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排序方式: 共有294条查询结果,搜索用时 15 毫秒
71.
Chien-Yie Tsay Kai-Shiung Fan Yu-Wu Wang Chi-Jung Chang Yung-Kuan Tseng Chung-Kwei Lin 《Ceramics International》2010,36(6):1791-1795
Transparent semiconductor ZnO thin films were spin-coated onto alkali-free glass substrates by a sol–gel process. The influence of ZnO sols synthesized via different solvents (2-ME, EtOH or IPA) on the surface morphologies, microstructures, optical properties and resistivities of the obtained films were investigated. The as-coated films were annealed in ambient air at 500 °C for 1 h. X-ray diffraction results showed all polycrystalline ZnO thin films to have preferred orientation along the (0 0 2) plane. The surface morphologies, optical transmittances and resistivity values of the sol–gel derived ZnO thin films depended on the solvent used. The ZnO thin films synthesized with IPA as the solvent exhibited the highest average transmittance 92.2%, an RMS roughness of 4.52 nm and a resistivity of 1.5 × 105 Ω cm. 相似文献
72.
The fatigue crack growth behaviors of AISI 316L stainless steel (SS) welds in air and gaseous hydrogen were evaluated, and further compared with the base plate. In air, the fatigue crack growth rate (FCGR) of the weld after heat-treatment at 1050 oC/1 h was similar to that of the base metal. Furthermore, all specimens became susceptible to hydrogen-accelerated crack growth. Mainly quasi-cleavage fracture related with the strain-induced martensite accounted for the accelerated crack growth in hydrogen. A smaller amount of martensite in the weld was responsible for the decreased susceptibility to hydrogen-enhanced fatigue crack growth relative to the base metal. 相似文献
73.
Qian Feng Ping Yang George W. Kattawar Christina N. Hsu Si-Chee Tsay Istvan Laszlo 《Journal of aerosol science》2009,40(9):776-789
The scattering and radiative properties of mineral dust aerosols at violet-to-blue (0.412, 0.441, and 0.470 μm) and red (0.650 μm) wavelengths are investigated. To account for the effect of particle nonsphericity on the optical properties of dust aerosols, in the present study, these particles are assumed to be spheroids. A combination of the T-matrix method and an improved geometric optics method is applied to the computation of the single-scattering properties of spheroidal particles with size parameters ranging from the Rayleigh to geometric optics regimes. For comparison, the Lorenz–Mie theory is employed to compute the optical properties of spherical dust particles that have the same volumes as their nonspherical counterparts. The differences between the phase functions of spheroidal and spherical particles lead to quite different lookup tables involved in retrieving dust aerosol properties. Moreover, the applicability of a hybrid approach based on the spheroid model for the phase function and the sphere model for the other phase matrix elements is also demonstrated. The present sensitivity study, employing the moderate resolution imaging spectroradiometer (MODIS) measurements and the fundamental principle of the Deep Blue algorithm, illustrates that neglecting the nonsphericity of dust particles usually leads to an underestimate of retrieved aerosol optical depth; although, depending on the scattering angle, an overestimate is noted in some cases. Furthermore, the effect of including full polarization treatment in forward radiative transfer simulation on dust property retrieval is also investigated. It is found that the effect of radiation polarization on the Deep Blue dust property retrieval is not negligible if the retrieval is based on two violet—blue channels centered at 0.412 and 0.470 μm. 相似文献
74.
For Fe/Pt(111) grown at 180 K, the easy axis of magnetization changes from out-of-plane to in-plane while the surface structure changes from fcc(111) to bcc(110). The Curie temperature for 1 ML Fe/Pt(111) is close to room temperature. After insertion of submonolayer Ag, no significant change for the Curie temperature is observed. By thermally annealing Ag/Pt(111) at 550 K to form a Ag-Pt surface alloy, we demonstrate that the Curie temperature of the deposited Fe films is elevated to be higher than room temperature. For an ultrathin Fe/Ag/Fe/Pt(111) sandwich system, the strong interaction between the two Fe layers is superior due to the effect of the double Fe/Ag interfaces. This causes that the easy axis of the magnetization switches back to the in-plane direction during the deposition of Fe overlayer on the surface of a Ag/Fe/Pt(111) film. 相似文献
75.
Journal co-citation analysis of semiconductor literature 总被引:1,自引:0,他引:1
The purpose of this study is to map semiconductor literature using journal co-citation analysis. The journal sample was gathered
from the INSPEC database from 1978 to 1997. In the co-citation analysis, the data compiled were counts of the number of times
two journal titles were jointly cited in later publications. It is assumed that the more two journals are cited together,
the closer the relationship between them. The journal set used was the 30 most productive journals in the field of semiconductors.
