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Metal Zn anode encounters uncontrolled dendrite growth, resulting in poor cycling stability and low coulombic efficiency (CE). Herein, a novel approach for oriented‐electrochemical etching of Zn (ECE‐Zn) in deep eutectic solvent (DES) is presented to adjust the interface concentration and electric fields, effectively mitigating intractable issues. The oriented etches off the crystal edges between the (002), (100), and (101) principal crystal planes of commercial Zn foil, subsequently etches the (100) and (101) crystal planes, resulting in the formation well‐organized Zn columns. Comprehensive experimental investigations and theoretical analyses reveal that Zn ions directionally nucleate and grow between Zn columns, enabling epitaxial growth at the (002) crystal plane. The ECE‐Zn‐2 anodes demonstrate remarkable stability, along with low nucleation and polarization voltages. Specifically, the symmetric ECE‐Zn‐2 cells show sustained operation for 5400 h, and long‐term 10 000 cycles at 40 mA cm−2. More significantly, the asymmetric cells exhibit an average CE as high as 99.92% over 6000 cycles at 5.0 mA cm−2. When assembled with a V2O5 cathode, a high retention of 81.5% can be maintained even under severe condition (N/P ratio of 7.35). This strategy of oriented‐electrochemical etching for commercial Zn opens up a new pathway for dendrite‐free Zn metal anode. [ABSTRACT FROM AUTHOR]

The intense changes in glaciers in the southeastern Tibetan Plateau (SETP) have essential impacts on regional water resource management. In order to study the seasonal fluctuations of glaciers in this region and their relationship with climate change, we focus on the Yigong Zangbo River Basin in the SETP, extract the annual and seasonal variations of glaciers in the basin during 2018–2023, and analyze their spatio-temporal characteristics through the seasonal-trend decomposition using the LOESS (STL) method. Finally, combining the Extreme Gradient Boosting (XGBoost) model and the Shapley additive explanations (SHAP) model, we assess the comprehensive impact of meteorological factors such as temperature and snowfall on glacier changes. The results indicate that glaciers in the Yigong Zangbo River Basin experienced remarkable mass loss during 2018–2023, with an average annual melting rate of −0.83 ± 0.12 m w.e.∙yr−1. The glacier mass exhibits marked seasonal fluctuations, with increases in January–March (JFM) and April–June (AMJ) and noticeable melting in July–September (JAS) and October–December (OND). The changes over these four periods are 2.12 ± 0.04 m w.e., 0.93 ± 0.15 m w.e., −1.58 ± 0.19 m w.e., and −1.32 ± 0.17 m w.e., respectively. Temperature has been identified as the primary meteorological driver of glacier changes in the study area, surpassing the impact of snowfall. This study uses advanced altimetry data and meteorological data to monitor and analyze glacier changes, which provides valuable data for cryosphere research and also validates a set of replicable research methods, which provides support for future research in related fields. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are important atmospheric species that regulate the formation of both ozone and secondary organic aerosol. Compared with continental environments, VOC species, concentration and origins in marine environments were much less understood. Here, we conducted a 2‐month VOCs measurement using a proton‐transfer‐reaction mass spectrometer during the cruise of DongFangHong III research vessel over the eastern oceanic areas of China in winter 2019. According to the location of DongFangHong III, we divided our cruise into five regions: Qingdao port (QD), Zhoushan port (ZS), Bohai Sea (BHS), Yellow Sea (YS), and East China Sea (ECS). For most individual VOCs, their concentration exhibited the trend of ZS > QD > BHS > YS > ECS. A decreasing tendency was also found when the measurement location was progressively farther away from the coastline. Further, we performed Positive Matrix Factorization and retrieved five distinct VOC sources, including shipping emission, DongFangHong III emission, regional background, aged transport, and port and nearshore emission. Contributions of these five factors varied depending on the location, influenced by emission, atmospheric oxidation, and meteorological conditions. In addition, the inland anthropogenic sources were found to have a larger contribution than oceanic ones. Overall, by conducting in situ measurements of VOCs and source apportionment, this study complements the lack of information on the speciation, abundance, and sources of VOCs in the marine environment of China. Plain Language Summary: Compared to their better‐studied continental counterparts, marine volatile organic compounds (VOCs), critical precursors for ozone and secondary organic aerosol formation, are poorly characterized. In this study, we measured VOCs across China's eastern offshore areas during a winter 2019 voyage of the DongFangHong III. Our study region spanned five distinct areas: Qingdao port, Zhoushan port, and the Bohai, Yellow, and East China Seas. We observed a decline in most VOC concentrations sequentially from Zhoushan port to the East China Sea, and alongside increasing distance from the coastline. We identified five VOC sources, including emissions from shipping, the research vessel itself, regional background, aged transport, and combined port and nearshore activities. The influence of these sources varied by location, reflecting variations in emissions, atmospheric reactions, and local weather conditions. Notably, VOCs from inland anthropogenic activities overshadowed those from marine sources. This study provides critical insights into the VOC composition and sources over China's eastern marine environment, addressing a gap in our understanding of marine VOCs. Key Points: Volatile organic compounds (VOCs) across China's eastern offshore areas were measured during a winter 2019 voyage of the DongFangHong IIIMost VOC concentrations declined alongside increasing distance from the coastline5 VOC sources were identified with inland anthropogenic activities overshadowing those from marine sources [ABSTRACT FROM AUTHOR]

