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The significance of cherts as markers of Ocean Plate Stratigraphy and paleoenvironmental conditions:New insights from the Neoproterozoic-Cambrian Blovice accretionary wedge,Bohemian Massif

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Geoscience Frontiers 2023年第1期14卷 162-180页

作者： LukášAckerman Jirízák Václav Kachlík jan pašava KarelZák Andreas pack František Veselovsky Ladislav Strnad Institute of Geology of the Czech Academy of Sciences Rozvojová269CZ-16500 Prague 6Czech Republic Czech Geological Survey Klárov3CZ-11821 Prague 1Czech Republic Institute of Geology and paleontology Faculty of ScienceCharles UniversityAlbertov 6Prague 12843Czech Republic Geowissenschaftliches Zentrum Universität GöttingenGoldschmidtstraβe 1D-37077 GöttingenGermany Laboratories of the Geological Institutes Faculty of ScienceCharles UniversityAlbertov 6Prague 12843Czech Republic

The Ediacaran to early Cambrian Blovice accretionary complex,Bohemian Massif,hosts abundant chert bodies that formed on an oceanic plate and were involved in subduction beneath the northern margin of *** relationships of cherts to their host,their microstructure and elemental as well as isotopic compositions revealed diverse processes of chert petrogenesis reflecting depositional environment and position on the oceanic *** deep-water cherts formed through a hydrothermal precipitation of silica-rich gels on outer trench swell of the subducted slab with none or only minor addition of terrigenous *** the contrary,the shallow-water cherts formed in lagoons on seamount slopes,and at least some of them represent a product of hydrothermal replacement of former carbonate and/or evaporite *** both chert types,the hydrothermal fluids were of low temperature and continuous pervasive hydrothermal alteration of oceanic crust,together with an elevated Si content in Neoproterozoic seawater,served as the major source of *** the other hand,minor carbon enrichment in chert is mostly linked to variable incorporation of organic matter that was deposited on the *** earth element(REE)systematics of the cherts indicate predominantly oxygenated environment for the shallow-water cherts whereas the deep-water cherts were deposited in diverse redox conditions,depending on their distance from hydrothermal *** these data,we demonstrate that the cherts once formed a part of Ocean Plate Stratigraphy(OPS)now dismembered and mixed with terrigenous siliciclastic material to form OPS mé*** our data with those from the existing literature,we show that cherts can serve as significant markers of OPS since the Archean,recording a complex interplay between seafloor-related volcanic(production of MORB-and OIB-like magmas)and sedimentary processes,hydrothermal activity at mid-ocean ridges and seamount chains as well as at outer slopes o

关键词： Chert Accretionary wedge Ediacaran Triple oxygen isotopes Strontium isotopes Ocean Plate Stratigraphy

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Geochemistry and mineralogy of platinum-group elements(PGE)in chromites from CentralnoyeⅠ,Polar Urals,Russia

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Geoscience Frontiers 2011年第1期2卷 81-85页

作者： jan paava Ilja Knésl Anna Vymazalová Ivan Vavrín Ludmila Ivanovna Gurskaya Leonid Ruslanovich Kolbantsev Czech Geological Survey Geologicka 6152 00 Praha 5Czech Republic All Russia Geological Research Institute(VSEGEI) 74 Srechy Pr.199 106 St.PetersburgRussia

The Polar Urals region of northern Russia is well known for large chromium （Cr）-bearing massifs with major chromite orebodies, including the Centralnoye I deposit in the Ray-Iz ultramafic massif of the Ural ophiolite belt. New data on platinum （Pt）-group elements （PGE）, geochemistry and mineralogy of the host dunite shows that the deposit has anomalous iridium （Ir） values. These values indicate the predominance of ruthenium--osmium--iridium （Ru--Os--Ir）-bearing phases among the platinum-group mineral （PGM） assemblage that is typical of mantle-hosted chromite ores. Low Pt values in chromites and increased Pt values in host dunites might reflect the presence of cumulus PGM grains. The most abundant PGM found in the chromite is erlichmanite （up to 15 μm）. Less common are cuproiridsite （up to 5 μm）, irarsite （up to 4--5 μm）, and laurite （up to 4 μm）. The predominant sulfide is heazlewoodite, in intergrowth with Ni--Fe alloys, sporadically with pentlandite, and rarely with pure nickel. Based on the average PGE values and esti- mated Cr-ore resources, the Centralnoye I deposit can be considered as an important resource of PGE.

