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1.
介绍了河南大学图书馆开展的"馆级科研项目"活动的概况和意义,并提出了进一步完善该项活动的建议。  相似文献   
2.
In this study, based on the first-principles calculations, we systematically investigated the electronic and magnetic properties of the transition metal–oxide-incorporated 2D g-C3N4 nanosheet (labeled C3N4– TM–O, TM= Sc–Mn). The results suggest that the TM–O binds to g-C3N4 nanosheets strongly for all systems. We found that the 2D C3N4–TM–O framework is ferromagnetic for TM= Sc, Ti, V, Cr, while it is antiferromagnetic for TM= Mn. All the ferromagnetic systems exhibit the half-metallic property. Furthermore, Monte Carlo simulations based on the Heisenberg model suggest that the Curie temperatures (Tc) of the C3N4–TM–O (TM= Sc, Ti, V, Cr) framework are 169 K, 68 K, 203 K, and 190 K, respectively. Based on Bader charge analysis, we found that the origin of the half-metallicity at Fermi energy can be partially attributed to the transfer of electrons from TM atoms to the g-C3N4 nanosheet. In addition, we found that not only electrons but also holes can induce half-metallicity for 2D g-C3N4 nanosheets, which may help to understand the origin of half-metallicity for graphitic carbon nitride.  相似文献   
3.
风力测定仪     
王会丽 《物理通报》2006,(12):55-56
风力测定仪用来测量风力的大小,它是根据滑动变阻器改变线路中电流的原理制成的测量类仪器.通过风力的大小改变滑动变阻器的阻值,从而引起线路中电流的变化,由电流表的示数指示风力的大小.本文通过两个例题的形式,从物理的角度来讨论风力测定仪的构造、原理和风力刻度的标定.  相似文献   
4.
总结和介绍了《中国信息化》一书的重点内容及主要观点,认为《中国信息化》总结了近10年来中国信息化的探索和实践,融理论性、实践性和权威性于一体,在指导信息化实践、普及信息化知识和增强信息化意识方面具有重要作用。  相似文献   
5.
In order to obtain a comprehensive understanding of both thermodynamics and kinetics of water dissociation on TiO2, the reactions between liquid water and perfect and defective rutile TiO2 (110) surfaces were investigated using ab initio molecular dynamics simulations. The results showed that the free-energy barrier (~4.4 kcal/mol) is too high for a spontaneous dissociation of water on the perfect rutile (110) surface at a low temperature. The most stable oxygen vacancy (Vo1) on the rutile (110) surface cannot promote the dissociation of water, while other unstable oxygen vacancies can significantly enhance the water dissociation rate. This is opposite to the general understanding that Vo1 defects are active sites for water dissociation. Furthermore, we reveal that water dissociation is an exothermic reaction, which demonstrates that the dissociated state of the adsorbed water is thermodynamically favorable for both perfect and defective rutile (110) surfaces. The dissociation adsorption of water can also increase the hydrophilicity of TiO2.  相似文献   
6.
采用低温电炉法对传统高温膨胀制备膨胀石墨的方法进行优化,并对其在染料废水处理中的应用进行了研究。考察了氧化剂、插层剂和氧化次数对膨胀体积的影响,并使用SEM、XRD、FT-IR对样品进行外观形貌和结构表征。研究结果表明:使用高锰酸钾-磷酸-硝酸氧化插层体系一次氧化下并使用低温电炉法进行膨化的效果最好,制备出的膨胀石墨样品膨胀体积为390 m L/g,比表面积252 m2/g。在对活性黄模拟染料废水处理的实验中,考察了膨胀石墨用量、活性黄浓度和温度3个因素对于活性黄模拟染料废水吸附效果的影响,结果表明:对于质量浓度为250 mg/L的活性黄废水,膨胀石墨的最大吸附量可达到180 mg/g;当膨胀石墨添加量为2.0 g/L时处理效果最佳,去除率达到65%;而温度对于吸附过程影响较小。  相似文献   
7.
专利信息服务已经成为高校图书馆新的服务增长点。河南省高校图书馆开展专利信息服务是国家和地区知识产权战略实施、高校知识产权综合能力提升和高校图书馆服务转型的需要。河南省高校图书馆在专利信息资源、服务技术和服务团队方面已初步具备开展专利信息服务的条件。因此,河南省高校图书馆有必要且有条件承担起专利信息服务的责任,为创新型国家建设贡献自己的力量。  相似文献   
8.
介绍了知识协同的内涵,分析了图书馆科技查新知识协同的概念和类型,提出了加强图书馆科技查新内外部知识协同的对策.  相似文献   
9.
采用相同反离子协同磷酸活化法, 以十六烷基三甲基溴化铵(CTAB)-KBr为复合改性剂, 制备了一种高效吸附剂复合改性膨胀石墨(M-EG), 通过扫描电子显微镜(SEM)、 傅里叶变换红外光谱(FTIR)及X射线电子能谱(XPS)等对膨胀石墨(EG)和改性膨胀石墨(M-EG)的形貌结构、 组成和价态进行了表征, 考察了EG和M-EG对酸性艳蓝染料废水的处理效果. 结果表明, 复合改性后的膨胀石墨孔隙度变大, 表面含氮和溴官能团增多. 吸附剂M-EG对酸性艳蓝染料废水具有较高的吸附性能, 在pH=1.0及30 ℃条件下对染料的去除率达到94.13%; EG符合二级动力学吸附模型, 用Langmuir等温线方程拟合效果较好; M-EG符合二级吸附动力学方程, 同时符合Langmuir和Freundlich等温吸附模型; M-EG的吸附动力学常数大于EG吸附动力学常数.  相似文献   
10.
In order to obtain a comprehensive understanding of both thermodynamics and kinetics of water dissociation on TiO2, the reactions between liquid water and perfect and defective rutile TiO2 (110) surfaces were investigated using ab initio molecular dynamics simulations. The results showed that the free-energy barrier (~4.4 kcal/mol) is too high for a spontaneous dissociation of water on the perfect rutile (110) surface at a low temperature. The most stable oxygen vacancy (Vo1) on the rutile (110) surface cannot promote the dissociation of water, while other unstable oxygen vacancies can significantly enhance the water dissociation rate. This is opposite to the general understanding that Vo1 defects are active sites for water dissociation. Furthermore, we reveal that water dissociation is an exothermic reaction, which demonstrates that the dissociated state of the adsorbed water is thermodynamically favorable for both perfect and defective rutile (110) surfaces. The dissociation adsorption of water can also increase the hydrophilicity of TiO2.  相似文献   
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