ACS Earth and Space Chemistry最新文献

A Network Approach for the Accurate Characterization of Water Lines Observable in Astronomical Masers and Extragalactic Environments 准确描述天文增量器和银河系外环境中可观测到的水线的网络方法

IF 2.9 3区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

ACS Earth and Space Chemistry

Pub Date : 2024-08-09 DOI: 10.1021/acsearthspacechem.4c00161

W. Ubachs, A. Császár, M. Diouf, F. Cozijn, Roland Tóbiás

引用次数: 0

Reactant Discovery with an Ab Initio Nanoreactor: Exploration of Astrophysical N-Heterocycle Precursors and Formation Pathways 利用 Ab Initio 纳米反应器发现反应物：探索天体物理 N-杂环前体和形成途径

IF 2.9 3区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

ACS Earth and Space Chemistry

Pub Date : 2024-08-09 DOI: 10.1021/acsearthspacechem.4c00120

Sommer L. Johansen, Heejune Park, Lee-Ping Wang, Kyle N Crabtree

引用次数: 0

Vacuum Ultraviolet Photoionization of Methane-Water Clusters Leads to Methanol Formation 甲烷-水簇的真空紫外光电离导致甲醇的形成

IF 2.9 3区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

ACS Earth and Space Chemistry

Pub Date : 2024-08-09 DOI: 10.1021/acsearthspacechem.4c00151

Nureshan Dias, Alexander K. Lemmens, Anna Wannenmacher, Musahid||Dias, Ahmed

引用次数: 0

Unveiling the Nitrogen Chemistry of Titan with the Dragonfly Mass Spectrometer: Experimental Focus on Amines and Amides 用蜻蜓质谱仪揭开土卫六氮化学的神秘面纱：以胺和酰胺为实验重点

IF 2.9 3区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

ACS Earth and Space Chemistry

Pub Date : 2024-08-08 DOI: 10.1021/acsearthspacechem.4c00143

C. Freissinet, V. Moulay, Xiang Li, C. Szopa, A. Buch, Antoine Palanca, Victoria Da Poian, Alex Abello, D. Boulesteix, Sandrine Vinatier, S. Teinturier, Jennifer C. Stern, W. Brinckerhoff, M. Trainer

引用次数: 0

Advances in Reverse Weathering and Its Role in Clay Mineral Formation and the Carbon Dioxide Cycle 反向风化作用及其在粘土矿物形成和二氧化碳循环中的作用的研究进展

IF 3.4 3区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

ACS Earth and Space Chemistry

Pub Date : 2024-08-07 DOI: 10.1021/acsearthspacechem.4c00105

Kejun Zheng, Shangying Li, Yulong Gao, Wenzhe Meng, Hongfei Cheng

Reverse weathering plays a significant role in the cycle of atmospheric carbon dioxide (CO₂) and elements between oceanic and continental environments during the Earth’s evolution. Through summarizing various previous research on reverse weathering, this review found much evidence that suggested that reverse weathering commonly occurs in dynamic areas of element exchange and abundant material sources, such as river mouths, deltas, sedimentary basins, and deep-sea sediments, accompanied by the formation of authigenic clay minerals. These clay minerals, by incorporating elements including Si, K, Li, and Mg, are reburied and contribute to a crucial reverse weathering sink, resulting in maintaining an elemental balance between the ocean and land. Concurrently, the process of reverse weathering releases CO₂, which holds great significance in studying CO₂ anomalies in the paleoenvironment. The extensive formation of authigenic clay minerals during pre-Cambrian glaciations and the δ⁷Li shifts around the Permian–Triassic boundary and within the Cenozoic provide compelling evidence of the occurrence of reverse weathering. This evidence sheds light on explaining the prolonged high CO₂ concentrations during pre-Cambrian glaciations, dramatic CO₂ concentration changes near the Permian–Triassic boundary, and cooling of the Cenozoic climate. It also offers new perspectives for paleoenvironmental reconstructions and the study of carbon cycling. This review can help to deeply understand the significant role of reverse weathering concerning clay mineral formation and the CO₂ cycle during Earth’s evolution, providing a theoretical foundation for future research endeavors.

