A novel into-plane rotating rnicromirror actuated by a hybrid electrostatic driving structure is presented. The hybrid driving structure is made up of a planar plate drive and a vertical comb drive. The device is fabr...A novel into-plane rotating rnicromirror actuated by a hybrid electrostatic driving structure is presented. The hybrid driving structure is made up of a planar plate drive and a vertical comb drive. The device is fabricated in SOI substrate by using a bulk-and-surface mixed silicon micromachining process. As demonstrated by experiment, the novel driving structure can actuate the mirror to achieve large-range continuous rotation as well as spontaneous 90°rotation induced by the pull-in effect. The continuous rotating range of the micromirror is increased to about 46° at an increased yielding voltage. The measured yielding voltages of the mirrors with torsional springs of 1 and 0.5μm in thickness are 390 - 410V and 140 - 160V, respectively. The optical insertion loss has also been measured to be --1.98dB when the mirror serves as an optical switch.展开更多
Interaction of a drug molecule with human serum albumin （HSA） is usually studied by fluorescence responses of the ligand or/and the single tryptophan residue （Trp-214） of the protein, but qualitative spectral info...Interaction of a drug molecule with human serum albumin （HSA） is usually studied by fluorescence responses of the ligand or/and the single tryptophan residue （Trp-214） of the protein, but qualitative spectral information may lead to multiple conclusions. In this work, we report a study on the interaction of hematoporphyrin monomethyl ether （HMME） with human serum albumin （HSA）, using the environment-sensitive spectra of HMME and reaction-induced fluorescence response of Trp-214. Particularly, the single kinetic parameter, the linear slope, was derived from the concentration-dependent absorbance or fluorescence of HMME in a certain solvent. A quantitative change in the slope at [HMME]/[HSA] = 1 ： 1 clearly demonstrated a specific binding of HMME to site I. The microenvironment in site I may be comparable to that in DMSO solvent, because of the similarity of the slope. Linear correlation of the fluorescence to the absorbance of HMME in site I indicates that the energy transfer is not responsible for Trp-214 fluorescence quenching but an electron transfer may be possible. In addition, much higher rate observed for the binding of HMME or 2-taurine-substituted HB （THB） with HSA than that of hypocrellin B was due to the electrostatic attraction under physiological condition.展开更多
文摘A novel into-plane rotating rnicromirror actuated by a hybrid electrostatic driving structure is presented. The hybrid driving structure is made up of a planar plate drive and a vertical comb drive. The device is fabricated in SOI substrate by using a bulk-and-surface mixed silicon micromachining process. As demonstrated by experiment, the novel driving structure can actuate the mirror to achieve large-range continuous rotation as well as spontaneous 90°rotation induced by the pull-in effect. The continuous rotating range of the micromirror is increased to about 46° at an increased yielding voltage. The measured yielding voltages of the mirrors with torsional springs of 1 and 0.5μm in thickness are 390 - 410V and 140 - 160V, respectively. The optical insertion loss has also been measured to be --1.98dB when the mirror serves as an optical switch.
基金National Natural Science Foundation of China(Grant No.20872144)
文摘Interaction of a drug molecule with human serum albumin （HSA） is usually studied by fluorescence responses of the ligand or/and the single tryptophan residue （Trp-214） of the protein, but qualitative spectral information may lead to multiple conclusions. In this work, we report a study on the interaction of hematoporphyrin monomethyl ether （HMME） with human serum albumin （HSA）, using the environment-sensitive spectra of HMME and reaction-induced fluorescence response of Trp-214. Particularly, the single kinetic parameter, the linear slope, was derived from the concentration-dependent absorbance or fluorescence of HMME in a certain solvent. A quantitative change in the slope at [HMME]/[HSA] = 1 ： 1 clearly demonstrated a specific binding of HMME to site I. The microenvironment in site I may be comparable to that in DMSO solvent, because of the similarity of the slope. Linear correlation of the fluorescence to the absorbance of HMME in site I indicates that the energy transfer is not responsible for Trp-214 fluorescence quenching but an electron transfer may be possible. In addition, much higher rate observed for the binding of HMME or 2-taurine-substituted HB （THB） with HSA than that of hypocrellin B was due to the electrostatic attraction under physiological condition.
