermal properties, mechanical properties and on the morphological features of the composites have been investigated. EVA copolymer with a vinyl acetate segment content of 40% has been used for composite fabrication. The developed composites showed superior thermal and mechanical properties relative to that of the EVA copolymer alone. Three theoretical models, namely the Halpin-Tsai model, the Kerner model and the Nicolais-Narkis model have been employed to provide a basis for the comparison of the results with the observations from the tensile investigations.

  11. Deconvolution Method for Determination of the Nitrogen Content in Cellulose Carbamates

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Cellulose carbamates (CC) were synthesized with microcrystalline cellulose as raw materials. The Fourier transform infrared spectra of CC with different nitrogen content were recorded. The accurate results of the nitrogen content for CC can be obtained by using the deconvolution method when the nitrogen content is less than 3.5%. The relationship between the nitrogen content and the absorption intensity ratio of the corresponding separated absorption peaks in FTIR spectra has been expressed by an equation precisely.

  12. On the determination of crystallinity and cellulose content in plant fibres

    DEFF Research Database (Denmark)

    Thygesen, Anders; Oddershede, Jette; Lilholt, Hans

    2005-01-01

    A comparative study of cellulose crystallinity based on the sample crystallinity and the cellulose content in plant fibres was performed for samples of different origin. Strong acid hydrolysis was found superior to agricultural fibre analysis and comprehensive plant fibre analysis for a consistent...... determination of the cellulose content. Crystallinity determinations were based on X-ray powder diffraction methods using side-loaded samples in reflection (Bragg-Brentano) mode. Rietveld refinements based on the recently published crystal structure of cellulose I beta followed by integration of the crystalline...... and amorphous (background) parts were performed. This was shown to be straightforward to use and in many ways advantageous to traditional crystallinity determinations using the Segal or the Ruland-Vonk methods. The determined cellulose crystallinities were 90 - 100 g/ 100 g cellulose in plant-based fibres...

  13. Lightweight, highly compressible, noncrystalline cellulose capsules.

    Science.gov (United States)

    Carrick, Christopher; Lindström, Stefan B; Larsson, Per Tomas; Wågberg, Lars

    2014-07-08

    We demonstrate how to prepare extraordinarily deformable, gas-filled, spherical capsules from nonmodified cellulose. These capsules have a low nominal density, ranging from 7.6 to 14.2 kg/m(3), and can be deformed elastically to 70% deformation at 50% relative humidity. No compressive strain-at-break could be detected for these dry cellulose capsules, since they did not rupture even when compressed into a disk with pockets of highly compressed air. A quantitative constitutive model for the large deformation compression of these capsules is derived, including their high-frequency mechanical response and their low-frequency force relaxation, where the latter is governed by the gas barrier properties of the dry capsule. Mechanical testing corroborated these models with good accuracy. Force relaxation measurements at a constant compression rendered an estimate for the gas permeability of air through the capsule wall, calculated to 0.4 mL μm/m(2) days kPa at 50% relative humidity. These properties taken together open up a large application area for the capsules, and they could most likely be used for applications in compressible, lightweight materials and also constitute excellent model materials for adsorption and adhesion studies.

  14. Highly ordered cellulose II crystalline regenerated from cellulose hydrolyzed by 1-butyl-3-methylimidazolium chloride.

    Science.gov (United States)

    Ahn, Yongjun; Song, Younghan; Kwak, Seung-Yeop; Kim, Hyungsup

    2016-02-10

    This research focused on the preparation of highly ordered cellulose II crystalline by cellulose hydrolysis in ionic liquid, and the influence of molecular mobility on recrystallization of cellulose. The molar mass of cellulose was controlled by hydrolysis using 1-butyl-3-methylimidazolium chloride (BmimCl). The molecular mobility of cellulose dissolved in BmimCl was characterized by rheological properties. After characterization of cellulose solution and regeneration, change of molar mass and conversion to crystalline were monitored using gel-permeation chromatography and powder X-ray diffraction, respectively. The molar mass of the cellulose in BmimCl was remarkably decreased with an increase in duration time, resulting in better mobility and a lower conformational constraint below critical molar mass. The decrease in molar mass surprisingly increased the crystallinity up to ∼ 85%, suggesting a recrystallization rate dependence of the mobility. The correlation between the mobility and recrystallization rate represented quit different behavior above and below a critical molar mass, which strongly demonstrated to the effect of mobility on the conversion of amorphous state to crystalline structure.

  15. Powerful regulatory systems and post-transcriptional gene silencing resist increases in cellulose content in cell walls of barley

    OpenAIRE

    Tan, Hwei-Ting; Shirley, Neil J; Singh, Rohan R; Henderson, Marilyn; Dhugga, Kanwarpal S; Mayo, Gwenda M; Fincher, Geoffrey B.; Burton, Rachel A.

    2015-01-01

    Background The ability to increase cellulose content and improve the stem strength of cereals could have beneficial applications in stem lodging and producing crops with higher cellulose content for biofuel feedstocks. Here, such potential is explored in the commercially important crop barley through the manipulation of cellulose synthase genes (CesA). Results Barley plants transformed with primary cell wall (PCW) and secondary cell wall (SCW) barley cellulose synthase (HvCesA) cDNAs driven b...

  16. Analysis of cellulose content in stalks and leaves of large leaf tobacco

    Directory of Open Access Journals (Sweden)

    Kulić Gordana J.

    2011-01-01

    Full Text Available Tobacco stalks are an under-utilized material that remains after the harvest of leaves. Given the share of large leaf tobacco in total production in Serbia (more than 85% stalks could be easily available as well as payable raw material in the fabrication of cellulose. The aim of this study was to determine cellulose content in leaves and more importantly in stalks of large leaf tobacco and to provide necessary data to processors engaged in processing of biomass. Stalks and leaves of two types of tobacco, Burley and Virginia, reared in Srem, were used as experimental material samples. Two parallel methods were applied for determining cellulose content: method by Kürschner-Hanack and method by Updegraff. It can be concluded that both methods are applicable to tobacco, but the method by Kürschner-Hanack was found to be simpler, more convenient, faster and economically more cost-effective. Thus, it should be recommended for use. Results showed that stalks of large leaf tobacco contain on average 30.50% to 34.30% of cellulose. There was no statistically significant difference in the cellulose content between the two applied methods. Given the number of plants that lag behind in fields after harvesting leaves, 28,000 tons of cellulose could be used.

  17. The dual effects of lignin content on enzymatic hydrolysis using film composed of cellulose and lignin as a structure model.

    Science.gov (United States)

    Zhang, Lu; Zhang, Liming; Zhou, Tian; Wu, Yuying; Xu, Feng

    2016-01-01

    The degree of delignification during pretreatment is a critical question for economic conversion of biomass to sugar platform. Many models have been used to study the optimum lignin content in biomass, but few of them are able to study without disturbances, such as the complex component and structure of biomass. A novel film model composed of only cellulose and lignin was used to investigate the effect of lignin on enzymatic hydrolysis. High lignin-cellulose proportion (10.00-31.25%) hindered enzymatic hydrolysis, whereas low lignin-cellulose proportion (2.00-8.00%) showed a notable potential to promote enzymatic hydrolysis. The enzymatic hydrolysis rate of lignin-cellulose (6.00%) film was 11.5% higher than that of pure cellulose films. Further study indicated that the promotion was due to the enhancement of film porosity and roughness by residual lignin. Thus, based on the biomimetic model, excessive delignification is not recommended in view of efficient conversion and economy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Effect of silver contents in cellulose nanocrystal/silver nanohybrids on PHBV crystallization and property improvements.

    Science.gov (United States)

    Zhang, Heng; Yu, Hou-Yong; Wang, Chuang; Yao, Juming

    2017-10-01

    Ternary nanocomposites including cellulose nanocrystals/silver nanohybrids (CNC-Ag) and biodegradable poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) were prepared by using solution casting. The effect of different AgNPs contents in the nanohybrids on crystallization ability and properties of PHBV was comprehensively investigated. Compared to binary PHBV/CNC nanocomposite, the ternary nanocomposites with high AgNPs contents showed larger improvements in the thermal stability, mechanical, barrier, overall migration and antibacterial properties. The property transitions at various AgNPs contents were due to transition of the nanohybrids induced PHBV crystallization ability (from single CNC nucleation to synergistic nucleation of CNC and AgNPs), and increased crystallinity without compromising the amounts of hydrogen bonds. Especially, the PHBV/CNC-Ag-1.7 showed the good barrier property and lower migration levels in food simulants, high antibacterial ratio of 99.9% and biocompatibility to human MG-63 cells, suggesting its potential application in food packaging related materials. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Highly efficient organosolv fractionation of cornstalk into cellulose and lignin in organic acids.

    Science.gov (United States)

    Shui, Tao; Feng, Shanghuan; Yuan, Zhongshun; Kuboki, Takashi; Xu, Chunbao Charles

    2016-10-01

    In this study, effects of fractionation solvents, catalysts, temperatures and residence time on yields, purity and chemical composition of the products were investigated at the solid/solvent ratio of 1:5 (g/g). It was revealed that mixture of acetic acid/formic acid/water at the ratio of 3:6:1 (v/v/v) resulted in crude cellulose and lignin products of relatively high purity. The use of HCl catalyst contributed to a high crude cellulose yield, while H2SO4 showed an adverse effect on cellulose yield. However, both of these acidic catalysts contributed to much lower hemicellulose contents in the resulted crude cellulose products compared with those obtained without a catalyst. Fractionation at 90°C for 180min in mixed solvents of acetic acid/formic acid/water (3:6:1, v/v/v) with or without catalyst produced crude cellulose with very low residual lignin contents (<4%). Copyright © 2016. Published by Elsevier Ltd.

  20. High Yield Preparation Method of Thermally Stable Cellulose Nanofibers

    Directory of Open Access Journals (Sweden)

    Hongli Zhu

    2014-02-01

    Full Text Available The preparation of nanocellulose fibers (NFs is achieved through pretreating cellulose in a NaOH/urea/thiourea solution, and then defibrillating the fibers through ultrasonication, resulting in a high yield of 85.4%. Extensive work has been done to optimize the preparation parameters. The obtained NFs are about 30 nm in diameter with cellulose II crystal structure. They possess high thermal stability with an onset of thermal degradation at 270 °C and a maximum degradation temperature of 370 °C. Such NFs have potential applications in transistors and batteries with high thermal stability. NFs-H were obtained by homogenizing undefibrillated fibers separated from the preparation of NFs. NFs-H were also in cellulose II crystal form but with lower thermal stability due to low crystallinity. They can be applied to make highly transparent paper.

  1. Measurements of water content in hydroxypropyl-methyl-cellulose based hydrogels via texture analysis.

    Science.gov (United States)

    Lamberti, Gaetano; Cascone, Sara; Cafaro, Maria Margherita; Titomanlio, Giuseppe; d'Amore, Matteo; Barba, Anna Angela

    2013-01-30

    In this work, a fast and accurate method to evaluate the water content in a cellulose derivative-based matrix subjected to controlled hydration was proposed and tuned. The method is based on the evaluation of the work of penetration required in the needle compression test. The work of penetration was successfully related to the hydrogel water content, assayed by a gravimetric technique. Moreover, a fitting model was proposed to correlate the two variables (the water content and the work of penetration). The availability of a reliable tool is useful both in the quantification of the water uptake phenomena, both in the management of the testing processes of novel pharmaceutical solid dosage forms.

  2. Highly transparent, low-haze, hybrid cellulose nanopaper as electrodes for flexible electronics.

    Science.gov (United States)

    Xu, Xuezhu; Zhou, Jian; Jiang, Long; Lubineau, Gilles; Ng, Tienkhee; Ooi, Boon S; Liao, Hsien-Yu; Shen, Chao; Chen, Long; Zhu, J Y

    2016-06-16

    Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are still characterized by high diffuse transmittance and small direct transmittance, resulting in high optical haze of the substrates. In this study, we proposed a simple methodology for large-scale production of high-transparency, low-haze CNP comprising both long cellulose nanofibrils (CNFs) and short cellulose nanocrystals (CNCs). By varying the CNC/CNF ratio in the hybrid CNP, we could tailor its total transmittance, direct transmittance and diffuse transmittance. By increasing the CNC content, the optical haze of the hybrid CNP could be decreased and its transparency could be increased. The direct transmittance and optical haze of the CNP were 75.1% and 10.0%, respectively, greatly improved from the values of previously reported CNP (31.1% and 62.0%, respectively). Transparent, flexible electrodes were fabricated by coating the hybrid CNP with silver nanowires (AgNWs). The electrodes showed a low sheet resistance (minimum 1.2 Ω sq(-1)) and a high total transmittance (maximum of 82.5%). The electrodes were used to make a light emitting diode (LED) assembly to demonstrate their potential use in flexible displays.

  3. A kinetic study on pyrolysis and combustion characteristics of oil cakes:Effect of cellulose and lignin content

    Institute of Scientific and Technical Information of China (English)

    Ramakrishna Gottipati; Susmita Mishra

    2011-01-01

    Pyrolysis and combustion characteristics of three different oil cakes such as Pongamia ( Pongamia Pinnata), Madhuca (Madhuca Indica), and Jatropha (Jatropha curcas) were investigated in this study.The cellulose and lignin contents of oil cakes play very important role in pyrolysis and combustion processes.A kinetic investigation of three oil cakes was carried out and major part of the samples decomposed between 210 ℃ and 500 ℃.Pyrolysis and combustion were carried out with the mixtures of cellulose and lignin chemicals in different ratios and compared with the oil cakes.The biomass with higher cellulose content showed faster rate of pyrolysis than the biomass with higher lignin content.However at higher temperatures ( >600 ℃ ) all the oil cakes exhibited similar conversion at low heating rate in N2 atmosphere.Apparent activation energies increased for Madhuca and Pongamia oil cakes indicating the presence of more cellulose whereas, low activation energy of Jatropha confirms more lignin content.

  4. Influence of Glycerol Content on Properties of Wheat Gluten/Hydroxyethyl Cellulose Biocomposites

    Institute of Scientific and Technical Information of China (English)

    SONG Yi-hu; ZHENG Qiang; LIU Cheng

    2008-01-01

    Environmentally friendly biocomposites were prepared by blending wheat gluten(WG) as a matrix,hydroxyethyl cellulose(HEC) as a filler,and glycerol as a plasticizer,followed by thermo-molding of the mixture at 120 ℃ for crosslinking the matrix.Moisture absorption,tensile properties,dynamic mechanical analysis,and dynamic theology were evaluated in relation to the glycerol content.Tensile strength and modulus drop dramatically with increasing glycerol content,which is accompanied by significant depression in the glass transition temperature and improvement in the extensibility of the biocomposites.

  5. Highly transparent films from carboxymethylated microfibrillated cellulose: The effect of multiple homogenization steps on key properties

    DEFF Research Database (Denmark)

    Siró, Istvan; Plackett, David; Hedenqvist, M.

    2011-01-01

    We produced microfibrillated cellulose by passing carboxymethylated sulfite-softwood-dissolving pulp with a relatively low hemicellulose content (4.5%) through a high-shear homogenizer. The resulting gel was subjected to as many as three additional homogenization steps and then used to prepare so...... of homogenization, whereas the mean tensile strength, modulus of elasticity, and strain at break were increased by two or three extra homogenization steps. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011...

  6. Deflocculation of Cellulosic Suspensions with Anionic High Molecular Weight Polyelectrolytes

    Directory of Open Access Journals (Sweden)

    Markus Heikki Juhani Korhonen

    2014-04-01

    Full Text Available Pulp fibers have a strong tendency to form flocs in water suspensions, which may cause their undesirable distribution in the paper sheets. This flocculation can be controlled by adding, e.g., an anionic high molecular weight polyelectrolyte in the fiber suspension. The objective of this study was to investigate the effect of anionic polyelectrolytes on deflocculation kinetics, dewatering, and rheology of cellulosic suspensions. The results showed that both microfibrillated cellulose (MFC and macroscopic pulp fibers can be dispersed using anionic polyacrylamides (APAM. The higher the molecular weight of APAM, the higher is its effect. Adsorption experiments illustrate that anionic polyelectrolytes do not strongly attach to cellulose surfaces but they can be partly entrapped or can disperse nanocellulose fibrils (increase the swelling. Based on rheological experiments, the MFC network became weaker with APAM addition. Similar to the flocculation mechanism of cellulosic materials with polymers, deflocculation is also time dependent. Deflocculation occurs very rapidly, and the maximum deflocculation level is achieved within a few seconds. When mixing is continued, the floc size starts to increase again. Also dewatering was found to be strongly dependent on the contact time with the APAMs. These results indicate that the positive effects of anionic deflocculants are quickly diminished due to shear forces, and therefore, the best deflocculating effect is achieved using as short a contact time as possible.

  7. Preparing cationic cotton linter cellulose with high substitution degree by ultrasonic treatment.

    Science.gov (United States)

    Zhang, Fulong; Pang, Zhiqiang; Dong, Cuihua; Liu, Zong

    2015-11-05

    As an important cellulose derivative, cationic cellulose has becoming an attractive material. However, it remains challenging to produce cationic cellulose with high substitute degree. In this paper, we successfully increased the substitute degree of cationic cellulose by introducing ultrasonic treatment, which efficiently breaks hydrogen bonds of the chemical structure of cationic cellulose. Properties of cationic cellulose were studied by scanning electron spectroscope (SEM), contact angle, X-ray diffraction (XRD) and thermogravimetric analysis (TGA). Experimental results show that the cationic cellulose has rougher surface and lower crystallinity degree as compared to the original sample. TGA analysis verifies that the thermostability of CLC decreases after the cationic modification. The residual of the cationic cellulose (25 wt%) after pyrolysis increases significantly as compared to that of the original cellulose (15 wt%).

  8. Cellulose with a High Fractal Dimension Is Easily Hydrolysable under Acid Catalysis

    Directory of Open Access Journals (Sweden)

    Mariana Díaz

    2017-05-01

    Full Text Available The adsorption of three diverse amino acids couples onto the surface of microcrystalline cellulose was studied. Characterisation of modified celluloses included changes in the polarity and in roughness. The amino acids partially break down the hydrogen bonding network of the cellulose structure, leading to more reactive cellulose residues that were easily hydrolysed to glucose in the presence of hydrochloric acid or tungstophosphoric acid catalysts. The conversion of cellulose and selectivity for glucose was highly dependent on the self-assembled amino acids adsorbed onto the cellulose and the catalyst.

  9. Cellulose kraft pulp reinforced polylactic acid (PLA composites: effect of fibre moisture content

    Directory of Open Access Journals (Sweden)

    Elias Retulainen

    2016-06-01

    Full Text Available PLA offers a competitive and CO2 neutral matrix to commonly used polyolefin polymer based composites. Moreover, the use of PLA reduces dependency on oil when producing composite materials. However, PLA has a tendency of hydrolytic degradation under melt processing conditions in the presence of moisture, which remains a challenge when processing PLA reinforced natural fibre composites. Natural fibres such as cellulose fibres are hygroscopic with 6–10 wt% moisture content at 50–70% relative humidity conditions. These fibres are sensitive to melt processing conditions and fibre breakage (cutting also occur during processing. The degradation of PLA, moisture absorption of natural fibres together with fibre cutting and uneven dispersion of fibres in polymer matrix, deteriorates the overall properties of the composite. In the given research paper, bleached softwood kraft pulp (BSKP reinforced PLA compounds were successfully melt processed using BSKP with relatively high moisture contents. The effect of moist BSKP on the molecular weight of PLA, fibre length and the mechanical properties of the composites were investigated. By using moist never-dried kraft pulp fibres for feeding, the fibre cutting was decreased during the melt compounding. Even though PLA degradation occurred during the melt processing, the final damage to the PLA was moderate and thus did not deteriorate the mechanical properties of the composites. However, comprehensive moisture removal is required during the compounding in order to achieve optimal overall performance of the PLA/BSKP composites. The economic benefit gained from using moist BSKP is that the expensive and time consuming drying process steps of the kraft pulp fibres prior to processing can be minimized.

  10. Cellulose synthase complexes act in a concerted fashion to synthesize highly aggregated cellulose in secondary cell walls of plants.

    Science.gov (United States)

    Li, Shundai; Bashline, Logan; Zheng, Yunzhen; Xin, Xiaoran; Huang, Shixin; Kong, Zhaosheng; Kim, Seong H; Cosgrove, Daniel J; Gu, Ying

    2016-10-04

    Cellulose, often touted as the most abundant biopolymer on Earth, is a critical component of the plant cell wall and is synthesized by plasma membrane-spanning cellulose synthase (CESA) enzymes, which in plants are organized into rosette-like CESA complexes (CSCs). Plants construct two types of cell walls, primary cell walls (PCWs) and secondary cell walls (SCWs), which differ in composition, structure, and purpose. Cellulose in PCWs and SCWs is chemically identical but has different physical characteristics. During PCW synthesis, multiple dispersed CSCs move along a shared linear track in opposing directions while synthesizing cellulose microfibrils with low aggregation. In contrast, during SCW synthesis, we observed swaths of densely arranged CSCs that moved in the same direction along tracks while synthesizing cellulose microfibrils that became highly aggregated. Our data support a model in which distinct spatiotemporal features of active CSCs during PCW and SCW synthesis contribute to the formation of cellulose with distinct structure and organization in PCWs and SCWs of Arabidopsis thaliana This study provides a foundation for understanding differences in the formation, structure, and organization of cellulose in PCWs and SCWs.

  11. Equilibrium Water Contents of Cellulose Films Determined via Solvent Exchange and Quartz Crystal Microbalance with Dissipation Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Kittle, Joshua D; Du, Xiaosong; Jiang, Feng; Qian, Chen; Heinze, Thomas; Roman, Maren; Esker, Alan R

    2011-08-08

    Model cellulose surfaces have attracted increasing attention for studying interactions with cell wall matrix polymers and as substrates for enzymatic degradation studies. Quartz crystal microbalance with dissipation monitoring (QCM-D) solvent exchange studies showed that the water content of regenerated cellulose (RC) films was proportional to the film thickness (d) and was consistent with about five water molecules per anhydroglucose unit. Sulfated nanocrystalline cellulose (SNC) and desulfated nanocrystalline cellulose (DNC) films had comparable water contents and contained about five times more water than RC films. A cellulase mixture served as a probe for studies of substrate accessibility and degradation. Cellulase adsorption onto RC films was independent of d, whereas degradation times increased with d. However, adsorption onto SNC and DNC films increased with d, whereas cellulase degradation times for DNC films were independent of studied d. Enhanced access to guest molecules for SNC and DNC films revealed they are more porous than RC films.

  12. Equilibrium water contents of cellulose films determined via solvent exchange and quartz crystal microbalance with dissipation monitoring.

    Science.gov (United States)

    Kittle, Joshua D; Du, Xiaosong; Jiang, Feng; Qian, Chen; Heinze, Thomas; Roman, Maren; Esker, Alan R

    2011-08-08

    Model cellulose surfaces have attracted increasing attention for studying interactions with cell wall matrix polymers and as substrates for enzymatic degradation studies. Quartz crystal microbalance with dissipation monitoring (QCM-D) solvent exchange studies showed that the water content of regenerated cellulose (RC) films was proportional to the film thickness (d) and was consistent with about five water molecules per anhydroglucose unit. Sulfated nanocrystalline cellulose (SNC) and desulfated nanocrystalline cellulose (DNC) films had comparable water contents and contained about five times more water than RC films. A cellulase mixture served as a probe for studies of substrate accessibility and degradation. Cellulase adsorption onto RC films was independent of d, whereas degradation times increased with d. However, adsorption onto SNC and DNC films increased with d, whereas cellulase degradation times for DNC films were independent of studied d. Enhanced access to guest molecules for SNC and DNC films revealed they are more porous than RC films.

  13. Cellulose antibody films for highly specific evanescent wave immunosensors

    Science.gov (United States)

    Hartmann, Andreas; Bock, Daniel; Jaworek, Thomas; Kaul, Sepp; Schulze, Matthais; Tebbe, H.; Wegner, Gerhard; Seeger, Stefan

    1996-01-01

    For the production of recognition elements for evanescent wave immunosensors optical waveguides have to be coated with ultrathin stable antibody films. In the present work non amphiphilic alkylated cellulose and copolyglutamate films are tested as monolayer matrices for the antibody immobilization using the Langmuir-Blodgett technique. These films are transferred onto optical waveguides and serve as excellent matrices for the immobilization of antibodies in high density and specificity. In addition to the multi-step immobilization of immunoglobulin G(IgG) on photochemically crosslinked and oxidized polymer films, the direct one-step transfer of mixed antibody-polymer films is performed. Both planar waveguides and optical fibers are suitable substrates for the immobilization. The activity and specificity of immobilized antibodies is controlled by the enzyme-linked immunosorbent assay (ELISA) technique. As a result reduced non-specific interactions between antigens and the substrate surface are observed if cinnamoylbutyether-cellulose is used as the film matrix for the antibody immobilization. Using the evanescent wave senor (EWS) technology immunosensor assays are performed in order to determine both the non-specific adsorption of different coated polymethylmethacrylat (PMMA) fibers and the long-term stability of the antibody films. Specificities of one-step transferred IgG-cellulose films are drastically enhanced compared to IgG-copolyglutamate films. Cellulose IgG films are used in enzymatic sandwich assays using mucine as a clinical relevant antigen that is recognized by the antibodies BM2 and BM7. A mucine calibration measurement is recorded. So far the observed detection limit for mucine is about 8 ng/ml.

  14. Highly transparent, low-haze, hybrid cellulose nanopaper as electrodes for flexible electronics

    Science.gov (United States)

    Xu, Xuezhu; Zhou, Jian; Jiang, Long; Lubineau, Gilles; Ng, Tienkhee; Ooi, Boon S.; Liao, Hsien-Yu; Shen, Chao; Chen, Long; Zhu, J. Y.

    2016-06-01

    Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are still characterized by high diffuse transmittance and small direct transmittance, resulting in high optical haze of the substrates. In this study, we proposed a simple methodology for large-scale production of high-transparency, low-haze CNP comprising both long cellulose nanofibrils (CNFs) and short cellulose nanocrystals (CNCs). By varying the CNC/CNF ratio in the hybrid CNP, we could tailor its total transmittance, direct transmittance and diffuse transmittance. By increasing the CNC content, the optical haze of the hybrid CNP could be decreased and its transparency could be increased. The direct transmittance and optical haze of the CNP were 75.1% and 10.0%, respectively, greatly improved from the values of previously reported CNP (31.1% and 62.0%, respectively). Transparent, flexible electrodes were fabricated by coating the hybrid CNP with silver nanowires (AgNWs). The electrodes showed a low sheet resistance (minimum 1.2 Ω sq-1) and a high total transmittance (maximum of 82.5%). The electrodes were used to make a light emitting diode (LED) assembly to demonstrate their potential use in flexible displays.Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are

  15. Co-downregulation of the hydroxycinnamoyl-CoA:shikimate hydroxycinnamoyl transferase and coumarate 3-hydroxylase significantly increases cellulose content in transgenic alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Tong, Zongyong; Li, Heng; Zhang, Rongxue; Ma, Lei; Dong, Jiangli; Wang, Tao

    2015-10-01

    Lignin is a component of the cell wall that is essential for growth, development, structure and pathogen resistance in plants, but high lignin is an obstacle to the conversion of cellulose to ethanol for biofuel. Genetically modifying lignin and cellulose contents can be a good approach to overcoming that obstacle. Alfalfa (Medicago sativa L.) is rich in lignocellulose biomass and used as a model plant for the genetic modification of lignin in this study. Two key enzymes in the lignin biosynthesis pathway-hydroxycinnamoyl -CoA:shikimate hydroxycinnamoyl transferase (HCT) and coumarate 3-hydroxylase (C3H)-were co-downregulated. Compared to wild-type plants, the lignin content in the modified strain was reduced by 38%, cellulose was increased by 86.1%, enzyme saccharification efficiency was increased by 10.9%, and cell wall digestibility was increased by 13.0%. The modified alfalfa exhibited a dwarf phenotype, but normal above ground biomass. This approach provides a new strategy for reducing lignin and increasing cellulose contents and creates a new genetically modified crop with enhanced value for biofuel. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. Overexpression of UDP-glucose pyrophosphorylase gene could increase cellulose content in Jute (Corchorus capsularis L.).

    Science.gov (United States)

    Zhang, Gaoyang; Qi, Jianmin; Xu, Jiantang; Niu, Xiaoping; Zhang, Yujia; Tao, Aifen; Zhang, Liwu; Fang, Pingping; Lin, Lihui

    2013-12-13

    In this study, the full-length cDNA of the UDP-glucose pyrophosphorylase gene was isolated from jute by homologous cloning (primers were designed according to the sequence of UGPase gene of other plants) and modified RACE techniques; the cloned gene was designated CcUGPase. Using bioinformatic analysis, the gene was identified as a member of the UGPase gene family. Real-time PCR analysis revealed differential spatial and temporal expression of the CcUGPase gene, with the highest expression levels at 40 and 120d. PCR and Southern hybridization results indicate that the gene was integrated into the jute genome. Overexpression of CcUGPase gene in jute revealed increased height and cellulose content compared with control lines, although the lignin content remained unchanged. The results indicate that the jute UGPase gene participates in cellulose biosynthesis. These data provide an important basis for the application of the CcUGPase gene in the improvement of jute fiber quality. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Highly transparent, low-haze, hybrid cellulose nanopaper as electrodes for flexible electronics

    KAUST Repository

    Xu, Xuezhu

    2016-06-01

    Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are still characterized by high diffuse transmittance and small direct transmittance, resulting in high optical haze of the substrates. In this study, we proposed a simple methodology for large-scale production of high-transparency, low-haze CNP comprising both long cellulose nanofibrils (CNFs) and short cellulose nanocrystals (CNCs). By varying the CNC/CNF ratio in the hybrid CNP, we could tailor its total transmittance, direct transmittance and diffuse transmittance. By increasing the CNC content, the optical haze of the hybrid CNP could be decreased and its transparency could be increased. The direct transmittance and optical haze of the CNP were 75.1% and 10.0%, respectively, greatly improved from the values of previously reported CNP (31.1% and 62.0%, respectively). Transparent, flexible electrodes were fabricated by coating the hybrid CNP with silver nanowires (AgNWs). The electrodes showed a low sheet resistance (minimum 1.2 Ω sq-1) and a high total transmittance (maximum of 82.5%). The electrodes were used to make a light emitting diode (LED) assembly to demonstrate their potential use in flexible displays. © 2016 The Royal Society of Chemistry.

  18. Synthesis and properties of regenerated cellulose-based hydrogels with high strength and transparency for potential use as an ocular bandage

    Energy Technology Data Exchange (ETDEWEB)

    Patchan, M. [Research and Exploratory Development Department, The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States); Graham, J.L. [Department of Biomedical Engineering, Johns Hopkins University, School of Medicine, 720 Rutland Avenue/Ross 720, Baltimore, MD 21205 (United States); Xia, Z.; Maranchi, J.P. [Research and Exploratory Development Department, The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States); McCally, R. [Research and Exploratory Development Department, The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States); Wilmer Eye Institute, Johns Hopkins Medical Institutions, 600 N. Wolfe Street, Baltimore, MD 21287 (United States); Schein, O. [Wilmer Eye Institute, Johns Hopkins Medical Institutions, 600 N. Wolfe Street, Baltimore, MD 21287 (United States); Elisseeff, J.H. [Department of Biomedical Engineering, Johns Hopkins University, School of Medicine, 720 Rutland Avenue/Ross 720, Baltimore, MD 21205 (United States); Trexler, M.M., E-mail: morgana.trexler@jhuapl.edu [Research and Exploratory Development Department, The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States)

    2013-07-01

    Cellulose is a biologically derived material with excellent wound-healing properties. The high strength of cellulose fibers and the ability to synthesize gels with high optical transparency make these materials suitable for ocular applications. In this study, cellulose materials derived from wood pulp, cotton, and bacterial sources were dissolved in lithium chloride/N,N-dimethylacetamide to form regenerated cellulose hydrogels. Material properties of the resulting hydrogels, including water content, optical transparency, and tensile and tear strengths, were evaluated. Synthesis parameters, including activation time, dissolution time, relative humidity, and cellulose concentration, were found to impact the material properties of the resulting hydrogels. Overnight activation time improves the optical transparency of the hydrogels from 77% to 97% at 550 nm, whereas controlling cellulose concentration improves their tear strength by as much as 200%. On the basis of the measured transmittance and strength values of the regenerated hydrogels prepared via the optimized synthesis parameters, Avicel PH 101, Sigma-Aldrich microcrystalline cellulose 435236, and bacterial cellulose types were prioritized for future biocompatibility testing and potential clinical investigation. - Highlights: • Hydrogels were prepared (via LiCl/DMAc) from 7 different types of cellulose. • Synthesis parameters (activation, gelation, and concentration) were optimized. • Impact of synthesis parameters on transparency and strength was explored.

  19. Extensional Flow Properties of Externally Plasticized Cellulose Acetate: Influence of Plasticizer Content

    Directory of Open Access Journals (Sweden)

    Hans-Joachim Radusch

    2013-07-01

    Full Text Available Elongational flow properties of polymer melts are very important for numerous polymer processing technologies such as blown film extrusion or foam extrusion. Rheotens tests were conducted to investigate the influence of plasticizer content on elongational flow properties of cellulose acetate (CA. Triethyl citrate (TEC was used as plasticizer. Melt strength decreases whereas melt extensibility increases with increasing plasticizer content. Melt strength was further studied as a function of zero shear viscosity. The typical draw resonance of the Rheotens curve shifts to higher drawdown velocity and the amplitude of the draw resonance decreases with increasing TEC content. With respect to foam extrusion, not only are melt strength and melt extensibility important but the elongational behavior at low strain rates and the area under the Rheotens curve are also significant. Therefore, elongational viscosity as well as specific energy input were calculated and investigated with respect to plasticizer content. Preliminary foam extrusion tests of externally plasticized CA using chemical blowing agents confirm the results from rheological characterization.

  20. Effect of sample moisture content on XRD-estimated cellulose crystallinity index and crystallite size

    Science.gov (United States)

    Umesh P. Agarwal; Sally A. Ralph; Carlos Baez; Richard S. Reiner; Steve P. Verrill

    2017-01-01

    Although X-ray diffraction (XRD) has been the most widely used technique to investigate crystallinity index (CrI) and crystallite size (L200) of cellulose materials, there are not many studies that have taken into account the role of sample moisture on these measurements. The present investigation focuses on a variety of celluloses and cellulose...

  1. Nanofibrillated Cellulose (NFC: A High-Value Co-Product that Improves the Economics of Cellulosic Ethanol Production

    Directory of Open Access Journals (Sweden)

    Qiong Song

    2014-02-01

    Full Text Available Cellulosic ethanol is a sustainable alternative to petroleum as a transportation fuel, which could be made biologically from agricultural and forestry residues, municipal waste, or herbaceous and woody crops. Instead of putting efforts on steps overcoming the natural resistance of plants to biological breakdown, our study proposes a unique pathway to improve the outcome of the process by co-producing high-value nanofibrillated cellulose (NFC, offering a new economic leverage for cellulosic ethanol to compete with fossil fuels in the near future. In this study, glucose has been produced by commercial enzymes while the residual solids are converted into NFC via sonification. Here, we report the morphology of fibers changed through the process and yield of glucose in the enzymatic hydrolysis step.

  2. Genome sequence and plasmid transformation of the model high-yield bacterial cellulose producer Gluconacetobacter hansenii ATCC 53582

    Science.gov (United States)

    Florea, Michael; Reeve, Benjamin; Abbott, James; Freemont, Paul S.; Ellis, Tom

    2016-03-01

    Bacterial cellulose is a strong, highly pure form of cellulose that is used in a range of applications in industry, consumer goods and medicine. Gluconacetobacter hansenii ATCC 53582 is one of the highest reported bacterial cellulose producing strains and has been used as a model organism in numerous studies of bacterial cellulose production and studies aiming to increased cellulose productivity. Here we present a high-quality draft genome sequence for G. hansenii ATCC 53582 and find that in addition to the previously described cellulose synthase operon, ATCC 53582 contains two additional cellulose synthase operons and several previously undescribed genes associated with cellulose production. In parallel, we also develop optimized protocols and identify plasmid backbones suitable for transformation of ATCC 53582, albeit with low efficiencies. Together, these results provide important information for further studies into cellulose synthesis and for future studies aiming to genetically engineer G. hansenii ATCC 53582 for increased cellulose productivity.

  3. Growth, cellulose, and lignin content of ramie (Boehmeria nivea L. Gaudich with treatment of Gibberelic Acid (GA3¬

    Directory of Open Access Journals (Sweden)

    WIDYA MUDYANTINI

    2008-10-01

    Full Text Available The aims of this research were to: (i study the effects of gibberellic acid (GA3 to the growth of Boehmeria nivea L. Gaudich, and (ii study the effects of gibberellic acid (GA3 to the cellulose and lignin content of B. nivea. GA3 could delivered starch hydrolysis that could support α-amylase formation that would increase glucose. Increasing glucose concentration caused the rising of osmotic pressure inside the cell so that the cells expand. The initial synthetic path of cellulose was glucose, as well as lignin. If GA3 could increased the glucose amount in plant, then the cellulose and lignin amount also increased. This experiment use Completely Random Design with one factor, they are concentration gibberellic acid that consist of 6 treatment concentration are GA3 0 ppm, GA3 50 ppm, GA3 100 ppm, GA3 150 ppm, GA3 200 ppm, and GA3 250 ppm. The treatment to the rhizome had been done before it was planted. Some parameters like growth and anatomy parameter are measured. The results showed that treatment GA3 affect to the improvement of bud stem diameter, length of bud stem, the wet weight, dry weight, length of phloem bundle, phloem number, and lignin content but they does not affect to the change of bud number, leaf number, and cellulose content. The treatment of GA3 on GA3 200 ppm show the maximum result to the improvement of bud stem diameter, length of bud stem, the wet weight, dry weight, length of phloem bundle, phloem number, and cellulose content The treatment of GA3 on GA3 250 ppm show maximum result to the improvement of bud number, leaf number, and lignin content.

  4. Endurance of high molecular weight carboxymethyl cellulose in corrosive environments

    Science.gov (United States)

    Murodov, M. M.; Rahmanberdiev, G. R.; Khalikov, M. M.; Egamberdiev, E. A.; Negmatova, K. C.; Saidov, M. M.; Mahmudova, N.

    2012-07-01

    Lignin obtained from the waste cooking liquor, formed after soda pulping process, is used as an inhibitor of NaCMC thermo oxidative degradation in presence of in extreme conditions during drilling oil wells. In this paper the schematic process of obtaining NaCMC by the principle of "monoapparat" on the basis of cellulose produced by non-wood cellulose materials is presented.

  5. Charging process of polyurethane based composites under electronic irradiation: Effects of cellulose fiber content

    Energy Technology Data Exchange (ETDEWEB)

    Hadjadj, Aomar; Jbara, Omar; Tara, Ahmed; Gilliot, Mickael [Laboratoire d' Ingénierie et Sciences des Matériaux (LISM EA 4695), Université de Reims Champagne-Ardenne, 51687 Reims cedex 2 (France); Dellis, Jean-Luc [Laboratoire de Physique de la Matière Condensée (LPMC EA 2081), Université de Picardie Jules Vernes, 80009 Amiens cedex 1 (France)

    2013-09-23

    The study deals with the charging effect of polyurethanes-based composites reinforced with cellulose fibers, under electronic beam irradiation in a scanning electron microscope. The results indicate that the leakage current and the trapped charge as well as the kinetics of charging process significantly change beyond a critical concentration of 10% cellulose fibers. These features are correlated with the cellulose concentration-dependence of the electrical properties, specifically resistivity and capacitance, of the composite.

  6. Charging process of polyurethane based composites under electronic irradiation: Effects of cellulose fiber content

    Science.gov (United States)

    Hadjadj, Aomar; Jbara, Omar; Tara, Ahmed; Gilliot, Mickael; Dellis, Jean-Luc

    2013-09-01

    The study deals with the charging effect of polyurethanes-based composites reinforced with cellulose fibers, under electronic beam irradiation in a scanning electron microscope. The results indicate that the leakage current and the trapped charge as well as the kinetics of charging process significantly change beyond a critical concentration of 10% cellulose fibers. These features are correlated with the cellulose concentration-dependence of the electrical properties, specifically resistivity and capacitance, of the composite.

  7. Production of high concentrated cellulosic ethanol by acetone/water oxidized pretreated beech wood.

    Science.gov (United States)

    Katsimpouras, Constantinos; Kalogiannis, Konstantinos G; Kalogianni, Aggeliki; Lappas, Angelos A; Topakas, Evangelos

    2017-01-01

    Lignocellulosic biomass is an abundant and inexpensive resource for biofuel production. Alongside its biotechnological conversion, pretreatment is essential to enable efficient enzymatic hydrolysis by making cellulose susceptible to cellulases. Wet oxidation of biomass, such as acetone/water oxidation, that employs hot acetone, water, and oxygen, has been found to be an attractive pretreatment method for removing lignin while producing less degradation products. The remaining enriched cellulose fraction has the potential to be utilized under high gravity enzymatic saccharification and fermentation processes for the cost-competing production of bioethanol. Beech wood residual biomass was pretreated following an acetone/water oxidation process aiming at the production of high concentration of cellulosic ethanol. The effect of pressure, reaction time, temperature, and acetone-to-water ratio on the final composition of the pretreated samples was studied for the efficient utilization of the lignocellulosic feedstock. The optimal conditions were acetone/water ratio 1:1, 40 atm initial pressure of 40 vol% O2 gas, and 64 atm at reaction temperature of 175 °C for 2 h incubation. The pretreated beech wood underwent an optimization step studying the effect of enzyme loading and solids content on the enzymatic liquefaction/saccharification prior to fermentation. In a custom designed free-fall mixer at 50 °C for either 6 or 12 h of prehydrolysis using an enzyme loading of 9 mg/g dry matter at 20 wt% initial solids content, high ethanol concentration of 75.9 g/L was obtained. The optimization of the pretreatment process allowed the efficient utilization of beech wood residual biomass for the production of high concentrations of cellulosic ethanol, while obtaining lignin that can be upgraded towards high-added-value chemicals. The threshold of 4 wt% ethanol concentration that is required for the sustainable bioethanol production was surpassed almost twofold

  8. Comparison of holocellulose,. cap alpha. -cellulose and lignin contents of trunk and branch wood of some conifers of Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Mahmood, A.; Mahmood, T.

    1985-01-01

    Samples of trunk and branchwood of 7 conifer species growing under forest conditions in Pakistan were analysed to evaluate the suitability of branchwood for the pulp and paper industries. Holocellulose content in the branchwood of Cedrus deodara, Juniperus polycarpos, Pinus halepensis and Pinus roxburghii-amerciana(.) was comparable with values for their truckwood. The branchwood of Abies prindrow, P. rotberghii and P. wallichiana contained less holocellusose than the trunkwood. The branchwood of A. pindrow, C. deodara, and P. roxburghii-americana contained less ..cap alpha..-cellulose than the trunkwood, but ..cap alpha..-cellulose contents were comparable in the other 4 species. The lignin contents of trunk and branchwood were comparable in A. pindrow, C. deodara and P. roxburghii-americana, but showed some variation in the other species. 5 references.

  9. The effect of different anti-solvent and coconut shell content on properties of coconut shell regenerated cellulose biocomposite films

    Science.gov (United States)

    Hahary, Farah Norain; Husseinsyah, Salmah; Mostapha@Zakaria, Marliza

    2016-07-01

    In this study, coconut shell (CS) regenerated cellulose (RC) biocomposite films was prepared using dimethylacetamide/lithium chloride (DMAc/LiCl) solvent system. The effect of anti-solvents such as water and methanol for regeneration of cellulose and coconut shell content on properties of CS-RC biocomposite films was investigated. The used of water as anti-solvent for cellulose regeneration was found to have higher tensile properties compared to regenerated cellulose using methanol. Besides, the X-Ray diffraction (XRD) analysis also revealed that RC using water as anti-solvent have higher crystallinity index (CrI) than CS-RC biocomposite film using methanol. The tensile strength and modulus elasticity of CS-RC biocomposite films increased up to 3 wt% CS and decreased with further addition of CS. The elongation at break of CS-RC biocomposite films decreased with the increment of CS. The CrI of CS-RC bioocmposite films up to 3 wt% and decreased with at higher content of CS.

  10. PREPARATION AND CHARACTERISTICS OF ANIONIC POLYACRYLAMIDES CONTAINING DIRECT DYE WITH A HIGH AFFINITY FOR CELLULOSE

    Directory of Open Access Journals (Sweden)

    Shingo Yokota

    2009-05-01

    Full Text Available Direct dye with a high affinity for cellulose substrate was utilized as a cellulose anchor to promote retention of paper strengthening additives under various conditions associated with the wet end of a paper machine. Direct Red 28 (DR was covalently linked to anionic polyacrylamide (A-PAM via a condensation reaction using water-soluble carbodiimide. The DR-conjugated A-PAM (DR-A-PAM demonstrated good retention efficiency, resulting in strength enhancement of handsheets. Anionic trash showed no interference with the performance of DR-A-PAM in the wet end, while the additive performance was sensitive to calcium ions. Surface plasmon resonance analysis gave useful information on the cellulose-anchoring ability of DR-A-PAM. Dye molecules were irreversibly adsorbed onto the cellulose substrate under aqueous conditions, while A-PAM possessed no significant affinity for cellulose. These results suggest that anionic DR moieties in DR-A-PAM molecules served as a cellulose-anchor, possibly due to multiple CH-π interaction between hydrophobic face of cellulose substrate and π-conjugated system of dye molecules. Such a unique interaction of direct dye and cellulose provides a new insight into the wet end system, and does not depend on conventional electrostatic attraction.

  11. High pressure HC1 conversion of cellulose to glucose

    Energy Technology Data Exchange (ETDEWEB)

    Antonoplis, Robert Alexander; Blanch, Harvey W.; Wilke, Charles R.

    1981-08-01

    The production of ethanol from glucose by means of fermentation represents a potential long-range alternative to oil for use as a transportation fuel. Today's rising oil prices and the dwindling world supply of oil have made other fuels, such as ethanol, attractive alternatives. It has been shown that automobiles can operate, with minor alterations, on a 10% ethanol-gasoline mixture popularly known as gasohol. Wood has long been known as a potential source of glucose. Glucose may be obtained from wood following acid hydrolysis. In this research, it was found that saturating wood particles with HCl gas under pressure was an effective pretreatment before subjecting the wood to dilute acid hydrolysis. The pretreatment is necessary because of the tight lattice structure of cellulose, which inhibits dilute acid hydrolysis. HCl gas makes the cellulose more susceptible to hydrolysis and the glucose yield is doubled when dilute acid hydrolysis is preceded by HCl saturation at high pressure. The saturation was most effectively performed in a fluidized bed reactor, with pure HCl gas fluidizing equal volumes of ground wood and inert particles. The fluidized bed effectively dissipated the large amount of heat released upon HCl absorption into the wood. Batch reaction times of one hour at 314.7 p.s.i.a. gave glucose yields of 80% and xylose yields of 95% after dilute acid hydrolysis. A non-catalytic gas-solid reaction model, with gas diffusing through the solid limiting the reaction rate, was found to describe the HCl-wood reaction in the fluidized bed. HCl was found to form a stable adduct with the lignin residue in the wood, in a ratio of 3.33 moles per mole of lignin monomer. This resulted in a loss of 0.1453 lb. of HCl per pound of wood. The adduct was broken upon the addition of water. A process design and economic evaluation for a plant to produce 214 tons per day of glucose from air-dried ground Populus tristi gave an estimated glucose cost of 15.14 cents per pound

  12. High performance films of cellulose butyral derivative having a necklace-like annular structure in the side chains

    OpenAIRE

    2014-01-01

    We fabricated high performance films using cellulose butyral (CB) synthesized from native cellulose. Two-step reactions were adopted to produce the derivative CB, including etherification of cellulose with glycidol in NaOH/urea aqueous solution to yield O-(2, 3-dihydroxypropyl) cellulose (DHPC), and butyralization of DHPC. Both DHPC and CB products were easily processed into a thin film by hot-press molding. The butyral modifier significantly improved the tenacity of highly ductile DHPC, by v...

  13. Implications of Industrial Processing Strategy on Cellulosic Ethanol Production at High Solids Concentrations

    DEFF Research Database (Denmark)

    Cannella, David

    are the leftover of agricultural productions (straws), not edible crops (giant reed) or wood, thus the ethanol so produced is also called second generation (or 2G ethanol), which differs from the first generation produced from starch (sugar beets mostly). In the industrial production of cellulosic ethanol high...... cellulosic ethanol processing at high solids conditions. Moreover for the first time in literature the activity of LPMOs on real lignocellulosic substrate and during cellulosic ethanol production is characterized. Hence describing the enzymatic scale dynamics when resembling in planta conditions, i...

  14. Radiation-Induced High-Temperature Conversion of Cellulose

    Directory of Open Access Journals (Sweden)

    Alexander V. Ponomarev

    2014-10-01

    Full Text Available Thermal decomposition of cellulose can be upgraded by means of an electron-beam irradiation to produce valuable organic products via chain mechanisms. The samples being irradiated decompose effectively at temperatures below the threshold of pyrolysis inception. Cellulose decomposition resembles local “explosion” of the glucopyranose unit when fast elimination of carbon dioxide and water precede formation of residual carbonyl or carboxyl compounds. The dry distillation being performed during an irradiation gives a liquid condensate where furfural and its derivatives are dominant components. Excessively fast heating is adverse, as it results in a decrease of the yield of key organic products because pyrolysis predominates over the radiolytic-controlled decomposition of feedstock. Most likely, conversion of cellulose starts via radiolytic formation of macroradicals do not conform with each other, resulting in instability of the macroradical. As a consequence, glucosidic bond cleavage, elimination of light fragments (water, carbon oxides, formaldehyde, etc. and formation of furfural take place.

  15. Highly Effective Electromagnetic Interference Shielding Materials based on Silver Nanowire/Cellulose Papers.

    Science.gov (United States)

    Lee, Tae-Won; Lee, Sang-Eui; Jeong, Young Gyu

    2016-05-25

    We fabricated silver nanowire (AgNW)-coated cellulose papers with a hierarchical structure by an efficient and facile dip-coating process, and investigated their microstructures, electrical conductivity and electromagnetic interference (EMI) shielding effectiveness. SEM images confirm that AgNWs are coated dominantly on the paper surfaces, although they exist partially in the inner parts of the cellulose papers, which demonstrates that the AgNW density gradually decreases in thickness direction of the AgNW/cellulose papers. This result is supported by the anisotropic apparent electrical conductivity of the AgNW/cellulose papers depending on in-plane or thickness direction. Even for a AgNW/cellulose paper obtained by a single dip-coating cycle, the apparent electrical conductivity in the in-plane direction of 0.34 S/cm is achieved, which is far higher than the neat cellulose paper with ∼10(-11) S/cm. In addition, the apparent electrical conductivity of the papers in the in-plane direction increases significantly from 0.34 to 67.51 S/cm with increasing the number of dip-coating cycle. Moreover, although the AgNW/cellulose paper with 67.51 S/cm possesses 0.53 vol % AgNW only, it exhibits high EMI shielding performance of ∼48.6 dB at 1 GHz. This indicates that the cellulose paper structure is highly effective to form a conductive AgNW network. Overall, it can be concluded that the AgNW/cellulose papers with high flexibility and low density can be used as electrically conductive components and EMI shielding elements in advanced application areas.

  16. Effect of high-energy radiation and alkali treatment on the properties of cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Foeldvary, Cs.M. E-mail: foldvary@iki.kfki.hu; Takacs, E.; Wojnarovits, L

    2003-06-01

    The effect of the treatment with NaOH or tetramethyl ammonium hydroxide solutions on preirradiated cotton-cellulose was investigated. Both the radiation and the treatment with alkali solutions caused loss of weight in cellulose; however, there was a synergism, a high weight loss was observed during alkali treatment of preirradiated samples. The radiation caused scissions of the cellulose chains and during the treatment with aqueous alkaline solutions some smaller fragments dissolved, resulting in a strong absorbance of the solutions with maximum at around 268 nm. It was attributed to the absorbance of aldehyde/keto groups.

  17. The influence of the moisture content of microcrystalline cellulose on the coating process in a fluidized bed

    Directory of Open Access Journals (Sweden)

    Silva O. S.

    2004-01-01

    Full Text Available The objective of this work was to study the coating of microcrystalline cellulose with a polymeric suspension in a fluidized bed. The coating operation was carried out using a fluidized bed with top spraying by a double-fluid nozzle. The fluidized bed consists of a cylindrical column made of plexiglass with a height of 0.6 m and an inner diameter of 0.14 m. The polymeric coating suspension was formulated using Eudragit® as the basic component. As the quality of the coating product is greatly affected by the spraying characteristics, the influence of the flow rate of the coating suspension and the moisture content of the particles on the agglomeration index and efficiency of the process of coating microcrystalline cellulose was analyzed.

  18. High Pressure Compression-Molding of α-Cellulose and Effects of Operating Conditions

    Directory of Open Access Journals (Sweden)

    Antoine Rouilly

    2013-05-01

    Full Text Available Commercial α-cellulose was compression-molded to produce 1A dog-bone specimens under various operating conditions without any additive. The resulting agromaterials exhibited a smooth, plastic-like surface, and constituted a suitable target as replacement for plastic materials. Tensile and three-points bending tests were conducted according to ISO standards related to the evaluation of plastic materials. The specimens had strengths comparable to classical petroleum-based thermoplastics. They also exhibited high moduli, which is characteristic of brittle materials. A higher temperature and higher pressure rate produced specimens with higher mechanical properties while low moisture content produced weaker specimens. Generally, the strong specimen had higher specific gravity and lower moisture content. However, some parameters did not follow the general trend e.g., thinner specimen showed much higher Young’s Modulus, although their specific gravity and moisture content remained similar to control, revealing a marked skin-effect which was confirmed by SEM observations.

  19. High-yield production of extracellular type-I cellulose by the cyanobacterium Synechococcus sp. PCC 7002.

    Science.gov (United States)

    Zhao, Chi; Li, Zhongkui; Li, Tao; Zhang, Yingjiao; Bryant, Donald A; Zhao, Jindong

    2015-01-01

    Cellulose synthase, encoded by the cesA gene, is responsible for the synthesis of cellulose in nature. We show that the cell wall of the cyanobacterium Synechococcus sp. PCC 7002 naturally contains cellulose. Cellulose occurs as a possibly laminated layer between the inner and outer membrane, as well as being an important component of the extracellular glycocalyx in this cyanobacterium. Overexpression of six genes, cmc-ccp-cesAB-cesC-cesD-bgl, from Gluconacetobacter xylinus in Synechococcus sp. PCC 7002 resulted in very high-yield production of extracellular type-I cellulose. High-level cellulose production only occurred when the native cesA gene was inactivated and when cells were grown at low salinity. This system provides a method for the production of lignin-free cellulose from sunlight and CO2 for biofuel production and other biotechnological applications.

  20. Bacterial cellulose/boehmite composites

    Energy Technology Data Exchange (ETDEWEB)

    Salvi, Denise T.B. de; Barud, Hernane S.; Messaddeq, Younes; Ribeiro, Sidney J.L. [Universidade Estadual Paulista Julio de Mesquita Filho. UNESP. Instituto de Quimica de Araraquara, SP (Brazil); Caiut, Jose Mauricio A. [Universidade de Sao Paulo. Departamento de Quimica - FFCLRP/USP, Ribeirao Preto, SP (Brazil)

    2011-07-01

    Composites based on bacterial cellulose membranes and boehmite were obtained. SEM results indicate that the bacterial cellulose (BC) membranes are totally covered by boehmite and obtained XRD patterns suggest structural changes due to this boehmite addition. Thermal stability is accessed through TG curves and is dependent on boehmite content. Transparency is high comparing to pure BC as can be seen through UV-vis absorption spectroscopy. (author)

  1. Cytocompatible cellulose hydrogels containing trace lignin.

    Science.gov (United States)

    Nakasone, Kazuki; Kobayashi, Takaomi

    2016-07-01

    Sugarcane bagasse was used as a cellulose resource to prepare transparent and flexible cellulose hydrogel films. On the purification process from bagasse to cellulose, the effect of lignin residues in the cellulose was examined for the properties and cytocompatibility of the resultant hydrogel films. The cellulose was dissolved in lithium chloride/N,N-dimethylacetamide solution and converted to hydrogel films by phase inversion. In the purification process, sodium hydroxide (NaOH) treatment time was changed from 1 to 12h. This resulted in cellulose hydrogel films having small amounts of lignin from 1.62 to 0.68%. The remaining lignin greatly affected hydrogel properties. Water content of the hydrogel films was increased from 1153 to 1525% with a decrease of lignin content. Moreover, lower lignin content caused weakening of tensile strength from 0.80 to 0.43N/mm(2) and elongation from 45.2 to 26.5%. Also, similar tendency was observed in viscoelastic behavior of the cellulose hydrogel films. Evidence was shown that the lignin residue was effective for the high strength of the hydrogel films. In addition, scanning probe microscopy in the morphological observation was suggested that the trace lignin in the cellulose hydrogel affected the cellulose fiber aggregation in the hydrogel network. The trace of lignin in the hydrogels also influenced fibroblast cell culture on the hydrogel films. The hydrogel film containing 1.68% lignin showed better fibroblast compatibility as compared to cell culture polystyrene dish used as reference.

  2. PLLA-grafted cellulose nanocrystals: Role of the CNC content and grafting on the PLA bionanocomposite film properties.

    Science.gov (United States)

    Lizundia, Erlantz; Fortunati, Elena; Dominici, Franco; Vilas, José Luis; León, Luis Manuel; Armentano, Ilaria; Torre, Luigi; Kenny, Josè M

    2016-05-20

    Cellulose nanocrystals (CNC), extracted from microcrystalline cellulose by acid hydrolysis, were grafted by ring opening polymerization of L-Lactide initiated from the hydroxyl groups available at their surface and two different CNC:L-lactide ratios (20:80 and 5:95) were obtained. The resulting CNC-g-PLLA nanohybrids were incorporated in poly(lactic acid) (PLA) matrix by an optimized extrusion process at two different content (1 wt.% and 3 wt.%) and obtained bionanocomposite films were characterized by thermal, mechanical, optical and morphological properties. Thermal analysis showed CNC grafted with the higher ratio of lactide play a significant role as a nucleating agent. Moreover, they contribute to a significant increase in the crystallization rate of PLA, and the best efficiency was revealed with 3 wt.% of CNC-g-PLLA. This effect was confirmed by the increased in Young's modulus, suggesting the CNC graft ratio and content contribute significantly to the good dispersion in the matrix, positively affecting the final bionanocomposite properties.

  3. Cellulose/inorganic-composite fibers for producing textile fabrics of high X-ray absorption properties

    Energy Technology Data Exchange (ETDEWEB)

    Günther, Karoline; Giebing, Christina; Askani, Antonia [FTB, Hochschule Niederrhein – University of Applied Science, Faculty of Textile and Clothing Technology, Webschulstr. 31, 41065 Mönchengladbach (Germany); Leisegang, Tilmann [Saxray GmbH, Maria-Reiche-Str. 1, 01109 Dresden (Germany); Krieg, Marcus [TITK, Thüringisches Institut für Textil- und Kunststoff-Forschung e.V., Breitscheidstraße 97, 07407 Rudolstadt (Germany); Kyosev, Yordan; Weide, Thomas [FTB, Hochschule Niederrhein – University of Applied Science, Faculty of Textile and Clothing Technology, Webschulstr. 31, 41065 Mönchengladbach (Germany); Mahltig, Boris, E-mail: Boris.Mahltig@hs-niederrhein.de [FTB, Hochschule Niederrhein – University of Applied Science, Faculty of Textile and Clothing Technology, Webschulstr. 31, 41065 Mönchengladbach (Germany)

    2015-11-01

    Common textile materials as cotton or polyester do not possess reliable X-ray absorption properties. This is due to their morphology and chemical composition in particular. Common fibers are built up from organic polymers containing mainly the elements carbon, hydrogen, oxygen and nitrogen. These “light” elements only have low X-ray absorption coefficients. In contrast, inorganic materials composed of “heavy” elements with high atomic numbers, e.g. barium or bismuth, exhibit X-ray absorption coefficients higher by up to two orders of magnitude. To obtain a flexible yarn with high X-ray absorption properties both these materials, the organic polymer and the inorganic X-ray absorber, are combined to an inorganic/organic composite fiber material. Hence, as the organic component cellulose from modified Lyocell-process is used as carrier fiber and blended with inorganic absorber particles of low toxicity and high absorption coefficients, as bariumsulphate, bariumtitanate or bismuthoxide. A content of inorganic absorber particles equally distributed in the whole fiber of up to 20% is achieved. The composite fibers are produced as staple or filament fibers and processed to multifilament or staple fiber yarns. The staple fiber yarns are rotor-spinned to increase the comfort of the subsequent textile material. Several woven fabrics, considering multilayer structure and different warp/weft density, are developed. The energy dependent X-ray shielding properties are determined in dependence on the different yarn compositions, yarn types and structural parameters of the woven fabrics. As a result, a production process of textile materials with comfortable and dedicated X-ray absorption properties is established. It offers a promising opportunity for manufacturing of specialized textiles, working clothes or uniforms applicable for medicine, air craft and security personal, mining as well as for innovative composite materials. - Highlights: • Preparation of cellulosic

  4. Acid hydrolysis of cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, H.

    1980-12-01

    One of the alternatives to increase world production of etha nol is by the hydrolysis of cellulose content of agricultural residues. Studies have been made on the types of hydrolysis: enzimatic and acid. Data obtained from the sulphuric acid hydrolysis of cellulose showed that this process proceed in two steps, with a yield of approximately 95% glucose. Because of increases in cost of alternatives resources, the high demand of the product and the more economic production of ethanol from cellulose materials, it is certain that this technology will be implemented in the future. At the same time further studies on the disposal and reuse of the by-products of this production must be undertaken.

  5. Molecular weights of cellulose nitrates by osmotic pressure measurements

    Directory of Open Access Journals (Sweden)

    dr. V. Subramanyam

    1950-04-01

    Full Text Available It is well-known that nitro celluloses are employed for a variety of purposes. Broadly  nitrocellulose with relatively high nitrogen content are used in propellant and explosive manufacture nitrocelluloses  with lower nitrogen content find application in celluloid, in the lacquer industry, in cellulose paints, etc.

  6. Implications of Industrial Processing Strategy on Cellulosic Ethanol Production at High Solids Concentrations

    DEFF Research Database (Denmark)

    Cannella, David

    fermentation at high solids loading, in terms of maximized final conversion yield, is the overall aim of the work conducted. This thesis also revisits the knowledge already acquired in light of new enzymatic activities recently discovered i.e. lytic polysaccharides mono oxygenases (LPMOs), and how these ffects...... cellulosic ethanol processing at high solids conditions. Moreover for the first time in literature the activity of LPMOs on real lignocellulosic substrate and during cellulosic ethanol production is characterized. Hence describing the enzymatic scale dynamics when resembling in planta conditions, i...

  7. Modulation of the cellulose content of tuber cell walls by antisense expression of different potato (Solanum tuberosum L.) CesA clones.

    Science.gov (United States)

    Oomen, Ronald J F J; Tzitzikas, Emmanouil N; Bakx, Edwin J; Straatman-Engelen, Irma; Bush, Maxwell S; McCann, Maureen C; Schols, Henk A; Visser, Richard G F; Vincken, Jean-Paul

    2004-03-01

    Four potato cellulose synthase (CesA) homologs (StCesA1, 2, 3 and 4) were isolated by screening a cDNA library made from developing tubers. Based on sequence comparisons and the fact that all four potato cDNAs were isolated from this single cDNA-library, all four StCesA clones are likely to play a role in primary cell wall biosynthesis. Several constructs were generated to modulate cellulose levels in potato plants in which the granule-bound starch synthase promoter was used to target the modification to the tubers. The StCesA3 was used for up- and down-regulation of the cellulose levels by sense (SE-StCesA3) and antisense (AS-StCesA3) expression of the complete cDNA. Additionally, the class-specific regions (CSR) of all four potato cellulose synthase genes were used for specific down-regulation (antisense) of the corresponding CesA genes (csr1, 2, 3 and 4). None of the transformants showed an overt developmental phenotype. Sections of tubers were screened for altered cell wall structure by Fourier Transform Infrared microspectroscopy (FTIR) and exploratory Principal Component Analysis (PCA), and those plants discriminating from WT plants were analysed for cellulose content and monosaccharide composition. Several transgenic lines were obtained with mainly decreased levels of cellulose. These results show that the cellulose content in potato tubers can be reduced down to 40% of the WT level without affecting normal plant development, and that constructs based on the CSR alone are specific and sufficient to down-regulate cellulose biosynthesis.

  8. Highly flexible magnetic composite aerogels prepared by using cellulose nanofibril networks as templates.

    Science.gov (United States)

    Liu, Shilin; Yan, Qiufang; Tao, Dandan; Yu, Tengfei; Liu, Xiaoya

    2012-06-20

    Nanostructured cellulose nanofibrils can form ductile or tough networks that are suitable templates for the creation of materials with functional properties. In this work, a facile method has been developed for the preparation of magnetic hybrid cellulose aerogels. The preparation processes followed by two steps, firstly, preparation of cellulose hydrogel films from LiOH/urea solvent, then CoFe2O4 nanoparticles were synthesized in the porous structured cellulose scaffolds. After being freeze-dried, CoFe2O4/cellulose magnetic aerogels were obtained. The porosity of the composite aerogels ranged from 78 to 52% with pore size distribution in a few tens of nanometers. The internal specific surface areas were around 300-320 m2/g, and the densities were in the range of 0.25-0.39 g/cm3. The hybrid aerogels showed improved mechanical strength, superparamagnetic properties. Unlike solvent-swollen gels and ferrogels, the magnetic composite aerogels were lightweight, flexibility, high porosity and with large specific surface area and could be expected to be used in many fields. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Characterization and modeling of performance of Polymer Composites Reinforced with Highly Non-Linear Cellulosic Fibers

    Science.gov (United States)

    Rozite, L.; Joffe, R.; Varna, J.; Nyström, B.

    2012-02-01

    The behaviour of highly non-linear cellulosic fibers and their composite is characterized. Micro-mechanisms occurring in these materials are identified. Mechanical properties of regenerated cellulose fibers and composites are obtained using simple tensile test. Material visco-plastic and visco-elastic properties are analyzed using creep tests. Two bio-based resins are used in this study - Tribest and EpoBioX. The glass and flax fiber composites are used as reference materials to compare with Cordenka fiber laminates.

  10. High-Temperature Performance and Multiscale Damage Mechanisms of Hollow Cellulose Fiber-Reinforced Concrete

    Directory of Open Access Journals (Sweden)

    Liping Guo

    2016-01-01

    Full Text Available Spalling resistance properties and their damage mechanisms under high temperatures are studied in hollow cellulose fiber-reinforced concrete (CFRC used in tunnel structures. Measurements of mass loss, relative dynamic elastic modulus, compressive strength, and splitting tensile strength of CFRC held under high temperatures (300, 600, 800, and 1050°C for periods of 2.5, 4, and 5.5 h were carried out. The damage mechanism was analyzed using scanning electron microscopy, mercury intrusion porosimetry, thermal analysis, and X-ray diffraction phase analysis. The results demonstrate that cellulose fiber can reduce the performance loss of concrete at high temperatures; the effect of holding time on the performance is more noticeable below 600°C. After exposure to high temperatures, the performance of ordinary concrete deteriorates faster and spalls at 700–800°C; in contrast, cellulose fiber melts at a higher temperature, leaving a series of channels in the matrix that facilitate the release of the steam pressure inside the CFRC. Hollow cellulose fibers can thereby slow the damage caused by internal stress and improve the spalling resistance of concrete under high temperatures.

