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Sample records for mesoporous phenol-formaldehyde resins

  1. RELATION BETWEEN MECHANICAL PROPERTIES AND PYROLYSIS TEMPERATURE OF PHENOL FORMALDEHYDE RESIN FOR GAS SEPARATION MEMBRANES

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    MONIKA ŠUPOVÁ

    2012-03-01

    Full Text Available The aim of this paper has been to characterize the relation between the pyrolysis temperature of phenol-formaldehyde resin, the development of a porous structure, and the mechanical properties for the application of semipermeable membranes for gas separation. No previous study has dealt with this problem in its entirety. Phenol-formaldehyde resin showed an increasing trend toward micropore porosity in the temperature range from 500 till 1000°C, together with closure of mesopores and macropores. Samples cured and pyrolyzed at 1000°C pronounced hysteresis of desorption branch. The ultimate bending strength was measured using a four-point arrangement that is more suitable for measuring of brittle materials. The chevron notch technique was used for determination the fracture toughness. The results for mechanical properties indicated that phenol-formaldehyde resin pyrolyzates behaved similarly to ceramic materials. The data obtained for the material can be used for calculating the technical design of gas separation membranes.

  2. Thermal and mechanical behavior of modified phenol formaldehyde resin

    International Nuclear Information System (INIS)

    Polyamide is a modifier which introduces flexibility and toughness to phenolic foam by non reactive approach. Phenol formaldehyde resin was physically modified by the addition of polyamide in different percentages ranging from 0.05% to 0.2% which introduced toughness to modified resole. The resultant polymers were characterized by thermal and mechanical analysis using Thermogravimetric Analyzer (TGA), Instron machine and Dynamic Mechanical Analyzer (DMA). (author)

  3. Electron beam curable phenol-formaldehyde resin

    International Nuclear Information System (INIS)

    The novolac type phenolic resins were synthesized and electron beam curing was carried out to the prepolymer obtained by the reaction of the phenolic resin and glycidyl meth acrylate in the presence of triethylbenzyl ammonium chloride. When the prepolymer and its mixtures with monomers were irradiated using electron beams at a dose rate of 3 Mrad/sec, the curing were completed at a dose 2.5 and 3 Mrad respectively. The effects of oxygen and that of hydroxyl group in the prepolymer on electron beam curing were also examined. (author)

  4. Process for preparing phenolic formaldehyde resole resin products derived from fractionated fast-pyrolysis oils

    Science.gov (United States)

    Chum, Helena L. (Arvada, CO); Kreibich, Roland E. (Auburn, WA)

    1992-01-01

    A process for preparing phenol-formaldehyde resole resins and adhesive compositions in which portions of the phenol normally contained in said resins are replaced by a phenol/neutral fractions extract obtained from fractionating fast-pyrolysis oils.

  5. CHARACTERIZATION OF ALKALINE LIGNINS FOR USE IN PHENOL-FORMALDEHYDE AND EPOXY RESINS

    OpenAIRE

    Nour Eddine El Mansouri,; Qiaolong Yuan Mail; Farong Huang

    2011-01-01

    Besides polyurethanes and polyesters, phenolic and epoxy resins are the most prominent applications for technical lignins in thermosetting materials. To evaluate the potential application of lignin raw materials in phenol formaldehyde and epoxy resins, three types of alkaline lignins were characterized in terms of their structures and thermal properties. The lignin samples analyzed were kraft lignin (LIG-1), soda–rice straw lignin (LIG-2), and soda-wheat straw lignin (LIG-3). FTIR and 1H-NMR ...

  6. HPLC Characterization of Phenol-Formaldehyde Resole Resin Used in Fabrication of Shuttle Booster Nozzles

    Science.gov (United States)

    Young, Philip R.

    1999-01-01

    A reverse phase High Performance Liquid Chromatographic method was developed to rapidly fingerprint a phenol-formaldehyde resole resin similar to Durite(R) SC-1008. This resin is used in the fabrication of carbon-carbon composite materials from which Space Shuttle Solid Rocket Booster nozzles are manufactured. A knowledge of resin chemistry is essential to successful composite processing and performance. The results indicate that a high quality separation of over 35 peaks in 25 minutes were obtained using a 15 cm Phenomenex LUNA C8 bonded reverse phase column, a three-way water-acetonitrile-methanol nonlinear gradient, and LTV detection at 280 nm.

  7. Demonstration of contact sensitizers in resins and products based on phenol-formaldehyde.

    Science.gov (United States)

    Bruze, M; Persson, L; Trulsson, L; Zimerson, E

    1986-03-01

    12 phenol-formaldehyde resins were investigated with regard to the presence of 14 contact sensitizers by using high-pressure liquid chromatography. The allergens consisted of simple methylol phenols, dihydroxydiphenyl methanes, 4,4(1)-dihydroxy-(hydroxymethyl)-diphenyl methanes and 2,4(1)-dihydroxy-(hydroxymethyl)-diphenyl methanes. Four substances, 2,4-dimethylol phenol, 2,6-dimethylol phenol, 4,4(1)-dihydroxydiphenyl methane and 2,4(1)-dihydroxydiphenyl methane, were isolated from a resol resin and identified by mass-spectrometry and nuclear magnetic resonance spectrometry. The highest concentrations (up to 15% w/w) of allergens were noted for methylol phenols in resol resins based on phenol and formaldehyde. The corresponding novolak resins showed a high content of dihydroxydiphenyl methanes. There was great variation in concentration of the sensitizers between the resins. None of these sensitizers were demonstrated in the resin based on paratertiary-butyl phenol. Products based on phenol-formaldehyde resins were also investigated for the presence of allergens. Uncured impregnated paper for laminate production and uncured mineral wool contained the same concentrations of the sensitizers as some of the resins studied. The curing process decreased the content of all the allergens investigated in all products, but the sensitizers did not disappear, and they may thus be present in finished products. PMID:3709159

  8. Study on the pyrolysis of phenol-formaldehyde (PF) resin and modified PF resin

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jigang, E-mail: wangjigang@seu.edu.cn [Jiangsu Key Laboratory of Advanced Metallic Materials, School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Jiang, Haiyun [Jiangsu Key Laboratory of Advanced Metallic Materials, School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); School of Materials Science and Engineering, Southeast University, Nanjing Institute of Technology, Nanjing 210013 (China); Jiang, Nan [Institute of Theoretical and Computational Chemistry, Nanjing University, Nanjing 210093 (China)

    2009-12-10

    The pyrolysis of pure phenol-formaldehyde (PF) resin and boron carbide (B{sub 4}C) modified PF resin was investigated by using thermogravimetry (TG) and pyrolysis gas-chromatography-mass-spectrometry (PY-GC/MS). Scanning electron microscope (SEM) and Fourier transform infrared (FT-IR) spectroscopy were also employed to investigate the micro-structural evolution. It was shown from the TG analysis that the char residues of pure PF resin were 62.9 and 60.5% after being pyrolyzed at 700 and 1000 {sup o}C, respectively. The degradation and failure of the resin matrix were mainly resulted from the release of volatiles. The phenol and its methyl derivates took a large proportion in the amount of volatiles. In comparison with the pure PF resin, the char residues of B{sub 4}C modified PF resin were obviously higher, with the values of 71.9 and 68.4% at 700 and 1000 {sup o}C, respectively. Due to the oxidation-reduction reactions between B{sub 4}C additive and oxygen-containing volatiles including CO and H{sub 2}O, partial carbon and oxygen elements in the volatiles remained in the resin matrix in the forms of amorphous carbon and B{sub 2}O{sub 3}, respectively. The results of SEM and FT-IR characterization demonstrated the occurrence of the modification, and the amorphous carbon existed in the form of reticular substance. In addition, the amount of the released phenol and its methyl derivates was also decreased drastically due to the formation of borate.

  9. CHARACTERIZATION OF ALKALINE LIGNINS FOR USE IN PHENOL-FORMALDEHYDE AND EPOXY RESINS

    Directory of Open Access Journals (Sweden)

    Nour Eddine El Mansouri

    2011-05-01

    Full Text Available Besides polyurethanes and polyesters, phenolic and epoxy resins are the most prominent applications for technical lignins in thermosetting materials. To evaluate the potential application of lignin raw materials in phenol formaldehyde and epoxy resins, three types of alkaline lignins were characterized in terms of their structures and thermal properties. The lignin samples analyzed were kraft lignin (LIG-1, soda–rice straw lignin (LIG-2, and soda-wheat straw lignin (LIG-3. FTIR and 1H-NMR methods were used to determine their structure. Gel permeation chromatography (GPC was used to determine the molecular weight distribution (MWD. Differential scanning calorimetry (DSC was used to measure the glass transition temperature (Tg, and thermogravimetric analysis (TGA to determine the thermal stability of lignin samples. Results showed that kraft lignin (LIG-1 has moderate hydroxyl-group content, is rich in G-type units, and has good thermal stability. These properties make it more suitable for direct use in phenol formaldehyde resins, and it is therefore a good raw material for this purpose. The alkaline soda-rice straw lignin (LIG-2 with a high hydroxyl-group content and excellent thermal stability is most suited to preparing lignin-based epoxy resins.

  10. Fluorescent glutathione probe based on MnO2-phenol formaldehyde resin nanocomposite.

    Science.gov (United States)

    Wang, Xudong; Wang, Dan; Guo, Yali; Yang, Chengduan; Liu, Xiaoyu; Iqbal, Anam; Liu, Weisheng; Qin, Wenwu; Yan, Dan; Guo, Huichen

    2016-03-15

    MnO2-phenol formaldehyde resin (MnO2-PFR) nanocomposite is successfully prepared by a simple chemical reduction process. The resultant MnO2-PFR nanocomposite is well characterized. The absorption band of non-fluorescent MnO2 nanosheets overlaps well with the fluorescence emission of PFR nanoparticles. The green fluorescence of PFR in this nanocomposite can be effectively quenched by fluorescence resonance energy transfer from PFR to MnO2. In the presence of glutathione (GSH), the fluorescence of PFR could be recovered due to MnO2 was reduced to Mn(2+) by GSH. The nanocomposite can be use for detecting glutathione in blood serum. PMID:26426853

  11. Effect of nanosilica on characteristics of carbonizates of phenol-formaldehyde resin - Fe(acac)3

    Science.gov (United States)

    Gun'ko, V. M.; Bogatyrov, V. M.; Oranska, O. I.; Galaburda, M. V.; Polshin, E. V.; Urubkov, I. V.; Leboda, R.; Skubiszewska-Zi?ba, J.; Charmas, B.

    2013-01-01

    A series of carbon-iron-silica (CIS) composites (carbonizates) were prepared by carbonization of phenol-formaldehyde resin - Fe(III) acetylacetonate mixtures with addition of different amount of nanosilica A380 and compared with a composite prepared without silica (CFe composite). The characteristics of the composites differ because two type iron silicates were formed at a surface of silica nanoparticles and affected structure of carbon-iron phases. The textural characteristics of the CIS composites show a decrease in meso- and macroporosity and an increase in nanoporosity because new nanoparticles are formed in voids between silica nanoparticles. The CFe particles, including graphite-like structures, metallic iron nanoparticles and Fe3C, are larger than the CIS particles, which also include iron silicates, amorphous and crystalline silica. The presence of metallic ?-Fe nanoparticles can provide the magnetic properties of the composites.

  12. A Microfluidic Chip Using Phenol Formaldehyde Resin for Uniform-Sized Polycaprolactone and Chitosan Microparticle Generation

    Directory of Open Access Journals (Sweden)

    Wan-Chen Hsieh

    2013-06-01

    Full Text Available This study develops a new solvent-compatible microfluidic chip based on phenol formaldehyde resin (PFR. In addition to its solvent-resistant characteristics, this microfluidic platform also features easy fabrication, organization, decomposition for cleaning, and reusability compared with conventional chips. Both solvent-dependent (e.g., polycaprolactone and nonsolvent-dependent (e.g., chitosan microparticles were successfully prepared. The size of emulsion droplets could be easily adjusted by tuning the flow rates of the dispersed/continuous phases. After evaporation, polycaprolactone microparticles ranging from 29.3 to 62.7 ?m and chitosan microparticles ranging from 215.5 to 566.3 ?m were obtained with a 10% relative standard deviation in size. The proposed PFR microfluidic platform has the advantages of active control of the particle size with a narrow size distribution as well as a simple and low cost process with a high throughput.

  13. Study on preparation and properties of phenol-formaldehyde-chinese fir liquefaction copolymer resin

    Scientific Electronic Library Online (English)

    Ruihang, Lin; Jin, Sun; Chao, Yue; Xiaobo, Wang; Dengyu, Tu; Zhenzhong, Gao.

    2014-05-01

    Full Text Available A new zero-waste and zero-pollution composite adhesive labeled Chinese fir-based adhesive for exterior plywood was synthesized by blending alkaline Chinese fir (Cunninghamia lanceolata) liquid with a small amount of phenol-formaldehyde (PF). The free phenol and free formaldehyde content of the Chine [...] se fir-based adhesive were sharply decreased compared to normal PF resin by more than 50%. The synthetic adhesive show with excellent water resistance and environmental friendliness, which had a 28h boil-dry-boil wet bonding strength of 1,73MPa according to standard JIS K6806-2003 and a formaldehyde emission of 0,045mg/L according to standard JIS A1460-2003. The structural properties and their thermal properties of cured adhesives were evaluated using Fourier transform infrared (FT-IR) and differential scanning calorimetry (DSC). The FT-IR analysis confirmed the expected chemical structure as the Chinese fir liquid reacted with formaldehyde and phenol which occurred at the wavenumbers of 1733, 1698, 1652cm-1 and 1077, 1048 cm-1. Although the DSC results indicated that the Chinese fir-based adhesive's curing need higher temperature than the control PF resin, the higher curing temperature hardly cripple the availability of Chinese fir-based resin in the plywood production.

  14. PEMBUATAN AYAKAN MOLEKULER BERBASIS KARBON UNTUK PEMISAHAN N2/O2 DARI PIROLISIS RESIN PHENOL FORMALDEHYDE

    Directory of Open Access Journals (Sweden)

    Imam Prasetyo

    2012-02-01

    Full Text Available Proses pemisahan campuran gas dengan menggunakan carbon molecular sieve (CMS atau ayakan molekuler berbasis karbon merupakan teknologi proses pemisahan yang mulai banyak diterapkan di dalam industri kimia. Dalam penelitian ini, CMS untuk pemisahan N2 dari udara dibuat dari pirolisis bahan polimer sintetis yaitu resin phenol formaldehyde (PF. Prekursor yang berupa resin tersebut dipanaskan dalam retort pada suhu 400-950oC selama 0,5-3 jam yang disertai dengan pengaliran gas N2 ke dalam retort dengan laju 100 mL/jam. Dengan proses pirolisis, atom-atom non-karbon penyusun bahan polimer akan terurai dan menguap sehingga hanya menyisakan arang karbon dengan struktur kerangka atom karbon yang sesuai dengan struktur kerangka dasar rantai polimer. Kemudian karbon hasil prolisis tersebut dipanaskan lebih lanjut pada suhu 750-950oC sambil dialiri gas CO2 selama 1 jam. Pada kondisi ini karbon akan mengalami proses gasifikasi parsial sehingga terbentuk karbon dengan porositas tinggi. Melalui rekayasa proses polimerisasi dan karbonisasi dihasilkan material karbon berpori yang mayoritas porinya adalah mikropori dengan ukuran pori efektif < 2 nm yang dapat dikategorikan sebagai CMS yang dapat dipergunakan untuk memisahkan campuran gas N2-O2.  Pada penelitian ini dihasilkan CMS dengan selektifitas kinetis DN2/DO2 sekitar 3.

  15. Synthesis of carbon-encapsulated iron carbide/iron nanoparticles from phenolic-formaldehyde resin and ferric nitrate

    International Nuclear Information System (INIS)

    Carbon-encapsulated iron carbide/iron nanoparticles have been synthesized on a large scale by the heat treatment of thermal plastic phenolic-formaldehyde resin with the aid of ferric nitrate. The effects of heating temperature on the morphologies and structures of carbonized products were investigated using transmission electron microscope, high-resolution transmission electron microscope and X-ray diffraction measurements. The products with diameter distribution of 20-100 nm consisted mainly of spheroidal nanoparticles separated by hollow onion-like carbon nanoparticles.

  16. Expansive failure reactions and their prevention in the encapsulation of phenol formaldehyde type ion exchange resins in cement based systems

    International Nuclear Information System (INIS)

    Lewatit DN is a phenol formaldehyde based ion exchange resin used to remove radioactive caesium from liquid waste streams such as fuel cooling ponds and effluents. This paper presents the results of a study of the encapsulation of the bead form of the resin in cement with particular reference to the mechanisms of its interaction with the encapsulant. When incorporated in pure ordinary Portland cement (OPC) at loadings in excess of 15 wt % an unstable product results due to expansion of the systems and at higher waste loadings failure results after only a few days. Evidence from differential scanning calorimetry, X-ray diffraction and scanning electron microscopy all indicate the cause of the expansive reaction to be the formation of crystals of calcium salts around and within the resin beads. Addition of BFS and sodium hydroxide prevent the formation of these salts by removal of calcium hydroxide from the system in other reactions. (author)

  17. USE OF LIGNIN SEPARATED FROM BIO-OIL IN ORIENTED STRAND BOARD BINDER PHENOL-FORMALDEHYDE RESINS

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    Badamkhand Sukhbaatar

    2009-05-01

    Full Text Available Bio-oil produced from fast pyrolysis of biomass has been investigated as a renewable fuel and as a source of industrial chemicals. The lignin fraction of bio-oil produced from wood in our fast pyrolysis reactor was separated by using only water and methanol with a 25% yield based on bio-oil weight. This separation procedure appears to be of lower cost than the reported extraction procedure using ethyl acetate as solvent. The isolated pyrolytic lignin was smoothly incorporated into phenol-formaldehyde resins at 30%, 40%, and 50% phenol replacement levels, and the resultant resins were evaluated as oriented strand board core-layer binders. The evaluation results indicated that the pyrolytic lignin is effective for up to about 40% replacement of phenol in synthesizing wood adhesive type PF resins.

  18. Study on the structural evolution of modified phenol-formaldehyde resin adhesive for the high-temperature bonding of graphite

    International Nuclear Information System (INIS)

    A novel adhesive for carbon materials composed of phenol-formaldehyde resin, boron carbide and fumed silica, was prepared. The adhesive property of graphite joints bonded by the above adhesive treated at high-temperatures was tested. Results showed that the adhesive was found to have outstanding high-temperature bonding properties for graphite. The adhesive structure was dense and uniform even after the graphite joints were heat-treated at 1500 deg. C. Bonding strength was 17.1 MPa. The evolution of adhesive structure was investigated. The results indicated that the addition of the secondary additive, fumed silica, improved the bonding performance greatly. Borosilicate phase with better stability was formed during the heat-treatment process, and the volume shrinkage was restrained effectively, which was responsible for the satisfactory high-temperature bonding performance of graphite

  19. Expansive failure reactions and their prevention in the encapsulation of phenol formaldehyde type ion exchange resins in cement based systems

    International Nuclear Information System (INIS)

    Lewatit DN is a phenol formaldehyde based ion exchange resin used to remove radioactive caesium from liquid waste streams such as fuel cooling ponds and effluents. This paper presents the results of a study of the encapsulation of the bead form of the resin in cement with particular reference to the mechanisms of its interaction with the encapsulant. When incorporated in pure ordinary Portland cement (OPC) at loadings in excess of 15 wt% an unstable product results due to expansion of the system and at higher waste loadings failure results after only a few days. The resin beads swell on contact with the alkaline pH environment of the cement but this occurs too rapidly to be the cause of the expansive failure reaction. Increased production of ettringite can also be ruled out as the sulphate concentrations in the resin are too low. Blending the OPC with blast furnace slag (BFS) gives a satisfactory product up to 25 wt% loading and addition of sodium hydroxide to the mix water enables loading of up to 36 wt% to be employed. Evidence from differential scanning calorimetry. X-ray diffraction and scanning electron microscopy all indicate the cause of the expansive reaction to be the formation of crystals of calcium salts around and within the resin beads. Calcium hydroxide, calcium oxalate and calcium carbonate were observed. Addition of BFS and sodium hydroxide prevent the formation of these salts by removal of calcium hydroxide from the system in other reactions. (author)

  20. Assessment of the chemical changes during storage of phenol-formaldehyde resins pyrolysis gas chromatography mass spectrometry, inverse gas chromatography and Fourier transform infra red methods.

    Science.gov (United States)

    Strzemiecka, B; Voelkel, A; Zi?ba-Palus, J; Lachowicz, T

    2014-09-12

    The chemical changes occurring in the phenol-formaldehyde resins (resol and novolac type) during their storage were investigated. In this paper the FT-IR, py-GCMS and inverse gas chromatography methods were applied for assessment of the changes occurring during storage of the phenolic resins. We have found that during storage some examined resins occurred partial curing. The results from all techniques applied are consistent. Py-GCMS is useful technique for screening the storage processes but IGC seems to be most sensitive one. PMID:25092596

  1. Adhesion properties of styrene-butadiene rubber (SBR/Standard Malaysian Rubber (SMR L-based adhesives in the presence of phenol formaldehyde resin

    Directory of Open Access Journals (Sweden)

    2007-10-01

    Full Text Available The adhesion properties, i. e. viscosity, tack and peel strength of styrene-butadiene rubber (SBR/Standard Malaysian Rubber (SMR L-based pressure-sensitive adhesive was studied using phenol formaldehyde resin as the tackifying resin. Toluene was used as the solvent throughout the experiment. SBR composition in SBR/SMR L blend used was 0, 20, 40, 60, 80, 100%. Three different resin loadings, i. e. 40, 80 and 120 parts per hundred parts of rubber (phr were used in the adhesive formulation. The viscosity of adhesive was determined by a HAAKE Rotary Viscometer whereas loop tack and peel strength of paper/polyethylene terephthalate (PET film were measured using a Lloyd Adhesion Tester operating at 30 cm/min. Results indicate that the viscosity of adhesive decreases with increasing % SBR whereas loop tack passes through a maximum value at 20% SBR for all resin loadings. Except for the control sample (without resin, the peel strength shows a maximum value at 60% SBR for the three modes of peel tests. For a fixed % SBR, adhesive sample containing 40 phr phenol formaldehyde resin always exhibits the highest loop tack and peel strength, an observation which is associated to the optimum wettability of adhesive on the substrate.

  2. Photonic patterns printed in chiral nematic mesoporous resins.

    Science.gov (United States)

    Khan, Mostofa K; Bsoul, Anas; Walus, Konrad; Hamad, Wadood Y; MacLachlan, Mark J

    2015-03-27

    Chiral nematic mesoporous phenol-formaldehyde resins, which were prepared using cellulose nanocrystals as a template, can be used as a substrate to produce latent photonic images. These resins undergo swelling, which changes their reflected color. By writing on the films with chemical inks, the density of methylol groups in the resin changes, subsequently affecting their degree of swelling and, consequently, their color. Writing on the films gives latent images that are revealed only upon swelling of the films. Using inkjet printing, it is possible to make higher resolution photonic patterns both as text and images that can be visualized by swelling and erased by drying. This novel approach to printing photonic patterns in resin films may be applied to anti-counterfeit tags, signage, and decorative applications. PMID:25682748

  3. Production of plywood panels from Pinus taeda using veneers of differing densities and phenol-formaldehyde resin with high and low molecular weights

    Directory of Open Access Journals (Sweden)

    Graciela Ines Bolzon de Muniz

    2013-06-01

    Full Text Available This study aimed to evaluate the bonding quality of plywood panels from Pinus taeda using low and high molecular weight phenol-formaldehyde resin and veneers from three different density classes. The experiment consisted of six treatments, each of which produced three panels (replicates. Tests were conducted to evaluate glue line strength to shear stress after two boiling cycles and after 24 hours of cold water immersion. Also determined was the percentage of defects in wood samples. Results indicated that the density classes being assessed differed statistically. However, no significant difference was found between panels produced with high and panels produced with low molecular weight resin as to the mean values of glue line strength, whether subjecting them to two boiling cycles or after 24 hours of cold water immersion. Interactions between different density classes and adhesive formulations were found not significant either. Low molecular weight resin (BPM and panels produced with higher density veneers were found to have better behavior, regarding both bonding strength and percentage of defects. It was concluded that the bonding quality of plywood panels from Pinus taeda was satisfactory after using different densities of veneer and also high and low molecular weight phenolic resins. All treatments were found to comply with minimum requirements established in European standard EN 314-1/1993, which addresses bonding quality of plywood panels.

  4. Novel halogen-free flame retardant thermoset from a hybrid hexakis (methoxymethyl melamine/phosphorus-containing epoxy resin cured with phenol formaldehyde novolac

    Directory of Open Access Journals (Sweden)

    2009-12-01

    Full Text Available This paper describes the curing behaviours, thermal properties and flame-resistance of a novel halogen-free epoxy hybrid thermoset, prepared by the curing reaction of hexakis (methoxymethyl melamine (HMMM, a phosphorouscontaining epoxy resin (EPN-D with 9, 10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO group and phenol formaldehyde novolac (n-PF. The resultant thermosets showed high glass-transition temperatures (Tg, 123–147°C as determined by thermal mechanical analysis (TMA, excellent thermal stability with high 5 wt% decomposition temperatures (Td,5% ??308°C and high char yields (Yc ??39.4 wt% from the thermogravimetric analysis (TGA. All the cured EPND/ HMMM/n-PF hybrid resins achieved the UL 94 V-0 grade with high limited oxygen indices (LOI > 45.7. It is found that phosphorous and nitrogen elements in the cured EPN-D/HMMM/n-PF hybrid resins had a positive synergistic effect on the improvement of the flame retardancy.

  5. Multilayer Hydrophilic Poly(phenol-formaldehyde resin)-Coated Magnetic Graphene for Boronic Acid Immobilization as a Novel Matrix for Glycoproteome Analysis.

    Science.gov (United States)

    Wang, Jiaxi; Wang, Yanan; Gao, Mingxia; Zhang, Xiangmin; Yang, Pengyuan

    2015-07-29

    Capturing glycopeptides selectively and efficiently from mixed biological samples has always been critical for comprehensive and in-depth glycoproteomics analysis, but the lack of materials with superior capture capacity and high specificity still makes it a challenge. In this work, we introduce a way first to synthesize a novel boronic-acid-functionalized magnetic graphene@phenolic-formaldehyde resin multilayer composites via a facile process. The as-prepared composites gathered excellent characters of large specific surface area and strong magnetic responsiveness of magnetic graphene, biocompatibility of resin, and enhanced affinity properties of boronic acid. Furthermore, the functional graphene composites were shown to have low detection limit (1 fmol) and good selectivity, even when the background nonglycopeptides has a concentration 100 fold higher. Additionally, enrichment efficiency of the composites was still retained after being used repeatedly (at least three times). Better yet, the practical applicability of this approach was evaluated by the enrichment of human serum with a low sample volume of 1 ?L. All the results have illustrated that the magG@PF@APB has a great potential in glycoproteome analysis of complex biological samples. PMID:26161682

  6. Characterization of composite materials based on Fe powder (core) and phenol–formaldehyde resin (shell) modified with nanometer-sized SiO2

    Indian Academy of Sciences (India)

    M Stre?ková; J Füzerb; L' Medvecký; R Bureš; P Kollár; M Fáberová; V Girman

    2014-04-01

    Soft magnetic composites based on Fe powder and phenol–formaldehyde resin (PFR) modified with tetraethylorthosilicate are investigated in detail. The chemical synthesis of PFR, its modification with nanometer-sized SiO2 particles created by sol–gel method and subsequent coating, enables a preparation of insulating PFR–SiO2 (PFRT) layer on the surface of Fe particles. Thermal degradation and FTIR analysis of PFR and PFRT with different amount of SiO2 was examined. Mechanical hardness and flexural strength of FePFRT composites was studied depending on the amount of nanosized-SiO2 in the coating. SEM serves in evidence of a defectless microstructure if the coating contains at least 2% of silica particles. The morphology of Fe particles implies uniform coating without any visible exfoliation. A presence of fine SiO2 particles was verified by TEM. The best magnetic properties were found in Fe–PFRT composite with 2% of SiO2 in the insulating layer on behalf of its uniform arrangement and homogeneity.

  7. Evidencia de la biodegradación de resinas fenólicas con hongos ligninolíticos por microscopía electrónica de barrido / Scanning electronic microscopy evidence of phenol-formaldehyde resins biodegradation with ligninolitic fungi

    Scientific Electronic Library Online (English)

    Graciela Ibeth, PONCE ANDRADE; Rafael, VÁZQUEZ DUHALT; Refugio, RODRÍGUEZ VÁZQUEZ; Iliana Ernestina, MEDINA RAMÍREZ; Juan Antonio, LOZANO ÁLVAREZ; Juan, JÁUREGUI RINCÓN.

    2012-05-01

    Full Text Available Los polímeros sintéticos están generando problemas ambientales debido a que generalmente son resistentes a la degradación, sin embargo, investigaciones recientes se han enfocado en métodos biológicos para tratar estos residuos y el desarrollo de plásticos degradables. Los plásticos están clasificado [...] s en dos grandes tipos: termoplásticos y termoestables. Las resinas fenólicas están incluidas dentro de los termoestables, las cuales no pueden ser fundidas por lo tanto no son susceptibles al reciclado y causan un problema ambiental. A través de los estudios acerca de los hongos ligninolíticos se ha determinado que estos organismos producen enzimas extracelulares con alta inespecificidad química e intensa actividad oxidante, lo que les otorga una considerable capacidad para degradar diferentes compuestos orgánicos con estructura similar a la lignina. El objetivo de este trabajo fue demostrar, utilizando microscopía electrónica de barrido que los hongos ligninolíticos tienen la capacidad de degradar las resinas fenólicas. Los resultados demostraron que los hongos Bjerkandera adusta, Pleurotus ostreatus, Phanerochaete chrysosporium y Sporotrichum pulverulentum pueden degradar las resinas fenólicas. Abstract in english Synthetic polymers are growing environmental concern because they are generally nondegradable and recent research has been focused on the biological treatment of plastic wastes and the development of biodegradable plastics. Plastics are classified into two broad types: thermoplastics and thermosetti [...] ng plastics. Phenol-formaldehyde resins (PF resins) are included in the thermosetting plastic category. They are products that once formed cannot be soften, therefore the process for recycling cannot be applied and they cause an environmental problem. Through intensive study of white-rot fungi it has been determined that these organisms produce extracellular enzymes with very low substrate specificity and intense oxidative activity. This makes them suitable for degradation of many different compounds notably organopollutants with structural similarities to lignin. The object of this work was to demonstrate, using scanning electron microscopy, that ligninolitic fungi have the capacity to degrade PF resins. The results showed that the fungi Bjerkandera adusta, Pleurotus ostreatus, Phanerochaete chrysosporium and Sporotrichum pulverulentum can degrade the PF resins.

  8. Investigation of the volatility of toxic elements on the base of phenol-formaldehyde resin in neutron activation analysis

    International Nuclear Information System (INIS)

    The volatility of some elements being determined in biological and environmental samples by NAA (neutron activation analysis) in case of their binding with phenolformaldehyde resin (PFR) is studied. Since the temperature is assumed to influence the volatility of elements stronger than radiation during irradiation of samples in nuclear pile the losses of Se, As, Sb, and Hg form samples on the basis of PFR after their heating at 100-300 deg C have been investigated. It is shown that the losses of Sb and As up to 300 deg C, Se up to 250 deg C, and Hg up to 150 deg C from PFR - based samples do not occur

  9. Adhesion characteristics of phenol formaldehyde pre-preg oil palm stem veneers

    OpenAIRE

    Nor Hafizah Ab. Wahab; Paridah Md. Tahir; Yeoh Beng Hoong; Zaidon Ashaari,; Nor Yuziah Mohd Yunus; Mohd Khairun Anwar Uyup; Mohd Hamami Shahri

    2012-01-01

    The purpose of this study was to evaluate the adhesion properties of phenol formaldehyde-prepreg oil palm veneers that have potential for plywood manufacture. Phenol formaldehyde (PF) resin of three different molecular weights (i.e. 600 (low), 2,000 (medium), and 5,000 (commercial)) were used to pre-treat the veneers. The veneers were soaked in each type of PF resin for 20 seconds, pressed between two rollers, and pre-cured in an oven maintained at 103 ± 2 °C for 24 hours. The volume percent ...

  10. Structure-function investigations of modified phenol-formaldehyde and resorcinol-formaldehyde ion-exchange resins that are selective for cesium

    International Nuclear Information System (INIS)

    Resorcinol-Formaldehyde (R-F) resin is a candidate regenerable ion-exchange material for removal of radioactive cesium from alkaline waste tank supernates at both the Hanford and Savannah River sites. The chemical stability of the R-F resin is a primary issue under the typical process conditions encountered for cesium removal, especially during the acid elution step. Part of our examination into this issue has been directed toward preparation of resins that contain fluorine to examine the effect on chemical stability of resorcinol and phenol based resins and to explore the effect of structural modification of the polymer on its cesium selectivity. Polymer modifiers included 2-, 3-, and 4-fluorophenol as well as 2,5-, 3,4-, and 3,5-difluorophenol. The resins were characterized using spectroscopic techniques (IR, 13C CP-MAS NMR) and by determination of cesium-specific distribution coefficients (Kd's)

  11. Structure and distribution of cross-links in boron-modified phenol-formaldehyde resins designed for soft magnetic composites: a multiple-quantum 11B-11B MAS NMR correlation spectroscopy study.

    Czech Academy of Sciences Publication Activity Database

    Kobera, Libor; Czernek, Ji?í; Stre?ková, M.; Urbanová, Martina; Abbrent, Sabina; Brus, Ji?í

    2015-01-01

    Ro?. 48, ?. 14 (2015), s. 4874-4881. ISSN 0024-9297 R&D Projects: GA MŠk(CZ) LD14010 Grant ostatní: European Commission(XE) COST Action MP1202 HINT Institutional support: RVO:61389013 Keywords : phenol-formaldehyde polymers * boron crosslinks * soft magnetic composites Subject RIV: CD - Macromolecular Chemistry Impact factor: 5.800, year: 2014

  12. Development and Characterization of Phenol - Formaldehyde Molding Powder

    Directory of Open Access Journals (Sweden)

    M .O. Edoga

    2006-01-01

    Full Text Available The synthesis of phenol-formaldehyde resin was carried out at pH 4.0-4.3, formaldehyde to phenol (F/P of 0.881 in the presence of acid catalyst (hydrochloric acid and oxalic acid, at operating temperature and pressure of 115°C and 1 atmospheric pressure respectively. Forty-six grams of the resin produced was formulated into molding powder by incorporating the following: 44.6 grams of water-free- wood-floor, 6.7 g of hexamethylene-tetramine, 2.0 g of magnesium oxide and 1.0 g of magnesium stearate. The determination of pH, viscosity, specific gravity, refractive index, molecular weight and total solid content were carried out at 25°C for both the neat/ conventional P-F resin and the molding powder, while infrared spectrum was performed only on the neat P-F resin. The result obtained showed the sample with water-free-floor (sample y has better mechanochemical properties than the neat sample (simple x. The results for both sample X and Y are: pH valve of 4.11 and 4.5, viscosity of 173.72 and 243.12 poise, refractive index for sample X was 1.67, molecular weight 16967.63 and 25234.54 respectively. The analysis of infrared spectroscopy of sample X showed that at region 3650-3590 cm-1, ­­­there was an absorption whose peak was between sharp and weak and is also O-H stretch-free indicating presence of phenol. The intensity of absorption at region 2800-2700cm-1 is medium indicating C-H stretching vibration of -CHO presence confirming aldelydes. Hence the physiochemical properties and the intra-red spectrum compared well with literature values.

  13. Phenol-formaldehyde oligomers application for coatings production ?????????? ????????????????????? ?????????? ??? ???????????? ????????? ??????????

    Directory of Open Access Journals (Sweden)

    Orlova Anzhela Manvelovna

    2011-11-01

    Full Text Available The description developed by the authors of structures and technologies production safety coatings based on glass fiber and paper, modified phenol-formaldehyde oligomers, which are possessed high physicochemical properties, durability and chemical durability, is presented.????????? ???????? ????????????? ???????? ???????? ? ?????????? ????????? ???????-????????? ?????????? ?? ?????? ???????????????? ????????????????????? ??????????? ???????????? ? ??????, ?????????? ???????? ??????-??????????? ??????????, ?????????????? ? ?????????? ??????????.

  14. 40 CFR 721.7220 - Polymer of substituted phenol, formaldehyde, epichlorohydrin, and disubstituted benzene.

    Science.gov (United States)

    2010-07-01

    ...2010-07-01 2010-07-01 false Polymer of substituted phenol, formaldehyde...Specific Chemical Substances § 721.7220 Polymer of substituted phenol, formaldehyde...chemical substance identified generically as polymer of substituted phenol,...

  15. Adhesion characteristics of phenol formaldehyde pre-preg oil palm stem veneers

    Directory of Open Access Journals (Sweden)

    Nor Hafizah Ab. Wahab

    2012-11-01

    Full Text Available The purpose of this study was to evaluate the adhesion properties of phenol formaldehyde-prepreg oil palm veneers that have potential for plywood manufacture. Phenol formaldehyde (PF resin of three different molecular weights (i.e. 600 (low, 2,000 (medium, and 5,000 (commercial were used to pre-treat the veneers. The veneers were soaked in each type of PF resin for 20 seconds, pressed between two rollers, and pre-cured in an oven maintained at 103 ± 2 °C for 24 hours. The volume percent gain (VPG, weight percent gain (WPG, pH, buffering capacity, and contact angle of the phenolic pre-preg veneers were determined. The bonding shear was also evaluated according to British Standard European Norm BS EN 314. The results show that veneers from both inner and outer layers treated with low molecular weight PF (LMwPF resin had significantly higher VPG and WPG compared to the other PF resins. The pH values of all of the veneers were slightly acidic (6.5 to 6.8 except for those that were treated with commercial molecular weight PF resin (7.8. A buffering capacity study revealed that untreated veneer had a greater resistance toward alkali, but was unstable under acidic conditions, while the phenolic pre-preg veneer behaved differently. This effect was more prominent as the molecular weight of the PF resin increased. An examination of the veneer surfaces demonstrated that phenolic treatment had increased the contact angle of the OPS veneer surfaces significantly. The bonding properties of plywood made from pre-preg palm veneers were found to be superior to those of commercial palm plywood.

  16. NMR study of the phenol-formaldehyde-water-methanol system

    International Nuclear Information System (INIS)

    A quantitative evaluation of the system phenol-formaldehyde-water-methanol was carried out using the method of 1H-NMR spectroscopy. The investigated region of the molar ratios phenol formaldehyde methanol varied within the range 1:29:9.6 to 1:0.2:0.07 and the spectra obtained were compared with the spectrum of water-methanol solution of formaldehyde. The system showed two groups of lines. Four simple singlets of linear polymers of the type C6H5O(CH2O)sub(n)H appeared in the region 5.20 to 5.35 delta whereas in the region 4.7 to 5.4 delta as many as eleven signals of the polymers HO(CH2O)sub(n)H and CH3O(CH2O)sub(n)H could be detected. Another three signals of polymers of the type C6H5O(CH2O)sub(n)CH3 appeared in the region 4.8 to 5.0 delta from the molar ratio phenol formaldehyde 1:2.2. (author)

  17. Production of plywood panels from Pinus taeda using veneers of differing densities and phenol-formaldehyde resin with high and low molecular weights / Produção de painéis compensados de Pinus taeda com lâminas de diferentes densidades e resina fenol-formaldeído com alto e baixo peso molecular

    Scientific Electronic Library Online (English)

    Graciela Ines Bolzon de, Muniz; Setsuo, Iwakiri; Lívia Cássia, Viana; Mário, Andrade; Cristiane, Weber; Vanessa Coelho, Almeida.

    2013-06-01

    Full Text Available Neste trabalho, objetivou-se avaliar a qualidade da colagem de painéis compensados de Pinus taeda, produzidos com resina fenol-formaldeido de alto e baixo peso molecular, e lâminas de três diferentes classes de densidades. O experimento foi organizado em seis tratamentos, e para cada tratamento fora [...] m produzidos três painéis (repetições). Os ensaios de resistência da linha de cola aos esforços de cisalhamento foram realizados após dois ciclos de fervura e após 24 horas de imersão em água fria. Determinou-se, também, a porcentagem de falhas na madeira. Os resultados indicaram que as classes de densidade são estatisticamente diferentes entre si. Entretanto, não houve diferença significativa entre os valores médios de resistência da linha de cola dos painéis produzidos com resina de alto e baixo peso molecular, tanto para os painéis submetidos aos dois ciclos de fervura, quanto para os submetidos ao ensaio após 24 horas em água fria. A interação entre as classes de densidade das lâminas e as formulações do adesivo, igualmente, não foi significativa. A resina de baixo peso molecular (BPM) e os compensados produzidos com as lâminas de maior densidade apresentou melhor comportamento, tanto para resistência quanto para a porcentagem de falha na madeira. Conclui-se que a qualidade de colagem dos painéis compensados de Pinus taeda produzidos com lâminas de densidades diferentes e com resinas fenólicas de alto e baixo peso molecular foi satisfatória. Todos os tratamentos atendem às exigências mínimas da norma européia EN 314-1/1993, que trata da qualidade da colagem de painéis compensados. Abstract in english This study aimed to evaluate the bonding quality of plywood panels from Pinus taeda using low and high molecular weight phenol-formaldehyde resin and veneers from three different density classes. The experiment consisted of six treatments, each of which produced three panels (replicates). Tests were [...] conducted to evaluate glue line strength to shear stress after two boiling cycles and after 24 hours of cold water immersion. Also determined was the percentage of defects in wood samples. Results indicated that the density classes being assessed differed statistically. However, no significant difference was found between panels produced with high and panels produced with low molecular weight resin as to the mean values of glue line strength, whether subjecting them to two boiling cycles or after 24 hours of cold water immersion. Interactions between different density classes and adhesive formulations were found not significant either. Low molecular weight resin (BPM) and panels produced with higher density veneers were found to have better behavior, regarding both bonding strength and percentage of defects. It was concluded that the bonding quality of plywood panels from Pinus taeda was satisfactory after using different densities of veneer and also high and low molecular weight phenolic resins. All treatments were found to comply with minimum requirements established in European standard EN 314-1/1993, which addresses bonding quality of plywood panels.

  18. Hierarchical activated mesoporous phenolic-resin-based carbons for supercapacitors.

    Science.gov (United States)

    Wang, Zhao; Zhou, Min; Chen, Hao; Jiang, Jingui; Guan, Shiyou

    2014-10-01

    A series of hierarchical activated mesoporous carbons (AMCs) were prepared by the activation of highly ordered, body-centered cubic mesoporous phenolic-resin-based carbon with KOH. The effect of the KOH/carbon-weight ratio on the textural properties and capacitive performance of the AMCs was investigated in detail. An AMC prepared with a KOH/carbon-weight ratio of 6:1 possessed the largest specific surface area (1118?m(2) g(-1)), with retention of the ordered mesoporous structure, and exhibited the highest specific capacitance of 260?F?g(-1) at a current density of 0.1?A?g(-1) in 1?M H2 SO4 aqueous electrolyte. This material also showed excellent rate capability (163?F?g(-1) retained at 20?A?g(-1)) and good long-term electrochemical stability. This superior capacitive performance could be attributed to a large specific surface area and an optimized micro-mesopore structure, which not only increased the effective specific surface area for charge storage but also provided a favorable pathway for efficient ion transport. PMID:25100552

  19. Radiation-chemical hardening of phenol-formaldehyde oligomers

    International Nuclear Information System (INIS)

    Radiation-chemical hardening of phenol formaldehyde oligomers of the resol type has been studied in the presence of furfural and diallylphthalate diluents. The samples have been hardened on an electron accelerator at an electron energy of 1.0-1.1 MeV and a dose rate of 2-3 Mrad/s. The kinetics of hardening has been studied on the yield of gel fraction within the range of absorbed doses from 7 to 400 Mrad. Radiation-chemical hardening of the studied compositions is activated with sensitizers, namely, amines, metal chlorides, and heterocyclic derivatives of metals. Furfural and diallylphthalate compositions are suitable for forming glass-fibre plastic items by the wet method and coatings under the action of ionizing radiations

  20. 21 CFR 177.2260 - Filters, resin-bonded.

    Science.gov (United States)

    2010-04-01

    ...employed in fiber finishing: BHT. Butyl (or isobutyl) palmitate or stearate. 2,5-Di-tert -butyl hydroquinone for use only in lubricant...h), and (i) of this section. Phenol-formaldehyde resins. Polyvinyl...

  1. Synthesis and characterization of ordered mesoporous anion-exchange inorganic/organic hybrid resins for radionuclide separation

    International Nuclear Information System (INIS)

    Ordered mesoporous anion-exchange hybrid resin materials were prepared by hydrolysis synthesis using the micellar template approach. The prepared samples were characterized via infrared spectroscopy, nitrogen sorption, and small-angle X-ray scattering. The uptakes of anionic thorium nitrate complexes by the new resins in 8 N nitric acid solutions were determined. The thorium loading capacity of the hybrid mesoporous silica functionalized with N-trimethoxysilylpropyl-N,N,N-tri-n-butylammonium is greater than that of the hybrid mesoporous silica functionalized with N-trimethoxylsilypropyl-N,N,N-trimethylammonium. The mesoporous hybrid anion-exchange resins were shown to be much more selective than a popular organic commercial anion-exchange resin

  2. Effects of copper nitrate addition on the pore property and lithium storage performance of hierarchical porous carbon nanosheets from phenolic resin

    International Nuclear Information System (INIS)

    Graphical abstract: - Abstract: Hierarchical porous carbon nanosheets (HPCS) were prepared by using thermoplastic phenolic formaldehyde resin as the carbon source and copper nitrate as the template precursor. The effects of Cu(NO3)2 loading content on the pore property and electrochemical performance of HPCS as anode material for lithium ion batteries were investigated. It was found that, with the addition of Cu(NO3)2, both the specific surface area and mesopore percentage increase. Correspondingly, the electrochemical performances of HPCS electrodes in terms of the specific capacity and rate performance improve for lithium ion batteries. The reasons were deduced and discussed from the view point of different pore size, especially the function of mesopores

  3. Phenol-formaldehyde intumescent coating composition and coating prepared therefrom

    Science.gov (United States)

    Salyer, Ival O. (Inventor); Fox, Bernard L. (Inventor)

    1986-01-01

    Intumescent coatings which form a thick, uniform, fine celled, low density foam upon exposure to a high intensity heat flux or flame are disclosed, the invention coatings comprise phenolic resin prepolymer containing a blowing agent and a nucleating agent; in the preferred embodiments the coatings also contains a silicone surfactant, the coatings are useful in thermal and fire protection systems.

  4. Synthesis of sulphonated mesoporous phenolic resins and their application in esterification and asymmetric aldol reactions

    International Nuclear Information System (INIS)

    Mesoporous phenolic resins were functionalized with sulphonic acid groups by four different types of sulphonation procedures: (i) direct sulphonation on the aromatic ring, (ii) alkyl sulphonation of the aromatic ring, and functionalizations of the phenolic hydroxyl surface by using an aryl silane, 2-(4-chlorosulphonylphenyl)ethyl trichlorosilane (iii) or a propyl silane, 3-mercaptopropyltrimethoxysilane (iv). The highest acidity loadings were obtained through direct sulphonation with fuming sulphuric acid (1.90 mmol H+ g?1) or chlorosulphonic acid (1.31 mmol H+ g?1) and these materials showed the highest conversion (97+ %) in Fischer esterification of acetic acid with propanol. However, the alkyl sulphonic groups, obtained through sulphonation procedure (ii) showed the highest stability in terms of maintenance of their acidity after use in consecutive catalytic runs or leaching treatments. This was demonstrated both through evaluation of the regenerated catalysts in a consecutive esterification run and during a leaching resistance test in aqueous medium. Moreover, the developed sulphonated mesoporous phenolic resins are presented as novel support for the non-covalent immobilization of an L-phenylalanine derived chiral diamine organocatalyst for asymmetric aldol reactions. The immobilization is established by an acid–base interaction between the sulphonic acid group and the amine function. The acidity and in particular the electronic withdrawing environment of the sulphonic acid groups influence enormously the catalytic performance of the non-covalent immobilized chiral diamine catalyst (aromatic > aliphatic). - Highlights: ? Different types of sulphonation procedures for mesoporous phenolic resins. ? Influence of acidity and electronic withdrawing environment. ? Novel support for non-covalent immobilization of chiral diamine catalyst. ? Catalytic performance in esterification and asymmetric aldol condensation. ? Demonstration of leaching resistance in aqueous medium

  5. Synthesis of sulphonated mesoporous phenolic resins and their application in esterification and asymmetric aldol reactions

    Energy Technology Data Exchange (ETDEWEB)

    Muylaert, Ilke [Department of Inorganic and Physical Chemistry, Ghent University, Center for Ordered Materials, Organometallics and Catalysis (COMOC), Krijgslaan 281-S3, 9000 Ghent (Belgium); Verberckmoes, An, E-mail: an.verberckmoes@hogent.be [Department of Inorganic and Physical Chemistry, Ghent University, Center for Ordered Materials, Organometallics and Catalysis (COMOC), Krijgslaan 281-S3, 9000 Ghent (Belgium); Associated Faculty of Applied Engineering Sciences, University College Ghent, Valentin Vaerwyckweg 1, 9000 Ghent (Belgium); Spileers, Jeremy [Associated Faculty of Applied Engineering Sciences, University College Ghent, Valentin Vaerwyckweg 1, 9000 Ghent (Belgium); Demuynck, Anneleen; Peng, Li; De Clippel, Filip; Sels, Bert [Katholieke Universiteit Leuven, Centre for Surface Chemistry and Catalysis (COK), Kasteelpark Arenberg 23, 3001 Heverlee (Belgium); Van Der Voort, Pascal, E-mail: pascal.vandervoort@ugent.be [Department of Inorganic and Physical Chemistry, Ghent University, Center for Ordered Materials, Organometallics and Catalysis (COMOC), Krijgslaan 281-S3, 9000 Ghent (Belgium)

    2013-02-15

    Mesoporous phenolic resins were functionalized with sulphonic acid groups by four different types of sulphonation procedures: (i) direct sulphonation on the aromatic ring, (ii) alkyl sulphonation of the aromatic ring, and functionalizations of the phenolic hydroxyl surface by using an aryl silane, 2-(4-chlorosulphonylphenyl)ethyl trichlorosilane (iii) or a propyl silane, 3-mercaptopropyltrimethoxysilane (iv). The highest acidity loadings were obtained through direct sulphonation with fuming sulphuric acid (1.90 mmol H{sup +} g{sup ?1}) or chlorosulphonic acid (1.31 mmol H{sup +} g{sup ?1}) and these materials showed the highest conversion (97+ %) in Fischer esterification of acetic acid with propanol. However, the alkyl sulphonic groups, obtained through sulphonation procedure (ii) showed the highest stability in terms of maintenance of their acidity after use in consecutive catalytic runs or leaching treatments. This was demonstrated both through evaluation of the regenerated catalysts in a consecutive esterification run and during a leaching resistance test in aqueous medium. Moreover, the developed sulphonated mesoporous phenolic resins are presented as novel support for the non-covalent immobilization of an L-phenylalanine derived chiral diamine organocatalyst for asymmetric aldol reactions. The immobilization is established by an acid–base interaction between the sulphonic acid group and the amine function. The acidity and in particular the electronic withdrawing environment of the sulphonic acid groups influence enormously the catalytic performance of the non-covalent immobilized chiral diamine catalyst (aromatic > aliphatic). - Highlights: ? Different types of sulphonation procedures for mesoporous phenolic resins. ? Influence of acidity and electronic withdrawing environment. ? Novel support for non-covalent immobilization of chiral diamine catalyst. ? Catalytic performance in esterification and asymmetric aldol condensation. ? Demonstration of leaching resistance in aqueous medium.

  6. Hydrothermal degradation of lignin: products analysis for phenol formaldehyde adhesive synthesis.

    Science.gov (United States)

    Yang, Sheng; Yuan, Tong-Qi; Li, Ming-Fei; Sun, Run-Cang

    2015-01-01

    Corncob lignin was treated with pressurized hot water in a cylindrical autoclave in current investigation. With the aim of investigating the effect of reaction temperature and retention time on the distribution of degradation products, the products were divided into five fractions including gas, volatile organic compounds, water-soluble oil, heavy oil, and solid residue. It was found that hydrothermal degradation of corncob lignin in pressurized hot water produced a large amount of phenolic compounds with lower molecular weight than the raw lignin. Some phenolic and benzene derivatives monomers such as vanillin, 2-methoxy-phenol, 2-ethyl-phenol, p-xylene, and 1, 3-dimethyl-benzene were also identified in the degradation products. The products were further analyzed by GC-MS, GPC, 2D-HSQC, and (31)P-NMR to investigate their suitability for partial incorporation into phenol formaldehyde adhesive as a substitution of phenol. The results indicated that the reaction temperature had more effect on the products distribution than the retention time. The optimal condition for heavy oil production appeared at 290 °C with retention time 0 min. The compounds of heavy oil had more active sites than the raw lignin, suggesting that the heavy oil obtained from hydrothermal degradation of lignin is a promising material for phenol formaldehyde adhesive synthesis. PMID:25109457

  7. Stabilizing diamond surface conductivity by phenol-formaldehyde and acrylate resins.

    Czech Academy of Sciences Publication Activity Database

    Rezek, Bohuslav; Kozak, Halyna; Kromka, Alexander

    2009-01-01

    Ro?. 517, ?. 13 (2009), s. 3738-3741. ISSN 0040-6090 R&D Projects: GA AV ?R KAN400100701; GA MŠk LC510 Institutional research plan: CEZ:AV0Z10100521 Keywords : diamond * surface conductivity * polymer * passivation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.727, year: 2009

  8. Relation between Mechanical Properties and Pyrolysis Temperature of Phenol Formaldehyde Resin for Gas Separation Membranes.

    Czech Academy of Sciences Publication Activity Database

    Šupová, Monika; Svítilová, Jaroslava; Chlup, Zden?k; ?erný, Martin; Weishauptová, Zuzana; Suchý, Tomáš; Machovi?, Vladimír; Sucharda, Zbyn?k; Žaloudková, Margit

    2012-01-01

    Ro?. 56, ?. 1 (2012), s. 40-49. ISSN 0862-5468 R&D Projects: GA ?R GA203/09/1327 Institutional research plan: CEZ:AV0Z30460519; CEZ:AV0Z20410507 Keywords : glassy carbon * membranes * mechanical properties Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.418, year: 2012 http://www.ceramics-silikaty.cz/2012/pdf/2012_01_40.pdf

  9. Preparation and thermal properties of mesoporous silica/phenolic resin nanocomposites via in situ polymerization

    Directory of Open Access Journals (Sweden)

    J. Lv

    2012-10-01

    Full Text Available In order to enhance the adhesion between inorganic particles and polymer matrix, in this paper, the mesoporous silica SBA-15 material was synthesized by the sol-gel method. The surface of SBA-15 was modified using ?-glycidyloxypropyltrimethoxysilane (GOTMS as a coupling agent, and then mesoporous silica/phenolic resin (SBA-15/PF nanocomposites were prepared via in situ polymerization. The structural parameters and physical properties of SBA-15, SBA-15-GOTMS (SBA-15 surface treated using GOTMS as coupling agents and E-SBA-15/PF (SBA-15/PF nanocomposites extracted using ethanol as solvent were characterized by X-ray diffraction (XRD, N2 adsorption-desorption, Fourier transform infrared spectroscopy (FTIR, scanning electron microscopy (SEM, transmission electron microscopy (TEM and thermogravimetric analysis (TGA. The thermal properties of the nanocomposites were studied by differential scanning calorimetry (DSC and thermogravimetric analysis (TGA. The results demonstrated that the GOTMS were successfully grafted onto the surface of SBA-15, and chemical bonds between PF and SBA-15-GOTMS were formed after in situ polymerization. In addition, it is found that the in situ polymerization method has great effects on the textural parameters of SBA-15. The results also showed that the glass transition temperatures and thermal stability of the PF nanocomposites were obviously enhanced as compared with the pure PF at silica contents between 1–3 wt%, due to the uniform dispersion of the modified SBA-15 in the matrix.

  10. Challenges in Fabrication of Mesoporous Carbon Films with Ordered Cylindrical Pores via Phenolic Oligomer Self-Assembly with Triblock Copolymers

    Energy Technology Data Exchange (ETDEWEB)

    Song, Lingyan; Feng, Dan; Fredin, Nathaniel J.; Yager, Kevin G.; Jones, Ronald L.; Wu, Quanyan; Zhao, Dongyuan; Vogt, Bryan D. (On Semi); (AZU); (NIST); (Fudan)

    2010-06-22

    Mesoporous phenol formaldehyde (PF) polymer resin and carbon films are prepared by a solution self-assembly of PF oligomers with amphiphilic triblock copolymers. After thermopolymerization of the PF to cross-link the network, the films show an ordered morphology as determined by X-ray diffraction and grazing incidence small-angle X-ray scattering (GISAXS). Our results show that the amphiphilic triblock copolymer template greatly influences the stability of the final porous mesostructures. The pyrolysis of the two-dimensional (2-D) hexagonal films with p6mm symmetry templated by Pluronic F127 yields a disordered porous structure following the template removal. Conversely, films templated by Pluronic P123 can exhibit well-ordered cylindrical pores after the template removal, but the solution composition range to yield ordered cylindrical mesopores is significantly reduced (nearly 70%) for thin films in comparison to bulk powders. We propose two dominant difficulties in fabricating well-ordered cylindrical mesopores in films: first, the stress from contraction during the pyrolysis can lead to a collapse of the mesostructure if the wall thickness is insufficient, and second, the surface wetting behavior in thin films leads to a small compositional range.

  11. Influence of nitrogen-containing phenol-formaldehyde oligomer on sorptive properties of macroporous polymer impregnated with tributylphosphate

    International Nuclear Information System (INIS)

    Distribution of scandium(3), zirconium(4), niobium(5), molybdenum(6), cadmium(2), indium(3), tellurium(4) and uranium(6) between HCl aqueous solutions and macroporous polymer sorbent impregnated by a mixture of nitrogen-containing phenol-formaldehyde resol oligomer (Yarrezin B) and tributylphosphate is studied. It is ascertained that increase in distribution factors of the complexes extracted by the impregnated sorbent compared to solvent extraction stems from the absence of extractant association in the sorbent phase

  12. Mesoporous carbon adsorbents from melamine-formaldehyde resin using nanocasting technique for CO2 adsorption.

    Science.gov (United States)

    Goel, Chitrakshi; Bhunia, Haripada; Bajpai, Pramod K

    2015-06-01

    Mesoporous carbon adsorbents, having high nitrogen content, were synthesized via nanocasting technique with melamine-formaldehyde resin as precursor and mesoporous silica as template. A series of adsorbents were prepared by varying the carbonization temperature from 400 to 700°C. Adsorbents were characterized thoroughly by nitrogen sorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), elemental (CHN) analysis, Fourier transform infrared (FTIR) spectroscopy and Boehm titration. Carbonization temperature controlled the properties of the synthesized adsorbents ranging from surface area to their nitrogen content, which play major role in their application as adsorbents for CO2 capture. The nanostructure of these materials was confirmed by XRD and TEM. Their nitrogen content decreased with an increase in carbonization temperature while other properties like surface area, pore volume, thermal stability and surface basicity increased with the carbonization temperature. These materials were evaluated for CO2 adsorption by fixed-bed column adsorption experiments. Adsorbent synthesized at 700°C was found to have the highest surface area and surface basicity along with maximum CO2 adsorption capacity among the synthesized adsorbents. Breakthrough time and CO2 equilibrium adsorption capacity were investigated from the breakthrough curves and were found to decrease with increase in adsorption temperature. Adsorption process for carbon adsorbent-CO2 system was found to be reversible with stable adsorption capacity over four consecutive adsorption-desorption cycles. From three isotherm models used to analyze the equilibrium data, Temkin isotherm model presented a nearly perfect fit implying the heterogeneous adsorbent surface. PMID:26040750

  13. Studies on Glass Reinforced Epoxy Resin Using Vulkadur- A as Crosslinking Agent both in Presence and Absence of Carbon Black and other Non black Fillers

    Directory of Open Access Journals (Sweden)

    T. K. Ghosh

    1974-04-01

    Full Text Available Epoxy resin can be reinforced with glass (fabric form in presence of Vulkadur-A, a phenol formaldehyde resin containing a hardening agent. Overall enhancement in mechanical properties has been found stocks cured with Vulkadur-A containing 2.5 parts of carbon black as filler.

