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81.
A novel milk-like Cu-thiourea colloid has been synthesized. Nanocrystalline quaternary copper sulfide Cu2FeSnS4 was obtained through the Cu-thiourea colloidal precursor cooperative conversion route at low temperature. The samples were characterized by means of X-ray powder diffraction, transmission electron microscopy, scanning electron microscopy, inductively coupled plasma atomic emission spectroscopy, and X-ray energy dispersive spectroscopy techniques. The reaction details and features were described and discussed.  相似文献   
82.
Thin layers of ceria were deposited on the surface of mica platelets in solution. The reaction of such particles with hydrogen sulfide yields a red colored special effect pigment. The ceria layer reacts with H2S to produce a variety of sulfide and oxysulfide phases. The reaction path discovered in situ by time and temperature resolved X-ray diffraction is CeO2→CeS2→C-Ce2S3→Ce10S14O. The reaction itself is extremely variable depending on gas flow, heating rates and decomposition atmospheres. Effects on the thin film are recorded by scanning electron microscopy (SEM) and revealed a destruction of the layer once red Ce10S14O was formed. The product layer then reveals the typical nonwetting behaviour of a liquid on a surface.  相似文献   
83.
A comparative study of gas sensing behavior of nanocrystalline nickel ferrite synthesized by micro-emulsion and hydrothermal method to liquefied petroleum gas (LPG) is presented. Nanocrystalline nickel ferrite synthesized by hydrothermal method indicated higher electrical conductivity and gas sensitivity at low operating temperature compared to nanocrystalline nickel ferrite synthesized by reverse micelle technique. This difference in the gas sensing behavior can be attributed to the presence of more oxygen vacancies (i.e. non-stoichiometry) in the hydrothermally synthesized nickel ferrite. Incorporation of palladium had a catalytic effect and the operating temperature was significantly reduced in both the samples. The higher operating temperature of the reverse micelle nickel ferrite material makes the sensor response speed faster (∼10 s) compared to the hydrothermally synthesized material (∼1 min).  相似文献   
84.
The thick film of Zn-Sb-O was prepared by coating the paste of nanoparticles mixture (Sb2O3:ZnO=1:3) on the alumina substrate, followed by sintering at 500-900 °C for 2 h in air. The electrical resistance and gas-sensing properties to benzene, alcohol and acetone of Zn-Sb-O films were found to be dependent on the change of phase structure caused by sintering temperature.  相似文献   
85.
The addition of metallic Ir and Pt to a fullerene-forming, atmospheric-pressure plasma reactor was found to influence the generation of carbonaceous products. It was observed that the added metals were efficiently dispersed into the plasma and that their presence increased the yield of fullerenes. The addition of Ir led to a noticeable shift in the fullerene distribution towards C60, whereas the addition of Pt increased the proportion of C60 oxides and decreased the proportion of higher fullerenes. Addition of Ir also caused a reduction of the soot particle size and the formation of a considerable quantity of carbon nanotubes.  相似文献   
86.
Combustion of bulk density Ti powder (containing 20 wt % TiN as a diluent) in a coflow of N2-Ar mixture was investigated upon variation in the nitrogen content of the gaseous mixture. The obtained data are believed to open up new horizons for fabrication of layered and composite ceramics by infiltration-mediated combustion.   相似文献   
87.
88.
高纯铝箔通常通过电化学扩面后用作铝电解电容器的阳极材料。利用铝箔(100)面隧道孔制备纳米模板。这种纳米模板的特点是制作简单、模板面积大,纳米阵列材料形状可控性强。还利用两步电化学侵蚀铝箔的特殊工艺,研制出纵横交错的TiO2纳米有序阵列材料。  相似文献   
89.
研究了富氧燃烧技术对梭式窑烧成的影响.研究结果表明,随着氧浓度从21%-30%的逐渐增加,CO总浓度和NO总浓度都先明显下降,后缓慢上升;节能效果在初始段较为明显,而后效果不明显;而实际烟气量与氧浓度成反比,与过剩空气系数成正比.  相似文献   
90.
A three-dimensional zinc phosphate compound with DFT topology, designated as ZnPO4-EU1, has been synthesized by an ionothermal approach from the system HF-ZnO–P2O5-choline chloride-imidazolidone. Ethylenediamine, derived from decomposition of the imidazolidone component of the deep-eutectic solvent (DES) itself, is delivered to the synthesis and serves as an appropriate template for ZnPO4-EU1. Experiments in which the synthesis conditions were varied showed that ZnPO4-EU1 may be prepared over a wide molar ratio of P/Zn = 0.55–13.0. Powder X-ray diffraction patterns have been obtained at intervals to track the crystallization process of this material. The experimental data show that Zn3(PO4)2 · 4H2O (a dense phase) was first isolated from the DES after reaction for 1 h. Subsequently, the pure phase of ZnPO4-EU1 was obtained with increasing crystallization time from 12 h to 72 h. The experimental results show that the nucleation and crystallization take place with relatively low levels of solvent degradation, demonstrating that zinc phosphate with a three-dimensional framework can be synthesized by in situ generation of an appropriate template using an unstable DES at high temperatures (150–200 °C).  相似文献   
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