  11. High-performance supercapacitor electrode from cellulose-derived, inter-bonded carbon nanofibers

    Science.gov (United States)

    Cai, Jie; Niu, Haitao; Wang, Hongxia; Shao, Hao; Fang, Jian; He, Jingren; Xiong, Hanguo; Ma, Chengjie; Lin, Tong

    2016-08-01

    Carbon nanofibers with inter-bonded fibrous structure show high supercapacitor performance when being used as electrode materials. Their preparation is highly desirable from cellulose through a pyrolysis technique, because cellulose is an abundant, low cost natural material and its carbonization does not emit toxic substance. However, interconnected carbon nanofibers prepared from electrospun cellulose nanofibers and their capacitive behaviors have not been reported in the research literature. Here we report a facile one-step strategy to prepare inter-bonded carbon nanofibers from partially hydrolyzed cellulose acetate nanofibers, for making high-performance supercapacitors as electrode materials. The inter-fiber connection shows considerable improvement in electrode electrochemical performances. The supercapacitor electrode has a specific capacitance of ∼241.4 F g-1 at 1 A g-1 current density. It maintains high cycling stability (negligible 0.1% capacitance reduction after 10,000 cycles) with a maximum power density of ∼84.1 kW kg-1. They may find applications in the development of efficient supercapacitor electrodes for energy storage applications.

  12. Ultrarobust Transparent Cellulose Nanocrystal-Graphene Membranes with High Electrical Conductivity.

    Science.gov (United States)

    Xiong, Rui; Hu, Kesong; Grant, Anise M; Ma, Ruilong; Xu, Weinan; Lu, Canhui; Zhang, Xinxing; Tsukruk, Vladimir V

    2016-02-17

    Ultra-robust nanomembranes possessing high mechanical strength combined with excellent stiffness and toughness rarely achieved in nanocomposite materials are presented. These are fabricated by alternately depositing 1D cellulose nanocrystals and 2D graphene oxide nanosheets by using a spin assisted layer-by-layer assembly technique. Such a unique combination of 1D and 2D reinforcing nanostructures results in layered nanomaterials.

  13. The effect of high intensity mixing on the enzymatic hydrolysis of concentrated cellulose fiber suspensions

    Science.gov (United States)

    Joseph R. Samaniuk; C. Tim Scott; Thatcher W. Root; Daniel J. Klingenberg

    2011-01-01

    Enzymatic hydrolysis of lignocellulosic biomass in a high shear environment was examined. The conversion of cellulose to glucose in samples mixed in a torque rheometer producing shear flows similar to those found in twin screw extruders was greater than that of unmixed samples. In addition, there is a synergistic effect of mixing and enzymatic hydrolysis; mixing...

  14. Co-inoculating ruminal content neither provides active hydrolytic microbes nor improves methanization of ¹³C-cellulose in batch digesters.

    Science.gov (United States)

    Chapleur, Olivier; Bize, Ariane; Serain, Thibaut; Mazéas, Laurent; Bouchez, Théodore

    2014-03-01

    Cellulose hydrolysis often limits the kinetics and efficiency of anaerobic degradation in industrial digesters. In animal digestive systems, specialized microorganisms enable cellulose biodegradation at significantly higher rates. This study aims to assess the potential of ruminal microbial communities to settle and to express their cellulolytic properties in anaerobic digesters. Cellulose-degrading batch incubations were co-inoculated with municipal solid waste digester sludge and ruminal content. ¹³C-labeled cellulose degradation was described over time with Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry. Results were linked to the identification of the microorganisms assimilating ¹³C and to the monitoring of their relative dynamics. Cellulose degradation in co-inoculated incubations was efficient but not significantly improved. Transient disturbances in degradation pathways occurred, as revealed by propionate accumulation. Automated Ribosomal Intergenic Spacer Analysis dynamics and pyrosequencing revealed that expected classes of Bacteria and Archaea were active and degraded cellulose. However, despite the favorable co-inoculation conditions, molecular tools also revealed that no ruminal species settled in the bioreactors. Other specific parameters were probably needed for this to happen. This study shows that exploiting the rumen's cellulolytic properties in anaerobic digesters is not straightforward. Co-inoculation can only be successful if ruminal microorganisms manage to thrive in the anaerobic digester and outcompete native microorganisms, which requires specific nutritional and environmental parameters, and a meticulous reproduction of the selection pressure encountered in the rumen.

  15. High-flux Thin-film Nanofibrous Composite Ultrafiltration Membranes Containing Cellulose Barrier Layer

    Energy Technology Data Exchange (ETDEWEB)

    Ma, H.; Yoon, K; Rong, L; Mao, Y; Mo, Z; Fang, D; Hollander, Z; Gaiteri, J; Hsiao , B; Chu, B

    2010-01-01

    A novel class of thin-film nanofibrous composite (TFNC) membrane consisting of a cellulose barrier layer, a nanofibrous mid-layer scaffold, and a melt-blown non-woven substrate was successfully fabricated and tested as an ultrafiltration (UF) filter to separate an emulsified oil and water mixture, a model bilge water for on-board ship bilge water purification. Two ionic liquids: 1-butyl-3-methylimidazolium chloride and 1-ethyl-3-methylimidazolium acetate, were chosen as the solvent to dissolve cellulose under mild conditions. The regenerated cellulose barrier layer exhibited less crystallinity (determined by wide-angle X-ray diffraction, WAXD) than the original cotton linter pulps, but good thermal stability (determined by thermal gravimetric analysis, TGA). The morphology, water permeation, and mechanical stability of the chosen TFNCmembranes were thoroughly investigated. The results indicated that the polyacrylonitrile (PAN) nanofibrous scaffold was partially imbedded in the cellulose barrier layer, which enhanced the mechanical strength of the top barrier layer. The permeation flux of the cellulose-based TFNCmembrane was significantly higher (e.g. 10x) than comparable commercial UFmembranes (PAN10 and PAN400, Sepro) with similar rejection ratios for separation of oil/water emulsions. The molecular weight cut-off (MWCO) of TFNC membranes with cellulose barrier layer was evaluated using dextran feed solutions. The rejection was found to be higher than 90% with a dextran molecular weight of 2000 KDa, implying that the nominal pore size of the membrane was less than 50 nm. High permeation flux was also observed in the filtration of an emulsified oil/water mixture as well as of a sodium alginate aqueous solution, while high rejection ratio (above 99.5%) was maintained after prolonged operation. A variation of the barrier layer thickness could dramatically affect the permeation flux and the rejection ratio of the TFNCmembranes, while different sources of cellulose

  16. Nano-Structural Investigation on Cellulose Highly Dissolved in Ionic Liquid: A Small Angle X-ray Scattering Study

    Directory of Open Access Journals (Sweden)

    Takatsugu Endo

    2017-01-01

    Full Text Available We investigated nano-structural changes of cellulose dissolved in 1-ethyl-3-methylimidazolium acetate—an ionic liquid (IL—using a small angle X-ray scattering (SAXS technique over the entire concentration range (0–100 mol %. Fibril structures of cellulose disappeared at 40 mol % of cellulose, which is a significantly higher concentration than the maximum concentration of dissolution (24–28 mol % previously determined in this IL. This behavior is explained by the presence of the anion bridging, whereby an anion prefers to interact with multiple OH groups of different cellulose molecules at high concentrations, discovered in our recent work. Furthermore, we observed the emergence of two aggregated nano-structures in the concentration range of 30–80 mol %. The diameter of one structure was 12–20 nm, dependent on concentration, which is ascribed to cellulose chain entanglement. In contrast, the other with 4.1 nm diameter exhibited concentration independence and is reminiscent of a cellulose microfibril, reflecting the occurrence of nanofibrillation. These results contribute to an understanding of the dissolution mechanism of cellulose in ILs. Finally, we unexpectedly proposed a novel cellulose/IL composite: the cellulose/IL mixtures of 30–50 mol % that possess liquid crystallinity are sufficiently hard to be moldable.

  17. Increased water content in bacterial cellulose synthesized under rotating magnetic fields.

    Science.gov (United States)

    Fijałkowski, Karol; Żywicka, Anna; Drozd, Radosław; Junka, Adam Feliks; Peitler, Dorota; Kordas, Marian; Konopacki, Maciej; Szymczyk, Patrycja; Rakoczy, Rafał

    2017-01-01

    The current study describes properties of bacterial cellulose (BC) obtained from Komagataeibacter xylinus cultures exposed to the rotating magnetic field (RMF) of 50 Hz frequency and magnetic induction of 34 mT for controlled time during 6 days of cultivation. The experiments were carried out in the customized RMF exposure system adapted for biological studies. The obtained BC displayed an altered micro-structure, degree of porosity, and water-related parameters in comparison to the non-treated, control BC samples. The observed effects were correlated to the duration and the time of magnetic exposure during K. xylinus cultivation. The most preferred properties in terms of water-related properties were found for BC obtained in the setting, where RMF generator was switched off for the first 72 h of cultivation and switched on for the next 72 h. The described method of BC synthesis may be of special interest for the production of absorbent, antimicrobial-soaked dressings and carrier supports for the immobilization of microorganisms and proteins.

  18. Production of cellulosic ethanol from sugarcane bagasse by steam explosion: Effect of extractives content, acid catalysis and different fermentation technologies.

    Science.gov (United States)

    Neves, P V; Pitarelo, A P; Ramos, L P

    2016-05-01

    The production of cellulosic ethanol was carried out using samples of native (NCB) and ethanol-extracted (EECB) sugarcane bagasse. Autohydrolysis (AH) exhibited the best glucose recovery from both samples, compared to the use of both H3PO4 and H2SO4 catalysis at the same pretreatment time and temperature. All water-insoluble steam-exploded materials (SEB-WI) resulted in high glucose yields by enzymatic hydrolysis. SHF (separate hydrolysis and fermentation) gave ethanol yields higher than those obtained by SSF (simultaneous hydrolysis and fermentation) and pSSF (pre-hydrolysis followed by SSF). For instance, AH gave 25, 18 and 16 g L(-1) of ethanol by SHF, SSF and pSSF, respectively. However, when the total processing time was taken into account, pSSF provided the best overall ethanol volumetric productivity of 0.58 g L(-1) h(-1). Also, the removal of ethanol-extractable materials from cane bagasse had no influence on the cellulosic ethanol production of SEB-WI, regardless of the fermentation strategy used for conversion.

  19. Posidonia oceanica as a Renewable Lignocellulosic Biomass for the Synthesis of Cellulose Acetate and Glycidyl Methacrylate Grafted Cellulose

    Directory of Open Access Journals (Sweden)

    Elena Vismara

    2013-05-01

    Full Text Available High-grade cellulose (97% α-cellulose content of 48% crystallinity index was extracted from the renewable marine biomass waste Posidonia oceanica using H2O2 and organic peracids following an environmentally friendly and chlorine-free process. This cellulose appeared as a new high-grade cellulose of waste origin quite similar to the high-grade cellulose extracted from more noble starting materials like wood and cotton linters. The benefits of α-cellulose recovery from P. oceanica were enhanced by its transformation into cellulose acetate CA and cellulose derivative GMA-C. Fully acetylated CA was prepared by conventional acetylation method and easily transformed into a transparent film. GMA-C with a molar substitution (MS of 0.72 was produced by quenching Fenton’s reagent (H2O2/FeSO4 generated cellulose radicals with GMA. GMA grafting endowed high-grade cellulose from Posidonia with adsorption capability. GMA-C removes β-naphthol from water with an efficiency of 47%, as measured by UV-Vis spectroscopy. After hydrolysis of the glycidyl group to glycerol group, the modified GMA-C was able to remove p-nitrophenol from water with an efficiency of 92%, as measured by UV-Vis spectroscopy. α-cellulose and GMA-Cs from Posidonia waste can be considered as new materials of potential industrial and environmental interest.

  20. [Application of high-efficient cellulose utilization microorganisms in co-composting of vegetable wastes and flower stalk].

    Science.gov (United States)

    Huang, De-yang; Lu, Wen-jing; Wang, Hong-tao; Zhou, Hui-yu; Wang, Zhi-chao

    2004-03-01

    An inoculation composing 17 species of cellulose utilization microorganisms was used in co-composting of vegetable wastes and flower stalk, and the efficiency of the inoculation on lignocellulose degradation was studied. The experiments result show that at the beginning of the first stage of composting, inoculating cellulose utilization microorganism in the substrates with 0.5% (V/V) can improve the biomass of the microorganisms into the substrates greatly and make them dominant ones. When the temperature was controlled as 55 degrees C, the biomass of cellulose utilization microorganisms can keep between [symbol: see text] 3.84 x 10(9)-1.80 x 10(10) CFU/g. At the beginning of the second stage, inoculating with 1% (V/V) can improve the temperature during this period effectively. Monitoring of the content of lignocelluloses in the substrate shows that the inoculation of cellulose utilization microorganism can accelerate the degradation of cellulose. The degradation efficiency of cellulose under inoculation condition is 23.64% higher than those without inoculation. This shows that inoculating with cellulose utilization microorganisms in each stage of the composting can greatly decompose the lignocellulose in the substrates, accelerate the co-composting process and improve the quality of composting production.

  1. Cellulose Anionic Hydrogels Based on Cellulose Nanofibers As Natural Stimulants for Seed Germination and Seedling Growth.

    Science.gov (United States)

    Zhang, Hao; Yang, Minmin; Luan, Qian; Tang, Hu; Huang, Fenghong; Xiang, Xia; Yang, Chen; Bao, Yuping

    2017-05-17

    Cellulose anionic hydrogels were successfully prepared by dissolving TEMPO-oxidized cellulose nanofibers in NaOH/urea aqueous solution and being cross-linked with epichlorohydrin. The hydrogels exhibited microporous structure and high hydrophilicity, which contribute to the excellent water absorption property. The growth indexes, including the germination rate, root length, shoot length, fresh weight, and dry weight of the seedlings, were investigated. The results showed that cellulose anionic hydrogels with suitable carboxylate contents as plant growth regulators could be beneficial for seed germination and growth. Moreover, they presented preferable antifungal activity during the breeding and growth of the sesame seed breeding. Thus, the cellulose anionic hydrogels with suitable carboxylate contents could be applied as soilless culture mediums for plant growth. This research provided a simple and effective method for the fabrication of cellulose anionic hydrogel and evaluated its application in agriculture.

  2. Direct enantioseparation of nitrogen-heterocyclic pesticides on cellulose-based chiral column by high-performance liquid chromatography.

    Science.gov (United States)

    Chai, Tingting; Yang, Wenwen; Qiu, Jing; Hou, Shicong

    2015-01-01

    The enantiomeric separation of eight pesticides including bitertanol (), diclobutrazol (), fenbuconazole (), triticonazole (), imazalil (), triapenthenol (), ancymidol (), and carfentrazone-ethyl () was achieved, using normal-phase high-performance liquid chromatography on two cellulosed-based chiral columns. The effects of isopropanol composition from 2% to 30% in the mobile phase and column temperature from 5 to 40 °C were investigated. Satisfactory resolutions were obtained for bitertanol (), triticonazole (), imazalil () with the (+)-enantiomer eluted first and fenbuconazole () with the (-)-enantiomer eluted first on Lux Cellulose-2 and Lux Cellulose-3. (+)-Enantiomers of diclobutrazol () and triapenthenol () were first eluted on Lux Cellulose-2. (-)-Carfentrazone-ethyl () were eluted first on Lux Cellulose-2 and Lux Cellulose-3 with incomplete separation. Reversed elution orders were obtained for ancymidol (7). (+)-Ancymidol was first eluted on Lux Cellulose-2 while on Lux Cellulose-3 (-)-ancymidol was first eluted. The results of the elution order at different column temperatures suggested that column temperature did not affect the optical signals of the enantiomers. These results will be helpful to prepare and analyze individual enantiomers of chiral pesticides.

  3. Development of wet-dry reversible reverse osmosis membrane with high performance from cellulose acetate and cellulose triactate blend

    NARCIS (Netherlands)

    Vasarhelyi, K.; Ronner, J.A.; Mulder, M.H.V.; Smolders, C.A.

    1987-01-01

    Wet-dry reversible membrane were prepared bt a two-step coagulation procedure. A cast film containing a blend of cellulose triacetate as polymers, dioxane and acetone as solvents and maleic acid and methanol as additives was immersed consecutively in two aqueous coagulation baths, the first bath bei

  4. Characterization of the crystalline structure of cellulose using static and dynamic FT-IR spectroscopy.

    Science.gov (United States)

    Akerholm, Margaretha; Hinterstoisser, Barbara; Salmén, Lennart

    2004-02-25

    The cellulose structure is a factor of major importance for the strength properties of wood pulp fibers. The ability to characterize small differences in the crystalline structures of cellulose from fibers of different origins is thus highly important. In this work, dynamic FT-IR spectroscopy has been further explored as a method sensitive to cellulose structure variations. Using a model system of two different celluloses, the relation between spectral information and the relative cellulose Ialpha content was investigated. This relation was then used to determine the relative cellulose Ialpha content in different pulps. The estimated cellulose I allomorph compositions were found to be reasonable for both unbleached and bleached chemical pulps. In addition, it was found that the dynamic FT-IR spectroscopy technique had the potential to indicate possible correlation field splitting peaks of cellulose Ibeta.

  5. Strength of cellulosic fiber/starch acetate composites with variable fiber and plasticizer content

    DEFF Research Database (Denmark)

    Joffe, Roberts; Madsen, Bo; Nättinen, Kalle

    2015-01-01

    In this experimental study, the performance of injection-molded short flax and hemp fibers in plasticized starch acetate were analyzed in terms of strength. Parameters involved in the analysis are a variable fiber and plasticizer content. The measured strength of the composites varies in the rang...

  6. Effect of Water Content in N-Methylmorpholine N-Oxide/Cellulose Solutions on Thermodynamics, Structure, and Hydrogen Bonding.

    Science.gov (United States)

    Rabideau, Brooks D; Ismail, Ahmed E

    2015-12-03

    Native crystalline cellulose is notoriously difficult to dissolve due to its dense hydrogen bond network between chains and weaker hydrophobic forces between cellulose sheets. N-Methylmorpholine N-oxide (NMMO), the solvent behind the Lyocell process, is one of the most successful commercial solvents for the nonderivatized dissolution of cellulose. In this process, water plays a very important role. Its presence at low concentrations allows NMMO to dissolve substantial amounts of cellulose, while at much higher concentrations it precipitates the crystalline fibers. Using all-atom molecular dynamics, we study the thermodynamic and structural properties of ternary solutions of cellulose, NMMO, and water. Using the two-phase thermodynamic method to calculate solvent entropy, we estimate the free energy of dissolution of cellulose as a function of the water concentration and find a transition of spontaneity that is in excellent agreement with experiment. In pure water, we find that cellulose dissolution is nonspontaneous, a result that is due entirely to strong decreases in water entropy. Although the combined effect of enthalpy on dissolution in water is negligible, we observe a net loss of hydrogen bonds, resulting in a change in hydrogen bond energy that opposes dissolution. At lower water concentrations, cellulose dissolution is spontaneous and largely driven by decreases in enthalpy, with solvent entropy playing only a very minor role. When searching for the root causes of this enthalpy decrease, a complex picture emerges in which not one but many different factors contribute to NMMO's good solvent behavior. The reduction in enthalpy is led by the formation of strong hydrogen bonds between cellulose and NMMO's N-oxide, intensified through van der Waals interactions between NMMO's nonpolar body and the nonpolar surfaces of cellulose and unhindered by water at low concentrations due to the formation of efficient hydrogen bonds between water and cellulose.

  7. The Effects of CaCO3 Coated Wood Free Paper Usage as Filler on Water Absorption, Mechanical and Thermal Properties of Cellulose-High Density Polyethylene Composites

    Directory of Open Access Journals (Sweden)

    Emrah PEŞMAN

    2016-11-01

    Full Text Available In this study some physical, mechanical and thermal characteristics of high density polyethylene (HDPE and CaCO3 coated/pigmented wood free paper fiber composites were investigated. The fillers used in this study were uncoated cellulose, 5.8 %, 11.5 %, 16.5 % and 23.1 % CaCO3 coated wood free paper fibers. Each filler type was mixed with HDPE at 40% by weight fiber loading. In this case, the ratio of CaCO3 in plastic composites were calculated as 0 %, 2.3 %, 4.6 %, 6.6 % and 9.2 % respectively. Increased CaCO3 ratio improved the moisture resistant, flexural and tensile strength of cellulose-HDPE composites. However, the density of the cellulose-HDPE composites increased with CaCO3 addition. Energy Dispersive Spectroscopy on Scanning Electron Microscope analysis demonstrated the uniform distribution of CaCO3 and cellulose fiber in plastic matrix. In addition, the thermal properties of fiber plastic composites were investigated. The results of Differential scanning calorimetry analysis revealed that the crystallinity of the samples decreased with increasing CaCO3 content. Consequently, this work showed that CaCO3 coated waste paper fibers could be used as reinforcing filler against water absorption in thermoplastic matrix.DOI: http://dx.doi.org/10.5755/j01.ms.22.4.14222

  8. High-Performance Supercapacitor Electrode Materials from Cellulose-Derived Carbon Nanofibers.

    Science.gov (United States)

    Cai, Jie; Niu, Haitao; Li, Zhenyu; Du, Yong; Cizek, Pavel; Xie, Zongli; Xiong, Hanguo; Lin, Tong

    2015-07-15

    Nitrogen-functionalized carbon nanofibers (N-CNFs) were prepared by carbonizing polypyrrole (PPy)-coated cellulose NFs, which were obtained by electrospinning, deacetylation of electrospun cellulose acetate NFs, and PPy polymerization. Supercapacitor electrodes prepared from N-CNFs and a mixture of N-CNFs and Ni(OH)2 showed specific capacitances of ∼236 and ∼1045 F g(-1), respectively. An asymmetric supercapacitor was further fabricated using N-CNFs/Ni(OH)2 and N-CNFs as positive and negative electrodes. The supercapacitor device had a working voltage of 1.6 V in aqueous KOH solution (6.0 M) with an energy density as high as ∼51 (W h) kg(-1) and a maximum power density of ∼117 kW kg(-1). The device had excellent cycle lifetime, which retained ∼84% specific capacitance after 5000 cycles of cyclic voltammetry scans. N-CNFs derived from electrospun cellulose may be useful as an electrode material for development of high-performance supercapacitors and other energy storage devices.

  9. Ultradrawing novel ultra-high molecular weight polyethylene fibers filled with bacterial cellulose nanofibers.

    Science.gov (United States)

    Yeh, Jen-Taut; Tsai, Chih-Chen; Wang, Chuen-Kai; Shao, Jhih-Wun; Xiao, Ming-Zheng; Chen, Su-Chen

    2014-01-30

    Novel ultrahigh molecular weight polyethylene (UHMWPE)/bacterial cellulose (BC) (F100BCy) and UHMWPE/modified bacterial cellulose (MBC) (F100MBCx-y) as-prepared fibers were prepared and ultra-drawn. The achievable draw ratio (Dra) values of each F100MBCx-y as-prepared fiber series specimens approached a maximum value as their MBC contents reached the optimal value at 0.0625phr. In which, the maximum Dra value obtained for F100MBCx-0.0625 as-prepared fiber specimen prepared at the optimal MBC content reached another maximum value at 347 as the weight ratio of maleic anhydride grafted polyethylene to BC approach an optimal value at 10. In contrast, no significant improvement in Dra values was found for F100BCy as-prepared fiber specimens. To understand these interesting ultradrawing properties described above, Fourier transform infra-red, specific surface areas, and transmission electron microcopic analyses of original and modified BC nanofibers together with the thermal, orientation and tensile properties of F100BCy and F100MBCx-y fiber specimens were performed.

  10. Reinforcement of all-cellulose nanocomposite films using native cellulose nanofibrils.

    Science.gov (United States)

    Zhao, Jiangqi; He, Xu; Wang, Yaru; Zhang, Wei; Zhang, Xinxing; Zhang, Xiaodan; Deng, Yulin; Lu, Canhui

    2014-04-15

    All-cellulose nanocomposite films were prepared using native cellulose nanofibrils (CNFs) as fillers and lithium chloride/N,N-dimethylacetamide (LiCl/DMAc) dissolved regenerated cellulose as the matrix. The CNFs, with diameters in the range of 15-40 nm were obtained by combined physical methods of ultrasonic treatment and high shear homogenization. The morphology, structure, and properties of the nanocomposite films were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), optical transmittance, thermal gravimetric analysis (TGA), and mechanical testing. The nanocomposite films exhibited good optical transparency, thermal stability, and remarkably enhanced mechanical properties compared to the regenerated cellulose matrix. By varying the CNFs content, the tensile strength of the nanocomposite films increased from 61.56 MPa to 99.92 MPa and the Young's modulus increased from 0.76 GPa to 4.16 GPa. This work provided a promising pathway for manufacturing high performance and environmental-friendly all-cellulose nanocomposites.

  11. High effective adsorption of organic dyes on magnetic cellulose beads entrapping activated carbon.

    Science.gov (United States)

    Luo, Xiaogang; Zhang, Lina

    2009-11-15

    Maghemite (gamma-Fe(2)O(3)) nanoparticles were created with a submerged circulation impinging stream reactor (SCISR) from FeCl(3) x 6H(2)O and FeCl(2).4H(2)O by using precipitation followed by oxidation. Subsequently, by blending cellulose with the Fe(2)O(3) nanoparticles and activated carbon (AC) in 7 wt% NaOH/12 wt% urea aqueous solution pre-cooled to -12 degrees C, millimeter-scale magnetic cellulose beads, coded as MCB-AC, was fabricated via an optimal dropping technology. The cellulose beads containning Fe(2)O(3) nanoparticles exhibited sensitive magnetic response, and their recovery could facilitate by applying a magnetic field. The adsorption and desorption of the organic dyes on MCB-AC were investigated to evaluate the removal of dyes (methyl orange and methylene blue) with different charges from aqueous solution. Their adsorption kinetics experiments were carried out and the data were well fitted by a pseudo-second-order equation. The results revealed that the MCB-AC sorbent could efficiently adsorb the organic dyes from wastewater, and the used sorbents could be recovered completely. Therefore, we developed a highly efficient sorbent, which were prepared by using simple and "green" process, for the applications on the removal of hazardous materials.

  12. A reactor for high-temperature pyrolysis and oxygen isotopic analysis of cellulose via induction heating.

    Science.gov (United States)

    Evans, Michael N

    2008-07-01

    A reactor for converting cellulose into carbon monoxide for subsequent oxygen isotopic analysis via continuous flow isotope ratio mass spectrometry is described. The system employs an induction heater to produce temperatures >or=1500 degrees C within a molybdenum foil crucible positioned by boron nitride (BN) spacers within a quartz outer sleeve. For samples of a homogeneous working standard cellulose between 300 and 400 microg in size, the blank/signal ratio is <5%, and the long-term precision is 0.30 per thousand (N = 232). For samples of 30 to 100 microg in size, a gas pressure sintered silicon nitride (Si(3)N(4)) outer sleeve replaces the quartz sleeve, the BN spacers are not used, and 6.0-grade carrier He must be used to minimize the blank signal. With these modifications a blank/sample ratio of <5% and long-term precision of 0.30 per thousand (N = 144) are obtained. These results are similar to those achieved using standard high-temperature furnaces, but the reactor is simpler to pack, the system is more economical to run, and samples as small as 30 microg cellulose may be measured. For both reactors memory is significant in the subsequent sample and is believed to be due to exchange with reactor oxygen at temperatures above 1000 degrees C. Further applications might include online preparation of other materials requiring temperatures of 1500-2600 degrees C.

  13. High effective adsorption of organic dyes on magnetic cellulose beads entrapping activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Luo Xiaogang [Department of Chemistry, Wuhan University, Wuhan 430072 (China); Zhang Lina, E-mail: lnzhang@public.wh.hb.cn [Department of Chemistry, Wuhan University, Wuhan 430072 (China)

    2009-11-15

    Maghemite ({gamma}-Fe{sub 2}O{sub 3}) nanoparticles were created with a submerged circulation impinging stream reactor (SCISR) from FeCl{sub 3}.6H{sub 2}O and FeCl{sub 2}.4H{sub 2}O by using precipitation followed by oxidation. Subsequently, by blending cellulose with the Fe{sub 2}O{sub 3} nanoparticles and activated carbon (AC) in 7 wt% NaOH/12 wt% urea aqueous solution pre-cooled to -12 deg. C, millimeter-scale magnetic cellulose beads, coded as MCB-AC, was fabricated via an optimal dropping technology. The cellulose beads containning Fe{sub 2}O{sub 3} nanoparticles exhibited sensitive magnetic response, and their recovery could facilitate by applying a magnetic field. The adsorption and desorption of the organic dyes on MCB-AC were investigated to evaluate the removal of dyes (methyl orange and methylene blue) with different charges from aqueous solution. Their adsorption kinetics experiments were carried out and the data were well fitted by a pseudo-second-order equation. The results revealed that the MCB-AC sorbent could efficiently adsorb the organic dyes from wastewater, and the used sorbents could be recovered completely. Therefore, we developed a highly efficient sorbent, which were prepared by using simple and 'green' process, for the applications on the removal of hazardous materials.

  14. The Effect of Chemical and High-Pressure Homogenization Treatment Conditions on the Morphology of Cellulose Nanoparticles

    Directory of Open Access Journals (Sweden)

    Suxia Ren

    2014-01-01

    Full Text Available Cellulose nanoparticles were fabricated from microcrystalline cellulose (MCC through combined acid hydrolysis with sulfuric and hydrochloric acids and high-pressure homogenization. The effect of acid type, acid-to-MCC ratio, reaction time, and numbers of high-pressure homogenization passes on morphology and thermal stability of the nanoparticles was studied. An aggressive acid hydrolysis was shown to lead to rod-like cellulose nanocrystals with diameter about 10 nm and lengths in the range of 50–200 nm. Increased acid-to-MCC ratio and number of homogenization treatments reduced the dimension of the nanocrystals produced. Weak acid hydrolysis treatment led to a network of cellulose nanofiber bundles having diameters in the range of 20–100 nm and lengths of a few thousands of nanometers. The high-pressure homogenization treatment helped separate the nanofiber bundles. The thermal degradation behaviors characterized by thermogravimetric analysis at nitrogen atmosphere indicated that the degradation of cellulose nanocrystals from sulfuric acid hydrolysis started at a lower temperature and had two remarkable pyrolysis processes. The thermal stability of cellulose nanofibers produced from hydrochloric acid hydrolysis improved significantly.

  15. Highly durable, biomimetic electro-active paper actuator based on cellulose polypyrrole-ionic liquid (CPIL) nanocomposite.

    Science.gov (United States)

    Mahadeva, Suresha K; Yun, Kiju; Kim, Jaehwan; Kim, Joo-Hyung

    2011-01-01

    Cellulose has received much attention as a emerging smart material, named as electro-active paper (EAPap), which can produce a large bending displacement with applied external electrical field. In spite of many advantages over other reported electro active polymers, there are some issues to be addressed: its actuator performance: (i) sensitive to environmental humidity, (ii) humidity dependent displacement output of the actuator and (iii) degradation of performance with time. In present paper, we have successfully developed the highly durable EAPap actuator working at ambient condition with large displacement output. To improve the performance and durability of EAPap, nanoscaled PPy layer into cellulose EAPap was formed by in-situ polymerization technique. Cellulose-PPy-IL nanocomposite based EAPap actuator showed nearly 100% improvement of the actuator performance compared that of pure cellulose based EAPap actuator systems.

  16. High Efficiency DNA Extraction by Graphite Oxide/Cellulose/Magnetite Composites Under Na+ Free System

    Science.gov (United States)

    Akceoglu, Garbis Atam; Li, Oi Lun; Saito, Nagahiro

    2016-04-01

    DNA extraction is the key step at various research areas like biotechnology, diagnostic development, paternity determination, and forensic science . Solid support extraction is the most common method for DNA purification. In this method, Na+ ions have often been applied as binding buffers in order to obtain high extraction efficiency and high quality of DNA; however, the presence of Na+ ions might be interfering with the downstream DNA applications. In this study, we proposed graphite oxide (GO)/magnetite composite/cellulose as an innovative material for Na+-free DNA extraction. The total wt.% of GO was fixed at 4.15% in the GO/cellulose/magnetite composite . The concentration of magnetite within the composites were controlled at 0-3.98 wt.%. The extraction yield of DNA increased with increasing weight percentage of magnetite. The highest yield was achieved at 3.98 wt.% magnetite, where the extraction efficiency was reported to be 338.5 ng/µl. The absorbance ratios between 260 nm and 280 nm (A260/A280) of the DNA elution volume was demonstrated as 1.81, indicating the extracted DNA consisted of high purity. The mechanism of adsorption of DNA was provided by (1) π-π interaction between the aromatic ring in GO and nucleobases of DNA molecule, and (2) surface charge interaction between the positive charge magnetite and anions such as phosphates within the DNA molecules. The results proved that the GO/cellulose/magnetite composite provides a Na+-free method for selective DNA extraction with high extraction efficiency of pure DNA.

  17. Interfacial Engineering of Silicon Carbide Nanowire/Cellulose Microcrystal Paper toward High Thermal Conductivity.

    Science.gov (United States)

    Yao, Yimin; Zeng, Xiaoliang; Pan, Guiran; Sun, Jiajia; Hu, Jiantao; Huang, Yun; Sun, Rong; Xu, Jian-Bin; Wong, Ching-Ping

    2016-11-16

    Polymer composites with high thermal conductivity have attracted much attention, along with the rapid development of electronic devices toward higher speed and better performance. However, high interfacial thermal resistance between fillers and matrix or between fillers and fillers has been one of the primary bottlenecks for the effective thermal conduction in polymer composites. Herein, we report on engineering interfacial structure of silicon carbide nanowire/cellulose microcrystal paper by generating silver nanostructures. We show that silver nanoparticle-deposited silicon carbide nanowires as fillers can effectively enhance the thermal conductivity of the matrix. The in-plane thermal conductivity of the resultant composite paper reaches as high as 34.0 W/m K, which is one order magnitude higher than that of conventional polymer composites. Fitting the measured thermal conductivity with theoretical models qualitatively demonstrates that silver nanoparticles bring the lower interfacial thermal resistances both at silicon carbide nanowire/cellulose microcrystal and silicon carbide nanowire/silicon carbide nanowire interfaces. This interfacial engineering approach provides a powerful tool for sophisticated fabrication of high-performance thermal-management materials.

  18. Vibrational Spectral Signatures of Crystalline Cellulose Using High Resolution Broadband Sum Frequency Generation Vibrational Spectroscopy (HR-BB-SFG-VS)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Libing; Lu, Zhou; Velarde Ruiz Esparza, Luis A.; Fu, Li; Pu, Yunqiao; Ding, Shi-You; Ragauskas, Art J.; Wang, Hongfei; Yang, Bin

    2015-03-03

    Here we reported the first sub-wavenumber high-resolution broadband sum frequency generation vibrational spectroscopy (HR-BB-SFG-VS) study on both the C-H and O-H region spectra of crystalline cellulose. HR-BB-SFG-VS has about 10 times better resolution than the conventional scanning SFG-VS and is known to be able to measure the intrinsic spectral lineshape and to resolve much more spectral details. With HR-BB-SFG-VS, we found that in cellulose from different sources, including Avicel and cellulose crystals isolated from algae Valonia (Iα) and tunicates (Iβ), the spectral signatures in the OH regions were unique for different allomorphs, i.e. Iα and Iβ, while the spectral signatures in the C-H regions varied in all samples examined. Even though the origin of the different behaviors of the crystalline cellulose in the O-H and C-H vibrational frequency regions is yet to be correlated to the structure of cellulose, these results provided new spectroscopic methods and opportunities to classify and understand the basic crystalline structure, as well as variations, in polymorphism of the crystalline cellulose structure.

  19. High-performance symmetric supercapacitors based on carbon nanosheets framework with graphene hydrogel architecture derived from cellulose acetate

    Science.gov (United States)

    An, Yufeng; Yang, Yuying; Hu, Zhongai; Guo, Bingshu; Wang, Xiaotong; Yang, Xia; Zhang, Quancai; Wu, Hongying

    2017-01-01

    Three-dimensional nitrogen-doped carbon nanosheets framework (N-CNF) has been obtained starting with cellulose acetate. The product is prepared through a so-called one-step method that carbonization, activation and nitrogen-doping occur simultaneously. The resultant N-CNF shows an architecture like graphene hydrogel with interconnected hierarchical porous structure, N-doping with high nitrogen content (8.7 wt%) and high specific surface area (1003.6 m2 g-1). The N-CNF electrode displays excellent electrochemical performances due to the unique architecture and pseudocapacitance contribution from heteroatoms. In the three-electrode configuration, the N-GNF achieves a high specific capacitance of 242 F g-1 at 1 A g-1 and displays ultrahigh rate capability (83.4% capacitance retention at 100 A g-1) in 6 mol L-1 KOH electrolyte. The symmetric supercapacitor (SSC) based N-CNF exhibits energy density as high as 60.4 Wh kg-1 (at a power density of 1750 W kg-1) and 17.9 Wh kg-1 (at 850 W kg-1) in ionic liquid and aqueous electrolytes, respectively. It is surprised that the single device filled by ionic liquid electrolyte is able to light easily 60 red light-emitting diodes (LEDs, 2.2 V) in parallel after charging for only 10 s, showing an excellent energy storage/release performance.

  20. Preparation of cellulose nanocrystals from Humulus japonicus stem and the influence of high temperature pretreatment.

    Science.gov (United States)

    Jiang, Yani; Zhou, Jiping; Zhang, Qi; Zhao, Guoqi; Heng, Lin; Chen, Dongdong; Liu, Dongfang

    2017-05-15

    As one of the most abundant wild herbs in nature, the Humulus japonicus stem (HJS) is a new low-cost source of cellulosic material. In this work, cellulose nanocrystals (CNCs) were isolated from HJS using acid hydrolysis. The influence of high temperature pretreatment (HT pretreatment) on the properties and yields of these HT-HJS (HJS fibers after HT pretreatment at different temperatures) and HT-CNCs (CNCs prepared from the HT-HJS) was studied. The results showed that there was no variation of the chemical structure among the HT-HJS and HT-CNCs. The thermal stabilities and crystallinities of the HT-HJS were higher than bleached HJS. The average diameters of the HT-CNCs were significantly smaller while the average aspect ratios of them were obviously bigger than the CNCs, and the biggest average aspect ratio of HT140-CNCs (63.40) was almost twice of CNCs (32.00). Compared with the CNCs (70.05%, 212.8°C), the crystallinity and initial degradation temperature also showed increase for the HT-CNCs and increased up to maximum of 86.93% and 227.5°C for the HT160-CNCs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Ethanol production from high cellulose concentration by the basidiomycete fungus Flammulina velutipes.

    Science.gov (United States)

    Maehara, Tomoko; Ichinose, Hitomi; Furukawa, Takanori; Ogasawara, Wataru; Takabatake, Koji; Kaneko, Satoshi

    2013-03-01

    Ethanol production by Flammulina velutipes from high substrate concentrations was evaluated. F. velutipes produces approximately 40-60 g l(-1) ethanol from 15% (w/v) D-glucose, D-fructose, D-mannose, sucrose, maltose, and cellobiose, with the highest conversion rate of 83% observed using cellobiose as a carbon source. We also attempted to assess direct ethanol fermentation from sugarcane bagasse cellulose (SCBC) by F. velutipes. The hydrolysis rate of 15% (w/v) SCBC with commercial cellulase was approximately 20%. In contrast, F. velutipes was able to produce a significant amount of ethanol from 15% SCBC with the production of β-glucosidase, cellobohydrolase, and cellulase, although the addition of a small amount of commercial cellulase to the culture was required for the conversion. When 9 mg g(-1) biomass of commercial cellulase was added to cultures, 0.36 g of ethanol was produced from 1 g of cellulose, corresponding to an ethanol conversion rate of 69.6%. These results indicate that F. velutipes would be useful for consolidated bioprocessing of lignocellulosic biomass to bioethanol.

  2. Cellulose functionalization via high-energy irradiation-initiated grafting of glycidyl methacrylate and cyclodextrin immobilization

    Science.gov (United States)

    Desmet, Gilles; Takács, Erzsébet; Wojnárovits, László; Borsa, Judit

    2011-12-01

    Cotton-cellulose was functionalized using gamma-irradiation-induced grafting of glycidyl methacrylate (GMA) to obtain a hydrophobic cellulose derivative with epoxy groups suitable for further chemical modification. Two grafting techniques were applied. In pre-irradiation grafting (PIG) cellulose was irradiated in air and then immersed in a GMA monomer solution, whereas in simultaneous grafting (SG) cellulose was irradiated in an inert atmosphere in the presence of the monomer. PIG led to a more homogeneous fiber surface, while SG resulted in higher grafting yield but showed clear indications of some GMA-homopolymerization. Effects of the reaction parameters (grafting method, absorbed dose, monomer concentration, solvent composition) were evaluated by SEM, gravimetry (grafting yield) and FTIR spectroscopy. Water uptake of the cellulose decreased while adsorption of a pesticide molecule increased upon grafting. The adsorption was further enhanced by β-cyclodextrin immobilization during SG. This method can be applied to produce adsorbents from cellulose based agricultural wastes.

  3. Cellulose Nanofibril Based-Aerogel Microreactors: A High Efficiency and Easy Recoverable W/O/W Membrane Separation System

    OpenAIRE

    Fang Zhang; Hao Ren; Jing Dou; Guolin Tong; Yulin Deng

    2017-01-01

    Hereby we report a novel cellulose nanofirbril aerogel-based W/O/W microreactor system that can be used for fast and high efficient molecule or ions extraction and separation. The ultra-light cellulose nanofibril based aerogel microspheres with high porous structure and water storage capacity were prepared. The aerogel microspheres that were saturated with stripping solution were dispersed in an oil phase to form a stable water-in-oil (W/O) suspension. This suspension was then dispersed in la...

  4. Achieving a Collapsible, Strong, and Highly Thermally Conductive Film Based on Oriented Functionalized Boron Nitride Nanosheets and Cellulose Nanofiber.

    Science.gov (United States)

    Wu, Kai; Fang, Jinchao; Ma, Jinrui; Huang, Rui; Chai, Songgang; Chen, Feng; Fu, Qiang

    2017-09-06

    Boron nitride nanosheet (BNNS) films receive wide attention in both academia and industry because of their high thermal conductivity (TC) and good electrical insulation capability. However, the brittleness and low strength of the BNNS film largely limit its application. Herein, functionalized BNNSs (f-BNNSs) with a well-maintained in-plane crystalline structure were first prepared utilizing urea in the aqueous solution via ball-milling for the purpose of improving their stability in water and enhancing the interaction with the polymer matrix. Then, a biodegradable and highly thermally conductive film with an orderly oriented structure based on cellulose nanofibers (CNFs) and f-BNNSs was prepared just by simple vacuum-assisted filtration. The modification of the BNNS and the introduction of the CNF result in a better orientation of the f-BNNS, sufficient connection between f-BNNS themselves, and strong interaction between f-BNNS and CNF, which not only make the prepared composite film strong and tough but also possess higher in-plane TC. An increase of 70% in-plane TC, 63.2% tensile strength, and 77.8% elongation could be achieved for CNF/f-BNNS films, compared with that for CNF/BNNS films at the filler content of 70%. Although at such a high f-BNNS content, this composite film can be bended and folded. It is even more interesting to find that the in-plane TC could be greatly enhanced with the decrease of the thickness of the film, and a value of 30.25 W/m K can be achieved at the thickness of ∼30 μm for the film containing 70 wt % f-BNNS. We believe that this highly thermally conductive film with good strength and toughness could have potential applications in next-generation highly powerful and collapsible electronic devices.

  5. New aluminium alloys with high lithium content

    Energy Technology Data Exchange (ETDEWEB)

    Schemme, K.; Velten, B.

    1989-06-01

    Since the early 80's there have been made great efforts to replace the high strength aluminium alloys for the aircraft and space industry by a new generation of aluminium-lithium alloys. The attractivity of this kind of alloys could be increased by a further reduction of their density, caused by an increasing lithium content (/ge/ 5 wt.% Li). Therefore binary high-lithium containing alloys with low density are produced and metallografically investigated. A survey of their strength and wear behavior is given by using tensile tests and pin abrasing tests. (orig.).

  6. Catalytic oxidative conversion of cellulosic biomass to formic acid and acetic acid with exceptionally high yields

    KAUST Repository

    Zhang, Jizhe

    2014-09-01

    Direct conversion of raw biomass materials to fine chemicals is of great significance from both economic and ecological perspectives. In this paper, we report that a Keggin-type vanadium-substituted phosphomolybdic acid catalyst, namely H4PVMo11O40, is capable of converting various biomass-derived substrates to formic acid and acetic acid with high selectivity in a water medium and oxygen atmosphere. Under optimized reaction conditions, H4PVMo11O40 gave an exceptionally high yield of formic acid (67.8%) from cellulose, far exceeding the values achieved in previous catalytic systems. Our study demonstrates that heteropoly acids are generally effective catalysts for biomass conversion due to their strong acidities, whereas the composition of metal addenda atoms in the catalysts has crucial influence on the reaction pathway and the product selectivity. © 2013 Elsevier B.V.

  7. Polymethylsilsesquioxane-cellulose nanofiber biocomposite aerogels with high thermal insulation, bendability, and superhydrophobicity.

    Science.gov (United States)

    Hayase, Gen; Kanamori, Kazuyoshi; Abe, Kentaro; Yano, Hiroyuki; Maeno, Ayaka; Kaji, Hironori; Nakanishi, Kazuki

    2014-06-25

    Polymethylsilsesquioxane-cellulose nanofiber (PMSQ-CNF) composite aerogels have been prepared through sol-gel in a solvent containing a small amount of CNFs as suspension. Since these composite aerogels do not show excessive aggregation of PMSQ and CNF, the original PMSQ networks are not disturbed. Composite aerogels with low density (0.020 g cm(-3) at lowest), low thermal conductivity (15 mW m(-1) K(-1)), visible light translucency, bending flexibility, and superhydrophobicity thus have been successfully obtained. In particular, the lowest density and bending flexibility have been achieved with the aid of the physical supporting effect of CNFs, and the lowest thermal conductivity is comparable with the original PMSQ aerogels and standard silica aerogels. The PMSQ-CNF composite aerogels would be a candidate to practical high-performance thermal insulating materials.

  8. Computer vision for high content screening.

    Science.gov (United States)

    Kraus, Oren Z; Frey, Brendan J

    2016-01-01

    High Content Screening (HCS) technologies that combine automated fluorescence microscopy with high throughput biotechnology have become powerful systems for studying cell biology and drug screening. These systems can produce more than 100 000 images per day, making their success dependent on automated image analysis. In this review, we describe the steps involved in quantifying microscopy images and different approaches for each step. Typically, individual cells are segmented from the background using a segmentation algorithm. Each cell is then quantified by extracting numerical features, such as area and intensity measurements. As these feature representations are typically high dimensional (>500), modern machine learning algorithms are used to classify, cluster and visualize cells in HCS experiments. Machine learning algorithms that learn feature representations, in addition to the classification or clustering task, have recently advanced the state of the art on several benchmarking tasks in the computer vision community. These techniques have also recently been applied to HCS image analysis.

  9. Properties of cellulose micro/nanofibers obtained from eucalyptus pulp fiber treated with anaerobic digestate and high shear mixing

    Science.gov (United States)

    High production costs remain the single greatest factor limiting wider use of cellulose micro/nanofibers in the industry. The objective of the present study was to investigate the potential of using a low-cost bacteria-rich digestate (liquid anaerobic digestate – AD supernatant) on milled eucalyptus...

  10. Cellulose nanofibril/reduced graphene oxide/carbon nanotube hybrid aerogels for highly flexible and all-solid-state supercapacitors

    Science.gov (United States)

    Qifeng Zheng; Zhiyong Cai; Zhenqiang Ma; Shaoqin Gong

    2015-01-01

    A novel type of highly flexible and all-solid-state supercapacitor that uses cellulose nanofibril (CNF)/reduced graphene oxide (RGO)/carbon nanotube (CNT) hybrid aerogels as electrodes and H2SO4 poly (vinyl alcohol) PVA gel as the electrolyte was developed and is reported here. These flexible solid-state supercapacitors...

  11. Synthesis of cellulose-based superabsorbent hydrogels by high-energy irradiation in the presence of crosslinking agent

    Science.gov (United States)

    Fekete, Tamás; Borsa, Judit; Takács, Erzsébet; Wojnárovits, László

    2016-01-01

    Superabsorbent hydrogels were prepared from aqueous solutions of four cellulose derivatives (carboxymethylcellulose Na-salt - CMC, methylcellulose - MC, hydroxyethylcellulose - HEC and hydroxypropylcellulose - HPC) by gamma irradiation initiated crosslinking. CMC was used for the majority of the measurements. N,N'-methylene-bis-acrylamide (MBA) crosslinking agent was used to modify the gel properties. The crosslink density increased with the MBA concentration, leading to an improved gel fraction and lower water uptake. The crosslinking efficiency was the highest up to 1 w/wpolymer% MBA concentration. Very high MBA content (10 w/wpolymer%) led to a heterogeneous gel structure. Gelation also occurred under milder conditions in the presence of MBA: good gel properties were achieved at significantly lower doses and solute concentrations as compared to crosslinker-free solutions. The time required to reach maximum water uptake increased with the degree of swelling in equilibrium. Swelling properties of CMC gels with lower water uptake showed lower sensitivity to the ionic strength of the solvent.

  12. Study on novel functional materials carboxymethyl cellulose lithium (CMC-Li) improve high-performance lithium-ion battery.

    Science.gov (United States)

    Qiu, Lei; Shao, Ziqiang; Xiang, Pan; Wang, Daxiong; Zhou, Zhenwen; Wang, Feijun; Wang, Wenjun; Wang, Jianquan

    2014-09-22

    Novel cellulose derivative CMC-Li was synthesized by cotton as raw material. The mechanism of the CMC-Li modified electrode materials by electrospinning was reported. CMC-Li/lithium iron phosphate (LiFePO4, LFP) composite fiber coated with LFP and CMC-Li nanofibers was successfully obtained by electrospinning. Then, CMC-Li/LFP nano-composite fiber was carbonized under nitrogen at a high temperature formed CNF/LFP/Li (CLL) composite nanofibers as cathode material. It can increase the contents of Li+, and improving the diffusion efficiency and specific capacity. The battery with CLL as cathode material retained close to 100% of initial reversible capacity after 200 cycles at 168 mAh g(-1), which was nearly the theoretical specific capacity of LFP. The cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and scanning electron microscope (SEM) were characterizing material performance. The batteries have good electrochemical property, outstanding pollution-free, excellent stability. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Papillomavirus microbicidal activities of high-molecular-weight cellulose sulfate, dextran sulfate, and polystyrene sulfonate.

    Science.gov (United States)

    Christensen, N D; Reed, C A; Culp, T D; Hermonat, P L; Howett, M K; Anderson, R A; Zaneveld, L J

    2001-12-01

    The high-molecular-weight sulfated or sulfonated polysaccharides or polymers cellulose sulfate, dextran sulfate, and polystyrene sulfonate were tested for microbicidal activity against bovine papillomavirus type 1 (BPV-1) and human papillomavirus type 11 (HPV-11) and type 40 (HPV-40). In vitro assays included the BPV-1-induced focus-forming assay and transient infection of human A431 cells with HPVs. The compounds were tested for microbicidal activity directly by preincubation with virus prior to addition to cell cultures and indirectly by addition of virus to compound-treated cells and to virus-coated cells to test inactivation of the virus after virus-cell binding. The data indicated that all three compounds showed direct microbicidal activity with 50% effective concentrations between 10 to 100 microg/ml. These concentrations were nontoxic to cell cultures for both assays. When a clone of C127 cells was tested for microbicidal activity, approximately 10-fold-less compound was required to achieve a 50% reduction in BPV-1-induced foci than for the uncloned parental C127 cells. Pretreatment of cells with compound prior to addition of virus also demonstrated strong microbicidal activity with dextran sulfate and polystyrene sulfonate, but cellulose sulfate required several orders of magnitude more compound for virus inactivation. Polystyrene sulfonate prevented subsequent infection of HPV-11 after virus-cell binding, and this inactivation was observed up to 4 h after addition of virus. These data indicate that the polysulfated and polysulfonated compounds may be useful nontoxic microbicidal compounds that are active against a variety of sexually transmitted disease agents including papillomaviruses.

  14. Direct ethanol production from cellulosic materials at high temperature using the thermotolerant yeast Kluyveromyces marxianus displaying cellulolytic enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Yanase, Shuhei; Yamada, Ryosuke; Ogino, Chiaki; Kondo, Akihiko [Kobe Univ. (Japan). Dept. of Chemical Science and Engineering; Hasunuma, Tomohisa; Tanaka, Tsutomu; Fukuda, Hideki [Kobe Univ. (Japan). Organization of Advanced Science and Technology

    2010-09-15

    To exploit cellulosic materials for fuel ethanol production, a microorganism capable of high temperature and simultaneous saccharification-fermentation has been required. However, a major drawback is the optimum temperature for the saccharification and fermentation. Most ethanol-fermenting microbes have an optimum temperature for ethanol fermentation ranging between 28 C and 37 C, while the activity of cellulolytic enzymes is highest at around 50 C and significantly decreases with a decrease in temperature. Therefore, in the present study, a thermotolerant yeast, Kluyveromyces marxianus, which has high growth and fermentation at elevated temperatures, was used as a producer of ethanol from cellulose. The strain was genetically engineered to display Trichoderma reesei endoglucanase and Aspergillus aculeatus {beta}-glucosidase on the cell surface, which successfully converts a cellulosic {beta}-glucan to ethanol directly at 48 C with a yield of 4.24 g/l from 10 g/l within 12 h. The yield (in grams of ethanol produced per gram of {beta}-glucan consumed) was 0.47 g/g, which corresponds to 92.2% of the theoretical yield. This indicates that high-temperature cellulose fermentation to ethanol can be efficiently accomplished using a recombinant K. marxianus strain displaying thermostable cellulolytic enzymes on the cell surface. (orig.)

  15. Cellulose binding domain proteins

    Science.gov (United States)

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc; Doi, Roy

    1998-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  16. Electrospinning of silver nanoparticles loaded highly porous cellulose acetate nanofibrous membrane for treatment of dye wastewater

    Science.gov (United States)

    Wang, Ke; Ma, Qian; Wang, Shu-Dong; Liu, Hua; Zhang, Sheng-Zhong; Bao, Wei; Zhang, Ke-Qin; Ling, Liang-Zhong

    2016-01-01

    In this paper, silver nanoparticles (NPs) were reduced form silver nitrate. Morphology and distribution of the synthesized silver NPs were characterized. In order to obtain cellulose acetate (CA), nanofibrous membrane with high effective adsorption performance to carry silver NPs for treatment of dye wastewater, different solvent systems were used to fabricate CA nanofibrous membranes with different morphologies and porous structures via electrospinning. Morphologies and structures of the obtained CA nanofibrous membranes were compared by scanning electron microscopy (SEM), which showed that CA nanofibrous membrane obtained from acetone/dichloromethane (1/2, v/v) was with the highly porous structure. SEM, energy-dispersive spectrometry and Fourier transform infrared spectrometry showed that the silver NPs were effectively incorporated in the CA nanofibrous membrane and the addition of silver NPs did not damage the porous structure of the CA nanofibrous membrane. Adsorption of dye solution (rhodamine B aqueous solution) revealed that the highly porous CA nanofibrous membrane exhibited effective adsorption performance and the addition of silver NPs did not affect the adsorption of the dye. Antibacterial property of the CA nanofibrous membrane showed that the silver-loaded highly porous CA nanofibrous membrane had remarkable antibacterial property when compared to the CA nanofibrous membrane without silver NPs. The silver-loaded highly porous CA nanofibrous membrane could be considered as an ideal candidate for treatment of the dye wastewater.

  17. Cellulose functionalization via high-energy irradiation-initiated grafting of glycidyl methacrylate and cyclodextrin immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Desmet, Gilles [Institute of Isotopes, Hungarian Academy of Sciences, H-1525 Budapest, Pf. 77 (Hungary); Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, H-1521 Budapest, Pf. 91 (Hungary); Takacs, Erzsebet, E-mail: takacs@iki.kfki.hu [Institute of Isotopes, Hungarian Academy of Sciences, H-1525 Budapest, Pf. 77 (Hungary); Wojnarovits, Laszlo [Institute of Isotopes, Hungarian Academy of Sciences, H-1525 Budapest, Pf. 77 (Hungary); Borsa, Judit [Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, H-1521 Budapest, Pf. 91 (Hungary)

    2011-12-15

    Cotton-cellulose was functionalized using gamma-irradiation-induced grafting of glycidyl methacrylate (GMA) to obtain a hydrophobic cellulose derivative with epoxy groups suitable for further chemical modification. Two grafting techniques were applied. In pre-irradiation grafting (PIG) cellulose was irradiated in air and then immersed in a GMA monomer solution, whereas in simultaneous grafting (SG) cellulose was irradiated in an inert atmosphere in the presence of the monomer. PIG led to a more homogeneous fiber surface, while SG resulted in higher grafting yield but showed clear indications of some GMA-homopolymerization. Effects of the reaction parameters (grafting method, absorbed dose, monomer concentration, solvent composition) were evaluated by SEM, gravimetry (grafting yield) and FTIR spectroscopy. Water uptake of the cellulose decreased while adsorption of a pesticide molecule increased upon grafting. The adsorption was further enhanced by {beta}-cyclodextrin immobilization during SG. This method can be applied to produce adsorbents from cellulose based agricultural wastes. - Highlights: > Fundamentals of two grafting methods for biomass utilization as adsorbents. > Simultaneous grafting is more efficient and useful than the pre-irradiation one. > Methanol/water/surfactant combined solvent gives the best grafting yield. > Grafted cellulose increased hydrophobicity and adsorption of phenolic compounds. > Improved adsorption by bonding {beta}-cyclodextrin during simultaneous grafting.

  18. Ultralight, highly thermally insulating and fire resistant aerogel by encapsulating cellulose nanofibers with two-dimensional MoS2.

    Science.gov (United States)

    Yang, Lei; Mukhopadhyay, Alolika; Jiao, Yucong; Yong, Qiang; Chen, Liao; Xing, Yingjie; Hamel, Jonathan; Zhu, Hongli

    2017-08-17

    Thermally insulating materials, made from earth-abundant and sustainable resources, are highly desirable in the sustainable construction of energy efficient buildings. Cellulose from wood has long been recognized for these characteristics. However, cellulose can be a flammability hazard, and for construction this has been addressed via chemical treatment such as that with halogen and/or phosphorus, which leads to further environmental concerns. Fortunately, the structure of cellulose lends itself well to chemical modification, giving great potential to explore interaction with other compounds. Thus, in this study, cellulose nanofibers (CNFs) were nano-wrapped with ultrathin 1T phase molybdenum disulfide (MoS2) nanosheets via chemical crosslinking, to produce an aerogel. Thermal and combustion characterization revealed highly desirable properties (thermal conductivity k = 28.09 mW m(-1) K(-1), insulation R value = 5.2, limit oxygen index (LOI) = 34.7%, total heat release = 0.4 MJ m(-2)). Vertical burning tests also demonstrated excellent fire retardant and self-extinguishing capabilities. Raman spectra further revealed that MoS2 remained unscathed after 30 seconds of burning in a 1300 °C butane flame. Considering the inherently low density of this material, there is significant opportunity for its usage in a number of insulating applications demanding specific fire resistance properties.

  19. Isolation and characterization of cellulose nanofibers from culinary banana peel using high-intensity ultrasonication combined with chemical treatment.

    Science.gov (United States)

    Khawas, Prerna; Deka, Sankar C

    2016-02-10

    In the present study, culinary banana peel was explored as a source of raw material for production of cellulose nanofibers (CNFs). For isolation of CNFs, first the peel flour was subjected to different chemical treatments to eliminate non-cellulosic compounds. The obtained chemically treated cellulose fibers were then mechanically tailored and separated into nanofibers using high-intensity ultrasonication at different output power ranging from 0 to 1000 W. The presences of nanofibers in all samples were confirmed by TEM. Increasing output power of ultrasonication reduced size of CNFs and generated more thinner and needle-like structure. SEM, FT-IR and XRD results indicated chemical treatment employed was effective in removing compounds other than cellulose fibers. Thermal analyses evinced the developed CNFs enhanced thermal properties which serve the purpose as an effective reinforcing material to be used as bionanocomposites. Hence, the production of CNFs from this underutilized agro-waste has potential application in commercial field that can add high value to culinary banana.

  20. High content screening in microfluidic devices

    Science.gov (United States)

    Cheong, Raymond; Paliwal, Saurabh; Levchenko, Andre

    2011-01-01

    Importance of the field Miniaturization is key to advancing the state-of-the-art in high content screening (HCS), in order to enable dramatic cost savings through reduced usage of expensive biochemical reagents and to enable large-scale screening on primary cells. Microfluidic technology offers the potential to enable HCS to be performed with an unprecedented degree of miniaturization. Areas covered in this review This perspective highlights a real-world example from the authors’ work of HCS assays implemented in a highly miniaturized microfluidic format. Advantages of this technology are discussed, including cost savings, high throughput screening on primary cells, improved accuracy, the ability to study complex time-varying stimuli, and ease of automation, integration, and scaling. What the reader will gain The reader will understand the capabilities of a new microfluidics-based platform for HCS, and the advantages it provides over conventional plate-based HCS. Take home message Microfluidics technology will drive significant advancements and broader usage and applicability of HCS in drug discovery. PMID:21852997

  1. Structure and Property of Silk Fibroin / Cellulose Blend Film

    Institute of Scientific and Technical Information of China (English)

    CHEN Guo-qiang; XING Tie-ling

    2004-01-01

    Silk fibroin/cellulose blend films were prepared using N-methylmorpholine -N-oxide (NMMO) as solvent. The effects of different proportions and solid contents on properties of blend films were discussed. The mechanical properties showed that the blend films had preferable moisture permeability and a high strength. The structures of the blend films were investigated by infrared spectrum and X-ray diffraction. The results indicated the occurrence of hydrogen bonds between hydroxyl groups of cellulose and amido groups of fibroin.

  2. Highly Modified Cellulose Nanocrystals and Formation of Epoxy-CNC Nanocomposites.

    Science.gov (United States)

    Abraham, Eldho; Kam, Doron; Nevo, Yuval; Slattegard, Rikard; Rivkin, Amit; Lapidot, Shaul; Shoseyov, Oded

    2016-10-05

    This work presents an environmentally friendly, iodine-catalysed chemical modification method to generate highly hydrophobic, optically active cellulose nanocrystals (CNC). The high degree of ester substitution (DS=2.18), hydrophobicity, crystalline behaviour and optical activity of the generated acetylated CNC (Ac-CNC) were quantified by TEM, FTIR, solid 13C NMR, contact angle, XRD and POM analyses. Ac-CNC possessing substantial enhancement in thermal stability (16.8%) and forms thin films with interlayer distance of 50-150 nm, presenting cavities suitable for entrapping nano and micro particles. Generated Ac-CNC proved as an effective reinforcing agent in hydrophobic polymer matrices for fabricating high performance nanocomposites. When integrated at a very low weight percentage (0.5%) in an epoxy matrix, Ac-CNC provided for a 73% increase in tensile strength and a 98% increase in modulus, demonstrating its remarkable reinforcing potential and effective stress transfer behaviour. The method of modification and the unique properties of the modified CNC (hydrophobicity, crystallinity, reinforcing ability and optical activity) render them a novel bionanomaterial for a range of multipurpose applications.

  3. Nanocomposites of TiO₂/cyanoethylated cellulose with ultra high dielectric constants.

    Science.gov (United States)

    Madusanka, Nadeesh; Shivareddy, Sai G; Hiralal, Pritesh; Eddleston, Mark D; Choi, Youngjin; Oliver, Rachel A; Amaratunga, Gehan A J

    2016-05-13

    A novel dielectric nanocomposite containing a high permittivity polymer, cyanoethylated cellulose (CRS) and TiO2 nanoparticles was successfully prepared with different weight percentages (10%, 20% and 30%) of TiO2. The intermolecular interactions and morphology within the polymer nanocomposites were analysed. TiO2/CRS nanofilms on SiO2/Si wafers were used to form metal-insulator-metal type capacitors. Capacitances and loss factors in the frequency range of 1 kHz-1 MHz were measured. At 1 kHz CRS-TiO2 nanocomposites exhibited ultra high dielectric constants of 118, 176 and 207 for nanocomposites with 10%, 20% and 30% weight of TiO2 respectively, significantly higher than reported values of pure CRS (21), TiO2 (41) and other dielectric polymer-TiO2 nanocomposite films. Furthermore, all three CRS-TiO2 nanocomposites show a loss factor dielectric constant hybrids using nanoscale inorganic dielectrics dispersed in a high permittivity polymer suitable for energy management applications is reported.

  4. Nanocomposites of TiO2/cyanoethylated cellulose with ultra high dielectric constants

    Science.gov (United States)

    Madusanka, Nadeesh; Shivareddy, Sai G.; Hiralal, Pritesh; Eddleston, Mark D.; Choi, Youngjin; Oliver, Rachel A.; Amaratunga, Gehan A. J.

    2016-05-01

    A novel dielectric nanocomposite containing a high permittivity polymer, cyanoethylated cellulose (CRS) and TiO2 nanoparticles was successfully prepared with different weight percentages (10%, 20% and 30%) of TiO2. The intermolecular interactions and morphology within the polymer nanocomposites were analysed. TiO2/CRS nanofilms on SiO2/Si wafers were used to form metal-insulator-metal type capacitors. Capacitances and loss factors in the frequency range of 1 kHz-1 MHz were measured. At 1 kHz CRS-TiO2 nanocomposites exhibited ultra high dielectric constants of 118, 176 and 207 for nanocomposites with 10%, 20% and 30% weight of TiO2 respectively, significantly higher than reported values of pure CRS (21), TiO2 (41) and other dielectric polymer-TiO2 nanocomposite films. Furthermore, all three CRS-TiO2 nanocomposites show a loss factor dielectric constant hybrids using nanoscale inorganic dielectrics dispersed in a high permittivity polymer suitable for energy management applications is reported.

  5. High-rate two-phase process for the anaerobic degradation of cellulose, employing rumen microorganisms for an efficient acidogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Gijzen, H.J.; Zwart, K.B.; Verhagen, F.J.M.; Vogels, G.D.

    1988-04-05

    A novel two-stage anaerobic process for the microbial conversion of cellulose into biogas has been developed. In the first phase, a mixed population of rumen bacteria and ciliates was used in the hydrolysis and fermentation of cellulose. The volatile fatty acids (VFA) produced in this acidogenic reactor were subsequently converted into biogas in a UASB-type methanogenic reactor. A stepwise increase of the loading rate from 11.9 to 25.8 g volatile solids/L reactor volume/day (g VS/L/day) did not affect the degradation efficiency in the acidogenic reactor, whereas the methanogenic reactor appeared to be overloaded at the highest loading rate. Cellulose digestion was almost complete at all loading rates applied. The two-stage anaerobic process was also tested with a closed fluid circuit. In this instance total methane production was 0.438 L CH/sub 4//g VS added, which is equivalent to 98% of the theoretical value. The application of rumen microorganisms in combination with a high-rate methane reactor is proposed as a means of efficient anaerobic degradation of cellulosic residues to methane. Because this newly developed two-phase system is based on processes and microorganisms from the ruminant, it will be referred to as Rumen Derived Anaerobic Digestion (RUDAD)-process.

