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11.
通过光谱响应特性实验和记录/读出图像实验,研究了基因变异型细菌视紫红质(BRD96N)分子膜对单色光的光调制特性.发现BRD96N分子膜在550nm—600nm范围内对调制光有吸收增强的现象,且对此范围内不同波长的单色光其调制程度有差异.利用曲线拟和方法发现550nm—600nm吸收增强的变化过程分为快过程和慢过程,其对应的时间常数分别为30s和5min.利用强度调制器的吸收强度与图像灰度之间的关系,分析了560nm—600nm范围内出现图像反转的实验现象.
关键词:
细菌视紫红质D96N分子膜
光谱响应
吸收增强现象
图像反转现象 相似文献
12.
J.O. Andersen 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,28(4):389-396
We consider an interacting homogeneous Bose gas at zero temperature in two spatial dimensions. The properties of the system
can be calculated as an expansion in powers of g, where g is the coupling constant. We calculate the ground state pressure and the ground state energy density to second order in the
quantum loop expansion. The renormalization group is used to sum up leading and subleading logarithms from all orders in perturbation
theory. In the dilute limit, the renormalization group improved pressure and energy density are expansions in powers of the
T
2B and T
2Bln(T
2B), respectively, where T
2B is the two-body T-matrix.
Received 19 April 2002 Published online 13 August 2002 相似文献
13.
D.A. Garanin E.M. Chudnovsky 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,28(1):3-7
We compute the width and shape of the EPR and tunneling resonances due to dislocations in Mn12 acetate crystals. Uncorrelated dislocations produce the Gaussian shape of resonances while dislocations bound in pairs produce
the Lorentzian shape. We stress that the uniaxial spin Hamiltonian together with crystal defects can explain the totality
of experimental data on Mn12.
Received 2 August 2001 / Received in final form 15 March 2002 Published online 17 September 2002 相似文献
14.
Kj?rand Iversen Per Nilsson 《International Journal of Computers for Mathematical Learning》2007,12(2):113-133
This paper focuses on the different ways in which students in lower secondary school (14–16 year olds) experience compound
random events, presented to them in the form of combined junctions. A carefully designed ICT environment was developed enabling
the students to interact with different representations of such structures. Data for the analysis was gathered from two interview
sessions. The analysis of the interaction is based on constructivist principles on learning; i.e. we adopted a student-oriented
perspective, taking into consideration the different ways students try to make sense of chance encounters.
Our results show how some students give priority to geometrical and physical concerns, and we discuss how seeking causal explanations
of random phenomena may have encouraged this. With respect to numerically oriented models a division strategy appears to stand
out as the preferred one. 相似文献
15.
Solomon Fekade Mulugeta Bekele 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,26(3):369-374
We analyze the relaxation behavior of a bistable system when the background temperature profile is inhomogeneous due to the
presence of a localized hot region (blowtorch) on one side of the potential barrier. Since the diffusion equation for inhomogeneous
medium is model-dependent, we consider two physical models to study the kinetics of such system. Using a conventional stochastic
method, we obtain the escape and equilibration rates of the system for the two physical models. For both models, we find that
the hot region enhances the escape rate from the well where it is placed while it retards the escape rate from the other well. However, the value of the escape rate from the well where the hot region is placed differs
for the two models while that of the escape rate from the other well is identical for both. This work, for the first time,
gives a detailed report of the similarities and differences of the escape rates and, hence, exposes the common and distinct
features of the two known physical models in determining the way the bistable system relaxes.
Received 25 September 2001 相似文献
16.
A theoretical study of the electron dynamics in image potential states on Cu(1 0 0) surfaces with different types of adsorbates is presented. Scattering of the image state electron by an adsorbate induces inter-band and intra-band transitions leading respectively to the population decay and to the dephasing of the image state. We compare results obtained with low coverage (typically 1 adsorbate atom per 1000 surface atoms) Cs, Ar, and a model electronegative adsorbates. As follows from our results, Cs adsorbates lead to both appreciable dephasing and decay, while electronegative adsorbates mostly affect the dephasing rate. The effect of low coverage Ar adsorbates is small, consistent with their neutrality. 相似文献
17.
