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Hybridization of Mg-doped ZnO and reduced graphene oxide(MZO–RGO) were synthesized through one pot reaction process. Crystallization of MZO–RGO upon thermal decomposition of the stearate precursors was investigated by X-ray diffraction technique. XRD studies point toward the particles size with 10–15 nm,which was confirmed by transmittance electronic microscopy,and also indicates that graphene oxide has been directly reduced into its reduced state graphene during the synthesis. Graphene hybridized MZO photocatalyst showed enhanced catalytic activity for the degradation of methylene blue(MB). The degree of photocatalytic activity enhancement strongly depended both on the coverage of graphene on the surface of MZO nanoparticles and the Mg doping concentration. The sample of 2 wt% graphene hybridized 5 at% Mg-doped ZnO showed the highest photocatalytic activity,which remained good photocatalytic activity after nine cycling runs.  相似文献   
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The molten eutectic mixture of magnesium,sodium and potassium chlorides(Mg Cl2–Na Cl–KCl) has inappreciable solubility for oxide ions,and can help disengage a carbon anode from the oxide ions generated at a metal oxide cathode,and effectively avoid carbon dioxide formation.This "disengaging strategy" was successfully demonstrated in electro-reduction of solid oxides of zirconium and tantalum.It has led to significantly higher current efficiency(93%),and lower energy consumption(1.4 k W h kg 1) in electrolysis of tantalum oxide to tantalum metal compared to the conventional electrolysis in molten calcium chloride(e.g.78% and 2.4 k W h/kg-Ta).  相似文献   
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郭桂村  李臣 《中国西部科技》2010,9(19):77-78,66
本文运用文献资料法和逻辑归纳法,用社会学的视角对现代社会中年人高工作压力与体育锻炼的冲突进行分析,通过对现代生产、生活方式对中年人的生活身体影响,和中年人自身年龄段的身心特征的分析,进一步揭示冲突产生的原因,从而得出解决中年人这一冲突的对策,并进一步总结出本文的结论及建议,增强中年人对合理的体育锻炼和工作之间的冲突关系深层认知,从而找到一种行之有效的解决矛盾冲突的方法,使工作与锻炼之间达到良性的平衡,从而更好的满足中年人自身的发展需要,使他们能更好的发挥社会建设中流砥柱的作用。  相似文献   
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Series compounds Ca_3(Co_(0.9)M_(0.1))_2O_6(M = Co,Fe,Mn,Ni) with hexagonal crystal structure were prepared by sol-gel route as the cathode materials for solid oxide fuel cells(SOFCs).Effects of the varied atomic compositions on the structure,electrical conductivity,thermal expansion and electrochemical performance were systematically evaluated.Experimental results showed that the lattice parameters of Ca_3(Co_(0.9)Fe_(0.1))_2O_6and Ca_3(Co_(0.9)Mn_(0.1))_2O_6 were both expanded to certain degree.Electron-doping and hole-doping effects were expected in Ca_3(Co_(0.9)Mn_(0.1))_2O_6and Ca_3(Co_(0.9)Ni_(0.1))_2O_6 respectively according to the chemical states of constituent elements and thermal-activated behavior of electrical conductivity.Thermal expansion coefficients(TEC) of Ca_3(Co_(0.9)M_(0.1))_2O_6 were measured to be distributed around 16×10~(-6)K~(-1) and compositional elements of Fe,Mn,and Ni were especially beneficial for alleviation of the thermal expansion problem of cathode materials.By using Ca_3(Co_(0.9)M_(0.1))_2O_6 as the cathodes operated at 800 ℃,the interfacial area-specific resistance varied in the order of M = Co M = Fe M = Ni M = Mn,and the over-potential increased in the order of M = Fe ≈ M = Co M = Mn M = Ni.Among all of these compounds,Ca_3(Co_(0.9)Fe_(0.1))_2O_6 showed the best electrochemical performance and the power density as high as ca.500 mW cm~(-2) at800 ℃ achieved in the single cell with La_(0.8)Sr_(0.2)Ga_(0.83)Mg_(0.17)O_(2.815) as electrolyte and Ni-Ce_(0.8)Sm_(0.2)O_(1.9) as anode.Ca_3(Co_(0.9)M_(0.1))_2O_6(M = Co,Fe,Mn,Ni) can be used as the cost-effective cathode materials for SOFCs.  相似文献   
5.
在中国古典文学作品中,男性用自己的生理需求和审美标准来诠释对女性的理解和期望,规范和约束着女性的精神、意志和身体,使女性沦为男性的附庸,失去自身存在的价值。但人类的生存和发展需要两性和谐相处和男女之间进行平等的精神对话与交流,于是,在浩瀚的文学典籍中便出现了一些为女性呐喊和描述女性自主意识苏醒的篇章。五四运动之后,轰轰烈烈的女性解放运动,伴随着民族解放运动的高涨而拉开了帷幕,作家们从不同的侧面和角度,深入发掘女性受压迫的根源,创造了一个又一个生动的女性文学形象,为女性解放运动的前行指明了道路。21世纪的女性解放运动,似乎不如五四运动时期那么轰轰烈烈,但在文学作品中,依旧浮现出女性在社会、职场和家庭等压力之下的呐喊与奋进的身影。  相似文献   
6.
不对称信息条件下的风险投资实物期权评价   总被引:2,自引:0,他引:2  
李珏  杨青 《系统工程》2008,26(4):121-123
研究不对称信息条件下的风险投资实物期权评价问题,结合实物期权理论与委托代理理论构建了理论模型,求出了最优合约安排,并对逆向选择问题对风险投资期权评价的影响进行分析.  相似文献   
7.
结合传统的角点检测算法,提出一种基于高斯金字塔匹配的尺度不变特征点提取算法PBSI,首先建立高斯金字塔,在每层图像中检测Harris角点,根据高斯尺度理论自上而下找到它们在不同层的对应点,所有层上都有的匹配点就是最终的尺度不变特征点.实验结果表明本文算法具有计算简单、抗噪声能力强、稳定性好的优点.  相似文献   
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