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Interplay of transport processes and interfacial chemistry affecting chromium reduction and reoxidation with iron and manganese

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Frontiers of Environmental Science & Engineering 2020年第5期14卷 55-63页

作者： Chao Pan Daniel Giammar Department of Energy Environmentaland Chemical EngineeringWashington University in St.LouisSt.LouisMO 63130USA Present affiliation:Glenn *** Institute Physical&Life SciencesLawrence Livermore National LaboratoryLivermoreCA 94550USA

Hexavalent chromium(Cr(Ⅵ))is a water-soluble pollutant in soil and groundwater,the mobility,bioavailability,and toxicity of which can be controlled by transforming to less mobile and more environmentally benign Cr(Ⅲ)by ways of *** review focused on recent advances in identifying the reaction pathways,kinetics,and products of iron-based techniques for Cr(Ⅵ)*** also examines new information regarding remobilization of Cr(Ⅲ)in the existence of complexing ligands and manganese(Mn)of different oxidation states.A range of iron-based techniques can remove Cr(Ⅵ)from water by adsorption or reduction-coprecipitation ***,the success of a chromium treatment or remediation strategy requires the stability of the Cr(Ⅲ)-containing solids with respect to solubilization or reoxidation in the settings they are *** is ubiquitous in aquatic and terrestrial environments,and the redox cycling of manganese may greatly influence the fate,transport,and distribution of *** of redox reactions of chromium,iron,and manganese involves reaction pathways not only in the aqueous phase but also at solid-aqueous *** provide a quantitative understanding of these processes,it is essential to develop mechanistically based kinetic and transport *** research should be made on iron-based treatment of Cr(Ⅵ)-contaminated water and soils and the stability of the subsequently produced Cr(Ⅲ)-containing solids at environmentally relevant conditions,which will support improved predictions of chromium's environmental fate and transport and aid in decision-making for remediation and treatment of Cr contamination.

关键词： Chromium(Ⅵ)contamination Redox reaction Iron oxide Manganese oxide Modeling

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Phylogenetic Diversity of the Bacillu spumilus Group and the Marine Ecotype Revealed by Multilocus Sequence Analysis

Phylogenetic Diversity of the Bacillu spumilus Group and the...

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福建省海洋学会2014年学术年会暨福建省科协第十四届学术年会

作者： Yang Liu Qiliang Lai Chunming Dong Fengqin Sun Liping Wang Guangyu Li Zongze Shao Key laboratory of Marine Genetic Resources-State Key laboratory Breeding Base Third Institute of Oceanography of State Oceanic Administration Fujian Provincial Key Laboratory of Marine Genetic Resources

Bacteria closely related to Bacilluspumilus cannot be distinguished from such other species as B. safensis, B. stratosphericus, B. altitudinis and B. aerophilus simply by 16 S r RNA gene sequence. In this report, 76 marine strainswere subjected to phylogenetic analysis based on 7housekeeping genes to understand the phylogeny and biography in comparison with other origins. A phylogenetic tree based on the7 housekeeping genes concatenated in the order of gyr B-rpo B-pyc A-pyr E-mut L-aro E-trp Bwas constructed and compared with trees based on the single genes. All these trees exhibited a similar topology structure with small variations. Our 79 strains were divided into 6 groups from A to F;Group A was the largest and contained49 strains close to B. *** additional two large groups were presented by B. safensis and B. altitudinis. Among the housekeeping genes, gyr B and pyr E showed comparatively better resolution power and may serve as molecular markers to distinguish these closely related strains. Furthermore, arecombinant phylogenetic tree based on the gyr B gene and containing 73 terrestrial and our isolates was constructed to detect the relationship between marine and other sources. The tree clearly showed that the bacteria of marine origin were clustered together in all the large *** contrast, the cluster belonging to B. safensis was mainly composed of bacteriaof terrestrial origin. Interestingly, nearly all the marine isolates were at the top of the tree, indicating the possibility of the recent divergence of this bacterial group in marine *** conclude that B. altitudinis bacteria are the most widely spread of the B. pumilus group in marine environments. In summary, this report provides the first evidence regarding the systematic evolution of this bacterial group, and knowledge of their phylogenetic diversity will help in theunderstanding of theirecological role and distribution in marine environments.