Counts of co-citations to the set of semiconductor journals were retrieved from SciSearch database, accessed through Dialog.
Cluster analysis and multi-dimensional scaling were employed to create two-dimensional maps of journal relationships in the
cross-citation networks. The following results were obtained through this co-citation study: The 30 journals fall fairly clearly
into three clusters. The major cluster of journals, containing 17 titles, is in the subject of physics. The second cluster,
consisting of 9 journals, includes journals primarily on material science. The remaining cluster represents research areas
in the discipline of electrical and electronic engineering. All co-cited journals share similar co-citation profiles, reflected
in high positive Pearson correlation. Two hundred and ninety-six pairs (68%) correlate at greater than 0.70. This shows that
there is strong relationship between semiconductor journals. Five individual journals in five paired sets with co-citation
frequency over 100,000 times include Physical Review B, Condensed Matter; Physical Review Letters; Applied Physics Letters; Journal of Applied Physics; and Solid State Communications.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
76.
Transparent semiconductor thin films of Zn1 − xTixO (0 ≦ x ≦ 0.12) were deposited on alkali-free glass substrates by the sol-gel method. The effects of Ti addition on the crystallization, microstructure, optical properties and resistivity of ZnO thin films were investigated. The as-coated films were preheated at 300 °C, and then annealed at 500 °C in air ambiance. X-ray diffraction results showed all polycrystalline Zn1 − xTixO thin films with preferred orientation along the (002) plane. Ti incorporated within the ZnO thin films not only decreased surface roughness but also increased optical transmittance and electrical resistivity. In the present study, the Zn0.88Ti0.12O film exhibited the best properties, namely an average transmittance of 91.0% (an increase of ~ 12% over the pure ZnO film) and an RMS roughness value of 1.04 nm. 相似文献
77.
CC Chen SS Wang SH Tsay FY Lee SL Wu RH Lu FY Chang SD Lee 《Canadian Metallurgical Quarterly》1998,19(3):543-547
The effects of somatostatin and octreotide (a long acting somatostatin analogue) in acute pancreatitis are inconclusive. This study examined the prophylactic and therapeutic effects of different doses of octreotide on retrograde sodium taurodeoxycholate-induced acute necrotizing pancreatitis in rats. The rats were divided into 4 groups receiving subcutaneous injection of saline, octreotide 10 microg/kg, 20 microg/kg at 0, 8 and 16 h and octreotide 20 microg/kg at 5, 13 and 21 h, separately. The serum levels of amylase and lipase, pancreatic histopathology, mortality and hemodynamics were examined. Octreotide significantly reduced serum levels of amylase and lipase at 12 h and the degree of pancreatic edema, necrosis and hemorrhage at 18-24 h as compared to the control group. Prophylactic octreotide 10 microg/kg significantly decreased the 24-h mortality from 100% to 44.4% (p < 0.05). The 24-h mortality further reduced to 12.5% and 10% with prophylactic and therapeutic octreotide 20 microg/kg, respectively. The decrease of mean arterial pressure at 12 h was significantly lower in octreotide groups than in the control group. We conclude that octreotide improves pancreatic histopathology and survival in acute necrotizing pancreatitis in rats. 相似文献
78.
Tsai RH Su FH Chen JP Tsay HL Wen JY Wei TH Huang TM Liao TS 《The Review of scientific instruments》2007,78(11):116104
A novel design is the concept of using charge coupled device camera embedded with calibrated image processing algorithm as a two-dimensional luminance meter to measure the luminance and uniformity of small-scale backlight of unit. A small-scale backlight unit tester was successfully realized and performed to verify this concept. 相似文献
79.
Semiconductor is the key element for information industry. The present study investigated the growth of semiconductor literature based on the database of INSPEC. Well-established bibliometric techniques, such as Bradford-Zipf's plot and Lotka's law have been employed to further explore the characteristics of semiconductor literature. Quantitative results on the literature growth, form of publication, research treatment, publishing country and language, author productivity and affiliate are reported. Moreover, from the Bradford-Zipf's plot, 25 core journals in semiconductor were identified and analyzed. 相似文献
80.
Microsystem Technologies - The objective of this study was to propose a newly-developed method to calculate digital modulation transfer function (DMTF) of digital image system which integrates with... 相似文献