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                                         Microcantilever and Microbridge Systems for Mass Detection

                              314   Chapter Six







                                        1.1
                                                                         1
                                ω b,0 / ω b  1
                                          0 0
                                                                       c t

                                                  c lp          0.01
                                                               1 1
                              Figure 6.17 Bending resonant frequency ratio in terms of patch length and thickness
                              nondimensional parameters.








                                      1.2                              5
                              ω b,0 / ω b
                                      1.1
                                       0. 1
                                       0.1
                                                                     c ρ
                                                c E           0.5
                                                             1 1
                              Figure 6.18  Bending resonant frequency ratio in terms of elasticity modulus and density
                              nondimensional parameters.

                                  Figure 6.19 plots the resonant frequency ratio as a function of the patch
                                position nondimensional parameter  c l1 . It has  been plotted  for  c lp  = 0.2,
                                c t  = 0, c E  = 0.2, and c ȡ  = 0.5. While the original resonant frequency is generally
                                higher than the altered one, for cases where the patch is situated toward the
                                fixed root of the microcantilever, the relationship between the two resonant
                                frequencies reverses, as a relatively small effective mass will result from a
                                real small patch mass, which will increase the resonant frequency of the
                                microcantilever.














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