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91.
微力矩导弹舵机负载模拟器的理论研究   总被引:1,自引:0,他引:1  
以某型号反坦克导弹舵机为对象,对一种称之为微力矩负载模拟器进行了研究。根据该型号导弹舵机的特点,对系统关键元件的选择设计进行了分析,建立了系统的数学模型,并通过分析多余力矩的产生机理,对系统进行了多余力矩补偿和校正,最后进行了仿真分析。  相似文献   
92.
微纳通道机械谐振器在液体环境中具有超高的谐振频率、品质因子和灵敏度,常用于液体环境中的高精度检测与表征,在生物、医药、化工等领域有着广阔的应用前景.微纳通道机械谐振器的检测与表征功能高度依赖其动力学特性,而此类器件是由谐振结构、内部流体、被检测物和外部激励等多因素组成的耦合系统,涉及的动力学问题较为复杂,已成为谐振器件研究中的前沿热点和瓶颈问题.本文综述了微纳通道机械谐振器的研究进展,总结了谐振器件实现高精度检测与表征功能时的动力学设计原理,详细讨论了谐振器件的稳定性、频响特性、能量耗散、频率波动等动态特性,阐明了不同动力学问题的物理机制及其对谐振器性能的影响规律,可为深入厘清微纳通道机械谐振器的动力学设计问题,提高器件动态性能提供理论参考和技术支撑,对超高频、超高灵敏度谐振器的设计、制造及应用发展具有重要意义.  相似文献   
93.
The microenvironments of a leucine‐based organogel are probed by monitoring the fluorescence behavior of coumarin 153 (C153) and 4‐aminophthalimide (AP). The steady‐state data reveals distinctly different locations of the two molecules in the gel. Whereas AP resides close to the hydroxyl moieties of the gelator and engages in hydrogen‐bonding interactions, C153 is found in bulk‐toluene‐like regions. In contrast to C153, AP exhibits excitation‐wavelength‐dependent emission, indicating that the environments of the hydrogen‐bonded AP molecules are not all identical. A two‐component fluorescence decay of AP in gel, unlike C153, supports this model. A time‐resolved fluorescence anisotropy study of the rotational motion of the molecules also reveals the strong association of only AP with the gelator. That AP influences the critical gelation concentration implies its direct involvement in the gel‐formation process. The results highlight the importance of guest–gelator interactions in gels containing guest molecules.  相似文献   
94.
Solid–liquid–vapor interfaces dominated by the three‐phase contact line, usually performing as the active center in reactions, are important in biological and industrial processes. In this contribution, we provide direct three‐dimensional (3D) experimental evidence for the inside morphology of interfaces with either Cassie or Wenzel states at micron level using X‐ray micro‐computed tomography, which allows us to accurately “see inside” the morphological structures and quantitatively visualize their internal 3D fine structures and phases in intact samples. Furthermore, the in‐depth measurements revealed that the liquid randomly and partly located on the top of protrusions on the natural and artificial superhydrophobic surfaces in Cassie regime, resulting from thermodynamically optimal minimization of the surface energy. These new findings are useful for the optimization of classical wetting theories and models, which should promote the surface scientific and technological developments.  相似文献   
95.
To probe the intrinsic stress distribution in terms of spatial Raman shift (ω) and change in the phonon linewidth (Γ), here we analyze self‐assembled graphene oxide fibers (GOF) ‘Latin letters’ by confocal Raman spectroscopy. The self‐assembly of GOF ‘Latin letters’ has been explained through surface tension, π–π stacking, van der Waals interaction at the air–water interface and by systematic time‐dependent investigation using field emission scanning electron microscopy analysis. Intrinsic residual stress due to structural joints and bending is playing a distinct role affecting the E2g mode (G band) at and away from the physical interface of GOF segments with broadening of phonon linewidth, indicating prominent phonon softening. Linescan across an interface of the GOF ‘letters’ reveals Raman shift to lower wavenumber in all cases but more so in ‘Z’ fiber exhibiting a broader region. Furthermore, intrinsic stress homogeneity is observed for ‘G’ fiber distributed throughout its curvature with negligible shift corresponding to E2g mode vibration. This article demonstrates the significance of morphology in stress distribution across the self‐assembled and ‘smart‐integrable’ GOF ‘Latin letters’. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
96.