  14. Phenolic resins a century of progress

    CERN Document Server

    Pilato, Louis

    2010-01-01

    The legacy of Leo Hendrik Baekeland and his development of phenol formal- hyde resins are recognized as the cornerstone of the Plastics Industry in the early twentieth century, and phenolic resins continue to ?ourish after a century of robust growth. On July 13, 1907, Baekeland ?led his "heat and pressure" patent related to the processing of phenol formaldehyde resins and identi?ed their unique utility in a plethora of applications. The year 2010 marks the Centennial Year of the prod- tion of phenolic resins by Leo Baekeland. In 1910, Baekeland formed Bakelite GmbH and launched the manufacture

  15. Investigation of utilization of process of polyethylene waste of low density for creation of competitive materials with application of phenol formaldehyde oligomers

    International Nuclear Information System (INIS)

    Full text: The possibility of the utilization of low density polyethylene wastes by means of their modification with phenol formaldehyde oligomers (Ph FO) and PhFO with the thiourathenes has been investigation. Theology properties of the investigated systems showed that the obtained compositions can be able to be processed by the ordinary methods such as extrusion and casting

  16. Hydrogen Bonding-Mediated Microphase Separation during the Formation of Mesoporous Novolac-Type Phenolic Resin Templated by the Triblock Copolymer, PEO-b-PPO-b-PEO

    Directory of Open Access Journals (Sweden)

    Wei-Cheng Chu

    2013-11-01

    Full Text Available After blending the triblock copolymer, poly(ethylene oxide-b-propylene oxide-b-ethylene oxide (PEO-b-PPO-b-PEO with novolac-type phenolic resin, Fourier transform infrared spectroscopy revealed that the ether groups of the PEO block were stronger hydrogen bond acceptors for the OH groups of phenolic resin than were the ether groups of the PPO block. Thermal curing with hexamethylenetetramine as the curing agent resulted in the triblock copolymer being incorporated into the phenolic resin, forming a nanostructure through a mechanism involving reaction-induced microphase separation. Mild pyrolysis conditions led to the removal of the PEO-b-PPO-b-PEO triblock copolymer and formation of mesoporous phenolic resin. This approach provided a variety of composition-dependent nanostructures, including disordered wormlike, body-centered-cubic spherical and disorder micelles. The regular mesoporous novolac-type phenolic resin was formed only at a phenolic content of 40–60 wt %, the result of an intriguing balance of hydrogen bonding interactions among the phenolic resin and the PEO and PPO segments of the triblock copolymer.

  17. Characterization of alkaline lignins for use in penol-formaldehyde and epoxy resins

    OpenAIRE

    El Mansouri, Nour-Eddine; Yuan, Qiaolong; Huang, Farong

    2011-01-01

    Besides polyurethanes and polyesters, phenolic and epoxy resins are the most prominent applications for technical lignins in thermosetting materials. To evaluate the potential application of lignin raw materials in phenol formaldehyde and epoxy resins, three types of alkaline lignins were characterized in terms of their structures and thermal properties. The lignin samples analyzed were kraft lignin (LIG-1), soda–rice straw lignin (LIG-2), and soda-wheat straw lignin (LIG-3). FTIR and 1H-NMR ...

  18. USE OF LIGNIN SEPARATED FROM BIO-OIL IN ORIENTED STRAND BOARD BINDER PHENOL-FORMALDEHYDE RESINS

    OpenAIRE

    Badamkhand Sukhbaatar; Philip H. Steele; Moon G. Kim

    2009-01-01

    Bio-oil produced from fast pyrolysis of biomass has been investigated as a renewable fuel and as a source of industrial chemicals. The lignin fraction of bio-oil produced from wood in our fast pyrolysis reactor was separated by using only water and methanol with a 25% yield based on bio-oil weight. This separation procedure appears to be of lower cost than the reported extraction procedure using ethyl acetate as solvent. The isolated pyrolytic lignin was smoothly incorporated into phenol-for...

  19. Efficient removal of aniline by a water-compatible microporous and mesoporous hyper-cross-linked resin and XAD-4 resin: A comparative study

    Science.gov (United States)

    Xiao, Guqing; Long, Liping

    2012-06-01

    A novel water-compatible microporous and mesoporous hyper-cross-linked resin modified with phenolic hydroxyl group (named as GQ-03) was synthesized to remove aniline in aqueous solution as compared with XAD-4. The maximum adsorption capacity of GQ-03 emerged at the molecular state for both aniline and p-cresol while the pH dependency trend of aniline adsorbed onto XAD-4 was accordant with the dissociation curve of aniline. The ionic strength influenced the adsorption obviously. The pseudo-first-order rate equation could describe the adsorption process of aniline onto GQ-03 in two stages while this equation could characterize the entire adsorption process of XAD-4. The adsorption isotherms could be correlated to the Freundlich model, higher KF and n values for GQ-03 than XAD-4. The breakthrough capacity and the total adsorption capacity of GQ-03 and XAD-4 was up to 47.2 mg mL-1 and 28.3 mg mL-1, 271.7 mg mL-1 and 115.6 mg mL-1, respectively. The size matching between the pore diameter of GQ-03 and the molecular size of aniline, and hydrogen bonding between GQ-03 and aniline resulted in the larger adsorption capacity.

  20. Effects of phenol-formaldehyde / isocyanate hybrid adhesives on properties of oriented strand lumber (OSL from rubberwood waste

    Directory of Open Access Journals (Sweden)

    Wanchart Preechatiwong

    2007-09-01

    Full Text Available The objective of this research project was to study the effects of hybrid adhesives of Phenol-Formaldehyde (PF and Polymeric Diphenylmethane Diisocyanate (MDI on the properties of Oriented Strand Lumber (OSL to determine the optimal ratio of both adhesives. The results showed that OSL formed by pure adhesive or hybrid adhesives (3 blends: 25:75, 50:50 and 75:25 had properties that pass the CSA O437.1 standards, such as (1 modulus of rupture, (2 modulus of elasticity, and (3 internal bond strength. However, the thickness swelling and bond durability of OSL formed by pure MDI failed to pass the standards, while those formed by pure PF or hybrid adhesives passed. Among the three blends of adhesives, the blend 75:25 (PF: MDI gave the best properties while ratio of 50:50 gave the worst properties, especially internal bond strength due to the phase separation of both adhesives. In addition, the modulus of rupture and modulus of elasticity in the "edgewise" direction were higher than those in the "flatwise" direction. In the edgewise direction, load is transferred in the direction of width of strand that is large while in the flatwise direction, load is transferred in the direction of thickness of strand which is small.

  1. Chemical derivation to enhance the chemical/oxidative stability of resorcinol-formaldehyde (R-F) resin

    Energy Technology Data Exchange (ETDEWEB)

    Hubler, T.L.; Shaw, W.J.; Brown, G.N.; Linehan, J.C.; Franz, J.A.; Hart, T.R.; Hogan, M.O.

    1996-09-01

    Tank wastes at Hanford and SRS contain highly alkaline supernate solutions of conc. Na, K nitrates with large amounts of {sup 137}Cs. It is desirable to remove and concentrate the highly radioactive fraction for vitrification. One candidate ion exchange material for removing the radiocesium is R-F resin. This report summarizes studies into synthesis and characterization of 4-derivatized R-F resins prepared in pursuit of more chemically/oxidatively robust resin. 85% 4-fluororesorcinol/15% phenol formaldehyde resin appears to have good stability in alkaline solution, although there may be some nucleophilic displacement reaction during synthesis; further studies are needed.

  2. Formaldehyde resins in building materials. December 1973-October 1989 (Citations from the Rubber and Plastics Research Association data base). Report for December 1973-October 1989

    Energy Technology Data Exchange (ETDEWEB)

    1989-12-01

    This bibliography contains citations concerning regulations, standards, safety, and applications of formaldehyde-resin compositions in the building industry. Urea formaldehyde is emphasized; however, phenol formaldehyde and melamine formaldehyde are also considered for such applications as thermal insulation, bonding agents, and composite construction materials. Ramifications of state and federal legislation, substitute materials, and toxicology studies are included. (This updated bibliography contains 376 citations, 46 of which are new entries to the previous edition.)

  3. Microporosity development in phenolic resin-based mesoporous carbons for enhancing CO2 adsorption at ambient conditions

    Science.gov (United States)

    Choma, Jerzy; Jedynak, Katarzyna; Fahrenholz, Weronika; Ludwinowicz, Jowita; Jaroniec, Mietek

    2014-01-01

    Soft-templating method was used to prepare mesoporous carbons. The synthesis in the presence of hydrochloric and citric acids involved resorcinol and formaldehyde as carbon precursors and triblock copolymer Pluronic F127 as a template. The as-synthesized samples underwent carbonization in flowing nitrogen at various temperatures; namely 600 °C, 700 °C and 800 °C. Two routes were used to develop microporosity in the mesoporous carbons studied. The first one involved introduction of tetraethyl orthosilicate to the reaction system. After silica dissolution with NaOH, an increase in microporosity was observed. The second method, chemical activation with KOH at 700 °C, was explored as an alternative approach to create microporosity. It is noteworthy that the TEOS addition not only led to the development of microporosity but also to some improvement of mesoporosity. The post-synthesis KOH activation resulted in more significant increase in the microporosity as compared to the samples obtained by TEOS-assisted synthesis. The mesopore volume was somewhat lower for activated carbons as compared to that in mesoporous carbons. Both methods resulted in micro-mesoporous carbons with good adsorption properties; for instance, in the case of carbons prepared in the presence of TEOS, the best sample exhibited BET surface area of 1463 m2/g and the total pore volume of 1.31 cm3/g. For the KOH activated carbons the best adsorption parameters were as follows: the specific surface area = 1906 m2/g, and the total pore volume = 0.98 cm3/g. Both procedures used for microporosity development afforded carbons with good adsorption properties that can be useful for applications such as CO2 adsorption, air and water purification.

  4. EPICOR-II resin degradation results from first resin samples of PF-8 and PF-20

    International Nuclear Information System (INIS)

    The 28 March 1979 accident at Three Mile Island Unit 2 released approximately 560,000 gallons of contaminated water to the Auxiliary and Fuel Handling Buildings. The water was decontaminated using a demineralization system called EPICOR-II developed by Epicor, Inc. The Low-Level Waste Data Base Development - EPICOR-II Resin/Liner Investigation Project is studying the chemical and physical conditions of the synthetic ion exchange resins found in several EPICOR-II prefilters. This report summarizes results and analyses of the first sampling of ion exchange resins from EPICOR-II prefilters PE-8 and -20. Results are compared with baseline data from tests performed on unirradiated Epicor, Inc. resins to determine if degradation has occurred due to the high internal radiation dose received by the EPICOR-II resins. Results also are compared with recent findings on resin degradation by Battelle Columbus Laboratories and Brookhaven National Laboratory. Analyses comparing test results of resins from EPICOR-II prefilters PF-8 and -20 with unirradiated resins obtained from Epicor, Inc. show resin degradation has occurred in some of the EPICOR-II resins examined. The mechanism of degradation is compared with work of other researchers and is consistent with their findings. The strong acid cation resins (divinylbenzene, styrene base structure) are losing effective cross-linking along with scission of functional groups and are experiencing first an increase and eventually a decrease in total exchange capacity as the absorbed radiation dose increases. The phenolic cation resins (phenol-formaldehyde base structure) show a loss of effective cross-linking and oxidation of the polymer chain. Analyses of resins removed from EPICOR-II prefilters PF-8 and -20 over the next several years should show a further increase in degradation

  5. Weather ability studies of phenolic resin coated woods and glass fiber reinforced laminates

    International Nuclear Information System (INIS)

    Phenolic resins have made a major breakthrough in the field of high technology in 80's. These are now active participants of high tech' areas ranging from electronics, computers, communication, outer space, aerospace, advanced materials, bio materials and technology. A phenol - formaldehyde (1:1.5) resin having resin content of 70% synthesized in the laboratory has been applied for wood coating and reinforcing glass fiber. The weatherability and solvent resistance of these items have been studied and results discussed keeping in view the envisaged application for structural materials and chemical equipment. The toxic materials released during contact with solvents for chemical applications and during degradation general have been monitored. The results are discussed with reference to environmental pollution due to these resins and their composites under different conditions. (authors)

  6. Qualidade de compensados fabricados com adesivos à base de Tanino-Formaldeído de Pinus oocarpa e Fenol-Formaldeído / Quality of plywood manufactured with Tannin-formaldehyde from Pinus oocarpa plus Phenol-Formaldehyde-based adhesive

    Scientific Electronic Library Online (English)

    Bruno Couto da, Silva; Michel Cardoso, Vieira; Gisely de Lima, Oliveira; Fabricio Gomes, Gonçalves; Nayara Dorigon, Rodrigues; Roberto Carlos Costa, Lelis; Setsuo, Iwakiri.

    2012-12-01

    Full Text Available Este trabalho teve por objetivo avaliar a qualidade de compensados fabricados com adesivos à base de taninos da casca de Pinus oocarpa e Fenol-Formaldeído (FF). O plano experimental foi composto de quatro tratamentos: Tanino-Formaldeído (TF); Fenol-Formaldeído (FF); FF + 10%TF (90:10), e FF + 20% TF [...] (80:20). Os painéis foram avaliados nos seguintes aspectos: resistência à flexão estática (MOR); ensaio de cisalhamento na linha de cola; densidade e recuperação em espessura (RE); inchamento mais recuperação em espessura (IR), e absorção em água (AA). Os resultados mostraram que é possível substituir o adesivo FF por tanino em até 20% sem alterar os valores de MOR paralelo e perpendicular à grã das lâminas externas dos compensados. Para obtenção de maior estabilidade dimensional dos compensados fabricados com adesivo à base de tanino, torna-se necessária a adição de parafina. Os resultados mostraram também que não houve diferença significativa nos valores de resistência ao cisalhamento dos compensados para os diferentes tratamentos. Abstract in english The aim of this paper was to evaluate the quality of plywood panels manufactured with tannin-based adhesives extracted from the bark of Pinus oocarpa and Phenol-Formaldehyde. The experimental plan was composed of four treatments: Tannin-formaldehyde (TF), Phenol-formaldehyde (FF), FF + 10%TF (90:10) [...] and FF + 20%TF (80:20). The quality of plywood panels was evaluated by the static bending (MOR), bonding line shear test of the adhesive, and dimensional stability: thickness swelling, recovery of thickness and water absorption. Results showed that it is possible to substitute Phenol-Formaldehyde adhesive by tannin up to 20% without changing MOR parallel and MOR perpendicular to the grain of the the panels. In order to obtain higher values of physical properties of plywood made with tannin from bark of Pinus oocarpa, it is necessary to add paraffin. Results showed that there was no significant difference in values of shear strength for the different treatments.

  7. Modeling the Effects of Velocity, Spin, Frictional Coefficient, and Impact Angle on Deflection Angle in Near-elastic Collisions of Phenolic Resin Spheres

    CERN Document Server

    Crown, S C

    2004-01-01

    A simple model is outlined to describe the collision of cast phenol-formaldehyde resin spheres such as the balls used in the parlor game of pocket billiards, based in part on the famous analysis of elastic collisions developed by Heinrich Hertz over 100 years ago. The analysis treats the normal and tangential components of the initial sphere's velocity independently as it collides with a stationary identical second sphere. The collective effects of these and other parameters on the trajectory of the second sphere are provided in the conclusions.

  8. Use of gold and silver standards based on phenol-formalde-hyde resin in assay-activation analysis of geological samples

    International Nuclear Information System (INIS)

    Using standards on phenol-formaldehyde resin base for assaying-activation analysis of geological specimens for gold and silver has bee the advantage of uniformly distributing Au and Ag in spesimens and possible preparing tablets of practically any form or size. The validity and accuracy of these standards have been studied for the cases of short irradiation. Conventional point standards were used as reference standards. The experiments carried out have shown that tablet resol standards are suitable for a mass assaying-activation analysis for gold and silver at practically any concentrations

  9. Large-scale synthesis of onion-like carbon nanoparticles by carbonization of phenolic resin

    International Nuclear Information System (INIS)

    Onion-like carbon nanoparticles have been synthesized on a large scale by carbonization of phenolic-formaldehyde resin at 1000 oC with the aid of ferric nitrate (FN). The effects of FN loading content on the yield, morphology and structure of carbonized products were investigated using transmission electron microscopy (TEM), high-resolution TEM and X-ray diffraction. It was found that the onion-like carbon nanoparticles, which had a narrow size distribution ranging from 30 to 50 nm, were composed mainly of quasi-spherically concentric shells of well-aligned graphene layers with interlayer spacing of 0.336 nm. Based on the results of the investigation, the formation mechanism of onion-like carbon nanoparticles was also discussed

  10. Lignocellulosic composites from brazilian giant bamboo (Guadua magna) Part 1: Properties of resin bonded particleboards

    Scientific Electronic Library Online (English)

    Larissa M, Arruda; Cláudio H. S, Del Menezzi; Divino E, Teixeira; Priscila C, de Araújo.

    Full Text Available This experiment evaluated the utilization of the recently identified Brazilian giant bamboo, Guadua magna (Londoño & Filg.) to manufacture medium density particleboard. Four board types were tested: two of them exclusively with particles of bamboo and two in a mixture of bamboo with Pinus taeda wood [...] particles. The target density of the panels was 0.65 g/cm³ for all treatments. The particleboards were bonded using 8% content of urea-formaldehyde (UF) and phenol-formaldehyde (PF) resins, based on dry weight mat. Mechanical, physical and nondestructive properties of the panels were assessed. The particleboards produced with PF showed better dimensional stability than UF particleboards. The addition of wood particles improved the mechanical properties of E M, fM and IB. The flexural properties of the panels (E M, fM) could be modeled using either E Md or density and the models fitted presented high predictability (>66%).

  11. Synthesis, structural characterization, and performance evaluation of resorcinol-formaldehyde (R-F) ion-exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    Hubler, T.L.; Franz, J.A.; Shaw, W.J.; Bryan, S.A.; Hallen, R.T.; Brown, G.N.; Bray, L.A.; Linehan, J.C.

    1995-08-01

    The 177 underground storage tanks at the DOE`s Hanford Site contain an estimated 180 million tons of high-level radioactive wastes. It is desirable to remove and concentrate the highly radioactive fraction of the tank wastes for vitrification. Resorcinol-formaldehyde (R-F) resin, an organic ion-exchange resin with high selectivity and capacity for the cesium ion, which is a candidate ion-exchange material for use in remediation of tank wastes. The report includes information on the structure/function analysis of R-F resin and the synthetic factors that affect performance of the resin. CS-100, a commercially available phenol-formaldehyde (P-F) resin, and currently the baseline ion-exchanger for removal of cesium ion at Hanford, is compared with the R-F resin. The primary structural unit of the R-F resin was determined to consist of a 1,2,3,4-tetrasubstituted resorcinol ring unit while CS-100, was composed mainly of a 1,2,4-trisubstituted ring. CS-100 shows the presence of phenoxy-ether groups, and this may account for the much lower decontamination factor of CS-100 for cesium ion. Curing temperatures for the R-F resin were found to be optimal at 105--130C. At lower temperatures, insufficient curing, hence crosslinking, of the polymer resin occurs and selectivity for cesium drops. Curing at elevated temperatures leads to chemical degradation. Optimal particle size for R-F resin is in the range of 20--50 mesh-sized particles. R-F resin undergoes chemical degradation or oxidation which destroys ion-exchange sites. The ion-exchange sites (hydroxyl groups) are converted to quinones and ketones. CS-100, though it has much lower performance for cesium ion-exchange, is significantly more chemically stable than R-F resin. To gamma radiation, CS-100 is more radiolytically stable than R-F resin.

  12. Physico-mechanical properties of plywood bonded by nano cupric oxide (CuO) modified pf resins against subterranean termites

    Scientific Electronic Library Online (English)

    Wei, Gao; Guanben, Du.

    Full Text Available Nano CuO and alkane surfactant modified phenol Formaldehyde (PF) resins were applied to manufacture plywood, and physical and mechanical properties, such as shear strength, tensile property, modulus of rupture (MOR), modulus of elasticity (MOE), as well as termite resistance were evaluated. The resu [...] lt showed that the combination of nano CuO and alkane surfactantplayed different effect on tensile strength, and especially on shear strength as evaluated at different test conditions. But it was confirmed to improve the water resistance of treated plywood specimens. The introduction of nano CuO and surfactant did not influence the flexural properties significantly by statistically. The result of termite tests indicated that the weight loss decreases gradually from 31,12% to less than 10,37%, and the mortality increases from 32,61% to higher than 86,35%. And the AWPA rating also rises from 4 (very severe attack) to 7 (moderate attack).

  13. Physico-mechanical properties of plywood bonded by nano cupric oxide (CuO) modified pf resins against subterranean termites

    Scientific Electronic Library Online (English)

    Wei, Gao; Guanben, Du.

    2015-01-01

    Full Text Available Nano CuO and alkane surfactant modified phenol Formaldehyde (PF) resins were applied to manufacture plywood, and physical and mechanical properties, such as shear strength, tensile property, modulus of rupture (MOR), modulus of elasticity (MOE), as well as termite resistance were evaluated. The resu [...] lt showed that the combination of nano CuO and alkane surfactantplayed different effect on tensile strength, and especially on shear strength as evaluated at different test conditions. But it was confirmed to improve the water resistance of treated plywood specimens. The introduction of nano CuO and surfactant did not influence the flexural properties significantly by statistically. The result of termite tests indicated that the weight loss decreases gradually from 31,12% to less than 10,37%, and the mortality increases from 32,61% to higher than 86,35%. And the AWPA rating also rises from 4 (very severe attack) to 7 (moderate attack).

  14. Multifunctional mesoporous silica catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Victor Shang-Yi; Tsai, Chih-Hsiang; Chen, Hung-Ting; Pruski, Marek; Kobayashi, Takeshi

    2015-03-31

    The present invention provides bifunctional silica mesoporous materials, including mesoporous silica nanoparticles ("MSN"), having pores modified with diarylammonium triflate and perfluoroaryl moieties, that are useful for the acid-catalyzed esterification of organic acids with organic alcohols.

  15. Fractal of mesoporous silica

    International Nuclear Information System (INIS)

    Mesoporous silica has potential use in catalytic, adsorbent and separate applications. Hybridization with organic groups can improve the surface property of mesoporous silica. In this paper the small angle X-ray scattering technique using synchrotron radiation was used to study fractal structure of mesoporous materials. The results showed that these materials possess both surface fractal and pore fractal structure. Variation of fractal dimension with the material preparation condition was also discussed

  16. Hypercrosslinked phenolic polymers with well-developed mesoporous frameworks.

    Science.gov (United States)

    Zhang, Jinshui; Qiao, Zhen-An; Mahurin, Shannon M; Jiang, Xueguang; Chai, Song-Hai; Lu, Hanfeng; Nelson, Kimberly; Dai, Sheng

    2015-04-01

    A soft chemistry synthetic strategy based on a Friedel-Crafts alkylation reaction is developed for the textural engineering of phenolic resin (PR) with a robust mesoporous framework to avoid serious framework shrinkage and maximize retention of organic functional moieties. By taking advantage of the structural benefits of molecular bridges, the resultant sample maintains a bimodal micro-mesoporous architecture with well-preserved organic functional groups, which is effective for carbon capture. Moreover, this soft chemistry synthetic protocol can be further extended to nanotexture other arene-based polymers with robust frameworks. PMID:25683637

  17. Hypercrosslinked Phenolic Polymers with Well Developed Mesoporous Frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jinshui [ORNL; Qiao, Zhenan [ORNL; Mahurin, Shannon Mark [ORNL; Jiang, Xueguang [ORNL; Chai, Songhai [ORNL; Lu, Hanfeng [ORNL; Nelson, Kimberly M [ORNL; Dai, Sheng [ORNL

    2015-01-01

    A soft chemistry synthetic strategy based on a Friedel Crafts alkylation reaction is developed for the textural engineering of phenolic resin (PR) with a robust mesoporous framework to avoid serious framework shrinkage and maximize retention of organic functional moieties. By taking advantage of the structural benefits of molecular bridges, the resultant sample maintains a bimodal micro-mesoporous architecture with well-preserved organic functional groups, which is effective for carbon capture. Moreover, this soft chemistry synthetic protocol can be further extended to nanotexture other aromatic-based polymers with robust frameworks.

  18. Enhancing the Properties of Low Density Hardwood Dyera costulata Through Impregnation with Phenolic Resin Admixed with Formaldehyde Scavenger

    Directory of Open Access Journals (Sweden)

    M.T. Paridah

    2011-01-01

    Full Text Available The formaldehyde emission, properties and decay durability of Dyera constulata wood, impregnated with low molecular weight phenol formaldehyde (LmwPF resin mixed with urea were investigated. The air-dry wood was impregnated with 20-40% LmwPF (Mw 600 mixed separately with urea (30% based on solid PF, partially cured at 60C for 30 min and subsequently heated at 150C for 60-120 min. The treatments had successfully reduced the formaldehyde emission (FE of the impreg and the degrees of reduction depend on curing time. Statistical analyses showed that the concentration of resin affected the density, stiffness, water absorption and thickness swelling, while the curing time affected the density, polymer loading, water absorption and thickness swelling. Impreg product had higher MOR, MOE and dimensional stability compared to the untreated wood. The treatments rendered the impreg product with approximately 20% in anti-swelling efficiency and had also changed the wood into highly resistant to fungal decay.

  19. Fabrication and Characterization of Inorganic Silver and Palladium Nanostructures within Hexagonal Cylindrical Channels of Mesoporous Carbon

    OpenAIRE

    Jheng-Guang Li; Cheng-Ying Tsai; Shiao-Wei Kuo

    2014-01-01

    In this study, we prepared a mesoporous carbon with hexagonally packed mesopores through evaporation-induced self-assembly (EISA)—with the diblock copolymer poly(ethylene oxide-b-?-caprolactone) (PEO-b-PCL) as the template (EO114CL84), phenolic resin as the carbon precursor, hexamethylenetetramine (HMTA) as the curing agent, and star octakis-PEO-functionalized polyhedral oligomeric silsesquioxane (PEO–POSS) as the structure modifier—and subsequent carbonization. We then took the cylindrical m...

  20. Composite material based on an ablative phenolic resin and carbon fibers

    Directory of Open Access Journals (Sweden)

    DIMKO DIMESKI

    2009-04-01

    Full Text Available In this study, a technological procedure for the production of a molding compound based on short carbon fibers and an ablative phenol–formaldehyde resin for high temperature application was optimized. The starting raw materials were characterized and molding compounds with different fiber/matrix ratios and different fiber lengths were obtained. From the different laboratory samples, molded parts were made by thermocompression. The basic mechanical and thermal properties of the composites were determined. From the obtained results, the optimal fiber/matrix ratio was determined for a production of molding compound for high temperature application. The molding process of the composite material was optimized and all the parameters for good mechanical properties and high thermal stability of the composite were obtained. Optimization of the composite molding process was performed by the application of a numerical method for a planned experiment, i.e., a full three-factorial experimental design with variance of all three parameters (fiber length, temperature and time of the press cycle on two levels. The obtained mechanical properties (flexural strength: 247 MPa, modulus: 27.6 GPa, impact resistance: 110 (for test moldings 10 mm´10 mm and 91 kJ/m2 (for test moldings 15 mm´15 mm justified the application of this composite material in the automotive, leisure, military and other industries where high temperature resistance and high mechanical strength is required.

  1. Novel bio-based thermoset resins based on epoxidized vegetable oils for structural adhesives

    Science.gov (United States)

    Sivasubramanian, Shivshankar

    Conventional engineered wood composites are bonded for the most part through formaldehyde-based structural adhesives such as urea formaldehyde (UF), melamine formaldehyde (MF), phenol formaldehyde (PF) and resorcinol formaldehyde (RF). Formaldehyde is a known human carcinogen; the occupational exposure and emission after manufacturing of these binders is raising more and more concern. With increasing emphasis on environmental issues, there is clear incentive to replace these hazardous conventional formaldehyde-based binders with cco-friendly resins having similar properties but derived from renewable sources, bearing in mind the economics of the structural wood composite industry. In this thesis, the curing reaction of bio-derived epoxy thermosets with inexpensive, low-toxicity precursors, including polyimines and amino acids was investigated. Epoxidized linseed oil (ELO) and epoxidized soybean oil (ESO) were successfully crosslinked with both branched polyethyleneimine (PEI) and triethylenetetramine (fETA). Epoxidized castor oil (ECO) was crosslinked with polyethyleneimine (PEI), having different molecular weights. Curing conditions were optimized through solvent uptake and soluble fraction analysis. Finally, the mechanical properties of the optimized compositions of rigid bioepoxies were evaluated using dynamic mechanical rheological testing (DMRT). While not as stiff as conventional materials, optimized materials have sufficient room temperature moduli to show promise for coatings and as binders in engineered wood products.

  2. Direct fabrication of ordered mesoporous carbons with super-micropore/small mesopore using mixed triblock copolymers.

    Science.gov (United States)

    Li, Peng; Song, Yan; Tang, Zhihong; Yang, Guangzhi; Yang, Junhe

    2014-01-01

    Ordered mesoporous carbons (OMCs) have been prepared by the strategy of evaporation-induced organic-organic self-assembly method by employing a mixture of amphiphilic triblock copolymers poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (PEO-PPO-PEO) and reverse PPO-PEO-PPO as templates, with soluble in ethanol, low-molecular-weight phenolic resin as precursor, followed by carbonization. It has been found that the as prepared OMCs with porosity that combines super-micropore and small mesopore size distributed from 0.8 to 4 nm, which bridges the pore size from 2 to 3 nm and also for the diversification of the soft-templating synthesis of OMCs. Furthermore, the results showed that the OMCs obtained have mesophase transition from cylindrical p6 mm to centered rectangular c2 mm structure by simply tuning the ratio of PPO-PEO-PPO/PEO-PPO-PEO. PMID:24183444

  3. Morphology control in mesoporous carbon films using solvent vapor annealing.

    Science.gov (United States)

    Qiang, Zhe; Xue, Jiachen; Cavicchi, Kevin A; Vogt, Bryan D

    2013-03-12

    Ordered mesoporous (2-50 nm) carbon films were fabricated using cooperative self-assembly of a phenolic resin oligomer with a novel block copolymer template (poly(styrene-block-N,N-dimethyl-n-octadecylamine p-styrenesulfonate), (PS-b-PSS-DMODA)) synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. Due to the high Tg of the PS segment and the strong interactions between the phenolic resin and the PSS-DMODA, the segmental rearrangement is kinetically hindered relative to the cross-linking rate of the phenolic resin, which inhibits long-range ordering and yields a poorly ordered mesoporous carbon with a broad pore size distribution. However, relatively short exposure (2 h) to controlled vapor pressures of methyl ethyl ketone (MEK) yields significant improvements in the long-range ordering and narrows the pore size distribution. The average pore size increases as the solvent vapor pressure during annealing increases, but an upper limit of p/p0 = 0.85 exists above which the films dewet rapidly during solvent vapor annealing. This approach can be extended using mesityl oxide, which has similar solvent qualities to MEK, but is not easily removed by ambient air drying after solvent annealing. This residual solvent can impact the morphology that develops during cross-linking of the films. These results illustrate the ability to fine-tune the mesostructure of ordered mesoporous carbon films through simple changes in the processing without any compositional changes in the initial cast film. PMID:23394515

  4. Fabrication and Characterization of Inorganic Silver and Palladium Nanostructures within Hexagonal Cylindrical Channels of Mesoporous Carbon

    Directory of Open Access Journals (Sweden)

    Jheng-Guang Li

    2014-06-01

    Full Text Available In this study, we prepared a mesoporous carbon with hexagonally packed mesopores through evaporation-induced self-assembly (EISA—with the diblock copolymer poly(ethylene oxide-b-?-caprolactone (PEO-b-PCL as the template (EO114CL84, phenolic resin as the carbon precursor, hexamethylenetetramine (HMTA as the curing agent, and star octakis-PEO-functionalized polyhedral oligomeric silsesquioxane (PEO–POSS as the structure modifier—and subsequent carbonization. We then took the cylindrical mesoporous carbon as a loading matrix, with AgNO3 and Pd(NO32 as metal precursors, to fabricate Ag nanowire/mesoporous carbon and Pd nanoparticle/mesoporous carbon nanocomposites, respectively, through an incipient wetness impregnation method and subsequent reduction under H2. We used transmission electron microscopy, electron diffraction, small-angle X-ray scattering, N2 isotherm sorption experiment, Raman spectroscopy, and power X-ray diffraction to investigate the textural properties of these nanometal/carbon nanocomposites. Most notably, the Raman spectra of the cylindrical mesoporous carbon, Ag/mesoporous carbon, and Pd/mesoporous carbon revealed interesting phenomena in terms of the ratios of the intensities of the D and G bands (ID/IG, the absolute scattering intensities, and the positions of the D bands.

  5. Templating mesoporous zeolites

    DEFF Research Database (Denmark)

    Egeblad, Kresten; Christensen, Christina Hviid

    2008-01-01

    The application of templating methods to produce zeolite materials with hierarchical bi- or trimodal pore size distributions is reviewed with emphasis on mesoporous materials. Hierarchical zeolite materials are categorized into three distinctly different types of materials: hierarchical zeolite crystals, nanosized zeolite crystals, and supported zeolite crystals. For the pure zeolite materials in the first two categories, the additional meso- or macroporosity can be classified as being either intracrystalline or intercrystalline, whereas for supported zeolite materials, the additional porosity originates almost exclusively from the support material. The methods for introducing mesopores into zeolite materials are discussed and categorized. In general, mesopores can be templated in zeolite materials by use of solid templating, supramolecular templating, or indirect templating. In this categorization of templating methods, the nature of the interface between the zeolite crystal and the mesopore exactly when themesopore starts to form is emphasized. In solid templating, the zeolite crystal is in intimate contact with a solid material that is being removed to produce the mesoporosity. Similarly, in supramolecular templating, the zeolite crystal is in direct contact with a supramolecular assembly of organized surfactants, which is removed to generate the mesopores. On the other hand, in the indirect templating method, the interface is between the zeolite crystal and solvent molecules, or possibly a gas phase. It is shown that the available templating approaches are quite versatile, and accordingly, it is possible to produce a very wide range of hierarchical zeolite materials. The resulting zeolite materials, featuring noncrystallographic mesopores in addition to the crystallographic micropores, exhibit significantly enhanced diffusional properties in comparison with purely microporous zeolite materials. These enhanced mass transport properties have been shown in several cases to result in significantly improved catalytic properties in a range of important reactions.

  6. Resin composites

    DEFF Research Database (Denmark)

    Benetti, Ana Raquel; Peutzfeldt, Anne; Lussi, Adrian; Flury, Simon

    2014-01-01

    OBJECTIVE: To investigate how the modulus of elasticity of resin composites influences marginal quality in restorations submitted to thermocyclic and mechanical loading. METHODS: Charisma, Filtek Supreme XTE and Grandio were selected as they were found to possess different moduli of elasticity but quite similar polymerization contraction. MOD cavities (n=30) were prepared in extracted premolars, restored and then subjected to thermocyclic and mechanical loading. Marginal quality of the restorati...

  7. Review: Resin Composite Filling

    OpenAIRE

    Desmond Ng; Jimmy C. M. Hsiao; Keith C. T. Tong; Harry Kim; Yanjie Mai; Keith H. S. Chan

    2010-01-01

    The leading cause of oral pain and tooth loss is from caries and their treatment include restoration using amalgam, resin, porcelain and gold, endodontic therapy and extraction. Resin composite restorations have grown popular over the last half a century because it can take shades more similar to enamel. Here, we discuss the history and use of resin, comparison between amalgam and resin, clinical procedures involved and finishing and polishing techniques for resin restoration. Although resin ...

  8. Template Directed Synthesis and Characterization of Organic Mesoporous Polymers and their Adsorption Performance for Lysozyme

    Science.gov (United States)

    Sridhar, Manasa

    Three homologous series of MCFs with diverse pore topologies have been synthesized by symbiotic interplay of TMB/P123 (R1) and TEOS/P123 (R2) weight ratios in the initial microemulsion. It was found that the MCFs synthesized at R2 greater than the conventional value suffered significant lag in the mesopore volumes and areas at low concentrations of TMB. However, when R1 is increased beyond 1.0, the difference in the pore volumes and areas became negligible. Many key findings were reported through this study. TEM images revealed that the MCFs synthesized at higher values of R2 prematurely attained larger average pore sizes accompanied with portions displaying constricted worm-like mesostructures. Such bimodal mesophases are accounted by the swelling action of excess amounts of ethanol discharged due to the hydrolysis of increased amounts of TEOS present in the microemulsion along with partial TEOS dissolution in the hydrophobic PPO cores of the TMB/P123 micelles. MCFs synthesized at highest R2 value of 4.4 exhibits unique interconnected rod-like morphologies which are usually not observed for conventional MCFs. MCF produced using R1 = 2.5 and R2 = 3.0 exhibit bimodal mesophases consisting of polyhedral nanofoam-like textures along with regular spherical pores. USAXS results indicate wall thickness as large as 11 nm for MCFs produced at R2 =4.4. These MCFs of interesting mesostructures were employed as nanoscopic templates to produce Mesocellular Phenol Formaldehyde Foams (MPFFs) using vacuum-assisted incipient wetness impregnation technique. The nanocasted MPFFs show large pore volumes up to 1.4 cm3/g, BET surface areas more than 900 m2/g and large pore diameters in the range 27--99 nm depending on the MCF scaffold used. All the MPFFs showed faithful replication of the cavity sizes of their corresponding MCF parent templates. Stunningly, trimodal MPFFs resulted from the nanocasting of MCFs with R1 > 2.2. The resulting pore sizes were attributed to the original bimodal mesophases and the tertiary pore size resulting from the dissolution of silica pore walls. The organic, biocompatible MPFFs were employed as sorbents for Lysozyme immobilization at ambient temperature and under isoelectric condition. MPFFs exhibiting loading capacities of more than 230 mg/g serve to be highly encouraging in pursuing our interests further to achieve even higher uptake through post-synthesis functionalization.

  9. Templating mesoporous zeolites

    DEFF Research Database (Denmark)

    Egeblad, Kresten; Christensen, Christina Hviid; Kustova, Marina; Christensen, Claus H.

    2008-01-01

    The application of templating methods to produce zeolite materials with hierarchical bi- or trimodal pore size distributions is reviewed with emphasis on mesoporous materials. Hierarchical zeolite materials are categorized into three distinctly different types of materials: hierarchical zeolite crystals, nanosized zeolite crystals, and supported zeolite crystals. For the pure zeolite materials in the first two categories, the additional meso- or macroporosity can be classified as being either in...

  10. Immobilization of spent resin with epoxy resin

    International Nuclear Information System (INIS)

    immobilization of spent resin using epoxy resin has been conducted. The spent resin was mixtured with epoxy resin in variation of concentration, i.e., 30, 40, 50, 60, 70 weight percent of spent resin. The mixture were pour into the plastic tube, with a diameter of 40 mm and height of 40 mm. The density, compressive strength and leaching rate were respectively measured by quanta chrome, paul weber apparatus and gamma spectrometer. The results showed that the increasing of waste concentration would be decreased the compressive strength, and increased density by immobilized waste. The leaching rate of 137Cs from waste product was not detected in experiment (author)

  11. Mesoporous molecular sieve catalysts

    DEFF Research Database (Denmark)

    HØjholt, Karen Thrane

    2011-01-01

    This thesis deals with a very specific class of molecular sieves known as zeolites. Zeolites are a class of crystalline aluminosilicates characterised by pores or cavities of molecular dimensions as part of their crystal structure. In this work zeolites were modified for the use and understanding of different catalytic applications. Primarily the zeolites were modified regarding the porosity and the introduction of metals to the framework. The obtained materials were used as solid acid catalysts, as an inert matrix for stabilising metal nanoparticles and as an anchoring material for molecular metal oxide species. Nanosized and mesoporous zeolites were prepared to investigate the effect of inter- or intracrystalline mesopores on the catalytic lifetime in the conversion of methanol to hydrocarbons (MTH). It was found that the mesoporous zeolite with intracrystalline mesopores displayed the significantly longest catalytic lifetime compared to the nanosized zeolites and the conventional counterpart. Even though the introduction of mesopores improved the catalytic lifetime in the MTH reaction it was concluded that the normal benefits from desilication, e.g. mesoporosity and repairing of defects, became masked by the generation of extra-framework aluminum and that the catalytic lifetime was severely dependent on the amount of extra-framework aluminum. Conventional and mesoporous ZSM-5 zeolites were prepared together with the Ga-MFI zeotype analogues to investigate the differences in activity, selectivity and mode of deactivation. The differences in selectivity were primarily ascribed to the difference in the lower acidity of the individual active sites of the Ga-MFI zeotypes compared to the zeolites. In general, the Ga-MFI zeotypes deactivated faster than the ZSM-5 zeolites. Further investigations of the mode of deactivation revealed that the zeolites deactivated due to coke formation and that the Ga-MFI zeotypes deactivated due to loss of the catalytically active Brønsted acid sites caused by hydrolysis of Ga-O bonds leading to formation of inactive extra-framework gallium. Zeolites can not only be used as solid acid catalysts but can also be used as a size-selective matrix. It was shown that it is possible to encapsulate 1-2 nm sized gold nanoparticles by silicalite-1 or ZSM-5 zeolite crystals thereby forming a sintering-stable and substrate size-selective oxidation catalyst. After carrying out calcination experiments, both in situ and ex situ indicated that the gold nanoparticles embedded in the crystals were highly stable towards sintering. The catalytic tests proved that the embedded gold nanoparticles were active in selective aldehyde oxidation and were only accessible through the micropores. Furthermore, preliminary work was done using mesoporous ZSM-5 zeolites as support material for anchoring molecular CoMo6 species for the application as potential bi-functional catalyst in simultaneous hydrodesulfurisation (HDS) and hydrocracking. HDS activity tests revealed that the anchoring improved the activity compared to an impregnated counterpart.

  12. Mesoporous materials for antihydrogen production.

    Science.gov (United States)

    Consolati, Giovanni; Ferragut, Rafael; Galarneau, Anne; Di Renzo, Francesco; Quasso, Fiorenza

    2013-05-01

    Antimatter is barely known by the chemist community and this article has the vocation to explain how antimatter, in particular antihydrogen, can be obtained, as well as to show how mesoporous materials could be used as a further improvement for the production of antimatter at very low temperatures (below 1 K). The first experiments with mesoporous materials highlighted in this review show very promising and exciting results. Mesoporous materials such as mesoporous silicon, mesoporous material films, pellets of MCM-41 and silica aerogel show remarkable features for antihydrogen formation. Yet, the characteristics for the best future mesoporous materials (e.g. pore sizes, pore connectivity, shape, surface chemistry) remain to be clearly identified. For now among the best candidates are pellets of MCM-41 and aerogel with pore sizes between 10 and 30 nm, possessing hydrophobic patches on their surface to avoid ice formation at low temperature. From a fundamental standpoint, antimatter experiments could help to shed light on open issues, such as the apparent asymmetry between matter and antimatter in our universe and the gravitational behaviour of antimatter. To this purpose, basic studies on antimatter are necessary and a convenient production of antimatter is required. It is exactly where mesoporous materials could be very useful. PMID:23250616

  13. Studies on Lignin-Based Adhesives for Particleboard Panels

    OpenAIRE

    ÇET?N, Nihat Sami; ÖZMEN, Nilgül

    2003-01-01

    The ultimate aim of this work was to develop a phenolic resin for partially replacing phenol with modified organosolv lignin in phenol-formaldehyde (PF) resin production. The lignin-formaldehyde relationship was determined in a reactivity test. Organosolv lignin-phenol-formaldehyde (LPF) resins were produced in a two-step preparation with different additions of lignin. The method selected for the manufacture of lignin resins dealt with modification of the lignin by the methylolation route. Th...

  14. Peptide modified mesoporous silica nanocontainers†

    OpenAIRE

    Porta, Fabiola; Lamers, Gerda E. M.; Zink, Jeffrey I.; Kros, Alexander

    2011-01-01

    Here we report a new peptide modified mesoporous silica nanocontainer (PMSN) as a novel controlled release system. The peptides are part of a stimuli responsive nanovalve and ensure an efficient cellular uptake.

  15. Hydrophilic and mesoporous SiO2-TiO2-SO3H system for fuel cell membrane applications

    International Nuclear Information System (INIS)

    Graphical abstract: The composite films containing SiO2-TiO2-SO3H resin additives, with strong water retention capabilities, showed superior proton conductivity, even at 120 oC and 25% RH, as well as a slightly improved current density at 30% RH and 70 oC, when compared to costly Nafion film. Display Omitted Research highlights: ? The hydrophilic and mesoporous SiO2-TiO2-SO3H resins have a potential to be used as alternative membrane source materials in PEFCs. ? The sulfonation for hydrophilicity is conducted via simple chelating chemistry between catecholic groups and surface Ti ions. ? The proton conductivity of SiO2-TiO2-SO3H composite films is superior to the commercial Nafion film. - Abstract: Hydrophilic and mesoporous sulfonated SiO2-TiO2-SO3H systems as new additives for fuel cell electrolyte membranes are directly synthesized by the binary sol-gel reaction of TEOS-TiCl4 and consecutive sulfonation with a hydrophilic generator, dihydroxy-m-benzenedisulfonic acid disodium salt. The sulfonation approach makes use of the simple chelating chemistry between the catecholic groups (dihydroxy benzene) and surface Ti ions of the inorganic ordered mesoporous SBA-15 structure. The system is successfully employed in fuel cell membrane applications with a composite Nafion membrane mixed with a mesoporous hydrophilic resin additive, and reveals an obvious enhancement of the proton conductivity at low humidity and elevated temperatures. This improvement was attributed to the excellent water retention capability of the hydrophilic mesoporous resin.

  16. Engineered monodisperse mesoporous materials

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, R.S.; Small, J.H.; Lagasse, R.R.; Schroeder, J.L.; Jamison, G.M.

    1997-08-01

    Porous materials technology has developed products with a wide variety of pore sizes ranging from 1 angstrom to 100`s of microns and beyond. Beyond 15{angstrom} it becomes difficult to obtain well ordered, monodisperse pores. In this report the authors describe efforts in making novel porous material having monodisperse, controllable pore sizes spanning the mesoporous range (20--500 {angstrom}). They set forth to achieve this by using unique properties associated with block copolymers--two linear homopolymers attached at their ends. Block copolymers phase separate into monodisperse mesophases. They desired to selectively remove one of the phases and leave the other behind, giving the uniform monodisperse pores. To try to achieve this the authors used ring-opening metathesis polymerization to make the block copolymers. They synthesized a wide variety of monomers and surveyed their polymers by TGA, with the idea that one phase could be made thermally labile while the other phase would be thermally stable. In the precipitated and sol-gel processed materials, they determined by porosimetry measurements that micropores, mesopores, and macropores were created. In the film processed sample there was not much porosity present. They moved to a new system that required much lower thermal treatments to thermally remove over 90% of the labile phase. Film casting followed by thermal treatment and solvent extraction produced the desired monodisperse materials (based solely on SEM results). Modeling using Density Functional Theory was also incorporated into this project. The modeling was able to predict accurately the domain size and spacing vs. molecular weight for a model system, as well as accurate interfacial thicknesses.

  17. Asphaltene-resin association

    Energy Technology Data Exchange (ETDEWEB)

    Sirota, E.; Peczak, P. [ExxonMobil Research and Engineering Co., Houston, TX (United States). Corporate Strategic Research

    2008-07-01

    This study examined the association of resins with asphaltenes within the context of asphaltenes-as-colloidal-aggregates being peptized by surfactant-like resin species. Both solubility and phase behaviour data was presented along with scattering results to clarify questions regarding meaning of association. Questions regarding the size of resin-peptized asphaltene aggregates, clustering, phase separation and co-precipitation were discussed. The study showed that pentane resins must form a continuum, as one can continuously slide the definition of resins and asphaltenes just by choice of solvent and solvent mixtures. This paper explained this behaviour by considering the local composition in a solution of complex molecules.

  18. Mesoporous Silicate Materials in Sensing

    Directory of Open Access Journals (Sweden)

    Paul T. Charles

    2008-08-01

    Full Text Available Mesoporous silicas, especially those exhibiting ordered pore systems and uniform pore diameters, have shown great potential for sensing applications in recent years. Morphological control grants them versatility in the method of deployment whether as bulk powders, monoliths, thin films, or embedded in coatings. High surface areas and pore sizes greater than 2 nm make them effective as adsorbent coatings for humidity sensors. The pore networks also provide the potential for immobilization of enzymes within the materials. Functionalization of materials by silane grafting or through cocondensation of silicate precursors can be used to provide mesoporous materials with a variety of fluorescent probes as well as surface properties that aid in selective detection of specific analytes. This review will illustrate how mesoporous silicas have been applied to sensing changes in relative humidity, changes in pH, metal cations, toxic industrial compounds, volatile organic compounds, small molecules and ions, nitroenergetic compounds, and biologically relevant molecules.

  19. Aligned mesoporous architectures and devices.

    Energy Technology Data Exchange (ETDEWEB)

    Brinker, C. Jeffrey; Lu, Yunfeng (University of California Los Angeles, Los Angeles, CA)

    2011-03-01

    This is the final report for the Presidential Early Career Award for Science and Engineering - PECASE (LDRD projects 93369 and 118841) awarded to Professor Yunfeng Lu (Tulane University and University of California-Los Angeles). During the last decade, mesoporous materials with tunable periodic pores have been synthesized using surfactant liquid crystalline as templates, opening a new avenue for a wide spectrum of applications. However, the applications are somewhat limited by the unfavorabe pore orientation of these materials. Although substantial effort has been devoted to align the pore channels, fabrication of mesoporous materials with perpendicular pore channels remains challenging. This project focused on fabrication of mesoporous materials with perpendicularly aligned pore channels. We demonstrated structures for use in water purification, separation, sensors, templated synthesis, microelectronics, optics, controlled release, and highly selective catalysts.

  20. Determination of mercury by flow injection solid phase extraction coupled with on-line hydride generation ETAAS using as solid phase extractant a new functionalized mesoporous silica

    OpenAIRE

    López Guerrero, María del Mar; Siles Cordero, María Teresa; Vereda Alonso, Elisa Isabel; García de Torres, Amparo; Cano Pavón, José Manuel

    2013-01-01

    A chelating resin, [1,5 bis(di-2-pyridyl) methylene thiocarbohydrazide] bonded to mesoporous silica (DPTH-ms), has been used as a novel solid phase extractant. This resin has some advantages compared to most of other chelating adsorbents. Therefore, the aim is to develop a reliable method for determination of the aforementioned element from natural water samples by the on-line column preconcentration/HG-ETAAS using the resin DPTH-ms. With all experimental variables optimized, a linear cal...

  1. Single crystalline mesoporous silicon nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Hochbaum, Allon; Dargas, Daniel; Hwang, Yun Jeong; Yang, Peidong

    2009-08-18

    Herein we demonstrate a novel electroless etching synthesis of monolithic, single-crystalline, mesoporous silicon nanowire arrays with a high surface area and luminescent properties consistent with conventional porous silicon materials. The photoluminescence of these nanowires suggest they are composed of crystalline silicon with small enough dimensions such that these arrays may be useful as photocatalytic substrates or active components of nanoscale optoelectronic devices. A better understanding of this electroless route to mesoporous silicon could lead to facile and general syntheses of different narrow bandgap semiconductor nanostructures for various applications.

  2. Amine-functionalized mesoporous polymer as potential sorbent for nickel preconcentration from electroplating wastewater.

    Science.gov (United States)

    Islam, Aminul; Zaidi, Noushi; Ahmad, Hilal; Kumar, Suneel

    2015-05-01

    In this study, mesoporous glycidyl methacrylate-divinylbenzene-based chelating resin was synthesized and grafted with diethylenetriamine through epoxy ring-opening reaction. The synthesized resin was characterized by elemental analysis, infrared spectroscopy, surface area and pore size analysis, scanning electron microscopy, energy-dispersive spectroscopy, and thermogravimetry. The resin was used for the first time as an effective sorbent for the preconcentration of nickel in electroplating wastewater samples. The analytical variables like pH, flow rate for sorption/desorption, and eluate selection were systematically investigated and optimized. The uniform and monolayer sorption behavior of resin for nickel was proved by an evident fit of the equilibrium data to a Langmuir isotherm model. Under optimized conditions, the resin was observed to show a good sorption capacity of 20.25 mg g(-1) and >96% recovery of nickel even in the presence of a large number of competitive matrix ions. Its ability to extract trace amount of nickel was exhibited by low preconcentration limit (5.9 ?g L(-1)). The calibration curve was found to be linear (R(2)?=?0.998) in the concentration range of 6.0-400.0 ?g L(-1). Coefficient of variation of less than 5 for all the analysis indicated good reproducibility. The reliability was evaluated by the analysis of standard reference material (SRM) and recovery experiments. The applicability of the resin for the systematic preconcentration of nickel is substantiated by the analysis of electroplating wastewater and river water samples. Graphical abstract ?. PMID:25561258

  3. Biocompatibility of composite resins

    OpenAIRE

    Mousavinasab, Sayed Mostafa

    2011-01-01

    Dental materials that are used in dentistry should be harmless to oral tissues, so they should not contain any leachable toxic and diffusible substances that can cause some side effects. Reports about probable biologic hazards, in relation to dental resins, have increased interest to this topic in dentists. The present paper reviews the articles published about biocompatibility of resin-restorative materials specially resin composites and monomers which are mainly based on Bis-GMA and concern...

  4. Magnetic mesoporous material for the sequestration of algae

    Energy Technology Data Exchange (ETDEWEB)

    Trewyn, Brian G.; Kandel, Kapil; Slowing, Igor Ivan; Lee, Show-Ling

    2014-09-09

    The present invention provides a magnetic mesoporous nanoparticle that includes a mesoporous silicate nanoparticle and iron oxide. The present invention also provides a method of using magnetic mesoporous nanoparticles to sequester microorganisms from a media.

  5. Facile synthesis of hypercrosslinked resins via chloromethylation and continuous condensation of simple aryl molecules

    Indian Academy of Sciences (India)

    Xiaoyan Zhang; Qiu Jin; Libo Dai; Siguo Yuan

    2011-07-01

    A sort of non-polystyrene type hypercrosslinked resin was firstly synthesized through chloromethylation of simple aryl molecules (benzene, toluene, naphthalene, diphenyl), succedent continuous Friedel–Crafts alkylation polymerization and post-crosslinking reaction. The chemical and porous structures of these novel resins were characterized with BET, FT–IR and elementary analysis, respectively. The results showed that these novel adsorptive materials possessing abundant crosslinked networks had high specific surface areas (up to 1191.26 m2/g), large pore volumes (0.2–1.4 ml/g), narrow pore size distributions (mainly in the range of micropores and small mesopores).

  6. 21 CFR 177.2600 - Rubber articles intended for repeated use.

    Science.gov (United States)

    2010-04-01

    21 Food and Drugs 3 2010-04-01...in contact with foods of Types I, II...sulfonated. Phenol-formaldehyde resin. Pine tar...persulfate. Sodium formaldehyde sulfoxylate. Sodium...for use with dry food are so...

  7. 46 CFR Table II to Part 150 - Grouping of Cargoes

    Science.gov (United States)

    2010-10-01

    ...Xylene mixtures Butylbenzene Butyl phenol, Formaldehyde resin in Xylene Butyl toluene Cumene Cymene Decylbenzene...formate iso-Butyl isobutyrate n-Butyl propionate Calcium alkyl(C9)phenol sulfide, polyolefin...

  8. Ordered mesoporous silica materials with complicated structures

    KAUST Repository

    Han, Yu

    2012-05-01

    Periodically ordered mesoporous silicas constitute one of the most important branches of porous materials that are extensively employed in various chemical engineering applications including adsorption, separation and catalysis. This short review gives an introduction to recently developed mesoporous silicas with emphasis on their complicated structures and synthesis mechanisms. In addition, two powerful techniques for solving complex mesoporous structures, electron crystallography and electron tomography, are compared to elucidate their respective strength and limitations. Some critical issues and challenges regarding the development of novel mesoporous structures as well as their applications are also discussed. © 2011 Elsevier Ltd.

  9. Cellular membrane trafficking of mesoporous silica nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Fang, I-Ju

    2012-06-21

    This dissertation mainly focuses on the investigation of the cellular membrane trafficking of mesoporous silica nanoparticles. We are interested in the study of endocytosis and exocytosis behaviors of mesoporous silica nanoparticles with desired surface functionality. The relationship between mesoporous silica nanoparticles and membrane trafficking of cells, either cancerous cells or normal cells was examined. Since mesoporous silica nanoparticles were applied in many drug delivery cases, the endocytotic efficiency of mesoporous silica nanoparticles needs to be investigated in more details in order to design the cellular drug delivery system in the controlled way. It is well known that cells can engulf some molecules outside of the cells through a receptor-ligand associated endocytosis. We are interested to determine if those biomolecules binding to cell surface receptors can be utilized on mesoporous silica nanoparticle materials to improve the uptake efficiency or govern the mechanism of endocytosis of mesoporous silica nanoparticles. Arginine-glycine-aspartate (RGD) is a small peptide recognized by cell integrin receptors and it was reported that avidin internalization was highly promoted by tumor lectin. Both RGD and avidin were linked to the surface of mesoporous silica nanoparticle materials to investigate the effect of receptor-associated biomolecule on cellular endocytosis efficiency. The effect of ligand types, ligand conformation and ligand density were discussed in Chapter 2 and 3. Furthermore, the exocytosis of mesoporous silica nanoparticles is very attractive for biological applications. The cellular protein sequestration study of mesoporous silica nanoparticles was examined for further information of the intracellular pathway of endocytosed mesoporous silica nanoparticle materials. The surface functionality of mesoporous silica nanoparticle materials demonstrated selectivity among the materials and cancer and normal cell lines. We aimed to determine the specific organelle that mesoporous silica nanoparticles could approach via the identification of harvested proteins from exocytosis process. Based on the study of endo- and exocytosis behavior of mesoporous silica nanoparticle materials, we can design smarter drug delivery vehicles for cancer therapy that can be effectively controlled. The destination, uptake efficiency and the cellular distribution of mesoporous silica nanoparticle materials can be programmable. As a result, release mechanism and release rate of drug delivery systems can be a well-controlled process. The deep investigation of an endo- and exocytosis study of mesoporous silica nanoparticle materials promotes the development of drug delivery applications.

  10. Hydrophilic and mesoporous SiO{sub 2}-TiO{sub 2}-SO{sub 3}H system for fuel cell membrane applications

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Lan-Young [Department of Fine Chemical Engineering and Chemistry, Chungnam National University, 220 Kung-dong, Yuseong-gu, Daejeon 305-764 (Korea, Republic of); Oh, Song-Yul [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan); Matsuda, Atsunori, E-mail: matsuda@ee.tut.ac.j [Department of Materials Science, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan); Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580 (Japan); Lee, Chang-Soo [Department of Chemical Engineering, Chungnam National University, 220 Kung-dong, Yuseong-gu, Daejeon 305-764 (Korea, Republic of); Kim, Dong-Pyo, E-mail: dpkim@cnu.ac.k [Department of Fine Chemical Engineering and Chemistry, Chungnam National University, 220 Kung-dong, Yuseong-gu, Daejeon 305-764 (Korea, Republic of); Graduate School of Analytical Science and Technology, Chungnam National University, 220 Kung-dong, Yuseong-gu, Daejeon 305-764 (Korea, Republic of)

    2011-03-30

    Graphical abstract: The composite films containing SiO{sub 2}-TiO{sub 2}-SO{sub 3}H resin additives, with strong water retention capabilities, showed superior proton conductivity, even at 120 {sup o}C and 25% RH, as well as a slightly improved current density at 30% RH and 70 {sup o}C, when compared to costly Nafion film. Display Omitted Research highlights: The hydrophilic and mesoporous SiO{sub 2}-TiO{sub 2}-SO{sub 3}H resins have a potential to be used as alternative membrane source materials in PEFCs. The sulfonation for hydrophilicity is conducted via simple chelating chemistry between catecholic groups and surface Ti ions. The proton conductivity of SiO{sub 2}-TiO{sub 2}-SO{sub 3}H composite films is superior to the commercial Nafion film. - Abstract: Hydrophilic and mesoporous sulfonated SiO{sub 2}-TiO{sub 2}-SO{sub 3}H systems as new additives for fuel cell electrolyte membranes are directly synthesized by the binary sol-gel reaction of TEOS-TiCl{sub 4} and consecutive sulfonation with a hydrophilic generator, dihydroxy-m-benzenedisulfonic acid disodium salt. The sulfonation approach makes use of the simple chelating chemistry between the catecholic groups (dihydroxy benzene) and surface Ti ions of the inorganic ordered mesoporous SBA-15 structure. The system is successfully employed in fuel cell membrane applications with a composite Nafion membrane mixed with a mesoporous hydrophilic resin additive, and reveals an obvious enhancement of the proton conductivity at low humidity and elevated temperatures. This improvement was attributed to the excellent water retention capability of the hydrophilic mesoporous resin.

  11. Reduction of polyester resin shrinkage by means of epoxy resin

    International Nuclear Information System (INIS)

    An attempt was made to decrease the shrinkage of unsaturated polyester resin, taking place during radiation-induced curing, by the addition of epoxy resin. In order to combine chemically both resins, the epoxy component was modified with cinnamic and acrylic acids. A composition of 90 parts of polyester resin, 10 parts of epoxy resin modified with cinnamic acid, and 150 parts of a silica filler showed a volume shrinkage of 1.2%. (author)

  12. Cleanup of demineralizer resins

    International Nuclear Information System (INIS)

    Radiocesium is being removed from demineralizers A and B (DA and DB) by a process that was developed from laboratory tests on small samples of resin from the demineralizers. The process was designed to elute the radiocesium from the demineralizer resins and then to resorb it onto the zeolite ion exchangers contained in the Submerged Demineralizer System (SDS). It was also required to limit the maximum cesium activities in the resin eluates (SDSD feeds) so that the radiation field surrounding the pipelines would not be excessive. The process consisted of 17 stages of batch elution. In the initial stage, the resin was contacted with 0.18 M boric acid. Subsequent stages subjected the resin to increasing concentrations of sodium in NaH2BO3-H3BO3 solution (total boron= 0.35 M) and then 1 M sodium hydroxide in the final stages. Results on the performance of the process in the cleanup of the demineralizers at TMI-2 are compared with those obtained from laboratory tests with small samples of the DA and DB resins. To date, 15 stages of batch elution have been completed on the demineralizers at TMI-2, which resulted in the removal of about 750 Ci of radiocesium from DA and about 3300 Ci from DB

  13. General strategy for fabricating thoroughly mesoporous nanofibers

    KAUST Repository

    Hou, Huilin

    2014-12-03

    Recently, preparation of mesoporous fibers has attracted extensive attentions because of their unique and broad applications in photocatalysis, optoelectronics, and biomaterials. However, it remains a great challenge to fabricate thoroughly mesoporous nanofibers with high purity and uniformity. Here, we report a general, simple and cost-effective strategy, namely, foaming-assisted electrospinning, for producing mesoporous nanofibers with high purity and enhanced specific surface areas. As a proof of concept, the as-fabricated mesoporous TiO2 fibers exhibit much higher photocatalytic activity and stability than both the conventional solid counterparts and the commercially available P25. The abundant vapors released from the introduced foaming agents are responsible for the creation of pores with uniform spatial distribution in the spun precursor fibers. The present work represents a critically important step in advancing the electrospinning technique for generating mesoporous fibers in a facile and universal manner.

