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 o...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<SUB>1</SUB> line, R<SUB>2</SUB> line, and U band of GSGG:Cr<SUP>3+</SUP> 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-degree of and base-wavefunctions in the wavefunctions of R<SUB>1</SUB> level of GSGG:Cr<SUP>3+</SUP> 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<SUB>1</SUB> line and R<SUB>2</SUB> line but also the PS of R<SUB>1</SUB> line and R<SUB>2</SUB> line due to EPI. The pressure-dependent behaviors of the 'pure electronic' PS of R<SUB>1</SUB> line (or R<SUB>2</SUB> line) and the PS of R<SUB>1</SUB> line (or R<SUB>2</SUB> line) due to EPI are quite different. It is the combined effect of them that gives rise to the total PS of R<SUB>1</SUB> line (or R<SUB>2</SUB> line). In the range of about 15 kbar ~ 45 kbar, the mergence and/or order-reversal between levels and levels take place, which cause the fluctuation of the rate of PS for with pressure. At 300 K, both the temperature-dependent contribution to R<SUB>1</SUB> line (or R<SUB>2</SUB> line or U band) from EPI and the temperature-independent one are important.展开更多
目的探讨苯并[a]芘(benzo[a]pyrene,B[a]P)宫内暴露与胚胎停育的关联,以及辅助性T细胞1/辅助性T细胞2(helper T cell 1/helper T cell 2,Th1/Th2)平衡偏移的中介效应。方法选取胚胎停育患者与正常妊娠但自愿人工流产的女性作为研究对象(...目的探讨苯并[a]芘(benzo[a]pyrene,B[a]P)宫内暴露与胚胎停育的关联,以及辅助性T细胞1/辅助性T细胞2(helper T cell 1/helper T cell 2,Th1/Th2)平衡偏移的中介效应。方法选取胚胎停育患者与正常妊娠但自愿人工流产的女性作为研究对象(245名)。检测研究对象绒毛组织中7,8-二羟-9,10-环氧苯并[a]芘(7,8-dihydroxy-9,10-epoxy-benzo[a]pyrene,BPDE)-DNA加合物与白细胞介素(interleukin,IL)-2、干扰素-γ(interferon-γ,IFN-γ)、IL-4、IL-10水平。采用logistic回归分析模型分析B[a]P暴露与胚胎停育的关联,运用Bootstrap法分析Th1/Th2平衡偏移的中介效应。结果调整协变量后,BPDE-DNA加合物的中高暴露、高暴露水平发生胚胎停育的风险分别是低暴露水平的5.66倍(aOR=5.66,95%CI:2.00~16.01,P<0.001)、5.63倍(aOR=5.63,95%CI:1.97~16.14,P<0.001);中介分析结果显示,B[a]P对胚胎停育的总效应为1.220(0.501~1.939),Th1/Th2平衡偏移介导的中介效应为0.328(0.078~0.716),中介比例占26.89%。结论B[a]P暴露是胚胎停育的危险因素,且Th1/Th2失衡发生Th1型偏移是B[a]P暴露致胚胎停育的中介变量。展开更多
A theory for shifts of energy spectra due to electron-phonon interaction (EPI) has been developed. Both the temperature-independent contributions and the temperature-dependent ones of acoustic branches and optical bra...A theory for shifts of energy spectra due to electron-phonon interaction (EPI) has been developed. Both the temperature-independent contributions and the temperature-dependent ones of acoustic branches and optical branches have been derived. It is found that the temperature-independent contributions are very important, especially at low temperature. The total pressure-induced shift (PS) of a level (or spectral line or band) is the algebraic sum of its PS without EPI and its PS due to EPI. By means of both the theory for shifts of energy spectra due to EPI and the theory for PS of energy spectra, the total PS of R<SUB>1</SUB> line of tunable laser crystal GSGG:Cr<SUP>3+</SUP> at 70 K as well as the ones of its R<SUB>1</SUB> line, R<SUB>2</SUB> line and U band at 300 K will be successfully calculated and explained in this series of papers.展开更多
