期刊文献+
共找到48,700篇文章
< 1 2 250 >
每页显示 20 50 100
Research on the Reconstruction and Renewal of the Landscape Space of Industrial Sites in Post-industrial Era:A Case Study of Guangzhou Zilintang Art Town
1
作者 GAO Qing ZENG Junfeng 《Journal of Landscape Research》 2021年第3期25-28,共4页
With the rapid development of urbanization,traditional old industrial areas can not cope with the impact of the new wave of urbanization and have been abandoned,demolished and remodeled.Solving the pollution problem o... With the rapid development of urbanization,traditional old industrial areas can not cope with the impact of the new wave of urbanization and have been abandoned,demolished and remodeled.Solving the pollution problem of industrial wasteland has become an important part of urban renewal research.Based on the development of industrial sites,the paper discusses the design principles and methods of industrial sites.Through the case analysis of the industrial site of Guangzhou Zilintang Art Town,the paper excavates the deep cultural deposits in the post-industrial era and analyzes the renewal,utilization,transformation and regeneration of the landscape space of industrial sites. 展开更多
关键词 Industrial site Landscape design Space transformation Renewal and utilization
下载PDF
A Brief Reading of American Urban Culture in Post-Industrialization Era
2
作者 杨雁 范金玲 陈玲玲 《海外英语》 2020年第1期184-185,202,共3页
In the wake of great expansion of cities as centers of production,the post-industrialization era saw American urban tran-sitions and transformations with cultural diversification highlighting consumption,service,marke... In the wake of great expansion of cities as centers of production,the post-industrialization era saw American urban tran-sitions and transformations with cultural diversification highlighting consumption,service,marketing and cultural integration.Cul-tural variations in cities,under the influence of non-material production,constantly worked for urban re-invention and urban re-newal,facilitating and expediting a high-level urban development. 展开更多
关键词 American Cities CULTURE post-industrialization Era
下载PDF
可持续场地倡议(SITES)评价体系在中国城市绿地建设中的研究进展及适用性讨论
3
作者 林广思 朱欣 贺肖淇 《广东园林》 2024年第2期2-6,共5页
建设可持续的城市绿地是风景园林行业实现可持续发展的重要途径。然而,中国目前缺乏指导可持续景观建设的标准体系。可持续场地倡议(SITES)体系的提出和引入为国内相关研究提供了新的切入点。以SITES评价体系为研究对象,概述其起源、主... 建设可持续的城市绿地是风景园林行业实现可持续发展的重要途径。然而,中国目前缺乏指导可持续景观建设的标准体系。可持续场地倡议(SITES)体系的提出和引入为国内相关研究提供了新的切入点。以SITES评价体系为研究对象,概述其起源、主要内容等,明确其在城市绿地项目建设中的应用价值,全面总结了SITES评价体系在国内研究与应用方面的进展,同时深入探讨了其在中国城市绿地建设中的适用性和局限性。SITES在关注“场地”尺度、覆盖全生命周期、设置“门槛”条件以及全球统一标准等方面展现了较强的适用性,然而,在实际应用于中国城市绿地项目时存在一定的局限性,包括SITES标准与国内标准规范的不匹配,分值权重的失衡,缺乏政府相关福利政策支持和推广受限制等问题。 展开更多
关键词 城市绿地 可持续景观 可持续场地倡议(siteS) 景观绩效
下载PDF
Investigation of soil and groundwater environment in urban area during post-industrial era: A case study of brownfield in Zhenjiang, Jiangsu Province, China 被引量:6
4
作者 Shuai Yang Wei-ya Ge +1 位作者 Hong-han Chen Wen-li Xu 《China Geology》 2019年第4期501-511,共11页
With the adjustment of industrial structure,many high pollution enterprises will gradually shut down.This process will produce a large number of high-risk pollution plots and cause a series of environmental problems.I... With the adjustment of industrial structure,many high pollution enterprises will gradually shut down.This process will produce a large number of high-risk pollution plots and cause a series of environmental problems.In this study,geophysical detection and direct push technology were applied to investigate soil and groundwater pollution in a typical brownfield in Zhenjiang,Jiangsu province,China.The results showed that Chlorotoluene and its ramification were the main pollutants for the brownfield.Pollution decreased with depth and was quite uneven in the brownfield.Production and wastewater treatment areas were heavily polluted,where volatile organic compounds contaminated and semi-volatile organic compounds were found 12 m and 15 m below the land surface,respectively.About 18880 m3 groundwater was contaminated.This study is significant to develop a geological survey work mode for the postindustrial era. 展开更多
关键词 post-industrial BROWNFIELD Organic INTERMEDIATE Environmental GEOLOGICAL survey engineering Soil and GROUNDWATER pollution Jiangsu PROVINCE
下载PDF
Post-industrial Economic Restructuring and Wage Inequality in Urban China, 2003-2015: A Sectoral Perspective 被引量:1
5
作者 YANG Fiona Fan HU Fox Zhiyong WANG Yuhua 《Chinese Geographical Science》 SCIE CSCD 2020年第3期516-531,共16页
