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351.
Chang Shih-Fu Anastassiou Dimitris Eleftheriadis Alexandros Pavlik John V. 《Multimedia Tools and Applications》1997,5(2):115-118
Multimedia Tools and Applications - 相似文献
352.
C Dendrinou-Samara G Tsotsou LV Ekateriniadou AH Kortsaris CP Raptopoulou A Terzis DA Kyriakidis DP Kessissoglou 《Canadian Metallurgical Quarterly》1998,71(3-4):171-179
Complexes of Zn(II), Cd(II) and Pt(II) metal ions with the anti-inflammatory drugs, 1-methyl-5-(p-toluoyl)-1H-pyrrole-2-acetic acid (Tolmetin), alpha-methyl-4-(2-methylpropyl)benzeneacetic acid (Ibuprofen), 6-methoxy-alpha-methylnaphthalene-2-acetic acid (Naproxen) and 1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indole-3-acetic acid (indomethacin) have been synthesized and characterized. In the structurally characterized Cd(naproxen)2 complex the anti-inflammatory drugs acts as bidentate chelate ligand coordinatively bound to metal ions through the deprotonated carboxylate group. Crystal data for 1: [C32H26O8Cd], orthorhombic, space group P22(1)2(1), a = 5.693(2) (A), b = 8.760(3) (A), c = 30.74(1) (A), V = 1533(1) A3, Z = 2. Antibacterial and growth inhibitory activity is higher than that of the parent ligands or the platinum(II) diamine compounds. 相似文献
353.
George Lampropoulos Nikos Passas Alexandros Kaloxylos Lazaros Merakos 《Wireless Personal Communications》2007,43(3):889-906
Current trends in cellular telecommunications suggest the incorporation of Wireless Local Area Networks (WLANs) as supplementary
access technologies into the existing cellular infrastructure. Overlay network architectures are expected to improve both
service provision and resource utilization under the condition that sophisticated architectural options are followed. Many
proposals suggest that all active connections be handled through the same access network technology. However, this is not
believed to be efficient in a heterogeneous environment. Therefore, a mechanism that allows each connection of a terminal
to be served by different radio access technology is introduced. Based on a tight coupling architecture for interworking between
Universal Mobile Telecommunications System (UMTS) and WLANs, the proposed scheme combines a sophisticated decision mechanism
with flexible connection management in a way that ensures seamless service continuity during handover. The performance of
the system is evaluated using a detailed simulation model and compared against existing architectures. Simulation results
indicate an improvement in parameters such as connection and handover blocking probabilities, which justifies the enhancement
in the overall usage of network resources when connections are handled separately. 相似文献
354.
The ever growing amount of data generated and consumed on the move using portable devices gives rise to serious data management issues. The fact that each person may own and is likely to carry several such devices further aggravates this problem. On the other hand, new opportunities for achieving cleverer device interaction emerge due to the increased wireless networking capabilities of wearable and portable devices. This paper introduces OmniStore, a system that combines portable devices and infrastructure-based services to relieve the user from explicit and time consuming file management tasks. Our approach is to let devices communicate with each other as well as with a repository service, in an opportunistic and asynchronous fashion, to perform a variety of file movement and copying actions behind the scenes, which would have typically required considerable explicit user interaction. 相似文献
355.
Williams J Wood J Pandarinathan L Karanian DA Bahr BA Vouros P Makriyannis A 《Analytical chemistry》2007,79(15):5582-5593
The endocannabinoid system's biological significance continues to grow as novel endocannabinoid metabolites are discovered. Accordingly, a myopic view of the system that focuses solely on one or two endocannabinoids, such as anandamide or 2-arachidonoyl glycerol, is insufficient to describe the biological responses to perturbations of the system. Rather, the endocannabinoid metabolome as a whole must be analyzed. The work described here is based on liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometry. This method has been validated to quantify, in a single chromatographic run, the levels of 15 known or suspected metabolites of the endocannabinoid system in the rat brain and is applicable to other biological matrixes. We have obtained an endocannabinoid profile specifically for the frontal cortex of the rat brain and have determined anandamide level differences following the administration of the fatty acid amide hydrolase inhibitor AM374. 相似文献
356.
