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排序方式: 共有241条查询结果,搜索用时 15 毫秒
11.
Jianding Yu Yan Liu Xiuhong Pan Hongyang Zhao Velu Nirmal Kumar Mukannan Arivanandhan Yoshimi Momose Yasuhiro Hayakawa Xingwang Zhang Xinghong Luo Yasuhiro Okano Yuko Inatomi 《Microgravity science and technology》2016,28(2):143-154
The paper reviewed the previous microgravity experiment using Chinese recovery satellite, the in-situ measurement of composition profile in the solution by X-ray penetration method and homogeneous growth of InGaSb by temperature freezing method under terrestrial condition for making clear the effect of gravity on the growth of InGaSb ternary alloy semiconductor crystals. The previous experimental results showed that the shape of solid/liquid interfaces and composition profile in the solution were significantly affected by gravity. Based on the previous microgravity experimental results, experimental conditions were investigated to grow homogeneous In xGa 1?xSb with higher indium composition at Chinese recovery satellite SJ-10 in near future. 相似文献
12.
Although the majority of patients with pituitary tumor, undergoing transsphenoidal microsurgery, have a low incidence of hormonal deficiency after surgery, the endocrinological evaluations should be carefully done before and after surgery. Glucocorticoid replacement is necessary in patients with Cushing's disease during and after surgery as well as those with adrenal insufficiency. Repeated CRF test is useful to assess the secondary adrenal insufficiency of Cushing's disease after surgery. Patients with impaired secretion of both ACTH and TSH should receive glucocorticoid replacement before thyroid hormone replacement in order to avoid adrenal crisis. A combination of CRF, GRF, TRH and GnRH is a safer and more reliable test to evaluate pituitary function than the conventional triple test consisting of insulin, TRH and GnRH, especially in patients predicted to have pituitary-adrenal insufficiency. Diabetes insipidus(DI), immediately after pituitary surgery, should be treated with subcutaneous injection of Pitressin. Even if patients seem to have recovered from DI several days after surgery, they must be monitored closely because of the incidence of triphasic DI. Less attention has been given to replacement for GH deficiency in adults. Recent reports revealed that GH replacement in adults with GH deficiency decreases visceral fat tissue and increases plasma calcium, phosphorus, osteocalcin and procollagen III levels. GH replacement will become more popular even in adults. Many options and technological advantages in the diagnosis and treatment of pituitary tumors have developed in a decade. In the near future, post-operative patients with pituitary tumors must be cared for in view of the "quality of life". 相似文献
13.
Zuogui Zhang Yoshimi Watanabe Icksoo Kim Xiangfa Liu 《Metallurgical and Materials Transactions A》2005,36(13):837-844
Refining experiments were conducted to evaluate the grain refining performance of an Al−5Ti−0.25C refiner before and after
equal-channel angular pressing (ECAP) with the use of a high-purity Al. The results show that the Al−5Ti−0.25C refiner has
remarkable and stable grain refining performance when the holding times are within 5 to 30 minutes and the melt temperatures
are within 1003 to 1073 K. Furthermore, some Al−5Ti−0.25C refiner samples were subjected to severe plastic deformation by
using the ECAP technique at 298 K. It was found that Al3Ti and TiC particles were significantly fragmented and their mean sizes were decreased to 10 and 1.08 μm, respectively, and
the Al−5Ti−0.25C refiner appeared to have a double grain refining effect in comparison with that of before ECAP. It is also
testified that the Vickers microhardness (Hv) value of the pure Al samples refined by the Al−5Ti−0.25C refiner after ECAP
processing has a significant increment than that of before ECAP processing. It is concluded that the Al−5Ti−0.25C refiner
with ECAP technique has a very useful practical application in refining industrial Al alloys.
ZUOGUI ZHANG, formerly Master's Student, the Key Laboratory of Liquid Structure and Heredity of Material, Ministry of Education,
Shandong University, Jinan 250061, People's Republic of China 相似文献
14.
Noriaki Murakami Koji Arafune Tadanobu Koyama Yoshimi Momose Tetsuo Ozawa Yasunori Okano Sadik Dost Le. H. Dao Masashi Kumagawa Yasuhiro Hayakawa 《Microgravity science and technology》2005,16(1-4):79-83
The effect of gravity on dissolution of GaSb in InSb melt and growth of InGaSb was experimentally investigated. Experiments were carried out in a GaSb(seed)/InSb/GaSb(feed) sandwich system under an imposed temperature gradient. In the experiments, the GaSb feed crystal dissolved into the InSb melt to supply the required GaSb component for the growth of In0.1Ga0.9Sb crystal. Two parameters were considered: (1) the inclination angle (θ) of the sample for gravity as 0° and 53°, and (2) the sample diameter (D) as 9 mm and 5mm. When θ was 0°, the interface was almost flat, indicating that convection was axisymmetric and stable. Whereas the interface was distorted towards gravitational direction when θ was 53°, indicating that solutal convection was dominant. The decrease of growth temperature and sample diameter reduced the distortion of interface and the dissolution amount of GaSb feed. The homogeneous crystals were grown at the initial growth stage by supplying the GaSb component during growth. 相似文献
15.