Two‐dimensional Ti3C2Tx MXene materials, with metal‐like conductivities and versatile terminals, have been considered to be promising surface modification materials for Zn‐metal‐based aqueous batteries (ZABs). However, the oxygen‐rich and hybridized terminations caused by conventional methods limit their advantages in inhibiting zinc dendrite growth and reducing corrosion‐related side reactions. Herein, −O‐depleted, −Cl‐terminated Ti3C2Tx was precisely fabricated by the molten salt electrochemical etching of Ti3AlC2, and controlled in situ terminal replacement from −Cl to unitary −S or −Se was achieved. The as‐prepared −O‐depleted and unitary‐terminal Ti3C2Tx as Zn anode coatings provided excellent hydrophobicity and enriched zinc‐ionophilic sites, facilitating Zn2+ horizontal transport for homogeneous deposition and effectively suppressing water‐induced side reactions. The as‐assembled Ti3C2Sx@Zn symmetric cell achieved a cycle life of up to 4200 h at a current density and areal capacity of 2 mA cm−2 and 1 mAh cm−2, respectively, with an impressive cumulative capacity of up to 7.25 Ah cm−2 at 5 mA cm−2//2 mAh cm−2. These findings provide an effective electrochemical strategy for tailoring −O‐depleted and unitary Ti3C2Tx surface terminals and advancing the understanding of the role of specific Ti3C2Tx surface chemistry in regulating the plating/stripping behaviors of metal ions. [ABSTRACT FROM AUTHOR]