  14. Single crystalline mesoporous silicon nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Hochbaum, A.I.; Gargas, Daniel; Jeong Hwang, Yun; Yang, Peidong

    2009-08-04

    Herein we demonstrate a novel electroless etching synthesis of monolithic, single-crystalline, mesoporous silicon nanowire arrays with a high surface area and luminescent properties consistent with conventional porous silicon materials. These porous nanowires also retain the crystallographic orientation of the wafer from which they are etched. Electron microscopy and diffraction confirm their single-crystallinity and reveal the silicon surrounding the pores is as thin as several nanometers. Confocal fluorescence microscopy showed that the photoluminescence (PL) of these arrays emanate from the nanowires themselves, and their PL spectrum suggests that these arrays may be useful as photocatalytic substrates or active components of nanoscale optoelectronic devices.

  15. Ordered mesoporous carbon-titania composites and their enhanced photocatalytic properties.

    Science.gov (United States)

    Wickramaratne, Nilantha P; Jaroniec, Mietek

    2015-07-01

    A series of ordered mesoporous titania-carbon composites was synthesized by self-assembly of carbon and titania precursors in the presence of Pluronic F127 block copolymer as a template under acidic conditions. Resorcinol and formaldehyde were used as carbon precursors and titanium isopropoxide was employed as titania precursor. Pluronic F127 [poly(ethylene oxide) - poly(propylene oxide) - poly(ethylene oxide) triblock copolymer] was employed as a soft template. The controlled polymerization of phenolic resin precursors and condensation of titania precursor in hydrophilic domains of the block copolymer template followed by carbonization resulted in ordered mesoporous titania-carbon composites. These composites possessed uniform ordered cylindrical mesopores (7-8 nm) created by thermal decomposition of the soft template, crystalline titania particles (anatase phase, 7-8 nm) embedded in the carbon matrix, and high percentage of titania (up to 48%). N2 adsorption analysis showed that the aforementioned composites exhibited large surface area (close to reaching 600 m(2)/g) and enhanced photocatalytic activity toward photodegradation of rhodomine B due to the presence of titania nanoparticles uniformly dispersed in the carbon mesostructure. PMID:25648111

  16. Surfactant-Templated Mesoporous Metal Oxide Nanowires

    Directory of Open Access Journals (Sweden)

    Stacy Baber

    2010-01-01

    Full Text Available We demonstrate two approaches to prepare mesoporous metal oxide nanowires by surfactant assembly and nanoconfinement via sol-gel or electrochemical deposition. For example, mesoporous Ta2O5 and zeolite nanowires are prepared by block copolymer Pluronic 123-templated sol-gel method, and mesoporous ZnO nanowires are prepared by electrodeposition in presence of anionic surfactant sodium dodecyl sulfate (SDS surfactant, in porous membranes. The morphologies of porous nanowires are studied by scanning electron microscopy (SEM and transmission electron microscopy (TEM analyses.

  17. Petroleum resins for bitumens modification

    OpenAIRE

    Grynyshyn, Oleg; Bratychak, Michael; Krynytskiy, Volodymyr; Donchak, Volodymyr

    2008-01-01

    The process of tar and industrial petroleum resin "Piroplast-2" joint oxidation has been investigated. The experimental results of the main regularities researches of the obtaining process of petroleum resins with carboxyl groups based on the pyrocondensate C9 fraction of hydrocarbon feedstock pyrolysis have been shown. It has been established that synthesized petroleum resins may be used for the modification of petroleum bitumens. ??????? ?????? ????????? ????????? ??????...

  18. Preparation of irregular mesoporous hydroxyapatite

    International Nuclear Information System (INIS)

    An irregular mesoporous hydroxyapatite (meso-HA), Ca10(PO4)6(OH)2, is successfully prepared from Ca(NO3)2.4H2O and NH4H2PO4 using surfactant cetyltrimethyl ammonium bromide (CTAB) as template. Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) results reveal that the positive head of CTAB is assembled on the surface precipitated HA and much NH4+ is enclosed in precipitated HA before calcination. Field scanning electron microscope (FSEM) reveals that there exist many interconnected pores throughout the HA reticular skeleton. Nitrogen adsorption-desorption experiment exhibits a mesoporous material type IV curve, and pore size distribution calculated from the desorption branch of the isotherms based on Barrett-Joyner-Halenda (BJH) model shows that most pores throughout the HA reticular skeleton are sized at about 40 nm, but the pores are not uniform on the whole, owning to decomposition of the 'organic' CTAB templating structures and ammonium salt enclosed in the precipitated HA. The specific surface area of irregular meso-HA is calculated to be 37.6 m2/g according to the Brunauer-Emmett-Teller (BET) equation. Moreover, after polylactic acid/meso-HA (PLA/meso-HA) composites degraded 12 weeks in normal saline at 37 deg. C, the interconnected pores throughout the HA skeleton were enlarged and sized in micron degree, which resemble trabecular bone structure very much

  19. Preparation and characterization of multifunctional magnetic mesoporous calcium silicate materials

    OpenAIRE

    Jianhua Zhang, Yufang Zhu, Jie Li, Min Zhu, Cuilian Tao and Nobutaka Hanagata

    2013-01-01

    We have prepared multifunctional magnetic mesoporous Fe–CaSiO3 materials using triblock copolymer (P123) as a structure-directing agent. The effects of Fe substitution on the mesoporous structure, in vitro bioactivity, magnetic heating ability and drug delivery property of mesoporous CaSiO3 materials were investigated. Mesoporous Fe–CaSiO3 materials had similar mesoporous channels (5–6 nm) with different Fe substitution. When 5 and 10% Fe were substituted for Ca in mesoporous CaSiO3 materials...

  20. Aggregation-free gold nanoparticles in ordered mesoporous carbons: toward highly active and stable heterogeneous catalysts.

    Science.gov (United States)

    Wang, Shuai; Zhao, Qingfei; Wei, Huimin; Wang, Jian-Qiang; Cho, Minhyung; Cho, Hae Sung; Terasaki, Osamu; Wan, Ying

    2013-08-14

    A coordination-assisted synthetic approach is reported here for the synthesis of highly active and stable gold nanoparticle catalysts in ordered mesoporous carbon materials using triblock copolymer F127 as a structure-directing agent, thiol-containing silane as a coordination agent, HAuCl4 as a gold source, and phenolic resin as a carbon source. Upon carbonization, the gold precursor becomes reduced to form monodispersed Au nanoparticles of ca. 9.0 nm, which are entrapped or confined by the "rigid" mesoporous carbonaceous framework. Nanoparticle aggregation is inhibited even at a high temperature of 600 °C. After removal of the silica component, the materials possess the ordered mesostructure, high surface area (~1800 m(2)/g), large pore volume (~1.19 cm(3)/g), and uniform bimodal mesopore size (gold nanoparticles are highly exposed because of the interpenetrated bimodal pores in the carbon framework, which exhibit excellent catalytic performance. A completely selective conversion of benzyl alcohol in water to benzoic acid can be achieved at 90 °C and 1 MPa oxygen. Benzyl alcohol can also be quantitatively converted to benzoic acid at 60 °C even under an atmospheric pressure, showing great advantages in green chemistry. The catalysts are stable, poison resistant, and reusable with little activity loss due to metal leaching. The silane coupling agent played several functions in this approach: (1) coordinating with gold species by the thiol group to benefit formation of monodispersed Au nanoparticles; (2) reacting with phenolic resins by silanol groups to form relatively "rigid" composite framework; (3) pore-forming agent to generate secondary pores in carbon pore walls, which lead to higher surface area, larger pore volumes, and higher accessibility to to the gold nanoparticles. Complete removal of the silica component proves to have little effect on the catalytic performance of entrapped Au nanoparticles. PMID:23865622

  1. Thermally conductive polymers

    Science.gov (United States)

    Byrd, N. R.; Jenkins, R. K.; Lister, J. L. (inventors)

    1971-01-01

    A thermally conductive polymer is provided having physical and chemical properties suited to use as a medium for potting electrical components. The polymer is prepared from hydroquinone, phenol, and formaldehyde, by conventional procedures employed for the preparation of phenol-formaldehyde resins. While the proportions of the monomers can be varied, a preferred polymer is formed from the monomers in a 1:1:2.4 molar or ratio of hydroquinone:phenol:formaldehyde.

  2. HIGH-PERFORMANCE CELLULOSE NANOFIBRIL COMPOSITE FILMS

    OpenAIRE

    Yan Qing,; Ronald Sabo,; Yiqiang Wu,; Zhiyong Cai

    2012-01-01

    Cellulose nanofibril/phenol formaldehyde (CNF/PF) composite films with high work of fracture were prepared by filtering a mixture of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidized wood nanofibers and water-soluble phenol formaldehyde with resin contents ranging from 5 to 20 wt%, followed by hot pressing. The composites were characterized by tensile testing, dynamic mechanical analysis, scanning electron microscopy, atomic force microscopy, thermo-gravimetric analysis, and moisture/wate...

  3. Mesoporous Silicon Far Infrared Filters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I proposal describes a novel method to make optical filters based on mesoporous silicon multilayers, for use at cold temperatures in the far...

  4. Resins for condensate polishing

    International Nuclear Information System (INIS)

    Condensate polishing is, in principle, very simple and requires low TDS water, ie condensate, containing at most a few ppm of dissolved salts, gases and insoluble corrosion products, at near ambient temperatures, to be demineralised and filtered (at high linear and specific flow rates) to a quality acceptable as feedwater back to the boiler. In practice the process can be, and usually is, quite complex, and this complexity reflects the quality and quantity of treated water required, the nature of the components in the feedwater, the type and characteristics and condition of the resins employed, the design and operation of the engineering equipment (mixed beds) and the effect on treated water quality which interactions between the other variables can have. A brief review is given of the basic requirements expected from ion exchange resins used for condensate polishing together with mention of the many process features which affect the performance of the resins and influence the thinking of the resin manufacturers. Specifications are given for treated condensate in Magnox, AGR and PWR nuclear power plants. (U.K.)

  5. Nanostructured diluted magnetic semiconductors within mesoporous silica

    OpenAIRE

    Brieler, Felix

    2005-01-01

    In this work the successful formation of several diluted magnetic semiconductors inside various mesoporous host matrices is shown. For that purpose, different high quality mesoporous silicas were synthesised. Because of the possibility to obtain nanostructured quantum wires inside the respective pore systems, hexagonally ordered structures of the MCM-41 and SBA-15 kind were chosen as hosts for the intra-pore formation of the DMS nanoparticles. Later on it became obvious though, that the forma...

  6. Tailored adsorption of enzymes onto mesoporous silicates.

    OpenAIRE

    Gaffney, Darragh

    2011-01-01

    The objective of this research is to synthesise mesoporous silicates, incorporate metal complexes on to the surface of the silicates post synthesis and utilise these materials for the immobilisation of histidine-tagged enzymes to form stable, reusable biocatalysts. Studies in the synthesis of a range of mesoporous silicates and subsequent postsynthetic metal-cyclam functionalisation are presented. The generation of nickel-cyclam functionalised MCM-41/89, SBA-15 and MCF was successful...

  7. Mesoporous zirconium phosphate from yeast biotemplate.

    Science.gov (United States)

    Tian, Xiuying; He, Wen; Cui, Jingjie; Zhang, Xudong; Zhou, Weijia; Yan, Shunpu; Sun, Xianan; Han, Xiuxiu; Han, Shanshan; Yue, Yuanzheng

    2010-03-01

    Mesoporous zirconium phosphate has attracted increasing interest due to its extraordinary functionalities. In particular, great progress has been made in the synthesis of mesoporous zirconium phosphate using traditional approaches. However, synthesis of mesoporous zirconium phosphate using yeast as biotemplate has not been well studied so far. Here, we show that zirconium phosphate with a mesoporous structure has been synthesized under ambient conditions using yeast as biotemplate. The derived samples were examined by X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), thermogravimetry/differential thermal analysis (TG/DTA), fourier transform infrared spectroscopy (FTIR), and N(2) adsorption-desorption isotherms. A biotemplated mesoporous zirconium phosphate, possessing a specific surface area (Brunauer-Emmett-Teller, BET) of 217.64 m(2) g(-1), a narrow pore distribution centered at 2.7 nm, and pore volume of 0.24 cm(3) g(-1), was obtained. We discover that amide carboxyl groups of yeast play an important role in the chemical interaction between protein molecules and zirconium phosphate nanoparticles. Interestingly, an air electrode fabricated using mesoporous zirconium phosphate exhibits remarkable electrocatalytic activity for oxygen reduction reaction (ORR), compared to that of the electrolytic manganese dioxide (EMD) air electrode employed commercially, which has important applications in fuel cell technologies. PMID:20031146

  8. Mesoporous Carbon Produced from Tri-constituent Mesoporous Carbon-silica Composite for Water Purification

    KAUST Repository

    Yu, Yanjie

    2012-05-01

    Highly ordered mesoporous carbon-silica nanocomposites with interpenetrating carbon and silica networks were synthesized by the evaporation-induced tri-constituent co- assembly approach. The removal of silica by concentrated NaOH solution produced mesoporous carbons, which contained not only the primary large pores, but also the secondary mesopores in the carbon walls. The thus synthesized mesoporous carbon was further activated by using ZnCl2. The activated mesoporous carbon showed an improved surface area and pore volume. The synthesized mesoporous carbon was tested for diuron removal from water and the results showed that the carbon gave a fast diuron adsorption kinetics and a high diuron removal capacity, which was attributable to the primary mesopore channels being the highway for mass transfer, which led to short diffusion path length and easy accessibility of the interpenetrated secondary mesopores. The optimal adsorption capacity of the porous carbon was determined to be 390 mg/g, the highest values ever reported for diuron adsorption on carbon-based materials.

  9. Preparation and properties of mesoporous silica/bismaleimide/diallylbisphenol composites with improved thermal stability, mechanical and dielectric properties

    Directory of Open Access Journals (Sweden)

    2011-06-01

    Full Text Available New composites with improved thermal stability, mechanical and dielectric properties were developed, which consist of 2,2'-diallylbisphenol A (DBA/4,4'-bismaleimidodiphenylmethane (BDM resin and a new kind of organic/inorganic mesoporous silica (MPSA. Typical properties (curing behavior and mechanism, thermal stability, mechanical and dielectric properties of the composites were systematically investigated, and their origins were discussed. Results show that MPSA/DBA/BDM composites have similar curing temperature as DBA/BDM resin does; however, they have different curing mechanisms, and thus different crosslinked networks. The content of MPSA has close relation with the integrated performance of cured composites. Compared with cured DBA/BDM resin, composites with suitable content of MPSA show obviously improved flexural strength and modulus as well as impact strength; in addition, all composites not only have lower dielectric constant and similar frequency dependence, more interestingly, they also exhibit better stability of frequency on dielectric loss. For thermal stability, the addition of MPSA to DBA/BDM resin significantly decreases the coefficient of thermal expansion, and improves the char yield at high temperature with a slightly reduced glass transition temperature. All these differences in macro-properties are attributed to the different crosslinked networks between MPSA/DBA/BDM composites and DBA/BDM resin.

  10. Resin composite restorative materials.

    Science.gov (United States)

    Ilie, N; Hickel, R

    2011-06-01

    This paper surveys the most important developments in resin-based dental composites and focuses on the deficits (e.g. polymerization shrinkage) and strengths of the materials and their clinical implications. Moreover, differences between composite categories, such as hybrid, nanohybrid, microfilled, packable, ormocer-based, silorane-based, polyacid-modified composites (compomers) and flowable composites are highlighted, especially in view of their mechanical behaviour. In addition to the classical dimethacrylate-based composites, special attention is given to alternative monomers, such as siloranes, ormocers or high-molecular-weight dimethacrylate monomers (e.g. dimer acid-based dimethacrylates and tricyclodecane (TCD)-urethane), analysing their advantages, behaviour and abilities. Finally, the paper attempts to establish the needs and wishes of clinicians for further development of resin-based composites. PMID:21564116

  11. System for removing contaminants from plastic resin

    Science.gov (United States)

    Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

    2010-11-23

    A resin recycling system that produces essentially contaminant-free synthetic resin material in an environmentally safe and economical manner. The system includes receiving the resin in container form. A grinder grinds the containers into resin particles. The particles are exposed to a solvent in one or more solvent wash vessels, the solvent contacting the resin particles and substantially removing contaminants on the resin particles. A separator is used to separate the resin particles and the solvent. The resin particles are then placed in solvent removing element where they are exposed to a solvent removing agent which removes any residual solvent remaining on the resin particles after separation.

  12. Contact allergy to epoxy resin

    DEFF Research Database (Denmark)

    Bangsgaard, Nannie; Thyssen, Jacob Pontoppidan; Menné, Torkil; Andersen, Klaus Ejner; Mörtz, Charlotte; Paulsen, Evy; Sommerlund, Mette; Veien, Niels Kren; Laurberg, Grete; Kaaber, Knud; Thormann, Jens; Andersen, Bo Lasthein; Danielsen, Anne; Avnstorp, Christian; Kristensen, Berit; Kristensen, Axel Ove; Vissing, Susanne; Nielsen, Niels Henrik; Johansen, Jeanne Duus

    2012-01-01

    Background. Epoxy resin monomers are strong skin sensitizers that are widely used in industrial sectors. In Denmark, the law stipulates that workers must undergo a course on safe handling of epoxy resins prior to occupational exposure, but the effectiveness of this initiative is largely unknown. Objectives. To evaluate the prevalence of contact allergy to epoxy resin monomer (diglycidyl ether of bisphenol A; MW 340) among patients with suspected contact dermatitis and relate this to occupation a...

  13. Powder Solidifyers of Epoxy Resins

    International Science & Technology Center (ISTC)

    Selection and Investigation of New Powder Metallocomplex Agents as Solidifyer of Epoxy Resins for Refinement of Technological Processes During Manufacturing Electrical Insuletion of Big Electrical Engines

  14. 21 CFR 178.3930 - Terpene resins.

    Science.gov (United States)

    2010-04-01

    ...Drugs 3 2010-04-01 2009-04-01 true Terpene resins. 178.3930 Section 178.3930 Food...Certain Adjuvants and Production Aids § 178.3930 Terpene resins. The terpene resins identified in paragraph (a) of...

  15. Biocompatibility of mesoporous silica nanoparticles.

    Science.gov (United States)

    Asefa, Tewodros; Tao, Zhimin

    2012-11-19

    In this review, recent reports on the biocompatibility of mesoporous silica nanoparticles (MSNs) are reviewed, with special emphasis being paid to the correlations between MSNs' structural and compositional features and their biological effects on various cells and tissues. First, the different synthetic routes used to produce the most common types of MSNs and the various methods employed to functionalize their surfaces are discussed. This is, however, done only briefly because of the focus of the review being the biocompatibility of the materials. Similarly, the biological applications of MSNs in areas such as drug and gene delivery, biocatalysis, bioimaging, and biosensing are briefly introduced. Many examples have also been mentioned about the biological applications of MSNs while discussing the materials' biocompatibility. The cytotoxicity of different types of MSNs and the effects of their various structural characteristics on their biological activities, which are the focus of this review, are then described in detail. In addition, synthetic strategies developed to reduce or eliminate any possible negative biological effects associated with MSNs or to improve their biocompatibility, as necessary, are illustrated. At the same time, recent reports on the interactions between MSNs and various in vivo or in vitro biological systems, plus our opinions and remarks on what the future may hold for this field, are included. PMID:22823891

  16. Properties of the Carboxylate ion exchange resins

    International Nuclear Information System (INIS)

    Weakly acidic, carboxylic resin has been selected, together with strong base anion resins, for water purification at the Forsmark 1 and 2 reactors. For the strong (but not the weak) ion exchange resin the Nuclear Power Inspectorate has given permission to dispose the spent resins in the SFR 1 (the Final Repository for Radioactive Operational Waste). This report gives a review of the carboxylic resins and comes to the conclusion that the resins are very stable and that there should not exist any risks for increased leaching of radionuclides from SFR 1 if these resins are disposed (compared to the strong resins)

  17. Orientation specific deposition of mesoporous particles

    Directory of Open Access Journals (Sweden)

    Tomas Kjellman

    2014-11-01

    Full Text Available We present a protocol for a facile orientation specific deposition of plate-like mesoporous SBA-15 silica particles onto a surface (mesopores oriented normal to surface. A drop of an aqueous dispersion of particles is placed on the surface and water vaporizes under controlled relative humidity. Three requirements are essential for uniform coverage: particle dispersion should not contain aggregates, a weak attraction between particles and surface is needed, and evaporation rate should be low. Aggregates are removed by stirring/sonication. Weak attraction is realized by introducing cationic groups to the surface. Insight into the mechanisms of the so-called coffee stain effect is also provided.

  18. Orientation specific deposition of mesoporous particles

    Science.gov (United States)

    Kjellman, Tomas; Bodén, Niklas; Wennerström, Hâkan; Edler, Karen J.; Alfredsson, Viveka

    2014-11-01

    We present a protocol for a facile orientation specific deposition of plate-like mesoporous SBA-15 silica particles onto a surface (mesopores oriented normal to surface). A drop of an aqueous dispersion of particles is placed on the surface and water vaporizes under controlled relative humidity. Three requirements are essential for uniform coverage: particle dispersion should not contain aggregates, a weak attraction between particles and surface is needed, and evaporation rate should be low. Aggregates are removed by stirring/sonication. Weak attraction is realized by introducing cationic groups to the surface. Insight into the mechanisms of the so-called coffee stain effect is also provided.

  19. Location of laccase in ordered mesoporous materials

    Energy Technology Data Exchange (ETDEWEB)

    Mayoral, Álvaro [Laboratorio de Microscopias Avanzadas, Instituto de Nanociencia de Aragon, Universidad de Zaragoza, Edificio I - D, Mariano Esquillor, 50018 Zaragoza (Spain); Gascón, Victoria; Blanco, Rosa M.; Márquez-Álvarez, Carlos; Díaz, Isabel, E-mail: idiaz@icp.csic.es [Instituto de Catálisis y Petroleoquímica, CSIC, c/Marie Curie 2, 28049 Madrid (Spain)

    2014-11-01

    The functionalization with amine groups was developed on the SBA-15, and its effect in the laccase immobilization was compared with that of a Periodic Mesoporous Aminosilica. A method to encapsulate the laccase in situ has now been developed. In this work, spherical aberration (C{sub s}) corrected scanning transmission electron microscopy combined with high angle annular dark field detector and electron energy loss spectroscopy were applied to identify the exact location of the enzyme in the matrix formed by the ordered mesoporous solids.

  20. Mesoporous Silica and Composite Nanostructures for Theranostics

    Directory of Open Access Journals (Sweden)

    Khlebtsov B.N.

    2013-09-01

    Full Text Available We discus methods for fabrication of silica and composite nanoparticles, which can be used in various biomedical applications. The most promising types of such nanostructures are hollow silica nanosheres, silica coated plasmon-resonant nanoparticles (gold nanorods and gold-silver nanocages and nanorattles. Mesoporous silica shell can be doped by desirable targeting molecules. Here we present the results of formation of nanocomposites composed of gold nanorods and double-layer silica shell. The secondary mesoporous silica shell is doped with a photosensitizer (hematoporphyrine in our case. We demonstate some of promising theranostics applications of these nanocomposites for bioimaging and in vivo therapy of tumors.

  1. Unidirectional self-assembly of soft templated mesoporous carbons by zone annealing

    Science.gov (United States)

    Xue, Jiachen; Singh, Gurpreet; Qiang, Zhe; Karim, Alamgir; Vogt, Bryan D.

    2013-08-01

    Surfactant or block copolymer-templated mesoporous films have been extensively explored, but achieving mesostructure coherence and unidirectional orientation over macroscopic dimensions has remained quite challenging for these self-assembled systems. Here, we extend the concepts associated with zone refinement of crystalline materials to soft templated mesoporous carbon films based on the cooperative assembly of commercial non-ionic surfactants (block copolymers) and phenolic resin oligomers (resol) to provide macroscopic alignment of both cubic (FDU-16) and hexagonal (FDU-15) mesostructures. The average orientation of these mesophases is determined from rotation grazing incidence small angle X-ray scattering (GISAXS) measurements. For FDU-15 templated by Pluronic P123, the orientation factor for the zone-annealed film is 0.98 based on the average of the second Legendre polynomial, but this orientation deteriorates significantly during carbonization. Notably, a thermal stabilization step following zone annealing preserves the orientation of the mesostructure during carbonization. The orientation factor for an isotropic cubic structure (FDU-16 templated by Pluronic F127) is only 0.48 (based on the 111 reflection with incident angle 0.15°) for the same zone annealing protocol, but this illustrates the versatility of zone annealing to different mesostructures. Unexpectedly, zone annealing of FDU-15 templated by Pluronic F127 leads to stabilization of the mesostructure through carbonization, whereas this structure collapses fully during carbonization even after extended oven annealing; despite no clear macroscopic orientation of the cylindrical mesostructure from zone annealing. Thermal zone annealing provides a simple methodology to produce highly ordered and macroscopically oriented stable mesoporous carbon films, but the efficacy is strongly tied to the mobility of the template during the zone annealing.Surfactant or block copolymer-templated mesoporous films have been extensively explored, but achieving mesostructure coherence and unidirectional orientation over macroscopic dimensions has remained quite challenging for these self-assembled systems. Here, we extend the concepts associated with zone refinement of crystalline materials to soft templated mesoporous carbon films based on the cooperative assembly of commercial non-ionic surfactants (block copolymers) and phenolic resin oligomers (resol) to provide macroscopic alignment of both cubic (FDU-16) and hexagonal (FDU-15) mesostructures. The average orientation of these mesophases is determined from rotation grazing incidence small angle X-ray scattering (GISAXS) measurements. For FDU-15 templated by Pluronic P123, the orientation factor for the zone-annealed film is 0.98 based on the average of the second Legendre polynomial, but this orientation deteriorates significantly during carbonization. Notably, a thermal stabilization step following zone annealing preserves the orientation of the mesostructure during carbonization. The orientation factor for an isotropic cubic structure (FDU-16 templated by Pluronic F127) is only 0.48 (based on the 111 reflection with incident angle 0.15°) for the same zone annealing protocol, but this illustrates the versatility of zone annealing to different mesostructures. Unexpectedly, zone annealing of FDU-15 templated by Pluronic F127 leads to stabilization of the mesostructure through carbonization, whereas this structure collapses fully during carbonization even after extended oven annealing; despite no clear macroscopic orientation of the cylindrical mesostructure from zone annealing. Thermal zone annealing provides a simple methodology to produce highly ordered and macroscopically oriented stable mesoporous carbon films, but the efficacy is strongly tied to the mobility of the template during the zone annealing. Electronic supplementary information (ESI) available: GISAXS profiles for the FDU-15-F127 at ? = 0° and ? = 90° is included along with 2D GISAXS data for all azimuthal data associated with FDU-15-P123 to illustrate th

  2. Large-scale roll-to-roll fabrication of ordered mesoporous materials using resol-assisted cooperative assembly.

    Science.gov (United States)

    Qiang, Zhe; Guo, Yuanhao; Liu, Hao; Cheng, Stephen Z D; Cakmak, Miko; Cavicchi, Kevin A; Vogt, Bryan D

    2015-02-25

    Roll-to-roll (R2R) processing enables the rapid fabrication of large-area sheets of cooperatively assembled materials for production of mesoporous materials. Evaporation induced self-assembly of a nonionic surfactant (Pluronic F127) with sol-gel precursors and phenolic resin oligomers (resol) produce highly ordered mesostructures for a variety of chemistries including silica, titania, and tin oxide. The cast thick (>200 ?m) film can be easily delaminated from the carrier substrate (polyethylene terephthalate, PET) after cross-linking the resol to produce meter-long self-assembled sheets. The surface areas of these mesoporous materials range from 240 m(2)/g to >1650 m(2)/g with these areas for each material comparing favorably with prior reports in the literature. These R2R methods provide a facile route to the scalable production of kilograms of a wide variety of ordered mesoporous materials that have shown potential for a wide variety of applications with small-batch syntheses. PMID:25635350

  3. Preparation and characterization of multifunctional magnetic mesoporous calcium silicate materials

    Science.gov (United States)

    Zhang, Jianhua; Zhu, Yufang; Li, Jie; Zhu, Min; Tao, Cuilian; Hanagata, Nobutaka

    2013-10-01

    We have prepared multifunctional magnetic mesoporous Fe-CaSiO3 materials using triblock copolymer (P123) as a structure-directing agent. The effects of Fe substitution on the mesoporous structure, in vitro bioactivity, magnetic heating ability and drug delivery property of mesoporous CaSiO3 materials were investigated. Mesoporous Fe-CaSiO3 materials had similar mesoporous channels (5-6 nm) with different Fe substitution. When 5 and 10% Fe were substituted for Ca in mesoporous CaSiO3 materials, mesoporous Fe-CaSiO3 materials still showed good apatite-formation ability and had no cytotoxic effect on osteoblast-like MC3T3-E1 cells evaluated by the elution cell culture assay. On the other hand, mesoporous Fe-CaSiO3 materials could generate heat to raise the temperature of the surrounding environment in an alternating magnetic field due to their superparamagnetic property. When we use gentamicin (GS) as a model drug, mesoporous Fe-CaSiO3 materials release GS in a sustained manner. Therefore, magnetic mesoporous Fe-CaSiO3 materials would be a promising multifunctional platform with bone regeneration, local drug delivery and magnetic hyperthermia.

  4. Preparation and characterization of multifunctional magnetic mesoporous calcium silicate materials

    International Nuclear Information System (INIS)

    We have prepared multifunctional magnetic mesoporous Fe–CaSiO3 materials using triblock copolymer (P123) as a structure-directing agent. The effects of Fe substitution on the mesoporous structure, in vitro bioactivity, magnetic heating ability and drug delivery property of mesoporous CaSiO3 materials were investigated. Mesoporous Fe–CaSiO3 materials had similar mesoporous channels (5–6 nm) with different Fe substitution. When 5 and 10% Fe were substituted for Ca in mesoporous CaSiO3 materials, mesoporous Fe–CaSiO3 materials still showed good apatite-formation ability and had no cytotoxic effect on osteoblast-like MC3T3-E1 cells evaluated by the elution cell culture assay. On the other hand, mesoporous Fe–CaSiO3 materials could generate heat to raise the temperature of the surrounding environment in an alternating magnetic field due to their superparamagnetic property. When we use gentamicin (GS) as a model drug, mesoporous Fe–CaSiO3 materials release GS in a sustained manner. Therefore, magnetic mesoporous Fe–CaSiO3 materials would be a promising multifunctional platform with bone regeneration, local drug delivery and magnetic hyperthermia. (paper)

  5. Porosity of micro/mesoporous composites.

    Czech Academy of Sciences Publication Activity Database

    Fojtíková, P.; Mintova, S.; ?ejka, Ji?í; Žilková, Nad?žda; Zukal, Arnošt

    2006-01-01

    Ro?. 92, 1-3 (2006), s. 154-160. ISSN 1387-1811 R&D Projects: GA ?R GA203/05/0197; GA MPO FT-TA/040 Institutional research plan: CEZ:AV0Z40400503 Keywords : micro/mesoporous composite * nitrogen adsorption * porous structure development Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.796, year: 2006

  6. Mesoporous Transition Metal Oxides for Supercapacitors

    Directory of Open Access Journals (Sweden)

    Yan Wang

    2015-10-01

    Full Text Available Recently, transition metal oxides, such as ruthenium oxide (RuO2, manganese dioxide (MnO2, nickel oxides (NiO and cobalt oxide (Co3O4, have been widely investigated as electrode materials for pseudo-capacitors. In particular, these metal oxides with mesoporous structures have become very hot nanomaterials in the field of supercapacitors owing to their large specific surface areas and suitable pore size distributions. The high specific capacities of these mesoporous metal oxides are resulted from the effective contacts between electrode materials and electrolytes as well as fast transportation of ions and electrons in the bulk of electrode and at the interface of electrode and electrolyte. During the past decade, many achievements on mesoporous transition metal oxides have been made. In this mini-review, we select several typical nanomaterials, such as RuO2, MnO2, NiO, Co3O4 and nickel cobaltite (NiCo2O4, and briefly summarize the recent research progress of these mesoporous transition metal oxides-based electrodes in the field of supercapacitors.

  7. Chromatography resin support

    Science.gov (United States)

    Dobos, James G. (North Augusta, SC)

    2002-01-01

    An apparatus and method of using an improved chromatography resin support is disclosed. The chromatography support platform is provided by a stainless steel hollow cylinder adapted for being inserted into a chromatography column. An exterior wall of the stainless steel cylinder defines a groove for carrying therein an "O"-ring. The upper surface of the stainless steel column is covered by a fine stainless steel mesh welded to the edges of the stainless steel cylinder. When placed upon a receiving ledge defined within a chromatography column, the "O"-ring provides a fluid tight seal with the inner edge wall of the chromatography cylinder. The stainless steel mesh supports the chromatography matrix and provides a back flushable support which is economical and simple to construct.

  8. Functionalized bimodal mesoporous silicas as carriers for controlled aspirin delivery

    Science.gov (United States)

    Gao, Lin; Sun, Jihong; Li, Yuzhen

    2011-08-01

    The bimodal mesoporous silica modified with 3-aminopropyltriethoxysilane was performed as the aspirin carrier. The samples' structure, drug loading and release profiles were characterized with X-ray diffraction, scanning electron microscopy, N 2 adsorption and desorption, Fourier transform infrared spectroscopy, TG analysis, elemental analysis and UV-spectrophotometer. For further exploring the effects of the bimodal mesopores on the drug delivery behavior, the unimodal mesoporous material MCM-41 was also modified as the aspirin carrier. Meantime, Korsmeyer-Peppas equation ft= ktn was employed to analyze the dissolution data in details. It is indicated that the bimodal mesopores are beneficial for unrestricted drug molecules diffusing and therefore lead to a higher loading and faster releasing than that of MCM-41. The results show that the aspirin delivery properties are influenced considerably by the mesoporous matrix, whereas the large pore of bimodal mesoporous silica is the key point for the improved controlled-release properties.

  9. Phenolic resin-based porous carbons for adsorption and energy storage applications

    Science.gov (United States)

    Wickramaratne, Nilantha P.

    The main objective of this dissertation research is to develop phenolic resin based carbon materials for range of applications by soft-templating and Stober-like synthesis strategies. Applications Studied in this dissertation are adsorption of CO2, bio-molecular and heavy metal ions, and energy storage devices. Based on that, our goal is to design carbon materials with desired pore structure, high surface area, graphitic domains, incorporated metal nanoparticles, and specific organic groups and heteroatoms. In this dissertation the organic-organic self-assembly of phenolic resins and triblock copolymers under acidic conditions will be used to obtain mesoporous carbons/carbon composites and Stober-like synthesis involving phenolic resins under basic condition will be used to prepare polymer/carbon particles and their composites. The structure of this dissertation consists of an introductory chapter (Chapter 1) discussing the general synthesis of carbon materials, particularly the soft-templating strategy and Stober-like carbon synthesis. Also, Chapter 1 includes a brief outline of applications namely adsorption of CO2, biomolecule and heavy metal ions, and supercapacitors. Chapter 2 discusses the techniques used for characterization of the carbon materials studied. This chapter starts with nitrogen adsorption analysis, which is used to measure the specific surface area, pore volume, distribution of pore sizes, and pore width. In addition to nitrogen adsorption, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution thermogravimetric analysis (HR-TGA), cyclic voltammetry (CV) and CHNS elemental analysis (EA) are mentioned too. Chapter 3 is focused on carbon materials for CO2 adsorption. There are different types of porous solid materials such as silicate, MOFs, carbons, and zeolites studied for CO2 adsorption. However, the carbon based materials are considered to be the best candidates for CO 2 adsorption to the industrial point of view. So far, carbons with high surface area and nitrogen content have been vastly studied. Also, there are several reports showing the importance of pore size towards CO2 adsorption at ambient conditions. In the case of nitrogen containing carbons, it was shown that the incorporation of nitrogen into carbon matrix is a challenging task. In chapter 3, we discussed how to improve the surface area and pore size distribution of phenolic resin-based carbons to obtain optimum CO 2 adsorption capacities at ambient conditions. The chemical and physical activation of polymer/carbon particles is used to generate necessary physical properties of the final carbons, which display unprecedented CO2 adsorption capacities at ambient conditions. Moreover, the modified Stober-like methods are used for the synthesis of nitrogen containing carbon particles. These facile synthesis methods afford highly porous nitrogen containing carbons with comparatively high CO2 adsorption capacities at ambient conditions. Chapter 4 begins with synthesis of ultra large mesoporous carbons using (ethylene oxide)38 (butylene oxide)46 (ethylene oxide) 38 triblock copolymer as a soft template and phenolic resins as the carbon precursors. Even though, there are many reports dealing with the synthesis of mesoporous silica with large pores for bio-molucular adsorption their high cost discourage them to use in industrial applications. However, cheap mesoporous carbons with large pores (>15 nm) are potential materials for bio-molecular adsorption on large scale. The first part of chapter 4 is demonstrates the synthesis of mesoporous carbons with ultra large pores for bio-molecular adsorption. Lysozyme was selected as a model biomolecule for adsorption processes. The second part of Chapter 4 is focused on functionalized polymer spheres for heavy metal ions adsorption. It is shown that the synthesis of functionalized polymer spheres can be achieved by using modified Stober method; the reacting spheres show very high Cu2+ ion adsorption capacities. Next, Chapter 5 is devoted to carbon materials for superca

  10. Mesoporous Molecular Sieves as Supports for Metathesis Catalysts

    Science.gov (United States)

    Balcar, Hynek; Cejka, Jirí

    Mesoporous molecular sieves represent a new family of inorganic oxides with regular nanostructure, large surface areas, large void volumes, and narrow pore size distribution of mesopores. These materials offer new possibilities for designing highly active and selective catalysts for olefin metathesis and metathesis polymerization. Siliceous sieves MCM-41, MCM-48, SBA-15, and organized mesoporous alumina (OMA) were used as supports for preparation of new molybdenum and rhenium oxide catalysts, as well as for heterogenization of well-defined homogeneous catalysts.

  11. Aluminum-rich mesoporous MFI - type zeolite single crystals

    DEFF Research Database (Denmark)

    Kustova, Marina; Kustov, Arkadii; Christensen, Christina Hviid

    2005-01-01

    Zeolitcs are crystalline materials, which are widely used as solid acid catalysts and supports in many industrial processes. Recently, mesoporous MFI-type zeolite single crystals were synthesized by use of carbon particles as a mesopore template and sodium aluminate as the aluminum Source. With this technique, only zeolites with relatively low Al contents were reported (Si/Al ratio about 100). In this work, the preparation of aluminum-rich mesoporous MFI-type zeolite single crystals (Si/Al simil...

  12. Mesoporous zeolite and zeotype single crystals synthesized in fluoride media

    DEFF Research Database (Denmark)

    Egeblad, Kresten; Kustova, Marina; Klitgaard, Søren Kegnæs; Zhu, Kake; Christensen, Claus H.

    2007-01-01

    We report the synthesis and characterization of a series of new mesoporous zeolite and zeotype materials made available by combining new and improved procedures for directly introducing carbon into reaction mixtures with the fluoride route for conventional zeolite synthesis. The mesoporous materials were all prepared by hydrothermal crystallization of gels adsorbed on carbon matrices which were subsequently removed by combustion. The procedures presented here resulted in mesoporous zeolite and z...

  13. Bending characteristics of resin concretes

    Scientific Electronic Library Online (English)

    Maria Cristina Santos, Ribeiro; Cassilda Maria Lopes, Tavares; Miguel, Figueiredo; António Joaquim Mendes, Ferreira; António Augusto, Fernandes.

    2003-06-01

    Full Text Available In this research work the influence of composition and curing conditions in bending strength of polyester and epoxy concrete is analyzed. Various mixtures of resin and aggregates were considered in view of an optimal combination. The Taguchi methodology was applied in order to reduce the number of t [...] ests, and in order to evaluate the influence of various parameters in concrete properties. This methodology is very useful for the planning of experiments. Test results, analyzed by this methodology, shown that the most significant factors affecting bending strength properties of resin concretes are the type of resin, resin content and charge content. An optimal formulation leading to a maximum bending strength was achieved in terms of material parameters.

  14. Bending characteristics of resin concretes

    Directory of Open Access Journals (Sweden)

    Ribeiro Maria Cristina Santos

    2003-01-01

    Full Text Available In this research work the influence of composition and curing conditions in bending strength of polyester and epoxy concrete is analyzed. Various mixtures of resin and aggregates were considered in view of an optimal combination. The Taguchi methodology was applied in order to reduce the number of tests, and in order to evaluate the influence of various parameters in concrete properties. This methodology is very useful for the planning of experiments. Test results, analyzed by this methodology, shown that the most significant factors affecting bending strength properties of resin concretes are the type of resin, resin content and charge content. An optimal formulation leading to a maximum bending strength was achieved in terms of material parameters.

  15. Preparation of superhydrophilic mesoporous SiO2 thin films

    Science.gov (United States)

    Chen, Peiyi; Hu, Yun; Wei, Chaohai

    2012-03-01

    Using a simple sol-gel/spin-coating method, mesoporous SiO2 thin films were prepared on glass slides. All of the prepared thin films were colorless and transparent as original glass substrates. XRD and TEM measurements revealed that the prepared SiO2 thin films coated 3-12 times possess hexagonal mesoporous structure. The mesoporous SiO2 thin films performed the superhydrophilicity and antifogging property in the absence of UV light irradiation. The results suggested that the appropriate film thickness and mesoporous structures can improve the surface superhydrophilic behavior of SiO2 thin films.

  16. Preparation of superhydrophilic mesoporous SiO2 thin films

    International Nuclear Information System (INIS)

    Using a simple sol-gel/spin-coating method, mesoporous SiO2 thin films were prepared on glass slides. All of the prepared thin films were colorless and transparent as original glass substrates. XRD and TEM measurements revealed that the prepared SiO2 thin films coated 3-12 times possess hexagonal mesoporous structure. The mesoporous SiO2 thin films performed the superhydrophilicity and antifogging property in the absence of UV light irradiation. The results suggested that the appropriate film thickness and mesoporous structures can improve the surface superhydrophilic behavior of SiO2 thin films.

  17. Liquid monobenzoxazine based resin system

    Energy Technology Data Exchange (ETDEWEB)

    Tietze, Roger; Nguyen, Yen-Loan; Bryant, Mark

    2014-10-07

    The present invention provides a liquid resin system including a liquid monobenzoxazine monomer and a non-glycidyl epoxy compound, wherein the weight ratio of the monobenzoxazine monomer to the non-glycidyl epoxy compound is in a range of about 25:75 to about 60:40. The liquid resin system exhibits a low viscosity and exceptional stability over an extended period of time making its use in a variety of composite manufacturing methods highly advantageous.

  18. Bulk-Fill Resin Composites

    DEFF Research Database (Denmark)

    Benetti, Ar; Havndrup-Pedersen, C; Honoré, D; Pedersen, Mk; Pallesen, U; Benetti, Ana Raquel

    2015-01-01

    SUMMARY The bulk-filling of deep, wide dental cavities is faster and easier than traditional incremental restoration. However, the extent of cure at the bottom of the restoration should be carefully examined in combination with the polymerization contraction and gap formation that occur during the restorative procedure. The aim of this study, therefore, was to compare the depth of cure, polymerization contraction, and gap formation in bulk-fill resin composites with those of a conventional resin...

  19. Concrete rehabilitation using epoxy resins

    OpenAIRE

    Silva, Luís; Aguiar, J. L. Barroso de

    2010-01-01

    The use of polymeric materials in civil construction makes possible original bonding processes because they have good adhesion. In this paper the bond between fresh/hardened concrete was made using epoxy resins in aqueous solution. Also the incorporation of one filler in the epoxy resins was analyzed. This study had two phases. n the first were conducted two shear tests - slant and direct. In the second phase were produced concrete with different strength classes by varying the ratio W/C - 0....

  20. 40 CFR 721.7220 - Polymer of substituted phenol, formaldehyde, epichlorohydrin, and disubstituted benzene.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polymer of substituted phenol... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.7220 Polymer of substituted phenol... subject to reporting. (1) The chemical substance identified generically as polymer of substituted...

  1. Synthesis and Properties of Phloroglucinol-Phenol-Formaldehyde Carbon Aerogels and Xerogels.

    Czech Academy of Sciences Publication Activity Database

    Jirglová, Hana; Pérez-Cadenas, A. F.; Maldonado-Hódar, F. J.

    2009-01-01

    Ro?. 25, ?. 4 (2009), s. 2461-2466. ISSN 0743-7463 Institutional research plan: CEZ:AV0Z40400503 Keywords : organic aerogels * immersion calorimetry * activated carbon Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.898, year: 2009

  2. Molecular sieve behaviour of carbon aerogels and xerogels prepared from phloroglucinol-phenol-formaldehyde polymerization.

    Czech Academy of Sciences Publication Activity Database

    Jirglová, Hana; Pérez-Cadenas, A. F.; Hódar, F. J. M.

    Biarritz : SARL VACANCES SUD TERRES BASQUES, 2009, ID 153. [Carbon 09. Biarritz (FR), 14.06.2009-19.06.2009] Institutional research plan: CEZ:AV0Z40400503 Keywords : polymerization * molecular sieves * carbon aerogels Subject RIV: CF - Physical ; Theoretical Chemistry

  3. Acylation Reactions over Zeolites and Mesoporous Catalysts.

    Czech Academy of Sciences Publication Activity Database

    Voláková, Martina; Vitvarová, Dana; ?ejka, Ji?í

    2009-01-01

    Ro?. 2, ?. 6 (2009), s. 486-499. ISSN 1864-5631 R&D Projects: GA ?R GA104/07/0383; GA ?R GD203/08/H032; GA MPO FT-TA5/005 Institutional research plan: CEZ:AV0Z40400503 Keywords : acylation * ketones * mesoporous materials * shape-selectivity * zeolites Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.767, year: 2009

  4. 46 CFR Table I to Part 150 - Alphabetical List of Cargoes

    Science.gov (United States)

    2010-10-01

    ... Butyl methyl ketone, see Methyl butyl ketone MBK Butyl phenol, Formaldehyde resin in Xylene 32 n-Butyl... chain alkyl salicylate (C13+) 34 CAK Calcium long chain alkyl phenolic amine (C8-C40) 9 CPQ Calcium...) 43 DRM Epichlorohydrin 17 1 EPC Epoxy resin 18 ETBE, see Ethyl tert-butyl ether EBE Ethane 31 1...

  5. Mesoporous metal catalysts formed by ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Schaeferhans, Jana; Pazos Perez, Nicolas; Andreeva, Daria [Physikalische Chemie II, Universitaet Bayreuth (Germany)

    2010-07-01

    We study the ultrasound-driven formation of mesoporous metal sponges. The collapse of acoustic cavitations leads to very high temperatures and pressures on very short scales. Therefore, structures may be formed and quenched far from equilibrium. Mechanism of metal modification by ultrasound is complex and involves a variety of aspects. We propose that modification of metal particles and formation of mesoporous inner structures can be achieved due to thermal etching of metals by ultrasound stimulated high speed jets of liquid. Simultaneously, oxidation of metal surfaces by free radicals produced in water during cavitation stabilizes developed metal structures. Duration and intensity of the ultrasonication treatment is able to control the structure and morphology of metal sponges. We expect that this approach to the formation of nanoscale composite sponges is universal and opens perspective for a whole new class of catalytic materials that can be prepared in a one-step process. The developed method makes it possible to control the sponge morphology and can be used for formation of modern types of catalysts. For example, the sonication technique allows to combine the fabrication of mesoporous support and distribution of metal (Cu, Pd, Au, Pt etc.) nanoparticles in its pores into a single step.

  6. Immobilization of Methyltrioxorhenium on Mesoporous Aluminosilicate Materials

    Directory of Open Access Journals (Sweden)

    Martina Stekrova

    2014-03-01

    Full Text Available The presented report focuses on an in-depth detailed characterization of immobilized methyltrioxorhenium (MTO, giving catalysts with a wide spectra of utilization. The range of mesoporous materials with different SiO2/Al2O3 ratios, namely mesoporous alumina (MA, aluminosilicates type Siral (with Al content 60%–90% and MCM-41, were used as supports for immobilization of MTO. The tested support materials (aluminous/siliceous exhibited high surface area, well-defined regular structure and narrow pore size distribution of mesopores, and therefore represent excellent supports for the active components. Some of the supports were modified by zinc chloride in order to obtain catalysts with higher activities for instance in metathesis reactions. The immobilization of MTO was optimized using these supports and it was successful using all supports. The success of the immobilization of MTO and the properties of the prepared heterogeneous catalysts were characterized using X-ray Fluorescence (XRF, atomic absorption spectroscopy (AAS, X-ray powder diffraction (XRD, scanning electron microscopy (SEM, physical adsorption of N2, ultraviolet-visible spectroscopy (UV-Vis, infrared spectroscopy (FTIR, Fourier Transform Infrared Spectroscopy (FTIR using pyridine as a probe molecule and X-ray photoelectron spectroscopy (XPS. Furthermore, the catalytic activity of the immobilized MTO on the tested supports was demonstrated on metathesis reactions of various substrates.

  7. OIL PALM TRUNK POLYMER COMPOSITE: MORPHOLOGY, WATER ABSORPTION, AND THICKNESS SWELLING BEHAVIOURS

    OpenAIRE

    C. K. Abdullah,; M. Jawaid,; H. P. S. Abdul Khalil,; A. Zaidon,; A. Hadiyane

    2012-01-01

    In this research, impregnated oil palm trunks (OPT) and polymer composites were prepared from a combination of dried oil palm trunks with phenol formaldehyde (PF) and urea formaldehyde (UF) resin in different resin percentages using an impregnation method. Time of impregnation was a parameter used to control the percentage of resin content in the oil palm trunks. These studies investigated the effect of resin content and types of resin on the physical properties of impregnated OPT. Water abso...

  8. Mesoporous zeolite and zeotype single crystals synthesized in fluoride media

    DEFF Research Database (Denmark)

    Egeblad, Kresten; Kustova, Marina

    2007-01-01

    We report the synthesis and characterization of a series of new mesoporous zeolite and zeotype materials made available by combining new and improved procedures for directly introducing carbon into reaction mixtures with the fluoride route for conventional zeolite synthesis. The mesoporous materials were all prepared by hydrothermal crystallization of gels adsorbed on carbon matrices which were subsequently removed by combustion. The procedures presented here resulted in mesoporous zeolite and zeotypes materials with MFI, MEL, BEA, AFI and CHA framework structures. All samples were characterized by XRPD, SEM, TEM and N-2 physisorption measurements. For the zeolite materials it A as found that mesoporous MFI and MEL structured single crystals could indeed be crystallized from fluoride media using an improved carbon-templating approach. More importantly, it was found that mesoporous BEA-type single crystals could be crystallized from fluoride media by a newly developed procedure presented here. Thus, we here present the only known route to mesoporous BEA-type single crystals, since crystallization of this framework structure from basic media is known to give only nanosized crystals as opposed to mesoporous single crystals. For the zeotype materials it was found that highly crystalline mesoporous materials of AFI and CHA structure types could be synthesized using a newly developed procedure. (c) 2006 Elsevier Inc. All rights reserved.

  9. Generalized synthesis of mesoporous shells on zeolite crystals

    KAUST Repository

    Han, Yu

    2010-12-30

    A simple and generalized synthetic approach is developed for creating mesoporous shells on zeolite crystals. This method allows for the tailoring of thickness, pore size, and composition of the mesoporous shell, and can be applied to zeolites of various structures, compositions, and crystal sizes. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Morphology control of ordered mesoporous carbons for high capacity lithium sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, Joerg David

    2011-06-07

    The focus of this thesis concerns the morphology control of ordered mesoporous carbon (OMC) materials. Ordered mesoporous carbons with diverse morphologies, that are thin films, fibers - embedded in anodic alumina membranes and free-standing - or spherical nanoparticles, have been successfully prepared by soft-templating procedures. The mechanisms of structure formation and processing were investigated with in-situ SAXS measurements and their application in high capacity lithium-sulfur batteries was successfully tested in cooperation with Guang He and Linda Nazar from the University of Waterloo in Canada. The Li-S batteries receive increasing attention due to their high theoretical energy density which is 3 to 5 times higher than from lithium-ion batteries. For this type of battery the specific pore volume is crucial for the content of the active component (sulfur) in the cathode and therefore correlates with the capacity and gravimetric energy density of the battery. At first, mesoporous thin films with 2D-hexagonal structure were obtained through organic-organic self-assembly of a preformed oligomeric resol precursor and the triblock copolymer template Pluronic P123. The formation of a condensed-wall material through thermopolymerization of the precursor oligomers resulted in mesostructured phenolic resin films. Subsequent decomposition of the surfactant and partial carbonization were achieved through thermal treatment in inert atmosphere. The films were crack-free with tunable homogenous thicknesses, and showed either 2D-hexagonal or lamellar mesostructure. An additional, yet unknown 3D-mesostructure was also found. In the second part, cubic and circular hexagonal mesoporous carbon phases in the confined environment of tubular anodic alumina membrane (AAM) pores were obtained by self-assembly of the mentioned resol precursor and the triblock copolymer templates Pluronic F127 or P123, respectively. Casting and solvent-evaporation were also followed by thermopolymerization, thermal decomposition of the surfactant and carbonization through thermal treatment at temperatures up to 1000 C in an inert atmosphere. For both structures the AAM pores were completely filled and no shrinkage was observed, due to strong adhesion of the carbon wall material to the AAM pore walls. As a consequence of this restricted shrinkage effect, the mesophase system stayed almost constant even after thermal treatment at 1000 C, and pore sizes of up to 20 nm were obtained. In the third part, the aforementioned mesoporous films and embedded fibers in AAMs were further investigated concerning structure formation and carbonization in an in-situ SAXS study. The in-situ measurements revealed that for both systems the structure formation occurs during the thermopolymerization step. Therefore the process of structure formation differs significantly from the known evaporation-induced self-assembly (EISA) and may rather be viewed as thermally-induced self-assembly. As a result, the structural evolution strongly depends on the chosen temperature, which controls both the rate of the mesostructure formation and the spatial dimensions of the resulting mesophase. In the fourth part the syntheses recipes for AAMs were applied on a presynthesized silica template for synthesis of freestanding mesoporous carbon nanofibers. The syntheses start with casting of carbon nanofibers with a silica precursor solution leading to a porous silica template after calcination with tubular pores mimicking the initial carbon nanofibers. A synthesis concept using triconstituent coassembly of resol, tetraethylorthosilicate as additional silica precursor and Pluronic F127 was applied here. The silica from the additional precursor was found to be beneficial, due to reduced shrinkage and created additional porosity after etching it. Those OMC nanofibers therefore exhibited a very large surface area and a high pore volume of 2486 m{sup 2}/g and 2.06 cm{sup 3}/g, respectively. Due to their extremely high porosity values, those fibers were successfully applied as sulfur host and electrode

  11. 7 CFR 319.37-8 - Growing media.

    Science.gov (United States)

    2010-01-01

    ...peat, perlite, phenol formaldehyde, plastic particles...polystyrene, polyethylene, phenol formaldehyde, or ureaformaldehyde: ...polystyrene, polyethylene, phenol formaldehyde, ureaformaldehyde; ...Convention of the United Nations' Food and Agriculture...

  12. Iron oxide nanoparticles stabilized inside highly ordered mesoporous silica

    Indian Academy of Sciences (India)

    A Bhaumik; S Samanta; N K Mal

    2005-11-01

    Nanosized iron oxide, a moderately large band-gap semiconductor and an essential component of optoelectrical and magnetic devices, has been prepared successfully inside the restricted internal pores of mesoporous silica material through in-situ reduction during impregnation. The samples were characterized by powder XRD, TEM, SEM/EDS, N2 adsorption, FT-IR and UV–visible spectroscopies. Characterization data indicated well-dispersed isolated nanoclusters of (Fe2O3)$_{n}$, within the internal surface of 2D-hexagonal mesoporous silica structure. No occluded Fe/Fe2O3 crystallites were observed at the external surface of the mesoporous silica nanocomposites. Inorganic mesoporous host, such as hydrophilic silica in the pore walls, directs a physical constraint necessary to prevent the creation of large Fe2O3 agglomerates and enables the formation of nanosized Fe2O3 particles inside the mesopore.

  13. Synthesis and catalytic applications of combined zeolitic/mesoporous materials

    Directory of Open Access Journals (Sweden)

    Jarian Vernimmen

    2011-11-01

    Full Text Available In the last decade, research concerning nanoporous siliceous materials has been focused on mesoporous materials with intrinsic zeolitic features. These materials are thought to be superior, because they are able to combine (i the enhanced diffusion and accessibility for larger molecules and viscous fluids typical of mesoporous materials with (ii the remarkable stability, catalytic activity and selectivity of zeolites. This review gives an overview of the state of the art concerning combined zeolitic/mesoporous materials. Focus is put on the synthesis and the applications of the combined zeolitic/mesoporous materials. The different synthesis approaches and formation mechanisms leading to these materials are comprehensively discussed and compared. Moreover, Ti-containing nanoporous materials as redox catalysts are discussed to illustrate a potential implementation of combined zeolitic/mesoporous materials.

  14. Aluminum-rich mesoporous MFI - type zeolite single crystals

    DEFF Research Database (Denmark)

    Kustova, Marina; Kustov, Arkadii

    2005-01-01

    Zeolitcs are crystalline materials, which are widely used as solid acid catalysts and supports in many industrial processes. Recently, mesoporous MFI-type zeolite single crystals were synthesized by use of carbon particles as a mesopore template and sodium aluminate as the aluminum Source. With this technique, only zeolites with relatively low Al contents were reported (Si/Al ratio about 100). In this work, the preparation of aluminum-rich mesoporous MFI-type zeolite single crystals (Si/Al similar to 16-50) using aluminum isopropoxide as the aluminum Source is reported for the first time. All samples are characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), ammonia temperature programmed desorption (NH3-TPD), and N-2 adsorption measurements. The obtained zeolites combine the high crystallinity and the characteristic micropores of zeolites with an intracrystalline mesopore system having mesopore volumes varying between 0.37-0.40 cm(3)/g.

  15. Crystals in crystals : Nanocrystals within mesoporous zeolite single crystals

    DEFF Research Database (Denmark)

    Christensen, Claus H.; Schmidt, I.

    2005-01-01

    A major factor governing the performance of catalytically active particles supported on a zeolite carrier is the degree of dispersion. It is shown that the introduction of noncrystallographic mesopores into zeolite single crystals (silicalite-1, ZSM-5) may increase the degree of particle dispersion. As representative examples, a metal (Pt), an alloy (PtSn), and a metal carbide (beta-Mo2C) were supported on conventional and mesoporous zeolite carriers, respectively, and the degree of particle dispersion was compared by TEM imaging. On conventional zeolites, the supported material aggregated on the outer surface of the zeolite particles, particularly after thermal treatment. When using mesoporous zeolites, the particles were evenly distributed throughout the mesopore system of the zeolitic support, even after calcination, leading to nanocrystals within mesoporous zeolite single crystals.

  16. [Study on absorbing volatile oil with mesoporous carbon].

    Science.gov (United States)

    Yan, Hong-mei; Jia, Xiao-bin; Zhang, Zhen-hai; Sun, E; Yang Nan

    2014-11-01

    Clove oil and turmeric oil were absorbed by mesoporous carbon. The absorption ratio of mesoporous carbon to volatile oil was optimized with the eugenol yield and curcumol yield as criteria Curing powder was characterized by scanning electron microscopy (SEM) and differential scanning calorietry (DSC). The effects of mesoporous carbon on dissolution in vitro and thermal stability of active components were studied. They reached high adsorption rate when the absorption ratio of mesoporous carbon to volatile oil was 1:1. When volatile oil was absorbed, dissolution rate of active components had a little improvement and their thermal stability improved after volatile oil was absorbed by the loss rate decreasing more than 50%. Absorbing herbal volatile oil with mesoporous carbon deserves further studying. PMID:25850263

  17. Selectivity of ion exchangers in extracting cesium and rubidium from alkaline solutions

    Science.gov (United States)

    Shelkovnikova, L. A.; Kargov, S. I.; Gavlina, O. T.; Ivanov, V. A.; Al'tshuler, G. N.

    2013-01-01

    We compare the ion exchange selectivity of phenol-type sorbents based on phenol formaldehyde resins, products of condensation of diatomic phenols with formaldehyde, and crosslinked polymer based on C-phenyl[4]resorcinarene resin, for cesium and rubidium ions. It is shown that phenol formaldehyde sorbents are the ones most selective. The interaction of alkali metal cations with the anion of calix[4]arene is investigated via quantum-chemical modeling. It is shown that the selectivity toward cesium and rubidium ions in ion exchangers of the phenolic type is not due to specific interactions of ions with phenolic groups.

  18. Modified BET Equation for Determination of Micropore Pore Volume and Mesopore Surface Area in Microporous-Mesoporous Solids.

