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21.
Carbon Nanotubes: Simple Salt‐Coordinated n‐Type Nanocarbon Materials Stable in Air (Adv. Funct. Mater. 18/2016)
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22.
浸没式光刻的优势和可行性 总被引:3,自引:2,他引:3
SoichiOwa HiroyukiNagasaka 《电子工业专用设备》2004,33(2):10-14,18
浸没式光刻通过高折射率的液体充入透镜底部和片子之间的空间使光学系统的数值孔径具有显著的优势。在193nm曝光系统中,水(折射率为1.44)被选作最佳的浸入液体。通过成像模拟,现已证明ArF穴193nm雪浸没式光刻(NA=1.05~1.23)与F2穴157nm雪干法穴NA=0.85~0.93雪光刻具有几乎相同的成像性能。结合流体力学和热模拟结果,讨论了ArF浸没式曝光设备的优势和可行性。 相似文献
23.
Construction of an error map of rotary axes on a five-axis machining center by static R-test 总被引:1,自引:0,他引:1
Soichi Ibaraki Chiaki OyamaHisashi Otsubo 《International Journal of Machine Tools and Manufacture》2011,51(3):190-200
This paper proposes an efficient and automated scheme to calibrate error motions of rotary axes on a five-axis machining center by using the R-test. During a five-axis measurement cycle, the R-test probing system measures the three-dimensional displacement of a sphere attached to the spindle in relative to the machine table. Location errors, defined in ISO 230-7, of rotary axes are the most fundamental error factors in the five-axis kinematics. A larger class of error motions can be modeled as geometric errors that vary depending on the angular position of a rotary axis. The objective of this paper is to present an algorithm to identify not only location errors, but also such position-dependent geometric errors, or “error map,” of rotary axes. Its experimental demonstration is presented. 相似文献
24.
25.
An improved method for sulfur chemiluminescence detection in combination with capillary gas chromatography was established. The method was applied to the analysis of a sulfur-containing antiasthma drug, S-1452, and its nine metabolities in human plasma. The high selectivity and sensitivity of the method allowed accurate quantitation of trace levels of these compounds in human plasma with no interferences from the biological components present. To enable stable measurements and maintain reproducibility over a long period, the performance characteristics of a commercially available instrument were investigated. The gas seal in the injection port was found to easily corrode through interaction of the sulfur analyte with the metal gas seal. To prevent this, a disk made from an alloy of platinum and gold (60:40) was mounted on the gas seal. The reproducibility of the measurement was improved remarkably by using the disk. The use of compressed air of high purity significantly lowered the signal-to-noise ratio. The optical filter was kept clean by using a nickel catalyst to trap ozone in place of copper manganese oxide (CuMn2O4). These improvements raised the sensitivity and selectivity with the lower quantitation limits of 0.5-1.0 ng/mL in human plasma. 相似文献
26.
A. Matsubara K. Kawasaki H. Inaba S. Miyawaki O. Ishikawa T. Hata T. Kodama 《Journal of Low Temperature Physics》1999,114(3-4):349-370
We have measured the viscosity, , and the slip length, , of normal and superfluid
3
He using a torsional oscillator with a thick sample space. We coated the oscillating surface with 2.5 layers of
4
He film to study how the
4
He thin film changes the scattering mechanism of
3
He quasiparticles at the cell wall at 5 bar and 21 bar. In the normal phase, the temperature dependence of the viscosity was changed a little by the
4
He film at 21 bar but no change was observed at 5 bar. The slip length was enhanced by
4
He coating at 5 bar. This enhancement indicates the increase of specularity of
3
He quasiparticles scattering at the oscillating surface. On the other hand, a reduction of the slip length was observed at 21 bar. In the superfluid phase, the temperature dependence of supports the existence of Andreev reflection even with
4
He film on the surface at 5 bar and 21 bar. 相似文献
27.
H Shimada K Nakajima T Ochiai Y Koide SI Okazumi H Matsubara A Takeda Y Miyazawa M Arima K Isono 《Canadian Metallurgical Quarterly》1998,5(4):871-874
The significance of serum p53-Abs in patients with esophageal squamous cell carcinoma was determined. Examination of clinicopathological features and assessment of tumor marker sensitivities of carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC-Ag) and CYFRA21-1 were performed. Thirty-three (58%) of 57 patients were positive for serum p53-Abs, however, no relation with cancer progression existed. Fourteen of the 33 sero-positive patients revealed normal levels of all tumor markers tested. Thus, serum p53-Abs appears to be a useful marker for the detection of esophageal squamous cell carcinoma. 相似文献
28.
Y Nagai T Azuma M Funauchi M Fujita M Umi M Hirano T Matsubara S Ueno 《Canadian Metallurgical Quarterly》1998,157(1):52-59
This study examined the effect of thyrotrophin-releasing hormone (TRH) administration on thermoregulation in the newborn. Twin lambs were either delivered near-term by caesarean section or born vaginally at term. Colonic temperature, O2 consumption, CO2 production, breathing and heart rates, plus plasma thyroid hormone and nonesterified fatty acid (NEFA) concentrations and thermogenic activity (i.e. GDP binding) of brown adipose tissue (BAT) were measured. In caesarean section delivered lambs colonic temperature decreased rapidly after birth, a response that was greater in the group designated for TRH treatment, in which colonic temperature fell to below 36.0 degrees C at 80 min of life, prior to TRH administration. At this age colonic temperature had been restored to a mean of 38.70 degrees C in controls. TRH had no influence on the composition or thermogenic activity of BAT. The incidence of shivering was not influenced by TRH, but treated lambs maintained a higher rate of O2 consumption and ventilation compared with controls after colonic temperature had been restored to 38.56 degrees C. TRH appeared to promote fat oxidation as O2 consumption remained unchanged and CO2 production declined by a greater rate in treated lambs, resulting in a lower respiratory quotient compared to controls. Heart rate and plasma concentrations of NEFA increased following TRH administration although this did not result in values greater than controls. Normothermic lambs born vaginally had BAT with a greater thermogenic activity, higher plasma thyroid hormone and NEFA concentrations compared with caesarean section delivered lambs, but a thermogenic response was not observed to TRH despite a rise in thyroid hormone concentrations. In conclusion, TRH can improve thermoregulation, an effect that could be linked to an increase in fat oxidation. 相似文献
29.
The optimal periodic control of a single nonisothermal CSTR in which a single reaction, a parallel reaction or a consecutive reaction is taking place is studied. Both the feed rate and the heat transfer between the reactor content and the immersed coil are periodically controlled. Utility consumption and conversion of the raw material into the waste are included in the performance index together with conversion into the desired product. The results indicate a respectable improvement in the reactor performance. 相似文献
30.