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81.
IntnductionThere are a number of teChniques Presently available for the synthesis of nanopwhcles of oxides and nonokides, includingDndcrowave plasma synthesis['1, plasmaarc synthesisly, and pyrolysis and condensation ofchemical Precursors in the flame at ambient pressureal].The aPProach of uhlizing combushon synthesis toproduce oalde POwders, such as SiO2, A12O3 and TiO2, isalso a quite modem technology['"]. The synthesizedpndcles can be edictly deposited to form a thin film onthe surfac… 相似文献
82.
Numerical simulation for thin wall injection molding of fiber-reinforced thermoplastics 总被引:2,自引:0,他引:2
Y. K. Shen P. H. Yeh J. S. Wu 《International Communications in Heat and Mass Transfer》2001,28(8):1035-1042
The thickness of product is less than 1mm and product compares flowing length to thickness (flow length ratio L/t) to be living above 150 of injection molding filling. This situation is called thin wall injection molding. This study uses MoldFlow software for material (PP), different processing parameters (injection time, melt temperature, mold temperature, injection pressure), various fiber (glass, long glass), different fiber ratio (40%, 50%) and different thickness (1mm, 0.9mm) to simulate the result on notebook computer. The result shows that the mold temperature is the important factor on processing. The mold temperature, melt temperature and injection pressure of thin wall injection molding are higher than convectional injection molding. 相似文献
83.
Kortz H. Cox A. Scott G. Guthals D. Nathel H. Yeh S. Webb S. Clark J. 《Quantum Electronics, IEEE Journal of》1985,21(11):1795-1798
The design and performance of an Nd+3:YAG pumped, short cavity dye laser-dye amplifier system is reported. This system produces narrow bandwidth, broadly tunable picosecond pulses with energies in the millijoule range. 相似文献
84.
Chih-Chung Yang Kung Yeh 《Antennas and Propagation, IEEE Transactions on》1984,32(4):347-355
A wave incident on a volume of random fluctuations of medium parameters will be scattered in all directions. Two kinds of effects on random volume scattering are considered: 1) multiple scattering effect, and 2) Fresnel diffraction effect. The cumulative forward scattering is known to be responsible for the scintillation phenomenon. When strong, such cumulative or multiple scattering can drive the signal statistics into the saturated regime in which the complex amplitudes behave as a complex Gaussian process. These cumulative scattering effects on signals of a bistatic radar are investigated. Additionally, to allow for the possibility that the size of the irregularity is comparable or larger than the first Fresnel zone, Fresnel diffraction instead of Fraunhofer diffraction is considered. A generalized formula for calculating average scattered power, taking both multiple scattering and Fresnel diffraction into account, is derived. It shows that the Fresnel diffraction pattern appearing around the forward direction tends to be smeared out by multiple scattering. Also, both multiple scattering and Fresnel diffraction effects weaken and broaden the forward-scattered beam, and reduce the backscattered power when compared with the single scattering and Fraunhofer diffraction cases respectively. Under certain conditions, the enhancement effect of the backward scattered power is confirmed. 相似文献
85.
86.
H.M. Yeh 《Progress in Nuclear Energy》2009,51(6-7):658-662
The effect of plate aspect ratio on the performance of deuterium recovery from the separation of water–isotope mixture in thermal-diffusion columns of a countercurrent-flow Frazier scheme was investigated. The equations for the optimal plate aspect ratios and the corresponding maximum recovery and maximum production rate were derived. Considerable improvement in performance is obtained when thermal-diffusion columns are operated at the optimal plate aspect ratio. Further improvement can be achieved if the scheme is connected and operated in countercurrent flow, instead of concurrent flow. 相似文献
87.