    Czech Academy of Sciences Publication Activity Database

    Šolcová, Olga; Mat?jová, Lenka; Hudec, P.; Schneider, Petr

    Cambridge : RSC Publishing, 2009, s. 218-224 ISBN 978-1-84755-904-3 R&D Projects: GA AV ?R IAA4072404; GA AV ?R KAN400720701 Institutional research plan: CEZ:AV0Z40720504 Keywords : microporous-mesoporous solids * mesopore surface area Subject RIV: CF - Physical ; Theoretical Chemistry

  19. 21 CFR 172.280 - Terpene resin.

    Science.gov (United States)

    2010-04-01

    ... 3 2010-04-01 2009-04-01 true Terpene resin. 172.280 Section 172.280 Food...Films and Related Substances § 172.280 Terpene resin. The food additive terpene resin may be safely used in accordance...

  20. Method of removing contaminants from plastic resins

    Science.gov (United States)

    Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

    2008-11-18

    A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

  1. Method for removing contaminants from plastic resin

    Science.gov (United States)

    Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

    2008-12-30

    A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

  2. Synthesis of improved phenolic resins

    Science.gov (United States)

    Delano, C. B.; Mcleod, A. H.

    1979-01-01

    Twenty seven addition cured phenolic resin compositions were prepared and tested for their ability to give char residues comparable to state-of-the-art phenolic resins. Cyanate, epoxy, allyl, acrylate, methacrylate and ethynyl derivatized phenolic oligomers were investigated. The novolac-cyanate and propargyl-novolac resins provided anaerobic char yields at 800 C of 58 percent. A 59 percent char yield was obtained from modified epoxy novolacs. A phosphonitrilic derivative was found to be effective as an additive for increasing char yields. The novolac-cyanate, epoxy-novolac and methacrylate-epoxy-novolac systems were investigated as composite matrices with Thornel 300 graphite fiber. All three resins showed good potential as composite matrices. The free radical cured methacrylate-epoxy-novolac graphite composite provided short beam shear strengths at room temperature of 93.3 MPa (13.5 ksi). The novolac-cyanate graphite composite produced a short beam shear strength of 74 MPa (10.7 ksi) and flexural strength of 1302 MPa (189 ksi) at 177 C. Air heat aging of the novolac-cyanate and epoxy novolac based composites for 12 weeks at 204 C showed good property retention.

  3. Radiation crosslinked vinyl chloride resin

    International Nuclear Information System (INIS)

    A blended composition comprising a vinyl chloride resin and a specific epoxy compound derived from a conjugated diene homopolymer and/or copolymer can advantageously be crosslinked by means of an ionizing radiation. Said epoxy compound is bonded with an ethylenically unsaturated organic acid having a double bond adjacent the carboxyl group to a part of the epoxy group of the epoxy compound

  4. Resins production: batch plant automation

    International Nuclear Information System (INIS)

    Companies that look for automation in their plants without external resources, have at their disposal flexible, custom and easy to use DCS, open towards PLC. In this article it is explained why Hoechts has followed this way of new plants for resins production automation

  5. Fluorescence properties of dye doped mesoporous silica

    Energy Technology Data Exchange (ETDEWEB)

    Carbonaro, Carlo M., E-mail: cm.carbonaro@dsf.unica.it; Corpino, Riccardo, E-mail: cm.carbonaro@dsf.unica.it; Ricci, Pier Carlo, E-mail: cm.carbonaro@dsf.unica.it; Chiriu, Daniele, E-mail: cm.carbonaro@dsf.unica.it [Department of Physics, University of Cagliari, Campus of Monserrato, s.p. no 8, km 0.700, 09042 Monserrato (Italy); Cannas, Carla [Department of Chemical and Geological Sciences, University of Cagliari, Campus of Monserrato, s.p. no 8, km 0.700, 09042 Monserrato (Italy)

    2014-10-21

    In this paper we present a review of the main results we obtained studying the emission properties of organic-inorganic hybrids obtained combining mesoporous silica and Xantene dyes, in particular the standard reference Rhodamine 6G. The purpose of the review is to show the possibility to efficiently 'dope' the transparent inorganic porous matrix to obtain promising systems for photonic and biomedical applications. The strategies to solve the concentration effect and the leaching phenomenon are discussed within the framework of the single exciton theory.

  6. Functionalized bimodal mesoporous silicas as carriers for controlled aspirin delivery

    International Nuclear Information System (INIS)

    The bimodal mesoporous silica modified with 3-aminopropyltriethoxysilane was performed as the aspirin carrier. The samples' structure, drug loading and release profiles were characterized with X-ray diffraction, scanning electron microscopy, N2 adsorption and desorption, Fourier transform infrared spectroscopy, TG analysis, elemental analysis and UV-spectrophotometer. For further exploring the effects of the bimodal mesopores on the drug delivery behavior, the unimodal mesoporous material MCM-41 was also modified as the aspirin carrier. Meantime, Korsmeyer-Peppas equation ft=ktn was employed to analyze the dissolution data in details. It is indicated that the bimodal mesopores are beneficial for unrestricted drug molecules diffusing and therefore lead to a higher loading and faster releasing than that of MCM-41. The results show that the aspirin delivery properties are influenced considerably by the mesoporous matrix, whereas the large pore of bimodal mesoporous silica is the key point for the improved controlled-release properties. - Graphical abstract: Loading (A) and release profiles (B) of aspirin in N-BMMs and N-MCM-41 indicated that BMMs have more drug loading capacity and faster release rate than that MCM-41. Highlights: ? Bimodal mesoporous silicas (BMMs) and MCM-41 modified with amino group via post-treatment procedure. ? Loading and release profiles of aspirin in modified BMMs and MCM-41. ? Modified BMMs have more drug loading capacity and faster release rate than that modified MCM-41.

  7. Recovery of platinum, tin and indium from spent catalysts in chloride medium using strong basic anion exchange resins

    Energy Technology Data Exchange (ETDEWEB)

    Marinho, Roberta Santos; Silva, Cristiano Nunes da [Analytical Chemistry Department, Institute of Chemistry, Federal University of Rio de Janeiro, Av. Athos da Silveira Ramos, 149, room A509, 21941-909, Ilha do Fundao, Rio de Janeiro (Brazil); Afonso, Julio Carlos, E-mail: julio@iq.ufrj.br [Analytical Chemistry Department, Institute of Chemistry, Federal University of Rio de Janeiro, Av. Athos da Silveira Ramos, 149, room A509, 21941-909, Ilha do Fundao, Rio de Janeiro (Brazil); Cunha, Jose Waldemar Silva Dias da [Department of Chemistry and Nuclear Materials, Institute of Nuclear Engineering, Rua Helio de Almeida, 75, 21941-906, Ilha do Fundao, Rio de Janeiro, Ramos Brazil (Brazil)

    2011-09-15

    Highlights: {yields} Platinum, tin and indium recoveries from spent reforming catalysts. {yields} Adsorption of metal chlorocomplexes on strongly basic anion-exchange resins. {yields} Sequential desorption via elution with reducing (Pt, Sn) or complexing (In) agents. {yields} The elements were recovered in very high yields. {yields} The anion-exchange resins can be reused. - Abstract: This work describes a route for platinum recovery from spent commercial Pt and PtSnIn/Al{sub 2}O{sub 3} catalysts using strong basic mesoporous and macroporous anion exchange resins (Cl{sup -} form). The catalysts were leached with aqua regia (75 {sup o}C, 20-25 min). Platinum adsorption was influenced by the presence of other metals which form chlorocomplexes (tin, indium) and also base metals (aluminum). However, it was possible to overcome this fact by a sequential desorption procedure. Aluminum was selectively removed from the resins by elution with 3 mol L{sup -1} HCl. Platinum was desorbed passing 1 mol L{sup -1} Na{sub 2}S{sub 2}O{sub 3} (pH 9). Tin was removed by elution with 0.1 mol L{sup -1} ascorbic acid. Indium was removed using 0.1 mol L{sup -1} EDTA as eluent. Desorption efficiency exceeded 99% for all metals. Metals were recovered in high yields (>98 wt%).

  8. Recovery of platinum, tin and indium from spent catalysts in chloride medium using strong basic anion exchange resins

    International Nuclear Information System (INIS)

    Highlights: ? Platinum, tin and indium recoveries from spent reforming catalysts. ? Adsorption of metal chlorocomplexes on strongly basic anion-exchange resins. ? Sequential desorption via elution with reducing (Pt, Sn) or complexing (In) agents. ? The elements were recovered in very high yields. ? The anion-exchange resins can be reused. - Abstract: This work describes a route for platinum recovery from spent commercial Pt and PtSnIn/Al2O3 catalysts using strong basic mesoporous and macroporous anion exchange resins (Cl- form). The catalysts were leached with aqua regia (75 oC, 20-25 min). Platinum adsorption was influenced by the presence of other metals which form chlorocomplexes (tin, indium) and also base metals (aluminum). However, it was possible to overcome this fact by a sequential desorption procedure. Aluminum was selectively removed from the resins by elution with 3 mol L-1 HCl. Platinum was desorbed passing 1 mol L-1 Na2S2O3 (pH 9). Tin was removed by elution with 0.1 mol L-1 ascorbic acid. Indium was removed using 0.1 mol L-1 EDTA as eluent. Desorption efficiency exceeded 99% for all metals. Metals were recovered in high yields (>98 wt%).

  9. Silylation and metalation of periodic mesoporous silica

    Energy Technology Data Exchange (ETDEWEB)

    Deschner, Thomas Christian

    2011-07-01

    Surface functionalization via silylation or SOMC (Surface Organometallic Chemistry) is a prosperous field for producing organic-inorganic hybrid materials. These concepts are proven by numerous applications in various topical areas like catalysis, chromatography, adsorption processes, as well as gas sensing and storage. The combination of a thermally stable high surface area inorganic host and a reactive surface chemistry which allows the control of dispersion of the surface species and fine tuning of the properties of the subsequent hybrid material is an endeavour especially in heterogeneous catalysis. The subgroup of cage-like PMS (Periodic Mesoporous Silica) materials comprising of SBA-1, SBA-2, SBA-6, SBA-I6 or KIT-5 are currently attractive candidates for designing size and shape selective catalysts. (Silyl)amides enjoy great popularity in (surface) organometallic chemistry because most of the metals of the periodic table form stable complexes with these ligands. Chapter A gives a brief summary of microporous and mesoporous materials in general and introduces compendiously possible surface modifications with special emphasis on silylation. In addition an overview of metal (silyl)amides[et]porous and metal (silyl)amides[et]nonporous support is presented. Chapter C deals with the summary of the main results placing emphasis on: distinct reactivity of various silylation reagents; distinct reactivity of metal (silyl)amides of the elements Mg, Ti, and Fe; o occurrence of any size effects; feasibility of consecutive intrapore chemistry. (Author)

  10. Smart Mesoporous Nanomaterials for Antitumor Therapy

    Directory of Open Access Journals (Sweden)

    Marina Martínez-Carmona

    2015-11-01

    Full Text Available The use of nanomaterials for the treatment of solid tumours is receiving increasing attention by the scientific community. Among them, mesoporous silica nanoparticles (MSNs exhibit unique features that make them suitable nanocarriers to host, transport and protect drug molecules until the target is reached. It is possible to incorporate different targeting ligands to the outermost surface of MSNs to selectively drive the drugs to the tumour tissues. To prevent the premature release of the cargo entrapped in the mesopores, it is feasible to cap the pore entrances using stimuli-responsive nanogates. Therefore, upon exposure to internal (pH, enzymes, glutathione, etc. or external (temperature, light, magnetic field, etc. stimuli, the pore opening takes place and the release of the entrapped cargo occurs. These smart MSNs are capable of selectively reaching and accumulating at the target tissue and releasing the entrapped drug in a specific and controlled fashion, constituting a promising alternative to conventional chemotherapy, which is typically associated with undesired side effects. In this review, we overview the recent advances reported by the scientific community in developing MSNs for antitumor therapy. We highlight the possibility to design multifunctional nanosystems using different therapeutic approaches aimed at increasing the efficacy of the antitumor treatment.

  11. Continuous microwave flow synthesis of mesoporous hydroxyapatite.

    Science.gov (United States)

    Akram, Muhammad; Alshemary, Ammar Z; Goh, Yi-Fan; Wan Ibrahim, Wan Aini; Lintang, Hendrik O; Hussain, Rafaqat

    2015-11-01

    We have successfully used continuous microwave flow synthesis (CMFS) technique for the template free synthesis of mesoporous hydroxyapatite. The continuous microwave flow reactor consisted of a modified 2.45GHz household microwave, peristaltic pumps and a Teflon coil. This cost effective and efficient system was exploited to produce semi-crystalline phase pure nano-sized hydroxyapatite. Effect of microwave power, retention time and the concentration of reactants on the phase purity, degree of crystallinity and surface area of the final product was studied in detail. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to study the phase purity and composition of the product, while transmission electron microscopy (TEM) was used to study the effect of process parameters on the morphology of hydroxyapatite. The TEM analysis confirmed the formation of spherical particles at low microwave power; however the morphology of the particles changed to mesoporous needle and rod-like structure upon exposing the reaction mixture to higher microwave power and longer retention time inside the microwave. The in-vitro ion dissolution behavior of the as synthesized hydroxyapatite was studied by determining the amount of Ca(2+) ion released in SBF solution. PMID:26249601

  12. Core/shell magnetic mesoporous silica nanoparticles with radially oriented wide mesopores

    OpenAIRE

    Nikola Ž. Kneževi?

    2014-01-01

    Core/shell nanoparticles, containing magnetic iron-oxide (maghemite) core and mesoporous shell with radial porous structure, were prepared by dispersing magnetite nanoparticles and adding tetraethylorthosilicate to a basic aqueous solution containing structure-templating cetyltrimethylammonium bromide and a pore-swelling mesithylene. The material is characterized by SEM and TEM imaging, nitrogen sorption and powder X-ray di?raction. Distinctive features of the prepared material are its high s...

  13. Thermally stable crystalline mesoporous metal oxides with substantially uniform pores

    Energy Technology Data Exchange (ETDEWEB)

    Wiesner, Ulrich; Orilall, Mahendra Christopher; Lee, Jinwoo; DiSalvo, Jr., Francis J

    2015-01-27

    Highly crystalline metal oxide-carbon composites, as precursors to thermally stable mesoporous metal oxides, are coated with a layer of amorphous carbon. Using a `one-pot` method, highly crystalline metal oxide-carbon composites are converted to thermally stable mesoporous metal oxides, having highly crystalline mesopore walls, without causing the concomitant collapse of the mesostructure. The `one-pot` method uses block copolymers with an sp or sp 2 hybridized carbon containing hydrophobic block as structure directing agents which converts to a sturdy, amorphous carbon material under appropriate heating conditions, providing an in-situ rigid support which maintains the pores of the oxides intact while crystallizing at temperatures as high as 1000 deg C. A highly crystalline metal oxide-carbon composite can be heated to produce a thermally stable mesoporous metal oxide consisting of a single polymorph.

  14. Synthesis of mesoporous nano-hydroxyapatite by using zwitterions surfactant

    Science.gov (United States)

    Mesoporous nano-hydroxyapatite (mn-HAP) was successfully synthesized via a novel micelle-templating method using lauryl dimethylaminoacetic acid as zwitterionic surfactant. The systematic use of such a surfactant in combination with microwave energy inputenables the precise contr...

  15. Radiation effect of epoxy resin by electron beams

    International Nuclear Information System (INIS)

    The study was aimed at understanding behaviors of epoxy resins under electron beam irradiation, Epoxy resins of different molecular structures, which include glycidyl ether resin, glycidyl ester resin, glycidyl amine resin, and alicyclic epoxy resin, were irradiated with 5 MeV electron beams. The irradiated samples were investigated with their viscosity changes, weight losses and gaseous molecules generated by the irradiation. The results show that the glycidyl ester resin and the epoxy containing ester group underwent the most serious decomposition by the irradiation, while the glycidyl amine resin was decomposed less seriously and the glycidyl ether resin was the least decomposed. (authors)

  16. Mesoporous zeolite single crystals for catalytic hydrocarbon conversion

    DEFF Research Database (Denmark)

    Schmidt, I.; Christensen, C.H.; Hasselriis, Peter; Kustova, Marina; Nielsen, Michael Brorson; Dahl, Søren; Johannsen, K.; Christensen, Claus H.

    2005-01-01

    Recently, mesoporous zeolite single crystals were discovered. They constitute a novel family of materials that features a combined micropore and mesopore architecture within each individual crystal. Here, we briefly summarize recent catalytic results from cracking and isomerization of alkalies, alkylation of aromatics and present new results on isomerization of aromatics. Specifically, the shape-selective isomerization of meta-xylenc into para-xylene and ortho-xylene is studied. In all these rea...

  17. Low temperature crystallisation of mesoporous TiO2

    OpenAIRE

    Peter Kohn; Sandeep Pathak; Morgan Stefik; Caterina Ducati; Ulrich Wiesner; Ullrich Steiner; Stefan Guldin

    2013-01-01

    Conducting mesoporous TiO2 is rapidly gaining importance for green energy applications. To optimise performance, its porosity and crystallinity must be carefully fine-tuned. To this end, we have performed a detailed study on the temperature dependence of TiO2 crystallisation in mesoporous films. Crystal nucleation and growth of initially amorphous TiO2 derived by hydrolytic sol-gel chemistry is compared to the evolution of crystallinity from nanocrystalline building blocks obtained from non-h...

  18. Near-infrared emission from mesoporous crystalline germanium

    Energy Technology Data Exchange (ETDEWEB)

    Boucherif, Abderraouf; Aimez, Vincent; Arès, Richard, E-mail: richard.ares@usherbrooke.ca [Institut Interdisciplinaire d’Innovation Technologique (3IT), Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, J1K OA5, Québec (Canada); Laboratoire Nanotechnologies Nanosystèmes (LN2)-CNRS UMI-3463, Université de Sherbrooke, 3000 Boulevard Université, Sherbrooke, J1K OA5, Québec (Canada); Korinek, Andreas [Canadian Centre for Electron Microscopy, Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario, L8S 4M1 (Canada)

    2014-10-15

    Mesoporous crystalline germanium was fabricated by bipolar electrochemical etching of Ge wafer in HF-based electrolyte. It yields uniform mesoporous germanium layers composed of high density of crystallites with an average size 5-7 nm. Subsequent extended chemical etching allows tuning of crystallites size while preserving the same chemical composition. This highly controllable nanostructure exhibits photoluminescence emission above the bulk Ge bandgap, in the near-infrared range (1095-1360nm) with strong evidence of quantum confinement within the crystallites.

  19. Mesoporous carbons as low temperature fuel cell platinum catalyst supports

    OpenAIRE

    GHIOTTI, Giovanna; MANZOLI, Maela

    2008-01-01

    Platinum catalysts supported on ordered mesoporous carbons (OMC) are described. The mesoporous carbon support, CMK3 type, was synthesised as an inverse replica of a SBA-15 silica template. The platinum catalysts (i.e. Pt 20 wt% and Pt 10 wt%, respectively), obtained through a conventional wet impregnation method, have been investigated to determine their structural characteristics and electrochemical behaviour. The electro-catalytic performance towards the oxygen reduc...

  20. Electrochemical Hydrogen Storage in a Highly Ordered Mesoporous Carbon

    OpenAIRE

    LIU, DAN; Zeng, Chao; Tang, Haolin; Zheng, Dong; Li, Rong; Qu, Deyu; Xie, Zhizhong; Lei, Jiahen; Xiao, Liang; Qu, Deyang

    2014-01-01

    A highly ordered mesoporous carbon (HOMC) has been synthesized through a strongly acidic, aqueous cooperative assembly route. The structure and morphology of the carbon material were investigated using TEM, SEM, and nitrogen adsorption–desorption isotherms. The carbon was proven to be meso-structural and consisted of graphitic micro-domain with larger interlayer space. Active carbon impedance and electrochemical measurements reveal that the synthesized highly ordered mesoporous carbon (HOMC) ...

  1. Novel Syntheses, Structures and Functions of Mesoporous Silica Materials

    OpenAIRE

    Atluri, Rambabu

    2010-01-01

    The field of mesoporous silica has been studied for about 20 years but it is still an area attracting a lot of attention. The use of novel templating molecules and several issues related to the synthesis and fine structural details are still poorly understood. These aspects are of special relevance to the theme of this thesis, which includes novel work on three fronts; the synthesis, characterization and applications of mesoporous materials. The work described in this thesis aims to contribut...

  2. Perspectives of micro/mesoporous composites in catalysis.

    Czech Academy of Sciences Publication Activity Database

    ?ejka, Ji?í; Mintova, S.

    2007-01-01

    Ro?. 49, ?. 4 (2007), s. 457-509. ISSN 0161-4940 R&D Projects: GA ?R GA203/05/0197; GA ?R GA104/05/0192; GA AV ?R 1QS400400560; GA AV ?R 1ET400400413 Institutional research plan: CEZ:AV0Z40400503 Keywords : micro/mesoporous composite * zeolites * mesoporous molecular sieves * synthesis Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 6.333, year: 2007

  3. Recent Advances in Catalysis Over Mesoporous Molecular Sieves.

    Czech Academy of Sciences Publication Activity Database

    Martín-Aranda, R. M.; ?ejka, Ji?í

    2010-01-01

    Ro?. 53, 3-4 (2010), s. 141-153. ISSN 1022-5528 R&D Projects: GA AV ?R KAN100400701; GA AV ?R IAA400400805; GA ?R GA104/09/0561 Institutional research plan: CEZ:AV0Z40400503 Keywords : mesoporous molecular sieves * MCM-41 * SBA-15 * mesoporous alumina Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.359, year: 2010

  4. Reinforcement of Denture Base Resins

    OpenAIRE

    T Nejatiant; J Van Noortr

    2005-01-01

    Introduction: PMMA has been the most popular denture base material because of its advantages including good aesthetics, accurate fit, stability in the oral environment, easy laboratory and clinical manipulation and inexpensive equipments since the 1930’s. However, its fracture resistance is not satisfactory. Aim: The aim of this study is to improve the fracture resistance of denture bases made of PMMA by assessing the effect of resin type, packing and processing variables on biaxial flexural ...

  5. 21 CFR 175.300 - Resinous and polymeric coatings.

    Science.gov (United States)

    2010-04-01

    ...) Natural fossil resins, as the basic resin: Copal. Damar. Elemi. Gilsonite. Glycerol ester of damar, copal, elemi, and sandarac. Sandarac. Shellac. Utah coal resin. (v) Rosins and rosin derivatives, with or... (limed rosin). Zinc resinate. (vi) Phenolic resins as the basic polymer formed by reaction of...

  6. Ultrasound-driven design of new mesoporous metal catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Schaeferhans, Jana; Pazos Perez, Nicolas; Andreeva, Daria [Physikalische Chemie II, Univ. Bayreuth (Germany); Skorb, Ekaterina [Max-Planck-Institut fuer Kolloid- und Grenzflaechenforschung, Golm (Germany)

    2011-07-01

    Mesoporous metal nanocomposites were formed by a ''green chemistry'' method with ultrasound irradiation. The sonication technique combines the fabrication of a mesoporous support consisting of metallic particles (Al, Mg) several tens of micrometers in size and the subsequent incorporation of metal (Ag, Au, Pt etc.) nanoparticles into its pores. Next to filling the mesoporous support with particles we are also able to form mesoporous alloys e.g. AlNi or CoAlFe. The resulting material is analyzed by transmission electron microscopy, powder X-ray diffraction, small-angle neutron scattering and the Brunauer-Emmett-Teller and the Barrett-Joyner-Halenda method. Surface areas up to 200 m{sup 2}/g with a narrow pore size distribution around 3 nm can be achieved. The mesoporous structures are analyzed by confocal light microscopy after coloring the particles with dye. We explain the formation of the mesoporous inner structures by the following mechanism: Thermal etching and recrystallization of metals by ultrasound-stimulated high-speed jets of liquid form the porous structure that is stabilized by surface oxidation through free radicals generated during cavitation. We expect this approach to be universal and opening perspectives for a whole new class of catalytic materials that can be prepared in a fairly easy and cost effective way.

  7. Progress on the Multifunctional Mesoporous Silica-based Nanotheranostics

    Directory of Open Access Journals (Sweden)

    SHI Jian-Lin, CHEN Yu, CHEN Hang-Rong

    2013-01-01

    Full Text Available Inorganic mesoporous nano-biomaterials have broad application potentials in molecular imaging, targeted drug delivery, tissue engineering, gene therapy, and non-invasive surgical therapy, etc., which are of great significance in the early diagnosis and efficient therapy of serious diseases such as cancer. This article reviews the most recent research advances and outlooks future development trends of mesoporous nanotheranostics based on clinical requirements, the principle of nano-synthetic chemistry and the design strategy of multifunctional mesoporous nano-biomaterials, by combining the recent achievements of our group. By integrating various functions into mesoporous silica nanoparticles to endow them with special capabilities, the mesoporous nanotheranostics could act as the contrast agents for clinical molecular imaging (magnetic resonance imaging, fluorescent imaging and the combinations of various imaging modalities, as well as the carriers for the encapsulation and delivery of drugs for the therapy of diseases (chemotherapy, gene therapy, photodynamic therapy and non-invasive surgical therapy. With the development of bio-nanotechnology and nano-synthetic chemistry, mesoporous nanotheranostics are expected to satisfy the clinical requirements following the systematic investigation of their biological effects and bio-safety, and finally find their applications in clinical practices to benefit human beings.

  8. Reinforcement of Denture Base Resins

    Directory of Open Access Journals (Sweden)

    T Nejatiant

    2005-10-01

    Full Text Available Introduction: PMMA has been the most popular denture base material because of its advantages including good aesthetics, accurate fit, stability in the oral environment, easy laboratory and clinical manipulation and inexpensive equipments since the 1930’s. However, its fracture resistance is not satisfactory. Aim: The aim of this study is to improve the fracture resistance of denture bases made of PMMA by assessing the effect of resin type, packing and processing variables on biaxial flexural strength (BFS. Materials & methods: 930 discs, 12 mm diameter and 2 mm thick were prepared with the following variables: a. Veined (V and Plain (P PMMA. b. 5 different powder/liquid ratios by volume (1.5:1, 2:1, 2.5:1, 3:1, 3.5:1. c. Conventional (C and Injection packing methods (I. d. Dry heat (D Water bath (W; and e. different curing times. The discs were trimmed and stored in 37°C tap water for 50 hours before carrying out BFS test, according to BS EN ISO 1567: 2001. BFS test was carried out using a tensile-testing machine (Lloyd LRX, Lloyd instruments Ltd (Figure.1 b, with a x-head speed of 1mm/min. ONE-WAY ANOVA analysis and TUKEY’S comparison were carried out (MINITAB. The temperature within the curing baths and inside of curing resin was evaluated by using a thermocouple. Results: BFS of Powder/liquid ratio of 1.5:1 is significantly lower than the other four ratios. Among the last four ratios, 2.5:1 was the strongest one although the difference was not significant. BFS of the plain type of PMMA is significantly higher than the veined type.• BFS of conventionally packed PMMA discs was greater than the injectional packed ones and the difference is significant. Water bath cured resin showed a significant higher BFS compared with dry heat curing. • Changing the curing time in the dry heat bath from 7h @ 75º C and 2hrs @ 95º C to 5hrs @ 75º C and 3hrs @ 95º C and then 2hrs @ 95º C improves BFS of PMMA. In the water bath the trend is identical although the difference is not significant. Analysis of the temperature climb and hold within the curing bathes showed a consistent performance with the water bath irrespective the number of the flasks being cured. Meanwhile, the dry heat bath showed very inconsistent results. Conclusion: 1. Type of resin, packing procedure and processing variables can have major effect on BFS of PMMA. 2. Using plain resin, conventional packing, water bath curing with two hours at 95 ºC are recommended conditions.

  9. Modified BET Equation for Determination of Micropore Pore Volume and Mesopore Surface Area in Microporous-Mesoporous Solids.

    Czech Academy of Sciences Publication Activity Database

    Šolcová, Olga; Mat?jová, Lenka; Hudec, P.; Schneider, Petr

    Edinburgh : University of Edinburgh, 2008, s. 103. ISBN N. [8th International Symposium on the Characterisation of Porous Solids. Edinburgh (GB), 10.06.2008-13.06.2008] R&D Projects: GA AV ?R IAA4072404; GA AV ?R KAN400720701 Institutional research plan: CEZ:AV0Z40720504 Keywords : microporous-mesoporous solids * mesopore surface area Subject RIV: CF - Physical ; Theoretical Chemistry

  10. Porous Ceramic Spheres from Ion Exchange Resin

    Science.gov (United States)

    Dynys, Fred

    2005-01-01

    A commercial cation ion exchange resin, cross-linked polystyrene, has been successfully used as a template to fabricate 20 to 50 micron porous ceramic spheres. Ion exchange resins have dual template capabilities. Pore architecture of the ceramic spheres can be altered by changing the template pattern. Templating can be achieved by utilizing the internal porous structure or the external surface of the resin beads. Synthesis methods and chemical/physical characteristics of the ceramic spheres will be reported.

  11. Bond strength of resin-resin interfaces contaminated with saliva and submitted to different surface treatments

    DEFF Research Database (Denmark)

    Furuse, Adilson Yoshio; da Cunha, Leonardo Fernandes; Benetti, Ana Raquel; Mondelli, José

    2007-01-01

    The purpose of this study was to investigate the effect of different surface treatments on shear bond strength of saliva-contaminated resin-resin interfaces. Flat resin surfaces were fabricated. In the control group, no contamination or surface treatment was performed. The resin surfaces of the experimental groups were contaminated with saliva and air-dried, and then submitted to: (G1) rinsing with water and drying; (G2) application of an adhesive system; (G3) rinsing and drying, abrasion with f...

  12. Synthesis of ordered mesoporous U{sub 3}O{sub 8} by a nanocasting route

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Ran; Wang, Lin; Gu, Zhan-Jun; Yuan, Li-Yong; Xiao, Cheng-Liang; Zhao, Yu-Liang; Shi, Wei-Qun [Institute of High Energy Physics, Beijing (China). Key Laboratory of Nuclear Radiation and Nuclear Energy Technology; Chai, Zhi-Fang [Institute of High Energy Physics, Beijing (China). Key Laboratory of Nuclear Radiation and Nuclear Energy Technology; Soochow Univ., Suzhou (China). School of Radiological and Interdisciplinary Sciences

    2014-11-01

    Ordered mesoporous U{sub 3}O{sub 8} has been synthesized by a nanocasting route using mesoporous silica (KIT-6 and SBA-15) as templates and characterized by using XRD, SEM and nitrogen adsorption/desorption techniques.

  13. The absorption of plutonium by anion resins

    International Nuclear Information System (INIS)

    Equilibrium experiments have shown Pu+4 to be absorbed from nitric acid onto an anion resin as a complex anion Pu(NO3)6-2. The amount of absorption is dependent on the plutonium and nitric acid concentrations in the equilibrium solution with a maximum at 7N to 8N HNO3. A low cross-linked resin has a higher capacity and reaches equilibrium more rapidly than the normally supplied resin. Saturation capacity of one per cent cross-linked Nalcite SBR (Dowex 1), 50 -- 100 mesh, is 385 mg Pu/gram dry resin. (author)

  14. Flexible heat resistant neutron shielding resin

    Energy Technology Data Exchange (ETDEWEB)

    Sukegawa, Atsuhiko M., E-mail: morioka.atsuhiko@jaea.go.jp [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka-machi, Ibaraki 311-0193 (Japan); Anayama, Yoshimasa [Neo-Tech R and D, 6-6-1, Ginza, Chuo-ku, Tokyo 104-0061 (Japan); Okuno, Koichi, E-mail: okunok@hazama.co.jp [Hazama Technical Research Institute, 515-1 Karima, Tsukuba-shi, Ibaraki 305-0822 (Japan); Sakurai, Shinji, E-mail: sakurai.shinji@jaea.go.jp [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka-machi, Ibaraki 311-0193 (Japan); Kaminaga, Atsushi, E-mail: kaminaga.atsushi@jaea.go.jp [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka-machi, Ibaraki 311-0193 (Japan)

    2011-10-01

    A flexible heat resistant neutron shielding material has been developed, which consists of polymer resin with 1 wt% boron. The neutron shielding performance of the developed resin, examined by the {sup 252}Cf neutron source, is almost the same as that of the polyethylene. The outgas of H{sub 2}, H{sub 2}O, CO and CO{sub 2} from the resin have been measured at {approx}250 deg. C environment. The resin will be applied around the port of the vacuum vessel as an additional shielding material and reduce the neutron streaming from a superconducting tokamak device such as JT-60SA.

  15. Flexible heat resistant neutron shielding resin

    Science.gov (United States)

    Sukegawa, Atsuhiko M.; Anayama, Yoshimasa; Okuno, Koichi; Sakurai, Shinji; Kaminaga, Atsushi

    2011-10-01

    A flexible heat resistant neutron shielding material has been developed, which consists of polymer resin with 1 wt% boron. The neutron shielding performance of the developed resin, examined by the 252Cf neutron source, is almost the same as that of the polyethylene. The outgas of H 2, H 2O, CO and CO 2 from the resin have been measured at ˜250 °C environment. The resin will be applied around the port of the vacuum vessel as an additional shielding material and reduce the neutron streaming from a superconducting tokamak device such as JT-60SA.

  16. Flexible heat resistant neutron shielding resin

    International Nuclear Information System (INIS)

    A flexible heat resistant neutron shielding material has been developed, which consists of polymer resin with 1 wt% boron. The neutron shielding performance of the developed resin, examined by the 252Cf neutron source, is almost the same as that of the polyethylene. The outgas of H2, H2O, CO and CO2 from the resin have been measured at ?250 deg. C environment. The resin will be applied around the port of the vacuum vessel as an additional shielding material and reduce the neutron streaming from a superconducting tokamak device such as JT-60SA.

  17. Novel silica-based ion exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-01

    Eichrom`s highly successful Diphonixo resin resembles a conventional ion exchange resin in its use of sulfonic acid ligands on a styrene- divinylbenzene matrix. Diphonix resin exhibits rapid exchange kinetics that allow economical operation of ion exchange systems. Unlike conventional resins, Diphonix resin contains chelating ligands that are diphosphonic acid groups that recognize and remove the targeted metals and reject the more common elements such as sodium, calcium and magnesium. This latter property makes Diphonix ideal for many industrial scale applications, including those involving waste treatment. For treatment of low-level, transuranic (TRU) and high- level radioactive wastes, Diphonix`s polystyrene backbone hinders its application due to radiolytic stability of the carbon-hydrogen bonds and lack of compatibility with expected vitrification schemes. Polystyrene-based Diphonix is approximately 60% carbon- hydrogen. In response to an identified need within the Department of Energy for a resin with the positive attributes of Diphonix that also exhibits greater radiolytic stability and final waste form compatibility, Eichrom has successfully developed a new, silica-based resin version of Diphonix. Target application for this new resin is for use in environmental restoration and waste management situations involving the processing of low-level, transuranic and high-level radioactive wastes. The resin can also be used for processing liquid mixed waste (waste that contains low level radioactivity and hazardous constituents) including mixed wastes contaminated with organic compounds. Silica-based Diphonix is only 10% carbon-hydrogen, with the bulk of the matrix silica.

  18. Gyroidal mesoporous multifunctional nanocomposites via atomic layer deposition

    Science.gov (United States)

    Werner, Jörg G.; Scherer, Maik R. J.; Steiner, Ullrich; Wiesner, Ulrich

    2014-07-01

    We demonstrate the preparation of rationally designed, multifunctional, monolithic and periodically ordered mesoporous core-shell nanocomposites with tunable structural characteristics. Three-dimensionally (3D) co-continuous gyroidal mesoporous polymer monoliths are fabricated from a solution-based triblock terpolymer-resol co-assembly and used as the functional templates for the fabrication of free-standing core-shell carbon-titania composites using atomic layer deposition (ALD). The deposition depth into the torturous gyroidal nanonetwork is investigated as a function of ALD conditions and the resulting composites are submitted to different thermal treatments. Results suggest that ALD can homogenously coat mesoporous templates with well defined pore sizes below 50 nm and thicknesses above 10 ?m. Structural tunability like titania shell thickness and pore size control is demonstrated. The ordered nanocomposites exhibit triple functionality; a 3D continuous conductive carbon core that is coated with a crystalline titania shell that in turn is in contact with a 3D continuous mesopore network in a compact monolithic architecture. This materials design is of interest for applications including energy conversion and storage. Gyroidal mesoporous titania monoliths can be obtained through simultaneous titania crystallization and template removal in air.We demonstrate the preparation of rationally designed, multifunctional, monolithic and periodically ordered mesoporous core-shell nanocomposites with tunable structural characteristics. Three-dimensionally (3D) co-continuous gyroidal mesoporous polymer monoliths are fabricated from a solution-based triblock terpolymer-resol co-assembly and used as the functional templates for the fabrication of free-standing core-shell carbon-titania composites using atomic layer deposition (ALD). The deposition depth into the torturous gyroidal nanonetwork is investigated as a function of ALD conditions and the resulting composites are submitted to different thermal treatments. Results suggest that ALD can homogenously coat mesoporous templates with well defined pore sizes below 50 nm and thicknesses above 10 ?m. Structural tunability like titania shell thickness and pore size control is demonstrated. The ordered nanocomposites exhibit triple functionality; a 3D continuous conductive carbon core that is coated with a crystalline titania shell that in turn is in contact with a 3D continuous mesopore network in a compact monolithic architecture. This materials design is of interest for applications including energy conversion and storage. Gyroidal mesoporous titania monoliths can be obtained through simultaneous titania crystallization and template removal in air. Electronic supplementary information (ESI) available: Photographs of flexible templates and the Beneq ALD reactor indicating the different sample positioning. See DOI: 10.1039/c4nr01948b

  19. 75 FR 67105 - Granular Polytetrafluoroethylene Resin From Italy and Japan

    Science.gov (United States)

    2010-11-01

    ...Polytetrafluoroethylene Resin From Italy and Japan AGENCY: United States International Trade...polytetrafluoroethylene resin from Italy and Japan...polytetrafluoroethylene resin from Italy and Japan would be likely to lead to...

  20. 40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

    Science.gov (United States)

    2010-07-01

    ...2010-07-01 2010-07-01 false Epoxy resin containing phosphorus (generic...Specific Chemical Substances § 721.2752 Epoxy resin containing phosphorus (generic...chemical substance identified generically as an epoxy resin containing phosphorus (PMN...

  1. 40 CFR 721.2755 - Cycloaliphatic epoxy resin (generic).

    Science.gov (United States)

    2010-07-01

    ...2010-07-01 false Cycloaliphatic epoxy resin (generic). 721.2755 Section...Substances § 721.2755 Cycloaliphatic epoxy resin (generic). (a) Chemical substance...identified generically as cycloaliphatic epoxy resin (PMN P-98-105) is...

  2. 40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

    Science.gov (United States)

    2010-07-01

    ...2010-07-01 2010-07-01 false Aromatic aldehyde phenolic resin (generic). 721...Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a...substance identified generically as aromatic aldehyde phenolic resin (PMN...

  3. 21 CFR 177.2510 - Polyvinylidene fluoride resins.

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 2009-04-01 true Polyvinylidene fluoride resins. 177.2510 Section 177.2510...Repeated Use § 177.2510 Polyvinylidene fluoride resins. Polyvinylidene fluoride resins may be safely used as articles...

  4. 21 CFR 177.2355 - Mineral reinforced nylon resins.

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 2009-04-01 true Mineral reinforced nylon resins. 177.2355 Section 177.2355 Food...Repeated Use § 177.2355 Mineral reinforced nylon resins. Mineral reinforced nylon resins identified in paragraph (a) of...

  5. Template method synthesis of mesoporous carbon spheres and its applications as supercapacitors

    OpenAIRE

    Wilgosz, Karolina; Chen, Xuecheng; Kierzek, Krzysztof; Machnikowski, Jacek; Ryszard J. Kalenczuk; Mijowska, Ewa

    2012-01-01

    Mesoporous carbon spheres (MCS) have been fabricated from structured mesoporous silica sphere using chemical vapor deposition (CVD) with ethylene as a carbon feedstock. The mesoporous carbon spheres have a high specific surface area of 666.8?m2/g and good electrochemical properties. The mechanism of formation mesoporous carbon spheres (carbon spheres) is investigated. The important thing is a surfactant hexadecyl trimethyl ammonium bromide (CTAB), which accelerates the process of carbon depos...

  6. Recent progress in mesoporous titania materials: adjusting morphology for innovative applications

    OpenAIRE

    Juan L Vivero-Escoto, Ya-Dong Chiang, Kevin C-W Wu and Yusuke Yamauchi

    2012-01-01

    This review article summarizes recent developments in mesoporous titania materials, particularly in the fields of morphology control and applications. We first briefly introduce the history of mesoporous titania materials and then review several synthesis approaches. Currently, mesoporous titania nanoparticles (MTNs) have attracted much attention in various fields, such as medicine, catalysis, separation and optics. Compared with bulk mesoporous titania materials, which are above a micrometer...

  7. Study of Novel Oligomeric Azo Dyes

    OpenAIRE

    Patel J. R.; Kiran Nimavat; Kartik Vyas

    2012-01-01

    Diazotization of p-anisidine and coupling with 3-amino-phenol-Formaldehyde (APF) resin give oligomaric azo dye TAPF, based on 3-amino-phenol-Formaldehyde (APF) polymer. The TAPF was then treated with 5-chloro methyl-8-quinolinol hydrochloride in the presence of a THF in alkaline medium (pH 9-10) at room temperature for 7 hrs. The resultant oligomaric ligand designated as azo polyphenol-formaldehyde-5-chloromethyl-8-quinolinol (AAPFQ) was characterized by elemental analysis, IR spectral studie...

  8. The Sequestration and Protection of Organic Matter Within Mineral Mesopores

    Science.gov (United States)

    Zimmerman, A. R.; Chorover, J. D.; Komarneni, S.; Brantley, S. L.

    2002-12-01

    Organic matter-mineral interactions may explain diverse phenomena such as sequestration of pollutants and preservation of organic matter in soils and sediments. Mineral mesopores (2-50 nm diameter) may sequester organic matter (natural and pollutant) and protect it from microbial and fungal enzymatic degradation in soils and sediments. To test this idea, we carried out batch aqueous experiments to examine adsorption of amino acid monomers and polymers onto synthetic mesoporous and nonporous alumina and silica with controlled intraparticle porosity with similar surface chemistry. All amino acid monomers and polymers smaller than about one-third the pore diameter exhibited significantly greater adsorption (on a surface area normalized basis) to mesoporous alumina (8.2 nm mean pore diameter) and silica (3.4 nm mean pore diameter) versus nonporous phases. Amino acid polymers (lysozyme, albumin, g-globulin) of sizes approaching and larger than the mesopores, however, exhibited greater adsorption to the nonporous phases indicating their exclusion from the internal surfaces of the mesoporous minerals. Further, we observed a sharp decrease in the surface area of the mesoporous materials after adsorption of these proteins indicating blockage of pore openings. These results provide a potential mechanism for the selective sequestration of sedimentary organic matter. To test whether these pore-sequestered materials are likely to be preserved, we incubate mesoporous and nonporous minerals and sorbed organic matter (model amino acid compounds and natural organic matter extracts) in solutions containing bacterial or fungal derived enzymes. The amount of degradation of sorbed organic matter is detected by measuring sediment TOC before and after the experiment while qualitative changes are indicated by diffuse reflectance infrared Fourier transform (DRIFT) spectra. We expect that small organic compounds sorbed within pores will be protected from degradation while organic matter sorbed to nonporous mineral will be minimally protected. An overall bias toward the preservation of lower molecular weight organic matter is predicted. These results highlight the importance of particle surface morphology for organic matter preservation in soils and sediments.

  9. Synthesis of Mesoporous Silica Microspheres by Using Polymeric Surfactant

    International Nuclear Information System (INIS)

    Since mesoporous M41S families were discovered by Mobile Corporation researchers, synthesis of the mesoporous materials with novel morphologies and pore structures because of their potential applications as versatile catalysts, catalyst supports, separation media, and hosts for clusters and have been reported through various synthetic strategies by using surfactant templated process. Spherical morphology has become quite attractive in many applications such as a packing material in chromatography or as an easy-to-handle form for catalytic purposes. Based on modified Stober process, the synthesis of the spherical mesoporous silica particles with sub-micrometer size has been reported. However, Modified-Stober process in a homogeneous environment for preparing mesoporous silica spheres rarely produce silica particles larger than 10 ?m. Recently, Kosuge and Singh have directly synthesized the silica microspheres of 30 ? 50 ?m in diameter by using n-alkylamine (C12-NH2) and ethanol in an acidic medium at room temperature. Also, Stucky et al. reported the slow sol-gel surfactant template synthesis of mesoporous silica spheres larger than 100 ?m. In our previous study, we reported a new robust surfactant-template synthesis strategy for the stable suspension of large silica microspheres by introducing an additional cosurfactant. Bis(2- ethylhexyl)phosphate (BEHP) as a cosurfactant played a key role in suspension stabilization without distorting the spherical morphology as well as in the formation of uniform pore structures. Although most mesoporous silica particles above mentioned possess the narrow pore size distribution, high surface area, and large pore volume, their pore structure consists to the single pore system. Recently, mesoporous materials with bimodal pore systems are of considerable interest for applications in catalysis and separations, since they combine the benefits of each pore size regime

  10. The solidification of spent resin

    International Nuclear Information System (INIS)

    A quasi-steady apparatus was applied to measure the thermal conductivity of solids ranging in size for 0.3 to 200 L, and temperature distributions in the solids were recorded during the curing, and theoretical equation for conduction in a cylindrical form with uniform energy generation was established to define the thermal state of reaction. The heat of reaction calculated from the theoretical equation with experimental values for the maximum temperature and thermal conductivity agrees very well with the data reported. The relationships among heat of reaction and amount of curing agent, retardant, loading of spent resin, and water were established

  11. Polyimide Resins Resist Extreme Temperatures

    Science.gov (United States)

    2009-01-01

    Spacecraft and aerospace engines share a common threat: high temperature. The temperatures experienced during atmospheric reentry can reach over 2,000 F, and the temperatures in rocket engines can reach well over 5,000 F. To combat the high temperatures in aerospace applications, Dr. Ruth Pater of Langley Research Center developed RP-46, a polyimide resin capable of withstanding the most brutal temperatures. The composite material can push the service temperature to the limits of organic materials. Designed as an environmentally friendly alternative to other high-temperature resins, the RP-46 polyimide resin system was awarded a 1992 "R&D 100" award, named a "2001 NASA Technology of the Year," and later, due to its success as a spinoff technology, "2004 NASA Commercial Invention of the Year." The technology s commercial success also led to its winning the Langley s "Paul F. Holloway Technology Transfer Award" as well as "Richard T. Whitcom Aerospace Technology Transfer Award" both for 2004. RP-46 is relatively inexpensive and it can be readily processed for use as an adhesive, composite, resin molding, coating, foam, or film. Its composite materials can be used in temperatures ranging from minus 150 F to 2,300 F. No other organic materials are known to be capable of such wide range and extreme high-temperature applications. In addition to answering the call for environmentally conscious high-temperature materials, RP-46 provides a slew of additional advantages: It is extremely lightweight (less than half the weight of aluminum), chemical and moisture resistant, strong, and flexible. Pater also developed a similar technology, RP-50, using many of the same methods she used with RP-46, and very similar in composition to RP-46 in terms of its thermal capacity and chemical construction, but it has different applications, as this material is a coating as opposed to a buildable composite. A NASA license for use of this material outside of the Space Agency as well as additional government-funded testing proved that RP-46 is even more exceptional than originally thought.

  12. Properties of the Carboxylate ion exchange resins; Karboxylatjonbytarmassans egenskaper

    Energy Technology Data Exchange (ETDEWEB)

    Allard, Bert; Dario, Maarten [Oerebro Univ. (Sweden); Boren, Hans [Linkoepings Univ. (Sweden); Torstenfelt, Boerje [Swedpower, Stockholm (Sweden); Puigdomenech, Ignasi; Johansson, Claes [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    2002-09-01

    Weakly acidic, carboxylic resin has been selected, together with strong base anion resins, for water purification at the Forsmark 1 and 2 reactors. For the strong (but not the weak) ion exchange resin the Nuclear Power Inspectorate has given permission to dispose the spent resins in the SFR 1 (the Final Repository for Radioactive Operational Waste). This report gives a review of the carboxylic resins and comes to the conclusion that the resins are very stable and that there should not exist any risks for increased leaching of radionuclides from SFR 1 if these resins are disposed (compared to the strong resins)

  13. 21 CFR 177.2500 - Polyphenylene sulfone resins.

    Science.gov (United States)

    2010-04-01

    ... consist of basic resin produced by reacting polyphenylene sulfide with peracetic acid such that the... optional adjuvant substances required in the production of such basic resins. These optional...

  14. 75 FR 59997 - Shipping; Technical, Organizational, and Conforming Amendments

    Science.gov (United States)

    2010-09-29

    ...mixtures (having 10% Benzene or more) 0 g. Butylbenzene, see Alky(C3-C4)benzenes 0 h. Butyl phenol, Formaldehyde resin in Xylene 0 i. Butyl toluene 0 j. Cymene 0 k. Decylbenzene, see Alkyl(C9+) benzenes 0 l....

  15. Method for making adhesive from biomass

    Science.gov (United States)

    Russell, J.A.; Riemath, W.F.

    1984-03-30

    A method is described for making adhesive from biomass. A liquefaction oil is prepared from lignin-bearing plant material and a phenolic fraction is extracted therefrom. The phenolic fraction is reacted with formaldehyde to yield a phenol-formaldehyde resin. 2 figures.

  16. Novel mesoporous composites based on natural rubber and hexagonal mesoporous silica: Synthesis and characterization

    International Nuclear Information System (INIS)

    The present study is the first report on the synthesis and characterization of mesoporous composites based on natural rubber (NR) and hexagonal mesoporous silica (HMS). A series of NR/HMS composites were prepared in tetrahydrofuran via an in situ sol–gel process using tetraethylorthosilicate as the silica precursor. The physicochemical properties of the composites were characterized by various techniques. The effects of the gel composition on the structural and textural properties of the NR/HMS composites were investigated. The Fourier-transform infrared spectroscopy (FTIR) and 29Si magic angle spinning nuclear magnetic resonance (29Si MAS NMR) results revealed that the surface silanol groups of NR/HMS composites were covered with NR molecules. The powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) data indicated an expansion of the hexagonal unit cell and channel wall thickness due to the incorporation of NR molecules into the mesoporous structure. NR/HMS composites also possessed nanosized particles (?79.4 nm) as confirmed by scanning electron microscopy (SEM) and particle size distribution analysis. From N2 adsorption–desorption measurement, the NR/HMS composites possessed a high BET surface area, large pore volume and narrow pore size distribution. Further, they were enhanced hydrophobicity confirmed by H2O adsorption–desorption measurement. In addition, the mechanistic pathway of the NR/HMS composite formation was proposed. - Highlights: • NR molecules were incorporated into hexagonal meso-structure of HMS. • NR/HMS composites exhibited an expanded unit cell and channel wall thickness. • Nanosized NR/HMS composites with a lower particle size range were obtained. • NR/HMS had high surface area, large pore volume and narrow pore size distribution. • NR/HMS composites displayed an enhanced hydrophobicity

  17. Experience with NuResin, a mobile ion exchange resin reprocessing system

    International Nuclear Information System (INIS)

    Ion exchange resin used in condensate polishing, steam generator blowdown, and radwaste systems is a major contributor to the volume of low-level waste (LLW) at operating nuclear plants. Plant regeneration systems for resins use large quantities of demineralized water for cleaning, separating, and regenerating resins. These systems generate a tremendous volume of LLW from boiling water reactors (BWRs) and those pressurized water reactors (PWRs) that have experienced steam generator tube leaks. At essentially all BWRs and those PWRs that replace rather than regenerate condensate polishing resin, the LLW volume contribution from the resin alone is significant. This report describes a process for the treatment of resins with the objective of returning the resin to service

  18. delayed asthma bronchiale due to epoxy resin

    DEFF Research Database (Denmark)

    Authried, Georg; Al-Asadi, Haifaa; Møller, Ulla; Sherson, David Lee

    2013-01-01

    Epoxy resin is a low molecular weight agent, which can cause both acute and delayed allergic reactions. However, it is known causing skin reactions with direct or airborne contact. Rarely it can cause airway reactions like asthma bronchiale. We describe a case of a windmill worker who developed delayed asthma bronchiale due to airborne contact with epoxy resin.

  19. Overview on resins available in microlithography

    International Nuclear Information System (INIS)

    Lithographic equipments using electrons and X radiation are developed. Velocity and resolution requirements fix the nature of the material to irradiate. Circuit making principles are recalled here; resists (organic polymers) are employed for it. The different types of resins and then needed characteristics are reviewed here. In the scope of electron sensitive resins methyl polymethacrylate and derivative and its copolymers (and copolymers of methacrylonitrile) and reticulated copolymers are studied. Polysulfones are also presented (poly(buten-1 sulfone), poly(styrene sulfone), poly(methyl-1 cyclopentene-1 sulfone). The interest in photosensitive resins (such as AZ) as electron sensitive resins is recalled. In the field of negative resins, the polyepoxyds, polystyrene and halogenated derivates from polystyrene (CMS and PCMS), the poly(vinyl-2 naphtalene) and its derivatives (PSTTF) are presented. The X radiation sensitive resins are also reviewed: the methyl polymethacrylate and its halogenated derivates, the acrylic homopolymers and copolymers (example of poly(acrylate of chlorinated alcoyls). The resins developable by plasma are mentioned. At last, for photosensitive resins, the diazide polydiene systems are presented together with systems diazo-2 2H-naphtalenone-1. The systems with salt photolysis are just recalled

  20. Epoxidation of linseed oil-Alkyd resins

    International Nuclear Information System (INIS)

    Three types of different linseed oil-alkyd resin ( Alk (I), Alk (II), and Alk (III) ) were prepared with the calculated amounts of mono glycerides and adipic acid (1:1, 1:2, and 2:1 Eq.Wt) respectively via monoglyceride method. The obtained alkyd resins were epoxidized via reaction with the calculated quantities of peracetic acid, which was prepared by the reaction of acetic anhydride with H2O2. Epoxidation occurred with the ratio (1: 1, 1 :3, and 1:6 Eq. Wt) of alkyd to peracetic acid. The effect of reaction time on the epoxy group content was measured during the epoxidation process. The prepared alkyd resins were analyzed by IR and H1NMR. The metal coated film properties of epoxidized alkyd resins were compared with those of unmodified alkyd resins. It was observed that the coating films of epoxidized alkyd resins have better in drying properties, hardness, adhesion, impact and flexibility than those of un epoxidized alkyd resins. The flammability properties of the paper coated films for the prepared brominated epoxidized alkyd resins were found to be fire retardant

  1. Ion exchange resins for uranium recovery

    International Nuclear Information System (INIS)

    The density and capacity of macroporous ion exchange resins are increased by incorporating therein at least one of titania hydrate, zirconia hydrate, hydrated titanium phosphorous, and hydrated zirconium phosphate hydrates. Such resin composites are useful, e.g., in removing uranium values from aqueous solutions

  2. 21 CFR 177.1655 - Polysulfone resins.

    Science.gov (United States)

    2010-04-01

    ...finished resins have a minimum number average molecular weight of 15,000, as determined by osmotic pressure in monochlorobenzene; or...Polysulfone resins, when extracted at reflux temperatures for 6 hours with the solvents—distilled water, 50 percent (by...

  3. Volumetric polymerization shrinkage of contemporary composite resins

    Directory of Open Access Journals (Sweden)

    Halim Nagem Filho

    2007-10-01

    Full Text Available The polymerization shrinkage of composite resins may affect negatively the clinical outcome of the restoration. Extensive research has been carried out to develop new formulations of composite resins in order to provide good handling characteristics and some dimensional stability during polymerization. The purpose of this study was to analyze, in vitro, the magnitude of the volumetric polymerization shrinkage of 7 contemporary composite resins (Definite, Suprafill, SureFil, Filtek Z250, Fill Magic, Alert, and Solitaire to determine whether there are differences among these materials. The tests were conducted with precision of 0.1 mg. The volumetric shrinkage was measured by hydrostatic weighing before and after polymerization and calculated by known mathematical equations. One-way ANOVA (a or = 0.05 was used to determine statistically significant differences in volumetric shrinkage among the tested composite resins. Suprafill (1.87±0.01 and Definite (1.89±0.01 shrank significantly less than the other composite resins. SureFil (2.01±0.06, Filtek Z250 (1.99±0.03, and Fill Magic (2.02±0.02 presented intermediate levels of polymerization shrinkage. Alert and Solitaire presented the highest degree of polymerization shrinkage. Knowing the polymerization shrinkage rates of the commercially available composite resins, the dentist would be able to choose between using composite resins with lower polymerization shrinkage rates or adopting technical or operational procedures to minimize the adverse effects deriving from resin contraction during light-activation.

  4. PENGARUH STRUKTUR PORI TERHADAP KAPASITANSI ELEKTRODA SUPERKAPASITOR YANG DIBUAT DARI KARBON NANOPORI

    Directory of Open Access Journals (Sweden)

    Teguh Ariyanto

    2012-05-01

    Full Text Available THE EFFECT OF PORE STRUCTURE ON THE ELECTRODE CAPACITANCE OF SUPERCAPACITOR PREPARED BY NANOPOROUS CARBON. Nanoporous carbons, due to high specific surface area, high pore accessibility, and relatively low cost, have been used as material electrode supercapacitors. In this work, the influence of pore structure of nanoporous carbons on the specific capacitance of supercapacitors was examined. Nanoporous carbons with several types of pore structure were prepared by carbonization of phenolic resin produced by polymeric condensation of phenolic compound with formaldehyde. Furthermore, ethylene glycol, as a filler, was added in the phenolic resin polymerization to increase the mesoporosity of nanoporous carbon. The nanoporous carbons produced were characterized for their surface morphology, specific internal surface area (BET method, and pore structure. Samples were used as electrode material in supercapacitor and specific capacitances were characterized by galvanostatic test using 30% KOH aqueous solution as electrolyte. The capacitance test of supercapacitors exhibited that increasing mesoporosity increase specific capacitance value of supercapacitors. The highest specific capacitance of 336 F/g was obtained by using mesoporous carbon produced by carbonization of resorcinol phenol formaldehyde ethylene glycol (C-RPFEG2 as electrode material of supercapacitors.  Karbon nanopori dikarenakan memiliki luas permukaan internal yang tinggi, aksesibilitas pori yang baik, dan relatif murah telah digunakan sebagai material elektroda superkapasitor. Pada penelitian ini, pengaruh struktur pori dari karbon nanopori terhadap kapasitansi spesifik superkapasitor telah dipelajari. Karbon berpori dengan berbagai struktur pori dibuat dengan cara karbonisasi phenolic resin yang dibuat dengan cara polimerisaasi kondensasi senyawa phenolic dengan formaldehyde. Selain itu, etilen glikol sebagai filler ditambahkan pada saat polimerisasi phenolic resin untuk meningkatkan mesoporositas dari karbon nanopori. Karbon yang diperoleh dikarakterisasi berupa morfologi permukaan, luas permukaan spesifik (metode BET, dan struktur pori. Karbon tersebut kemudian digunakan sebagai material elektroda superkapasitor dan kapasitansi spesifik dikarakterisasi dengan tes galvanostatik menggunakan KOH 30% sebagai elektrolit. Uji kapasitansi superkapasitor menunjukkan bahwa meningkatnya mesoporositas karbon nanopori akan meningkatkan nilai kapasitansi spesifik. Kapasitansi spesifik tertinggi sebesar 336 F/g diperoleh jika menggunakan karbon mesopori hasil karbonisasi resorcinol phenol formaldehyde ethylene glycol (C-RPFEG2 sebagai material elektroda superkapasitor.

  5. Electrodialytic decontamination of spent ion exchange resins

    International Nuclear Information System (INIS)

    Development of a novel electrodialytic decontamination process for the selective removal of radioactive Cs from spent ion exchange resins containing large amounts of Li is described. The process involves passage of a dc electric current through a bed of the spent ion exchange resin in a specially designed electrodialytic cell. The radiocesium so removed from a volume of the spent resin is concentrated onto a much smaller volume of a Cs selective sorbent to achieve a significant radioactive waste volume reduction. Technical feasibility of the electrodialytic resin decontamination process has been demonstrated on a bench scale with a batch of simulated spent ion exchange resin and using potassium cobalt ferrocyanide as the Cs selective sorbent. A volume reduction factor between 10 and 17 has been estimated. The process appears to be economically attractive. Improvements in process economics can be expected from optimization of the process. Other possible applications of the EDRD process have been identified

  6. Preparation and Characterization of Mesoporous Iron-Oxide

    Directory of Open Access Journals (Sweden)

    XUE Hong-Tao,SHEN Shui-Fa,PAN Hai-Bo,XIE Chang-Huai

    2009-05-01

    Full Text Available Transition metal oxides are easy to form insoluble oligomer in reaction because of complicated oxidation states, so it is difficult to obtain the desired mesoporous structure. To resolve the problem, mesoporous iron oxide was synthesized by reacting a micellar phase of sodium dodecyl sulfate (SDS with iron polymer solution which was prepared by controlling the proportion of sodium hydroxide and ferric chloride. Crystal structure and surface structure of the mesoporous iron oxide was characterized by powder X-ray diffraction (XRD, Fourier transform ª² infrared spectroscopy (FT-IR, thermogravimetric analyse(TGA, Nitrogen adsorptionª²desorption method and so on. The results show that mesoporous ¦?Fe2O3 can be obtained after calcining at 450¡?ith OH-/Fe3+ ratio of 2.0. Its surface area is 146.5m2¡¤g-1, BJH average diameter is 6.9nm, pore volume is 0.27cm3¡¤g-1. The asª²prepared mesoporous iron oxide has better thermal stability, it still has surface area of 110.2m2¡¤g-1 after calcination at 550¡?

