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3D-Printed MOF Monoliths:Fabrication Strategies and Environmental Applications
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作者 Hossein Molavi Kamyar Mirzaei +4 位作者 Mahdi Barjasteh Seyed Yahya Rahnamaee Somayeh Saeedi Aliakbar Hassanpouryouzband Mashallah Rezakazemi 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期358-405,共48页
Metal-organic frameworks(MOFs)have been extensively considered as one of the most promising types of porous and crystalline organic-inorganic materials,thanks to their large specific surface area,high porosity,tailora... Metal-organic frameworks(MOFs)have been extensively considered as one of the most promising types of porous and crystalline organic-inorganic materials,thanks to their large specific surface area,high porosity,tailorable structures and compositions,diverse functionalities,and well-controlled pore/size distribution.However,most developed MOFs are in powder forms,which still have some technical challenges,including abrasion,dustiness,low packing densities,clogging,mass/heat transfer limitation,environmental pollution,and mechanical instability during the packing process,that restrict their applicability in industrial applications.Therefore,in recent years,attention has focused on techniques to convert MOF powders into macroscopic materials like beads,membranes,monoliths,gel/sponges,and nanofibers to overcome these challenges.Three-dimensional(3D)printing technology has achieved much interest because it can produce many high-resolution macroscopic frameworks with complex shapes and geometries from digital models.Therefore,this review summarizes the combination of different 3D printing strategies with MOFs and MOF-based materials for fabricating 3D-printed MOF monoliths and their environmental applications,emphasizing water treatment and gas adsorption/separation applications.Herein,the various strategies for the fabrication of 3D-printed MOF monoliths,such as direct ink writing,seed-assisted in-situ growth,coordination replication from solid precursors,matrix incorporation,selective laser sintering,and digital light processing,are described with the relevant examples.Finally,future directions and challenges of 3D-printed MOF monoliths are also presented to better plan future trajectories in the shaping of MOF materials with improved control over the structure,composition,and textural properties of 3D-printed MOF monoliths. 展开更多
关键词 MOFS 3D-printing Environmental remediation SHAPING MONOLITHS
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Geochronological and geochemical constraints on the granitic gneiss in the Huozhou Complex: implications for the tectonic evolution of the Trans-North China Orogen 被引量:2
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作者 Chong Peng Haiyan Liu +3 位作者 Ruiying Zhang Cremilda Samuel Jofrisse Linfu Xue Baozhi Pan 《Acta Geochimica》 EI CAS CSCD 2023年第1期153-181,共29页
The Trans-North China Orogen is a major Neoarchean Paleoproterozoic collisional orogenic belt above the North China Craton, formed due to prolonged and complex processes. Even though many NeoarcheanPaleoproterozoic ma... The Trans-North China Orogen is a major Neoarchean Paleoproterozoic collisional orogenic belt above the North China Craton, formed due to prolonged and complex processes. Even though many NeoarcheanPaleoproterozoic magmatic and metamorphic activities have been reported, due to the Huozhou Complex’s small outcropping range, little attention has been paid to the origin of various igneous rocks of the Huozhou Complex in the center of the Trans-North China Orogen. The Huozhou Complex, located south of the Luè liang, Wutai, and Hengshan complexes, is an important window into the Early Precambrian structure and evolution of the North China Craton. Its magma and metamorphism are crucial to understanding the development of the structural evolution of the Trans-North China Orogen. The Huozhou metamorphic complex area exposes a range of Precambrian metamorphic rocks, among which the most extensively dispersed is felsic biotite plagioclase gneiss. In this study comprehensive geological field survey, micropetrology,chronology, geochemistry, and Hf isotope analysis were