在地球演化过程中，大气二氧化碳（CO2）和元素在海洋和大陆环境之间的循环中，逆风化作用发挥着重要作用。通过总结以往有关逆风化的各种研究，本综述发现许多证据表明，逆风化通常发生在元素交换活跃、物质来源丰富的区域，如河口、三角洲、沉积盆地和深海沉积物，并伴随着自生粘土矿物的形成。这些粘土矿物吸收了硅、钾、锂和镁等元素，被重新掩埋，成为重要的逆风化汇，从而维持了海洋和陆地之间的元素平衡。同时，逆风化过程释放出二氧化碳，这对研究古环境中的二氧化碳异常具有重要意义。前寒武纪冰川时期自生粘土矿物的广泛形成以及二叠纪-三叠纪边界附近和新生代内的δ7Li变化为逆风化的发生提供了令人信服的证据。这些证据有助于解释前寒武纪冰川时期二氧化碳浓度长期居高不下、二叠纪-三叠纪边界附近二氧化碳浓度的剧烈变化以及新生代气候变冷的原因。它还为古环境重建和碳循环研究提供了新的视角。这篇综述有助于深入理解地球演化过程中反向风化作用对粘土矿物形成和二氧化碳循环的重要作用，为今后的研究工作提供了理论基础。

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引用次数: 0

Molecular Structure and Rotational Dynamics in the Acetonitrile:Acetylene (1:2) Plastic Co-crystal at Titan Conditions 钛条件下乙腈：乙炔（1:2）塑料共晶体的分子结构和旋转动力学

IF 3.4 3区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

ACS Earth and Space Chemistry

Pub Date : 2024-08-06 DOI: 10.1021/acsearthspacechem.4c00157

Atul C. Thakur, Richard C. Remsing

The surface of Saturn’s moon Titan is coated with small-molecule organic solids termed cryominerals. Cryominerals play an analogous role to minerals on Earth in Titan’s surface geology and geochemistry. To develop a predictive understanding of Titan’s surface geochemistry, we need to characterize the structure and dynamics of cryominerals at the molecular scale. We use ab initio molecular dynamics simulations to quantify the structure and dynamics of the acetonitrile:acetylene (1:2) co-crystal at Titan surface conditions. We suggest that acetonitrile:acetylene is in a plastic phase, in which acetonitrile molecules are dynamically disordered about the N–C–C axis on sub-picosecond timescales, and that this rotational, plastic disorder persists at least to temperatures of 30 K. We anticipate that many cryominerals may have plastic phases at or near Titan surface conditions, and understanding this disorder will be crucial to predicting chemistry on Titan’s surface.

土星卫星土卫六的表面覆盖着被称为低温矿物质的小分子有机固体。低温矿物质在土卫六表面地质和地球化学中的作用类似于地球上的矿物。为了对土卫六表面地球化学有一个预测性的了解，我们需要在分子尺度上描述低温矿物的结构和动力学特征。我们利用ab initio分子动力学模拟来量化土卫六表面条件下乙腈：乙炔（1:2）共晶体的结构和动力学。我们认为乙腈：乙炔处于塑性相，其中乙腈分子在亚皮秒时间尺度上围绕 N-C-C 轴发生动态无序，这种旋转塑性无序至少持续到 30 K 的温度。

引用次数: 0

Sensitivity Analysis and Uncertainty Quantification of PFAS Fate and Transport in Heterogeneous Riparian Sediments 异质河岸沉积物中全氟辛烷磺酸命运与迁移的敏感性分析和不确定性量化

IF 2.9 3区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

ACS Earth and Space Chemistry

Pub Date : 2024-08-06 DOI: 10.1021/acsearthspacechem.4c0003710.1021/acsearthspacechem.4c00037

Pei Li*, Jeffery T. McGarr, Farzad Moeini, Zhenxue Dai and Mohamad Reza Soltanian*,