  7. Organized thiol functional groups in mesoporous core shell colloids

    Energy Technology Data Exchange (ETDEWEB)

    Marchena, Martin H. [Gerencia Quimica, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica (CNEA), Avda. Gral. Paz 1499, B1650KNA Buenos Aires (Argentina); Granada, Mara [Centro Atomico Bariloche-CNEA, 8400 San Carlos de Bariloche (Argentina); Instituto Balseiro-Centro Atomico Bariloche-CNEA, San Carlos de Bariloche 8400 (Argentina); Bordoni, Andrea V. [Gerencia Quimica, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica (CNEA), Avda. Gral. Paz 1499, B1650KNA Buenos Aires (Argentina); Joselevich, Maria [Asociacion Civil Expedicion Ciencia, Cabrera 4948, C1414BGP Buenos Aires (Argentina); Troiani, Horacio [Centro Atomico Bariloche-CNEA, 8400 San Carlos de Bariloche (Argentina); Instituto Balseiro-Centro Atomico Bariloche-CNEA, San Carlos de Bariloche 8400 (Argentina); Williams, Federico J. [DQIAQyF-INQUIMAE FCEN, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon II, C1428EHA Buenos Aires (Argentina); Wolosiuk, Alejandro, E-mail: wolosiuk@cnea.gov.ar [Gerencia Quimica, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica (CNEA), Avda. Gral. Paz 1499, B1650KNA Buenos Aires (Argentina)

    2012-03-15

    The co-condensation in situ of tetraethoxysilane (TEOS) and mercaptopropyltrimethoxysilane (MPTMS) using cetyltrimethylammonium bromide (CTAB) as a template results in the synthesis of multilayered mesoporous structured SiO{sub 2} colloids with 'onion-like' chemical environments. Thiol groups were anchored to an inner selected SiO{sub 2} porous layer in a bilayered core shell particle producing different chemical regions inside the colloidal layered structure. X-Ray Photoelectron Spectroscopy (XPS) shows a preferential anchoring of the -SH groups in the double layer shell system, while porosimetry and simple chemical modifications confirm that pores are accessible. We can envision the synthesis of interesting colloidal objects with defined chemical environments with highly controlled properties. - Graphical abstract: Mesoporous core shell SiO{sub 2} colloids with organized thiol groups. Highlights: Black-Right-Pointing-Pointer Double shell mesoporous silica colloids templated with CTAB. Black-Right-Pointing-Pointer Sequential deposition of mesoporous SiO{sub 2} layers with different chemistries. Black-Right-Pointing-Pointer XPS shows the selective functionalization of mesoporous layers with thiol groups.

  8. Near-field radiative heat transfer in mesoporous alumina

    International Nuclear Information System (INIS)

    The thermal conductivity of mesoporous material has aroused the great interest of scholars due to its wide applications such as insulation, catalyst, etc. Mesoporous alumina substrate consists of uniformly distributed, unconnected cylindrical pores. Near-field radiative heat transfer cannot be ignored, when the diameters of the pores are less than the characteristic wavelength of thermal radiation. In this paper, near-field radiation across a cylindrical pore is simulated by employing the fluctuation dissipation theorem and Green function. Such factors as the diameter of the pore, and the temperature of the material are further analyzed. The research results show that the radiative heat transfer on a mesoscale is 2?4 orders higher than on a macroscale. The heat flux and equivalent thermal conductivity of radiation across a cylindrical pore decrease exponentially with pore diameter increasing, while increase with temperature increasing. The calculated equivalent thermal conductivity of radiation is further developed to modify the thermal conductivity of the mesoporous alumina. The combined thermal conductivity of the mesoporous alumina is obtained by using porosity weighted dilute medium and compared with the measurement. The combined thermal conductivity of mesoporous silica decreases gradually with pore diameter increasing, while increases smoothly with temperature increasing, which is in good agreement with the experimental data. The larger the porosity, the more significant the near-field effect is, which cannot be ignored. (paper)

  9. Solidification of ion exchange resin wastes

    International Nuclear Information System (INIS)

    Solidification media investigated included portland type I, portland type III and high alumina cements, a proprietary gypsum-based polymer modified cement, and a vinyl ester-styrene thermosetting plastic. Samples formulated with hydraulic cement were analyzed to investigate the effects of resin type, resin loading, waste-to-cement ratio, and water-to-cement ratio. The solidification of cation resin wastes with portland cement was characterized by excessive swelling and cracking of waste forms, both after curing and during immersion testing. Mixed bed resin waste formulations were limited by their cation component. Additives to improve the mechanical properties of portland cement-ion exchange resin waste forms were evaluated. High alumina cement formulations dislayed a resistance to deterioration of mechanical integrity during immersion testing, thus providing a significant advantage over portland cements for the solidification of resin wastes. Properties of cement-ion exchange resin waste forms were examined. An experiment was conducted to study the leachability of 137Cs, 85Sr, and 60Co from resins modified in portland type III and high alumina cements. The cumulative 137Cs fraction release was at least an order of magnitude greater than that of either 85Sr or 60Co. Release rates of 137Cs in high alumina cement were greater than those in portland III cement by a factor of two.Compressive strength and leach testing were conducted for resin wastes solidified with polymer-modified gypsum based cement. 137Cs, 85Sr, and 60Co fraction releases were about one, two and three orders of magnitude higher, respectively, than in equivalent portland type III cement formulations. As much as 28.6 wt % dry ion exchange resin was successfully solidified using vinyl ester-styrene compared with a maximum of 25 wt % in both portland and gypsum-based cement

  10. FABRICATION AND STUDY OF LIGNOCELLULOSIC HIBISCUS SABDARIFFA FIBER REINFORCED POLYMER COMPOSITES

    OpenAIRE

    Amar Singh Singha,; Vijay Kumar Thakur

    2008-01-01

    Fabrication of polymer composites reinforced with lignocellulosic materials has increased considerably during the last few years. This work reports the synthesis of natural fiber reinforced phenol-formaldehyde (PF) resin matrix based polymer composite using a compression molding technique. Initially the PF resin was prepared by varying the concentration of formaldehyde with a fixed weight of phenol. Polymeric resin of different P: F ratios were subjected for optimization of their mechanical p...

  11. Enhancing the Porosity of Mesoporous Carbon-Templated ZSM-5 by Desilication

    DEFF Research Database (Denmark)

    Holm, Martin Spangsberg; Egeblad, Kresten

    2008-01-01

    A tunable desilication protocol applied on a mesoporous ZSM-5 zeolite synthesized by carbon-templating is reported. The strategy enables a systematic manufacture of zeolite catalysts with moderate to very high mesoporosities. Coupling carbon-templating and desilication thus allow for more than a doubling of the original mesopore volume and mesopore surface area. The porosity effect arising from various treatment times and base amounts in the media has been thoroughly mapped. Initially, small mesopores are created, and as desilication strength increases the average mesopore size enhances. Crystallinity of the treated samples is retained, and electron microscopy indicates solely intracrystalline mesoporosity. (

  12. Highly Loaded Mesoporous Silica/Nanoparticle Composites and Patterned Mesoporous Silica Films

    Science.gov (United States)

    Kothari, Rohit; Hendricks, Nicholas R.; Wang, Xinyu; Watkins, James J.

    2014-03-01

    Novel approaches for the preparation of highly filled mesoporous silica/nanoparticle (MS/NP) composites and for the fabrication of patterned MS films are described. The incorporation of iron platinum NPs within the walls of MS is achieved at high NP loadings by doping amphiphilic poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) (Pluronic®) copolymer templates via selective hydrogen bonding between the pre-synthesized NPs and the hydrophilic portion of the block copolymer. The MS is then synthesized by means of phase selective condensation of tetraethylorthosilicate (TEOS) within the NP loaded block copolymer templates dilated with supercritical carbon dioxide (scCO2) followed by calcination. For patterned films, microphase separated block copolymer/small molecule additive blends are patterned using UV-assisted nanoimprint lithography. Infusion and condensation of a TEOS within template films using ScCO2 as a processing medium followed by calcination yields the patterned MS films. Scanning electron microscopy is used characterize pattern fidelity and transmission electron microscopy analysis confirms the presence of the mesopores. Long range order in nanocomposites is confirmed by low angle x-ray diffraction.

  13. Electrochromic and optical properties of mesoporous tungsten oxide films

    Energy Technology Data Exchange (ETDEWEB)

    Ozkan, Esra; Lee, Se-Hee; Liu, Ping; Tracy, C. Edwin; Pitts, J. Roland; Deb, Satyen K. [National Renewable Energy Laboratory, 1617 Cole Boulevard, 80401 Golden, CO (United States); Tepehan, Fatma Z. [Department of Physics, Faculty of Science and Letters, Istanbul Technical University, Maslak, 80626 Istanbul (Turkey)

    2002-07-01

    Standard and mesoporous sol-gel tungsten oxide thin films were prepared by a spin-coating technique from an ethanolic solution of tungsten hexachloride. A block copolymer (BASF Pluronic p{sub 123}) was employed as a template to generate the mesoporous structure. An ultraviolet (UV) illumination method was employed to remove the polymer templates at room temperature. The electrochromic and optical properties of the mesoporous films are described and compared to standard sol-gel tungsten oxide films. Results are also presented on the samples prepared by thermal treatment. We demonstrate that the UV illumination/ozone treatment is a superior method to remove templates which enables us to more effectively investigate the effect of mesoporosity on the electrokinetics of ion insertion into tungsten oxide films.

  14. Synthesis of mesoporous silica microsphere from dual surfactant

    Directory of Open Access Journals (Sweden)

    Venkatathri Narayanan

    2008-12-01

    Full Text Available A new procedure is reported to synthesis mesoporous silica micro sphere for the first time. In these method two surfactants namely Span 80 and Tween 80 were used. Small angle X ray diffraction and N2 adsorption analysis shows the synthesized material has mesoporous property. The material has spherical morphology with 1-10 µm particle size. Beside the material found to have microcapsule property as observed from the Transmission electron microscopy. The Fourier transform Infrared spectroscopic analysis reveals that the materials are similar to other mesoporous materials. We also encapsulated an UV-absorber Ibuprofen inside the microcapsule, by mixing it before the synthesis. This shows a possibility of the materials in cosmetic applications.

  15. Synthesis of mesoporous silica microsphere from dual surfactant

    Scientific Electronic Library Online (English)

    Venkatathri, Narayanan.

    2008-12-01

    Full Text Available A new procedure is reported to synthesis mesoporous silica micro sphere for the first time. In these method two surfactants namely Span 80 and Tween 80 were used. Small angle X ray diffraction and N2 adsorption analysis shows the synthesized material has mesoporous property. The material has spheric [...] al morphology with 1-10 µm particle size. Beside the material found to have microcapsule property as observed from the Transmission electron microscopy. The Fourier transform Infrared spectroscopic analysis reveals that the materials are similar to other mesoporous materials. We also encapsulated an UV-absorber Ibuprofen inside the microcapsule, by mixing it before the synthesis. This shows a possibility of the materials in cosmetic applications.

  16. Polymorphism of the glass former ethanol confined in mesoporous silicon

    CERN Document Server

    Henschel, Anke; Huber, Patrick; 10.1080/09500831003766999

    2010-01-01

    X-ray diffraction patterns of ethanol confined in parallel-aligned channels of approx. 10 nm diameter and 50 micrometer length in mesoporous silicon have been recorded as a function of filling fraction, temperature and for varying cooling and heating rates. A sorption isotherm, recorded in the liquid state, indicates a three monolayer thick, strongly adsorbed wall layer and a capillary condensed fraction of molecules in the pore center. Though the strongly adsorbed film remains in an amorphous state for the entire temperature range investigated, the capillary condensed molecules reproduce the polymorphism of bulk solid ethanol, that is the formation of either crystalline or glass-like states as a function of cooling rate. The critical rate necessary to achieve a vitrification in the mesopores is, however, at least two orders of magnitude smaller than in the bulk state. This finding can be traced both to pure geometrical constraints and quenched disorder effects, characteristic of confinement in mesoporous sil...

  17. Adsorption of vitamin E on mesoporous titania nanocrystals

    International Nuclear Information System (INIS)

    Tri-block nonionic surfactant and titanium chloride were used as starting materials for the synthesis of mesoporous titania nanocrystallite powders. The main objective of the present study was to examine the synthesis of mesoporous titania nanocrystals and the adsorption of vitamin E on those nanocrystals using X-ray diffraction (XRD), transmission electron microscopy, and nitrogen adsorption and desorption isotherms. When the calcination temperature was increased to 300 oC, the reflection peaks in the XRD pattern indicated the presence of an anatase phase. The crystallinity of the nanocrystallites increased from 80% to 98.6% with increasing calcination temperature from 465 oC to 500 oC. The N2 adsorption data and XRD data taken after vitamin E adsorption revealed that the vitamin E molecules were adsorbed in the mesopores of the titania nanocrystals.

  18. Adsorption of vitamin E on mesoporous titania nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Shih, C.J., E-mail: cjshih@kmu.edu.tw [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Lin, C.T.; Wu, S.M. [School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China)

    2010-07-15

    Tri-block nonionic surfactant and titanium chloride were used as starting materials for the synthesis of mesoporous titania nanocrystallite powders. The main objective of the present study was to examine the synthesis of mesoporous titania nanocrystals and the adsorption of vitamin E on those nanocrystals using X-ray diffraction (XRD), transmission electron microscopy, and nitrogen adsorption and desorption isotherms. When the calcination temperature was increased to 300 {sup o}C, the reflection peaks in the XRD pattern indicated the presence of an anatase phase. The crystallinity of the nanocrystallites increased from 80% to 98.6% with increasing calcination temperature from 465 {sup o}C to 500 {sup o}C. The N{sub 2} adsorption data and XRD data taken after vitamin E adsorption revealed that the vitamin E molecules were adsorbed in the mesopores of the titania nanocrystals.

  19. Synthesis of highly ordered mesoporous Co3O4 for gas sensing.

    Science.gov (United States)

    Su, D W; Liu, H; Ahn, H J; Wang, G X

    2013-05-01

    Highly ordered mesoporous Co3O4 nanostructures were prepared using SBA-15 silica as hard templates. The mesoporous structures were characterized by X-ray diffraction, high resolution transmission electron microscopy, and N2 adsorption/desorption isotherm analysis. The results demonstrated that the as-prepared mesoporous Co3O4 has an ordered P6mm symmetric mesoporous structure. The optical absorption properties of the mesoporous Co3O4 were investigatted by UV-Vis spectroscopy and the results indicate that the mesoporous Co3O4 materials are semiconducting with direct band gaps of 2, 1.385 and 0.38 eV. The gas-sensing performance of the mesoporous Co3O4 was tested towards a series of typical solvents. They demonstrated a good sensing performance towards these vapour with rapid response and high sensitivity at low operating temperature. PMID:23858858

  20. Controlled drug release from bifunctionalized mesoporous silica

    International Nuclear Information System (INIS)

    Serial of trimethylsilyl-carboxyl bifunctionalized SBA-15 (TMS/COOH/SBA-15) have been studied as carriers for controlled release of drug famotidine (Famo). To load Famo with large capacity, SBA-15 with high content of carboxyl groups was successfully synthesized by one-pot synthesis under the assistance of KCl. The mesostructure of carboxyl functionalized SBA-15 (COOH/SBA-15) could still be kept even though the content of carboxyl groups was up to 57.2%. Increasing carboxyl content could effectively enhance the loading capacity of Famo. Compared with pure SBA-15, into which Famo could be hardly adsorbed, the largest drug loading capacity of COOH/SBA-15 could achieve 396.9 mg/g. The release of Famo from mesoporous silica was studied in simulated intestine fluid (SIF, pH=7.4). For COOH/SBA-15, the release rate of Famo decreased with narrowing pore size. After grafting TMS groups on the surface of COOH/SBA-15 with hexamethyldisilazane, the release of Famo was greatly delayed with the increasing content of TMS groups. - Graphical abstract: Trimethylsilyl-carboxyl bifunctionalized SBA-15 has been studied as carrier for controlled release of drug famotidine. To load drug with large capacity, SBA-15 with high content of carboxyl groups was successfully synthesized. After grafting trimethylsilyl groups on the surface of carboxyl functionalized SBA-15, the release of Famo was greatly delayed with the increasing content of TMS groups

  1. Zirconia-silica based mesoporous desulfurization adsorbents

    Science.gov (United States)

    Palomino, Jessica M.; Tran, Dat T.; Kareh, Ana R.; Miller, Christopher A.; Gardner, Joshua M. V.; Dong, Hong; Oliver, Scott R. J.

    2015-03-01

    We report a series of mesoporous silicate sorbent materials templated by long-chain primary alkylamines that display record level of desulfurization of the jet fuel JP-8. Pure silica frameworks and those with a Si:Zr synthesis molar ratio ranging from 44:1 to 11:1 were investigated. The optimum sorbent was identified as dodecylamine-templated silica-zirconia synthesized from a gel with Si:Zr molar ratio of 15:1. With an optimized silver loading of 11 wt.%, a saturation adsorption capacity of 39.4 mgS g-1 and a silver efficiency of 1.21 molS mol Ag-1 were observed for JP-8. This sorbent displayed exceptional regenerability, maintaining 86% of its initial capacity in model fuel after solvent regeneration with diethyl ether. Low-cost, portable and reusable sorbents for the desulfurization of JP-8 jet fuel are needed to make solid oxide fuel cells (SOFCs) a reality for military power needs. SOFCs require ultra-low sulfur content fuel, which traditional desulfurization methods cannot achieve.

  2. Positronium annihilation and pore surface chemistry in mesoporous silica films

    International Nuclear Information System (INIS)

    Lifetimes of ortho-positronium in mesoporous silica films were measured before and after surface trimethylsilylation of -OH groups. Variations of positronium lifetimes in the mesopores upon the surface modification indicate that the interaction between positronium and the pore surface is weakened in the pores, whose surface is covered with -CH3 groups, in comparison with those covered with -OH groups. This is consistent with the authors' previous observation that positronium slowing down is less efficient in the pores covered with -CH3 groups. The present work demonstrates that in the porosimetric application of positron annihilation lifetime spectroscopy, the interaction between positronium and the pore surface has to be properly taken into consideration

  3. Monolithic Gyroidal Mesoporous Mixed Titanium–Niobium Nitrides

    Science.gov (United States)

    2015-01-01

    Mesoporous transition metal nitrides are interesting materials for energy conversion and storage applications due to their conductivity and durability. We present ordered mixed titanium–niobium (8:2, 1:1) nitrides with gyroidal network structures synthesized from triblock terpolymer structure-directed mixed oxides. The materials retain both macroscopic integrity and mesoscale ordering despite heat treatment up to 600 °C, without a rigid carbon framework as a support. Furthermore, the gyroidal lattice parameters were varied by changing polymer molar mass. This synthesis strategy may prove useful in generating a variety of monolithic ordered mesoporous mixed oxides and nitrides for electrode and catalyst materials. PMID:25122534

  4. Monolithic gyroidal mesoporous mixed titanium-niobium nitrides.

    Science.gov (United States)

    Robbins, Spencer W; Sai, Hiroaki; DiSalvo, Francis J; Gruner, Sol M; Wiesner, Ulrich

    2014-08-26

    Mesoporous transition metal nitrides are interesting materials for energy conversion and storage applications due to their conductivity and durability. We present ordered mixed titanium-niobium (8:2, 1:1) nitrides with gyroidal network structures synthesized from triblock terpolymer structure-directed mixed oxides. The materials retain both macroscopic integrity and mesoscale ordering despite heat treatment up to 600 °C, without a rigid carbon framework as a support. Furthermore, the gyroidal lattice parameters were varied by changing polymer molar mass. This synthesis strategy may prove useful in generating a variety of monolithic ordered mesoporous mixed oxides and nitrides for electrode and catalyst materials. PMID:25122534

  5. Macroporous silica–alumina composites with mesoporous walls

    Indian Academy of Sciences (India)

    Gautam Gundiah

    2001-04-01

    Macroporous silica–alumina composites with mesopores have been prepared by employing polymethylmethacrylate beads as templates in the presence of the cationic surfactant, N-cetyl-N,N,N-trimethylammonium bromide. The Si/Al ratio in the composites has been varied between 4.5 and 48 and the occurrence of mesopores has been verified by X-ray diffraction. The surface areas of the samples vary between 676 and 1038 m2 $g^{–1}$, with the highest value in the sample with Si/Al = 48.

  6. Near-infrared emission from mesoporous crystalline germanium

    Directory of Open Access Journals (Sweden)

    Abderraouf Boucherif

    2014-10-01

    Full Text Available Mesoporous crystalline germanium was fabricated by bipolar electrochemical etching of Ge wafer in HF-based electrolyte. It yields uniform mesoporous germanium layers composed of high density of crystallites with an average size 5-7 nm. Subsequent extended chemical etching allows tuning of crystallites size while preserving the same chemical composition. This highly controllable nanostructure exhibits photoluminescence emission above the bulk Ge bandgap, in the near-infrared range (1095-1360nm with strong evidence of quantum confinement within the crystallites.

  7. Tc-99 Ion Exchange Resin Testing

    Energy Technology Data Exchange (ETDEWEB)

    Valenta, Michelle M.; Parker, Kent E.; Pierce, Eric M.

    2010-08-01

    Pacific Northwest National Laboratory was contracted by CHPRC to evaluate the release of 99Tc from spent resin used to treat water from well 299-W15-765 and stored for several years. The key questions to be answered are: 1) does 99Tc readily release from the spent ion exchange resin after being in storage for several years; 2) if hot water stripping is used to remove the co-contaminant carbon tetrachloride, will 99Tc that has been sequestered by the resin be released; and 3) can spent resin be encapsulated into a cementitious waste form; if so, how much 99Tc would be released from the weathering of the monolith waste form? The results from the long term stability leach test results confirm that the resin is not releasing a significant amount of the sequestered 99Tc, evident by the less than 0.02% of the total 99Tc loaded being identified in the solution. Furthermore, it is possible that the measured 99Tc concentration is the result of 99Tc contained in the pore spaces of the resin. In addition to these results, analyses conducted to examine the impact of hot water on the release of 99Tc suggest that only a small percentage of the total is being released. This suggest that hot water stripping to remove carbon tetrachloride will not have a significant affect on the resin’s ability to hold-on to sequestered 99Tc. Finally, encapsulation of spent resin in a cementitious material may be a viable disposal option, but additional tests are needed to examine the extent of physical degradation caused by moisture loss and the effect this degradation process can have on the release of 99Tc.

  8. Host-guest chemistry of mesoporous silicas: precise design of location, density and orientation of molecular guests in mesopores

    Science.gov (United States)

    Sohmiya, Minoru; Saito, Kanji; Ogawa, Makoto

    2015-10-01

    Mesoporous solids, which were prepared from inorganic-surfactant mesostructured materials, have been investigated due to their very large surface area and high porosity, pore size uniformity and variation, periodic pore arrangement and possible pore surface modification. Morphosyntheses from macroscopic morphologies such as bulk monolith and films, to nanoscopic ones, nanoparticles and their stable suspension, make mesoporous materials more attractive for applications and detailed characterization. This class of materials has been studied for such applications as adsorbents and catalysts, and later on, for optical, electronic, environmental and bio-related ones. This review summarizes the studies on the chemistry of mesoporous silica and functional guest species (host-guest chemistry) to highlight the present status and future applications of the host-guest hybrids.

  9. Studies on cesium uptake by phenolic resins

    International Nuclear Information System (INIS)

    The selective removal of cesium by phenolic ion-exchange resins from highly salted alkaline radioactive solutions was studied. The resins were synthesized by alkaline polycondensation of phenol, resorcinol, catechol, and resorcinol-catechol mixture with formaldehyde and characterized for their moisture regain, ion-exchange (H+ ? Na+) capacity, and distribution coefficient (KD) for cesium. The effects of open and sealed curing of the polymers on their properties were studied. The effect of Na+, NaOH, and Cs+ concentration on the uptake of cesium by resorcinol-formaldehyde resin was investigated, in particular. The chemical, thermal, and radiation stabilities of the polymers were also studied

  10. Luminous Efficient Compositions Based on Epoxy Resin

    Directory of Open Access Journals (Sweden)

    R.S. Palaiah

    2006-07-01

    Full Text Available Magnesium/sodium nitrate illuminating compositions with epoxy resin - E 605 have beenstudied for luminosity and luminous efficiency by varying fuel oxidizer ratio and binder content.The compositions have been evaluated for impact and friction sensitivities, burn rate, thermalcharacteristics, and mechanical properties. Flame temperature and combustion products areevaluated theoretically by using REAL program. Experimental results show that, luminosity,burn rate, and calorimetric value are higher for polyester resin-based compositions. The highluminous efficiency composition is achieved with magnesium/sodium nitrate ratio of 70/30 with4 per cent epoxy resin.

  11. Advanced Fibre Reinforced Methyl Nadicimide Resins .

    Directory of Open Access Journals (Sweden)

    Sarfaraz Alam

    1996-07-01

    Full Text Available Glass/carbon/kevlar-reinforced composites were fabricated using two structurally different methl nadicimide resins. The resin content of the laminates was in the range of 32-39 per cent. Interlaminar shear strength (ILSSand flexual strength (FS depended on the structure of the methyl nadicimide resins. A significant decrease in the ILSS was observed on treatment with boiling water for 500 h and on isothermal ageing at 300 degree celsius for 100,250 and 500 h. The limiting oxygen index (LOI was the lowest for laminates based on Kevlar fabrics (i.e.54 whereas the laminates based on glass/carbon showed very high LOI(>90.

  12. Immobilisation of ion exchange resins in cement

    International Nuclear Information System (INIS)

    The removal of activity from spent decontaminating solutions eg LOMI can be achieved using organic ion exchange resins. These resins can be successfully immobilised in cement based matrices. The optimum cement system contained 10% ordinary Portland cement, 84% gg blast furnace slag, 6% microsilica with a water cement ratio of 0.5 and a dry resin loading of 36% with respect to total weight. This formulation was successfully scaled up to 200 litres giving a product with acceptable compressive strength, dimensional stability and elastic modulus. Storage of samples under water appears to have no detrimental effects on the products' properties. (author)

  13. Kinetic Study of Resin-Curing on Carbon Fiber/Epoxy Resin Composites by Microwave Irradiation

    OpenAIRE

    Daisuke Shimamoto; Yusuke Imai, Yuji Hotta

    2014-01-01

    Microwave processing has great potential for improving composite manufacturing such as reduction of curing time, energy requirements and operational costs. In this paper, the effects of microwave irradiation for resin-curing of carbon fiber/epoxy resin composite that was composed of discontinuous carbon fibers of 130 ?m or 3 mm were investigated. The mechanical properties of carbon fiber/epoxy resin composite cured by microwave irradiation for 20 min at 120°C were si...

  14. 21 CFR 175.380 - Xylene-formaldehyde resins condensed with 4,4?-isopropylidenediphenol-epichlorohydrin epoxy resins.

    Science.gov (United States)

    2010-04-01

    ...-isopropylidenediphenol-epichlorohydrin epoxy resins. 175.380 Section 175.380 Food and Drugs FOOD AND DRUG ADMINISTRATION... Xylene-formaldehyde resins condensed with 4,4?-isopropylidenediphenol-epichlorohydrin epoxy resins. The...?-isopropylidenediphenol-epichlorohydrin epoxy resins, to which may have been added certain optional adjuvant...

  15. Modified BET Equation for Determination of Micropore Pore Volume and Mesopore Surface Area in Microporous-Mesoporous Solids.

    Czech Academy of Sciences Publication Activity Database

    Šolcová, Olga; Mat?jová, Lenka; Hudec, P.; Schneider, Petr

    Cambridge : Royal Society of Chemistry Publishing, 2009 - (Kaskel, S.; Rodriguez-Reinoso, F.; Seaton, N.), s. 218-224 ISBN 978-1-84755-904-3. ISSN 0260-6291. [International Symposium on the Characterization of Porous Solids /8./. Edinburg (GB), 10.06.2008-13.06.2008] R&D Projects: GA AV ?R IAA4072404; GA AV ?R KAN400720701 Grant ostatní: GA VEGA(SK) 1/3575/06 Institutional research plan: CEZ:AV0Z40720504 Keywords : microporous-mesoporous solids * mesopore surface area * BET equation Subject RIV: CA - Inorganic Chemistry

  16. Hydraulic Permeability of Resorcinol-Formaldehyde Resin

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Paul Allen [ORNL

    2010-01-01

    An ion exchange process using spherical resorcinol-formaldehyde (RF) resin is the baseline process for removing cesium from the dissolved salt solution in the high-level waste tanks at the Hanford Site, using large scale columns as part of the Waste Treatment Plant (WTP). The RF resin is also being evaluated for use in the proposed small column ion exchange (SCIX) system, which is an alternative treatment option at Hanford and at the Savannah River Site (SRS). A recirculating test loop with a small ion exchange column was used to measure the effect of oxygen uptake and radiation exposure on the permeability of a packed bed of the RF resin. The lab-scale column was designed to be prototypic of the proposed Hanford columns at the WTP. Although the test equipment was designed to model the Hanford ion exchange columns, the data on changes in the hydraulic permeability of the resin will also be valuable for determining potential pressure drops through the proposed SCIX system. The superficial fluid velocity in the lab-scale test (3.4-5.7 cm/s) was much higher than is planned for the full-scale Hanford columns to generate the maximum pressure drop expected in those columns (9.7 psig). The frictional drag from this high velocity produced forces on the resin in the lab-scale tests that matched the design basis of the full-scale Hanford column. Any changes in the resin caused by the radiation exposure and oxygen uptake were monitored by measuring the pressure drop through the lab-scale column and the physical properties of the resin. Three hydraulic test runs were completed, the first using fresh RF resin at 25 C, the second using irradiated resin at 25 C, and the third using irradiated resin at 45 C. A Hanford AP-101 simulant solution was recirculated through a test column containing 500 mL of Na-form RF resin. Known amounts of oxygen were introduced into the primary recirculation loop by saturating measured volumes of the simulant solution with oxygen and reintroducing the oxygenated simulant into the feed tank. The dissolved oxygen (DO) concentration of the recirculating simulant was monitored, and the amount of oxygen that reacted with the resin was determined from the change in the DO concentration of the recirculating simulant solution. Prior to hydraulic testing the resin for runs 2 and 3 was covered with the simulant solution and irradiated in a spent fuel element at the Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR). Both batches of resin were irradiated to a total gamma dose of 177 Mrad, but the resin for run 2 reached a maximum temperature during irradiation of 51 C, while the resin for run 3 reached a temperature of 38 C. The different temperatures were the result of the operating status of HFIR at the time of the irradiation and were not part of the test plan; however, the results clearly show the impact of the higher-temperature exposure during irradiation. The flow rate and pressure drop data from the test loop runs show that irradiating the RF resin reduces both the void fraction and the permeability of the resin bed. The mechanism for the reduction in permeability is not clear because irradiation increases the particle size of the resin beads and makes them deform less under pressure. Microscopic examination of the resin beads shows that they are all smooth regular spheres and that irradiation or oxygen uptake did not change the shape of the beads. The resin reacts rapidly with DO in the simulant solution, and the reaction with oxygen reduces the permeability of a bed of new resin by about 10% but has less impact on the permeability of irradiated resin. Irradiation increases the toughness of the resin beads, probably by initiating cross-linking reactions in them. Oxygen uptake reduces the crush strength of both new and irradiated resin; however, the pressures that caused the beads to crush are much higher than would be expected during the operation of an ion exchange column. There was no visible evidence of broken beads in any of the resin samples taken from the test loop. Reaction with oxygen red

  17. Advanced cement solidification technique for spent resins

    International Nuclear Information System (INIS)

    In the past 40 years, the nuclear facilities of China Institute of Atomic Energy (CIAE) produced an amount of radioactive organic resins, a kind of problematic stream in nuclear industry. As these facilities were stepping into decommissioning, the treatment of the spent organic resins was put on the agenda. The various routes for spent resin treatment such as incineration, advanced oxidation, cement immobilization, etc, were considered. Each method has its advantages and disadvantages when applied in the treatment of spent resins. Since the quantities of the spent organic resins were relatively small and an experience with variety of cementation processes existed in CIAE, predominately for immobilization of the evaporated concentrates, the option of direct encapsulation of the spent organic resins into cementitious materials was adopted in 2003, as a preferred method from the point of view of saving the on the cost of the disposal. In order to realize the end goal, the main work consisted of: the survey of the source terms; cementitious material formula investigation; and the process development. This work, which was undertaken in the following years, is addressed as follows. Source terms of the spent resins in CIAE were to be made clear firstly. The results showed that a total of 24-29 m3 of spent resins was generated and accumulated in the past 40 years. Spent resin arose from two research reactors (heavy water reactor and light water reactor), and from the waste management plant. The amount of the spent resins from the heavy water reactor was 1m3 or so, but its radioactive concentration was high to ?108-?109Bq/m3. Two kinds of cements, ASC and OPC cement were selected next, as the solidifying matrix to be investigated. A mixture surface response approach was employed to design experiment and interpret data. In comparison, ASC was superior to OPC cement and it displayed preferable performances to encapsulate spent resins. The optimum formulation is:1) resin: .17(dry w/w); and 2) ASC cement: .43; zeolite: .10; water: .30. The properties of the resulting resin-cement concrete mix met the national criterion and the process requirements. These properties included 104mm for the slump, 9.6(Mpa) for the 28-day compressive strength, 1.2% and 6.0% for the compressive strength loss after 42-day water immersion and 5 thaw-freeze circles, 2.72E-06(cm2/d) and 1.63E-07 (cm2/d) for 137Cs and 60Co diffusivities. Lastly, a scale-up demonstration of 200L and the corresponding process was carried out. The cementation process was performed in batches directly in the final storage container, which was a 200L steel drum. Based on the recommended concrete formulation and on the determined operation conditions, the large volumes of resin-cement concretes were produced. The properties of the resin-cement concretes were examined by analysis of drilling cores. The results showed that homogeneous solidified forms were obtained under the given process parameters, and that mechanical performances and the peak temperature satisfied the regulatory requirements. The source term investigation provided the basis for determination of the status of radioactive ion-exchange resins in CIAE. The cement formula as well as the cold bench scale test reached the required end goal, which established bases for the active pilot process, although some improvement should be done in the future. (author)

  18. Synthesis of improved phenolic and polyester resins

    Science.gov (United States)

    Delano, C. B.

    1980-01-01

    Thirty-seven cured phenolic resin compositions were prepared and tested for their ability to provide improved char residues and moisture resistance over state of the art epoxy resin composite matrices. Cyanate, epoxy novolac and vinyl ester resins were investigated. Char promoter additives were found to increase the anaerobic char yield at 800 C of epoxy novolacs and vinyl esters. Moisture resistant cyanate and vinyl ester compositions were investigated as composite matrices with Thornel 300 graphite fiber. A cyanate composite matrix provided state of the art composite mechanical properties before and after humidity exposure and an anaerobic char yield of 46 percent at 800 C. The outstanding moisture resistance of the matrix was not completely realized in the composite. Vinyl ester resins showed promise as candidates for improved composite matrix systems.

  19. Amine chemistry. Update on impact on resin

    Energy Technology Data Exchange (ETDEWEB)

    Bachman, Gregory; Kellogg, Douglas [Siemens Industry, Inc., Rockford, IL (United States). Technology and Lab Services; Wilkes, Marty [Siemens Industry, Inc., Rockford, IL (United States). Water Technologies Div.

    2012-03-15

    Impurity removal in the steam cycle and the associated prevention of corrosion and/or fouling of system components are the goals of ion exchange resins. However, in many instances (such as a switch to amine chemistry or a change in product specifications), resins do not remove, and, in fact, contribute impurities to the steam cycle. This paper reviews recent data compiled to determine the direct and indirect effects of amines on ion exchange resins used in the power industry. Water chemistries have improved in recent years, in large part due to changes in chemistry and resins, but it is necessary to continue to develop products, processes and techniques to reduce impurities and improve overall water chemistry in power plant systems. (orig.)

  20. Adsorption of plant phenols by polystyrene resins

    OpenAIRE

    Akiyoshi Fukushima; Hioaki Hase; Koshi Saito

    1987-01-01

    Adsorption of nine plant phenols by nine polystyrene ion-exchange resins was investigated in an experimental model system. The phenols were adsorbed by Amberlite CG-120 more efficiently than any other acidically charged resins tested in this study. They were also taken up by anion exchangers. Among them Dowex 1-X8 was found to show the strongest effect on the adsorption of the phenolic constituents applied. A comparison of the efficiency of plant phenol adsorption between two different types ...

  1. Cesium-specific phenolic ion exchange resin

    Science.gov (United States)

    Bibler, Jane P. (Aiken, SC); Wallace, Richard M. (Aiken, SC)

    1995-01-01

    A phenolic, cesium-specific, cation exchange resin is prepared by neutralizing resorcinol with potassium hydroxide, condensing/polymerizing the resulting intermediate with formaldehyde, heat-curing the resulting polymer to effect cross-linking and grinding it to desired particle size for use. This resin will selectively and efficiently adsorb cesium ions in the presence of a high concentration of sodium ions with a low carbon to cesium ratio.

  2. Eluting uranium from ion-exchange resins

    International Nuclear Information System (INIS)

    A method is claimed for recovering uranium and/or related values from an ion-exchange resin. The values are desorbed from the resin by an eluant, and precipitated from the eluate by the addition of hydrogen peroxide. The decant solution is used to make up fresh eluant for recycling. It is passed through a catalytic material capable of decomposing any hydrogen peroxide present in the solution

  3. Clinical applications of preheated hybrid resin composite.

    Science.gov (United States)

    Rickman, L J; Padipatvuthikul, P; Chee, B

    2011-07-01

    This clinical article describes and discusses the use of preheated nanohybrid resin composite for the placement of direct restorations and luting of porcelain laminate veneers. Two clinical cases are presented. Preheating hybrid composite decreases its viscosity and film thickness offering the clinician improved handling. Preheating also facilitates the use of nanohybrid composite as a veneer luting material with relatively low polymerisation shrinkage and coefficient of thermal expansion compared to currently available resin luting cements. PMID:21779058

  4. Cycloaliphatic epoxide resins for cationic UV - cure

    International Nuclear Information System (INIS)

    This paper introduces the cyclo - aliphatic epoxide resins used for the various applications of radiation curing and their comparison with acrylate chemistry. Radiation curable coatings and inks are pre - dominantly based on acrylate chemistry but over the last few years, cationic chemistry has emerged successfully with the unique properties inherent with cyclo - aliphatic epoxide ring structures. Wide variety of cationic resins and diluents, the formulation techniques to achieve the desired properties greatly contributes to the advancement of UV - curing technology

  5. 21 CFR 177.1500 - Nylon resins.

    Science.gov (United States)

    2010-04-01

    .... Nylon 6/69 resins for use only as specified in 21 CFR 177.1395 of this chapter 1.09±0.02 270-277 >140..., see the List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Nylon resins. 177.1500 Section 177.1500 Food...

  6. Biocompatibility of Resin-based Dental Materials

    OpenAIRE

    Keyvan Moharamzadeh; Brook, Ian M.; Richard van Noort

    2009-01-01

    Oral and mucosal adverse reactions to resin-based dental materials have been reported. Numerous studies have examined thebiocompatibility of restorative dental materials and their components, and a wide range of test systems for the evaluation of the biological effects of these materials have been developed. This article reviews the biological aspects of resin-based dental materials and discusses the conventional as well as the new techniques used for biocompatibility assessment of dental mat...

  7. Core/shell magnetic mesoporous silica nanoparticles with radially oriented wide mesopores

    Directory of Open Access Journals (Sweden)

    Nikola Ž. Kneževi?

    2014-06-01

    Full Text Available Core/shell nanoparticles, containing magnetic iron-oxide (maghemite core and mesoporous shell with radial porous structure, were prepared by dispersing magnetite nanoparticles and adding tetraethylorthosilicate to a basic aqueous solution containing structure-templating cetyltrimethylammonium bromide and a pore-swelling mesithylene. The material is characterized by SEM and TEM imaging, nitrogen sorption and powder X-ray di?raction. Distinctive features of the prepared material are its high surface area (959 m2/g, wide average pore diameter (12.4 nm and large pore volume (2.3 cm3/g. The material exhibits radial pore structure and the high angle XRD pattern characteristic for maghemite nanoparticles, which are obtained upon calcination of the magnetite-containing material. The observed properties of the prepared material may render the material applicable in separation, drug delivery, sensing and heterogeneous catalysis.

  8. Correct Determination of Textural Properties in Microporous-Mesoporous Solids.

    Czech Academy of Sciences Publication Activity Database

    Šolcová, Olga; Šnajdaufová, Hana; Mat?jová, Lenka

    2010, s. 26. ISBN N. [International Conference on Pure and Applied Chemistry (ICPAC-2010). Mauritius (MU), 26.07.2010-30.07.2010] R&D Projects: GA AV ?R KAN400720701; GA ?R GA104/09/0694 Institutional research plan: CEZ:AV0Z40720504 Keywords : texture * micro-mesoporous solids * physisorption Subject RIV: CF - Physical ; Theoretical Chemistry

  9. High-Resolution Adsorption of Nitrogen on Mesoporous Alumina.

    Czech Academy of Sciences Publication Activity Database

    ?ejka, Ji?í; Žilková, Nad?žda; Rathouský, Ji?í; Zukal, Arnošt

    2004-01-01

    Ro?. 20, - (2004), s. 7532-7539. ISSN 0743-7463 R&D Projects: GA AV ?R IAA4040411; GA ?R GA104/02/0571 Grant ostatní: NATO(XE) SfP974 217 Institutional research plan: CEZ:AV0Z4040901 Keywords : nitrogen * mesoporous alumina * adsorption Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.295, year: 2004

  10. Mesoporous molecular sieves - advanced supports for olefin metathesis catalyst.

    Czech Academy of Sciences Publication Activity Database

    Balcar, Hynek; ?ejka, Ji?í

    Leipzig : Leibnitz-Institut für Oberflächenmodifizierung (IOM), 2009. O 18-O 18. [The International Symposium on Olefin Metathesis and Related CHemistry /18./. 02.08.2009-07.08.2009, Leipzig] Institutional research plan: CEZ:AV0Z40400503 Keywords : mesoporous molecular sieves * olefin metathesis catalyst * molybdenum Subject RIV: CF - Physical ; Theoretical Chemistry

  11. Mesoporous molecular sieves as supports for metathesis catalysts.

    Czech Academy of Sciences Publication Activity Database

    Balcar, Hynek; ?ejka, Ji?í

    Dordrecht : Springer, 2007, s. 151-166. ISBN 978-1-4020-6090-8 R&D Projects: GA AV ?R IAA4040411; GA ?R GA203/05/2194 Institutional research plan: CEZ:AV0Z40400503 Keywords : mesoporous molecular sieves * heterogeneous catalysts * olefin metathesis * metathesis polymerization Subject RIV: CF - Physical ; Theoretical Chemistry

  12. Solution Plasma Process for Template Removal in Mesoporous Silica Synthesis

    Science.gov (United States)

    Pootawang, Panuphong; Saito, Nagahiro; Takai, Osamu

    2010-12-01

    The plasma discharge in aqueous solution was scientifically studied and applied to template removal in mesoporous silica synthesis. Highly dispersed spherical mesoporous silica particles were synthesized by the ternary surfactant system containing the Pluronic P123 copolymer (EO20PO69EO20), sodium dodecylbenzene sulfonate, and 1,1,2,2,3,3,4,4,4-nonafluoro-1-butane sulfonate, via the sol-gel method in acid solutions. The solution plasma process (SPP), instead of conventional thermal calcinations, was used to remove the template. The mechanism of the removal of the organic template occurred via oxidation by the hydroxyl radicals generated during discharge. The transformation of a mesopore structure from a disordered wormlike structure to a hexagonally arranged structure was observed by X-ray diffraction analysis and was confirmed by transmission electron microscopy. The results of the thermal analysis and functional group identification of mesoporous silica after SPP showed evidence of organic template removal. The surface area calculated using the Brunauer-Emmett-Teller (BET) theory and the mean pore diameter results could be used to evaluate the plasma efficiency, demonstrating that this method does not affect the pore size in the case of discharge in a solution of pH 3 compared with the results of thermal calcination. Hence, SPP was proved to be highly efficient for organic template removal, exhibiting short consumption time and less contamination.

  13. Mesoporous molecular sieves immobilized Ru catalysts for olefin metathesis.

    Czech Academy of Sciences Publication Activity Database

    Balcar, Hynek; Bek, David; Žilková, Nad?žda

    Stockholm : Stockholm University, 2009 - (Bäckvall, J.). P-8 [International Symposium on Relations between Homogeneous and Heterogeneous Catalysis /14./. 13.09.2009-18.09.2009, Stockholm ] Institutional research plan: CEZ:AV0Z40400503 Keywords : Ru catalysts * mesoporous molecular sieves * olefin metathesis Subject RIV: CF - Physical ; Theoretical Chemistry

  14. Aromatic Transformations Over Mesoporous ZSM-5: Advantages and Disadvantages.

    Czech Academy of Sciences Publication Activity Database

    Musilová, Zuzana; Žilková, Nad?žda; Park, S.-E.; ?ejka, Ji?í

    2010-01-01

    Ro?. 53, 19-20 (2010), s. 1457-1469. ISSN 1022-5528 Institutional research plan: CEZ:AV0Z40400503 Keywords : mesoporous ZSM-5 * alkylation * disproportionation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.359, year: 2010

  15. Pore ordering in mesoporous matrices induced by different directing agents.

    Czech Academy of Sciences Publication Activity Database

    Putz, A.-M.; Cecilia, S.; Ianasi, C.; Dudás, Z.; Székely, N. K.; Plocek, Ji?í; Sfarloaga, P.; Sacarescu, L.; Almásy, L.

    2015-01-01

    Ro?. 22, ?. 2 (2015), s. 321-331. ISSN 1380-2224 Institutional support: RVO:61388980 Keywords : Mesoporous silica * MCM-41 * Dodecyl-trimethyl ammonium bromide * Hexadecyl-trimethylammonium bromide Subject RIV: CA - Inorganic Chemistry Impact factor: 1.108, year: 2014

  16. Mesoporous molecular sieves as advanced supports for olefin metathesis catalysts.

    Czech Academy of Sciences Publication Activity Database

    Balcar, Hynek; ?ejka, Ji?í

    2013-01-01

    Ro?. 257, 21-22 (2013), s. 3107-3124. ISSN 0010-8545 R&D Projects: GA AV ?R IAA400400805; GA ?R GBP106/12/G015 Institutional support: RVO:61388955 Keywords : Olefin metathesis * mesoporous molecular sieves * Heterogeneous catalysts Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 12.098, year: 2013

  17. Novel Mesoporous Polydivinylbenzenes with Very High Surface Area.

    Czech Academy of Sciences Publication Activity Database

    Je?ábek, Karel

    - : American Chemical Society, 2013, s. 1. ISBN N. [245th ACS National Meeting and Exposition. New Orleans, LA (US), 07.04.2013-11.04.2013] R&D Projects: GA MŠk LH12194 Institutional support: RVO:67985858 Keywords : mesoporous * polydivinylbenzene * surface area Subject RIV: CF - Physical ; Theoretical Chemistry

  18. Mesoporous Molecular Sieves as Advanced Supports for Olefin Metathesis Catalysts.

    Czech Academy of Sciences Publication Activity Database

    Balcar, Hynek; ?ejka, Ji?í

    2010-01-01

    Ro?. 293, ?. 1 (2010), s. 43-47. ISSN 1022-1360 R&D Projects: GA AV ?R IAA400400805; GA AV ?R KAN100400701 Institutional research plan: CEZ:AV0Z40400503 Keywords : heterogeneous catalysts * mesoporous molecular sieves * olefin metathesis Subject RIV: CF - Physical ; Theoretical Chemistry

  19. Alkylation and Disproportionation of Aromatic Hydrocarbons over Mesoporous Molecular Sieves.

    Czech Academy of Sciences Publication Activity Database

    ?ejka, Ji?í; Krej?í, Andrea; Žilková, Nad?žda; D?de?ek, Ji?í; Hanika, J.

    44-45, 1/3 (2001), s. 499-507. ISSN 1387-1811 R&D Projects: GA AV ?R IAA4040001 Institutional research plan: CEZ:AV0Z4040901 Keywords : mesoporous MCM-41 * heteropoly acids * aromatic hydrocarbons Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.497, year: 2001

  20. Cleanup of TMI-2 demineralizer resins

    International Nuclear Information System (INIS)

    Radiocesium is being removed from Demineralizers A and B (DA and DB by a process that was developed from laboratory tests on small samples of resin from the demineralizers. The process was designed to elute the radiocesium from the demineralizer resins and then to resorb it onto the zeolite ion exchangers contained in the Submerged Demineralizer System (SDS). The process was also required to limit the maximum cesium activities in the resin eluates (SDS feeds) so that the radiation field surrounding the pipelines would not be excessive. The process consists of 17 stages of batch elution. In the initial stage, the resin is contacted with 0.18 M boric acid. Subsequent stages subject the resin to increasing concentrations of sodium in NaH2BO3-H3BO3 solution (total B = 0.35 M) and then 1 M sodium hydroxide in the final stages. Results on the performance of the process in the cleanup of the demineralizers at TMI-2 are compared to those obtained from laboratory tests with small samples of the DA and DB resins. To date, 15 stages of batch elution have been completed on the demineralizers at TMI-2 which resulted in the removal of about 750 Ci of radiocesium from DA and about 3300 Ci from DB

  1. Electrosynthesis of Epoxy Resins via Superoxide Anion

    Directory of Open Access Journals (Sweden)

    Rajni Mathur

    2013-04-01

    Full Text Available Epoxy resins are a class of reactive pre polymers and polymers which contain epoxide groups. Inspite of their high costs the epoxy resins find many important applications. The resins are used in both molding and laminating technique for making glass fiber-reinforced articles which are having better mechanical strength chemical resistance and electrical insulating properties. They also use in casting, potting encapsulating and embedment in the electrical and tooling industries. The general important uses are industrial flooring adhesive foams, highway surfacing patching material and stabilizers for vinyl resins. Epoxy resins may be reacted either with them- selves through catalytic homo polymerization or with a wide range of co-reactant like amino acid ,phenol, alcohols and thiols. These co-reactants are referred to as curatives. When linear epoxy resins react with suitable curative to form three dimensional cross linked thermo state structure. Epoxidation of unsaturated alcohol is carried out with the help of superoxide. The electrochemical generation of super-oxide anion and subsequent electro oxidation in situ is found to be advantageous and easy over the conventional technique. The work extended further in persuasive oxygen reduction studies on non-metallic surface such as different types of carbon and graphite with a view to understand the reaction mechanism and possible application to fuel cell technology.

  2. Synthesis of mesoporous zeolite single crystals with cheap porogens

    International Nuclear Information System (INIS)

    Mesoporous zeolite (silicalite-1, ZSM-5, TS-1) single crystals have been successfully synthesized by adding soluble starch or sodium carboxymethyl cellulose (CMC) to a conventional zeolite synthesis system. The obtained samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen sorption analysis, 27Al magic angle spinning nuclear magnetic resonance (27Al MAS NMR), temperature-programmed desorption of ammonia (NH3-TPD) and ultraviolet-visible spectroscopy (UV-vis). The SEM images clearly show that all zeolite crystals possess the similar morphology with particle size of about 300 nm, the TEM images reveal that irregular intracrystal pores are randomly distributed in the whole crystal. 27Al MAS NMR spectra indicate that nearly all of the Al atoms are in tetrahedral co-ordination in ZSM-5, UV-vis spectra confirm that nearly all of titanium atoms are incorporated into the framework of TS-1. The catalytic activity of meso-ZSM-5 in acetalization of cyclohexanone and meso-TS-1 in hydroxylation of phenol was also studied. The synthesis method reported in this paper is cost-effective and environmental friendly, can be easily expended to prepare other hierarchical structured zeolites. - Graphical abstract: Mesoporous zeolite single crystals were synthesized by using cheap porogens as template. Highlights: ? Mesoporous zeolite (silicalite-1, ZSM-5, TS-1) single crystals were synthesized. ? Soluble starch or sodium carboxymethyl cellulose (CMC) was used as porogens. ? The mesoporous zeolites had connected mesopores although closed pores existed. ? Higher catalytic activities were obtained.

  3. Synthesis, characterization and catalytic activity of a novel mesoporous ZSM-5 zeolite

    International Nuclear Information System (INIS)

    Highlights: ? Mesoporous ZSM-5 zeolites. ? The strong acidic intensity. ? High activity for the alkylation of phenol and tert-butyl alcohol. ? Remarkable hydrothermal stability. - Abstract: A novel mesoporous ZSM-5 zeolite was hydrothermally synthesized using glucose as a template. Characterizations by XRD, TEM and nitrogen isotherms indicated that ZSM-5 possessed worm-like mesoporous. 27Al-MAS-NMR and NH3-TPD showed that the mesoporous ZSM-5 preserved tetrahedral coordination aluminum and stronger acidity than conventional mesoporous material. As-prepared mesoporous ZSM-5 was successfully used in alkylation reaction of phenol with tert-butanol and exhibited significantly high phenol conversion and 2,4-DTBP selectivity. In addition, the hydrothermal stability was also studied by boiling in water for 7 days and displayed good results

  4. Synthesis, characterization and catalytic activity of a novel mesoporous ZSM-5 zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Yuanyuan [College of Chemistry, Jilin University, Changchun 130023 (China); Key Laboratory of Fine Chemicals of College of Heilongjiang Province, Qiqihar University, Qiqihar 161006 (China); Hu, Jing [College of Chemistry, Jilin University, Changchun 130023 (China); Jia, Lihua [Key Laboratory of Fine Chemicals of College of Heilongjiang Province, Qiqihar University, Qiqihar 161006 (China); Li, Zhifang [College of Chemistry, Jilin University, Changchun 130023 (China); Kan, Qiubin, E-mail: catalysischina@yahoo.com.cn [College of Chemistry, Jilin University, Changchun 130023 (China); Wu, Shujie, E-mail: wusj@jlu.edu.cn [College of Chemistry, Jilin University, Changchun 130023 (China)

    2013-05-15

    Highlights: ? Mesoporous ZSM-5 zeolites. ? The strong acidic intensity. ? High activity for the alkylation of phenol and tert-butyl alcohol. ? Remarkable hydrothermal stability. - Abstract: A novel mesoporous ZSM-5 zeolite was hydrothermally synthesized using glucose as a template. Characterizations by XRD, TEM and nitrogen isotherms indicated that ZSM-5 possessed worm-like mesoporous. {sup 27}Al-MAS-NMR and NH{sub 3}-TPD showed that the mesoporous ZSM-5 preserved tetrahedral coordination aluminum and stronger acidity than conventional mesoporous material. As-prepared mesoporous ZSM-5 was successfully used in alkylation reaction of phenol with tert-butanol and exhibited significantly high phenol conversion and 2,4-DTBP selectivity. In addition, the hydrothermal stability was also studied by boiling in water for 7 days and displayed good results.

  5. The benefits of meso-porous solids for the nuclear industry

    International Nuclear Information System (INIS)

    A meso-porous material is a porous material whose pores have a width between 2 nm and 50 nm. In the early nineties, new synthesis methods were discovered, providing ways of obtaining meso-porous ceramics in large quantities.These scientific advances thus made it possible to bring in meso-porous systems in many fields of research, e.g. catalysis, gas detection, water decontamination. Somewhat surprisingly, the nuclear world stood relatively aloof from this veritable vogue, even though the properties exhibited by meso-porous solids turn out to be highly attractive. Meso-porous materials appears to be choice materials in separation chemistry, actinide extraction, retention of radionuclides, decontamination of radioactive effluents, and even in reducing the impact of heavy irradiations. The combination of meso-porous materials with nano-structured materials opens a broad field of investigation concerning all the materials used in the nuclear sector and particularly in the fuel cycle. (A.C.)

  6. Multitasking mesoporous nanomaterials for biorefinery applications

    Energy Technology Data Exchange (ETDEWEB)

    Kandel, Kapil [Ames Laboratory

    2013-05-02

    Mesoporous silica nanoparticles (MSNs) have attracted great interest for last two decades due to their unique and advantageous structural properties, such as high surface area, pore volume, stable mesostructure, tunable pore size and controllable particle morphology. The robust silica framework provides sites for organic modifications, making MSNs ideal platforms for adsorbents and supported organocatalysts. In addition, the pores of MSNs provide cavities/ channels for incorporation of metal and metal oxide nanoparticle catalysts. These supported metal nanoparticle catalysts benefit from confined local environments to enhance their activity and selectivity for various reactions. Biomass is considered as a sustainable feedstock with potential to replace diminishing fossil fuels for the production of biofuels. Among several strategies, one of the promising methods of biofuel production from biomass is to reduce the oxygen content of the feedstock in order to improve the energy density. This can be achieved by creating C-C bonds between biomass derived intermediates to increase the molecular weight of the final hydrocarbon molecules. In this context, pore size and organic functionality of MSNs are varied to obtain the ideal catalyst for a C-C bond forming reaction: the aldol condensation. The mechanistic aspects of this reaction in supported heterogeneous catalysts are explored. The modification of supported organocatalyst and the effect of solvent on the reaction are rationalized. The significance of two functional surfaces of MSNs is exploited by enzyme immobilization on the external surface and organo catalyst functionalization on the internal surface. Using this bifunctional catalyst, the tandem conversion of small chain alcohols into longer chain hydrocarbon molecules is demonstrated. The ability to incorporate metal and metal oxide nanoparticles in the pores and subsequent functionalization led to develop organic modified magnetic MSNs (OM-MSNs) for applications in microalgae biorefinery. Two different integrated biorefinery systems are highlighted. (i) OM-MSNs are used to harvest microalgae and selectively sequester free fatty acids (FFAs). (ii) OM-MSNs are shown to selectively sequester FFAs and convert them into diesel-range liquid hydrocarbon fuels. A similar MSN supported metal nanoparticle catalyst is demonstrated to transform FFAs into green diesel with even greater activity and selectivity. The incorporation of a different organic functional group into MSN provides a selective adsorbent for separation and purification of ?-tocopherol from microalgae oil. The functional group with electron deficient aromatic rings demonstrated high sequestration capacity and selectivity of {alpha}-tocopherol.

  7. A study of asphaltene-resin interactions

    Scientific Electronic Library Online (English)

    Luiz C. C., Marques; Juliana O., Pereira; André D., Bueno; Valdo S., Marques; Elizabete F., Lucas; Claudia R. E., Mansur; André L. C., Machado; Gaspar, González.

    2012-10-01

    Full Text Available Foi realizado um estudo para investigar a interação entre asfaltenos (em soluções de tolueno) e resinas (em soluções de n-heptano). Para entender melhor o tipo de interação entre essas frações, quantificou-se o consumo de resina quando asfaltenos (dissolvidos em tolueno) foram precipitados com uma s [...] olução de n-heptano contendo resina. Os resultados indicaram que a precipitação de asfaltenos ocorre juntamente com a redução na concentração de resina. Os perfis das isotermas de ligação indicaram que a saturação ocorreu em um caso, em quanto que o efeito cooperativo com posterior platô inicial foi observado para duas outras amostras. Estes resultados confirmaram a hipótese de que resinas podem adsorver em asfaltenos, mas não podem evitar floculação e precipitação de asfaltenos. Além disso, resultados de microcalorimetria sugeriram que a resina e asfalteno interagem por forças fracas de van der Waals. Estes resultados estão em contraste com a escola de pensamento predominante desde a década de 1940 que advoga que as resinas podem peptizar e estabilizar asfaltenos. Abstract in english A study was carried out to investigate the interaction between asphaltenes (in toluene solutions) and resins (in n-heptane solutions). To better understand the type of interaction between these fractions, it was quantified the resin uptake when asphaltenes (dissolved in toluene) were precipitated by [...] a resin-containing n-heptane solution. These results indicated the asphaltene precipitation occurs together with a reduction in the resin concentration. The binding isotherm profiles indicated that saturation occurred in one case, while collective association following an initial plateau was observed for the other two samples. These results confirmed the hypothesis that resins can adsorb on asphaltenes but cannot prevent asphaltenes from flocculating and precipitating. Furthermore, microcalorimetric results suggested that the resin and asphaltene interact by weak van der Waals forces. These results are in stark contrast with the school of thought prevalent since the 1940s that resins can peptize and stabilize asphaltenes.

  8. USE OF BABAÇU FLOUR WITH ALTERNATIVE EXTENDER FOR PLYWOOD MANUFACTURING

    Directory of Open Access Journals (Sweden)

    Érika da Silva Ferreira

    2009-10-01

    Full Text Available This work aims at evaluating the potentiality of babaçu flour under differents percents (0%, 50%, 75%, and 100% as alternative extensers to wheatmeal for plywood manufacturing. Third three panels with five veneers were produced using Araucaria angustifolia (Bert. Ktze, with urea-formaldehyde – UF and phenol-formaldehyde – FF resins and being three panels per treatment. The following formulations (in parts per wheight were used: UF resin – 100 x extender – 50 x water – 50 x catalyst – 7 and FF resin – 100 x extender – 18 x water – 22. The results of both glue line shear strength obtained for plywood manufactured with urea-formaldehyde and phenol-formaldehyde resins showed the feasibility of the use of babaçu flour as the extender in parcial or total substitution of wheat flour in the plywood manufactures.

  9. Mesoporous zeolite single crystal catalysts: Diffusion and catalysis in hierarchical zeolites

    DEFF Research Database (Denmark)

    Christensen, Christina Hviid; Johannsen, Kim; Toernqvist, Eric; Schmidt, Iver; Topsoe, Henrik; Christensen, Claus H.

