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巴布亚新几内亚金元素地球化学特征及成矿预测

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地学前缘 2025年第1期32卷 194-204页

作者：徐鸣隰弯弯赵宇浩 Conrad KUMUL 吴大天 nathan MOSUSU 王天刚朱意萍姚仲友中国地质调查局南京地质调查中心江苏南京210016 巴布亚新几内亚矿产资源局巴布亚新几内亚莫尔兹比港121

巴布亚新几内亚位于太平洋板块和印度-澳大利亚板块的汇聚边缘,由3个构造单元组成。巴布亚新几内亚主要发育两种金矿化类型,即浅成低温热液型和斑岩型。2015—2018年开展的巴布亚新几内亚国家尺度地球化学填图,在高地地区、巴布亚半岛... 详细信息

巴布亚新几内亚位于太平洋板块和印度-澳大利亚板块的汇聚边缘,由3个构造单元组成。巴布亚新几内亚主要发育两种金矿化类型,即浅成低温热液型和斑岩型。2015—2018年开展的巴布亚新几内亚国家尺度地球化学填图,在高地地区、巴布亚半岛和新几内亚群岛采集了1399件水系沉积物样品。文章研究了巴布亚新几内亚金的地球化学背景、空间分布特征和成矿潜力。巴布亚新几内亚金含量为0.2~6188.0 ng/g,中位数(地球化学基准值)为1.5 ng/g,高于大陆地壳金元素丰度,略低于中国和澳大利亚的金地球化学基准值。由于广泛发育中酸性侵入岩、碱性侵入岩和碱性火山岩,由巴布亚褶皱带、新几内亚逆冲带、奥罗褶皱带、东部褶皱带、东巴布亚复合地体、巴布亚群岛、伯瓦尼-托里塞利地体和菲尼斯特雷地体组成的中央弧陆碰撞带的金基准值高于美拉尼西亚岩浆弧。地球化学图中,新几内亚逆冲带的钙碱性侵入杂岩体、美拉尼西亚岩浆弧中的钙碱性侵入杂岩体和富钾火山-侵入杂岩体与高金含量的区域具有高度耦合对应关系。这次工作圈定了7处金地球化学省和9处金地球化学异常区,主要分布于新几内亚逆冲带。8处异常区均具有发育浅成低温热液型或斑岩型金矿的潜力,可作为下一阶段巴布亚新几内亚金矿找矿方向。

关键词：国家尺度地球化学填图金异常浅成低温热液型斑岩型巴布亚新几内亚

巴布亚新几内亚镍元素地球化学特征及成矿潜力

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地学前缘 2025年第1期32卷 183-193页

作者：赵宇浩杨志明朱意萍 Kumul CONRAD 杜等虎 Mosusu nathan 王天刚姜瀚涛姚仲友中国地质调查局南京地质调查中心江苏南京210016 中国地质大学(北京) 北京100083 中国地质科学院地质研究所北京100037 巴布亚新几内亚矿产资源局莫尔兹比港121 中国黄金集团有限公司北京100011

巴布亚新几内亚位于太平洋板块和印度-澳大利亚板块的汇聚边缘,由3个构造单元组成。巴布亚新几内亚发育两种镍矿化类型。2015—2018年开展的巴布亚新几内亚国家尺度地球化学填图,在高地地区、巴布亚半岛和新几内亚群岛采集了1399件水系... 详细信息

巴布亚新几内亚位于太平洋板块和印度-澳大利亚板块的汇聚边缘,由3个构造单元组成。巴布亚新几内亚发育两种镍矿化类型。2015—2018年开展的巴布亚新几内亚国家尺度地球化学填图,在高地地区、巴布亚半岛和新几内亚群岛采集了1399件水系沉积物样品。本文研究了巴新镍的地球化学背景、空间分布特征和成矿潜力。巴新镍含量在2.7~2430.0μg/g之间,中位数(地球化学基准值)为42.0μg/g,接近上地壳镍元素丰度,高于欧洲、澳大利亚、北美和中国的镍地球化学基准值。由于广泛发育镁铁质-超镁铁质岩浆岩,由巴布亚褶皱带、新几内亚冲断带、奥罗褶皱带、东部褶皱带、东巴布亚复合地体、巴布亚群岛、伯瓦尼-托里塞利地体和菲尼斯特雷地体组成的中央弧陆碰撞带的镍基准值高于美拉尼西亚岩浆弧。地球化学图中,四月蛇绿岩、马鲁姆蛇绿岩和巴布亚超镁铁质岩带等蛇绿杂岩体与高镍含量的区域具有高度耦合对应关系。通过本次工作,圈定了7处镍地球化学省和8处镍地球化学异常区,主要分布于新几内亚逆冲带。8处异常区均具有发育红土型镍矿的潜力,可作为下一阶段巴新镍矿找矿方向。

关键词：国家尺度地球化学填图镍异常红土型矿化巴布亚新几内亚

Multidecadal Trends in Large-Scale Annual Mean SATa Based on CMIP5 Historical Simulations and Future Projections

