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排序方式: 共有237条查询结果,搜索用时 31 毫秒
31.
This investigation explores the mass/heat transfer from a wall-mounted block in a rectangular fully developed channel flow.
The naphthalene sublimation scheme was used to measure the level of local mass transfer from the block’s surfaces. The heat
transfer coefficient can be obtained by analogy between heat and mass transfer. The effects of the Reynolds number on the
local mass transfer from the block’s surfaces have been widely discussed. Results showed that, owing to the flow complexity
induced by vortices around the block, the block’s surfaces appeared four different spatial Sherwood number distributions,
termed “Wave type”, “U type”, “Slant type”, and “Pit type”. A change in the Reynolds number significantly altered the spatial Sherwood number distributions on the block’s surfaces.
Besides, four correlations between the Reynolds number and the surface-averaged Sherwood number were presented for the front,
top, side, and rear surfaces of the block at a given block’s height, for the purpose of practical applications. 相似文献
32.
Tsai-Yu Lin Chien-Wei Wu James C. Chen Y.H. Chiou 《Applied Mathematical Modelling》2011,35(9):4473-4489
Process capability indices provide numerical measures on process reproduction capability, which are effective tools for quality assurance. They are used to realize current situations of the process, and further improve the process problems to assure of product quality to meet the preset capability requirement. For analyzing process capability, most existing methods for assessing process performance were derived based on the traditional frequentist point of view. However, the sampling distributions of the estimated capability indices are usually so complicated, this makes establishing the exact confidence interval very difficult. In this study, we adopt a Bayesian approach to obtain an interval estimation, particularly for the index . Besides, a testing procedure is developed based on the derived results for practitioners to determine whether their manufacturing processes are capable of reproducing products satisfying the preset capability requirement when the manufacturing tolerance is asymmetric or symmetric. 相似文献
33.
Hui-Ling Cheng Shyh-Shin Chiou Yu-Mei Liao Yen-Ling Chen Shou-Mei Wu 《Journal of chromatography. A》2011,1218(15):2114-2120
Two single nucleotide polymorphisms (SNPs) of 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, A1298C and C677T, were widely considered to be related with various neoplasia disorders. We established a simple and effective capillary electrophoresis (CE) method for detection of two SNPs in MTHFR gene simultaneously. DNA samples were amplified by multiplex PCR with universal fluorescence-labeled primer and analyzed by single-strand conformation polymorphism (SSCP)-CE method. The CE method was performed using 1.5% hydroxyethyl cellulose in 1× TBE buffer containing 1 M urea. The PCR products after SSCP procedure were electrokinetically injected at −10 kV, 30 s. Separation voltage was −6 kV and the temperature was set at 20 °C. The optimal SSCP-CE method was applied to detect two polymorphisms in MTHFR gene of acute lymphoblastic leukemia (ALL) and attention-deficit/hyperactivity disorder (ADHD) patients. Genotyping results were evaluated in terms of relationships between outcomes for ADHD patients after ALL chemotherapy and ALL disease. The SSCP-CE method and multiplex PCR with universal fluorescence primer were used as the fast technique for screening two SNPs in MTHFR gene, A1298C and C677T. The genotyping data were coincident with DNA sequencing. This SSCP-CE method was found feasible for detecting mutation of MTHFR gene in populations. 相似文献
34.
