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71.
Subhendu Naskar Priyankar Paira Rupankar Paira Shyamal Mondal Arindam Maity Abhijit Hazra Krishnendu B. Sahu Pritam Saha Sukdeb Banerjee Peter Luger Manuela Webe Nirup B. Mondal 《Tetrahedron》2010,66(27-28):5196-5203
An environmentally benign protocol has been described for the synthesis of novel 2-(1′,3′-dihydro-1H-[2,3′]biindolyl-2′-ylidene)-indan-1,3-diones/bis-indolylindane-1,3-diones from ninhydrin and 3-substituted/unsubstituted indoles. It uses montmorillonite K-10 as catalyst in a solvent-free condition under microwave irradiation. The method was also used for the synthesis of novel bisindolylindeno[1,2-b]quinoxaline derivatives. 相似文献
72.
Manuela L.Q.A. Kaneko 《European Polymer Journal》2010,46(5):881-444
Rubber composites were obtained from natural (MT) or organomodified (O-MT) montmorillonite clay masterbatches and high molar mass poly(dimethylsiloxane)-gum (PDMS). The masterbatches were prepared by compounding MT or O-MT with a siloxane-polyether surfactant. The rubber composites were characterized by X-ray diffraction, small angle/wide angle X-ray scattering, scanning and transmission electron microscopies and tensile tests. The results showed that masterbatch compounding with O-MT improved the dispersion of this clay into the PDMS matrix. The morphology of the resulting composite showed a combination of intercalated and partially exfoliated clay layers with occasional clay aggregates. The addition of only 5 phr of O-MT into the PDMS matrix, via masterbatch compounding, improved the tensile strength as much as that obtained with the composite filled with 30 phr of O-MT clay prepared by the direct addition of the clay to PDMS. Moreover, the elongation at break was improved by at least 126%. 相似文献
73.
Bright red crystals of [Mn(H2O)6][BiI4]2 · 2H2O are obtained from a solution of MnI2, BiI3, and I2 in absolute ethanol, which is exposed to humid air. Reversible dehydratization sets in at about 50 °C. Added water decomposes the hydrate by irreversible precipitation of BiOI. The optical bandgap is about 1.9(1) eV. X‐ray diffraction on a single‐crystal revealed a monoclinic lattice (space group P21/c) with a = 760.39(4) pm, b = 1315.6(1) pm, c = 1398.37(7) pm, and β = 97.438(4)°. In the crystal structure zigzag chains of edge‐sharing [BiI2/1I4/2]– octahedra and linear strings of H2O‐bridged [Mn(H2O)6]2+ octahedra run parallel [100]. 相似文献
74.
75.
Quantum dots (QDs) are inorganic semiconductor nanocrystals that have unique optoelectronic properties responsible for bringing
together multidisciplinary research to impel their potential bioanalytical applications. In recent years, the many remarkable
optical properties of QDs have been combined with the ability to make them increasingly biocompatible and specific to the
target. With this great development, QDs hold particular promise as the next generation of fluorescent probes. This review
describes the developments in functionalizing QDs making use of different bioconjugation and capping approaches. The progress
offered by QDs is evidenced by examples on QD-based biosensing, biolabeling, and delivery of therapeutic agents. In the near
future, QD technology still faces some challenges towards the envisioned broad bioanalytical purposes.
相似文献
76.
Ester Sagristà Estelle Larsson Maryam Ezoddin Manuela Hidalgo Victòria Salvadó Jan Åke Jönsson 《Journal of chromatography. A》2010,1217(40):6153-6158
In this study, a three-phase hollow fiber liquid-phase microextraction (HF-LPME) method combined with liquid chromatography–mass spectrometry was developed for direct determination of four non-steroidal anti-inflammatory drugs (ketoprofen, naproxen, diclofenac and ibuprofen) in sewage sludge. The drugs were extracted from non-spiked and spiked slurry samples with different amounts of sludge into an organic phase and then back-extracted into an aqueous phase held in the lumen of the hollow fiber. High enrichment factors ranging from 2761 to 3254 in pure water were achieved. In sludge samples, repeatability and inter-day precision were tested with relative standard deviation values between 10–18% and 7–15%, respectively. Average concentrations of 29 ± 9, 138 ± 2, 39 ± 5 and 122 ± 7 ng/g were determined in dried sludge from Källby sewage treatment plant (Sweden) for ketoprofen, naproxen, diclofenac and ibuprofen, respectively. 相似文献
77.
