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AbstractThe performance of recuperative printed circuit heat exchangers is critical in supercritical CO2 (sCO2) power generation applications. This article presents a three-dimensional numerical model of sCO2 flowing in a printed circuit heat exchanger and investigates its thermohydraulic performance under different operation conditions. The simulations employ the standard k-ε turbulent model, and consider entrance effects, conjugate heat transfer, real gas thermophysical properties and buoyancy effects. The heat exchanger operation parameters cover mass flux from 254.6 to 1273.2 kg/m2s, inlet temperature 50–150 °C and outlet pressure 100–250 bar on the cold side, and 300–500 °C and 75–150 bar on the hot side. Results show that increasing CO2 mass flux leads to a significantly increased heat transfer coefficient, a slight increase in temperature difference between the hot and cold CO2, as well as larger pressure drop and lower friction factor on both sides. Increasing the cold CO2 pressure, decreasing the cold CO2 temperature, and increasing the hot CO2 temperature result in a higher heat transfer rate of the heat exchanger. Increasing the CO2 temperature on each side causes increased pressure drops on both sides. Increasing the CO2 pressure on each side reduces the pressure drop on each side. [ABSTRACT FROM AUTHOR]

Lithium metal, with ultrahigh theoretical specific capacity, is considered as an ideal anode material for the lithium‐ion batteries. However, its practical application is severely plagued by the uncontrolled formation of dendritic Li. Here, a cation‐loaded porous Mg2+‐Zeolite layer is proposed to enable the dendrite‐free deposition on the surface of Li metal anode. The skeleton channels of zeolite provide the low coordinated Li+‐solvation groups, leading to the faster desolvation process at the interface. Meanwhile, anions‐involved solvation sheath induces a stable, inorganic‐rich SEI, contributing to the uniform Li+ flux through the interface. Furthermore, the co‐deposition of sustained release Mg2+ realizes a new faster migration pathway, which proactively facilitates the uniform diffusion of Li on the lithium substrate. The synergistic modulation of these kinetic processes facilitates the homogeneous Li plating/stripping behavior. Based on this synergistic mechanism, the high‐efficiency deposition with cyclic longevity exceeding 2100 h is observed in the symmetric Li/Li cell with Mg2+‐Zeolite modified anode at 1 mA cm−2. The pouch cell matched with LiFePO4 cathode fulfills a capacity retention of 88.4% after 100 cycles at a severe current density of 1 C charge/discharge. This synergistic protective mechanism can give new guidance for realizing the safe and high‐performance Li metal batteries. [ABSTRACT FROM AUTHOR]

This study examined the moderating role of perceived community belonging in the relationship between childhood abuse and health and well-being outcomes among Canadian individuals aged 55 and older. Using data from the 2014 Canadian General Social Survey (n = 14,416), multiple linear regression models revealed that women who experienced either childhood physical or sexual abuse reported poorer self-rated general and mental health, as well as lower life satisfaction, compared to those without such histories. The most pronounced effects were observed among women who experienced both types of abuse. For men, a similar pattern was evident only for those who experienced childhood physical abuse. Notably, among women, a strong sense of community belonging lessened the negative effects of both types of childhood abuse on all examined outcomes. These findings underscore the protective role of perceived community belonging against the consequences of childhood abuse for older women. They illuminate the crucial role of gerontological social workers and scholars in promoting community integration and support. Focusing on these areas, especially for those with traumatic histories, can potentially improve their overall health and well-being. [ABSTRACT FROM AUTHOR]

The present study asks: Is disability associated with suicidal ideation among Indigenous adults in Canada? And if so, do cultural resources—as measured by cultural identity affect, cultural group belonging, cultural engagement, and cultural exploration—modify this association? Data were from a nationally representative sample of First Nations peoples living off-reserve, Métis, and Inuit across Canada—the 2017 Aboriginal Peoples Survey (N = 16,125). A series of weighted logistic regression models were performed. Indigenous adults with disabilities were significantly more likely than those without disabilities to report suicidal ideation, even after controlling for socio-demographic characteristics and physical and mental health conditions. At the same time, people with multiple disabilities were at greater risk for suicidal ideation, with the largest association among those with five or more disabilities. Furthermore, the detrimental association between disability status and suicidal ideation attenuated among those who reported cultural group belonging. In a similar vein, the buffering role of cultural group belonging was also observed in the association between the number of disabilities and suicidal ideation. This study provides compelling evidence that disability is a risk factor for suicidal ideation among Indigenous adults and that cultural group belonging plays a stress-buffering role in this relationship. [ABSTRACT FROM AUTHOR]