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951.
952.
How Different Characterization Techniques Elucidate the Nature of the Gold Species in a Polycrystalline Au/TiO2 Catalyst
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Prof. Wolfgang Grünert Dr. Dennis Großmann Dr. Heshmat Noei Dr. Marga‐Martina Pohl Dr. Ilya Sinev Dr. Andrea De Toni Dr. Yuemin Wang Prof. Martin Muhler 《化学,工程师,技术》2014,86(11):1883-1889
TiO2‐supported gold species were prepared via the deposition‐precipitation route, with conservation of the initial speciation by freeze‐drying. The structural and electronic properties of the Au species were investigated by X‐ray absorption spectroscopy, electron microscopy, and IR spectroscopy of adsorbed CO in four states. Exclusively AuIII was deposited on the TiO2 surface in patches ranging from isolated Au ions to three‐dimensional clusters. This paper illustrates in detail the unique contributions of all characterization techniques to this structural model. 相似文献
953.
Production and isolation of chitosan from Aspergillus terreus and application in tin(II) adsorption
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Li‐Chun Cheng Tzung‐Shian Wu Jian‐Wen Wang Szu‐Han Wu Mei‐Hui Chung Yi‐Ming Kuo Cheng‐Hsien Tsai 《应用聚合物科学杂志》2014,131(12)
Fed‐batch fermentation was used for biomass and fungal chitosan production by Aspergillus terreus (BCRC 32068) grown in a potato dextrose agar medium. The polysaccharides were extracted by an alkali–acid treatment, and structural investigations by X‐ray diffraction, Fourier transform infrared analysis, and viscosity and thermal analysis were done. A high level of chitosan was extracted from A. terreus; this implied that it was feasible to produce chitosan from industrial waste mycelia. Fungal chitosan derived from A. terreus showed the highest adsorption capacity for Sn(II). The order of Sn(II) adsorption capacity for these chitosanaceous materials was Fungal chitosan > Chitin > Biomass. Fungal chitosan derived from A. terreus was well correlated with Langmuir's isotherm model. The maximum capacity for Sn(II) sorption deduced from the use of the Langmuir isotherm equation was 303 mg/g; this was significantly higher than that of A. terreus. Fungal chitosan is an easy and cost‐effective material for the abatement of pollution. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40436. 相似文献
954.
In this investigation, the porous structure of polyaniline/MgO (PANI/MgO) composites has been successfully synthesized by in‐situ oxidative polymerization method. The as‐prepared materials were characterized by Ultraviolet–visible absorption spectroscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy. The obtained composites, for the first time, are used as an adsorbent for the removal of the sulfonated anionic dye reactive orange 16 (RO) from aqueous solution. The equilibrium adsorption isotherms of RO on the PANI/MgO composites were analyzed by Langmuir and Freundlich models, suggesting that the Langmuir model provides the better correlation of the experimental data and maximum adsorption capacity was found to be 558.4 mg g?1. In addition, adsorption kinetics was followed by both pseudo‐first‐order and pseudo‐second‐order, but the latter model matches the results much better than the former one. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40210. 相似文献
955.
Magnetic polymeric nanoparticles functionalized by mannose‐rhodamine conjugate for detection of E. coli
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Mannose‐rhodamine (Rh) conjugate (80% yield) was synthesized in a one‐pot reaction and immobilized onto magnetic polymeric nanoparticles (MPNP; 43% magnetic content) of poly(styrene/divinyl benzene/acrylic acid). The resulting nanoparticles contained MPNP as a substrate, mannose as an E. coli receptor and Rh as a fluorescent signaling unit. TEM imaging clearly demonstrated that multiple mannose‐Rh MPNPs could be captured by E. coli strain ORN178. The fluorescent signal from captured nanoparticles was emitted at 580 nm. These results indicate that mannose‐Rh MPNP offers a simple and rapid strategy for bacterial detection. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40012. 相似文献
956.
Feldspar/titanium dioxide/chitosan as a biophotocatalyst hybrid for the removal of organic dyes from aquatic phases
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Feldspar/titanium dioxide/chitosan hybrid, a photoactive biocompatible adsorbent for anionic dyes, was synthesized, characterized, and successfully tested. The adsorbent characterization, pH role, adsorbent dose effect, equilibrium data, kinetic plats, and thermodynamic parameters are reported. The point of zero charge for the hybrid was measured to be 8.3, and the most favorable pH range for the adsorption process was found to be below this pH value. The adsorption equilibrium study demonstrated that the Freundlich model was best fitted to the experimental data. Without UV light exposure, the prepared adsorbent adsorbed 72 mg of Acid Black 1 (AB1)/g of sorbent (86% removal) from a 100‐mL solution with an initial dye concentration of 50 mg/L, whereas UV irradiation resulted in an increase in the elimination of AB1 dye (97% removal). The kinetic data was depicted well by the pseudo‐second‐order model. The thermodynamic parameters indicated that the reaction between the hybrid and the dye was exothermic and also spontaneous at lower temperatures. In the batch desorption process, several aqueous solutions adjusted to different pH values were tested, and the best desorption performance (90% desorption) was achieved at pH 11. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40247. 相似文献
957.