Background: The 9th edition of the TNM Classification for lung cancer delineates M1c into two subcategories: M1c1 (Multiple extrathoracic lesions within a single organ system) and M1c2 (Multiple extrathoracic lesions involving multiple organ systems). Existing research indicates that patients with lung cancer in stage M1c1 exhibit superior overall survival compared to those in stage M1c2. The primary frontline therapy for patients with advanced non‐small cell lung cancer (NSCLC), lacking driver gene mutations, involves the use of immune checkpoint inhibitors (ICIs) combined with chemotherapy. Nevertheless, a dearth of evidence exists regarding potential survival disparities between NSCLC patients with M1c1 and M1c2 undergoing first‐line immune‐chemotherapy, and reliable biomarkers for predicting treatment outcomes are elusive. Serum metabolic profiles may elucidate distinct prognostic mechanisms, necessitating the identification of divergent metabolites in M1c1 and M1c2 undergoing combination therapy. This study seeks to scrutinize survival discrepancies between various metastatic patterns (M1c1 and M1c2) and pinpoint metabolites associated with treatment outcomes in NSCLC patients undergoing first‐line ICIs combined with chemotherapy. Method: In this study, 33 NSCLC patients lacking driver gene mutations diagnosed with M1c1, and 22 similarly diagnosed with M1c2 according to the 9th edition of TNM Classification, were enrolled. These patients received first‐line PD‐1 inhibitor plus chemotherapy. The relationship between metastatic patterns and progression‐free survival (PFS) in patients undergoing combination therapy was analyzed using univariate and multivariate Cox regression models. Serum samples were obtained from all patients before treatment initiation for untargeted metabolomics analysis, aiming to identify differential metabolites. Results: In the univariate analysis of PFS, NSCLC patients in M1c1 receiving first‐line PD‐1 inhibitor plus chemotherapy exhibited an extended PFS (HR = 0.49, 95% CI, 0.27–0.88, p = 0.017). In multivariate PFS analyses, these M1c1 patients receiving first‐line PD‐1 inhibitor plus chemotherapy also demonstrated prolonged PFS (HR = 0.45, 95% CI, 0.22–0.92, p = 0.028). The serum metabolic profiles of M1c1 and M1c2 undergoing first‐line PD‐1 inhibitors plus chemotherapy displayed notable distinctions. In comparison to M1c1 patients, M1c2 patients exhibited alterations in various pathways pretreatment, including platelet activation, linoleic acid metabolism, and the VEGF signaling pathway. Diminished levels of lipid‐associated metabolites (diacylglycerol, sphingomyelin) were correlated with adverse outcomes. Conclusion: NSCLC patients in M1c1, devoid of driver gene mutations, receiving first‐line PD‐1 inhibitors combined with chemotherapy, experienced superior outcomes compared to M1c2 patients. Moreover, metabolomic profiles strongly correlated with the prognosis of these patients, and M1c2 patients with unfavorable outcomes manifested distinct changes in metabolic pathways before treatment. These changes predominantly involved alterations in lipid metabolism, such as decreased diacylglycerol and sphingomyelin, which may impact tumor migration and invasion. [ABSTRACT FROM AUTHOR]

Nucleation and growth of aerosol particles from atmospheric vapors constitutes a major source of global cloud condensation nuclei (CCN). The fraction of newly formed particles that reaches CCN sizes is highly sensitive to particle growth rates, especially for particle sizes

Alkyl nitrates (RONO2) are an important class of nitrogen oxides reservoirs in the atmosphere and play a key role in tropospheric photochemistry. Despite the increasing concern for photochemical air pollution over China, the knowledge of characteristics and formation mechanisms of alkyl nitrates in this region is limited. We analyzed C1-C5 alkyl nitrates measured in Beijing at a polluted urban site in summer 2008 and at a downwind rural site in summers of both 2005 and 2008. Although the abundances of NOx and hydrocarbons were much lower at the rural site, the mixing ratios of RONO2 were comparable between both sites, emphasizing the regional nature of alkyl nitrate pollution. Regional transport of urban plumes governed the elevated RONO2 levels at the rural site. The concentrations of C1-C2 RONO2 were significantly higher at the rural site in 2008 compared to 2005 despite a decline in NOx and anthropogenic VOCs, mainly owing to enhanced contributions from biogenic VOCs. The photochemical formation regimes of RONO2 were evaluated by both a simplified sequential reaction model and a detailed master chemical mechanism box model. The observed C4-C5 RONO2 levels can be well explained by the photochemical degradation of n-butane and n-pentane, while the sources of C1-C3 RONO2 were rather complex. In addition to the C1-C3 alkanes, biogenic VOCs and reactive aromatics were also important precursors of methyl nitrate, and alkenes and long-chain alkanes contributed to the formation of C2-C3 RONO2. This study provides insights into the spatial distribution, inter-annual variation and photochemical formation mechanisms of alkyl nitrate pollution over the Beijing area.

