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631.
FS Balcells JA de Torres Mateos AG Mas FG Lopes 《Canadian Metallurgical Quarterly》1976,82(6):385-395
Extravasation of urine was seen in 24 intravenous pyelograms taken for renal colic during the year 1973-74. A number of the patients presented with an acute abdomen. Extravasation took place of retained urine under pressure in the renal pelvis with leakage either around the clayces, from a fissure in the pelvis or even around the ureter. Extravasations of this type are in general rabsorbed without trace. In 5 cases, operation was necessary to drain a purulent collection which had developed in association with the extravasated urine. 相似文献
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Terahertz time-domain measurement of ballistic electron resonance in a single-walled carbon nanotube
Understanding the physics of low-dimensional systems and the operation of next-generation electronics will depend on our ability to measure the electrical properties of nanomaterials at terahertz frequencies ( approximately 100 GHz to 10 THz). Single-walled carbon nanotubes are prototypical one-dimensional nanomaterials because of their unique band structure and long carrier mean free path. Although nanotube transistors have been studied at microwave frequencies (100 MHz to 50 GHz), no techniques currently exist to probe their terahertz response. Here, we describe the first terahertz electrical measurements of single-walled carbon nanotube transistors performed in the time domain. We observe a ballistic electron resonance that corresponds to the round-trip transit of an electron along the nanotube with a picosecond-scale period. The electron velocity is found to be constant and equal to the Fermi velocity, showing that the high-frequency electron response is dominated by single-particle excitations rather than collective plasmon modes. These results demonstrate a powerful new tool for directly probing picosecond electron motion in nanostructures. 相似文献
638.
Claudia R da Luz Humberto Nicastro Nelo E Zanchi Daniela FS Chaves Antonio H Lancha Jr 《Journal of the International Society of Sports Nutrition》2011,8(1):1-4
Branched-chain amino acids (BCAA) supplementation has been considered an interesting nutritional strategy to improve skeletal muscle protein turnover in several conditions. In this context, there is evidence that resistance exercise (RE)-derived biochemical markers of muscle soreness (creatine kinase (CK), aldolase, myoglobin), soreness, and functional strength may be modulated by BCAA supplementation in order to favor of muscle adaptation. However, few studies have investigated such effects in well-controlled conditions in humans. Therefore, the aim of this short report is to describe the potential therapeutic effects of BCAA supplementation on RE-based muscle damage in humans. The main point is that BCAA supplementation may decrease some biochemical markers related with muscle soreness but this does not necessarily reflect on muscle functionality. 相似文献
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Matthew J. Dejneka Christy Powell Nick Borrelli Dimitre Ouzounov Alex Gaeta 《Journal of the American Ceramic Society》2005,88(9):2435-2441
Transparent magnetic glass-ceramics were produced by infiltrating nano-porous glass with nitrate salts and firing. The resultant glass-ceramics contained spinel ferrite nanocrystals that exhibited ferromagnetic and superparamagnetic behavior depending on composition and firing temperature. Transparency in the near infrared was obtained when oxidizing conditions were used to prevent Fe2+ formation, while the porous matrix ensured nano-sized crystallites to limit scattering losses. MnFe2 O4 glass-ceramics treated at 1000°C offered the best combination of magnetic and optical properties with a saturation magnetization of 5.6 emu/g, a Verdet constant of 16.5°/cm, and losses below 3 dB/mm at 1550 nm. 相似文献