    2007-01-01

    During the last years, several new routes to produce zeolites with controlled mesoporosity have appeared. Moreover, an improved catalytic performance of the resulting mesoporous zeolites over conventional zeolites has been demonstrated in several reactions. In most cases, the mesoporous zeolites exhibit higher catalytic activity, but in some cases also improved selectivity and longer catalyst lifetime has been reported. The beneficial effects of introducing mesopores into the zeolites has in mos...

  10. Hierarchical zeolites: progress on synthesis and characterization of mesoporous zeolite single crystal catalysts

    DEFF Research Database (Denmark)

    Kustova, Marina; Egeblad, Kresten; Christensen, Claus H.; Kustov, Arkadii; Christensen, Christina Hviid

    2007-01-01

    Recently, a new family of crystalline zeolitic materials was reported, the so-called mesoporous zeolite single crystals featuring individual zeolite single crystals with an additional noncrystalline mesopore system interconnected with the usual micropore system of the zeolite, resulting in a hierarchical pore size distribution. In this work, the preparation of mesoporous ZSM-12 single crystal catalysts using a new improved procedure for directly introducing carbon in the reaction mixture is repo...

  11. Multifunctional hybrid nanocarrier: Magnetic CNTs ensheathed with mesoporous silica for drug delivery and imaging system

    OpenAIRE

    R. K. Singh; K. D. Patel; Kim, J-J; Kim, T-H.; Kim, J-H; Shin, U. S.; Lee, E-J; Kim, H-W; Knowles, J. C.

    2014-01-01

    Here we communicate the development of a novel multifunctional hybrid nanomaterial, magnetic carbon nanotubes (CNTs) ensheathed with mesoporous silica, for the simultaneous applications of drug delivery and imaging. Magnetic nanoparticles (MNPs) were first decorated onto the multiwalled CNTs, which was then layered with mesoporous silica (mSiO) to facilitate the loading of bioactive molecules to a large quantity while exerting magnetic properties. The hybrid nanomaterial showed a high mesopor...

  12. Photon-Manipulated Drug Release from Mesoporous Nanocontainer Controlled by Azobenzene-Modified Nucleic Acid

    OpenAIRE

    YUAN, QUAN; ZHANG, YUNFEI; CHEN, TAO; Lu, Danqing; Zhao, Zilong; Zhang, Xiaobing; Li, Zhenxing; Yan, Chun-Hua; Tan, Weihong

    2012-01-01

    Herein a photon manipulated mesoporous release system was constructed based on azobenzene-modified nucleic acids. In this system, the azobenzene-incorporated DNA double strands were immobilized at the pore mouth of meso-porous silica nanoparticles. The photo-isomerization of azobenzene induced dehybridization/hybridization switch of complementary DNA, causing uncapping/capping of pore gates of mesoporous silica. This nanoplatform permits holding of guest molecules within the nanopores under v...

  13. CuO nanoparticles encapsulated inside Al-MCM-41 mesoporous materials via direct synthetic route

    OpenAIRE

    Chengli Huo; Jing Ouyang; Huaming Yang

    2014-01-01

    Highly ordered aluminum-containing mesoporous silica (Al-MCM-41) was prepared using attapulgite clay mineral as a Si and Al source. Mesoporous complexes embedded with CuO nanoparticles were subsequently prepared using various copper sources and different copper loadings in a direct synthetic route. The resulting CuO/Al-MCM-41 composite possessed p6mm hexagonally symmetry, well-developed mesoporosity, and relatively high BET surface area. In comparison to pure silica, these mesoporous material...

  14. Synthesis of novel Mesoporous Fullerene and its application to electro-oxidation of methanol

    OpenAIRE

    Mondal, Sujit K.

    2010-01-01

    One pot synthetic technique was used to synthesize mesoporous fullerene using highly ordered mesoporous template such as KIT6-150 and SBA-15-150. Highly ordered porous fullerene with cross linkage between the fullerene molecules was obtained at high temperature 900 0C. This type of highly ordered and high surface area mesoporous fullerence was used as catalyst to study anodic performance in sulphuric acid medium. Finally, it was used to test its catalytic activity for electr...

  15. Discussion on spent fuel bay purification resin selection

    International Nuclear Information System (INIS)

    The performance of spent fuel bay (SFB) clean up system is important for both radiation and radwaste reduction. Demineralizer resin is operated adverse conditions facing high levels of hydrogen peroxide generated from radiolysis of water and also direct radiation attack from radioactive colloids in the pool. Resin cross-linked structure will be easily destroyed, because of sulfate ion and purification efficiency rise and decline. This paper, through nuclear resin oxidation stability tests and based on the nuclear power plant application experience, discusses the failure mechanism of resin, and give the purification resin selection principle, in order to improve the purification efficiency and reduce the amount of radioactive spent resin. (authors)

  16. Preparation of superhydrophilic mesoporous SiO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Chen Peiyi [Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, College of Environmental Science and Engineering, South China University of Technology, Guangzhou 510006 (China); Hu Yun, E-mail: huyun@scut.edu.cn [Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, College of Environmental Science and Engineering, South China University of Technology, Guangzhou 510006 (China); Wei Chaohai [Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, College of Environmental Science and Engineering, South China University of Technology, Guangzhou 510006 (China)

    2012-03-01

    Using a simple sol-gel/spin-coating method, mesoporous SiO{sub 2} thin films were prepared on glass slides. All of the prepared thin films were colorless and transparent as original glass substrates. XRD and TEM measurements revealed that the prepared SiO{sub 2} thin films coated 3-12 times possess hexagonal mesoporous structure. The mesoporous SiO{sub 2} thin films performed the superhydrophilicity and antifogging property in the absence of UV light irradiation. The results suggested that the appropriate film thickness and mesoporous structures can improve the surface superhydrophilic behavior of SiO{sub 2} thin films.

  17. Morphological Control of Multifunctional Mesoporous Silica Nanomaterials for Catalysis Applications

    Energy Technology Data Exchange (ETDEWEB)

    Seong Huh

    2004-12-19

    I found an efficient method to control the morphology of the organically monofunctionalized mesoporous silica materials by introducing different types of organoalkoxysilanes in a base-catalyzed co-condensation reaction. The monofunctionalized materials exhibit different particle morphologies relative to the pure MCM-41 material. The concentration dependence of the morphology is a critical factor to determine the final particle shape. A proposed mechanism of the shape evolution is also offered. After understanding the role of organoalkoxysilanes in producing various well-shaped nanomaterials, I also obtained a series of bifunctional mesoporous silica materials with certain particle morphology. A series of bifunctional mesoporous silica nanospheres (MSNs) whose physicochemical properties was investigated via solid state NMR techniques and Cu{sup 2+} adsorption capacity tests, The ratio of two different organic groups inside of mesopores of these MSNs could be fine-tuned. These MSNs serve as a useful model system to study substrate selectivity in catalytic reactions and sorption phenomena. For example, the Cu{sup 2+} adsorption capacity of these materials was dictated by the chemical nature of the mesopores generated by the different organic functional groups. An investigation of the substrate selectivity of the bifunctionalized MSNs in a competitive nitroaldol reaction using an equimolar amount of two competing 4-nitrobenzaldehyde derivatives was performed. Shape-controlled bifunctional MSNs were employed as the catalysts. The properties of the MSNs were investigated using various spectroscopic methods and electron microscopy. The more hydrophobic the surface organic groups are, the higher the ratio of hydrophobic final product. This is the first example to demonstrate the selection of substrate using physicochemical nature of the mesopore surface other than the conventional shape selection in zeolite systems. I also created a cooperative dual catalyst system that is capable of activating two different substrates in aldol reaction, Henry reaction and cyanosilylation. One catalytic group activates the nucleophile, another organic group simultaneously activates the electrophile to enhance the total reaction rate. I systematically vaned the amount of two organic groups and performed the three model reactions to compare rate enhancements.

  18. Method of decomposing ion exchange resin wastes

    International Nuclear Information System (INIS)

    Purpose: To attain the shortening for the processing time, economization for the amount of chemical consumed and reduction in the size of the device upon decomposing treatment of radioactive ion exchange resins wastes by using oxidizers. Method: A reaction vessel for conducting pulverization and conversion into inorganic substances as the decomposing step for resin wastes is made of corrosion resistant and non-magnetic material and a great amount of spindle-like actuation pieces made of ferromagnetic material are contained in the vessel. Resin wastes and oxidizers (hydrogen peroxide), and decomposing catalyst (iron ions) are supplied to the vessel. When electric power is supplied to a moving type magnetic field generator disposed on both sides of the vessel, moving magnetic fields act to the inside of the vessel thereby causing each of the actuation pieces to float upwardly, rotate around its axis and revolve around the vessel. Thus, the resin wastes are pulverized into almost colloidal state, mixed sufficiently and reacted with chemicals and decomposed into inorganic materials. According to the result of the experiment, about 100 % of the resin wastes can be converted into inorganic material for about 4 minutes. (Kamimura, M.)

  19. Color stability of composite resin cements.

    Science.gov (United States)

    Smith, Darrell S; Vandewalle, Kraig S; Whisler, Gerry

    2011-01-01

    This study sought to determine the difference in color stability of resin cements after one year of storage in water. Three commercial resin cements (Nexus 3, Calibra, Variolink 2) were evaluated under three different curing conditions (photo-, dual-, and self-cure) over three storage time periods (3, 6, and 12 months). A plastic mold was used to prepare cylindrical specimens of each of the three resin cements. For the phototcured specimens, only the base component of the resin cement was cured. For the dual- and self-cure specimens, the base and catalyst of the cements were mixed according to the manufacturer's instructions, syringed into the mold, and either photocured as before (dual-cure) or allowed to chemically set (self-cure). The total amount of color change (delta E) was calculated using a spectrophotometer after 24 hours (baseline) and after 3, 6, and 12 months of storage in distilled water. Data were analyzed using a repeated measures ANOVA and a Tukey test. After one year of storage, Nexus 3 demonstated the lowest color change values (delta E) under all curing conditions, although it was not significantly different from Variolink 2 when photocured or Calibra when self-cured. New resin cements without a traditional benzoyl peroxide/amine redox initiator system, such as Nexus 3, could be more color-stable over time. PMID:22313825

  20. Stabilizing parquet blocks with epoxy resin

    Directory of Open Access Journals (Sweden)

    S.S. Glazkov

    2015-11-01

    Full Text Available While parquet blocks and panels from stabilized wood show much promise as finishing materials, their widespread use is limited by their low dimensional stability in variable-humidity environments. Existing solutions to stabilize the blocks have several disadvantages, including hard-to-find or toxic stabilizers. This is why this study discusses modifications of epoxy resin which has sufficient functionality for effective structuring. We analyzed the capillary-porous structure of different types of wood, and established the patterns associated with a reduction in the porosity or the specific volume of voids in pine, birch and oak. The basic characteristics of impregnating compositions indicating the high penetrative and structuring capabilities of epoxy resin have been discovered. It is shown that in addition to increasing the strength characteristics, there is a steady decline in water absorption and swelling with an increase in resin content in the wood. It has been found by the method of test fluids that curing the epoxy resin in the presence of hexamethylenediamine is accompanied by a decrease in the proportion of polar components in the total value of the surface tension. Oligomer molecules were shown to penentrate pine wood cells, providing a high moisture protection effect. The results suggest it is possible to use epoxy resin to modify parquet blocks and panels that would be used under variable humidity and high impact loads.

  1. Ordered mesoporous carbon film as an effective solid-phase microextraction coating for determination of benzene series from aqueous media.

    Science.gov (United States)

    Jiang, Hui; Li, Jiansheng; Jiang, Mingyue; Lu, Rui; Shen, Jinyou; Sun, Xiuyun; Han, Weiqing; Wang, Lianjun

    2015-08-12

    The present work reports preparation of ordered mesoporous carbon (OMC) film supported on a graphite fiber as a new type of solid-phase microextraction (SPME) fiber for determination of benzene series from aqueous media. The strategy for the supported OMC film preparation was combined dip-coating technology with solvent evaporation-induced self-assembly (EISA) approach. A graphite fiber was immersed in an ethanol solution containing phenolic resin and Pluronic triblock copolymer. Upon solvent evaporation and subsequent pyrolysis under 700 °C, the phenolic resin and the surfactant self-assembled on the surface of the graphite fiber to form smooth OMC film. X-ray diffraction (XRD), transmission electron microscopy (TEM) and nitrogen isothermal adsorption results indicate that the resultant OMC film possesses well-ordered two dimensional hexagonal mesostructure with pore diameters of 4.5 nm and BET surfaces of 630 m(2)/g. Scanning electron microscopy (SEM) studies show the supported OMC film with thickness at 8.5 ?m is continuous and defect-free. The SPME efficiency of the OMC fiber was evaluated by analysis of five benzene series (benzene, toluene, ethylbenzene, p-xylene and m-xylene) from water samples by gas chromatography-flame ionization detection (GC-FID). The analysis results indicate that the prepared OMC fiber has wide linear ranges (0.5-500 ?g/L), low detection limits (0.01-0.05 ?g/L) and good repeatabilities (4.0-5.8% for one fiber, 2.9-8.7% for fiber-to-fiber). Compared with commercial counterparts, the OMC fiber exhibits improved extraction efficiency for benzene series and PAHs. PMID:26320962

  2. Large-Scale, Three–Dimensional, Free–Standing, and Mesoporous Metal Oxide Networks for High–Performance Photocatalysis

    Science.gov (United States)

    Bai, Hua; Li, Xinshi; Hu, Chao; Zhang, Xuan; Li, Junfang; Yan, Yan; Xi, Guangcheng

    2013-01-01

    Mesoporous nanostructures represent a unique class of photocatalysts with many applications, including splitting of water, degradation of organic contaminants, and reduction of carbon dioxide. In this work, we report a general Lewis acid catalytic template route for the high–yield producing single– and multi–component large–scale three–dimensional (3D) mesoporous metal oxide networks. The large-scale 3D mesoporous metal oxide networks possess large macroscopic scale (millimeter–sized) and mesoporous nanostructure with huge pore volume and large surface exposure area. This method also can be used for the synthesis of large–scale 3D macro/mesoporous hierarchical porous materials and noble metal nanoparticles loaded 3D mesoporous networks. Photocatalytic degradation of Azo dyes demonstrated that the large–scale 3D mesoporous metal oxide networks enable high photocatalytic activity. The present synthetic method can serve as the new design concept for functional 3D mesoporous nanomaterials. PMID:23857595

  3. Natural weathering studies of oil palm trunk lumber (OPTL) green polymer composites enhanced with oil palm shell (OPS) nanoparticles

    OpenAIRE

    Md. Nazrul ISLAM; Dungani, Rudi; Abdul Khalil, HPS; Alwani, M Siti; Nadirah, WO Wan; Fizree, H Mohammad

    2013-01-01

    In this study, a green composite was produced from Oil Palm Trunk Lumber (OPTL) by impregnating oil palm shell (OPS) nanoparticles with formaldehyde resin. The changes of physical, mechanical and morphological properties of the OPS nanoparticles impregnated OPTL as a result of natural weathering was investigated. The OPS fibres were ground with a ball-mill for producing nanoparticles before being mixed with the phenol formaldehyde (PF) resin at a concentration of 1, 3, 5 and 10% w/w basis and...

  4. [Allergic contact eczema from epoxy resin].

    Science.gov (United States)

    Calzado, Leticia; Ortiz-de Frutos, Francisco J; del Prado Sánchez-Caminero, María; Galera, Carmen María; Valverde, Ricardo; Vanaclocha, Francisco

    2005-11-01

    Epoxy resins are plastics that are widely used as electrical insulation, in coatings, and as adhesives and paints. They have strong sensitizing power and are one of the main causes of allergic contact eczema, both in the workplace and elsewhere. We present the case of a worker at a plastics/chemical plant, who handled aeronautical components in the process of manufacturing fuselage parts. He consulted his physician because of eczematous lesions on his fingers, hands and forearms which had developed over a two-year period and were clearly related to his work. The standard battery of skin tests was performed, along with the plastics and adhesives series and tests using the products from his workplace. Positivity was shown to epoxy resins (standard battery) and to the products from his workplace, which included different fiberglass and carbon fiber sheets impregnated with epoxy resins and epoxy adhesives. PMID:16476309

  5. Adsorption of plant phenols by polystyrene resins

    Directory of Open Access Journals (Sweden)

    Akiyoshi Fukushima

    2014-02-01

    Full Text Available Adsorption of nine plant phenols by nine polystyrene ion-exchange resins was investigated in an experimental model system. The phenols were adsorbed by Amberlite CG-120 more efficiently than any other acidically charged resins tested in this study. They were also taken up by anion exchangers. Among them Dowex 1-X8 was found to show the strongest effect on the adsorption of the phenolic constituents applied. A comparison of the efficiency of plant phenol adsorption between two different types of the synthetic polymers revealed that the basically charged polystyrenes had more prefarable affinities for phenols than cation exchangers. For example, the ratio of the efficiency between Amberlite CG-120 and Dowex 1-X8 was roughly calculated to be 3:7 under the present experimental conditions. The adsorption rate of the test phenols was raised mostly by increasing the amount of the resins added, if they were mixed with effective polymers in the incubation model system.

  6. Decontamination capability of epoxy resin coatings

    International Nuclear Information System (INIS)

    The epoxy resin coatings with and without solvents, which have dominated nuclear technology applications, are being replaced more and more frequently by powerful two-component epoxy resin coatings which are emulsifiable with water. This replacement is required for reasons of environmental legislation. To assess the decontamination characteristics and the resistance to chemicals, these three systems were subjected to comparative studies without previous exposure and after gamma irradiation in steps up to 10 Gy. The investigations showed that coats emulsifiable with water performed as well as the solvent-bearing varieties. In this respect, they meet the criteria for coatings in nuclear plants according to the DIN 55991 Part 1 standard. The good properties, such as insensitivity to moisture in concrete, excellent adhesion and adhesion as intermediate layers also on old coatings, are going to help epoxy resin coatings emulsifiable with water win broad application in nuclear medicine and nuclear technology. (orig.)

  7. The influence of resin flexural modulus on the magnitude of ceramic strengthening.

    LENUS (Irish Health Repository)

    Fleming, Garry J P

    2012-07-01

    The aim was to determine the magnitude of ceramic resin-strengthening with resin-based materials with varying flexural moduli using a regression technique to assess the theoretical strengthening at a \\'zero\\' resin-coating thickness. The hypothesis tested was that experimentally, increasing resin flexural modulus results in increased resin-strengthening observed at a theoretical \\'zero\\' resin-coating thickness.

  8. Mesoporous Silica Nanoparticles and Films for Cargo Delivery

    Science.gov (United States)

    Guardado Alvarez, Tania Maria

    Mesoporous silica materials are well known materials that can range from films to nanoparticles. Mesoporous silica nanoparticles (MSNs) and mesoporous silica films have been of increasing interest among the scientific community for its use in cargo delivery. Silica provides ease of functionalization, a robust support and biocompatibility. Several methods have been used in order to give the mesoporous silica nanomaterials different qualities that render them a useful material with different characteristics. Among these methods is surface modification by taking advantage of the OH groups on the surface. When a molecule attached to the surface can act as a molecular machine it transforms the nanomaterial to act as delivery system that can be activated upon command. The work covered in this thesis focuses on the development and synthesis of different mesoporous silica materials for the purpose of trapping and releasing cargo molecules. Chapter 2 focuses in the photoactivation of "snap-top" stoppers over the pore openings of mesoporous silica nanoparticles that releases intact cargo molecules from the pores. The on-command release can be stimulated by either one UV photon or two coherent near-IR photons. Two-photon activation is particularly desirable for use in biological systems because it enables good tissue penetration and precise spatial control. Chapter 3 focuses on the design and synthesis of a nano-container consisting of mesoporous silica nanoparticles with the pore openings covered by "snap-top" caps that are opened by near-IR light. A photo transducer molecule that is a reducing agent in an excited electronic state is covalently attached to the system. Near IR two-photon excitation causes intermolecular electron transfer that reduces a disulfide bond holding the cap in place, thus allowing the cargo molecules to escape. The operation of the "snap-top" release mechanism by both one- and two photon is described. This system presents a proof of concept of a near-IR photoredox-induced nanoparticle delivery system that may lead to a new type of photodynamic drug release therapy. Chapter 4 focuses on the attachment of a photoacid molecule on the surface of silica nanoparticles. Upon light irradiation the pKa of the photoacid molecules decreases causing the dissociation of the proton and the acidification of the nanoparticle surface. The local nanoparticle surface acidification was probed using a pH sensitive nanovalve that was attached to MSNs next to a photoacid. The particles were loaded with a fluorescent dye that was contained by the naovalve and released upon acidification of the surrounding environment. The amount of the dye release was measure continuously by detecting its fluorescence. Chapter 5 focuses on the synthesis of materials that utilize the micropatterned structure of a mesoporous silica film to successfully load and release cargo using a thermal sensitive polymer. Films with pore sizes of ˜2 and ˜5 nm aligned in the pulling direction were synthesized using evaporation induced self-assembly techniques. The pores are exposed using a new method of stamping micropatterns without the use hydrofluoric acid. A well-studied temperature dependent polymer [poly(N-isopropylacrylamide-co-acrylamide)] was grafted onto the surface of these films to act as a temperature activated gatekeeper. Below the lower critical solution temperature (LCST) the polymer is erect and can block the pore openings, trapping cargo inside the pores. When the temperature is above the LCST the polymer collapses and unblocks the pores, allowing cargo to escape. The loading capacities as well as the reusability of these films were studied.

  9. Chemoradiotherapeutic wrinkled mesoporous silica nanoparticles for use in cancer therapy

    Science.gov (United States)

    Munaweera, Imalka; Koneru, Bhuvaneswari; Shi, Yi; Di Pasqua, Anthony J.; Balkus, Kenneth J., Jr.

    2014-11-01

    Over the last decade, the development and application of nanotechnology in cancer detection, diagnosis, and therapy have been widely reported. Engineering of vehicles for the simultaneous delivery of chemo- and radiotherapeutics increases the effectiveness of the therapy and reduces the dosage of each individual drug required to produce an observable therapeutic response. We here developed a novel chemoradiotherapeutic 1,2-dioleoyl-sn-glycero-3-phosphocholine lipid coated/uncoated platinum drug loaded, holmium-containing, wrinkled mesoporous silica nanoparticle. The materials were characterized with TEM, FTIR, 1H NMR, energy dispersive x-ray, inductively coupled plasma-mass spectrometry, and zeta potential measurements. In vitro platinum drug release from both lipid coated and uncoated chemoradiotherapeutic wrinkled mesoporous silica are reported. Various kinetic models were used to analyze the release kinetics. The radioactivity of the chemoradiotherapeutic nanocarriers was measured after neutron-activation.

  10. Catalytic conversion of cellulose over mesoporous Y zeolite.

    Science.gov (United States)

    Park, Young-Kwon; Jun, Bo Ram; Park, Sung Hoon; Jeon, Jong-Ki; Lee, See Hoon; Kim, Seong-Soo; Jeong, Kwang-Eun

    2014-07-01

    Mesoporous Y zeolite (Meso-Y) was applied, for the first time, to the catalytic pyrolysis of cellulose which is a major constituent of lignocellulosic biomass, to produce high-quality bio-oil. A representative mesoporous catalyst Al-MCM-41 was also used to compare its catalytic activity with that of Meso-Y. Pyrolysis-gas chromatography/mass spectrometry was used for the experiments. Meso-Y, with higher acidity, led to larger yields of aromatics and furans with high value-added than Al-MCM-41, resulting in the production of bio-oil with higher quality. The effect of temperature on the catalytic pyrolysis was not significant within the range of 400-500 degrees C. When the Meso-Y to cellulose ratio was increased from 1/1 via 2/1 to 3/1, the deoxygenation efficiency increased, leading to increased yield of aromatics. PMID:24757989

  11. Synthesis, characterization and photocatalytic reactions of phosphated mesoporous titania

    Indian Academy of Sciences (India)

    Pallabi Goswami; Jatindra Nath Ganguli

    2012-10-01

    Mesoporous titania nanoparticles with a well-definedmesostructure was prepared by hydrothermal process, using nonionic triblock copolymer P123 as surfactant template, modified with phosphoric acid and followed by calcination at 600°C. The sol–gel titania was modified by in situ phosphorylation using phosphoric acid and thereby incorporating phosphorous directly into the framework of TiO2. The resulting materials were characterized by XRD, SEM, TEM, nitrogen adsorption, TGA and DRS. It was found that the structural and optical properties of titania samples are strongly influenced by their phosphate modification. In case of calcined samples a positive effect on the specific surface area for the in situ phosphated sample was found. Mesoporous structure of phosphated titania did not collapse even after calcination at 600°C. The enhanced photocatalytic activity of the synthesized phosphate nanomaterials were evaluated through a study of the decomposition of fluorescein under UV light excitation and compared with undoped titania nanomaterial as well as with commercial titania.

  12. Preparation of mesoporous silica films SBA-15 over different substrates

    International Nuclear Information System (INIS)

    Mesoporous materials have been target of frequent interest due to its wide application possibilities, for example development of gas sensors, catalysis, molecules transportation, pharmaceuticals release, synthesis of auto-organized nanostructures, among others. The possibilities of application are enhanced when such materials are disposed in the form of thin and ultrathin films. In this work the preparation of mesoporous SBA-15 silica films is explored by means of the dipcoating technique of a sol-gel on different substrates (glass slides, stainless steel, copper), using the surfactant poly(ethylene glycol)-block-poly(propylene glycol)- block-poly(ethylene glycol), known as P123, a block copolymer. Synthesis parameters surfactant concentration, aging time and temperature were investigated. In this work we present the morphological and structural characterization of the prepared films, which were obtained using atomic force microscopy and x-ray fluorescence and diffraction. (author)

  13. Voltammetric response of ferrocene-grafted mesoporous silica

    International Nuclear Information System (INIS)

    The electrochemical behavior of ferrocene moieties immobilized by covalent grafting on ordered mesoporous silica samples has been studied by cyclic voltammetry in aqueous medium using carbon paste electrodes modified with these solids. The functionalized silica samples were obtained using (3-(ferrocenylamide)propyl)triethoxysilane as the grafting agent. The results have been discussed in relation to the ferrocene content in the materials and compared to those obtained with non-ordered ferrocene-grafted silica gels. Well-defined voltammetric signals have been observed in spite of the insulating character of the mesoporous silica matrix and they were found to increase as a function of the ferrocene groups content in the material. They displayed a better stability upon continuous cycling potentials in comparison to those recorded with amorphous gels, suggesting a beneficial effect of the long-range structural order on the electron transfer processes in such confined media

  14. Interconnected mesopores and high accessibility in UVM-7-like silicas

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Cabero, Monica [Universitat de Valencia, Institut de Ciencia dels Materials (Spain); Hungria, Ana B. [Universidad de Cadiz, Departamento de Ciencia de Materiales, Ingenieria Metalurgica y Quimica Inorganica (Spain); Morales, Jose Manuel [Universitat de Valencia, Institut de Ciencia dels Materials (Spain); Tortajada, Marta; Ramon, Daniel [Biopolis S. L. (Spain); Moragues, Alaina; El Haskouri, Jamal; Beltran, Aurelio; Beltran, Daniel; Amoros, Pedro, E-mail: pedro.amoros@uv.es [Universitat de Valencia, Institut de Ciencia dels Materials (Spain)

    2012-08-15

    Nanoparticulated bimodal mesoporous silicas (NBS) have proved to constitute adequate supports in a variety of applications requiring enhanced accessibility to the active sites. Mass-transfer kinetics seems to be highly favoured in UVM-7-derived NBS materials. To understand the mass-diffusion phenomena throughout UVM-7-like supports requires well-grounded knowledge about their pore architecture. 3-D reconstructions of the UVM-7 mesostructure carried out by electron tomography reveal the existence of a true hierarchic connectivity involving both inter- and intra-nanoparticle pores. This connectivity makes self-supported nanoparticulated mesoporous bimodal carbon replicas of the supports feasible to obtaining by nanocasting. Both the temperature-induced mobility of gold nanodomains and the fast and efficient enzyme adsorption in UVM-7-like silicas are examples of non-constrained diffusion processes happening inside such an open network.

  15. In Mesopore Protein Digestion: A New Forthcoming Strategy in Proteomics

    Directory of Open Access Journals (Sweden)

    Rosa Terracciano

    2011-07-01

    Full Text Available The conventional protocols for in solution or in gel protein digestion require many steps and long reaction times. The use of trypsin immobilized onto solid supports has recently captured the attention of many research groups, because these systems can speed-up protein digestion significantly. The utilization of new materials such as mesoporous silica as supports, in which enzyme and substrate are dramatically concentrated and confined in the nanospace, offers new opportunities to reduce the complexity of proteomics workflows. An overview of the procedures for in situ proteolysis of single proteins or complex protein mixtures is reported, with a special focus on porous materials used as catalysts. The challenging efforts for designing such systems aimed at mimicking the biochemistry of living cells are reviewed. Potentials, limitations and challenges of this branch of enzyme catalysis, which we indicate as in mesopore digestion, are discussed, in relation to its suitability for high-speed and high-throughput proteomics.

  16. Alendronate functionalized mesoporous hydroxyapatite nanoparticles for drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Li, Dongdong, E-mail: lidongchem@sina.cn [State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012 (China); Zhu, Yuntao; Liang, Zhiqiang [State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012 (China)

    2013-06-01

    Highlights: ? The synthesized mesoporous hydroxyapatite has nanostructure and bioactivity. ? The materials have high surface area and amino group. ? The materials show higher drug loading and slower release rate than pure HAP. - Abstract: Mesoporous nanosized hydroxyapatite (HAP) functionalized by alendronate (ALN) was synthesized using cationic surfactant CTAB as template. The structural, morphological and textural properties were fully characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and N{sub 2} adsorption/desorption. Then the obtained materials were performed as drug delivery carriers using ibuprofen (IBU) as a model drug to investigate their drug storage/release properties in simulated body fluid (SBF). The materials showed relatively slower release rate compared with HAP due to the ionic interaction between -NH{sub 3}{sup +} on the matrix and -COO{sup ?}belongs to IBU. The system provides a new concept for improving the drug loading or slowing down the release rate.

  17. Alendronate functionalized mesoporous hydroxyapatite nanoparticles for drug delivery

    International Nuclear Information System (INIS)

    Highlights: ? The synthesized mesoporous hydroxyapatite has nanostructure and bioactivity. ? The materials have high surface area and amino group. ? The materials show higher drug loading and slower release rate than pure HAP. - Abstract: Mesoporous nanosized hydroxyapatite (HAP) functionalized by alendronate (ALN) was synthesized using cationic surfactant CTAB as template. The structural, morphological and textural properties were fully characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and N2 adsorption/desorption. Then the obtained materials were performed as drug delivery carriers using ibuprofen (IBU) as a model drug to investigate their drug storage/release properties in simulated body fluid (SBF). The materials showed relatively slower release rate compared with HAP due to the ionic interaction between -NH3+ on the matrix and -COO?belongs to IBU. The system provides a new concept for improving the drug loading or slowing down the release rate

  18. Chemoradiotherapeutic wrinkled mesoporous silica nanoparticles for use in cancer therapy

    Energy Technology Data Exchange (ETDEWEB)

    Munaweera, Imalka; Balkus, Kenneth J. Jr., E-mail: Balkus@utdallas.edu, E-mail: Anthony.DiPasqua@unthsc.edu [Department of Chemistry, University of Texas at Dallas, 800 West Campbell Rd., Richardson, Texas 75080 (United States); Koneru, Bhuvaneswari; Shi, Yi; Di Pasqua, Anthony J., E-mail: Balkus@utdallas.edu, E-mail: Anthony.DiPasqua@unthsc.edu [Department of Pharmaceutical Sciences, University of North Texas System College of Pharmacy, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, Texas 76107 (United States)

    2014-11-01

    Over the last decade, the development and application of nanotechnology in cancer detection, diagnosis, and therapy have been widely reported. Engineering of vehicles for the simultaneous delivery of chemo- and radiotherapeutics increases the effectiveness of the therapy and reduces the dosage of each individual drug required to produce an observable therapeutic response. We here developed a novel chemoradiotherapeutic 1,2-dioleoyl-sn-glycero-3-phosphocholine lipid coated/uncoated platinum drug loaded, holmium-containing, wrinkled mesoporous silica nanoparticle. The materials were characterized with TEM, FTIR, {sup 1}H NMR, energy dispersive x-ray, inductively coupled plasma-mass spectrometry, and zeta potential measurements. In vitro platinum drug release from both lipid coated and uncoated chemoradiotherapeutic wrinkled mesoporous silica are reported. Various kinetic models were used to analyze the release kinetics. The radioactivity of the chemoradiotherapeutic nanocarriers was measured after neutron-activation.

  19. A series of highly stable mesoporous metalloporphyrin Fe-MOFs.

    Science.gov (United States)

    Wang, Kecheng; Feng, Dawei; Liu, Tian-Fu; Su, Jie; Yuan, Shuai; Chen, Ying-Pin; Bosch, Mathieu; Zou, Xiaodong; Zhou, Hong-Cai

    2014-10-01

    A series of mesoporous metalloporphyrin Fe-MOFs, namely PCN-600(M) (M = Mn, Fe, Co, Ni, Cu), have been synthesized using the preassembled [Fe3O(OOCCH3)6] building block. PCN-600 exhibits a one-dimensional channel as large as 3.1 nm and the highest experimental pore volume of 1.80 cm(3)g(-1) among all the reported porphyrinic MOFs. It also shows very high stability in aqueous solutions with pH values ranging from 2-11 and is to our knowledge the only mesoporous porphyrinic MOF stable under basic aqueous conditions. PCN-600(Fe) has been demonstrated as an effective peroxidase mimic to catalyze the co-oxidation reaction. PMID:25208035

  20. Chemoradiotherapeutic wrinkled mesoporous silica nanoparticles for use in cancer therapy

    Directory of Open Access Journals (Sweden)

    Imalka Munaweera

    2014-11-01

    Full Text Available Over the last decade, the development and application of nanotechnology in cancer detection, diagnosis, and therapy have been widely reported. Engineering of vehicles for the simultaneous delivery of chemo- and radiotherapeutics increases the effectiveness of the therapy and reduces the dosage of each individual drug required to produce an observable therapeutic response. We here developed a novel chemoradiotherapeutic 1,2-dioleoyl-sn-glycero-3-phosphocholine lipid coated/uncoated platinum drug loaded, holmium-containing, wrinkled mesoporous silica nanoparticle. The materials were characterized with TEM, FTIR, 1H NMR, energy dispersive x-ray, inductively coupled plasma-mass spectrometry, and zeta potential measurements. In vitro platinum drug release from both lipid coated and uncoated chemoradiotherapeutic wrinkled mesoporous silica are reported. Various kinetic models were used to analyze the release kinetics. The radioactivity of the chemoradiotherapeutic nanocarriers was measured after neutron-activation.

  1. Chemoradiotherapeutic wrinkled mesoporous silica nanoparticles for use in cancer therapy

    International Nuclear Information System (INIS)

    Over the last decade, the development and application of nanotechnology in cancer detection, diagnosis, and therapy have been widely reported. Engineering of vehicles for the simultaneous delivery of chemo- and radiotherapeutics increases the effectiveness of the therapy and reduces the dosage of each individual drug required to produce an observable therapeutic response. We here developed a novel chemoradiotherapeutic 1,2-dioleoyl-sn-glycero-3-phosphocholine lipid coated/uncoated platinum drug loaded, holmium-containing, wrinkled mesoporous silica nanoparticle. The materials were characterized with TEM, FTIR, 1H NMR, energy dispersive x-ray, inductively coupled plasma-mass spectrometry, and zeta potential measurements. In vitro platinum drug release from both lipid coated and uncoated chemoradiotherapeutic wrinkled mesoporous silica are reported. Various kinetic models were used to analyze the release kinetics. The radioactivity of the chemoradiotherapeutic nanocarriers was measured after neutron-activation

  2. Petroleum Resins: Separation, Character, and Role in Petroleum

    DEFF Research Database (Denmark)

    Andersen, Simon Ivar; Speight, James

    2001-01-01

    In petroleum science, the term resin generally implies material that has been eluted from various solid adsorbents, whereas the term maltenes (or petrolenes) indicates a mixture of the resins and oils obtained as filtrates from the asphaltene precipitation. Thus, after the asphaltenes are precipitated, adsorbents are added to the n-pentane solutions of the resins and oils, by which process the resins are adsorbed and subsequently recovered by the use of a more polar solvent, and the oils remain ...

  3. Studies on ion-exchange resin complex of Dextromethorphan Hydrobromide

    OpenAIRE

    Malladi, Madhusudhan; Jukanti, Raju; Nair, Rashmi; Wagh, Sanjay; Padakanti, Harishanker

    2010-01-01

    The objective of present work was to assess ion exchange resins for taste masking of Dextromethorphan Hydrobromide (DM) - a highly bitter drug. A strong cationic exchange resin (Amberlite® IRP-69) and weak cationic exchange resin (Amberlite® IRP-64) were evaluated. Based on drug loading efficiency, Amberlite® IRP-69 was selected for further evaluation. The effect of different methods of drug loading, drug: resin ratios and particle size on drug complexation was evaluated. The formation of a r...

  4. Recovery of tretrachloroaurate through ion exchange with Dowex 11 resin

    International Nuclear Information System (INIS)

    The recovery of the tretrachloroaurate complex by the anionic ion exchange resin Dowex 11 has been studied. The kinetics of gold adsorption were dependent of both gold and resin concentrations and temperature. The adsorption isotherm can be described by the expression Q=kC''n. The loaded resin could be eluted by an acidic thiourea solution at 20 degree centigree. After several adsorption-elution cycles there is not any apparent loss in the adsorption properties of the resin. (Author) 6 refs

  5. Comparative Mechanical Properties of Bulk-Fill Resins

    OpenAIRE

    Atabek Didem; Yalç?n Gözde; Özta? Nurhan

    2014-01-01

    Aim: The aim of this study was to compare the flexural and compressive strengths of a new sonicactivated bulk-fill system (Sonicfill) with other bulk-fill resins and a universal posterior composite resin. Materials and Methods: A low-stress flowable base resin material (SDR), a bulk-fill composite resin (Tetric Evo Ceram), a universal posterior composite (GC G-aenial), and the Sonicfill system were compared. The specimens were prepared for each group following ISO St...

  6. Gamma-irradiation on cured glycidyl amino-epoxy resin

    International Nuclear Information System (INIS)

    ITER is an international project to design and build an experimental fusion reactor based on the superconductive 'tokamak' concept. Amounts of epoxy resin are used in the superconductive tokamak device as impregnant resins, insulation breaks, etc. Resistance to ionizing radiation is a demanding performance of those epoxy resins. In this work, we study the effects of ?-irradiation on the mechanical properties and chemical structures of glycidyl amino-epoxy resins

  7. ORAL CONTROLLED RELEASE METFORMIN HYDROCHLORIDE ION EXCHANGE RESINATE BEADS

    OpenAIRE

    Ajit S. Raghuwanshi; U. K. Jain; Ajay S. Raghuwanshi

    2010-01-01

    Treating with ion exchange resin has chemically modified metformin hydrochloride to form an oral controlled release beads using ion-exchange resin sorption method. A strong cation exchange resin Amberlite IR 120 was utilized for the sorption of the drug and the drug resinates was evaluated for various physical and chemical parameters. The drug content and percentage drug release were determined spectrophotometrically at 233 nm. About 43% of drug was loaded in 4.5 h and in-vitro dissolution st...

  8. Study on Bismaleimide Modified TDE-86 Epoxy Resin

    OpenAIRE

    Daofang Shi; Xiaoqing Wu

    2010-01-01

    In the study, BMI was modified by Ortho-diallyl Bisphenol A under certain conditions and got performed polymer. Epoxy resin was modified by the performed polymer using nadic methyl anhydride (MNA) as curing agent. The study investigated the manufacturability, thermal and mechanical properties of modified resin. The manufacturability of the modified resin was indicated by viscosity- temperature, viscosity- time and the gel time curves. Thermal properties of modified resin were characterized by...

  9. Treatment of spent ion-exchange resins by incorporation into epoxy resin

    International Nuclear Information System (INIS)

    Epoxy resin was used as an incorporation medium for inactive and labelled simulated spent ion-exchange resin. The quality of the final waste form has been defined using mechanical, thermal and homogeneity tests. Irradiation stability was studied by treating the end product with increasing doses before subjecting to mechanical tests. As for as the thermal stability is concerned, degradation occurs only above 280 C as shown by T G, DTG and DTA curves. The cumulative teach fractions were higher for both Ru-106 and Cs 137 than for Ce 144 labelled incorporated ion-exchange resin.2 tab., 5 fig

  10. Evaluation of marginal leakage between a flowable composite resin and resin-modified glass ionomer cements

    Directory of Open Access Journals (Sweden)

    Álvaro VOLPATO

    2005-11-01

    Full Text Available The aim of the present study was to evaluate, in vitro, the leakage between a flowable composite resin (Fill Magic Flow® and resin-modified glass ionomer cements (Vitremer®. Forty extracted human premolars were selected for this study. The teeth were randomly assigned into two groups. Class cavities were prepared with margin extended apically. All teeth were subjected to thermocycling with 250 cycles. Afterwards, the teeth were submitted to a basic fuccina 0,5% to be analyzed to the infiltration degree throughout the walls of the preparation. The results showed that resin-modified glass ionomer cements present the worst results (p < 0,05.

  11. Lewis acidity of mesoporous molecular sieves for acylation reactions.

    Czech Academy of Sciences Publication Activity Database

    Voláková, Martina; Vlk, Josef; Vitvarová, Dana; Šiklová, Helena; ?ejka, Ji?í

    Singapore : World Scientific Publ. Co. Pte. Ltd, 2008 - (Sayari, A.; Jaroniec, M.), s. 477-486 ISBN 978-981-277-915-1. [Nanoporous Materials /5./. Vancouver (CA), 25.05.2008-28.05.2008] R&D Projects: GA ?R GA104/07/0383 Institutional research plan: CEZ:AV0Z40400503 Keywords : mesoporous molecular sieves * Lewis acid ity * acylation reactions Subject RIV: CF - Physical ; Theoretical Chemistry

  12. Electronic Parameters of Mesoporous Silicon Upon Adsorption of Plant Viruses

    Science.gov (United States)

    Vashpanov, Yuriy; Son, Jung-Young; Kwack, Kae-Dal; Shin, Seung-Jung

    2008-06-01

    Changes in the electronic parameters of mesoporous silicon upon adsorption of nematodetransmitted polyhedral (NEPO) viruses of plant [tomato ringspot virus (TORSV), grapevine virus A (GVA), and grapevine fan leaf virus (GFLV)] measured at room temperature are investigated. The adsorption of these viruses affected essentially on the electronic characteristic of the porous material. The measurement of the electronic characteristics of porous silicon can be applied to the creation of detectors for the presence of viruses in a given environment.

  13. NiW Hydrodesulfurization Catalysts Supported on Mesoporous Titanate Nanotubes.

    Czech Academy of Sciences Publication Activity Database

    Dimitrov, L.; Palcheva, R.; Spojakina, A.A.; Jirátová, Kv?ta

    Sofia : -, 2009 - ( Petrova , G.; Vayssilov, G.), s. 129 ISBN 978-954-323-558-2. [International Symposium Advanced Micro- and Mesoporous Materials /3./. Albena (BG), 06.09.2009-09.09.2009] Grant ostatní: NSF(BG) TK01/0416 Institutional research plan: CEZ:AV0Z40720504 Keywords : titanate nanotubes * catalytic activity * hydrodesulfurization Subject RIV: CC - Organic Chemistry http://bg-conferences.org/micro2009_new_1/

  14. Hierarchically structured biphenylene-bridged periodic mesoporous organosilica

    OpenAIRE

    Li, Yan; Keilbach, Andreas; Kienle, Marcel; GOTO, YASUTOMO; Inagaki, Shinji; Knoche, Paul; Bein, Thomas

    2011-01-01

    Novel composites of highly ordered and stable biphenyl-bridged periodic mesoporous organosilica (PMO) materials confined within the pores of anodic alumina membranes (AAM) were successfully synthesized by evaporation-induced self-assembly (EISA). 4,40-Bis(triethoxysilyl)biphenyl (BTEBP) was used as a precursor in combination with the ionic surfactant cetyltrimethylammonium bromide (CTAB) or triblock-copolymer F127 as structure-directing agents. The resulting mesophases were cha...

  15. Formation of mesoporous SBA-15 from a colloidal perspective

    OpenAIRE

    Linton, Peter

    2009-01-01

    The formation of the hexagonal ordered mesoporous SBA-15 material has been invetsigated. The evolution from free spherical micelles into an ordered material was studied with time-resolved in-situ SAXS, USAXS and SANS measurements. Both the mesoscopic region and the colloidal region were monitored. Temperature, precursor and salt additions have been varied. From the time-resolved measurements the events taking place in the formation of SBA-15 was identified and put on a time line. An additiona...

  16. Ordered mesoporous silica carrier system applied in nanobiothecnology

    OpenAIRE

    Andreza de Sousa; Edésia Martins Barros de Sousa

    2005-01-01

    Ordered mesoporous materials like SBA15 possess a network of channels and pores of well-defined size in the nanoscale range (2-50 nm). This particular pore architecture makes them suitable candidates for hosting and delivery under appropriate conditions of a variety of molecules of pharmaceutical interest, including radiopharmaceuticals. The characteristics of SBA-15 prepared in different temperatures and the behavior of this system regarding microencapsulation of a model drug were investigat...

  17. Treatment of Methaqualone overdose with resin hemoperfusion.

    OpenAIRE

    Baggish, D.; Gray, S.; Jatlow, P; Bia, M. J.

    1981-01-01

    We recently utilized the technique of resin hemoperfusion (employing an Amberlite XAD-4 resin cartridge) to remove drug from a patient i deep coma after an estimated ingestion of greater than 4.5 grams of methaqualone. At plasma flow rates of 204 ml/min, the mean value for plasma clearance of methaqualone was 179 ml/min. The amount of methaqualone recovered from the cartridge at the end of the 10-hour procedure was 1,565 mg measured by gas chromatography. The patient became responsive to deep...

  18. Resin transfer molding of textile composites

    Science.gov (United States)

    Falcone, Anthony; Dursch, Harry; Nelson, Karl; Avery, William

    1993-01-01

    The design and manufacture of textile composite panels, tubes, and angle sections that were provided to NASA for testing and evaluation are documented. The textile preform designs and requirements were established by NASA in collaboration with Boeing and several vendors of textile reinforcements. The following four types of preform architectures were used: stitched uniweave, 2D-braids, 3D-braids, and interlock weaves. The preforms consisted primarily of Hercules AS4 carbon fiber; Shell RSL-1895 resin was introduced using a resin transfer molding process. All the finished parts were inspected using ultrasonics.

  19. Ordered nanowire arrays in the mesoporous silica thin films

    International Nuclear Information System (INIS)

    In the present study we report synthesis and investigation of the magnetic iron nanowire arrays in the mesoporous silica thin films. The films were deposited on SiC/Si(100) substrate by spin-coating technique, enabling one to obtain all mesopores parallel to the substrate surface and aligned radially by centrifugal force. Very high level of local alignment (90% on 2 cm2) of the pores was proved by small angle X-ray scattering and neutron reflectivity. Magnetic iron nanowires were synthesized in the mesoporous silica channels by intercalation of a hydrophobic iron compound into a hydrophobic part of the silica-surfactant composite followed by decomposition of the complex and additional crystallization of iron in hydrogen flow. Nanocomposites were studied by TEM, ED, SAXS, BET, BJH and neutron reflectometry. It was found that an ordered structure preserves after the chemical modification, while iron nanowires uniformly fill porous structure, making this system highly promising for high-density data recording media

  20. Sustained release of fungicide metalaxyl by mesoporous silica nanospheres

    Energy Technology Data Exchange (ETDEWEB)

    Wanyika, Harrison, E-mail: hwanyika@gmail.com [Jomo Kenyatta University of Agriculture and Technology, Department of Chemistry (Kenya)

    2013-08-15

    The use of nanomaterials for the controlled delivery of pesticides is nascent technology that has the potential to increase the efficiency of food production and decrease pollution. In this work, the prospect of mesoporous silica nanoparticles (MSN) for storage and controlled release of metalaxyl fungicide has been investigated. Mesoporous silica nanospheres with average particle diameters of 162 nm and average pore sizes of 3.2 nm were prepared by a sol-gel process. Metalaxyl molecules were loaded into MSN pores from an aqueous solution by a rotary evaporation method. The loaded amount of metalaxyl as evaluated by thermogravimetric analysis was about 14 wt%. Release of the fungicide entrapped in the MSN matrix revealed sustained release behavior. About 76 % of the free metalaxyl was released in soil within a period of 30 days while only 11.5 and 47 % of the metalaxyl contained in the MSN carrier was released in soil and water, respectively, within the same period. The study showed that MSN can be used to successfully store metalaxyl molecules in its mesoporous framework and significantly delay their release in soil.

  1. Catalytic upgrading of xylan over mesoporous Y catalyst.

    Science.gov (United States)

    Kim, Seong-Soo; Jun, Bo Ram; Park, Sung Hoon; Jeon, Jong-Ki; Suh, Dong Jin; Kim, Tae-Wan; Park, Young-Kwon

    2014-04-01

    In-situ catalytic cracking of xylan, a model compound of hemicellulose, was carried out using pyrolysis-gas chromatography/mass spectrometry over mesoporous Y for the first time. Experiments were conducted at three different temperatures, 400 degrees C, 450 degrees C, and 500 degrees C, to investigate the effect of reaction temperature. Three different biomass-to-catalyst ratios, 1:1, 1:2, and 1:3, were tested at 500 degrees C to examine the effect of catalyst dose. In addition, the catalytic activity of mesoporous Y was compared with that of Al-MCM-41. The catalysts used were characterized by N2 adsorption-desorption, temperature programmed desorption of NH3, and X-ray diffraction. The main pyrolysis products of xylan were acids, hydrocarbons, phenolics, oxygenates, aromatics, and polycyclic aromatic hydrocarbons. Mesoporous Y, which has acid sites with larger quantity and stronger acidity than those of Al-MCM-41, was shown to enhance the quality of bio-oil to a larger extent, producing a larger quantity of high-value-added products, such as aromatics and furans. PMID:24734712

  2. Soft-Template-Synthesized Mesoporous Carbon for Oral Drug Delivery

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Dipendu [ORNL; Warren, Kaitlyn E [ORNL; Naskar, Amit K [ORNL

    2014-01-01

    Template-synthesized mesoporous carbons were successfully used in in vitro investigations of controlled delivery of three model drugs, captopril, furosemide, and ranitidine hydrochloride. Captopril and furosemide exhibited desorption kinetics over 30 40 h, and ranitidine HCl had a complete release time of 5 10 h. As evident from the slow release kinetics, we contend that our mesoporous carbon is an improved drug-delivery medium compared to state-of-the-art porous silica-based substrates. The mesoporous carbons, synthesized from phloroglucinol and lignin, a synthetic and a sustainable precursor, respectively, exhibit BET surface area of 200 400 m2 g-1 and pore volume of 0.2 0.6 cm3 g-1. The phloroglucinol-based carbon has narrower pore widths and higher pore volume than the lignin-derived counterpart and maintains a longer release time. Numerical modeling of the release kinetics data reveals that the diffusivities of all the drugs from lignin-based carbon media are of equivalent magnitude (10-22 to 10-24 m2 s-1). However, a tailored reduction of pore width in the sorbent reduces the diffusivity of smaller drug molecules (captopril) by an order of magnitude. Thus, engineered pore morphology in our synthesized carbon sorbent, along with its potential to tailor the chemistry of its interaction with sorbet, can be exploited for optimal delivery system of a preferred drug within its therapeutic level and below the level of toxicity.

  3. Functionalized mesoporous silica nanoparticles for oral delivery of budesonide

    International Nuclear Information System (INIS)

    Non-functionalized and amino-functionalized mesoporous silica nanoparticle were loaded with anti-inflammatory drug budesonide and additionally post-coated with bioadhesive polymer (carbopol). TEM images showed spherical shape of the nanoparticles and slightly higher polydispersity after coating with carbopol. Nitrogen physisorption and thermogravimetic analysis revealed that more efficient loading and incorporation into the pores of nanoparticles was achieved with the amino-functionalized silica carrier. Infrared spectra indicated that the post-coating of these nanoparticles with carbopol led to the formation of bond between amino groups of the functionalized carrier and carboxyl groups of carbopol. The combination of amino-functionalization of the carrier with the post-coating of the nanoparticles sustained budesonide release. Further, an in vitro model of inflammatory bowel disease showed that the cytoprotective effect of budesonide loaded in the post-coated silica nanoparticles on damaged HT-29 cells was more pronounced compared to the cytoprotection obtained with pure budesonide. -- Graphical abstract: Silica mesoporous MCM-41 particles were amino-functionalized, loaded with budesonide and post-coated with bioadhesive polymer (carbopol) in order to achieve prolonged residence of anti-inflammatory drug in GIT. Highlights: • Higher drug loading in amino-functionalized mesoporous silica. • Amino-functionalization and post-coating of the nanoparticles sustained drug release. • Achievement of higher cytoprotective effect with drug loaded into the nanoparticles

  4. Mesoporous hydroxyapatite: Preparation, drug adsorption, and release properties

    International Nuclear Information System (INIS)

    Mesoporous hydroxyapatite (HA) was synthesized through gas–liquid chemical precipitation method at ambient temperature without any template. Structure, morphology and pore size distribution of HA were analyzed via X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution electron microscopy and N2 adsorption/desorption. The chemotherapeutic agent doxorubicin (DOX) was used to investigate the drug adsorption and release behavior of HA. The kinetics of DOX adsorption on HA followed the pseudo-second-order rate expression. Adsorption isotherms at various temperatures were obtained, and the equilibrium data fitted the Langmuir model. The values of thermodynamic parameters (Gibbs free energy, entropy, and enthalpy changes) demonstrated that the adsorption process was spontaneous and endothermic. In vitro pH-responsive (pH = 7.4, 5.8) controlled release was investigated. DOX-loaded HA showed a slow, long-term, and steady release rate. The release rate at pH5.8 was larger than that at pH7.4. Consequently, the as-prepared mesoporous HA has potential applications in controlled drug delivery systems. - Highlights: • Mesoporous HA was synthesized by a simple precipitation method without any template. • The kinetics of adsorption followed the pseudo-second-order rate expression. • Thermodynamics investigation showed that adsorption was spontaneous and endothermic. • DOX-loaded HA showed a long-term, steady, and pH-controlled release rate

  5. Aerosol-spray diverse mesoporous metal oxides from metal nitrates.

    Science.gov (United States)

    Kuai, Long; Wang, Junxin; Ming, Tian; Fang, Caihong; Sun, Zhenhua; Geng, Baoyou; Wang, Jianfang

    2015-01-01

    Transition metal oxides are widely used in solar cells, batteries, transistors, memories, transparent conductive electrodes, photocatalysts, gas sensors, supercapacitors, and smart windows. In many of these applications, large surface areas and pore volumes can enhance molecular adsorption, facilitate ion transfer, and increase interfacial areas; the formation of complex oxides (mixed, doped, multimetallic oxides and oxide-based hybrids) can alter electronic band structures, modify/enhance charge carrier concentrations/separation, and introduce desired functionalities. A general synthetic approach to diverse mesoporous metal oxides is therefore very attractive. Here we describe a powerful aerosol-spray method for synthesizing various mesoporous metal oxides from low-cost nitrate salts. During spray, thermal heating of precursor droplets drives solvent evaporation and induces surfactant-directed formation of mesostructures, nitrate decomposition and oxide cross-linking. Thirteen types of monometallic oxides and four groups of complex ones are successfully produced, with mesoporous iron oxide microspheres demonstrated for photocatalytic oxygen evolution and gas sensing with superior performances. PMID:25897988

  6. Benzylation of Toluene over Iron Modified Mesoporous Ceria

    Directory of Open Access Journals (Sweden)

    K.J. Rose Philo

    2012-12-01

    Full Text Available Green chemistry has been looked upon as a sustainable science which accomplishes both economical and environmental goals, simultaneously.With this objective, we developed an alternative process to obtain the industrially important benzyl aromatics by benzylation of aromatics using benzyl chloride, catalysed by mesoporous solid acid catalysts. In this work mesoporous ceria is prepared using neutral surfactant which helped the calcination possible at a lower temperature enabling a higher surface area. Mesoporous ceria modified with Fe can be successfully utilized for the selective benzylation of toluene to more desirable product methyl diphenyl methane with 100% conversion and selectivity in 2 hours using only 50mg of the catalyst under milder condition. The reusability, regenerability, high selectivity, 100% conversion, moderate reaction temperature and absence of solvent, etc. make these catalysts to be used in a truly heterogeneous manner and make the benzylation reaction an environment friendly one. Copyright © 2012 by BCREC UNDIP. All rights reservedReceived: 30th June 2012; Revised: 7th November 2012; Accepted: 10th November 2012[How to Cite: K.J. Rose Philo, S. Sugunan. (2012. Benzylation of Toluene over Iron Modified Mesoporouxs Ceria. Bulletin of Chemical Reaction Engineering & Catalysis, 7(2: 158-164. (doi:10.9767/bcrec.7.2.3759.158-164][How to Link / DOI: http://dx.doi.org/10.9767/bcrec.7.2.3759.158-164 ] | View in 

  7. Mesoporous hydroxyapatite: Preparation, drug adsorption, and release properties

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Lina; He, Xiaomei; Wu, Zhenyu, E-mail: zhenyuwuhn@sina.com

    2014-11-14

    Mesoporous hydroxyapatite (HA) was synthesized through gas–liquid chemical precipitation method at ambient temperature without any template. Structure, morphology and pore size distribution of HA were analyzed via X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution electron microscopy and N{sub 2} adsorption/desorption. The chemotherapeutic agent doxorubicin (DOX) was used to investigate the drug adsorption and release behavior of HA. The kinetics of DOX adsorption on HA followed the pseudo-second-order rate expression. Adsorption isotherms at various temperatures were obtained, and the equilibrium data fitted the Langmuir model. The values of thermodynamic parameters (Gibbs free energy, entropy, and enthalpy changes) demonstrated that the adsorption process was spontaneous and endothermic. In vitro pH-responsive (pH = 7.4, 5.8) controlled release was investigated. DOX-loaded HA showed a slow, long-term, and steady release rate. The release rate at pH5.8 was larger than that at pH7.4. Consequently, the as-prepared mesoporous HA has potential applications in controlled drug delivery systems. - Highlights: • Mesoporous HA was synthesized by a simple precipitation method without any template. • The kinetics of adsorption followed the pseudo-second-order rate expression. • Thermodynamics investigation showed that adsorption was spontaneous and endothermic. • DOX-loaded HA showed a long-term, steady, and pH-controlled release rate.

  8. Functionalized mesoporous silica nanoparticles for oral delivery of budesonide

    Energy Technology Data Exchange (ETDEWEB)

    Yoncheva, K., E-mail: krassi.yoncheva@gmail.com [Department of Pharmaceutical Technology, Faculty of Pharmacy, Medical University of Sofia, 2 Dunav Str., 1000 Sofia (Bulgaria); Popova, M. [Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia (Bulgaria); Szegedi, A.; Mihaly, J. [Institute of Nanochemistry and Catalysis, Chemical Research Center, Hungarian Academy of Sciences, Pusztaszeri út. 59-67, 1025 Budapest (Hungary); Tzankov, B.; Lambov, N.; Konstantinov, S.; Tzankova, V. [Department of Pharmaceutical Technology, Faculty of Pharmacy, Medical University of Sofia, 2 Dunav Str., 1000 Sofia (Bulgaria); Pessina, F.; Valoti, M. [Dipartimento di Scienze della Vita, Universita di Siena, via Aldo Moro 2, Siena (Italy)

    2014-03-15

    Non-functionalized and amino-functionalized mesoporous silica nanoparticle were loaded with anti-inflammatory drug budesonide and additionally post-coated with bioadhesive polymer (carbopol). TEM images showed spherical shape of the nanoparticles and slightly higher polydispersity after coating with carbopol. Nitrogen physisorption and thermogravimetic analysis revealed that more efficient loading and incorporation into the pores of nanoparticles was achieved with the amino-functionalized silica carrier. Infrared spectra indicated that the post-coating of these nanoparticles with carbopol led to the formation of bond between amino groups of the functionalized carrier and carboxyl groups of carbopol. The combination of amino-functionalization of the carrier with the post-coating of the nanoparticles sustained budesonide release. Further, an in vitro model of inflammatory bowel disease showed that the cytoprotective effect of budesonide loaded in the post-coated silica nanoparticles on damaged HT-29 cells was more pronounced compared to the cytoprotection obtained with pure budesonide. -- Graphical abstract: Silica mesoporous MCM-41 particles were amino-functionalized, loaded with budesonide and post-coated with bioadhesive polymer (carbopol) in order to achieve prolonged residence of anti-inflammatory drug in GIT. Highlights: • Higher drug loading in amino-functionalized mesoporous silica. • Amino-functionalization and post-coating of the nanoparticles sustained drug release. • Achievement of higher cytoprotective effect with drug loaded into the nanoparticles.