Organic aerosols (OA) significantly contribute to haze pollution, threaten human health, and affect the radiation balance. However, real‐time tracking of OA evolution at the molecular level is limited, hindering a comprehensive understanding of their origins and behaviors. In this study, we investigated wintertime OA in a megacity in East China by combining simultaneous measurements from an extractive electrospray ionization time‐of‐flight mass spectrometer (EESI‐TOF) and a high‐resolution time‐of‐flight aerosol mass spectrometer (AMS) (HR‐TOF‐AMS). AMS results indicate that OA accounts for about 27% of non‐refractory submicron particulate matter (NR‐PM1) on average. EESI‐TOF data reveal that CxHyOz and CxHyN1–2Oz are the predominant OA components, contributing over 70% and 20%, respectively. Factorization analysis shows that while traffic, cooking, and biomass burning are major primary sources, most OA (>70% for EESI‐TOF, >55% for AMS) originate from secondary production. EESI‐TOF, although missing hydrocarbon‐like OA, excels in providing molecular information on oxygenated OA, identifying aromatics and aliphatics as possible key precursors. It further differentiates less oxidized secondary organic aerosols (SOA) into two factors with distinct molecular compositions, likely due to diverse source regions. Importantly, EESI‐TOF identifies two additional factors: one possibly related to plasticizers and another representing SOA formation from monoterpene oxidation by NO3 radicals. In conclusion, EESI‐TOF complements AMS by offering valuable molecular insights into the chemical processes underlying OA formation, especially in complex urban environments. Plain Language Summary: Organic aerosols (OA) are significant atmospheric constituents that profoundly influence weather patterns, climate dynamics, and public health, yet traditional techniques are difficult to effectively characterize the components and sources of organic aerosols. Here, we applied an extractive electrospray ionization time‐of‐flight mass spectrometer (EESI‐TOF) to explore the relevant characteristics of atmospheric organic aerosols during wintertime in the Yangtze River Delta region of eastern China and compared the results with traditional aerosol mass spectrometer (AMS) techniques. Near‐molecular level measurements of EESI‐TOF reveal that nitrogen‐free components dominate the total OA, and nitrogen‐containing components, which may represent organic nitrates, contribute less than 25%. Source apportionment indicates that traffic, cooking activity, and biomass burning are major primary sources of OA, while secondary production is the dominant OA source. Beyond the source attributions discernible from an AMS‐derived data set, EESI‐TOF furnishes enhanced perspectives on OA provenance due to its molecular‐level measurement. It enables the identification of primary OA sources potentially linked to plasticizer emissions and characterizes secondary sources tied to nocturnal monoterpene reactions. In summary, EESI‐TOF provides new insights into the components and sources of atmospheric OA in East China. Key Points: EESI‐TOF was applied to investigate the sources of atmospheric organic aerosols during wintertime in western YRDCxHyOz and CxHyN1–2Oz are the predominant components of OA, contributing over 70% and 20%Being highly complementary to AMS, EESI‐TOF provides a more comprehensive understanding of OA by capturing detailed molecular information [ABSTRACT FROM AUTHOR]

Purpose: To design a patient specific quality assurance (PSQA) process for the CyberKnife Synchrony system and quantify its dosimetric accuracy using a motion platform driven by patient tumor traces with rotation. Methods: The CyberKnife Synchrony system was evaluated using a motion platform (MODUSQA) and a SRS MapCHECK phantom. The platform was programed to move in the superior‐inferior (SI) direction based on tumor traces. The detector array housed by the StereoPhan was placed on the platform. Extra rotational angles in pitch (head down, 4.0° ± 0.15° or 1.2° ± 0.1°) were added to the moving phantom to examine robot capability of angle correction during delivery. A total of 15 Synchrony patients were performed SBRT PSQA on the moving phantom. All the results were benchmarked by the PSQA results based on static phantom. Results: For smaller pitch angles, the mean gamma passing rates were 99.75% ± 0.87%, 98.63% ± 2.05%, and 93.11% ± 5.52%, for 3%/1 mm, 2%/1 mm, and 1%/1 mm, respectively. Large discrepancy in the passing rates was observed for different pitch angles due to limited angle correction by the robot. For larger pitch angles, the corresponding mean passing rates were dropped to 93.00% ± 10.91%, 88.05% ± 14.93%, and 80.38% ± 17.40%. When comparing with the static phantom, no significant statistic difference was observed for smaller pitch angles (p = 0.1 for 3%/1 mm), whereas a larger statistic difference was observed for larger pitch angles (p < 0.02 for all criteria). All the gamma passing rates were improved, if applying shift and rotation correction. Conclusions: The significance of this work is that it is the first study to benchmark PSQA for the CyberKnife Synchrony system using realistically moving phantoms with rotation. With reasonable delivery time, we found it may be feasible to perform PSQA for Synchrony patients with a realistic breathing pattern. [ABSTRACT FROM AUTHOR]