carried out for the Qinggangping and Anziping gneiss in the north of the Huozhou Complex. The results show that the magmatic zircon age of the Qinggangping gneiss is2196 ± 14 Ma, and its protolith is I-type granite, formed by partial melting of igneous rocks in the absence of weathering. Its source is mainly the juvenile crust from depleted mantle dating 2431–2719 Ma, with a small amount of mantle-derived material. The Anziping gneiss has a metamorphic zircon age of 1931 ± 13 Ma with an S-type granite protolith belonging to peraluminous granite.The Anziping gneiss is formed by recycling pre-existing crustal components at 2613–2848 Ma. A minor quantity of mantle-derived magma is also introduced to the crust simultaneously. The samples of Qinggangping gneiss and Anziping gneiss show the characteristics of obvious negative Nb, Ti, and P elements in the spider diagram of primitive mantle standardization. This implies that the rocks have the characteristics of magmatic rocks in an island arc or subduction environment, which could have formed in the tectonic environment of the continental margin arc. 展开更多
关键词 Zircon U–Pb dating Geochemistry Huozhou complex Trans-North China orogen Biotite plagioclase gneiss North China craton
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2.7-Ga-old mafic dike in the Trans-North China Orogen of the North China Craton and its tectonic significance
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作者 Haiyan Liu Chong Peng 《Acta Geochimica》 EI CAS CSCD 2023年第6期1124-1129,共6页
We studied an Archean mafic dike in the TransNorth China Orogen of the North China Craton, which has a magmatic age of 2701 ± 83 Ma and is currently the oldest mafic dike in the North China Craton. Such an old di... We studied an Archean mafic dike in the TransNorth China Orogen of the North China Craton, which has a magmatic age of 2701 ± 83 Ma and is currently the oldest mafic dike in the North China Craton. Such an old dike is extremely rare in the world. The presence of mafic dikes indicates that the North China Craton was in a tensional tectonic environment at 2.7 Ga. Geochemical characteristics reveal that this mafic dike belongs to continental tholeiitic basalt. Results from Hf isotope analysis reveal that the mafic dike originates from a depleted mantle. The plate assembly in the North China landmass was realized during the Archean era(2.7 Ga), and a thick and stable continental crust was formed. Therefore, the first cratonization of the North China Craton was completed before 2.7 Ga. The intrusion of the 2.7-Ga-old mafic dike from the deep lithospheric mantle of the continent indicates that the North China Craton has undergone a period of extensional tectonic activity. This event marks a significant extensional event that occurred after the cratonization of the North China Craton. 展开更多
关键词 ARCHEAN Mafic dike Trans-North China Orogen North China Craton Hf CRATONIZATION
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Two species of microcracks 被引量:8
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作者 Stuart Crampin 高原 《Applied Geophysics》 SCIE CSCD 2014年第1期1-8,115,共9页
We identify two interrelated but independent species of microcracks with different origins and different distributions. One species is the classic high-stress microcracks identified in laboratory stress-cells associat... We identify two interrelated but independent species of microcracks with different origins and different distributions. One species is the classic high-stress microcracks identified in laboratory stress-cells associated with acoustic emissions as microcracks open with increasing stress. The other species is the low-stress distributions of closely-spaced stress-aligned fluid-saturated microcracks that observations of shear-wave splitting(SWS) demonstrate pervade almost all in situ rocks in the upper crust, the lower crust, and the uppermost 400 km of the mantle. On some occasions these two sets of microcracks may be interrelated and similar(hence ‘species') but they typically have fundamentally-different properties, different distributions, and different implications. The importance for hydrocarbon exploration and recovery is that SWS in hydrocarbon reservoirs monitors crack alignments and preferred directions of fluid-flow. The importance for earthquake seismology is that SWS above small earthquakes monitors the effects of increasing stress on the pervasive low-stress microcrack distributions so that stress-accumulation before, possibly distant, earthquakes can be recognised and impending earthquakes stress-forecast. 展开更多
