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111.
Hao Hongmiao Huang Sumei Chen Aixi 《International Journal of Theoretical Physics》2021,60(8):2766-2777
The strong coupling between a macroscopic mechanical oscillator and a cavity field is essential for many quantum phenomena in a cavity optomechanical system. In this work, we discuss the normal mode splitting in a cavity optomechanical system with a cubic nonlinear movable mirror. We study how the mechanical nonlinearity affects the normal-mode splitting behavior of the movable mirror and the output field. We find that the mechanical nonlinearity can increase the peak separation in the spectra of the movable mirror and the output field. We also find that the heights and linewidths of the two peaks are very sensitive to the mechanical nonlinearity.
相似文献112.
International Journal of Theoretical Physics - Quantum private comparison (QPC) can tell us whether two users’ private data are equal or not by quantum technology without disclosing privacy... 相似文献
113.
A new ESIPT-based fluorescent probe, PHC2, for the detection of hypochlorous acid has been rationally designed and developed. Endowed by the specific reaction between hypochlorous acid and phenyl azo group, PHC2 features high degree of selectivity and sensitivity for HClO with a low detection limit (13.2 nM) under physiological conditions in neutral aqueous solution. 相似文献
114.
Shape memory polymers (SMPs) have received great attention and scientific interest in widespread technological development during last few decades. Besides the development of novel SMPs, various techniques have been practiced for characterization of shape memory effect (SME) of SMPs. In this study, the shape memory effect and recovery stress property of the carbon nanotube (CNT)/waterborne epoxy (WEP) nanocomposites below and above the glass transition temperature (Tg) of the nanocomposites and under isostrain and isostress were systematically investigated via thermal mechanical analysis (TMA), respectively. The experimental results showed that the nanocomposites exhibit excellent shape memory effect. The shape memory fixity and recovery ratios were approximately 100% even below glass transition temperature (Tg). A remarkable point is that the strain of the nanocomposites suddenly increased with the temperature decreasing in a certain period of the heating-cooling cycles under isostress condition and the strain increment increased with temperature in general. Especially at low temperature, the recovery stress was very sensitive to temperature under isostrain condition of ±0.25 °C temperature with differential of 25.5 °C developed pressure difference of 0.20 MPa. Moreover, TMA is a practical method for quantifying the SME and recovery stress properties of SMPs and their composites. 相似文献
115.
This investigation examines the transient deformation and heat generation of a solid polyurethane subjected to dynamic compression. A special method is presented to prepare the solid polyurethane from raw materials which are commonly used to make polyurethane foams. Testing methods including infrared spectrum, differential scanning calorimetry, quasi-static and dynamic compression were applied to study the basic physical properties of the solid polyurethane. High-speed optical and infrared imaging systems are used to obtain visual and thermo-graphic images during impact tests. Under quasi-static compression, the solid polyurethane presents a good performance in toughness. This is confirmed by its Poisson's ratio. Under impact compression, the adiabatic heat generation are identified statistically. Temperature distribution confirms the fact of transient heat generation in specimens. Adiabatic self-heating mechanism provides a consideration to understand the negative strain-rate effect and post-yield softening effect found in the solid polyurethane. Mechanical properties including quasi-static and dynamic responses are related with the composition of molecular and structure of polymer. 相似文献
116.
Application of in-plasma catalysis and post-plasma catalysis for methane partial oxidation to methanol over a Fe2O3-CuO/γ-Al2O3 catalyst 总被引:1,自引:0,他引:1
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Methane partial oxidation to methanol (MPOM) using dielectric barrier discharge over a Fe2O3-CuO/γ-Al2O3 catalyst was performed. The multicomponent catalyst was combined with plasma in two different configurations, i.e., in-plasma catalysis (IPC) and post-plasma catalysis (PPC). It was found that the catalytic performance of the catalysts for MPOM was strongly dependent on the hybrid configuration. A better synergistic performance of plasma and catalysis was achieved in the IPC configuration, but the catalysts packed in the discharge zone showed lower stability than those connected to the discharge zone in sequence. Active species, such as ozone, atomic oxygen and methyl radicals, were produced from the plasma-catalysis process, and made a major contribution to methanol synthesis. These active species were identified by the means of in situ optical emission spectra, ozone measurement and FT-IR spectra. It was confirmed that the amount of active species in the IPC system was greater than that in the PPC system. The results of TG, XRD, and N2 adsorption-desorption revealed that carbon deposition on the spent catalyst surface was responsible for the catalyst deactivation in the IPC configuration. 相似文献
117.
