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991.
Alkaline–Acid Zn–H2O Fuel Cell for the Simultaneous Generation of Hydrogen and Electricity 下载免费PDF全文
Pingwei Cai Yan Li Genxiang Wang Prof. Dr. Zhenhai Wen 《Angewandte Chemie (International ed. in English)》2018,57(15):3910-3915
An alkaline–acid Zn–H2O fuel cell is proposed for the simultaneous generation of electricity with an open circuit voltage of about 1.25 V and production of H2 with almost 100 % Faradic efficiency. We demonstrate that, as a result of harvesting energy from both electrochemical neutralization and electrochemical Zn oxidation, the as‐developed hybrid cell can deliver a power density of up to 80 mW cm?2 and an energy density of 934 Wh kg?1 and maintain long‐term stability for H2 production with an output voltage of 1.16 V at a current density of 10 mA cm?2. 相似文献
992.
993.
Verónica Fernández‐Luna Dr. Pedro B. Coto Dr. Rubén D. Costa 《Angewandte Chemie (International ed. in English)》2018,57(29):8826-8836
Over the last decades, fluorescent proteins (FPs) have been extensively employed for imaging and tracing in cell biology and medicine. However, their application for lighting devices like light‐emitting diodes (LEDs) and lasers has recently started. The interest of FPs is the result of their good photoluminescence features (high emission efficiency with a narrow spectrum and a high photon‐flux saturation), good photostability, sustainable production by bacteria, and eco‐friendly recycling. Their low stability at high temperatures as well as the need for an aqueous environment have, however, strongly limited their use in optoelectronics. This has recently been circumvented with new coating systems that are paving the way for the entrance of FPs into the LED field. In this Minireview, we summarize the first steps taken by a few groups towards the development of bio‐hybrid white LEDs (Bio‐HWLEDs) with a focus on using FPs as color down‐converters, highlighting the state of the art and challenges associated with this emerging field. 相似文献
994.
Karim Dahmouche Mohamed Atik Nilson C. Mello Tito J. Bonagamba Horacio Panepucci Michel A. Aegerter Patrick Judeinstein 《Journal of Sol-Gel Science and Technology》1997,8(1-3):711-715
Two families of hybrid organic-inorganic composites exhibiting Li+ ionic conduction (ORMOLYTES) have been prepared by the sol-gel process. The first family, prepared from a mixture of 3-isocyanatopropyltriethoxysilane, O,O Bis (2-aminopropyl)-polyethyleneglycol (or O,O Bis (2-aminopropyl)-polypropyleneglycol) and lithium salt, presents chemical bonds between the organic and the inorganic phase and an ionic conductivity higher than 10-4 S m-1 at room temperature. Their properties have been related to their structure using liquid state NMR measurements of 7Li between -100°C and +100°C and the DMTA technique. In the second family, prepared by ultrasonic method from a mixture of tetraethoxysilane (TEOS), polyethyleneglycol (PEG) and lithium salt, the organic and inorganic phases are not chemically bonded. Ionic conductivity has been studied as a function of the polymer chain length and concentration. Values of up to 10-2 S m-1 at room temperature have been obtained (with a silica-PEG300 system, PEG/TEOS = 40% in weight). Again, structure was investigated by liquid state 7Li NMR measurements. 相似文献
995.
An improved amperometric glucose biosensor based on glucose oxidase immobilized in sol–gel chitosan/silica hybrid composite film, which was prepared from chitosan (CS) and methyltrimethoxysilane (MTOS), on the surface of Prussian blue (PB)-modified glass carbon electrode was developed. The film was characterized by FT-IR. Effects of some experimental variables such as ratio of CS to silica, buffer pH, temperature, and applied potential on the current response of the biosensor were investigated. The biosensor fabricated under optimal conditions had a linear response to glucose over the range 5.0×10–5 to 2.6×10–2 M with a correlation coefficient of 0.9948 and a detection limit of 8.0×10–6 M based on S/N =3. The biosensor had a fast response time of less than 10 s, a high sensitivity of 420 nA mM–1, a long-term stability of over 60 days, and a good selectivity. The apparent Michaelis–Menten constant Km was found to be 3.2×10–3 M. The activation energy for enzymatic reaction was calculated to be 21.9 kJ mol–1. This method has been used to determine the glucose concentration in real human blood samples. 相似文献
996.