By means of improved ligand-field theory, the ＂pure electronic＂ pressure-induced shift （PS） and the PS due to electron-phonon interaction （EPI） of R-line of MgO：Cr^3＋ have been calculated, respectively. The ca...By means of improved ligand-field theory, the ＂pure electronic＂ pressure-induced shift （PS） and the PS due to electron-phonon interaction （EPI） of R-line of MgO：Cr^3＋ have been calculated, respectively. The calculated results are in very good agreement with the experimental data. The behaviors of the pure electronic PS of R-line of MgO：Cr^3＋ and the PS of its R-line due to EPI are different. It is the combined effect of them that gives rise to the total PS of R-line, which has satisfactorily explained the experimental results. The comparison between the feature of R-line PS of MgO：Cr^3＋ and that of R1-line PS of ruby has been made.展开更多
By means of an improved ligand-field theory, the ＂pure electronic＂ PS and the PS due to EPI of R line of MgO： V^2＋ have been calculated, respectively. The calculated results are in very good agreement with the exp...By means of an improved ligand-field theory, the ＂pure electronic＂ PS and the PS due to EPI of R line of MgO： V^2＋ have been calculated, respectively. The calculated results are in very good agreement with the experimental data. The behaviors of the pure electronic PS of R line of MgO：V^2＋ and the PS of its R line due to EPI are different. It is the combined effect of them that gives rise to the total PS of R line, which has satisfactorily explained the experimental results. The mixing-degree of ｜t2^2（^3T1）e^4T2〉 and ｜t2^3 ^2E〉 in the wavefunetion of R level and its variation with pressure have been calculated and analyzed. The comparison between the feature of R-line PS of MgO：V^2＋ and that of MgO：Cr^3＋ has been made.展开更多
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 o...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<SUB>1</SUB> line of GSGG:Cr<SUP>3+</SUP> at 70 K have been calculated, respectively. Their physical origins have been revealed. It is found that the admixture of and base-wavefunctions in the wavefunctions of R<SUB>1</SUB> level of GSGG:Cr<SUP>3+</SUP> 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<SUB>1</SUB> line but also the PS of R<SUB>1</SUB> line due to EPI. The detailed calculations and analyses show that the pressure-dependent behaviors of the pure electronic PS of R<SUB>1</SUB> line and the PS of R<SUB>1</SUB> line due to EPI are quite different. It is the combined effect of them that gives rise to the total PS of R<SUB>1</SUB> line, which has satisfactorily explained the experimental data (including a reversal of PS of R<SUB>1</SUB> line). In contributions to PS of R<SUB>1</SUB> 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.展开更多
文摘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<SUB>1</SUB> line, R<SUB>2</SUB> line, and U band of GSGG:Cr<SUP>3+</SUP> 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-degree of and base-wavefunctions in the wavefunctions of R<SUB>1</SUB> level of GSGG:Cr<SUP>3+</SUP> 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<SUB>1</SUB> line and R<SUB>2</SUB> line but also the PS of R<SUB>1</SUB> line and R<SUB>2</SUB> line due to EPI. The pressure-dependent behaviors of the 'pure electronic' PS of R<SUB>1</SUB> line (or R<SUB>2</SUB> line) and the PS of R<SUB>1</SUB> line (or R<SUB>2</SUB> line) due to EPI are quite different. It is the combined effect of them that gives rise to the total PS of R<SUB>1</SUB> line (or R<SUB>2</SUB> line). In the range of about 15 kbar ~ 45 kbar, the mergence and/or order-reversal between levels and levels take place, which cause the fluctuation of the rate of PS for with pressure. At 300 K, both the temperature-dependent contribution to R<SUB>1</SUB> line (or R<SUB>2</SUB> line or U band) from EPI and the temperature-independent one are important.