Income inequality in urban China has attracted growing attention from China’s urban researchers and policy makers. Whereas many studies have interrogated the pattern and process of the income gap in Chinese cities un... Income inequality in urban China has attracted growing attention from China’s urban researchers and policy makers. Whereas many studies have interrogated the pattern and process of the income gap in Chinese cities undergoing the institutional transformation from plan to market, relatively little is known about how such unequal distribution of income is related to China’s ongoing structural transformation toward a post-industrial economy. Drawing on a decomposition methodology based on the Theil index, this study aimed to address this lacuna through an empirical investigation of China’s urban wage inequality from a sectoral perspective. Our empirical study identified the low-wage manufacturing sector and the high-wage producer services sector as the two biggest contributors to urban wage inequality in China. Urban wage inequality within the producer services was found to be caused by the spatial concentration of a disproportionate number of high-paying jobs in a few developed, high-tier city-regions on the eastern coast. Our empirical findings have important implications for the formulation of policies to address the income inequality that plagues China’s continuing urbanization. 展开更多
关键词 wage inequality post-industrial economy economic restructuring producer service urban China
下载PDF
"The Closest Thing to God": Post-industrialization and Postmodernism in Tawni O'Dell's Coal Run
6
作者 Charles Cullum 《Cultural and Religious Studies》 2015年第2期92-98,共7页
A growing body of American literature examines the conditions in towns from the Midwest to the Northeast that have been drastically affected by the condition of what has been termed "deindustrialization". These town... A growing body of American literature examines the conditions in towns from the Midwest to the Northeast that have been drastically affected by the condition of what has been termed "deindustrialization". These towns have witnessed the employee downsizing and the eventual collapse of their major industries, such as automobile manufacturing and coal mining, and the fiction about them--termed "deindustrialization literature" by Sherry Lee Linkon--explores how the affected generations cope with these changed circumstances. The novel Coal Run, written in 2004 by Tawni O'Dell's, herself a native of a coal mining region in Western Pennsylvania, is one such example of deindustrialization literature and the focus of this essay. Set in a coal mining town that has been shut down because of a Centralia-like uncontrolled mine fire that opens fissures to a literal kind of hell, the protagonist, Ivan the Great, a former Penn State football star, and other characters attempt to re-orient themselves after the mine---described by Ivan as "the closest thing I had to God"--closes and the effects of that closing are felt. This paper discusses the motifs of ecological ruin, economic disruption, and personal, familial, and community disorientation in the novel. In doing so, the paper considers connections between de- or post-industrialization and postmodernism, particularly as discussed by cultural geographer David Harvey in The Condition of Postmodernity in terms of "the crisis tendency" of capitalism toward "overaccumulation" and the "link between postmodernism and...more flexible modes of capital accumulation". The paper goes on to consider the experiences through which the novel's characters learn to look to the future in ways that may be said to coincide with the ethos of much postmodern American fiction that sets less ambitious but nonetheless still meaningful expectations for human being. 展开更多
关键词 deindustrialization literature post-industrialization POSTMODERNISM American fiction contemporary fiction
下载PDF
A comprehensive review of lunar lava tube base construction and field research on a potential Earth test site 被引量:1
7
作者 Yujie Feng Peng-Zhi Pan +3 位作者 Xuhai Tang Zhaofeng Wang Yuxin Li Altaf Hussain 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1201-1216,共16页
The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission... The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission.Lunar lava tubes are special underground caves formed by volcanic eruptions and are considered as ideal natural shelters and scientific laboratories for lunar base construction.This paper begins with an in-depth overview of the geological origins,exploration history,and distribution locations of lunar lava tubes.Subsequently,it delves into the presentation of four distinctive advantages and typical concepts for constructing bases within lava tubes,summarizing the ground-based attempts made thus far in lunar lava tube base construction.Field studies conducted on a lava tube in Hainan revealed rock compositions similar to those found during the Apollo missions and clear lava tube structures,making it a promising analog site.Lastly,the challenges and opportunities encountered in the field of geotechnical engineering regarding the establishment of lunar lava tube bases are discussed,encompassing cave exploration technologies,in-situ testing methods,geomechanical properties under lunar extreme environments,base design and structural stability assessment,excavation and reinforcement techniques,and simulated Earth-based lava tube base. 展开更多