Maria Zaharescu Maria Crisan Luminita Predoana Mariuca Gartner Dana Cristea Stefania Degeratu Elena Manea 《Journal of Sol-Gel Science and Technology》2004,32(1-3):173-177
In the present work, the influence of substituted Si-alkoxides on the structural and optical properties of films obtained in the SiO2-TiO2 system was studied. Methyltriethoxysilane (MTEOS) and 3-(tri-methoxysilyl)propyl methacrylate (TSPM) were used as SiO2 sources and Ti(OBu)4 was used as TiO2 source. Acetylacetone was added to the Ti(OBu)4 as chelating agent and the synthesis was carried out in acid medium. The films were deposited on oxidized Si-wafers by spin-coating. The films were characterized by XRD, spectro-ellipsometry (SE), and atomic force microscopy (AFM). The results obtained have shown that in the case of hybrid films the desired thickness could be obtained in a single deposition step. The thickness of the films and the optical properties are controlled by the bulkiness of the organic substitute bounded to Si. Among other optical applications, the potential use of such films as optical waveguides is proposed. 相似文献
997.
Ayyappan Subbiah 《Journal of solid state chemistry》2005,178(4):1321-1325
A novel tin(II) phenylbis(phosphonate) compound has been synthesized hydrothermally and its structure has been determined by single crystal X-ray diffraction. The structure is monoclinic, space group P21/c (no. 14), a=4.8094(4), b=16.2871(13), ; β=106.292(6)°, , Z=2. The three-dimensional structure consists of 3-coordinated tin and 4-coordinated phosphorus double layers separated (pillared) by phenyl rings. These phenyl rings are placed 4.8 Å apart along the a-axis in the structure resulting in lower surface area (∼14 m2/g). The porosity has been increased by replacing phenyl groups by methyl groups (∼31 m2/g). 相似文献
998.
Photoluminescent multilayers were fabricated by layer-by-layer deposition between europium-substituted heteropolytungstate K13[Eu(SiW11O39)2]·28H2O (denoted ESW) and a cationic polymer of quaternized poly(4-vinylpyridine) partially complexed with osmium bis(2,2′-bipyridine) (denoted as QPVP-Os) on glassy carbon and quartz substrates. The resulting photoluminescent organic-inorganic hybrid multilayers were characterized by electrochemical impedance spectroscopy, UV-Vis absorption spectrometry, cyclic voltammetry and photoluminescence spectra. Electrochemical impedance spectroscopy, UV-Vis absorption spectrometry and cyclic voltammetry results demonstrated that the multilayers were regular growth each layer adsorption. The photoluminescent properties of the films at room temperature were investigated to show the characteristic Eu3+ emission pattern of 5D0→7Fj. 相似文献
999.
K. Gigant U. Posset G. Schottner L. Baia W. Kiefer J. Popp 《Journal of Sol-Gel Science and Technology》2003,26(1-3):369-373
Hydrolysis, polycondensation and UV-induced radical polymerization processes in binary and ternary mixtures of vinyltriethoxysilane (VTEOS), tetraethoxysilane (TEOS), and several polyfunctional acrylates as reactive diluents were studied by means of FT-Raman and confocal micro-Raman spectroscopy. The study comprises measurements on sols, gels, xerogels, and thin films applied on top of glass slides and polymeric substrates. Characteristic Raman bands are utilized to gain information about the structural evolution, inorganic network connectivity, and organic cross-linking reactions. Supplementary, 29Si-NMR spectroscopic data are considered and correlated with Raman data. Structure-property correlations based on spectroscopic and mechanical data are outlined and discussed. It is demonstrated that thin hybrid polymer films may be studied in-situ by means of confocal micro-Raman spectroscopy. 相似文献
1000.
本文对一些含Mo-Mo原子间多重键的分子或离子进行了研究,分析了它们的电子结构和化学键提出其原子杂化轨道的形式,揭示了过渡金属原子间多重键的结构特征。 相似文献