关键词 crack-induced anisotropy fluid-saturate microcracks shearwave splitting stressforecasting earthquakes two species of microcracks
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The Role of Stationary and Transient Planetary Waves in the Maintenance of Stratospheric Polar Vortex Regimes in Northern Hemisphere Winter 被引量:4
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作者 李倩 Hans-F.GRAF 崔雪锋 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第1期187-194,共8页
Using 1958-2002 NCEPNCAR reanalysis data, we investigate stationary and transient planetary wave propagation and its role in wave-mean flow interaction which influences the state of the polar vortex (PV) in the stra... Using 1958-2002 NCEPNCAR reanalysis data, we investigate stationary and transient planetary wave propagation and its role in wave-mean flow interaction which influences the state of the polar vortex (PV) in the stratosphere in Northern Hemisphere (NH) winter. This is done by analyzing the Eliassen-Palm (E-P) flux and its divergence. We find that the stationary and transient waves propagate upward and equatorward in NH winter, with stronger upward propagation of stationary waves from the troposphere to the stratosphere, and stronger equatorward propagation of transient waves from mid-latitudes to the subtropics in the troposphere. Stationary waves exhibit more upward propagation in the polar stratosphere during the weak polar vortex regime (WVR) than during the strong polar vortex regime (SVR). On the other hand, transient waves have more upward propagation during SVR than during WVR in the subpolar stratosphere, with a domain of low frequency waves. With different paths of upward propagation, both stationary and transient waves contribute to the maintenance of the observed stratospheric PV regimes in NH winter. 展开更多
关键词 stratospheric polar vortex planetary waves STATIONARY transient
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Analysis of Differences in Productivity,Profitability and Soil Fertility Between Organic and Conventional Cropping Systems in the Tropics and Sub-tropics 被引量:1
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作者 Te Pas C M Rees R M 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第10期2299-2310,共12页
Organic farming aims to stimulate soil fertility by avoiding the use of synthetic fertiliser inputs, relying instead on locally available natural resources. It is regarded by many as a sustainable alternative to conve... Organic farming aims to stimulate soil fertility by avoiding the use of synthetic fertiliser inputs, relying instead on locally available natural resources. It is regarded by many as a sustainable alternative to conventional fanning because it ensures higher biodiversity, restricts environmental pollution, prevents land degradation and is easy to apply for smallholder and subsistence farmers. Although widely practiced and studied in temperate regions, little is known about the potential overall benefits of organic farming in the tropics and subtropics. This paper addresses this gap by undertaking an analysis of the differences between organic and conventional agriculture in the tropics and sub-tropics based on an extensive literature review including 88 papers with 458 data pairs. The comparison is based on three main indicators: yield, gross margin and soil organic carbon (SOC). The differences between the organic and conventional systems for each of these main indicators is represented by the ratio of the value of the indicator in the organic system divided by the corresponding value in the conventional system. This was initially calculated for each data pair individually, and grouped by a variety of explanatory factors, such as precipitation, human development level, soil texture, crop type, organic input type, time after conversion and certification. The results demonstrate that under