关键词 Lunar lava tube Lunar base construction Extraterrestrial cave exploration Earth analog site
下载PDF
Contemporary Marxism and Post-industrial Economy
8
作者 Victoria S. Gritsenko 《Journal of Philosophy Study》 2014年第3期195-199,共5页
Karl Marx (1973) scientifically predicted the appearance of some extraordinary tendencies of social development in the second half of the 20th century was given a common name of post-industrial or informational soci... Karl Marx (1973) scientifically predicted the appearance of some extraordinary tendencies of social development in the second half of the 20th century was given a common name of post-industrial or informational society and interpreted as post-bourgeois, post-capitalist, post-business society, and late capitalism. Autonomist Marxism and Perm philosophy school had separately come to a conclusion that all the phenomena noticed by the post-industrial theory could be adequately explained if we consider the historically new form of material labour appearing now. Marx (1973), who predicted this new form, named it automated, scientific, or universal labour. With the appearance of the universal labour, the wealth of the society depends on the universal human powers that help to involve the extensive powers of nature into the production process. Universal labour can not be averaged or measured by the labour time as the abstract labour; it implies high complexity and creativity. Involving increasingly powerful forces of nature and human society, it appears to be the labour of another essence and by its essence, it does not create value. 展开更多
关键词 modem Marxism universal labour destruction of value post-industrial society information
下载PDF
Understanding Bridging Sites and Accelerating Quantum Efficiency for Photocatalytic CO_(2) Reduction 被引量:1
9
作者 Kangwang Wang Zhuofeng Hu +8 位作者 Peifeng Yu Alina M.Balu Kuan Li Longfu Li Lingyong Zeng Chao Zhang Rafael Luque Kai Yan Huixia Luo 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期68-84,共17页
We report a novel double-shelled nanoboxes photocatalyst architecture with tailored interfaces that accelerate quantum efficiency for photocatalytic CO_(2) reduction reaction(CO_(2)RR)via Mo–S bridging bonds sites in... We report a novel double-shelled nanoboxes photocatalyst architecture with tailored interfaces that accelerate quantum efficiency for photocatalytic CO_(2) reduction reaction(CO_(2)RR)via Mo–S bridging bonds sites in S_(v)–In_(2)S_(3)@2H–MoTe_(2).The X-ray absorption near-edge structure shows that the formation of S_(v)–In_(2)S_(3)@2H–MoTe_(2) adjusts the coordination environment via interface engineering and forms Mo–S polarized sites at the interface.The interfacial dynamics and catalytic behavior are clearly revealed by ultrafast femtosecond transient absorption,time-resolved,and in situ diffuse reflectance–Infrared Fourier transform spectroscopy.A tunable electronic structure through steric interaction of Mo–S bridging bonds induces a 1.7-fold enhancement in S_(v)–In_(2)S_(3)@2H–MoTe_(2)(5)photogenerated carrier concentration relative to pristine S_(v)–In_(2)S_(3).Benefiting from lower carrier transport activation energy,an internal quantum efficiency of 94.01%at 380 nm was used for photocatalytic CO_(2)RR.This study proposes a new strategy to design photocatalyst through bridging sites to adjust the selectivity of photocatalytic CO_(2)RR. 展开更多
关键词 Quantum efficiency Electronic structure Steric interaction Bridging sites CO_(2)reduction
下载PDF
The Inner Link Between Economic Globalization and the Formation of American Post-industrial Economy
10
作者 SHI Guangyu 《Cultural and Religious Studies》 2022年第6期319-323,共5页
Economic globalization has a very important impact on the world economic development.The economic globalization,especially after the 1970s,not only promoted the global industry division of labor,but also changed the e... Economic globalization has a very important impact on the world economic development.The economic globalization,especially after the 1970s,not only promoted the global industry division of labor,but also changed the economic structure of the world.From the perspective of global industrial division,many counties have entered post-industrial process,the United States is a case in point.However,economic globalization is an abstract conception,which it consists of trade liberalization,capital globalization,and production decentralization.Therefore,trade liberalization,capital globalization,and production decentralization are important factors for the formation of the post-industrial economy in the United States. 展开更多
关键词 economic globalization United States post-industrial economy
下载PDF
Asymmetric Zn-N_4 atomic sites embedded hollow fibers as stable Zn anode for high-performance Zn-ion hybrid capacitor
