Context.
In solar physics, a severe numerical challenge for modern simulations is properly representing a transition region between the million-degree hot corona and a much cooler plasma of about 10 ...000 K (e.g., the upper chromosphere or a prominence). In previous 1D hydrodynamic simulations, the transition region adaptive conduction (TRAC) method has been proven to capture aspects better that are related to mass evaporation and energy exchange.
Aims.
We aim to extend this method to fully multidimensional magnetohydrodynamic (MHD) settings, as required for any realistic application in the solar atmosphere. Because modern MHD simulation tools efficiently exploit parallel supercomputers and can handle automated grid refinement, we design strategies for any-dimensional block grid-adaptive MHD simulations.
Methods.
We propose two different strategies and demonstrate their working with our open-source
MPI-AMRVAC
code. We benchmark both strategies on 2D prominence formation based on the evaporation–condensation scenario, where chromospheric plasma is evaporated through the transition region and then is collected and ultimately condenses in the corona.
Results.
A field-line-based TRACL method and a block-based TRACB method are introduced and compared in block grid-adaptive 2D MHD simulations. Both methods yield similar results and are shown to satisfactorily correct the underestimated chromospheric evaporation, which comes from a poor spatial resolution in the transition region.
Conclusions.
Because fully resolving the transition region in multidimensional MHD settings is virtually impossible, TRACB or TRACL methods will be needed in any 2D or 3D simulations involving transition region physics.
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•Environmental impacts and benefits of twelve current sludge treatment and disposal routes in China are evaluated.•Co-incineration has the negative toxicity impacts and carbon ...emissions due to the offset of energy recovery.•Carbon emissions of co-incineration, anaerobic digestion, and anaerobic digestion with thermal hydrolysis are −27.26, −572.44, and −474.92 kg CO2 eq/t DS, respectively.•Controlling heavy metals is the priority of digested sludge land application.
The management and utilization of sludge in a sustainable approach require a systematic analysis of the environmental impacts generated from diverse sludge treatment and disposal processes. This study systematically assessed 12 common sludge treatment and disposal routes based on the existing operating and construction conditions of representative sludge disposal projects in China. We evaluated their environmental impacts using a life cycle assessment following the International Organization for Standardization (ISO 14040 and ISO 14044), and found that the routes of co-incineration, mono-incineration, and anaerobic digestion with or without thermal hydrolysis may be useful in terms of simultaneously controlling environmental pollution and carbon emissions in China. Therein, the route of co-incineration was recommended as the best one because its human toxicity potential (−152.31 kg dichlorobenzene (1,4-DB) eq/ton dry solid (t DS)), freshwater ecotoxicity potential (FEP, −127.40 kg 1,4-DB eq/t DS), terrestrial ecotoxicity potential (TEP, −0.81 kg 1,4-DB eq/t DS), and global warming potential (−27.26 kg CO2 eq/t DS) were all negative (environmental benefits). Furthermore, the toxicity impacts of the mono-incineration route were also negative, but it still needed to further enhance energy recovery to reduce carbon emissions. Despite the routes of anaerobic digestion and thermal hydrolysis in combination with anaerobic digestion had the excellent negative carbon emission attributes (-572.44 kg CO2 eq/t DS, −474.92 kg CO2 eq/t DS), they showed serious FEP and TEP owing to the heavy metals pollution caused by subsequent land use of anaerobic digested sludge. Overall, this study selected the most suitable sludge treatment and disposal routes to simultaneously satisfy the requirements of carbon emission reduction and pollution control in China and proposed optimizing suggestions for future technical improvement and development.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Impaired cardiac microvascular function contributes to diabetic cardiovascular complications although effective therapy remains elusive. Empagliflozin, a sodium-glucose cotransporter 2 (SGLT2) ...inhibitor recently approved for treatment of type 2 diabetes, promotes glycosuria excretion and offers cardioprotective actions beyond its glucose-lowering effects. This study was designed to evaluate the effect of empagliflozin on cardiac microvascular injury in diabetes and the underlying mechanism involved with a focus on mitochondria. Our data revealed that empagliflozin improved diabetic myocardial structure and function, preserved cardiac microvascular barrier function and integrity, sustained eNOS phosphorylation and endothelium-dependent relaxation, as well as improved microvessel density and perfusion. Further study suggested that empagliflozin exerted its effects through inhibition of mitochondrial fission in an adenosine monophosphate (AMP)-activated protein kinase (AMPK)-dependent manner. Empagliflozin restored AMP-to-ATP ratio to trigger AMPK activation, suppressed Drp1S616 phosphorylation, and increased Drp1S637 phosphorylation, ultimately leading to inhibition of mitochondrial fission. The empagliflozin-induced inhibition of mitochondrial fission preserved cardiac microvascular endothelial cell (CMEC) barrier function through suppressed mitochondrial reactive oxygen species (mtROS) production and subsequently oxidative stress to impede CMEC senescence. Empagliflozin-induced fission loss also favored angiogenesis by promoting CMEC migration through amelioration of F-actin depolymerization. Taken together, these results indicated the therapeutic promises of empagliflozin in the treatment of pathological microvascular changes in diabetes.