organic management, yields were on average 26% higher, gross margins 51% higher and soil organic carbon 53% higher than under conventional management. The highest yield increases in organic cropping systems were achieved in the least developed countries, in arid regions and on coarse soils. For gross margins, certification was the main reason for differences between organic and conventional systems. Certified farmers, mostly located in developed countries, receive significantly higher prices. Furthermore, organic farming in the driest regions results in higher profits than in other regions. Even though soil organic carbon was significantly higher overall under organic management, the results do not show significant differences when grouped by the explanatory factors. They do however suggest that the highest carbon sequestration potential occurs in systems that had a high level of inputs, in regions with 1000-1 500 mm of rainfall and on clayey soils. 展开更多
关键词 organic farming conventional fanning TROPICS SUBTROPICS carbon sequestration yield soil quality soil organic carbon
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A review of the New Geophysics:a new understanding of pre-fracturing deformation in the crack-critical crust with implications for hydrocarbon production 被引量:1
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作者 Stuart Crampin Yuan Gao 《Petroleum Science》 SCIE CAS CSCD 2008年第1期1-12,共12页
This paper reviews a new understanding of shear-wave splitting (seismic-birefringence) that is a fundamental revision of conventional fluid-rock deformation. It is a New Geophysics with implications for almost all s... This paper reviews a new understanding of shear-wave splitting (seismic-birefringence) that is a fundamental revision of conventional fluid-rock deformation. It is a New Geophysics with implications for almost all solid-earth geosciences, including hydrocarbon exploration and production, and earthquake forecasting. Widespread observations of shear-wave splitting show that deformation in in situ rocks is controlled by stress-aligned fluid-saturated grain-boundary cracks and preferentially orientated pores and pore-throats pervasive in almost all igneous, metamorphic, and sedimentary rocks in the Earth's crust. These fluid-saturated microcracks are the most compliant elements of the rock-mass and control rock deformation. The degree of splitting shows that the microcracks in almost all rocks are so closely spaced that they verge on fracture-criticality and failure by fracturing, and are critical systems with the “butterfly wing's” sensitivity of all critical systems. As a result of this crack-criticality, evolution of fluid-saturated stress-aligned microcracked rock under changing conditions can be modelled with anisotropic poroelasticity (APE). Consequently, low-level deformation can be: monitored with shear-wave splitting; future behaviour calculated with APE; future behaviour predicted with APE, if the change in conditions can be quantified; and in principle, future behaviour controlled by feed-back. This paper reviews our current understanding of the New Geophysics of low-level pre-fracturing deformation. 展开更多
关键词 Crack anisotropy New Geophysics pre-fracturing deformation seismic birefringence shear-wave splitting
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Non-seismic geophysical analysis of potential geothermal resources in the Longgang Block,Northeast China 被引量:1
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作者 HaiYan Liu Chong Peng +3 位作者 LinFu Xue WenQing Li ChunHui Xu Cremilda Samuel Jofrisse 《Earth and Planetary Physics》 EI CSCD 2022年第6期576-591,共16页