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Engineering 2017年第1期3卷 136-143页

作者： Nan Xing jianping Li lanning Wang College of Global Change and Earth System Science Beijing Normal University Belting 100875 China Belting Meteorological Observatory Belting 100089 China joint Center for Global Change Studies Beijing 100875 China

Based on observations and Coupled Model lntercomparison Project Phase 5 （CMIP5） results, multidecadal variations and trends in annual mean surface air temperature anomalies （SATa） at global, hemispheric, and hemispheric land and ocean scales in the past and under the future scenarios of two representative concentration pathways （RCPs） are analyzed. Fifteen models are selected based on their performances in capturing the temporal variability, long-term trend, multidecadal variations, and trends in global annual mean SATa. Observational data analysis shows that the multidecadal variations in annual mean SATa of the land and ocean in the northern hemisphere （NH） and of the ocean in the southern hemisphere （SH） are similar to those of the global mean, showing an increase during the 1900-1944 and 1971-2000 periods, and flattening or even cooling during the 1945-1970 and 2001-2013 periods. These observed characteristics are basically reproduced by the models. However, SATa over SH land show an increase during the 1945-1970 period, which differs from the other hemispheric scales, and this feature is not captured well by the models. For the recent hiatus period （2001-2013）, the projected trends of BCC-CSM1-1-m, CMCC-CM, GFDL-ESM2M, and NorESM1-ME at the global and hemispheric scales are closest to the observations based on RCP4.5 and RCP8.5 scenarios, suggesting that these four models have better projection capability in SATa. Because these four models are better at simulating and projecting the multidecadal trends of SATa, they are selected to analyze future SATa variations at the global and hemispheric scales during the 2006-2099 period. The selected multi-model ensemble （MME） projected trends in annual mean SATa for the globe, NH, and SH under RCP4.5 （RCP8.5） are 0.17 （0.29） ℃, 0.22 （0.36） ℃, and 0.11 （0.23） ℃-decade-1 in the 21st century, respectively. These values are significantly lower than the projections of CMIP5 MME without model selection.

关键词： Surface air temperature anomalies (SATa) Multidecadal trend Coupled Model lntercomparison Project Phase 5 (CMIPS) Projection

Validating neural networks for spectroscopic classification on a universal synthetic dataset

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npj Computational Materials 2023年第1期9卷 1325-1336页

作者： jan Schuetzke nathan j.Szymanski Markus Reischl Institute for Automation and Applied Informatics Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Department of Materials Science&Engineering Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Department of Materials Science&Engineering UC BerkeleyBerkeleyCA 94720USA

To aid the development of machine learning models for automated spectroscopic data classification,we created a universal synthetic dataset for the validation of their *** dataset mimics the characteristic appearance of experimental measurements from techniques such as X-ray diffraction,nuclear magnetic resonance,and Raman spectroscopy among *** applied eight neural network architectures to classify artificial spectra,evaluating their ability to handle common experimental *** all models achieved over 98%accuracy on the synthetic dataset,misclassifications occurred when spectra had overlapping peaks or *** found that non-linear activation functions,specifically ReLU in the fully-connected layers,were crucial for distinguishing between these classes,while adding more sophisticated components,such as residual blocks or normalization layers,provided no performance *** on these findings,we summarize key design principles for neural networks in spectroscopic data classification and publicly share all scripts used in this study.

关键词： spectroscopic adding classify

Functional perspectives on tropical tree demography and forest dynamics

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Ecological Processes 2019年第1期8卷 1-11页

作者： Samantha j.Worthy nathan G.Swenson Department of Biology University of MarylandCollege ParkMD 20742USA

Disentangling the processes that drive population,community and whole forest structure and dynamics is a *** becomes a grand challenge in the tropics where there are a large number of species,small population sizes,less research infrastructure,and a relatively smaller number of researchers compared to the temperate *** this grand challenge,we argue,requires detailed knowledge of the functioning of individuals and *** this end,researchers frequently employ plant functional traits to study tree populations and ***,we review this approach by first providing a basic background regarding the major trait axes generally of *** then discuss how these axes may be or have been applied from ecosystem to community and population *** doing so,we highlight where the functional trait research program has failed in tropical tree ecology and where it can be improved or ***,we provide a perspective regarding how functional trait and emerging‘omics approaches can be integrated to address large questions facing the *** intention throughout is to provide an entryway into this literature for an early career researcher rather than a comprehensive review of all possible studies that have taken place in tropical forests.

关键词： Demographic rate Functional diversity Functional trait Transcriptome Tropical forest Tropical rain forest

Small molecule fluorescent probes of protein vicinal dithiols

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Chinese Chemical Letters 2019年第10期30卷 1704-1716页

作者： Guodong Hu Huiyi jia lanning Zhao Dong-Hyung Cho jianguo Fang State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China School of Life Sciences Kyungpook National UniversityDaegu 41566Republic of Korea

The vicinal dithiol motif is widely present in proteins, and is critical for proteins’ structures and *** recent years, a variety of fluorescent probes with high specificity and outstanding optical properties for sensing protein vicinal dithiols have been developed. In this review, we summarized the fluorescent probes of protein vicinal dithiols in literature. These probes are classified into four types based on their acceptor sites, i.e., biarsenical probes, monoarsenical probes, dimaleimide probes and diacrylate *** analyzing the properties of different probes, we expect that this review would help readers further understand the structural factors of these probes and provide the design strategy for novel fluorescent probes with improved properties.