R. Lü H. Pan J.-L. Zhu B.-L. Gu 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,26(4):479-491
The tunneling of a giant spin at excited levels is studied theoretically in mesoscopic magnets with a magnetic field at an
arbitrary angle in the easy plane. Different structures of the tunneling barriers can be generated by the magnetocrystalline
anisotropy, the magnitude and the orientation of the field. By calculating the nonvacuum instanton solution explicitly, we
obtain the tunnel splittings and the tunneling rates for different angle ranges of the external magnetic field ( θ
H = π/2 and π/2 < θ
H < π). The temperature dependences of the decay rates are clearly shown for each case. It is found that the tunneling rate
and the crossover temperature depend on the orientation of the external magnetic field. This feature can be tested with the
use of existing experimental techniques.
Received 12 March 2001 and Received in final form 18 October 2001 相似文献
18.
Analysis of Spectral Reflectance Using Normalization Method from Endoscopic Spectroscopy System 总被引:2,自引:0,他引:2
Masao Sambongi Makoto Igarashi Takashi Obi Masahiro Yamaguchi Nagaaki Ohyama Masahiko Kobayashi Yasushi Sano Shigeaki Yoshida Kazuhiro Gono 《Optical Review》2002,9(6):238-243
Objective assessment of gastrointestinal mucosal color is extremely important in the endoscopic diagnosis of digestive tract disease. In this paper, we propose a method to clarify the spectral characteristics of gastric and colon cancer. A large number of spectral reflectance data of mucous membrane are measured by the endoscopic spectroscopy system (ESS) in the National Cancer Center Hospital East, Kashiwa, Japan and the Department of Internal Medicine, Self-Defense Force Center Hospital, Tokyo, Japan. We assume that early cancer appears primarily in the spectral data of short wavelength, because it is usually present in a superficial cell where short wavelength light is scattered more strongly than long wavelength light. To identify the features in the short wavelength components, the spectral reflectance was divided by the reflectance of a long wavelength. We investigated the possibility of distinguishing early cancer from normal spectral data through statistical analysis, employing the projection axis as the mean difference between them. Early cancer and normal spectral data were projected on the projection axis, and the Student’s T-test was applied to evaluate the mean of the distribution between these data. 相似文献
19.
Noriko SUTO Makoto HARADA Jun IZUTSU Toshiyasu NAGAO 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2006,82(5):175-180
In order to accurately estimate the geomagnetic transfer functions in the area of the volcano Mt. Iwate (IWT), we applied the interstation transfer function (ISTF) method to the three-component geomagnetic field data observed at Mt. Iwate station (IWT), using the Kakioka Magnetic Observatory, JMA (KAK) as remote reference station. Instead of the conventional Fourier transform, in which temporary transient noises badly degrade the accuracy of long term properties, continuous wavelet transform has been used. The accuracy of the results was as high as that of robust estimations of transfer functions obtained by the Fourier transform method. This would provide us with possibilities for routinely monitoring the transfer functions, without sophisticated statistical procedures, to detect changes in the underground electrical conductivity structure. 相似文献
20.
Summary The normal incidence reflectivity spectrum of excitons in GaAs/Ga1−x
Al
x
As multiple quantum wells is calculated within the local response approximation. It is shown that the reflectivity lineshape
strongly depends on the sample geometry. Using realistic parameters of a multiple quantum well structure, we obtain an excellent
fit of the experimental reflectivity curve, thus giving exciton energies, oscillator strengths and exciton broadening parameters.
Riassunto Lo spettro di riflettività ad incidenza normale degli eccitoni nei pozzi quantistici multipli di GaAs/Ga1−x Al x As è calcolato nell’ambito dell’approssimazione locale. Si mostra con la forma della linea di riflettività dipende in gran misura dalla forma geometrica del campione. Usando parametri realistici di una struttura a pozzi quantistici multipli, si ottiene un’ottima approssimazione della curva di riflettività sperimentale, che fornisce così energie eccitoniche, forze dell’oscillatore e parameri di ampliamento eccitonico.
Резюме В рамках приближения линейного отклика вычисляется спекрт отражательной способности экситонов при нормальном падении для множественных квантовых ям в GaAs/Ga1−x Al x As. Показывается, что форма линии отражательной способности сильно зависит от геометрии образца. Используя реалистические параметры структуры множественных квантовых ям, мы получаем хорошее соответствие с экспериментальной кривой для отражательной способности. Получаются энергии экситонов, силы осцилляторов и парам⪟тры экситонного уширения.相似文献