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Z X Zhao

Publications and source records attributed to Z X Zhao.

8 recordsLinked to original sources
PubMed2005

Multiple bosonic mode coupling in the electron self-energy of (La2-xSrx)CuO4.

High resolution angle-resolved photoemission spectroscopy data along the (0,0)-(pi,pi) nodal direction with significantly improved statistics reveal fine structure in the electron self-energy of the underdoped (La2-xSrx)CuO4 samples in the normal state. Fine structure at energies of (40-46) meV and (58-63) meV, and possible fine structure at energies of (23-29) meV and (75-85) meV, have been identified. These observations indicate that, in (La2-xSrx)CuO4, more than one bosonic modes are involved in the coupling with electrons.

Journal Article↗
PubMed2005

Impedance labelless detection-based polypyrrole protein biosensor.

A simple and sensitive electrochemical immunosensor with impedance labelless detection and novel data processing method was investigated. One-step copolymerization was used to electrochemically deposit an antibody impregnated polypyrrole film on a glassy carbon electrode surface for the immunosensor. Impedance measurements provided a labelless or reporterless method to detect antibody (Ab)-antigen (Ag) interactions. Dimensionless analysis was employed to successfully process the measured impedance data. Since the method derived unit impedance change to eliminate or reduce the variation of the bulk electronic properties of Ab/polypyrrole films, the signal to noise ratio (S/N) was significantly improved for high sensitivity and specificity. Nonspecific binding effect was studied by array electrode chips and was found out that the polypyrrole electrode without antibody attachment had much stronger nonspecific binding effect than the Ab/polypyrrole electrode; incubation followed by thoroughly washing significantly reduced the nonspecific interference. 10 pg/ml detection limit and superior specificity were achieved by the method, demonstrating a highly sensitive labelless immunosensor in comparison with the detection limit of ng -microgram/ml for the reported polypyrrole based immunosensors. The electrochemical immunosensors presented in this paper, due to its simplicity, low cost, high sensitivity and superior specificity, could be an invaluable tool for clinical diagnostics and could have potential applications in drug discovery, environmental and food analysis.

Antibodies↗
PubMed2004

Dichotomy between nodal and antinodal quasiparticles in underdoped (La2-xSrx)CuO4 superconductors.

High resolution angle-resolved photoemission measurements on an underdoped (La(2-x)Srx)CuO4 system show that, at energies below 70 meV, the quasiparticle peak is well defined around the (pi/2,pi/2) nodal region and disappears rather abruptly when the momentum is changed from the nodal point to the (pi,0) antinodal point along the underlying "Fermi surface." It indicates that there is an extra low energy scattering mechanism acting upon the antinodal quasiparticles. We propose that this mechanism is the scattering of quasiparticles across the nearly parallel segments of the Fermi surface near the antinodes.

Journal Article↗
PubMed2003

Probing molecular dynamics at attosecond resolution with femtosecond laser pulses.

The kinetic energy distribution of D+ ions resulting from the interaction of a femtosecond laser pulse with D2 molecules is calculated based on the rescattering model. From analyzing the molecular dynamics, it is shown that the recollision time between the ionized electron and the D+2 ion can be read from the D+ kinetic energy peaks to attosecond accuracy. We further suggest that a more precise reading of the clock can be achieved by using shorter fs laser pulses (about 15 fs).

Journal Article↗
PubMed1992

[Antiarrhythmic effects of crebanine].

Crebanine (Cre) iv 5 mg/kg could convert BaCl2-induced arrhythmia into sinus rhythm in rats, and could significantly increase the tolerant dose of aconitine to produce ventricular fibrillation (VF) and cardiac arrest (CA) in rats. The drug could also decrease the incidence of VF and CA by CaCl2 in rats and by chloroform in mice, but had no protective effects on ouabain-induced arrhythmias in guinea pigs.

Aconitine↗
PubMed1990

[Diagnostic value of magnetic resonance imaging for syringomyelia].

Ten cases of syringomyelia confirmed by magnetic resonance imaging (MRI) were presented. The cavities in the spinal cord were of low signal on T1 weighted image (T1WI) and high signal on T2 weighted image (T2WI). The segments of the spinal cord with involved lesion resembled "bamboo joints" or were of "beaded" shape on sagittal section image and of "necklace" shape on cross section image. Size of the lesions in the spinal cord shown by MRI was larger than that judged by clinical symptoms. MRI can clearly show the position, size and shape of the cavities and other abnormal conditions. Results of this study show that MRI is the most useful diagnostic tool for syringomyelia. It should be emphasized that there was no dissociated impairment of pain and temperature and touch sensation in 40% of the patients and chronic spontaneous segmental pain was one of the important clinical characteristics of syringomyelia.

Adult↗