关键词： Bacilluspumilus Bacillusaltitudinis Bacillussafensis MLSA diversity marine environments

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Plant carbon substrate supply regulated soil nitrogen dynamics in a tallgrass prairie in the Great Plains, USA: results of a clipping and shading experiment

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Journal of Plant Ecology 2011年第4期4卷 228-235页

作者： Xiaoli Cheng Yiqi Luo Bo Su Shiqiang Wan Dafeng Hui Quanfa Zhang Key laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Gardenthe Chinese Academy of SciencesWuhan 430074People’s Republic of China Department of Botany and Microbiology University of Oklahoma770 Van Vleet OvalNormanOK 73019USA laboratory of Quantitative Vegetation Ecology Institute of BotanyThe Chinese Academy of SciencesXiangshanBeijing 100093People’s Republic of China Department of Biological Sciences Tennessee State UniversityNashvilleTN 37209USA

Land use management affects plant carbon(C)supply and soil environments and hence alters soil nitrogen(N)dynamics,with consequent feedbacks to terrestrial ecosystem *** objective of this study was to better identify mechanisms by which land-use management(clipping and shading)regulates soil N in a tallgrass prairie,OK,*** We conducted 1-year clipping and shading experiment to investigate the effects of changes in land-use management(soil microclimates,plant C substrate supply and microbial activity)on soil inorganic N(NH_(4)^(+)-N and NO_(3)^(-)-N),net N mineralization and nitrification in a tallgrass *** Findings Land-use management through clipping and/or shading significantly increased annual mean inorganic N,possibly due to lowered plant N uptake and decreased microbial N immobilization into biomass *** significantly increased annual mean mineralization rates(P<0.05).Clipping slightly decreased annual mean N nitrification rates whereas shading significantly increased annual mean N nitrification *** microclimate significantly explained 36%of the variation in NO_(3)^(-)-N concentrations(P=0.004).However,soil respiration,a predictor of plant C substrate supply and microbial activity,was negatively correlated with NH_(4)^(+)-N concentrations(P=0.0009),net N mineralization(P=0.0037)and nitrification rates(P=0.0028)across *** results suggest that change in C substrate supply andmicrobial activity under clipping and/or shading is a critical control on NH_(4)^(+)-N,net N mineralization and nitrification rates,whereas clipping and shading-induced soil microclimate change can be important for NO_(3)^(-)-N variation in the tallgrass prairie.

关键词： plant Csubstratesupply N mineralization N nitrification soil microclimate soil respiration

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Plastid phylogenomics provides new insights into the systematics,diversification,and biogeography of Cymbidium(Orchidaceae)

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Plant Diversity 2024年第4期46卷 448-461页

作者： Hai-Yao Chen Zhi-Rong Zhang Xin Yao Ji-Dong Ya Xiao-Hua Jin Lin Wang Lu Lu De-Zhu Li Jun-Bo Yang Wen-Bin Yu Center for Integrative Conservation&Yunnan Key laboratory for the Conservation of Tropical Rainforests and Asian Elephants Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Huairou DistrictBeijing 101408China Plant Germplasm and Genomics Center Germplasm Bank of Wild SpeciesKunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China State Key laboratory of Plant Diversity and Specility Crops Institute of BotanyChinese Academy of SciencesHaidian DistrictBeijing 100093China School of Pharmaceutical Sciences Yunnan Key Laboratory of Pharmacology for Natural Productsand Yunnan College of Modern Biomedical IndustryKunming Medical UniversityKunmingYunnan 650500China Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesYezinNay Pyi Taw 05282Myanmar