Although geothermal energy has many clear advantages,including its sustainability and environmentally friendly nature,research into potential geothermal resources across the Longgang Block,Northeast China,has been lim... Although geothermal energy has many clear advantages,including its sustainability and environmentally friendly nature,research into potential geothermal resources across the Longgang Block,Northeast China,has been limited.Here we present the first analysis of the potential geothermal resources in this region that employs joint geological and non-seismic geophysical methods to identify target areas that may be economically viable.We acquire and analyze high-precision gravity,magnetic,and magnetotelluric sounding data,which are constrained using the petrophysical parameters of outcropping rocks across the Longgang Block,to conduct a comprehensive evaluation of the region’s deep geological structures and their geothermal resources potential,with a focus on identifying faults,rock masses,and thermal storage structures.We find that Archean granitic gneiss and Mesozoic rock masses in the deeper section of the Longgang Block possess weak gravity anomalies and high resistivities.We also identify thermal storage structures near these deeper geological units based on their extremely low resistivities.The data are used to infer the dip and depth of known or hidden faults,to constrain the spatial distribution of intrusive rock masses,and to determine the spatial distribution of subsurface thermal storage structures.The potential of the target areas for geothermal resources exploitation is divided into three grades based on contact depths between faults and thermal storage structures,and the scale of their thermal storage structures.Our results suggest that a joint non-seismic geophysical approach can be effective in locating and evaluating geothermal resources in complex geological settings. 展开更多
关键词 Longgang Block geothermal resources Anshan−Benxi area petrophysical parameters magnetotelluric sounding
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An Agent-Based Assessment of Land Use and Ecosystem Changes in Traditional Agricultural Landscape of Portugal 被引量:2
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作者 Lilibeth A.Acosta Mark D.A.Rounsevell +3 位作者 Martha Bakker Ann Van Doorn Montserrat Gomez-Delgado Marc Delgado 《Intelligent Information Management》 2014年第2期55-80,共26页
This paper presents an assessment of land use changes and their impacts on the ecosystem in the Montado, a traditional agricultural landscape of Portugal in response to global environmental change. The assessment uses... This paper presents an assessment of land use changes and their impacts on the ecosystem in the Montado, a traditional agricultural landscape of Portugal in response to global environmental change. The assessment uses an agent-based model (ABM) of the adaptive decisions of farmers to simulate the influence on future land use patterns of socio-economic attributes such as social relationships and farmer reliance on subsidies and biophysical constraints. The application and development of the ABM are supported empirically using three categories of input data: 1) farmer types based on a cluster analysis of socio-economic attributes;2) agricultural suitability based on regression analysis of historical land use maps and biophysical attributes;and 3) future trends in the economic and climatic environments based on the A1fi scenario of the Intergovernmental Panel on Climate Change. Model sensitivity and uncertainty analyses are carried out prior to the scenario analysis in order to verify the absence of systematic errors in the model structure. The results of the scenario analysis show that the area of Montado declines significantly by 2050, but it remains the dominant land use in the case study area, indicating some resilience to change. An important policy challenge arising from this assessment is how to encourage next generation of innovative farmers to conserve this traditional landscape for social and ecological values. 展开更多
关键词 ABANDONMENT Agent-Based Model Cluster Analysis Ecosystem and Biodiversity Land Use Change Logistic Regression PORTUGAL Scenario Analysis Traditional Agricultural Landscape
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Associations and mobility of uranium in soils near a depleted uranium (DU) weapons testing site, SW Scotland
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作者 Margaret C. Graham John G. Farmer +2 位作者 Ian W. Oliver Angus B. MacKenzie Robert M. Ellam 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期112-112,共1页
关键词 胶体 有机物质 凝胶 电泳法 超滤 土壤化学
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Development of a facility for analysis of natural ^(32)Si