关键词： Fluorescent probe Protein vicinal dithiols Arsenical probe Thiol redox Reaction-based probe

Integrated analysis of X-ray diffraction patterns and pair distribution functions for machine-learned phase identification

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npj Computational Materials 2024年第1期10卷 2780-2788页

作者： nathan j.Szymanski Sean Fu Ellen Persson Gerbrand Ceder Department of Mat.Sci.&Engineering UC BerkeleyBerkeleyCA 94720USA Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

To bolster the accuracy of existing methods for automated phase identification from X-ray diffraction(XRD)patterns,we introduce a machine learning approach that uses a dual representation whereby XRD patterns are augmented with simulated pair distribution functions(PDFs).A convolutional neural network is trained directly on XRD patterns calculated using physics-informed data augmentation,which accounts for experimental artifacts such as lattice strain and crystallographic texture.A second network is trained on PDFs generated via Fourier transform of the augmented XRD *** inference,these networks classify unknown samples by aggregating their predictions in a confidenceweighted *** show that such an integrated approach to phase identification provides enhanced accuracy by leveraging the benefits of each model’s input *** networks trained on XRD patterns provide a reciprocal space representation and can effectively distinguish large diffraction peaks in multi-phase samples,networks trained on PDFs provide a real space representation and perform better when peaks with low intensity become *** findings underscore the importance of using diverse input representations for machine learning models in materials science and point to new avenues for automating multi-modal characterization.

关键词： phase distribution diffraction

Adaptively driven X-ray diffraction guided by machine learning for autonomous phase identification

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npj Computational Materials 2023年第1期9卷 2036-2043页

作者： nathan j.Szymanski Christopher j.Bartel Yan Zeng Mouhamad Diallo Haegyeom Kim Gerbrand Ceder Department of Materials Science&Engineering UC BerkeleyBerkeleyCA 94720USA Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Machine learning(ML)has become a valuable tool to assist and improve materials characterization,enabling automated interpretation of experimental results with techniques such as X-ray diffraction(XRD)and electron *** ML models are fast once trained,there is a key opportunity to bring interpretation in-line with experiments and make on-the-fly decisions to achieve optimal measurement effectiveness,which creates broad opportunities for rapid learning and information extraction from ***,we demonstrate such a capability with the development of autonomous and adaptive *** coupling an ML algorithm with a physical diffractometer,this method integrates diffraction and analysis such that early experimental information is leveraged to steer measurements toward features that improve the confidence of a model trained to identify crystalline *** validate the effectiveness of an adaptive approach by showing that ML-driven XRD can accurately detect trace amounts of materials in multi-phase mixtures with short measurement *** improved speed of phase detection also enables in situ identification of short-lived intermediate phases formed during solid-state reactions using a standard in-house *** findings showcase the advantages of in-line ML for materials characterization and point to the possibility of more general approaches for adaptive experimentation.

关键词： phase diffraction autonomous

Iron and non-alcoholic fatty liver disease

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World journal of Gastroenterology 2016年第36期22卷 8112-8122页

作者： Laurence j Britton V nathan Subramaniam Darrell HG Crawford Gallipoli Medical Research Institute The University of Queensland Greenslopes Private Hospital Brisbance Queensland 4120 Australia The Princess Alexandra Hospital Queensland 4120 Australia QIMR Berghofer Medical Research Institute Queensland 4120 Australia

The mechanisms that promote liver injury in non-alcoholic fatty liver disease(NAFLD) are yet to be thoroughly elucidated. As such, effective treatment strategies are lacking and novel therapeutic targets are required. Iron has been widely implicated in the pathogenesis of NAFLD and represents a potential target for treatment. Relationships between serum ferritin concentration and NAFLD are noted in a majority of studies, although serum ferritin is an imprecise measure of iron loading. Numerous mechanisms for a pathogenic role of hepatic iron in NAFLD have been demonstrated in animal and cell culture models. However, the human data linking hepatic iron to liver injury in NAFLD is less clear, with seemingly conflicting evidence, supporting either an effect of iron in hepatocytes or within reticulo-endothelial cells. Adipose tissue has emerged as a key site at which iron may have a pathogenic role in NAFLD. Evidence for this comes indirectly from studies that have evaluated the role of adipose tissue iron with respect to insulin resistance. Adding further complexity, multiple strands of evidence support an effect of NAFLD itself on iron metabolism. In this review, we summarise the human and basic science data that has evaluated the role of iron in NAFLD pathogenesis.

关键词： Iron Fatty liver Liver steatosis Insulin resistance Steatohepatitis Diabetes mellitus Adipose tissue