  6. Comparative analysis of cellulose acetate hemoglobin electrophoresis and high performance liquid chromatography for quantitative determination of hemoglobin A2

    Science.gov (United States)

    Khosa, Shafi Mohammad; Moinuddin, Moinuddin; Mehmood, Hassan Osman; Qamar, Khansa

    2015-01-01

    Background The present study is designed to evaluate the reliability and cost effectiveness of cellulose acetate Hb electrophoresis and high performance liquid chromatography (HPLC) in the determination of HbA2 levels. Methods The test population comprised 160 individuals divided into four groups: normal individuals, β-thalassemia trait (BTT) patients, iron deficiency anemia (IDA) patients, and co-morbid patients (BTT with IDA). HbA2 levels determined using cellulose acetate Hb electrophoresis and HPLC were compared. Results HbA2 levels were found to be diagnostic for classical BTT using either method. In co-morbid cases, both techniques failed to diagnose all cases of BTT. The sensitivity, specificity, and Youden's index for detection of the co-morbid condition was 69% and 66% for HPLC and cellulose acetate Hb electrophoresis, respectively. Conclusion This study revealed that semi-automated cellulose acetate Hb electrophoresis is more suitable for use in β-thalassemia prevention programs in low-income countries like Pakistan. This technique is easily available, simple and cost effective. PMID:25830130

  7. Cellulose nanocrystals in nanocomposite approach: Green and high-performance materials for industrial, biomedical and agricultural applications

    Science.gov (United States)

    Fortunati, E.; Torre, L.

    2016-05-01

    The need to both avoid wastes and find new renewable resources has led to a new and promising research based on the possibility to revalorize the biomass producing sustainable chemicals and/or materials which may play a major role in replacing systems traditionally obtained from non-renewable sources. Most of the low-value biomass is termed lignocellulosic, referring to its main constituent biopolymers: cellulose, hemicelluloses and lignin. In this context, nanocellulose, and in particular cellulose nanocrystals (CNC), have gain considerable attention as nanoreinforcement for polymer matrices, mainly biodegradable. Derived from the most abundant polymeric resource in nature and with inherent biodegradability, nanocellulose is an interesting nanofiller for the development of nanocomposites for industrial, biomedical and agricultural applications. Due to the high amount of hydroxyl groups on their surface, cellulose nanocrystals are easy to functionalize. Well dispersed CNC are able, in fact, to enhance several properties of polymers, i.e.: thermal, mechanical, barrier, surface wettability, controlled of active compound and/or drug release. The main objective here is to give a general overview of CNC applications, summarizing our recent developments of bio-based nanocomposite formulations reinforced with cellulose nanocrystals extracted from different natural sources and/or wastes for food packaging, medical and agricultural sectors.

  8. Hierarchical-structured anatase-titania/cellulose composite sheet with high photocatalytic performance and antibacterial activity.

    Science.gov (United States)

    Luo, Yan; Huang, Jianguo

    2015-02-02

    Bulk hierarchical anatase-titania/cellulose composite sheets were fabricated by subjecting an ultrathin titania gel film pre-deposited filter paper to a solvo-co-hydrothermal treatment by using titanium butoxide as the precursor to grow anatase-titania nanocrystallites on the cellulose nanofiber surfaces. The titanium butoxide specie is firstly absorbed onto the nanofibers of the cellulose substance through a solvothermal process, which was thereafter hydrolyzed and crystallized upon the subsequent hydrothermal treatment, leading to the formation of fine anatase-titania nanoparticles with sizes of 2-5 nm uniformly anchored on the cellulose nanofibers. The resulting anatase-titania/cellulose composite sheet shows a significant photocatalytic performance towards degradation of a methylene blue dye, and introduction of silver nanoparticles into the composite sheet yields an Ag-NP/anatase-titania/cellulose composite material possessing excellent antibacterial activity against both Gram-positive and Gram-negative bacteria. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Taichi-inspired rigid-flexible coupling cellulose-supported solid polymer electrolyte for high-performance lithium batteries

    OpenAIRE

    Zhang, Jianjun; Yue, Liping; Hu, Pu; Liu, Zhihong; Qin, Bingsheng; Zhang, Bo; Wang, Qingfu; DING, GUOLIANG; Zhang, Chuanjian; Zhou, Xinhong; Yao, Jianhua; Cui, Guanglei; Chen, Liquan

    2014-01-01

    Inspired by Taichi, we proposed rigid-flexible coupling concept and herein developed a highly promising solid polymer electrolyte comprised of poly (ethylene oxide), poly (cyano acrylate), lithium bis(oxalate)borate and robust cellulose nonwoven. Our investigation revealed that this new class solid polymer electrolyte possessed comprehensive properties in high mechanical integrity strength, sufficient ionic conductivity (3 × 10−4 S cm−1) at 60°C and improved dimensional thermostability (up to...

  10. Simulation of variations in the composition of samples in the evaluation of neutral detergent fiber contents by using cellulose standard in filter bags made from different textiles

    Directory of Open Access Journals (Sweden)

    Tiago Neves Pereira Valente

    2011-07-01

    Full Text Available The objective of this study was to evaluate the efficiency of using nylon textiles (50 μm, F57 (Ankom® and non-woven textile (NWT - 100 g/m² on laboratory evaluation of neutral detergent fiber (NDF by using quantitative filter paper as purified cellulose standard and by simulating different composition of samples with additions of corn starch, pectin, casein and soybean oil. The quantitative filter paper was processed in a knife mill with a 1-mm screen sieve and the procedures for analyses of NDF contents were performed in a fiber analyzer (Ankom220®. Four experiments were carried out with additions of different ingredients into the filter paper: corn starch added at the levels of 15 or 50%; pectin, 15 or 50%; casein, 10 or 30%; and soybean oil at 0, 5, 10, 15, 25 or 50% of dry matter, respectively. The ratio 20 mg of dry matter/cm² of surface was followed. When it was relevant, in function of the evaluated treatments, heat-stable α-amylase was used. The use of F57 and NWT resulted in accurate estimates of NDF contents whereas nylon textile caused loss of insoluble fibrous particles, compromising accuracy of the results. For samples containing starch, use of heat-stable α-amylase is recommended in the evaluation of NDF contents. Pectin and casein are completely solubilized by neutral detergent solution. Levels of oil higher than 10% cause overestimation of NDF contents.

  11. Quantitative Immobilization of Phthalocyanine onto Bacterial Cellulose for Construction of a High-Performance Catalytic Membrane Reactor.

    Science.gov (United States)

    Chen, Shiliang; Teng, Qiaoling

    2017-07-24

    We report the fabrication of a tetra-amino cobalt (II) phthalocyanine (CoPc)-immobilized bacterial cellulose (BC) functional nanocomposite, CoPc@BC, by quantitative immobilization of CoPc onto a BC membrane. Lab-cultured BC was oxidized by NaIO₄ to generate aldehyde groups on BC for the subsequent CoPc immobilization, the processing conditions were optimized by monitoring both the generated aldehyde content and the resulting CoPc loading. X-ray photoelectron spectroscopy (XPS) was employed to characterize the change of the element bonding environment during the functionalization processes. The CoPc@BC functional nanocomposite was utilized for the treatment of reactive red X-3B dye wastewater. The CoPc molecules in the CoPc@BC nanocomposite can function as an "antenna" to adsorb the target anionic dye molecules, the adsorption takes place both on the surface and in the interior of CoPc@BC. A catalytic membrane reactor (CMR) was assembled with the CoPc@BC nanocomposite, the performance of CMR was evaluated based on the catalytic oxidation behavior of reactive red X-3B, with H₂O₂ as an oxidant. Highly-reactive hydroxyl radical (OH) was involved in the catalytic oxidation process, as detected by electron paramagnetic resonance (EPR). Under optimal operating conditions of a flow rate of 6 mL/min, a reaction temperature of 50 °C, and an H₂O₂ concentration of 10 mmol/L, the decoloration rate of CMR was as high as 50 μmol⋅min(-1)⋅g(-1).

  12. Novel cellulose ester substrates for high performance flat-sheet thin-film composite (TFC) forward osmosis (FO) membranes

    KAUST Repository

    Ong, Rui Chin

    2015-01-01

    A novel hydrophilic cellulose ester with a high intrinsic water permeability and a water partition coefficient was discovered to construct membrane supports for flat-sheet thin film composite (TFC) forward osmosis (FO) membranes for water reuse and seawater desalination with high performance. The performance of TFC-FO membranes prepared from the hydrophilic cellulose ester containing a high degree of OH and a moderate degree of Pr substitutions clearly surpasses those prepared from cellulose esters and other polymers with moderate hydrophilicity. Post-treatments of TFC-FO membranes using sodium dodecyl sulfate (SDS) and glycerol followed by heat treatment further enhance the water flux without compromising the selectivity. Positron annihilation lifetime analyses have confirmed that the SDS/glycerol post-treatment increases the free volume size and fractional free volume of the polyamide selective layer. The newly developed post-treated TFC-FO membranes exhibit a remarkably high water flux up to 90 LMH when the selective layer is oriented towards the draw solution (i.e., PRO mode) using 1. M NaCl as the draw solution and DI water as the feed. For seawater desalination, the membranes display a high water flux up to 35 LMH using a 2. M NaCl draw solution. These water fluxes exceeded the water fluxes achieved by other types of FO membranes reported in literatures. © 2014 Elsevier B.V.

  13. Freestanding bacterial cellulose-graphene oxide composite membranes with high mechanical strength for selective ion permeation

    Science.gov (United States)

    Fang, Qile; Zhou, Xufeng; Deng, Wei; Zheng, Zhi; Liu, Zhaoping

    2016-09-01

    Graphene oxide (GO) based membranes have been widely applied in molecular separation based on the size exclusion effect of the nanochannels formed by stacked GO sheets. However, it’s still a challenge to prepare a freestanding GO-based membrane with high mechanical strength and structural stability which is prerequisite for separation application in aqueous solution. Here, a freestanding composite membrane based on bacterial cellulose (BC) and GO is designed and prepared. BC network provides a porous skeleton to spread GO sheets and uniformly incorporates into the GO layers, which endows the BC + GO composite membrane with well water-stability, excellent tensile strength, as well as improved toughness, guaranteeing its separation applicability in water environment. The resulting BC + GO membrane exhibits obviously discrepant permeation properties for different inorganic/organic ions with different size, and in particular, it can quickly separate ions in nano-scale from angstrom-scale. Therefore, this novel composite membrane is considered to be a promising candidate in the applications of water purification, food industry, biomedicine, and pharmaceutical and fuel separation.

  14. Super-Hydrophobic High Throughput Electrospun Cellulose Acetate (CA) Nanofibrous Mats as Oil Selective Sorbents

    Science.gov (United States)

    Han, Chao

    The threat of oil pollution increases with the expansion of oil exploration and production activities, as well as the industrial growth around the world. Use of sorbents is a common method to deal with the oil spills. In this work, an advanced sorbent technology is described. A series of non-woven Cellulose Acetate (CA) nanofibrous mats with a 3D fibrous structure were synthesized by a novel high-throughput electrospinning technique. The precursor was solutions of CA/ acetic acid-acetone in various concentrations. Among them, 15.0% CA exhibits a superhydrophobic surface property, with a water contact angle of 128.95°. Its oil sorption capacity is many times higher the oil sorption capacity of the best commercial sorbent available in the market. Also, it showed good buoyancy properties on the water both as dry-mat and oil-saturated mat. In addition, it is biodegradable, easily available, easily manufactured, so the CA nanofibrous mat is an excellent candidate as oil sorbent for oil spill in water treatment.

  15. Freestanding bacterial cellulose-graphene oxide composite membranes with high mechanical strength for selective ion permeation

    Science.gov (United States)

    Fang, Qile; Zhou, Xufeng; Deng, Wei; Zheng, Zhi; Liu, Zhaoping

    2016-01-01

    Graphene oxide (GO) based membranes have been widely applied in molecular separation based on the size exclusion effect of the nanochannels formed by stacked GO sheets. However, it’s still a challenge to prepare a freestanding GO-based membrane with high mechanical strength and structural stability which is prerequisite for separation application in aqueous solution. Here, a freestanding composite membrane based on bacterial cellulose (BC) and GO is designed and prepared. BC network provides a porous skeleton to spread GO sheets and uniformly incorporates into the GO layers, which endows the BC + GO composite membrane with well water-stability, excellent tensile strength, as well as improved toughness, guaranteeing its separation applicability in water environment. The resulting BC + GO membrane exhibits obviously discrepant permeation properties for different inorganic/organic ions with different size, and in particular, it can quickly separate ions in nano-scale from angstrom-scale. Therefore, this novel composite membrane is considered to be a promising candidate in the applications of water purification, food industry, biomedicine, and pharmaceutical and fuel separation. PMID:27615451

  16. An adsorbent with a high adsorption capacity obtained from the cellulose sludge of industrial residues.

    Science.gov (United States)

    Orlandi, Géssica; Cavasotto, Jéssica; Machado, Francisco R S; Colpani, Gustavo L; Magro, Jacir Dal; Dalcanton, Francieli; Mello, Josiane M M; Fiori, Márcio A

    2017-02-01

    One of the major problems in effluent treatment plants of the cellulose and paper industry is the large amount of residual sludge generated. Therefore, this industry is trying to develop new methods to treat such residues and to use them as new products, such as adsorbents. In this regard, the objective of this work was to develop an adsorbent using the raw activated sludge generated by the cellulose and paper industry. The activated cellulose sludge, after being dried, was chemically activated with 42.5% (v/v) phosphoric acid at 85 °C for 1 h and was charred at 500 °C, 600 °C and 700 °C for 2 h. The efficiency of the obtained adsorbent materials was evaluated using kinetic tests with methylene blue solutions. Using the adsorption kinetics, it was verified that the three adsorbents showed the capacity to adsorb dye, and the adsorbent obtained at a temperature of 600 °C showed the highest adsorption capacity of 107.1 mg g(-1). The kinetic model that best fit the experimental data was pseudo-second order. The Langmuir-Freudlich isotherm adequately described the experimental data. As a result, the cellulose sludge generated by the cellulose and paper industries could be used as an adsorbent.

  17. High content analysis in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Rinaldi, Federica; Motti, Dario; Ferraiuolo, Laura; Kaspar, Brian K

    2017-04-01

    Amyotrophic lateral sclerosis (ALS) is a devastating disease characterized by the progressive loss of motor neurons. Neurons, astrocytes, oligodendrocytes and microglial cells all undergo pathological modifications in the onset and progression of ALS. A number of genes involved in the etiopathology of the disease have been identified, but a complete understanding of the molecular mechanisms of ALS has yet to be determined. Currently, people affected by ALS have a life expectancy of only two to five years from diagnosis. The search for a treatment has been slow and mostly unsuccessful, leaving patients in desperate need of better therapies. Until recently, most pre-clinical studies utilized the available ALS animal models. In the past years, the development of new protocols for isolation of patient cells and differentiation into relevant cell types has provided new tools to model ALS, potentially more relevant to the disease itself as they directly come from patients. The use of stem cells is showing promise to facilitate ALS research by expanding our understanding of the disease and help to identify potential new therapeutic targets and therapies to help patients. Advancements in high content analysis (HCA) have the power to contribute to move ALS research forward by combining automated image acquisition along with digital image analysis. With modern HCA machines it is possible, in a period of just a few hours, to observe changes in morphology and survival of cells, under the stimulation of hundreds, if not thousands of drugs and compounds. In this article, we will summarize the major molecular and cellular hallmarks of ALS, describe the advancements provided by the in vitro models developed in the last few years, and review the studies that have applied HCA to the ALS field to date. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. [Quality by design based high shear wet granulation process development for the microcrystalline cellulose].

    Science.gov (United States)

    Luo, Gan; Xu, Bing; Sun, Fei; Cui, Xiang-long; Shi, Xin-yuan; Qiao, Yan-jiang

    2015-03-01

    The design space of the high shear wet granulation process was established and validated within the framework of quality by design (QbD). The system of microcrystalline cellulose-de-ioned water was used in this study. The median granule size and bulk density of granules were identified as critical quality attributes. Plackeet-Burmann experimental design was used to screen these factors as follows: dry mixing time, the impeller and chopper speed of dry mixing, water amount, water addition time, wet massing time, the impeller and chopper speed of wet massing and drying time. And the optimization was implemented with the central composite experimental design based on screened critical process parameters. The design space of the high shear wet granulation process was established based on the quadratic polynomial regression model. Since the P-values of both models were less than 0.05 and values of lack of fit were more than 0.1, the relationship between critical quality attributes and critical process parameters could be well described by the two models. The reliability of design space, illustrated by overlay plot, was improved with the addition of 95% confidence interval. For those granules whose process parameters were in the design space, the granule size could be controlled within 250 to 355 μm, and the bulk density could be controlled within a range of 0.4 to 0.6 g x cm(-3). The robustness and flexibility of the high shear wet granulation process have been enhanced via the establishment of the design space based on the QbD concept.

  19. CHARACTERIZATION OF REGENERATED CELLULOSE MEMBRANES HYDROLYZED FROM CELLULOSE ACETATE

    Institute of Scientific and Technical Information of China (English)

    Yun Chen; Xiao-peng Xiong; Guang Yang; Li-na Zhang; Sen-lin Lei; Hui Lianga

    2002-01-01

    A series of cellulose acetate membranes were prepared by using formamide as additive, and then were hydrolyzedin 4 wt% aqueous NaOH solution for 8 h to obtain regenerated cellulose membranes. The dependence of degree ofsubstitution, structure, porous properties, solubility and thermal stability on hydrolysis time was studied by chemical titration,Fourier transform infrared spectroscopy, scanning electron microscopy, wide-angle X-ray diffraction, and differentialscanning calorimetry, respectively. The results indicated that the pore size of the regenerated cellulose membranes wasslightly smaller than that of cellulose acetate membrane, while solvent-resistance, crystallinity and thermostability weresignificantly improved. This work provides a simple way to prepare the porous cellulose membranes, which not only kept thegood pore characteristics of cellulose acetate membranes, but also possessed solvent-resistance, high crystallinity andthermostability. Therefore, the application range of cellulose acetate membranes can be expanded.

  20. Hazy Transparent Cellulose Nanopaper

    Science.gov (United States)

    Hsieh, Ming-Chun; Koga, Hirotaka; Suganuma, Katsuaki; Nogi, Masaya

    2017-01-01

    The aim of this study is to clarify light scattering mechanism of hazy transparent cellulose nanopaper. Clear optical transparent nanopaper consists of 3–15 nm wide cellulose nanofibers, which are obtained by the full nanofibrillation of pulp fibers. At the clear transparent nanopaper with 40 μm thickness, their total transmittance are 89.3–91.5% and haze values are 4.9–11.7%. When the pulp fibers are subjected to weak nanofibrillation, hazy transparent nanopapers are obtained. The hazy transparent nanopaper consists of cellulose nanofibers and some microsized cellulose fibers. At the hazy transparent nanopaper with 40 μm thickness, their total transmittance were constant at 88.6–92.1% but their haze value were 27.3–86.7%. Cellulose nanofibers are solid cylinders, whereas the pulp fibers are hollow cylinders. The hollow shape is retained in the microsized cellulose fibers, but they are compressed flat inside the nanopaper. This compressed cavity causes light scattering by the refractive index difference between air and cellulose. As a result, the nanopaper shows a hazy transparent appearance and exhibits a high thermal durability (295–305 °C), and low thermal expansion (8.5–10.6 ppm/K) because of their high density (1.29–1.55 g/cm3) and crystallinity (73–80%).

  1. Effects of alkaline or liquid-ammonia treatment on crystalline cellulose: changes in crystalline structure and effects on enzymatic digestibility

    Directory of Open Access Journals (Sweden)

    Himmel Michael E

    2011-10-01

    Full Text Available Abstract Background In converting biomass to bioethanol, pretreatment is a key step intended to render cellulose more amenable and accessible to cellulase enzymes and thus increase glucose yields. In this study, four cellulose samples with different degrees of polymerization and crystallinity indexes were subjected to aqueous sodium hydroxide and anhydrous liquid ammonia treatments. The effects of the treatments on cellulose crystalline structure were studied, in addition to the effects on the digestibility of the celluloses by a cellulase complex. Results From X-ray diffractograms and nuclear magnetic resonance spectra, it was revealed that treatment with liquid ammonia produced the cellulose IIII allomorph; however, crystallinity depended on treatment conditions. Treatment at a low temperature (25°C resulted in a less crystalline product, whereas treatment at elevated temperatures (130°C or 140°C gave a more crystalline product. Treatment of cellulose I with aqueous sodium hydroxide (16.5 percent by weight resulted in formation of cellulose II, but also produced a much less crystalline cellulose. The relative digestibilities of the different cellulose allomorphs were tested by exposing the treated and untreated cellulose samples to a commercial enzyme mixture (Genencor-Danisco; GC 220. The digestibility results showed that the starting cellulose I samples were the least digestible (except for corn stover cellulose, which had a high amorphous content. Treatment with sodium hydroxide produced the most digestible cellulose, followed by treatment with liquid ammonia at a low temperature. Factor analysis indicated that initial rates of digestion (up to 24 hours were most strongly correlated with amorphous content. Correlation of allomorph type with digestibility was weak, but was strongest with cellulose conversion at later times. The cellulose IIII samples produced at higher temperatures had comparable crystallinities to the initial cellulose I

  2. Hydrological responses of land use change from cotton (Gossypium hirsutum L.) to cellulosic bioenergy crops in the Southern High Plains of Texas, USA

    National Research Council Canada - National Science Library

    Chen, Yong; Ale, Srinivasulu; Rajan, Nithya; Morgan, Cristine L. S; Park, Jongyoon

    2016-01-01

    The Southern High Plains ( SHP ) region of Texas in the United States, where cotton is grown in a vast acreage, has the potential to grow cellulosic bioenergy crops such as perennial grasses and biomass sorghum ( Sorghum bicolor...

  3. Densification-induced conductivity percolation in high-porosity pharmaceutical microcrystalline cellulose compacts

    Science.gov (United States)

    Strømme, M.; Niklasson, G. A.; Ek, R.

    2003-01-01

    The percolation theory is established as a useful tool in the field of pharmaceutical materials science. It is shown that percolation theory, developed for analyzing insulator-conductor transitions, can be applied to describe imperfect dc conduction in pharmaceutical microcrystalline cellulose during densification. The system, in fact, exactly reproduces the values of the percolation threshold and exponent estimated for a three-dimensional random continuum. Our data clearly show a crossover from a power-law percolation theory region to a linear effective medium theory region at a cellulose porosity of ˜0.7.

  4. Cellulose Microfibril Formation by Surface-Tethered Cellulose Synthase Enzymes.

    Science.gov (United States)

    Basu, Snehasish; Omadjela, Okako; Gaddes, David; Tadigadapa, Srinivas; Zimmer, Jochen; Catchmark, Jeffrey M

    2016-02-23

    Cellulose microfibrils are pseudocrystalline arrays of cellulose chains that are synthesized by cellulose synthases. The enzymes are organized into large membrane-embedded complexes in which each enzyme likely synthesizes and secretes a β-(1→4) glucan. The relationship between the organization of the enzymes in these complexes and cellulose crystallization has not been explored. To better understand this relationship, we used atomic force microscopy to visualize cellulose microfibril formation from nickel-film-immobilized bacterial cellulose synthase enzymes (BcsA-Bs), which in standard solution only form amorphous cellulose from monomeric BcsA-B complexes. Fourier transform infrared spectroscopy and X-ray diffraction techniques show that surface-tethered BcsA-Bs synthesize highly crystalline cellulose II in the presence of UDP-Glc, the allosteric activator cyclic-di-GMP, as well as magnesium. The cellulose II cross section/diameter and the crystal size and crystallinity depend on the surface density of tethered enzymes as well as the overall concentration of substrates. Our results provide the correlation between cellulose microfibril formation and the spatial organization of cellulose synthases.

  5. Selective oxidation of lignocellulosic biomass to formic acid and high-grade cellulose using tailor-made polyoxometalate catalysts.

    Science.gov (United States)

    Albert, Jakob

    2017-06-27

    The main goal of this project was to identify and optimize tailor-made polyoxometalate catalysts for a fractionated oxidation of lignocellulosic biomass (i.e. wood and residues from sugar or paper industries) to produce formic acid (FA) and high-grade cellulose for further processing e.g. in white biotechnology to provide bio-ethanol. Homogeneous vanadium precursors like sodium metavanadate and vanadyl sulfate as well as Keggin-type polyoxometalates (POMs) and more exotic structures like Anderson-, Wells-Dawson- and Lindqvist-type POMs were screened for the desired catalytic performance. The most promising behaviour was found using the Lindqvist-type POM K5V3W3O19, showing for the first time in the literature a selective oxidation of only hemicellulose and lignin to formic acid, while the cellulose fraction was untrapped. However, this can only be a first step towards the project goal as low product yields were obtained.

  6. USE OF ALUMINUM TRIHYDRATE FILLER TO IMPROVE THE STRENGTH PROPERTIES OF CELLULOSIC PAPER EXPOSED TO HIGH TEMPERATURE TREATMENT

    Directory of Open Access Journals (Sweden)

    Hua Chen

    2011-05-01

    Full Text Available Cellulosic paper is thermolabile and its strength properties tend to decrease under high temperature conditions. In this work, the effects of aluminum trihydrate filler on the tensile and burst strength of paper prepared from bleached wood pulps were investigated. The use of aluminum trihydrate maintained the tensile and burst strength of paper sheet dried at 200 °C for 4 hours. Thermogravimetric analysis and differential scanning calorimetry gave the evidence that the maintainance of strength after drying associated with the use of aluminum trihydrate filler is possibly due to the increase in degradation temperature and heat absorption of cellulosic paper. The results regarding Fourier Transform Infrared spectroscopy, and the water retention value (WRV and crystallinity index of fibers indicated the alleviated degradation of fibers when aluminum trihydrate was incorporated into the paper matrix.

  7. Cellulose Nanofibril Based-Aerogel Microreactors: A High Efficiency and Easy Recoverable W/O/W Membrane Separation System

    Science.gov (United States)

    Zhang, Fang; Ren, Hao; Dou, Jing; Tong, Guolin; Deng, Yulin

    2017-01-01

    Hereby we report a novel cellulose nanofirbril aerogel-based W/O/W microreactor system that can be used for fast and high efficient molecule or ions extraction and separation. The ultra-light cellulose nanofibril based aerogel microspheres with high porous structure and water storage capacity were prepared. The aerogel microspheres that were saturated with stripping solution were dispersed in an oil phase to form a stable water-in-oil (W/O) suspension. This suspension was then dispersed in large amount of external waste water to form W/O/W microreactor system. Similar to a conventional emulsion liquid membrane (ELM), the molecules or ions in external water can quickly transport to the internal water phase. However, the microreactor is also significantly different from traditional ELM: the water saturated nanocellulose cellulose aerogel microspheres can be easily removed by filtration or centrifugation after extraction reaction. The condensed materials in the filtrated aerogel particles can be squeezed and washed out and aerogel microspheres can be reused. This novel process overcomes the key barrier step of demulsification in traditional ELM process. Our experimental indicates the novel microreactor was able to extract 93% phenol and 82% Cu2+ from external water phase in a few minutes, suggesting its great potential for industrial applications.

  8. Highly porous, ultra-low refractive index coatings produced throughrandom packing of silicated cellulose nanocrystals

    NARCIS (Netherlands)

    Buskens, P.J.P.; Mourada, M.; Meulendijks, N.M.M.; Ee, R.J. van; Burghoorn, M.M.A.; Verheijen, M.; Veldhoven, E. van

    2015-01-01

    The use of cellulose nanocrystals (CNCs) in optical materials has been extensively studied. Key in mostapplications reported to date is the chiral nematic ordering of CNCs. Here, we demonstrate that randompacking of silicated CNCs can also yield materials with interesting optical properties, i.e., h

  9. Influence of high loading of cellulose nanocrystals in polyacrylonitrile composite films

    Science.gov (United States)

    Jeffrey Luo; Huibin Chang; Amir A. Bakhtiary Davijani; H. Clive Liu; Po-Hsiang Wang; Robert J. Moon; Satish Kumar

    2017-01-01

    Polyacrylonitrile-co-methacrylic acid (PAN-co-MAA) and cellulose nanocrystal (CNC) composite films were produced with up to 40 wt% CNC loading through the solution casting method. The rheological properties of the solution/suspensions and the structural, optical, thermal, and mechanical properties of the resulting films were investigated. The viscosity of the composite...

  10. Preparation of amino-functionalized regenerated cellulose membranes with high catalytic activity.

    Science.gov (United States)

    Wang, Wei; Bai, Qian; Liang, Tao; Bai, Huiyu; Liu, Xiaoya

    2017-09-01

    The modification of regenerated cellulose (RC) membranes was carried out by using silane coupling agents presenting primary and secondary amino-groups. The grafting of the amino groups onto the modified cellulose molecule was confirmed by X-ray photoelectron spectroscopies and (13)C nuclear magnetic resonance spectroscopic analyses. The crystallinity of the cellulose membranes (CM) decreased after chemical modification as indicated by the X-ray diffraction results. Moreover, a denser structure was observed at the surface and cross section of the modified membranes by SEM images. The contact angle measurements showed that the silane coupling treatment enhanced the hydrophobicity of the obtained materials. Then the catalytic properties of two types of modified membranes were studied in a batch process by evaluating their catalytic performance in a Knoevenagel condensation. The results indicated that the cellulose membrane grafted with many secondary amines exhibited a better catalytic activity compared to the one grafted only by primary amines. In addition, the compact structure of the modified membranes permitted their application in a pervaporation catalytic membrane reactor. Therefore, functional CM that prepared in this paper represented a promising material in the field of industrial catalysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Scanning Electron Microscopy and Kinetic Studies of Ketene-Acetylated Wood/Cellulose High-Density Polyethylene Blends

    Directory of Open Access Journals (Sweden)

    Yakubu Azeh

    2012-01-01

    Full Text Available Acetylated cellulose and wood cellulose as well as untreated cellulose polyethylene blends were subjected to kinetic studies using water, 0.5 M NaOH, and 0.5 M HCl solutions in order to investigate their absorbent properties at 0.5/1.0 cellulose/wood cellulose/polyethylene matrix. The results of the absorption studies showed that the untreated cellulose and wood cellulose blends absorbed water and the acid and alkali solutions higher than the treated samples, which showed a reduction in acid, alkali, and water uptake. In this work, the effects of acetylation on the morphological studies of the polyethylene blends were obvious. The presence of acetyl groups improved the interfacial bonding between the polymer matrix and cellulose as well as the wood cellulose fibers, as evidenced by scanning electron microscopy (SEM.

  12. Cellulose Isolation Methodology for NMR Analysis of Cellulose Ultrastructure

    Directory of Open Access Journals (Sweden)

    Art J. Ragauskas

    2011-11-01

    Full Text Available In order to obtain accurate information about the ultrastructure of cellulose from native biomass by 13C cross polarization magic angle spinning (CP/MAS NMR spectroscopy the cellulose component must be isolated due to overlapping resonances from both lignin and hemicellulose. Typically, cellulose isolation has been achieved via holocellulose pulping to remove lignin followed by an acid hydrolysis procedure to remove the hemicellulose components. Using 13C CP/MAS NMR and non-linear line-fitting of the cellulose C4 region, it was observed that the standard acid hydrolysis procedure caused an apparent increase in crystallinity of ~10% or less on the cellulose isolated from Populus holocellulose. We have examined the effect of the cellulose isolation method, particularly the acid treatment time for hemicellulose removal, on cellulose ultrastructural characteristics by studying these effects on cotton, microcrystalline cellulose (MCC and holocellulose pulped Populus. 13C CP/MAS NMR of MCC indicated that holocellulose pulping and acid hydrolysis has little effect on the crystalline ultrastructural components of cellulose. Although any chemical method to isolate cellulose from native biomass will invariably alter substrate characteristics, especially those related to regions accessible to solvents, we found those changes to be minimal and consistent in samples of typical crystallinity and lignin/hemicellulose content. Based on the rate of the hemicellulose removal, as determined by HPLC-carbohydrate analysis and magnitude of cellulose ultrastructural alteration, the most suitable cellulose isolation methodology utilizes a treatment of 2.5 M HCl at 100 °C for a standard residence time between 1.5 and 4 h. However, for the most accurate crystallinity results this residence time should be determined empirically for a particular sample.

  13. Decomposition of Cellulose by Continuous Near-Critical Water Reactions

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A pilot-scale apparatus for continuous supercritical and near-critical water reaction was set up. A high- pressure slurry supplying system was developed to feed the solid material-water slurries. The apparatus features temperature up to 600℃, pressure up to 40MPa, residence time from 24s to 15min, maximum amount of slurry supply of 2.4 L.h-1, maximum solid content of slurry up to 10%(by mass) for cellulose from Merck, and resistance to corrosion. Long-time runs of decomposition of cellulose were carried out and steady runs were confirmed. Kinetics of cellulose decomposition was studied. The apparent activation energy evaluated was 147kJ·mol-1. In addition, a new three-step pathway for cellulose hydrolysis was proposed. The derived kinetic equation is in good agreement with the experimental data.

  14. Platelet adhesion, contact phase coagulation activation, and C5a generation of polyethylene glycol acid-grafted high flux cellulosic membrane with varieties of grafting amounts.

    Science.gov (United States)

    Fushimi, F; Nakayama, M; Nishimura, K; Hiyoshi, T

    1998-10-01

    Grafting of polyethylene glycol chains onto cellulosic membrane can be expected to reduce the interaction between blood (plasma protein and cells) and the membrane surface. Alkylether carboxylic acid (PEG acid) grafted high flux cellulosic membranes for hemodialysis, in which the polyethylene glycol chain bears an alkyl group at one side and a carboxyl group at the other side, have been developed and evaluated. PEG acid-grafted high flux cellulosic membranes with various grafting amounts have been compared with respect to platelet adhesion, the contact phase of blood coagulation, and complement activation in vitro. A new method of quantitating platelet adhesion on hollow-fiber membrane surfaces has been developed, which is based on the determination of lactate dehydrogenase (LDH) activity after lysis of the adhered platelets. PEG acid-grafted high flux cellulosic membranes showed reduced platelet adhesion and complement activation effects in grafting amounts of 200 ppm or higher without detecting adverse effects up to grafting amounts of 850 ppm. The platelet adhesion of a PEG acid-grafted cellulosic membrane depends on both the flux and grafting amounts of the membrane. It is concluded that the grafting of PEG acid onto a cellulosic membrane improves its biocompatibility as evaluated in terms of platelet adhesion, complement activation, and thrombogenicity.

  15. Gluconacetobacter hansenii subsp. nov., a high-yield bacterial cellulose producing strain induced by high hydrostatic pressure.

    Science.gov (United States)

    Ge, Han-Jing; Du, Shuang-Kui; Lin, De-Hui; Zhang, Jun-Na; Xiang, Jin-Le; Li, Zhi-Xi

    2011-12-01

    Strain M(438), deposited as CGMCC3917 and isolated from inoculums of bacterial cellulose (BC) producing strain screened in homemade vinegar and then induced by high hydrostatic pressure treatment (HHP), has strong ability to produce BC more than three times as that of its initial strain. It is the highest yield BC-producing strain ever reported. In this paper, M(438) was identidied as Gluconacetobacter hansenii subsp. nov. on the basis of the results obtained by examining it phylogenetically, phenotypically, and physiologically-biochemically. Furthermore, the genetic diversity of strain M(438) and its initial strain was examined by amplified fragment length polymorphism. The results indicated that strain M(438) was a deletion mutant induced by HHP, and the only deleted sequence showed 99% identity with 24,917-24,723 bp in the genome sequence of Ga. hansenii ATCC23769, and the complement gene sequence was at 24,699-25,019 bp with local tag GXY_15142, which codes small multidrug resistance (SMR) protein. It can be inferred that SMR might be related to inhibiting BC production to a certain extent.

  16. Utilization of residues from agro-forest industries in the production of high value bacterial cellulose.

    Science.gov (United States)

    Carreira, Pedro; Mendes, Joana A S; Trovatti, Eliane; Serafim, Luísa S; Freire, Carmen S R; Silvestre, Armando J D; Neto, Carlos Pascoal

    2011-08-01

    Bacterial cellulose (BC), a very peculiar form of cellulose, is gaining considerable importance due to its unique properties. In this study, several residues, from agro-forestry industries, namely grape skins aqueous extract, cheese whey, crude glycerol and sulfite pulping liquor were evaluated as economic carbon and nutrient sources for the production of BC. The most relevant BC amounts attained with the residues from the wine and pulp industries were 0.6 and 0.3 g/L, respectively, followed by biodiesel crude residue and cheese whey with productions of about, 0.1 g/L after 96 h of incubation. Preliminary results on the addition of other nutrient sources (yeast extract, nitrogen and phosphate) to the residues-based culture media indicated that, in general, these BC productions could be increased by ~200% and ~100% for the crude glycerol and grape skins, respectively, after the addition organic or inorganic nitrogen.

  17. Water-soluble nanocrystalline cellulose films with highly transparent and oxygen barrier properties

    Science.gov (United States)

    Cheng, Shaoling; Zhang, Yapei; Cha, Ruitao; Yang, Jinliang; Jiang, Xingyu

    2015-12-01

    By mixing a guar gum (GG) solution with a nanocrystalline cellulose (NCC) dispersion using a novel circular casting technology, we manufactured biodegradable films as packaging materials with improved optical and mechanical properties. These films could act as barriers for oxygen and could completely dissolve in water within 5 h. We also compared the effect of nanocomposite films and commercial food packaging materials on the preservation of food.By mixing a guar gum (GG) solution with a nanocrystalline cellulose (NCC) dispersion using a novel circular casting technology, we manufactured biodegradable films as packaging materials with improved optical and mechanical properties. These films could act as barriers for oxygen and could completely dissolve in water within 5 h. We also compared the effect of nanocomposite films and commercial food packaging materials on the preservation of food. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr07647a

  18. Cellulose Tailored Anatase TiO2 Nanospindles in Three-Dimensional Graphene Composites for High-Performance Supercapacitors.

    Science.gov (United States)

    Ding, Yangbin; Bai, Wei; Sun, Jinhua; Wu, Yu; Memon, Mushtaque A; Wang, Chao; Liu, Chengbin; Huang, Yong; Geng, Jianxin

    2016-05-18

    The morphologies of transition metal oxides have decisive impact on the performance of their applications. Here, we report a new and facile strategy for in situ preparation of anatase TiO2 nanospindles in three-dimensional reduced graphene oxide (RGO) structure (3D TiO2@RGO) using cellulose as both an intermediate agent eliminating the negative effect of graphene oxide (GO) on the growth of TiO2 crystals and as a structure-directing agent for the shape-controlled synthesis of TiO2 crystals. High-resolution transmission electron microscopy and X-ray diffractometer analysis indicated that the spindle shape of TiO2 crystals was formed through the restriction of the growth of high energy {010} facets due to preferential adsorption of cellulose on these facets. Because of the 3D structure of the composite, the large aspect ratio of the TiO2 nanospindles, and the exposed high-energy {010} facets of the TiO2 crystals, the 3D TiO2@RGO(Ce 1.7) exhibited excellent capacitive performance as an electrode material for supercapacitors, with a high specific capacitance (ca. 397 F g(-1)), a high energy density (55.7 Wh kg(-1)), and a high power density (1327 W kg(-1)) on the basis of the masses of RGO and TiO2. These levels of capacitive performance far exceed those of previously reported TiO2-based composites.

  19. A comparison of partially acetylated nanocellulose, nanocrystalline cellulose, and nanoclay as fillers for high-performance polylactide nanocomposites

    DEFF Research Database (Denmark)

    Trifol Guzman, Jon; Plackett, David; Sillard, Cecile

    2016-01-01

    Partially acetylated cellulose nanofibers (CNF) were chemically extracted from sisal fibers and the performance of those CNF as nanofillers for polylactide (PLA) for food packaging applications was evaluated. Three PLA nanocomposites; PLA/CNF (cellulose nanofibers), PLA/CNC (nanocrystalline...

  20. Analysis of the origins of content non-uniformity in high-shear wet granulation.

    Science.gov (United States)

    Oka, Sarang; Smrčka, David; Kataria, Anjali; Emady, Heather; Muzzio, Fernando; Štěpánek, František; Ramachandran, Rohit

    2017-08-07

    In this study, the origins of granule content non-uniformity in the high-shear wet granulation of a model two-component pharmaceutical blend were investigated. Using acetaminophen as the active pharmaceutical ingredient (API) and microcrystalline cellulose as the excipient, the distribution of the API across the granule size classes was measured for a range of conditions that differed in the duration of the initial dry mixing stage, the overall composition of the blend and the wet massing time. The coarse granule fractions were found to be systematically sub-potent, while the fines were enriched in the API. The extent of content non-uniformity was found to be dependent on two factors - powder segregation during dry mixing and redistribution of the API between the granule size fractions during the wet massing phase. The latter was demonstrated in an experiment where the excipient was pre-granulated, the API was added later and wet massed. The content non-uniformity in this case was comparable to that obtained when both components were present in the granulator from the beginning. With increasing wet massing time, the extent of content non-uniformity decreased, indicating that longer wet massing times might be a solution for systems with a natural tendency for component segregation. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. High-yield production of extracellular type-I cellulose by the cyanobacterium Synechococcus sp. PCC 7002

    OpenAIRE

    Zhao, Chi; Li,Zhongkui; Li, Tao; Zhang, Yingjiao; Bryant, Donald A.; Zhao, Jindong

    2015-01-01

    Cellulose synthase, encoded by the cesA gene, is responsible for the synthesis of cellulose in nature. We show that the cell wall of the cyanobacterium Synechococcus sp. PCC 7002 naturally contains cellulose. Cellulose occurs as a possibly laminated layer between the inner and outer membrane, as well as being an important component of the extracellular glycocalyx in this cyanobacterium. Overexpression of six genes, cmc–ccp–cesAB–cesC–cesD–bgl, from Gluconacetobacter xylinus in Synechococcus s...

  2. Optimization the soda-AQ process for cellulose pulp production and energy content of black liquor from L. leucocephala K360.

    Science.gov (United States)

    Feria, M J; García, J C; Díaz, M J; Garrote, G; López, F

    2012-09-01

    A commercial variety of Leucaena leucocephala K360 was used for pulp production and papermaking employing the soda-anthraquinone process. Also, the chemical and energy contents of the resultant black liquors were determined to simultaneously optimize: pulp and paper production and energy generation. A process temperature of (185°C), an operating time of (120 min) and an active alkali concentration of (21%) provided sheets of paper with good strength (tensile index of 12.12 Nm/g, burst index of 0.38 kPa m(2)/g, tear index of 1.29 mN m(2)/g and a Kappa number of 20.5) and black liquor with a greater calorific value (14.1 MJ/kg) than that obtained with higher active alkali concentrations. However, reducing the active alkali concentration to a level in the low operation range led to less marked degradation of cellulose and allowed paper sheets with good properties to be obtained and energy to be optimally produced from the black liquor.

  3. Improved Release of Celecoxib from High Drug Loading Amorphous Solid Dispersions Formulated with Polyacrylic Acid and Cellulose Derivatives.

    Science.gov (United States)

    Xie, Tian; Taylor, Lynne S

    2016-03-07

    Amorphous solid dispersions (ASDs) have been extensively exploited as a strategy for improving the dissolution performance of poorly water-soluble drugs. However, factors underpinning the observed dissolution profiles are not clearly understood, and the choice of polymeric carriers is largely empirical. In the current study, the dissolution performance of a high drug loading ASD containing the poorly water-soluble, anti-inflammatory agent, celecoxib, was optimized by using binary polymers combinations. Polyacrylic acid (PAA), a highly water-soluble polymer, was used to substantially increase the dissolution rate of the drug, while hydroxypropyl methyl cellulose (HPMC) or HPMC acetate succinate (HPMCAS) were added to stabilize the solid amorphous matrix against crystallization upon hydration, as well as to maintain supersaturation. Quantitative measurements of the impact of the polymers on the solution nucleation and growth rates of celecoxib revealed that, while the cellulose derivatives are effective nucleation inhibitors, it is more difficult to completely prevent crystal growth in solutions containing seed crystals, in particular at high supersaturations. Therefore, it is critical to prevent the formation of crystals in the dissolving matrix during dissolution. By using certain ratios of HPMC and PAA, both rapid release as well as crystallization inhibition could be achieved, even at high drug loadings. Utilizing combinations of polymers may therefore be useful to tailor release profiles while providing optimized crystallization inhibition.

  4. Enzymatic and chemical treatments to obtain pulps with high-cellulose content

    OpenAIRE

    Quintana Vilajuana, Elisabet

    2016-01-01

    La celulosa es el polímero más abundante en la Tierra y en los últimos años ha ganado un amplio interés como fuente de nuevos productos con requisitos de procesamiento y de calidad diferentes a los procesos convencionales de obtención de pulpa y papel. Las restricciones en el cultivo de algodón y el aumento de la producción de las llamadas pulpas para disolver (dissolving pulps) ofrecen nuevas oportunidades al polímero de celulosa. Además, en comparación con los productos químicos derivados d...

  5. Utilization of potato starch processing wastes to produce animal feed with high lysine content.

    Science.gov (United States)

    Li, Ying; Liu, Bingnan; Song, Jinzhu; Jiang, Cheng; Yang, Qian

    2015-02-01

    This work aims to utilize wastes from the potato starch industry to produce single-cell protein (SCP) with high lysine content as animal feed. In this work, S-(2-aminoethyl)-L-cysteine hydrochloride-resistant Bacillus pumilus E1 was used to produce SCP with high lysine content, whereas Aspergillus niger was used to degrade cellulose biomass and Candida utilis was used to improve the smell and palatability of the feed. An orthogonal design was used to optimize the process of fermentation for maximal lysine content. The optimum fermentation conditions were as follows: temperature of 40°C, substrate concentration of 3%, and natural pH of about 7.0. For unsterilized potato starch wastes, the microbial communities in the fermentation process were determined by terminal restriction fragment length polymorphism analysis of bacterial 16S rRNA genes. Results showed that the dominant population was Bacillus sp. The protein quality as well as the amino acid profile of the final product was found to be significantly higher compared with the untreated waste product at day 0. Additionally, acute toxicity test showed that the SCP product was non-toxic, indicating that it can be used for commercial processing.

  6. Cast Iron With High Carbon Content

    Science.gov (United States)

    Curreri, P. A.; Hendrix, J. C.; Stefanescu, D. M.

    1986-01-01

    Method proposed for solidifying high-carbon cast iron without carbon particles segregating at upper surface. Solidification carried out in low gravity, for example on airplane flying free-fall parabolic trajectory. Many different microstructures obtained by proposed technique, and percentage by weight of carbon retained in melt much higher than at present.

  7. Inability of Microorganisms To Degrade Cellulose Acetate Reverse-Osmosis Membranes †

    Science.gov (United States)

    Ho, Leighton C. W.; Martin, David D.; Lindemann, William C.

    1983-01-01

    Operational cellulose acetate reverse-osmosis membranes were examined for evidence of biological degradation. Numerous fungi and bacteria were isolated by direct and enrichment techniques. When tested, most of the fungi were active cellulose degraders, but none of the bacteria were. Neither fungi nor bacteria were able to degrade cellulose acetate membrane in vitro, although many fungi were able to degrade cellulose acetate membrane after it had been deacetylated. Organisms did not significantly degrade powdered cellulose acetate in pure or mixed cultures as measured by reduction in acetyl content or intrinsic viscosity or production of reducing sugars. Organisms did not affect the performance of cellulose triacetate fibers when incubated with them. The inability of the organisms to degrade cellulose acetate was attributed to the high degree of acetate substitution of the cellulose polymer. The rate of salt rejection decline was strongly correlated with chlorination of feed water and inversely with densities of microorganisms. These data suggest that microbial degradation of operational cellulose acetate reverse-osmosis membranes is unlikely. PMID:16346192

  8. Cellulose is not just cellulose

    DEFF Research Database (Denmark)

    Hidayat, Budi Juliman; Felby, Claus; Johansen, Katja Salomon

    2012-01-01

    or enzymatic hydrolysis of plant cell walls is carried out simultaneously with the application of shear stress, plant cells such as fibers or tracheids break at their dislocations. At present it is not known whether specific carbohydrate binding modules (CBMs) and/or cellulases preferentially access cellulose......Most secondary plant cell walls contain irregular regions known as dislocations or slip planes. Under industrial biorefining conditions dislocations have recently been shown to play a key role during the initial phase of the enzymatic hydrolysis of cellulose in plant cell walls. In this review we...... are not regions where free cellulose ends are more abundant than in the bulk cell wall. In more severe cases cracks between fibrils form at dislocations and it is possible that the increased accessibility that these cracks give is the reason why hydrolysis of cellulose starts at these locations. If acid...

  9. Cellulose crystallinity index: measurement techniques and their impact on interpreting cellulase performance.

    Science.gov (United States)

    Park, Sunkyu; Baker, John O; Himmel, Michael E; Parilla, Philip A; Johnson, David K

    2010-05-24

    Although measurements of crystallinity index (CI) have a long history, it has been found that CI varies significantly depending on the choice of measurement method. In this study, four different techniques incorporating X-ray diffraction and solid-state 13C nuclear magnetic resonance (NMR) were compared using eight different cellulose preparations. We found that the simplest method, which is also the most widely used, and which involves measurement of just two heights in the X-ray diffractogram, produced significantly higher crystallinity values than did the other methods. Data in the literature for the cellulose preparation used (Avicel PH-101) support this observation. We believe that the alternative X-ray diffraction (XRD) and NMR methods presented here, which consider the contributions from amorphous and crystalline cellulose to the entire XRD and NMR spectra, provide a more accurate measure of the crystallinity of cellulose. Although celluloses having a high amorphous content are usually more easily digested by enzymes, it is unclear, based on studies published in the literature, whether CI actually provides a clear indication of the digestibility of a cellulose sample. Cellulose accessibility should be affected by crystallinity, but is also likely to be affected by several other parameters, such as lignin/hemicellulose contents and distribution, porosity, and particle size. Given the methodological dependency of cellulose CI values and the complex nature of cellulase interactions with amorphous and crystalline celluloses, we caution against trying to correlate relatively small changes in CI with changes in cellulose digestibility. In addition, the prediction of cellulase performance based on low levels of cellulose conversion may not include sufficient digestion of the crystalline component to be meaningful.

  10. [Determination of sugars, organic acids and alcohols in microbial consortium fermentation broth from cellulose using high performance liquid chromatography].

    Science.gov (United States)

    Jiang, Yan; Fan, Guifang; Du, Ran; Li, Peipei; Jiang, Li

    2015-08-01

    A high performance liquid chromatographic method was established for the determination of metabolites (sugars, organic acids and alcohols) in microbial consortium fermentation broth from cellulose. Sulfate was first added in the samples to precipitate calcium ions in microbial consortium culture medium and lower the pH of the solution to avoid the dissociation of organic acids, then the filtrates were effectively separated using high performance liquid chromatography. Cellobiose, glucose, ethanol, butanol, glycerol, acetic acid and butyric acid were quantitatively analyzed. The detection limits were in the range of 0.10-2.00 mg/L. The linear correlation coefficients were greater than 0.999 6 in the range of 0.020 to 1.000 g/L. The recoveries were in the range of 85.41%-115.60% with the relative standard deviations of 0.22% -4.62% (n = 6). This method is accurate for the quantitative analysis of the alcohols, organic acids and saccharides in microbial consortium fermentation broth from cellulose.

  11. Hybrid nanocomposites based on electroactive hydrogels and cellulose nanocrystals for high-sensitivity electro-mechanical underwater actuation

    Science.gov (United States)

    Santaniello, Tommaso; Migliorini, Lorenzo; Locatelli, Erica; Monaco, Ilaria; Yan, Yunsong; Lenardi, Cristina; Comes Franchini, Mauro; Milani, Paolo

    2017-08-01

    We report the synthesis, fabrication and characterization of a hybrid hydrogel/cellulose nanocomposite, which exhibits high-performance electro-mechanical underwater actuation and high sensitivity in response to electrical stimuli below the standard potential of water electrolysis. The macromolecular structure of the material is constituted by an electroactive hydrogel, obtained through a photo-polymerization reaction with the use of three vinylic co-monomers: Na-4-vinylbenzenesulfonate, 2-hydroxyethylmethacrylate, and acrylonitrile. Different amounts (from 0.1% to 1.4% w/w) of biodegradable cellulose nanocrystals (CNCs) with sulfonate surface groups, obtained through the acidic hydrolysis of sulphite pulp lapsheets, are physically incorporated into the gel matrix during the synthesis step. Freestanding thin films of the nanocomposites are molded, and their swelling, mechanical and responsive properties are fully characterized. We observed that the embedding of the CNCs enhanced both the material Young’s modulus and its sensitivity to the applied electric field in the sub-volt regime (down to 5 mV cm-1). A demonstrator integrating multiple actuators that cooperatively bend together, mimicking the motion of an electro-valve, is also prototyped and tested. The presented nanocomposite is suitable for the development of soft smart components for bio-robotic applications and cells-based and bio-hybrid fluidic devices fabrication.

  12. Sustainable, heat-resistant and flame-retardant cellulose-based composite separator for high-performance lithium ion battery

    Science.gov (United States)

    Zhang, Jianjun; Yue, Liping; Kong, Qingshan; Liu, Zhihong; Zhou, Xinhong; Zhang, Chuanjian; Xu, Quan; Zhang, Bo; Ding, Guoliang; Qin, Bingsheng; Duan, Yulong; Wang, Qingfu; Yao, Jianhua; Cui, Guanglei; Chen, Liquan

    2014-02-01

    A sustainable, heat-resistant and flame-retardant cellulose-based composite nonwoven has been successfully fabricated and explored its potential application for promising separator of high-performance lithium ion battery. It was demonstrated that this flame-retardant cellulose-based composite separator possessed good flame retardancy, superior heat tolerance and proper mechanical strength. As compared to the commercialized polypropylene (PP) separator, such composite separator presented improved electrolyte uptake, better interface stability and enhanced ionic conductivity. In addition, the lithium cobalt oxide (LiCoO2)/graphite cell using this composite separator exhibited better rate capability and cycling retention than that for PP separator owing to its facile ion transport and excellent interfacial compatibility. Furthermore, the lithium iron phosphate (LiFePO4)/lithium cell with such composite separator delivered stable cycling performance and thermal dimensional stability even at an elevated temperature of 120°C. All these fascinating characteristics would boost the application of this composite separator for high-performance lithium ion battery.

  13. The rheological properties of modified microcrystalline cellulose containing high levels of model drugs.

    Science.gov (United States)

    Knight, Paul E; Podczeck, Fridrun; Newton, J Michael

    2009-06-01

    The rheological properties of different types of microcrystalline cellulose (MCC) mixed with model drugs and water have been evaluated to identify the influence of sodium carboxymethylcellulose (SCMC) added to the cellulose during preparation. A ram extruder was used as a capillary rheometer. The mixtures consisted of 20% spheronizing agent (standard grade MCC or modified types with 6% or 8% of low viscosity grade SCMC) and 80% of ascorbic acid, ibuprofen or lactose monohydrate. The introduction of SCMC changed all rheological parameters assessed. It produced more rigid systems, requiring more stress to induce and maintain flow. Degree of non-Newtonian flow, angle of convergence, extensional viscosity, yield and die land shear stress at zero velocity, and static wall friction were increased, but recoverable shear and compliance were decreased. The presence of SCMC did not remove the influence of the type of drug. The mixture of ibuprofen and standard MCC had the lowest values for shear stress as a function of the rate of shear, extensional viscosity, and angle of convergence, but the highest values for recoverable shear and compliance. The findings indicate that the system has insufficient rigidity to form pellets.

  14. Modification of Corn Starch Ethanol Refinery to Efficiently Accept Various High-Impact Cellulosic Feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Derr, Dan

    2013-12-30

    The goal of the Corn-to-Cellulosic Migration (CCM) pilot facility was to demonstrate the implementation of advanced technologies and methods for conversion of non-food, cellulosic feedstocks into ethanol, assess the economics of the facility and evaluate potential environmental benefits for biomass to fuels conversion. The CCM project was comprised of design, build, and operate phases for the CCM pilot facility as well as research & development, and modeling components. The CCM pilot facility was designed to process 1 tonne per day of non-food biomass and biologically convert that biomass to ethanol at a rate of 70 gallons per tonne. The plant demonstrated throughputs in excess of 1 tonne per day for an extended run of 1400 hours. Although target yields were not fully achieved, the continuous operation validated the design and operability of the plant. These designs will permit the design of larger scale operations at existing corn milling operations or for greenfield plants. EdeniQ, a partner in the project and the owner of the pilot plant, continues to operate and evaluate other feedstocks.

  15. Drying of Pigment-Cellulose Nanofibril Substrates

    Directory of Open Access Journals (Sweden)

    Oleg Timofeev

    2014-10-01

    Full Text Available A new substrate containing cellulose nanofibrils and inorganic pigment particles has been developed for printed electronics applications. The studied composite structure contains 80% fillers and is mechanically stable and flexible. Before drying, the solids content can be as low as 20% due to the high water binding capacity of the cellulose nanofibrils. We have studied several drying methods and their effects on the substrate properties. The aim is to achieve a tight, smooth surface keeping the drying efficiency simultaneously at a high level. The methods studied include: (1 drying on a hot metal surface; (2 air impingement drying; and (3 hot pressing. Somewhat surprisingly, drying rates measured for the pigment-cellulose nanofibril substrates were quite similar to those for the reference board sheets. Very high dewatering rates were observed for the hot pressing at high moisture contents. The drying method had significant effects on the final substrate properties, especially on short-range surface smoothness. The best smoothness was obtained with a combination of impingement and contact drying. The mechanical properties of the sheets were also affected by the drying method and associated temperature.

  16. Cellulose binding domain fusion proteins

    Science.gov (United States)

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc A.; Doi, Roy H.

    1998-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  17. 硝酸乙醇法测定纤维素含量%Determination the content of cellulose by nitric acid-ethanol method

    Institute of Scientific and Technical Information of China (English)

    王林风; 程远超

    2011-01-01

    根据秸秆乙醇的工艺特点,对硝酸乙醇法测定玉米秸秆、小麦秸秆、稻草及其预处理后物料的纤维素含量进行了研究.优化了粉碎时长、硝酸-乙醇混合液处理遍数、试样粒度及抽滤漏斗孔径四个参数.确定了优化后的测定方法:秸秆试样粉碎时长15 s,硝酸-乙醇混合液处理4遍,粒度40~60目,使用G2玻璃砂芯漏斗.秸秆预处理后物料试样粉碎时长3 s,硝酸-乙醇混合液处理3遍,粒度40~60目,使用G3玻璃砂芯漏斗.%The contents of cellulose of corn stalk, wheat straw, rice straw and the pretreated sample of straws have been researched by nitric acid-ethanol methodology according to the characteristics of straws biofuel ethanol. Four parameters as the duration of comminuting sample, the times of treating sample by nitric acid-ethanol liquid mixture, the particle size of sample and the aperture of tundish for sucking filtration have been optimized. The optimized pev-rameters: for straw sample, comminut 15 s, treat by nitric acid-ethanol liquid mixture 4 times, sample aperture 40 - 60 mesh, use G2 glass sand core tundish. For pretreated sample, comminut 3 s, treat by nitric acid-ethanol liquid mixture 3 times, sample aperture 40 - 60 mesh, use G3 glass sand core tundish.

  18. Superhydrophobic and highly luminescent polyfluorene/silica hybrid coatings deposited onto glass and cellulose-based substrates.

    Science.gov (United States)

    de Francisco, Raquel; Hoyos, Mario; García, Nuria; Tiemblo, Pilar

    2015-03-31

    Neat poly(9,9-dioctyl-9H-fluorene) (PFO) and composites of PFO and a modified organonanosilica P(7) at weight ratios 90/10, 70/30, and 50/50 have been employed to prepare fluorescent and superhydrophobic coatings by spraying onto three different substrates: glass, Whatman paper, and a filtration membrane of mixed cellulose esters. The water repellency of the coatings and their photophysical properties are therein studied. It is found that, irrespective of the substrate and the composite composition, all coatings remain fluorescent. In some of the coatings prepared, confined morphologies are created, which fluoresce with a wavelength distribution resembling that of an ordered planar β-phase. Among the coatings prepared in this work, those with a ratio PFO/P(7) of 50/50 are the ones with the strongest chain confinement and the highest surface roughness, being highly emissive at the β-phase wavelengths and also superhydrophobic. Depending on the substrate these materials are also tough and flexible (cellulose based substrates) or display a remarkable light transmittance (glass). A final merit of these multifunctional materials is the simplicity of the preparation procedure, adequate for large surfaces and industrial applications.

  19. The silica-doped sulfonated poly(fluorenyl ether ketone)s membrane using hydroxypropyl methyl cellulose as dispersant for high temperature proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y.F.; Wang, S.J.; Xiao, M.; Bian, S.G.; Meng, Y.Z. [State Key Laboratory of Optoelectronic Materials and Technologies, Institute of Optoelectronic and Functional Composite Materials, Sun Yat-sen University, Xingangxi Road, Guangzhou 510275 (China)

    2009-05-15

    The sulfonated poly(fluorenyl ether ketone)s (SPFEK) membranes doped with SiO{sub 2} and dispersed by hydroxypropyl methyl cellulose (HPMC) were prepared and investigated for polymer electrolyte membrane fuel cells (PEMFCs) used at high temperature and low relative humidity (RH). The above membrane was prepared by solution dispersion of SPFEK and SiO{sub 2} using HPMC as dispersant. The physio-chemical properties of the hybrid membrane were studied by means of scanning electron microscope (SEM), ion-exchange capacity (IEC), proton conductivity, and single cell performance tests. The hybrid membranes dispersed by HPMC were well dispersed when compared with common organic/inorganic hybrid membranes. The hybrid membranes showed superior characteristics as a proton exchange membrane (PEM) for PEMFC application, such as high ionic exchange content (IEC) of 1.51 equiv/g, high temperature operation properties, and the satisfactory ability of anti-H{sub 2} crossover. The single cell performances of the hybrid membranes were examined in a 5 cm{sup 2} commercial single cell at both 80 C and 120 C under different relative humidity (RH) conditions. The hybrid membrane dispersed by HPMC gave the best performance of 260 mW/cm{sup 2} under conditions of 0.4 V, 120 C, 50% RH and ambient pressure. The results demonstrated HPMC being an efficient dispersant for the organic/inorganic hybrid membrane used for PEM fuel cell. (author)

  20. Isolation and characteristics analysis of a novel high bacterial cellulose producing strain Gluconacetobacter intermedius CIs26.

    Science.gov (United States)

    Yang, Ying; Jia, Jingjing; Xing, Jianrong; Chen, Jianbing; Lu, Shengmin

    2013-02-15

    A strain producing bacterial cellulose (BC) screened from rotten mandarin fruit was identified as Gluconacetobacter intermedius CIs26 by the examination of general taxonomical characteristics and 16S rDNA sequence analysis. Furthermore, Fourier transform infrared (FT-IR) spectrum showed that pellicle produced by strain CIs26 was composed of glucan, and had the same functional group as a typical BC. X-ray diffractometry (XRD) analysis indicated that the BC was type I in structure with crystallinity index of 75%. BC yields of strain CIs26 in Hestrin-Schramn (HS), citrus waste modified HS (CMHS) and citrus waste solution (CWS) mediums were 2.1 g/L, 5.7 g/L, and 7.2 g/L, respectively. It was shown that citrus waste could stimulate BC production of strain CIs26 efficiently. Based on the ability of utilization of citrus waste, this strain appeared to have potential in BC manufacture on an industrial scale.

  1. Modified coaxial electrospinning for the preparation of high-quality ketoprofen-loaded cellulose acetate nanofibers.

    Science.gov (United States)

    Yu, Deng-Guang; Yu, Jia-Hui; Chen, Lan; Williams, Gareth R; Wang, Xia

    2012-10-01

    This study investigates the use of a modified coaxial electrospinning process in the production of drug-loaded cellulose acetate (CA) nanofibers. With CA employed as a filament-forming matrix and ketoprofen (KET) as an active pharmaceutical ingredient, modified coaxial processes using sheath fluids comprising only mixed solvents were undertaken. With a sheath-to-core flow rate ratio of 0.2:1, the nanofibers prepared from the coaxial process had a smaller average diameter, narrower size distribution, more uniform structures, and smoother surface morphologies than those generated from single fluid electrospinning. In addition, the coaxial fibers provided a better zero-order drug release profile. The use of a sheath solvent means that the core jet is subjected to electrical drawing for a longer period, facilitating homogeneous core jet solidification and retarding the formation of wrinkles on the surface of the nanofibers. This modified coaxial electrospinning protocol allows the systematic fabrication of functional polymer nanofibers with improved quality.

  2. Cellulose acetate-directed growth of bamboo-raft-like single-crystalline selenium superstructures: high-yield synthesis, characterization, and formation mechanism.

    Science.gov (United States)

    Song, Ji-Ming; Zhan, Yong-Jie; Xu, An-Wu; Yu, Shu-Hong

    2007-06-19

    High-yield synthesis of bamboo-raft-like single-crystalline selenium superstructures has been realized for the first time via a facile solvothermal approach by reducing SeO2 with ethylene alcohol in the presence of cellulose acetate. The formation of a raftlike superstructure with various forms is strongly dependent on the temperature, amount of cellulose acetate, reaction time, and even preheating treatment. The suitable amount of cellulose acetate is essential for the formation of elegant and uniform raft Se. The morphology, microstructure, optical properties, and chemical compositions of bamboo-raft-like selenium were characterized using various techniques (X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy (TEM), high-resolution (HR) TEM, X-ray photoelectron spectroscopy, UV-vis spectroscopy, FTIR spectroscopy, and Raman spectroscopy). A possible growth mechanism has been proposed. Such special superstructures could provide a useful precursor for potential applications.

  3. Photoresponsive Cellulose Nanocrystals

    Directory of Open Access Journals (Sweden)

    Dimitris S Argyropoulos

    2011-07-01

    Full Text Available In this communication a method for the creation of fluorescent cellulose nanoparticles using click chemistry and subsequent photodimerization of the installed side‐ chains is demonstrated. In the first step, the primary hydroxyl groups on the surface of the CNCs were converted to carboxylic acids by using TEMPO‐mediated hypohalite oxidation. The alkyne groups, essential for the click reaction, were introduced into the surface of TEMPO‐ oxidized CNCs via carbodiimide‐mediated formation of an amide linkage between monomers carrying an amine functionality and carboxylic acid groups on the surface of the TEMPO‐oxidized CNCs. Finally, the reaction of surface‐modified TEMPO‐oxidized cellulose nanocrystals and azido‐bearing coumarin and anthracene monomers were carried out by means of a click chemistry, i.e., Copper(I‐catalyzed Azide‐Alkyne Cycloaddition (CuAAC to produce highly photo‐responsive and fluorescent cellulose nanoparticles. Most significantly, the installed coumarin and/or anthracene side‐chains were shown to undergo UV‐induced [2+2] and [4+4] cycloaddition reactions, bringing and locking the cellulose nanocrystals together. This effort paves the way towards creating, cellulosic photo responsive nano‐arrays with the potential of photo reversibility since these reactions are known to be reversible at varying wavelengths.

  4. COBRA, an Arabidopsis extracellular glycosyl-phosphatidyl inositol-anchored protein, specifically controls highly anisotropic expansion through its involvement in cellulose microfibril orientation.

    Science.gov (United States)

    Roudier, François; Fernandez, Anita G; Fujita, Miki; Himmelspach, Regina; Borner, Georg H H; Schindelman, Gary; Song, Shuang; Baskin, Tobias I; Dupree, Paul; Wasteneys, Geoffrey O; Benfey, Philip N

    2005-06-01

    The orientation of cell expansion is a process at the heart of plant morphogenesis. Cellulose microfibrils are the primary anisotropic material in the cell wall and thus are likely to be the main determinant of the orientation of cell expansion. COBRA (COB) has been identified previously as a potential regulator of cellulose biogenesis. In this study, characterization of a null allele, cob-4, establishes the key role of COB in controlling anisotropic expansion in most developing organs. Quantitative polarized-light and field-emission scanning electron microscopy reveal that loss of anisotropic expansion in cob mutants is accompanied by disorganization of the orientation of cellulose microfibrils and subsequent reduction of crystalline cellulose. Analyses of the conditional cob-1 allele suggested that COB is primarily implicated in microfibril deposition during rapid elongation. Immunodetection analysis in elongating root cells revealed that, in agreement with its substitution by a glycosylphosphatidylinositol anchor, COB was polarly targeted to both the plasma membrane and the longitudinal cell walls and was distributed in a banding pattern perpendicular to the longitudinal axis via a microtubule-dependent mechanism. Our observations suggest that COB, through its involvement in cellulose microfibril orientation, is an essential factor in highly anisotropic expansion during plant morphogenesis.

