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研究发现全球地表水和地下水PFAS污染的环境负担被低估 快报文章
资源环境快报，2024年第8期
作者:  廖琴
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Per- and Polyfluoroalkyl Substances (PFAS)  Water Contamination  Environmental Burden  
研究人员开发新方法识别全球表层土壤砷污染热点地区 快报文章
资源环境快报，2024年第1期
作者:  廖 琴
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Deep Learning  Arsenic Contamination  Topsoil  
美国科学家开发出快速修复土壤污染的高温电热技术 快报文章
资源环境快报，2023年第20期
作者:  廖 琴
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Soil Contamination  High-temperature Electrothermal Remediation  Heavy Metals  Persistent Organic Pollutants  
北极多年冻土退化或致工业遗址污染物排放风险增大 快报文章
地球科学快报，2023年第08期
作者:  刘文浩
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Arctic  Permafrost  contamination  
湖泊沉积物显示数十年的煤灰污染 快报文章
资源环境快报，2022年第19期
作者:  吴秀平
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Coal  lake  Contamination  
新方法可快速监测饮用水污染 快报文章
资源环境快报，2021年第21期
作者:  吴秀平
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drinking water  monitoring of contamination  
Hydrothermal (NN)-N-15-N-15 abundances constrain the origins of mantle nitrogen 期刊论文
NATURE, 2020, 580 (7803) : 367-+
作者:  Zhao, Steven;  Jang, Cholsoon;  Liu, Joyce;  Uehara, Kahealani;  Gilbert, Michael;  Izzo, Luke;  Zeng, Xianfeng;  Trefely, Sophie;  Fernandez, Sully;  Carrer, Alessandro;  Miller, Katelyn D.;  Schug, Zachary T.;  Snyder, Nathaniel W.;  Gade, Terence P.;  Titchenell, Paul M.;  Rabinowitz, Joshua D.;  Wellen, Kathryn E.
收藏  |  浏览/下载：14/0  |  提交时间：2020/05/13

Nitrogen is the main constituent of the Earth'  s atmosphere, but its provenance in the Earth'  s mantle remains uncertain. The relative contribution of primordial nitrogen inherited during the Earth'  s accretion versus that subducted from the Earth'  s surface is unclear(1-6). Here we show that the mantle may have retained remnants of such primordial nitrogen. We use the rare (NN)-N-15-N-15 isotopologue of N-2 as a new tracer of air contamination in volcanic gas effusions. By constraining air contamination in gases from Iceland, Eifel (Germany) and Yellowstone (USA), we derive estimates of mantle delta N-15 (the fractional difference in N-15/N-14 from air), N-2/Ar-36 and N-2/He-3. Our results show that negative delta N-15 values observed in gases, previously regarded as indicating a mantle origin for nitrogen(7-10), in fact represent dominantly air-derived N-2 that experienced N-15/N-14 fractionation in hydrothermal systems. Using two-component mixing models to correct for this effect, the (NN)-N-15-N-15 data allow extrapolations that characterize mantle endmember delta N-15, N-2/Ar-36 and N-2/He-3 values. We show that the Eifel region has slightly increased delta N-15 and N-2/Ar-36 values relative to estimates for the convective mantle provided by mid-ocean-ridge basalts(11), consistent with subducted nitrogen being added to the mantle source. In contrast, we find that whereas the Yellowstone plume has delta N-15 values substantially greater than that of the convective mantle, resembling surface components(12-15), its N-2/Ar-36 and N-2/He-3 ratios are indistinguishable from those of the convective mantle. This observation raises the possibility that the plume hosts a primordial component. We provide a test of the subduction hypothesis with a two-box model, describing the evolution of mantle and surface nitrogen through geological time. We show that the effect of subduction on the deep nitrogen cycle may be less important than has been suggested by previous investigations. We propose instead that high mid-ocean-ridge basalt and plume delta N-15 values may both be dominantly primordial features.


  
Wafer-scale single-crystal hexagonal boron nitride monolayers on Cu (111) 期刊论文
NATURE, 2020, 579 (7798) : 219-+
作者:  Luong, Duy X.;  Bets, Ksenia V.;  Algozeeb, Wala Ali;  Stanford, Michael G.;  Kittrell, Carter;  Chen, Weiyin;  Salvatierra, Rodrigo V.;  Ren, Muqing;  McHugh, Emily A.;  Advincula, Paul A.;  Wang, Zhe;  Bhatt, Mahesh;  Guo, Hua;  Mancevski, Vladimir;  Shahsavari, Rouzbeh
收藏  |  浏览/下载：79/0  |  提交时间：2020/07/03

Ultrathin two-dimensional (2D) semiconducting layered materials offer great potential for extending Moore'  s law of the number of transistors in an integrated circuit(1). One key challenge with 2D semiconductors is to avoid the formation of charge scattering and trap sites from adjacent dielectrics. An insulating van der Waals layer of hexagonal boron nitride (hBN) provides an excellent interface dielectric, efficiently reducing charge scattering(2,3). Recent studies have shown the growth of single-crystal hBN films on molten gold surfaces(4) or bulk copper foils(5). However, the use of molten gold is not favoured by industry, owing to its high cost, cross-contamination and potential issues of process control and scalability. Copper foils might be suitable for roll-to-roll processes, but are unlikely to be compatible with advanced microelectronic fabrication on wafers. Thus, a reliable way of growing single-crystal hBN films directly on wafers would contribute to the broad adoption of 2D layered materials in industry. Previous attempts to grow hBN monolayers on Cu (111) metals have failed to achieve mono-orientation, resulting in unwanted grain boundaries when the layers merge into films(6,7). Growing single-crystal hBN on such high-symmetry surface planes as Cu (111)(5,8) is widely believed to be impossible, even in theory. Nonetheless, here we report the successful epitaxial growth of single-crystal hBN monolayers on a Cu (111) thin film across a two-inch c-plane sapphire wafer. This surprising result is corroborated by our first-principles calculations, suggesting that the epitaxial growth is enhanced by lateral docking of hBN to Cu (111) steps, ensuring the mono-orientation of hBN monolayers. The obtained single-crystal hBN, incorporated as an interface layer between molybdenum disulfide and hafnium dioxide in a bottom-gate configuration, enhanced the electrical performance of transistors. This reliable approach to producing wafer-scale single-crystal hBN paves the way to future 2D electronics.


  
Exact Upscaling for Transport of Size-Distributed Colloids 期刊论文
WATER RESOURCES RESEARCH, 2019, 55 (2) : 1011-1039
作者:  Bedrikovetsky, P.;  Osipov, Y.;  Kuzmina, L.;  Malgaresi, G.
收藏  |  浏览/下载：4/0  |  提交时间：2019/11/26
upscaling  averaging  exact averaging of suspension-colloidal and reactive transport with distributed particle properties  reactive transport  exact solutions for 1-D reactive or colloidal flow for the upscaled system  aquifer contamination  
Decadal Delays in Groundwater Recovery from Nitrate Contamination Caused by Low O-2 Reduction Rates 期刊论文
WATER RESOURCES RESEARCH, 2018, 54 (12) : 9996-10012
作者:  Wild, Lisa M.;  Mayer, Bernhard;  Einsiedl, Florian
收藏  |  浏览/下载：10/0  |  提交时间：2019/04/09
mean transit time (MTT)  15N  O-2 reduction rate  denitrification  nitrate contamination