Farah Javed Hafiz Muhammad Shahbaz Asad Nawaz Amin N. Olaimat Alexandros Ch. Stratakos Agung Wahyono Sadia Munir Ghulam Mueen-ud-din Zeshan Ali Jiyong Park 《Comprehensive Reviews in Food Science and Food Safety》2021,20(3):2699-2715
Furan is generally produced during thermal processing of various foods including baked, fried, and roasted food items such as cereal products, coffee, canned, and jarred prepared foods as well as in baby foods. Furan is a toxic and carcinogenic compound to humans and may be a vital hazard to infants and babies. Furan could be formed in foods through thermal degradation of carbohydrates, dissociation of amino acids, and oxidation of polyunsaturated fatty acids. The detection of furan in food products is difficult due to its high volatility and low molecular weight. Headspace solid-phase microextraction coupled with gas chromatography/mass spectrometer (GC/MS) is generally used for analysis of furan in food samples. The risk assessment of furan can be characterized using margin of exposure approach (MOE). Conventional strategies including cooking in open vessels, reheating of commercially processed foods with stirring, and physical removal using vacuum treatment have remained unsuccessful for the removal of furan due to the complex production mechanisms and possible precursors of furan. The innovative food-processing technologies such as high-pressure processing (HPP), high-pressure thermal sterilization (HPTS), and Ohmic heating have been adapted for the reduction of furan levels in baby foods. But in recent years, only HPP has gained interest due to successful reduction of furan because of its nonthermal mechanism. HPP-treated baby food products are commercially available from different food companies. This review summarizes the mechanism involved in the formation of furan in foods, its toxicity, and identification in infant foods and presents a solution for limiting its formation, occurrence, and retention using novel strategies. 相似文献
357.
358.
各种灵活的京都机制已经作为以市场为基础的解决气候变化的方法发展起来了。更具体的说,清洁发展机制(CDM)是指一个工业化国家通过在发展中国家实施减排项目(特别是可再生能源项目)来实现其部分减排义务的一种灵活机制。目前发展中国家没有承担减少温室气体排放方面的义务。介绍了京都议定书的清洁发展机制促进可再生能源(RES)投资的能力,并且分析了在CDM机制下小型项目的发展潜力。 相似文献
359.
Behavior of Escherichia coli O157:H7 during the manufacture and ripening of feta and telemes cheeses
Pasteurized whole ewe's and cow's milk was used in the manufacture of Feta end Telemes cheeses, respectively, according to standard procedures. In both cases, the milk had been inoculated with Escherichia coli O157:H7 at a concentration of ca. 5.1 log CFU/ml and with thermophilic or mesophilic starter cultures at a concentration of ca. 5.3 to 5.6 log CFU/ml. In the first 10 h of cheesemaking, the pathogen increased by 1.18 and 0.82 log CFU/g in Feta cheese and by 1.56 and 1.35 log CFU/ g in Telemes cheese for the trials with thermophilic and mesophilic starters, respectively. After 24 h of fermentation, a decrease in E. coli O157:H7 was observed for all trials. At that time, the pH was reduced to 4.81 to 5.10 for all trials. Fresh cheeses were salted and held at 16 degrees C for ripening until the pH was reduced to 4.60. Cheeses were then moved into storage at 4 degrees C to complete ripening. During ripening, the E. coli O157:H7 population decreased significantly (P < or = 0.001) and finally was not detectable in Feta cheese after 44 and 36 days and in Telemes cheese after 40 and 30 days for the trials with thermophilic and mesophilic starters, respectively. The estimated times required for one decimal reduction of the population of E. coli O157:H7 after the first day of processing were 9.71 and 9.26 days for Feta cheese and 9.09 and 7.69 days for Telemes cheese for the trials with thermophilic and mesophilic starters, respectively. 相似文献
360.
Georgios Alexandros Skrimpas Thomas Ursin Christian Sweeney Kun Marhadi Nenad Mijatovic Joachim Holboell 《风能》2017,20(8):1389-1404
Faults in planetary gears and related bearings, e.g. planet bearings and planet carrier bearings, pose inherent difficulties on their accurate and consistent detection associated mainly to the low energy in slow rotating stages and the operating complexity of planetary gearboxes. In this work, statistical features measuring the signal energy and Gaussianity are calculated from the residual signals between each pair from the first to the fifth tooth mesh frequency of the meshing process in a multi‐stage wind turbine gearbox. The suggested algorithm includes resampling from time to angular domain, identification of the expected spectral signature for proper residual signal calculation and filtering of any frequency component not related to the planetary stage. Two field cases of planet carrier bearing defect and planet wheel spalling are presented and discussed, showing the efficiency of the followed approach and the possibility of characterizing a fault as localized or distributed. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献