  5. Liquid crystalline solutions of cellulose in phosphoric acid for preparing cellulose yarns

    NARCIS (Netherlands)

    Boerstoel, H.

    2006-01-01

    The presen thesis describes a new process for manufacturing high tenacity and high modulus cellulose yarns. A new direct solvent for cellulose has been discovered, leading to liquid crystalline solutions. This new solvent, superphosphoric acid, rapidly dissolves cellulose. These liquid crystalline s

  6. The aluminium content of infant formulas remains too high

    OpenAIRE

    2013-01-01

    Background Recent research published in this journal highlighted the issue of the high content of aluminium in infant formulas. The expectation was that the findings would serve as a catalyst for manufacturers to address a significant problem of these, often necessary, components of infant nutrition. It is critically important that parents and other users have confidence in the safety of infant formulas and that they have reliable information to use in choosing a product with a lower content ...

  7. Prewashing enhances the liquid hot water pretreatment efficiency of waste wheat straw with high free ash content.

    Science.gov (United States)

    Huang, Chen; Wu, Xinxing; Huang, Yang; Lai, Chenhuan; Li, Xin; Yong, Qiang

    2016-11-01

    The effect of prewashing process prior to the liquid hot water (LHW) pretreatment of high free ash content waste wheat straw (WWS) was investigated. It was found that prewashing process decreased the ash content of WWS greatly, from 29.48% to 9.82%. This contributed to the lower pH value of prehydrolyzate and higher xylan removal in the following LHW pretreatment. More importantly, the prewashing process effectively increased the cellulose enzymatic hydrolysis efficiency of pretreated WWS, from 53.04% to 84.15%. The acid buffering capacity (ABC) and cation exchange capacity (CEC) of raw and prewashed WWS were examined. The majority of free ash removal from WWS by prewashing resulted in the decrease of the ABC of the WWS from 211.74 to 61.81mmol/pH-kg, and potentially enhancing the efficiency of the follow-up LHW pretreatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Base metal catalyzed graphitization of cellulose : A combined Raman spectroscopy, temperature-dependent X-ray diffraction and high-resolution transmission electron microscopy study

    NARCIS (Netherlands)

    Hoekstra, Jacco; Beale, Andrew M.; Soulimani, Fouad; Versluijs-Helder, Marjan; Geus, John W.; Jenneskens, Leonardus W.

    2015-01-01

    Microcrystalline cellulose (MCC) spheres homogeneously loaded with the nitrate salts of copper, nickel, cobalt, or iron are excellent model systems to establish the temperature at which highly dispersed base metal nanoparticles are formed as well as to establish the temperature at which catalytic gr

  9. Base metal catalyzed graphitization of cellulose : A combined Raman spectroscopy, temperature-dependent X-ray diffraction and high-resolution transmission electron microscopy study

    NARCIS (Netherlands)

    Hoekstra, Jacco; Beale, Andrew M.; Soulimani, Fouad; Versluijs-Helder, Marjan; Geus, John W.; Jenneskens, Leonardus W.

    2015-01-01

    Microcrystalline cellulose (MCC) spheres homogeneously loaded with the nitrate salts of copper, nickel, cobalt, or iron are excellent model systems to establish the temperature at which highly dispersed base metal nanoparticles are formed as well as to establish the temperature at which catalytic gr

  10. Increasing cellulose production and transgenic plant growth in forest tree species

    Institute of Scientific and Technical Information of China (English)

    TANG Wei; Aaron Nelson; Emmanuel Johnson

    2005-01-01

    effect of the antisense transgene expression on lignin content, cellulose accumulation, and loblolly pine biomass; and (4) select fast growth and high cellulose accumulation transgenic loblolly pine lines for future commercial application.

  11. Easy Fabrication of Highly Thermal-Stable Cellulose Nanocrystals Using Cr(NO33 Catalytic Hydrolysis System: A Feasibility Study from Macro- to Nano-Dimensions

    Directory of Open Access Journals (Sweden)

    You Wei Chen

    2017-01-01

    Full Text Available This study reported on the feasibility and practicability of Cr(NO33 hydrolysis to isolate cellulose nanocrystals (CNCCr(NO33 from native cellulosic feedstock. The physicochemical properties of CNCCr(NO33 were compared with nanocellulose isolated using sulfuric acid hydrolysis (CNCH2SO4. In optimum hydrolysis conditions, 80 °C, 1.5 h, 0.8 M Cr(NO33 metal salt and solid–liquid ratio of 1:30, the CNCCr(NO33 exhibited a network-like long fibrous structure with the aspect ratio of 15.7, while the CNCH2SO4 showed rice-shape structure with an aspect ratio of 3.5. Additionally, Cr(NO33-treated CNC rendered a higher crystallinity (86.5% ± 0.3% with high yield (83.6% ± 0.6% as compared to the H2SO4-treated CNC (81.4% ± 0.1% and 54.7% ± 0.3%, respectively. Furthermore, better thermal stability of CNCCr(NO33 (344 °C compared to CNCH2SO4 (273 °C rendered a high potential for nanocomposite application. This comparable effectiveness of Cr(NO33 metal salt provides milder hydrolysis conditions for highly selective depolymerization of cellulosic fiber into value-added cellulose nanomaterial, or useful chemicals and fuels in the future.

  12. Cellulose nanomaterials review: structure, properties and nanocomposites.

    Science.gov (United States)

    Moon, Robert J; Martini, Ashlie; Nairn, John; Simonsen, John; Youngblood, Jeff

    2011-07-01

    This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them. It summarizes cellulose nanoparticles in terms of particle morphology, crystal structure, and properties. Also described are the self-assembly and rheological properties of cellulose nanoparticle suspensions. The methodology of composite processing and resulting properties are fully covered, with an emphasis on neat and high fraction cellulose composites. Additionally, advances in predictive modeling from molecular dynamic simulations of crystalline cellulose to the continuum modeling of composites made with such particles are reviewed (392 references).

  13. Isolation and characterization of cellulose nanofibers from bamboo using microwave liquefaction combined with chemical treatment and ultrasonication.

    Science.gov (United States)

    Xie, Jiulong; Hse, Chung-Yun; De Hoop, Cornelis F; Hu, Tingxing; Qi, Jinqiu; Shupe, Todd F

    2016-10-20

    Cellulose nanofibers were successfully isolated from bamboo using microwave liquefaction combined with chemical treatment and ultrasonic nanofibrillation processes. The microwave liquefaction could eliminate almost all the lignin in bamboo, resulting in high cellulose content residues within 7min, and the cellulose enriched residues could be readily purified by subsequent chemical treatments with lower chemical charging and quickly. The results of wet chemistry analyses, SEM images, and FTIR and X-ray spectra indicated the combination of microwave liquefaction and chemical treatment was significantly efficient in removing non-cellulosic compounds. Ultrasonication was used to separate the nanofibrils from the purified residues to extract nanofibers. The TEM images confirmed the presence of elementary fibrils, nano-sized fibril bundles, and aggregated fibril bundles. As evidenced by the TGA analysis, cellulose nanofibers isolated by this novel technique had high thermal stability indicating that the isolated nanofibers could possibly be applied as reinforcing elements in biomaterials.

  14. Cellulose nanomaterials in water treatment technologies.

    Science.gov (United States)

    Carpenter, Alexis Wells; de Lannoy, Charles-François; Wiesner, Mark R

    2015-05-05

    Cellulose nanomaterials are naturally occurring with unique structural, mechanical and optical properties. While the paper and packaging, automotive, personal care, construction, and textiles industries have recognized cellulose nanomaterials' potential, we suggest cellulose nanomaterials have great untapped potential in water treatment technologies. In this review, we gather evidence of cellulose nanomaterials' beneficial role in environmental remediation and membranes for water filtration, including their high surface area-to-volume ratio, low environmental impact, high strength, functionalizability, and sustainability. We make direct comparison between cellulose nanomaterials and carbon nanotubes (CNTs) in terms of physical and chemical properties, production costs, use and disposal in order to show the potential of cellulose nanomaterials as a sustainable replacement for CNTs in water treatment technologies. Finally, we comment on the need for improved communication and collaboration across the myriad industries invested in cellulose nanomaterials production and development to achieve an efficient means to commercialization.

  15. Bioplastic production from cellulose of oil palm empty fruit bunch

    Science.gov (United States)

    Isroi; Cifriadi, A.; Panji, T.; Wibowo, Nendyo A.; Syamsu, K.

    2017-05-01

    Empty fruit bunch is available abundantly in Indonesia as side product of CPO production. EFB production in Indonesia reached 28.65 million tons in 2015. EFB consist of 36.67% cellulose, 13.50% hemicellulose and 31.16% lignin. By calculation, potential cellulose from EFB is 11.50 million tons. Cellulose could be utilized as source for bioplastic production. This research aims to develop bioplastic production based on cellulose from EFB and to increase added value of EFB. Cellulose fiber has no plastic properties. Molecular modification of cellulose, composite with plasticizer and compatibilizer is a key success for utilization of cellulose for bioplastic. Main steps of bioplastic production from EFB are: 1) isolation and purification of cellulose, 2) cellulose modification and 3) synthesis of bioplastic. Cellulose was isolated by sodium hydroxide methods and bleached using sodium hypochlorite. Purity of obtained cellulose was 97%. Cellulose yield could reach 30% depend on cellulose content of EFB. Cellulose side chain was oxidized to reduce hydroxyl group and increase the carboxyl group. Bioplastic synthesis used glycerol as plasticizer and cassava starch as matrix. This research was successfully producing bioplastic sheet by casting method. In future prospects, bioplastic from EFB cellulose can be developed as plastic bag and food packaging.

  16. [Supramolecular reorganizations in cellulose during hydration].

    Science.gov (United States)

    Grunin, Iu B; Grunin, L Iu; Talantsev, V I; Nikol'skaia, E A; Masas, D S

    2015-01-01

    The analysis of modern ideas about the structural organization of the cellulose microfibrils is carried out. The mechanism of the formation of additional capillary-porous system of cellulose under moistening is offered. It is established that when the moisture content of cellulose reaches 8-10%, the filling of its micropores occurs with a simultaneous increase in their cross sizes, a specific surface and reduction in the degree of crystallinity of specimens. Within the proposed model of microfibril construction the parameters of supramolecular structure and capillary-porous system of cotton cellulose are determined.

  17. Transcription factors for modification of lignin content in plants

    Science.gov (United States)

    Wang, Huanzhong; Chen, Fang; Dixon, Richard A.

    2015-06-02

    The invention provides methods for modifying lignin, cellulose, xylan, and hemicellulose content in plants, and for achieving ectopic lignification and, for instance, secondary cell wall synthesis in pith cells, by altered regulation of a WRKY transcription factor. Nucleic acid constructs for altered WRKY-TF expression are described. Transgenic plants are provided that comprise modified pith cell walls, and lignin, cellulose, and hemicellulose content. Plants described herein may be used, for example, as improved biofuel feedstock and as highly digestible forage crops.

  18. Transcription factors for modification of lignin content in plants

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huanzhong; Chen, Fang; Dixon, Richard A.

    2015-06-02

    The invention provides methods for modifying lignin, cellulose, xylan, and hemicellulose content in plants, and for achieving ectopic lignification and, for instance, secondary cell wall synthesis in pith cells, by altered regulation of a WRKY transcription factor. Nucleic acid constructs for altered WRKY-TF expression are described. Transgenic plants are provided that comprise modified pith cell walls, and lignin, cellulose, and hemicellulose content. Plants described herein may be used, for example, as improved biofuel feedstock and as highly digestible forage crops.

  19. Densidade básica do colmo e fibras celulósicas em progênies de Bambusa tuldoides Munro Basic density and cellulosic fiber content in Bambusa tuldoides progenies

    Directory of Open Access Journals (Sweden)

    Anisio Azzini

    1988-01-01

    Full Text Available Na espécie Bambusa tuldoides em vinte e uma progênies, determinou-se a densidade básica do colmo, o rendimento em fibras celulósicas e as dimensões destas. A densidade básica variou acentuadamente de 0,407 a 0,712g/cm³, evidenciando alterações nas características químicas e anatômicas dos colmos. As variações nos rendimentos em fibras celulósicas - 45,67 a 56,78% - não foram significativas, sugerindo que a quantidade de fibras no colmo pouco influi em sua densidade básica. Esta característica foi influenciada pelo diâmetro de lúmen das fibras, sendo o maior lúmen (4,86 microns responsável pela menor densidade básica (0,407g/cm³. O comprimento médio das fibras celulósicas da espécie Bambusa tuldoides (1,97mm e suas progênies (1,49 a 3,17mm ocupou uma posição intermediária entre fibras de eucalipto (1,0mm e pínus (3,5mm. Em função do comprimento das fibras, foi possível selecionar as progênies P.5 (3,17mm, P.11 (2,41 mm e P.13 (2,61 mm como fornecedoras de fibras longas.Basic density of the culm, the cellulosic fiber content and fiber dimensions were determined in twenty-one progenies of Bambusa tuldoides Munro, and in the typical species as controls. High variation in the basic density (from 0.407 to 0.712g/cm³ was observed, denoting some chemical and anatomical modifications in the culm. The cellulosic fiber content (45.67 to 56.78% varied less markedly, suggesting that the culm fiber content did not influence the basic density. This characteristic depends on the cell cavity diameter. The smallest value for basic density (0.407g/cm³ was obtained for the highest cell cavity diameter. The average fiber length of Bambusa tuldoides (1.97mm and its progenies (1.49 to 3.17mm is situated in intermediate position between those of Eucaliptus (1.0mm and Pinus (3.5mm. It was possible to recognize the progenies P.5, P.11 and P.13, with long fibers, respectively with 3.17, 2.41 and 2.61mm.

  20. Magnetic poly(lactide-co-glycolide) (PLGA) and cellulose particles for MRI-based cell tracking

    Science.gov (United States)

    Nkansah, Michael K.; Thakral, Durga; Shapiro, Erik M.

    2010-01-01

    Biodegradable, superparamagnetic micro- and nanoparticles of poly(lactide-co-glycolide) (PLGA) and cellulose were designed, fabricated and characterized for magnetic cell labeling. Monodisperse nanocrystals of magnetite were incorporated into micro- and nanoparticles of PLGA and cellulose with high efficiency using an oil-in-water single emulsion technique. Superparamagnetic cores had high magnetization (72.1 emu/g). The resulting polymeric particles had smooth surface morphology and high magnetite content (43.3 wt% for PLGA and 69.6 wt% for cellulose). While PLGA and cellulose nanoparticles displayed highest r2* values per millimole of iron (399 s-1mM-1 for cellulose and 505 s-1mM-1 for PLGA), micron-sized PLGA particles had a much higher r2* per particle than either. After incubation for a month in citrate buffer (pH 5.5), magnetic PLGA particles lost close to 50% of their initial r2* molar relaxivity, while magnetic cellulose particles remained intact, preserving over 85% of their initial r2* molar relaxivity. Lastly, mesenchymal stem cells and human breast adenocarcinoma cells were magnetically labeled using these particles with no detectable cytotoxicity. These particles are ideally suited for non-invasive cell tracking in vivo via MRI and due to their vastly different degradation properties, offer unique potential for dedicated use for either short (PLGA-based particles) or long term (cellulose-based particles) experiments. PMID:21404328

  1. Magnetic poly(lactide-co-glycolide) and cellulose particles for MRI-based cell tracking.

    Science.gov (United States)

    Nkansah, Michael K; Thakral, Durga; Shapiro, Erik M

    2011-06-01

    Biodegradable, superparamagnetic microparticles and nanoparticles of poly(lactide-co-glycolide) (PLGA) and cellulose were designed, fabricated, and characterized for magnetic cell labeling. Monodisperse nanocrystals of magnetite were incorporated into microparticles and nanoparticles of PLGA and cellulose with high efficiency using an oil-in-water single emulsion technique. Superparamagnetic cores had high magnetization (72.1 emu/g). The resulting polymeric particles had smooth surface morphology and high magnetite content (43.3 wt % for PLGA and 69.6 wt % for cellulose). While PLGA and cellulose nanoparticles displayed highest r 2* values per millimole of iron (399 sec(-1) mM(-1) for cellulose and 505 sec(-1) mM(-1) for PLGA), micron-sized PLGA particles had a much higher r 2* per particle than either. After incubation for a month in citrate buffer (pH 5.5), magnetic PLGA particles lost close to 50% of their initial r 2* molar relaxivity, while magnetic cellulose particles remained intact, preserving over 85% of their initial r 2* molar relaxivity. Lastly, mesenchymal stem cells and human breast adenocarcinoma cells were magnetically labeled using these particles with no detectable cytotoxicity. These particles are ideally suited for noninvasive cell tracking in vivo via MRI and due to their vastly different degradation properties, offer unique potential for dedicated use for either short (PLGA-based particles) or long-term (cellulose-based particles) experiments.

  2. One-Pot Route towards Active TiO2 Doped Hierarchically Porous Cellulose: Highly Efficient Photocatalysts for Methylene Blue Degradation

    Directory of Open Access Journals (Sweden)

    Xiaoxia Sun

    2017-03-01

    Full Text Available In this study, novel photocatalyst monolith materials were successfully fabricated by a non-solvent induced phase separation (NIPS technique. By adding a certain amount of ethyl acetate (as non-solvent into a cellulose/LiCl/N,N-dimethylacetamide (DMAc solution, and successively adding titanium dioxide (TiO2 nanoparticles (NPs, cellulose/TiO2 composite monoliths with hierarchically porous structures were easily formed. The obtained composite monoliths possessed mesopores, and two kinds of macropores. Scanning Electron Microscope (SEM, Energy Dispersive Spectroscopy (EDS, Fourier Transform Infrared Spectroscopy (FT-IR, X-ray Diffraction (XRD, Brunauer-Emmett-Teller (BET, and Ultraviolet-visible Spectroscopy (UV-Vis measurements were adopted to characterize the cellulose/TiO2 composite monolith. The cellulose/TiO2 composite monoliths showed high efficiency of photocatalytic activity in the decomposition of methylene blue dye, which was decomposed up to 99% within 60 min under UV light. Moreover, the composite monoliths could retain 90% of the photodegradation efficiency after 10 cycles. The novel NIPS technique has great potential for fabricating recyclable photocatalysts with highly efficiency.

  3. Comparing oxidative and dilute acid wet explosion pretreatment of Cocksfoot grass at high dry matter concentration for cellulosic ethanol production

    DEFF Research Database (Denmark)

    Njoku, Stephen Ikechukwu; Uellendahl, Hinrich; Ahring, Birgitte Kiær

    2013-01-01

    was investigated for cellulosic ethanol production. The biomass raw materials were pretreated using wet explosion (WEx) at 25% dry matter concentration with addition of oxygen or dilute sulfuric acid. The enzymatic hydrolysis of cellulose was significantly improved after pretreatment. The highest conversion...... into cellulose monomeric C6 sugars was achieved for WEx condition AC-E (180°C, 15 min, and 0.2% sulfuric acid). For that condition, the highest ethanol yield of 197 g/kg DM (97% of theoretical maximum value) was achieved for SSF process by Saccharomyces cerevisiae. However, the highest concentration...

  4. Oxidizing Cellulose to 2,3-Dialdehyde Cellulose by Sodium Periodate

    Institute of Scientific and Technical Information of China (English)

    MENG Shuxian; FENG Yaqing; LIANG Zupei; FU Qiang; ZHANG Enzhong

    2005-01-01

    Study on oxidizing cellulose to 2,3-dialdehyde cellulose by sodium periodate (NaIO4) was carried out. The effects of reaction conditions such as pH of solution, temperature, oxidant concentration, oxidation time, the particle size of 2,3-dialdehyde cellulose and alkali treatment temperature on the dialdehyde concentration of cellulose were investigated in detail. The results show that the aldehyde group content was created while reaction temperature and alkali treatment temperature increased.The most principal factors affecting the aldehyde group content of 2,3-dialdehyde cellulose were found out and the best oxidation conditions were as follows: the pH was 2, the reaction temperature was 45 ℃, the mass ratio of cellulose to NaIO4 was 1/2, the reaction time was 4 h, the alkali treatment temperature was 70 ℃ and smaller particle size was 0.80 mm.

  5. Cellulose nanofibril/reduced graphene oxide/carbon nanotube hybrid aerogels for highly flexible and all-solid-state supercapacitors.

    Science.gov (United States)

    Zheng, Qifeng; Cai, Zhiyong; Ma, Zhenqiang; Gong, Shaoqin

    2015-02-11

    A novel type of highly flexible and all-solid-state supercapacitor that uses cellulose nanofibril (CNF)/reduced graphene oxide (RGO)/carbon nanotube (CNT) hybrid aerogels as electrodes and H2SO4/poly(vinyl alcohol) (PVA) gel as the electrolyte was developed and is reported here. These flexible solid-state supercapacitors were fabricated without any binders, current collectors, or electroactive additives. Because of the porous structure of the CNF/RGO/CNT aerogel electrodes and the excellent electrolyte absorption properties of the CNFs present in the aerogel electrodes, the resulting flexible supercapacitors exhibited a high specific capacitance (i.e., 252 F g(-1) at a discharge current density of 0.5 A g(-1)) and a remarkable cycle stability (i.e., more than 99.5% of the capacitance was retained after 1000 charge-discharge cycles at a current density of 1 A g(-1)). Furthermore, the supercapacitors also showed extremely high areal capacitance, areal power density, and energy density (i.e., 216 mF cm(-2), 9.5 mW cm(-2), and 28.4 μWh cm(-2), respectively). In light of its excellent electrical performance, low cost, ease of large-scale manufacturing, and environmental friendliness, the CNF/RGO/CNT aerogel electrodes may have a promising application in the development of flexible energy-storage devices.

  6. Modulation of the cellulose content of tuber cell walls by antisense expression of different potato (Solanum tuberosum L.) CesA clones

    NARCIS (Netherlands)

    Oomen, R.J.F.J.; Tzitzikas, E.; Bakx, E.J.; Straatman-Engelen, I.; Bush, M.S.; Mccann, M.C.; Schols, H.A.; Visser, R.G.F.; Vincken, J.P.

    2004-01-01

    Four potato cellulose synthase (CesA) homologs (StCesA1, 2, 3 and 4) were isolated by screening a cDNA library made from developing tubers. Based on sequence comparisons and the fact that all four potato cDNAs were isolated from this single cDNA-library, all four StCesA clones are likely to play a r

  7. Cellulose Insulation

    Science.gov (United States)

    1980-01-01

    Fire retardant cellulose insulation is produced by shredding old newspapers and treating them with a combination of chemicals. Insulating material is blown into walls and attics to form a fiber layer which blocks the flow of air. All-Weather Insulation's founders asked NASA/UK-TAP to help. They wanted to know what chemicals added to newspaper would produce an insulating material capable of meeting federal specifications. TAP researched the query and furnished extensive information. The information contributed to successful development of the product and helped launch a small business enterprise which is now growing rapidly.

  8. Shedding light on filovirus infection with high-content imaging.

    Science.gov (United States)

    Pegoraro, Gianluca; Bavari, Sina; Panchal, Rekha G

    2012-08-01

    Microscopy has been instrumental in the discovery and characterization of microorganisms. Major advances in high-throughput fluorescence microscopy and automated, high-content image analysis tools are paving the way to the systematic and quantitative study of the molecular properties of cellular systems, both at the population and at the single-cell level. High-Content Imaging (HCI) has been used to characterize host-virus interactions in genome-wide reverse genetic screens and to identify novel cellular factors implicated in the binding, entry, replication and egress of several pathogenic viruses. Here we present an overview of the most significant applications of HCI in the context of the cell biology of filovirus infection. HCI assays have been recently implemented to quantitatively study filoviruses in cell culture, employing either infectious viruses in a BSL-4 environment or surrogate genetic systems in a BSL-2 environment. These assays are becoming instrumental for small molecule and siRNA screens aimed at the discovery of both cellular therapeutic targets and of compounds with anti-viral properties. We discuss the current practical constraints limiting the implementation of high-throughput biology in a BSL-4 environment, and propose possible solutions to safely perform high-content, high-throughput filovirus infection assays. Finally, we discuss possible novel applications of HCI in the context of filovirus research with particular emphasis on the identification of possible cellular biomarkers of virus infection.

  9. Shedding Light on Filovirus Infection with High-Content Imaging

    Directory of Open Access Journals (Sweden)

    Rekha G. Panchal

    2012-08-01

    Full Text Available Microscopy has been instrumental in the discovery and characterization of microorganisms. Major advances in high-throughput fluorescence microscopy and automated, high-content image analysis tools are paving the way to the systematic and quantitative study of the molecular properties of cellular systems, both at the population and at the single-cell level. High-Content Imaging (HCI has been used to characterize host-virus interactions in genome-wide reverse genetic screens and to identify novel cellular factors implicated in the binding, entry, replication and egress of several pathogenic viruses. Here we present an overview of the most significant applications of HCI in the context of the cell biology of filovirus infection. HCI assays have been recently implemented to quantitatively study filoviruses in cell culture, employing either infectious viruses in a BSL-4 environment or surrogate genetic systems in a BSL-2 environment. These assays are becoming instrumental for small molecule and siRNA screens aimed at the discovery of both cellular therapeutic targets and of compounds with anti-viral properties. We discuss the current practical constraints limiting the implementation of high-throughput biology in a BSL-4 environment, and propose possible solutions to safely perform high-content, high-throughput filovirus infection assays. Finally, we discuss possible novel applications of HCI in the context of filovirus research with particular emphasis on the identification of possible cellular biomarkers of virus infection.

  10. Grafted cellulose for PAHs removal present in industrial discharge waters

    Science.gov (United States)

    Euvrard, Elise; Druart, Coline; Poupeney, Amandine; Crini, Nadia; Vismara, Elena; Lanza, Tommaso; Torri, Giangiacomo; Gavoille, Sophie; Crini, Gregorio

    2014-05-01

    , the grafted cellulose showed lower adsorption capacities of PAHs (about 40% for the total PAH content) when they were in real effluents than they were in synthetic solutions. However, it was observed that PAH composition in discharge waters was different than in synthetic solutions, qualitatively and quantitatively. Despite the presence of numerous other substances in industrial effluents at high concentrations (for instance metals equal to mg/L and salts to g/L), the grafted cellulose was demonstrated as suitable to remove organic substances at trace levels like PAHs (equal to ng/L). Reference: [1] Vismara E., Melone L., Gastaldi G., Cosentino C., Torri G. J. Hazardous Mat. 170 (2009) 798-808. Acknowledgements: The authors thank Agence de l'Eau, FEDER and the Conseil regional de Franche-Comté for financial support (NIRHOFEX Program).

  11. Two stage hydrolysis of corn stover at high solids content for mixing power saving and scale-up applications.

    Science.gov (United States)

    Liu, Ke; Zhang, Jian; Bao, Jie

    2015-11-01

    A two stage hydrolysis of corn stover was designed to solve the difficulties between sufficient mixing at high solids content and high power input encountered in large scale bioreactors. The process starts with the quick liquefaction to convert solid cellulose to liquid slurry with strong mixing in small reactors, then followed the comprehensive hydrolysis to complete saccharification into fermentable sugars in large reactors without agitation apparatus. 60% of the mixing energy consumption was saved by removing the mixing apparatus in large scale vessels. Scale-up ratio was small for the first step hydrolysis reactors because of the reduced reactor volume. For large saccharification reactors in the second step, the scale-up was easy because of no mixing mechanism was involved. This two stage hydrolysis is applicable for either simple hydrolysis or combined fermentation processes. The method provided a practical process option for industrial scale biorefinery processing of lignocellulose biomass. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. EFFECT OF CARBON CONTENT ON MICROSTRUCTURE AND PROPERTIES OF HIGH STRENGTH AND HIGH ELONGATION STEELS

    Institute of Scientific and Technical Information of China (English)

    Y.Chen; X.Chen; 等

    2003-01-01

    The microstructure and mechanical properties of new kind of hot-rolled high strength and high elongation steels with retained austenite were studied by discussing the in-fluence of different carbon content.The research results indicate that carbon content has a significant effect on retaining austenite and consequently resulting in high elon-gation.Besides,new findings about relationship between carbon content and retained austenite as well as properties were discussed in the paper.

  13. Radiation pretreatment of cellulose for energy production

    Science.gov (United States)

    Dela Rosa, A. M.; Dela Mines, A. S.; Banzon, R. B.; Simbul-Nuguid, Z. F.

    The effect of radiation pretreatment of agricultural cellulosic wastes was investigated through hydrolytic reactions of cellulose. Gamma irradiation significantly increased the acid hydrolysis of rice straw, rice hull and corn husk. The yields of reducing sugar were higher with increasing radiation dose in these materials. The observed radiation effect varied with the cellulosic material but it correlated with neither the cellulose content nor the lignin content. Likewise, the radiation pretreatment accelerated the subsequent enzymatic hydrolysis of rice straw and rice hull by cellulase. The irradiated rice straw appeared to be a better growth medium for the cellulolytic microorganism, Myrothecium verrucaria, than the non-irradiated material. This was attributed to increased digestibility of the cellulose by the microorganism.

  14. Evaluation of dissolution rate on high plutonium content MOX fuel

    Energy Technology Data Exchange (ETDEWEB)

    Sugaya, Shinichi; Kurita, Ichiro; Endo, Hideo; Higuchi, Hidetoshi; Kihara, Yoshiyuki [Japan Nuclear Cycle Development Inst., Tokai Works, Tokai, Ibaraki (Japan); Ogasawara, Masahiro; Shinada, Masanori; Kowata, Masato [Inspection Development Company Ltd., Tokai, Ibaraki (Japan)

    2002-06-01

    The dissolution rate of high Pu content MOX fuel into nitric acid was measured as a function of Pu content. MOX fuel samples, pressed and sintered, were dissolved in 7 M of boiling nitric acid, and the dissolution rate was measured by analyzing the Pu and U concentration in the solution. The dissolution rate of MOX fuel tended to decrease with the increase in the Pu content and was reduced after 6 hours of dissolution. These results agreed well with previous ones, but the dissolution rate was 3-6 times faster than those. It is estimated that the cause of this difference was due to underestimation of the surface area of MOX fuel powder and the difference of the MOX O/M ratio. (author)

  15. Developmental toxicity assay using high content screening of zebrafish embryos.

    Science.gov (United States)

    Lantz-McPeak, Susan; Guo, Xiaoqing; Cuevas, Elvis; Dumas, Melanie; Newport, Glenn D; Ali, Syed F; Paule, Merle G; Kanungo, Jyotshna

    2015-03-01

    Typically, time-consuming standard toxicological assays using the zebrafish (Danio rerio) embryo model evaluate mortality and teratogenicity after exposure during the first 2 days post-fertilization. Here we describe an automated image-based high content screening (HCS) assay to identify the teratogenic/embryotoxic potential of compounds in zebrafish embryos in vivo. Automated image acquisition was performed using a high content microscope system. Further automated analysis of embryo length, as a statistically quantifiable endpoint of toxicity, was performed on images post-acquisition. The biological effects of ethanol, nicotine, ketamine, caffeine, dimethyl sulfoxide and temperature on zebrafish embryos were assessed. This automated developmental toxicity assay, based on a growth-retardation endpoint should be suitable for evaluating the effects of potential teratogens and developmental toxicants in a high throughput manner. This approach can significantly expedite the screening of potential teratogens and developmental toxicants, thereby improving the current risk assessment process by decreasing analysis time and required resources.

  16. Highly Anisotropic Thermal Conductivity of Layer-by-Layer Assembled Nanofibrillated Cellulose/Graphene Nanosheets Hybrid Films for Thermal Management.

    Science.gov (United States)

    Song, Na; Jiao, Dejin; Cui, Siqi; Hou, Xingshuang; Ding, Peng; Shi, Liyi

    2017-01-25

    An anisotropic thermally conductive film with tailorable microstructures and macroproperties is fabricated using a layer-by-layer (LbL) assembly of graphene oxide (GO) and nanofibrillated cellulose (NFC) on a flexible NFC substrate driven by hydrogen bonding interactions, followed by chemical reduction process. The resulting NFC/reduced graphene oxide (RGO) hybrid film reveals an orderly hierarchical structure in which the RGO nanosheets exhibit a high degree of orientation along the in-plane direction. The assembly cycles dramatically increase the in-plane thermal conductivity (λX) of the hybrid film to 12.6 W·m(-1)·K(-1), while the cross-plane thermal conductivity (λZ) shows a lower value of 0.042 W·m(-1)·K(-1) in the hybrid film with 40 assembly cycles. The thermal conductivity anisotropy reaches up to λX/λZ = 279, which is substantially larger than that of similar polymeric nanocomposites, indicating that the LbL assembly on a flexible NFC substrate is an efficient technique for the preparation of polymeric nanocomposites with improved heat conducting property. Moreover, the layered hybrid film composed of 1D NFC and 2D RGO exhibits synergetic mechnical properties with outstanding flexibility and a high tensile strength (107 MPa). The combination of anisotropic thermal conductivity and superior mechanical performance may facilitate the applications in thermal management.

  17. Nano-gold assisted highly conducting and biocompatible bacterial cellulose-PEDOT:PSS films for biology-device interface applications.

    Science.gov (United States)

    Khan, Shaukat; Ul-Islam, Mazhar; Ullah, Muhammad Wajid; Israr, Muhammad; Jang, Jae Hyun; Park, Joong Kon

    2017-09-18

    This study reports the fabrication of highly conducting and biocompatible bacterial cellulose (BC)-gold nanoparticles (AuNPs)-poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) (BC-AuNPs-PEDOT:PSS) composites for biology-device interface applications. The composites were fabricated using ex situ incorporation of AuNPs and PEDOT:PSS into the BC matrix. Structural characterization, using scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and x-ray diffraction (XRD) analysis, confirmed the uniform nature of the synthesized BC-AuNPs and BC-AuNPs-PEDOT:PSS composites. Four-point probe analysis indicated that the BC-AuNPs and BC-AuNPs-PEDOT:PSS films had high electrical conductivity. The composites were also tested for biocompatibility with animal osteoblasts (MC3T3-E1). The composite films supported adhesion, growth, and proliferation of MC3T3-E1 cells, indicating that they are biocompatible and non-cytotoxic. AuNPs and PEDOT:PSS, imparted a voltage response, while BC imparted biocompatibility and bio-adhesion to the nanocomposites. Therefore, our BC-AuNPs-PEDOT:PSS composites are candidate materials for biology-device interfaces to produce implantable devices in regenerative medicine. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Highly thermostable and pH-stable cellulases from Aspergillus niger NS-2: properties and application for cellulose hydrolysis.

    Science.gov (United States)

    Bansal, Namita; Janveja, Chetna; Tewari, Rupinder; Soni, Raman; Soni, Sanjeev Kumar

    2014-01-01

    Optimization of cultural conditions for enhanced cellulase production by Aspergillus niger NS-2 were studied under solid-state fermentation. Significant increase in yields (CMCase 463.9 ± 20.1 U/g, FPase 101.1 ± 3.5 U/g and β-glucosidase 99 ± 4.0 U/g) were obtained under optimized conditions. Effect of different nutritional parameters was studied to induce the maximum production of cellulase complex. Scale-up studies for enzyme production process were carried out. Characterization studies showed that enzymes produced by A. niger NS-2 were highly temperature- and pH stable. At 50 °C, the half life for CMCase, FPase, β-glucosidase were approximately 240 h. Cellulases from A. niger NS-2 were stable at 35 °C for 24 h over a broader pH range of 3.0-9.0. We examined the feasibility of using steam pretreatment to increase the saccharification yields from various lignocellulosic residues for sugar release which can potentially be used in bioethanol production. Saccharification of pretreated dry potato peels, carrot peels, composite waste mixture, orange peels, onion peels, banana peels, pineapple peels by crude enzyme extract from A. niger NS-2, resulted in very high cellulose conversion efficiencies of 92-98 %.

  19. A process for energy-efficient high-solids fed-batch enzymatic liquefaction of cellulosic biomass.

    Science.gov (United States)

    Cardona, M J; Tozzi, E J; Karuna, N; Jeoh, T; Powell, R L; McCarthy, M J

    2015-12-01

    The enzymatic hydrolysis of cellulosic biomass is a key step in the biochemical production of fuels and chemicals. Economically feasible large-scale implementation of the process requires operation at high solids loadings, i.e., biomass concentrations >15% (w/w). At increasing solids loadings, however, biomass forms a high viscosity slurry that becomes increasingly challenging to mix and severely mass transfer limited, which limits further addition of solids. To overcome these limitations, we developed a fed-batch process controlled by the yield stress and its changes during liquefaction of the reaction mixture. The process control relies on an in-line, non-invasive magnetic resonance imaging (MRI) rheometer to monitor real-time evolution of yield stress during liquefaction. Additionally, we demonstrate that timing of enzyme addition relative to biomass addition influences process efficiency, and the upper limit of solids loading is ultimately limited by end-product inhibition as soluble glucose and cellobiose accumulate in the liquid phase. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Porous cellulose diacetate-SiO2 composite coating on polyethylene separator for high-performance lithium-ion battery.

    Science.gov (United States)

    Chen, Wenju; Shi, Liyi; Wang, Zhuyi; Zhu, Jiefang; Yang, Haijun; Mao, Xufeng; Chi, Mingming; Sun, Lining; Yuan, Shuai

    2016-08-20

    The developments of high-performance lithium ion battery are eager to the separators with high ionic conductivity and thermal stability. In this work, a new way to adjust the comprehensive properties of inorganic-organic composite separator was investigated. The cellulose diacetate (CDA)-SiO2 composite coating is beneficial for improving the electrolyte wettability and the thermal stability of separators. Interestingly, the pore structure of composite coating can be regulated by the weight ratio of SiO2 precursor tetraethoxysilane (TEOS) in the coating solution. The electronic performance of lithium ion batteries assembled with modified separators are improved compared with the pristine PE separator. When weight ratio of TEOS in the coating solution was 9.4%, the composite separator shows the best comprehensive performance. Compared with the pristine PE separator, its meltdown temperature and the break-elongation at elevated temperature increased. More importantly, the discharge capacity and the capacity retention improved significantly. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Taichi-inspired rigid-flexible coupling cellulose-supported solid polymer electrolyte for high-performance lithium batteries.

    Science.gov (United States)

    Zhang, Jianjun; Yue, Liping; Hu, Pu; Liu, Zhihong; Qin, Bingsheng; Zhang, Bo; Wang, Qingfu; Ding, Guoliang; Zhang, Chuanjian; Zhou, Xinhong; Yao, Jianhua; Cui, Guanglei; Chen, Liquan

    2014-09-03

    Inspired by Taichi, we proposed rigid-flexible coupling concept and herein developed a highly promising solid polymer electrolyte comprised of poly (ethylene oxide), poly (cyano acrylate), lithium bis(oxalate)borate and robust cellulose nonwoven. Our investigation revealed that this new class solid polymer electrolyte possessed comprehensive properties in high mechanical integrity strength, sufficient ionic conductivity (3 × 10(-4) S cm(-1)) at 60°C and improved dimensional thermostability (up to 160°C). In addition, the lithium iron phosphate (LiFePO4)/lithium (Li) cell using such solid polymer electrolyte displayed superior rate capacity (up to 6 C) and stable cycle performance at 80°C. Furthermore, the LiFePO4/Li battery could also operate very well even at an elevated temperature of 160°C, thus improving enhanced safety performance of lithium batteries. The use of this solid polymer electrolyte mitigates the safety risk and widens the operation temperature range of lithium batteries. Thus, this fascinating study demonstrates a proof of concept of the use of rigid-flexible coupling solid polymer electrolyte toward practical lithium battery applications with improved reliability and safety.

  2. Synthesis of superhydrophobic ultralight aerogels from nanofibrillated cellulose isolated from natural reed for high-performance adsorbents

    Science.gov (United States)

    Jiao, Yue; Wan, Caichao; Qiang, Tiangang; Li, Jian

    2016-07-01

    Reed is one of the widely available aquatic plant resources, and its applications are generally limited to some traditional areas like papermaking and animals' fodder. Besides, most of reed is wasted or directly burned every year causing serious air pollution (like atmospheric haze). Therefore, it is worth to further develop new forms of high-value applications of reed. Herein, natural reed was collected to fabricate ultralight adsorbents namely nanofibrillated cellulose (NFC) aerogels via an easily operated method, which includes chemical purification, ultrasonication, and freeze drying. The NFC aerogels with an ultra-low density of 4.9 mg cm-3 were characterized by scanning electron microscopy, energy-dispersive X-ray spectrometer, Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis. For acquiring good hydrophobicity, the NFC aerogels were subjected to a hydrophobic treatment by methyltrichlorosilane. The superhydrophobic NFC aerogels with contact angles of as high as 151°-155° have excellent adsorption efficiency (53-93 g g-1) for various organic solvents and waste oil. More importantly, the aerogels also exhibit favorable adsorption recyclability, which can maintain more than 80 % of the initial adsorption efficiency after the five cycles.

  3. Mechanical Properties of Cellulose Microfiber Reinforced Polyolefin

    Science.gov (United States)

    Kobayashi, Satoshi; Yamada, Hiroyuki

    Cellulose microfiber (CeF) has been expected as a reinforcement of polymer because of its high modulus and strength and lower cost. In the present study, mechanical properties of CeF/polyolefin were investigated. Tensile modulus increased with increasing CeF content. On the other hand, tensile strength decreased. Fatigue properties were also investigated with acoustic emission measurement. Stiffness of the composites gradually decreased with loading. Drastic decrease in stiffness was observed just before the final fracture. Based on the Mori-Tanaka's theory, the method to calculate modulus of CeF were proposed to evaluate dispersion of CeF.

  4. Molecular Dynamics of Materials Possessing High Energy Content.

    Science.gov (United States)

    1988-01-26

    I -RI90 634 MOLECULAR DYNAMICS OF MATERIALS POSSESSING HIGH ENERGY 1/1 r CONTENTCU) COLUMBIA UNIV MENd YORK N J TURRO 26 JAN GO I RFOSR-TR-88-0168...Bolling Air Force Base, D.C. 2 61102F_ 2303 I B2 11 T,TL.E (Inciuoe Security Classification) Molecular Dynamics of Materials Possessing High Energy...York 10027 (212) 280-2175 TITLE: MOLECULAR DYNAMICS OF MATERIALS POSSESSING HIGH ENERGY CONTENT .. 0 0 88 2 ... "" ’% ,i u , . .. .. ....... ŝ" ;! ,i

  5. Information management for high content live cell imaging

    Directory of Open Access Journals (Sweden)

    White Michael RH

    2009-07-01

    Full Text Available Abstract Background High content live cell imaging experiments are able to track the cellular localisation of labelled proteins in multiple live cells over a time course. Experiments using high content live cell imaging will generate multiple large datasets that are often stored in an ad-hoc manner. This hinders identification of previously gathered data that may be relevant to current analyses. Whilst solutions exist for managing image data, they are primarily concerned with storage and retrieval of the images themselves and not the data derived from the images. There is therefore a requirement for an information management solution that facilitates the indexing of experimental metadata and results of high content live cell imaging experiments. Results We have designed and implemented a data model and information management solution for the data gathered through high content live cell imaging experiments. Many of the experiments to be stored measure the translocation of fluorescently labelled proteins from cytoplasm to nucleus in individual cells. The functionality of this database has been enhanced by the addition of an algorithm that automatically annotates results of these experiments with the timings of translocations and periods of any oscillatory translocations as they are uploaded to the repository. Testing has shown the algorithm to perform well with a variety of previously unseen data. Conclusion Our repository is a fully functional example of how high throughput imaging data may be effectively indexed and managed to address the requirements of end users. By implementing the automated analysis of experimental results, we have provided a clear impetus for individuals to ensure that their data forms part of that which is stored in the repository. Although focused on imaging, the solution provided is sufficiently generic to be applied to other functional proteomics and genomics experiments. The software is available from: fhttp://code.google.com/p/livecellim/

  6. Effect of [Emim]Ac pretreatment on the structure and enzymatic hydrolysis of sugarcane bagasse cellulose.

    Science.gov (United States)

    Bian, Jing; Peng, Feng; Peng, Xiao-Peng; Xiao, Xiao; Peng, Pai; Xu, Feng; Sun, Run-Cang

    2014-01-16

    Effect of ionic liquid pretreatment on enzymatic hydrolysis of cellulose was investigated in terms of the changes in the chemical and physical structure of the preparation. In this case, original cellulose isolated from sugarcane bagasse was subjected to ionic liquid ([Emim]Ac) dissolution at a mild temperature (90 °C) followed by regeneration in water and subsequently hydrolyzed by commercial cellulases. The original and regenerated cellulose were thoroughly characterized by XRD, FT-IR, CP/MAS (13)C NMR, and SEM. It was found that the original cellulose experienced an increase in glucose content from 80.0-83.3% to 91.6-92.8%, a decrease in the degree of polymerization from 974-1039 to 511-521, a crystal transformation from cellulose I to cellulose II, as well as an increase of surface area during the pretreatment. The results suggested that pretreatment led to effective disruption of cellulose for subsequent enzyme hydrolysis as evidenced by a high glucose conversion yield of 95.2%. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Ectopic lignification in primary cellulose-deficient cell walls of maize cell suspension cultures

    Institute of Scientific and Technical Information of China (English)

    Hugo Melida; Antonio Encina; Asier Largo-Gosens; Esther Novo-Uzal; Rogelio Santiago; Federico Pomar; Pedro Garca; Penelope Garca-Angulo; Jose Luis Acebes; Jesus Alvarez

    2015-01-01

    Maize (Zea mays L.) suspension-cultured cells with up to 70% less cellulose were obtained by stepwise habituation to dichlobenil (DCB), a cellulose biosynthesis inhibitor. Cellulose deficiency was accompanied by marked changes in cell wall matrix polysaccharides and phenolics as revealed by Fourier transform infrared (FTIR) spectroscopy. Cell wall compositional analysis indicated that the cellulose-deficient cell walls showed an enhancement of highly branched and cross-linked arabinoxylans, as well as an increased content in ferulic acid, diferulates and p-coumaric acid, and the presence of a polymer that stained positive for phloroglucinol. In accordance with this, cellulose-deficient cell walls showed a fivefold increase in Klason-type lignin. Thioacidolysis/GC-MS analysis of cellulose-deficient cell walls indicated the presence of a lignin-like polymer with a Syringyl/Guaiacyl ratio of 1.45, which differed from the sensu stricto stress-related lignin that arose in response to short-term DCB-treatments. Gene expression analysis of these cells indicated an overexpression of genes specific for the biosynthesis of monolignol units of lignin. A study of stress signaling pathways revealed an overexpression of some of the jasmonate signaling pathway genes, which might trigger ectopic lignification in response to cell wall integrity disruptions. In summary, the structural plasticity of primary cell walls is proven, since a lignification process is possible in response to cellulose impoverishment.

  8. Aggressive content of high school students' TV viewing.

    Science.gov (United States)

    Yoon, Jina S; Somers, Cheryl L

    2003-12-01

    The purpose of this study was to examine high school students' exposure to television programming with aggressive content and to explore whether consumption of aggressive TV varied by sex and ethnicity. Participants were 472 boys and girls from two high schools, one urban and one suburban. Definitions of both direct and indirect aggression were used to rate TV programs, and the participants' exposure to both was assessed. Analysis yielded a statistically significant effect for sex but not ethnicity as girls watched more TV programs containing indirect aggression. Also, exposure to aggressive TV content peaked in Grade 10 and fell sharply thereafter. The importance of educating adolescents about the images they view is highlighted. Implications for research are discussed.

  9. Method for creating high carbon content products from biomass oil

    Science.gov (United States)

    Parker, Reginald; Seames, Wayne

    2012-12-18

    In a method for producing high carbon content products from biomass, a biomass oil is added to a cracking reactor vessel. The biomass oil is heated to a temperature ranging from about 100.degree. C. to about 800.degree. C. at a pressure ranging from about vacuum conditions to about 20,700 kPa for a time sufficient to crack the biomass oil. Tar is separated from the cracked biomass oil. The tar is heated to a temperature ranging from about 200.degree. C. to about 1500.degree. C. at a pressure ranging from about vacuum conditions to about 20,700 kPa for a time sufficient to reduce the tar to a high carbon content product containing at least about 50% carbon by weight.

  10. Nanostructured bacterial cellulose-poly(4-styrene sulfonic acid) composite membranes with high storage modulus and protonic conductivity.

    Science.gov (United States)

    Gadim, Tiago D O; Figueiredo, Andrea G P R; Rosero-Navarro, Nataly C; Vilela, Carla; Gamelas, José A F; Barros-Timmons, Ana; Neto, Carlos Pascoal; Silvestre, Armando J D; Freire, Carmen S R; Figueiredo, Filipe M L

    2014-05-28

    The present study reports the development of a new generation of bio-based nanocomposite proton exchange membranes based on bacterial cellulose (BC) and poly(4-styrene sulfonic acid) (PSSA), produced by in situ free radical polymerization of sodium 4-styrenesulfonate using poly(ethylene glycol) diacrylate (PEGDA) as cross-linker, followed by conversion of the ensuing polymer into the acidic form. The BC nanofibrilar network endows the composite membranes with excellent mechanical properties at least up to 140 °C, a temperature where either pure PSSA or Nafion are soft, as shown by dynamic mechanical analysis. The large concentration of sulfonic acid groups in PSSA is responsible for the high ionic exchange capacity of the composite membranes, reaching 2.25 mmol g(-1) for a composite with 83 wt % PSSA/PEGDA. The through-plane protonic conductivity of the best membrane is in excess of 0.1 S cm(-1) at 94 °C and 98% relative humidity (RH), decreasing to 0.042 S cm(-1) at 60% RH. These values are comparable or even higher than those of ionomers such as Nafion or polyelectrolytes such as PSSA. This combination of electric and viscoelastic properties with low cost underlines the potential of these nanocomposites as a bio-based alternative to other polymer membranes for application in fuel cells, redox flow batteries, or other devices requiring functional proton conducting elements, such as sensors and actuators.

  11. The aluminium content of infant formulas remains too high.

    Science.gov (United States)

    Chuchu, Nancy; Patel, Bhavini; Sebastian, Blaise; Exley, Christopher

    2013-10-08

    Recent research published in this journal highlighted the issue of the high content of aluminium in infant formulas. The expectation was that the findings would serve as a catalyst for manufacturers to address a significant problem of these, often necessary, components of infant nutrition. It is critically important that parents and other users have confidence in the safety of infant formulas and that they have reliable information to use in choosing a product with a lower content of aluminium. Herein, we have significantly extended the scope of the previous research and the aluminium content of 30 of the most widely available and often used infant formulas has been measured. Both ready-to-drink milks and milk powders were subjected to microwave digestion in the presence of 15.8 M HNO3 and 30% w/v H2O2 and the aluminium content of the digests was measured by TH GFAAS. Both ready-to-drink milks and milk powders were contaminated with aluminium. The concentration of aluminium across all milk products ranged from ca 100 to 430 μg/L. The concentration of aluminium in two soya-based milk products was 656 and 756 μg/L. The intake of aluminium from non-soya-based infant formulas varied from ca 100 to 300 μg per day. For soya-based milks it could be as high as 700 μg per day. All 30 infant formulas were contaminated with aluminium. There was no clear evidence that subsequent to the problem of aluminium being highlighted in a previous publication in this journal that contamination had been addressed and reduced. It is the opinion of the authors that regulatory and other non-voluntary methods are now required to reduce the aluminium content of infant formulas and thereby protect infants from chronic exposure to dietary aluminium.

  12. Engineering properties for high kitchen waste content municipal solid waste

    Institute of Scientific and Technical Information of China (English)

    Wu Gao; Yunmin Chen; Liangtong Zhan; Xuecheng Bian

    2015-01-01

    Engineering properties of municipal solid waste (MSW) depend largely on the waste’s initial composition and degree of degradation. MSWs in developing countries usually have a high kitchen waste content (called HKWC MSW). After comparing and analyzing the laboratory and field test results of physical composition, hydraulic properties, gas generation and gas permeability, and mechanical properties for HKWC MSW and low kitchen waste content MSW (called LKWC MSW), the following findings were obtained: (1) HKWC MSW has a higher initial water content (IWC) than LKWC MSW, but the field ca-pacities of decomposed HKWC and LKWC MSWs are similar; (2) the hydraulic conductivity and gas permeability for HKWC MSW are both an order of magnitude smaller than those for LKWC MSW; (3) compared with LKWC MSW, HKWC MSW has a higher landfill gas (LFG) generation rate but a shorter duration and a lower potential capacity; (4) the primary compression feature for decomposed HKWC MSW is similar to that of decomposed LKWC MSW, but the compression induced by degradation of HKWC MSW is greater than that of LKWC MSW; and (5) the shear strength of HKWC MSW changes significantly with time and strain. Based on the differences of engineering properties between these two kinds of MSWs, the geo-environmental issues in HKWC MSW landfills were analyzed, including high leachate production, high leachate mounds, low LFG collection efficiency, large settlement and slope stability problem, and corresponding advice for the management and design of HKWC MSW landfills was recommended.

  13. Liquid alternative diesel fuels with high hydrogen content

    Energy Technology Data Exchange (ETDEWEB)

    Hancsok, Jenoe; Varga, Zoltan; Eller, Zoltan; Poelczmann, Gyoergy [Pannonia Univ., Veszprem (Hungary). MOL Dept. of Hydrocarbon Processing; Kasza, Tamas [MOL Hungarian Oil and Gas Plc., Szazhalombatta (Hungary)

    2013-06-01

    Mobility is a keystone of the sustainable development. In the operation of the vehicles as the tools of mobility internal combustion engines, so thus Diesel engines will play a remarkable role in the next decades. Beside fossil fuels - used for power these engines - liquid alternative fuels have higher and higher importance, because of their known advantages. During the presentation the categorization possibilities based on the chronology of their development and application will be presented. The importance of fuels with high hydrogen content will be reviewed. Research and development activity in the field of such kind of fuels will be presented. During this developed catalytic systems and main performance properties of the product will be presented which were obtained in case of biogasoils produced by special hydrocracking of natural triglycerides and in case of necessity followed by isomerization; furthermore in case of synthetic biogasoils obtained by the isomerization hydrocracking of Fischer-Tropsch paraffins produced from biomass based synthesis gas. Excellent combustion properties (cetane number > 65-75), good cold flow properties and reduced harmful material emission due to the high hydrogen content (C{sub n}H{sub 2n+2}) are highlighted. Finally production possibilities of linear and branched paraffins based on lignocelluloses are briefly reviewed. Summarizing it was concluded that liquid hydrocarbons with high isoparaffin content are the most suitable fuels regarding availability, economical and environmental aspects, namely the sustainable development. (orig.)

  14. Engineering properties for high kitchen waste content municipal solid waste

    Directory of Open Access Journals (Sweden)

    Wu Gao

    2015-12-01

    Full Text Available Engineering properties of municipal solid waste (MSW depend largely on the waste's initial composition and degree of degradation. MSWs in developing countries usually have a high kitchen waste content (called HKWC MSW. After comparing and analyzing the laboratory and field test results of physical composition, hydraulic properties, gas generation and gas permeability, and mechanical properties for HKWC MSW and low kitchen waste content MSW (called LKWC MSW, the following findings were obtained: (1 HKWC MSW has a higher initial water content (IWC than LKWC MSW, but the field capacities of decomposed HKWC and LKWC MSWs are similar; (2 the hydraulic conductivity and gas permeability for HKWC MSW are both an order of magnitude smaller than those for LKWC MSW; (3 compared with LKWC MSW, HKWC MSW has a higher landfill gas (LFG generation rate but a shorter duration and a lower potential capacity; (4 the primary compression feature for decomposed HKWC MSW is similar to that of decomposed LKWC MSW, but the compression induced by degradation of HKWC MSW is greater than that of LKWC MSW; and (5 the shear strength of HKWC MSW changes significantly with time and strain. Based on the differences of engineering properties between these two kinds of MSWs, the geo-environmental issues in HKWC MSW landfills were analyzed, including high leachate production, high leachate mounds, low LFG collection efficiency, large settlement and slope stability problem, and corresponding advice for the management and design of HKWC MSW landfills was recommended.

  15. Dynamic-mechanical and thermomechanical properties of cellulose nanofiber/polyester resin composites.

    Science.gov (United States)

    Lavoratti, Alessandra; Scienza, Lisete Cristine; Zattera, Ademir José

    2016-01-20

    Composites of unsaturated polyester resin (UPR) and cellulose nanofibers (CNFs) obtained from dry cellulose waste of softwood (Pinus sp.) and hardwood (Eucalyptus sp.) were developed. The fiber properties and the influence of the CNFs in the dynamic-mechanical and thermomechanical properties of the composites were evaluated. CNFs with a diameter of 70-90 nm were obtained. Eucalyptus sp. has higher α-cellulose content than Pinus sp. fibers. The crystallinity of the cellulose pulps decreased after grinding. However, high values were still obtained. The chemical composition of the fibers was not significantly altered by the grinding process. Eucalyptus sp. CNF composites had water absorption close to the neat resin at 1 wt% filler. The dynamic-mechanical properties of Eucalyptus sp. CNFs were slightly increased and the thermal stability was improved.

  16. Cellulose extraction from Zoysia japonica pretreated by alumina-doped MgO in AMIMCl.

    Science.gov (United States)

    Liu, Le; Ju, Meiting; Li, Weizun; Jiang, Yang

    2014-11-26

    In this study, alumina-doped MgO was produced as a solid alkali for lignocellulose pretreatment. Pretreatment with alumina-doped MgO disrupted the lignocellulose structure and significantly reduced the lignin content of the Z. japonica. After pretreatment, Z. japonica showed significant solubility in 1-allyl-3-methylimidazolium chloride (AMIMCl). The similar high solubility of pretreated Z. japonica samples by original alumina-doped MgO and used alumina-doped MgO also proved that alumina-doped MgO had strong stability, which can be recycled and used repeatedly. The regenerated cellulose was similar to microcrystalline cellulose according to FTIR and NMR analyses. Compared to microcrystalline cellulose, only the crystallinity of the regenerated cellulose decreased.

  17. Contents

    Directory of Open Access Journals (Sweden)

    Editor IJRED

    2012-11-01

    Full Text Available International Journal of Renewable Energy Development www.ijred.com Volume 1             Number 3            October 2012                ISSN 2252- 4940   CONTENTS OF ARTICLES page Design and Economic Analysis of a Photovoltaic System: A Case Study 65-73 C.O.C. Oko , E.O. Diemuodeke, N.F. Omunakwe, and E. Nnamdi     Development of Formaldehyde Adsorption using Modified Activated Carbon – A Review 75-80 W.D.P Rengga , M. Sudibandriyo and M. Nasikin     Process Optimization for Ethyl Ester Production in Fixed Bed Reactor Using Calcium Oxide Impregnated Palm Shell Activated Carbon (CaO/PSAC 81-86 A. Buasri , B. Ksapabutr, M. Panapoy and N. Chaiyut     Wind Resource Assessment in Abadan Airport in Iran 87-97 Mojtaba Nedaei       The Energy Processing by Power Electronics and its Impact on Power Quality 99-105 J. E. Rocha and B. W. D. C. Sanchez       First Aspect of Conventional Power System Assessment for High Wind Power Plants Penetration 107-113 A. Merzic , M. Music, and M. Rascic   Experimental Study on the Production of Karanja Oil Methyl Ester and Its Effect on Diesel Engine 115-122 N. Shrivastava,  , S.N. Varma and M. Pandey  

  18. Investigation of mass transport properties of microfibrillated cellulose (MFC) films

    DEFF Research Database (Denmark)

    Minelli, Matteo; Baschetti, Marco Giacinti; Doghieri, Ferruccio

    2010-01-01

    sorption experiments confirmed the hydrophilic character of these cellulosic materials and showed a dual effect of glycerol which reduced the water uptake at low water activity while enhancing it at high relative humidity. The water diffusion in dry samples was remarkably slow for a porous material...... was observed in permeation experiments. Dry MFC films showed excellent oxygen barrier properties; however, a dramatic decrease in these properties was observed when the water content in the samples was increased....

  19. Cellulose nanomaterials review: structure, properties and nanocomposites

    OpenAIRE

    Moon, Robert J.; Martini, Ashlie; Nairn, John; Simonsen, John; Youngblood, Jeffrey

    2011-01-01

    This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them. It summarizes cellulose nanoparticles in terms of particle morphology, crystal structure, and properties. Also described are the self-assembly and rheological properties of cellulose nanoparticle suspensions. The methodology of composite processing and resulting properties are fully covered, with an emphasis on neat and high fraction...

  20. Chemically Crushed Wood Cellulose Fiber towards High-Performance Sodium-Ion Batteries.

    Science.gov (United States)

    Shen, Fei; Zhu, Hongli; Luo, Wei; Wan, Jiayu; Zhou, Lihui; Dai, Jiaqi; Zhao, Bin; Han, Xiaogang; Fu, Kun; Hu, Liangbing

    2015-10-21

    Carbon materials have attracted great interest as an anode for sodium-ion batteries (SIBs) due to their high performance and low cost. Here, we studied natural wood fiber derived hard carbon anodes for SIBs considering the abundance and low cost of wood. We discovered that a thermal carbonization of wood fiber led to a porous carbon with a high specific surface area of 586 m(2) g(-1), while a pretreatment with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) could effectively decrease it to 126 m(2) g(-1). When evaluating them as anodes for SIBs, we observed that the low surface area carbon resulted in a high initial Coulombic efficiency of 72% compared to 25% of the high surface area carbon. More importantly, the low surface area carbon exhibits an excellent cycling stability that a desodiation capacity of 196 mAh g(-1) can be delivered over 200 cycles at a current density of 100 mA g(-1), indicating a promising anode for low-cost SIBs.

  1. Synthesis of high intensity green emitting (Ba,Sr)SiO4:Eu2+ phosphors through cellulose assisted liquid phase precursor process

    Science.gov (United States)

    Humayoun, Usama Bin; Song, Young-Hyun; Lee, MinJi; Masato, Kakihana; Abe, Hiroshi; Toda, Kenji; Sato, Yasushi; Masaki, Takaki; Yoon, Dae-Ho

    2016-01-01

    Green emitting phosphor (Ba1-x,Sr1-x)SiO4:2xEu2+, x = 0.03, 0.05, 0.1, and 0.15 were synthesized through a Liquid Phase Precursor Process (LPP). Liquid phase precursor method is reported to result in phosphors with markedly increased emission intensities compared to other synthesis methods. Here microcrystalline cellulose (MCC) and hydroxypropyl cellulose (HPC) templates were studied to achieve high efficiency green phosphors. The phase formation was investigated by XRD analysis which showed the conformation of the Ba2SiO4 (JCPDS card number 761631) phase. The obtained samples exhibited broad excitation spectra with maximum at 430 nm and a green emission centered around 520 nm. An optimized dopant concentration was selected and the effect of two different types of cellulose, i.e. MCC and HPC templates on the emission properties was considered. It was found that the samples synthesized using HPC and fired at 1050 °C under a reducing atmosphere, showed a high intensity of almost 2 times that of the MCC sample. Further experiments were conducted by varying viscosity, particle weight, and molecular weight of the HPC template. It was found that the green emission from the (Ba,Sr)SiO4:Eu2+ increased with the increase in viscosity and molecular weight of the template.

  2. Efficient utilization of hemicellulose and cellulose in alkali liquor-pretreated corncob for bioethanol production at high solid loading by Spathaspora passalidarum U1-58.

    Science.gov (United States)

    Yu, Hai; Guo, Jian; Chen, Yefu; Fu, Gengxin; Li, Baozhong; Guo, Xuewu; Xiao, Dongguang

    2017-02-11

    The bioethanol fermentation of pretreated corncob was investigated using Spathaspora passalidarum U1-58, which simultaneously utilizes glucose and xylose for high-efficiency ethanol production. Two approaches, namely, separate hydrolysis and co-fermentation (SHCF) and simultaneous saccharification and co-fermentation (SSCF), were optimized to test the ethanol fermentation potential of U1-58. The highest ethanol titer of 42.46g/L and yield of 72.12% were acquired in SHCF, whereas 53.24g/L ethanol and yield of 75.35% were obtained in SSCF at solid-to-liquid ratio of 1:5 (w/v). Approximately 86.20% of cellulose and 82.99% of hemicellulose were consumed in SSCF after 96h, and at least 10.49g/L ethanol was produced from hemicellulose, which corresponded to 37.59% of the theoretical yield. Compared with the published cellulosic ethanol fermentation cases, the present work presented high ethanol titer and yield, and cellulose and hemicellulose could be efficiently utilized for ethanol production.

  3. Bacillus sp. strain P38: an efficient producer of L-lactate from cellulosic hydrolysate, with high tolerance for 2-furfural.

    Science.gov (United States)

    Peng, Lili; Wang, Limin; Che, Chengchuan; Yang, Ge; Yu, Bo; Ma, Yanhe

    2013-12-01

    In this study, efficient polymer-grade L-lactic acid production was achieved with the strain Bacillus sp. P38 by using cellulosic hydrolysate as the sole carbon source. In fed-batch fermentation, 180 g L(-1)L-lactic acid was obtained with a volumetric productivity of 2.4 g L(-1)h(-1) and a yield of 0.96 g g(-1) total reducing sugars. No D-isomer of lactic acid was detected in the broth. Strain P38 tolerated up to 10 g L(-1) 2-furfural, and lactate production was sharply inhibited only when the 2-furfural concentration was higher than 6 g L(-1). Moreover, strain P38 also tolerated high concentrations (>6 g L(-1)) of other fermentation inhibitors in cellulosic hydrolysate, such as vanillin and acetic acid, although it was slightly sensitive to formic acid. The efficient L-lactic acid production, combined with high inhibitor tolerance and efficient pentose utilization, indicate that Bacillus sp. P38 is a promising producer of polymer-grade L-lactic acid from cellulosic biomass.

  4. Content

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    Aim, content and methods are fundamental categories of both theoretical and practical general didactics. A quick glance in recent pedagogical literature on higher education, however, reveals a strong preoccupation with methods, i.e. how teaching should be organized socially (Biggs & Tang, 2007......; Race, 2001; Ramsden, 2003). This trend appears closely related to the ‘from-teaching-to-learning’ movement, which has had a strong influence on pedagogy since the early nineties (Keiding, 2007; Terhart, 2003). Another interpretation of the current interest in methodology can be derived from...... for selection of content (Klafki, 1985, 2000; Myhre, 1961; Nielsen, 2006). These attempts all share one feature, which is that criteria for selection of content appear very general and often, more or less explicitly, deal with teaching at the first Bologna-cycle; i.e. schooling at the primary and lower...

  5. Mechanical characterization of cellulose single nanofiber by atomic force microscopy

    Science.gov (United States)

    Zhai, Lindong; Kim, Jeong Woong; Lee, Jiyun; Kim, Jaehwan

    2017-04-01

    Cellulose fibers are strong natural fibers and they are renewable, biodegradable and the most abundant biopolymer in the world. So to develop new cellulose fibers based products, the mechanical properties of cellulose nanofibers would be a key. The atomic microscope is used to measure the mechanical properties of cellulose nanofibers based on 3-points bending of cellulose nanofiber. The cellulose nanofibers were generated for an aqueous counter collision system. The cellulose microfibers were nanosized under 200 MPa high pressure. The cellulose nanofiber suspension was diluted with DI water and sprayed on the silicon groove substrate. By performing a nanoscale 3-points bending test using the atomic force microscopy, a known force was applied on the center of the fiber. The elastic modulus of the single nanofiber is obtained by calculating the fiber deflection and several parameters. The elastic modulus values were obtained from different resources of cellulose such as hardwood, softwood and cotton.