The growth of newly formed particles through new particle formation (NPF) contributes a significant fraction to the cloud condensation nuclei, yet the driving mechanisms remain unclear, especially for polluted environments. To investigate the potential species contributing for nanoparticle growth in environments with significant anthropogenic influences, we measured the hygroscopicity of newly formed particles at 20–40 nm at a rural observational site in the North China Plain during winter 2018. Our results demonstrate that these particles were not very hygroscopic, with the mean hygroscopicity parameter κ of 0.13 ± 0.09. Clear differences in the inferred κ of the growing material responsible for the growth were observed among different events, indicating that even at the same region, the compounds driving particle growth may not be identical. This may be synergistically influenced by the NPF precursors, oxidants and meteorological conditions, suggesting complex mechanisms might co‐exist behind nanoparticle growth in polluted environments. Plain Language Summary: Particles newly formed through nucleation grow large enough to become cloud condensation nuclei which influences climate. However, the driving mechanisms and the key contributing species for nanoparticle growth are poorly understood. Here, we present direct measurements of the hygroscopicity of particles through new particle formation (NPF) that occurred in a rural environment in the North China Plain (NCP) during wintertime of 2018. Relatively low hygroscopicity of these newly formed particles were observed, suggesting less water‐soluble compounds drove the growth there. We also found that the hygroscopicity of the growing material responsible for nanoparticle growth was not identical on different NPF days. Our results reveal that the compounds driving the growth varied with different NPF conditions, deepening our understanding of nanoparticle growth in polluted environments. Key Points: Particles with sizes at 20–40 nm formed through new particle formation (NPF) are not very hygroscopic at rural North China Plain (NCP)The hygroscopicity parameter κ of the growing material varied from ∼0 to ∼0.1 among NPF eventsPrecursors, oxidants and meteorological conditions may synergistically determine the chemical compounds responsible for particle growth [ABSTRACT FROM AUTHOR]

This study analyzed the applicability of five long-term precipitation datasets in the Hang-Jia-Hu Plain of eastern China based on meteorological observation data. The accuracy of each dataset at different time scales (yearly, monthly) was analyzed. Besides, their spatiotemporal distributions and differences in precipitation event frequency were also compared. The results indicate that the high-resolution (1 day, 1 km) and long-term (1961–2019) gridded dataset for temperature and precipitation across China (HRLT) exhibited the best overall performance at the annual scale, while the long-term, gauge-based gridded precipitation dataset for the Chinese mainland (CHM_PRE) performed the best at the monthly scale. The dataset of monthly precipitation with a resolution of 1 km in China from 1960 to 2020 (HHU) and the China Meteorological Forcing Dataset (CMFD) tend to overestimate the local precipitation amounts, while the other three products are characterized by an underestimation. The mean result of the five datasets indicates a slight, statistically insignificant rise in precipitation, by 4.19 mm annually, with an overall multi-year average of 1303.28 mm. The analysis of the five datasets successfully captures the spatial precipitation patterns across the Hang-Jia-Hu Plain, characterized by higher precipitation levels in the southwest and lower in the northeast. Although the interannual variability displays general consistency, there are significant discrepancies in the interannual growth rates and the spatial distribution of significance across different regions. This study can provide a reference for the accuracy of precipitation data in the fields of hydrology, meteorology, agriculture, and ecology, facilitating the analysis of uncertainties in related research. [ABSTRACT FROM AUTHOR]

