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961.
C. J. E. Straatsma A. Y. Elezzabi 《Journal of Infrared, Millimeter and Terahertz Waves》2011,32(11):1299-1306
We present a metallic resonator fabricated on silicon capable of dual-mode operation at terahertz frequencies. The resonator
exhibits a notch plus stop band filter response or a notch filter response depending on the orientation of the incident electric
field with respect to the structure. The former results in two resonance features: one at 0.69 THz with a Q-factor of 3.7
and the other at 0.91 THz. The latter results in a resonance feature at 0.63 THz with a Q-factor of 5.7. Using 3D finite-difference
time-domain simulations, the resonator is designed to operate between 0.1 and 1.4 THz. Experimental verification is performed
using a free space terahertz time-domain spectroscopy system, and agreement with our simulations is realized. 相似文献
962.
963.
The single-pass (50 cm) amplifier performance of an atmospheric-pressure ArF laser pumped by a 65-ns full-width-at-half-maximum short-pulse electron beam was investigated theoretically for a wide range of excitation rates (0.1-2.0 MW/cm3 ). Atmospheric mixtures of Ne, Ar, and F2 (three mixtures of Ar=40%, 70%, and Ne-free) were studied. A kinetic numerical model of the ArF amplifier with a Ne buffer system was constructed. A one-dimensional propagation treatment considered the gain depletion and saturation absorption spatially and temporally along the optical axis. In this model the rate constants for electron quenching of ArF* of 1.6×10-7, 1.9×10-7, and 2.4×10 -7 cm3/s were used for Ar concentration of 40, 70 percent, and Ar/F2 mixture, respectively 相似文献
964.
Ultrathin sections of raw potato embedded in Spurr's “low viscosity” resin show radial splitting of the starch grains into long bands, presumably evoked when the resin is expanded by hydrocarbon vapor after sectioning. There are no concentric lamellae of starch in these sections, and no evidence of tangentially extended layers of refolded molecules was found. Thus, the principal units of organization in the starch grain are radially extended starch molecules and/or radial fibrillar clusters of these molecules. 相似文献
965.
Direct modulation of an InGaAsP/InP double heterostructure laser was investigated experimentally. Sinusoidal modulation up to 2.5 GHz was achieved with almost constant modulation efficiency. Pulse responses showed that the damped relaxation oscillation in light output was well suppressed. 相似文献
966.
S. Y. Gerlsma 《Starch - St?rke》1970,22(1):3-9
The effect of polyhydric and monohydric alcohols, of phenols, of carboxylic acids and their anions, of halide anions, of alkalimetalions and of some other compounds on the gelatination temperature of potato starch granules in aqueous solutions were studied. Polyhydric alcohols and methanol raise the gelatination temperature, whereas ethanol, propanol, butanol, p-dioxane, carboxylic acids, phenols, urea and hydrogen peroxide cause a decrease in the gelatination temperature. The effect of polyhydric alcohols may be attributed to the lessened tendency of the medium to rupture hydrogen bonds. Carboxylic acids, phenols, urea and hydrogen peroxide may act in a opposite way. The lowering effect of the monohydric alcohols, dioxane, and other non-polar substances may be due to structural and kinetic alterations of the aqueous medium, induced by the non-polar groups. At higher concentrations of ethanol, propanol, p-dioxane, acetic, propionic and butyric acid the gelatination temperature tends to increase. This is to be attributed to the association of solute molecules. 相似文献
967.
Mary F. Barbe Mamta Amin Michele Y. Harris Siva Tejaa Panibatla Soroush Assari Steven N. Popoff Geoffrey M. Bove 《International journal of molecular sciences》2022,23(12)
The effectiveness of manual therapy in reducing the catabolic effects of performing repetitive intensive force tasks on bones has not been reported. We examined if manual therapy could reduce radial bone microstructural declines in adult female Sprague–Dawley rats performing a 12-week high-repetition and high-force task, with or without simultaneous manual therapy to forelimbs. Additional rats were provided 6 weeks of rest after task cessation, with or without manual therapy. The control rats were untreated or received manual therapy for 12 weeks. The untreated TASK rats showed increased catabolic indices in the radius (decreased trabecular bone volume and numbers, increased osteoclasts in these trabeculae, and mid-diaphyseal cortical bone thinning) and increased serum CTX-1, TNF-α, and muscle macrophages. In contrast, the TASK rats receiving manual therapy showed increased radial bone anabolism (increased trabecular bone volume and osteoblast numbers, decreased osteoclast numbers, and increased mid-diaphyseal total area and periosteal perimeter) and increased serum TNF-α and muscle macrophages. Rest, with or without manual therapy, improved the trabecular thickness and mid-diaphyseal cortical bone attributes but not the mineral density. Thus, preventive manual therapy reduced the net radial bone catabolism by increasing osteogenesis, while rest, with or without manual therapy, was less effective. 相似文献
968.
969.
970.
F.J. Liu M.C. Zhang J.X. Dong Y. W. Zhang 《金属学报(英文版)》2007,20(2):102-110
High temperature oxidation behaviors of FGH96 P/M superalloy have been studied in air at temperatures ranging from 600 to 1000℃. By means of isothermal oxidation testing,X-ray diffraction,SEM(scanning electron microscopy),and EDS(energy dispersive X-ray spectroscopy) analyses,the oxidation kinetics as well as the composition and morphology of scales were investigated. Thermodynamic calculations were used to explain the oxidation mechanism. The results showed that as the oxidation temperature increased,the oxidation rate,the scale thickness,and scale spallation increased. FGH96 P/M superalloy exhibits good oxidation resistance at temperature below 800℃. The oxidation kinetics follows an approximately parabolic rate law,and the oxide layer was mainly composed of Cr2O3,TiO2,and a little amount of NiCr2O4. The oxidation is controlled by the transmission of chromium,titanium,and oxygen through the oxide scale. 相似文献