Shinya Kato Yasuyoshi Kurokawa Yuya Watanabe Yasuharu Yamada Akira Yamada Yoshimi Ohta Yusuke Niwa Masaki Hirota 《Nanoscale research letters》2013,8(1):216
Silicon nanowire (SiNW) arrays were prepared on silicon substrates by metal-assisted chemical etching and peeled from the substrates, and their optical properties were measured. The absorption coefficient of the SiNW arrays was higher than that for the bulk silicon over the entire region. The absorption coefficient of a SiNW array composed of 10-μm-long nanowires was much higher than the theoretical absorptance of a 10-μm-thick flat Si wafer, suggesting that SiNW arrays exhibit strong optical confinement. To reveal the reason for this strong optical confinement demonstrated by SiNW arrays, angular distribution functions of their transmittance were experimentally determined. The results suggest that Mie-related scattering plays a significant role in the strong optical confinement of SiNW arrays. 相似文献
16.
Shinya Kato Yasuyoshi Kurokawa Shinsuke Miyajima Yuya Watanabe Akira Yamada Yoshimi Ohta Yusuke Niwa Masaki Hirota 《Nanoscale research letters》2013,8(1):361
To achieve a high-efficiency silicon nanowire (SiNW) solar cell, surface passivation technique is very important because a SiNW array has a large surface area. We successfully prepared by atomic layer deposition (ALD) high-quality aluminum oxide (Al2O3) film for passivation on the whole surface of the SiNW arrays. The minority carrier lifetime of the Al2O3-depositedSiNW arrays with bulk silicon substrate was improved to 27 μs at the optimum annealing condition. To remove the effect of bulk silicon, the effective diffusion length of minority carriers in the SiNW array was estimated by simple equations and a device simulator. As a result, it was revealed that the effective diffusion length in the SiNW arrays increased from 3.25 to 13.5 μm by depositing Al2O3 and post-annealing at 400°C. This improvement of the diffusion length is very important for application to solar cells, and Al2O3 deposited by ALD is a promising passivation material for a structure with high aspect ratio such as SiNW arrays. 相似文献
17.
The local structure of trace amounts of lead in an adsorbent matrix that contains a high concentration of iron and magnesium (Mg6Fe2(OH)16(CO3) x 3H2O) was successfully monitored by means of X-ray absorption fine structure spectroscopy combined with fluorescence spectrometry. A eutectic mixture of PbCO3 and Pb(OH)2 coagulated when Pb2+ was adsorbed from a 1.0 ppm aqueous solution, and in contrast, the major species was ion-exchanged Pb2+ in the case of adsorption from a 100 ppb aqueous solution. The difference was ascribed to the balance between the precipitation equilibrium for coagulation and the rate of the ion exchange reaction with surface hydroxyl groups. 相似文献
18.
Potentiometric pH-stat titration was performed on alkylated carbon black dispersed in aqueous solution at pH 9.0, 10.0 and 11.0 and alkaline hydrolysis rate constant of the alkylated functional groups on the carbon black was obtained therefrom. Carbon black treated with C1-C8n-alcohols in vapor or liquid phase was used in this experiment. Hydrolysis proceeded more rapidly for carbon black treated with lower alcohols. For each alkylated carbon black, the hydrolysis rate constant decreased with time and, after the hydrolysis rate diminished, a hydrolysis resistant fraction of alkylated groups remained. For example, the hydrolysis rate constants at 25°C were 24.33, 17.50 and 4.501 · mol?1 · sec?1 at 15 min and 6.00, 6.00 and 3.671 · mol?1 · sec?1 at 45 min after the start of hydrolysis at pH 9.0 for carbon black treated with C2, C3 and C4 alcohols respectively. 相似文献
19.
20.
S.C. Ferreira L.A. Rocha E. Ariza P.D. Sequeira Yoshimi Watanabe J.C.S. Fernandes 《Corrosion Science》2011,(6):2058-2065
Intermetallic particles, Al3Ti and Al3Zr were formed in Al–5mass%Ti and Al–5mass%Zr alloys, respectively, by centrifugal casting, in order to create functionally graded materials (FGMs). At present, no information is available on the influence of the amount of intermetallics on the electrochemical properties of these alloys.In this paper, the corrosion resistance of Al/Al3Ti and Al/Al3Zr FGMs was investigated by open-circuit measurements, potentiodynamic polarization and electrochemical impedance spectroscopy. Results suggests that the corrosion resistance of the FGMs is affected by galvanic effects between the intermetallic particles and the metallic matrix. Lower centrifugal forces resulted in an improvement of the electrochemical properties. 相似文献