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Ming Han

Publications and source records attributed to Ming Han.

9 recordsLinked to original sources
PubMed2006

Implementation of a loss-compensated recirculating delayed self-heterodyne interferometer for ultranarrow laser linewidth measurement.

Ultranarrow laser linewidth measurement using an optimized loss- compensated recirculating delayed self-heterodyne interferometer is described. An experimental setup is constructed to measure subkilohertz laser linewidths. The system parameters are optimized to obtain the best beat signals. The experimental results agree well with the theoretical analysis. Two methods of linewidth interpretation are presented and analyzed based on the experimental results. It is proved that a loss-compensated recirculating delayed self-heterodyne interferometer is an effective tool for measuring an ultranarrow laser linewidth.

Journal Article↗
PubMed2006

High-speed fiber-optic spectrometer for signal demodulation of inteferometric fiber-optic sensors.

We demonstrated a spectrometer that is capable of acquiring the spectra from interferometric fiber-optic sensors at high speed. The high spectrum acquisition rate is enabled by transforming the spectral information from frequency domain to time domain using a dispersive element and high-speed data acquisition devices. Preliminary results show that the prototype system can record 10,000 frames of spectra per second and achieve a spectrum measurement resolution of 15 nm. Better performance could be realized by using a Raman amplifier and by optimizing the parameters of the system and data processing methods.

Journal Article↗
PubMed2006

Mode power distribution effect in white-light multimode fiber extrinsic Fabry-Perot interferometric sensor systems.

Theoretical and experimental results have shown that mode power distribution (MPD) variations could significantly vary the phase of spectral fringes from multimode fiber extrinsic Fabry-Perot interferometric (MMF-EFPI) sensor systems, owing to the fact that different modes introduce different extra phase shifts resulting from the coupling of modes reflected at the second surface to the lead-in fiber end. This dependence of fringe pattern on MPD could cause measurement errors in signal demodulation methods of white-light MMF-EFPI sensors that implement the phase information of the fringes.

Journal Article↗
PubMed2004

Exact analysis of low-finesse multimode fiber extrinsic Fabry-Perot interferometers.

A straightforward theory is presented to accurately model the light inferences in a low-finesse multimode fiber extrinsic Fabry-Perot (FP) interferometer. The effect on the fringe visibility of the gap length, sensor structure imperfections, and modal power distributions is explored. The analysis is particularly useful in the design and optimization of sensors that use an extrinsic FP cavity as the sensing element.

Journal Article↗
PubMed2004

Signal-processing algorithm for white-light optical fiber extrinsic Fabry-Perot interferometric sensors.

We present a novel signal-processing algorithm for single-mode optical fiber extrinsic Fabry-Perot interferometric sensors that can achieve both high-resolution, absolute measurement of the cavity length and a large dynamic measurement range simultaneously. The algorithm is based on an accurate model of the characteristics of a fiber-optic sensor that takes into account the phase shift that is due to the coupling of light reflected at the second surface to the lead-in fiber end.

Journal Article↗
PubMed2004

Physical and electrochemical characterizations of microwave-assisted polyol preparation of carbon-supported PtRu nanoparticles.

PtRu nanoparticles supported on Vulcan XC-72 carbon and carbon nanotubes were prepared by a microwave-assisted polyol process. The catalysts were characterized by transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy (XPS). The PtRu nanoparticles, which were uniformly dispersed on carbon, were 2-6 nm in diameter. All PtRu/C catalysts prepared as such displayed the characteristic diffraction peaks of a Pt face-centered cubic structure, excepting that the 2theta values were shifted to slightly higher values. XPS analysis revealed that the catalysts contained mostly Pt(0) and Ru(0), with traces of Pt(II), Pt(IV), and Ru(IV). The electro-oxidation of methanol was studied by cyclic voltammetry, linear sweep voltammetry, and chronoamperometry. It was found that both PtRu/C catalysts had high and more durable electrocatalytic activities for methanol oxidation than a comparative Pt/C catalyst. Preliminary data from a direct methanol fuel cell single stack test cell using the Vulcan-carbon-supported PtRu alloy as the anode catalyst showed high power density.

Carbon↗
PubMed2003

[Second-line Hycamtin in the treatment of lung cancer].

OBJECTIVE: To discuss the therapeutic effect and toxicity of second line Hycamtin for lung cancer patients. METHODS: Ten of these 21 patients had been treated with operation. All these 21 patients received second line Hycamtin treatment; given at the dose of 1.2 mg/m(2) per day, four consecutive days as one cycle and 21 days as one course. A total of 1 - 4 courses were given according to the patient's tolerance. Four of these 21 patients also received combination of cisplatin. RESULTS: Among the 13 un-operated patients, two patients showed CR, six showed PR, three SD and two PD, giving an effective rate of 62%. Among the 8 operated patients, seven showed SD but one developed distant metastasis. The 1-year survival rate was 88%. TOXICITY: leukopenia I-II degree 14 (66.7%), leukopenia III-IV degree 5 (23.8%), thrombocytopenia III-IV degree 1 (4.8%) and one patient died of high fever and neutocytopenia. Nausea 8 (38.1%), vomiting 3 (14.3%) and diarrhea 2 (9.5%) alopecia 4 (19.1%). Were the other side-effects. CONCLUSION: Hycamtin is indicated for second line therapy for lung cancer giving tolerable toxicity.

Adult↗