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191.
Straightness Measurement Using Laser Diode and CCD Camera 总被引:4,自引:0,他引:4
HAO Qun ZHAO Yang LI Dacheng CAO Mang 《Chinese Journal of Lasers》1999,8(3):215-220
1IntroductionInmanufactureandasembleofmodernmachinesandinstruments,anindispensablerequirementisthecontrolofformandpositionero... 相似文献
192.
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194.
G. Teters 《Mechanics of Composite Materials》2005,41(5):461-466
Multicriteria optimization of the structure and geometry of a laminated anisotropic composite plate subjected to the thermal
and biaxial action is considered. From known properties of the monolayer and the given values of variable structural parameters,
the thermoelastic properties of the layered composite are determined. The criteria to be optimized—the transverse critical
load and the longitudinal thermal stresses—depend on two variable design parameters of composite properties and temperature.
In the space of the optimization criteria, the domain of allowable solutions and the Pareto-optimal subdomain are found.
__________
Translated from Mekhanika Kompozitnykh Materialov, Vol. 41, No. 5, pp. 683–690, September–October, 2005. 相似文献
195.
Compromise optimization of a rectangular composite plate subjected to biaxial thermal loading and buckling under the action of shear 总被引:1,自引:1,他引:0
G. Teters 《Mechanics of Composite Materials》2008,44(4):325-330
The compromise optimization of the structure and geometry of a laminated anisotropic composite plate subjected to biaxial
thermal shear loading is considered. From the known properties of the monolayer and given values of a variable structural
parameter, the thermoelastic properties of the layered composite are determined. The optimization criteria — the critical
shear load and the longitudinal and transverse thermal stresses — depend on two variable design parameters of composite properties
and temperature. In the space of optimization criteria, the domain of allowable solutions and the Pareto-optimal subregion
are found.
__________
Translated from Mekhanika Kompozitnykh Materialov, Vol. 44, No. 4, pp. 471–478, July–August, 2008. 相似文献
196.
197.
Analysis of laser micro drilled holes through aluminium for micro-manufacturing applications 总被引:3,自引:0,他引:3
Conventional laser machining of aluminium with long wavelength lasers has its inherent problems due to the high reflectivity of aluminium to laser radiation (Handbook of Optics, vol 1, 2nd ed. New York: McGraw-Hill; 1995). Laser processing at shorter wavelengths reduces the reflectivity of the workpiece to the incident laser radiation and can also reduce the dimensions of the obtainable machining geometries. This paper reviews the limiting factors in the micro machining of aluminium using a diode pumped solid state (DPSS) Nd:YAG laser operated at 1064, 532, and 355 nm. The geometries of the laser-machined samples were investigated using interferometric, and optical methods to assess how the processing fluence and wavelength will affect the obtainable precision for successful integration of the laser in a micromachining CAD/CAM system. 相似文献
198.
推导出了停流法流动注射络合滴定的理论公式,计算了简单易实现的流路图,详细观察分析了流动注射络合滴定中的样品带与试剂流混合后在流通池中的吸光度变化。从理论上分析并预测了停流流动注射络合滴定的性质。 相似文献
199.
Quantum chemical methods are becoming ever more prevalent for assessing surface interactions of different molecules using cluster models and semi-empirical, ab initio Hartree–Fock and density functional theory (DFT) studies considering the standard potential energy surfaces. Examination of the efficacy of some pyridine derivatives to counter aluminium corrosion in hydrochloric acid using ab initio and semi-empirical quantum chemical deductions and its comparison with the available experimental data forms the basis of this research. It is believed that the inhibition efficiency has lucid correlation with the total energy of inhibitor molecules and highest occupied molecular orbital energy levels calculated by DFT study methods and thus the adsorption energy for the pyridine on Al1, Al5, Al14, Al18 and Al26 clusters are determined to assess the convergence of the results with respect to size of the cluster. Subsequently, Al26 is used for the inhibitor/aluminium cluster interface investigations. Results highlight the reaction between pyridine molecules and appropriately active sites such as corners and steps or kinks and screw dislocations towards which pyridine molecules are attracted as is evident from a three times rise in adsorption energy from (−35) to (−107) kJ mol−1. Therefore, inhibition mechanism is primarily associated with local properties. Interactions take place between the surface defect and the nitrogen group of the pyridine molecule however, the possibility of ion pair formation between protonated pyridine and chloride ion and its influence on the general adsorption of pyridine on aluminium is also examined. The interaction energies of pyridine and aluminium cluster with the natural bond orbital are also reported. 相似文献
200.