Wolfgang G. Kreyling Pratim Biswas Maria E. Messing Neil Gibson Marianne Geiser Alexander Wenk Manoranjan Sahu Knut Deppert Izabela Cydzik Christoph Wigge Otmar Schmid Manuela Semmler-Behnke 《Journal of nanoparticle research》2011,13(2):511-524
The intensive use of nano-sized titanium dioxide (TiO2) particles in many different applications necessitates studies on their risk assessment as there are still open questions on their safe handling and utilization. For reliable risk assessment, the interaction of TiO2 nanoparticles (NP) with biological systems ideally needs to be investigated using physico-chemically uniform and well-characterized NP. In this article, we describe the reproducible production of TiO2 NP aerosols using spark ignition technology. Because currently no data are available on inhaled NP in the 10?C50 nm diameter range, the emphasis was to generate NP as small as 20 nm for inhalation studies in rodents. For anticipated in vivo dosimetry analyses, TiO2 NP were radiolabeled with 48V by proton irradiation of the titanium electrodes of the spark generator. The dissolution rate of the 48V label was about 1% within the first day. The highly concentrated, polydisperse TiO2 NP aerosol (3?C6 × 106 cm?3) proved to be constant over several hours in terms of its count median mobility diameter, its geometric standard deviation, and number concentration. Extensive characterization of NP chemical composition, physical structure, morphology, and specific surface area was performed. The originally generated amorphous TiO2 NP were converted into crystalline anatase TiO2 NP by thermal annealing at 950 °C. Both crystalline and amorphous 20-nm TiO2 NP were chain agglomerated/aggregated, consisting of primary particles in the range of 5 nm. Disintegration of the deposited TiO2 NP in lung tissue was not detectable within 24 h. 相似文献
78.
Given an integral commutative residuated lattice L, the product L × L can be endowed with the structure of a commutative residuated lattice with involution that we call a twist-product. In the present paper, we study the subvariety ${\mathbb{K}}$ of commutative residuated lattices that can be represented by twist-products. We give an equational characterization of ${\mathbb{K}}$ , a categorical interpretation of the relation among the algebraic categories of commutative integral residuated lattices and the elements in ${\mathbb{K}}$ , and we analyze the subvariety of representable algebras in ${\mathbb{K}}$ . Finally, we consider some specific class of bounded integral commutative residuated lattices ${\mathbb{G}}$ , and for each fixed element ${{\bf L} \in \mathbb{G}}$ , we characterize the subalgebras of the twist-product whose negative cone is L in terms of some lattice filters of L, generalizing a result by Odintsov for generalized Heyting algebras. 相似文献
79.
Coupled cell systems are networks of dynamical systems (the cells), where the links between the cells are described through the network structure, the coupled cell network. Synchrony subspaces are spaces defined in terms of equalities of certain cell coordinates that are flow-invariant for all coupled cell systems associated with a given network structure. The intersection of synchrony subspaces of a network is also a synchrony subspace of the network. It follows, then, that, given a coupled cell network, its set of synchrony subspaces, taking the inclusion partial order relation, forms a lattice. In this paper we show how to obtain the lattice of synchrony subspaces for a general network and present an algorithm that generates that lattice. We prove that this problem is reduced to obtain the lattice of synchrony subspaces for regular networks. For a regular network we obtain the lattice of synchrony subspaces based on the eigenvalue structure of the network adjacency matrix. 相似文献
80.