Energy levels, oscillator strengths, and transition probabilities, for the 1s2 2s2 2p6, 2p53l (l = 0, 1, 2), 2p54l (l = 0, 1, 2, 3) states in Ni XIX and Cu XX are calculated using COWAN code. The Correlation and relat...Energy levels, oscillator strengths, and transition probabilities, for the 1s2 2s2 2p6, 2p53l (l = 0, 1, 2), 2p54l (l = 0, 1, 2, 3) states in Ni XIX and Cu XX are calculated using COWAN code. The Correlation and relativistic effects are considered. The calculations are compared with other results in the literature. A good agreement is found. We also report on some unpublished energy values.展开更多
In this work numerical codes carried out in a multiconfiguration Har-tree-Fock relativistic (HFR) approach for the P IV ion are used to obtain the oscillator strengths of each transition as well as the lifetimes of ea...In this work numerical codes carried out in a multiconfiguration Har-tree-Fock relativistic (HFR) approach for the P IV ion are used to obtain the oscillator strengths of each transition as well as the lifetimes of each energy level. With the existing data from several authors that contributed to the spectrum using different light sources, and optimizing the electrostatic parameters by a least-squares procedure when replacing the theoretical values by the experimental ones in the energy matrices, one obtains closer values and according to the observations for the intensities, and also of the lifetimes closer to those that would be obtained experimentally.展开更多
The P XIII spectrum has been analyzed by several authors using different light sources. The semi-empirical oscillator strengths (gf) and the lifetimes presented in this work for all known P XIII spectral lines and ene...The P XIII spectrum has been analyzed by several authors using different light sources. The semi-empirical oscillator strengths (gf) and the lifetimes presented in this work for all known P XIII spectral lines and energy levels were carried out in a multi-configuration Hartree-Fock relativistic (HFR) approach. In this calculation, the electrostatic parameters were optimized by a least-squares procedure in order to improve the adjustment of theoretical to experimental energy levels. The method produces gf-values that are in agreement with intensity observations and lifetime values closer to the experimental ones.展开更多
This paper applies the stochastic finite element method to analyse the statistics of stresses in earth dams and assess the safety and reliability of the dams. Formulations of the stochastic finite element method are b...This paper applies the stochastic finite element method to analyse the statistics of stresses in earth dams and assess the safety and reliability of the dams. Formulations of the stochastic finite element method are briefly reviewed and the procedure for assessing dam's strength and stability is described. As an example, a detailed analysis for an actual dam Nululin dam is performed. A practical method for studying built-dams based on the prototype observation data is described.展开更多
鲁汶流是东印度洋海区低盐暖水向极传输的主要途径,不仅显著调节低纬-高纬海区间的温盐分配,也极大影响澳大利亚西岸降水,理解其在地质历史时期的变化及影响因素,对于认识区域和全球气候变化具有重要意义。本次研究将鲁汶流区采集的SO18...鲁汶流是东印度洋海区低盐暖水向极传输的主要途径,不仅显著调节低纬-高纬海区间的温盐分配,也极大影响澳大利亚西岸降水,理解其在地质历史时期的变化及影响因素,对于认识区域和全球气候变化具有重要意义。本次研究将鲁汶流区采集的SO18588孔岩芯上部63 cm沉积物作为研究材料,并以1 cm为间隔对其进行采样,共计获得63个沉积物样品。通过对这些沉积物样品进行研究,发现在SO18588站处浮游有孔虫热带表层水种Trilobatus sacculifer的相对丰度比浮游有孔虫热带-亚热带表层水种Globigerinoides ruber的相对丰度更适合被用于指示鲁汶流强度变化;之后,利用浮游有孔虫热带表层水种T.sacculifer的相对丰度,重建了32 ka B. P.以来鲁汶流的强度变化,并与已发表的古海洋和古气候学记录进行了对比。结果显示,鲁汶流强度的冰期-间冰期变化受海平面升降和类厄尔尼诺-南方涛动气候态共同调控:冰期时海平面下降,类厄尔尼诺态强化,导致鲁汶流减弱;间冰期时,海平面上升,类拉尼娜态发育,造成鲁汶流增强。9.5~0 ka B. P.期间,鲁汶流强度的持续弱化,可能归因于澳洲冬季风的减弱和早全新世类拉尼娜格局向现代类厄尔尼诺格局转变所造成的厄尔尼诺事件频发;9.5 ka B. P.左右鲁汶流强度事件性地突然减弱,可能与海平面上升所导致的卡里马塔海峡贯通、印尼穿越流表层流被抑制有关。展开更多
文摘Energy levels, oscillator strengths, and transition probabilities, for the 1s2 2s2 2p6, 2p53l (l = 0, 1, 2), 2p54l (l = 0, 1, 2, 3) states in Ni XIX and Cu XX are calculated using COWAN code. The Correlation and relativistic effects are considered. The calculations are compared with other results in the literature. A good agreement is found. We also report on some unpublished energy values.