Curtis P. Rinsland Linda S. Chiou Aaron Goldman Stephen W. Wood 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,90(3-4):367-375
The average tropospheric volume mixing ratio of CHF2Cl (HCFC-22) has been retrieved from a time series of high spectral resolution ground-based infrared solar absorption spectra recorded with the McMath Fourier transform spectrometer located at the U.S. National Solar Observatory facility on Kitt Peak in southern Arizona (31.9°N, 111.6°W, 2.09 km altitude) for the time period October 1987–November 2002. The retrievals are based on fits to the well-isolated, unresolved 2ν6 Q branch at 829.05 cm−1 and the SFIT2 retrieval algorithm. The measured daily averages show a near linear rise per year in the mean tropospheric volume mixing ratio as a function of time with a best fit yielding an average increase rate of (5.66±0.15) parts per trillion (10−12) by volume per year, corresponding to (6.47±0.17)%yr−1, 1 sigma, at the beginning of the time series. The tropospheric mixing ratios retrieved from the solar spectra have been compared with monthly average surface flask sampling measurements from the Climate Monitoring and Diagnostic Laboratory (CMDL) station at Niwot Ridge, Colorado (40.0°N, 105.5°W, 3013 m altitude), archived measurement from the same location, and early CMDL northern hemisphere Pacific cruise measurements. The average ratio of the retrieved tropospheric mixing ratio relative to the CMDL surface mixing ratio is 1.053 for the overlapping 1987 to 2002 time period. The retrieved mean tropospheric mixing ratio is consistent with the surface measurements within the errors estimated for the remote sensing observations. 相似文献
35.
An Analytic solution is presented of the problem of turbulent heat transfer in pipes with internal heat generation and insulated wall by applying a recently-developed eddy conductivity model. The results agree closely with available experimental data for a wide range of Prandtl number (0.02–10.5). 相似文献
36.
Triulzi RC Micic M Giordani S Serry M Chiou WA Leblanc RM 《Chemical communications (Cambridge, England)》2006,(48):5068-5070
An immunoassay based upon photoluminescent gold quantum dots aimed at detecting human IgG in aqueous solution from micromolar to nanomolar concentrations is described. 相似文献
37.
38.
Efficiency and effectiveness for non-storable commodities represent two distinct dimensions and a joint measurement of both is necessary to fully capture the overall performance. This paper proposes two novel integrated data envelopment analysis (IDEA) approaches, the integrated Charnes, Cooper and Rhodes (ICCR) and integrated Banker, Charnes and Cooper (IBCC) models, to jointly analyze the overall performance of non-storable commodities under constant and variable returns to scale technologies. The core logic of the proposed models is simultaneously determining the virtual multipliers associated with inputs, outputs, and consumption by additive specifications for technical efficiency and service effectiveness terms with equal weights. We show that both ICCR and IBCC models possess the essential properties of rationality, uniqueness, and benchmarking power. A case analysis also demonstrates that the proposed novel IDEA approaches have higher benchmarking power than the conventional separate DEA approaches. More generalized specifications of IDEA models with unequal weights are also elaborated. 相似文献
39.
We propose a novel beam-propagation method (BPM) based on the higher-order Padé approximants in both the transverse and the longitudinal directions. Extending the Padé approximation to the propagation direction and adopting the multistep method increase the programming effort by only a small amount. Compared with the conventional BPM's, this method is more accurate and efficient. The accuracy and the propagation step size are well predicted by a phase analysis. 相似文献
40.
Asokan K Tsai HM Bao CW Chiou JW Pong WF Sonia G Anand TJ 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(2):454-457
X-ray absorption spectroscopic measurements have been used to compare the electronic structures of swift heavy ions (100 MeV Si ions) irradiated and pristine Ni-Al nanocrystalline films. Results from X-ray diffraction (XRD), X-ray absorption near-edge structure (XANES) spectra at Al K-, and Ni L(2,3)-edges and extended X-ray absorption fine structure (EXAFS) at Ni K-edges are discussed. The observed XRD peaks indicate the improvement of crystalline nature and Al(111) clustering after the swift heavy ion interactions. While the XANES spectra at Ni L(2,3)-edges show decrease in the intensity of white line strength, the Al K-edge shows increase in intensity after irradiation. Above results imply that swift heavy ions induce low Z (i.e., Al) ion mass transport, changes in Al sp-Ni-d hybridization, and charge transfer. EXAFS results show that crystalline nature is improved after swift heavy irradiation which is consistent with XRD results. 相似文献