11
作者 Yukun Liu Bing Li +5 位作者 Jin Wang Caiyun Li Hongrui Yang Yang Song Sen Zhang Chao Deng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期460-469,I0009,共11页
Zn based electrochemical energy storage systems(EES)have attracted tremendous interests owing to their low cost and high intrinsic safety.Nevertheless,the uncontrolled growth of Zn dendrites and the side reactions of ... Zn based electrochemical energy storage systems(EES)have attracted tremendous interests owing to their low cost and high intrinsic safety.Nevertheless,the uncontrolled growth of Zn dendrites and the side reactions of Zn metal anodes(ZMAs)severely restrict their applications.To address these issues,we design the asymmetric Zn-N_(4) atomic sites embedded hollow fibers(AS-IHF)as the flexible host for stable ZMAs.Through introducing different nitrogen resources in the synthesis,two kinds of coordination,i,e.Zn-N(pyridinic)and Zn-N(pyrrolic),are introduced in the Zn-N_(4) atomic module synchronously.The asymmetric Zn-N_(4) module with regulated micro-environment facilitates the superior zincophilic features and promotes the Zn adsorption.Meanwhile,the highly porous structure of the hollow fiber effectively reduces local current density,homogenize Zn ion flux,and alleviate structure stress.All the advantages endow the high efficiency and good stability for Zn plating/stripping.Both theoretical and experimental results demonstrate the high reversibility,low nucleation overpotential,and dendritefree behavior of the AS-IHF@Zn anode,which afford the high stability in high-rate and long-term cycling.Moreover,the solid-state Zn-ion hybrid capacitor(ZIHC)based on AS-IHF@Zn anode shows the high flexibility,reliability,and superior long-term cycling capability in a wide-range of temperatures(-20-25℃).Therefore,the present work not only gives a new strategy for modulating local environments of single atomic sites,but also propels the development of flexible power sources for diverse electronics. 展开更多
关键词 Asymmetric coordination Single atomic sites Zincophilic sites Dendrite free behavior Zn-ion hybrid capacitor
下载PDF
d-Orbital steered FeN_(4)moiety through N,S dual-site adjustation for zinc-air flow battery
12
作者 Chunzhu Bao Mingwei Tong +1 位作者 Xueli Li Zhonghua Xiang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期8-15,共8页
The implementation of pristine covalent organic polymer(CO_(2)P)with well-defined structure as air electrode may spark fresh vitality to rechargeable zinc-air flow batteries(ZAFBs),but it still remains challenges in s... The implementation of pristine covalent organic polymer(CO_(2)P)with well-defined structure as air electrode may spark fresh vitality to rechargeable zinc-air flow batteries(ZAFBs),but it still remains challenges in synergistically regulating their electronic states and structural porosity for the great device performance.Here,we conquer these issues by exploiting N and S co-doped graphene with COP rich in metal-ligand nitrogen to synergistically construct an effective catalyst for oxygen reduction reaction(ORR).Among them,the N and S co-doped sites with high electronegativity properties alter the number of electron occupations in the d orbital of the iron centre and form electron-transfer bridges,thereby boosting the selectivity of the ORR-catalysed four-electron pathway.Meanwhile,the introduction of COP materials aids the formation of pore interstices in the graphene lamellae,which both adequately expose the active sites and facilitate the transport of reactive substances.Benefiting from the synergistic effect,as-prepared catalyst exhibits excellent half-wave potentials(E_(1/2)=912 mV)and stability(merely 8.8%drop after a long-term durability test of 50000 s).Further,ZAFBs assembled with the N/SG@CO_(2)P catalyst demonstrate exceptional power density(163.8 mW cm^(-2))and continuous charge and discharge for approximately 140 h at 10 mA cm^(-2),outperforming the noble-metal benchmarks. 展开更多
关键词 Nitrogen/sulfurdual sites Metal-coordinated nitrogen sites Covalent organic polymer Oxygen reduction reaction Zn-airflow battery
下载PDF
Comparison of bone artifacts from the Schöningen site in Germany and the Lingjing site in China
13
作者 WANG Hua LI Zhanyang Thijs van KOLFSCHOTEN 《人类学学报》 CSSCI CSCD 北大核心 2024年第2期214-232,共19页