文摘In this work numerical codes carried out in a multiconfiguration Har-tree-Fock relativistic (HFR) approach for the P IV ion are used to obtain the oscillator strengths of each transition as well as the lifetimes of each energy level. With the existing data from several authors that contributed to the spectrum using different light sources, and optimizing the electrostatic parameters by a least-squares procedure when replacing the theoretical values by the experimental ones in the energy matrices, one obtains closer values and according to the observations for the intensities, and also of the lifetimes closer to those that would be obtained experimentally.
文摘The P XIII spectrum has been analyzed by several authors using different light sources. The semi-empirical oscillator strengths (gf) and the lifetimes presented in this work for all known P XIII spectral lines and energy levels were carried out in a multi-configuration Hartree-Fock relativistic (HFR) approach. In this calculation, the electrostatic parameters were optimized by a least-squares procedure in order to improve the adjustment of theoretical to experimental energy levels. The method produces gf-values that are in agreement with intensity observations and lifetime values closer to the experimental ones.
文摘This paper applies the stochastic finite element method to analyse the statistics of stresses in earth dams and assess the safety and reliability of the dams. Formulations of the stochastic finite element method are briefly reviewed and the procedure for assessing dam's strength and stability is described. As an example, a detailed analysis for an actual dam Nululin dam is performed. A practical method for studying built-dams based on the prototype observation data is described.
文摘鲁汶流是东印度洋海区低盐暖水向极传输的主要途径,不仅显著调节低纬-高纬海区间的温盐分配,也极大影响澳大利亚西岸降水,理解其在地质历史时期的变化及影响因素,对于认识区域和全球气候变化具有重要意义。本次研究将鲁汶流区采集的SO18588孔岩芯上部63 cm沉积物作为研究材料,并以1 cm为间隔对其进行采样,共计获得63个沉积物样品。通过对这些沉积物样品进行研究,发现在SO18588站处浮游有孔虫热带表层水种Trilobatus sacculifer的相对丰度比浮游有孔虫热带-亚热带表层水种Globigerinoides ruber的相对丰度更适合被用于指示鲁汶流强度变化;之后,利用浮游有孔虫热带表层水种T.sacculifer的相对丰度,重建了32 ka B. P.以来鲁汶流的强度变化,并与已发表的古海洋和古气候学记录进行了对比。结果显示,鲁汶流强度的冰期-间冰期变化受海平面升降和类厄尔尼诺-南方涛动气候态共同调控:冰期时海平面下降,类厄尔尼诺态强化,导致鲁汶流减弱;间冰期时,海平面上升,类拉尼娜态发育,造成鲁汶流增强。9.5~0 ka B. P.期间,鲁汶流强度的持续弱化,可能归因于澳洲冬季风的减弱和早全新世类拉尼娜格局向现代类厄尔尼诺格局转变所造成的厄尔尼诺事件频发;9.5 ka B. P.左右鲁汶流强度事件性地突然减弱,可能与海平面上升所导致的卡里马塔海峡贯通、印尼穿越流表层流被抑制有关。