Per- and polyfluoroalkyl substances (PFAS) are surface-active contaminants, which are detected in groundwater globally, presenting serious health concerns. The vadose zone and surface water are recognized as primary sources of PFAS contamination. Previous studies have explored PFAS transport and retention mechanisms in the vadose zone, revealing that adsorption at interfaces and soil/sediment heterogeneity significantly influences PFAS retention. However, our understanding of how surface water–groundwater interactions along river corridors impact PFAS transport remains limited. To analyze PFAS transport during surface water–groundwater interactions, we performed saturated–unsaturated flow and reactive transport simulations in heterogeneous riparian sediments. Incorporating uncertainty quantification and sensitivity analysis, we identified key physical and geochemical sediment properties influencing PFAS transport. Our models considered aqueous-phase transport and adsorption both at the air–water interface (AWI) and the solid-phase surface. We tested different cases of heterogeneous sediments with varying volume proportions of higher permeability sediments, conducting 2000 simulations for each case, followed by global sensitivity and response surface analyses. Results indicate that sediment porosities, which are correlated to permeabilities, are crucial for PFAS transport in riparian sediments during river stage fluctuations. High-permeable sediment (e.g., sandy gravel, sand) is the preferential path for the PFAS transport, and low-permeable sediment (e.g., silt, clay) is where PFAS is retained. Additionally, the results show that adsorption at interfaces (AWI and solid phase) has a small impact on PFAS retention in riparian environments. This study offers insights into factors influencing PFAS transport in riparian sediments, potentially aiding the development of strategies to reduce the risk of PFAS contamination in groundwater from surface water.

全氟烷基和多氟烷基物质（PFAS）是一种表面活性污染物，在全球范围内的地下水中都检测到了这种物质，引起了严重的健康问题。含水层和地表水被认为是 PFAS 污染的主要来源。以往的研究探索了 PFAS 在黏土带的迁移和滞留机制，揭示了界面吸附和土壤/沉积物异质性对 PFAS 滞留的重大影响。然而，我们对河流走廊地表水-地下水相互作用如何影响 PFAS 迁移的了解仍然有限。为了分析地表水-地下水相互作用过程中 PFAS 的迁移，我们在异质河岸沉积物中进行了饱和-非饱和流动和反应迁移模拟。结合不确定性量化和敏感性分析，我们确定了影响 PFAS 迁移的关键沉积物物理和地球化学特性。我们的模型考虑了水相迁移以及空气-水界面 (AWI) 和固相表面的吸附。我们测试了不同情况的异质沉积物以及不同体积比例的高渗透性沉积物，对每种情况进行了 2000 次模拟，然后进行了全局敏感性和响应面分析。结果表明，沉积物孔隙率与渗透率相关，是河段波动期间全氟辛烷磺酸在河岸沉积物中迁移的关键。高渗透性沉积物（如沙砾、沙）是全氟辛烷磺酸迁移的首选路径，而低渗透性沉积物（如淤泥、粘土）则是全氟辛烷磺酸滞留的地方。此外，研究结果表明，界面吸附（AWI 和固相）对河岸环境中 PFAS 的滞留影响较小。这项研究深入揭示了影响河岸沉积物中 PFAS 迁移的因素，可能有助于制定战略，降低地表水中 PFAS 污染地下水的风险。

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引用次数: 0

Sensitivity Analysis and Uncertainty Quantification of PFAS Fate and Transport in Heterogeneous Riparian Sediments 异质河岸沉积物中全氟辛烷磺酸命运与迁移的敏感性分析和不确定性量化