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作者 Angus B. MacKenzie David C.W. Sanderson +3 位作者 Joseph Melone John G. Farmer Christoph Schnabel Helfrid Rossiter 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期199-200,共2页
关键词 年代学 沉积物 光电二极管 环境污染 放射性核素
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Impacts of Anthropogenic Forcings and El Nio on Chinese Extreme Temperatures
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作者 N. FREYCHET S. SPARROW +3 位作者 S. F. B. TETT M. J. MINETER G. C. HEGERL D. C. H. WALLOM 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第8期98-106,共9页
This study investigates the potential influences of anthropogenic forcings and natural variability on the risk of summer extreme temperatures over China. We use three multi-thousand-member ensemble simulations with di... This study investigates the potential influences of anthropogenic forcings and natural variability on the risk of summer extreme temperatures over China. We use three multi-thousand-member ensemble simulations with different forcings (with or without anthropogenic greenhouse gases and aerosol emissions) to evaluate the human impact, and with sea surface temperature patterns from three different years around the E1 Nino-Southern Oscillation (ENSO) 2015/16 event (years 2014, 2015 and 2016) to evaluate the impact of natural variability. A generalized extreme value (GEV) distribution is used to fit the ensemble results. Based on these model results, we find that, during the peak of ENSO (2015), daytime extreme tem- peratures axe smaller over the central China region compared to a normal year (2014). During 2016, the risk of nighttime extreme temperatures is largely increased over the eastern coastal region. Both anomalies are of the same magnitude as the anthropogenic influence. Thus, ENSO can amplify or counterbalance (at a regional and annual scale) anthropogenic effects on extreme summer temperatures over China. Changes are mainly due to changes in the GEV location parameter. Thus, anomalies are due to a shift in the distributions and not to a change in temperature variability. 展开更多
关键词 extreme temperatures ENSO anthropogenic impact climate risk
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Salvia ceratophylla L. from South of Jordan: new insights on chemical composition and biological activities
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作者 Mohammad Sanad Abu-Darwish Célia Cabral +10 位作者 Zulfigar Ali Mei Wang Shabana IKhan Melissa RJacob Surendra KJain Babu LTekwani Fazila Zulfiqar Ikhlas AKhan Hatem Taifour Lígia Salgueiro Thomas Efferth 《Natural Products and Bioprospecting》 CAS 2020年第5期307-316,共10页
In Jordan,Salvia ceratophylla L.is traditionally used in the treatment of cancer,microbial infections,and urinary disorders.This study aimed:(1)to chemically characterize S.ceratophylla essential oil(EO)from South Jor... In Jordan,Salvia ceratophylla L.is traditionally used in the treatment of cancer,microbial infections,and urinary disorders.This study aimed:(1)to chemically characterize S.ceratophylla essential oil(EO)from South Jordan,by gas chromatography(GC)and gas chromatography-mass spectrometry(GC-MS);and(2)to evaluate in vitro the cytotoxic,anti-inflammatory,and antiprotozoal activities of the EO,it’s predominant components,and the hexane(A),ethyl acetate(B),methanol(C)and crude-methanol extracts(D).The analysis revealed that the EO has 71 compounds,with linalool(54.8%)as main constitu-ent.Only the hexane extract(A)showed some cytotoxic activity against SK-MEL,KB,BT-549,SK-OV-3,LLC-PK1 and VERO cells lines with IC50 between 60 and>100μg/mL.The EO inhibited NO production(IC5090μg/mL)and NF-κB activity(IC5038μg/mL).The extracts A,B,and D inhibited NO production and NF-κB activity with IC50 between 32 and 150μg/mL.Linalool considerably inhibited NO production(IC5018μg/mL).The extracts tested did not exhibit antileish-manial activity.Regarding antitrypanosomal activity,the EO exhibited significant results with IC502.65μg/mL.In conclu-sion,Jordan S.ceratophylla EO represents a rich source of linalool and bears a promising therapeutic potential for further antitrypanosomal drug development. 展开更多
关键词 Lamiaceae Essential oil Chemical composition CYTOTOXICITY Anti-inflammatory activity Neglected diseases
