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91.
Tin oxide nanoparticles (SnO2 NPs) have been encapsulated in situ in a three‐dimensional ordered space structure. Within this composite, ordered mesoporous carbon (OMC) acts as a carbon framework showing a desirable ordered mesoporous structure with an average pore size (≈6 nm) and a high surface area (470.3 m2 g?1), and the SnO2 NPs (≈10 nm) are highly loaded (up to 80 wt %) and homogeneously distributed within the OMC matrix. As an anode material for lithium‐ion batteries, a SnO2@OMC composite material can deliver an initial charge capacity of 943 mAh g?1 and retain 68.9 % of the initial capacity after 50 cycles at a current density of 50 mA g?1, even exhibit a capacity of 503 mA h g?1 after 100 cycles at 160 mA g?1. In situ encapsulation of the SnO2 NPs within an OMC framework contributes to a higher capacity and a better cycling stability and rate capability in comparison with bare OMC and OMC ex situ loaded with SnO2 particles (SnO2/OMC). The significantly improved electrochemical performance of the SnO2@OMC composite can be attributed to the multifunctional OMC matrix, which can facilitate electrolyte infiltration, accelerate charge transfer, and lithium‐ion diffusion, and act as a favorable buffer to release reaction strains for lithiation/delithiation of the SnO2 NPs.  相似文献   
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In our previous paper, structural changes of selenium powders ground by a planetary ball mill at various rotational speeds were investigated for the nanostructural modification of particles using mechanical grinding process. The experimental results indicated that the amorphisation of Se by grinding accompanies lattice strain, and the lattice strain arises from impact energy which is more than an energy related to intermolecular interaction. In this paper, molecular dynamics simulations of selenium have been carried out under compressing conditions of various pressure strengths for obtaining information of the lattice strain at atomic level. Then, dynamical behaviour of atomic configuration has been discussed in this process. The structural disordering and formation of the structural defects were estimated by deviations of bond length and angle and the number of created defects before and after compressing from simulated results. The disordering took place during compressing at various pressure strengths, and the disordered atoms return to their initial positions at lower pressure. Stable disordered state and defects after the compression can however remain by compression at more than a certain pressure strength mainly associated with binding energy of selenium.  相似文献   
95.
Pressure reducing valves are widely used to maintain the pressure of gas reservoirs to specific values. In a normal valve, supply pressure is decompressed with an orifice structure. When compressed air passes through the orifice structure, considerable noise occurs at the downstream side. In this paper, we have developed a radial slit structure that can reduce pressure without noise. The noise is reduced by changing the orifice structure into the radial slit structure. The radial slit structure valve reduces pressure without noise by suppressing the generation of turbulence and shock wave at the downstream. The analysis of the flow in radial slit structure was achieved by CFD2000 software. The flow rate and pressure distribution were simulated and compared with the experimental result. To confirm the generation of shock wave, the flow of orifice and radial slit structure at the downstream was visualized by Schlieren photography method. A shock wave was generated in the orifice structure, but no shock wave was generated in the radial slit structure. Noise reduction efficiency was investigated by the experiment. The experiment apparatus was set up to JIS standards. The experimental results indicated that the noise level decreased by approximately 40 dB in the slit structure. It is confirmed that the radial slit structure has effectiveness for low noise in the pressure reducing flow. And, it is expected that it can be applied to various kinds of industrial fields.  相似文献   
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The rhodium catalyzed isomerization of α-, β-, and γ-silylated allyl alcohols has been successfully applied to the selective synthesis of acylsilane, α-silyl ketones, and β-silyl ketones, respectively.  相似文献   
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By using different gauges, the relativistic rates for the Kαα2(1s?2→2s?12p12?1) and the Kα2h(1s?2→1s?12p12?1) transitions are calculated for Ne, Ar, Ca, Fe and Cu. The problem in the use of the single configuration HF model is discussed.  相似文献   
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Summary Sodium ion-selective electrodes (Na+-ISE) were prepared by implanting Si+ and Li+ into alumina wafers and their characteristics were investigated. The alumina wafer had a thickness of 100 m and a diameter of 1.40 cm. The ionselective membrane was produced by ion-implanting of Li+ and Si+ on both sides of a single-crystal alumina wafer. The total doses of Li+ and Si+ were controlled to be the same, viz. 1013–1015 ions/cm2. The ion-implanted alumina wafer with 1014 or 4×1014 ions/cm2 of Li+ and Si+ showed better characteristics than the others.The response curves of the 1014 ions/cm2 implanted alumina wafer had a slope of 42 mV/pNa in a concentration range from 1–10–4mol/l. The full response achieved after about 1 min was reproducible. The proposed idea of producing Na+-ISE by ion-implantation technique was applied to functuate the gate surface of the field effect transitor to sodium ion. The sodium ion-sensitive FET (Na+-ISFET) prepared by implanting Li+ and Al+ at a dose of 5×1014 ions/cm2 showed a slope of 30 mV/pNa in a concentration range from 1–10–4mol/l.
Herstellung Na+-ionenselektiver Elektroden durch Einbau von Lithium und Silicium in Einkristall-Alumniumoxidblättchen und Anwendung zur Erzeugung von ISFET
Zusammenfassung Na+-selektive Elektroden wurden durch Einbau von Si+ und Li+ in Aluminiumoxidblättchen hergestellt und ihre Charakteristiken untersucht. Die Blättchen hatten eine Dicke von 100 m und einen Durchmesser von 1,40 cm. Ebenso wurde die Membran für einen ISFET hergestellt. Die Gesamtmenge von Li+ und Si+ wurde auf 1013–1015 Ionen/cm2 eingestellt, wobei sich bei 1014 oder 4×1014 Ionen/cm2 die beste Charakteristik ergab.Die Responsekurven der mit 1014 Ionen/cm2 versehenen Aluminiumoxidplättchen hatten eine Neigung von 42 mV/pNa in einem Konzentrationsbereich von 1–10–4mol/l. Der nach 1 min erhaltene volle Response war reproduzierbar. Die vorgeschlagene Technik wurde zur Einstellung der Gate-Oberfläche des Feldeffekt-Transistors auf Natriumion benutzt. Der Na+-sensitive FET (Na+-ISFET), der durch Einbau von Li+ und Al+ mit 5×1014 Ionen/cm2 hergestellt wurde, zeigte eine Neigung der Signalkurve von 30 mV/pNa in einem Bereich von 1–10–4mol/l.
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