Cui Da-Fu

Drug evaluations using a novel microphysiometer based on cell-based biosensors

Abstract This paper presents a novel microphysiometer based on cell-based biosensors for simultaneous measurements of several extracellular ion concentrations in living cells when treated with drugs. It can measure the extracellular acidification rate (ECAR) under the effects of the drug. Thus the relation between the cells’ metabolism and the activity of receptors can be explored, and the function of the drug can be analyzed. We used our system to measure the effects of some drugs on the nephridium and cardiac muscle cells of the suckling rat. As the microphysiometer works under regular cell culture conditions, cells can be repeatedly simulated with drugs to complete dose–response curve within a few hours. With the detection of a general parameter (extruded protons and ions), the system can be used to monitor the real-time process of the cells’ metabolism, observe the functional responses of different kinds of membrane-bound receptors and evaluate the drugs.

106.5 W high beam quality diode-side-pumped Nd:YAG laser at 1123 nm

We demonstrate a diode-side-pumped continuous wave (CW) Nd:YAG laser at 1123 nm with over 100 Ws output power and good beam quality. The resonator adopts convex-convex structure working in a thermally near unstable cavity. By precise coating design a single 1123 nm wavelength is delivered. Under the pumped power of 870 W, an output power of 106.5 W is obtained, corresponding to an optical-optical conversion efficiency of 12.2%. The beam quality of M(2) factor is measured to be 5.6. To the best of our knowledge, this is the highest output power with good beam quality for 1123 nm CW Nd:YAG laser.

Unit-Cell by Unit-Cell Epitaxial Growth of SrTiO3 and BaTiO3 Thin Films by Laser Molecular Beam Epitaxy

Atomically regulated unit-cell by unit-cell homoepitaxial SrTiO3 and heteroepitaxial BaTiO3 films were fabricated on SrTiO3(100) substrates by laser molecular beam epitaxy. The fine streak patterns and more than 1000 cycles undamping intensity oscillation were obtained by in situ reflection high-energy electron diffraction with precisely controlled intermittence between each unit-cell layer. The surface morphology of the films was examined by atomic force microscopy. The root-mean-square surface roughness of the films is about 0.1 nm.

33 W quasi-continuous-wave narrow-band sodium D-2a laser by sum-frequency generation in LBO

We demonstrate an all-solid quasi-continuous-wave (QCW) narrow-band source tunable to sodium D-2a line at 589.159 nm. The source is based on sum-frequency mixing between lasers at 1064 nm and 1319 nm in a LBO crystal. The 1064 nm and 1319 nm lasers are produced from two diode side-pumped Nd:YAG master oscillator power amplifier (MOPA) laser systems, respectively. A 33 W output of 589 nm laser is obtained with beam quality factor M-2 = 1.25, frequency stability better than +/- 0.2 GHz and linewidth less than 0.44 GHz. A prototype 589 nm laser system is assembled, and a sodium laser guided star has been successfully observed in the field test.

High-average-power third harmonic generation at 355 nm with CsB3O5 crystal

A 17.7 W average power output at 355 nm by the third harmonic generation (THG) of 1064 nm light has been obtained with the nonlinear optical crystal CsB3O5 (CBO). The fundamental light source is a diode-pumped Nd:YAG laser with a pulse duration of 70 ns and a repetition rate of 7 kHz. A CBO crystal cut for type-II PM angles is used in the experiment. The THG energy conversion efficiency with CBO is twice as large as that with LBO. As a THG crystal, CBO has better performance than that of LiB3O5 crystal (LBO).

Comparison of Nd:YAG Ceramic Laser Pumped at 885 nm and 808 nm

Laser performance of 1064 nm domestic Nd:YAG ceramic lasers for 885 nm direct pumping and 808 nm traditional pumping are compared. Higher slope efficiency of 34% and maximum output power of 16.5 W are obtained for the 885 nm pump with a 6 mm length 1 at.% Nd:YAG ceramic. The advantages for 885 nm direct pumping are discussed in detail. This pumping scheme for highly doping a Nd:YAG ceramic laser is considered as an available way to generate high power and good beam quality simultaneously.

Superconducting MgB2 Thin Films with Tc≈39 K Grown by Pulsed Laser Deposition

Superconducting MgB2 thin films were fabricated on Al2O3(0001) substrates under ex situ processing conditions. Boron thin films were deposited by pulsed laser deposition followed by a post-annealing process. Resistance measurements of the deposited MgB2 films show Tc of ~39 K, while scanning electron microscopy and x-ray diffraction analysis indicate that the films consist of well-crystallized grains with a highly c-axis-oriented structure.Superconducting MgB2 thin films were fabricated on Al2O3(0001) substrates under an ex-situ processing conditions. Boron thin films were deposited by pulsed laser deposition followed by a post-annealing process. Resistance measurements of the deposited MgB2 films show Tc of about 39K, while scanning electron microscopy and x-ray diffraction analysis indicate that the films consist of well-crystallized grains with a highly c-axis-oriented structure.

Sixth Harmonic of A Nd:YVO4 Laser Generation In KBBF for ARPES

We report that a deep ultraviolet (DUV) laser from the sixth harmonic of a 1064 nm laser has been firstly used as light source in an ultrahigh energy-resolution angle-resolved photoemission spectroscopy (ARPES). The wavelength is 177.3nm obtained by using the second harmonic KBe2BO3F2 crystal with a frequency tripled 1064nm Nd:YVO4 laser. The large flux (1014 – 1015 photons/s) and narrow line width (0.26meV) are suitable for the ultrahigh-energy resolution ARPES. The laser-ARPES can be a powerful tool to study the electronic structure at and near the Fermi level of the superconductor and correlated materials. The laser-ARPES has worked more than 500 h already.

Reducing Thermal Effect in End-Diode-Pumped Laser Crystal by Using a Novel Resonator

We report a new way, i.e. double-end-pumping, to extend the stability range of a laser resonator, in advantage of making the thermal loading be effectively divided between the ends of the laser crystal to reduce the thermal effect, thus to extend the stability range. Using this new way, we experimentally obtained a 2.7-W cw laser source at 671 nm by intracavity frequency doubling of 1342 nm of a Nd:YVO4 laser based on the nonlinear crystal LiB3O5. The maximum pump power is 28 W, which is higher than 13 W of the single-end-pumping.

High-power blue light generation by external frequency doubling of an optical parametric oscillator

We report on an all-solid-state high-power quasi-continuous blue light source by the frequency doubling of a signal wave from an optical parametric oscillator (OPO). A 50-mm-long LiB3O5 (LBO) crystal is used for the OPO, which is pumped by a diode-pumped Nd:YAG green laser (10 kHz, 50 ns). Tunable blue emission in a new nonlinear crystal BiB3O6 (BiBO) is obtained with a wavelength range from 450 to 495 nm. The average power of the signal output is as high as 9.3 W from 924 to 970 nm. The maximum output of the blue laser with the second harmonic walk-off compensation is 1.3 W average power at 470 nm for 6.2 W of OPO signal light at 940 nm.