Li Cui Li-ping Xu Fang-Chang Tsai Ping Zhu Tao Jiang Jen-taut Yeh 《Journal of Polymer Research》2011,18(6):1301-1313
Oxygen scavenging plastic can react with oxygen that was trapped in the packaging materials or permeated into the packages,
and then, extend the shelf life of food contained in packages. Sodium ascorbate (SA) and modified iron (MFe) compounds were
chosen as the main components of oxygen scavengers to prepare the oxygen scavenging LDPE plastics. However, the widely used
hydrophobic LDPE packaging material will slow down the oxygen depletion rate of these oxygen scavenger compounds. So glucose
was used to modify the hydrophobic property of LDPE to improve the oxygen depletion properties of LDPE oxygen scavenging plastic.
The oxygen depletion efficiency of L95[SAx(MFe)y]5 series samples improved initially as the weight ratios of SA/MFe increase, and reached the best as the weight ratios of SA/MFe
approach 7/3. After modifying LDPE with glucoses, the oxygen depletion efficiency of each ML95[SAx(MFe)y]5 specimen improved even better than that of the corresponding L95[SAx(MFe)y]5 specimen with the same loading of oxygen scavenger compound, wherein the oxygen depletion efficiency of ML95[SAx(MFe)y]5 series specimens reached the best as the weight ratios of SA/MFe approach 1/9. In consistent with the oxygen depletion properties
found in the previous section, the peroxide values of modeled food samples tested in the airtight flask with L95[SAx(MFe)y]5 and ML95[SAx(MFe)y]5 series samples reduce consistently as their oxygen depletion properties improve. In order to understand the interesting oxygen
depletion properties of L95[SAx(MFe)y]5 and ML95[SAx(MFe)y]5 series samples, Fourier transform infrared spectroscopy, scanning electron microscope and energy dispersive X-rays analysis
of these samples were performed. 相似文献
88.
Some maize endosperm mutants have branched-chain starch components with long exterior chains which make the blue-value procedure for estimating amylose content questionable. Gel filtration was used to estimate starch composition of normal, high-amylose, waxy and other maize endosperm mutants. Loosely-branched polymers appeared responsible for the apparent amylose content. In some mutants high and intermediate loosely branched polysaccharides were found in addition to amylose. The sweet corn background of some endosperm genotypes influenced the types of polymers produced compared to the dent backgrounds used by previous researchers. 相似文献
89.
Yuh-Ching Gau Tsung-Jang Yeh Chin-Mu Hsu Samuel Yien Hsiao Hui-Hua Hsiao 《International journal of molecular sciences》2022,23(6)
Multiple myeloma is a hematologic malignancy of plasma cells that causes bone-destructive lesions and associated skeletal-related events (SREs). The pathogenesis of myeloma-related bone disease (MBD) is the imbalance of the bone-remodeling process, which results from osteoclast activation, osteoblast suppression, and the immunosuppressed bone marrow microenvironment. Many important signaling cascades, including the RANKL/RANK/OPG axis, Notch signaling, the Wnt/β-Catenin signaling pathways, and signaling molecules, such as DKK-1, sclerostin, osteopontin, activin A, chemokines, and interleukins are involved and play critical roles in MBD. Currently, bisphosphonate and denosumab are the gold standard for MBD prevention and treatment. As the molecular mechanisms of MBD become increasingly well understood, novel agents are being thoroughly explored in both preclinical and clinical settings. Herein, we will provide an updated overview of the pathogenesis of MBD, summarize the clinical management and guidelines, and discuss novel bone-modifying therapies for further management of MBD. 相似文献
90.
Chun-Lang Yeh 《Numerical Heat Transfer, Part A: Applications》2013,63(6):622-645
This study investigates the combustion and fluid flow in a carbon monoxide boiler from the Formosa Petrochemical Corporation in Taiwan, with emphasis on the effect of reburning on NOx reduction. It is found that NOx reduction occurs mainly behind the DeNOx section where recirculation is strong. A smaller reburn hole yields better NOx reduction while a larger reburn hole yields worse NOx reduction and a localized high temperature region near the reburn hole. NOx reduction is better for a lower primary/reburn fuel ratio and a higher inlet/reburn air ratio. A single-reburn-hole arrangement yields lower NOx concentration and temperature than does a three-reburn-hole arrangement. 相似文献