We report the appearance and enhancement in intensity of impurity related local vibrational modes in Bi2O3 : Ho micro‐rods along with normal modes. Pure and Ho‐doped Bi2O3 micro‐rods were synthesized by conventional co‐precipitation method at 60 °C. The structural and morphological studies were carried out using powder X‐ray diffraction technique and scanning electron microscopy, respectively. Raman spectroscopic studies reveal the existence of local phonon vibrational modes (LVM) due to the incorporation of Ho3+. Harmonic approximation method was employed to find the dopant‐related peak in the Raman spectra. Variation in full width at half maximum for LVM with increase in Ho3+ was also investigated. This increase in FWHM indicates the decrease in crystallinity of the doped samples. The phonon lifetime calculation carried out for each samples and the decrease in phonon lifetime with doping concentration make this material a potential candidate for optical and electronic applications. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
97.
The micro‐structure of hydration shell of solute in water is significant for understanding the properties of aqueous solutions. However the spectra of hydration shell are difficult to be obtained. Herein, a novel Raman ratio spectra, which is obtained through dividing the Raman spectra of aqueous solutions from the spectrum of water, was applied to deduce the spectra of hydration shell of organic (acetone‐D6) and inorganic compounds (NaNO3, NaSCN, NaClO4, Na2SO4, NaCl) in water. Those spectra of the hydration shell were employed to study the micro‐structures of the first hydration shells of anions, the number of water molecules in the first hydration shell of free anions and acetone‐D6, and the aggregation behavior of ions in the concentrated aqueous NaNO3. The number of water molecules in the hydration shell was supported by our molecular dynamic simulations. The Raman ratio spectra can be widely employed to obtain the spectra of the first hydration shell, and it is helpful to understand the micro‐structure of aqueous solutions. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
98.
Ya Jin  Takashi Manabe  Wen Tan 《Electrophoresis》2015,36(17):1991-2001
Human bronchial smooth muscle cell soluble proteins were analyzed by a combined method of nondenaturing micro 2DE, grid gel‐cutting, and quantitative LC‐MS/MS and a native protein map was prepared for each of the identified 4323 proteins [1]. A method to evaluate the degree of similarity between the protein maps was developed since we expected the proteins comprising a protein complex would be separated together under nondenaturing conditions. The following procedure was employed using Excel macros; (i) maps that have three or more squares with protein quantity data were selected (2328 maps), (ii) within each map, the quantity values of the squares were normalized setting the highest value to be 1.0, (iii) in comparing a map with another map, the smaller normalized quantity in two corresponding squares was taken and summed throughout the map to give an “overlap score,” (iv) each map was compared against all the 2328 maps and the largest overlap score, obtained when a map was compared with itself, was set to be 1.0 thus providing 2328 “overlap factors,” (v) step (iv) was repeated for all maps providing 2328 × 2328 matrix of overlap factors. From the matrix, protein pairs that showed overlap factors above 0.65 from both protein sides were selected (431 protein pairs). Each protein pair was searched in a database (UniProtKB) on complex formation and 301 protein pairs, which comprise 35 protein complexes, were found to be documented. These results demonstrated that native protein maps and their similarity search would enable simultaneous analysis of multiple protein complexes in cells.  相似文献   
99.
A monolithic fiber of molecularly imprinted polymer (MIP) was prepared by in situ polymerization within the capillary with an inner diameter of 530 µm. It was carried out in 8 min by microwave irradiation using malachite green (MG) as a template molecule, α‐methacrylic acid (MAA) as a functional monomer, acetonitrile (ACN) as a porogenic solvent, ethylene dimethacrylate (EDMA) as a crosslinker, azodiiso‐butyronitrile (AIBN) as a thermal initiator. The resulted MIP fibers were pushed out from the capillary, eluted and inserted in the capillary again, which successfully used for the solid phase microextraction (SPME) procedure. The factors affecting the extraction of MG, such as the molar ratio of template/monomer (MG/MAA), concentration of NaCl, extraction and desorption time, and extraction and desorption solvents were investigated in detail. The selectivity of the MIP fibers was compared using MG analogues crystal violet (CV) and non‐analogue Sudan II. It was also employed for the pretreatment of trace MG in the fish feed followed by high‐performance liquid chromatography (HPLC) detection. Under the optimal conditions, the linear range of MG was 10‐600 μg/L, the detection limit (LOD) was 1.23 μg/L and the recovery of spiked fish feed sample was 88.7~113.9%.  相似文献   
100.
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