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991.
Humio Ichimura 《Journal of Number Theory》2008,128(4):858-864
Let p be a prime number. We say that a number field F satisfies the condition when for any cyclic extension N/F of degree p, the ring of p-integers of N has a normal integral basis over . It is known that F=Q satisfies for any p. It is also known that when p?19, any subfield F of Q(ζp) satisfies . In this paper, we prove that when p?23, an imaginary subfield F of Q(ζp) satisfies if and only if and p=43, 67 or 163 (under GRH). For a real subfield F of Q(ζp) with F≠Q, we give a corresponding but weaker assertion to the effect that it quite rarely satisfies . 相似文献
992.
993.
Xiqian Zhang Rujun Ma Xiaojuan Liu Xuehua Jiang Ling Wang 《Biomedical chromatography : BMC》2016,30(12):1915-1921
A rapid and sensitive liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method has been developed and validated for simultaneous quantification of ginsenosides Rg1, Re and notoginsenoside R1 in human plasma. Chromatography was performed on Capcell Pak C18 MG II column using a binary gradient using mobile phase A (5 mm ammonium formate solution) and B (methanol, containing 5 mm ammonium formate) at a flow rate of 0.3 mL/min. The entire chromatographic run time was 3.2 min. Quantification was achieved using multiple reaction monitoring in positive mode using API 3000. This method was validated in terms of specificity, linearity, precision, accuracy, matrix effect and stability. The calibration curves were linear in the concentration range of 0.020–5.00 ng/mL for ginsenosides Rg1, Re and notoginsenoside R1. The lower limit of quantification (LLOQ) of this method was 0.020 ng/mL. The intra‐run and inter‐run precision values were within 12.31% for ginsenoside Rg1, 14.13% for ginsenoside Re and 11.46% for notoginsenoside R1 at their LLOQ levels. The samples were stable under all tested conditions. This method was successfully applied to study the pharmacokinetics of ginsenoside Rg1 and notoginsenoside R1 in 24 healthy volunteers following oral administration of 200 mg Sanqi Tongshu Enteric‐Pellets Capsule. 相似文献
994.
In this work, Paschen curve for argon gas was obtained during copper deposition using a DC magnetron sputtering system. Five process parameters of Paschen curve were used to obtain the electron density and deposition rate of the deposited nanostructured thin films. Plasma parameter such as electron density was correlated with the deposition rate. It is observed that a minimum deposition rate was obtained for the plasma process parameter corresponding to the Paschen minimum. This investigation helps to understand and optimize the quality of nanostructured thin films depending on the process parameters. 相似文献
995.
Experimental and analytical investigation was carried out to show the effect of surface tension on the heat transfer coefficient of gas flow inside micropipe heat exchangers during the condensation process. An empirical correlation was formulated for the coefficient of the convective heat transfer. A comprehensive comparison between the experimental results with published correlations in the literature and that obtained by the developed correlation was conducted. The results showed that the predicted heat transfer coefficient of the proposed correlation was closer to the experimental results than any other correlation, a finding related to the consideration of the surface tension. 相似文献
996.
We constrain the neutrino mass in f(R) gravity using the latest observations from the Planck, BAO and BICEP2 data. We find that the measurement on the B-modes can break the degeneracy between the massive neutrinos and the f(R) gravity. We find a non-zero value of the Compton wavelengths B0 at a 68% confidence level for the f(R) model in the presence of massive neutrinos when the BICEP2 data is used. Furthermore, the tension on the tensor-to-scalar ratios between the measured values from Plank and BICEP2 is significantly reconciled in our model. 相似文献
997.
《Current Applied Physics》2014,14(3):322-330
Au/PVC + TCNQ/p-Si structure was fabricated and real and imaginary parts of the dielectric constant (ɛ′, ɛ″), loss tangent (tanδ), and the real and imaginary parts of the electric modulus (M′, M″) and ac conductivity (σac) of this structure have been investigated in wide frequency a range of 1 kHz–5 MHz at room temperature. All of these parameters were found strong function of frequency and voltage especially in the inversion and depletion regions at low frequencies due to interfacial polarization and charges at interface states (Nss). The decrease in ɛ′ and ɛ″ with increasing frequency indicated that the interfacial dipoles have less time to orient themselves in the direction of the alternate field. While the value of M′ increase with increasing frequency and reach a maximum, M″ shows a peak and the peak position shifts to higher frequency with increasing applied voltage. The ln(σac) vs ln(ω) plot of the structure for 0.5 V has three linear regions (I, II and III) with different slopes which correspond to low, intermediate and high frequency ranges, respectively. Such behavior of ln(σac) vs ln(ω) plot indicated that there are three different conduction mechanisms in the Au/PVC + TCNQ/p-Si structure at room temperature. 相似文献
998.
该文借助于犛犔(2,犚)上李代数及其万有包络代数讨论了犛犔(2,犚)上函数的Fourier变换在无穷远处下降的阶与函数的光滑性的关系,我们得到的结论较[6]中的结论好,并由此得到犆2犮(犌)中的Plancherel定理. 相似文献
999.
Charles Garnet Cox 《代数通讯》2019,47(3):978-989
1000.