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上拱力背景下正断裂剖面形态及极限应力状态研究 被引量:4
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作者 宋随宏 陈书平 何明宇 《地质力学学报》 CSCD 2012年第2期149-157,共9页
上拱力构造背景下形成的正断裂及断裂极限应力状态研究在构造解释和油气运移成藏中具有重要的意义。在抛物线型莫尔包络线理论的基础上,通过合理的假设和数学推导以及理论模拟,进一步探讨上拱力构造背景影响下形成的正断裂剖面形态和断... 上拱力构造背景下形成的正断裂及断裂极限应力状态研究在构造解释和油气运移成藏中具有重要的意义。在抛物线型莫尔包络线理论的基础上,通过合理的假设和数学推导以及理论模拟,进一步探讨上拱力构造背景影响下形成的正断裂剖面形态和断裂的极限应力状态,并定量给出函数表达式。研究结果表明,断裂在均质岩体中由浅到深,倾角从竖直开始由大变小,呈铲状断裂,而变化的速率只与地层物性有关,泥岩比砂岩变化快。断裂分布的深度与上拱力的大小成一次线性关系,上拱力越大,断裂分布越浅。砂泥岩互层地层中发育有典型的坡坪式正断裂。研究结果不仅与普遍认识相一致,而且可以进一步在实际应用中预测断裂的存在,定量解释断裂形态,求取上拱力和断裂极限应力状态。 展开更多
关键词 上拱力 正断裂形态 极限应力 断裂准则
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地震能够应力预测 被引量:2
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作者 Crampin Stuart Gao Yuan +1 位作者 王琼(译) 高原(校) 《国际地震动态》 2010年第7期7-11,共5页
1997年Geller等人曾发表"地震不能预报",因为在自组织临界系统中尺度不变性是普遍存在的,而地球正处于自组织临界状态中,在这种状态下小地震具有某种概率,如瀑布般触发大的地震事件。但是在物理上,只有对应其地震震级的应力... 1997年Geller等人曾发表"地震不能预报",因为在自组织临界系统中尺度不变性是普遍存在的,而地球正处于自组织临界状态中,在这种状态下小地震具有某种概率,如瀑布般触发大的地震事件。但是在物理上,只有对应其地震震级的应力能量得到有效释放,才能有大地震的发生。利用对这种应力的依赖性可以进行地震预测,方法就是利用剪切波分裂来监控即将发生地震的周围岩体的应力积累。这项技术可以说是成功的,但是由于假定的不可预报性,所以需要清晰的论证才能被普遍接受。雪崩也是自组织临界现象。近期通过二维球形素珠堆进行的雪崩实验观测表明,具有自组织临界性的自然物理现象是能够预报的,如雪崩、地震等。预报地震和雪崩的关键是监控母体介质,而不是即将发震的震源区。 展开更多
关键词 自组织 地震动力学 地震相互作用 预测与预报 地震各向异性 波的传播 动力学 地震构造
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The performance of nitrate-reducing Fe(Ⅱ)oxidation processes under variable initial Fe/N ratios:The fate of nitrogen and iron species 被引量:4
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作者 Boyi Cheng Yi Wang +1 位作者 Yumei Hua Kate V.Heal 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2021年第4期287-298,共12页
The Fe/N ratio is an important control on nitrate-reducing Fe(Ⅱ)oxidation processes that occur both in the aquatic environment and in wastewater treatment systems.The response of nitrate reduction,Fe oxidation,and mi... The Fe/N ratio is an important control on nitrate-reducing Fe(Ⅱ)oxidation processes that occur both in the aquatic environment and in wastewater treatment systems.The response of nitrate reduction,Fe oxidation,and mineral production to different initial Fe/N molar ratios in the presence of Paracoccus denitrificans was investigated in 132 h incubation experiments.A decrease in the nitrate reduction rate at 12 h occurred as the Fe/N ratio increased.Accumulated nitrite concentration at Fe/N ratios of 2–10 peaked at 12–84 h,and then decreased continuously to less than 0.1 mmol/L at the end of incubation.N_(2)O emission was promoted by high Fe/N ratios.Maximum production of N_(2) occurred at a Fe/N ratio of 6,in parallel with the highest mole proportion of N_(2) resulting from the reduction of nitrate(81.2%).XRD analysis and sequential extraction demonstrated that the main Fe minerals obtained from Fe(Ⅱ)oxidation were easily reducible oxides such as ferrihydrite(at Fe/N ratios of 1–2),and easily reducible oxides and reducible oxides(at Fe/N ratios of 3–10).The results suggest that Fe/N ratio potentially plays a critical role in regulating N_(2),N_(2)O emissions and Fe mineral formation in nitrate-reducing Fe(II)oxidation processes. 展开更多
关键词 DENITRIFICATION N_(2)O emission Fe(Ⅱ)oxidation Fe/N ratio Fe minerals
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Mapping mountain areas: learning from Global, European and Norwegian perspectives 被引量:3
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作者 Martin F.PRICE Tor ARNESEN +1 位作者 Erik GL?ERSEN Marc J.METZGER 《Journal of Mountain Science》 SCIE CSCD 2019年第1期1-15,共15页
Defining the spatial extent of mountain areas has long been a challenge. In the present century, the availability of digital elevation models(DEMs) incorporated into geographic information systems(GIS) has allowed the... Defining the spatial extent of mountain areas has long been a challenge. In the present century, the availability of digital elevation models(DEMs) incorporated into geographic information systems(GIS) has allowed the definition of mountain areas based on topographic and other criteria. This paper presents the various delineations of mountains that have been prepared at three scales – global, regional(Europe), and national – and explores the reasons and processes leading to these delineations, and how they have been used. A detailed case study is then presented for Norway. Overall, two types of approaches to mapping mountains have been taken: first, considering mountains per se, based on elevation and/or topography; second, considering them among other categories, e.g., landforms or biogeographical, environmental or landscape zones. All attempts to map mountain areas derive essentially from the objectives of those commissioning and/or undertaking the work; a unitary definition remains unlikely. 展开更多