Cymbidium(Orchidaceae:Epidendroideae),with around 60 species,is widely-distributed across Southeast Asia,providing a nice system for studying the processes that underlie patterns of biodiversity in the ***,phylogenetic relationships of Cymbidium have not been well resolved,hampering investigations of species diversification and the biogeographical history of this *** this study,we construct a plastome phylogeny of 56 Cymbidium species,with four well-resolved major clades,which provides a framework for biogeographical and diversification rate *** dating and biogeographical analyses show that Cymbidium likely originated in the region spanning northern IndoBurma to the eastern Himalayas during the early Miocene(~21.10 Ma).It then rapidly diversified into four major clades in East Asia within approximately a million years during the middle *** *** to the adjacent regions(Borneo,Philippines,and Sulawesi)primarily occurred during the Pliocene-Pleistocene *** analyses indicate that the net diversification rate of Cymbidium has decreased since its origin,and is positively associated with changes in temperature and monsoon *** hydrothermal conditions brought by monsoon intensification in the early Miocene possibly contributed to the initial rapid diversification,after which the net diversification rate was reduced with the cooling climate after the middle *** transition from epiphytic to terrestrial habits may have enabled adaptation to cooler environments and colonization of northern niches,yet without a significant effect on diversification *** study provides new insights into how monsoon activity and temperature changes affected the diversification dynamics of plants in Southeast Asia.

关键词： Cymbidium East Asia Asian monsoons Climate change Biogeographical patterns

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Geochemistry of Middle Holocene Sediments from South Yellow Sea: Implications to Provenance and Climate Change

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Journal of Earth Science 2016年第5期27卷 751-762页

作者： Xiaoxia Lii Gerard J. M. Versteegh Jinming Song Xuegang Li Huamao Yuan Ning Li Faculty of Marine Sciences China University of Geosciences State Key laboratory of Biogeology and Environmental Geology China University of Geosciences Heisenberg Group on Marine Kerogen Center for Marine Environmental Sciences (MARUM) Bremen University Institute of Oceanology Chinese Academy of Sciences

From a large number of case studies on terrestrial deposits we know that Late Holocene climate fluctuations have an important impact on the terrestrial environments. However, it is hitherto not clear how the marine sediments can be used to shed light on the environment and climate change of the catchment. To provide such insight, we used the major element, trace element and rare earth element（REE） compositions in the southern Yellow Sea（SYS） sediments to reconstruct the changes in weathering and erosion of their source regions. The sediments originate predominantly from the upper crust of East China and are transported into the basin especially by the Yellow River（Huanghe） and to a lesser extent by the Yangtze River（Changjiang）. The chemical index of alteration（CIA; 53.7–59.7） suggests low chemical weathering of the source rocks since the Middle Holocene. This is consistent with the relatively cool and arid climate in North China after the Holocene Megathermal. Comparison of element ratios, including Al/Ca, K/Ca, Al/Na, K/Na, Rb/Sr, Li/Ba and the CIA shows that we can use the latter as a robust proxy for climate change. The CIA-based mean annual precipitation and mean annual temperature show a series of climate fluctuations in the catchment. A relatively warm and humid Period I（5.3–2.9 cal. ka BP）, a relatively cool and dry Period II（2.9–0.9 cal. ka BP） and an increasingly cool and dry Period III（0.9–0.3 cal. ka BP）. These periods can be linked to climate intervals recognized elsewhere.

关键词： geochemical composition elemental ratio climate change provenance South YellowSea sediment.

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Mixing Deposition of Upper Carboniferous in Jiangshan,Zhejiang Province and its Tectonic Significance

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Acta Geologica Sinica(English Edition) 2010年第2期84卷 269-279页

作者： GUO Fusheng ZHU Zhijun HOU Zengqian YAN Zhaobin GUO Guolin East China Institute of Technology Fuzhou Jiangxi 344000 China Key laboratory of Nuclear Resources and Environment Ministry of Education Nanchang Jiangxi 330013 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