  6. Fruit characterization of high oil content avocado varieties

    Directory of Open Access Journals (Sweden)

    Gómez-López Vicente Manuel

    2002-01-01

    Full Text Available To expand the data bank on avocado (Persea americana Mill. varieties all over the world, and to select good varieties for commercial or improving purposes, a partial fruit characterization of 13 high oil content (11.23-18.80% was performed. The chosen varieties are growing in a Venezuelan germplasm bank: Fuerte, Peruano, Lula, Ortega, Red Collinson, Alcemio, Araira 1, Pope, Ettinger, Gripiña 5, Barker, Duke, and Ryan. They were characterized for pulp oil and moisture; weight (whole fruit, seed, pulp and peel; length, width and fruit shape; peel characteristics (roughness, color and hand peeling; and ripeness time. The variety Ryan showed the highest oil content (18.80% and calorific value (191 Kcal/100 g wet flesh. Avocado varieties grown in Venezuela have generally less oil content and are generally lighter than those from other countries. Most of the varieties had low pulp proportion, and were pyriform, with rough green peel and difficult to hand peel. Red Collinson had an uncommon reddish peel. The ripening time was between 4 and 10 days after harvest.

  7. Production and effect of aldonic acids during enzymatic hydrolysis of lignocellulose at high dry matter content

    Directory of Open Access Journals (Sweden)

    Cannella David

    2012-04-01

    Full Text Available Abstract Background The recent discovery of accessory proteins that boost cellulose hydrolysis has increased the economical and technical efficiency of processing cellulose to bioethanol. Oxidative enzymes (e.g. GH61 present in new commercial enzyme preparations have shown to increase cellulose conversion yields. When using pure cellulose substrates it has been determined that both oxidized and unoxidized cellodextrin products are formed. We report the effect of oxidative activity in a commercial enzyme mix (Cellic CTec2 upon overall hydrolysis, formation of oxidized products and impact on β-glucosidase activity. The experiments were done at high solids loadings using a lignocellulosic substrate simulating commercially relevant conditions. Results The Cellic CTec2 contained oxidative enzymes which produce gluconic acid from lignocellulose. Both gluconic and cellobionic acid were produced during hydrolysis of pretreated wheat straw at 30% WIS. Up to 4% of released glucose was oxidized into gluconic acid using Cellic CTec2, whereas no oxidized products were detected when using an earlier cellulase preparation Celluclast/Novozym188. However, the cellulose conversion yield was 25% lower using Celluclast/Novozym188 compared to Cellic CTec2. Despite the advantage of the oxidative enzymes, it was shown that aldonic acids could be problematic to the hydrolytic enzymes. Hydrolysis experiments revealed that cellobionic acid was hydrolyzed by β-glucosidase at a rate almost 10-fold lower than for cellobiose, and the formed gluconic acid was an inhibitor of the β-glucosidase. Interestingly, the level of gluconic acid varied significantly with temperature. At 50°C (SHF conditions 35% less gluconic acid was produced compared to at 33°C (SSF conditions. We also found that in the presence of lignin, no reducing agent was needed for the function of the oxidative enzymes. Conclusions The presence of oxidative enzymes in Cellic CTec2 led to the formation of

  8. Production and effect of aldonic acids during enzymatic hydrolysis of lignocellulose at high dry matter content.

    Science.gov (United States)

    Cannella, David; Hsieh, Chia-Wen C; Felby, Claus; Jørgensen, Henning

    2012-04-30

    The recent discovery of accessory proteins that boost cellulose hydrolysis has increased the economical and technical efficiency of processing cellulose to bioethanol. Oxidative enzymes (e.g. GH61) present in new commercial enzyme preparations have shown to increase cellulose conversion yields. When using pure cellulose substrates it has been determined that both oxidized and unoxidized cellodextrin products are formed. We report the effect of oxidative activity in a commercial enzyme mix (Cellic CTec2) upon overall hydrolysis, formation of oxidized products and impact on β-glucosidase activity. The experiments were done at high solids loadings using a lignocellulosic substrate simulating commercially relevant conditions. The Cellic CTec2 contained oxidative enzymes which produce gluconic acid from lignocellulose. Both gluconic and cellobionic acid were produced during hydrolysis of pretreated wheat straw at 30% WIS. Up to 4% of released glucose was oxidized into gluconic acid using Cellic CTec2, whereas no oxidized products were detected when using an earlier cellulase preparation Celluclast/Novozym188. However, the cellulose conversion yield was 25% lower using Celluclast/Novozym188 compared to Cellic CTec2. Despite the advantage of the oxidative enzymes, it was shown that aldonic acids could be problematic to the hydrolytic enzymes. Hydrolysis experiments revealed that cellobionic acid was hydrolyzed by β-glucosidase at a rate almost 10-fold lower than for cellobiose, and the formed gluconic acid was an inhibitor of the β-glucosidase.Interestingly, the level of gluconic acid varied significantly with temperature. At 50°C (SHF conditions) 35% less gluconic acid was produced compared to at 33°C (SSF conditions). We also found that in the presence of lignin, no reducing agent was needed for the function of the oxidative enzymes. The presence of oxidative enzymes in Cellic CTec2 led to the formation of cellobionic and gluconic acid during hydrolysis of

  9. EFFECT OF CARBON CONTENT ON MICROSTRUCTURE AND PROPERTIES OF HIGH STRENGTH AND HIGH ELONGATION STEELS

    Institute of Scientific and Technical Information of China (English)

    Y. Chen; X. Chen; P.H. Li; S.K. Pu; Z.X. Yuan; B.F. Xu; D.X. Lou; A.M. Guo; S.B.Zhou

    2003-01-01

    The microstructure and mechanical properties of new kind of hot-rolled high strengthand high elongation steels with retained austenite were studied by discussing the in-fluence of different carbon content. The research results indicate that carbon contenthas a significant effect on retaining austenite and consequently resulting in high elon-gation. Besides, new findings about relationship between carbon content and retainedaustenite as well as properties were discussed in the paper.

  10. Cellulose Synthases and Synthesis in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Anne Endler; Staffan Persson

    2011-01-01

    Plant cell walls are complex structures composed of high-molecular-weight polysaccharides,proteins,and lignins. Among the wall polysaccharides,cellulose,a hydrogen-bonded β-1,4-linked glucan microfibril,is the main load-bearing wall component and a key precursor for industrial applications. Cellulose is synthesized by large multi-meric cellulose synthase (CesA) complexes,tracking along cortical microtubules at the plasma membrane. The only known components of these complexes are the cellulose synthase proteins. Recent studies have identified tentative interaction partners for the CesAs and shown that the migratory patterns of the CesA complexes depend on phosphorylation status. These advances may become good platforms for expanding our knowledge about cellulose synthesis in the near future. In addition,our current understanding of cellulose chain polymerization in the context of the CesA complex is discussed.

  11. Assessment of solvents for cellulose dissolution.

    Science.gov (United States)

    Ghasemi, Mohammad; Tsianou, Marina; Alexandridis, Paschalis

    2017-03-01

    A necessary step in the processing of biomass is the pretreatment and dissolution of cellulose. A good solvent for cellulose involves high diffusivity, aggressiveness in decrystallization, and capability of disassociating the cellulose chains. However, it is not clear which of these factors and under what conditions should be improved in order to obtain a more effective solvent. To this end, a newly-developed phenomenological model has been applied to assess the controlling mechanism of cellulose dissolution. Among the findings, the cellulose fibers remain crystalline almost to the end of the dissolution process for decrystallization-controlled kinetics. In such solvents, decreasing the fiber crystallinity, e.g., via pretreatment, would result in a considerable increase in the dissolution rate. Such insights improve the understanding of cellulose dissolution and facilitate the selection of more efficient solvents and processing conditions for biomass. Specific examples of solvents are provided where dissolution is limited due to decrystallization or disentanglement.

  12. Image analysis benchmarking methods for high-content screen design.

    Science.gov (United States)

    Fuller, C J; Straight, A F

    2010-05-01

    The recent development of complex chemical and small interfering RNA (siRNA) collections has enabled large-scale cell-based phenotypic screening. High-content and high-throughput imaging are widely used methods to record phenotypic data after chemical and small interfering RNA treatment, and numerous image processing and analysis methods have been used to quantify these phenotypes. Currently, there are no standardized methods for evaluating the effectiveness of new and existing image processing and analysis tools for an arbitrary screening problem. We generated a series of benchmarking images that represent commonly encountered variation in high-throughput screening data and used these image standards to evaluate the robustness of five different image analysis methods to changes in signal-to-noise ratio, focal plane, cell density and phenotype strength. The analysis methods that were most reliable, in the presence of experimental variation, required few cells to accurately distinguish phenotypic changes between control and experimental data sets. We conclude that by applying these simple benchmarking principles an a priori estimate of the image acquisition requirements for phenotypic analysis can be made before initiating an image-based screen. Application of this benchmarking methodology provides a mechanism to significantly reduce data acquisition and analysis burdens and to improve data quality and information content.

  13. Cellulose metabolism in plants.

    Science.gov (United States)

    Hayashi, Takahisa; Yoshida, Kouki; Park, Yong Woo; Konishi, Teruko; Baba, Kei'ichi

    2005-01-01

    Many bacterial genomes contain a cellulose synthase operon together with a cellulase gene, indicating that cellulase is required for cellulose biosynthesis. In higher plants, there is evidence that cell growth is enhanced by the overexpression of cellulase and prevented by its suppression. Cellulase overexpression could modify cell walls not only by trimming off the paracrystalline sites of cellulose microfibrils, but also by releasing xyloglucan tethers between the microfibrils. Mutants for membrane-anchored cellulase (Korrigan) also show a typical phenotype of prevention of cellulose biosynthesis in tissues. All plant cellulases belong to family 9, which endohydrolyzes cellulose, but are not strong enough to cause the bulk degradation of cellulose microfibrils in a plant body. It is hypothesized that cellulase participates primarily in repairing or arranging cellulose microfibrils during cellulose biosynthesis in plants. A scheme for the roles of plant cellulose and cellulases is proposed.

  14. Nitration of Wood Cellulose in HNO3/Organic Solvent Medium

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A steam explosion pretreatment at various severities was applied to pure wood cellulose; the influences of steam pretreatment on the morphological structure, the hydrophilic property and viscosity-average molecular weight of cellulose were evaluated. The nitration of steam-exploded cellulose was carried out in the nitrating agent medium (HNO3/organic solvent). The performance indexes of nitrocellulose, prepared from original and steam exploded samples, were determined by using the polarized optical microscope. The results show that after pretreatment the reactivity of the three hydroxyl groups in anhydroglucose unit of cellulose is improved, and the nitrogen content and the uniformity of NC from steam exploded cellulose observably increas.

  15. Chemo-catalytic valorization of cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Palkovits, R. [RWTH Aachen Univ. (Germany). Inst. fuer Technische und Makromolekulare Chemie

    2012-07-01

    Cellulose can be utilized as carbon source for the production of novel platform molecules as well as fuel motifs. Promising transformation strategies cover the hydrolytic hydrogenation or hydrogenolysis of cellulose to sugar alcohols, the hydrolysis of cellulose to glucose followed by dehydration to 5-hydroxymethylfurfural or levulinic acid and the further hydrogenation of levulinic acid to {gamma}-valerolactone. Main challenges result from the high degree of functionalization of cellulosic feedstocks. In line, processes are carried out in liquid phase utilizing rather polar solvents and aiming for a tailored defunctionalisation of these oxygen rich compounds. Consequently, such transformations require novel strategies concerning the development of suitable catalysts and appropriate process concepts. (orig.)

  16. Chemo-catalytic valorization of cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Palkovits, R. [RWTH Aachen Univ. (Germany). Inst. fuer Technische und Makromolekulare Chemie

    2012-07-01

    Cellulose can be utilized as carbon source for the production of novel platform molecules as well as fuel motifs. Promising transformation strategies cover the hydrolytic hydrogenation or hydrogenolysis of cellulose to sugar alcohols, the hydrolysis of cellulose to glucose followed by dehydration to 5-hydroxymethylfurfural or levulinic acid and the further hydrogenation of levulinic acid to {gamma}-valerolactone. Main challenges result from the high degree of functionalization of cellulosic feedstocks. In line, processes are carried out in liquid phase utilizing rather polar solvents and aiming for a tailored defunctionalisation of these oxygen rich compounds. Consequently, such transformations require novel strategies concerning the development of suitable catalysts and appropriate process concepts. (orig.)

  17. Effects of cellulose, xylan and lignin content on biomass pyrolysis characteristics and product distribution%纤维素木聚糖和木质素含量对生物质热解特性及产物的影响

    Institute of Scientific and Technical Information of China (English)

    李小华; 焦丽华; 樊永胜; 陈磊; 蔡忆昔

    2015-01-01

    calculated value, it could be concluded that cellulose pyrolysis was beneficial to the reduction of the solid residue while lignin pyrolysis products could promote the decomposing of sugars. Xylan had a negative effect on the cellulose pyrolysis and could benefit the low-temperature pyrolysis of lignin. The co-pyrolysis of xylan and lignin had little influence on the bio-oil composition. Therefore, biomass with high cellulose content could foster the bio-oil yield and a certain amount of lignin could promote the decomposing of cellulose. The results provide a theoretical basis for further improving the yield and quality of the bio-oil.

  18. High resolution DNA content measurements of mammalian sperm

    Energy Technology Data Exchange (ETDEWEB)

    Pinkel, D.; Lake, S.; Gledhill, B.L.; Van Dilla, M.A.; Stephenson, D.; Watchmaker, G.

    1982-01-01

    The high condensation and flat shape of the mammalian sperm nucleus present unique difficulties to flow cytometric measurement of DNA content. Chromatin compactness makes quantitative fluorescent staining for DNA difficult and causes a high index of refraction. The refractive index makes optical measurements sensitive to sperm head orientation. We demonstrate that the optical problems can be overcome using the commercial ICP22 epiillumination flow cytometer (Ortho Instruments, Westwood, MA) or a specially built cell orientating flow cytometer (OFCM). The design and operation of the OFCM are described. Measurements of the angular dependence of fluorescence from acriflavine stained rabbit sperm show that it is capable of orienting flat sperm with a tolerance of +-7/sup 0/. Differences in the angular dependence for the similarly shaped bull and rabbit sperm allow discrimination of these cells. We show that DNA staining with 4-6 diamidino-2-phenylindole (DAPI) or an ethidium bromide mithramycin combination allows resolution of the X and Y populations in mouse sperm. They have also been successful with sperm from the bull, ram, rabbit, and boar. Reliable results with human sperm are not obtained. The accuracy of the staining and measurement techniques are verified by the correct determination of the relative content of these two populations in sperm from normal mice and those with the Cattanach (7 to X) translocation. Among the potential uses of these techniques are measurement of DNA content errors induced in sperm due to mutagen exposure, and assessment of the fractions of X and Y sperm in semen that may have one population artifically enriched.

  19. The Gray Institute 'open' high-content, fluorescence lifetime microscopes.

    Science.gov (United States)

    Barber, P R; Tullis, I D C; Pierce, G P; Newman, R G; Prentice, J; Rowley, M I; Matthews, D R; Ameer-Beg, S M; Vojnovic, B

    2013-08-01

    We describe a microscopy design methodology and details of microscopes built to this 'open' design approach. These demonstrate the first implementation of time-domain fluorescence microscopy in a flexible automated platform with the ability to ease the transition of this and other advanced microscopy techniques from development to use in routine biology applications. This approach allows easy expansion and modification of the platform capabilities, as it moves away from the use of a commercial, monolithic, microscope body to small, commercial off-the-shelf and custom made modular components. Drawings and diagrams of our microscopes have been made available under an open license for noncommercial use at http://users.ox.ac.uk/~atdgroup. Several automated high-content fluorescence microscope implementations have been constructed with this design framework and optimized for specific applications with multiwell plates and tissue microarrays. In particular, three platforms incorporate time-domain FLIM via time-correlated single photon counting in an automated fashion. We also present data from experiments performed on these platforms highlighting their automated wide-field and laser scanning capabilities designed for high-content microscopy. Devices using these designs also form radiation-beam 'end-stations' at Oxford and Surrey Universities, showing the versatility and extendibility of this approach. © 2013 The Authors. Journal of Microscopy published by John Wiley & Sons Ltd on behalf of Royal Microscopical Society.

  20. High fat intake by ponies reduces both apparent digestibility of dietary cellulose and cellulose fermentation by faeces and isolated caecal and colonic contents

    NARCIS (Netherlands)

    Jansen, W.L.; Cone, J.W.; Geelen, S.N.J.; Sloet van Oldruitenborgh-Oosterbaan, M.M.; Gelder, van A.H.; Oude Elferink, S.J.W.H.; Beynen, A.C.

    2007-01-01

    Inclusion of extra fat in the diet of horses, at the expense of an iso-energetic amount of nonstructural carbohydrates, has been shown to decrease the apparent digestibility of the various dietary fiber fractions, but the mechanism was unknown. It was hypothesized that inclusion of extra fat in the

  1. Runaway electron dynamics in tokamak plasmas with high impurity content

    Science.gov (United States)

    Martín-Solís, J. R.; Loarte, A.; Lehnen, M.

    2015-09-01

    The dynamics of high energy runaway electrons is analyzed for plasmas with high impurity content. It is shown that modified collision terms are required in order to account for the collisions of the relativistic runaway electrons with partially stripped impurity ions, including the effect of the collisions with free and bound electrons, as well as the scattering by the full nuclear and the electron-shielded ion charge. The effect of the impurities on the avalanche runaway growth rate is discussed. The results are applied, for illustration, to the interpretation of the runaway electron behavior during disruptions, where large amounts of impurities are expected, particularly during disruption mitigation by massive gas injection. The consequences for the electron synchrotron radiation losses and the resulting runaway electron dynamics are also analyzed.

  2. High-content screening of functional genomic libraries.

    Science.gov (United States)

    Rines, Daniel R; Tu, Buu; Miraglia, Loren; Welch, Genevieve L; Zhang, Jia; Hull, Mitchell V; Orth, Anthony P; Chanda, Sumit K

    2006-01-01

    Recent advances in functional genomics have enabled genome-wide genetic studies in mammalian cells. These include the establishment of high-throughput transfection and viral propagation methodologies, the production of large-scale cDNA and siRNA libraries, and the development of sensitive assay detection processes and instrumentation. The latter has been significantly facilitated by the implementation of automated microscopy and quantitative image analysis, collectively referred to as high-content screening (HCS), toward cell-based functional genomics application. This technology can be applied to whole genome analysis of discrete molecular and phenotypic events at the level of individual cells and promises to significantly expand the scope of functional genomic analyses in mammalian cells. This chapter provides a comprehensive guide for curating and preparing function genomics libraries and performing HCS at the level of the genome.

  3. Mechanical characterization of cellulosic thecal plates in dinoflagellates by nanoindentation.

    Science.gov (United States)

    Lau, Ringo K L; Kwok, Alvin C M; Chan, W K; Zhang, T Y; Wong, Joseph T Y

    2007-02-01

    Dinoflagellates constitute an important group of microorganisms. Symbiotic dinoflagellates are responsible for the primary production of coral reef ecosystems and the phenomenon of their demise is known as "coral bleaching." Blooming of the planktonic dinoflagellates is the major cause of "red tides." Many dinoflagellates have prominent membrane-bound thecal plates at their cell cortices. These thecal plates have high cellulose content and are biologically fabricated into various shapes. However, the mechanical properties of theca have not previously been characterized; understanding these properties, including hardness and elastic modulus, will give insights into the ecological significance and biotechnological potential of bio-fabricated structures. A series of nanoindentation tests were performed on various locations of cellulosic thecal plates isolated from the dinoflagellates Alexandrium catenella and Lingulodinium polyedrum. Despite having transparent properties, thecal plates possess mechanical properties comparable to softwood cell walls, implicating their role as a protective cell covering. Consistent measurements were obtained when indentation was performed at various locations, which contrasts with the high variability of cellulose microfibers from plant sources. The present study demonstrated the novel properties of this potential new source of cellulose.

  4. Microfibrillated cellulose and new nanocomposite materials: a review

    DEFF Research Database (Denmark)

    Siró, Istvan; Plackett, David

    2010-01-01

    Due to their abundance, high strength and stiffness, low weight and biodegradability, nano-scale cellulose fiber materials (e.g., microfibrillated cellulose and bacterial cellulose) serve as promising candidates for bio-nanocomposite production. Such new high-value materials are the subject...... in order to address this hurdle. This review summarizes progress in nanocellulose preparation with a particular focus on microfibrillated cellulose and also discusses recent developments in bio-nanocomposite fabrication based on nanocellulose....

  5. Nanomechanics of cellulose crystals and cellulose-based polymer composites

    Science.gov (United States)

    Pakzad, Anahita

    Cellulose-polymer composites have potential applications in aerospace and transportation areas where lightweight materials with high mechanical properties are needed. In addition, these economical and biodegradable composites have been shown to be useful as polymer electrolytes, packaging structures, optoelectronic devices, and medical implants such as wound dressing and bone scaffolds. In spite of the above mentioned advantages and potential applications, due to the difficulties associated with synthesis and processing techniques, application of cellulose crystals (micro and nano sized) for preparation of new composite systems is limited. Cellulose is hydrophilic and polar as opposed to most of common thermoplastics, which are non-polar. This results in complications in addition of cellulose crystals to polymer matrices, and as a result in achieving sufficient dispersion levels, which directly affects the mechanical properties of the composites. As in other composite materials, the properties of cellulose-polymer composites depend on the volume fraction and the properties of individual phases (the reinforcement and the polymer matrix), the dispersion quality of the reinforcement through the matrix and the interaction between CNCs themselves and CNC and the matrix (interphase). In order to develop economical cellulose-polymer composites with superior qualities, the properties of individual cellulose crystals, as well as the effect of dispersion of reinforcements and the interphase on the properties of the final composites should be understood. In this research, the mechanical properties of CNC polymer composites were characterized at the macro and nano scales. A direct correlation was made between: - Dispersion quality and macro-mechanical properties - Nanomechanical properties at the surface and tensile properties - CNC diameter and interphase thickness. Lastly, individual CNCs from different sources were characterized and for the first time size-scale effect on

  6. Characterization of new natural cellulosic fiber from Cissus quadrangularis stem.

    Science.gov (United States)

    Indran, S; Raj, R Edwin

    2015-03-01

    Polymer composite has contributed tremendously for energy efficient technologies in automotive and aero industries. Environmental and health concerns related to the carcinogenic nature of artificial fiber in polymer composite needs a retrofit. Eco friendly natural cellulosic fiber extract from the stem of Cissus quadrangularis plant is extensively characterized to consider as a viable alternative for man-made hazardous fibers. Anatomical study, chemical analysis, physical analysis, FTIR, XRD, SEM analysis and thermo gravimetric analysis were done to establish the certainty of using them as reinforcement fiber. Its light weight and the presence of high cellulose content (82.73%) with very little wax (0.18%) provide high specific strength and good bonding properties in composite manufacturing. The flaky honeycomb outer surface revealed through electron microscopy contributes for high modulus in CQ stem fiber and thermo gravimetric analysis ensures thermal stability up to 270 °C, which is within the polymerization process temperature.

  7. The dust content of QSO hosts at high redshift

    CERN Document Server

    Calura, F; Vignali, C; Pozzi, F; Pipino, A; Matteucci, F

    2013-01-01

    Infrared observations of high-z quasar (QSO) hosts indicate the presence of large masses of dust in the early universe. When combined with other observables, such as neutral gas masses and star formation rates, the dust content of z~6 QSO hosts may help constraining their star formation history. We have collected a database of 58 sources from the literature discovered by various surveys and observed in the FIR. We have interpreted the available data by means of chemical evolution models for forming proto-spheroids, investigating the role of the major parameters regulating star formation and dust production. For a few systems, given the derived small dynamical masses, the observed dust content can be explained only assuming a top-heavy initial mass function, an enhanced star formation efficiency and an increased rate of dust accretion. However, the possibility that, for some systems, the dynamical mass has been underestimated cannot be excluded. If this were the case, the dust mass can be accounted for by stan...

  8. Isolation and characterization of two cellulose morphology mutants of Gluconacetobacter hansenii ATCC23769 producing cellulose with lower crystallinity.

    Directory of Open Access Journals (Sweden)

    Ying Deng

    Full Text Available Gluconacetobacter hansenii, a Gram-negative bacterium, produces and secrets highly crystalline cellulose into growth medium, and has long been used as a model system for studying cellulose synthesis in higher plants. Cellulose synthesis involves the formation of β-1,4 glucan chains via the polymerization of glucose units by a multi-enzyme cellulose synthase complex (CSC. These glucan chains assemble into ordered structures including crystalline microfibrils. AcsA is the catalytic subunit of the cellulose synthase enzymes in the CSC, and AcsC is required for the secretion of cellulose. However, little is known about other proteins required for the assembly of crystalline cellulose. To address this question, we visually examined cellulose pellicles formed in growth media of 763 individual colonies of G. hansenii generated via Tn5 transposon insertion mutagenesis, and identified 85 that produced cellulose with altered morphologies. X-ray diffraction analysis of these 85 mutants identified two that produced cellulose with significantly lower crystallinity than wild type. The gene disrupted in one of these two mutants encoded a lysine decarboxylase and that in the other encoded an alanine racemase. Solid-state NMR analysis revealed that cellulose produced by these two mutants contained increased amounts of non-crystalline cellulose and monosaccharides associated with non-cellulosic polysaccharides as compared to the wild type. Monosaccharide analysis detected higher percentages of galactose and mannose in cellulose produced by both mutants. Field emission scanning electron microscopy showed that cellulose produced by the mutants was unevenly distributed, with some regions appearing to contain deposition of non-cellulosic polysaccharides; however, the width of the ribbon was comparable to that of normal cellulose. As both lysine decarboxylase and alanine racemase are required for the integrity of peptidoglycan, we propose a model for the role of

  9. Nucleic acids encoding a cellulose binding domain

    Energy Technology Data Exchange (ETDEWEB)

    Shoseyov, Oded (Karmey Yosef, IL); Shpiegl, Itai (Rehovot, IL); Goldstein, Marc A. (Davis, CA); Doi, Roy H. (Davis, CA)

    1996-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  10. Semisolid Slurry Preparation of Die Steel with High Chromium Content

    Institute of Scientific and Technical Information of China (English)

    MAO Wei-min; ZHAO Ai-min; ZHANG Li-juan; ZHONG Xue-you

    2004-01-01

    The semisolid slurry preparation of die steels Cr12 and Cr12MoV with high chromium content was studied. The results show that the semisolid slurry of both steels with solid of 40 %-60 % can be made by electromagnetic stirring method and is easy to be discharged from the bottom little hole of the stirring chamber. The sizes of the spherical primary austenite in the slurry of die steels Cr12 and Cr12MoV are 50-100 μm and 80-150 μm, respectively. The homogeneous temperature field and solute field for both steel melts are obtained. The strong temperature fluctuation in the melt with many fine primary austenite grains occurs and the remelting of the secondary arm roots at the same time is accelerated because of the electromagnetic stirring. These are the most important reasons for deposition of spherical primary austenite grains.

  11. High-Content Screening for Quantitative Cell Biology.

    Science.gov (United States)

    Mattiazzi Usaj, Mojca; Styles, Erin B; Verster, Adrian J; Friesen, Helena; Boone, Charles; Andrews, Brenda J

    2016-08-01

    High-content screening (HCS), which combines automated fluorescence microscopy with quantitative image analysis, allows the acquisition of unbiased multiparametric data at the single cell level. This approach has been used to address diverse biological questions and identify a plethora of quantitative phenotypes of varying complexity in numerous different model systems. Here, we describe some recent applications of HCS, ranging from the identification of genes required for specific biological processes to the characterization of genetic interactions. We review the steps involved in the design of useful biological assays and automated image analysis, and describe major challenges associated with each. Additionally, we highlight emerging technologies and future challenges, and discuss how the field of HCS might be enhanced in the future.

  12. Preparation of Garlic Powder with High Allicin Content

    Institute of Scientific and Technical Information of China (English)

    LI Yu; XU Shi-ying

    2007-01-01

    Garlic powder with high allicin content was prepared using microwave-vacuum and vacuum drying as well as microencapsulation to protect alliinase activity throughout the stomach and improve the ratio of alliin transforming into allicin. The results showed that the optimal drying condition was 376.1 W for 3 min, 282.1 W for 3 min, 188 W for 9 min, and 94 W for 3 min. The thiosulfinates retention after drying was 90.2%. Following drying, the garlic powder was microencapsulated by modified fluidized bed technique. Scanning electron microscope revealed good integrity and core materials that were embedded in the microcapsules. Studies on the release kinetics of microencapsulated garlic granulates in vitro using simulated intestinal fluid indicated that release of garlic powder could be controlled in the intestine by passing stomach conditions.

  13. Automation in high-content flow cytometry screening.

    Science.gov (United States)

    Naumann, U; Wand, M P

    2009-09-01

    High-content flow cytometric screening (FC-HCS) is a 21st Century technology that combines robotic fluid handling, flow cytometric instrumentation, and bioinformatics software, so that relatively large numbers of flow cytometric samples can be processed and analysed in a short period of time. We revisit a recent application of FC-HCS to the problem of cellular signature definition for acute graft-versus-host-disease. Our focus is on automation of the data processing steps using recent advances in statistical methodology. We demonstrate that effective results, on par with those obtained via manual processing, can be achieved using our automatic techniques. Such automation of FC-HCS has the potential to drastically improve diagnosis and biomarker identification.

  14. High-content analysis for drug delivery and nanoparticle applications.

    Science.gov (United States)

    Brayden, David J; Cryan, Sally-Ann; Dawson, Kenneth A; O'Brien, Peter J; Simpson, Jeremy C

    2015-08-01

    High-content analysis (HCA) provides quantitative multiparametric cellular fluorescence data. From its origins in discovery toxicology, it is now addressing fundamental questions in drug delivery. Nanoparticles (NPs), polymers, and intestinal permeation enhancers are being harnessed in drug delivery systems to modulate plasma membrane properties and the intracellular environment. Identifying comparative mechanistic cytotoxicity on sublethal events is crucial to expedite the development of such systems. NP uptake and intracellular routing pathways are also being dissected using chemical and genetic perturbations, with the potential to assess the intracellular fate of targeted and untargeted particles in vitro. As we discuss here, HCA is set to make a major impact in preclinical delivery research by elucidating the intracellular pathways of NPs and the in vitro mechanistic-based toxicology of formulation constituents.

  15. Rheology and thermal degradation of isocyanate-functionalized methyl cellulose-based oleogels.

    Science.gov (United States)

    Gallego, R; Arteaga, J F; Valencia, C; Franco, J M

    2013-10-15

    The -NCO-functionalization of methyl cellulose with HMDI and its application to chemically gel the castor oil is explored in this work by analyzing the influence of functionalization degree on the rheological and thermogravimetric behavior of resulting chemical oleogels. With this aim, different methyl cellulose chemical modifications were achieved by limiting the proportion of HMDI and, subsequently, oleogels were obtained by dispersing these polymers in castor oil and promoting the reaction between those biopolymers and the hydroxyl groups located in the ricinoleic fatty acid chain. -NCO-functionalized methyl cellulose-based oleogels were characterized from themogravimetric and rheological points of view. Suitable thermal resistance and rheological characteristics were found in order to propose these oleogels as promising bio-based alternatives to traditional lubricating greases based on non-renewable resources. In general, -NCO-functionalized methyl cellulose thermally decomposed in three main steps whereas resulting oleogels thermal decomposition takes place in one main single stage which comprises the thermal degradation of both the polymer and the castor oil. Temperature range for thermal degradation is broadened when using highly -NCO-functionalized methyl cellulose. A cross-linked viscoelastic gel was obtained with methyl cellulose functionalized in a relatively low degree (around 6% -NCO molar content). The rheological properties of highly functionalized methyl cellulose-based oleogels evolve during several months of aging, but mainly during the first week, due to the progress of the reaction between -NCO functional groups and castor oil -OH groups. SAOS functions analyzed and oleogel relative elasticity increase with the functionalization degree. Oleogel linear viscoelastic response is also extremely dependent on NCO-functionalized methyl cellulose concentration.

  16. Using satellite vegetation and compound topographic indices to map highly erodible cropland buffers for cellulosic biofuel crop developments in eastern Nebraska, USA

    Science.gov (United States)

    Gu, Yingxin; Wylie, Bruce K.

    2015-01-01

    Cultivating annual row crops in high topographic relief waterway buffers has negative environmental effects and can be environmentally unsustainable. Growing perennial grasses such as switchgrass (Panicum virgatum L.) for biomass (e.g., cellulosic biofuel feedstocks) instead of annual row crops in these high relief waterway buffers can improve local environmental conditions (e.g., reduce soil erosion and improve water quality through lower use of fertilizers and pesticides) and ecosystem services (e.g., minimize drought and flood impacts on production; improve wildlife habitat, plant vigor, and nitrogen retention due to post-senescence harvest for cellulosic biofuels; and serve as carbon sinks). The main objectives of this study are to: (1) identify cropland areas with high topographic relief (high runoff potentials) and high switchgrass productivity potential in eastern Nebraska that may be suitable for growing switchgrass, and (2) estimate the total switchgrass production gain from the potential biofuel areas. Results indicate that about 140,000 hectares of waterway buffers in eastern Nebraska are suitable for switchgrass development and the total annual estimated switchgrass biomass production for these suitable areas is approximately 1.2 million metric tons. The resulting map delineates high topographic relief croplands and provides useful information to land managers and biofuel plant investors to make optimal land use decisions regarding biofuel crop development and ecosystem service optimization in eastern Nebraska.

  17. Oxy-combustion of high water content fuels

    Science.gov (United States)

    Yi, Fei

    As the issues of global warming and the energy crisis arouse extensive concern, more and more research is focused on maximizing energy efficiency and capturing CO2 in power generation. To achieve this, in this research, we propose an unconventional concept of combustion - direct combustion of high water content fuels. Due to the high water content in the fuels, they may not burn under air-fired conditions. Therefore, oxy-combustion is applied. Three applications of this concept in power generation are proposed - direct steam generation for the turbine cycle, staged oxy-combustion with zero flue gas recycle, and oxy-combustion in a low speed diesel-type engine. The proposed processes could provide alternative approaches to directly utilize fuels which intrinsically have high water content. A large amount of energy to remove the water, when the fuels are utilized in a conventional approach, is saved. The properties and difficulty in dewatering high water content fuels (e.g. bioethanol, microalgae and fine coal) are summarized. These fuels include both renewable and fossil fuels. In addition, the technique can also allow for low-cost carbon capture due to oxy-combustion. When renewable fuel is utilized, the whole process can be carbon negative. To validate and evaluate this concept, the research focused on the investigation of the flame stability and characteristics for high water content fuels. My study has demonstrated the feasibility of burning fuels that have been heavily diluted with water in a swirl-stabilized burner. Ethanol and 1-propanol were first tested as the fuels and the flame stability maps were obtained. Flame stability, as characterized by the blow-off limit -- the lowest O2 concentration when a flame could exist under a given oxidizer flow rate, was determined as a function of total oxidizer flow rate, fuel concentration and nozzle type. Furthermore, both the gas temperature contour and the overall ethanol concentration in the droplets along the

  18. A high performance Trichoderma reesei strain that reveals the importance of xylanase III in cellulosic biomass conversion.

    Science.gov (United States)

    Nakazawa, Hikaru; Kawai, Tetsushi; Ida, Noriko; Shida, Yosuke; Shioya, Kouki; Kobayashi, Yoshinori; Okada, Hirofumi; Tani, Shuji; Sumitani, Jun-ichi; Kawaguchi, Takashi; Morikawa, Yasushi; Ogasawara, Wataru

    2016-01-01

    The ability of the Trichoderma reesei X3AB1strain enzyme preparations to convert cellulosic biomass into fermentable sugars is enhanced by the replacement of xyn3 by Aspergillus aculeatus β-glucosidase 1 gene (aabg1), as shown in our previous study. However, subsequent experiments using T. reesei extracts supplemented with the glycoside hydrolase (GH) family 10 xylanase III (XYN III) and GH Family 11 XYN II showed increased conversion of alkaline treated cellulosic biomass, which is rich in xylan, underscoring the importance of XYN III. To attain optimal saccharifying potential in T. reesei, we constructed two new strains, C1AB1 and E1AB1, in which aabg1 was expressed heterologously by means of the cbh1 or egl1 promoters, respectively, so that the endogenous XYN III synthesis remained intact. Due to the presence of wild-type xyn3 in T. reesei E1AB1, enzymes prepared from this strain were 20-30% more effective in the saccharification of alkaline-pretreated rice straw than enzyme extracts from X3AB1, and also outperformed recent commercial cellulase preparations. Our results demonstrate the importance of XYN III in the conversion of alkaline-pretreated cellulosic biomass by T. reesei.

  19. Expression of a mutant form of cellulose synthase AtCesA7 causes dominant negative effect on cellulose biosynthesis.

    Science.gov (United States)

    Zhong, Ruiqin; Morrison, W Herbert; Freshour, Glenn D; Hahn, Michael G; Ye, Zheng-Hua

    2003-06-01

    Cellulose synthase catalytic subunits (CesAs) have been implicated in catalyzing the biosynthesis of cellulose, the major component of plant cell walls. Interactions between CesA subunits are thought to be required for normal cellulose synthesis, which suggests that incorporation of defective CesA subunits into cellulose synthase complex could potentially cause a dominant effect on cellulose synthesis. However, all CesA mutants so far reported have been shown to be recessive in terms of cellulose synthesis. In the course of studying the molecular mechanisms regulating secondary wall formation in fibers, we have found that a mutant allele of AtCesA7 gene in the fra5 (fragile fiber 5) mutant causes a semidominant phenotype in the reduction of fiber cell wall thickness and cellulose content. The fra5 missense mutation occurred in a conserved amino acid located in the second cytoplasmic domain of AtCesA7. Overexpression of the fra5 mutant cDNA in wild-type plants not only reduced secondary wall thickness and cellulose content but also decreased primary wall thickness and cell elongation. In contrast, overexpression of the fra6 mutant form of AtCesA8 did not cause any reduction in cell wall thickness and cellulose content. These results suggest that the fra5 mutant protein may interfere with the function of endogenous wild-type CesA proteins, thus resulting in a dominant negative effect on cellulose biosynthesis.

  20. Fracture Surface Morphology and Impact Strength of Cellulose/PLA Composites

    Directory of Open Access Journals (Sweden)

    Honghong Gao

    2017-06-01

    Full Text Available Polylactide (PLA-based composite materials reinforced with ball-milled celluloses were manufactured by extrusion blending followed by injection molding. Their surface morphology from impact fracture were imaged with scanning electron microscopy (SEM and investigated by calculating their fractal dimensions. Then, linear regression was used to explore the relationship between fractal dimension and impact strength of the resultant cellulose/PLA composite materials. The results show that filling the ball-milled celluloses into PLA can improve the impact toughness of PLA by a minimum of 38%. It was demonstrated that the fracture pattern of the cellulose/PLA composite materials is different from that of pristine PLA. For the resultant composite materials, the fractal dimension of the impact fractured surfaces increased with increasing filling content and decreasing particle size of the ball-milled cellulose particles. There were highly positive correlations between fractal dimension of the fractured surfaces and impact strength of the cellulose/PLA composites. However, the linearity between fractal dimension and impact strength were different for the different methods, due to their different R-squared values. The approach presented in this work will help to understand the structure–property relationships of composite materials from a new perspective.

  1. CONTENTS

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The Development and Evolution of the Idea of the Mandate of Heaven in the Zhou Dynasty The changes in the idea of Mandate of Heaven during the Shang and Zhou dynasties are of great significance in the course of the development of traditional Chinese culture. The quickening and awakening of the humanistic spirit was not the entire content of the Zhou idea of Mandate of Heaven. In the process of annihilating the Shang dynasty and setting up their state, the Zhou propagated the idea of the Mandate of Heaven out of practical needs. Their idea of the Mandate of Heaven was not very different from that of the Shang. From the Western Zhou on, the Zhou idea of Mandate of Heaven by no means developed in a linear way along a rational track. The intermingling of rationality and irrationality and of awakening and non-awakening remained the overall state of the Zhou intellectual superstructure after their "spiritual awakening".

  2. [Effect of moisture content on anaerobic methanization of municipal solid waste].

    Science.gov (United States)

    Qu, Xian; He, Pin-Jing; Shao, Li-Ming; Bouchez, Théodore

    2009-03-15

    Biogas production, gas and liquid characteristics were investigated for comparing the effect of moisture content on methanization process of MSW with different compositions of food waste and cellulosic waste. Batch reactors were used to study the anaerobic methanization of typical Chinese and French municipal solid waste (MSW) and cellulosic waste with different moisture content, as 35%, field capacity (65%-70%), 80%, and saturated state (> 95%). The results showed that for the typical Chinese and French waste, which contained putrescible waste, the intermediate product, VFA, was diluted by high content of water, which helped to release the VFA inhibition on hydrolysis and methanization. Mass amount of methane was produced only when the moisture content of typical French waste was higher than 80%, while higher content of moisture was needed when the content of putrescible waste was higher in MSW, as > 95% for typical Chinese waste. Meanwhile the methane production rate and the ultimate cumulated methane production were increased when moisture content was leveled up. The ultimate cumulated methane production of the typical French waste with saturated state was 0.6 times higher than that of the waste with moisture content of 80%. For cellulosic waste, high moisture content of cellulosic materials contributed to increase the attachment area of microbes and enzyme on the surface of the materials, which enhance the waste hydrolysis and methanization. When the moisture content of the cellulosic materials increased from field capacity (65%) to saturated state (> 95%), the ultimate cumulated methane production increased for 3.8 times.

  3. Fabrication of polyaniline/carboxymethyl cellulose/cellulose nanofibrous mats and their biosensing application

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Jiapeng, E-mail: firgexiao@sina.cn; Pang, Zengyuan, E-mail: pangzengyuan1212@163.com; Yang, Jie, E-mail: young1993@126.com; Huang, Fenglin, E-mail: flhuang@jiangnan.edu.cn; Cai, Yibing, E-mail: yibingcai@jiangnan.edu.cn; Wei, Qufu, E-mail: qfwei@jiangnan.edu.cn

    2015-09-15

    Graphical abstract: - Highlights: • PANI nanorods have been grown onto the surface of CMC/cellulose nanofibers for the fabrication of biosensor substrate material. • The proposed laccase biosensor exhibited a low detection limit and high sensitivity in the detection of catechol. • Hierarchical PANI/CMC/cellulose nanofibers are the promising material in the design of high-efficient biosensors. - Abstract: We report a facile approach to synthesizing and immobilizing polyaniline nanorods onto carboxymethyl cellulose (CMC)-modified cellulose nanofibers for their biosensing application. Firstly, the hierarchical PANI/CMC/cellulose nanofibers were fabricated by in situ polymerization of aniline on the CMC-modified cellulose nanofiber. Subsequently, the PANI/CMC/cellulose nanofibrous mat modified with laccase (Lac) was used as biosensor substrate material for the detection of catechol. PANI/CMC/cellulose nanofibers with highly conductive and three dimensional nanostructure were characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), Fourier transform infrared spectra (FT-IR), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under optimum conditions, the Lac/PANI/CMC/cellulose/glassy carbon electrode (GCE) exhibited a fast response time (within 8 s), a linear response range from 0.497 μM to 2.27 mM with a high sensitivity and low detection limit of 0.374 μM (3σ). The developed biosensor also displayed good repeatability, reproducibility as well as selectivity. The results indicated that the composite mat has potential application in enzyme biosensors.

  4. An oral multispecies biofilm model for high content screening applications

    Science.gov (United States)

    Kommerein, Nadine; Stumpp, Sascha N.; Müsken, Mathias; Ehlert, Nina; Winkel, Andreas; Häussler, Susanne; Behrens, Peter; Buettner, Falk F. R.; Stiesch, Meike

    2017-01-01

    Peri-implantitis caused by multispecies biofilms is a major complication in dental implant treatment. The bacterial infection surrounding dental implants can lead to bone loss and, in turn, to implant failure. A promising strategy to prevent these common complications is the development of implant surfaces that inhibit biofilm development. A reproducible and easy-to-use biofilm model as a test system for large scale screening of new implant surfaces with putative antibacterial potency is therefore of major importance. In the present study, we developed a highly reproducible in vitro four-species biofilm model consisting of the highly relevant oral bacterial species Streptococcus oralis, Actinomyces naeslundii, Veillonella dispar and Porphyromonas gingivalis. The application of live/dead staining, quantitative real time PCR (qRT-PCR), scanning electron microscopy (SEM) and urea-NaCl fluorescence in situ hybridization (urea-NaCl-FISH) revealed that the four-species biofilm community is robust in terms of biovolume, live/dead distribution and individual species distribution over time. The biofilm community is dominated by S. oralis, followed by V. dispar, A. naeslundii and P. gingivalis. The percentage distribution in this model closely reflects the situation in early native plaques and is therefore well suited as an in vitro model test system. Furthermore, despite its nearly native composition, the multispecies model does not depend on nutrient additives, such as native human saliva or serum, and is an inexpensive, easy to handle and highly reproducible alternative to the available model systems. The 96-well plate format enables high content screening for optimized implant surfaces impeding biofilm formation or the testing of multiple antimicrobial treatment strategies to fight multispecies biofilm infections, both exemplary proven in the manuscript. PMID:28296966

  5. Development of automatic image analysis methods for high-throughput and high-content screening

    NARCIS (Netherlands)

    Di, Zi

    2013-01-01

    This thesis focuses on the development of image analysis methods for ultra-high content analysis of high-throughput screens where cellular phenotype responses to various genetic or chemical perturbations that are under investigation. Our primary goal is to deliver efficient and robust image analysis

  6. Development of automatic image analysis methods for high-throughput and high-content screening

    NARCIS (Netherlands)

    Di, Zi

    2013-01-01

    This thesis focuses on the development of image analysis methods for ultra-high content analysis of high-throughput screens where cellular phenotype responses to various genetic or chemical perturbations that are under investigation. Our primary goal is to deliver efficient and robust image analysis

  7. Electrically conductive cellulose composite

    Science.gov (United States)

    Evans, Barbara R.; O'Neill, Hugh M.; Woodward, Jonathan

    2010-05-04

    An electrically conductive cellulose composite includes a cellulose matrix and an electrically conductive carbonaceous material incorporated into the cellulose matrix. The electrical conductivity of the cellulose composite is at least 10 .mu.S/cm at 25.degree. C. The composite can be made by incorporating the electrically conductive carbonaceous material into a culture medium with a cellulose-producing organism, such as Gluconoacetobacter hansenii. The composites can be used to form electrodes, such as for use in membrane electrode assemblies for fuel cells.

  8. Mineralization of cellulose in frozen boreal soils

    Science.gov (United States)

    Oquist, Mats G.; Segura, Javier; Sparrman, Tobias; Nilsson, Mats; Schleucher, Jurgen

    2015-04-01

    Soils of high-latitude ecosystems store a large fraction of the global soil carbon. In boreal forests, the microbial mineralization of soil organic matter (SOM) during winter can affect the ecosystems net carbon balance. Recent research has shown that microorganisms in the organic surface layer of boreal forest soil can mineralize and grow on simple, soluble monomeric substrates under frozen conditions. However, any substantial impacts of microbial activity in frozen soils on long-term soil carbon balances ultimately depends on whether soil microorganisms can utilize and grow the more complex, polymeric constituents of SOM. In order to evaluate the potential for soil microorganisms to metabolize carbon polymers at low temperatures, we incubated boreal forest soil samples amended with [13C]-cellulose and studied the microbial catabolic and anabolic utilization of the substrate under frozen and unfrozen conditions (-4 and +4°C). Freezing of the soil markedly reduced microbial utilization of the cellulose. The [13C]-CO2 production rate in the samples at +4°C were 0.52 mg CO2 SOM -1 day-1 while rates in the frozen samples (-4°C) were 0.01 mg CO2 SOM -1 day-1. However, newly synthetized [13C]-enriched cell membrane lipids, PLFAs, were detected in soil samples incubated both above and below freezing, confirming that cellulose can sustain also anabolic activity of the microbial populations under frozen conditions. The reduced metabolic rates induced by freezing indicate constraints on exoenzymatic activity, as well as substrate diffusion rates that we can attribute to reduced liquid water content of the frozen soil. We conclude that the microbial population in boreal forest soil has the capacity to metabolize, and grow, on polymeric substrates at temperatures below zero, which involves maintaining exoenzymatic activity in frozen soils. This capacity manifests the importance of SOM mineralization during the winter season and its importance for the net carbon balance of

  9. Development of nonflammable cellulosic foams

    Science.gov (United States)

    Luttinger, M.

    1972-01-01

    The development of a moldable cellulosic foam for use in Skylab instrument storage cushions is considered. Requirements include density of 10 lb cu ft or less, minimal friability with normal handling, and nonflammability in an atmosphere of 70 percent oxygen and 30 percent nitrogen at 6.2 psia. A study of halogenated foam components was made, including more highly chlorinated binders, halogen-containing additives, and halogenation of the cellulose. The immediate objective was to reduce the density of the foam through reduction in inorganic phosphate without sacrificing flame-retarding properties of the foams. The use of frothing techniques was investigated, with particular emphasis on a urea-formaldehyde foam. Halogen-containing flame retardants were deemphasized in favor of inorganic salts and the preparation of phosphate and sulphate esters of cellulose. Utilization of foam products for civilian applications was also considered.

  10. Cellulolytic activity of some cellulose-decomposing fungi in salinized soils

    Directory of Open Access Journals (Sweden)

    R. A. Badran

    2014-08-01

    Full Text Available Maximum evolution of CO2 was marked in control soil inoculated by tested fungi but its rate decreased with the increasing salinity. The period of 10 days was most suitable for cellulose degradation by A. niger and P. chrysoecnum and 15 days by A. flavus and C. globosum in control soil. High salinity levels affected greatly the cellulolylic activities of tesled fungi. Carbon content of saline soils increased white the nitrogen content decreased.

  11. Utilization of industrial enzymes in the evaluation of neutral detergent insoluble fiber content in high-starch samples

    Directory of Open Access Journals (Sweden)

    Daiany Íris Gomes

    2014-09-01

    Full Text Available It were performed two experiments to evaluate the utilization of industrial enzymes in the evaluation of NDF contents in high-starch materials. In the first experiment, it was verified the accuracy of estimates of neutral detergent fiber (NDF obtained with the utilization of three industrial enzymes (Termamyl 2X, Liquozyme Supra 2.2.X, and Amylase AG 300L at different volumes (50, 100, 250 or 500 mL/ sample. Samples were simulated to contain starch at 0, 100, 300, 500 and 1000 g/kg using purified cellulose and starch (n = 240. In the second experiment, samples of corn grain and sorghum grain were evaluated considering the same enzyme types and volumes used in the first experiment adding aliquots without using enzyme (n = 104. There was no significant bias of NDF recovery for simulated samples containing starch up to 300 g/kg. Considering those samples, none difference among enzymes was observed. It was observed a more intense decrease in NDF content according to each enzyme unit added on corn when compared to sorghum. Considering NDF evaluation in samples with mass of 0.7 to 1.0 g, it can be recommended the utilization of 250 mL the ?-amylases Termamyl and 2X Liquozyme 2.2X with activities of 240 and 300 KNU/g, respectively.

  12. The importance of binder moisture content in Metformin HCL high-dose formulations prepared by moist aqueous granulation (MAG).

    Science.gov (United States)

    Takasaki, Hiroshi; Yonemochi, Etsuo; Ito, Masanori; Wada, Koichi; Terada, Katsuhide

    2015-01-01

    The aim of this study was to evaluate binders to improve the flowability of granulates and compactibility of Metformin HCL (Met) using the moist aqueous granulation (MAG) process. The effect of the binder moisture content on granulate and tablet quality was also evaluated. Vinylpyrrolidone-vinyl acetate copolymer (Kollidon VA64 fine: VA64), polyvidone (Povidone K12: PVP), hydroxypropyl cellulose (HPC SSL SF: HPC) and hydroxypropyl methylcellulose (Methocel E5 LV: HPMC) were evaluated as binders. These granulates, except for HPMC, had a lower yield pressure than Met active pharmaceutical ingredient (API). HPMC Met was not sufficiently granulated with low water volume. No problems were observed with the VA64 Met granulates during the tableting process. However, HPC Met granulates had a bowl-forming tendency, and PVP Met granulates had the tendency to stick during the tableting process. These bowl-forming and sticking tendencies may have been due to the low moisture absorbency of HPC and the high volume of bound water of PVP, respectively. VA64 Met granulates had the highest ambient moisture content (bulk water, bound water) and moisture absorbency. It was concluded that the type of binder used for the Met MAG process has an impact on granulate flow and compactibility, as well as moisture absorbency and maintenance of moisture balance.

  13. The importance of binder moisture content in Metformin HCL high-dose formulations prepared by moist aqueous granulation (MAG

    Directory of Open Access Journals (Sweden)

    Hiroshi Takasaki

    2015-01-01

    Full Text Available The aim of this study was to evaluate binders to improve the flowability of granulates and compactibility of Metformin HCL (Met using the moist aqueous granulation (MAG process. The effect of the binder moisture content on granulate and tablet quality was also evaluated. Vinylpyrrolidone–vinyl acetate copolymer (Kollidon VA64 fine: VA64, polyvidone (Povidone K12: PVP, hydroxypropyl cellulose (HPC SSL SF: HPC and hydroxypropyl methylcellulose (Methocel E5 LV: HPMC were evaluated as binders. These granulates, except for HPMC, had a lower yield pressure than Met active pharmaceutical ingredient (API. HPMC Met was not sufficiently granulated with low water volume. No problems were observed with the VA64 Met granulates during the tableting process. However, HPC Met granulates had a bowl-forming tendency, and PVP Met granulates had the tendency to stick during the tableting process. These bowl-forming and sticking tendencies may have been due to the low moisture absorbency of HPC and the high volume of bound water of PVP, respectively. VA64 Met granulates had the highest ambient moisture content (bulk water, bound water and moisture absorbency. It was concluded that the type of binder used for the Met MAG process has an impact on granulate flow and compactibility, as well as moisture absorbency and maintenance of moisture balance.

  14. Highly porous carbon from a natural cellulose fiber as high efficiency sorbent for lead in waste water.

    Science.gov (United States)

    Ilangovan, Manikandan; Guna, Vijaykumar; Olivera, Sharon; Ravi, Ashwini; Muralidhara, H B; Santosh, M S; Reddy, Narendra

    2017-08-24

    The persistence of hollow centre in the carbon obtained from milkweed floss provides exceptional sorption characteristics, not seen in common biomasses or their derivatives. A considerably high sorption of 320mg of lead per gram of milkweed carbon was achieved without any chemical modification to the biomass. In this research, we have carbonized milkweed floss and used the carbon as a sorbent for lead in waste water. A high surface area of 170m(2)g(-1) and pore volume of 1.07cm(3)g(-1) was seen in the carbon. Almost complete removal (>99% efficiency) of lead could be achieved within 5min when the concentration of lead in the solution was 100ppm, close to that prevailing in industrial waste water. SEM images showed that the carbon was hollow and confocal images confirmed that the sorbate could penetrate inside the hollow tube. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Flexible, highly graphitized carbon aerogels based on bacterial cellulose/lignin: Catalyst-free synthesis and its application in energy storage devices

    KAUST Repository

    Xu, Xuezhu

    2015-04-15

    Currently, most carbon aerogels are based on carbon nanotubes (CNTs) or graphene, which are produced through a catalyst-assisted chemical vapor deposition method. Biomass based organic aerogels and carbon aerogels, featuring low cost, high scalability, and small environmental footprint, represent an important new research direction in (carbon) aerogel development. Cellulose and lignin are the two most abundant natural polymers in the world, and the aerogels based on them are very promising. Classic silicon aerogels and available organic resorcinol-formaldehyde (RF) or lignin-resorcinol-formaldehyde (LRF) aerogels are brittle and fragile; toughening of the aerogels is highly desired to expand their applications. This study reports the first attempt to toughen the intrinsically brittle LRF aerogel and carbon aerogel using bacterial cellulose. The facile process is catalyst-free and cost-effective. The toughened carbon aerogels, consisting of blackberry-like, core-shell structured, and highly graphitized carbon nanofibers, are able to undergo at least 20% reversible compressive deformation. Due to their unique nanostructure and large mesopore population, the carbon materials exhibit an areal capacitance higher than most of the reported values in the literature. This property makes them suitable candidates for flexible solid-state energy storage devices. Besides energy storage, the conductive interconnected nanoporous structure can also find applications in oil/water separation, catalyst supports, sensors, and so forth. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Pre-irradiation grafting of cellulose and slightly carboxymethylated cellulose (CMC) fibres

    Energy Technology Data Exchange (ETDEWEB)

    Benke, N. [Institute of Isotopes, HAS, Budapest (Hungary); Takacs, E. [Institute of Isotopes, HAS, Budapest (Hungary)]. E-mail: takacs@iki.kfki.hu; Wojnarovits, L. [Institute of Isotopes, HAS, Budapest (Hungary); Borsa, J. [Budapest University of Technology and Economics, Budapest (Hungary)

    2007-08-15

    Acrylamide, hydroxypropyl acrylate, hydroxypropyl methacrylate and 2-ethylhexyl methacrylate vinyl monomers were grafted onto cellulose as well as onto cellulose of improved accessibility (slightly carboxymethylated cellulose (CMC)) by the pre-irradiation grafting technique. The effect of dose, monomer structure, crosslinking agent and carboxymethylation on the grafting yield was studied and the optimal conditions for the grafting were established. Grafting, with the exception of acrylamide (AAm), decreased the swelling of the samples, which is advantageous for some applications. In case of AAm decrease in swelling was observed only when crosslinking agent was applied. At low doses (<5 kGy) the high accessibility of carboxymethylated cellulose resulted in a higher grafting yield.

  17. Cellulose nanocrystals: synthesis, functional properties, and applications

    Directory of Open Access Journals (Sweden)

    George J

    2015-11-01

    Full Text Available Johnsy George, SN Sabapathi Food Engineering and Packaging Division, Defence Food Research Laboratory, Siddarthanagar, Mysore, Karnataka, India Abstract: Cellulose nanocrystals are unique nanomaterials derived from the most abundant and almost inexhaustible natural polymer, cellulose. These nanomaterials have received significant interest due to their mechanical, optical, chemical, and rheological properties. Cellulose nanocrystals primarily obtained from naturally occurring cellulose fibers are biodegradable and renewable in nature and hence they serve as a sustainable and environmentally friendly material for most applications. These nanocrystals are basically hydrophilic in nature; however, they can be surface functionalized to meet various challenging requirements, such as the development of high-performance nanocomposites, using hydrophobic polymer matrices. Considering the ever-increasing interdisciplinary research being carried out on cellulose nanocrystals, this review aims to collate the knowledge available about the sources, chemical structure, and physical and chemical isolation procedures, as well as describes the mechanical, optical, and rheological properties, of cellulose nanocrystals. Innovative applications in diverse fields such as biomedical engineering, material sciences, electronics, catalysis, etc, wherein these cellulose nanocrystals can be used, are highlighted. Keywords: sources of cellulose, mechanical properties, liquid crystalline nature, surface modification, nanocomposites 

  18. MWCNTs/Cellulose Hydrogels Prepared from NaOH/Urea Aqueous Solution with Improved Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Yingpu Zhang

    2015-01-01

    Full Text Available Novel high strength composite hydrogels were designed and synthesized by introducing multiwalled carbon nanotubes (MWCNTs into cellulose/NaOH/urea aqueous solution and then cross-linked by epichlorohydrin. MWCNTs were used to modify the matrix of cellulose. The structure and morphology of the hydrogels were characterized by Fourier transform infrared (FT-IR spectroscopy, high resolution transmission electron microscopy (HR-TEM, and scanning electron microscopy (SEM. The results from swelling testing revealed that the equilibrium swelling ratio of hydrogels decreased with the increment of MWCNTs content. Thermogravimetric analysis (TGA and dynamic mechanical analysis (DMA results demonstrated that the introduction of MWCNT into cellulose hydrogel networks remarkably improved both thermal and mechanical properties of the composite hydrogels. The preparation of MWCNTs modifiedcellulose-based composites with improved mechanical properties was the first important step towards the development of advanced functional materials.

  19. Cellulose nanofiber/nanocrystal reinforced capsules: a fast and facile approach toward assembly of liquid-core capsules with high mechanical stability.

    Science.gov (United States)

    Svagan, Anna J; Musyanovych, Anna; Kappl, Michael; Bernhardt, Max; Glasser, Gunnar; Wohnhaas, Christian; Berglund, Lars A; Risbo, Jens; Landfester, Katharina

    2014-05-12

    Liquid-core capsules of high mechanical stability open up for many solid state-like applications where functionality depending on liquid mobility is vital. Herein, a novel concept for fast and facile improvement of the mechanical properties of walls of liquid-core capsules is reported. By imitating nature's own way of enhancing the mechanical properties in liquid-core capsules, the parenchyma plant cells found in fruits and vegetables, a blend of short cellulose nanofibers (capsule walls. The NFC/CNC blend was prepared from a new version of the classical wood pulp hydrolysis. The capsule shell consisted of a covalently (by aromatic diisocyanate) cross-linked NFC/CNC structure at the outer capsule wall and an inner layer dominated by aromatic polyurea. The mechanical properties revealed an effective capsule elastic modulus of 4.8 GPa at 17 wt % NFC/CNC loading, about six times higher compared to a neat aromatic polyurea capsule (0.79 GPa) and 3 orders of magnitude higher than previously reported capsules from regenerated cellulose (0.0074 GPa). The outstanding mechanical properties are ascribed to the dense nanofiber structure, present in the outer part of the capsule wall, that is formed by oriented NFC/CNC of high average aspect ratio (L/d ∼ 70) and held together by both covalent (urethane bonds) and physical bonds (hydrogen bonds).

  20. Electrochemical Properties of LLTO/Fluoropolymer-Shell Cellulose-Core Fibrous Membrane for Separator of High Performance Lithium-Ion Battery

    Directory of Open Access Journals (Sweden)

    Fenglin Huang

    2016-01-01

    Full Text Available A superfine Li0.33La0.557TiO3 (LLTO, 69.4 nm was successfully synthesized by a facile solvent-thermal method to enhance the electrochemical properties of the lithium-ion battery separator. Co-axial nanofiber of cellulose and Poly(vinylidene fluoride-co-hexafluoropropylene (PVDF-HFP was prepared by a co-axial electrospinning technique, in which the shell material was PVDF-HFP and the core was cellulose. LLTO superfine nanoparticles were incorporated into the shell of the PVDF-HFP. The core–shell composite nanofibrous membrane showed good wettability (16.5°, contact angle, high porosity (69.77%, and super electrolyte compatibility (497%, electrolyte uptake. It had a higher ionic conductivity (13.897 mS·cm−1 than those of pure polymer fibrous membrane and commercial separator. In addition, the rate capability (155.56 mAh·g−1 was also superior to the compared separator. These excellent performances endowed LLTO composite nanofibrous membrane as a promising separator for high-performance lithium-ion batteries.

  1. Electrochemical Properties of LLTO/Fluoropolymer-Shell Cellulose-Core Fibrous Membrane for Separator of High Performance Lithium-Ion Battery.

    Science.gov (United States)

    Huang, Fenglin; Liu, Wenting; Li, Peiying; Ning, Jinxia; Wei, Qufu

    2016-01-26

    A superfine Li0.33La0.557TiO₃ (LLTO, 69.4 nm) was successfully synthesized by a facile solvent-thermal method to enhance the electrochemical properties of the lithium-ion battery separator. Co-axial nanofiber of cellulose and Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) was prepared by a co-axial electrospinning technique, in which the shell material was PVDF-HFP and the core was cellulose. LLTO superfine nanoparticles were incorporated into the shell of the PVDF-HFP. The core-shell composite nanofibrous membrane showed good wettability (16.5°, contact angle), high porosity (69.77%), and super electrolyte compatibility (497%, electrolyte uptake). It had a higher ionic conductivity (13.897 mS·cm(-1)) than those of pure polymer fibrous membrane and commercial separator. In addition, the rate capability (155.56 mAh·g(-1)) was also superior to the compared separator. These excellent performances endowed LLTO composite nanofibrous membrane as a promising separator for high-performance lithium-ion batteries.

  2. Electrochemical Properties of LLTO/Fluoropolymer-Shell Cellulose-Core Fibrous Membrane for Separator of High Performance Lithium-Ion Battery

    Science.gov (United States)

    Huang, Fenglin; Liu, Wenting; Li, Peiying; Ning, Jinxia; Wei, Qufu

    2016-01-01

    A superfine Li0.33La0.557TiO3 (LLTO, 69.4 nm) was successfully synthesized by a facile solvent-thermal method to enhance the electrochemical properties of the lithium-ion battery separator. Co-axial nanofiber of cellulose and Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) was prepared by a co-axial electrospinning technique, in which the shell material was PVDF-HFP and the core was cellulose. LLTO superfine nanoparticles were incorporated into the shell of the PVDF-HFP. The core–shell composite nanofibrous membrane showed good wettability (16.5°, contact angle), high porosity (69.77%), and super electrolyte compatibility (497%, electrolyte uptake). It had a higher ionic conductivity (13.897 mS·cm−1) than those of pure polymer fibrous membrane and commercial separator. In addition, the rate capability (155.56 mAh·g−1) was also superior to the compared separator. These excellent performances endowed LLTO composite nanofibrous membrane as a promising separator for high-performance lithium-ion batteries. PMID:28787873

  3. Influence of High Shear Dispersion on the Production of Cellulose Nanofibers by Ultrasound-Assisted TEMPO-Oxidation of Kraft Pulp

    Directory of Open Access Journals (Sweden)

    Claude Daneault

    2012-09-01

    Full Text Available Cellulose nanofibers can be produced using a combination of TEMPO, sodium bromide (NaBr and sodium hypochlorite, and mechanical dispersion. Recently, this process has been the subject of intensive investigation. However, studies on the aspects of mechanical treatment of this process remain marginal. The main objective of this study is to evaluate the high shear dispersion parameters (e.g., consistency, stator-rotor gap, recirculation rate and pH and determine their influences on nanocellulose production using ultrasound-assisted TEMPO-oxidation of Kraft pulp. All nanofiber gels produced in this study exhibited rheological behaviors known as shear thinning. From all the dispersion parameters, the following conditions were identified as optimal: 0.042 mm stator-rotor gap, 200 mL/min recycle rate, dispersion pH of 7 and a feed consistency of 2%. High quality cellulose gel could be produced under these conditions. This finding is surely of great interest for the pulp and paper industry.

  4. On the conflicting findings of Role of Cellulose-Crystallinity in Enzume Hydrolysis of Biomass

    Science.gov (United States)

    Umesh Agarwal; Sally Ralph

    2014-01-01

    In the field of conversion of biomass to ethanol, an important area of research is the enzymatic hydrolysis of cellulose. Once cellulose is converted to glucose, it can be easily fermented to ethanol. As the cellulosic ethanol technology stands now, costly pretreatments and high dosages of cellulases are needed to achieve complete hydrolysis of the cellulose fraction...

  5. Influence of HNO3/H3PO4-NANO2 mediated oxidation on the structure and properties of cellulose fibers.

    Science.gov (United States)

    Xu, Yunhui; Liu, Xin; Liu, Xuelan; Tan, Jiulong; Zhu, Hongling

    2014-10-13

    The bamboo pulp cellulose fiber was oxidized with HNO3/H3PO4-NaNO2 mixture to obtain oxidized cellulose containing different levels of carboxyl content and with high yields. The effects of HNO3/H3PO4-NaNO2 mediated oxidation on structure and properties of the fiber were investigated. The results showed that an increase in carboxyl content and weight loss of oxidized fibers appeared with increasing oxidation time. Compared with the original cellulose, the oxidized fibers had lower crystallinity (29-40%) and thermal stability. The patterns of (13)C NMR, X-ray diffraction and other testing methods revealed that the oxidation mostly occurred at C6 primary hydroxyl groups of cellulose. Moreover, an oxidized fiber with 94.14-98.59% of high yields and 1.13-3.56% of carboxyl content was obtained in the range of oxidation time from 15 to 60 min, while its mechanical properties did not change significantly. This work presented some detailed information about structure-property correlations of oxidized bamboo pulp cellulose fibers and was useful in planning applications of these products.