关键词 MOUNTAINS MAPPING GEOGRAPHIC information systems EUROPE Norway TOPOGRAPHY
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Zinc Isotope Characteristics in the Biogeochemical Cycle as Revealed by Analysis of Suspended Particulate Matter(SPM) in Aha Lake and Hongfeng Lake, Guizhou, China 被引量:4
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作者 Lili Liang Cong-Qiang Liu +4 位作者 Xiangkun Zhu Bryne TNgwenya Zhongliang Wang Liuting Song Jin Li 《Journal of Earth Science》 SCIE CAS CSCD 2020年第1期126-140,共15页
Zn isotope is a useful tool for tracing biogeochemical processes as zinc plays important roles in the biogeochemistry of natural systems. However, the Zn isotope composition in the lake ecosystems has not been well ch... Zn isotope is a useful tool for tracing biogeochemical processes as zinc plays important roles in the biogeochemistry of natural systems. However, the Zn isotope composition in the lake ecosystems has not been well characterized. In order to resolve this problem, we investigate the Zn isotope compositions of suspended particulate matter(SPM) and biological samples collected from the Aha Lake and Hongfeng Lake, and their tributaries in summer and winter, aiming to explore the potential of this novel isotope system as a proxy for biogeochemical processes in aqueous environments. Concentration of dissolved Zn ranges from 0.65 to 5.06 μg/L and 0.74 to 12.04 μg/L for Aha Lake and Hongfeng Lake, respectively, while Zn(SPM) ranges from 0.18 to 0.70 mg/g and 0.24 to 0.75 mg/g for Aha Lake and Hongfeng Lake, respectively. The Zn isotope composition in SPM from Aha Lake and its main tributaries ranges from -0.18‰ to 0.27‰ and -0.17‰ to 0.46‰, respectively, and it varies from -0.29‰ to 0.26‰ and -0.04‰ to 0.48‰, respectively in Hongfeng Lake and its main tributaries, displaying a wider range in tributaries than lakes. These results imply that Zn isotope compositions are mainly affected by tributaries inputting into Aha Lake, while adsorption process by algae is the major factor for the Zn isotope composition in Hongfeng Lake, and ZnS precipitation leads to the light Zn isotope composition of SPM in summer. These data and results provide the basic information of the Zn isotope for the lake ecosystem, and promote the application of Zn isotope in biogeochemistry. 展开更多
关键词 Zn isotope SPM Aha Lake Hongfeng Lake TRIBUTARY
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Is environmental antimony a potential health problem? 被引量:1
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作者 John G. Farmer Joanna M. Cloy +2 位作者 Margaret C. Graham Angus B. MacKenzie Gordon T. Cook 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期68-69,共2页
关键词 环境污染 人体健康 有毒元素
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2009年9月印度尼西亚巴东地震 被引量:1
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作者 John McCloskey Dietrich Lange +5 位作者 Frederik Tilmann Suleyman S Nalbant Andrew F Bell Danny Hilman Natawidjaja Andreas Rietbrock 左玉玲 《国际地震动态》 2010年第8期14-17,共4页
2009年9月30日,印度尼西亚巴东市发生7.6级地震。之后,印度尼西亚又接连遭受了几次强震袭击,如2009年12月23日6.1级、2010年3月6日7.1级、2010年4月7日7.8级和2010年5月9日7.4级地震。2010年6月16日一天之内,印度尼西亚又接连发生了3次... 2009年9月30日,印度尼西亚巴东市发生7.6级地震。之后,印度尼西亚又接连遭受了几次强震袭击,如2009年12月23日6.1级、2010年3月6日7.1级、2010年4月7日7.8级和2010年5月9日7.4级地震。2010年6月16日一天之内,印度尼西亚又接连发生了3次地震,震级分别为6.3级、7.0级和6.3级。2010年2月,由John McCloskey领军的一个科学家团队就2009年9月巴东地震致函英国《自然—地球科学》杂志(Nature Geoscience),题为:The September 2009 Padang Earthquake。信中提出警告:印度尼西亚苏门答腊沿海地区或将发生引发巨大海啸的强烈地震,其灾害程度足以造成与2004年南亚大海啸相匹敌的惨重伤亡,提醒居民要为更加强烈的地震来袭做好准备。为此,"Nature Geoscience"特发表了一篇社论,题为:Earthquakes off Sumatra(见本期译文"苏门答腊近海地震")。下边是John McCloskey等致"Nature Geoscience"的信函译文。 展开更多
关键词 印度尼西亚 地震 强震 连发
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