关键词： Platinum-group elements Platinum-group minerals Chromite Ophiolites Centralnoye I deposit Polar Urals

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黑色页岩成矿作用—IGCP254项活动及最新进展

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地球科学进展 1990年第6期5卷 85-86页

作者： jan paava 吴志勇宋之光捷

1987年2月在巴黎,国际地质对比计划常委会第15次会议顺利地通过了254项“黑色页岩成矿作用”(1987—1991)的立项决议。1987年10月在捷克斯洛伐克Jesenik成立了以***(?)ava为主席的执行机构,包括美国、苏联、澳大利亚、芬兰、法国、联邦... 详细信息

1987年2月在巴黎,国际地质对比计划常委会第15次会议顺利地通过了254项“黑色页岩成矿作用”(1987—1991)的立项决议。1987年10月在捷克斯洛伐克Jesenik成立了以***(?)ava为主席的执行机构,包括美国、苏联、澳大利亚、芬兰、法国、联邦德国、匈牙利、波兰、委内瑞拉、中国和印度等在内的各国工作小组。目前,已有24个国家的300多位科研人员参加了IGCP项工作。该项目的最终目标首先是揭示黑色页岩建造的各种特征,包括恢复古环境和古地理条件、古构造位置及地球化学特征等。

关键词：页岩成矿作用黑色

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用三氧化铬-硫酸溶剂对黑色页岩铼-锇定年方法初探

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岩矿测试 2008年第4期27卷 245-249页

作者：刘华屈文俊王英滨任静杜安道 jan paava 孙文静国家地质实验测试中心北京100037 中国地质大学(北京)材料科学与化学工程学院北京100083 捷克地调局山东省第三地质矿产勘查院山东烟台264000

讨论了铼-锇同位素稀释法测定黑色页岩年龄的溶样方式,比较了王水和不同温度下CrO3-H2SO4的Carius管溶样技术,通过改进流程将铼空白控制在10pg之内,并结合高灵敏度的电感耦合等离子体质谱分析手段,初步研究建立了一种用CrO3-H2SO4溶剂... 详细信息

讨论了铼-锇同位素稀释法测定黑色页岩年龄的溶样方式,比较了王水和不同温度下CrO3-H2SO4的Carius管溶样技术,通过改进流程将铼空白控制在10pg之内,并结合高灵敏度的电感耦合等离子体质谱分析手段,初步研究建立了一种用CrO3-H2SO4溶剂准确测定黑色页岩年龄的方法。

关键词：同位素稀释等离子体质谱法铼-锇定年黑色页岩石流程空白三氧化铬-硫酸溶剂温度

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Liver transplantation and liver resection as alternative treatments for primary hepatobiliary and secondary liver tumors: Competitors or allies?

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Hepatobiliary & pancreatic Diseases International 2024年第2期23卷 111-116页

作者： jan Lerut Institute for Experimental and Clinical Research(IREC) Universitécatholique Louvain(UCL)Avenue Hippocrate 561200 Woluwe Saint PierreBrusselsBelgium

Although Starzl designed in the 1960’s liver transplantation(LT)to treat unresectable primary and also secondary liver tumors,transplantation still occupies a(too)small place in the respective therapeutic algorithms[1].Due to the lack of(any)selection criteria,the concept of transplantation became rapidly challenged because of the prohibitively high incidence of tumor recurrence[1–3].

关键词： liver tumors Liver

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Potential of molecular chaperones for treating Alzheimer’s disease

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Neural Regeneration Research 2024年第11期19卷 2343-2344页

作者： Gefei Chen jan Johansson Department of Biosciences and Nutrition Karolinska InstitutetHuddingeSweden Department of Cell and Molecular Biology Uppsala UniversityUppsalaSweden

Alzheimer’s disease(AD)is the most prevalent form of dementia,i.e.,progressive memory loss and profound cognitive dysfunction,resulting in a considerable societal *** the neuropathological level,the brains of AD patients exhibit amyloid-β(Aβ)plaques,neurofibrillary tangles,and neuroinflammation(Sala Frigerio and De Strooper,2016).

关键词： Alzheimer inflammation Aβ

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A fiducial approach to the nonparametric deconvolution problem:The discrete case

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Science China Mathematics 2024年第11期67卷 2653-2670页

作者： Yifan Cui jan Hannig Center for Data Science Zhejiang University Department of Statistics and Operations Research University of North Carolina at Chapel Hill

Fiducial inference is applied to nonparametric g-modeling in the discrete *** propose a computationally efficient algorithm to sample from the fiducial distribution and use the generated samples to construct point estimates and confidence *** study the theoretical properties of the fiducial distribution and perform extensive simulations in various *** proposed approach gives rise to good statistical performance in terms of the mean squared error of point estimators and coverage of confidence ***,we apply the proposed fiducial method to estimate the probability of each satellite site being malignant using gastric adenocarcinoma data with 844 patients.

