Q.F. Meng
,
K.R. Liu
,
L. Jiang
,
Q. Han
,
J.S. Chen
,
X.J. Wei
金属学报(英文版)
The nano-crystal composite WO3-TiO2 photocatalyst was prepared by ultrasonic assisted sol-gel process. The e®ects of various factors, such as the crystal form, the
substrates, the pH, the dissolved oxygen and the ultrasonic on the photocatalytic activity were investigated in view of the photodegradation of Rhodamine B. The results
show that the crystal form of WO3-TiO2 film with highest photocatalytic activity is
rutile. The introduction of ultrasonic to the course of preparation can accelerate the
deposit time of the sol and increase the photocatalytic activity signi¯cantly in view of
the highest photodegradation of Rhodamine B being 72.7% in 5 hours. The porous
titanium plate is the most suitable substrate in four kinds of investigated materials.
Meanwhile the smaller the pH and the higher the concentration of the dissolved oxygen
in the solution is, the higher the photodegradation is.
关键词:
ultrasonic
,
null
,
null
,
null
Q. Han
,
J.S. Chen
,
K.R. Liu
金属学报(英文版)
NiSCo catalytic cathodes were obtained by electrodeposition in a typical Watt cellwith addition of NH2 CSNH2 and CoCl2. Using CoCl2 concentration, current density,temperature and pH value as main factors, an orthogonal experiment was designed todetermine the optimum technological conditions according to HER overpotentials. Theoptimum technological conditions were obtained from the minimum HER overpoten-tial -70m V. The corresponding electrochemical parameters (Tafel slope b, exchangecurrent density to) were determined by steady-state polarization curves. The contentof S, Co and its microstructure were measured by EPMA and XRD.
关键词:
NiSCo alloy
,
null
,
null
Communications in Theoretical Physics
By means of both a theory for pressure-induced shifts (PS) of energy spectra and a theory for shifts of energy spectra due to electron-phonon interaction (EPI), the 'pure electronic' PS and the PS due to EPI of R-1 line, R-2 line, and U band of GSGG:Cr3+ at 300 K have been calculated, respectively. The calculated results are in good agreement with all the experimental data. Their physical origins have also been explained. It is found that the mixing-of degree \t(2)(2)(T-3(1))e(4)T(2)> and \t(2)(3) 2E> base-wavefunctions in the wavefunctions of R-1 level of GSGG:Cr3+ at 300 K is remarkable under normal pressure, and the mixing-degree rapidly decreases with increasing pressure. The change of the mixing-degree with pressure plays a key role not only for the 'pure electronic' PS of R-1 line and R-2 line but also the PS of R-1 line and R-2 line due to EPI. The pressure-dependent behaviors of the 'pure electronic' PS of R-1 line (or R-2 line) and the PS Of R-1 line (or R-2 line) due to EPI are quite different. It is the combined effect of them that gives rise to the total PS of R-1 line (or R-2 line). In the range of about 15 kbar similar to 45 kbar, the mergence and/or order-reversal between t(2)(2)(T-3(1))e(4)T(2) levels and t(2)(32)T(1) levels take place, which cause the fluctuation of the rate of PS for t(2)(2)(T-3(1))e(4)T(2) (or t(2)(3) T-2(1)) with pressure. At 300 K, both the temperature-dependent contribution to R-1 line (or R-2 line or U band) from EPI and the temperature-independent one are important.
关键词:
high-pressure effect;spin-orbit interaction;electron-phonon;interaction;d orbital;coupling between t(2)(2)(3T(1))e(4)T(2) and;t(2)(32)E;tunable laser crystal;theoretical calculations;temperature-dependence;thermal broadenings;garnet crystals;cr3+ ions;r-line;cr-3+;luminescence;ruby;spectroscopy
Communications in Theoretical Physics
By means of both a theory for pressure-induced shifts (PS) of energy spectra and a theory for shifts of energy spectra due to electron-phonon interaction (EPI), the "pure electronic" PS and the PS due to EPI of R-1 line of GSGG:Cr3+ at 70 K have been calculated, respectively. Their physical origins have been revealed. It is found that the admixture of \t(2)(2)(T-3(1))e(4)T(2)) and \t(2)(32) E) base-wavefunctions in the wavefunctions of R-1 level of GSGG: Cr3+ at 70 K is remarkable under the normal pressure, and the degree of the admixture rapidly decreases with increasing pressure. The change of the degree of the admixture with the pressure plays a key role for not only the pure electronic PS of R-1 line but also the PS of R-1 line due to EPI. The detailed calculations and analyses show that the pressure-dependent behaviors of the pure electronic PS of R, line and the PS of R-1 line due to EPI are quite different. It is the combined effect of them that gives rise to the total PS of R, line, which has satisfactorily explained the experimental data (including a reversal of PS of R-1 line). In contributions to PS of R-1 line due to EPI at 70 K, the temperature-independent contribution is much larger than the temperature-dependent contribution. The former results from the interaction between the zero-point vibration of the lattice and localized electronic state.
