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101.
MOHAMED SAÏDI 《Compositio Mathematica》1997,107(3):319-338
Let R be a discrete complete valuation ring, with algebraically closedresidue field. Let X be a semi-stable R-curve, with smooth generic fibre. In this paper we study tame coverings of X. 相似文献
102.
本文由Priestley渐进谱理论导出了非平稳随机过程蒙特卡罗模拟的一个谱表示方法.按照该方法,样本过程可直接由一余弦级数公式计算产生.可以证明,当级数项数足够大时,模拟的样本过程可准确地反映非平稳随机过程规定的性质;当产生的样本过程足够多时,其总体均值和总体自相关函数均趋于相应目标函数;样本过程随着级数项数趋于无穷而渐近呈正态分布.本文方法最显著的特点在于可以借助随机相位角产生具有某些预期特征的样本过程. 相似文献
103.
Mazzocchi C Grzywacz R Liddick SN Rykaczewski KP Schatz H Batchelder JC Bingham CR Gross CJ Hamilton JH Hwang JK Ilyushkin S Korgul A Królas W Li K Page RD Simpson D Winger JA 《Physical review letters》2007,98(21):212501
An alpha-decay branch of (1.4+/-0.4) x 10(-4) has been discovered in the decay of 109I, which predominantly decays via proton emission. The measured Q(alpha) value of 3918+/-21 keV allows the indirect determination of the Q value for proton emission from 105Sb of 356+/-22 keV, which is approximately of 130 keV more bound than previously reported. This result is relevant for the astrophysical rapid proton-capture process, which would terminate in the 105Sn(p,gamma)106Sb(p,gamma)107Te(alpha decay)103Sn cycle at the densities expected in explosive hydrogen burning scenarios, unless unusually strong pairing effects result in a 103Sn(p,gamma)104Sb(p,gamma)105Te(alpha decay)101Sn) cycle. 相似文献
104.
Tuning the energy gap of conjugated polymer zwitterions for efficient interlayers and solar cells
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Zachariah A. Page Feng Liu Thomas P. Russell Todd Emrick 《Journal of polymer science. Part A, Polymer chemistry》2015,53(2):327-336
Narrow band gap conjugated polymer zwitterions (CPZs) were synthesized by Suzuki polymerization and characterized to understand their electronic properties and utility as cathode modification layers in solar cells. The polymers were prepared from diketopyrrolopyrrole (DPP) and iso-indigo monomers containing sulfobetaine (SB) pendant groups, benefiting from an ion-rich aqueous phase in the polymerizations. UV–vis absorption spectroscopy revealed the optical energy gap value for the CPZs, ranging from 1.7 to 1.2 eV. Ultraviolet photoelectron spectroscopy of the CPZs as thin layers on Ag metal showed that the pendent zwitterions impart an interfacial dipole (Δ) to the metal and a work function reduction of ∼0.9 eV. OPVs fabricated using a conventional bulk heterojunction (BHJ) device architecture of ITO/PEDOT:PSS/(PTB7:PC71BM)/CPZ/Ag led to dramatic improvements in power conversion efficiency (PCE) values relative to devices having bare Ag cathodes (PCE < 2% for bare Ag vs. 6.7–7.7% for CPZ/Ag). The benzothiadiazole (BT)/DPP polymer denoted as PT2BTDPPSB gave an optimal PCE of 7.7% in a conventional BHJ OPV device architecture fabricated on a Ag cathode. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 327–336 相似文献
105.
采用UV-Vis光谱、红外吸收光谱、CHN元素分析及激光解析飞行时间质谱对α-四(对磺酸钠苯氧基)酞菁锌(钴,镍)[α-PhSPcZn(Co,Ni)]进行表征.在光诱导条件下,采用四甲基偶氮唑蓝比色法(MTT法),考察了光敏剂的中心原子、浓度和光照时间等条件下对癌细胞的抑制作用.结果显示,光照15min、浓度为0~100mg·L-1范围内时,α-PhSPcZn的抑瘤率高于α-PhSPcCo和α-PhSPcNi.抑瘤率均随光照时间和配合物浓度的增加而升高,α-PhSPcZn的抑制率可达54%,其IC50值为75mg·L-1. 相似文献
106.
107.
Microprojectile methods of genetic engineering sometimes employ a macroprojectile which launches the microprojectiles when it hits a stopping plate. A study has been made of the relationship between the velocities of the macroprojectile and the microprojectile it launches. Macroprojectile velocities were measured using a beam blanking method and the microprojectile velocities were measured with a laser Doppler anemometer. Particles of tungsten, titanium dioxide and silicon carbide were investigated as microprojectiles. The microprojectile velocity was found to depend not only on the macroprojectile velocity but also on the microprojectile size and material, the bond strength with the macroprojectile and the gas flow that develops ahead of the macroprojectile. On average the microprojectile launch velocity was similar to the macroprojectile velocity. However, some tungsten particles had velocities twice this value. Experimental evidence suggests that these higher velocities were caused by early break-way of particles from the macroprojectile followed by further acceleration by aerodynamic drag arising from the gas flow ahead of the macroprojectile.We are especially grateful for the advice of Dr. M. Gharib on the use of the HSI color system. John Lyons provided expert help in the laboratory and materials for and advice on photography. We thank the staff of the SIO Hydraulics Laboratory for making the wind-wave channel available for our use, and the staff of UCSD library for enabling us to use the Barneyscanner photometer-digitizer. We thank an anonymous reviewer who pointed out a numerical error and improved the clarity of the text. 相似文献
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It has been reported that the introduction of a dielectric barrier between adjacent digits of an interdigitated electrode array can improve the sensitivity of the array as an electrochemical impedance biosensor. Here we present an in‐depth analysis of the impedance in planar interdigitated electrodes and 3‐D interdigitated electrodes (with dielectric barriers). The analysis indicates that the planar geometry not only provides lower impedance but also a higher change impedance as a result of molecular immobilization on the electrode array surface. 相似文献