•Empagliflozin alleviates diabetes-induced cardiac microvascular dysfunction.•Hyperglycemia triggers CMEC dysfunction via mitochondrial fission.•Empagliflozin inhibits fission and delays CMEC senescence via suppressing mtROS oxidative stress.•Empagliflozin facilitates CMEC migration and neovascularization by preservation of F-actin homeostasis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The combined effect of polystyrene microplastics (mPS) and dibutyl phthalate (DBP), a common plastic additive, on the microalgae Chlorella pyrenoidosa was investigated in the present study. The 96 ...h-IC50 value of DBP was 2.41 mg L−1. Polystyrene microplastics exhibited size-dependent inhibitory effect to C. pyrenoidosa, with the 96 h-IC50 at 6.90 and 7.19 mg L−1 for 0.1 and 0.55 μm mPS respectively, but little toxicity was observed for 5 μm mPS. The interaction parameter ρ based on the response additive response surface (RARS) model varied from −0.309 to 5.845, indicating the interaction pattern varying with exposure concentrations of chemical mixtures. A modified RARS model (taking ρ as a function of exposure concentration) was constructed and could well predict the combined toxicity of mPS and DBP. More than 20% reduction of DBP was observed at 20 mg L−1 mPS, while 1 mg L−1 mPS had no significant effect on the bioavailability of DBP at different sampling time points. Volume, morphological complexity and chlorophyll fluorescence intensity of microalgal cells were disturbed by both DBP and mPS. The antagonistic effect of high concentrations of mPS might be partially attributed to the combination of hetero- and homo-aggregation and the reduced bioavailability of DBP. The overall findings of the present study profiled the combined toxic effects of mPS and DBP on marine phytoplankton species which will be helpful for further evaluation of ecological risks of mPS and DBP in marine environment.
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•The interaction parameter of RARS model varied with the concentration of mPS-DBP.•The combined effect of mPS and DBP was variable at different concentration ranges.•mPS could reduce the bioavailability of DBP.•C. pyrenoidosa formed hetero- and homo-aggregates with mPS.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Emotional exhaustion in the workplace can cause employees psychological and physical health problems, affect work performance, and create burdens for the organization. Existing studies have ...demonstrated that psychological empowerment helps reduce emotional exhaustion. This study explores the internal mechanism of this relationship. Drawing on conservation of resources theory, we advance a dual mediation model to explain how high psychological empowerment results in low emotional exhaustion, by increasing psychological safety and organizational embeddedness. Data were collected from 226 on-the-job MBA students at a university in western China. The results demonstrate that psychological safety and organizational embeddedness play mediating roles in the negative relationship between psychological empowerment and emotional exhaustion. The study provides a systematic view of the negative effect that psychological empowerment has on emotional exhaustion. The paper also discusses theoretical contributions, practical implications, and future directions.
