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Eastern China has experienced severe and persistent winter haze episodes in recent years due to intensification of aerosol pollution. In addition to anthropogenic emissions, the winter aerosol pollution over eastern China is associated with unusual meteorological conditions, including weaker wind speeds. Here we show, based on model simulations, that during years with decreased wind speed, large decreases in dust emissions (29%) moderate the wintertime land-sea surface air temperature difference and further decrease winds by -0.06 (±0.05) m s-1 averaged over eastern China. The dust-induced lower winds enhance stagnation of air and account for about 13% of increasing aerosol concentrations over eastern China. Although recent increases in anthropogenic emissions are the main factor causing haze over eastern China, we conclude that natural emissions also exert a significant influence on the increases in wintertime aerosol concentrations, with important implications that need to be taken into account by air quality studies.

We report the study of Mg cathodic electrochemical deposition on Ti and Au electrode using a multimodal approach by examining the sample area in-situ using liquid cell transmission electron microscopy (TEM), scanning transmission X-ray microscopy (STXM) and X-ray absorption spectroscopy (XAS). Magnesium Aluminum Chloride Complex was synthesized and utilized as electrolyte, where non-reversible features during in situ charging-discharging cycles were observed. During charging, a uniform Mg film was deposited on the electrode, which is consistent with the intrinsic non-dendritic nature of Mg deposition in Mg ion batteries. The Mg thin film was not dissolvable during the following discharge process. We found that such Mg thin film is hexacoordinated Mg compounds by in-situ STXM and XAS. This study provides insights on the non-reversibility issue and failure mechanism of Mg ion batteries. Also, our method provides a novel generic method to understand the in situ battery chemistry without any further sample processing, which can preserve the original nature of battery materials or electrodeposited materials. This multimodal in situ imaging and spectroscopy provides many opportunities to attack complex problems that span orders of magnitude in length and time scale, which can be applied to a broad range of the energy storage systems.

Nanoparticle self-assembly has been well studied theoretically, but it remains challenging to directly observe and quantify individual nanoparticle interactions. With our custom image analysis method, we track the trajectories of nanoparticle movement with high precision from a stack of relatively noisy images obtained using liquid cell transmission electron microscopy. In a time frame of minutes, Pt-Fe nanoparticles self-assembled into a loosely packed hcp lattice. The energetics and stability of the dynamic assembly were studied quantitatively. From velocity and diffusion measurements, we experimentally determined the magnitude of forces between single particles and the related physical properties. The results illustrate that long-range anisotropic forces drive the formation of chains, which then clump and fold to maximize close range van der Waals interactions.

To quantitatively study the coupled dynamic behavior of vehicles in collision with semirigid guardrails, a coupled numerical model is established based on the finite element method. This model comprehensively integrates the nonlinear dynamic behavior of both the vehicle body and the guardrail structure. We validate the numerical results by comparing them with experimental findings and theoretical empirical formulas, confirming the accuracy of the coupled numerical model. This quantitative study investigates the influence of vehicle speed, column wall thickness, and collision angle on this coupled dynamic behavior to help optimize practical guardrail engineering designs. The results indicate that the sensitivity values of the collision speed, column wall thickness, and collision angle according to the baseline model are 1.0, 1.0, and 0.741, respectively. The parameters with higher sensitivity values are the key factors to consider in designs. Thus, the coupled numerical model can be used to optimize the design of semirigid guardrails in practical engineering. [ABSTRACT FROM AUTHOR]

Ozone (O3) pollution is a severe air quality issue in China, posing a threat to human health and ecosystems. The climate change will affect O3 levels by directly changing physical and chemical processes of O3 and indirectly changing natural emissions of O3 precursors. In this study, near‐surface O3 concentrations in China in 2030 and 2060 are predicted using the process‐based interpretable Extreme Gradient Boosting (XGBoost) model integrated with multi‐source data. The results show that the climate‐driven O3 levels over eastern China are projected to decrease by more than 0.4 ppb in 2060 under the carbon neutral scenario (SSP1‐1.9) compared with the high emission scenario (SSP5‐8.5). Among this reduction, 80% is attributed to the changes in physical and chemical processes of O3 related to a cooler climate, while the remaining 20% is attributed to the reduced biogenic isoprene emissions. Plain Language Summary: O3 pollution is a severe air quality issue in China that threatens human health and ecosystem. Under the background of climate change, O3 pollution will continue to evolve in the future. Here, we predict near‐surface O3 concentrations in China in 2030 and 2060 based on an interpretable machine learning method, integrated with physical and chemical processes of O3, natural emissions of O3 precursors, and other multi‐source data. The direct (via changing physical and chemical processes of O3) and indirect (via changing natural emissions of O3 precursors) impacts of future climate change on O3 concentrations are quantitatively analyzed. It demonstrates that the climate‐driven O3 levels are projected to decrease by more than 0.4 ppb in 2060 over eastern China under a carbon neutral scenario relative to a high emission scenario. The changes in physical and chemical processes under climate change play a more important role in regulating O3 concentrations in the future than the changes in natural emissions. Key Points: Climate change influences O3 pollution in China through changing physical and chemical processes and natural precursor emissions of O3Physical and chemical processes play a dominant role in regulating future near‐surface O3 concentrations over eastern ChinaCarbon neutral scenario is an ideal pathway for China to mitigate both climate change and O3 pollution in 2060 [ABSTRACT FROM AUTHOR]