关键词:
high-pressure effect;spin-orbit interaction;electron-phonon;interaction;d orbital;coupling between t(2)(2)(T-3(1))e(4)T(2) and;t(2)(3)(2)E;tunable laser crystal;temperature
刘欢
,
严凯
,
晏井利
,
薛烽
,
孙甲鹏
,
江静华
,
马爱斌
中国有色金属学报(英文版)
doi:10.1016/S1003-6326(17)60007-4
为了揭示14H相的形成机理，制备并研究了18R LPSO单相Mg?Y?Zn(简称S18)合金经773 K退火100 h的显微组织演变。结果表明：铸态S18合金主要由18R相组成(其体积分数高于93%)，并含有少量的W相和α-Mg相。退火时，S18合金中的18R相保持稳定，未转变成14H LPSO结构。然而，在α-Mg相内部形成了14H层片相，其尺寸和体积分数随着退火时间的延长不断增大。TEM分析表明，14H相在α-Mg内基面堆垛层错区域独立形核。14H层片的增厚生长是界面控制过程，与基面台阶的形成密切联系。而14H层片的伸长生长属于扩散控制，与溶质元素的扩散有关。该18R单相合金中14H相的形成机理可通过反应式α-Mg'→α-Mg +14H表示。
关键词:
Mg-Y-Zn合金
,
18R LPSO相
,
14H LPSO相
,
高温退火
,
显微组织演变
林婷惠
,
曹长林
,
陈庆华
,
钱庆荣
,
黄宝铨
,
夏新曙
,
林新土
,
肖荔人
材料工程
doi:10.11868/j.issn.1001-4381.2016.03.015
以回收聚四氟乙烯(r-PTFE)为成核剂,对聚对苯二甲酸丁二醇酯(BPT)进行成核结晶改性,采用差示扫描量热仪(DSC)研究了PBT/r-PTFE复合材料的非等温结晶行为,考察了不同降温速率对PBT/r-PTFE共混物结晶行为的影响,并对其DSC扫描数据采用Jeziorny法和Liu-Mo法进行处理,采用Kissiinger法计算体系结晶活化能.结果表明:r-PT-FE对PBT具有异相成核作用,可明显提高PBT的结晶度及其结晶速率,且加入r-PTFE并不会改变PBT的成核和增长方式.由Kissinger法计算得出的结晶活化能结果表明,加入r-PTFE树脂能够明显降低PBT的结晶活化能,进一步验证r-PTFE对PBT具有成核促进作用.
关键词:
聚对苯二甲酸丁二醇酯
,
回收聚四氟乙烯
,
非等温结晶动力学
,
活化能
Transactions of Nonferrous Metals Society of China
Phase equilibria of the R-Fe-Co pseudoternary system with R less than or equal to 33.3% ( mole fraction, R = Sm0.5Dy0.5) were determined in an isothermal section at 1073 K and a vertical section of RFe2-RCo2 by using OM, X-ray diffractometer, EP-MA DTA techniques. There are seven intermetallic phases: (Sm, Dy) (Fe, Co)(2), (Sm, Dy) (Fe, Co)(3), (Sm, Dy)(6) (Fe, Co)(23), (Sm, Dy)(2) (Fe, Co)(7), (Sm, Dy) (Fe, Co)(5), Th2Ni17-type and Th2Zn17-type (Sm, Dy)(2)(Fe, Co)(17). The (Sm, Dy)(6)(Fe, Co)(23) phase dissolves 36% Co(mole fraction) at 1073 K. However, the (Sm, Dy)(2)(Fe, Co)(7) phase in R-2(Fe1-xCox)(7) alloys dissolves about 19% Fe(mole fraction) at 1073 K.
关键词:
rare earth-iron-cobalt;phase diagram;structure;compounds;sm-co;magnetic-properties;binary-system;magnetostriction
Physical Review B
The spin-reorientation transition, magnetic anisotropy, and first-order magnetization process (FOMP) of R2Fe14BNx compounds with R = Pr or Nd have been investigated by ac-susceptibility measurements from 4.2 to 300 K, the singular-point-detection technique in a pulsed-field facility in fields up to 30 T between 4.2 and 500 K and magnetization measurements in the Amsterdam High-Field Installation in fields up to 35 T and 4.2 K. It is observed that, compared to the corresponding R2Fe14B compounds, the anisotropy field, B(a), and the critical field of the FOMP, B(cr), of R2Fe14BNx are dramatically reduced, whereas the spin-reorientation temperature T(SR), of Nd2Fe14BNx is only slightly decreased. These experimental data are analyzed in terms of the crystalline-electric-field interaction combined with the R-Fe exchange interaction.
关键词:
field magnetization measurements;single-crystals;nd2fe14b;transition;nitrides;pr2fe14b;series