Reinforced concrete structures play a pivotal role in island and reef engineering projects. Given the resource constraints typical of island regions, substituting traditional manufactured sand aggregate with reef limestone not only reduces reliance on river sand but also addresses the issue of disposing of waste reef limestone slag generated during excavation. However, the performance characteristics of reef limestone concrete, particularly its bond strength with reinforcing steel, warrant further investigation. This is particularly true for the bond–slip behavior of the reinforcement. This study aims to elucidate the effects of various parameters on the bond performance between steel and reef limestone concrete through central pullout tests. These parameters include the type and diameter of the reinforcement, bond length, and loading rate. The investigation encompasses the analysis of load–slip curves, bond failure modes, and variations in bond stress. Additionally, using the Abaqus software, a numerical simulation was conducted to analyze the mesoscopic stress characteristics, thereby revealing the mechanisms of bond formation and failure modes between steel reinforcement and reef limestone concrete. The results indicate that the bond–slip curve for reef limestone concrete reinforced with ribbed rebars and Glass Fiber-Reinforced Polymer (GFRP) rebars can be broadly categorized into four phases: minor slip, slip, decline, and residual, with the residual phase exhibiting a wave-like pattern. The predominant failure modes in reef limestone concrete are either pulling out or splitting. The bond stress in reef limestone concrete decreases with an increase in rebar diameter and bond length; conversely, it increases with the loading rate, although the ultimate slip decreases. The mesoscopic failure characteristics of reinforced reef limestone concrete, as simulated in Abaqus, are consistent with the experimental outcomes. [ABSTRACT FROM AUTHOR]

Atmospheric aerosols not only cause severe haze pollution, but also affect climate through changes in cloud properties. However, during the haze pollution, aerosol‐cloud interactions are not well understood due to a lack of in situ observations. In this study, we conducted simultaneous observations of cloud droplet and particle number size distribution, together with supporting atmospheric parameters, from ground to cloud base in East China using a high‐payload tethered airship. We found that high concentrations of aerosols and cloud condensation nuclei were constrained below cloud, leading to the pronounced "Twomey effect" near the cloud base. The cloud inhibited the pollutants dispersion by reducing surface heat flux and thus deteriorated the near‐surface haze pollution. Satellite retrievals matched well with the in situ observations for low stratus clouds, while were insufficient to quantify aerosol‐cloud interactions for other cases. Our results highlight the importance to combine in situ vertical and satellite observations to quantify the aerosol‐cloud interactions. Plain Language Summary: Atmospheric aerosols, one of the major pollutants contributing to air pollution, also play an important role in climate through their interactions with clouds. The impact of aerosols on cloud properties remains the largest uncertainty in climate projections, partly due to a lack of in situ observations. Here, we conducted simultaneous observations on atmospheric aerosols and clouds from ground to 1,200 m above ground level in East China using a high‐payload tethered airship. We found aerosols number concentration was high below the clouds, which increased the cloud droplet concentration and decreased the cloud droplet diameter near cloud base. The clouds deteriorated the near‐surface air pollution, thus increasing exposure to hazardous levels. For low stratiform clouds, the satellite retrievals matched well with the observations, suggesting the satellite observation is a powerful tool to investigate clouds. However, the aerosol‐cloud interactions can still be underestimated by satellite measurements as the satellites record cloud properties near cloud top. We emphasize the need for direct in situ observations from the ground to high altitudes to quantify the effects of aerosols on cloud properties. Key Points: The pronounced Twomey effect near the cloud base was directly observed during the haze pollution by the tethered airship measurementThe observed Twomey effect at the cloud base in East China contradicts the satellite‐detected anti‐Twomey effect at the top of cloudsSatellite retrieved cloud effective radius is comparable to observation near cloud base of low stratus clouds, while is biased for others [ABSTRACT FROM AUTHOR]

Rechargeable aqueous Zn‐ion batteries (AZIBs) are one of the most promising alternatives for traditional energy‐storage devices because of their low cost, abundant resources, environmental friendliness, and inherent safety. However, several detrimental issues with Zn metal anodes including Zn dendrite formation, hydrogen evolution, corrosion and passivation, should be considered when designing advanced AZIBs. Moreover, these thorny issues are not independent but mutually reinforcing, covering many technical and processing parameters. Therefore, it is necessary to comprehensively summarize the issues facing Zn anodes and the corresponding strategies to develop roadmaps for the development of high‐performance Zn anodes. Herein, the failure mechanisms of Zn anodes and their corresponding impacts are outlined. Recent progress on improving the stability of Zn anode is summarized, including structurally designed Zn anodes, Zn alloy anodes, surface modification, electrolyte optimization, and separator design. Finally, this review provides brilliant and insightful perspectives for stable Zn metal anodes and promotes the large‐scale application of AZIBs in power grid systems. [ABSTRACT FROM AUTHOR]