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As the dimensions of interconnects in integrated circuits continue to shrink, an urgent need arises to understand the physical mechanism associated with electromigration. Using x-ray nanodiffraction, we analyzed the stresses in Blech-structured pure Cu lines subjected to different electromigration conditions. The results suggest that the measured residual stresses in the early stages of electromigration are related to relaxation of stresses caused by thermal expansion mismatch, while a developing current-induced stress leads to reductions in the residual stress after longer test times. These findings not only validate the feasibility of measuring stress in copper lines using nanodiffraction but also highlight the need for a further understanding, particularly through in situ electromigration experiments with x-ray nanodiffraction analysis. [ABSTRACT FROM AUTHOR]

As one of the leading technologies for chemical enhanced oil recovery (cEOR), surfactant–polymer (SP) flooding technology has long attracted the interest of petroleum scientists and engineers. However, most of its application scenarios are based on the five-spot well pattern. The EOR potential in an inverted seven-spot well pattern is seldom ever recorded. The applicability of the SP system in the inverted seven-spot well pattern was examined based on the physical characteristics of Karamay Oilfield in China. The numerical simulation and the one-dimensional core flooding experiment were used to compare the sweep intensities and EOR abilities of the two well patterns. The migration law and the EOR ability of the SP system were assessed by a specially made one-third inverted seven-spot configuration. The main controlling factors and compatibility charts of SP flooding development in the inverted seven-spot well pattern were obtained. Results show that 61% of the region is represented by a weak swept state in the inverted seven-spot well pattern. The effective swept area is greatly increased by appropriately raising the viscosity and slug size of the SP system. Compared to constant viscosity injection, step-down viscosity injection further increases the sweep range and oil recovery. The inverted seven-spot well pattern has a greater swept area of the SP system than the five-spot one, but a weaker strength. Polymer concentration is the most effective factor of SP flooding in the inverted seven-spot well pattern, followed by oil viscosity and surfactant concentration. The study can broaden the application of the SP system in the inverted seven-spot well pattern. [ABSTRACT FROM AUTHOR]

At present, fluorescent glass mainly emits a single yellow light. The characteristic of green and red luminescent materials limits its omni-directional combination with yellow light materials, resulting in high correlated color temperature and low color rendering index of laser lighting devices, which seriously reduces the quality of laser lighting. Therefore, the development of multi-color fluorescent glass to improve the color quality is a huge challenge in laser lighting technology. In this research, the glass matrix that can be compounded with multi-color phosphors is proposed to solve the problems of phosphor decomposition, oxidation, corrosion, and blackening during the vitrification process. Surprisingly, a 50 wt. % Ce:YAG&1.5 wt. % CaAlSiN3-PiG (50 Y&1.5 R-PiG) sample exhibits an excellent internal quantum efficiency of 94% and achieves a high luminous efficiency of 184 lm/W under laser irradiation. Moreover, an ultrahigh luminous efficiency of 331 lm/W is realized by using a laser device with a heat sink. It demonstrated that Y&R-PiG can own excellent application prospects in high-quality lighting fields, such as laser displays and automobile headlights. [ABSTRACT FROM AUTHOR]

All inorganic remote Ce3+:Y3Al3.5Ga1.5O12 (Ce:YAGG) phosphor-in-glass (PIG) is considered to be an ideal robust green-emitting light converter for high-quality laser diode applications. Herein, the preparation of Ce:YAGG PIGs using an economical solid state reaction is reported. The sintered composite materials have the advantages of yielding a high transparency of 53% in the visible region and a high internal quantum efficiency of 92.7%. Benefiting from remarkably superior thermal properties, a high thermal conductivity of 1.712 W m−1 K−1 and a high thermal stability that the luminescence intensity could maintain 91.6% at 503 K, and the PIG can withstand 3.49 W/mm2 blue laser radiation. When pumped by blue laser diodes and by controlling the phosphor content and a thickness of samples, the robust PIG materials produce green light with a luminous flux of 555.6 lm and a stable luminous efficiency of 254.5 lm/W as the blue laser density increasing up to 2.78 W/mm2. The above outstanding performance of Ce:YAGG PIGs indicates a strong perspective for future lighting source. [ABSTRACT FROM AUTHOR]