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101.
Synthesis of titanium oxide film by plasma oxidization of the metallic films is investigated. Argon/oxygen gas mixture in the pressure range 30 × 10?2 mbar is used for plasma processing at a frequency of 250 kHz. The plasma‐oxidized films are annealed in a tube furnace in argon atmosphere to establish crystalline‐phase formation. X‐ray diffraction and Raman spectroscopic results manifest peaks corresponding to rutile TiO2. Ultraviolet‐Visible (UV‐Vis) spectroscopic analysis confirms the bandgap of rutile TiO2, and photoluminescence spectra exhibit peaks due to oxygen defects. Homogeneity across the film's thickness and the nature of the film substrate interface is studied by depth profiling acquired using secondary ion mass spectrometry. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
102.
We report both the experimental and theoretical insights of differential electro‐diffusion behavior of carbon nanomaterials (e.g. single wall, multiwall carbon nanotubes, and graphene). We thus discriminate one from the other in a soft gel system. The differential mobility of such material depends on their intrinsic properties, both extend and rate of migration bearing the discriminatory signature. The mobility analysis is made by a real time monitoring of the respective bands.  相似文献   
103.
Reaction of [RuIII(EDTA)(CyS)]2? (edta4? = ethylenediaminetetraacetate; CySH = cysteine) with molecular oxygen (O2) has been studied as a function of pH (4.0–8.0) and cysteine concentration (0.2–2.0 mM) at room temperature (25 °C). Biological activities of the [Ru(EDTA)]/CySH/O2 system pertaining to cleavage of supercoiled plasmid DNA to its nicked open circular form has been explored in this work. Results are discussed in regard to the reaction of the ruthenium(III)-complex with molecular oxygen) and a working mechanism is proposed for the biological activities of the ruthenium(III)-complex in the presence of O2.  相似文献   
104.
Organometallic metal(arene) anticancer agents require ligand exchange for their anticancer activity and this is generally believed to confer low selectivity for potential cellular targets. However, using an integrated proteomics-based target-response profiling approach as a potent hypothesis-generating procedure, we found an unexpected target selectivity of a ruthenium(arene) pyridinecarbothioamide (plecstatin) for plectin, a scaffold protein and cytolinker, which was validated in a plectin knock-out model in vitro. Plectin targeting shows potential as a strategy to inhibit tumor invasiveness as shown in cultured tumor spheroids while oral administration of plecstatin-1 to mice reduces tumor growth more efficiently in the invasive B16 melanoma than in the CT26 colon tumor model.  相似文献   
105.
Summary The development of a compressible boundary layer over a wedge impulsively set into motion is studied in this paper. The initial motion is independent of the leading edge effect and the solutions are those of a Rayleigh-type problem. The motion tends to an ultimate steady state of Falkner-Skan type. The equations governing the transient boundary layer from the initial steady state to the terminal steady-state change their character after certain time due to the leading edge effect and thereafter solution depends on both the end conditions. Numerical solutions are obtained through the second-order accuracy upwind scheme. The effects of the Falkner-Skan parameter and the surface temperature on the transient flow and heat transfer are also studied. It has been found that the flow separation does not occur form–0.0707 when w = 1.5 (hot wall), andm–0.118 when 0.5 (cold wall).  相似文献   
106.
Electronic nose systems when deployed in network mesh can effectively provide a low budget and onsite solution for the industrial obnoxious gaseous measurement. For accurate and identical prediction capability by all the electronic nose systems, a reliable calibration transfer model needs to be implemented in order to overcome the inherent sensor array variability. In this work, robust regression (RR) is used for calibration transfer between two electronic nose systems using a Box–Behnken (BB) design. Out of the two electronic nose systems, one was trained using industrial gas samples by four artificial neural network models, for the measurement of obnoxious odours emitted from pulp and paper industries. The emissions constitute mainly of hydrogen sulphide (H2S), methyl mercaptan (MM), dimethyl sulphide (DMS) and dimethyl disulphide (DMDS) in different proportions. A Box–Behnken design consisting of 27 experiment sets based on synthetic gas combinations of H2S, MM, DMS and DMDS, were conducted for calibration transfer between two identical electronic nose systems. Identical sensors on both the systems were mapped and the prediction models developed using ANN were then transferred to the second system using BB–RR methodology. The results showed successful transmission of prediction models developed for one system to other system, with the mean absolute error between the actual and predicted concentration of analytes in mg L−1 after calibration transfer (on second system) being 0.076, 0.1801, 0.0329, 0.427 for DMS, DMDS, MM, H2S respectively.  相似文献   
107.
A Resistive Random Access Memory (RRAM), where the memory performance principally originated from ‘resistive’ change rather than ‘capacitive’ one (the case with conventional CMOS memory devices), has attracted researchers across the globe, owing to its unique features and advantages meeting the demands of future generation high-speed, ultra low power, nano dimensional memory devices. A large family of semiconducting oxides have been investigated as insulator for Resistive Random Access Memory (RRAM), amongst which TiO2 is one of the potential candidate, principally owing to some of its remarkable advantages e.g. wide band gap, high temperature stability and high dielectric constant with flexibility to offer both unipolar and bipolar switching, which are essential for RRAM device applications. In this review article, we tried to represent the long voyage of TiO2 based RRAM, towards the improvement of the reliability aspects of the device performance in a comprehensive manner. Starting with the key factors like oxygen vacancies, Ti interstitials and electroforming, which are responsible for resistive switching phenomenon, various material preparation techniques for RRAM development have been discussed with emphasis on relative merits and bottlenecks of the process. The factors like electrode material and geometry, device structuring, doping, compliance current, annealing effect etc., which play the pivotal role in determining the switching performance of the device, have been reviewed critically. Finally, the article concludes with the comparison of different TiO2 based RRAM devices followed by the prediction of possible future research trends.  相似文献   
108.
In this paper, we first consider the problem of determining the robust positivity of a real function f(x) as the real vector x varies over a box XRl. We show that, it is sufficient to check a finite number of specially constructed points. This is accomplished by using some results on sign-definite decomposition. We then apply this result to determine the robust Hurwitz stability of a family of complex polynomials whose coefficients are polynomial functions of the parameters of interest. We develop an eight polynomial vertex stability test that is a sufficient condition of Hurwitz stability of the family. This test reduces to Kharitonov’s well known result for the special case where the parameters are just the polynomial coefficients. In this case, the result is tight. This test can be recursively and modularly used to construct an approximation of arbitrary accuracy to the actual stabilizing set. The result is illustrated by examples.  相似文献   
109.
Tools for designing signal processing systems with their semantic foundation in dataflow modeling often use high-level graphical user interfaces (GUIs) or text based languages that allow specifying applications as directed graphs. Such graphical representations serve as an initial reference point for further analysis and optimizations that lead to platform-specific implementations. For large-scale applications, the underlying graphs often consist of smaller substructures that repeat multiple times. To enable more concise representation and direct analysis of such substructures in the context of high level DSP specification languages and design tools, we develop the modeling concept of topological patterns, and propose ways for supporting this concept in a high-level language. We augment the dataflow interchange format (DIF) language—a language for specifying DSP-oriented dataflow graphs—with constructs for supporting topological patterns, and we show how topological patterns can be effective in various aspects of embedded signal processing design flows using specific application examples.  相似文献   
110.
A simple synthesis of a targeted drug delivery system with enhanced cytotoxicity to (epidermal growth factor receptor) EGFR(+) cancer cells.  相似文献   
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