CO2 Adsorption capacity of activated N‐doping porous carbons prepared from graphite nanofibers/polypyrrole
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In this study, N‐doping porous carbons (NPCs) with a 3D aperiodic hierarchical and layered structure were prepared by the sodium hydride (NaOH) activation of graphite nanofibers (GNFs)/polypyrrole (PPY) composites. The effects of the N groups and structural features on the CO2 adsorption capacity of NPCs were investigated by N2 full isotherms, XRD, SEM, and TEM. The CO2 adsorption capacity was measured by the CO2 isothermal adsorption at 25°C and 1 atm. It was found that GNFs served as a substrate and layered graphitic carbons were formed by the thermal annealing of PPY. The content of N groups and textural properties of NPCs were enhanced with increasing activation temperature, resulting in improved CO2 adsorption capacity. The CO2 adsorption isotherms showed that GPK‐600 exhibited the best CO2 adsorption capacity of 88.8 mg/g when the activation temperature was 600°C. The result indicates that the pore size and its distribution of NPCs lead to feasible contact CO2, and the presence of high N groups on the NPCs could have resulted in further stabilization of the surface effect. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40517. 相似文献
958.
TEOS as an improved alternative for chitosan beads cross‐linking: A comparative adsorption study
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Guillermo J. Copello María E. Villanueva Joaquín A. González Sofía López Egües Luis E. Diaz 《应用聚合物科学杂志》2014,131(21)
In this work the use of tetraethoxysilane (TEOS) for cross‐linking of chitosan hydrogel beads was studied at the level of 1 mmol TEOS per gram of chitosan. They were compared with glutaraldehyde and epichlorohydrin cross‐linked beads. The hydrogels were characterized by FTIR, SEM, water content, nitrogen content, and their point of zero charge. The performance of the anionic dye Remazol Black (RB) and the cationic Cd(II) adsorptions was assessed in order to characterize the sorbate–sorbent interaction. Adsorption experimental data were analyzed using two‐ and three‐parameter isotherm models along with the evaluation of mean adsorption energy and standard free energy. The adsorption was observed to be pH dependent. The uptake rate of RB and Cd(II) showed that the three type of beads followed a similar kinetic behavior. For both sorbates the TEOS cross‐linked beads showed the higher maximum adsorption capacity, followed by epichlorohydrin and glutaraldehyde cross‐linked beads. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41005. 相似文献
959.
Synthesis of a novolac‐based 3‐aminopropylsiloxane resin and its application for the removal of Cu2+, Cr3+, and Ni2+ from electroplating wastewater
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Khaled Abou‐El‐Sherbini Mohamed A. Nour Abd‐El‐Ghany Soliman Saad S. Elmorsy 《应用聚合物科学杂志》2014,131(21)
Novolac resin was modified with 3‐aminopropyltrimthoxysilane to obtain phenol‐formaldehyde‐aminopropylsiloxane resin (PF‐APS). Fourier transformation infra‐red spectra, thermogravimetric analysis, elemental analysis, and pH‐metric titration were used to characterize PF‐APS. Its chemical formula was suggested to be C14H12.49N0.1O2Si0.1. The resin shows high experimental metal ions uptake capacity within short time of equilibration. The metal capacity was determined by atomic absorption spectrometry to be 0.787 mEq Cu/g. Maximum separation efficiencies of Cu2+, Cr3+, and Ni2+ from aqueous solutions on PF‐APS were at pH 8.0 and time of stirring 60 min; 94.0%, 90.8%, 83.2%, respectively. No significant interference from the background ions Na+, Cl?, and was observed on the separation process. The heavy metal ions were eluted using 0.01 mol L?1 EDTA at 65°C releasing >94% of the separated metal ions. The method of separation was applied successfully to remove the heavy metal ions Cu2+, Cr3+, and Ni2+ from electroplating wastewater from Dekirnis, Dakahlia Governorate, Egypt. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40993. 相似文献
960.