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91.
3-氨基-1,2,4-三氮唑自组装膜对黄铜的缓蚀作用   总被引:7,自引:0,他引:7  
3-氨基-1,2,4-三氮唑(ATA)是一种环境友好型金属处理剂, 以其在黄铜表面制备了自组装单分子膜(SAMs), 用电化学方法研究ATA SAMs对黄铜的缓蚀作用及其吸附行为. 结果表明, ATA分子易在黄铜表面形成稳定的ATA SAMs, SAMs抑制了黄铜的阳极氧化过程, 改变了电极表面的双电层结构, 固/液界面双电层电容明显降低, 有良好的缓蚀效果. 研究结果还表明, ATA的吸附行为符合Langmuir吸附等温式, 吸附机理是典型的化学吸附.  相似文献   
92.
A novel laser-separation method for fabrication and patterning of free-standing carbon nanotube buckypapers is reported in this study. By introducing a patterned mask, buckypapers having surface patterns could be straightforwardly fabricated; and, through a shaped support, buckypapers possessing three-dimensional curved surfaces were directly demonstrated. Property measurements indicated that the laser irradiation had unapparent effects on the buckypapers’ electrical conductivity and field-emission characteristics. In addition, based on this approach, thin buckypapers, with thickness around 15 μm, could be constantly fabricated that demonstrates the superiority over the available mass-produced methods for which buckypapers with thickness smaller than 50 μm still present challenges.  相似文献   
93.
Electroactive silica mesopores have been synthesized by encapsulating different loadings of polyaniline chains into a silica network through sol-gel reactions of TEOS in the presence of polyaniline latex with D-glucose. It should be noted that the electroactive silica mesopores at higher polyaniline loading was found to reveal higher surface areas, larger pore volume, and slightly larger pore diameters as compared to that of neat non-electroactive silica mesopores.  相似文献   
94.
In the paper, we establish a reversed Dresher’s integral inequality, based on the Minkowski inequality and an inequality due to Radon. Further, we prove Dresher-type inequalities for width-integrals of convex bodies and mixed projection bodies, respectively.  相似文献   
95.
洪斌斌  陈少永  唐昌建  张新军  胡有俊 《物理学报》2012,61(11):115207-115207
揭示了电子回旋波与低杂波协同驱动等离子体并获得协同电流的机理. 从物理上阐述了双波协同驱动在相空间上和在电流剖面上所需满足的匹配关系. 通过计算机模拟研究展示了协同驱动的净增电流与波功率之间存在的非线性关系, 并对其给出了物理上的解释.本文工作将为相关实验的设计和分析提供物理上的支撑.  相似文献   
96.
This study performs a systematic analysis of the dynamic behavior of a gear-bearing system with the turbulent flow effect, nonlinear suspension, nonlinear oil-film force and nonlinear gear mesh force. The dynamic orbits of the system are observed using bifurcation diagrams plotted using the dimensionless damping coefficient, unbalance coefficient and the dimensionless rotational speed ratio as control parameters. The onset of chaotic motion is identified from the phase diagrams, power spectra, Poincaré maps, Lyapunov exponents and fractal dimension of the gear system. The numerical results reveal that the system exhibits a diverse range of periodic, sub-harmonic and chaotic behaviors. The results presented in this study provide a detailed understanding of the operating conditions under which undesirable dynamic motion takes place in gear-bearing system and therefore offer a useful source of reference for engineers in designing and controlling such systems.  相似文献   
97.
李鸣  戴长建  谢军 《物理学报》2010,59(5):3154-3161
采用两台激光器对Sm原子奇宇称激发态的光谱及其特性进行了系统研究.利用一台波长在585 nm到663 nm之间调谐的染料激光器,将Sm原子从某个4f66s27FJ(J=0—6)态激发到具有奇宇称的4f66s6p或4f55d6s2激发态.然后,采用波长固定在532 nm的强激光束,对处于上述奇宇称激发态的Sm原子进行双光子电离,以实现探测其光谱信息 关键词: 双光子电离 奇宇称态 Sm原子  相似文献   
98.
In this paper, we first introduce a new concept ofdual quermassintegral sum function of two star bodies and establish Minkowski’s type inequality for dual quermassintegral sum of mixed intersection bodies, which is a general form of the Minkowski inequality for mixed intersection bodies. Then, we give the Aleksandrov-Fenchel inequality and the Brunn-Minkowski inequality for mixed intersection bodies and some related results. Our results present, for intersection bodies, all dual inequalities for Lutwak’s mixed prosection bodies inequalities.  相似文献   
99.
We report the reduced-strain gallium-nitride (GaN) epitaxial growth on (0001) oriented sapphire by using quasiporous GaN template. A GaN film in thickness of about 1 μm was initially grown on a (0001) sapphire substrate by molecular beam epitaxy. Then it was dealt by putting into 45% NaOH solution at 100℃ for lOmin. By this process a quasi-porous GaN film was formed. An epitaxial GaN layer was grown on the porous GaN layer at 1050℃ in the hydride vapour phase epitaxy reactor. The epitaxial layer grown on the porous GaN is found to have no cracks on the surface. That is much improved from many cracks on the surface of the GaN epitaxial layer grown on the sapphire as the same as on GaN buffer directly.  相似文献   
100.
采用TRS方法研究了168Hf核的三轴超形变核态. 通过位能面计算给出了平衡形变参数, 证实了高自旋态下该核存在三轴不对称性. 通过分析各部分修正能量, 研究了其三轴超形变形成的机制: 主要原因是中子壳修正, 同时高j闯入轨道πi13/2的形变驱动效应和转动能也起到重要作用.  相似文献   
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