  9. Conductivity of liquid lithium electrolytes with dispersed mesoporous silica particles

    International Nuclear Information System (INIS)

    Highlights: ? The conductivity of disperse lithium electrolytes with mesoporous fillers is studied. ? In contrast to other investigations in literature, no conductivity enhancement could be observed for standard battery electrolytes and typical mesoporous fillers in various combinations. ? Disperse electrolytes can become relevant in terms of battery safety. ? Dispersions of silicas and electrolyte with LiPF6 as conducting salt are not stable, although the silicas were dried prior to preparation and the electrolyte water content was controlled. Surface modification of the fillers improved the stability. ? The observed conductivity decrease varied considerably for various fillers. - Abstract: The electrical conductivity of disperse electrolytes was systematically measured as a function of temperature (0 °C to 60 °C) and filler content for different types of fillers with a range of pore geometry, pore structure and specific surface area. As fillers mesoporous silicas SBA-15, MCM-41 and KIT-6 with pore ranges between 3 nm and 15 nm were dispersed in commercially available liquid lithium electrolytes. As electrolytes 1 M of lithium hexafluorophosphate (LiPF6) in a mixture of ethylene carbonate (EC) and diethylene carbonate (DEC) at the ratio 3:7 (wt/wt) and the same solvent mixture with 0.96 M lithium bis(trifluoromethanesulfon)imide (LiTFSI) were used. No conductivity enhancement could be observed, but with respect to safety aspects the highly viscous disperse pastes might be useful. The conductivity decrease varied considerably for the different fillers.

  10. Curing reaction of bisphenol-A based benzoxazine with cyanate ester resin and the properties of the cured thermosetting resin

    Directory of Open Access Journals (Sweden)

    H. Kimura

    2011-12-01

    Full Text Available Curing reaction of bisphenol-A based benzoxazine with cyanate ester resin and the properties of the cured thermosetting resin were investigated. The cure behavior of benzoxazine with cyanate ester resin was monitored by model reaction using nuclear magnetic resonance (NMR. As a result of the model reaction, the ring opening reaction of benzoxazine ring and thermal self-cyclotrimerization of cyanate ester group occurred, and then the phenolic hydoroxyl group generated by the ring opening reaction of benzoxazine ring co-reacted with cyanate ester group. The properties of the cured thermosetting resin were estimated by mechanical properties, electrical resistivity, water resistance and heat resistance. The cured thermosetting resin from benzoxazine and cyanate ester resin showed good heat resistance, high electrical resistivity and high water resistance, compared with the cured thermosetting resin from benzoxazine and epoxy resin.

  11. Occupational asthma due to unheated polyvinylchloride resin dust.

    OpenAIRE

    Lee, H.S.; Yap, J; Wang, Y T; Lee, C. S.; Tan, K. T.; Poh, S. C.

    1989-01-01

    Polyvinylchloride (PVC) resins are widely used in industry. Asthma due to the thermal degradation products of PVC are well documented. In this first case of occupational asthma due to unheated PVC resin dust the patient was exposed to PVC resin dust during the mixing of chemicals used for making plastic seals for bottle caps.

  12. 21 CFR 173.40 - Molecular sieve resins.

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 2009-04-01 true Molecular sieve resins. 173.40 Section 173.40 Food and...Adjuvants for Food Treatment § 173.40 Molecular sieve resins. Molecular sieve resins may be safely used in the processing of...

  13. Electron sensitive resin and fabrication process of this one

    International Nuclear Information System (INIS)

    The invention concerns electron sensitive negative resins, that is to say the resins which, when subjected to the action of an electronic beam of adequate power, undergo a transformation that makes them resistant to certain chemical agents or insoluble in certain solvents. The invention also concerns a process for manufacturing this resin which is a 2.3 epithiopropylmethacrylate copolymer

  14. 21 CFR 177.2410 - Phenolic resins in molded articles.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Phenolic resins in molded articles. 177.2410... as Components of Articles Intended for Repeated Use § 177.2410 Phenolic resins in molded articles. Phenolic resins identified in this section may be safely used as the food-contact surface of...

  15. 40 CFR 721.5908 - Modified phenolic resin (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Modified phenolic resin (generic). 721... Substances § 721.5908 Modified phenolic resin (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as modified phenolic resin (PMN...

  16. 40 CFR 721.5762 - Aromatic aldehyde phenolic resin (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Aromatic aldehyde phenolic resin... Specific Chemical Substances § 721.5762 Aromatic aldehyde phenolic resin (generic). (a) Chemical substance... aromatic aldehyde phenolic resin (PMN P-01-573) is subject to reporting under this section for...

  17. 40 CFR 721.5905 - Modified phenolic resin (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Modified phenolic resin (generic). 721... Substances § 721.5905 Modified phenolic resin (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a modified phenolic resin...

  18. 40 CFR 721.3135 - Phosphorous modified epoxy resin (generic).

    Science.gov (United States)

    2010-07-01

    ...2010-07-01 false Phosphorous modified epoxy resin (generic). 721.3135 Section...Substances § 721.3135 Phosphorous modified epoxy resin (generic). (a) Chemical substance...identified generically as a phosphorous modified epoxy resin (PMNs P-00-992 and...

  19. 76 FR 39896 - Granular Polytetrafluoroethylene Resin From Italy

    Science.gov (United States)

    2011-07-07

    ... Granular Polytetrafluoroethylene Resin From Italy Determination On the basis of the record \\1\\ developed in... antidumping duty order on granular polytetrafluoroethylene resin from Italy would be likely to lead to... Granular Polytetrafluoroethylene Resin from Italy: Investigation No. 731-TA-385 (Third Review). By order...

  20. 21 CFR 177.2355 - Mineral reinforced nylon resins.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Mineral reinforced nylon resins. 177.2355 Section... as Components of Articles Intended for Repeated Use § 177.2355 Mineral reinforced nylon resins. Mineral reinforced nylon resins identified in paragraph (a) of this section may be safely used as...

  1. Photosensitive filler minimizes internal stresses in epoxy resins

    Science.gov (United States)

    Dillon, J. N.

    1967-01-01

    Photosensitive filler is added to curable epoxy resins to minimize stress from internal shrinkage during curing or polymerization. Cinnamic acid resins and cinnamal ketones may be added in the amount of 1 to 3 percent by weight of the resin mixture.

  2. 21 CFR 175.270 - Poly(vinyl fluoride) resins.

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 2009-04-01 true Poly(vinyl fluoride) resins. 175.270 Section 175.270...Components of Coatings § 175.270 Poly(vinyl fluoride) resins. Poly(vinyl fluoride) resins identified in this section...

  3. 40 CFR 721.3135 - Phosphorous modified epoxy resin (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phosphorous modified epoxy resin... Specific Chemical Substances § 721.3135 Phosphorous modified epoxy resin (generic). (a) Chemical substance... phosphorous modified epoxy resin (PMNs P-00-992 and P-01-471) is subject to reporting under this section...

  4. 40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Epoxy resin containing phosphorus... Specific Chemical Substances § 721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance... epoxy resin containing phosphorus (PMN P-00-912) is subject to reporting under this section for...

  5. 40 CFR 721.2755 - Cycloaliphatic epoxy resin (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Cycloaliphatic epoxy resin (generic... Substances § 721.2755 Cycloaliphatic epoxy resin (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as cycloaliphatic epoxy resin...

  6. Development of radiation-curable resin based on natural rubber

    International Nuclear Information System (INIS)

    A new radiation curable resin based on natural rubber has been developed. The resin was based on the reaction between low molecular weight epoxidised natural rubber and acrylic acid. When formulated with reactive monomers and photoinitiator, it solidified upon irradiation with UV light. The resin may find applications in coating for cellulosic-based substrates and pressure-sensitive adhesive

  7. Effect of polysulfonate resins and direct compression fillers on multiple-unit sustained-release dextromethorphan resinate tablets

    OpenAIRE

    Pongjanyakul, Thaned; Priprem, Aroonsri; Chitropas, Padungkwan; Puttipipatkhachorn, Satit

    2005-01-01

    The purpose of this work was to investigate the effect of different polysulfonate resins and direct compression fillers on physical properties of multiple-unit sustained-release dextromethorphan (DMP) tablets. DMP resinates were formed by a complexation of DMP and strong cation exchange resins, Dowex 50 W and Amberlite IRP69. The tablets consisted of the DMP resinates and direct compression fillers, such as microcrystalline cellulose (MCC), dicalcium phosphate dihydrate (DCP), and spray-dried...

  8. Effect of epoxy resin properties on the mechanical properties of carbon fiber/epoxy resin composites

    Energy Technology Data Exchange (ETDEWEB)

    He, Hong-Wei; Gao, Feng [Taiyuan Univ. of Technology (China). College of Materials Science and Engineering; Taiyuan Univ. of Technology (China). Key Laboratory of Interface Science and Engineering in Advanced Materials; Li, Kai-Xi [Chinese Academy of Sciences, Taiyuan, Shanxi (China). Key Laboratory of Carbon Materials

    2013-09-15

    Three kinds of epoxy resins, i.e. tetraglycidyl diaminodiphenyl methane (AG80), difunctional diglycidyl ether of bisphenol-A (E51) and novolac type epoxy resin (F46) were selected as matrices for carbon fiber/epoxy composites. The objective of this work is to study the mechanical properties of fiber/epoxy composites by using these three kinds of epoxy resins with different physical and chemical performance. The results show that the composites fabricated with AG80 present the best stiffness and the composites prepared with E5 1have the best toughness. The stiffness and toughness of the composites prepared with F46 are middle values located between those for AG80/epoxy and E51/epoxy composites. Thus, the mixed epoxy resin is a promising approach for industrial production. (orig.)

  9. Hydroisomerization of hexane over micro-mesoporous zeolites with tailored structure and distribution of active sites.

    Czech Academy of Sciences Publication Activity Database

    Kaucký, Dalibor; Janošcová, J.; Tabor, Edyta; Rathouský, Ji?í; Klein, P.; Sazama, Petr

    Caen : ENSICAEN, Université de Caen, 2015. s. 89-89. [International Symposium Advances Micro- and Mesoporous Materials /6./. 06.09.2015-09.09.2015, Sunset - Black Sea] R&D Projects: GA ?R GA15-12113S Institutional support: RVO:61388955 Keywords : micro- and mesoporous zeolites * hydroisomerization * zeolite catalysts Subject RIV: CF - Physical ; Theoretical Chemistry

  10. Mesoporous zeolite single crystal catalysts: Diffusion and catalysis in hierarchical zeolites

    DEFF Research Database (Denmark)

    Christensen, Christina Hviid; Johannsen, Kim

    2007-01-01

    During the last years, several new routes to produce zeolites with controlled mesoporosity have appeared. Moreover, an improved catalytic performance of the resulting mesoporous zeolites over conventional zeolites has been demonstrated in several reactions. In most cases, the mesoporous zeolites exhibit higher catalytic activity, but in some cases also improved selectivity and longer catalyst lifetime has been reported. The beneficial effects of introducing mesopores into the zeolites has in most instances been attributed to improved mass transport to and from the active sites located in the zeolite micropores. Here, we briefly discuss the most important ways of introducing mesopores into zeolites and, for the first time, we show experimentally that the presence of mesopores dramatically increases the rate of diffusion in zeolite catalysts. This is done by studying the elution of iso-butane from packed beds of conventional and mesoporous zeolite catalysts. Moreover, we discuss in detail the recent observationof improved activity and selectivity in the alkylation of benzene with ethene using mesoporous zeolite single crystal catalysts. For this reaction, we show by calculation of the Thiele modulus that this improved performance can be mainly attributed to a diffusional limitation of ethylbenzene in the zeolite pores. This is verified in new ethylbenzene dealkylation experiments where mesoporous zeolite catalysts show significantly improved activity over conventional zeolite catalysts.

  11. Studies on Supercapacitor Electrode Material from Activated Lignin-Derived Mesoporous Carbon

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Dipendu [ORNL; Li, Yunchao [ORNL; Bi, Zhonghe [ORNL; Chen, Jihua [ORNL; Keum, Jong Kahk [ORNL; Hensley, Dale K [ORNL; Grappe, Hippolyte A. [Oak Ridge Institute for Science and Education (ORISE); Meyer III, Harry M [ORNL; Dai, Sheng [ORNL; Paranthaman, Mariappan Parans [ORNL; Naskar, Amit K [ORNL

    2014-01-01

    We synthesized mesoporous carbon from pre-cross-linked lignin gel impregnated with a surfactant as the pore-forming agent, and then activated the carbon through physical and chemical methods to obtain activated mesoporous carbon. The activated mesoporous carbons exhibited 1.5- to 6-fold increases in porosity with a maximum BET specific surface area of 1148 m2/g and a pore volume of 1.0 cm3/g. Slow physical activation helped retain dominant mesoporosity; however, aggressive chemical activation caused some loss of the mesopore volume fraction. Plots of cyclic voltammetric data with the capacitor electrode made from these carbons showed an almost rectangular curve depicting the behavior of ideal double-layer capacitance. Although the pristine mesoporous carbon exhibited the same range of surface-area-based capacitance as that of other known carbon-based supercapacitors, activation decreased the surface-area-based specific capacitance and increased the gravimetric-specific capacitance of the mesoporous carbons. Surface activation lowered bulk density and electrical conductivity. Warburg impedance as a vertical tail in the lower frequency domain of Nyquist plots supported good supercapacitor behavior for the activated mesoporous carbons. Our work demonstrated that biomass-derived mesoporous carbon materials continue to show potential for use in specific electrochemical applications.

  12. Silica-based mesoporous nanobiomaterials as promoter of bone regeneration process.

    Science.gov (United States)

    Shadjou, Nasrin; Hasanzadeh, Mohammad

    2015-11-01

    Silica-based mesostructured nanomaterials have emerged as a full family of biomaterials with tremendous potential to address the requirements for the bone regeneration process. This review focuses on more recent advances in bone regeneration process based on silica-based mesoporous biomaterials during 2012 to January 2015. In this review, we describe application of silica-based mesoporous mesostructured nanomaterials (possessing pore sizes in the range 2-50 nm) for the bone regeneration process. We summarize the preparation methods, the effect of mesopore templates and composition on the mesopore-structure characteristics, and different forms of these materials, including particles, fibers, spheres, scaffolds, and composites. The effect of structural and textural properties of mesoporous materials on the development of new biomaterials for treatment of different bone pathologies such as infection, osteoporosis, cancer, and so forth is discussed. In addition, silica-based mesoporous bioactive glass, as a potential drug/growth factor carrier, is reviewed, which includes the composition-structure-drug delivery relationship and the functional effect on the antibacteria and tissue-stimulation properties. Also, application of different mesoporous materials on construction of 3D macroporous scaffolds for bone tissue engineering was disused. Finally, this review discusses the possibility of covalently grafting different osteoinductive agents to the silica-based mesoporous scaffold surface that act as attracting signals for bone cells to promote the bone regeneration process. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 3703-3716, 2015. PMID:26011776

  13. Surfactant-free synthesis of mesoporous and hollow silica nanoparticles with an inorganic template

    OpenAIRE

    Bau, L.; Bartova, B.; Arduini, M.; Mancin, F.

    2009-01-01

    A surfactant-free synthesis of mesoporous and hollow silica nanoparticles is reported in which boron acts as the templating agent. Using such a simple and mild procedure as a treatment with water, the boron-rich phase is selectively removed, affording mesoporous pure silica nanoparticles with wormhole-like pores or, depending on the synthetic conditions, silica nanoshells.

  14. Hydrothermal synthesis of mesoporous metal oxide arrays with enhanced properties for electrochemical energy storage

    International Nuclear Information System (INIS)

    Highlights: • NiO mesoporous nanowall arrays are prepared via hydrothermal method. • Mesoporous nanowall arrays are favorable for fast ion/electron transfer. • NiO mesoporous nanowall arrays show good supercapacitor performance. - Abstract: Mesoporous nanowall NiO arrays are prepared by a facile hydrothermal synthesis method with a following annealing process. The NiO nanowall shows continuous mesopores ranging from 5 to 10 nm and grows vertically on the substrate forming a porous net-like structure with macropores of 20–300 nm. A plausible mechanism is proposed for the growth of mesoporous nanowall NiO arrays. As cathode material of pseudocapacitors, the as-prepared mesoporous nanowall NiO arrays show good pseudocapacitive performances with a high capacitance of 600 F g?1 at 2 A g?1 and impressive high-rate capability with a specific capacitance of 338 F g?1 at 40 A g?1. In addition, the mesoporous nanowall NiO arrays possess good cycling stability. After 6000 cycles at 2 A g?1, a high capacitance of 660 F g?1 is attained, and no obvious degradation is observed. The good electrochemical performance is attributed to its highly porous morphology, which provides large reaction surface and short ion diffusion paths, leading to enhanced electrochemical properties

  15. Heavy metal recovery by a chelating resin; Recuperation de metaux lourds par une resine chelatante

    Energy Technology Data Exchange (ETDEWEB)

    Menoud, P.

    1996-12-31

    Adsorption on a chelating resin is a method to recover metals from waste water containing very small quantities of heavy metals. The usual regeneration of the resin consists of an acidic desorption of the metallic ion, an alkaline treatment of the resin and an electrolysis. A new recovering method of the metallic ion by strong complexing agents has been developed. In this case, the recovering agent is concentrated by reverse osmosis or ultrafiltration, electrolysed and then recycled at the beginning of the process. The resin used for our application is the Chelamine Standard (JPS-Chimie, Neuchatel, Switzerland). It is made of a polyacrylamide gel with tetraethylene pentamine chelating groups. Physical properties of this resin were measured. A thermodynamical study in a closed vessel showed that equilibrium was well represented by a Langmuir isotherm. These experiments stressed the influence of the resin conditioning on its equilibrium capacity: a resin regenerated in very alkaline conditions had a greater capacity than if the regenerating agent was slightly basic or neutral. Adsorption kinetics in a continuous stirred tank reactor were also conducted. Experiments were simulated by a global kinetic model comprising mass transfer in a liquid film around the resin particles, diffusion through the pores and reaction on the adsorption sites. Kinetics has been found limited by film mass transfer for all metals studied (Cu{sup 2+}, Ni{sup 2+}, Co{sup 2+} and Zn{sup 2+)}. The mass-transfer coefficient k{sub L} was found to be around 10{sup -4} ms{sup -1}. Adsorption of heavy metals was then carried out at mini-pilot scale. Problems due to a decrease in average particle diameter during the adsorption prompted us to use a fluidized bed. It is also possible with this reactor to treat solutions containing suspended solids which would clog fixed beds. (author) figs., tabs., refs.

  16. Evaluation of resins for use in brachytherapy

    International Nuclear Information System (INIS)

    Brachytherapy is an advanced cancer treatment where radioactive seeds or sources are placed near or directly into the tumor thus reducing the radiation exposure in the surrounding healthy tissues. Prostate cancer can be treated with interstitial brachytherapy in initial stage of the disease in which tiny radioactive seeds with cylindrical geometry are used. Several kinds of seeds have been developed in order to obtain a better dose distribution around them and with a lower cost manufacturing. These seeds consist of an encapsulation, a radionuclide carrier, and X-ray marker. Among the materials that have potential for innovation in the construction of seeds, biocompatible resins appear as an important option. In this paper, we present some characterization results with Fourier transform infrared spectroscopic (FTIR) and ultraviolet-visible spectroscopy (UV-vis) performed on two types of resins in which curing temperatures for each one were varied as also the results of coatings with these resins under titanium substrates. Interactions of these resins in contact with the simulated body fluid were evaluated by atomic force microscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. (author)

  17. Resin diffusion through demineralized dentin matrix

    Directory of Open Access Journals (Sweden)

    CARVALHO Ricardo M.

    1999-01-01

    Full Text Available This paper has focused on the factors that may affect the permeability of adhesive resins into the demineralized dentin matrix during the development of the bonding process. The effects of surface moisture are discussed respectively to the adhesive systems, and the problems related to incomplete hybrid layer formation presented.

  18. 21 CFR 177.1330 - Ionomeric resins.

    Science.gov (United States)

    2010-04-01

    ...containing the dried and weighed residue, e, obtained in paragraph...well so every portion of the residue is wetted with the...chloroform-soluble extractives residue, e ?. This e ? is substituted...resins that are used in food-packaging adhesives complying...

  19. Pharmaceutical Applications of Ion-Exchange Resins

    Science.gov (United States)

    Elder, David

    2005-01-01

    The historical uses of ion-exchanged resins and a summary of the basic chemical principles involved in the ion-exchanged process are discussed. Specific applications of ion-exchange are provided that include drug stabilization, pharmaceutical excipients, taste-masking agents, oral sustained-release products, topical products for local application…

  20. Evaluation of resins for use in brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Luiz Claudio F.M. Garcia; Ferraz, Wilmar Barbosa; Chrcanovic, Bruno Ramos; Santos, Ana Maria M., E-mail: ferrazw@cdtn.b, E-mail: amms@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    Brachytherapy is an advanced cancer treatment where radioactive seeds or sources are placed near or directly into the tumor thus reducing the radiation exposure in the surrounding healthy tissues. Prostate cancer can be treated with interstitial brachytherapy in initial stage of the disease in which tiny radioactive seeds with cylindrical geometry are used. Several kinds of seeds have been developed in order to obtain a better dose distribution around them and with a lower cost manufacturing. These seeds consist of an encapsulation, a radionuclide carrier, and X-ray marker. Among the materials that have potential for innovation in the construction of seeds, biocompatible resins appear as an important option. In this paper, we present some characterization results with Fourier transform infrared spectroscopic (FTIR) and ultraviolet-visible spectroscopy (UV-vis) performed on two types of resins in which curing temperatures for each one were varied as also the results of coatings with these resins under titanium substrates. Interactions of these resins in contact with the simulated body fluid were evaluated by atomic force microscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. (author)

  1. ION EXCHANGE RESINS AND THEIR APPLICATIONS

    Directory of Open Access Journals (Sweden)

    Vijay Sharma

    2014-07-01

    Full Text Available Ion exchange resins are cross-linked water insoluble polymer-carrying, ionisable functional groups. IER have received considerable attention from pharmaceutical scientists because of their versatile properties as drug delivery vehicles. Research over the last few years has revealed that IER are equally suitable for drug delivery technologies, including controlled release, transdermal, nasal, topical and taste masking. The major drawback of sustained release of extended release or extended release is dose dumping, resulting in increased risk of toxicity. The use of IER has occupied an important place in the development of controlled- or sustained-release systems because of their better drug-retaining properties and prevention of dose dumping. Synthetic ion exchange resins have been used in pharmacy and medicine for taste masking or controlled release of drug. Drug resin complexation converts drug to amorphous form leading to improved drug dissolution. Several studies have reported the use of IER for drug delivery at the desired site of action. Sulfonated and carboxylic resins with a polystyrene backbone are most widely used in clinical medicine.

  2. NITRATE CONVERSION OF HB-LINE REILLEXTM HPQ RESIN

    Energy Technology Data Exchange (ETDEWEB)

    Steimke, J.; Williams, M.; Steeper, T.; Leishear, R.

    2012-05-29

    Reillex{trademark} HPQ ion exchange resin is used by HB Line to remove plutonium from aqueous streams. Reillex{trademark} HPQ resin currently available from Vertellus Specialties LLC is a chloride ionic form, which can cause stress corrosion cracking in stainless steels. Therefore, HB Line Engineering requested that Savannah River National Laboratory (SRNL) convert resin from chloride form to nitrate form in the Engineering Development Laboratory (EDL). To perform this task, SRNL treated two batches of resin in 2012. The first batch of resin from Reilly Industries Batch 80302MA was initially treated at SRNL in 2001 to remove chloride. This batch of resin, nominally 30 liters, has been stored wet in carboys since that time until being retreated in 2012. The second batch of resin from Batch 23408 consisted of 50 kg of new resin purchased from Vertellus Specialties in 2012. Both batches were treated in a column designed to convert resin using downflow of 1.0 M sodium nitrate solution through the resin bed followed by rinsing with deionized water. Both batches were analyzed for chloride concentration, before and after treatment, using Neutron Activation Analysis (NAA). The resin specification [Werling, 2003] states the total chlorine and chloride concentration shall be less than 250 ppm. The resin condition for measuring this concentration is not specified; however, in service the resin would always be fully wet. Measurements in SRNL showed that changing from oven dry resin to fully wet resin, with liquid in the particle interstices but no supernatant, increases the total weight by a factor of at least three. Therefore, concentration of chlorine or chloride expressed as parts per million (ppm) decreases by a factor of three. Therefore, SRNL recommends measuring chlorine concentration on an oven dry basis, then dividing by three to estimate chloride concentration in the fully wet condition. Chloride concentration in the first batch (No.80302MA) was nearly the same before the current treatment (759 ppm dry) and after treatment (745 ppm dry or {approx}248 ppm wet). Treatment of the second batch of resin (No.23408) was very successful. Chloride concentration decreased from 120,000 ppm dry to an average of 44 ppm dry or {approx}15ppm wet, which easily passes the 250 ppm wet criterion. Per guidance from HB Line Engineering, SRNL blended Batch 80302 resin with Batch P9059 resin which had been treated previously by ResinTech to remove chloride. The chloride concentrations for the two drums of Batch P9059 were 248 ppm dry ({approx}83 ppm wet) {+-}22.8% and 583 ppm dry ({approx}194 ppm wet) {+-} 11.8%. The blended resin was packaged in five gallon buckets.

  3. Mesoporous metal oxide microsphere electrode compositions and their methods of making

    Science.gov (United States)

    Parans Paranthaman, Mariappan; Bi, Zhonghe; Bridges, Craig A; Brown, Gilbert M

    2014-12-16

    Compositions and methods of making are provided for treated mesoporous metal oxide microspheres electrodes. The compositions comprise (a) microspheres with an average diameter between 200 nanometers (nm) and 10 micrometers (.mu.m); (b) mesopores on the surface and interior of the microspheres, wherein the mesopores have an average diameter between 1 nm and 50 nm and the microspheres have a surface area between 50 m.sup.2/g and 500 m.sup.2/g, and wherein the composition has an electrical conductivity of at least 1.times.10.sup.-7 S/cm at 25.degree. C. and 60 MPa. The methods of making comprise forming a mesoporous metal oxide microsphere composition and treating the mesoporous metal oxide microspheres by at least one method selected from the group consisting of: (i) annealing in a reducing atmosphere, (ii) doping with an aliovalent element, and (iii) coating with a coating composition.

  4. Template Synthesis of Three-Dimensional Cubic Ordered Mesoporous Carbon With Tunable Pore Sizes

    Directory of Open Access Journals (Sweden)

    Dai Weijie

    2009-01-01

    Full Text Available Abstract Three-dimensional cubic ordered mesoporous carbons with tunable pore sizes have been synthesized by using cubic Ia3d mesoporous KIT-6 silica as the hard template and boric acid as the pore expanding agent. The prepared ordered mesoporous carbons were characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption–desorption analysis. The results show that the pore sizes of the prepared ordered mesoporous carbons with three-dimensional cubic structure can be regulated in the range of 3.9–9.4 nm. A simplified model was proposed to analyze the tailored pore sizes of the prepared ordered mesoporous carbons on the basis of the structural parameters of the silica template.

  5. Synthesis, characterization and catalytic applications in propane dehydrogenation of ordered mesoporous alumina.

    Science.gov (United States)

    Wang, Zhenzhen; Tian, Xike; Yang, Chao; Zhao, Yanxi; Pi, Zhenbang

    2009-12-01

    Alumina is the most frequently employed catalyst or catalytic support in the chemical industry. The catalytic performances of alumina-supported catalysts are largely dependent on the textural properties of the alumina supports. Therefore, any improvement of the alumina properties significant for their catalytic applications is extremely challenging. Ordered mesoporous aluminas with high thermal stability have been successfully prepared by a facile synthesis method. Using the ordered mesoporous aluminas as support, V/Ni-catalysts mesoporous materials also have been prepared by vacuum impregnation method and the coprecipitation method. The mesoporous structures are characterized by XRD, TEM, N2 adsorption -desorption and TG-DTA. Preliminary catalytic tests showed that the ordered mesoporous aluminas prepared in such a way exhibited superior performance in the oxidative dehydrogenation of propane to propylene when they were used as the supports for V and Ni catalysts. PMID:19908692

  6. Decomposition of Rare Earth Loaded Resin Particles

    International Nuclear Information System (INIS)

    The Fuel Cycle R and D (FCR and D) program within the Department of Energy Office of Nuclear Energy (DOE-NE) is evaluating nuclear fuel cycle options, including once-through, modified open, and fully closed cycles. Each of these scenarios may utilize quite different fuel management schemes and variation in fuel types may include high thermal conductivity UO2, thoria-based, TRISO, metal, advanced ceramic (nitride, carbide, composite, etc.), and minor actinide (MA) bearing fuels and targets. Researchers from the US, Europe, and japan are investigating methods of fabricating high-specific activity spherical particles for fuel and target applications. The capital, operating, and maintenance costs of such a fuel fabrication facility can be significant, thus fuel synthesis and fabrication processes that minimize waste and process losses, and require less footprint are desired. Investigations have been performed at the Institute for Transuranium Elements (ITU) and the French Atomic Energy Commission (CEA) studying the impact of americium and curium on the fuel fabrication process. proof of concept was demonstrated for fabrication of MA-bearing spherical particles, however additional development will be needed for engineering scale-up. Researchers at the Paul Scherer Institute (PSI) and the Japan Atomic Energy Association (JAEA) have collaborated on research with ceramic-metallic (CERMET) fuels using spherical particles as the ceramic component dispersed in the metal matrix. Recent work at the CEA evaluates the burning of MA in the blanket region of sodium fast reactors. There is also interest in burning MA in Canada Deuterium Uranium (CANDU) reactors. The fabrication of uranium-MA oxide pellets for a fast reactor blanket or MA-bearing fuel for CANDU reactors may benefit from a low-loss dedicated footprint for producing MA-spherical particles. One method for producing MA-bearing spherical particles is loading the actinide metal on a cation exchange resin. The AG-50W resin is made of sulfonic acid functional groups attached to a styrene divinylbenzene copolymer lattice (long chained hydrocarbon). The metal cation binds to the sulfur group, then during thermal decomposition in air the hydrocarbons will form gaseous species leaving behind a spherical metal-oxide particle. Process development for resin applications with radioactive materials is typically performed using surrogates. For americium and curium, a trivalent metal like neodymium can be used. Thermal decomposition of Nd-loaded resin in air has been studied by Hale. Process conditions were established for resin decomposition and the formation of Nd2O3 particles. The intermediate product compounds were described using x-ray diffraction (XRD) and wet chemistry. Leskela and Niinisto studied the decomposition of rare earth (RE) elements and found results consistent with Hale. Picart et al. demonstrated the viability of using a resin loading process for the fabrication of uranium-actinide mixed oxide microspheres for transmutation of minor actinides in a fast reactor. For effective transmutation of actinides, it will be desirable to extend the in-reactor burnup and minimize the number of recycles of used actinide materials. Longer burn times increases the chance of Fuel Clad Chemical or Mechanical Interaction (FCCI, FCMI). Sulfur is suspected of contributing to Irradiation Assisted Stress Corrosion Cracking (IASCC) thus it is necessary to maximize the removal of sulfur during decomposition of the resin. The present effort extends the previous work by quantifying the removal of sulfur during the decomposition process. Neodymium was selected as a surrogate for trivalent actinide metal cations. As described above Nd was dissolved in nitric acid solution then contacted with the AG-50W resin column. After washing the column, the Nd-resin particles are removed and dried. The Nd-resin, seen in Figure 1 prior to decomposition, is ready to be converted to Nd oxide microspheres.

  7. Progress of the Application of Mesoporous Silica-Supported Heteropolyacids in Heterogeneous Catalysis and Preparation of Nanostructured Metal Oxides

    Directory of Open Access Journals (Sweden)

    Heyong He

    2010-01-01

    Full Text Available Mesoporous silica molecular sieves are a kind of unique catalyst support due to their large pore size and high surface area. Several methods have been developed to immobilize heteropolyacids (HPAs inside the channels of these mesoporous silicas. The mesoporous silica-supported HPA materials have been widely used as recyclable catalysts in heterogeneous systems. They have shown high catalytic activities and shape selectivities in some reactions, compared to the parent HPAs in homogeneous systems. This review summarizes recent progress in the field of mesoporous silica-supported HPAs applied in the heterogeneous catalysis area and preparation of nanostructured metal oxides using HPAs as precursors and mesoporous silicas as hard templates.

  8. Electrochemical regeneration of spent ion exchange resin

    International Nuclear Information System (INIS)

    CAN-DECON™, CAN-DEREM™ and CAN-DEREM Plus™ processes developed by Atomic Energy of Canada Limited (AECL) are dilute regenerative chemical decontamination processes that employ ion exchange resin to remove dissolved metals and radionuclides and to regenerate the reagents. Depending on the system volume and oxide and radionuclide inventories, a large volume of spent ion exchange resin may be generated. Storage and long term disposal of spent resin may be one of the impediments to routine use of chemical decontamination processes. An electrochemical method is being developed by AECL for the regeneration of spent ion exchange resin generated during application of CAN-DECON, CAN-DEREM and CAN-DEREM Plus processes. In addition, some of the work being carried out is directed at methods for liquid waste treatment. This paper will describe the three-compartment electrochemical cell developed for laboratory tests. The cell consists of an anode, cathode and central compartment, the latter containing either solid spent resin or spent solution. The anode and the cathode compartments are separated from the central section by cation exchange membranes which allow cations to transport from anode to cathode compartments through the membranes. The paper will discuss the results of cyclic voltammetry tests performed in CAN-DEREM reagents to determine the iron redox potential in these electrolytes. The results of iron deposition tests performed in simulated spent CAN-DEREM reagents to study the current efficiency of iron deposition as a function of iron concentration, pH, cathode material and temperature will be presented. The results of tests of several commercial cation exchange membranes to study transport efficiency of iron through these membranes will also be discussed. (author)

  9. Synthesis and Characterizations of Melamine-Based Epoxy Resins

    Directory of Open Access Journals (Sweden)

    Raffaele Cioffi

    2013-09-01

    Full Text Available A new, easy and cost-effective synthetic procedure for the preparation of thermosetting melamine-based epoxy resins is reported. By this innovative synthetic method, different kinds of resins can be obtained just by mixing the reagents in the presence of a catalyst without solvent and with mild curing conditions. Two types of resins were synthesized using melamine and a glycidyl derivative (resins I or by adding a silane derivative (resin II. The resins were characterized by means of chemical-physical and thermal techniques. Experimental results show that all the prepared resins have a good thermal stability, but differ for their mechanical properties: resin I exhibits remarkable stiffness with a storage modulus value up to 830 MPa at room temperature, while lower storage moduli were found for resin II, indicating that the presence of silane groups could enhance the flexibility of these materials. The resins show a pot life higher than 30 min, which makes these resins good candidates for practical applications. The functionalization with silane terminations can be exploited in the formulation of hybrid organic-inorganic composite materials.

  10. Commercial Ion Exchange Resin Vitrification in Borosilicate Glass

    International Nuclear Information System (INIS)

    Bench-scale studies were performed to determine the feasibility of vitrification treatment of six resins representative of those used in the commercial nuclear industry. Each resin was successfully immobilized using the same proprietary borosilicate glass formulation. Waste loadings varied from 38 to 70 g of resin/100 g of glass produced depending on the particular resin, with volume reductions of 28 percent to 68 percent. The bench-scale results were used to perform a melter demonstration with one of the resins at the Clemson Environmental Technologies Laboratory (CETL). The resin used was a weakly acidic meth acrylic cation exchange resin. The vitrification process utilized represented a approximately 64 percent volume reduction. Glass characterization, radionuclide retention, offgas analyses, and system compatibility results will be discussed in this paper

  11. Effects of resins on asphaltene self-association and solubility

    Energy Technology Data Exchange (ETDEWEB)

    Yarranton, H.W.; Fox, W.A.; Svrcek, W.Y. [Calgary Univ., AB (Canada). Dept. of Chemical and Petroleum Engineering

    2007-10-15

    This paper described a method of modelling the self-association and precipitation of asphaltenes and resins. Self-association was assessed using vapor pressure osmometry (VPO) measurements of asphaltene and resin mixtures. A modified asphaltene self-association model was used to fit and interpret data. The molar mass distribution of the asphaltene-resin aggregates was characterized. Precipitation data were obtained by measuring asphaltenes and resins in solutions of asphaltenes, resins, toluene, and heptane. The molar mass distribution was then used as an input to the regular solution model. Results of the study suggested that resins participate in asphaltene self-association. It was concluded that both asphaltenes and resins are best characterized as a combined pseudo-component with a single molar mass distribution of the aggregated species. 30 refs., 4 tabs., 5 figs.

  12. ORAL CONTROLLED RELEASE METFORMIN HYDROCHLORIDE ION EXCHANGE RESINATE BEADS

    Directory of Open Access Journals (Sweden)

    Ajit S. Raghuwanshi

    2010-12-01

    Full Text Available Treating with ion exchange resin has chemically modified metformin hydrochloride to form an oral controlled release beads using ion-exchange resin sorption method. A strong cation exchange resin Amberlite IR 120 was utilized for the sorption of the drug and the drug resinates was evaluated for various physical and chemical parameters. The drug content and percentage drug release were determined spectrophotometrically at 233 nm. About 43% of drug was loaded in 4.5 h and in-vitro dissolution study showed 84% of drug release in 8 h. The drug-resinate complex was microencapsulated with a polymer Eudragit RS 100 to further retard the release characteristics. Further, the drug-resinate complex and microencapsulated drug resinate were suspended in a palatable aqueous suspension base and were evaluated for controlled release characteristic.

  13. Nano-hard template synthesis of pure mesoporous NiO and its application for streptavidin protein immobilization

    International Nuclear Information System (INIS)

    A simple and efficient immobilization of streptavidin protein (with hexa-histidine tag) onto the surface of mesoporous NiO is described. Before immobilization of streptavidin protein (with hexa-histidine tag) onto the surface of mesoporous NiO, we first synthesized well-organized mesoporous NiO by a nanocasting method using mesoporous silica SBA-15 as the hard template. Then, the well-organized mesoporous NiO particles were characterized by small angle x-ray diffraction (XRD), wide angle XRD, nitrogen adsorption/desorption, and transmission electron microscopy (TEM). TEM and small angle XRD suggested the formation of mesoporous NiO materials, whereas the wide angle XRD pattern of mesoporous NiO indicated that the nickel precursor had been transformed into crystalline NiO. The N2 sorption experiments demonstrated that the mesoporous NiO particles had a high surface area of 281 m2 g?1, a pore volume of 0.51 cm3 g?1 and a pore size of 4.8 nm. Next, the immobilization of streptavidin protein (with hexa-histidine tag) onto the surface of mesoporous NiO was studied. Detailed analysis using gel electrophoresis confirmed that this approach can efficiently bind his-tagged streptavidin onto the surface of mesoporous NiO material since the mesoporous NiO provides sufficient surface sites for the binding of streptavidin via non-covalent ligand binding with the histidine tag. (paper)

  14. Treatment of spent ion-exchange resins for disposal

    International Nuclear Information System (INIS)

    Ion-exchange resins are used in CANDU-PHW nuclear power stations to purify heavy water in the primary heat transport (PHT) and moderator systems. Two techniques for conditioning spent ion-exchange resins for disposal have been evaluated: direct immobilization, and incineration combined with immobilization of the ash and scrubbed off-gases. When ion-exchange resins were immobilized directly, no volume reductions were obtained at the various resin-to-matrix weight ratios attempted. Volumes of bitumen and glass products were equal to the volumes of untreated resin while the volumes of cement and polyester products were two and three times larger. While incinerating the resin is an extra processing step, high reductions in volume result. Bitumen and glass product volumes were six times smaller than the volumes of untreated resin while cement and polyster product volumes were about half the volume of untreated resin. Since the releases of Cs-137 were about ten times lower for products made by direct immobilization, PHT resins, which have high concentrations of Cs-137, should be immobilized directly. Moderator resins which have high concentrations of C-14 should be incinerated and the ash- and C-14-contaminated scrubbing solutions should be immobilized. By pretreating such resins with calcium chloride, the C-14 present on resin could be released at temperatures below the ignition temperature of the resin. This technique reduces the amount of inactive carbon dioxide that must be scrubbed to trap the C-14. The releases of C-14 from immobilized barium hydroxide scrubbing solution were the same as releases from immobilized resin

  15. Comparison of Mechanical Properties of Resin Composites with Resin Modified Glass Ionomers

    Directory of Open Access Journals (Sweden)

    Taha NA

    2015-06-01

    Full Text Available Statement of Problem: There are controversial reports regarding physical and mechanical properties of resin composites and glass ionomer cements. Some revealed higher strength and hardness for resin composites while others showed a comparable value for glass ionomer cements. Evaluation of mechanical properties of different types of resin composites in comparison with resin modified glass ionomers is not widely studied. Objectives: To measure and compare the flexural strength and Vickers hardness of three resin composites and two resins modified glass ionomer cements before and after ageing. Materials and Methods: Three resin composites, i.e. Filtek Supreme XTE (3M ESPE, Ice (SDI, Gradia (GC, and two resins modified glass ionomers, i.e. Fuji II LC (GC and Riva Light Cure (SDI, were selected. Ten barshaped specimens were prepared for each material and cured using LED curing light. After 24 hours storage in distilled water at 37oC, the specimens were randomly divided into two equal groups (n=5. The first group was tested as a baseline and the second group was restored at 37oC for another 29 days. Flexural strength was performed by four-point bending test using universal testing machine at crosshead speed of 0.5mm/min, and the maximum load at failure was recorded. The specimen’s halves were used for evaluating Vickers hardness, using a Digital Hardness Tester (300 g/15 sec and the Vickers hardness number (VHN was recorded. Data were analyzed using one-way analysis of variance (ANOVA, Tukey’s and student’s t-test. Results: After 24 hours of immersion, the highest hardness number was found for Filtek Supreme and Ice and the highest flexural strength was obtained for Gradia. After 30 days of storage, hardness of Fuji II LC and Gradia showed a significant decrease; flexural strength of Ice and Fuji II LC revealed a significant increase while Gradia and Filtek Supreme showed a significant decrease. Conclusions: Resin modified glass ionomers showed a comparable result for hardness and flexural strength with some of the tested resin composites and lower values than some others.

  16. Cobalt oxide and nitride particles supported on mesoporous carbons as composite electrocatalysts for dye-sensitized solar cells

    Science.gov (United States)

    Chen, Ming; Shao, Leng-Leng; Gao, Ze-Min; Ren, Tie-Zhen; Yuan, Zhong-Yong

    2015-07-01

    The composite electrocatalysts of cobalt oxide/mesoporous carbon and cobalt nitride/mesoporous carbon are synthesized via a convenient oxidation and subsequent ammonia nitridation of cobalt particles-incorporated mesoporous carbon, respectively. The cobalt oxide and nitride particles are uniformly imbedded in mesoporous carbon matrix, forming the unique composites with high surface area and mesopore architecture, and the resultant composites are evaluated as counter electrode materials, exhibiting good catalytic activity for the reduction of triiodide. The composites of cobalt nitride and mesoporous carbon are superior to the counterparts of cobalt oxide and mesoporous carbon in catalyzing the triiodide reduction, and the dye-sensitized solar cell with the composites achieves an optimum power conversion efficiency of 5.26%, which is comparable to the one based on the conventional Pt counter electrode (4.88%).

  17. Synthesis and Li-ion Insertion Properties of Highly Crystalline Mesoporous Rutile TiO2

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Donghai; Choi, Daiwon; Yang, Zhenguo; Viswanathan, Vilayanur V.; Nie, Zimin; Wang, Chong M.; Song, Yujiang; Zhang, Jiguang; Liu, Jun

    2008-05-27

    Mesoporous TiO2 has attracted great attention as a promising Li insertion electrode material with improved cycling life, rate capability and high power density. Up to date, mesoporous anatase TiO2 has been investigated for Li insertion. Recent studies have shown that nanosized rutile could be an excellent candidate for anode materials for higher Li insertion capacity and improved stability. However, synthesis of highly crystalline mesoporous rutile has met with limited success so far. There has been no report on Li insertion of mesoporous rutile TiO2. In this paper, we report a new low-temperature solution growth of TiO2 nanocrystals within an anionic surfactant matrix to produce highly crystalline mesoporous rutile and investigate Li insertion properties of the mesoporous crystalline rutile. X-ray diffraction (XRD) patterns and N2 sorption isotherms reveal mesoporous structure in the highly crystalline mesoporous TiO2 directly results from the anionic surfactant templating effects with high surface area (245~300 m2/g) and tunable mesopore diameter ranging from 2.2 to 3.8 nm after calcination. Transmission electron microscopy (TEM) measurements show that framework of the highly crystalline mesoporous TiO2 are composed of aligned rutile nanorod building blocks grown along [001] direction. The new mesoporous crystalline rutile can accommodate more than 0.7 Li (Li0.7TiO2, 235 mAh/g) during the first discharge at C/5 rate between 1–3 V versus Li+/Li, with a reversible capacity of 0.55 Li (Li0.55TiO2, 185 mAh/g). The mesoporous crystalline rutile shows excellent capacity retention with less than 10% capacity loss after over 100 cycles. XRD and TEM characterization on electrochemically lithiated sample show that the rutile nanorods were transformed into cubic rocksalt LiTiO2 nanorods, but the mesostructures remained stable after the phase transformation and cycling. Furthermore, the crystalline mesoporous rutile may also have good potentials for other applications such as stable catalyst supports.

  18. Use of an adhesive resin for bonding orthodontic brackets.

    Science.gov (United States)

    Ireland, A J; Sherriff, M

    1994-02-01

    To date, most successful bonding agents used in orthodontics rely on mechanical retention to both the enamel and bracket base. Chemical adhesion to enamel as seen with glass ionomer cements, and to the silanated base of ceramic brackets have been tried. Recent developments in resin formulation have led to the production of adhesive diacrylate resins capable of forming adhesive bonds to certain metals including stainless steel. The aim of this experiment was to compare such a resin, Panavia EX, with a more conventional 'no-mix' orthodontic bonding resin. Two different base retention mechanisms were used, and the effect of rebonding and differing environmental conditions were also investigated. The results indicated that Panavia EX could produce greater bond strengths than the more conventional bonding resin. Of the two base retention systems tested, braised mesh bases gave consistently greater bond strengths than the cast base, although no base/resin specificity could be detected. Re-using the same brackets showed rebound strengths to be significantly lower than initial bond strength although the results indicated the adhesive resin was still able to bond more effectively to these used brackets than the conventional resin. Environment had the greatest effect on bond strength, such that following environmental exposure there was no significant difference between the two resins. This latter factor, and in particular the more complex bonding technique required for the adhesive resin, means that Panavia EX cannot be recommended for orthodontic use in its present form. PMID:8181547

  19. Handling sticky resin by stingless bees (Hymenoptera, Apidae

    Directory of Open Access Journals (Sweden)

    Markus Gastauer

    2011-06-01

    Full Text Available For their nest defense, stingless bees (Meliponini collect plant resins which they stick on intruders like ants or cleptobiotic robber bees causing their immobilization. The aim of this article is to identify all parts of stingless bee workers contacting these sticky resins. Of special interest are those body parts with anti-adhesive properties to resin, where it can be removed without residues. For that, extensive behavioral observations during foraging flight, handling and application of the resin have been carried out. When handling the resin, all tarsi touch the resin while walking above it. For transportation from plants to the nest during foraging flight, the resin is packed to the corbicula via tarsi and basitarsi of front and middle legs. Once stuck to the resin or after the corbicula had been unloaded, the bee's legs have to be cleaned thoroughly. Only the tips of the mandibles, that form, cut and apply the sticky resin, seem to have at least temporarily resin-rejecting properties.

  20. Evaluation of the resin oxidation process using Fenton's reagent

    International Nuclear Information System (INIS)

    The ion exchange resin is considered radioactive waste after its final useful life in nuclear reactors. Usually, this type of waste is treated with the immobilization in cement Portland, in order to form a solid monolithic matrix, reducing the possibility of radionuclides release in to environment. Because of the characteristic of expansion and contraction of the resins in presence of water, its incorporation in the common Portland cement is limited in 10% in direct immobilization, causing high costs in the final product. A pre-treatment would be able to reduce the volume, degrading the resins and increasing the load capacity of this material. This paper is about a method of degradation of ion spent resins from the nuclear research reactor of Nuclear and Energy Research Institute (IPEN/CNEN-SP), Brazil, using the Fenton's reagent. The resin evaluated was a mixture of cationic and anionic resins. The reactions were conducted by varying the concentration of the catalyst (25 to 80 mM), with and without external heat. The time of reaction was two hours. The concentration of 50 mM of catalyst was the most effective in degrading approximately 99%. The resin degradation was confirmed by the presence of CaCO3 as a white precipitate resulting from the reaction between the Ca(OH)2 and the CO2 from the resin degradation. It was possible to degrade the resins without external heating. The calcium carbonates showed no correlation with the residual resin mass. (author)

  1. Petroleum Resins: Separation, Character, and Role in Petroleum

    DEFF Research Database (Denmark)

    Andersen, Simon Ivar; Speight, James

    2001-01-01

    In petroleum science, the term resin generally implies material that has been eluted from various solid adsorbents, whereas the term maltenes (or petrolenes) indicates a mixture of the resins and oils obtained as filtrates from the asphaltene precipitation. Thus, after the asphaltenes are precipitated, adsorbents are added to the n-pentane solutions of the resins and oils, by which process the resins are adsorbed and subsequently recovered by the use of a more polar solvent, and the oils remain in solution. The resin fraction plays an important role in the stability of petroleum and prevents separation of the asphaltene constituents as a separate phase. Indeed, the absence of the resin fraction (produced by a variety of methods) from the maltenes influences the ability of the de-resined maltenes to accommodate the asphaltenes either in solution or as a stable part of a colloidal system. In spite of the fact that the resin fraction is extremely important to the stability of petroleum, there is surprisingly little work reported on the characteristics of the resins. This article summarizes the work that has been carried out in determining the character and properties of the resin constituents. Suggestions are also made regarding current thoughts of the role of these constituents on the structure and stability of petroleum.

  2. Contribution to the study of the formation mechanism of ordered porous carbons from a soft-template method using the copolymer triblock (PEO140PPO39PEO140) and a phenolic resin

    Scientific Electronic Library Online (English)

    Cristiam F., Santa; Ligia, Sierra.

    2011-12-01

    Full Text Available Diferentes carbonos porosos foram sintetizados empregando automontagem direta de um surfactante non-iônico (PEO140PPO39PEO140 (Pluronic®), PEO poli(óxido de etileno) e PPO poli(óxido de propileno)) e uma resina fenólica. Segundo experimentos de espalhamento de luz dinâmico (DLS) realizados antes da [...] floculação, a formação de micelas híbridas cobertas (precursores de materiais mesoporosos ordenados) compete com a formação de partículas resol dependendo da concentração do surfactante. Elevada temperatura de síntese aumenta a formação de mesoporosidade. Quando monômeros (ao invés de oligômeros) são usados como precursores de resina, a mesoporosidade também é aumentada. Porém neste caso, a formação de partículas resol também é favorecida. Os materiais obtidos são principalmente microporosos, indicando que polímeros/micelas híbridas surfactantes não são estáveis o suficiente para modelar a formação de carbonos altamente mesoporosos. A interação apropriada entre micelas surfactantes e espécies precursoras de resinas, assim como o grau de polimerização da resina, é crucial para a obtenção de polímeros/micelas híbridas surfactantes que conduzam à formação de carbonos mesoporosos. Abstract in english Different porous carbons were synthesized using direct self-assembly of a nonionic surfactant (PEO140PPO39PEO140, PEO poly(ethylene oxide) and PPO poly(propylene oxide)) and a phenolic resin. According to dynamic light scattering (DLS) experiments realized before the flocculation, the formation of c [...] overed hybrid micelles (precursors of ordered mesoporous materials) competes with the formation of resol particles depending on the surfactant concentration. High synthesis temperature increases the formation of mesoporosity. When monomers (instead of oligomers) are used as resin precursors, the mesoporosity is also enhanced. However in this case, the formation of resol particles is also favored. The obtained materials are mainly microporous, indicating that the formed polymer/surfactant hybrid micelles are not stable enough to template the formation of highly mesoporous carbons. Appropriate interaction between the surfactant micelles and resin precursor species, as well as the polymerization degree of the resin, is crucial for obtaining polymer/surfactant hybrid micelles that conduce to mesoporous carbons.

  3. Anion-exchange resin-based desulfurization process. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sheth, A C; Dharmapurikar, R; Strevel, S D

    1994-01-01

    The following investigations were performed: (1) batch mode screening of eleven(11) commercially available resins and selection of three candidate resins for further evaluation in a fixed-bed setup. (2) Process variables study using three candidate resins in the fixed-bed setup and selection of the ``best`` resin for process economics development. (3) Exhaustion efficiency and solution concentration were found to be inversely related necessitating a trade-off between the resin cost versus the cost of evaporation/concentration of ensuing effluents. (4) Higher concentration of the HCO{sub 3}{sup {minus}} form of active sites over less active CO{sub 3}{sup 2{minus}} form of sites in the resin was believed to be the main reason for the observed increase in the equilibrium capacity of the resin at an elevated static CO{sub 2}-pressure. This Increase in capacity was found to level off around 80--120 psig range. The increase in CO{sub 2}-pressure, however, did not appear to affect the overall ion-exchange kinetics. (5) In the fixed-bed mode, the solution concentration was found to affect the equilibrium capacity of candidate resins. Their relationship was well satisfied by the Langmuir type non-linear equilibrium isotherm. Alternatively, the effect of solution concentration on overall ion-exchange kinetics varied from resin to resin. (6) Product inhibition effect on the resin was observed as an initial increase followed by a significant decrease in the resin`s equilibrium capacity for SO{sub 4}{sup 2{minus}} as the HCO{sub 3}{sup {minus}}/SO{sub 4}{sup 2{minus}} molar ratio in the solution was increased from 0 to 1.0. This ratio, however, did not affect the overall ion-exchange kinetics.

  4. Mesoporous silica nanoparticles for biomedical and catalytical applications

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xiaoxing

    2011-05-15

    Mesoporous silica materials, discovered in 1992 by the Mobile Oil Corporation, have received considerable attention in the chemical industry due to their superior textual properties such as high surface area, large pore volume, tunable pore diameter, and narrow pore size distribution. Among those materials, MCM-41, referred to Mobile Composition of Matter NO. 41, contains honeycomb liked porous structure that is the most common mesoporous molecular sieve studied. Applications of MCM-41 type mesoporous silica material in biomedical field as well as catalytical field have been developed and discussed in this thesis. The unique features of mesoporous silica nanoparticles were utilized for the design of delivery system for multiple biomolecules as described in chapter 2. We loaded luciferin into the hexagonal channels of MSN and capped the pore ends with gold nanoparticles to prevent premature release. Luciferase was adsorbed onto the outer surface of the MSN. Both the MSN and the gold nanoparticles were protected by poly-ethylene glycol to minimize nonspecific interaction of luciferase and keep it from denaturating. Controlled release of luciferin was triggered within the cells and the enzymatic reaction was detected by a luminometer. Further developments by varying enzyme/substrate pairs may provide opportunities to control cell behavior and manipulate intracellular reactions. MSN was also served as a noble metal catalyst support due to its large surface area and its stability with active metals. We prepared MSN with pore diameter of 10 nm (LP10-MSN) which can facilitate mass transfer. And we successfully synthesized an organo silane, 2,2'-Bipyridine-amide-triethoxylsilane (Bpy-amide-TES). Then we were able to functionalize LP10-MSN with bipyridinyl group by both post-grafting method and co-condensation method. Future research of this material would be platinum complexation. This Pt (II) complex catalyst has been reported for a C-H bond activation reaction as an alternative of the traditional Friedel-Crafts reaction. And we will compare the turnover numbers of MSN supported material with homogenous catalyst to evaluate the catalytical efficiency of our material.

  5. Synthesis and in vitro bioactivity of mesoporous bioactive glass scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Shih, C.J., E-mail: cjshih@kmu.edu.tw [Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chen, H.T. [Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Huang, L.F. [School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Lu, P.S.; Chang, H.F. [Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chang, I.L., E-mail: 84004@cch.org.tw [Department of Orthopaedic Surgery, Chang-Hua Christian Hospital, Changhua 500, Taiwan (China)

    2010-06-15

    The main objective of the present study was to determine the effect of thermal treatment procedures (calcination temperature, heating rate and duration time) on the synthesis of SiO{sub 2}-CaO-P{sub 2}O{sub 5} mesoporous bioactive glass scaffolds. This is accomplished by thermogravimetric analyses, Fourier transform infrared (FTIR) absorption spectra, X-ray diffraction (XRD) and by analysis of nitrogen adsorption/desorption isotherms. In vitro bioactivity can also be assessed by the cytotoxic effect of the glasses on the NIH-3T3 cell line, and by characterization of MC-3T3-E1 cell attachment.

  6. SBA-15 mesoporous silica as a super insulating material

    Science.gov (United States)

    Belmoujahid, Y.; Bonne, M.; Scudeller, Y.; Schleich, D.; Grohens, Y.; Lebeau, B.

    2015-07-01

    The thermal insulation behavior of ordered mesoporous silica SBA-15 aggregates heat treated at 300 ?C was studied. An important decrease in the effective thermal conductivity according to the increase of the apparent density was observed. A thermal conductivity value less than 25 mW.m-1.K-1 was reached during the compaction phenomenon. Results of thermal conductivity were correlated to the electron microscopy observations and physicochemical data (X-ray diffraction, adsorption/desorption of nitrogen volumetric measurements). These thermal properties make these materials very promising for thermal insulation applications, especially with values inferior to the thermal conductivity of air.

  7. Synthesis and in vitro bioactivity of mesoporous bioactive glass scaffolds

    International Nuclear Information System (INIS)

    The main objective of the present study was to determine the effect of thermal treatment procedures (calcination temperature, heating rate and duration time) on the synthesis of SiO2-CaO-P2O5 mesoporous bioactive glass scaffolds. This is accomplished by thermogravimetric analyses, Fourier transform infrared (FTIR) absorption spectra, X-ray diffraction (XRD) and by analysis of nitrogen adsorption/desorption isotherms. In vitro bioactivity can also be assessed by the cytotoxic effect of the glasses on the NIH-3T3 cell line, and by characterization of MC-3T3-E1 cell attachment.

  8. Dealuminated Mesoporous Silica-Alumina as Carrier for Pt Catalysts.

    Czech Academy of Sciences Publication Activity Database

    Gulková, Daniela; Vít, Zden?k; Kaluža, Lud?k; Zdražil, Miroslav

    Messina : Samperi Editore - Messina, 2009 - (Perathoner, S.; Quartieri, S.; Casella, A.), P10-1-P10-2 ISBN 978-88-86038-58-4. [Czech-Italian-Spanish Trilateral Meeting on Catalysis and Micro/Meso-Porous Materials /3./. Acireale,Sicily (IT), 21.06.2009-25.06.2009] R&D Projects: GA ?R GA104/09/0751 Institutional research plan: CEZ:AV0Z40720504 Keywords : mesoporous silica-aluminas * catalysts * dealumination Subject RIV: CC - Organic Chemistry

  9. Modification of mesoporous silica surface applied as drug delivery system

    International Nuclear Information System (INIS)

    A mesoporous silica with ordered cubic structure, SBA16, was chemically modified with different alcoxisilanos using solvents with different solubility parameters (methanol and toluene), to evaluate its effectiveness as a matrix for the controlled delivery of atenolol. The structural characteristics of the material were evaluated by small angle XRD, N2 adsorption and scanning electron microscopy. The degree of functionalization of the matrix was evaluated using techniques of FTIR, thermal analysis and elemental analysis CHN. It was found that the type of solvent influences the degree of functionalization and this significantly affects the release process. (author)

  10. Hybrid Photonic Antennae Based on Mesoporous Silica Frameworks

    Directory of Open Access Journals (Sweden)

    Cucinotta F.

    2013-09-01

    Full Text Available This contribution describes design, preparation and physico-chemical characterization of a new photostable hybrid antenna based on mesoporous SBA-15 silica. Concepts of host-guest chemistry are applied in such a way that one or more photoactive guest molecules are incorporated into the silica channels and on the outer surface, acting as energy harvesting and transferring units. The presented composite system behaves as efficient Förster resonance energy transfer (FRET pair and shows high photoluminescence and stability towards photodegradation, representing an important step forward in the search for new efficient materials with opto-electronic applications.

  11. Thermal and hydrothermal stability of ZrMCM-41 mesoporous molecular sieves obtained by microwave irradiation

    Indian Academy of Sciences (India)

    T S Jiang; Y H Li; X P Zhou; Q Zhao; H B Yin

    2010-05-01

    ZrMCM-41 mesoporous molecular sieves were synthesized by using the zirconium sulfate as zirconium source and using cetyltrimethyl ammonium bromide as a template under microwave irradiation condition. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), inductive coupled plasma (ICP) technique, Fourier transform infrared spectroscopy (FT-IR) and N2 physical adsorption, respectively. The effect of the different initial ZrO2 : SiO2 molar ratio, the different thermal treatment temperature and hydrothermal treatment time on textural property was investigated. The results show that the obtained products possess a typical mesoporous structure of MCM-41 and have specific surface areas in the range of $598.1 \\sim 971.4$ m2/g and average pore sizes in the range of ca. $2.46 \\sim 3.43$ nm. On the other hand, the BET specific surface area and pore volume of the synthesized ZrMCM-41 mesoporous molecular sieve decrease with the increased amount of zirconium incorporated in the starting material, the rise of thermal treatment temperature and the prolonging of hydrothermal treatment time, the mesoporous ordering deteriorates. The mesoporous structure of the ZrMCM-41 mesoporous molecular sieve still retains after calcination at 750°C for 3 h or hydrothermal treatment at 100°C for 6 days, however, the mesoporous ordering is poor.

