Moderate-refractive-index dielectric nano-spheres are found to possess strong electric and magnetic dipole resonances in the visible region. Owing to the overlap of the electric and magnetic dipole ...resonances, moderate-refractive-index dielectric nanospheres exhibit directional forward scattering at the strongest scattering peak. Such directional scattering is experimentally observed on colloidal Cu sub(2)O nanospheres, which are readily prepared through wet-chemistry methods.
The contradiction between flammability and packing density is the technical bottleneck for combustible smoke agent.Herein,polyurethane(PU)foams with flammability and resilience were prepared with ...polyol and isocyanate as raw materials by chemical foaming method,then compounded with metal powders,polytetrafluoroethylene(PTFE),phthalic annychide(PA),etc.in a certain proportion and pressed into pyrotechnic grain to obtain eco-friendly combustion aerosols with compact density of about 1.15 g/cm3.The resulting combustion smoke agent combined the advantages of PU foam and pyrotechnic with easy ignition,large smoke production,long duration and low environmental pollution.The transmittance of aerosols for 532 nm and 1064 nm lasers was close to 0,and the EMI SE reached up to 65 dB and 35 dB in GPS band and X band,respectively.In addition,the resulting pyrotechnic grains exhibited good mechanical strength and elasticity for sample 1:25,with a compressive strength of 22 MPa and an elastic modulus of 195 MPa.The resulting combustion smoke agent is expected to play a potential role in the field of electromagnetic damage and protection.
In halide perovskites, electrons (holes) exist as electronic (hole) polarons, excitons, free and trapped electrons (holes). Six kinds of collisions could lead to annihilation of electron and hole, ...three of them involve polaron(s). In the annihilation channel of each collision process, there is a certain probability to form a dying pair which the average distance between electron and hole is smaller than a critical distance. The annihilation probability per unit time of a collision process is a product of the formation probability of the dying pair in the annihilation channel and the annihilation probability per unit time of dying pair. To annihilate an electronic (hole) polaron, electron (hole) must break away from the distorted environment, which can be achieved either by tunneling or by thermal activation. The observed temperature dependence of monomolecular and bimolecular recombination rates, the peak frequency and line width of photoluminescence spectrum are reproduced.
The spectral properties of spin–charge separation in one-dimensional electron–phonon interacting systems are investigated through the calculation of one-electron spectral functions of one-dimensional ...Holstein model away from half-filling. It is found that the retardation effect reduces weights of both spinon and holon collective excitations and increases the incoherent spectral weight at the same time, which makes the spin–charge separation invisible in the spectral function. Some differences between the spectral functions of the model at different filling are also discussed.
Gold nanorods have attracted intensive interest owing to their localized surface plasmon resonance properties and enormous potential applications. The transverse plasmon of Au nanorods is usually ...weaker than the longitudinal one, hampering certain plasmonic applications. Herein we report on the intensification of the transverse plasmon resonance by coating TiO
2
onto Au nanorods. The transverse plasmon mode of the resultant Au@TiO
2
nanorods with a sufficiently thick shell can be comparable to or even stronger than the longitudinal one in intensity. Moreover, both the transverse and longitudinal plasmon resonances of the Au@TiO
2
nanorods exhibit an asymmetric line shape on their scattering spectra. Electrodynamic simulations and analyses based on a coupled oscillator model suggest that the asymmetric line shape originates from the coupling between the Au core and TiO
2
shell. Apart from the shell thickness, the plasmonic properties of the Au@TiO
2
nanorods can also be tuned by the dimension of the Au nanorod core. In addition, the polarization-dependent light scattering from the individual Au@TiO
2
nanorods has also been investigated. These results will be of high importance for understanding the interactions between noble metals and semiconductors in plasmonic hybrid nanosystems, and for designing novel plasmonic nanostructures with desired optical properties and functions.
Au@TiO
2
nanorods are synthesized and found to possess similarly strong transverse and longitudinal plasmon resonances and exhibit double Fano resonances.
An increase in liver gluconeogenesis is an important pathological phenomenon in type 2 diabetes mellitus (T2DM) and oxymatrine is an effective natural drug used for T2DM treatment. The present study ...aimed to explore the effect of oxymatrine on gluconeogenesis and elucidate the underlying mechanism. Male Sprague-Dawley rats were treated with a high-fat diet and streptozotocin for 4 weeks to induce T2DM, and HepG2 cells were treated with 55 mM glucose to simulate T2DM
. T2DM rats were treated with oxymatrine (10 or 20 mg/kg weight) or metformin for 4 weeks, and HepG2 cells were treated with oxymatrine (0.1 or 1 µM), metformin (0.1 µM), or oxymatrine combined with MK-2206 (AKT inhibitor) for 24 h. Fasting blood glucose and insulin sensitivity of rats were measured to evaluate insulin resistance. Glucose production and uptake ability were measured to evaluate gluconeogenesis in HepG2 cells, and the expression of related genes was detected to explore the molecular mechanism. Additionally, the body weight, liver weight and liver index were measured and hematoxylin and eosin staining was performed to evaluate the effects of the disease. The fasting glucose levels of T2DM rats was 16.5 mmol/l, whereas in the control rats, it was 6.1 mmol/l. Decreased insulin sensitivity (K-value, 0.2), body weight loss (weight, 300 g), liver weight gain, liver index increase (value, 48) and morphological changes were observed in T2DM rats, accompanied by reduced AKT phosphorylation, and upregulated expression of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase). High-glucose treatment significantly increased glucose production and decreased glucose uptake in HepG2 cells, concomitant with a decrease in AKT phosphorylation and increase of PEPCK and G6Pase expression.
, oxymatrine dose-dependently increased the sensitivity of T2DM rats to insulin, increased AKT phosphorylation and decreased PEPCK and G6Pase expression in the liver, and reversed the liver morphological changes.
, oxymatrine dose-dependently increased AKT phosphorylation and glucose uptake of HepG2 cells subjected to high-glucose treatment, which was accompanied by inhibition of the expression of the gluconeogenesis-related genes, PEPCK and G6Pase. MK-2206 significantly inhibited the protective effects of oxymatrine in high-glucose-treated cells. These data indicated that oxymatrine can effectively prevent insulin resistance and gluconeogenesis, and its mechanism may be at least partly associated with the regulation of PEPCK and G6Pase expression and AKT phosphorylation in the liver.
Clathrate hydrideFm3-m-LaH10has been proven as the most extraordinary superconductor with the critical temperatureTcabove 250 K upon compression of hundreds of GPa in recent years. A general hope is ...to reduce the stabilization pressure and maintain the highTcvalue of the specific phase in LaH10. However, strong structural instability distortsFm3-mstructure and leads to a rapid decrease ofTcat low pressures. Here, we investigate the phase stability and superconducting behaviors ofFm3-m-LaH10with enhanced chemical pre-compression through partly replacing La by Ce atoms from both experiments and calculations. For explicitly characterizing the synthesized hydride, we choose lanthanum-cerium alloy with stoichiometry composition of 1:1. X-ray diffraction and Raman scattering measurements reveal the stabilization ofFm3-m-La0.5Ce0.5H10in the pressure range of 140-160 GPa. Superconductivity withTcof 175 ± 2 K at 155 GPa is confirmed with the observation of the zero-resistivity state and supported by the theoretical calculations. These findings provide applicability in the future explorations for a large variety of hydrogen-rich hydrides.
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