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131.
132.
A sensor with potential for the development of a “chemical barcode” for real-time monitoring of fish freshness is described. This on-package sensor contains a pH sensitive dye, bromocresol green, that responds through visible colour change to basic volatile spoilage compounds, such as trimethylamine (TMA), ammonia (NH3) and dimethylamine (DMA) collectively known as Total Volatile Basic Nitrogen (TVB-N). The sensor characteristics were studied as well as its response with standard ammonia gas. Trials on cod and under-utilised species have verified that the sensor response correlates with bacterial growth patterns in fish samples thus enabling the “real-time” monitoring of spoilage in various fish species. The sensor response can be interrogated with a simple, inexpensive reflectance colorimeter that we have developed based on two light emitting diodes (LEDs) and a photodetector. 相似文献
133.
134.
C. Basavaraja Y. Veeranagouda Kyoung Lee R. Pierson Do Sung Huh 《Journal of Polymer Science.Polymer Physics》2009,47(1):36-45
Conducting polyaniline‐polymannuronate (PANI‐PM) composites were synthesized via in situ deposition techniques. By dissolving different weight percentages of polymannuronate (PM) (5, 10, 15, and 25%), the oxidative polymerization of aniline was achieved through the use of ammonium persulfate as oxidant. Structural morphology, FT‐IR, and X‐ray diffraction (XRD) studies support a strong interaction between PANI and PM. The temperature‐dependent DC conductivity of PANI‐PM composites was studied within the range of 300 ≤ T ≤ 500 °K, presenting evidence for the transport properties of PANI‐PM composites. Conductivity was analyzed through Mott's equation, which leveraged the variable range hopping model in three dimensions. Parameters such as density of states at the Fermi energy, hopping energy, and hopping distance were calculated. Based on the above factors, the synthesis of PANI‐PM composites envisages the future development of biomimetic materials for the creation of a new bionanocomposite as a multicomponent and multifunctional material. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 36–45, 2009 相似文献
135.
June Dong 《Annals of Operations Research》1993,44(2):227-241
In this paper a model of general financial equilibrium with policy interventions is introduced, which yields the optimal composition of assets and liabilities in each sector's portfolio, as well as the market prices for each instrument. The policy interventions considered are taxes and price ceilings. The variational inequality formulation of the equilibrium conditions is derived and then utilized to establish existence and uniqueness properties of the solution pattern. An algorithm is proposed for the computation of the problem. Finally, the algorithm is applied to some special utility functions as numerical examples. 相似文献
136.
Sun Kyu Yang Moon Ki Chung Heung June Chung 《Experimental Thermal and Fluid Science》1992,5(6):828-837
The hydraulic characteristics in subchannels of axially finned rod bundles installed in the Korea Multipurpose Research Reactor (KMRR) were measured using one-component laser-Doppler velocimetry (LDV). Pressure drops for each component, time mean axial velocity, and axial turbulent intensity were measured. Then the friction factors in rod bundles were estimated from the measured pressure drops. The turbulent crossflow mixing rate between neighboring subchannels was evaluated from the measured data. The results show that (1) the friction factors for axially finned rod bundles are less than those given by Moody's correlation for smooth tubes, and (2) as the flow develops, the turbulent crossflow mixing rate between neighboring subchannels decreases and, in the developed region, the values level out. 相似文献
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139.
Jong-Yi Chen Yunshyong Chow June Hsieh 《Journal of Computational and Applied Mathematics》2006,190(1-2):190-199
An infinite homogeneous d-dimensional medium initially is at zero temperature. A heat impulse is applied at the origin, raising the temperature there to a value greater than a constant value u0>0. The temperature at the origin then decays, and when it reaches u0, another equal-sized heat impulse is applied at a normalized time τ1=1. Subsequent equal-sized heat impulses are applied at the origin at the normalized times τn, n=2,3,…, when the temperature there has decayed to u0. This sequence of normalized waiting times τn can be defined recursively by a difference equation and its asymptotic behavior was known recently. This heat conduction problem was first studied in [J. Difference Equations Appl. 3 (1997) 89–91].
A natural subsequent question is what happens if the problem is set in a finite region, like in a laboratory, with the temperature at the boundary being kept zero forever. In this paper we obtain the asymptotic behavior of the heating times for the one-dimensional case. 相似文献
140.
We study self-dual vortex solutions in a Maxwell – Chern – Simons model with anomalous magnetic moment. We establish the existence
of multivortex solutions and obtain the quantized energy and the magnetic flux. We also prove the uniqueness of solutions
when there is only one vortex point.
相似文献