Meihua Wang Jin Cai Lei Huang Zhengbin Lv Yaozhou Zhang Zhinan Xu 《Applied biochemistry and biotechnology》2010,162(7):2027-2036
The bioactivity of swollenin is beneficial to cellulose decomposition by cellulase despite the lack of hydrolytic activity
itself. In order to improve the productivity of swollenin, the effects of culture conditions on the expression level in recombinant
Aspergillus oryzae were investigated systematically. With regard to the bioactivity of swollenin, glycerin and peanut meal were the optimal
carbon or nitrogen source, respectively. The highest level production of swollenin (50 mg L−1) was attained after 88 h cultivation with the initial pH of 5.6 in the culture medium. Then the soluble swollenin was effectively
purified from the cultural supernatant by ammonium sulfate precipitation and cationic exchange chromatography with recovery
yield of 53.2%. The purified swollenin was fully bioactive due to its strong synergistic activity with cellulose. 相似文献
118.
Telomere maintenance and telomerase reactivation is essential for the transformation of most human cancer cells. Telomere
shortening to the threshold length, mutations of the telomere-associated proteins, and/or telomerase RNA lead to telomeric
dysfunction and therefore genomic instability. Telomerase up-regulation in 85% of human cancer cells has become a hallmark
of cancers, hence a promising target for anticancer therapy. In this review, we discuss the mechanism of cancer due to telomere
dysfunction and the resulting biological effects, the control of telomerase activity, and the new developments in cancer therapies
targeting telomere and telomerase. 相似文献
119.
Y.F. Yuan X.H. Xia J.B. Wu J.L. Yang Y.B. Chen S.Y. Guo 《Electrochemistry communications》2010,12(7):890-893
Hierarchically ordered porous nickel oxide array film was prepared by electrodeposition through monolayer polystyrene spheres template. The as-prepared film had a highly porous structure of interconnected macrobowls array possessing nanopores. As anode material for lithium ion batteries, the porous array NiO film exhibited weaker polarization, higher coulombic efficiency and better cycling performance in comparison with the dense NiO film. After 50 cycles, the discharge capacity of porous array NiO film was 518 mAh g? 1 at 1 C rate, higher than that of the dense NiO film (287 mAh g? 1). The enhancement of the electrochemical properties was due to the unique hierarchical porous architecture, which provided fast ion/electron transfer and alleviated the structure degradation during the cycling process. 相似文献
120.
Y. H. Fan Y. F. Wang C. F. Bi Q. Wang X. Zhang X. Y. Liu 《Russian Journal of Coordination Chemistry》2010,36(7):509-513
A new Schiff base ligand C19H13NO5(H2L) was synthesized using 2-aminoterephthalic acid and 2-hydroxy-1-naphthaldehyde. A complex of this ligand [Cu(C19H11NO5)(C2H6O)] n was synthesized and characterized by IR, UV, fluorescence spectroscopy and X-ray diffraction single-crystal analysis. The crystal crystallizes in the monoclinic system, space group Pbca with a = 8.7745(18), b = 18.613(4), c = 24.644(5) Å, V = 4024.9(14) Å3, Z = 8, F(000) = 1816, S = 1.009, ρ calcd = 1.462 g cm?3, μ = 1.122 mm?1, the final R = 0.0477 and wR = 0.1594 for 4609 observed reflections (I > 2σ(I)). The Cu(II) is five-coordinated by one N atom and two O atoms from the Schiff base ligand and two carboxylate O atoms from another two ligands to form a distorted square-pyramidal geometry. Each ligand serves as a bridging ligand to link Cu2+ ions, leading to a two-dimensional coordination polymer. The fluorescence properties of the ligand and complex were also studied. The ligand shows strong fluorescence, and the fluorescence intensity is weakened after the Cu(II) complex formed. 相似文献