IF 3.4 3区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

ACS Earth and Space Chemistry

Pub Date : 2024-08-06 DOI: 10.1021/acsearthspacechem.4c00037

Pei Li, Jeffery T. McGarr, Farzad Moeini, Zhenxue Dai, Mohamad Reza Soltanian

Per- and polyfluoroalkyl substances (PFAS) are surface-active contaminants, which are detected in groundwater globally, presenting serious health concerns. The vadose zone and surface water are recognized as primary sources of PFAS contamination. Previous studies have explored PFAS transport and retention mechanisms in the vadose zone, revealing that adsorption at interfaces and soil/sediment heterogeneity significantly influences PFAS retention. However, our understanding of how surface water–groundwater interactions along river corridors impact PFAS transport remains limited. To analyze PFAS transport during surface water–groundwater interactions, we performed saturated–unsaturated flow and reactive transport simulations in heterogeneous riparian sediments. Incorporating uncertainty quantification and sensitivity analysis, we identified key physical and geochemical sediment properties influencing PFAS transport. Our models considered aqueous-phase transport and adsorption both at the air–water interface (AWI) and the solid-phase surface. We tested different cases of heterogeneous sediments with varying volume proportions of higher permeability sediments, conducting 2000 simulations for each case, followed by global sensitivity and response surface analyses. Results indicate that sediment porosities, which are correlated to permeabilities, are crucial for PFAS transport in riparian sediments during river stage fluctuations. High-permeable sediment (e.g., sandy gravel, sand) is the preferential path for the PFAS transport, and low-permeable sediment (e.g., silt, clay) is where PFAS is retained. Additionally, the results show that adsorption at interfaces (AWI and solid phase) has a small impact on PFAS retention in riparian environments. This study offers insights into factors influencing PFAS transport in riparian sediments, potentially aiding the development of strategies to reduce the risk of PFAS contamination in groundwater from surface water.

全氟烷基和多氟烷基物质（PFAS）是一种表面活性污染物，在全球范围内的地下水中都检测到了这种物质，引起了严重的健康问题。含水层和地表水被认为是 PFAS 污染的主要来源。以往的研究探索了 PFAS 在黏土带的迁移和滞留机制，揭示了界面吸附和土壤/沉积物异质性对 PFAS 滞留的重大影响。然而，我们对河流走廊地表水-地下水相互作用如何影响 PFAS 迁移的了解仍然有限。为了分析地表水-地下水相互作用过程中 PFAS 的迁移，我们在异质河岸沉积物中进行了饱和-非饱和流动和反应迁移模拟。结合不确定性量化和敏感性分析，我们确定了影响 PFAS 迁移的关键沉积物物理和地球化学特性。我们的模型考虑了水相迁移以及空气-水界面 (AWI) 和固相表面的吸附。我们测试了不同情况的异质沉积物以及不同体积比例的高渗透性沉积物，对每种情况进行了 2000 次模拟，然后进行了全局敏感性和响应面分析。结果表明，沉积物的孔隙率与渗透率相关，是河段波动期间全氟辛烷磺酸在河岸沉积物中迁移的关键。高渗透性沉积物（如沙砾、沙）是全氟辛烷磺酸迁移的首选路径，而低渗透性沉积物（如淤泥、粘土）则是全氟辛烷磺酸滞留的地方。此外，研究结果表明，界面吸附（AWI 和固相）对河岸环境中 PFAS 的滞留影响较小。这项研究深入揭示了影响河岸沉积物中 PFAS 迁移的因素，可能有助于制定战略，降低地表水中 PFAS 污染地下水的风险。

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引用次数: 0

Molecular Structure and Rotational Dynamics in the Acetonitrile:Acetylene (1:2) Plastic Co-crystal at Titan Conditions 钛条件下乙腈：乙炔（1:2）塑料共晶体的分子结构和旋转动力学

IF 2.9 3区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

ACS Earth and Space Chemistry

Pub Date : 2024-08-06 DOI: 10.1021/acsearthspacechem.4c0015710.1021/acsearthspacechem.4c00157

Atul C. Thakur, and , Richard C. Remsing*,

The surface of Saturn’s moon Titan is coated with small-molecule organic solids termed cryominerals. Cryominerals play an analogous role to minerals on Earth in Titan’s surface geology and geochemistry. To develop a predictive understanding of Titan’s surface geochemistry, we need to characterize the structure and dynamics of cryominerals at the molecular scale. We use ab initio molecular dynamics simulations to quantify the structure and dynamics of the acetonitrile:acetylene (1:2) co-crystal at Titan surface conditions. We suggest that acetonitrile:acetylene is in a plastic phase, in which acetonitrile molecules are dynamically disordered about the N–C–C axis on sub-picosecond timescales, and that this rotational, plastic disorder persists at least to temperatures of 30 K. We anticipate that many cryominerals may have plastic phases at or near Titan surface conditions, and understanding this disorder will be crucial to predicting chemistry on Titan’s surface.