  6. STUDY ADSORPTION DESORPTION OF MANGANESE(II USING IMPREGNATED CHITIN-CELLULOSE AS ADSORBENT

    Directory of Open Access Journals (Sweden)

    Aldes Lesbani

    2015-03-01

    Full Text Available Abstract- Study adsorption desorption of manganese(II using impregnated chitin-cellulose as adsorbent has been carried out. Chitin was extracted from snail shell and cellulose isolated from rice straw. Chitin and cellulose were impregnated using thiourea as impregnant agent. Characterization of chitin and cellulose was performed using FTIR spectroscopy, determination of water content, and ash content, while impregnated chitin-cellulose was characterized using FTIR spectrophotometer and X-Ray diffractometer. The adsorption of Mn(II on impregnated chitin-cellulose was studied through determination of adsorption time and the influence of Mn(II concentration, while desorption was carried out sequentially using various reagents. The results shown that chitin and cellulose from extraction processes are has similar FTIR spectrum compared to chitin and cellulose standard. The FTIR spectrum of impregnated chitin-cellulose shows both vibration of chitin and cellulose appeared and indicated successfully impregnate. These results were also equal to XRD pattern analysis. The water and ash contents of chitin are 0.038% and 0.043 while for cellulose are 0.184% and 0.165%, respectively. The adsorption of Mn(II on chitin and cellulose are quite similar kinetically, while adsorption of Mn(II on impregnated chitin-cellulose is higher at the same time with chitin and cellulose. In the low concentration of Mn(II, adsorption phenomena are similar on chitin, cellulose, and impregnated chitin-cellulose. Desorption process of Mn(II on the adsorbents shows sodium etilenediamine tetra acetate able to desorp Mn(II up to 68% higher than other reagents. Keywords: Manganese(II, Chitin, Cellulose, Impregnated Chitin-Cellulose

  7. Optimizing Extraction of Cellulose and Synthesizing Pharmaceutical Grade Carboxymethyl Sago Cellulose from Malaysian Sago Pulp

    Directory of Open Access Journals (Sweden)

    Anand Kumar Veeramachineni

    2016-06-01

    Full Text Available Sago biomass is an agro-industrial waste produced in large quantities, mainly in the Asia-Pacific region and in particular South-East Asia. This work focuses on using sago biomass to obtain cellulose as the raw material, through chemical processing using acid hydrolysis, alkaline extraction, chlorination and bleaching, finally converting the material to pharmaceutical grade carboxymethyl sago cellulose (CMSC by carboxymethylation. The cellulose was evaluated using Thermogravimetric Analysis (TGA, Infrared Spectroscopy (FTIR, X-Ray Diffraction (XRD, Differential Scanning Calorimetry (DSC and Field Emission Scanning Electronic Microscopy (FESEM. The extracted cellulose was analyzed for cellulose composition, and subsequently modified to CMSC with a degree of substitution (DS 0.6 by typical carboxymethylation reactions. X-ray diffraction analysis indicated that the crystallinity of the sago cellulose was reduced after carboxymethylation. FTIR and NMR studies indicate that the hydroxyl groups of the cellulose fibers were etherified through carboxymethylation to produce CMSC. Further characterization of the cellulose and CMSC were performed using FESEM and DSC. The purity of CMSC was analyzed according to the American Society for Testing and Materials (ASTM International standards. In this case, acid and alkaline treatments coupled with high-pressure defibrillation were found to be effective in depolymerization and defibrillation of the cellulose fibers. The synthesized CMSC also shows no toxicity in the cell line studies and could be exploited as a pharmaceutical excipient.

  8. Production and effect of aldonic acids during enzymatic hydrolysis of lignocellulose at high dry matter content

    OpenAIRE

    Cannella David; Hsieh Chia-wen C; Felby Claus; Jørgensen Henning

    2012-01-01

    Abstract Background The recent discovery of accessory proteins that boost cellulose hydrolysis has increased the economical and technical efficiency of processing cellulose to bioethanol. Oxidative enzymes (e.g. GH61) present in new commercial enzyme preparations have shown to increase cellulose conversion yields. When using pure cellulose substrates it has been determined that both oxidized and unoxidized cellodextrin products are formed. We report the effect of oxidative activity in a comme...

  9. Production and effect of aldonic acids during enzymatic hydrolysis of lignocellulose at high dry matter content

    OpenAIRE

    Cannella, David; Hsieh, Chia-wen C; Felby, Claus; Jørgensen, Henning

    2012-01-01

    Background The recent discovery of accessory proteins that boost cellulose hydrolysis has increased the economical and technical efficiency of processing cellulose to bioethanol. Oxidative enzymes (e.g. GH61) present in new commercial enzyme preparations have shown to increase cellulose conversion yields. When using pure cellulose substrates it has been determined that both oxidized and unoxidized cellodextrin products are formed. We report the effect of oxidative activity in a commercial enz...

  10. Characterization of cellulose nanowhiskers; Caracterizacao do nanowhiskers de celulose

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Nayra R.; Pinheiro, Ivanei F.; Morales, Ana R.; Ravagnani, Sergio P.; Mei, Lucia, E-mail: 25nareis@gmail.com [Universidade Estadual de Campinas (UNICAMP), SP (Brazil)

    2013-07-01

    Cellulose is the most abundant polymer earth. The cellulose nanowhiskers can be extracted from the cellulose. These have attracted attention for its use in nanostructured materials for various applications, such as nanocomposites, because they have peculiar characteristics, among them, high aspect ratio, biodegradability and excellent mechanical properties. This work aims to characterize cellulose nanowhiskers from microcrystalline cellulose. Therefore, these materials were characterized by X-ray diffraction (XRD) to assess the degree of crystallinity, infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) to the morphology of nanowhiskers and thermal stability was evaluated by Thermogravimetric Analysis (TGA). (author)

  11. Synthesis and electrospinning carboxymethyl cellulose lithium (CMC-Li) modified 9,10-anthraquinone (AQ) high-rate lithium-ion battery.

    Science.gov (United States)

    Qiu, Lei; Shao, Ziqiang; Liu, Minglong; Wang, Jianquan; Li, Pengfa; Zhao, Ming

    2014-02-15

    New cellulose derivative CMC-Li was synthesized, and nanometer CMC-Li fiber was applied to lithium-ion battery and coated with AQ by electrospinning. Under the protection of inert gas, modified AQ/carbon nanofibers (CNF)/Li nanometer composite material was obtained by carbonization in 280 °C as lithium battery anode materials for the first time. The morphologies and structures performance of materials were characterized by using IR, (1)H NMR, SEM, CV and EIS, respectively. Specific capacity was increased from 197 to 226.4 mAhg(-1) after modification for the first discharge at the rate of 2C. Irreversible reduction reaction peaks of modified material appeared between 1.5 and 1.7 V and the lowest oxidation reduction peak of the difference were 0.42 V, the polarization was weaker. Performance of cell with CMC-Li with the high degree of substitution (DS) was superior to that with low DS. Cellulose materials were applied to lithium battery to improve battery performance by electrospinning. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Cellulose Breakdown

    Science.gov (United States)

    Greenler, John; Nye, Leith; Tangen, Travis

    2014-01-01

    Production of liquid fuels such as ethanol from fibrous plant biomass could potentially be a significant sustainable component of the U.S. energy portfolio. Engineers and scientists are actively researching this area, and high school students can engage in this contemporary inquiry process by experimenting with different types of biomass, varying…

  13. An objective method for High Dynamic Range source content selection

    DEFF Research Database (Denmark)

    Narwaria, Manish; Mantel, Claire; Da Silva, Matthieu Perreira

    2014-01-01

    component of such validation studies is the selection of a challenging and balanced set of source (reference) HDR content. In order to facilitate this, we present an objective method based on the premise that a more challenging HDR scene encapsulates higher contrast, and as a result will show up more...

  14. 基于近红外技术的苎麻纤维素及胶质含量快速测定%Fast quantitative analysis of cellulose and gum content in ramie based on near-infrared technique

    Institute of Scientific and Technical Information of China (English)

    姜伟; 韩光亭; 张元明; 陈建华

    2012-01-01

    As ramie is an important cellulose raw material in textile industry in China, a fast and accurate analysis method is required to determine its chemical composition. In this research, calibration models were established using near-infrared (NIR) spectroscopy assisted with partial least square (PLS) to predict the main chemical composition of ramie based on the prior work using an acousto-optic tunable filter ( AOTF) near infrared spectrograph, and the thickness of samples affecting calibration model was also discussed. Results show that the average relative errors ( AREs) of cellulose and gum content between the predicted value and the measured value were 1.11% and 4. 54% , respectively, which were low enough for prediction. Meanwhile, the thicker the sample, the more accurate the NIR model to prediction.%苎麻作为我国重要纺织用纤维素纤维资源,常需对其化学成分进行定量分析,因此需要一种快速高效的定量分析手段.在前期工作的基础上,使用AOTF近红外光谱仪,利用近红外漫反射光谱(NIR)技术,采用偏最小二乘法(PLS),并对比近红外样品厚度对建模的影响,建立了苎麻纤维素及胶质含量的NIR校正模型.实验结果表明:所建苎麻NIR模型对纤维素含量预测的平均相对误差为1.11%,胶质含量预测的平均相对误差为4.54%,预测值与化学值误差较小,故可以用于苎麻纤维素及胶质含量的预测.同时发现,样品厚度越大,扫描得到光谱所建模型预测精确度越高.

  15. Characterization of Cellulose Microfibers Isolated from Rubberwood (Hevea brasiliensis

    Directory of Open Access Journals (Sweden)

    Junidah Lamaming

    2016-03-01

    Full Text Available Cellulose microfibers were isolated by chemical treatment followed by acid hydrolysis using sulphuric acid. The chemical compositions for extractive, holocellulose, cellulose and lignin were determined. The functional group of raw particles and cellulose microfibers of rubberwood were determined using fourier transform infrared spectroscopy (FT-IR. Morphological studies were viewed using Scanning Electron Microscopy (SEM to investigate physical changes of the fibers after acid hydrolysis. The results show that cellulose content was increased to 63 % from 52 % after hydrolysis was conducted to the raw particles. Particle size distribution of cellulose microfibers falls in the range of below 100 µm. The removal of lignin and other extractives during chemical and acid hydrolysis can be seen by the absence of certain band in the FTIR spectra. The individualization of the fibers can be seen after hydrolysis with sulphuric acid. The removal of the surface impurities along with defibrillation were also shown in the cellulose microfibers. Cellulose microfibers were isolated by chemical treatment followed by acid hydrolysis using sulphuric acid. The chemical compositions for extractive, holocellulose, cellulose and lignin were determined. The functional group of raw particles and cellulose microfibers of rubberwood were determined using fourier transform infrared spectroscopy (FT-IR. Morphological studies were viewed using Scanning Electron Microscopy (SEM to investigate physical changes of the fibers after acid hydrolysis. The results show that cellulose content was increased to 63 % from 52 % after hydrolysis was conducted to the raw particles. Particle size distribution of cellulose microfibers falls in the range of below 100 µm. The removal of lignin and other extractives during chemical and acid hydrolysis can be seen by the absence of certain band in the FTIR spectra. The individualization of the fibers can be seen after hydrolysis with

  16. [Dietary fiber content of diets of the Don Basin population].

    Science.gov (United States)

    Artemov, A A; Vankhanen, V V; Kovalenko, A A

    1984-01-01

    It has been demonstrated that the total content of food fibers in the daily diet of the Donbas population diets amounts to 24.0-26.3 g (cellulose 5.9-6.7 g, pectin 2.0-2.7 g, hemicellulose 16.1-16.9 g). Baked goods account for the major part of hemicellulose (about 85%) and 1/3 of cellulose. Potato and vegetables (fruit) account for half of pectin and 1/3 of cellulose. The daily requirement of cellulose and pectin was satisfied by about 1/3, which is accounted for by a high relative significance of refined products (about 60% of the diet caloric value).

  17. Investigation of the physico-mechanical properties of electrospun PVDF/cellulose nanofibers.

    OpenAIRE

    Issa, A. A. [احمد عبد السلام عيسى; Al-Maadeed, M.; Luyt,A.S.; Mrlik, M.; Hassan, M. K.

    2016-01-01

    The electro-activity and mechanical properties of PVDF depends mainly on the b-phase content and degree of crystallinity. In this study, cellulose fibers were used to improve these characteristics. This could be achieved because the hydroxyl groups on cellulose would force the fluorine atoms in PVDF to be in the trans-conformation, and the cellulose particles could act as nucleation centers. Electrospinning was used to prepare the PVDF/cellulose (nano)fibrous films, and this improved the tota...

  18. Cellulose Degradation by Cellulose-Clearing and Non-Cellulose-Clearing Brown-Rot Fungi

    OpenAIRE

    Highley, Terry L.

    1980-01-01

    Cellulose degradation by four cellulose-clearing brown-rot fungi in the Coniophoraceae—Coniophora prasinoides, C. puteana, Leucogyrophana arizonica, and L. olivascens—is compared with that of a non-cellulose-clearing brown-rot fungus, Poria placenta. The cellulose- and the non-cellulose-clearing brown-rot fungi apparently employ similar mechanisms to depolymerize cellulose; most likely a nonenzymatic mechanism is involved.

  19. Biogenic nanosilica blended by nanofibrillated cellulose as support for slow-release of tebuconazole

    Science.gov (United States)

    Mattos, Bruno D.; Magalhães, Washington L. E.

    2016-09-01

    Despite the potential application of nanotechnology in the agricultural sector, it is not as competitive as other industrial sectors because these approaches do not demonstrate a sufficient economic return to counterbalance the high production costs. For biocidal purposes, the reduction of the initial costs can be addressed if biogenic nanosilica and nanofibrillated cellulose were used to prepare nanocomposite for further utilization as support for slow-release of tebuconazole. Infrared spectroscopy and thermogravimetric analysis revealed that biocide was entrapped in the cellulose/silica nanocomposites network. The scanning electron microscopy and X-ray microtomography evaluation showed the nanocomposite's microstructure based on irregular shape nanosilica blended by nanofibrillated cellulose in a randomly organized network. Elemental mapping images showed the tebuconazole better dispersed in the composite blended with lower content of cellulose. The nanofibrillated cellulose played an important role in the release rate of the biocide mainly at short-term periods. At 15 days of immersion, the pure biocide had 95 % release compared with 30-45 % release of the tebuconazole loaded in the nanocomposites.

  20. Physicochemical characterization of novel Schiff bases derived from developed bacterial cellulose 2,3-dialdehyde.

    Science.gov (United States)

    Keshk, Sherif M A S; Ramadan, Ahmed M; Bondock, Samir

    2015-08-20

    The synthesis of two novel Schiff's bases (cellulose-2,3-bis-[(4-methylene-amino)-benzene-sulfonamide] (5) & cellulose-2,3-bis-[(4-methylene-amino)-N-(thiazol-2-yl)-benzenesulfonamide] (6) via condensation reactions of periodate oxidized developed bacterial cellulose ODBC (2) with sulfa drugs [sulfanilamide (3) & sulfathiazole (4)] was reported. The physicochemical characterization of the condensation products was performed using FTIR, (1)H NMR, (13)C NMR spectral analyses, X-ray diffraction and DTA. The ODBC exhibited the highest degree of oxidation based on the aldehyde group number percentage (82.9%), which confirms the highest reactivity of developed bacterial cellulose [DBC (1)]. The X-ray diffractograms indicated an increase in the interplanar distance of the cellulose Schiff base (6) compared to ODBC (2) due to sulfathiazole (4) inclusion between ODBC (2) sheets corresponding to the 1 1 0 plane. In addition, the aldehyde content of Schiff base (6) was (20.8%) much lower than that of Schiff base (5) (41.5%). These results confirmed the high affinity of sulfathiazole (4) to the ODBC (2) chain, and the substantial changes in the original properties of ODBC were due to these chemical modifications rather than the sulfanilamide (3).

  1. Influence of Water on the Structure and Dielectric Properties of the Microcrystalline and Nano-Cellulose

    Science.gov (United States)

    Kovalov, Kostiantyn M.; Alekseev, Olexander M.; Lazarenko, Maxim M.; Zabashta, Yu F.; Grabovskii, Yurii E.; Tkachov, Sergii Yu

    2017-07-01

    Influence of water in the different states on a structure and dielectric properties of microcrystalline cellulose were studied by of X-ray, thermogravimetry, and dielectric spectroscopy. At research of microcrystalline cellulose (MCC) with different content of water, it is shown that the molecules of water are located in the macropores of MCC and in multimolecular hydrated layers. It is shown that at the increase of concentration of water in a hydrated shell, the reorganization of molecules of cellulose in the surface of crystallites takes place, and as a result, their transversal size and crystallinity increase. It is shown that during the concentration of water, more than 13% in a continuous hydrated shell of crystallites appears. Temperature dependences of actual and imaginary parts of complex dielectric permittivity were studied in the interval of temperatures [-180 ÷ 120] °C on frequencies of f = 5, 10, 20, and 50 kHz. A low-temperature relaxation process and high-temperature transition were observed. Low-temperature relaxation process which is related to transition of surface methylol groups of molecules of cellulose conformation from tg to tt is shifted toward low temperatures at the increase of concentration of water in microcrystalline cellulose.

  2. Normal and polar-organic-phase high-performance liquid chromatographic enantioresolution of omeprazole, rabeprazole, lansoprazole and pantoprazole using monochloro-methylated cellulose-based chiral stationary phase and determination of dexrabeprazole.

    Science.gov (United States)

    Dixit, Shuchi; Dubey, Rituraj; Bhushan, Ravi

    2014-01-01

    Enantioresolution of four anti-ulcer drugs (chiral sulfoxides), namely, omeprazole, rabeprazole, lansoprazole and pantoprazole, was carried out by high-performance liquid chromatography using a polysaccharide-based chiral stationary phase consisting of monochloromethylated cellulose (Lux cellulose-2) under normal and polar-organic-phase conditions with ultraviolet detection at 285 nm. The method was validated for linearity, accuracy, precision, robustness and limit of detection. The optimized enantioresolution method was compared for both the elution modes. The optimized method was further utilized to check the enantiomeric purity of dexrabeprazole.

  3. Reactive Liftoff of Crystalline Cellulose Particles

    Science.gov (United States)

    Teixeira, Andrew R.; Krumm, Christoph; Vinter, Katherine P.; Paulsen, Alex D.; Zhu, Cheng; Maduskar, Saurabh; Joseph, Kristeen E.; Greco, Katharine; Stelatto, Michael; Davis, Eric; Vincent, Brendon; Hermann, Richard; Suszynski, Wieslaw; Schmidt, Lanny D.; Fan, Wei; Rothstein, Jonathan P.; Dauenhauer, Paul J.

    2015-06-01

    The condition of heat transfer to lignocellulosic biomass particles during thermal processing at high temperature (>400 °C) dramatically alters the yield and quality of renewable energy and fuels. In this work, crystalline cellulose particles were discovered to lift off heated surfaces by high speed photography similar to the Leidenfrost effect in hot, volatile liquids. Order of magnitude variation in heat transfer rates and cellulose particle lifetimes was observed as intermediate liquid cellulose droplets transitioned from low temperature wetting (500-600 °C) to fully de-wetted, skittering droplets on polished surfaces (>700 °C). Introduction of macroporosity to the heated surface was shown to completely inhibit the cellulose Leidenfrost effect, providing a tunable design parameter to control particle heat transfer rates in industrial biomass reactors.

  4. Reactive Liftoff of Crystalline Cellulose Particles.

    Science.gov (United States)

    Teixeira, Andrew R; Krumm, Christoph; Vinter, Katherine P; Paulsen, Alex D; Zhu, Cheng; Maduskar, Saurabh; Joseph, Kristeen E; Greco, Katharine; Stelatto, Michael; Davis, Eric; Vincent, Brendon; Hermann, Richard; Suszynski, Wieslaw; Schmidt, Lanny D; Fan, Wei; Rothstein, Jonathan P; Dauenhauer, Paul J

    2015-06-09

    The condition of heat transfer to lignocellulosic biomass particles during thermal processing at high temperature (>400 °C) dramatically alters the yield and quality of renewable energy and fuels. In this work, crystalline cellulose particles were discovered to lift off heated surfaces by high speed photography similar to the Leidenfrost effect in hot, volatile liquids. Order of magnitude variation in heat transfer rates and cellulose particle lifetimes was observed as intermediate liquid cellulose droplets transitioned from low temperature wetting (500-600 °C) to fully de-wetted, skittering droplets on polished surfaces (>700 °C). Introduction of macroporosity to the heated surface was shown to completely inhibit the cellulose Leidenfrost effect, providing a tunable design parameter to control particle heat transfer rates in industrial biomass reactors.

  5. High water content in primitive continental flood basalts

    Science.gov (United States)

    Xia, Qun-Ke; Bi, Yao; Li, Pei; Tian, Wei; Wei, Xun; Chen, Han-Lin

    2016-01-01

    As the main constituent of large igneous provinces, the generation of continental flood basalts (CFB) that are characterized by huge eruption volume (>105 km3) within short time span (basaltic melts and the partition coefficient of H2O between cpx and basaltic melt. The arc-like H2O content (4.82 ± 1.00 wt.%) provides the first clear evidence that H2O plays an important role in the generation of CFB. PMID:27143196

  6. Decomposition kinetics of expanded austenite with high nitrogen contents

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Somers, Marcel A. J.

    2006-01-01

    This paper addresses the decomposition kinetics of synthesized homogeneous expanded austenite formed by gaseous nitriding of stainless steel AISI 304L and AISI 316L with nitrogen contents up to 38 at.% nitrogen. Isochronal annealing experiments were carried out in both inert (N2) and reducing (H2......) atmospheres. Differential thermal analysis (DTA) and thermogravimetry were applied for identification of the decomposition reactions and X-ray diffraction analysis was applied for phase analysis. CrN precipitated upon annealing; the activation energies are 187 kJ/mol and 128 kJ/mol for AISI 316L and AISI 304L...

  7. Cellulose-water interaction: a spectroscopic study

    OpenAIRE

    Lindh, Erik L

    2016-01-01

    The human society of today has a significantly negative impact on the environment and needs to change its way of living towards a more sustainable path if to continue to live on a healthy planet. One path is believed to be an increased usage of naturally degradable and renewable raw materials and, therefore, attention has been focused on the highly abundant biopolymer cellulose. However, a large drawback with cellulose-based materials is the significant change of their mechanical properties w...

  8. Water Availability as a Measure of Cellulose Hydrolysis Efficiency

    DEFF Research Database (Denmark)

    Hsieh, Chia-Wen

    of sugars, salts, and surfactants impact the water relaxation time. Systems with high concentrations of sugars and salts tend to have low water availability, as these form strong interactions with water to keep their solubility, leaving less water available for hydrolysis. Thus, cellulase performance...... to measure properties of the liquid phase, where water protons are characterized based on their mobility in the system as measured by their relaxation time. Studies of cellulose hydrolysis at low dry matter show that the contents of the liquid phase influence the final hydrolysis yield, as the presence...

  9. Plasma-enhanced synthesis of green flame retardant cellulosic materials

    Science.gov (United States)

    Totolin, Vladimir

    The natural fiber-containing fabrics and composites are more environmentally friendly, and are used in transportation (automobiles, aerospace), military applications, construction industries (ceiling paneling, partition boards), consumer products, etc. Therefore, the flammability characteristics of the composites based on polymers and natural fibers play an important role. This dissertation presents the development of plasma assisted - green flame retardant coatings for cellulosic substrates. The overall objective of this work was to generate durable flame retardant treatment on cellulosic materials. In the first approach sodium silicate layers were pre-deposited onto clean cotton substrates and cross linked using low pressure, non-equilibrium oxygen plasma. A statistical design of experiments was used to optimize the plasma parameters. The modified cotton samples were tested for flammability using an automatic 45° angle flammability test chamber. Aging tests were conducted to evaluate the coating resistance during the accelerated laundry technique. The samples revealed a high flame retardant behavior and good thermal stability proved by thermo-gravimetric analysis. In the second approach flame retardant cellulosic materials have been produced using a silicon dioxide (SiO2) network coating. SiO 2 network armor was prepared through hydrolysis and condensation of the precursor tetraethyl orthosilicate (TEOS), prior coating the substrates, and was cross linked on the surface of the substrates using atmospheric pressure plasma (APP) technique. Due to protection effects of the SiO2 network armor, the cellulosic based fibers exhibit enhanced thermal properties and improved flame retardancy. In the third approach, the TEOS/APP treatments were extended to linen fabrics. The thermal analysis showed a higher char content and a strong endothermic process of the treated samples compared with control ones, indicating a good thermal stability. Also, the surface analysis proved

  10. Determination of Stabiliser Contents in Advanced Gun Propellants by Reverse Phase High Performance Liquid Chromatography

    Science.gov (United States)

    1994-03-01

    HIGH PERFORMANCE LIQUID CHROMATOGRAPHY N"m A.R. TURNER AND A. WHITE...TO biEPROOU.; AND SELL THIS REPORT Determination of Stabiliser Contents in Advanced Gun Propellants by Reverse Phase High Performance Liquid Chromatography A.R...8217/......... .. Availability Cooes Dist Avaiardlo A-i Determination of Stabiliser Contents in Advanced Gun Propellants by Reverse Phase High Performance Liquid Chromatography

  11. Electric-arc synthesis of soot with high content of higher fullerenes in parallel arc

    Science.gov (United States)

    Dutlov, A. E.; Nekrasov, V. M.; Sergeev, A. G.; Bubnov, V. P.; Kareev, I. E.

    2016-12-01

    Soot with a relatively high content of higher fullerenes (C76, C78, C80, C82, C84, C86, etc.) is synthesized in a parallel arc upon evaporation of pure carbon electrodes. The content of higher fullerenes in soot extract amounts to 13.8 wt % when two electrodes are simultaneously burnt in electric-arc reactor. Such a content is comparable with the content obtained upon evaporation of composite graphite electrodes with potassium carbonate impurity.

  12. Polyimide Cellulose Nanocrystal Composite Aerogels

    Science.gov (United States)

    Nguyen, Baochau N.; Meador, Mary Ann; Rowan, Stuart; Cudjoe, Elvis; Sandberg, Anna

    2014-01-01

    Polyimide (PI) aerogels are highly porous solids having low density, high porosity and low thermal conductivity with good mechanical properties. They are ideal for various applications including use in antenna and insulation such as inflatable decelerators used in entry, decent and landing operations. Recently, attention has been focused on stimuli responsive materials such as cellulose nano crystals (CNCs). CNCs are environmentally friendly, bio-renewable, commonly found in plants and the dermis of sea tunicates, and potentially low cost. This study is to examine the effects of CNC on the polyimide aerogels. The CNC used in this project are extracted from mantle of a sea creature called tunicates. A series of polyimide cellulose nanocrystal composite aerogels has been fabricated having 0-13 wt of CNC. Results will be discussed.

  13. High content screening as high quality assay for biological evaluation of photosensitizers in vitro.

    Directory of Open Access Journals (Sweden)

    Gisela M F Vaz

    Full Text Available A novel single step assay approach to screen a library of photdynamic therapy (PDT compounds was developed. Utilizing high content analysis (HCA technologies several robust cellular parameters were identified, which can be used to determine the phototoxic effects of porphyrin compounds which have been developed as potential anticancer agents directed against esophageal carcinoma. To demonstrate the proof of principle of this approach a small detailed study on five porphyrin based compounds was performed utilizing two relevant esophageal cancer cell lines (OE21 and SKGT-4. The measurable outputs from these early studies were then evaluated by performing a pilot screen using a set of 22 compounds. These data were evaluated and validated by performing comparative studies using a traditional colorimetric assay (MTT. The studies demonstrated that the HCS assay offers significant advantages over and above the currently used methods (directly related to the intracellular presence of the compounds by analysis of their integrated intensity and area within the cells. A high correlation was found between the high content screening (HCS and MTT data. However, the HCS approach provides additional information that allows a better understanding of the behavior of these compounds when interacting at the cellular level. This is the first step towards an automated high-throughput screening of photosensitizer drug candidates and the beginnings of an integrated and comprehensive quantitative structure action relationship (QSAR study for photosensitizer libraries.

  14. Isolation of cellulose microfibrils - An enzymatic approach

    Directory of Open Access Journals (Sweden)

    Sain, M.

    2006-11-01

    Full Text Available Isolation methods and applications of cellulose microfibrils are expanding rapidly due to environmental benefits and specific strength properties, especially in bio-composite science. In this research, we have success-fully developed and explored a novel bio-pretreatment for wood fibre that can substantially improve the microfibril yield, in comparison to current techniques used to isolate cellulose microfibrils. Microfibrils currently are isolated in the laboratory through a combination of high shear refining and cryocrushing. A high energy requirement of these procedures is hampering momentum in the direction of microfibril isolation on a sufficiently large scale to suit potential applications. Any attempt to loosen up the microfibrils by either complete or partial destruction of the hydrogen bonds before the mechanical process would be a step forward in the quest for economical isolation of cellulose microfibrils. Bleached kraft pulp was treated with OS1, a fungus isolated from Dutch Elm trees infected with Dutch elm disease, under different treatment conditions. The percentage yield of cellulose microfibrils, based on their diameter, showed a significant shift towards a lower diameter range after the high shear refining, compared to the yield of cellulose microfibrils from untreated fibres. The overall yield of cellulose microfibrils from the treated fibres did not show any sizeable decrease.

  15. Pedagogical content knowledge and preparation of high school physics teachers

    Directory of Open Access Journals (Sweden)

    Eugenia Etkina

    2010-08-01

    Full Text Available This paper contains a scholarly description of pedagogical practices of the Rutgers Physics/Physical Science Teacher Preparation program. The program focuses on three aspects of teacher preparation: knowledge of physics, knowledge of pedagogy, and knowledge of how to teach physics (pedagogical content knowledge—PCK. The program has been in place for 7 years and has a steady production rate of an average of six teachers per year who remain in the profession. The main purpose of the paper is to provide information about a possible structure, organization, and individual elements of a program that prepares physics teachers. The philosophy of the program and the coursework can be implemented either in a physics department or in a school of education. The paper provides details about the program course work and teaching experiences and suggests ways to adapt it to other local conditions.

  16. Biocompatible cellulose-based superabsorbent hydrogels with antimicrobial activity.

    Science.gov (United States)

    Peng, Na; Wang, Yanfeng; Ye, Qifa; Liang, Lei; An, Yuxing; Li, Qiwei; Chang, Chunyu

    2016-02-10

    Current superabsorbent hydrogels commercially applied in the disposable diapers have disadvantages such as weak mechanical strength, poor biocompatibility, and lack of antimicrobial activity, which may induce skin allergy of body. To overcome these hassles, we have developed novel cellulose based hydrogels via simple chemical cross-linking of quaternized cellulose (QC) and native cellulose in NaOH/urea aqueous solution. The prepared hydrogel showed superabsorbent property, high mechanical strength, good biocompatibility, and excellent antimicrobial efficacy against Saccharomyces cerevisiae. The presence of QC in the hydrogel networks not only improved their swelling ratio via electrostatic repulsion of quaternary ammonium groups, but also endowed their antimicrobial activity by attraction of sections of anionic microbial membrane into internal pores of poly cationic hydrogel leading to the disruption of microbial membrane. Moreover, the swelling properties, mechanical strength, and antibacterial activity of hydrogels strongly depended on the contents of quaternary ammonium groups in hydrogel networks. The obtained data encouraged the use of these hydrogels for hygienic application such as disposable diapers.

  17. 浆粕性质对纤维素/[Bmim]Cl纺丝原液性能的影响%Effect of pulp characteristics on properties of cellulose/[ Bmim ] Cl spinning dope

    Institute of Scientific and Technical Information of China (English)

    张慧慧; 蔡涛; 周振兴; 邵惠丽; 胡学超

    2011-01-01

    Using three kinds of cotton and wood cellulose pulps as raw material and the ionic liquid of 1-butyl-3-methylimidazo-lium chloride ( [ Bmim]Cl) as solvent, the effect of the degree of polymerization (DP) and a -cellulose content of pulps on the cellulose dissolution in [Bmim]Cl, the rheological behavior of the spinning dope and the properties of the resulted fibers were discussed. The results showed that the higher the DP and α- cellulose content of cellulose pulp, the longer the dissolution time of cellulose in [ Bmim] Cl. The DP of pulp was the dominating factor on the dissolution rate of cellulose in [ Bmim] Cl as compared with α- cellulose content. Three kinds of cellulose/[ Bmim]Cl spinning dopes belonged to the typical shear thinning fluids. High DP and high α- cellulose content of the pulp contributed high structural viscosity index and viscous flow activation energy to the spinning dope. The pulp with high DP and high a- cellulose content helped to prepare the fiber with high mechanical properties.%选用棉浆和木浆3种纤维素浆粕为原料,以离子液体1-丁基-3-甲基咪唑氯盐([Bmim] Cl)为溶剂,探讨了浆粕的聚合度(DP)和α-纤维素含量对其在[Bmim] Cl中的溶解情况、纺丝液的流变行为及其纤维性能的影响.结果表明:浆粕的DP和α-纤维素含量越高,其在[Bmim] Cl中完全溶解所需时间就越长;相对于α-纤维素含量而言,DP对浆粕溶解速率的影响为主要因素;3种纤维素/[Bmim]Cl纺丝液都属于切力变稀流体,由高DP和高α-纤维素含量的浆粕所制得的纺丝液的结构粘度指数大且粘流活化能高;高DP和高α-纤维素含量的浆粕有利于获得力学性能更好的纤维素纤维.

  18. Efficient cellulose solvent: quaternary ammonium chlorides.

    Science.gov (United States)

    Kostag, Marc; Liebert, Tim; El Seoud, Omar A; Heinze, Thomas

    2013-10-01

    Pure quaternary tetraalkylammonium chlorides with one long alkyl chain dissolved in various organic solvents constitute a new class of cellulose solvents. The electrolytes are prepared in high yields and purity by Menshutkin quaternization, an inexpensive and easy synthesis route. The pure molten tetraalkylammonium chlorides dissolve up to 15 wt% of cellulose. Cosolvents, including N,N-dimethylacetamide (DMA), may be added in large excess, leading to a system of decreased viscosity. Contrary to the well-established solvent DMA/LiCl, cellulose dissolves in DMA/quaternary ammonium chlorides without any pretreatment. Thus, the use of the new solvent avoids some disadvantages of DMA/LiCl and ionic liquids, the most extensively employed solvents for homogeneous cellulose chemistry.

  19. Characterization of Bacterial Cellulose by Gluconacetobacter hansenii CGMCC 3917.

    Science.gov (United States)

    Feng, Xianchao; Ullah, Niamat; Wang, Xuejiao; Sun, Xuchun; Li, Chenyi; Bai, Yun; Chen, Lin; Li, Zhixi

    2015-10-01

    In this study, comprehensive characterization and drying methods on properties of bacterial cellulose were analyzed. Bacterial cellulose was prepared by Gluconacetobacter hansenii CGMCC 3917, which was mutated by high hydrostatic pressure (HHP) treatment. Bacterial cellulose is mainly comprised of cellulose Iα with high crystallinity and purity. High-water holding and absorption capacity were examined by reticulated structure. Thermogravimetric analysis showed high thermal stability. High tensile strength and Young's modulus indicated its mechanical properties. The rheological analysis showed that bacterial cellulose had good consistency and viscosity. These results indicated that bacterial cellulose is a potential food additive and also could be used for a food packaging material. The high textural stability during freeze-thaw cycles makes bacterial cellulose an effective additive for frozen food products. In addition, the properties of bacterial cellulose can be affected by drying methods. Our results suggest that the bacterial cellulose produced from HHP-mutant strain has an effective characterization, which can be used for a wide range of applications in food industry.

  20. Production and effect of aldonic acids during enzymatic hydrolysis of lignocellulose at high dry matter content

    OpenAIRE

    Cannella, David; Hsieh, Chia-wen; Felby, Claus; Jørgensen, Henning

    2012-01-01

    AbstractBackground: The recent discovery of accessory proteins that boost cellulose hydrolysis has increased theeconomical and technical efficiency of processing cellulose to bioethanol. Oxidative enzymes (e.g. GH61) present innew commercial enzyme preparations have shown to increase cellulose conversion yields. When using purecellulose substrates it has been determined that both oxidized and unoxidized cellodextrin products are formed. Wereport the effect of oxidative activity in a commercia...

  1. A multi-channel high time resolution detector for high content imaging

    CERN Document Server

    Lapington, J S; Miller, G M; Ashton, T J R; Jarron, P; Despeisse, M; Powolny, F; Howorth, J; Milnes, J

    2009-01-01

    Medical imaging has long benefited from advances in photon counting detectors arising from space and particle physics. We describe a microchannel plate-based detector system for high content (multi-parametric) analysis, specifically designed to provide a step change in performance and throughput for measurements in imaged live cells and tissue for the ‘omics’. The detector system integrates multi-channel, high time resolution, photon counting capability into a single miniaturized detector with integrated ASIC electronics, comprising a fast, low power amplifier discriminator and TDC for every channel of the discrete pixel electronic readout, and achieving a pixel density improvement of order two magnitudes compared with current comparable devices. The device combines high performance, easy reconfigurability, and economy within a compact footprint. We present simulations and preliminary measurements in the context of our ultimate goals of 20 ps time resolution with multi-channel parallel analysis (1024 chan...

  2. Engineering control of bacterial cellulose production using a genetic toolkit and a new cellulose-producing strain.

    Science.gov (United States)

    Florea, Michael; Hagemann, Henrik; Santosa, Gabriella; Abbott, James; Micklem, Chris N; Spencer-Milnes, Xenia; de Arroyo Garcia, Laura; Paschou, Despoina; Lazenbatt, Christopher; Kong, Deze; Chughtai, Haroon; Jensen, Kirsten; Freemont, Paul S; Kitney, Richard; Reeve, Benjamin; Ellis, Tom

    2016-06-14

    Bacterial cellulose is a strong and ultrapure form of cellulose produced naturally by several species of the Acetobacteraceae Its high strength, purity, and biocompatibility make it of great interest to materials science; however, precise control of its biosynthesis has remained a challenge for biotechnology. Here we isolate a strain of Komagataeibacter rhaeticus (K. rhaeticus iGEM) that can produce cellulose at high yields, grow in low-nitrogen conditions, and is highly resistant to toxic chemicals. We achieved external control over its bacterial cellulose production through development of a modular genetic toolkit that enables rational reprogramming of the cell. To further its use as an organism for biotechnology, we sequenced its genome and demonstrate genetic circuits that enable functionalization and patterning of heterologous gene expression within the cellulose matrix. This work lays the foundations for using genetic engineering to produce cellulose-based materials, with numerous applications in basic science, materials engineering, and biotechnology.

  3. Thermal Analysis of ZPPR High Pu Content Stored Fuel

    Directory of Open Access Journals (Sweden)

    Charles W. Solbrig

    2014-01-01

    Full Text Available The Zero Power Physics Reactor (ZPPR operated from April 18, 1969, until 1990. ZPPR operated at low power for testing nuclear reactor designs. This paper examines the temperature of Pu content ZPPR fuel while it is in storage. Heat is generated in the fuel due to Pu and Am decay and is a concern for possible cladding damage. Damage to the cladding could lead to fuel hydriding and oxidizing. A series of computer simulations were made to determine the range of temperatures potentially occuring in the ZPPR fuel. The maximum calculated fuel temperature is 292°C (558°F. Conservative assumptions in the model intentionally overestimate temperatures. The stored fuel temperatures are dependent on the distribution of fuel in the surrounding storage compartments, the heat generation rate of the fuel, and the orientation of fuel. Direct fuel temperatures could not be measured but storage bin doors, storage sleeve doors, and storage canister temperatures were measured. Comparison of these three temperatures to the calculations indicates that the temperatures calculated with conservative assumptions are, as expected, higher than the actual temperatures. The maximum calculated fuel temperature with the most conservative assumptions is significantly below the fuel failure criterion of 600°C (1,112°F.

  4. High dynamic range images for enhancing low dynamic range content

    OpenAIRE

    Banterle, Francesco; Dellepiane, Matteo; Scopigno, Roberto

    2011-01-01

    This poster presents a practical system for enhancing the quality of Low Dynamic Range (LDR) videos using High Dynamic Range (HDR) background images. Our technique relies on the assumption that the HDR information is static in the video footage. This assumption can be valid in many scenarios where moving subjects are the main focus of the footage and do not have to interact with moving light sources or highly reflective objects. Another valid scenario is teleconferencing via webcams, where th...

  5. Polyelectrolyte films based on chitosan/olive oil and reinforced with cellulose nanocrystals.

    Science.gov (United States)

    Pereda, Mariana; Dufresne, Alain; Aranguren, Mirta I; Marcovich, Norma E

    2014-01-30

    Composite films designed as potentially edible food packaging were prepared by casting film-forming emulsions based on chitosan/glycerol/olive oil containing dispersed cellulose nanocrystals (CNs). The combined use of cellulose nanoparticles and olive oil proved to be an efficient method to reduce the inherently high water vapor permeability of plasticized chitosan films, improving at the same time their tensile behavior. At the same time, it was found that the water solubility slightly decreased as the cellulose content increased, and further decreased with oil addition. Unexpectedly, opacity decreased as cellulose content increased, which balanced the reduced transparency due to lipid addition. Contact angle decreased with CN addition, but increased when olive oil was incorporated. Results from dynamic mechanical tests revealed that all films present two main relaxations that could be ascribed to the glycerol- and chitosan-rich phases, respectively. The response of plasticized chitosan-nanocellulose films (without lipid addition) was also investigated, in order to facilitate the understanding of the effect of both additives.

  6. Sono-assisted TEMPO oxidation of oil palm lignocellulosic biomass for isolation of nanocrystalline cellulose.

    Science.gov (United States)

    Rohaizu, R; Wanrosli, W D

    2017-01-01

    Highly stable and dispersible nanocrystalline cellulose (NCC) was successfully isolated from oil palm empty fruit bunch microcrystalline cellulose (OPEFB-MCC), with yields of 93% via a sono-assisted TEMPO-oxidation and a subsequent sonication process. The sono-assisted treatment has a remarkable effect, resulting in an increase of more than 100% in the carboxylate content and a significant increase of approximately 39% in yield compared with the non-assisted process. TEM images reveal the OPEFB-NCC to have rod-like crystalline morphology with an average length and width of 122 and 6nm, respectively. FTIR and solid-state (13)C-NMR analyses suggest that oxidation of cellulose chain hydroxyl groups occurs at C6. XRD analysis shows that OPEFB-NCC consists primarily of a crystalline cellulose I structure. Both XRD and (13)C-NMR indicate that the OPEFB-NCC has a lower crystallinity than the OPEFB-MCC starting material. Thermogravimetric analysis illustrates that OPEFB-NCC is less thermally stable than OPEFB-MCC but has a char content of 46% compared with 7% for the latter, which signifies that the carboxylate functionality acts as a flame retardant.

  7. Structural changes in microcrystalline cellulose in subcritical water treatment.

    Science.gov (United States)

    Tolonen, Lasse K; Zuckerstätter, Gerhard; Penttilä, Paavo A; Milacher, Walter; Habicht, Wilhelm; Serimaa, Ritva; Kruse, Andrea; Sixta, Herbert

    2011-07-11

    Subcritical water is a high potential green chemical for the hydrolysis of cellulose. In this study microcrystalline cellulose was treated in subcritical water to study structural changes of the cellulose residues. The alterations in particle size and appearance were studied by scanning electron microscopy (SEM) and those in the degree of polymerization (DP) and molar mass distributions by gel permeation chromatography (GPC). Further, changes in crystallinity and crystallite dimensions were quantified by wide-angle X-ray scattering and (13)C solid-state NMR. The results showed that the crystallinity remained practically unchanged throughout the treatment, whereas the size of the remaining cellulose crystallites increased. Microcrystalline cellulose underwent significant depolymerization in subcritical water. However, depolymerization leveled off at a relatively high degree of polymerization. The molar mass distributions of the residues showed a bimodal form. We infer that cellulose gets dissolved in subcritical water only after extensive depolymerization.

  8. Preparation and Characterization of Super Absorbent Resin from Natural Cellulose

    Institute of Scientific and Technical Information of China (English)

    李杰; 马凤国; 谭惠民

    2003-01-01

    The grafting polyacrylamide onto wood pulp cellulose (cell-g-PAM) was performed with cerous ammonium nitrate as the initiator and hydrolyzed to produce the super absorbent resin. The FTIR shows that the polyacrylamide is grafted on the cellulose. After hydrolyzation, part of acrylamino groups are transformed into carboxyl groups. The XRD analysis shows that the graft polymerization occurred at the amorphous section and the surface of the crystal section of cellulose. The SEM graph reveals that there is a layer of polymer on the surface of cellulose fiber and the fibril structure of the cellulose surface is covered. After hydrolyzation, the surface of the product is different from that of cell-g-PAM's and the surface is scraggy. The technical conditions to prepare high water absorbent resin were confirmed. Through the radical graft copolymerization, the high water absorbent resin can be produced from wood pulp cellulose.

  9. Poly(methyl vinyl ether-co-maleic acid)-polyethylene glycol nanocomposites cross-linked in situ with cellulose nanowhiskers.

    Science.gov (United States)

    Goetz, Lee; Foston, Marcus; Mathew, Aji P; Oksman, Kristiina; Ragauskas, Arthur J

    2010-10-11

    Nanocomposites were developed by cross-linking cellulose nanowhiskers with poly(methyl vinyl ether-co-maleic acid) and polyethylene glycol. Nuclear magnetic resonance (NMR) studies showed cross-linking occurs between the matrix and cellulose nanowhiskers via an esterification reaction. Proton NMR T(2) relaxation experiments provided information on the mobility of the polymer chains within the matrix, which can be related to the structure of the cross-linked nanocomposite. The nanocomposite was found to consist of mobile chain portions between cross-linked junction points and immobilized chain segments near or at those junction points, whose relative fraction increased upon further incorporation of cellulose nanowhiskers. Atomic force microscopy images showed a homogeneous dispersion of nanowhiskers in the matrix even at high nanowhisker content, which can be attributed to cross-linking of the nanowhiskers in the matrix. Relative humidity conditions were found to affect the mechanical properties of the composites negatively while the nanowhiskers content had a positive effect. It is expected that the cross-links between the matrix and the cellulose nanowhiskers trap the nanowhiskers in the cross-linked network, preventing nanowhisker aggregation subsequently producing cellulose nanocomposites with unique mechanical behaviors. The results show that in situ cross-linking of cellulose nanowhiskers with a matrix polymer is a promising route to obtain nanocomposites with well dispersed nanowhiskers, tailored nanostructure, and mechanical performance.

  10. Reconstitution of cellulose and lignin after [C2mim][OAc] pretreatment and its relation to enzymatic hydrolysis.

    Science.gov (United States)

    Yuan, Tong-Qi; Wang, Wei; Zhang, Li-Ming; Xu, Feng; Sun, Run-Cang

    2013-03-01

    Although the effects of cellulose crystallinity and lignin content as two major structural features on enzymatic hydrolysis have been extensively studied, debates regarding their effects still exist. In this study, reconstitution of cellulose and lignin after 1-ethyl-3-methylimidazolium acetate ([C(2)mim][OAc]) pretreatment was proposed as a new method to study their effects on enzymatic digestibility. Different mechanisms of lignin content for reduction of cellulose hydrolysis were found between the proposed method and the traditional method (mixing of cellulose and lignin). The results indicated that a slight change of the crystallinity of the reconstituted materials may play a minor role in the change of enzyme efficiency. In addition, the present study suggested that the lignin content does not significantly affect the digestibility of cellulose, whereas the conversion of cellulose fibers from the cellulose I to the cellulose II crystal phase plays an important role when an ionic liquid pretreatment of biomass was conducted. Copyright © 2012 Wiley Periodicals, Inc.

  11. Cellulose gel dispersion: From pure hydrogel suspensions to encapsulated oil-in-water emulsions.

    Science.gov (United States)

    Napso, Sofia; Rein, Dmitry M; Khalfin, Rafail; Kleinerman, Olga; Cohen, Yachin

    2016-01-01

    Cellulose hydrogel particles were fabricated from molecularly-dissolved cellulose/IL solutions. The characteristics of the formed hydrogels (cellulose content, particles' size and porosity) were determined as a function of cellulose concentration in the precursor solutions. There is a significant change in the hydrogel structure when the initial cellulose solution concentration increases above about 7-9%wt. These changes include increase of the cellulose content in the hydrogel, and decrease in its pore size. The finest cellulose particle dispersions can be obtained using low concentration cellulose/IL solutions (cellulose concentration in dispersion less than 2%wt.) or hydrogels (concentration less than 1%wt.) in a dispersing medium consisting of IL with no more than 20%wt. water. Stable paraffin oil-in-water emulsions are achieved by mixing oil and water with cellulose/IL solutions. The optimal conditions for obtaining the finest particles (about 20μm in diameter) are attained using cellulose solutions of concentration between 0.7 and 4%wt. at temperature of 70°C and oil/cellulose mass ratios between 1 and 1.5.

  12. Cellulose fiber reinforced nylon 6 or nylon 66 composites

    Science.gov (United States)

    Xu, Xiaolin

    Cellulose fiber was used to reinforce higher melting temperature engineering thermoplastics, such as nylon 6 and nylon 66. The continuous extrusion - direct compression molding processing and extrusion-injection molding were chosen to make cellulose fiber/nylon 6 or 66 composites. Tensile, flexural and Izod impact tests were used to demonstrate the mechanical properties of the composites. The continuous extrusion-compression molding processing can decrease the thermal degradation of cellulose fiber, but fiber doesn't disperse well with this procedure. Injection molding gave samples with better fiber dispersion and less void content, and thus gave better mechanical properties than compression molding. Low temperature compounding was used to extrude cellulose fiber/nylon composites. Plasticizer and a ceramic powder were used to decrease the processing temperature. Low temperature extrusion gave better mechanical properties than high temperature extrusion. The tensile modulus of nylon 6 composite with 30% fiber can reach 5GPa; with a tensile strength of 68MPa; a flexural modulus of 4GPa, and a flexural strength of 100MPa. The tensile modulus of nylon 66 composites with 30% fiber can reach 5GPa; with a flexural modulus of 5GPa; a tensile strength of 70MPa; and a flexural strength of 147MPa. The effect of thermal degradation on fiber properties was estimated. The Halpin-Tsai model and the Cox model were used to estimate the composite modulus. The Kelly-Tyson model was used to estimate the composite strength. The result indicates that the change of fiber properties determines the final properties of composites. Fiber length has a minor affect on both modulus and strength as long as the fiber length is above the critical length.

  13. Bacterial-cellulose-derived interconnected meso-microporous carbon nanofiber networks as binder-free electrodes for high-performance supercapacitors

    Science.gov (United States)

    Hao, Xiaodong; Wang, Jie; Ding, Bing; Wang, Ya; Chang, Zhi; Dou, Hui; Zhang, Xiaogang

    2017-06-01

    Bacterial cellulose (BC), a typical biomass prepared from the microbial fermentation process, has been proved that it can be an ideal platform for design of three-dimensional (3D) multifunctional nanomaterials in energy storage and conversion field. Here we developed a simple and general silica-assisted strategy for fabrication of interconnected 3D meso-microporous carbon nanofiber networks by confine nanospace pyrolysis of sustainable BC, which can be used as binder-free electrodes for high-performance supercapacitors. The synthesized carbon nanofibers exhibited the features of interconnected 3D networks architecture, large surface area (624 m2 g-1), mesopores-dominated hierarchical porosity, and high graphitization degree. The as-prepared electrode (CN-BC) displayed a maximum specific capacitance of 302 F g-1 at a current density of 0.5 A g-1, high-rate capability and good cyclicity in 6 M KOH electrolyte. This work, together with cost-effective preparation strategy to make high-value utilization of cheap biomass, should have significant implications in the green and mass-producible energy storage.

  14. Copper removal using electrosterically stabilized nanocrystalline cellulose.

    Science.gov (United States)

    Sheikhi, Amir; Safari, Salman; Yang, Han; van de Ven, Theo G M

    2015-06-03

    Removal of heavy metal ions such as copper using an efficient and low-cost method with low ecological footprint is a critical process in wastewater treatment, which can be achieved in a liquid phase using nanoadsorbents such as inorganic nanoparticles. Recently, attention has turned toward developing sustainable and environmentally friendly nanoadsorbents to remove heavy metal ions from aqueous media. Electrosterically stabilized nanocrystalline cellulose (ENCC), which can be prepared from wood fibers through periodate/chlorite oxidation, has been shown to have a high charge content and colloidal stability. Here, we show that ENCC scavenges copper ions by different mechanisms depending on the ion concentration. When the Cu(II) concentration is low (C0≲200 ppm), agglomerates of starlike ENCC particles appear, which are broken into individual starlike entities by shear and Brownian motion, as evidenced by photometric dispersion analysis, dynamic light scattering, and transmission electron microscopy. On the other hand, at higher copper concentrations, the aggregate morphology changes from starlike to raftlike, which is probably due to the collapse of protruding dicarboxylic cellulose (DCC) chains and ENCC charge neutralization by copper adsorption. Such raftlike structures result from head-to-head and lateral aggregation of neutralized ENCCs as confirmed by transmission electron microscopy. As opposed to starlike aggregates, the raftlike structures grow gradually and are prone to sedimentation at copper concentrations C0≳500 ppm, which eliminates a costly separation step in wastewater treatment processes. Moreover, a copper removal capacity of ∼185 mg g(-1) was achieved thanks to the highly charged DCC polyanions protruding from ENCC. These properties along with the biorenewability make ENCC a promising candidate for wastewater treatment, in which fast, facile, and low-cost removal of heavy metal ions is desired most.

  15. Fulton Cellulosic Ethanol Biorefinery

    Energy Technology Data Exchange (ETDEWEB)

    Sumait, Necy [BlueFire Ethanol, Irvine, CA (United States); Cuzens, John [BlueFire Ethanol, Irvine, CA (United States); Klann, Richard [BlueFire Ethanol, Irvine, CA (United States)

    2015-07-24

    Final report on work performed by BlueFire on the deployment of acid hydrolysis technology to convert cellulosic waste materials into renewable fuels, power and chemicals in a production facility to be located in Fulton, Mississippi.

  16. Teores de lignina e celulose em plantas de cana-de-açúcar em função da aplicação de maturadores Lignin and cellulose contents in sugarcane after ripener application

    Directory of Open Access Journals (Sweden)

    D.K. Meschede

    2012-03-01

    Full Text Available O objetivo deste trabalho foi avaliar os teores de lignina e celulose em plantas de cana-de-açúcar após a aplicação de dois maturadores para a colheita. O experimento foi conduzido em uma área de cana-soca, cultivar SP 803280, no município de Igaraçu do Tietê/SP. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições. Os tratamentos constituíram-se da aplicação de dois maturadores: sulfometuron-methyl (Curavial e glyphosate (Roundup original. As doses utilizadas foram: glyphosate a 72 g e.a. ha-1; glyphosate a 144 g e.a. ha-1 ; glyphosate a 72 g e.a. ha-1 + sulfometuron methyl a 10 g p.c. ha-1; glyphosate a 108 g e.a. ha-1 + sulfometuron-methyl a 12 g p.c. ha-1; sulfometuron-methyl a 20 g p.c. ha-1; e a testemunha sem aplicação de maturadores. As análises de lignina e celulose foram realizadas pelo método lignina em detergente ácido modificado. O glyphosate e o sulfometuron-methyl alteraram os níveis de lignina no momento da colheita, e esse efeito foi observado também durante o crescimento da cana-de-açúcar (meses após a aplicação desses produtos. O glyphosate a 72 g e.a. ha-1 promoveu reduções nos teores de lignina, na colheita e durante o crescimento da cana-de-açúcar, quando comparados com os da testemunha, enquanto o sulfometuron-methyl isolado na menor dose (10 g ha-1 promoveu aumento nos teores desse biopolímero na soqueira da cana-de-açúcar.The aim of this study was to evaluate the content of lignin and cellulose in sugarcane after application of ripeners. The experiment was carried out in a sugarcane ratoon area, variety SP803280 in Igaraçu Tietê, São Paulo, Brazil. The experimental design was a randomized complete block with four replications. The treatments consisted of application of two ripeners: sulfometuron methyl (Curavial and glyphosate (Roundup Original. The doses used were: glyphosate 200 mL pc ha-1; glyphosate at 400 mL p.c. ha-1, glyphosate at 200 mL p

  17. Experimental study on cellulose particulate and its composites

    Science.gov (United States)

    Srinivasababu, Nadendla

    2016-05-01

    Anselme Payen has discovered cellulose after conducting rigorous experiments on wood. In this work an attempt is made to reinforce cellulose particulate into polyester matrix from 1.84 - 9.18 wt % and the lamina is manufactured by JMFIL technique. The fabricated lamina is cut into specimens for various tests as per ASTM standards. Tensile strength of 22.61 MPa is achieved at 1.84 % of cellulose content in composites. Then the cellulose composites at 1.89% of reinforcement level showed 55.57 MPa, 1.86 GPa flexural strength, modulus respectively. `C' kind of failure is visualized for all the specimens and volume fractions during impact test. The cellulose particulate is also analyzed for its morphology, size.

  18. A parallel microfluidic flow cytometer for high-content screening.

    Science.gov (United States)

    McKenna, Brian K; Evans, James G; Cheung, Man Ching; Ehrlich, Daniel J

    2011-05-01

    A parallel microfluidic cytometer (PMC) uses a high-speed scanning photomultiplier-based detector to combine low-pixel-count, one-dimensional imaging with flow cytometry. The 384 parallel flow channels of the PMC decouple count rate from signal-to-noise ratio. Using six-pixel one-dimensional images, we investigated protein localization in a yeast model for human protein misfolding diseases and demonstrated the feasibility of a nuclear-translocation assay in Chinese hamster ovary (CHO) cells expressing an NFκB-EGFP reporter.

  19. Sensing the structural differences in cellulose from apple and bacterial cell wall materials by Raman and FT-IR spectroscopy.

    Science.gov (United States)

    Szymańska-Chargot, Monika; Cybulska, Justyna; Zdunek, Artur

    2011-01-01

    Raman and Fourier Transform Infrared (FT-IR) spectroscopy was used for assessment of structural differences of celluloses of various origins. Investigated celluloses were: bacterial celluloses cultured in presence of pectin and/or xyloglucan, as well as commercial celluloses and cellulose extracted from apple parenchyma. FT-IR spectra were used to estimate of the I(β) content, whereas Raman spectra were used to evaluate the degree of crystallinity of the cellulose. The crystallinity index (X(C)(RAMAN)%) varied from -25% for apple cellulose to 53% for microcrystalline commercial cellulose. Considering bacterial cellulose, addition of xyloglucan has an impact on the percentage content of cellulose I(β). However, addition of only xyloglucan or only pectins to pure bacterial cellulose both resulted in a slight decrease of crystallinity. However, culturing bacterial cellulose in the presence of mixtures of xyloglucan and pectins results in an increase of crystallinity. The results confirmed that the higher degree of crystallinity, the broader the peak around 913 cm(-1). Among all bacterial celluloses the bacterial cellulose cultured in presence of xyloglucan and pectin (BCPX) has the most similar structure to those observed in natural primary cell walls.

  20. Sensing the Structural Differences in Cellulose from Apple and Bacterial Cell Wall Materials by Raman and FT-IR Spectroscopy

    Directory of Open Access Journals (Sweden)

    Artur Zdunek

    2011-05-01

    Full Text Available Raman and Fourier Transform Infrared (FT-IR spectroscopy was used for assessment of structural differences of celluloses of various origins. Investigated celluloses were: bacterial celluloses cultured in presence of pectin and/or xyloglucan, as well as commercial celluloses and cellulose extracted from apple parenchyma. FT-IR spectra were used to estimate of the Iβ content, whereas Raman spectra were used to evaluate the degree of crystallinity of the cellulose. The crystallinity index (XCRAMAN% varied from −25% for apple cellulose to 53% for microcrystalline commercial cellulose. Considering bacterial cellulose, addition of xyloglucan has an impact on the percentage content of cellulose Iβ. However, addition of only xyloglucan or only pectins to pure bacterial cellulose both resulted in a slight decrease of crystallinity. However, culturing bacterial cellulose in the presence of mixtures of xyloglucan and pectins results in an increase of crystallinity. The results confirmed that the higher degree of crystallinity, the broader the peak around 913 cm−1. Among all bacterial celluloses the bacterial cellulose cultured in presence of xyloglucan and pectin (BCPX has the most similar structure to those observed in natural primary cell walls.

  1. Effect of Surface Attachment on Synthesis of Bacterial Cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Barbara R [ORNL; O' Neill, Hugh Michael [ORNL

    2005-01-01

    Gluconacetobacter spp. synthesize a pure form of hydrophilic cellulose that has several industrial specialty applications. Literature reports have concentrated on intensive investigation of static and agitated culture in liquid media containing high nutrient concentrations optimized for maximal cellulose production rates. The behavior of these bacteria on semisolid and solid surfaces has not been specifically addressed. The species Gluconacetobacter hansenii was examined for cellulose synthesis and colony morphology on a range of solid supports, including cotton linters, and on media thickened with agar, methyl cellulose, or gellan. The concentration and chemical structure of the thickening agent were found to be directly related to the formation of contiguous cellulose pellicules. Viability of the bacteria following freezer storage was improved when the bacteria were frozen in their cellulose pellicules.

  2. Traffic jams reduce hydrolytic efficiency of cellulase on cellulose surface.

    Science.gov (United States)

    Igarashi, Kiyohiko; Uchihashi, Takayuki; Koivula, Anu; Wada, Masahisa; Kimura, Satoshi; Okamoto, Tetsuaki; Penttilä, Merja; Ando, Toshio; Samejima, Masahiro

    2011-09-02

    A deeper mechanistic understanding of the saccharification of cellulosic biomass could enhance the efficiency of biofuels development. We report here the real-time visualization of crystalline cellulose degradation by individual cellulase enzymes through use of an advanced version of high-speed atomic force microscopy. Trichoderma reesei cellobiohydrolase I (TrCel7A) molecules were observed to slide unidirectionally along the crystalline cellulose surface but at one point exhibited collective halting analogous to a traffic jam. Changing the crystalline polymorphic form of cellulose by means of an ammonia treatment increased the apparent number of accessible lanes on the crystalline surface and consequently the number of moving cellulase molecules. Treatment of this bulky crystalline cellulose simultaneously or separately with T. reesei cellobiohydrolase II (TrCel6A) resulted in a remarkable increase in the proportion of mobile enzyme molecules on the surface. Cellulose was completely degraded by the synergistic action between the two enzymes.

  3. Cellulose-Based Bio- and Nanocomposites: A Review

    Directory of Open Access Journals (Sweden)

    Susheel Kalia

    2011-01-01

    Full Text Available Cellulose macro- and nanofibers have gained increasing attention due to the high strength and stiffness, biodegradability and renewability, and their production and application in development of composites. Application of cellulose nanofibers for the development of composites is a relatively new research area. Cellulose macro- and nanofibers can be used as reinforcement in composite materials because of enhanced mechanical, thermal, and biodegradation properties of composites. Cellulose fibers are hydrophilic in nature, so it becomes necessary to increase their surface roughness for the development of composites with enhanced properties. In the present paper, we have reviewed the surface modification of cellulose fibers by various methods. Processing methods, properties, and various applications of nanocellulose and cellulosic composites are also discussed in this paper.

  4. Synthesis of Highly Polymerized Water-soluble Cellulose Acetate by the Side Reaction in Carboxylate Ionic Liquid 1-ethyl-3-methylimidazolium Acetate

    Science.gov (United States)

    Pang, Jinhui; Liu, Xin; Yang, Jun; Lu, Fachuang; Wang, Bo; Xu, Feng; Ma, Mingguo; Zhang, Xueming

    2016-09-01

    In the present study, we describe a novel one-step method to prepare water-soluble cellulose acetate (WSCA) with higher degree of polymerization values (DP = 650–680) by in situ activation of carboxyl group in ionic liquid. First of all, cellulose was dissolved in 1-ethyl-3-methylimidazolium acetate (EmimAc) and reacted with dichloroacetyl chloride (Cl2AcCl) in order to make cellulose dichloroacetate. Under various conditions, a series of water soluble products were produced. Elemental analysis and NMR results confirmed that they were cellulose acetate with DS (degree of substitution) values in the range from 0.30 to 0.63. NMR studies demonstrated that Cl2AcCl reacted with acetate anion of EmimAc producing a mixed anhydride that acetylated cellulose. Other acylating reagents such as benzoyl chloride, chloroacetyl chloride can also work similarly. 2D NMR characterization suggested that 6-mono-O-acetyl moiety, 3,6-di-O-acetylcellulose and 2,6-di-O-acetyl cellulose were all synthesized and the reactivity of hydroxyl groups in anhydro-glucose units was in the order C-6>C-3>C-2. This work provides an alternative way to make WSCA, meanwhile, also services as a reminder that the activity of EmimAc toward carbohydrate as acylating reagents could be a problem, because the expected acylated products may not be resulted and recycling of this ionic liquid could also be difficult.

  5. Synthesis of Highly Polymerized Water-soluble Cellulose Acetate by the Side Reaction in Carboxylate Ionic Liquid 1-ethyl-3-methylimidazolium Acetate

    Science.gov (United States)

    Pang, Jinhui; Liu, Xin; Yang, Jun; Lu, Fachuang; Wang, Bo; Xu, Feng; Ma, Mingguo; Zhang, Xueming

    2016-01-01

    In the present study, we describe a novel one-step method to prepare water-soluble cellulose acetate (WSCA) with higher degree of polymerization values (DP = 650–680) by in situ activation of carboxyl group in ionic liquid. First of all, cellulose was dissolved in 1-ethyl-3-methylimidazolium acetate (EmimAc) and reacted with dichloroacetyl chloride (Cl2AcCl) in order to make cellulose dichloroacetate. Under various conditions, a series of water soluble products were produced. Elemental analysis and NMR results confirmed that they were cellulose acetate with DS (degree of substitution) values in the range from 0.30 to 0.63. NMR studies demonstrated that Cl2AcCl reacted with acetate anion of EmimAc producing a mixed anhydride that acetylated cellulose. Other acylating reagents such as benzoyl chloride, chloroacetyl chloride can also work similarly. 2D NMR characterization suggested that 6-mono-O-acetyl moiety, 3,6-di-O-acetylcellulose and 2,6-di-O-acetyl cellulose were all synthesized and the reactivity of hydroxyl groups in anhydro-glucose units was in the order C-6>C-3>C-2. This work provides an alternative way to make WSCA, meanwhile, also services as a reminder that the activity of EmimAc toward carbohydrate as acylating reagents could be a problem, because the expected acylated products may not be resulted and recycling of this ionic liquid could also be difficult. PMID:27644545

  6. Methods of pretreating comminuted cellulosic material with carbonate-containing solutions

    Science.gov (United States)

    Francis, Raymond

    2012-11-06

    Methods of pretreating comminuted cellulosic material with an acidic solution and then a carbonate-containing solution to produce a pretreated cellulosic material are provided. The pretreated material may then be further treated in a pulping process, for example, a soda-anthraquinone pulping process, to produce a cellulose pulp. The pretreatment solutions may be extracted from the pretreated cellulose material and selectively re-used, for example, with acid or alkali addition, for the pretreatment solutions. The resulting cellulose pulp is characterized by having reduced lignin content and increased yield compared to prior art treatment processes.

  7. High content image cytometry in the context of subnuclear organization.

    Science.gov (United States)

    De Vos, W H; Van Neste, L; Dieriks, B; Joss, G H; Van Oostveldt, P

    2010-01-01

    The organization of proteins in space and time is essential to their function. To accurately quantify subcellular protein characteristics in a population of cells with regard for the stochasticity of events in a natural context, there is a fast-growing need for image-based cytometry. Simultaneously, the massive amount of data that is generated by image-cytometric analyses, calls for tools that enable pattern recognition and automated classification. In this article, we present a general approach for multivariate phenotypic profiling of individual cell nuclei and quantification of subnuclear spots using automated fluorescence mosaic microscopy, optimized image processing tools, and supervised classification. We demonstrate the efficiency of our analysis by determination of differential DNA damage repair patterns in response to genotoxic stress and radiation, and we show the potential of data mining in pinpointing specific phenotypes after transient transfection. The presented approach allowed for systematic analysis of subnuclear features in large image data sets and accurate classification of phenotypes at the level of the single cell. Consequently, this type of nuclear fingerprinting shows potential for high-throughput applications, such as functional protein assays or drug compound screening.

