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71.
Seiji Akiyama Mamiko Nakabayashi Naoya Shibata Tsutomu Minegishi Yusuke Asakura Md. Abdulla‐Al‐Mamun Takashi Hisatomi Hiroshi Nishiyama Masao Katayama Taro Yamada Kazunari Domen 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(39):5468-5476
An improved variation of highly active/durable O2‐evolving LaTiO2N powder‐based photoelectrode has been fabricated by pre‐cleaning the powder with mild polysulfonic acid and by homogeneous deposition of CoOx co‐catalyst aided by microwave annealing. The treatment in aqueous solution of poly(4‐styrene sulfonic acid) results in removal of surface LaTiO2N layers, forming fine pores in the crystallites. The CoOx co‐catalyst by microwave deposition in Co(NH3)6Cl3/ethylene glycol homogeneously covers the particle surface. The LaTiO2N powder is fabricated into particle‐transferred electrodes on Ti thin film supported on solid substrate. The modified LaTiO2N grains on the electrode serve as a highly active O2‐evolving photoanode achieving 8.9 mA cm?2 of the photocurrent density at 1.23 V versus reversible hydrogen electrode (RHE) in 0.1 m NaOH (pH 13) under solar‐simulator irradiation Airmass 1.5 Global (AM 1.5G). The activity has been much improved, compared with conventional LaTiO2N treated in mineral acid or with CoOx deposited by impregnation. The new electrode also exhibits better durability in fixed‐potential chronoamperometric tests under AM 1.5G irradiation. 相似文献
72.
There is some doubt as to the effectiveness of opioids in the management of neuropathic pain. We therefore examined the actions of morphine and the opioid-like peptide nociceptin (both 1 mu) on dorsal root ganglion (DRG) neurons that were isolated from control or from nerve-injured rats. Both substances reduced omega-conotoxin (CTX) GVIA-sensitive, N-type Ca2+ channel current and small persistent nifedipine/ CTX-insensitive (non-N, non-L type) current. Nifedipine-sensitive L-type current was unaffected. The effect of nociceptin was antagonized by naloxone benzoylhydrazone (nalbzoh) but not by naloxone. Sciatic nerve section (axotomy) profoundly reduced the effects of morphine and the mu-receptor agonist D-ala2, N-Me-Phe4,Gly-ol5 enkephalin (DAMGO). The effect of the kappa-agonist [(+)-(5alpha,7alpha, 8beta)-N-methyl-N-(7-(1-pyrrolidinyl)-1-oxaspiro(4, 5)dec-8-yl)-benzeneacetamide] (U69593) was unchanged, whereas the effect of nociceptin was increased. All agonists produced their strongest effects on the small, putative nociceptive cells and their weakest effects on the largest cells. The delta-receptor agonist, enkephalin D-pen2,5 (DPDPE), was without effect on control or on axotomized cells. These and other data suggest that the functional downregulation of mu-opioid receptors on sensory nerves contributes to the poor efficacy of opioids in neuropathic pain. Also, the increased effectiveness of nociceptin after axotomy supports the hypothesis that its actions are mediated via a "non-opioid" receptor. Pronounced suppression of Ca2+ channel current in axotomized DRG neurons by nociceptin led to a reduction in Ca2+-dependent K+ conductance and a marked increase in excitability. Despite this, the spinal administration of nociceptin or agonists that activate ORL1 (opioid-like orphan receptor) may prove to be of clinical interest in the management of neuropathic pain. 相似文献
73.
In this paper, a novel ambient intelligence (AmI) platform is proposed to facilitate fast integration of different control algorithms, device networks and user interfaces. This platform defines the overall hardware/software architecture and communication standards. It consists of four layers, namely the ubiquitous environment, middleware, multi-agent system and application layer. The multi-agent system is implemented using Java Agent DEvelopment (JADE) framework and allows users to incorporate multiple control algorithms as agents for managing different tasks. The Universal Plug and Play (UPnP) device discovery protocol is used as a middleware, which isolates the multi-agent system and physical ubiquitous environment while providing a standard communication channel between the two. An XML content language has been designed to provide standard communication between various user interfaces and the multi-agent system. A mobile ubiquitous setup box is designed to allow fast construction of ubiquitous environments in any physical space. The real time performance analysis shows the potential of the proposed AmI platform to be used in real-life AmI applications. A case study has also been carried out to demonstrate the possibility of integrating multiple control algorithms in the multi-agent system and achieving a significant improvement on the overall offline learning performance. 相似文献
74.
