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981.
Hydrophobins are small fungal proteins, which have remarkable surface-chemical properties. They self-assemble at hydrophobic/hydrophilic interfaces and work as adhesive agents and coatings. Sixteen layer Langmuir-Blodgett films of hydrophobins HFBI and HFBII from the fungus Trichoderma reesei were prepared and studied using grazing-incidence X-ray diffraction and reflectivity techniques. Both kind of films contain hexagonally ordered crystallites on the substrate with unit cell parameters of a = b = 54 Å (HFBI) and a = b = 55 Å (HFBII). The structure is similar to the structure of monolayer Langmuir-Blodgett films. 相似文献
982.
报告了在13.5-14.6MeV中子能区,用活化法(以93Nb(n,2n)92mNb反应截面为中子注量标准)测得的50Cr(n, 2n)49Cr和52Cr(n, 2n)51Cr的反应截面. 由能量为13.5±0.3 ,14.1±0.2,14.4±0.3 和14.6±0.3MeV的中子引起的50Cr(n, 2n)49Cr反应截面值分别为3.4±0.2,6.8±0.3,21.5±1.0 和25.0±1.2mb,52Cr(n, 2n)51Cr的反应截面值分别为185±10,193±9,258±13 和332±16mb. 单能中子用T(d,n)4He反应获得,其能量用铌锆截面比法测定. 另外,为避免热中子引发的50Cr(n, 2g)51Cr对52Cr(n, 2n)51Cr反应截面的影响,在样品被辐照过程中对样品进行了包镉处理,并将实验结果与尽可能收集到的其它实验数据进行了比较. 相似文献
983.
The claim of Mohapatra and Maharana thattb(s) is a better scaling variable thant(lns)2 is put to test in the case of Λ-p scattering, after parametrizingb(s) asC
1 +C
2(lns)α. It was observed that in this case the data also prefer anα value which is close to those obtained by Mohapatra and Maharana for other scattering processes. 相似文献
984.
L Hai-Jiang YE Yun-Xiu YAN Xin-Hu CHENG He-Ping JIAO Zheng HE Ju LIU Ren-Chen 《中国物理C(英文版)》2008,32(8)
In the GDH sum rule measurement in JLab Hall-A,to obtain the cross section of electron scattering on polarized 3He and its asymmetry in different helicity states,the dilution effect from unpolarized nitrogen mixed in the polarized 3He target were calculated at different kinematic settings. 相似文献
985.
M. A. Abdel-Raouf 《Il Nuovo Cimento D》1989,11(3):433-453
Summary The inelastic scattering of positrons by 11 lithium-isoelectronic ions, (with nuclear chargesZ=4,5,… 14) is investigated for the first time within the framework of the coupled-static and frozen-core approximations. It
is assumed that the elastic and positronium channels, in each process, are open and all excitation channels of the target
are closed. The calculations of the total cross-sections are carried out by employing eight partial waves, (corresponding
to 0≤l≤7, wherel is the total angular momentum of the scattering problem considered). Also, the effect of switching on the polarization potentials
of the positroniums on the rearrangement cross-sections is investigated in details. Particular attention is devoted to the
relation between the positronium formation cross-sections and the increase in the nuclear charge of the targets.
To speed up publication, the author of this paper has agreed to not receive the proofs for correction. 相似文献
986.
非水体系中哌啶在银电极表面的表面增强喇曼散射 总被引:1,自引:0,他引:1
本文测定了哌啶在甲醇溶液中吸附在银电极表面的表面增强喇曼散射(SERS)光谱,及其随电位的变化,同时还测定了电极经不同氧化-还原循环(ORC)预处理时的SERS谱,对所得结果进行了分析比较,并进一步研究了非水体系和水体系SERS谱之间的关系.实验结果表明:哌啶在甲醇体系中比在水体系中SERS谱的增强因子要小,并且它们的SERS谱线随电位的变化也有一定的差别. 相似文献
987.
The to and fro motion of a bouncing ball on a flat surface is represented by a low-dimensional model. To describe the repeated reversals of the horizontal velocity of the ball, the elasticity of the ball has to be taken into account. We show that a simple fly-wheel model exhibits the observed hither and thither motion of elastic balls. The suggested model is capable of describing oblique impacts of spherical bodies, which can be important in many applications, including dynamical simulation of granular materials. We find that the behaviour of the bouncing fly-wheel is sensitive to the initial conditions, and the escape time plots are used to illustrate this observation. 相似文献
988.
G K Raju K Venkataramaniah M S Prasad K Narasimhamurty V A Narasimhamurty 《Pramana》1986,26(4):327-335
Differential incoherent scattering cross-section ratios of 279.2 keV photons by zirconium, tin, tantalum, lead and uranium
elements are experimentally determined by comparing the peak areas under the degraded photon energy with that of an equivalent
aluminium foil employing a high resolution 35 c.c. coaxial Ge(Li) detector. Studies have been made in single configuration
in an angular range of 20° to 115°. The results are compared with theoretical values obtained from the non-relativistichfs model of Hubbell and co-workers. The cross-section ratios decrease as the atomic number increases for a given scattering
angle. 相似文献
989.