  8. Bacterial cellulose-kaolin nanocomposites for application as biomedical wound healing materials

    Science.gov (United States)

    Wanna, Dwi; Alam, Catharina; Toivola, Diana M.; Alam, Parvez

    2013-12-01

    This short communication provides preliminary experimental details on the structure-property relationships of novel biomedical kaolin-bacterial cellulose nanocomposites. Bacterial cellulose is an effective binding agent for kaolin particles forming reticulated structures at kaolin-cellulose interfaces and entanglements when the cellulose fraction is sufficiently high. The mechanical performance of these materials hence improves with an increased fraction of bacterial cellulose, though this also causes the rate of blood clotting to decrease. These composites have combined potential as both short-term (kaolin) and long-term (bacterial cellulose) wound healing materials.

  9. Decreased adipose tissue zinc content is associated with metabolic parameters in high fat fed Wistar rats

    OpenAIRE

    Alexey A. Tinkov; Elizaveta V. Popova; Evgenia R. Gatiatulina; Anastasia A. Skalnaya; Elena N. Yakovenko; Irina B. Alchinova; Mikhail Y. Karganov; Anatoly V. Skalny; Nikonorov, Alexandr A.

    2016-01-01

    Background. Limited data on adipose tissue zinc content in obesity exist. At the same time, the association between adipose tissue zinc content and metabolic parameters in dietary-induced obesity is poorly studied. Therefore, the primary objective of this study is to assess adipose tissue zinc content and its association  with morphometric parameters, adipokine spectrum, proinflammatory cytokines, and apolipoprotein profile in high fat fed Wistar rats. Material and method...

  10. Trend in Plutonium Content of MOX in Thermal Reactor Use and Irradiation Behavior of MOX with High Plutonium Content

    Energy Technology Data Exchange (ETDEWEB)

    Nakae, N.; Baba, T.; Kamimura, K. [Japan Nuclear Energy Safety Organization - JNES, TOKYU REIT Toranomon Bldg., 3-17-1, Toranomon, Minato-ku, Tokyo, 105-0001 (Japan); Verwerft, M.; Jutier, F. [SCK-CEN (Belgium)

    2009-06-15

    The uranium enrichment of UO{sub 2} fuel for the current power reactors, both PWR and BWR, tends to increase because of increasing burn-up target. The plutonium content of MOX fuel used in thermal reactors shall be determined in order to have reactivity worth equivalent to enriched UO{sub 2} fuel based on physical accounting method for adjusting fissile enrichment, thus the plutonium content tends to increase according to the increment of the uranium enrichment of UO{sub 2} fuel and this trend shall further be accentuated due to the fact that Pu recovered from reprocessing of the spent high burnup UO{sub 2} fuel contains less fissile isotopes. The plutonium content is calculated by use of the physical accounting method with the plutonium having several kinds of isotope ratios and the calculation results indicate that the plutonium content in MOX will evolve to ratios in excess of 10%. It shall be, therefore, important to know the irradiation behavior of MOX with high plutonium content of more than 10 wt%. MOX fuel rods having a plutonium content of about 14 wt% and fabricated by use of MIMAS process have been irradiated under PWR conditions in the Belgian test reactors BR-3 and BR-2. The peak fuel rod burn-up of the fuel rods studied in this paper ranges from 31 to 37 GWd/t-HM, and their average burnup is about 22-26 GWd/t-HM with the rod averaged linear heat generation rate of about 15-21 kW/m. The MOX rods are investigated by destructive and non-destructive post irradiation examinations and some of them are now continued to be irradiated in BR-2. Mixed Oxide (U,Pu)O{sub 2} fuel produced by the MIMAS process results in a fine dispersion of Pu enriched particles in a UO{sub 2} matrix and effectively gives three enrichment classes: low, medium and high enriched. The high enriched particles (often called 'Pu spots'), have an enrichment of around 25 wt% Pu, the low enriched phase is the UO{sub 2} matrix and contains only trace amounts of Pu. An

  11. Cellulose: A review as natural, modified and activated carbon adsorbent.

    Science.gov (United States)

    Suhas; Gupta, V K; Carrott, P J M; Singh, Randhir; Chaudhary, Monika; Kushwaha, Sarita

    2016-09-01

    Cellulose is a biodegradable, renewable, non-meltable polymer which is insoluble in most solvents due to hydrogen bonding and crystallinity. Natural cellulose shows lower adsorption capacity as compared to modified cellulose and its capacity can be enhanced by modification usually by chemicals. This review focuses on the utilization of cellulose as an adsorbent in natural/modified form or as a precursor for activated carbon (AC) for adsorbing substances from water. The literature revealed that cellulose can be a promising precursor for production of activated carbon with appreciable surface area (∼1300m(2)g(-1)) and total pore volume (∼0.6cm(3)g(-1)) and the surface area and pore volume varies with the cellulose content. Finally, the purpose of review is to report a few controversies and unresolved questions concerning the preparation/properties of ACs from cellulose and to make aware to readers that there is still considerable scope for future development, characterization and utilization of ACs from cellulose.

  12. Methods for the Selective Oxidation of Cellulose: Preparation of 2,3-Dicarboxycellulose and 6-Carboxycellulose

    NARCIS (Netherlands)

    Besemer, A.C.; Nooy, A.E.J. de; Bekkum, H. van

    1998-01-01

    Three methods for the selective oxidation of cellulose are described. The classical method consists of consecutive oxidation with sodium periodate, leading to 2,3-dialdehyde cellulose and sodium chlorite, giving 2,3-dicarboxy cellulose. This material, which is obtained in high yield and has a high

  13. Methods for the Selective Oxidation of Cellulose: Preparation of 2,3-Dicarboxycellulose and 6-Carboxycellulose

    NARCIS (Netherlands)

    Besemer, A.C.; Nooy, A.E.J. de; Bekkum, H. van

    1998-01-01

    Three methods for the selective oxidation of cellulose are described. The classical method consists of consecutive oxidation with sodium periodate, leading to 2,3-dialdehyde cellulose and sodium chlorite, giving 2,3-dicarboxy cellulose. This material, which is obtained in high yield and has a high c

  14. Grafting of carboxybetaine brush onto cellulose membranes via surface-initiated ARGET-ATRP for improving blood compatibility.

    Science.gov (United States)

    Wang, Miao; Yuan, Jiang; Huang, Xiaobo; Cai, Xianmei; Li, Li; Shen, Jian

    2013-03-01

    Grafting-from has proven to be a very effective way to create high grafting densities and well-controlled polymer chains on different kinds of surfaces. In this work, we aim to graft zwitterionic brush from cellulose membrane (CM) via ARGET-ATRP (Activator Regenerated by Electron Transfer ATRP) method indirectly for blood compatibility improvement. Characterization of the CM substrates before and after modification was carried out by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), water contact angle measurements, X-ray photoelectron spectroscopy analysis, and atomic force microscopy, respectively. The results demonstrated zwitterionic brushes were successfully grafted on the CM surfaces, and the content of the grafted layer increased gradually with the polymerization time. The platelet adhesion, hemolytic test and plasma protein adsorption results indicated the cellulose membrane had significantly excellent blood compatibility featured on lower platelet adhesion and protein adsorption without causing hemolysis. The functionalized cellulose substrate could have a great potential usage for biomedical applications.

  15. Synthesis and Characterization of Mesoporous Silicon Oxynitride MCM-41 with High Nitrogen Content

    Institute of Scientific and Technical Information of China (English)

    ZHANG Cunman; XU Zheng; LIU Qian

    2005-01-01

    Mesoporous silicon oxynitrides MCM-41 were synthesized successfully. The resulting materials not only have high nitrogen contents and good structural characteristics of MCM-41 (high surface area, narrow pore size distribution and good order), but also are amorphous. The composition and structure of the materials were investigated by CNH element analysis, XPS, Si MAS NMR, XRD, HRTEM and N2 sorption, respectively. Mesoporous silicon oxynitrides MCM-41 with a high nitrogen content are still non-crystal (amorphous).

  16. Method of preparing a high solids content, low viscosity ceramic slurry

    Science.gov (United States)

    Tiegs, Terry N.; Wittmer, Dale E.

    1995-01-01

    A method for producing a high solids content, low viscosity ceramic slurry composition comprises turbomilling a dispersion of a ceramic powder in a liquid to form a slurry having a viscosity less than 100 centipoise and a solids content equal to or greater than 48 volume percent.

  17. Content-Based Curriculum for High-Ability Learners, Second Edition

    Science.gov (United States)

    VanTassel-Baska, Joyce, Ed.; Little, Catherine A., Ed.

    2011-01-01

    The newly updated "Content-Based Curriculum for High-Ability Learners" provides a solid introduction to curriculum development in gifted and talented education. Written by experts in the field of gifted education, this text uses cutting-edge design techniques and aligns the core content with national and state standards. In addition to a revision…

  18. Transcriptional Regulation and Adaptation to a High-Fiber Environment in Bacillus subtilis HH2 Isolated from Feces of the Giant Panda: e0116935

    National Research Council Canada - National Science Library

    Ziyao Zhou; Xiaoxiao Zhou; Jin Li; Zhijun Zhong; Wei Li; Xuehan Liu; Furui Liu; Huaiyi Su; Yongjiu Luo; Wuyang Gu; Chengdong Wang; Hemin Zhang; Desheng Li; Tingmei He; Hualin Fu; Suizhong Cao; Jinjiang Shi; Guangneng Peng

    2015-01-01

      In the giant panda, adaptation to a high-fiber environment is a first step for the adequate functioning of intestinal bacteria, as the high cellulose content of the gut due to the panda's vegetarian...

  19. Transcriptional regulation and adaptation to a high-fiber environment in Bacillus subtilis HH2 isolated from feces of the giant panda

    National Research Council Canada - National Science Library

    Zhou, Ziyao; Zhou, Xiaoxiao; Li, Jin; Zhong, Zhijun; Li, Wei; Liu, Xuehan; Liu, Furui; Su, Huaiyi; Luo, Yongjiu; Gu, Wuyang; Wang, Chengdong; Zhang, Hemin; Li, Desheng; He, Tingmei; Fu, Hualin; Cao, Suizhong; Shi, Jinjiang; Peng, Guangneng

    2015-01-01

    In the giant panda, adaptation to a high-fiber environment is a first step for the adequate functioning of intestinal bacteria, as the high cellulose content of the gut due to the panda's vegetarian...

  20. Flexible Lamination-Fabricated Ultra-High Frequency Diodes Based on Self-Supporting Semiconducting Composite Film of Silicon Micro-Particles and Nano-Fibrillated Cellulose

    Science.gov (United States)

    Sani, Negar; Wang, Xin; Granberg, Hjalmar; Andersson Ersman, Peter; Crispin, Xavier; Dyreklev, Peter; Engquist, Isak; Gustafsson, Göran; Berggren, Magnus

    2016-06-01

    Low cost and flexible devices such as wearable electronics, e-labels and distributed sensors will make the future “internet of things” viable. To power and communicate with such systems, high frequency rectifiers are crucial components. We present a simple method to manufacture flexible diodes, operating at GHz frequencies, based on self-adhesive composite films of silicon micro-particles (Si-μPs) and glycerol dispersed in nanofibrillated cellulose (NFC). NFC, Si-μPs and glycerol are mixed in a water suspension, forming a self-supporting nanocellulose-silicon composite film after drying. This film is cut and laminated between a flexible pre-patterned Al bottom electrode and a conductive Ni-coated carbon tape top contact. A Schottky junction is established between the Al electrode and the Si-μPs. The resulting flexible diodes show current levels on the order of mA for an area of 2 mm2, a current rectification ratio up to 4 × 103 between 1 and 2 V bias and a cut-off frequency of 1.8 GHz. Energy harvesting experiments have been demonstrated using resistors as the load at 900 MHz and 1.8 GHz. The diode stack can be delaminated away from the Al electrode and then later on be transferred and reconfigured to another substrate. This provides us with reconfigurable GHz-operating diode circuits.

  1. Flexible Lamination-Fabricated Ultra-High Frequency Diodes Based on Self-Supporting Semiconducting Composite Film of Silicon Micro-Particles and Nano-Fibrillated Cellulose.

    Science.gov (United States)

    Sani, Negar; Wang, Xin; Granberg, Hjalmar; Andersson Ersman, Peter; Crispin, Xavier; Dyreklev, Peter; Engquist, Isak; Gustafsson, Göran; Berggren, Magnus

    2016-01-01

    Low cost and flexible devices such as wearable electronics, e-labels and distributed sensors will make the future "internet of things" viable. To power and communicate with such systems, high frequency rectifiers are crucial components. We present a simple method to manufacture flexible diodes, operating at GHz frequencies, based on self-adhesive composite films of silicon micro-particles (Si-μPs) and glycerol dispersed in nanofibrillated cellulose (NFC). NFC, Si-μPs and glycerol are mixed in a water suspension, forming a self-supporting nanocellulose-silicon composite film after drying. This film is cut and laminated between a flexible pre-patterned Al bottom electrode and a conductive Ni-coated carbon tape top contact. A Schottky junction is established between the Al electrode and the Si-μPs. The resulting flexible diodes show current levels on the order of mA for an area of 2 mm(2), a current rectification ratio up to 4 × 10(3) between 1 and 2 V bias and a cut-off frequency of 1.8 GHz. Energy harvesting experiments have been demonstrated using resistors as the load at 900 MHz and 1.8 GHz. The diode stack can be delaminated away from the Al electrode and then later on be transferred and reconfigured to another substrate. This provides us with reconfigurable GHz-operating diode circuits.

  2. High performance, environmentally friendly and low cost anodes for lithium-ion battery based on TiO 2 anatase and water soluble binder carboxymethyl cellulose

    Science.gov (United States)

    Mancini, M.; Nobili, F.; Tossici, R.; Wohlfahrt-Mehrens, M.; Marassi, R.

    The challenge of producing lithium-ion batteries meeting performance requirements and low environmental impact is strictly related to the choice of materials as well as to the manufacturing processes. Most electrodes are currently prepared using poly(vinilydene fluoride) (PVDF) as binder. This fluorinated polymer is expensive and requires the use of a volatile and toxic organic solvent such as N-methyl-pyrrolidone (NMP) in the processing. Water soluble sodium carboxymethyl cellulose (CMC) can be a suitable substitute for PVDF as binder for both anodes and cathodes eliminating the necessity of NMP and thus decreasing the cost and the environmental impact of battery production. In this work, CMC has been successfully used to prepare efficient and stable anatase TiO 2 anodes by optimizing the electrode manufacturing process in terms of composition and compression. The stability and the high rate performances of the TiO 2/CMC are described and compared with those of TiO 2/PVDF electrodes. The compatibility of the TiO 2/CMC with a LiFePO 4 cathode in a full-cell is also reported.

  3. Composition and Content of High-Molecular-Weight Glutenin Subunits and Their Effects on Wheat Quality

    Institute of Scientific and Technical Information of China (English)

    SONG Jian-min; LIU Ai-feng; WU Xiang-yun; LIU Jian-jun; ZHAO Zhen-dong; LIU Guang-tian

    2002-01-01

    Sedimentation values, flour glutenin macropolymer (GMP) contents, composition and contents of high-molecular-weight (HMW) glutenin subunits (GS) of 233 flour samples were determined. Our data indicated that subunit 1 occurred more frequently at Glu-A1, subunit pair 7 + 8 at Glu- B1 and 2 + 12 at Glu-D1. The significant relationships between Glu-1 quality score and total HMW glutenin content, sedimentation value and GMP content suggested that the composition of HMW-GS affects wheat quality strongly. Moreover,the total content of HMW-GS was correlated with certain quality parameters more significantly. Relationship between subunit 5 + 10 content and breadmaking quality was better than others, but 2 + 12, 7 + 8, 7 + 9 and 4 + 12 also correlated with certain quality parameters significantly. The contents of total HMW-glutenin, x-type subunits and y-type subunits related with sedimentation value, flour GMP content, and Glu-1 quality score more strongly than that of individual subunit or subunit pair. The flour GMP content, with excellent correlation to sedimentation value, total contents of HMW glutenin, x- and y-type subunits and many other quality parameters, could be an ideal indicator of breadmaking quality at earlier generations for breeding purpose for its simple procedure and small scale.

  4. High Seas High Schoolers: Creating ERESE Content on an Expedition to Samoa

    Science.gov (United States)

    Delaney, R.; English, B.; Staudigel, D.; Staudigel, H.; Koppers, A.; Hart, S.

    2005-12-01

    As part of the ERESE program, three high school seniors aboard the ALIA expedition generated contents and published a live trip website with a wide range of information about the science and personal aspects of the cruise. These activities served to relate as much meaningful information about the month-long research cruise in the South Pacific as possible, to people of all ages and skills. The website http://earthref.org/ERESE/projects/ALIA/ has reports on almost every aspect of the research cruise; from what it is like staying on the Research Vessel Kilo Moana for a month, to operating machinery, to interviews with the captain and chief scientists, and even how the equipment aboard works, in less than technical terms. An effective way to relay what was actually going on aboard the Kilo Moana, were the daily reports, written by the high school students, complete with the pictures and videos taken that day. This website connected the ALIA cruise to high school students and classrooms, who were following the expedition through the website both in the United States and in Samoa. High school seniors designed and implemented the "CruiseWatch" feature on the Alia website. This "applet" extracts data from the shipboard datastream and relays them to the ERESE website at the San Diego Supercomputing center via satellite, where they are prepared for real-time display on the cruise website. Data displayed include the ships' location on the map, geographic coordinates, heading, speed and wind speed. During dredging operations it displays the length of wire deployed, wire speed and wire tension. Overall the website with the daily reports and photographs, in addition to other web media, gave this trip a unique ability to engage people from around the world in researching oceanographic and geological phenomena.

  5. Adapting human pluripotent stem cells to high-throughput and high-content screening.

    Science.gov (United States)

    Desbordes, Sabrina C; Studer, Lorenz

    2013-01-01

    The increasing use of human pluripotent stem cells (hPSCs) as a source of cells for drug discovery, cytotoxicity assessment and disease modeling requires their adaptation to large-scale culture conditions and screening formats. Here, we describe a simple and robust protocol for the adaptation of human embryonic stem cells (hESCs) to high-throughput screening (HTS). This protocol can also be adapted to human induced pluripotent stem cells (hiPSCs) and high-content screening (HCS). We also describe a 7-d assay to identify compounds with an effect on hESC self-renewal and differentiation. This assay can be adapted to a variety of applications. The procedure involves the culture expansion of hESCs, their adaptation to 384-well plates, the addition of small molecules or other factors, and finally data acquisition and processing. In this protocol, the optimal number of hESCs plated in 384-well plates has been adapted to HTS/HCS assays of 7 d.

  6. Cellulosic fibril–rubber nanocomposites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2010-06-01

    Full Text Available Cellulose is the most abundant polymer on earth- has emerged as an ideal candidate for providing nanoparticles as reinforcing agents. There is a growing interest in cellulose nanocomposites within the research community and especially...

  7. Synthesis and properties of cellulose functionalized -4, 4'-(propane-2, 2'-diyl) diphenol-SiO2/TiO2 hybrid nanocomposites materials for high performance applications

    Science.gov (United States)

    Ramesh, Sivalingam; Kim, Gwang-Hoon; Kim, Heung-Soo; Kim, Jaehwan; Kim, Joo-Hyung

    2013-04-01

    The general class of organic-inorganic hybrid nanocomposites materials is a fast growing area of research. The significant effort is focused on the ability to control the nanoscale structures via organic functional synthetic approaches with inorganic metal oxides. The properties of nanocomposites material depends on the properties of their individual components but also their morphological and interfacial characteristics. This rapidly expanding field is generating many exciting new materials with novel properties. Mainly, cellulose is considered as the richest renewable materials are presently among the most promising candidates for use in photonics due to their versatility, flexibility, light weight, low cost and ease of modification. Cellulose-metal oxide nanomaterials were developed the technologies to manipulate selfassembly and multifunctionallity, of new technologies to the point where industry can produce advanced and costcompetitive cellulose metal oxide hybrid materials. Therefore, the present study is focused on cellulose-functionalized - 4, 4'-(propane-2, 2'-diyl) diphenol-SiO2/TiO2 hybrid nano-composites materials by in-situ sol-gel process. The chemical and morphological properties of cellulose-functionalized SiO2/TiO2 materials via covalent crosslinking hybrids were characterized by FTIR, XRD, TGA, DSC, SEM, TEM and optical properties.

  8. The cellulose resource matrix.

    Science.gov (United States)

    Keijsers, Edwin R P; Yılmaz, Gülden; van Dam, Jan E G

    2013-03-01

    The emerging biobased economy is causing shifts from mineral fossil oil based resources towards renewable resources. Because of market mechanisms, current and new industries utilising renewable commodities, will attempt to secure their supply of resources. Cellulose is among these commodities, where large scale competition can be expected and already is observed for the traditional industries such as the paper industry. Cellulose and lignocellulosic raw materials (like wood and non-wood fibre crops) are being utilised in many industrial sectors. Due to the initiated transition towards biobased economy, these raw materials are intensively investigated also for new applications such as 2nd generation biofuels and 'green' chemicals and materials production (Clark, 2007; Lange, 2007; Petrus & Noordermeer, 2006; Ragauskas et al., 2006; Regalbuto, 2009). As lignocellulosic raw materials are available in variable quantities and qualities, unnecessary competition can be avoided via the choice of suitable raw materials for a target application. For example, utilisation of cellulose as carbohydrate source for ethanol production (Kabir Kazi et al., 2010) avoids the discussed competition with easier digestible carbohydrates (sugars, starch) deprived from the food supply chain. Also for cellulose use as a biopolymer several different competing markets can be distinguished. It is clear that these applications and markets will be influenced by large volume shifts. The world will have to reckon with the increase of competition and feedstock shortage (land use/biodiversity) (van Dam, de Klerk-Engels, Struik, & Rabbinge, 2005). It is of interest - in the context of sustainable development of the bioeconomy - to categorize the already available and emerging lignocellulosic resources in a matrix structure. When composing such "cellulose resource matrix" attention should be given to the quality aspects as well as to the available quantities and practical possibilities of processing the

  9. Recent Development in Spectroscopic and Chemical Characterization of Cellulose

    Science.gov (United States)

    2005-01-01

    purify tap water partly in place of chlorination. When pulps having lower a-cellulose content are used, some acetone -insoluble gel fractions originating...aqueous NaOH) by reacting with etherifying reagents around 60°C in the presence of i -propanol or i - butanol , where etherifications proceed...Cellouronic acid Na salt was prepared from viscose rayon by the TEMPO-mediated oxidation. fermentation . Susceptibility of cellulosic materials to acid

  10. Methods of detection using a cellulose binding domain fusion product

    Energy Technology Data Exchange (ETDEWEB)

    Shoseyov, Oded (Shimshon, IL); Shpiegl, Itai (North Gallilea, IL); Goldstein, Marc A. (Davis, CA); Doi, Roy H. (Davis, CA)

    1999-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  11. Methods of use of cellulose binding domain proteins

    Science.gov (United States)

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc A.; Doi, Roy H.

    1997-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  12. REQUIREMENT OF FLUIDITY OF HIGH WATER CONTENT MATERIALS FORTHE GETWAY-SIDE BACKFILLING TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    QiTaiyue; MaNianjie

    1996-01-01

    Through analyzing the effects of water consumption, diameter of solid particle, and flow velocity on the fluidity of high water content material slurry, the relationship among the fluidity, the isotropy of the slurry, and the pumping facilities applied in getway-side backfilling has been found. And the requirment of fluidity of high water content material for the design of getway-side backfilling technique is put forward in the paper.

  13. A degradation model for high kitchen waste content municipal solid waste.

    Science.gov (United States)

    Chen, Yunmin; Guo, Ruyang; Li, Yu-Chao; Liu, Hailong; Zhan, Tony Liangtong

    2016-12-01

    Municipal solid waste (MSW) in developing countries has a high content of kitchen waste (KW), and therefore contains large quantities of water and non-hollocellulose degradable organics. The degradation of high KW content MSW cannot be well simulated by the existing degradation models, which are mostly established for low KW content MSW in developed countries. This paper presents a two-stage anaerobic degradation model for high KW content MSW with degradations of hollocellulose, sugars, proteins and lipids considered. The ranges of the proportions of chemical compounds in MSW components are summarized with the recommended values given. Waste components are grouped into rapidly or slowly degradable categories in terms of the degradation rates under optimal water conditions for degradation. In the proposed model, the unionized VFA inhibitions of hydrolysis/acidogenesis and methanogenesis are considered as well as the pH inhibition of methanogenesis. Both modest and serious VFA inhibitions can be modeled by the proposed model. Default values for the parameters in the proposed method can be used for predictions of degradations of both low and high KW content MSW. The proposed model was verified by simulating two laboratory experiments, in which low and high KW content MSW were used, respectively. The simulated results are in good agreement with the measured data of the experiments. The results show that under low VFA concentrations, the pH inhibition of methanogenesis is the main inhibition to be considered, while the inhibitions of both hydrolysis/acidogenesis and methanogenesis caused by unionized VFA are significant under high VFA concentrations. The model is also used to compare the degradation behaviors of low and high KW content MSW under a favorable environmental condition, and it shows that the gas potential of high KW content MSW releases more quickly.

  14. Loosening Xyloglucan Accelerates the Enzymatic Degradation of Cellulose in Wood

    Institute of Scientific and Technical Information of China (English)

    Rumi Kaida; Tomomi Kaku; Kei'ichi Baba; Masafumi Oyadomari; Takashi Watanabe; Koji Nishida; Toshiji Kanaya; Ziv Shani; Oded Shoseyov; Takahisa Hayashi

    2009-01-01

    In order to create trees in which cellulose, the most abundant component in biomass, can be enzymatically hydrolyzed highly for the production of bioethanol, we examined the saccharification of xylem from several transgenic poplars, each overexpressing either xyloglucanase, cellulase, xylanase, or galactanase. The level of cellulose degradation achieved by a cellulase preparation was markedly greater in the xylem overexpressing xyloglucanase and much greater in the xylems overexpressing xylanase and cellulase than in the xylem of the wild-type plant. Although a high degree of degradation occurred in all xylems at all loci, the crystalline region of the cellulose microfibrUs was highly degraded in the xylem overexpressing xyloglucanase. Since the complex between microfibrils and xyloglucans could be one region that is particularly resistant to cellulose degradation, loosening xyloglucan could facilitate the enzymatic hydrolysis of cellulose in wood.

  15. Aspen Tension Wood Fibers Contain β-(1---> 4)-Galactans and Acidic Arabinogalactans Retained by Cellulose Microfibrils in Gelatinous Walls.

    Science.gov (United States)

    Gorshkova, Tatyana; Mokshina, Natalia; Chernova, Tatyana; Ibragimova, Nadezhda; Salnikov, Vadim; Mikshina, Polina; Tryfona, Theodora; Banasiak, Alicja; Immerzeel, Peter; Dupree, Paul; Mellerowicz, Ewa J

    2015-11-01

    Contractile cell walls are found in various plant organs and tissues such as tendrils, contractile roots, and tension wood. The tension-generating mechanism is not known but is thought to involve special cell wall architecture. We previously postulated that tension could result from the entrapment of certain matrix polymers within cellulose microfibrils. As reported here, this hypothesis was corroborated by sequential extraction and analysis of cell wall polymers that are retained by cellulose microfibrils in tension wood and normal wood of hybrid aspen (Populus tremula × Populus tremuloides). β-(1→4)-Galactan and type II arabinogalactan were the main large matrix polymers retained by cellulose microfibrils that were specifically found in tension wood. Xyloglucan was detected mostly in oligomeric form in the alkali-labile fraction and was enriched in tension wood. β-(1→4)-Galactan and rhamnogalacturonan I backbone epitopes were localized in the gelatinous cell wall layer. Type II arabinogalactans retained by cellulose microfibrils had a higher content of (methyl)glucuronic acid and galactose in tension wood than in normal wood. Thus, β-(1→4)-galactan and a specialized form of type II arabinogalactan are trapped by cellulose microfibrils specifically in tension wood and, thus, are the main candidate polymers for the generation of tensional stresses by the entrapment mechanism. We also found high β-galactosidase activity accompanying tension wood differentiation and propose a testable hypothesis that such activity might regulate galactan entrapment and, thus, mechanical properties of cell walls in tension wood.

  16. Enhanced ethanol fermentation by engineered Saccharomyces cerevisiae strains with high spermidine contents.

    Science.gov (United States)

    Kim, Sun-Ki; Jo, Jung-Hyun; Jin, Yong-Su; Seo, Jin-Ho

    2017-05-01

    Construction of robust and efficient yeast strains is a prerequisite for commercializing a biofuel production process. We have demonstrated that high intracellular spermidine (SPD) contents in Saccharomyces cerevisiae can lead to improved tolerance against various fermentation inhibitors, including furan derivatives and acetic acid. In this study, we examined the potential applicability of the S. cerevisiae strains with high SPD contents under two cases of ethanol fermentation: glucose fermentation in repeated-batch fermentations and xylose fermentation in the presence of fermentation inhibitors. During the sixteen times of repeated-batch fermentations using glucose as a sole carbon source, the S. cerevisiae strains with high SPD contents maintained higher cell viability and ethanol productivities than a control strain with lower SPD contents. Specifically, at the sixteenth fermentation, the ethanol productivity of a S. cerevisiae strain with twofold higher SPD content was 31% higher than that of the control strain. When the SPD content was elevated in an engineered S. cerevisiae capable of fermenting xylose, the resulting S. cerevisiae strain exhibited much 40-50% higher ethanol productivities than the control strain during the fermentations of synthetic hydrolysate containing high concentrations of fermentation inhibitors. These results suggest that the strain engineering strategy to increase SPD content is broadly applicable for engineering yeast strains for robust and efficient production of ethanol.

  17. POLYETHERSULFONE COMPOSITE MEMBRANE BLENDED WITH CELLULOSE FIBRILS

    Directory of Open Access Journals (Sweden)

    Ping Qu

    2010-09-01

    Full Text Available Polyethersulfone (PES is a common material used for ultrafiltration (UF membranes, which has good chemical resistance, high mechanical properties, and wide temperature tolerances. The hydrophobic property of the PES membrane seriously limits its application. Cellulose fibrils are composed of micro-sized and nano-sized elements, which have high hydrophilicity, strength, and biodegradation. A composite membrane was prepared by the phase inversion induced by an immersion process. The characteristics of the composite membrane were investigated with Fourier transform infrared spectroscopy (FTIR, X-ray diffraction (XRD, thermogravimetric analysis (TGA, and atomic force microscopy (AFM. The pure water flux of the composite membrane increased dramatically with the increase of cellulose firbils. Mean pore size and porosity were significantly increased. Both mechanical properties and hydrophilicity were enhanced due to the addition of the cellulose firbils.

  18. Pretreatment of cellulosic biomass in improved production of ethanol and chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Ningjun; Gong, C.S.; Tsao, G.T. [Purdue Univ., West Lafayette, IN (United States); Yutang Huang [Jilin Corn Research and Development Center (China)

    1996-12-31

    A highly efficient process of simultaneous saccharification and fermentation (SSF) of cellulose using fungal cellulose and yeast to produce ethanol from lignocellulose pretreated with ammonia was developed. The process entails steeping the biomass with ammonia at ambient temperature to remove and extract lignin. This is followed by dilute acid hydrolysis at 100-108{degrees}C under atmospheric pressure to remove and recover a xylose-rich hemicellulose fraction as hemicellulose hydrolysate. This xylose-rich (92% xylose) hydrolysate was used as substrate for xylitol production by yeast and cellulose fraction was used for ethanol production in the SSF process with yeast. The same substrate was also used for 2,3-butanediol production in the SSF process with Klebsiella pneumonia. Experiments show that 98% of ammonia is recoverable for reuse and that the treated ground corn cob gives close to 86% theoretical yield of ethanol based on cellulose content. An ethanol concentration of over 60 g/L was obtained within 72 hours of SSF. 8 refs., 7 figs.

  19. Influence of Cellulosic Binders on Sensitivity and Combustion Behaviour of B-KNO3 Ignition System

    Directory of Open Access Journals (Sweden)

    Varsha Bhingarkar

    2006-07-01

    Full Text Available Boron-potassium nitrate (B-KNO3-based compositions have been used as an effective ignitersystem for solid rocket propellants. A systematic study was undertaken to generate exhaustivedata on B-KNO3 (25:65-based ignition systems with cellulosic binders, viz., nitrocellulose, ethylcellulose and plasticised ethyl cellulose. In addition, detailed investigations were carried outwith PEC as binder by varying its concentration from 2-10 per cent in the same system. Theexperimental compositions (B-KNO3: binder were evaluated by closed-vessel firing, thermalanalysis, sensitivity, mechanical properties and cal-val determination. The binders significantlyinfluenced the sensitivity and combustion behaviour of B-KNO3 compositions. The compositionwith nitrocellulose as binder produced high flame temperature and cal-val as compared to ethylcellulose and plasticised ethyl cellulose-based compositions. The data indicated that thecalculated flame temperature for all compositions was in the range 2716 K to 2957 K. As theplasticised ethyl cellulose content increased from 2 per cent to 10 per cent, the maximum pressureincreased with decrease in heat of combustion.

  20. Development of a New Foxtail Millet Germplasm with Super Early Maturity and High Iron Content

    Institute of Scientific and Technical Information of China (English)

    LIU Zheng-li; SUN Shi-xian; CHENG Ru-hong; HUANG Wen-sheng; LIU Jun-xin; QU Zhu-feng; XIA Xue-yan; SHI Zhi-gang

    2006-01-01

    Super Early Maturation No.2 is a new foxtail millet germplasm developed by using the targeted-character-gene-bankbreeding method. It has several outstanding characteristics. (1) Super early maturity. It can normally mature in Bashang,Hebei Province, China, where the altitude is around 1 400 meters, and it needs 1 650℃ of effective accumulated temperature in the growing period. (2) Millet is rich in iron. The iron content of the millet of Super Early Maturation No.2 is 54.10 mg kg-1,which is 62.0% higher than the average iron content of the foxtail millet varieties in China. (3) High crude fat content. Its crude fat content is 6.24%, which is 54.1% higher than the average content of foxtail millet varieties in China. (4) High crude protein content. The average of the crude protein content of all the foxtail millet varieties in China is 12.71%, only5% varieties surpass 14%, however, the crude protein content of Super Early Maturation No.2 is 14.36%, which is rare in improved varieties of foxtail millet in China. (5) Overall characteristics are good.

  1. SILYLATION OF CELLULOSE WITH TRICHLOROSILANE AND TRIETHOXYSILANE IN HOMOGENEOUS LiCl/ N,N-DIMETHYLACETAMIDE SOLUTION

    Institute of Scientific and Technical Information of China (English)

    Hai-qing Liu; Li-na Zhang

    2000-01-01

    Silyl celluloses (SiC) were prepared by reacting cellulose with chloropropyltrichlorosilane (CPTCSi) and chloropropyltriethoxysilane (CPTESi) in LiCl/N,N-dimethylacetamide (DMAc). The Si content in the silyl cellulose could be controlled by adjustment of the molar ratio of silane and cellulose. FT-IR spectra showed that cellulose was readily reacted with the above two silane reagents, and the reactivity of CPTCSi is higher than that of CPTESi. It was presumed that the reaction process belongs to graft-polymerization. The results of differential thermal analysis (DTA) indicated that the thermostability of the materials produced increased with the increase of Si content in the sample. The acid resistance of the samples SiC in 1 mol/L HCl aqueous solution was improved significantly. When Si content was ca. 20%, the silyl cellulose has excellent thermostability, hydrophobicity, low density and stability in 1 mol/L HCl aqueous solution, owing to crosslinking of cellulose chain with silane.

  2. Production and effect of aldonic acids during enzymatic hydrolysis of lignocellulose at high dry matter content

    DEFF Research Database (Denmark)

    Cannella, David; Hsieh, Chia-Wen; Felby, Claus;

    2012-01-01

    conversion yields. When using pure cellulose substrates it has been determined that both oxidized and unoxidized cellodextrin products are formed. We report the effect of oxidative activity in a commercial enzyme mix (Cellic CTec2) upon overall hydrolysis, formation of oxidized products and impact on ß......-glucosidase than glucose. The formation of oxidized products decreased as the hydrolysis temperature was increased from 33° to 50°C. Despite end-product inhibition, the oxidative cleavage of the cellulose chains has a synergistic effect upon the overall hydrolysis of cellulose as the sugar yield increased compared...... hydrolysis of pretreated wheat straw at 30% WIS. Up to 4% of released glucose was oxidized into gluconic acid using Cellic CTec2, whereas no oxidized products were detected when using an earlier cellulase preparation Celluclast/Novozym188. However, the cellulose conversion yield was 25% lower using...

  3. Production and effect of aldonic acids during enzymatic hydrolysis of lignocellulose at high dry matter content

    DEFF Research Database (Denmark)

    Cannella, David; Hsieh, Chia-Wen; Felby, Claus

    2012-01-01

    hydrolysis of pretreated wheat straw at 30% WIS. Up to 4% of released glucose was oxidized into gluconic acid using Cellic CTec2, whereas no oxidized products were detected when using an earlier cellulase preparation Celluclast/Novozym188. However, the cellulose conversion yield was 25% lower using......, no reducing agent was needed for the function of the oxidative enzymes. Conclusions: The presence of oxidative enzymes in Cellic CTec2 led to the formation of cellobionic and gluconic acid during hydrolysis of pretreated wheat straw and filter paper. Gluconic acid was a stronger inhibitor of ß......Abstract Background: The recent discovery of accessory proteins that boost cellulose hydrolysis has increased the economical and technical efficiency of processing cellulose to bioethanol. Oxidative enzymes (e.g. GH61) present in new commercial enzyme preparations have shown to increase cellulose...

  4. High-content screening of yeast mutant libraries by shotgun lipidomics

    DEFF Research Database (Denmark)

    Tarasov, Kirill; Stefanko, Adam; Casanovas, Albert;

    2014-01-01

    To identify proteins with a functional role in lipid metabolism and homeostasis we designed a high-throughput platform for high-content lipidomic screening of yeast mutant libraries. To this end, we combined culturing and lipid extraction in 96-well format, automated direct infusion nanoelectrosp......To identify proteins with a functional role in lipid metabolism and homeostasis we designed a high-throughput platform for high-content lipidomic screening of yeast mutant libraries. To this end, we combined culturing and lipid extraction in 96-well format, automated direct infusion...... factor KAR4 precipitated distinct lipid metabolic phenotypes. These results demonstrate that the high-throughput shotgun lipidomics platform is a valid and complementary proxy for high-content screening of yeast mutant libraries....

  5. Understanding the Role of Physical Properties of Cellulose on Its Hydrolyzability by Cellulases

    Science.gov (United States)

    O'Dell, Patrick Jonathan

    Cellulose has long been explored as a potential feedstock for biofuel, however the recalcitrance of cellulose makes its conversion into biofuel much more challenging and economically unfavorable compared to well-established processes for converting starch or sugar feedstocks into biofuel. Enzymes capable of hydrolyzing cellulose into soluble sugars, glucose and cellobiose, have been found to work processively along cellulose microfibrils starting from reducing end groups. For this study, cellulose was produced and purified in-house from Gluconacetobacter xylinum cultures, and characterized by quantifying functional groups (aldehyde, ketone, and carboxyl groups) to determine the extent of oxidation of cellulose due to the processing steps. The main goal of this study was to look at the impacts of ultrasonication on cellulose's structure and the enzymatic hydrolyzability of cellulose. A completely randomized experimental design was used to test the effect of ultrasonication time and amplitude (intensity) on changes in cellulose fibril length, degree of polymerization, and rates and extents of hydrolysis. Results indicated that sonication time does significantly impact both the fibril length and average degree of polymerization of cellulose. The impact of ultrasonication on the hydrolyzability of cellulose by commercial cellulase and beta-glucosidase preparations could not be effectively resolved due to high variability in the experimental results. These studies serve as a basis for future studies understanding the role of cellulose microstructure in the mechanism of cellulase hydrolysis of cellulose.

  6. Electrochemical Properties of LLTO/Fluoropolymer-Shell Cellulose-Core Fibrous Membrane for Separator of High Performance Lithium-Ion Battery

    OpenAIRE

    Fenglin Huang; Wenting Liu; Peiying Li; Jinxia Ning; Qufu Wei

    2016-01-01

    A superfine Li0.33La0.557TiO3 (LLTO, 69.4 nm) was successfully synthesized by a facile solvent-thermal method to enhance the electrochemical properties of the lithium-ion battery separator. Co-axial nanofiber of cellulose and Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) was prepared by a co-axial electrospinning technique, in which the shell material was PVDF-HFP and the core was cellulose. LLTO superfine nanoparticles were incorporated into the shell of the PVDF-HFP. The core–...

  7. PREPARATION AND CHARACTERIZATION OF BAMBOO NANOCRYSTALLINE CELLULOSE

    Directory of Open Access Journals (Sweden)

    Mengjiao Yu,

    2012-02-01

    Full Text Available Nanocrystalline cellulose (NCC has many potential applications because of its special properties. In this paper, NCC was prepared from bamboo pulp. Bamboo pulp was first pretreated with sodium hydroxide, followed by hydrolysis with sulfuric acid. The concentration of sulfuric acid and the hydrolysis time on the yield of NCC were studied. The results showed that sulfuric acid concentration had larger influence than the hydrolysis time on the yield of NCC. When the temperature was 50oC, the concentration of sulfuric acid was 48wt% and the reaction time was 30 minutes, a high quality of nanocrystalline cellulose was obtained; under these conditions, the length of the nanocrystalline cellulose ranged from 200 nm to 500 nm, the diameter was less than 20 nm, the yield was 15.67wt%, and the crystallinity was 71.98%, which is not only higher than those of cellulose nanocrystals prepared from some non-wood materials, but also higher than bamboo cellulose nanocrystals prepared by other methods.

  8. Molecular-scale investigations of cellulose microstructure during enzymatic hydrolysis.

    Science.gov (United States)

    Santa-Maria, Monica; Jeoh, Tina

    2010-08-09

    Changes in cellulose microstructure have been proposed to occur throughout hydrolysis that impact enzyme access and hydrolysis rates. However, there are very few direct observations of such changes in ongoing reactions. In this study, changes in the microstructure of cellulose are measured by simultaneous confocal and atomic force microscopy and are correlated to hydrolysis extents and quantities of bound enzyme in the reaction. Minimally processed and never-dried cellulose I was hydrolyzed by a purified cellobiohydrolase, Trichoderma reesei Cel7A. Early in the reaction ( approximately 30% hydrolysis), at high hydrolysis rates and high bound cellulase quantities, untwisting of cellulose microfibrils was observed. As the hydrolysis reaction neared completion (>80% hydrolysis), extensively thinned microfibrils (diameters of 3-5 nm) and channels (0.3-0.6 nm deep) along the lengths of the microfibrils were observed. The prominent microstructural changes in cellulose due to cellobiohydrolase action are discussed in the context of the overall hydrolysis reaction.

  9. Tensile and characterization properties of regenerated cellulose empty fruit bunch biocomposite films using ionic liquid

    Science.gov (United States)

    Husseinsyah, Salmah; Zailuddin, Nur Liyana Izyan; Li, Chew Li; Mostapha @ Zakaria, Marliza

    2016-07-01

    The regenerated cellulose (RC) empty fruit bunch (EFB) biocomposite films were prepared using ionic liquid. The tensile strength and modulus of elasticity of regenerated cellulose biocomposite films achieved maximum value at 2 wt% of EFB contents while at 3 and 4 wt% of EFB the tensile strength and modulus of elasticity tend to decreased. The elongation at break tends to decreased at 2 wt% of EFB content but increased at 3 and 4 wt% of EFB contents. The crystallinity index reaches maximum at 2 wt% EFB content, followed by declination with further addition of EFB content. The morphology study illustrated that regenerated cellulose biocomposite films at 2 wt% of EFB contents exhibit a smooth surface that suggested the reinforcement was surrounded by the regenerated cellulose matrix, while at 4 wt% EFB content shows a rough morphology.

  10. The cellulose resource matrix

    NARCIS (Netherlands)

    Keijsers, E.R.P.; Yilmaz, G.; Dam, van J.E.G.

    2013-01-01

    The emerging biobased economy is causing shifts from mineral fossil oil based resources towards renewable resources. Because of market mechanisms, current and new industries utilising renewable commodities, will attempt to secure their supply of resources. Cellulose is among these commodities, where

  11. Calculating cellulose diffraction patterns

    Science.gov (United States)

    Although powder diffraction of cellulose is a common experiment, the patterns are not widely understood. The theory is mathematical, there are numerous different crystal forms, and the conventions are not standardized. Experience with IR spectroscopy is not directly transferable. An awful error, tha...

  12. The cellulose resource matrix

    NARCIS (Netherlands)

    Keijsers, E.R.P.; Yilmaz, G.; Dam, van J.E.G.

    2013-01-01

    The emerging biobased economy is causing shifts from mineral fossil oil based resources towards renewable resources. Because of market mechanisms, current and new industries utilising renewable commodities, will attempt to secure their supply of resources. Cellulose is among these commodities, where

  13. Cellulose fibers extracted from rice and oat husks and their application in hydrogel.

    Science.gov (United States)

    Oliveira, Jean Paulo de; Bruni, Graziella Pinheiro; Lima, Karina Oliveira; Halal, Shanise Lisie Mello El; Rosa, Gabriela Silveira da; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

    2017-04-15

    The commercial cellulose fibers and cellulose fibers extracted from rice and oat husks were analyzed by chemical composition, morphology, functional groups, crystallinity and thermal properties. The cellulose fibers from rice and oat husks were used to produce hydrogels with poly (vinyl alcohol). The fibers presented different structural, crystallinity, and thermal properties, depending on the cellulose source. The hydrogel from rice cellulose fibers had a network structure with a similar agglomeration sponge, with more homogeneous pores compared to the hydrogel from oat cellulose fibers. The hydrogels prepared from the cellulose extracted from rice and oat husks showed water absorption capacity of 141.6-392.1% and high opacity. The highest water absorption capacity and maximum stress the compression were presented by rice cellulose hydrogel at 25°C. These results show that the use of agro-industrial residues is promising for the biomaterial field, especially in the preparation of hydrogels.

  14. Effect of high temperature and excessive light on glutathione content in apple peel

    Institute of Scientific and Technical Information of China (English)

    Jianguang ZHANG; Shaochun CHEN; Yingli LI; Bao DI; Jianqiang ZHANG; Yufang LIU

    2008-01-01

    The present experiment was conducted to examine the changing patterns of glutathione (GSH) contents in apple peel stressed by high temperature and excessive solar radiation. By comparing the parameters of temperature and light conditions where fruits grow with the GSH contents in them, the mutual relationship was disclosed. Meanwhile, the changes of antioxidant capacity of fruits stressed at different levels were studied under artificially controlled conditions in a laboratory. Also, the effect of applying various types of exogenous substances was evaluated on endogenous GSH contents. The results indicated that within a certain range, a positive correlation was found between the stressed extents to which fruits were subject by high temperature and exces-sive light, and GSH contents in fruit peel. Moreover, fruits on southwest (SW) exposure contained a very significantly higher amount of GSH than those on other exposures. In laboratory experiments, it was proved that fruit GSH contents increased with temperatures within a certain range but they declined beyond a given limit. The temperature rising modes had a great influence on fruit GSH contents, and gradual tem-perature increase was favorable to an increase of antioxidant capability in fruit peel, thus providing a theoretical basis for exerting appropriate acclimation on fruits. It was also docu-mented that application of four exogenous formulations could significantly increase the endogenous GSH contents, among which AsA (ascorbit acid)+BA (benzoic acid) and SA (sali-cylic acid) treatments exhibited better results, 33.97% and 31.81% higher than the control, respectively.

  15. Regenerating cellulose from ionic liquids for an accelerated enzymatic hydrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Hua [Savannah State University; Jones, Cecil L [Savannah State University; Baker, Gary A [ORNL; Xia, Shuqian [Tianjin University, Tianjin, China; Olubajo, Olarongbe [Savannah State University; Person, Vernecia [Savannah State University

    2009-01-01

    cellulose, filter paper and cottonwere hydrolyzed 2 10 times faster than the respective untreated celluloses. A complete hydrolysis of Avicel cellulose could be achieved in 6 h given the Trichoderma reesei cellulase/substrate ratio (w/w) of 3:20 at 50 C. In addition,we observed that cellulase is more thermally stable (up to 60 C) in the presence of regenerated cellulose. Furthermore, our systematic studies suggest that the presence of various ILs during the hydrolysis induced different degrees of cellulase inactivation. Therefore, a thorough removal of IL residues after cellulose regeneration is highly recommended, and a systematic investigation on this subject is much needed.

  16. High strength, flexible and transparent nanofibrillated cellulose-nanoclay biohybrid films with tunable oxygen and water vapor permeability.

    Science.gov (United States)

    Aulin, Christian; Salazar-Alvarez, German; Lindström, Tom

    2012-10-21

    A novel, technically and economically benign procedure to combine vermiculite nanoplatelets with nanocellulose fibre dispersions into functional biohybrid films is presented. Nanocellulose fibres of 20 nm diameters and several micrometers in length are mixed with high aspect ratio exfoliated vermiculite nanoplatelets through high-pressure homogenization. The resulting hybrid films obtained after solvent evaporation are stiff (tensile modulus of 17.3 GPa), strong (strength up to 257 MPa), and transparent. Scanning electron microscopy (SEM) shows that the hybrid films consist of stratified nacre-like layers with a homogenous distribution of nanoplatelets within the nanocellulose matrix. The oxygen barrier properties of the biohybrid films outperform commercial packaging materials and pure nanocellulose films showing an oxygen permeability of 0.07 cm(3) μm m(-2) d(-1) kPa(-1) at 50% relative humidity. The oxygen permeability of the hybrid films can be tuned by adjusting the composition of the films. Furthermore, the water vapor barrier properties of the biohybrid films were also significantly improved by the addition of nanoclay. The unique combination of excellent oxygen barrier behavior and optical transparency suggests the potential of these biohybrid materials as an alternative in flexible packaging of oxygen sensitive devices such as thin-film transistors or organic light-emitting diode displays, gas storage applications and as barrier coatings/laminations in large volume packaging applications.

  17. High concentrations of cellulosic ethanol achieved by fed batch semi simultaneous saccharification and fermentation of waste-paper.

    Science.gov (United States)

    Elliston, Adam; Collins, Samuel R A; Wilson, David R; Roberts, Ian N; Waldron, Keith W

    2013-04-01

    A fundamental goal of second generation ethanol production is to increase the ethanol concentration to 10% (v/v) or more to optimise distillation costs. Semi simultaneous saccharification and fermentations (SSSF) were conducted at small pilot scale (5L) utilising fed-batch additions of solid shredded copier paper substrate. Early addition of Accellerase® 1500 at 16 FPU/g substrate and 30 U/g β-glucosidase followed by substrate only batch addition allowed low final equivalent enzyme concentrations to be achieved (3.7 FPU/g substrate) whilst maintaining digestion. Batch addition resulted in a cumulative substrate concentration equivalent to 65% (w/v). This in turn resulted in the production of high concentrations of ethanol (11.6% v/v). The success of this strategy relied on the capacity of the bioreactor to perform high shear mixing as required. Further research into the timing and number of substrate additions could lead to further improvement in overall yields from the 65.5% attained. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Unearthing the Ecology of Soil Microorganisms Using a High Resolution DNA-SIP Approach to Explore Cellulose and Xylose Metabolism in Soil.

    Science.gov (United States)

    Pepe-Ranney, Charles; Campbell, Ashley N; Koechli, Chantal N; Berthrong, Sean; Buckley, Daniel H

    2016-01-01

    We explored microbial contributions to decomposition using a sophisticated approach to DNA Stable Isotope Probing (SIP). Our experiment evaluated the dynamics and ecological characteristics of functionally defined microbial groups that metabolize labile and structural C in soils. We added to soil a complex amendment representing plant derived organic matter substituted with either (13)C-xylose or (13)C-cellulose to represent labile and structural C pools derived from abundant components of plant biomass. We found evidence for (13)C-incorporation into DNA from (13)C-xylose and (13)C-cellulose in 49 and 63 operational taxonomic units (OTUs), respectively. The types of microorganisms that assimilated (13)C in the (13)C-xylose treatment changed over time being predominantly Firmicutes at day 1 followed by Bacteroidetes at day 3 and then Actinobacteria at day 7. These (13)C-labeling dynamics suggest labile C traveled through different trophic levels. In contrast, microorganisms generally metabolized cellulose-C after 14 days and did not change to the same extent in phylogenetic composition over time. Microorganisms that metabolized cellulose-C belonged to poorly characterized but cosmopolitan soil lineages including Verrucomicrobia, Chloroflexi, and Planctomycetes.

  19. Chimeric lactase capable of spontaneous and strong immobilization on cellulose and development of a continuous-flow system for lactose hydrolysis at high temperatures.

    Science.gov (United States)

    Velikodvorskaya, G A; Tikhonova, T V; Gurvits, I D; Karyagina, A S; Lavrova, N V; Sergienko, O V; Tashlitskii, V N; Lunina, N A; Lunin, V G

    2010-12-01

    Recombinant plasmids containing fusion proteins composed of two different modules were constructed and expressed in Escherichia coli. The modules encoded the lactase LacA (LacZ) from the thermophilic bacterium Thermoanaerobacter ethanolicus and the cellulase CelD, a cellulose-binding module (CBM) from Anaerocellum thermophilum. The CelD CBM provides a spontaneous and strong sorption of the fusion proteins onto a cellulose carrier. The enzymatic activities of both the free LacA protein and LacA-CelD CBM fusion proteins immobilized onto the cellulose carrier were assessed. The LacA activity of the fusion protein was dependent upon its position with respect to the CBM. The highest level of lactase activity and stability was observed when the lactase domain was localized at its N terminus. A continuous-flow column reactor of lactase immobilized on a cellulose carrier was constructed, and its activity was assessed. The lactose hydrolysis rate for a 150 mM (5%) solution at a flow rate of 1 reactor volume per min was 75%, which is a value optimal for further whey transformation into glucose/galactose syrup.

  20. Unearthing the ecology of soil microorganisms using a high resolution DNA-SIP approach to explore cellulose and xylose metabolism in soil

    Directory of Open Access Journals (Sweden)

    Charles ePepe-Ranney

    2016-05-01

    Full Text Available We explored microbial contributions to decomposition using a sophisticated approach to DNA Stable Isotope Probing (SIP. Our experiment evaluated the dynamics and ecological characteristics of functionally defined microbial groups that metabolize labile and structural C in soils. We added to soil a complex amendment representing plant derived organic matter substituted with either 13C-xylose or 13C-cellulose to represent labile and structural C pools derived from abundant components of plant biomass. We found evidence for 13C-incorporation into DNA from 13C-xylose and 13C-cellulose in 49 and 63 operational taxonomic units (OTUs, respectively. The types of microorganisms that assimilated 13C in the 13C-xylose treatment changed over time being predominantly Firmicutes at day 1 followed by Bacteroidetes at day 3 and then Actinobacteria at day 7. These 13C-labeling dynamics suggest labile C traveled through different trophic levels. In contrast, microorganisms generally metabolized cellulose-C after 14 days and did not change to the same extent in phylogenetic composition over time. Microorganisms that metabolized cellulose-C belonged to poorly characterized but cosmopolitan soil lineages including Verrucomicrobia, Chloroflexi and Planctomycetes.

  1. Optimisation of rubberised concrete with high rubber content: an experimental investigation

    OpenAIRE

    Raffoul, S.; Garcia, R; Pilakoutas, K.; Guadagnini, M.; Flores Medina, N.

    2016-01-01

    This article investigates experimentally the behaviour of rubberised concrete (RuC) with high rubber content so as to fully utilise the mechanical properties of vulcanised rubber. The fresh properties and short-term uniaxial compressive strength of 40 rubberised concrete mixes were assessed. The parameters examined included the volume (0–100%) and type of mineral aggregate replacement (fine or coarse), water or admixture contents, type of binder, rubber particle properties, and rubber surface...

  2. Recycling cellulases for cellulosic ethanol production at industrial relevant conditions: potential and temperature dependency at high solid processes.

    Science.gov (United States)

    Lindedam, Jane; Haven, Mai Østergaard; Chylenski, Piotr; Jørgensen, Henning; Felby, Claus

    2013-11-01

    Different versions of two commercial cellulases were tested for their recyclability of enzymatic activity at high dry matter processes (12% or 25% DM). Recyclability was assessed by measuring remaining enzyme activity in fermentation broth and the ability of enzymes to hydrolyse fresh, pretreated wheat straw. Industrial conditions were used to study the impact of hydrolysis temperature (40 or 50°C) and residence time on recyclability. Enzyme recycling at 12% DM indicated that hydrolysis at 50°C, though ideal for ethanol yield, should be kept short or carried out at lower temperature to preserve enzymatic activity. Best results for enzyme recycling at 25% DM was 59% and 41% of original enzyme load for a Celluclast:Novozyme188 mixture and a modern cellulase preparation, respectively. However, issues with stability of enzymes and their strong adsorption to residual solids still pose a challenge for applicable methods in enzyme recycling.

  3. Brassinosteroids can regulate cellulose biosynthesis by controlling the expression of CESA genes in Arabidopsis

    OpenAIRE

    Xie, Liqiong; Yang, Cangjing; Wang, Xuelu

    2011-01-01

    The phytohormones, brassinosteroids (BRs), play important roles in regulating cell elongation and cell size, and BR-related mutants in Arabidopsis display significant dwarf phenotypes. Cellulose is a biopolymer which has a major contribution to cell wall formation during cell expansion and elongation. However, whether BRs regulate cellulose synthesis, and if so, what the underlying mechanism of cell elongation induced by BRs is, is unknown. The content of cellulose and the expression levels o...

  4. High and Low Consensus Groups: A Content and Relational Interaction Analysis.

    Science.gov (United States)

    DeStephen, Rolayne S.

    1983-01-01

    Analyzed the complete interaction of high and low consensus groups in a basic small group course. Interaction analysis indicated that both the relational and content levels of communication are significantly different for high versus low consensus groups. The conclusion that increased feedback leads to decision satisfaction was confirmed. (JAC)

  5. Innovation management and marketing in the high-tech sector: A content analysis of advertisements

    DEFF Research Database (Denmark)

    Gerhard, D.; Brem, Alexander; Baccarella, Ch.

    2011-01-01

    Advertizing high-technology products is a tricky and critical task for every company, since it means operating in an environment with high market uncertainty. The work presents results of a content analysis of 110 adverts for consumer electronics products which examines how these products and the...

  6. Dissolution of cellulose in ionic liquid: A review

    Science.gov (United States)

    Mohd, N.; Draman, S. F. S.; Salleh, M. S. N.; Yusof, N. B.

    2017-02-01

    Dissolution of cellulose with ionic liquids (IL) and deep eutectic solvent (DES) lets the comprehensive dissolution of cellulose. Basically, cellulose can be dissolved, in some hydrophilic ionic liquids, such as 1-butyl-3-methylimidazolium chloride (BMIMCl) and 1-allyl-3-methylimidazolium chloride (AMIMCl). Chloride based ionic liquids are suitable solvents for cellulose dissolution. Although the ILs is very useful in fine chemical industry, its application in the pharmaceutical and food industry have been very limited due to issues with toxicity, purity, and high cost. Seeing to these limitations, new green alternative solvent which is DES was used. This green solvents, may be definitely treated as the next-generation reagents for more sustainable industrial development. Thus, this review aims to discuss the dissolution of cellulose either with ionic liquids or DES and its application.

  7. In-situ glyoxalization during biosynthesis of bacterial cellulose.

    Science.gov (United States)

    Castro, Cristina; Cordeiro, Nereida; Faria, Marisa; Zuluaga, Robin; Putaux, Jean-Luc; Filpponen, Ilari; Velez, Lina; Rojas, Orlando J; Gañán, Piedad

    2015-08-01

    A novel method to synthesize highly crosslinked bacterial cellulose (BC) is reported. The glyoxalization is started in-situ, in the culture medium during biosynthesis of cellulose by Gluconacetobacter medellensis bacteria. Strong crosslinked networks were formed in the contact areas between extruded cellulose ribbons by reaction with the glyoxal precursors. The crystalline structure of cellulose was preserved while the acidic component of the surface energy was reduced. As a consequence, its predominant acidic character and the relative contribution of the dispersive component increased, endowing the BC network with a higher hydrophobicity. This route for in-situ crosslinking is expected to facilitate other modifications upon biosynthesis of cellulose ribbons by microorganisms and to engineer the strength and surface energy of their networks.

  8. The Solubility of Natural Cellulose After DBD Plasma Treatment

    Institute of Scientific and Technical Information of China (English)

    WU Jun; ZENG Fengcai; CHEN Bingqiang

    2008-01-01

    Natural cellulose was treated by an atmospheric DBD plasma. The solubility of cel-lulose in a diluted alkaline solution after the plasma treatment was investigated. The properties were characterized by X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spec-troscopy (FTIR) and scanning electron microscopy (SEM). The results indicated that the surface of cellulose treated by the argon DBD plasma was significantly etched, and the relevant force of hy-drogen bonding was decreased. This might be the essential reason for the solubility improvement of natural cellulose in the diluted alkaline solution. Through a comparison of two discharge modes, the atmospheric DBD plasma gun and the parallel plate capacitively coupled DBD plasma, it wasfound that the atmospheric DBD plasma gun was more effective in fragmentizing the cellulose due to its production of a high energy plasma based on its special structure [6] .

  9. Overview of Cellulose Nanomaterials, Their Capabilities and Applications

    Science.gov (United States)

    Moon, Robert J.; Schueneman, Gregory T.; Simonsen, John

    2016-09-01

    Cellulose nanomaterials (CNs) are a new class of cellulose particles with properties and functionalities distinct from molecular cellulose and wood pulp, and as a result, they are being developed for applications that were once thought impossible for cellulosic materials. Momentum is growing in CN research and development, and commercialization in this field is happening because of the unique combination of characteristics (e.g., high mechanical properties, sustainability, and large-scale production potential) and utility across a broad spectrum of material applications (e.g. as an additive, self-sustaining structures, and template structures) that CNs offer. Despite the challenges typical for materials development, CN and near-CN production is ramping up with pilot scale to industry demonstration trials, and the first commercial products are starting to hit the marketplace. This review provides a broad overview of CNs and their capabilities that are enabling new application areas for cellulose-based materials.

  10. Cellulose-reinforced composites: from micro-to nanoscale

    Directory of Open Access Journals (Sweden)

    Alain Dufresne

    2013-01-01

    Full Text Available This paper present the most relevant advances in the fields of: i cellulose fibres surface modification; ii cellulose fibres-based composite materials; and iii nanocomposites based on cellulose whiskers or starch platelet-like nanoparticles. The real breakthroughs achieved in the first topic concern the use of solvent-free grafting process (plasma and the grafting of the matrix at the surface of cellulose fibres through isocyanate-mediated grafting or thanks to "click chemistry". Concerning the second topic, it is worth to mention that for some cellulose/matrix combination and in the presence of adequate aids or specific surface treatment, high performance composite materials could be obtained. Finally, nanocomposites allow using the semi-crystalline nature and hierarchical structure of lignocellulosic fibres and starch granules to more deeply achieve this goal profitably exploited by Mother Nature

  11. Evaluation of Compatibility of ToxCast High-Throughput/High-Content Screening Assays with Engineered Nanomaterials

    Science.gov (United States)

    High-throughput and high-content screens are attractive approaches for prioritizing nanomaterial hazards and informing targeted testing due to the impracticality of using traditional toxicological testing on the large numbers and varieties of nanomaterials. The ToxCast program a...

  12. Effects of cellulose whiskers on properties of soy protein thermoplastics.

    Science.gov (United States)

    Wang, Yixiang; Cao, Xiaodong; Zhang, Lina

    2006-07-14

    Environmentally-friendly SPI/cellulose whisker composites were successfully prepared using a colloidal suspension of cellulose whiskers, to reinforce soy protein isolate (SPI) plastics. The cellulose whiskers, having an average length of 1.2 microm and diameter of 90 nm, respectively, were prepared from cotton linter pulp by hydrolyzing with sulfuric acid aqueous solution. The effects of the whisker content on the morphology and properties of the glycerol-plasticized SPI composites were investigated by scanning electron microscopy, dynamic mechanical thermal analysis, differential scanning calorimetry, ultraviolet-visible spectroscopy, water-resistivity testing and tensile testing. The results indicated that, with the addition of 0 to 30 wt.-% of cellulose whiskers, strong interactions occurred both between the whiskers and between the filler and the SPI matrix, reinforcing the composites and preserving their biodegradability. Both the tensile strength and Young's modulus of the SPI/cellulose whisker composites increased from 5.8 to 8.1 MPa and from 44.7 to 133.2 MPa, respectively, at a relative humidity of 43%, following an increase of the whisker content from 0 to 30 wt.-%. Furthermore, the incorporation of the cellulose whiskers into the SPI matrix led to an improvement in the water resistance for the SPI-based composites.

  13. Effect of Nitrification Condition and Cellulose Prereatment on Nitrogen Content and Its Distribution Uniformity of Nitrocellulose%硝化工艺及原料的预处理对硝化棉含氮量及其分布均匀性的影响

    Institute of Scientific and Technical Information of China (English)

    王文後; 邵自强; 左洋; 李永红; 冯蕾; 王飞後

    2011-01-01

    采用硝化棉(NC)含氮量及其分布均匀性测试仪,考察了硝化系数、精制棉的膨润预处理和超声预处理三因素对硝化棉含氮量及氮量分布均匀性的影响规律.结果表明,NC的含氮量随硝化系数的增大而增大.当硝化系数分别为40、50和80时,NC含氮量分布值Dε较小,当硝化系数为20或100时,Dε值均显著增大;采用硫脲和尿素水溶液预处理精制棉,对NC的含氮量没有影响,但可使NC的氮量分布变窄;随着精制棉超声处理时间的延长,NC的含氮量逐渐增大.当超声波处理时间分别为10和30 min时,NC的含氮量分布明显变宽,NC的相对分子质量降低.当处理时间为60 min时,NC的氮量分布与未处理前相比略微变窄,NC的相对分子质量略有增大.%The effect of three factors involving nitrification coefficient, swelling and ultrosonic pretreatment of cellulose on the nitrogen content and its distribution uniformity of nitrocellulose were investigated by a testing instrument for nitrogen content and distribution uniformity of NC. The results show that the nitrogen content of NC increased with increasing nitrification coefficient; the nitrogen distribution value Dε were low when the nitrification coefficient was 40,50 and 80, while it significantly increased at 20 or 100; Swelling pretreatment of cotton cellulose via thiou-rea and urea aqueous solution did not affect the nitrogen content of NC, but it can narrow NC's nitrogen distribution; prolonging the ultrasonic treatment time of cotton cellulose within the studing scale resulted in an increase of nitrogen content of NC. The nitrogen distribution of NC became significantly wider and the moleculor weight decreased after 10min or 30 min ultrasonic treatment, while the nitrogen distribution became slightly narrower comparing with that of untreatment when ultrasonic treatment time prolonged to 60min, and the molecular weight increased slightly.

  14. Microwave Pretreatment For Hydrolysis Of Cellulose

    Science.gov (United States)

    Cullingford, Hatice S.; George, Clifford E.; Lightsey, George R.

    1993-01-01

    Microwave pretreatment enhances enzymatic hydrolysis of cellulosic wastes into soluble saccharides used as feedstocks for foods, fuels, and other products. Low consumption of energy, high yield, and low risk of proposed hydrolysis process incorporating microwave pretreatment makes process viable alternative to composting.

