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x射线衍射对离子交换光色玻璃agx晶粒的研究  [PDF]
谢峻林
武汉理工大学学报 , 1995,
Abstract: ?agx晶粒尺寸是影响光色玻璃光色性的重要因素.对离子交换法光色玻璃,本文利用x射线研究了其表面agx晶粒的形成,并依据衍射峰宽化原理利用近似函数法对agx晶粒尺寸进行分析,继而讨论有关影响因素.
Ag/AgX(X=Cl,Br,I)等离子共振光催化剂的研究进展  [PDF]
王欢,崔文权,韩炳旭,梁英华
化工进展 , 2013,
Abstract: 银/卤化银[Ag/AgX(X=Cl,Br,I)]光催化剂作为一种新型光催化剂,由于在可见光区域具有明显的等离子共振效应从而显示了优异的可见光催化降解有机污染物的活性,引起了人们的极大重视。本文主要对Ag/AgX(X=Cl,Br,I)等离子体光催化剂的结构、光催化降解有机物机理、催化剂制备等进行了综述。Ag/AgX(X=Cl,Br,I)的活性普遍较高,通过半导体复合及形貌尺寸的控制,光催化性能得到进一步改善。进而论述了Ag/AgX体系等离子体共振光催化剂在工业染料废水处理上的应用现状,并对Ag/AgX(X=Cl,Br,I)等离子体光催化剂在高浓度、成分复杂污水体系处理中的应用进行了展望。
Investigations of the EPR parameters for the tetrahedral [FeX4]- clusters in AgX (X=Cl, Br)  [cached]
B.-T. Song,S.-Y. Wu,M.-Q. Kuang,Z.-H. Zhang
Condensed Matter Physics , 2012,
Abstract: The EPR parameters g factors and the superhyperfine parameters for the tetrahedral [FeX4]- clusters in AgX (X=Cl, Br) are theoretically investigated from the perturbation formulas of these parameters for a 3d5 ion under tetrahedra by considering both the crystal-field and charge transfer contributions.The related model parameters are quantitatively determined from the cluster approach in a uniform way. The g-shift Δg (=g-gs, where gs≈2.0023 is the spin only value) from the charge transfer contribution is opposite (positive) in sign and much larger in magnitude as compared with that from the crystal-field one. The importance of the charge transfer contribution increases rapidly with increasing the covalency and the spin-orbit coupling coefficient of the ligand and thus exhibits the order of AgCl < AgBr. The unpaired spin densities of the halogen ns, npσ and npπ orbitals are quantitatively determined from the related molecular orbital coefficients based on the cluster approach.
Investigations of the EPR parameters for the tetrahedral [FeX_4]^- clusters in AgX (X=Cl, Br)  [PDF]
B. -T. Song,S. -Y. Wu,M. -Q. Kuang,Z. -H. Zhang
Physics , 2012, DOI: 10.5488/CMP.15.13703
Abstract: The EPR parameters g factors and the superhyperfine parameters for the tetrahedral [FeX_4]^- clusters in AgX (X=Cl, Br) are theoretically investigated from the perturbation formulas of these parameters for a 3d^5 ion under tetrahedra by considering both the crystal-field and charge transfer contributions. The related model parameters are quantitatively determined from the cluster approach in a uniform way. The g-shift \Delta g (=g-g_s, where g_s\approx 2.0023 is the spin only value) from the charge transfer contribution is opposite (positive) in sign and much larger in magnitude as compared with that from the crystal-field one. The importance of the charge transfer contribution increases rapidly with increasing the covalency and the spin-orbit coupling coefficient of the ligand and thus exhibits the order of AgCl
High field magneto-transport study of YBa2Cu3O7-Agx (x = 0.0 to 0.20)  [PDF]
Poonam Rani,Anand Pal,V. P. S Awana
Physics , 2013, DOI: 10.1016/j.physc.2013.10.008
Abstract: We report high field (up to 13 Tesla) magneto transport R(T)H] of YBa2Cu3O7 (YBCO):Agx (x= 0.0, 0.1 and 0.2) composites. The transport properties are significantly improved by Ag doping on the insulating grain boundaries of YBCO. Pure and Ag diffused YBCO superconducting samples are synthesized through solid state reaction route. Both pure and Ag doped YBCO are superconducting at below 90K. Though, the Tc (R=0) of YBCO:Ag samples under applied field of 13 Tesla is around 65K, the same is 45K for pure YBCO under same applied field. The upper critical field [Hc2(0)], being estimated from R(T)H is around 70Tesla for pristine sample, and is above 190Tesla for Ag doped samples. The boarding of the resistive transition under applied magnetic field is comparatively less and nearly single step for Ag doped samples, while the same is clearly two step and relatively much larger for the pristine YBCO. The resistive broadening is explained on the basis of changed inter-granular coupling and thermally activated flux flow (TAFF). The TAFF activation energy (U0) is found to be linear with applied magnetic field for all the samples, but with nearly an order of magnitude less value for the Ag doped samples. Summarily, it is shown that inclusion of Ag significantly improves the superconducting performance of YBCO:Ag composites, in particular under applied field.