The climate commitment to achieving carbon neutrality before 2060 in China has been announced recently. In the context of pursuing carbon neutrality, sharing similar sources as greenhouse gases, aerosol particle and precursor emissions are projected to substantially decrease in China, which can potentially have a great impact on climate. Here, we investigate the effects of future aerosol reductions, because of achieving carbon neutrality, on solar and wind energy in China by using an earth system model. We show that significant reductions in aerosol emissions, particularly in eastern China, lead to increases in the surface downwelling shortwave radiation, surface air temperature and wind speed, which can further enhance the potential of solar and wind energy production. The findings underline that the pursuit of carbon neutrality can yield co‐benefits of not only mitigating climate change and air pollution but also fortifying the stability of renewable energy sources. Plain Language Summary: In response to China's commitment to achieve carbon neutrality by 2060, our study examines the potential impact of reducing aerosol emissions and greenhouse gases on solar and wind energy generation. Employing an earth system model, we observe significant reductions in aerosols, particularly in eastern China, resulting in increases in surface downwelling shortwave radiation, surface air temperature, and wind speed. These changes have promising implications for enhancing solar and wind energy production. Our research underscores the interconnected benefits of pursuing carbon neutrality, encompassing climate change mitigation, air quality improvement, and the enhancement of renewable energy reliability. Key Points: The effects of future aerosol reductions in China due to achieving carbon neutrality on solar and wind energy are investigatedAerosol emission reductions, especially in eastern China, increase surface downwelling shortwave radiation, temperature and wind speedClimate changes resulting from emission reductions under carbon neutrality enhance the potential of solar and wind energy [ABSTRACT FROM AUTHOR]

The production of glutamine (Gln) from NO3− and NH4+ requires ATP, reducing power, and carbon skeletons. Plants may redirect these resources to other physiological processes using Gln directly. However, feeding Gln as the sole nitrogen (N) source has complex effects on plants. Under optimal concentrations, Arabidopsis (Arabidopsis thaliana) seedlings grown on Gln have similar primary root lengths, more lateral roots, smaller leaves, and higher amounts of amino acids and proteins compared to those grown on NH4NO3. While high levels of Gln accumulate in Arabidopsis seedlings grown on Gln, the expression of GLUTAMINE SYNTHETASE1;1 (GLN1;1), GLN1;2, and GLN1;3 encoding cytosolic GS1 increases and expression of GLN2 encoding chloroplastic GS2 decreases. These results suggest that Gln has distinct effects on regulating GLN1 and GLN2 gene expression. Notably, Arabidopsis seedlings grown on Gln have an unexpected gene expression profile. Compared with NH4NO3, which activates growth-promoting genes, Gln preferentially induces stress- and defense-responsive genes. Consistent with the gene expression data, exogenous treatment with Gln enhances disease resistance in Arabidopsis. The induction of Gln-responsive genes, including PATHOGENESIS-RELATED1, SYSTEMIC ACQUIRED RESISTANCE DEFICIENT1, WRKY54, and WALL ASSOCIATED KINASE1, is compromised in salicylic acid (SA) biosynthetic and signaling mutants under Gln treatments. Together, these results suggest that Gln may partly interact with the SA pathway to trigger plant immunity. Exogenous glutamine promotes seedling growth, induces lateral root initiation, activates defense responses, and enhances disease resistance in Arabidopsis. [ABSTRACT FROM AUTHOR]

The well-known backward difference formula (BDF) of the third, the fourth and the fifth orders are investigated for time integration of the phase field crystal model. By building up novel discrete gradient structures of the BDF- |$\textrm{k}$| (⁠|$\textrm{k}=3,4,5$|⁠) formulas, we establish energy dissipation laws at the discrete levels and then obtain a priori solution estimates for the associated numerical schemes; however, we can not build any discrete energy dissipation law for the corresponding BDF-6 scheme because the BDF-6 formula itself does not have any discrete gradient structures. With the help of the discrete orthogonal convolution kernels and Young-type convolution inequalities, some concise |$L^{2}$| norm error estimates (with respect to the starting data in the |$L^{2}$| norm) are established via the discrete energy technique. To the best of our knowledge, this is the first time such type |$L^{2}$| norm error estimates of non-A-stable BDF schemes are obtained for nonlinear parabolic equations. Numerical examples are presented to verify and support the theoretical analysis. [ABSTRACT FROM AUTHOR]

Interprovincial disparities in carbon emissions from the construction industry (CECI) are an important challenge for future emissions reductions. Based on the CECI data of 30 provinces in China from 2010 to 2020, the interprovincial equity and decoupling of CECI were examined in this study. The conclusions are as follows: (1): The main CECI growth regions were the eastern Bohai Rim region and the Pearl River Delta region. Heilongjiang basically achieved a CECI carbon peak in 2016. (2) The three northeastern provinces and western provinces were the main high–high and low–low aggregation areas, respectively. The greatest degree of inequality was found in the western provinces. The inequality between the eastern and western areas was the largest, while the inequality between the central and western areas was the smallest. The inequality in CECI in the north–south region decreased year by year. (3) The decoupling status of Shandong and some western provinces has significantly worsened, while the decoupling status of Sichuan, Yunnan, and some eastern developed provinces has been improving. These conclusions will contribute to the improvement of regional emission reduction strategies. [ABSTRACT FROM AUTHOR]