关键词： confidence intervals empirical Bayes fiducial inference nonparametric deconvolution

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Solid Bi_(2)O_(3)-derived nanostructured metallic bismuth with high formate selectivity for the electrocatalytic reduction of CO_(2)

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 803-811页

作者： Xiaoyan Wang Safeer jan Zhiyong Wang Xianbo Jin College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationWuhan 430072China

CO_(2) electrochemical reduction(CO_(2)ER)is an important research area for carbon ***,available catalysts for CO_(2) reduction are still characterized by limited stability and ***,metallic bismuth(Bi)has emerged as a promising catalyst for CO_(2) ***,we report the solid cathode electroreduction of commercial micronized Bi2O3as a straightforward approach for the preparation of nanostructured ***-1.1 V versus reversible hydrogen electrode in a KHCO3aqueous electrolyte,the resulting nanostructure Bi delivers a formate current density of~40 mA·cm^(-2) with a current efficiency of~86%,and the formate selectivity reaches97.6% at-0.78 *** nanosized Bi2O3as the precursor can further reduce the primary particle sizes of the resulting Bi,leading to a significantly increased formate selectivity at relatively low *** high catalytic activity of nanostructured Bi is attributable to the ultrafine and interconnected Bi nanoparticles in the nanoporous structure,which exposes abundant active sites for CO_(2) electrocatalytic reduction.

关键词： bismuth carbon dioxide electrocatalysis formate solid electroreduction

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Effects of acid deposition control in China:a review based on responses of subtropical forests

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 115-126页

作者： Danni Xie Xiaodong Ge Lei Duan jan Mulder School of Land Engineering Chang’an UniversityXi’an 710064China State Key Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesBox 5003NO-1432ÅsNorway

For many decades,acid deposition used to pose a significant regional air pollution challenge in *** substantial emission control of anthropogenically derived sulfur and nitrogen containing gasses,both sulfur and nitrogen deposition,as well as the acid rain-affected area,have significantly decreased compared to their peak ***,particularly in the humid subtropics,are sensitive to acid deposition,as evidenced by soil acidification,sulfate and nitrate leaching in stream water,and elevated soil nitrous oxide *** in the total deposition of sulfur and nitrogen,caused a significant decline in sulfate and nitrate leaching from subtropical forest and subsequently in sulfate and nitrate concentrations in stream water,although there was about a 5-year *** delay may be attributed to the desorption of accumulated sulfate and continued elevated mineralization of accumulated nitrogen *** of nitrous oxide,a potent greenhouse gas,also declined in nitrogen-saturated subtropical forest soils,as soil water nitrate concentration ***,subtropical forests in China suffering from elevated acid deposition have begun to ***,the current levels of sulfur and nitrogen deposition continue to exceed the critical loads,i.e.,the assigned threshold levels in accordance with emission control policies,in more than 10%of the country’s land area,respectively,indicating remaining risks of acidification and ***,further emission reductions are urgently needed,also because they will help achieving goals related to air quality and nitrous oxide emissions.

关键词： Acidification Critical load Nitrous oxide Surface water chemistry Recovery

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Weak influence of natural vegetation in urban green spaces compared to agricultural ecosystems on House Martin populations:Insights from nationwide citizen science data in the Czech Republic

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Avian Research 2024年第2期15卷 139-146页

作者： Denisa Dvorakova jan Sipos Josef Suchomel Department of Zoology FisheriesHydrobiology and ApicultureMendel University in BrnoZemedelska 161300BrnoCzech Republic

The House Martin(Delichon urbicum)is a common farmland bird species in the European landscape,yet its population numbers are currently in ***,it is not yet sufficiently explained why this long-term decline *** fill this gap in our knowledge,we investigated how land cover composition affects the abundance of House Martins on the landscape scale by using nationwide citizen science *** a generalised linear mixed-effect model(GLMM),we evaluated 12,094 records from the Czech Republic spanning *** analysis underscores the significance of land cover type in shaping House Martin *** specifically,our results indicate that within agricultural land covers“naturally managed arable lands”exhibited significant positive effect,while forests,orchards,and vineyards were deemed less favourable for House Martin *** urban land covers,we found a clear distinction in the impact on House Martin populations,with a positive effect observed in urban infrastructure,development areas,and post-industrial sites(i.e.,UrbanAreas),while an indifferent impact was noted within urban green spaces and landscaped areas(i.e.,GreenUrban).Notably,our findings suggest that the simple spatial,age,and species structure typical of forests in Europe,and similarly,the uniform structure of parks and gardens,may be responsible for the decline in the abundance of the House *** advocate for the preservation or enhancement of urban greenery,expansion of natural vegetation in rural areas and adoption of ecological management practices in orchards and vineyards to mitigate further declines in House Martin populations.

关键词： Citizen science Habitat preferences House Martin Species distribution Urban and suburban landscape

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