Mechanical assembly has its own dynamic quality directly affecting the dynamic quality of whole product and should be considered in quality inspection and estimation of mechanical assembly. Based on functional relatio...Mechanical assembly has its own dynamic quality directly affecting the dynamic quality of whole product and should be considered in quality inspection and estimation of mechanical assembly. Based on functional relations between dynamic characteristics involved in mechanical assembly, the effects of assembling process on dynamic characteristics of substructural components of an assembly system are investigated by substructuring analysis. Assembly-coupling dynamic stiffness is clarified as the dominant factor of the effects and can be used as a quantitative measure of assembly dynamic quality. Two computational schemes using frequency response functions（FRFs） to determine the stiffness are provided and discussed by inverse substructuring analysis, including their applicable conditions and implementation procedure in application. Eigenvalue analysis on matrix-ratios of FRFs before and after assembling is employed and well validates the analytical outcomes and the schemes via both a lumped-parameter model and its analogic experimental counterpart. Applying the two schemes to inspect the dynamic quality provides the message of dynamic performance of the assembly system, and therefore improves conventional quality inspection and estimation of mechanical assembly in completeness.展开更多
To achieve a stable, sensitive, and high-efficiency biological probe, a novel NaYF4：Yb,Er nanocrystals/TiO2 inverse opal composite film was designed by self-assembly and solvent evaporation methods. 32-fold enhanced ...To achieve a stable, sensitive, and high-efficiency biological probe, a novel NaYF4：Yb,Er nanocrystals/TiO2 inverse opal composite film was designed by self-assembly and solvent evaporation methods. 32-fold enhanced upconversion（UC） emission was investigated under 980 nm excitation. According to size-dependency, excitation power density-dependency as well as photonic stop band（PSB）-dependency upconversion spectra, the enhancement mechanism of the composite film was put down to the stochastical diffraction of IOPCs multi-layered structure to the excitation laser. On the basis of the enhancement effect of the composite film, energy transfer between upconversion nanoparticles（UCNPs） and quantum dots（QDs）, and the sensitive sensing of CdTe QDs on mercury, the UC composite film was used for sensing of Hg^2＋ in serum. The solid sensor as a mercury detector owns lots of superiorities such as feasible operation, good linear relationship（R=0.997）, low limit of detection（70.5 nmol/L） and thus may have broad prospects in the biosensing field.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51475211)
文摘Mechanical assembly has its own dynamic quality directly affecting the dynamic quality of whole product and should be considered in quality inspection and estimation of mechanical assembly. Based on functional relations between dynamic characteristics involved in mechanical assembly, the effects of assembling process on dynamic characteristics of substructural components of an assembly system are investigated by substructuring analysis. Assembly-coupling dynamic stiffness is clarified as the dominant factor of the effects and can be used as a quantitative measure of assembly dynamic quality. Two computational schemes using frequency response functions（FRFs） to determine the stiffness are provided and discussed by inverse substructuring analysis, including their applicable conditions and implementation procedure in application. Eigenvalue analysis on matrix-ratios of FRFs before and after assembling is employed and well validates the analytical outcomes and the schemes via both a lumped-parameter model and its analogic experimental counterpart. Applying the two schemes to inspect the dynamic quality provides the message of dynamic performance of the assembly system, and therefore improves conventional quality inspection and estimation of mechanical assembly in completeness.
基金Project supported by National Natural Science Foundation of China(11374044)Fundamental Research Funds for the Central Universities(3132016333,3132017058)+1 种基金Doctor Start-up Funds of Liaoning Province(201601067)China Postdoctoral Science Foundation(2016M591420)
文摘To achieve a stable, sensitive, and high-efficiency biological probe, a novel NaYF4：Yb,Er nanocrystals/TiO2 inverse opal composite film was designed by self-assembly and solvent evaporation methods. 32-fold enhanced upconversion（UC） emission was investigated under 980 nm excitation. According to size-dependency, excitation power density-dependency as well as photonic stop band（PSB）-dependency upconversion spectra, the enhancement mechanism of the composite film was put down to the stochastical diffraction of IOPCs multi-layered structure to the excitation laser. On the basis of the enhancement effect of the composite film, energy transfer between upconversion nanoparticles（UCNPs） and quantum dots（QDs）, and the sensitive sensing of CdTe QDs on mercury, the UC composite film was used for sensing of Hg^2＋ in serum. The solid sensor as a mercury detector owns lots of superiorities such as feasible operation, good linear relationship（R=0.997）, low limit of detection（70.5 nmol/L） and thus may have broad prospects in the biosensing field.
