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Structure Suitable (structure + suitable)
Selected AbstractsAn Efficient Asymmetric Synthesis of 2-Substituted 1,4-Benzodiazepin-3-one as a Potential Molecular ScaffoldEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 8 2005Nuria Cabedo Abstract 2-Substituted 1,4-benzodiazepine-2-one compounds (9,12) were obtained by a highly diastereoselective alkylation of a seven-membered ring benzolactam (8) in the presence of (R)-phenylglycinol as a chiral inductor. The corresponding acid derivative (16) afforded a conformationally constrained structure suitable for preparing peptidomimetic analogues useful as a novel molecular scaffold. After cleavage of the chiral appendage this approach might also lead efficiently to enantiomerically pure 2-substituted benzodiazepines (15). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Theoretical analysis on thermoelectric power generation with rectangular-fin elements and its applicability in micro systemsHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 3 2006Yutaka Oda Abstract A thermoelectric module, which consists of rectangular-fin elements and has a simple structure suitable for micro fabrication, was newly proposed for a micro- to milli-scale thermoelectric power generator. A unit model was introduced to examine the basic characteristics of thermoelectric power generation with rectangular-fin elements. Theoretical descriptions of the power density and conversion efficiency were given by solving one-dimensional heat and current flows inside the elements. Then, it was found that there exist optimum aspect ratios of the elements to achieve maximum power density and conversion efficiency. Power density becomes larger if the module is downsized with a similarity in shape, while conversion efficiency remains constant, i.e., smaller devices show better performance. Finally, comparative analysis with a standard pi-type module was conducted to emphasize the superiority of the proposed module in micro systems, when convective heat transfer resistance is taken into account. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(3): 224,244, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20108 [source] Characterization of the common mode rejection ratio of amorphous silicon balanced photodiodePHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3-4 2010D. Caputo Abstract In this work we report on the detailed characterization of an amorphous silicon/amorphous silicon carbide balanced photodiode structure suitable for differential photocurrent measurements. The device is a three-terminal structure constituted by two series-connected amorphous silicon p-i-n photodiodes. Two terminals are used to bias the two photodiodes at the same reverse voltage by the readout electronics. The output signal is the current difference between the two diodes, measured at the third terminal with a transimpedance circuit. Several devices have been fabricated with different areas and geometries utilizing four mask-step process. The devices have been characterized by means of common mode rejection ratio (CMRR) measurements as a function of the radiation wavelength and intensity. The CMRR measured under white light illumination has been found to lie around 37 dB in the whole range of investigated radiation intensities. The decrease of the CMRR observed at shorter wavelengths has been ascribed to mismatches and inhomogeneities in the surface and in the p-type window layer of the two hemi-devices. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Implications of spatial variability of fish assemblages for monitoring of Australia's tropical estuariesAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2010Marcus Sheaves Abstract 1. Although often seen as ideal targets for monitoring environmental change because of their high public profile, fish assemblages rarely appear as indicators in monitoring and reporting. 2. Published data were evaluated to develop a simple approach to quantifying the temporal consistency in assemblage structure suitable for routine monitoring and assessment. Data were examined as catch per unit effort (CPUE) and probability of encounter (PoE), and compared using three approaches with the potential to produce simple indices quantifying the patterns of similarity within an estuary over time: species richness, Bray-Curtis Similarities and a new approach, DeltaPoE. Indices derived from published data were then tested against a time series of data from two estuarine lakes with a history of fish kills. 3. Multidimensional scaling based on PoE emphasizes the temporal consistency of fish assemblages within estuaries at least as well as one based on mean CPUE while providing operational advantages. Similarities based on PoE were more sensitive to change from ,natural' assemblage structure than the simpler indices and showed comparable results with Similarities from (log) CPUE data. The one drawback to Similarities is that their complex statistical formulation often makes them less effective vehicles for reporting and communication. Where this is the case the conceptual simplicity of DeltaPoE and its performance relative to Similarities suggests it is a good candidate from which to develop monitoring indices suitable for routine reporting. 4. The performance of each of the indices were considered against the known fish kills. Species richness tracked the observed changes, an expected outcome in this case because a major impact directly removed species. Both indices based on Similarities also tracked the changes faithfully. Of the two, Similarities based on PoE seemed to react more strongly to assemblage changes. Copyright © 2010 John Wiley & Sons, Ltd. [source] Cover Picture: Fabrication of Stable Metallic Patterns Embedded in Poly(dimethylsiloxane) and Model Applications in Non-Planar Electronic and Lab-on-a-Chip Device Patterning (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 4 2005Mater. Abstract A composite image is shown that highlights examples of device architectures that either incorporate or exploit polymer-embedded metallic microstructures. In work reported by Nuzzo and co-workers on p.,557, new applications of soft lithography, in conjunction with advanced forms of multilayer metallization, are used to construct these exceptionally durable structures. They are suitable for use in non-planar lithographic patterning, and as device components finding applications ranging from microelectronics to Lab-on-a-Chip analytical systems. This article describes the fabrication of durable metallic patterns that are embedded in poly(dimethylsiloxane) (PDMS) and demonstrates their use in several representative applications. The method involves the transfer and subsequent embedding of micrometer-scale gold (and other thin-film material) patterns into PDMS via adhesion chemistries mediated by silane coupling agents. We demonstrate the process as a suitable method for patterning stable functional metallization structures on PDMS, ones with limiting feature sizes less than 5,,m, and their subsequent utilization as structures suitable for use in applications ranging from soft-lithographic patterning, non-planar electronics, and microfluidic (lab-on-a-chip, LOC) analytical systems. We demonstrate specifically that metal patterns embedded in both planar and spherically curved PDMS substrates can be used as compliant contact photomasks for conventional photolithographic processes. The non-planar photomask fabricated with this technique has the same surface shape as the substrate, and thus facilitates the registration of structures in multilevel devices. This quality was specifically tested in a model demonstration in which an array of one hundred metal oxide semiconductor field-effect transistor (MOSFET) devices was fabricated on a spherically curved Si single-crystalline lens. The most significant opportunities for the processes reported here, however, appear to reside in applications in analytical chemistry that exploit devices fabricated using the methods of soft lithography. Toward this end, we demonstrate durably bonded metal patterns on PDMS that are appropriate for use in microfluidic, microanalytical, and microelectromechanical systems. We describe a multilayer metal-electrode fabrication scheme (multilaminate metal,insulator,metal (MIM) structures that substantially enhance performance and stability) and use it to enable the construction of PDMS LOC devices using electrochemical detection. A polymer-based microelectrochemical analytical system, one incorporating an electrode array for cyclic voltammetry and a microfluidic system for the electrophoretic separation of dopamine and catechol with amperometric detection, is demonstrated. [source] Layered coding for satellite-plus-terrestrial multipath correlated fading channelsINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 5 2004A. Levissianos Abstract This paper introduces two alternative layered-coding (LC) structures suitable for a combination of a geostationary (GEO) satellite and a terrestrial system providing multicasting multimedia services. Both schemes include a RAKE receiver and their performance results are presented under realistic satellite and terrestrial channel conditions. The structures are based on mapping the coded bits either onto 8-PSK symbols or onto QPSK symbols. The LC parameters (such as the interleaver design and the convolutional encoder structures) are analysed and their effect on performance is quantified, especially in cases of highly correlated channels (low vehicular speeds). The various impairments that are associated to the transmission through both terrestrial and satellite correlated fading channels will be taken into account and link level performance results as well as a complexity discussion will be presented. Copyright © 2004 John Wiley & Sons, Ltd. [source] | ||||||||||