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71.
72.
采用光纤技术实现拉曼光谱和扫描隧道显微镜实时联用测试 总被引:1,自引:0,他引:1
设计并制作了与扫描隧道显微镜(STM)探头和拉曼光谱仪相适配的光纤探测装置,该装置采用配有不很短焦距的自聚焦透镜以获得较大的相对孔径,并使用多束光纤以充分利用扫描隧道显微镜探针周围有限空间,提高了拉曼散射光的收集效率,获得具有较高信噪比的拉曼谱图,在该装置的基础上进一步建立拉曼-扫描隧道显微镜联用系统,初步实验表明该联用系统用于实时研究固/气和固/液界面体系是可行的,即利用扫描隧道显微镜可获得固体 相似文献
73.
Wu Shi-fa 《Frontiers of Physics in China》2006,1(3):263-274
This review has introduced a new near-field optical microscope (NOM)—atomic force microscope combined with photon scanning
tunneling microscope (AF / PSTM). During scanning, AF/PSTM could get two optical images of refractive index image and transmissivity
image, and two AFM images of topography image and phase image. A reflected near-field optical microscope (AF/RSNOM) has also
been developed on AF/PSTM platform. The NOM has been reviewed in this paper and the comparison between AF/PSTM & RSNOM and
the commercial A-SNOM & RNOM has also been discussed. The functions of AF/PSTM & RSNOM are much better than A-SNOM & RNOM. 相似文献
74.
Jiali Gao 《Journal of Chemical Sciences》1994,106(2):507-519
The origin of the solvent effects on the free energy of activation for the isomerization of N,N-dimethylformamide in water,
CHCl3 and CCl4 has been investigated through statistical mechanical simulations using the combined quantum mechanical and molecular mechanical
AM1/OPLS potential. The differential solvations between the ground state and transition state in various solvents can be attributed
to the differences in molecular dipole moments in solution, and to the solvent polarization effects. In polar solvents, DMF
is polarized more favorably in the ground state than in the rotated conformers, leading to greater solvent contributions.
The modest solvent effects in CCl4 are a reflection of its much smaller dielectric constant. 相似文献
75.
煤的清洁利用技术的现状与发展 总被引:1,自引:0,他引:1
文章针对中国一次能源以煤为主的特点,深入分析了几种主要的煤的洁净利用技术的现状及存在的主要问题和发展趋势,其中包括大容量、高参数的超(超)临界燃煤发电技术、燃煤烟气净化技术、循环流化床燃烧技术(CFBC)、整体煤气化联合循环技术(IGCC)和煤的洗选技术.在此基础上,给出了中国煤的清洁利用方式的建议:近期仍以超(超)临界燃煤发电机组+燃煤烟气净化技术和循环流化床燃烧技术为主;整体燃气化联合循环技术、富氧燃烧技术(特别是加压富氧燃烧技术)以及二氧化碳的捕集和封存技术(CCS),具有广阔应用前景,值得长期大力发展. 相似文献
76.
以氟化镁为基底材料, 采用基底、金属网栅与频率选择表面一体化设计方法设计了一种雷达波与光学波段双带通的结构. 利用模式匹配法对设计结构的传输特性进行了仿真研究, 并将设计结果与制备样件的测试结果进行了对比分析. 结果发现: 采用一体化设计的方法设计光学透明频率选择表面, 不仅能够快速得到电场基函数而且还能够准确预估其谐振尺寸, 从而在提高计算效率的同时避免了模式互作用零点的出现. 采用一体化设计方法获得了具有稳定滤波特性的光学透明频率选择表面, 为雷达/红外双模制导头罩的电磁屏蔽技术和隐身技术提供了一种有效技术方案.
关键词:
复合制导
频率选择表面
金属网栅
一体化设计 相似文献
77.
Alakes Maiti Bibek Patra G.P. Samanta 《International Journal of Mathematical Education in Science & Technology》2013,44(8):1061-1076
The present article deals with the problem of combined harvesting of a
Michaelis–Menten-type ratio-dependent predator–prey system. The
problem of determining the optimal harvest policy is solved by invoking
Pontryagin's Maximum Principle. Dynamic optimization of the harvest policy is
studied by taking the combined harvest effort as a dynamic variable. Computer
simulations are carried out to illustrate our analytical findings. Biological
and bioeconomical interpretations of the results are explained critically. 相似文献
78.
Poly(ε-caprolactone) (PCL) composites filled by multi-walled carbon nanotubes (MWCNTs) which was non-covalently modified by the combined surfactants of poly(sodium 4-styrenesulfonate) and cetyltrimethyl-ammonium bromide (PSS-CTAB) were fabricated via simple solution precipitation method. PCL/MWCNTs composites provided with the low procolation threshold (0.4?wt%) and high electrical conductivity due to good dispersion of MWCNTs. And the excellent mechanical properties and enhanced thermal stability were also obtained with the addition of modified MWCNTs. In addition, all PCL composites showed significantly enhanced crystallization with increasing the MWCNTs contents, which demonstrated that the MWCNT-induced crystallization of PCL could effectively regulate the properties of composites. In a word, introducing non-covalent functionalized MWCNTs in the polymer system was a promising way for developing excellent conductive composites. 相似文献
79.
通过研究比较不同处理工艺对页岩气压裂采出水的效果,设计出电絮凝-O_3联合处理采出水的工艺。以化学需氧量(COD)、总悬浮物(TSS)为指标,讨论电絮凝-O_3联合工艺处理页岩气压裂采出水过程中pH、电流密度、电极间距、电解时间以及O_3通气量的影响。结果表明,当pH=8. 0、电流密度为1250A/m~2、极板间距为2cm、电解时间6min、O_3通气量为40L/h时,COD去除率为98. 3%,TSS的去除率为95. 9%,经过电絮凝-O_3联合处理后的采出水的色度、浊度、oil及NH_4-N等污染指标都达到了国家排放标准。 相似文献
80.
V. M. Molochnikov N. I. Mikheev A. A. Paereliy K. R. Khairnasov 《Thermophysics and Aeromechanics》2008,15(4):573-582
Visualization data and results of combined measurements of flow quantities in flow with separation past a rib at nominally
laminar regime of channel flow are reported. In the separation region, the flow is found to be essentially three-dimensional
and unsteady, exhibiting a distinct cellular structure and flow zones with transverse motion. It is shown that the rib-induced
flow separation gives rise to low-frequency fluctuations of flow velocity and initiates the turbulence transition in the channel
flow. The critical Reynolds number at which flow instability starts developing in the channel is estimated. It is shown that
at Reynolds numbers higher than the critical Reynolds number the linear integral scale of flow velocity fluctuations in the
channel is defined by the duct size. 相似文献