文摘目的探讨苯并[a]芘(benzo[a]pyrene,B[a]P)宫内暴露与胚胎停育的关联,以及辅助性T细胞1/辅助性T细胞2(helper T cell 1/helper T cell 2,Th1/Th2)平衡偏移的中介效应。方法选取胚胎停育患者与正常妊娠但自愿人工流产的女性作为研究对象(245名)。检测研究对象绒毛组织中7,8-二羟-9,10-环氧苯并[a]芘(7,8-dihydroxy-9,10-epoxy-benzo[a]pyrene,BPDE)-DNA加合物与白细胞介素(interleukin,IL)-2、干扰素-γ(interferon-γ,IFN-γ)、IL-4、IL-10水平。采用logistic回归分析模型分析B[a]P暴露与胚胎停育的关联,运用Bootstrap法分析Th1/Th2平衡偏移的中介效应。结果调整协变量后,BPDE-DNA加合物的中高暴露、高暴露水平发生胚胎停育的风险分别是低暴露水平的5.66倍(aOR=5.66,95%CI:2.00~16.01,P<0.001)、5.63倍(aOR=5.63,95%CI:1.97~16.14,P<0.001);中介分析结果显示,B[a]P对胚胎停育的总效应为1.220(0.501~1.939),Th1/Th2平衡偏移介导的中介效应为0.328(0.078~0.716),中介比例占26.89%。结论B[a]P暴露是胚胎停育的危险因素,且Th1/Th2失衡发生Th1型偏移是B[a]P暴露致胚胎停育的中介变量。
文摘A theory for shifts of energy spectra due to electron-phonon interaction (EPI) has been developed. Both the temperature-independent contributions and the temperature-dependent ones of acoustic branches and optical branches have been derived. It is found that the temperature-independent contributions are very important, especially at low temperature. The total pressure-induced shift (PS) of a level (or spectral line or band) is the algebraic sum of its PS without EPI and its PS due to EPI. By means of both the theory for shifts of energy spectra due to EPI and the theory for PS of energy spectra, the total PS of R<SUB>1</SUB> line of tunable laser crystal GSGG:Cr<SUP>3+</SUP> at 70 K as well as the ones of its R<SUB>1</SUB> line, R<SUB>2</SUB> line and U band at 300 K will be successfully calculated and explained in this series of papers.
文摘By means of improved ligand-field theory, the ＂pure electronic＂ pressure-induced shift （PS） and the PS due to electron-phonon interaction （EPI） of R-line of MgO：Cr^3＋ have been calculated, respectively. The calculated results are in very good agreement with the experimental data. The behaviors of the pure electronic PS of R-line of MgO：Cr^3＋ and the PS of its R-line due to EPI are different. It is the combined effect of them that gives rise to the total PS of R-line, which has satisfactorily explained the experimental results. The comparison between the feature of R-line PS of MgO：Cr^3＋ and that of R1-line PS of ruby has been made.
文摘By means of an improved ligand-field theory, the ＂pure electronic＂ PS and the PS due to EPI of R line of MgO： V^2＋ have been calculated, respectively. The calculated results are in very good agreement with the experimental data. The behaviors of the pure electronic PS of R line of MgO：V^2＋ and the PS of its R line due to EPI are different. It is the combined effect of them that gives rise to the total PS of R line, which has satisfactorily explained the experimental results. The mixing-degree of ｜t2^2（^3T1）e^4T2〉 and ｜t2^3 ^2E〉 in the wavefunetion of R level and its variation with pressure have been calculated and analyzed. The comparison between the feature of R-line PS of MgO：V^2＋ and that of MgO：Cr^3＋ has been made.
文摘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<SUB>1</SUB> line of GSGG:Cr<SUP>3+</SUP> at 70 K have been calculated, respectively. Their physical origins have been revealed. It is found that the admixture of and base-wavefunctions in the wavefunctions of R<SUB>1</SUB> level of GSGG:Cr<SUP>3+</SUP> 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<SUB>1</SUB> line but also the PS of R<SUB>1</SUB> line due to EPI. The detailed calculations and analyses show that the pressure-dependent behaviors of the pure electronic PS of R<SUB>1</SUB> line and the PS of R<SUB>1</SUB> line due to EPI are quite different. It is the combined effect of them that gives rise to the total PS of R<SUB>1</SUB> line, which has satisfactorily explained the experimental data (including a reversal of PS of R<SUB>1</SUB> line). In contributions to PS of R<SUB>1</SUB> 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.