土星卫星土卫六的表面覆盖着被称为低温矿物质的小分子有机固体。低温矿物质在土卫六表面地质和地球化学中的作用类似于地球上的矿物。为了对土卫六表面地球化学有一个预测性的了解，我们需要在分子尺度上描述低温矿物的结构和动力学特征。我们利用ab initio分子动力学模拟来量化土卫六表面条件下乙腈：乙炔（1:2）共晶体的结构和动力学。我们认为乙腈：乙炔处于塑性相，其中乙腈分子在亚皮秒时间尺度上围绕 N-C-C 轴发生动态无序，这种旋转塑性无序至少持续到 30 K 的温度。

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引用次数: 0

Structural Composition and Molecular Weight Distribution of Dissolved Organic Matter in Bituminous Oil Sand from Okitipupa, Southern Nigeria 尼日利亚南部 Okitipupa 沥青油砂中溶解有机物的结构组成和分子量分布

IF 3.4 3区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

ACS Earth and Space Chemistry

Pub Date : 2024-08-05 DOI: 10.1021/acsearthspacechem.4c00062

Gbenga Aladekoyi, Emmanuel G. Olumayede, Samuel O. Olusanya, Patricia A. Heiden, Simeon K. Schum

The structural and exact molecular weight composition of the dissolved organic matter present in the oil sand from Okitipupa was investigated. Microscopic and spectroscopic methods were employed to determine the mineral composition and molecular structure of the compounds detected in the extracted bitumen. The extracted composite (dichloromethane/toluene solvent (D:T) ratio was 1:1 (50 mL each) and the sample-to-solvent ratio was 1:2.5 at 60 °C and 300 r/min. Elemental quantification of the oil sand from P1 (Loda) and P2 (Idiopopo) indicated a vast interaction of bitumen with clay minerals through their forms and compositions. The highest extractive quality of the compounds was obtained from P1 using 50:50 D:T extraction. P1 indicated an appreciable percentage of organic compounds with a maximum number of asphaltenes and aromatics as major components of bitumen, saturates, and resin. In P1, high concentrations of heteroatoms like nitrogen, oxygen, sulfur, and metals contributed to an increase in the viscosity and bonding of bitumen with embedded minerals compared to others. Oil sand in this region consists of complex heteroatomic compounds. Meanwhile, the van Krevelen plot revealed that the majority of formulas are in the regions H/C 0.5–2.5 m/z and O/C 0.1–0.5 m/z, which confirmed the diversity in the distribution of mass formulas for the samples. This revealed an important suggestion for understanding the geochemistry and exploitation of bitumen.

研究了奥基提普帕油砂中溶解有机物的结构和确切分子量组成。采用显微镜和光谱方法确定了提取的沥青中检测到的化合物的矿物成分和分子结构。在 60 °C 和 300 r/min 的条件下，萃取复合剂（二氯甲烷/甲苯溶剂 (D:T) 的比例为 1:1（各 50 mL），样品与溶剂的比例为 1:2.5。对 P1（Loda）和 P2（Idiopopo）油砂进行的元素定量分析表明，沥青与粘土矿物通过其形态和成分发生了巨大的相互作用。P1 采用 50:50 D:T 萃取法提取的化合物质量最高。P1 表明有机化合物的比例相当高，沥青的主要成分沥青烯和芳烃的数量最多，饱和物和树脂也是如此。在 P1 中，氮、氧、硫和金属等杂原子的浓度较高，与其他成分相比，这有助于增加沥青的粘度和与嵌入矿物的粘合力。该地区的油砂由复杂的杂原子化合物组成。同时，van Krevelen 图显示，大多数公式位于 H/C 0.5-2.5 m/z 和 O/C 0.1-0.5 m/z 区域，这证实了样品质量公式分布的多样性。这为了解沥青的地球化学和开采提供了重要建议。

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引用次数: 0