Shahanavaj Khan Anees A. Ansari Christian Rolfo Andreia Coelho Maha Abdulla Khayal Al-Khayal 《Science and Technology of Advanced Materials》2013,14(1):364-373
AbstractCerium oxide nanocrystals (CeO2-NCs) exhibit superoxide dismutase and catalase mimetic activities. Based on these catalytic activities, CeO2-NCs have been suggested to have the potential to treat various diseases. The crystalline size of these materials is an important factor that influences the performance of CeO2-NCs. Previous reports have shown that several metal-based nanocrystals, including CeO2-NCs, can induce cytotoxicity in cancer cells. However, the underlying mechanisms have remained unclear. To characterize the anticancer activities of CeO2-NCs, several assays related to the mechanism of cytotoxicity and induction of apoptosis has been performed. Here, we have carried out a systematic study to characterize CeO2-NCs phase purity (X-ray diffraction), morphology (electron microscopy), and optical features (optical absorption, Raman scattering, and photoluminescence) to better establish their potential as anticancer drugs. Our study revealed anticancer effects of CeO2-NCs in HT29 and SW620 colorectal cancer cell lines with half-maximal inhibitory concentration (IC50) values of 2.26 and 121.18 μg ml–1, respectively. Reductions in cell viability indicated the cytotoxic potential of CeO2-NCs in HT29 cells based on inverted and florescence microscopy assessments. The mechanism of cytotoxicity confirmed by estimating possible changes in the expression levels of Bcl2, BclxL, Bax, PARP, cytochrome c, and β-actin (control) proteins in HT29 cells. Down-regulation of Bcl2 and BclxL and up-regulation of Bax, PARP, and cytochrome c proteins suggested the significant involvement of CeO2-NCs exposure in the induction of apoptosis. Furthermore, biocompatibility assay showed minimum effect of CeO2-NCs on human red blood cells. 相似文献
75.
Polyazomethinethiosemicarbazone (PATS) metal complexes of Ni(II), Co(II), Cu(II), Zn(II), Cd(II) and Hg(II) metal ions were prepared by reacting the polymer ligand (PATS) with the appropriate metal salt in refluxing DMSO. Elemental analyzes as well as FTIR and electronic spectral data are presented to confirm the formulation of the isolated materials. The spectral data show that the ligand polymer is bonded to the metal ions via the thiol sulfur atom and coordinated through the nitrogen of azomethine group. The DC electrical conductivity measurements of PATS and its metal complexes were measured in the range 300–500 K in the annealed and 5% iodine doped forms. The products gave electrical conductivity in the semiconducting region that increased by heat. The DC electrical conductivity is interpreted using the band gap theory using solitons, polarons and bipolarons. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
76.
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78.
A model that determines nodal demands by making tracer concentration measurements at specific nodes is developed. The model minimizes the difference between calculated and measured tracer concentrations to determine the unknown demands. Even-, over-, and under-determined cases are considered. For the purpose of verifying the model, tracer concentrations obtained by the model for known demands are considered as measurements. Results showed that the model made very accurate prediction of the unknown demands for both the even-, and the over-determined cases. The under-determined case made less accurate but still good estimates of the unknown demands for the scenarios considered here. The relationship between the sensitivity of the measurement location to the unknown demand and the accuracy of the determined demand is verified. Results showed that the model makes accurate estimation of the unknown demands if measurements are made at sensitive nodes while errors are introduced to the determined demand as a result of assuming measurements at nodes of low sensitivity. 相似文献
79.
80.
The occurrence of aflatoxin in commodities imported into Qatar was investigated from 1999 to 2000. During the 4 years, 351 samples of susceptible commodities were analysed. Aflatoxin was detected in 71 (20%) samples in the range 0.1-20 microg kg(-1) and in 50 (14%) samples above the permitted level of 20 microg kg(-1). The highest incidence and levels of aflatoxin contamination were recorded in pistachio without shell followed by pistachio with shell. Aflatoxin levels >20 microg kg(-1) in the pistachio samples varied from 8.7 to 33%. The highest level of total aflatoxin found in pistachio without shell was 289 microg kg(-1). A few samples of corn and corn products (three of 54 analysed), peanut and peanut products (nine of 42 analysed) and other nuts like almond, walnut and cashew (one of 40 analysed) were found contaminated with low levels (0.1-20 microg kg(-1)) of aflatoxins. Only one sample of custard powder and one sample of roasted peanut were found with aflatoxin >20 microg kg(-1) 相似文献