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1.
This paper is devoted to the quasilinear equation ■where p 2,Ω is a(bounded or unbounded) domain of R~N,w_1,w_2 are nonnegative continuous functions and f is an increasing function. We establish a Liouville type theorem for nontrivial stable solutions of the equation under some mild assumptions on Ω,w_1, w_2 and f, which extends and unifies several results on this topic. 相似文献
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We report on an accurate intensity calibration method for low wavenumber Raman spectroscopy. It uses the rotational Raman spectrum of N2. The intensity distributions in the rotational Raman spectra of diatomic molecules are theoretically well established. They can be used as primary intensity standards for intensity calibration. The intensity ratios of the Stokes and anti‐Stokes transitions originating from the same rotational levels are not affected by thermal population. Taking the effect of rotation–vibration interactions appropriately into account, we are able to calculate these intensity ratios theoretically. The comparison between the observed and calculated ratios of the N2 pure rotational spectrum provides an accurate relative sensitivity curve (error ~5 × 10−4) in the wavenumber region of −150 to 150 cm−1. We determine the temperature of water solely from the low wavenumber Raman spectra, using a thus calibrated spectrometer. The Raman temperature shows an excellent agreement with the thermocouple temperature, with only 0.5 K difference. The present calibration technique will be highly useful in many applications of low wavenumber quantitative Raman spectroscopy. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Chikao Onogi Michiyo Motoyama Hiro‐o Hamaguchi 《Journal of Raman spectroscopy : JRS》2008,39(5):555-556
High concentration trans form unsaturated lipids have been found in a HeLa cell by Raman microspectroscopy. Two CC stretch bands are observed simultaneously at 1669 cm−1 (trans form) and at 1656 cm−1 (cis form) in a Raman spectrum obtained from a small area (1 µm in diameter) in a HeLa cell. The intensity ratio 1669/1656 indicates that the concentration of the trans form is as high as that of the cis. It is demonstrated that Raman microspectroscopy provides a powerful and unique means for in situ and noninvasive structural characterization of unsaturated lipids in a living cell. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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The reaction between glass-like carbon (GC) and chlorine trifluoride (ClF3) gas was investigated with weight measurements, surface analysis, and gas desorption measurements, where the ClF3 gas is used for the in situ cleaning of tubes in silicon-related fabrication equipment. From Auger electron spectroscopy and X-ray photoelectron spectroscopy measurements, a carbon mono-fluoride, –(CF)n–, film near the surface of GC is considered to be grown onto the GC surface above 400 °C by the chemical reaction with ClF3, and this thickness of the fluoride film depends on the temperature. The grown fluoride film desorbs by annealing in a vacuum up to 600 °C. Although GC is apparently etched by ClF3 over 600 °C, the etch rate of GC is much lower than that of SiC and quartz. 相似文献
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Yong-Woo Lee Jong-Kwang Lee Young-Kun Min Hiro-o Hamaguchi Jinwook Chung 《Analytical sciences》2008,24(4):547-550
The cell-immobilization technique is used for the physical and chemical fixation of cells onto a solid support in order to increase their stability and capacity of substrate uptake. However, there is no apparatus to observe the microbial community's structure inside cell immobilizing polymeric carrier. In order to satisfy the demand of monitoring for the microbial distribution inside the carrier, we developed an automatic phase contrast microscopic monitoring system capable of determining the microbial density and distribution inside a cell-entrapped carrier automatically. 相似文献
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以三苯胺、咔唑、4,4′-二羧基联吡啶为原料,设计并合成了两个联吡啶铱(III)配合物Ir1和Ir2,其结构经1H NMR, 13C NMR和HR-MS(MALDI-TOF)表征。并利用紫外可见光谱(UV-Vis)、荧光发射光谱(Photoluminescence)和循环伏安法研究了化合物的光学和电学性质。结果表明:Ir1和Ir2的紫外可见光吸收波长分别位于456 nm 和448 nm,相应的发射波长分别为645 nm和678 nm,说明其均能利用可见光; Ir1和Ir2的HOMO电位为-5.125~-5.510 eV, LOMO电位为-2.880~-0.310 eV,满足作为光敏剂的基本条件。研究了化合物在可见光照射下光催化水分解产生氢气的效果。结果表明:Ir1和Ir2的氢气值TONs(turnover numbers)达到2 827和1 908。 相似文献
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在渗杂度很低时,由于少数杂质电离后引起场的起伏,电子在杂质上主要处于局域状态,电声子作用使电子能够在不同杂质上跳跃,但由于电子坐标算符与电声子作用交换,在电场中电子的运动实际上是一种击穿效应,而由声子束补偿能量。针对低补偿情况,略去复杂能带结构,我们由刘维方程出发,把密度矩阵对电场,然后对电声子作用展开,得到电流表达式及密度矩阵对角元所满足的玻茲曼型方程.只取到重迭积分二次项,我们得到了Miller等的网络方程,可以简单地求出平均阻抗,在低温极限下,得到σ~e(-βε(Be-1.54(rd/a)3/2))NA1/8,βε3=βe2/(εrd) -1.93(βEA)3/4。借助网络模型,我们分析了密度矩阵各部分的贡献,特别是与通常输运过程的差别。最后利用Anderson的结果,若K<10-2,在对电导起主要作用的链上,在Ge,Si中浓度要在1014及1016cm-3以下才能形成局域态,我们认为,考虑了电子间库仑作用后,载流子非局域并不与目前实验矛盾。
关键词: 相似文献
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