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81.
82.
Tzer-Ming Jeng Sheng-Chung Tzeng Yen-Chan Wang Chao-Hsien Lin 《Heat and Mass Transfer》2008,44(5):527-533
This work experimentally investigates the heat transfer characteristics in the annulus with an inner rotating rib-roughness
cylinder, whose flow and thermal behaviors are associated with Taylor number (Ta) and centrifugal buoyancy parameter (Gr
Ω/Ta). The operating range of Ta is from 4.90 × 102 to 5.80 × 105, while the surface of the inner cylinder is heated up with several constant heat fluxes (279, 425 and 597 W/m2) to obtain various values of Gr
Ω/Ta. Besides, three modes of the inner cylinder without/with longitudinal ribs are considered. The end of the annular channel
is connected to a side chamber to fit practical applications (such as in the rotary blade coupling of a four-wheel-drive vehicle).
The experimental results show that the average Nusselt number
was almost constant at low Ta, but increased rapidly with Ta when Ta exceeded some critical value (3,000–5,200 for present study). Additionally, the Gr
Ω/Ta effect on the heat transfer was negligible herein. Furthermore, by comparing with the inner cylinder without longitudinal
ribs, stalling ribs on the inner cylinder increases the transport of heat by a factor of 1.22 at 105 < Ta < 106, and embedding cavities into the ribs increases the transport of heat by a factor of 1.16 at 105 < Ta < 106. Finally, the relationships between the and the Ta for various modes of test sections were proposed. 相似文献
83.
本文建立了由Lagrange插值公式决定的广义Goppa码最小距离下限扩张的一般定理,它包括了BCH码、广义BCH码和修改RS码的子域子码最小距离下限扩张结果,并对这些结果进行了改进,使其适用性更强.另外,本文还建立了用解线性方程组的方法实现最小距离下限扩张了的广义Goppa码的译码.广义Goppa码是目前较大的一种分组纠错码.因而,本文的结果可应用于现有的所有分组纠错码. 相似文献
84.
Lin T.H. Belser M. Tzeng Y. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1988,16(6):631-637
Gaseous plasma generated by a half-wave rectified power supply are characterized and applied to the etching of photoresist and polymide in oxygen, dry air, or air. Activation energies of 8.6 kcal/mole and 10.9 kcal/mole are calculated for oxygen plasma etching of photoresist and polyimide, respectively. An average power of 625 W at 2.45 GHz is supplied by a magnetron through a rectangular waveguide to a 51-mm diameter quartz tube generating pulsed plasmas in oxygen and nitrogen at pressures between 0.1 torr and 10 torr with a repetitive rate of 60 Hz. The plasmas are studied by a double Langmuir probe and an optical emission spectrometer. Polymers placed in the downstream of the plasma are etched at high rates, especially when external heating is applied to raise the sample temperature. The characteristics of the plasmas and the application to the fast etching of polymers are discussed 相似文献
85.
Yat-Man Choi Lok-Kay Cheng Chih-Hon Tzeng 《International Journal of Infrared and Millimeter Waves》1995,16(9):1561-1571
The modal characteristics of TiLiNbO3 optical channel waveguides depend on its fabrication parameters and were determined empirically. The operating wavelength was 1.55m. Studies and measurements on the mode size of single-mode TiLiNbO3 optical channel waveguides were made for various fabrication parameters. The two-dimensional mode profiles were studied. The Gaussian and Hermite-Gaussian distributions, which were used to calculate the mode sizes, were good approximations for the lateral and vertical intensity distributions of the channel waveguides respectively. Our experimental results were close to those available from literature. 相似文献
86.
The 13C NMR spectra of forty-six cyclic dithioacetals and their derivatives have been studied. A set of shift parameters was established for each of these heterocycles as substituent. Based on the Hammett type correlation for substituted benzenes, the σP +values of cyclic dithioacetal groups have been determined. 相似文献
87.
Richards CI Choi S Hsiang JC Antoku Y Vosch T Bongiorno A Tzeng YL Dickson RM 《Journal of the American Chemical Society》2008,130(15):5038-5039
Single-stranded oligonucleotides stabilize highly fluorescent Ag nanoclusters, with emission colors tunable via DNA sequence. We utilized DNA microarrays to optimize these scaffold sequences for creating nearly spectrally pure Ag nanocluster fluorophores that are highly photostable and exhibit great buffer stability. Five different nanocluster emitters have been created with tunable emission from the blue to the near-IR and excellent photophysical properties. Ensemble and single molecule fluorescence studies show that oligonucleotide encapsulated Ag nanoclusters exhibit significantly greater photostability and higher emission rates than commonly used cyanine dyes. 相似文献
88.
Yixuan Song Elva L. Lugo Stuart Powell Ping Tzeng Benjamin A. Wilhite Jaime C. Grunlan 《Journal of Polymer Science.Polymer Physics》2017,55(23):1730-1737
Multilayer thin films of poly(ethylene oxide) (PEO) and poly(methacrylic acid) (PMAA), deposited via layer‐by‐layer (LbL) assembly from aqueous solutions, are investigated for CO2/N2 separation. Eight and ten bilayer (217 and 389 nm thick, respectively) PEO/PMAA thin films deposited on a 25 μm polystyrene substrate exhibit CO2/N2 selectivities of 142 and 136, respectively. These are the highest reported to‐date for this gas pair separation using a homogeneous polymer film. While further work remains to improve CO2 permeability, these results indicate the potential of LbL assemblies as standalone CO2 separation membranes for low‐flux/high‐purity applications, or as part of a composite and/or mixed‐matrix membrane for high‐flux applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 1730–1737 相似文献
89.
Wen-Hsuan Tseng Dr. Chung-ke Chang Dr. Pei-Ching Wu Prof. Nien-Jen Hu Dr. Gene-Hsiang Lee Dr. Ching-Cherng Tzeng Prof. Stephen Neidle Prof. Ming-Hon Hou 《Angewandte Chemie (International ed. in English)》2017,56(30):8761-8765
Small-molecule compounds targeting trinucleotide repeats in DNA have considerable potential as therapeutic or diagnostic agents against many neurological diseases. NiII(Chro)2 (Chro=chromomycin A3) binds specifically to the minor groove of (CCG)n repeats in duplex DNA, with unique fluorescence features that may serve as a probe for disease detection. Crystallographic studies revealed that the specificity originates from the large-scale spatial rearrangement of the DNA structure, including extrusion of consecutive bases and backbone distortions, with a sharp bending of the duplex accompanied by conformational changes in the NiII chelate itself. The DNA deformation of CCG repeats upon binding forms a GGCC tetranucleotide tract, which is recognized by NiII(Chro)2. The extruded cytosine and last guanine nucleotides form water-mediated hydrogen bonds, which aid in ligand recognition. The recognition can be accounted for by the classic induced-fit paradigm. 相似文献
90.
Gu L Elkin T Jiang X Li H Lin Y Qu L Tzeng TR Joseph R Sun YP 《Chemical communications (Cambridge, England)》2005,(7):874-876
A single-walled carbon nanotube was exploited for its semi-flexible pseudo-one-dimensional nanostructure as a unique scaffold to display multivalent carbohydrate ligands, with a specific demonstration showing that galactosylated carbon nanotubes were effective in the capturing of pathogenic Escherichia coli in solution. 相似文献