The Outangdi Formation in Jiangshan, Zhejiang, is the mixing deposit of terrigenous clastics and carbonates in Weiningian of the late Carboniferous. The mixing deposits include interbeddings, which constitute a series of alternated clastic and carbonate beds and mixing within the same bed which forms ＂hunji rock＂. The Outangdi Formation has the features of intercalated marine and terrestrial deposits with the progradational sequences, which are lower fine and upper coarse sedimentary granularity in the section. Hunji rock is formed in a seashore environment. It is a mixed carbonate sediment found in beaches or tideland facies with quartz sand taken from a bayou or beach by coastwise flow and circumfluence. There are two kinds of hunji sequences：（1） interbeds of sandstone and carbonate rock in seashore environments; and （2） interbeds of clastics in river facies and carbonate rock in ocean facies. It is indicated that mixing depositions belong to ＂facies mixing＂, affected mainly by regional tectonic uplift, rise of the global sea level, and the dynamics of water medium in the basin. Regional sea level periodic changes and progradational sequences probably resulted from the intense uplift of the old land called Cathaysia. The classification and name of mixed sediments are also discussed in the present study. Interbeds and alternated beds of clastic and carbonate beds are named ＂hunji sequence＂, a new genetic term. It is suggested that hunji rock means a special sediment event of mixing terrigenous clastics and carbonates instead of a name of a specific rock.

关键词： mixing deposits hunji rock hunji sequence tectonic uplift Carboniferous Jiangshan Zhejiang

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Wet deposition and scavenging ratio of air pollutants during an extreme rainstorm in the North China Plain

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Atmospheric and Oceanic Science Letters 2017年第5期10卷 348-353页

作者： Pan Yue-Peng Zhu Xia-Ying Tian Shi-Li Wang Li-Li Zhang Guo-Zhong Zhou Yan-Bo Xu Peng Hu Bo Wang Yue-Si State Key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC) Institute of Atmospheric Physics ChineseAcademy of Sciences Beijing China National Climate Center China Meteorological Administration Beijing China

Atmospheric wet deposition plays an important role in the supply of nutrients and toxic substances to terrestrial and aquatic environments. Although long-term（e.g. annual, multi-year） wet deposition is recorded well, pronounced and short-term changes in precipitation chemistry are less well investigated. In the present study, the precipitation chemistry and scavenging ratio of air pollutants were observed during an extreme torrential rain event（325.6 mm at the observation site） that occurred over 19–21 July 2016 in the North China Plain（NCP）. The scavenging ratio of particles showed a similar spatial distribution to that of the precipitation amount in the NCP, indicating the efficient removal of particulate matter due to the large amount and precipitation intensity of the storm. In addition, the scavenging ratio of water soluble ions was larger than that of organics and gaseous pollutants such as SO_2 and NO_2, likely due to their differences in water ***, raindrops incorporated more aerosol sulfate than gaseous compounds. Due to the heavy precipitation amount, almost all species in rainwater during this storm showed their lowest concentration but the highest flux compared with other rain events, indicating an important role played by this storm in terms of the substances received by the terrestrial and marine ecosystems of the region. However, the contribution of this storm to the annual chemical flux was lower than that of precipitation amount, indicating that the atmospheric compounds were scavenged below-cloud first and were then diluted by the cloud/rainwater. Future studies are needed in the context of the occurrence of extreme rainfall events in the NCP from the perspective of climate variability.

关键词： Extreme precipitation event rain chemistry wet deposition

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嗜热和非嗜热Crenarchaeota的生物多样性及演化意义

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高校地质学报 2005年第2期11卷 207-216页

作者：黄志勇王意敏张传伦 Savannah River Ecology laboratory University of Georgia Aiken SC 298032 USA

Crenarchaeota,Euryarchaeata和Korarchaeota组成古菌中3个领域。Euryarchaeota是原核生物中重要的种群,得到了很好的研究,而Crenarchaeota和Korarchaeota直到最近才逐渐受到关注。古菌的生态和演化研究都属于Crenarchaeota领域。一个很重要的观点就是Crenarchaeota的所有独立种群都是极端嗜热的,非嗜热Crenarchaeota目前为止还没有分离出来。嗜热Crenarchaeota主要是在深海热烟囱和陆地热泉中发现的,特征是高温(>80℃)和低pH值(<6)。多种嗜热Crenarchaeota化能自养可以利用还原性无机化合物,例如H2和还原性硫。这个特性连同生命树群的深入分支说明生命最后共同的祖先可能是在热液体系中的嗜热自养生物。非嗜热Crenarchaeota和嗜热Crenarchaeota有很近似的系统关系。尽管一般情况下非嗜热Crenarchaeota是不可以培养的,但是其对敞开体系海相、陆相土壤、湖泊和地下的中低温环境的适应性日益增强。这主要取决于独立培养分子学技术的发展,例如16SrRNA基因序列。此外,海洋和土壤中非嗜热Crenarchaeota的研究还表明,非嗜热Crenarchaeota确定组成在碳循环的生物地球化学循环中起着非常重要的作用。