一维碳纤维承载AgX/TiO2(X=Br,I)三元复合材料的制备及光催化性能  [PDF]
梁海欧,白杰,于丹丹,张钦毓,李春萍
- , 2017,
Abstract: 摘要 利用静电纺丝技术结合高温煅烧过程制备碳纤维(CNFs)载体材料,进一步通过溶剂热和化学反应过程获得AgX/TiO2/CNFs(X=Br,I)复合光催化剂.利用X射线衍射(XRD)、扫描电子显微镜(SEM)、红外光谱(FTIR)等测试手段表征了材料的结构及形貌.通过在可见光下降解甲基橙考察了催化材料的光催化性能.结果表明,该复合材料具有高吸附性、良好的传导性以及较好的光敏性,从而使其具有较好的可见光催化活性;同时以一维碳纤维作为载体,使其更容易分离、回收,更具有实际应用价值
光色玻璃中agx颗粒度与光色性的关系  [PDF]
章新民
武汉理工大学学报 , 1986,
Abstract: ?采用x射线衍射线宽法和小角x射线散射技术进行了agx微晶的物相分析,测定了agx微晶颗粒尺寸及分布,研究了agx颗粒与变色深度和褪色速度的关系,建立了线性回归方程描述其关系,并从光色的电子过程出发,对其机理作了初步探讨。结果表明:
AC susceptibility study of superconducting YBa2Cu3O7:Agx bulk composites (x = 0.0-0.20): The role of intra and inter granular coupling  [PDF]
Poonam Rani,Rajveer Jha,V. P. S Awana
Physics , 2013,
Abstract: We report the effect of silver addition on superconducting performance of bulk YBCO (YBa2Cu3O7) superconductor. All the studied samples are prepared by conventional solid-state reaction method. Rietveld fitted X-ray diffraction data confirmed the single phase formation for all the studied samples. Detailed AC susceptibility measurements as a function of driven AC amplitude (1Oe-17Oe) of these samples revealed the enhancement of grains coupling with increasing Ag content in YBCO+Agx composite system. 10wt% Ag added YBCO superconductors exhibited the optimum inter granular coupling. The Scanning Electron Microscopy (SEM) observations indicate an increase in the grains connectivity in terms of narrow grain boundaries for doped samples. The average grain size is found to increase with Ag doping. It is concluded that limited addition of Ag in bulk YBCO superconductor significantly improves the grains coupling and as result optimum superconducting performance. YBCO+Ag composites could prove to be potential candidates for bulk superconducting applications of the studied high Tc system.
ACOUSTIC PROPERTIES OF AMORPHOUS SUPERIONIC CONDUCTOR (AgI)x(Ag4P2O7)1-x
非晶态快离子导体(AgI)x(Ag4P2O7)1-x的声学性质

WU KUN-YU,DING YI,YU WEN-HAI,
吴昆裕
,丁屹,俞文海

物理学报 , 1988,
Abstract: Amorphous superionic conductor (AgI)x(Ag4P2O7)1-x system has been obtained by means of the liquid nitrogen rapid quenching technique. The ultrasonic attenuation and velocity of longitudinal and transverse sound waves in the samples for Agl with mol concentration x = 0.50, 0.60, 0.67, 0.75, 0.80 were measured in the temperature range 77-300 K at the frequency of 2, 5, 10, 15 MHz. An anomalous strong ultrasonic absorption peak is observed at a temperature around 200-240 K with the rharacteristics of relaxation attenuation evidently. The attenuation peak was found to shifts to lower temperature and the peak attenuation value increases with increasing Agl content. In the experimental temperature region the internal friction QM-1 of longitudinal and transverse waves in the samples is almost equivalent. In the course of attenuation measurements the sound velocity, elastic moduli at room temperature and the dependence of sound velocity on Agl content were also measured. The experimental data fit satisfactorily the unified theory of low frequency fluctuation, dissipation and relaxation process (i.e. infrared divergence response theory, briefly called as IDR) proposed by Ngai. The apparent activation energy and infrared divergence exponent of the samples were presented.
Superionic to superionic phase change in water: consequences for the interiors of Uranus and Neptune  [PDF]
Hugh F. Wilson,Michael L. Wong,Burkhard Militzer
Physics , 2012, DOI: 10.1103/PhysRevLett.110.151102
Abstract: Using density functional molecular dynamics free energy calculations, we show that the body-centered-cubic phase of superionic ice previously believed to be the only phase is in fact thermodynamically unstable compared to a novel phase with oxygen positions in fcc lattice sites. The novel phase has a lower proton mobility than the bc phase and may exhibit a higher melting temperature. We predict a transition between the two phases at a pressure of 1 +/- 0.5 Mbar, with potential consequences for the interiors of ice giants such as Uranus and Neptune.
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