Soft porous coordination polymers (PCPs) have the remarkable ability to recognize similar molecules as a result of their structural dynamics. However, their guest‐induced gate‐opening behaviors often ...lead to issues with selectivity and separation efficiency, as co‐adsorption is nearly unavoidable. Herein, we report a strategy of a confined‐rotational shutter, in which the rotation of pyridyl rings within the confined nanospace of a halogen‐bonded coordination framework (NTU‐88) creates a maximum aperture of 4.4 Å, which is very close to the molecular size of propyne (C3H4: 4.4 Å), but smaller than that of propylene (C3H6: 5.4 Å). This has been evidenced by crystallographic analyses and modelling calculations. The NTU‐88o (open phase of activated NTU‐88) demonstrates dedicated C3H4 adsorption, and thereby leads to a sieving separation of C3H4/C3H6 under ambient conditions. The integrated nature of high uptake ratio, considerable capacity, scalable synthesis, and good stability make NTU‐88 a promising candidate for the feasible removal of C3H4 from C3H4/C3H6 mixtures. In principle, this strategy holds high potential for extension to soft families, making it a powerful tool for optimizing materials that can tackle challenging separations with no co‐adsorption, while retaining the crucial aspect of high capacity.
A soft nanoporous crystal has been developed that can separate propyne/propylene mixtures by sieving. This occurs by the rotational movement of pyridyl rings within this framework creating a pore with a maximum size of 4.4 Å, thereby facilitating the adsorption of propyne while completely excluding propylene.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The slow redox kinetics of polysulfides and the difficulties in decomposition of Li
S during the charge and discharge processes are two serious obstacles to the practical application of ...lithium-sulfur batteries. Herein, we construct the Fe-Co diatomic catalytic materials supported by hollow carbon spheres to achieve high-efficiency catalysis for the conversion of polysulfides and the decomposition of Li
S simultaneously. The Fe atom center is beneficial to accelerate the discharge reaction process, and the Co atom center is favorable for charging process. Theoretical calculations combined with experiments reveal that this excellent bifunctional catalytic activity originates from the diatomic synergy between Fe and Co atom. As a result, the assembled cells exhibit the high rate performance (the discharge specific capacity achieves 688 mAh g
at 5 C) and the excellent cycle stability (the capacity decay rate is 0.018% for 1000 cycles at 1 C).
An intelligent human–machine interface (HMI) is a crucial medium for exchanging information between people and electronics. As one of the most important HMI devices, touch screen sensors are widely ...applied in personal electronics in daily life. However, as the most commonly used touch screen sensor, capacitive sensors can only detect limited kinds of gestures such as touching and sliding. Here, a triboelectric touch‐free screen sensor (TSS) is reported for recognizing diverse gestures in a noncontact operating mode by utilizing the charges naturally carried on the human body. Compared with conventional capacitive sensors, the TSS is capable of detecting various gestures such as the drop and lift of finger with different speeds, making a fist, opening palm, and flipping palm with different directions. Based on the TSS, an intelligent noncontact screen control system is further developed, which is used to unlock the smartphone interface by the noncontact operating mode. This research for the first time proposes the concept that taking the human body itself to participate in triboelectric self‐powered noncontact sensing and provides a touch‐free design concept to develop the next generation of screen sensors. It can alter the usual way that people operating their personal electronics.
A triboelectric touch‐free screen sensor (TSS) for recognizing diverse gestures is successfully demonstrated. Based on the TSS, an intelligent noncontact screen control system is further developed, which realizes the unlocking of a smartphone interface via the noncontact operating mode. This TSS with the noncontact gesture sensing method could make a remarkable breakthrough in establishing intelligent human–machine interactions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The lithium storage properties of graphene nanosheet (GNS) materials as high capacity anode materials for rechargeable lithium secondary batteries (LIB) were investigated. Graphite is a practical ...anode material used for LIB, because of its capability for reversible lithium ion intercalation in the layered crystals, and the structural similarities of GNS to graphite may provide another type of intercalation anode compound. While the accommodation of lithium in these layered compounds is influenced by the layer spacing between the graphene nanosheets, control of the intergraphene sheet distance through interacting molecules such as carbon nanotubes (CNT) or fullerenes (C60) might be crucial for enhancement of the storage capacity. The specific capacity of GNS was found to be 540 mAh/g, which is much larger than that of graphite, and this was increased up to 730 mAh/g and 784 mAh/g, respectively, by the incorporation of macromolecules of CNT and C60 to the GNS.
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