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911.
Based on the principle of maximum entropy, the q-exponential distribution can be derived from several different nonextensive entropies including the incomplete entropy. It is widely used in nonextensive statistical mechanics. In the present paper, it is shown that the incomplete expectation value and incomplete entropy are stable under small deformation of the probability distribution function of the system. 相似文献
912.
Jing Tang Fung Suong Ou Huei Pei Kuo Min Hu William F. Stickle Zhiyong Li R. Stanley Williams 《Applied Physics A: Materials Science & Processing》2009,96(4):793-797
We created novel surface-enhanced Raman spectroscopy (SERS) substrates by metalization (Ag) of Si nanograss prepared by a
Bosch process which involves deep reactive ion etching of single crystalline silicon. No template or lithography was needed
for making the Si nanograss, thus providing a simple and inexpensive method to achieve highly sensitive large-area SERS substrates.
The dependence of the SERS effect on the thickness of the metal deposition and on the surface morphology and topology of the
substrate prior to metal deposition was studied in order to optimize the SERS signals. We observed that the Ag-coated Si nanograss
can achieve uniform SERS enhancement over large area (∼1 cm ×1 cm) with an average EF (enhancement factor) of 4.2×108 for 4-mercaptophenol probe molecules.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users. 相似文献
913.
Suchun Feng Ou Xu Shaohua Lu Xiangqiao Mao Tigang Ning Shuisheng Jian 《Optics & Laser Technology》2009,41(3):264-267
A switchable erbium-doped fiber-ring laser providing dual-wavelength outputs with orthogonal polarizations when operating at room temperature is proposed. One polarization-maintaining fiber Bragg grating (PMFBG) in a Sagnac loop interferometer is used as the wavelength-selective filter. Due to the enhancement of the polarization hole burning (PHB) by the PMFBG, the laser can be designed to operate in stable dual-wavelength or wavelength-switching modes with a wavelength spacing of 0.336 nm at room temperature by adjusting a polarization controller (PC). The optical signal-to-noise ratio (OSNR) is over 42 dB. The amplitude variation over 90 min is less than 0.6 dB for both wavelengths. 相似文献
914.
Junfei Ou Jinqing Wang Sheng Liu Jinfang Zhou Shengrong Yang 《Applied Surface Science》2009,256(3):894-899
A polydopamine coating (coded as PDAc) was prepared successfully on a Si substrate through a two-step process. Briefly, to improve the adhesion of PDAc on the Si substrate, a self-assembled monolayer of 3-aminopropyl triethoxysilane (coded as APTS-SAM) was firstly generated on the bare Si wafer. Thereafter, the PDAc with different thickness was fabricated through the chemical adsorption and autopolymerization of the dopamine hydrochloride on the APTS-SAM coated Si substrate. The formation of PDAc on the APTS-SAM modified Si substrate was proved by the characterizations of contact angle measurement, attenuated total reflectance Fourier transform infrared (ATR-FTIR) analysis, and X-ray photoelectron spectroscope (XPS), etc. The ellipsometric thickness measurement and atomic force microscopy (AFM) image analysis showed that the PDAc became thicker and rougher with the deposition time prolongation. Microtribological study showed that the thickness and roughness of the PDAc played a significant role in the tribological properties. In comparison with the bare Si substrate, the PDAc with thinner thickness possessed lower friction and was anticipated to be used as protecting coating in the field of boundary lubrication. The electrochemical corrosion behaviors of the prepared PDAc were investigated using the electrochemical station and a low corrosion current density was revealed, implying that the PDAc had good anti-corrosion capability and might find potential applications in the field of corrosion resistance. 相似文献
915.
实验研究了偏振与非偏振激光对亚心形扁藻的促长作用、叶绿素含量以及色素粗提物吸收光谱等生物学效应的影响.采用488 nm,70 mW输出功率的氩激光,辐照哑心形扁藻,隔天取样进行细胞计数,培养至第6天提取叶绿素,测量叶绿素含量并扫描叶绿素的吸收光谱.实验结果表明,偏振激光与非偏振激光辐照对藻细胞密度、生长速率的促长作用区别不显著;偏振性与否对叶绿素含量的累积没有明显的区别;激光偏振性对色素粗提物的吸收光谱没有影响.激光偏振性与否均可对亚心形扁藻的生物效应产生有效的作用,激光偏振性与激光生物效应关系的研究有待于进一步深入. 相似文献
916.
By using the Euler-MacLaurin formula,this paper studies the thermodynamic properties of an ideal Fermi gas confined in a D-dimensional rectangular container.The general expressions of the thermodynamic quantities with the finite-size corrections are given explicitly and the effects of the size and shape of the container on the properties of the system are discussed.It is shown that the corrections of the thermodynamic quantities due to the finite-size effects are significant to be considered for the case of strong degeneracy but negligible for the case of weak degeneracy or non-degeneracy.It is important to find that some familiar conclusions under the thermodynamic limit are no longer valid for the finite-size systems and there are some novel characteristics resulting from the finite-size effects,such as the nonextensivity of the system,the anisotropy of the pressure,and so on. 相似文献
917.
In this paper, we introduce three probability distribution functions into the dynamic equation and propose a macro traffic flow model to investigate the impacts of the probability distribution functions on the evolutions of traffic flow under three typical states (i.e., uniform flow, shock, rarefaction wave, and small perturbation). The numerical results indicate that the probability distribution functions do not change the density and speed distributions of uniform flow, produce a two-layer shock but have no prominent effects on rarefaction wave, and have little effect on small perturbation. 相似文献
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