关键词：嗜热非嗜热 Crenarchaeota 生物演化生物多样性

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Selective scission of glucose molecule by a Pd-modulated Co-based catalyst for efficient CO_(2)reduction under mild conditions

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Science Bulletin 2024年第19期69卷 3055-3065页

作者： Peidong Zhu Jiacong Li Yang Yang Heng Zhong Fangming Jin School of Environmental Science and Engineering State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China Shanghai Key laboratory of Hydrogen Science&Center of Hydrogen Science Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Combining terrestrial biomass as the reductant with submarine-type hydrothermal environments for CO_(2)reduction represents a possible approach for novel energy production systems that sustainably circulate ***,increasing the reductive power of biomass is the main limitation of this potential ***,we demonstrate that Co-doped with small amounts of Pd enhances the reduction of CO_(2)by selectively producing an active intermediate from *** catalytic reaction utilized glucose as a reductant to achieve high formate production efficiency(458.6 g kg^(-1))with nearly 100%selectivity with 7.5 wt%Pd1Co_(20)/γ–Al_(2)O_(3)at a moderate temperature of 225℃.The regulation of the electronic structure of the catalytic Co surface by the dopant Pd plays a key role in promoting the C–C bond cleavage of glucose and hydrogen transfer for CO_(2)*** findings presented here indicate that biomass can serve as the hydrogen source for CO_(2)reduction and provide insight into the potential utilization of CO_(2)in sustainable industrial applications.

关键词： Pd-Co catalyst CO_(2) Reduction Glucose Formate

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Organic carbon and nitrogen isotopes in surface sediments from the western Arctic Ocean and their implications for sedimentary environments

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Acta Oceanologica Sinica 2006年第5期25卷 39-54页

作者： CHEN Zhihua SHI Xuefa CAI Deling HAN Yibing YANG Zuosheng Ocean University of China Qingdao 266003 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Key laboratory of Marine Sedimentology ＆ Environmental Geology of State Oceanic Administration First Institute of Oceano-graph State Oceanic AdministrationQingdao 266061 China

Surface sediments from the Chukchi Sea and adjacent arctic deep sea were investigated for organic carbon and nitrogen isotopes （in δ13Corg and δ15Norg） as well as biogeni＇c silica （BSiO2）. δ13Corg and δ15Norg values of surface sediments in the study area fall between the end-member values of marine and terrestrial organic matter from the surrounding lands and seas, their variations reflect the changes of marine productivity and terrestrial supply in the study area. BSiO2 shows a similar distribution pattern with δ13Corg and δ15Norg, and can be used as an indicator of marine productivity. In the central-west Chukchi Sea and the Chukchi Rise, sediments have higher δ13Corg, δ15Norg and BSiO2 values, indicating the region has high marine productivity influenced by the nutrient-rich branches of the Pacific waters. In the coastal zone off northwestern Alaska, δ13Corg and δ15Norg values become lighter, indicating a weakening marine productivity and an increasing terrigenous supply due to the effects of the least nutrient-rich branch of the Pacific waters. In the north and the northeast of the study area （including the Chukchi Plateau, the Canada Basin and the Beaufort shelf）, δ13Corg, δ15Norg and BSiO2 have the lowest values, and the terrigenous organic matter becomes dominant in surface sediments because this region has the longest ice-covered duration, the least nutrient-rich seawater and the increasing supply of terrestrial materials from the Mackenzie River and the northern Alaska under the action of the clockwise Beaufort gyre. Because the subarctic Pacific waters are continuously discharged into the central basin of the Arctic Ocean through the study area, the nutrient pool in the Chukchi Sea can be considered as a typical open system, the ratio of δ15Norg to BSiO2 content show some tracers that the level of nutrient utilization is contrary to nutrient supply and marine productivity formed in seawater.

关键词： western Arctic Ocean surface sediments organic carbon and nitrogen isotopes biogenic silica

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