  15. Nanofibrous microfiltration membrane based on cellulose nanowhiskers.

    Science.gov (United States)

    Ma, Hongyang; Burger, Christian; Hsiao, Benjamin S; Chu, Benjamin

    2012-01-09

    A multilayered nanofibrous microfiltration (MF) membrane system with high flux, low pressure drop, and high retention capability against both bacteria and bacteriophages (a virus model) was developed by impregnating ultrafine cellulose nanowhiskers (diameter about 5 nm) into an electrospun polyacrylonitrile (PAN) nanofibrous scaffold (fiber diameter about 150 nm) supported by a poly(ethylene terephthalate) (PET) nonwoven substrate (fiber diameter about 20 μm). The cellulose nanowhiskers were anchored on the PAN nanofiber surface, forming a cross-linked nanostructured mesh with very high surface-to-volume ratio and a negatively charged surface. The mean pore size and pore size distribution of this MF system could be adjusted by the loading of cellulose nanowhiskers, where the resulting membrane not only possessed good mechanical properties but also high surface charge density confirmed by the conductivity titration and zeta potential measurements. The results indicated that a test cellulose nanowhisker-based MF membrane exhibited 16 times higher adsorption capacity against a positively charged dye over a commercial nitrocellulose-based MF membrane. This experimental membrane also showed full retention capability against bacteria, for example, E. coli and B. diminuta (log reduction value (LRV) larger than 6) and decent retention against bacteriophage MS2 (LRV larger than 2).

  16. Atomic force microscopy characterization of cellulose nanocrystals

    Science.gov (United States)

    Roya R. Lahiji; Xin Xu; Ronald Reifenberger; Arvind Raman; Alan Rudie; Robert J. Moon

    2010-01-01

    Cellulose nanocrystals (CNCs) are gaining interest as a “green” nanomaterial with superior mechanical and chemical properties for high-performance nanocomposite materials; however, there is a lack of accurate material property characterization of individual CNCs. Here, a detailed study of the topography, elastic and adhesive properties of individual wood-derived CNCs...

  17. Biomass Supply Chain and Conversion Economics of Cellulosic Ethanol

    Science.gov (United States)

    Gonzalez, Ronalds W.

    2011-12-01

    Cellulosic biomass is a potential and competitive source for bioenergy production, reasons for such acclamation include: biomass is one the few energy sources that can actually be utilized to produce several types of energy (motor fuel, electricity, heat) and cellulosic biomass is renewable and relatively found everywhere. Despite these positive advantages, issues regarding cellulosic biomass availability, supply chain, conversion process and economics need a more comprehensive understanding in order to identify the near short term routes in biomass to bioenergy production. Cellulosic biomass accounts for around 35% to 45% of cost share in cellulosic ethanol production, in addition, different feedstock have very different production rate, (dry ton/acre/year), availability across the year, and chemical composition that affect process yield and conversion costs as well. In the other hand, existing and brand new conversion technologies for cellulosic ethanol production offer different advantages, risks and financial returns. Ethanol yield, financial returns, delivered cost and supply chain logistic for combinations of feedstock and conversion technology are investigated in six studies. In the first study, biomass productivity, supply chain and delivered cost of fast growing Eucalyptus is simulated in economic and supply chain models to supply a hypothetic ethanol biorefinery. Finding suggests that Eucalyptus can be a potential hardwood grown specifically for energy. Delivered cost is highly sensitive to biomass productivity, percentage of covered area. Evaluated at different financial expectations, delivered cost can be competitive compared to current forest feedstock supply. In the second study, Eucalyptus biomass conversion into cellulosic ethanol is simulated in the dilute acid pretreatment, analysis of conversion costs, cost share, CAPEX and ethanol yield are examined. In the third study, biomass supply and delivered cost of loblolly pine is simulated in economic

  18. Synthesis and properties of fluorescent cotton cellulose labeled with norfloxacin

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    To expand the application of cellulose in the field of fluorescence techniques, the cotton cellulose was labeled with norfloxacin (Cell-NF) via a three-step reaction, involving alkali treatment, epoxy activation, and opening of the epoxy rings with norfloxacin molecules. And the coordination complexes of Cell-NF with rare earth ions terbium (Cell-NF-Tb) and europium (Cell-NF-Eu) were obtained. The products were detected by IR, TG, XPS, UV and fluorescence spectra. Results showed that the norfloxacin content of the labeled cellulose was about 6.73 w‰ and the start temperature of decomposition of the Cell-NF was raised by 40°C compared with the stock cotton cellulose. When excited at 340 nm, the Cell-NF, Cell-NF-Tb, and Cell-NF-Eu in the solid state could emit violet (430 nm), green (549 nm) and red (620 nm) light, respectively.

  19. Synthesis and characterization of novel cellulose ether sulfates.

    Science.gov (United States)

    Rohowsky, Juta; Heise, Katja; Fischer, Steffen; Hettrich, Kay

    2016-05-20

    The synthesis and characterization of novel cellulose sulfate derivatives was reported. Various cellulose ethers were prepared in a homogeneous reaction with common sulfating agents. The received product possess different properties in dependence on the reaction conditions like sulfating agent, solvent, reaction time and reaction temperature. The cellulose ether sulfates are all soluble in water, they rheological behavior could be determined by viscosity measurements and the determination of the sulfur content by elemental analysis lead to a resulting degree of substitution ascribed to sulfate groups (DSSul) of the product. A wide range of products from DSSul 0.1 to DSSul 2.7 will be obtained. Furthermore the cellulose sulfate ethers could be characterized by Raman spectroscopy.

  20. Stone Matrix Asphalt (SMA is a gap-graded mix that is gaining popularity worldwide. Generally, gap graded mixes are thought to be weak in fatigue resistance. In this study, cellulose fibers were pre-blended in PG64-22 binder with fiber proportions of 0.2%, 0.4%, 0.6%, 0.8% and 1.0% by weight of aggregates. The fiber-modified binder showed improved rheological properties and showed that the PG64-22 binder can be modified and raised to PG70-22 grade. The cellulose oil palm fiber (COPF was found to improve the diameteral fatigue performance of SMA design mix. The fatigue life increased to a maximum at a fiber content of about 0.6%, whilst the tensile stress and stiffness also showed a similar trend in performance. The initial strains of the mix were lowest at a fiber content of 0.6%.

    Directory of Open Access Journals (Sweden)

    Ratnasamy Muniandy

    2006-01-01

    Full Text Available Stone Matrix Asphalt (SMA is a gap-graded mix that is gaining popularity worldwide. Generally, gap graded mixes are thought to be weak in fatigue resistance. In this study, cellulose fibers were pre-blended in PG64-22 binder with fiber proportions of 0.2%, 0.4%, 0.6%, 0.8% and 1.0% by weight of aggregates. The fiber-modified binder showed improved rheological properties and showed that the PG64-22 binder can be modified and raised to PG70-22 grade. The cellulose oil palm fiber (COPF was found to improve the diameteral fatigue performance of SMA design mix. The fatigue life increased to a maximum at a fiber content of about 0.6%, whilst the tensile stress and stiffness also showed a similar trend in performance. The initial strains of the mix were lowest at a fiber content of 0.6%.

  1. Calculation Method to Determine the Group Composition of Vacuum Distillate with High Content of Saturated Hydrocarbons

    Directory of Open Access Journals (Sweden)

    Nazarova Galina

    2016-01-01

    Full Text Available Calculation method to determine the group composition of the heavy fraction of vacuum distillate with high content of saturated hydrocarbons, obtained by vacuum distillation of the residue from the West Siberian oil with subsequent hydrotreating, are given in this research. The method is built on the basis of calculation the physico-chemical characteristics and the group composition of vacuum distillate according to the fractional composition and density considering with high content of saturated hydrocarbons in the fraction. Calculation method allows to determine the content of paraffinic, naphthenic, aromatic hydrocarbons and the resins in vacuum distillate with high accuracy and can be used in refineries for rapid determination of the group composition of vacuum distillate.

  2. Graph cut and image intensity-based splitting improves nuclei segmentation in high-content screening

    Science.gov (United States)

    Farhan, Muhammad; Ruusuvuori, Pekka; Emmenlauer, Mario; Rämö, Pauli; Yli-Harja, Olli; Dehio, Christoph

    2013-02-01

    Quantification of phenotypes in high-content screening experiments depends on the accuracy of single cell analysis. In such analysis workflows, cell nuclei segmentation is typically the first step and is followed by cell body segmentation, feature extraction, and subsequent data analysis workflows. Therefore, it is of utmost importance that the first steps of high-content analysis are done accurately in order to guarantee correctness of the final analysis results. In this paper, we present a novel cell nuclei image segmentation framework which exploits robustness of graph cut to obtain initial segmentation for image intensity-based clump splitting method to deliver the accurate overall segmentation. By using quantitative benchmarks and qualitative comparison with real images from high-content screening experiments with complicated multinucleate cells, we show that our method outperforms other state-of-the-art nuclei segmentation methods. Moreover, we provide a modular and easy-to-use implementation of the method for a widely used platform.

  3. Optimization of the Content of Tricalcium Silicate of High Cementing Clinker

    Institute of Scientific and Technical Information of China (English)

    CHEN Lin; SHEN Xiaodong; MA Suhua; HUANG Yeping; ZHONG Baiqian

    2011-01-01

    Optimization of the content of tricalcium silicate (C3S) of high cementing clinker was investigated. The content of free-CaO(f-CaO), mineral composite, the content of C3S in the clinker and the hydration product were analyzed by chemical analysis and X-ray diffraction (XRD). "K Value" method of QXRD was selected as a quantitative analysis way to measure the content of C3S, and the strength of cement paste was determined. The results show that at a water cement ratio of 0.29, the strength of cement paste with 73% C3S can be up to 97.5 MPa at 28 days age. The strength at 28 d of cement with 73% C3S is 16% higher than that with 78% C3S at water requirement for normal consistency. The relationship between the strength of high cementing Portland cement and the content of C3S in the clinker is nonlinear. According to the strength of cement paste, the optimal content of C3S in cement clinker is around 73% in this paper.

  4. Decreased adipose tissue zinc content is associated with metabolic parameters in high fat fed Wistar rats

    Directory of Open Access Journals (Sweden)

    Alexey A. Tinkov

    2016-03-01

    Full Text Available Background. Limited data on adipose tissue zinc content in obesity exist. At the same time, the association between adipose tissue zinc content and metabolic parameters in dietary-induced obesity is poorly studied. Therefore, the primary objective of this study is to assess adipose tissue zinc content and its association  with morphometric parameters, adipokine spectrum, proinflammatory cytokines, and apolipoprotein profile in high fat fed Wistar rats. Material and methods. A total of 48 adult female Wistar rats were used in the present study. Rats were fed either control (10% of fat or high fat diet (31.6% of fat. Adipose tissue zinc content was assessed using inductively coupled plasma mass spectrometry. Rats’ serum was examined for adiponectin, leptin, insulin, interleukin-6, and tumor necrosis factor-α using enzyme-linked immunosorbent assay kits. Serum glucose and apolipoprotein spectrum were also evaluated. Results. High fat feeding resulted in a significant 34% decrease in adipose tissue zinc content in comparison to the control values. Fat pad zinc levels were significantly inversely associated with morphometric param- eters, circulating leptin, insulin, tumor necrosis factor-α levels and HOMA-IR values. At the same time,      a significant correlation with apolipoprotein A1 concentration was observed. Conclusion. Generally, the obtained data indicate that (1 high fat feeding results in decreased adipose tis- sue zinc content; (2 adipose tissue zinc content is tightly associated with excessive adiposity, inflammation, insulin resistance and potentially atherogenic changes.

  5. Magnetic and mechanical properties of FeSi alloys with high Si content

    Institute of Scientific and Technical Information of China (English)

    LU Feng-shuang; QIAO Liang; BI Xiao-fang

    2006-01-01

    The chemical vapor(CVD) deposition-diffusion method was applied to prepare FeSi alloys with high silicon content up to 6.5%. In spite of various deposition and post-annealing, the sample remains α-Fe bcc structure. The cross section of the composition was analyzed to evaluate the Si content and distribution before and after annealing. The results show that the soft magnetic properties are improved by increasing the silicon content. For the samples containing about 6.5% Si, the coercivity decreases to 60 from 237.3 A/m of the original. It is also obtained that, in addition to the Si content, Si distribution has a large influence on the core loss due to the effect of resistivity. The micro-hardnesses were also evaluated along the cross-section after various annealings.

  6. Simple green approach to reinforce natural rubber with bacterial cellulose nanofibers.

    Science.gov (United States)

    Trovatti, Eliane; Carvalho, Antonio J F; Ribeiro, Sidney J L; Gandini, Alessandro

    2013-08-12

    Natural rubber (NR) is a renewable polymer with a wide range of applications, which is constantly tailored, further increasing its utilizations. The tensile strength is one of its most important properties susceptible of being enhanced by the simple incorporation of nanofibers. The preparation and characterization of natural-rubber based nanocomposites reinforced with bacterial cellulose (BC) and bacterial cellulose coated with polystyrene (BCPS), yielded high performance materials. The nanocomposites were prepared by a simple and green process, and characterized by tensile tests, dynamical mechanical analysis (DMA), scanning electron microscopy (SEM), and swelling experiments. The effect of the nanofiber content on morphology, static, and dynamic mechanical properties was also investigated. The results showed an increase in the mechanical properties, such as Young's modulus and tensile strength, even with modest nanofiber loadings.

  7. High-content single-cell analysis on-chip using a laser microarray scanner.

    Science.gov (United States)

    Zhou, Jing; Wu, Yu; Lee, Sang-Kwon; Fan, Rong

    2012-12-07

    High-content cellomic analysis is a powerful tool for rapid screening of cellular responses to extracellular cues and examination of intracellular signal transduction pathways at the single-cell level. In conjunction with microfluidics technology that provides unique advantages in sample processing and precise control of fluid delivery, it holds great potential to transform lab-on-a-chip systems for high-throughput cellular analysis. However, high-content imaging instruments are expensive, sophisticated, and not readily accessible. Herein, we report on a laser scanning cytometry approach that exploits a bench-top microarray scanner as an end-point reader to perform rapid and automated fluorescence imaging of cells cultured on a chip. Using high-content imaging analysis algorithms, we demonstrated multiplexed measurements of morphometric and proteomic parameters from all single cells. Our approach shows the improvement of both sensitivity and dynamic range by two orders of magnitude as compared to conventional epifluorescence microscopy. We applied this technology to high-throughput analysis of mesenchymal stem cells on an extracellular matrix protein array and characterization of heterotypic cell populations. This work demonstrates the feasibility of a laser microarray scanner for high-content cellomic analysis and opens up new opportunities to conduct informative cellular analysis and cell-based screening in the lab-on-a-chip systems.

  8. Nanomanufacturing metrology for cellulosic nanomaterials: an update

    Science.gov (United States)

    Postek, Michael T.

    2014-08-01

    The development of the metrology and standards for advanced manufacturing of cellulosic nanomaterials (or basically, wood-based nanotechnology) is imperative to the success of this rising economic sector. Wood-based nanotechnology is a revolutionary technology that will create new jobs and strengthen America's forest-based economy through industrial development and expansion. It allows this, previously perceived, low-tech industry to leap-frog directly into high-tech products and processes and thus improves its current economic slump. Recent global investments in nanotechnology programs have led to a deeper appreciation of the high performance nature of cellulose nanomaterials. Cellulose, manufactured to the smallest possible-size ( 2 nm x 100 nm), is a high-value material that enables products to be lighter and stronger; have less embodied energy; utilize no catalysts in the manufacturing, are biologically compatible and, come from a readily renewable resource. In addition to the potential for a dramatic impact on the national economy - estimated to be as much as $250 billion worldwide by 2020 - cellulose-based nanotechnology creates a pathway for expanded and new markets utilizing these renewable materials. The installed capacity associated with the US pulp and paper industry represents an opportunity, with investment, to rapidly move to large scale production of nano-based materials. However, effective imaging, characterization and fundamental measurement science for process control and characterization are lacking at the present time. This talk will discuss some of these needed measurements and potential solutions.

  9. Enzymatic Hydrolysis of biomasses having a high dry matter (DM) content

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to a process for liquefaction and saccharification of polysaccharide containing biomasses, having a relatively high dry matter content. The present invention combines enzymatic hydrolysis with a type of mixing relying on the principle of gravity ensuring that the bio......The present invention relates to a process for liquefaction and saccharification of polysaccharide containing biomasses, having a relatively high dry matter content. The present invention combines enzymatic hydrolysis with a type of mixing relying on the principle of gravity ensuring...

  10. Enhanced enzymatic hydrolysis of cellulose in microgels.

    Science.gov (United States)

    Chang, Aiping; Wu, Qingshi; Xu, Wenting; Xie, Jianda; Wu, Weitai

    2015-07-04

    A cellulose-based microgel, where an individual microgel contains approximately one cellulose chain on average, is synthesized via free radical polymerization of a difunctional small-molecule N,N'-methylenebisacrylamide in cellulose solution. This microgelation leads to a low-ordered cellulose, favoring enzymatic hydrolysis of cellulose to generate glucose.

  11. Multi Feature Content Based Video Retrieval Using High Level Semantic Concept

    Directory of Open Access Journals (Sweden)

    Hamdy K. Elminir

    2012-07-01

    Full Text Available Content-based retrieval allows finding information by searching its content rather than its attributes. The challenge facing content-based video retrieval (CBVR is to design systems that can accurately and automatically process large amounts of heterogeneous videos. Moreover, content-based video retrieval system requires in its first stage to segment the video stream into separate shots. Afterwards features are extracted for video shots representation. And finally, choose a similarity/distance metric and an algorithm that is efficient enough to retrieve query - related videos results. There are two main issues in this process; the first is how to determine the best way for video segmentation and key frame selection. The second is the features used for video representation. Various features can be extracted for this sake including either low or high level features. A key issue is how to bridge the gap between low and high level features. This paper proposes a system for a content based video retrieval system that tries to address the aforementioned issues by using adaptive threshold for video segmentation and key frame selection as well as using both low level features together with high level semantic object annotation for video representation. Experimental results show that the use of multi features increases both precision and recall rates by about 13% to 19 % than traditional system that uses only color feature for video retrieval.

  12. Innovation management and marketing in the high-tech sector: A content analysis of advertisements

    DEFF Research Database (Denmark)

    Gerhard, D.; Brem, Alexander; Baccarella, Ch.

    2011-01-01

    Advertizing high-technology products is a tricky and critical task for every company, since it means operating in an environment with high market uncertainty. The work presents results of a content analysis of 110 adverts for consumer electronics products which examines how these products...... and the incorporated technology are communicated to the customer. Based on established coding schemes, the content and the appeals of the adverts are evaluated by coders. The results show that these adverts are very informative, mainly have rational appeals and feature products being in the early stage of their life...... cycles. Regarding the specific content, the ‘mother brand’ is shown to play a very important role. On the other hand, the results show that incorporated technology, its superiority and functionality do not play an important role in the advertisements...

  13. HIGH MOLECULAR CELLULOSE ESTERS. MECHANISM OF ACTION IN SUSTAINED RELEASE MATRIX TABLETS. DISSOLUTION PROFILE OF ACTIVE DRUG DEPENDING ON MOLECULAR WEIGHT AND HYDROPHILIC PROPERTIES OF POLYMERS

    Directory of Open Access Journals (Sweden)

    S. V. Trofimov

    2015-01-01

    Full Text Available This article reviews cellulose esters as important excipients in development of dosage forms with sustained release. We have studied modern methods of drug development, based on technological, and physical and chemical properties of excipients to provide a sustained release effect and the mechanism of interaction between active substance and excipients for justification of choice of the optimum prolonging agent in compliance with desirable result. Different cellulose esters were used as model excipients. They were hydroxypropylmethylcellulose (HPMC and hydroxyethylcellulose (HEC. we have studied an effect of molecular weight and hydrophilic properties on dissolution rate of active substance from the tablets with sustained release.

  14. A comparative study on properties of micro and nanopapers produced from cellulose and cellulose nanofibres.

    Science.gov (United States)

    Mtibe, A; Linganiso, Linda Z; Mathew, Aji P; Oksman, K; John, Maya J; Anandjiwala, Rajesh D

    2015-03-15

    Cellulose nanocrystals (CNCs) and cellulose nanofibres (CNFs) were successfully extracted from cellulose obtained from maize stalk residues. A variety of techniques, such as Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were used for characterization and the experimental results showed that lignin and hemicellulose were removed to a greater extent by following the chemical methods. Atomic force microscopy (AFM) results confirmed that the diameters of CNCs and CNFs were ranging from 3 to 7 nm and 4 to 10nm, respectively, with their lengths in micro scale. CNCs suspension showed a flow of birefringence, however, the same was not observed in the case of suspension containing CNFs. XRD analysis confirmed that CNCs had high crystallinity index in comparison to cellulose and CNFs. Nanopapers were prepared from CNCs and CNFs by solvent evaporation method. Micropapers were also prepared from cellulose pulp by the same technique. Nanopapers made from CNFs showed less transparency as compared to nanopapers produced from CNCs whereas high transparency as compared to micropaper. Nanopapers produced from CNFs provided superior mechanical properties as compared to both micropaper and nanopapers produced from CNCs. Also, nanopapers produced from CNFs were thermally more stable as compared to nanopapers produced from CNCs but thermally less stable as compared to micropapers.

  15. SPECIFIC INTERACTION ACTING AT A CELLULOSE-BINDING DOMAIN/CELLULOSE INTERFACE FOR PAPERMAKING APPLICATION

    Directory of Open Access Journals (Sweden)

    Shingo Yokota

    2008-11-01

    Full Text Available Specific and strong cellulose-binding characteristics were utilized for promoting retention of additives in contaminated papermaking systems. Cellulose-binding domain (CBD of cellulase derived from Trichoderma viride was separated by digestion with papain, and then introduced into anionic polyacrylamide (A-PAM through a condensation reaction using water-soluble carbodiimide. The CBD-modified A-PAM (CBD-A-PAM showed good retention on pulp fibers, resulting in high tensile strength paper sheets. The effect remained almost unchanged in the presence of model interfering substances such as ligninsulfonate and Ca2+ ions, whereas commercial cationic paper-strengthening polymer became ineffective. The cellulose-binding force of CBD was quantitatively determined by atomic force microscopy (AFM in the liquid state. Histidine-tagged CBD protein was obtained using Escherichia coli via an expression of CBD derived from Cellulomonas fimi, and immobilized on a gold-coated AFM probe. A strong attractive force was detected only at a CBD/cellulose interface, even when Ca2+ ions were present in high concentration. Direct estimation of CBD affinity for cellulose substrate by AFM would provide significant information on the interfacial interactions useful for the functional design of papermaking additives.

  16. Multiphase materials with lignin. VI. Effect of cellulose derivative structure on blend morphology with lignin

    Science.gov (United States)

    Timothy G. Rials; Wolfgang G. Glasser

    1989-01-01

    Polymeric blends of lignin with ethyl cellulose (EC) and cellulose acetate/butyrate (CAB) prepared by solution casting from dioxane. Fracture surface analysis by scanning electron microscopy revealed phase separation when the lignin content exceeded 10% for blends with EC and 5% in the CAB system. While this phase behavior is as predicted for the EC blends, a greater...

  17. Thin blend films of cellulose and polyacrylonitrile

    Science.gov (United States)

    Lu, Rui; Zhang, Xin; Mao, Yimin; Briber, Robert; Wang, Howard

    Cellulose is the most abundant renewable, biocompatible and biodegradable natural polymer. Cellulose exhibits excellent chemical and mechanical stability, which makes it useful for applications such as construction, filtration, bio-scaffolding and packaging. To further expand the potential applications of cellulose materials, their alloying with synthetic polymers has been investigated. In this study, thin films of cotton linter cellulose (CLC) and polyacrylonitrile (PAN) blends with various compositions spanning the entire range from neat CLC to neat PAN were spun cast on silicon wafers from common solutions in dimethyl sulfoxide / ionic liquid mixtures. The morphologies of thin films were characterized using optical microscopy, atomic force microscopy, scanning electron microscopy and X-ray reflectivity. Morphologies of as-cast films are highly sensitive to the film preparation conditions; they vary from featureless smooth films to self-organized ordered nano-patterns to hierarchical structures spanning over multiple length scales from nanometers to tens of microns. By selectively removing the PAN-rich phase, the structures of blend films were studied to gain insights in their very high stability in hot water, acid and salt solutions.

  18. Evolution of High Cellulolytic Activity in Symbiotic Streptomyces through Selection of Expanded Gene Content and Coordinated Gene Expression.

    Directory of Open Access Journals (Sweden)

    Adam J Book

    2016-06-01

    Full Text Available The evolution of cellulose degradation was a defining event in the history of life. Without efficient decomposition and recycling, dead plant biomass would quickly accumulate and become inaccessible to terrestrial food webs and the global carbon cycle. On land, the primary drivers of plant biomass deconstruction are fungi and bacteria in the soil or associated with herbivorous eukaryotes. While the ecological importance of plant-decomposing microbes is well established, little is known about the distribution or evolution of cellulolytic activity in any bacterial genus. Here we show that in Streptomyces, a genus of Actinobacteria abundant in soil and symbiotic niches, the ability to rapidly degrade cellulose is largely restricted to two clades of host-associated strains and is not a conserved characteristic of the Streptomyces genus or host-associated strains. Our comparative genomics identify that while plant biomass degrading genes (CAZy are widespread in Streptomyces, key enzyme families are enriched in highly cellulolytic strains. Transcriptomic analyses demonstrate that cellulolytic strains express a suite of multi-domain CAZy enzymes that are coregulated by the CebR transcriptional regulator. Using targeted gene deletions, we verify the importance of a highly expressed cellulase (GH6 family cellobiohydrolase and the CebR transcriptional repressor to the cellulolytic phenotype. Evolutionary analyses identify complex genomic modifications that drive plant biomass deconstruction in Streptomyces, including acquisition and selective retention of CAZy genes and transcriptional regulators. Our results suggest that host-associated niches have selected some symbiotic Streptomyces for increased cellulose degrading activity and that symbiotic bacteria are a rich biochemical and enzymatic resource for biotechnology.

  19. Evolution of High Cellulolytic Activity in Symbiotic Streptomyces through Selection of Expanded Gene Content and Coordinated Gene Expression.

    Science.gov (United States)

    Book, Adam J; Lewin, Gina R; McDonald, Bradon R; Takasuka, Taichi E; Wendt-Pienkowski, Evelyn; Doering, Drew T; Suh, Steven; Raffa, Kenneth F; Fox, Brian G; Currie, Cameron R

    2016-06-01

    The evolution of cellulose degradation was a defining event in the history of life. Without efficient decomposition and recycling, dead plant biomass would quickly accumulate and become inaccessible to terrestrial food webs and the global carbon cycle. On land, the primary drivers of plant biomass deconstruction are fungi and bacteria in the soil or associated with herbivorous eukaryotes. While the ecological importance of plant-decomposing microbes is well established, little is known about the distribution or evolution of cellulolytic activity in any bacterial genus. Here we show that in Streptomyces, a genus of Actinobacteria abundant in soil and symbiotic niches, the ability to rapidly degrade cellulose is largely restricted to two clades of host-associated strains and is not a conserved characteristic of the Streptomyces genus or host-associated strains. Our comparative genomics identify that while plant biomass degrading genes (CAZy) are widespread in Streptomyces, key enzyme families are enriched in highly cellulolytic strains. Transcriptomic analyses demonstrate that cellulolytic strains express a suite of multi-domain CAZy enzymes that are coregulated by the CebR transcriptional regulator. Using targeted gene deletions, we verify the importance of a highly expressed cellulase (GH6 family cellobiohydrolase) and the CebR transcriptional repressor to the cellulolytic phenotype. Evolutionary analyses identify complex genomic modifications that drive plant biomass deconstruction in Streptomyces, including acquisition and selective retention of CAZy genes and transcriptional regulators. Our results suggest that host-associated niches have selected some symbiotic Streptomyces for increased cellulose degrading activity and that symbiotic bacteria are a rich biochemical and enzymatic resource for biotechnology.

  20. Ethanol production from food waste at high solid contents with vacuum recovery technology

    Science.gov (United States)

    Ethanol production from food wastes does not only solve the environmental issues but also provide renewable biofuel to partially substitute fossil fuels. This study investigated the feasibility of utilization of food wastes for producing ethanol at high solid contents (35%, w/w). Vacuum recovery sys...

  1. Cultural Parallax and Content Analysis: Images of Black Women in High School History Textbooks

    Science.gov (United States)

    Woyshner, Christine; Schocker, Jessica B.

    2015-01-01

    This study investigates the representation of Black women in high school history textbooks. To examine the extent to which Black women are represented visually and to explore how they are portrayed, the authors use a mixed-methods approach that draws on analytical techniques in content analysis and from visual culture studies. Their findings…

  2. Exceptional heat stability of high protein content dispersions containing whey protein particles

    NARCIS (Netherlands)

    Saglam, D.; Venema, P.; Vries, de R.J.; Linden, van der E.

    2014-01-01

    Due to aggregation and/or gelation during thermal treatment, the amount of whey proteins that can be used in the formulation of high protein foods e.g. protein drinks, is limited. The aim of this study was to replace whey proteins with whey protein particles to increase the total protein content and

  3. The content and role of formal contracts in high-tech alliances

    NARCIS (Netherlands)

    Jong, G. de; Klein Woolthuis, R.J.A.

    2009-01-01

    In this study we investigate the governance structure of innovation processes in high-tech alliances, focusing on the content and role of formal contracts. The design of a formal agreement is one of the most important strategic decisions for alliance partners. Drawing upon transaction cost arguments

  4. [Determination of high content of tin in geochemical samples by solid emission spectrometry].

    Science.gov (United States)

    Yao, Jian-Zhen; Hao, Zhi-Hong; Tang, Rui-Ling; Li, Xiao-Jing; Li, Wen-Ge; Zhang, Qin

    2013-11-01

    A method for the determination of high content of tin in geochemical samples by solid emission spectrometry was presented. The dedicated high content tin spectrum standard series was developed. K2S2O7, NaF, Al2O3 and carbon powder were used as buffers and Ge was used as internal standard, and the ratio of sample/matrix/buffer is 1 : 1 : 2. A weak sensitive line (Sn 242. 170 0 nm) was used as the analytical line. The technologies of vertical electrodes, AC arc overlap spectrograph, interception of the exposure, quantitative computer translation spectrum and background correction were used. The determination range is 100-22 350 microg x g(-1), the detection limit is 16.64 microg x g(-1), and the precision is (RSD, n = 12) 4.11%-6.46%. The accuracy of the method has been verified by determination of high content of tin in national geochemical standard samples and the results are in agreement with certified value. The method can be used for measurement directly without dilution of high content of tin in geochemical samples, and it greatly improved the detection upper limit for the determination of tin with solid emission spectroscopy and has certain practical value.

  5. The content and role of formal contracts in high-tech alliances

    NARCIS (Netherlands)

    de Jong, Gjalt; Woolthuis, Rosalinde Ja Klein

    2009-01-01

    In this study we investigate the governance structure of innovation processes in high-tech alliances, focusing on the content and role of formal contracts. The design of a formal agreement is one of the most important strategic decisions for alliance partners. Drawing upon transaction cost arguments

  6. Nanoscale high-content analysis using compositional heterogeneities of single proteoliposomes

    DEFF Research Database (Denmark)

    Mathiasen, Signe; Christensen, Sune M.; Fung, Juan José

    2014-01-01

    heterogeneities can severely skew ensemble-average proteoliposome measurements but also enable ultraminiaturized high-content screens. We took advantage of this screening capability to map the oligomerization energy of the β2-adrenergic receptor using ∼10(9)-fold less protein than conventional assays....

  7. Cultural Parallax and Content Analysis: Images of Black Women in High School History Textbooks

    Science.gov (United States)

    Woyshner, Christine; Schocker, Jessica B.

    2015-01-01

    This study investigates the representation of Black women in high school history textbooks. To examine the extent to which Black women are represented visually and to explore how they are portrayed, the authors use a mixed-methods approach that draws on analytical techniques in content analysis and from visual culture studies. Their findings…

  8. Adhesive performance of washed cottonseed meal at high solid contents and low temperatures

    Science.gov (United States)

    Water-washed cottonseed meal (WCSM) has been shown as a promising biobased wood adhesive. Recently, we prepared WSCM in a pilot scale for promoting its industrial application. In this work, we tested the adhesive strength and viscosity of the adhesive preparation with high solid contents (up to 30%...

  9. Volatile constituents of Dianthus rupicola Biv. from Sicily: activity against microorganisms affecting cellulosic objects.

    Science.gov (United States)

    Casiglia, Simona; Bruno, Maurizio; Senatore, Felice

    2014-01-01

    Dianthus rupicola Biv. (cliffs carnation) is a camephytic, suffruticous, perennial plant growing up to 40 cm high. The plant is widespread in Sicily and neighbouring islands (Egadi, Lampedusa, Lipari) and in some areas of southern Italy. GC and GC-MS analyses of the essential oil distilled from the flowers showed the presence of 66 components. Its composition is characterised by the high content of thymol and carvacrol derivatives. A good antibacterial activity against Bacillus cereus and Bacillussubtilis, both infesting cellulosic historical material, was shown, whereas the antioxidant capacity was determined to be quite poor.

  10. Cellulose biogenesis in Dictyostelium discoideum

    Energy Technology Data Exchange (ETDEWEB)

    Blanton, R.L.

    1993-12-31

    Organisms that synthesize cellulose can be found amongst the bacteria, protistans, fungi, and animals, but it is in plants that the importance of cellulose in function (as the major structural constituent of plant cell walls) and economic use (as wood and fiber) can be best appreciated. The structure of cellulose and its biosynthesis have been the subjects of intense investigation. One of the most important insights gained from these studies is that the synthesis of cellulose by living organisms involves much more than simply the polymerization of glucose into a (1{r_arrow}4)-{beta}-linked polymer. The number of glucoses in a polymer (the degree of polymerization), the crystalline form assumed by the glucan chains when they crystallize to form a microfibril, and the dimensions and orientation of the microfibrils are all subject to cellular control. Instead of cellulose biosynthesis, a more appropriate term might be cellulose biogenesis, to emphasize the involvement of cellular structures and mechanisms in controlling polymerization and directing crystallization and deposition. Dictyostelium discoideum is uniquely suitable for the study of cellulose biogenesis because of its amenability to experimental study and manipulation and the extent of our knowledge of its basic cellular mechanisms (as will be evident from the rest of this volume). In this chapter, I will summarize what is known about cellulose biogenesis in D. discoideum, emphasizing its potential to illuminate our understanding both of D. discoideum development and plant cellulose biogenesis.

  11. Evolution of undissolved phases in high-zinc content super-high strength aluminum alloy during ageing

    Institute of Scientific and Technical Information of China (English)

    张坤; 刘志义; 叶呈武; 许晓嫦; 郑青春

    2004-01-01

    The evolution of undissolved phases in the high-zinc content super-high strength aluminum alloy during ageing was investigated by means of SEM and EIS. The results show that undissolved phases of Cu-rich M(AlZnMgCu) exist in the silver-free alloy at solid-solution state. With increasing the ageing time, the precipitation of agehardening precipitates MgZn2 stimulates Zn atoms within the undissolved phases to diffuse into the matrix, and thus the Cu content in the M(AlZnMgCu) phase increases relatively. For the silver-bearing alloy, small addition of Ag promotes the formation of Ag-rich M(A1ZnMgCuAg) undissolved phases and deteriorates mechanical properties of the alloy. At the early stage of ageing, Ag content within the M(AlZnMgCuAg) phases greatly decreases due to rapid diffusing of Ag atoms into the matrix and the co-clustering of Ag and Mg atoms. As the ageing time prolonging, the precipitation of MgZn2 results in the decrease of Zn content in the undissolved phases, and the relative increase of Ag and Mg contents.

  12. High Water Content Material Based on Ba-Bearing Sulphoaluminate Cement

    Institute of Scientific and Technical Information of China (English)

    CHANG Jun; CHENG Xin; LU Lingchao; HUANG Shifeng; YE Zhengmao

    2005-01-01

    A new type of high water content material which is made up of two pastes is prepared, one is made from lime and gypsum, and another is based on Ba-bearing stdphoaluminate cement. It has excellent properties such as slow single paste solidifing,fast double pastes solidifing,fast coagulating and hardening, high early strength, good suspension property at high W/C ratio and low cost. Meanwhile, the properties and hydration mechanism of the material were analyzed by using XRD , DTA- TG and SEM. The hydrated products of new type of high water content material are Ba-bearing ettringite, BaSO4 , aluminum gel and C-S-H gel.

  13. Cellulose nanowhiskers and nanofibers from biomass for composite applications

    Science.gov (United States)

    Wang, Tao

    2011-12-01

    Biological nanocomposites such as plant cell wall exhibit high mechanical properties at a light weight. The secret of the rigidity and strength of the cell wall lies in its main structural component -- cellulose. Native cellulose exists as highly-ordered microfibrils, which are just a few nanometers wide and have been found to be stiffer than many synthetic fibers. In the quest for sustainable development around the world, using cellulose microfibrils from plant materials as renewable alternatives to conventional reinforcement materials such as glass fibers and carbon fibers is generating particular interest. In this research, by mechanical disintegration and by controlled chemical hydrolysis, both cellulose nanofibers and nanowhiskers were extracted from the cell wall of an agricultural waste, wheat straw. The reinforcement performances of the two nanofillers were then studied and compared using the water-soluble polyvinyl alcohol (PVOH) as a matrix material. It was found that while both of these nanofillers could impart higher stiffness to the polymer, the nanofibers from biomass were more effective in composite reinforcement than the cellulose crystals thanks to their large aspect ratio and their ability to form interconnected network structures through hydrogen bonding. One of the biggest challenges in the development of cellulose nanocomposites is achieving good dispersion. Because of the high density of hydroxyl groups on the surface of cellulose, it remains a difficult task to disperse cellulose nanofibers in many commonly used polymer matrices. The present work addresses this issue by developing a water-based route taking advantage of polymer colloidal suspensions. Combining cellulose nanofibers with one of the most important biopolymers, poly(lactic acid) (PLA), we have prepared nanocomposites with excellent fiber dispersion and improved modulus and strength. The bio-based nanocomposites have a great potential to serve as light-weight structural materials

  14. Recent advances in understanding the role of cellulose accessibility in enzymatic hydrolysis of lignocellulosic substrates.

    Science.gov (United States)

    Meng, Xianzhi; Ragauskas, Arthur Jonas

    2014-06-01

    Cellulose accessibility has been proposed as a key factor in the efficient bio-conversion of lignocellulosic biomass to fermentable sugars. Factors affecting cellulose accessibility can be divided into direct factors that refer to accessible surface area of cellulose, and indirect factors referring to chemical composition such as lignin/hemicellulose content, and biomass structure-relevant factors (i.e. particle size, porosity). An overview of the current pretreatment technologies special focus on the major mode of action to increase cellulose accessibility as well as multiple techniques that could be used to assess the cellulose accessibility are presented in this review. The appropriate determination of cellulose accessibility before and after pretreatment can assist to understand the effectiveness of a particular pretreatment in overcoming lignocellulosic recalcitrance to improve substrate enzymatic digestibility. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. The effect of High Pressure and High Temperature processing on carotenoids and chlorophylls content in some vegetables.

    Science.gov (United States)

    Sánchez, Celia; Baranda, Ana Beatriz; Martínez de Marañón, Iñigo

    2014-11-15

    The effect of High Pressure (HP) and High Pressure High Temperature (HPHT) processing on carotenoid and chlorophyll content of six vegetables was evaluated. In general, carotenoid content was not significantly influenced by HP or HPHT treatments (625 MPa; 5 min; 20, 70 and 117 °C). Regarding chlorophylls, HP treatment caused no degradation or slight increases, while HPHT processes degraded both chlorophylls. Chlorophyll b was more stable than chlorophyll a at 70 °C, but both of them were highly degraded at 117 °C. HPHT treatment at 117 °C provided products with a good retention of carotenoids and colour in the case of red vegetables. Even though the carotenoids also remained in the green vegetables, their chlorophylls and therefore their colour were so affected that milder temperatures need to be applied. As an industrial scale equipment was used, results will be useful for future industrial implementation of this technology.

  16. Influence of process water quality on hydrothermal carbonization of cellulose.

    Science.gov (United States)

    Lu, Xiaowei; Flora, Joseph R V; Berge, Nicole D

    2014-02-01

    Hydrothermal carbonization (HTC) is a thermal conversion process that has been shown to be environmentally and energetically advantageous for the conversion of wet feedstocks. Supplemental moisture, usually in the form of pure water, is added during carbonization to achieve feedstock submersion. To improve process sustainability, it is important to consider alternative supplemental moisture sources. Liquid waste streams may be ideal alternative liquid source candidates. Experiments were conducted to systematically evaluate how changes in pH, ionic strength, and organic carbon content of the initial process water influences cellulose carbonization. Results from the experiments conducted evaluating the influence of process water quality on carbonization indicate that changes in initial water quality do influence time-dependent carbonization product composition and yields. These results also suggest that using municipal and industrial wastewaters, with the exception of streams with high CaCl2 concentrations, may impart little influence on final carbonization products/yields.

  17. Using carboxylated nanocrystalline cellulose as an additive in cellulosic paper and poly (vinyl alcohol) fiber paper.

    Science.gov (United States)

    Cha, Ruitao; Wang, Chengyu; Cheng, Shaoling; He, Zhibin; Jiang, Xingyu

    2014-09-22

    Specialty paper (e.g. cigarette paper and battery diaphragm paper) requires extremely high strength properties. The addition of strength agents plays an important role in increasing strength properties of paper. Nanocrystalline cellulose (NCC), or cellulose whiskers, has the potential to enhance the strength properties of paper via improving inter-fibers bonding. This paper was to determine the potential of using carboxylated nanocrystalline cellulose (CNCC) to improve the strength properties of paper made of cellulosic fiber or poly (vinyl alcohol) (PVA) fiber. The results indicated that the addition of CNCC can effectively improve the strength properties. At a CNCC dosage of 0.7%, the tear index and tensile index of the cellulosic paper reached the maximum of 12.8 mN m2/g and 100.7 Nm/g, respectively. More importantly, when increasing the CNCC dosage from 0.1 to 1.0%, the tear index and tensile index of PVA fiber paper were increased by 67.29%, 22.55%, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. High School Science Teachers' Perceptions of Teaching Content-Related Reading Comprehension Instruction

    Science.gov (United States)

    Williams, Theresa

    In order to achieve academic success, students must be able to comprehend written material in content-area textbooks. However, a large number of high school students struggle to comprehend science content. Research findings have demonstrated that students make measurable gains in comprehending content-area textbooks when provided quality reading comprehension instruction. The purpose of this study was to gain an understanding of how high school science teachers perceived their responsibility to provide content-related comprehension instruction and 10 high school science teachers were interviewed for this study. Data analysis consisted of open, axial, and selective coding. The findings revealed that 8 out of the 10 participants believed that it is their responsibility to provide reading comprehension. However, the findings also revealed that the participants provided varying levels of reading comprehension instruction as an integral part of their science instruction. The potential for positive social change could be achieved by teachers and administrators. Teachers may use the findings to reflect upon their own personal feelings and beliefs about providing explicit reading comprehension. In addition to teachers' commitment to reading comprehension instruction, administrators could deliberate about professional development opportunities that might improve necessary skills, eventually leading to better comprehension skills for students and success in their education.

  19. Rapid saccharification for production of cellulosic biofuels.

    Science.gov (United States)

    Lee, Dae-Seok; Wi, Seung Gon; Lee, Soo Jung; Lee, Yoon-Gyo; Kim, Yeong-Suk; Bae, Hyeun-Jong

    2014-04-01

    The economical production of biofuels is hindered by the recalcitrance of lignocellulose to processing, causing high consumption of processing enzymes and impeding hydrolysis of pretreated lignocellulosic biomass. We determined the major rate-limiting factor in the hydrolysis of popping pre-treated rice straw (PPRS) by examining cellulase adsorption to lignin and cellulose, amorphogenesis of PPRS, and re-hydrolysis. Based on the results, equivalence between enzyme loading and the open structural area of cellulose was required to significantly increase productive adsorption of cellulase and to accelerate enzymatic saccharification of PPRS. Amorphogenesis of PPRS by phosphoric acid treatment to expand open structural area of the cellulose fibers resulted in twofold higher cellulase adsorption and increased the yield of the first re-hydrolysis step from 13% to 46%. The total yield from PPRS was increased to 84% after 3h. These results provide evidence that cellulose structure is one of major effects on the enzymatic hydrolysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. 玉米秸秆及纤维素高值化应用的研究进展%Research progress on the high-valuable applications of corn stalks and corn stalks cellulose

    Institute of Scientific and Technical Information of China (English)

    王犇; 潘高峰; 黄科林

    2014-01-01

    文章从玉米产业废弃物玉米秸秆的应用出发,对玉米秸秆从传统方面进行总结,对玉米秸秆纤维素从降解、再生和制备吸附材料三个角度进行高值化应用的综述。%Starting From the applications of corn industry waste corn stalks, This paper summarizes from corn stover traditionally, then the high-value applications of corn stalk cellulose was reviewed from degradation, regeneration and the preparation of the adsorbent material.

  1. Fast repurposing of high-resolution stereo video content for mobile use

    Science.gov (United States)

    Karaoglu, Ali; Lee, Bong Ho; Boev, Atanas; Cheong, Won-Sik; Gotchev, Atanas

    2012-06-01

    3D video content is captured and created mainly in high resolution targeting big cinema or home TV screens. For 3D mobile devices, equipped with small-size auto-stereoscopic displays, such content has to be properly repurposed, preferably in real-time. The repurposing requires not only spatial resizing but also properly maintaining the output stereo disparity, as it should deliver realistic, pleasant and harmless 3D perception. In this paper, we propose an approach to adapt the disparity range of the source video to the comfort disparity zone of the target display. To achieve this, we adapt the scale and the aspect ratio of the source video. We aim at maximizing the disparity range of the retargeted content within the comfort zone, and minimizing the letterboxing of the cropped content. The proposed algorithm consists of five stages. First, we analyse the display profile, which characterises what 3D content can be comfortably observed in the target display. Then, we perform fast disparity analysis of the input stereoscopic content. Instead of returning the dense disparity map, it returns an estimate of the disparity statistics (min, max, meanand variance) per frame. Additionally, we detect scene cuts, where sharp transitions in disparities occur. Based on the estimated input, and desired output disparity ranges, we derive the optimal cropping parameters and scale of the cropping window, which would yield the targeted disparity range and minimize the area of cropped and letterboxed content. Once the rescaling and cropping parameters are known, we perform resampling procedure using spline-based and perceptually optimized resampling (anti-aliasing) kernels, which have also a very efficient computational structure. Perceptual optimization is achieved through adjusting the cut-off frequency of the anti-aliasing filter with the throughput of the target display.

  2. Selection of hybrids and edible citrus species with a high content in the diosmin functional compound. Modulating effect of plant growth regulators on contents.

    Science.gov (United States)

    Marín, F R; Del Río, J A

    2001-07-01

    The purpose of this study is to identify species, hybrids, and cultivars of edible Citrus species with high contents of diosmin as a functional compound and also to identify the developmental progress of the fruit in which it reaches maximum levels; these findings would be useful for extraction purposes and for the modulating effect of plant growth regulators on diosmin content to increase the level of this flavone. The results obtained reveal that the highest contents of diosmin are present in immature fruits of certain varieties of citron (Buda's finger) and lemon (Meyer), whereas the contents in the edible parts of the fruits are irrelevant from a pharmacological point of view. Similarly, it is shown that it is possible to increase the content of this flavone using hormonal treatments (6-benzylaminopurine and 2,4-dichlorophenoxyacetic acid) during the early stages of fruit growth.

  3. Antibacterial activity of nanocomposites of copper and cellulose.

    Science.gov (United States)

    Pinto, Ricardo J B; Daina, Sara; Sadocco, Patrizia; Pascoal Neto, Carlos; Trindade, Tito

    2013-01-01

    The design of cheap and safe antibacterial materials for widespread use has been a challenge in materials science. The use of copper nanostructures combined with abundant biopolymers such as cellulose offers a potential approach to achieve such materials though this has been less investigated as compared to other composites. Here, nanocomposites comprising copper nanofillers in cellulose matrices have been prepared by in situ and ex situ methods. Two cellulose matrices (vegetable and bacterial) were investigated together with morphological distinct copper particulates (nanoparticles and nanowires). A study on the antibacterial activity of these nanocomposites was carried out for Staphylococcus aureus and Klebsiella pneumoniae, as pathogen microorganisms. The results showed that the chemical nature and morphology of the nanofillers have great effect on the antibacterial activity, with an increase in the antibacterial activity with increasing copper content in the composites. The cellulosic matrices also show an effect on the antibacterial efficiency of the nanocomposites, with vegetal cellulose fibers acting as the most effective substrate. Regarding the results obtained, we anticipate the development of new approaches to prepare cellulose/copper based nanocomposites thereby producing a wide range of interesting antibacterial materials with potential use in diverse applications such as packaging or paper coatings.

  4. Photoluminescence efficiency of BGaN epitaxial layers with high boron content

    Energy Technology Data Exchange (ETDEWEB)

    Jurkevičius, J.; Mickevičius, J., E-mail: juras.mickevicius@ff.vu.lt; Kadys, A.; Kolenda, M.; Tamulaitis, G.

    2016-07-01

    High-boron-content epitaxial layers of BGaN intended for lattice-matching with AlGaN in UV light emitters were grown on SiC substrate and GaN and AlN templates on sapphire. Photoluminescence (PL) of these layers was studied under quasi-steady-state conditions by varying temperature and excitation intensity. The PL spectra in the samples with different boron content and their dynamics evidence formation of boron-rich regions occupying a small fraction of the total layer volume and acting as the emission killers. The room-temperature PL efficiency of the BGaN epilayers was estimated and shown to drastically decrease at increasing boron content with no significant correlation with either the type of substrate/template or technological conditions of the layer deposition.

  5. Determination of Ge content in high concentration Ge-doped Czochralski Si single crystals by FTIR

    Institute of Scientific and Technical Information of China (English)

    JIANG Zhongwei; ZHANG Weilian; NIU Xinhuan

    2005-01-01

    SiGe single crystals with different Ge concentrations were measured by Fourier transform infrared (FTIR) spectroscopy at room temperature (RT) and 10 K. A new peak appears at the wave number of 710 cm-1 and the spectroscopy becomes clearer with an increase in Ge content. The absorption strength and wave sharp of the 710 cm-1 peak are independent of temperature. The relation of the absorption coefficient amax, the band width of half maximum (BWHM) W1/2 of the 710 cm-1 peak, and the Ge concentration is determined with the Ge content obtained by SEM-EDX. The conversion factor is k = 1.211 at 10 K. Therefore, the Ge content in high concentration Ge doped CZ-Si single crystals can be determined by FTIR.

  6. Structure and Content Analysis for Vocational High School Website in Indonesia

    Science.gov (United States)

    Subagja, H.; Abdullah, A. G.; Trisno, B.; Nandiyanto, A. B. D.

    2017-03-01

    Statistics about the condition of the school’s website in Indonesia is still difficult. This study aims to determine website quality in terms of completeness of content’s criteria of Vocational High School (VHS) in West Java, Indonesia. The method used is the content analysis and survey. Content analysis is reviewing the documents comprising the general category, while the survey is a observation process to get the facts from 272 school websites. Aspects of the structure and content of school website are including institutional information, educators and education personnel, curriculum, student, infrastructure, school achievement, and public access. The results of this study showed the average quality of the VHS website in West Java is still low. The recommendations are needed to improve the quality of the school website.

  7. Deposition of High Conductivity Low Silver Content Materials by Screen Printing

    Directory of Open Access Journals (Sweden)

    Eifion Jewell

    2015-05-01

    Full Text Available A comprehensive experimental investigation has been carried out into the role of film thickness variation and silver material formulation on printing capability in the screen printing process. A full factorial experiment was carried out where two formulations of silver materials were printed through a range of screens to a polyester substrate under a set of standard conditions. The materials represented a novel low silver content (45%–49% polymer material and traditional high silver content (65%–69% paste. The resultant prints were characterised topologically and electrically. The study shows that more cost effective use of the silver in the ink was obtained with the low silver polymer materials, but that the electrical performance was more strongly affected by the mesh being used (and hence film thickness. Thus, while optimum silver use could be obtained using materials with a lower silver content, this came with the consequence of reduced process robustness.

  8. A High Resolution Capacitive Sensing System for the Measurement of Water Content in Crude Oil

    Directory of Open Access Journals (Sweden)

    Muhammad Zubair Aslam

    2014-06-01

    Full Text Available This paper presents the design of a non-intrusive system to measure ultra-low water content in crude oil. The system is based on a capacitance to phase angle conversion method. Water content is measured with a capacitance sensor comprising two semi-cylindrical electrodes mounted on the outer side of a glass tube. The presence of water induces a capacitance change that in turn converts into a phase angle, with respect to a main oscillator. A differential sensing technique is adopted not only to ensure high immunity against temperature variation and background noise, but also to eliminate phase jitter and amplitude variation of the main oscillator that could destabilize the output. The complete capacitive sensing system was implemented in hardware and experiment results using crude oil samples demonstrated that a resolution of ±50 ppm of water content in crude oil was achieved by the proposed design.

  9. Reduction of phorbol ester content in jatropha cake using high energy gamma radiation

    Directory of Open Access Journals (Sweden)

    Runumi Gogoi

    2014-07-01

    Full Text Available In this paper, an attempt has been made to remove phorbol ester present in jatropha cake by exposing it to gamma radiation. A sensitizer was also used to accelerate the degradation of phorbol esters. The phorbol ester content in the cake was estimated by high performance liquid chromatography (HPLC. It was observed that gamma irradiation of the jatropha seed cake was effective in reducing the phorbol ester content. Originally, the phorbol ester content in the cake was found as 0.29 mg/g, which on exposure to radiation was reduced by 33.4% and 96% with radiation dose of 30 and 125 kGy respectively. The presence of a sensitizer was found to enhances the susceptibility of phorbol esters degradation by oxidative degradation on exposure to ionizing radiation.

  10. SULFUR DIOXIDE AND AMMONIA GAS REDUCTION USING COCONUT CELLULOSE AND ACETYLATED CELLULOSE

    Directory of Open Access Journals (Sweden)

    SURJANI WONORAHARDJO

    2016-07-01

    Full Text Available Some adsorbent materials were employed to reduce ammonia and carbon dioxide gases. Cellulose materials from nata de coco and grated coconut meat were packed in a column to be used as gas adsorbent. The effect of surface modification of cellulose by acetylation in order to enhance the sorption ability and capacity was also studied. Another factor that was tested was the column length. The characteristics of cellulose materials were done by electron microscopy, infrared spectroscopy, and physical parameters such as water and ash contents as well as iodine sorption ability. The amount of ammonia and sulfur dioxide gases absorbed by the materials were analyzed by visible spectroscopy. The results showed that the cellulose material can be good adsorbent for basic gas like ammonia as well as acidic sulfur dioxide gases. Acetylation as a method of surface modification gave the proof of better sorption for both gases but was greater for ammonia. However, the column length gave greater impact in ammonia compared to sulfur dioxide. This study provides a better explanation of dynamics at surfaces, in the search for better adsorbents.

  11. A review on chitosan-cellulose blends and nanocellulose reinforced chitosan biocomposites: Properties and their applications.

    Science.gov (United States)

    H P S, Abdul Khalil; Saurabh, Chaturbhuj K; A S, Adnan; Nurul Fazita, M R; Syakir, M I; Davoudpour, Y; Rafatullah, M; Abdullah, C K; M Haafiz, M K; Dungani, R

    2016-10-01

    Chitin is one of the most abundant natural polymers in world and it is used for the production of chitosan by deacetylation. Chitosan is antibacterial in nature, non-toxic, and biodegradable thus it can be used for the production of biodegradable film which is a green alternative to commercially available synthetic counterparts. However, their poor mechanical and thermal properties restricted its wide spread applications. Chitosan is highly compatible with other biopolymers thus its blending with cellulose and/or incorporation of nanofiber isolated from cellulose namely cellulose nanofiber and cellulose nanowhiskers are generally useful. Cellulosic fibers in nano scale are attractive reinforcement in chitosan to produce environmental friendly composite films with improved physical properties. Thus chitosan based composites have wide applicability and potential in the field of biomedical, packaging and water treatment. This review summarises properties and preparation procedure of chitosan-cellulose blends and nano size cellulose reinforcement in chitosan bionanocomposites for different applications.

  12. Cellulose aerogel regenerated from ionic liquid solution for immobilized metal affinity adsorption.

    Science.gov (United States)

    Oshima, Tatsuya; Sakamoto, Toshihiko; Ohe, Kaoru; Baba, Yoshinari

    2014-03-15

    Surface morphology of cellulosic adsorbents is expected to influence the adsorption behavior of biomacromolecules. In the present study, cellulose aerogel regenerated from ionic liquid solution was prepared for use as a polymer support for protein adsorption. Iminodiacetic acid groups were introduced to the aerogel for immobilized metal affinity adsorption of proteins. A Cu(II)-immobilized iminodiacetic acid cellulose aerogel (Cu(II)-IDA-CA), which has a large specific surface area, showed a higher adsorption capacity than Cu(II)-immobilized iminodiacetic acid bacterial cellulose (Cu(II)-IDA-BC) and Cu(II)-immobilized iminodiacetic acid plant cellulose (Cu(II)-IDA-PC). In contrast, the Cu(II)-immobilized cellulosic adsorbents showed similar adsorption capacities for smaller amino acid and peptides. The results show that cellulose aerogels are useful as polymer supports with high protein adsorption capacities.

  13. High-Reliability Low-Ag-Content Sn-Ag-Cu Solder Joints for Electronics Applications

    Science.gov (United States)

    Shnawah, Dhafer Abdulameer; Said, Suhana Binti Mohd; Sabri, Mohd Faizul Mohd; Badruddin, Irfan Anjum; Che, Fa Xing

    2012-09-01

    Sn-Ag-Cu (SAC) alloy is currently recognized as the standard lead-free solder alloy for packaging of interconnects in the electronics industry, and high- Ag-content SAC alloys are the most popular choice. However, this choice has been encumbered by the fragility of the solder joints that has been observed in drop testing as well as the high cost of the Ag itself. Therefore, low-Ag-content SAC alloy was considered as a solution for both issues. However, this approach may compromise the thermal-cycling performance of the solders. Therefore, to enhance the thermal-cycling reliability of low-Ag-content SAC alloys without sacrificing their drop-impact performance, alloying elements such as Mn, Ce, Ti, Bi, In, Sb, Ni, Zn, Al, Fe, and Co were selected as additions to these alloys. However, research reports related to these modified SAC alloys are limited. To address this paucity, the present study reviews the effect of these minor alloying elements on the solder joint reliability of low-Ag-content SAC alloys in terms of thermal cycling and drop impact. Addition of Mn, Ce, Bi, and Ni to low-Ag-content SAC solder effectively improves the thermal-cycling reliability of joints without sacrificing the drop-impact performance. Taking into consideration the improvement in the bulk alloy microstructure and mechanical properties, wetting properties, and growth suppression of the interface intermetallic compound (IMC) layers, addition of Ti, In, Sb, Zn, Al, Fe, and Co to low-Ag-content SAC solder has the potential to improve the thermal-cycling reliability of joints without sacrificing the drop-impact performance. Consequently, further investigations of both thermal-cycling and drop reliability of these modified solder joints must be carried out in future work.

  14. S-RHT FIXED-BED HYDROTREATING TECHNOLOGY FOR RESIDUE WITH HIGH SULFUR CONTENT

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    To meet the demands of processing residue with high sulfur content, Fushun Research Institute of Petroleum and Petrochemicals (FRIPP) successfully developed the fixed-bed residue hydrotreating technology (S-RHT), which is suitable for treating high sulfur residue to produce diesel oil with low sulfur content. the hydrotreated 350 ℃+ residue is also a good feedstock for RFCC. Based on this technology, Maoming Petrochemical Company constructed the hydrotreating unit with a capacity of 2 Mt/a to treat high sulfur residue, in which loaded FZC series catalysts were developed by FRIPP. The unit was first put into commercial operation at the end of 1999. The commercial operation showed that the catalysts have good activities and the products meet the designed specifications.

  15. Smart Cellulose Fibers Coated with Carbon Nanotube Networks

    Directory of Open Access Journals (Sweden)

    Haisong Qi

    2014-11-01

    Full Text Available Smart multi-walled carbon nanotube (MWCNT-coated cellulose fibers with a unique sensing ability were manufactured by a simple dip coating process. The formation of electrically-conducting MWCNT networks on cellulose mono- and multi-filament fiber surfaces was confirmed by electrical resistance measurements and visualized by scanning electron microscopy. The interaction between MWCNT networks and cellulose fiber was investigated by Raman spectroscopy. The piezoresistivity of these fibers for strain sensing was investigated. The MWCNT-coated cellulose fibers exhibited a unique linear strain-dependent electrical resistance change up to 18% strain, with good reversibility and repeatability. In addition, the sensing behavior of these fibers to volatile molecules (including vapors of methanol, ethanol, acetone, chloroform and tetrahydrofuran was investigated. The results revealed a rapid response, high sensitivity and good reproducibility for these chemical vapors. Besides, they showed good selectivity to different vapors. It is suggested that the intrinsic physical and chemical features of cellulose fiber, well-formed MWCNT networks and favorable MWCNT-cellulose interaction caused the unique and excellent sensing ability of the MWCNT-coated cellulose fibers, which have the potential to be used as smart materials.

  16. Enhanced cellulose degradation using cellulase-nanosphere complexes.

    Directory of Open Access Journals (Sweden)

    Craig Blanchette

    Full Text Available Enzyme catalyzed conversion of plant biomass to sugars is an inherently inefficient process, and one of the major factors limiting economical biofuel production. This is due to the physical barrier presented by polymers in plant cell walls, including semi-crystalline cellulose, to soluble enzyme accessibility. In contrast to the enzymes currently used in industry, bacterial cellulosomes organize cellulases and other proteins in a scaffold structure, and are highly efficient in degrading cellulose. To mimic this clustered assembly of enzymes, we conjugated cellulase obtained from Trichoderma viride to polystyrene nanospheres (cellulase:NS and tested the hydrolytic activity of this complex on cellulose substrates from purified and natural sources. Cellulase:NS and free cellulase were equally active on soluble carboxymethyl cellulose (CMC; however, the complexed enzyme displayed a higher affinity in its action on microcrystalline cellulose. Similarly, we found that the cellulase:NS complex was more efficient in degrading natural cellulose structures in the thickened walls of cultured wood cells. These results suggest that nanoparticle-bound enzymes can improve catalytic efficiency on physically intractable substrates. We discuss the potential for further enhancement of cellulose degradation by physically clustering combinations of different glycosyl hydrolase enzymes, and applications for using cellulase:NS complexes in biofuel production.

  17. Cellulosic ethanol: status and innovation

    Energy Technology Data Exchange (ETDEWEB)

    Lynd, L; Liang, Xiaoyu; Biddy, Mary; Allee, Andrew; Cai, Hao; Foust, Thomas; Himmel, Michael E.; Laser, Mark; Wang, Michael; Wyman, Charles

    2017-01-01

    Although the purchase price of cellulosic feedstocks is competitive with petroleum on an energy basis, the cost of lignocellulose conversion to ethanol using today’s technology is high. Cost reductions can be pursued via either in-paradigm or new-paradigm innovation. As an example of new-paradigm innovation, consolidated bioprocessing using thermophilic bacteria combined with milling during fermentation (cotreatment) is analyzed. Acknowledging the nascent state of this approach, our analysis indicates potential for radically improved cost competitiveness and feasibility at smaller scale compared to current technology, arising from (a) R&D-driven advances (consolidated bioprocessing with cotreatment in lieu of thermochemical pretreatment and added fungal cellulase), and (b) configurational changes (fuel pellet coproduction instead of electricity, gas boiler(s) in lieu of a solid fuel boiler).

  18. Acetoacetylation of Hydroxyethyl Cellulose

    Institute of Scientific and Technical Information of China (English)

    陈晓锋; 高彦芳; 杜奕; 刘德山

    2002-01-01

    The acetoacetyl group can be used to improve superabsorbent resins since it is more active than the hydroxyethyl group. The acetoacetyl group can be introduced into the side group of hydroxyethyl cellulose (HEC) to activate HEC using the ester exchange reaction between HEC and ethyl acetoacetate (EAA) to improve HEC grafting. This paper discusses the main factors affecting the reaction, such as the amount of EAA and catalyzer, the reaction temperature, and the reaction time. The acetoacetyl group was successfully introduced into HEC. Within specified ranges, increasing the amount of EAA, the reaction temperature and the reaction time will increase the acetoacetylation.

  19. Influence of Crystal Allomorph and Crystallinity on the Products and Behavior of Cellulose during Fast Pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Mukarakate, Calvin; Mittal, Ashutosh; Ciesielski, Peter N.; Budhi, Sridhar; Thompson, Logan; Iisa, Kristiina; Nimlos, Mark R.; Donohoe, Bryon S.

    2016-09-06

    Cellulose is the primary biopolymer responsible for maintaining the structural and mechanical integrity of cell walls and, during the fast pyrolysis of biomass, may be restricting cell wall expansion and inhibiting phase transitions that would otherwise facilitate efficient escape of pyrolysis products. Here, we test whether modifications in two physical properties of cellulose, its crystalline allomorph and degree of crystallinity, alter its performance during fast pyrolysis. We show that both crystal allomorph and relative crystallinity of cellulose impact the slate of primary products produced by fast pyrolysis. For both cellulose-I and cellulose-II, changes in crystallinity dramatically impact the fast pyrolysis product portfolio. In both cases, only the most highly crystalline samples produced vapors dominated by levoglucosan. Cellulose-III, on the other hand, produces largely the same slate of products regardless of its relative crystallinity and produced as much or more levoglucosan at all crystallinity levels compared to cellulose-I or II. In addition to changes in products, the different cellulose allomorphs affected the viscoelastic properties of cellulose during rapid heating. Real-time hot-stage pyrolysis was used to visualize the transition of the solid material through a molten phase and particle shrinkage. SEM analysis of the chars revealed additional differences in viscoelastic properties and molten phase behavior impacted by cellulose crystallinity and allomorph. Regardless of relative crystallinity, the cellulose-III samples displayed the most obvious evidence of having transitioned through a molten phase.

  20. Effect of late planting and shading on cellulose synthesis during cotton fiber secondary wall development.

    Directory of Open Access Journals (Sweden)

    Ji Chen

    Full Text Available Cotton-rapeseed or cotton-wheat double cropping systems are popular in the Yangtze River Valley and Yellow River Valley of China. Due to the competition of temperature and light resources during the growing season of double cropping system, cotton is generally late-germinating and late-maturing and has to suffer from the coupling of declining temperature and low light especially in the late growth stage. In this study, late planting (LP and shading were used to fit the coupling stress, and the coupling effect on fiber cellulose synthesis was investigated. Two cotton (Gossypium hirsutum L. cultivars were grown in the field in 2010 and 2011 at three planting dates (25 April, 25 May and 10 June each with three shading levels (normal light, declined 20% and 40% PAR. Mean daily minimum temperature was the primary environmental factor affected by LP. The coupling of LP and shading (decreased cellulose content by 7.8%-25.5% produced more severe impacts on cellulose synthesis than either stress alone, and the effect of LP (decreased cellulose content by 6.7%-20.9% was greater than shading (decreased cellulose content by 0.7%-5.6%. The coupling of LP and shading hindered the flux from sucrose to cellulose by affecting the activities of related cellulose synthesis enzymes. Fiber cellulose synthase genes expression were delayed under not only LP but shading, and the coupling of LP and shading markedly postponed and even restrained its expression. The decline of sucrose-phosphate synthase activity and its peak delay may cause cellulose synthesis being more sensitive to the coupling stress during the later stage of fiber secondary wall development (38-45 days post-anthesis. The sensitive difference of cellulose synthesis between two cultivars in response to the coupling of LP and shading may be mainly determined by the sensitiveness of invertase, sucrose-phosphate synthase and cellulose synthase.