  12. High-pressure synthesis of mesoporous stishovite: potential applications in mineral physics

    Science.gov (United States)

    Stagno, Vincenzo; Mandal, Manik; Landskron, Kai; Fei, Yingwei

    2015-06-01

    Recently, we have described a successful synthesis route to obtain mesoporous quartz and its high-pressure polymorph coesite by nanocasting at high pressure using periodic mesostructured precursors, such as SBA-16 and FDU-12/carbon composite as starting materials. Periodic mesoporous high-pressure silica polymorphs are of particular interest as they combine transport properties and physical properties such as hardness that potentially enable the industrial use of these materials. In addition, synthesis of mesoporous crystalline silica phases can allow more detailed geology-related studies such as water/mineral interaction, dissolution/crystallization rate and the surface contribution to the associated thermodynamic stability (free energy and enthalpy) of the various polymorphs and their crossover. Here, we present results of synthesis of mesoporous stishovite from cubic large-pore periodic mesoporous silica LP-FDU-12/C composite as precursor with an fcc lattice. We describe the synthesis procedure using multi-anvil apparatus at 9 GPa (about 90,000 atm) and temperature of 500 °C. The synthetic mesoporous stishovite is, then, characterized by wide and small-angle X-ray diffraction, scanning/transmission electron microscopy and gas adsorption. Results show that this new material is characterized by accessible mesopores with wide pore size distribution, surface area of ~45 m2/g and volume of pores of ~0.15 cm3/g. Results from gas adsorption indicate that both porosity and permeability are retained at the high pressures of synthesis but with weak periodic order of the pores.

  13. Hierarchical zeolites: progress on synthesis and characterization of mesoporous zeolite single crystal catalysts

    DEFF Research Database (Denmark)

    Kustova, Marina; Egeblad, Kresten

    2007-01-01

    Recently, a new family of crystalline zeolitic materials was reported, the so-called mesoporous zeolite single crystals featuring individual zeolite single crystals with an additional noncrystalline mesopore system interconnected with the usual micropore system of the zeolite, resulting in a hierarchical pore size distribution. In this work, the preparation of mesoporous ZSM-12 single crystal catalysts using a new improved procedure for directly introducing carbon in the reaction mixture is reported. The microwave heating technique is also applied for the synthesis of mesoporous silicalite-1 single crystals using this direct introduction of carbon into the reaction mixture. All samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), temperature-programmed desorption of ammonia (NH3-TPD), and N-2 adsorption measurements. Additionally, the results of diffusion of n-hexadecane in conventional and mesoporous zeolites are presented. Isomerization and cracking of n-hexadecane was chosen as model test reaction for these materials. All results support that mesoporous zeolites are superior catalysts due to improved mass transport. Importantly, the mesoporous zeolites show significant improved resistance to poisoning by carbon formation.

  14. Structure of heat-treated mesoporous carbon and its electrochemical lithium intercalation behavior

    International Nuclear Information System (INIS)

    Mesoporous carbon (MPC) was synthesized via the thermal decomposition of magnesium citrate in a flow of Ar gas, followed by dissolution of MgO nanoparticles in the carbonaceous pyrolysis product. The MPC was then heated at 1800, 2000, 2200, 2400, 2500, 2700 and 3000 °C for 30 min. The MPC samples heated at 1800 and 2000 °C having a mesopore structure with graphitized carbon walls exhibited an enhanced rate capability as a composite anode for lithium ion batteries. Heat treatment of the MPC from 2200 to 2700 °C led to a partial collapse of micropores and mesopores, which decreased the charge/discharge capacity. The MPC samples heated at 2700 and 3000 °C having thick graphitized carbon layers and a mesopore structure with graphitized carbon walls showed charge/discharge curves with three lithium intercalation potential plateaus at approximately 0.2, 1.0, and 1.5 V vs. Li/Li+. The MPC sample heated at 3000 °C was the best anode material for lithium ion batteries among the MPC samples evaluated in this study because of its low irreversible capacity, high columbic efficiency, and high rate capability. - Highlights: • Mesoporous carbon was heated in the temperature range between 1800 °C and 3000 °C. • The growth of hexagonal carbon layers occurred in the mesopore carbon walls. • Electrochemical lithium intercalation behavior was investigated for the graphitized mesoporous carbon

  15. Immobilization of spent resins with polymers

    International Nuclear Information System (INIS)

    This report describes the processes for immobilization of spent resins generated from NPPs with polymers in which styrene and polyester have been investigated. The results obtained show that both styrene and polyester system processes are feasible to solidify spent resins by means of dewatering or drying if necessary. The performance, such as mechanical strength, leaching rates, thermal stability and radiation resistance etc, of the solidified forms with styrene and polyester can meet the requirements of storage, transportation and final disposal. Though the styrene system process may have a maximum loading capacity of as high as 65 wt%, which is more than that of polyester system, and a little cheaper cost, the polyester system possesses its own advantages, such as no special requirement of solidification temperature, relative short period of solidification needed and lower leaching rates and cumulative fractions. (author). 10 refs, 3 figs, 10 tabs

  16. Integrating Porous Resins In Enzymatic Processes

    DEFF Research Database (Denmark)

    Al-Haque, Naweed

    2012-01-01

    Increasing pressure mandated by different government policies, for developing sustainable chemical processes for the synthesis of optically pure compounds, has resulted in increased considerations of biocatalysis as a viable option by many industries. Biocatalysis, with its exquisite selective properties and potential ‘green’ attributes, presents it as a sustainable alternative. Today, the role of biocatalysis is most evident in the pharmaceutical industry and is currently extending towards fine and bulk chemical production as well. The use of hydrolytic enzymes (lipases) is well established in several chemical industries, though certain challenges persist in other types of enzymes (transferases and ketoreductases), thus limiting their implementation in industry. Inhibition by substrate and product as well as low aqueous solubility of substrates has constrained the full potential of these enzymes to be harnessed. Porous resins as opposed to other auxiliary phases, for example organic solvents, are nonbioavailable, biocompatible and offer simpler operational handling (no foaming and emulsification). This strategy has been applied effectively to single substrate – single product systems (oxidation, V microbial degradation and hydrolysis). However, this concept has not been extended to other industrially relevant reactions which are two substrate – two product systems. In this thesis, a methodological framework has been successfully developed to aid in implementing the strategy of integrating porous resins for multi-component systems. In this manner, a generic platform has been established for biocatalytic reactions that require the integration of this strategy. The framework identifies the key information about the reaction and the process using a step-wise protocol with the required tools. It includes the use of kinetic modelling in characterizing the reaction kinetics, a heuristic approach for screening resins and a model based approach for evaluating the process. Greater knowledge about the enzymatic processes with integrated porous resins can therefore be gained and thus the efficiency of process development with respect to time and resources required (reduced number of experiments) could be increased. Estimating kinetic model parameters for enzymatic reactions is quite complex and frequently leads to identifiability issues. In order to understand the different techniques to estimate the parameters, a number of concepts are discussed in chapter four of this thesis. This knowledge has contributed to the development of a robust methodology for the estimation of kinetic model parameters for biocatalytic reactions, which has also been published in a peer reviewed journal. Screening resins for moderately hydrophobic multi-component systems is challenging. Often it is found that the capacity of the resin is inversely related with product selectivity. Therefore a tradeoff has to be made between these parameters which can be crucial from an economic point of view. A low resin capacity points towards the need for higher resin loading, which in turn determines the equilibrium concentration of the substrate in the reactor and the type of reactor that can be used (stirred tank reactor or packed bed reactor). Similarly low product selectivity would result in higher product concentration in the reactor and thus not aid in alleviating inhibition. Further considerationsProcess modelling is a very effective tool in evaluating a process. Critical information about the process can be gained by means of simulations, which can further be re-used to tune the reaction or process conditions to harness the full potential of the enzyme. State-of-the-art mathematical techniques for model quality evaluation, such as uncertainty and sensitivity analysis, have been included in this analysis in order to identify the key model parameters for better understanding of the process. Three case studies were used to illustrate the applicability of the methodology to fulfil different objective requirements. The case studies were selected for not only

  17. Nuclear magnetic resonance in furfuryl alcohol resins

    International Nuclear Information System (INIS)

    Broad line and pulsed nuclear magnetic resonance studies are carried out on a number of furfuryl alcohol resins differentiated by viscosity. Proton NMR spectra and relaxation times T1 and Tsub(1p) are measured over a wide temperature range and the results are interpreted in terms of molecular motion. The marked decrease in second moment and existence of high temperature spin-lattice relaxation times minima are presumed to result from rotational motion of polymer chains. Distinct differences in activation energies derived from the slope of the logarithm of T1 versus the inverse temperature and from known values of correlation times at T1 and Tsub(1p) minima indicate the existence of a distribution of correlation times of this motion. The width of the distribution function for the resins investigated was found. The relaxation processes at low temperature are believed to be due to rotational motion of methyl endgroup and paramagnetic centres. (author)

  18. Development of a Heterogeneous Laminating Resin

    Science.gov (United States)

    Gosnell, R.

    1984-01-01

    The feasibility of toughening the common types of matrix resins such as Narmco 5208 by utilizing a heterogeneous additive was examined. Some basic concepts and principles in the toughening of matrix resins for advanced composites were studied. The following conclusions were advanced: (1) the use of damage volume as a guide for measurement of impact resistance appears to be a valid determination; (2) short beam shear is a good test to determine the effect of toughening agents on mechanical properties; (3) rubber toughening results in improved laminate impact strength, but with substantial loss in high temperature dry and wet strength; (4) in the all-epoxy systems, the polycarbonate toughening agent seemed to be the most effective, although hot-wet strength is sacrificed; ABS was not as effective; and (5) in general, the toughened all-epoxy systems showed better damage tolerance, but less hot-wet strength; toughened bismaleimides had better hot-wet strength.

  19. Ionization radiation curable polyacrylate resin coatings

    International Nuclear Information System (INIS)

    A carboxylic acid chloride or bromide, a sulfonyl chloride or bromide, cyanuric chloride, calcium hypochlorite or phosphorus oxychloride and optionally a buffering pigment are combined with a liquid, acrylate ester resin curable by exposure to high-energy ionizing radiation to yield a coating composition which upon being cured in air by exposure to ionizing radition yields a coating having an essentially tack-free surface. (Patent Office Record)

  20. Microbial lipase production on a polymeric resin

    OpenAIRE

    Christen, Pierre; Angeles, N.; G. Corzo; Farres, A.; S. Revah

    1995-01-01

    #Rhizopus delemar$ was grown in a submerged culture and produced a lipase at 14 U/ml. It was compared with solid state fermentation with a polymeric resin (Amberlite). The lipase was produced and simultaneously adsorbed on the support : 96 U/g initial dry matter were obtained when dextrin was used as the carbon source against only 68 and 58 U/g for maltose and glucose, respectively. (Résumé d'auteur)

  1. Cellulose whisker/epoxy resin nanocomposites

    OpenAIRE

    Tang, Liming; Weder, Christoph

    2010-01-01

    New nanocomposites composed of cellulose nanofibers or “whiskers” and an epoxy resin were prepared. Cellulose whiskers with aspect ratios of ?10 and ?84 were isolated from cotton and sea animals called tunicates, respectively. Suspensions of these whiskers in dimethylformamide were combined with an oligomeric difunctional diglycidyl ether of bisphenol A with an epoxide equivalent weight of 185?192 and a diethyl toluenediamine-based curing agent. Thin films were produced by casting these mixtu...

  2. Modelling and monitoring of resin transfer moulding

    OpenAIRE

    Skordos, Alexandros A.

    2000-01-01

    Modelling and monitoring tools appropriate for the resin transfer moulding composites manufacturing route were developed in this study. A simulation of the curing stage of the process based on a finite elements solution of the non-linear heat conduction equation was implemented. The simulation involved appropriate submodels for the incorporation of thermal properties and cure kinetics. A novel non-parametric procedure which utilises interpolation applied directly to experimenta...

  3. ION EXCHANGE RESINS AND THEIR APPLICATIONS

    OpenAIRE

    Vijay Sharma

    2014-01-01

    Ion exchange resins are cross-linked water insoluble polymer-carrying, ionisable functional groups. IER have received considerable attention from pharmaceutical scientists because of their versatile properties as drug delivery vehicles. Research over the last few years has revealed that IER are equally suitable for drug delivery technologies, including controlled release, transdermal, nasal, topical and taste masking. The major drawback of sustained release of extended release or extended rel...

  4. Composite fabrication via resin transfer molding technology

    Energy Technology Data Exchange (ETDEWEB)

    Jamison, G.M.; Domeier, L.A.

    1996-04-01

    The IMPReS (Integrated Modeling and Processing of Resin-based Structures) Program was funded in FY95 to consolidate, evaluate and enhance Sandia`s capabilities in the design and fabrication of composite structures. A key driver of this and related programs was the need for more agile product development processes and for model based design and fabrication tools across all of Sandia`s material technologies. A team of polymer, composite and modeling personnel was assembled to benchmark Sandia`s existing expertise in this area relative to industrial and academic programs and to initiate the tasks required to meet Sandia`s future needs. RTM (Resin Transfer Molding) was selected as the focus composite fabrication technology due to its versatility and growing use in industry. Modeling efforts focused on the prediction of composite mechanical properties and failure/damage mechanisms and also on the uncured resin flow processes typical of RTM. Appropriate molds and test composites were fabricated and model validation studies begun. This report summarizes and archives the modeling and fabrication studies carried out under IMPReS and evaluates the status of composite technology within Sandia. It should provide a complete and convenient baseline for future composite technology efforts within Sandia.

  5. Resinas quelantes amidoxímicas / Amidoxime chelating resins

    Scientific Electronic Library Online (English)

    Fernanda M. B., Coutinho; Simone M., Rezende; Celina C. R., Barbosa.

    1999-12-01

    Full Text Available Resinas quelantes com grupos amidoxima foram sintetizadas por copolimerização em suspensão de acrilonitrila (AN) e divinilbenzeno (DVB) e subsequente modificação química dos grupos ciano por reação com hidroxilamina. Na copolimerização, a proporção de divinilbenzeno e o grau de diluição foram variad [...] os. Gelatina e carbonato de cálcio foram usados como estabilizadores de suspensão e sulfato de sódio foi adicionado para reduzir a solubilidade da acrilonitrila em água, por meio do efeito salting out. Os copolímeros de AN/DVB e as resinas amidoxímicas obtidos foram caracterizados por meio de densidade aparente, área específica, volume de poros e teor de nitrogênio. As resinas amidoxímicas foram também avaliadas em relação a capacidade de complexação de íons cobre. Abstract in english Chelating resins with amidoxime groups were synthesized by suspension copolymerization of acrylonitrile (AN) and divinylbenzene (DVB) and subsequent chemical modification of cyano groups by reaction with hydroxylamine. In the copolymerization, the proportion of divinylbenzene and the dilution degree [...] were varied. Gelatin and calcium carbonate were used as suspension stabilizers and sodium sulphate was added in order to reduce acrylonitrile solubility in water, by salting out effect. The AN/DVB copolymers and amidoxime resins obtained were characterized by apparent density, surface area, pore volume and by the content of nitrogen. The amidoxime resins were also evaluated in relation to the complexation capacity of copper ion.

  6. Resinas quelantes amidoxímicas Amidoxime chelating resins

    Directory of Open Access Journals (Sweden)

    Fernanda M. B. Coutinho

    1999-12-01

    Full Text Available Resinas quelantes com grupos amidoxima foram sintetizadas por copolimerização em suspensão de acrilonitrila (AN e divinilbenzeno (DVB e subsequente modificação química dos grupos ciano por reação com hidroxilamina. Na copolimerização, a proporção de divinilbenzeno e o grau de diluição foram variados. Gelatina e carbonato de cálcio foram usados como estabilizadores de suspensão e sulfato de sódio foi adicionado para reduzir a solubilidade da acrilonitrila em água, por meio do efeito salting out. Os copolímeros de AN/DVB e as resinas amidoxímicas obtidos foram caracterizados por meio de densidade aparente, área específica, volume de poros e teor de nitrogênio. As resinas amidoxímicas foram também avaliadas em relação a capacidade de complexação de íons cobre.Chelating resins with amidoxime groups were synthesized by suspension copolymerization of acrylonitrile (AN and divinylbenzene (DVB and subsequent chemical modification of cyano groups by reaction with hydroxylamine. In the copolymerization, the proportion of divinylbenzene and the dilution degree were varied. Gelatin and calcium carbonate were used as suspension stabilizers and sodium sulphate was added in order to reduce acrylonitrile solubility in water, by salting out effect. The AN/DVB copolymers and amidoxime resins obtained were characterized by apparent density, surface area, pore volume and by the content of nitrogen. The amidoxime resins were also evaluated in relation to the complexation capacity of copper ion.

  7. Thermal stability of ion-exchange resins

    International Nuclear Information System (INIS)

    The action of heat, radiation and oxidants on carbonchain polymers, such as ion-exchange resins, often cause irreversible chemical changes in macro molecules. These changes can be e g the rupture of the carbon-carbon single or double bond, and/or the degradation of the macro molecule. Ion-exchange materials also contain the far less stable bonds between functional groups and the polymer matrix. For this reason the thermal stability of ion-exchange mat- erials is mainly based on the behaviour of the functional groups, which are responsible for the ion-exchange. The solidification of the ion-exchange resin waste usually involves elevated tempera- tures. Bituminization is carried out at 130-160 degrees C. Cementa- tion is carried out at room temperature. However, cementation can generate temperatures of up to 100-120 degrees C in the solidifica- tion product during the curing period. In this study the swelling/ shrinking properties of different ion-exchange materials have been studied in air and water as a function of the drying time and temp- erature. The air dried resins were used as the reference material. The effect of sodium sulphate as a possible additive to reduce swelling was studied, The experiments which were performed and re- sults observed are discussed in detail in the Appendices. (Authors)

  8. Characterization Of Cycled Spherical Resorcinol-Formaldehyde Ion Exchange Resin

    International Nuclear Information System (INIS)

    This report presents characterization data for two spherical resorcinol-formaldehyde (sRF) resin beds that had processed cesium in non-radioactive and radioactive cycles. All column cycle operations for the resin beds including loading, displacements, elution, regeneration, breakthroughs, and solution analyses are reported in Nash and Duignan, 2009a. That report covered four ion exchange (IX) campaigns using the two ?11 mL beds in columns in a lead-lag arrangement. The first two campaigns used Savannah River Site (SRS) Tank 2F nonradioactive simulant while the latter two were fed with actual dissolved salt in the Savannah River National Laboratory (SRNL) Shielded Cells. Both radioactive cycles ran to cesium breakthrough of the lead column. The resin beds saw in excess of 400 bed volumes of feed in each cycle. Resin disposal plans in tank farm processing depend on characterizations of resin used with actual tank feed. Following a final 30 bed volume (BV) elution with nitric acid, the resin beds were found to contain detectable chromium, barium, boron, aluminum, iron, sodium, sulfur, plutonium, cesium, and mercury. Resin affinity for plutonium is important in criticality safety considerations. Cesium-137 was found to be less than 10E+7 dpm/g of resin, similar to past work with sRF resin. Sulfur levels are reasonably consistent with other work and are expected to represent sulfur chemistry used in the resin manufacture. There were low but detectable levels of technetium, americium, and curium. Toxicity Characteristic Leaching Procedure (TCLP) work on the used (eluted) resin samples showed significant contents of mercury, barium, and chromium. One resin sample exceeded the TCLP level for mercury while the other metals were below TCLP levels. TCLP organics measurements indicated measurable benzene in one case, though the source was unknown. Results of this work were compared with other work on similar sRF resin characterizations in this report. This is the first work to quantify mercury on sRF resin. Resin mercury content is important in plans for the disposition of used sRF resin. Mercury speciation in high level waste (HLW) is unknown. It may be partly organic, one example being methyl mercury cation. Further study of the resin's affinity for mercury is recommended.

  9. CHARACTERIZATION OF CYCLED SPHERICAL RESORCINOL-FORMALDEHYDE ION EXCHANGE RESIN

    Energy Technology Data Exchange (ETDEWEB)

    Nash, C.; Duignan, M.

    2010-02-23

    This report presents characterization data for two spherical resorcinol-formaldehyde (sRF) resin beds that had processed cesium in non-radioactive and radioactive cycles. All column cycle operations for the resin beds including loading, displacements, elution, regeneration, breakthroughs, and solution analyses are reported in Nash and Duignan, 2009a. That report covered four ion exchange (IX) campaigns using the two {approx}11 mL beds in columns in a lead-lag arrangement. The first two campaigns used Savannah River Site (SRS) Tank 2F nonradioactive simulant while the latter two were fed with actual dissolved salt in the Savannah River National Laboratory (SRNL) Shielded Cells. Both radioactive cycles ran to cesium breakthrough of the lead column. The resin beds saw in excess of 400 bed volumes of feed in each cycle. Resin disposal plans in tank farm processing depend on characterizations of resin used with actual tank feed. Following a final 30 bed volume (BV) elution with nitric acid, the resin beds were found to contain detectable chromium, barium, boron, aluminum, iron, sodium, sulfur, plutonium, cesium, and mercury. Resin affinity for plutonium is important in criticality safety considerations. Cesium-137 was found to be less than 10E+7 dpm/g of resin, similar to past work with sRF resin. Sulfur levels are reasonably consistent with other work and are expected to represent sulfur chemistry used in the resin manufacture. There were low but detectable levels of technetium, americium, and curium. Toxicity Characteristic Leaching Procedure (TCLP) work on the used (eluted) resin samples showed significant contents of mercury, barium, and chromium. One resin sample exceeded the TCLP level for mercury while the other metals were below TCLP levels. TCLP organics measurements indicated measurable benzene in one case, though the source was unknown. Results of this work were compared with other work on similar sRF resin characterizations in this report. This is the first work to quantify mercury on sRF resin. Resin mercury content is important in plans for the disposition of used sRF resin. Mercury speciation in high level waste (HLW) is unknown. It may be partly organic, one example being methyl mercury cation. Further study of the resin's affinity for mercury is recommended.

  10. Effects of layering technique on the shade of resin overlays and the microhardness of dual cure resin cement

    Scientific Electronic Library Online (English)

    Hoon-Sang, Chang; Sung-Ok, Hong.

    2014-06-11

    Full Text Available The purpose of this study was to assess the color of layered resin overlays and to test the early microhardness of dual cure resin cement (DCRC) light cured through the layered resin overlays. Resin overlays of 1.5 mm thickness were fabricated with the A3 shade of Z350 (Group 1L), the A3B and A3E sh [...] ades of Supreme XT (Group 2L), and the A3, E3, and T1 shades of Sinfony (Group 3L) using one, two, and three layers, respectively (n = 7). Each layer of the resin overlays was set in equal thickness. The color of the resin overlays was measured with a colorimeter and compared with an A3 shade resin denture tooth. DCRC was light cured through the resin overlays, and the early microhardness of the DCRC was measured. The ?E value between the denture tooth and the resin overlays and the Vickers hardness number (VHN) of the DCRC were analyzed with one-way ANOVA and Tukey’s HSD test. The color differences were 8.9 ± 0.5, 5.3 ± 1.0, and 7.3 ± 0.5 and the VHNs were 19.4 ± 1.1, 21.1 ± 0.9, and 29.3 ± 0.6 for Groups 1L, 2L, and 3L, respectively. Therefore, to match the designated tooth color of resin inlays and to increase the early microhardness of DCRC, layered resin inlays are more appropriate than single-dentin-layer resin inlays. However, the translucent layer should be used cautiously because the color difference of resin inlays with a translucent layer was affected more than those without a translucent layer.

  11. Highly ordered magnetic mesoporous silicas for effective elimination of carbon monoxide

    Science.gov (United States)

    Lee, Jiho; Ho Chang, Jeong

    2012-04-01

    Catalysts based on crystalline nanoparticles of Fe metal supported on mesoporous silica have been developed. The synthetic process involves hydrogen reduction processing for high abundant Fe metal nanoparticles within the mesopores, in which impregnated Fe salt in the inner nanopores of mesoporous silica is thermally treated under hydrogen at 500 °C. Detailed characterization was achieved by XRD, XPS, BET, and HR-TEM techniques. The catalytic efficiency was demonstrated as a function of the used amounts and reaction time. The results show that more than 90% of the carbon monoxide was eliminated at room temperature during a period 80 min with 0.5 g of catalyst.

  12. Hot resin supercompaction. The development through the years

    Energy Technology Data Exchange (ETDEWEB)

    Fehrmann, Henning [Westinghouse Electric Germany GmbH, Mannheim (Germany)

    2014-04-15

    The Hot Resin Supercompaction (HRSC) is a thermal spent resin treatment process which is installed in several Nuclear Power Plants (NPP). The first installation was in the mid 1990 at NPP Philipsburg (Germany), followed by NPP Tihange (Belgium) in 2008 and NPP Sanmen (China) in 2013. Characteristically the HRSC process provides completely dry spent resin and final waste products that are volume reduced and contained in so called pellets. The pellets themselves are qualified waste products according to German repository requirements which enable flexible handling. Through the years development was carried out to adapt the HRSC process from its first application with a mixture of powder and bead resins to treatment of pure bead resins. Up to now the HRSC process is successfully used in the operational phase for spent resin treatment. Its application for the post operation and decommissioning phase is a valid option as the integrated Supercompactor can be used for other waste streams resulting out of decommissioning. (orig.)

  13. Kinetic study of ion exchange in phosphoric acid chelating resin

    International Nuclear Information System (INIS)

    Uranium may be recovered as a by product of wet phosphoric acid using a method based on specific ion exchange resins. These resins called chelates contain amino-phosphonic functional groups. The resin studied in this work is a purolite S-940; uranium may be loaded on this resin from 30% P2O5 phosphoric acid in its reduced state. The influence of different parameters on the successive steps of the process have been studied in batch experiments: uranium reduction, loading and oxydation. Uranium may be eluted with ammonium carbonate and the resin regeneration may be done with hydrochloric acid.Ferric ions reduce the effective resin capacity considerably and inert fixation conditions are proposed to enhance uranium loading

  14. Design of systems for handling radioactive ion exchange resin beads

    International Nuclear Information System (INIS)

    The flow of slurries in pipes is a complex phenomenon. There are little slurry data available on which to base the design of systems for radioactive ion exchange resin beads and, as a result, the designs vary markedly in operating plants. With several plants on-line, the opportunity now exists to evaluate the designs of systems handling high activity spent resin beads. Results of testing at Robbins and Meyers Pump Division to quantify the behavior of resin bead slurries are presented. These tests evaluated the following slurry parameters; resin slurry velocity, pressure drop, bead degradation, and slurry concentration effects. A discussion of the general characteristics of resin bead slurries is presented along with a correlation to enable the designer to establish the proper flowrate for a given slurry composition and flow regime as a function of line size. Guidelines to follow in designing a resin handling system are presented

  15. Solidification of ion exchange resin wastes in hydraulic cement

    International Nuclear Information System (INIS)

    Work has been conducted to investigate the solidification of ion exchange resin wastes with portland cements. These efforts have been directed toward the development of acceptable formulations for the solidification of ion exchange resin wastes and the characterization of the resultant waste forms. This paper describes formulation development work and defines acceptable formulations in terms of ternary phase compositional diagrams. The effects of cement type, resin type, resin loading, waste/cement ratio and water/cement ratio are described. The leachability of unsolidified and solidified resin waste forms and its relationship to full-scale waste form behavior is discussed. Gamma irradiation was found to improve waste form integrity, apparently as a result of increased resin crosslinking. Modifications to improve waste form integrity are described. 3 tables

  16. Fiber reinforced silicon-containing arylacetylene resin composites

    Directory of Open Access Journals (Sweden)

    2007-12-01

    Full Text Available A silicon-containing arylacetylene resin (SAR, a poly(dimethylsilyleneethynylene phenyleneethynylene (PMSEPE, was synthesized. The PMSEPE is a solid resin at ambient temperature with a softening temperature about 60°C and soluble in some solvents like tetrahydrofuran. The melt viscosity of the PMSEPE resin is less than 1 Pa•s. The resin could cure at the temperature of lower than 200°C. Fiber reinforced PMSEPE composites were prepared from prepregs which were made by the impregnation of fibers in PMSEPE resin solution. The composites exhibit good mechanical properties at room temperature and 250°C. The observation on fracture surfaces of the composites reinforced by glass fibers and carbon fibers demonstrates that the adhesion between the fibers and resin is good. The results from an oxyacetylene flame test show that the composites have good ablation performance and XRD analyses indicate that SiC forms in the residues during the ablation of the composites.

  17. Physical properties of ZnO base and resin cements.

    Science.gov (United States)

    Bapna, M S

    1980-01-01

    Some physical properties of zinc phosphate, zinc polycarboxylate, and a resin cement of thick consistency suitable for cementation of orthodontic bands were evaluated. A new technique for evaluating the setting time is described. The setting times for resin and zinc polycarboxylate cements were about the same but less than that for zinc phosphate. The properties of percent solubility and compressive strength were significantly superior for resin cement. PMID:6928356

  18. Analytical applications of resins containing amide and polyamine functional groups

    International Nuclear Information System (INIS)

    A dibutyl amide resin is used for the separation of uranium(VI), thorium(IV), and zirconium(IV) from each other and several other metal ions. Uranium(VI) and thorium(IV) are determined in the presence of large excesses of foreign metal ions and anions. A practical application of the amide resin is studied by determining uranium in low grade uranium ores. The amide resin is also used for the selective concentration of gold(III) from sea water

  19. Attribute based selection of thermoplastic resin for vacuum infusion process

    DEFF Research Database (Denmark)

    Prabhakaran, R.T. Durai; Lystrup, Aage; Løgstrup Andersen, Tom

    2011-01-01

    The composite industry looks toward a new material system (resins) based on thermoplastic polymers for the vacuum infusion process, similar to the infusion process using thermosetting polymers. A large number of thermoplastics are available in the market with a variety of properties suitable for different engineering applications, and few of those are available in a not yet polymerised form suitable for resin infusion. The proper selection of a new resin system among these thermoplastic polymers...

  20. Internal stabilization of polycarbonate resins by two stage radiation process

    Science.gov (United States)

    Gupta, Amitava (Inventor); Liang, Ranty H. (Inventor); Yavrouian, Andre H. (Inventor)

    1988-01-01

    A new polycarbonate copolymer resin is formed by internal generation of stabilizers bound to the polymer chain. Irradiation of a solid piece or a deoxygenated solution of the resin at a first frequency below 300 nm generates 2 to 8 mol percent of phenyl salicylate groups which are rearranged to dihydroxybenzophenone groups by irradiating the resin under oxygen excluding conditions at a second frequency from 300 to 320 nm.

  1. Control of swelling of the hydrophilic amidoxime chelating resin

    International Nuclear Information System (INIS)

    We have been making a study on the physicochemical properties of the amidoxime type chelating resins to enhance the rate of uranium adsorption per volume. Amidoxime resins crosslinked with both TEGDM and DVB were synthesized. Their adsorptive properties of uranium from sea water were examined. The resin, which was crosslinked with 13 wt% TEGDM and 27 wt% DVB, showed the highest uranium adsorption rate per volume from sea water. (author)

  2. Enhancement of Elastic Modulus of Epoxy Resin with Carbon Nanotubes

    OpenAIRE

    Vijay Kumar Srivastava

    2011-01-01

    Nanocomposites consisting of multiwall carbon nanotubes (MWCNT) and epoxy resin were produced by a standard calendaring technique. In this study, 3% multiwall carbon nanotube particles were dispersed in epoxy resin by weight to produce the multiwall carbon nanotubes/epoxy composite. Nanohardness and Raman spectroscopy tests were used to obtain the modulus of elasticity and Raman intensity of MWCNTs/ epoxy resin composite. The results show that the Raman intensity increased with the increase o...

  3. Block containing contaminated ion exchange resins and preparation process

    International Nuclear Information System (INIS)

    The invention concerns a block containing contaminated ion exchange resins for storage in a repository. Ion exchange resins are incorporated, after water saturation, in a composite matrix made of hardened epoxide resin and cement chosen among Clinker slag cements and slag-ashes cements. The presence of cement in composite matrix allows to limit the temperature in such block below 63 degree C, during their preparation

  4. A tool for increasing the lifetime of chromatography resins

    OpenAIRE

    Grönberg, Anna; Eriksson, Malin; Ersoy, Maria; Johansson, Hans J

    2011-01-01

    There is a steadily increasing demand for speed, cost efficiency and process understanding within biopharmaceutical process development. To match this, a high-throughput method for screening of cleaning-in-place (CIP) conditions for chromatography resins has been developed. The methodology includes fouling of MabSelect SuRe chromatography resin in 96-well filter plates, cleaning of the fouled resin by incubation in different CIP agents, and finally, analysis of the residual impurities on the ...

  5. Monitoring the Cure State of Thermosetting Resins by Ultrasound

    OpenAIRE

    Alfonso Maffezzoli; Francesca Lionetto

    2013-01-01

    The propagation of low intensity ultrasound in a curing resin, acting as a high frequency oscillatory excitation, has been recently proposed as an ultrasonic dynamic mechanical analysis (UDMA) for cure monitoring. The technique measures sound velocity and attenuation, which are very sensitive to changes in the viscoelastic characteristics of the curing resin, since the velocity is related to the resin storage modulus and density, while the attenuation is related to the energy dissipation and ...

  6. Mesoporous Phosphate Heterostructures: Synthesis and Application on Adsorption and Catalysis

    Science.gov (United States)

    Moreno-Tost, Ramón; Jiménez-Jiménez, José; Infantes-Molina, Antonia; Cavalcante, Celio L.; Azevedo, Diana C. S.; Soriano, María Dolores; López Nieto, José Manuel; Jiménez-López, Antonio; Rodríguez-Castellón, Enrique

    Porous phosphate heterostructures (PPHs) are solids formed by a layered metal(IV) phosphate expanded with silica galleries obtained by combining the two main strategies for obtaining mesoporous materials [pillared layered structures (PLS') and MCM-41]. The different synthetic pathways for obtaining mesoporous phosphate structures with silica galleries with Zr- or Ti-doped silica, the study of their structural, textural and acid properties, its functionalisation with different organic substances such as propionitrile, 3-aminopropyl triethoxysilane, (3-mercaptopropyl)trimethoxysilane, vinyltrimethoxysilane, phenyltriethoxysilane and 3-(triethoxysilyl)propionitrile are discussed. The preparation of metal-supported catalysts and their application in gas separation, adsorption and catalysis are reviewed. Specifically, the use of Cu- and Fe-exchanged PPH for the adsorption of benzothiophene and the separation of propane/propene is the main application as adsorbent. The hydrotreating of aromatic hydrocarbons using ruthenium-impregnated catalysts via hydrogenation and hydrogenolysis/hydrocracking for the production of clean diesel fuels, the selective catalytic reduction of NO from stationary and mobile sources by using Cu-PPH with 1, 3 and 7 wt% of Cu and the selective oxidation of hydrogen sulphide to sulphur with vanadium-containing PPH are the three catalytic reactions of environmental interest studied.

  7. pH-Dependent Selective Protein Adsorption into Mesoporous Silica

    CERN Document Server

    Moerz, Sebastian T

    2015-01-01

    The adsorption of lysozyme, cytochrome c and myoglobin, similar-sized globular proteins of approximately 1.5 nm radius, into the mesoporous silica material Santa Barbara Amorphous-15 (SBA-15) with 3.3 nm mean pore radius has been studied photometrically for aqueous solutions containing a single protein type and for binary protein mixtures. Distinct variations in the absolute and relative adsorption behavior are observed as a function of the solution's pH-value, and thus pore wall and protein charge. The proteins exhibit the strongest binding below their isoelectric points pI, which indicates the dominance of electrostatic interactions between charged amino acid residues and the -OH groups of the silica surface in the mesopore adsorption process. Moreover, we find for competitive adsorption in the restricted, tubular pore geometry that the protein type which shows the favoured binding to the pore wall can entirely suppress the adsorption of the species with lower binding affinity, even though the latter would ...

  8. Periodic mesoporous organosilica with a hexagonally pillared lamellar structure.

    Science.gov (United States)

    Lee, Hyung Ik; Kim, Ji Man; Stucky, Galen D

    2009-10-14

    Ordered mesoporous materials (OMMs) with well-defined pore sizes (>2 nm) and pore geometries are important in various applications that require fast mass transfer or deal with large molecules. Extensive research has resulted in the discovery of OMMs with three types of mesostructures: (i) bi- or multicontinuous, (ii) columnar, and (iii) discontinuous (cagelike). However, another type, the pillared lamellar structure, which has long been sought and has been mathematically computed and known to exist in the research fields of surfactant and multiblock-copolymer mesophases, still remains a mesostructure that has not been observed in real OMMs for any specific symmetry. Herein, we report an unprecedented type of ordered mesoporous material with a hexagonally pillared lamellar (HPL) structure (P6(3)/mmc) that can be synthesized via a phase transformation from a lamellar mesophase by hydrothermal reaction in the presence of an organosilica precursor and a high concentration of a designed Gemini surfactant (Gem(16-3-16)) that has a large g value. The present GMO-HPL, which has an unique three-dimensional periodic structure with two-dimensionally connected pore channels running between the framework layers, provides a fascinating topological link between the lamellar and columnar (2D hexagonal) mesophases. It is unique in its application potential by making possible selective 2D diffusion in different directions. PMID:19754125

  9. Dipolar rotors orderly aligned in mesoporous fluorinated organosilica architectures

    KAUST Repository

    Bracco, Silvia

    2015-02-16

    New mesoporous covalent frameworks, based on hybrid fluorinated organosilicas, were prepared to realize a periodic architecture of fast molecular rotors containing dynamic dipoles in their structure. The mobile elements, designed on the basis of fluorinated p-divinylbenzene moieties, were integrated into the robust covalent structure through siloxane bonds, and showed not only the rapid dynamics of the aromatic rings (ca. 108 Hz at 325 K), as detected by solid-state NMR spectroscopy, but also a dielectric response typical of a fast dipole reorientation under the stimuli of an applied electric field. Furthermore, the mesochannels are open and accessible to diffusing in gas molecules, and rotor mobility could be individually regulated by I2 vapors. The iodine enters the channels of the periodic structure and reacts with the pivotal double bonds of the divinyl-fluoro-phenylene rotors, affecting their motion and the dielectric properties. Oriented molecular rotors: Fluorinated molecular rotors (see picture) were engineered in mesoporous hybrid organosilica architectures with crystalline order in their walls. The rotor dynamics was established by magic angle spinning NMR and dielectric measurements, indicating a rotational correlation time as short as 10-9 s at 325 K. The dynamics was modulated by I2 vapors entering the pores.

  10. The role of curvature in silica mesoporous crystals

    KAUST Repository

    Miyasaka, Keiichi

    2012-02-08

    Silica mesoporous crystals (SMCs) offer a unique opportunity to study micellar mesophases. Replication of non-equilibrium mesophases into porous silica structures allows the characterization of surfactant phases under a variety of chemical and physical perturbations, through methods not typically accessible to liquid crystal chemists. A poignant example is the use of electron microscopy and crystallography, as discussed herein, for the purpose of determining the fundamental role of amphiphile curvature, namely mean curvature and Gaussian curvature, which have been extensively studied in various fields such as polymer, liquid crystal, biological membrane, etc. The present work aims to highlight some current studies devoted to the interface curvature on SMCs, in which electron microscopy and electron crystallography (EC) are used to understand the geometry of silica wall surface in bicontinuous and cage-type mesostructures through the investigation of electrostatic potential maps. Additionally, we show that by altering the synthesis conditions during the preparation of SMCs, it is possible to isolate particles during micellar mesophase transformations in the cubic bicontinuous system, allowing us to view and study epitaxial relations under the specific synthesis conditions. By studying the relationship between mesoporous structure, interface curvature and micellar mesophases using electron microscopy and EC, we hope to bring new insights into the formation mechanism of these unique materials but also contribute a new way of understanding periodic liquid crystal systems. © 2012 The Royal Society.

  11. Mesoporous aluminosilicate ropes with improved stability from protozeolitic nanoclusters

    International Nuclear Information System (INIS)

    Mesoporous aluminosilicate ropes with improved hydrothermal stability have been prepared through S+X-I+ route via self-assembly of protozeolitic nanoclusters with cetyltrimethylammonium bromides (CTAB) template micelles in HNO3 solution. SEM observation confirmed that high-yield aluminosilicate ropes could be produced under proper HNO3 concentration. NO3- ions had strong binding strength to the CTA+ ions and tended to form more elongated surfactant micelles, thus fibrous products were fabricated under the direction of these long rod micelles in shearing flow. At the same time, the NO3- ions combining with CTA+ ions generated more active (CTA+NO3-) assembly, which effectively catalysed the polymerization of protozeolitic nanoclusters with large volume into highly ordered mesostructures. Compared with normal MCM-41 silica synthesized through S+X-I+ route in acidic media, the hydrothermal stability was improved considerably. These protozeolitic nanoclusters survived strongly acidic media and entered into mesostructured framework, which contributed to the improvement of hydrothermal stability. - Graphical abstract: Mesoporous aluminosilicate ropes with enhanced hydrothermal stability were fabricated from protozeolitic nanoclusters through S+X-I+ route in HNO3 solution under the direction of CTAB templates

  12. Synthesis and textural evolution of alumina particles with mesoporous structures

    International Nuclear Information System (INIS)

    Alumina particles with mesostructures were synthesized through a chemical precipitation method by using different inorganic aluminum salts followed by a heterogeneous azeotropic distillation and calcination process. The obtained mesoporous ?-alumina particles were systematically characterized by the X-ray diffraction, transmission electron microscopy and nitrogen adsorption-desorption measurement. Effects of the aluminum salt counter anion, pH value and the azeotropic distillation process on the structural or textural evolution of alumina particles were investigated. It is found that Cl- in the reaction solution can restrain the textural evolution of the resultant precipitates into two-dimensional crystallized pseudoboehmite lamellae during the heterogeneous azeotropic distillation, and then transformed into ?-Al2O3 particles with mesostructures after further calcination at 1173 K, whereas coexisting SO42- can promote above morphology evolution and then transformed into ?-Al2O3 nanofibers after calcination at 1173 K. Moreover nearly all materials retain relatively high specific surface areas larger than 100 m2 g-1 even after calcinations at 1173 K. - Graphical abstract: Co-existing Cl- is beneficial for the formation of ?-alumina nanoparticles with mesostructures during the precipitation process. Interparticle and intraparticle mesopores can be derived from acidic solution and near neutral solution, respectively.

  13. New cement solidification technique of ion-exchange resin to improve resin content and leachability

    International Nuclear Information System (INIS)

    A high performance cement, which consists of slag cement, reinforcing fiber and acid clay, has been developed to solidify spent ion-exchange resin. The cement had the following features as compared with the conventional one: 1) Tensile strength of the cement was almost doubled by adding fiber. This enabled resin content in a waste form to be increased, hence reducing the number of waste packages to about half. 2) The acid clay adsorbed radioactive nuclides in the waste from, hence reducing its leachability to about 1/10

  14. Adsorption Characteristics of Copper (II) onto Ferrocene Modified Resin

    OpenAIRE

    Qian Wang; Senlin Tian; Zongliang He; Jiaqi Li; Ping Ning

    2013-01-01

    Ferrocene (Fc) modified cation exchange resin (FMCER) was synthesized for copper adsorption process and characterized by XRF and BET analysis. Fc has been successfully impregnated into resin, and Fc loaded on resin was about 0.1792% (w/w). Both surface area and pore width of resin was enlarged. Results from batch experiments indicated that the adsorption kinetics of Cu2+ obeyed pseudo-second-order kinetic model and the adsorption rate constant was 0.0011 g/mg/min. Langmuir adsorption isotherm...

  15. Retrofitting Trojan Nuclear Plant's spent resin transfer system

    International Nuclear Information System (INIS)

    The spent resin slurry transport system at the Trojan Nuclear Plant operated by Portland General Electric Company is one of the most advanced systems of its type in the nuclear industry today. The new system affords the plant's operators safe remote sonic indication for spent resin and cover water levels, manual remote dewatering and watering capability to establish desirable resin-to-water volumetric ratios, reliable non-mechanical resin agitation utilizing fixed spargers, and controllable process flow utilizing a variable speed recessed impeller pump

  16. Treatment method for stabilization of radioactive exchange resin

    International Nuclear Information System (INIS)

    This is a method for eluting radioactive nuclides from a radioactive ion exchange resin in which it has been absorbed. First, the Cs in this resin is extracted using a neutral salt solution which contains Na+. The Cs that has been transferred to the neutral salt solution is absorbed and expelled by inorganic ion exchangers. Then the Co, Fe, Mn and Sr in said resin are eluted using an acidic solution; the Co, Fe, Mn and Sr that have been transferred to the acidic solution are separated from that solution by means of a diffusion dialysis vat. This process is a unique characteristic of this ion exchange resin treatment method. 1 fig

  17. Studies on palladium recovery using poly (4-vinylpyridine) resins

    International Nuclear Information System (INIS)

    Three cross-linked (4, 8 and 12%) gel-type weak-base poly(4-vinylpyridine) (PVP) resins were studied for the recovery of palladium from nitric acid medium. Sorption of palladium decreases with an increase in cross-linkage of the resin. Weak-base PVP resins exhibited high DPd(II) values compared to Dowex 1x8. Addition of chloride ions enhances palladium extraction. The selective recovery of palladium was achieved from the simulated HLLW solution using 8% PVP resin at 4M HNO3. (author)

  18. Studies on extraction of uranium by sulphonated phosphinic acid resin

    International Nuclear Information System (INIS)

    The extraction of Uranium from high active waste is essential for effective waste management. Conventional cation exchanger will not suit for this purpose as the medium will have higher acidity. In this work sulphonated phosphinic acid resin was evaluated for its suitability to use it in high acidity medium. Extraction coefficient of this resin for uranium was obtained at different acidity and its performance was compared with other resins. The result obtained indicate that this resin is more probable candidate to use in high acid medium. (author)

  19. Development of heat resistant ion exchange resin. First Report

    International Nuclear Information System (INIS)

    In nuclear power stations, as a means of maintaining the soundness of nuclear reactors, the cleaning of reactor cooling water has been carried out. But as for the ion exchange resin which is used as the cleaning agent in the filtrating and desalting facility in reactor water cleaning system, since the heat resistance is low, high temperature reactor water is cooled once and cleaned, therefore large heat loss occurs. If the cleaning can be done at higher temperature, the reduction of heat loss and compact cleaning facilities become possible. In this study, a new ion exchange resin having superior heat resistance has been developed, and the results of the test of evaluating the performance of the developed ion exchange resin are reported. The heat loss in reactor water cleaning system, the heat deterioration of conventional ion exchange resin, and the development of the anion exchange resin of alkyl spacer type are described. The outline of the performance evaluation test, the experimental method, and the results of the heat resistance, ion exchange characteristics and so on of C4 resin are reported. The with standable temperature of the developed anion exchange resin was estimated as 80 - 90degC. The ion exchange performance at 95degC of this resin did not change from that at low temperature in chloride ions and silica, and was equivalent to that of existing anion exchange resin. (K.I.)

  20. Modified ion exchange resins - synthesis and properties. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Doescher, F.; Klein, J.; Pohl, F.; Widdecke, H.

    1982-01-22

    Sulfomethylated resins are prepared by polymer analogous reactions, starting from macroporous poly(styrene-co-divinylbenzene) matrices. Different reaction paths are discussed and used in the synthesis. Sulfomethylation can be achieved by reaction of a chloromethylated resin with dimethyl sulfide and sodium sulfonate or alternatively by oxidation of polymer-bound thiol groups. Both methods give high conversions as shown by IR spectra and titration of the sulfonic acid groups. Poly(1-(4-hydroxysulfomethylphenyl)ethylene) (3) is obtained by reaction of poly(1-(4-hydroxyphenyl)ethylene) (2) resin with formaldehyde/sodium sulfonate. The thermal stability, catalytic activity, and ion exchange equilibria of the sulfomethylated resin are investigated.

  1. Extraction of uranium by macroporous bifunctional phosphinic acid resin

    International Nuclear Information System (INIS)

    The extraction of U(VI), Th(IV) and a number of fission products from nitric acid medium by a newly synthesised macroporous bifunctional phosphinic acid resin has been studied. The extraction of uranium from sulphuric acid medium has also been studied. While the gel type phosphinic acid resins seems to pose a number of problems in practical applications, the macroporous type resins are shown to be suitable for a variety of applications where conventional ion exchange resins are of limited use. 12 refs., 5 figs., 3 tabs

  2. A tool for increasing the lifetime of chromatography resins.

    Science.gov (United States)

    Grönberg, Anna; Eriksson, Malin; Ersoy, Maria; Johansson, Hans J

    2011-01-01

    There is a steadily increasing demand for speed, cost efficiency, and process understanding within biopharmaceutical process development. To match this, a high-throughput method for screening of cleaning-in-place (CIP) conditions for chromatography resins has been developed. The methodology includes fouling of MabSelect SuRe chromatography resin in 96-well filter plates, cleaning of the fouled resin by incubation in different CIP agents, and finally, analysis of the residual impurities on the resin after cleaning. This article describes the improvements that transformed the method from low throughput and significant manual interference to a totally automated method with high throughput and good reproducibility. PMID:21304272

  3. A Comparison of Shear Bond Strength of Ceramic and Resin Denture Teeth on Different Acrylic Resin Bases

    OpenAIRE

    Corsalini, Massimo; Venere, Daniela Di; Pettini, Francesco; Stefanachi, Gianluca; Catapano, Santo; Boccaccio, Antonio; Lamberti, Luciano; Pappalettere, Carmine; CAROSSA, Stefano

    2014-01-01

    The purpose of this study is to compare the shear bond strength of different resin bases and artificial teeth made of ceramic or acrylic resin materials and whether tooth-base interface may be treated with aluminium oxide sandblasting. Experimental measurements were carried on 80 specimens consisting of a cylinder of acrylic resin into which a single tooth is inserted. An ad hoc metallic frame was realized to measure the shear bond strength at the tooth-base interface. A complete factorial...

  4. A Study on Effect of Surface Treatments on the Shear Bond Strength between Composite Resin and Acrylic Resin Denture Teeth

    OpenAIRE

    Chatterjee, Nirmalya; Gupta, Tapas K.; Banerjee, Ardhendu

    2011-01-01

    Visible light-cured composite resins have become popular in prosthetic dentistry for the replacement of fractured/debonded denture teeth, making composite denture teeth on partial denture metal frameworks, esthetic modification of denture teeth to harmonize with the characteristics of adjacent natural teeth, remodelling of worn occlusal surfaces of posterior denture teeth etc. However, the researches published on the bond strength between VLC composite resins and acrylic resin denture teeth i...

  5. 21 CFR 177.1900 - Urea-formaldehyde resins in molded articles.

    Science.gov (United States)

    2010-04-01

    ...true Urea-formaldehyde resins in molded...177.1900 Food and Drugs ...Repeated Use Food Contact Surfaces...1900 Urea-formaldehyde resins in molded...articles. Urea-formaldehyde resins may be safely used as the food-contact...

  6. 77 FR 16508 - National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins...

    Science.gov (United States)

    2012-03-21

    ...Hazardous Air Pollutant Emissions: Group IV Polymers and Resins; Pesticide Active Ingredient...Hazardous Air Pollutant Emissions: Group IV Polymers and Resins; National Emission Standards...Hazardous Air Pollutant Emissions: Group IV Polymers and Resins; Pesticide Active...

  7. 49 CFR 173.173 - Paint, paint-related material, adhesives, ink and resins.

    Science.gov (United States)

    2010-10-01

    ...Paint, paint-related material, adhesives, ink and resins. 173.173 Section 173...paint-related material, adhesives, ink and resins. (a) When the § 172...paint-related material, adhesives, ink and resins must be packaged as...

  8. 77 FR 31875 - Certain Rubber Resins and Processes for Manufacturing Same; Notice of Receipt of Complaint...

    Science.gov (United States)

    2012-05-30

    ...COMMISSION [Docket No. 2897] Certain Rubber Resins and Processes for Manufacturing...received a complaint entitled Certain Rubber Resins and Processes for Manufacturing...United States after importation of certain rubber resins and processes for...

  9. 77 FR 38083 - Certain Rubber Resins and Processes for Manufacturing Same Institution of Investigation Pursuant...

    Science.gov (United States)

    2012-06-26

    ...Investigation No. 337-TA-849] Certain Rubber Resins and Processes for Manufacturing...United States after importation of certain rubber resins and processes for manufacturing...United States after importation of certain rubber resins and processes for...

  10. Self-assembly synthesis of hollow mesoporous silica nanoparticles assisted by macromolecule polymer

    International Nuclear Information System (INIS)

    A novel 'macromolecule assisted' strategy has been developed to fabricate hollow spherical mesoporous silica nanoparticles by Using macromolecules to assist the spontaneous organization of templates and inorganic silicates into structurally ordered nanoscale architecture. Highly dispersed hollow mesoporous silica spheres with huge hollow interiors and penetrating pores In the shelf were synthesized, which showed high surface area (670m2/g) and with a diameter of around 100mm. These mesoporous silica spheres are promising platforms for drug delivery because their huge cavities guarantee a large drug loading and the open meso pores make it possible to transport guest drugs. The pore size of hollow mesoporous silica spheres were tailored for adjusting the intracellular release of drug. This strategy could be extended as a genera) approach lo fabricate various hollow mesostructure by creating adequate stable lyotropic liquid crystal (LLC) system of composite micelle.

  11. Encapsulation of Anti-Tuberculosis Drugs within Mesoporous Silica and Intracellular Antibacterial Activities

    Directory of Open Access Journals (Sweden)

    Xin Xia

    2014-09-01

    Full Text Available Tuberculosis is a major problem in public health. While new effective treatments to combat the disease are currently under development, they tend suffer from poor solubility often resulting in low and/or inconsistent oral bioavailability. Mesoporous materials are here investigated in an in vitro intracellular assay, for the effective delivery of compound PA-824; a poorly soluble bactericidal agent being developed against Tuberculosis (TB. Mesoporous materials enhance the solubility of PA-824; however, this is not translated into a higher antibacterial activity in TB-infected macrophages after 5 days of incubation, where similar values are obtained. The lack of improved activity may be due to insufficient release of the drug from the mesopores in the context of the cellular environment. However, these results show promising data for the use of mesoporous particles in the context of oral delivery with expected improvements in bioavailability.

  12. TEMPLATED SYNTHESIS OF MESOPOROUS TITANIUM PHOSPHATES FOR THE SEQUESTRATION OF RADIONUCLIDES

    International Nuclear Information System (INIS)

    Several mesoporous titanium phosphate phases, with varying pore sizes, were prepared using non-ionic surfactants and easily handled titanium precursors under mild reaction conditions. Preliminary testing reveals that these materials have high affinity for certain radionuclides of environmental concern

  13. Effect of porosity on the Seebeck coefficient of mesoporous TiO2 thin films

    International Nuclear Information System (INIS)

    Mesoporous TiO2 films were prepared by using titanium tetraisopropoxide as the titania precursor and triblock copolymer as the structure directing agent. The synthesized mesoporous TiO2 film was confirmed to have the ordered pore structure with rutile phase by small angle and wide angle X-ray diffraction analyses. The mesoporous TiO2 film has the porosity range from 21.6 to 35.6%, and its Seebeck coefficient was changed according to its porosity, up to -88.6 ?V/K. From the obtained Seebeck coefficient, the ordered mesoporous TiO2 film was found to be a good candidate of thermal sensing layer of thin film thermal sensor.

  14. Mesoporous Silicon-Based Anodes for High Capacity, High Performance Li-ion Batteries Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A new high capacity anode composite based on mesoporous silicon is proposed. By virtue of a structure that resembles a pseudo one-dimensional phase, the active...

  15. Synthesis of mesoporous hollow carbon hemispheres as highly efficient Pd electrocatalyst support for ethanol oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Zaoxue; Meng, Hui; Li, Zihui; Shen, Pei Kang [The Key Laboratory of Low-carbon Chemistry and Energy Conservation of Guangdong Province, The State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-Sen University, Guangzhou, 510275 (China); Shi, Lei [Changling Catalyst Division, Sinopec Group, Yueyang 414012 (China)

    2010-05-15

    The synthesis procedure of the highly mesoporous hollow carbon hemispheres (HCHs) using glucose as carbon source and solid core mesoporous shell silica (SCMSS) as template and the formation mechanism of the HCHs have been presented. The HCHs show an ultrahigh surface area of 1095.59 m{sup 2} g{sup -1} and an average mesopore size of 9.38 nm. The hemispherical structure with large mesopores also results in the improvement in the mass transfer and therefore more concentrated ethanol solution can be used to increase the energy density. The additional advantage of the HCHs compared to the hollow carbon spheres is that they can provide the similar surface area at reduced volume. The current densities of ethanol oxidation on Pd nanoparticles supported on HCH (Pd/HCH) electrocatalyst are three times as many as on Pd/C at the same Pd loadings. (author)

  16. STUDY ON THE SYNTHESIS OF MESOPOROUS CERIA IN THE PRESENCE OF GLUCOSE AND ACRYLAMIDE

    Scientific Electronic Library Online (English)

    YUAN, LI; LAITAO, LUO.

    2009-06-01

    Full Text Available Mesoporous ceria with high specific surface area have been prepared using eerie ammonium nitrate and non-surfactants organic compounds glucose, acrylamide via hydrothermal method. The influence of the main synthesis variables have been studied, including cerium ion valence, composition of raw materi [...] als, hydrothermal temperature and time. XRD, TEM, TG and nitrogen adsorption techniques have been used to characterize the samples. Results indicate that cerium ion valence has the most important effect on surface area of mesoporous ceria. Cerium ion valence changing from +3 to +4 causes higher surface area of samples. Moreover the coexistence of glucose and acrylamide in the synthesis is essential to obtain samples with high surface areas, whereas surface areas of samples are lower in the absence of glucose or acrylamide. TEM shows that the mesoporous ceria are composed of three-dimensional disordered primary nanoparticles. The average size of primary particles and mesopores are both a few nanometers.

  17. STUDY ON THE SYNTHESIS OF MESOPOROUS CERIA IN THE PRESENCE OF GLUCOSE AND ACRYLAMIDE

    Directory of Open Access Journals (Sweden)

    YUAN LI

    2009-06-01

    Full Text Available Mesoporous ceria with high specific surface area have been prepared using eerie ammonium nitrate and non-surfactants organic compounds glucose, acrylamide via hydrothermal method. The influence of the main synthesis variables have been studied, including cerium ion valence, composition of raw materials, hydrothermal temperature and time. XRD, TEM, TG and nitrogen adsorption techniques have been used to characterize the samples. Results indicate that cerium ion valence has the most important effect on surface area of mesoporous ceria. Cerium ion valence changing from +3 to +4 causes higher surface area of samples. Moreover the coexistence of glucose and acrylamide in the synthesis is essential to obtain samples with high surface areas, whereas surface areas of samples are lower in the absence of glucose or acrylamide. TEM shows that the mesoporous ceria are composed of three-dimensional disordered primary nanoparticles. The average size of primary particles and mesopores are both a few nanometers.

  18. Large-scale template-free synthesis of ordered mesoporous platinum nanocubes and their electrocatalytic properties.

    Science.gov (United States)

    Cao, Yanqin; Yang, Yong; Shan, Yufeng; Fu, Chaoli; Viet Long, Nguyen; Huang, Zhengren; Guo, Xiangxin; Nogami, Masayuki

    2015-12-14

    Here we report a facile, one-pot and template-free approach to synthesize mesoporous monocrystalline Pt nanocubes with uniform shapes and sizes, in which small Pt particles with a size of ?5 nm are three-dimensionally and periodically built up into cubes with a size of ?50 nm. The forming process is illustrated through a novel meso-crystal self-assembly mechanism. Very interestingly, the mesoporous structures are ordered, which are thought to be beneficial to increase their catalytic activity. Compared with nonporous Pt nanoparticles and porous Pt nanoparticles without order, the ordered mesoporous Pt nanocubes exhibit a highly improved electrocatalytic ability for methanol and formic acid oxidation, and are potentially applicable as electrocatalysts for direct methanol and formic acid fuel cells. Furthermore, this approach can be used to synthesize other Pt-series metallic mesoporous nanoparticles, such as Pd. PMID:26399438

  19. A tri-continuous mesoporous material with a silica pore wall following a hexagonal minimal surface

    KAUST Repository

    Han, Yu

    2009-04-06

    Ordered porous materials with unique pore structures and pore sizes in the mesoporous range (2-50nm) have many applications in catalysis, separation and drug delivery. Extensive research has resulted in mesoporous materials with one-dimensional, cage-like and bi-continuous pore structures. Three families of bi-continuous mesoporous materials have been made, with two interwoven but unconnected channels, corresponding to the liquid crystal phases used as templates. Here we report a three-dimensional hexagonal mesoporous silica, IBN-9, with a tri-continuous pore structure that is synthesized using a specially designed cationic surfactant template. IBN-9 consists of three identical continuous interpenetrating channels, which are separated by a silica wall that follows a hexagonal minimal surface. Such a tri-continuous mesostructure was predicted mathematically, but until now has not been observed in real materials. © 2009 Macmillan Publishers Limited. All rights reserved.

  20. Metal free nitrogen doped hollow mesoporous graphene-analogous spheres as effective electrocatalyst for oxygen reduction reaction

    Science.gov (United States)

    Yan, Jing; Meng, Hui; Xie, Fangyan; Yuan, Xiaoli; Yu, Wendan; Lin, Worong; Ouyang, Wenpeng; Yuan, Dingsheng

    2014-01-01

    Nitrogen-doped hollow mesoporous carbon spheres has been synthesized from mesoporous silica spheres using glycine as carbon and nitrogen precursor. The wall of the spheres is composed by broken graphene. The metal free nitrogen-doped hollow mesoporous carbon spheres are proven to be active electrocatalyst for the oxygen reduction reaction in alkaline solution. A unique advantage of the nitrogen-doped hollow mesoporous carbon sphere is its methanol-tolerant property because of the absence of active metal. The catalytic activity is ascribed to the pyridinic-nitrogen formed during pyrolysis and the graphene-like structure. To the best of our knowledge this is the first report on the nitrogen-doped hollow mesoporous carbon sphere as a metal-free electrocatalyst for the oxygen reduction reaction which is an important reaction in fuel cell. The prepared mesoporous carbon material can also be used as catalyst support and find application both in the anode and cathode of fuel cell.