Similarities play an important role in the reconstruction of human physical,cultural and technological evolution.The two sites presented in this paper,the Middle Palaeolithic site Lingjing in China Layer 10 and 11 and... Similarities play an important role in the reconstruction of human physical,cultural and technological evolution.The two sites presented in this paper,the Middle Palaeolithic site Lingjing in China Layer 10 and 11 and the Lower Palaeolithic site Schöningen 13Ⅱ-4,the socalled Schöningen Spear Horizon in Germany,show striking similarities.The archaeological record of both sites includes lithic artifacts as well as a very large assemblage of fossil bones.The preservation of the material at both sites is excellent and the faunas encountered at both sites show many similarities.The faunal lists of both sites include a diverse carnivore guild,an elephant species,two different rhinoceros species,two different equids,different cervids and large bovids.Both sites also yielded bone retouchers as well as a unique record of bone hammers that show identical,unusual flaking and percussion damage.These similarities are remarkable if one takes into account the difference in age(ca 200 kaBP)and the geographical distance between the two sites of ca 8000 km.Therefore,we do not assume a close cultural link between the hominin populations active at both sites.The authors assume that the observed similarities show more or less identical,opportunistic hominin behaviour at both sites located in a comparable environment with more or less similar taphonomic conditions. 展开更多
关键词 PALAEOLITHIC open-air sites bone tools Asia EUROPE
下载PDF
Assessing the Spatial Equality of COVID Testing Sites Maintaining Zero COVID Policy
14
作者 Muhammad Sajid Mehmood Gang Li +3 位作者 Shiyan Zhai Yaochen Qin Annan Jin Lan Li 《Journal of Geographic Information System》 2024年第3期183-200,共18页
Rapid and timely testing is essential to minimize the COVID-19 spread. Decision makers and policy planners need to determine the equal distribution and accessibility of testing sites. This study mainly examines the sp... Rapid and timely testing is essential to minimize the COVID-19 spread. Decision makers and policy planners need to determine the equal distribution and accessibility of testing sites. This study mainly examines the spatial equality of COVID-19 testing sites that maintain a zero COVID policy in Guangzhou City. The study has identified the spatial disparities of COVID testing sites, characteristics of testing locations, and accessibility. The study has obtained information on COVID testing sites in Guangzhou City and population data. Point pattern analyses, Euclidian distance and allocation, and network analyses are the main methods used to achieve the research objectives, and 1183 total COVID testing sites can be recognized in Guangzhou City. Results revealed that spatial disparities could be noticed over the study area. Testing locations of Guangzhou City are highly clustered. The most significant testing sites are located in Haizhu District, which has the third largest population. The highest population density can be identified in Yuexiu District. However, only 94 testing sites are located there. According to all the results, higher disparities can be identified, and a lack of testing sites is located in the north part of the study area. Some people in the northern part have to travel more than 10 km to reach a testing site. Finally, this paper suggests increasing the number of testing sites in the north and south parts of the study area and keeping the same distribution, considering the area, total population, and population density. This kind of research will be helpful to decision-makers in making proper decisions to maintain a zero COVID policy. 展开更多
关键词 COVID-19 Testing sites Spatial Disparities Spatial Equality Guangzhou City ACCESSIBILITY
下载PDF
Characteristics of Gold Mineralization at the Baguiomo Gold Panning Site, Koudougou Region, Burkina Faso, West Africa
15
作者 Pascal Ouiya Aziz Fayçal Tarnagda Martial Eric Fozing 《Open Journal of Geology》 CAS 2024年第1期1-18,共18页
The Birimian Baguiomo formations are located in the northern part of the Boromo greenstone belt. In this belt, the volcanic rocks (tholeiitic basalt, calcalkaline basalt, andesite) hosting the gold mineralization are ... The Birimian Baguiomo formations are located in the northern part of the Boromo greenstone belt. In this belt, the volcanic rocks (tholeiitic basalt, calcalkaline basalt, andesite) hosting the gold mineralization are located in the Kwademen-Baguiomo shear zone. This mineralization, located only a few kilometers from the Kwademen gold deposit, is uncharacterized and, together with the latter, could constitute a gold potential capable of being economically exploitable. It is in this sense that this work is carried out with a view to characterizing the gold mineralization of the Baguiomo gold panning site. To carry out this work, we have made direct field measurements, combined with microstructures, and combined all this with data from geochemical rock analysis of the basalts that are the main host formations. Geochemical data show that tholeitic basalts formed from a mantle plume that was emplaced in an oceanic plateau context. Calc-alkaline basalts and andesites are comparable to Paleoproterozoic tholeitic basalts (PTH3), which are slightly enriched in light rare earths. Fertility tests show that these basalts concentrate between 3 and 6 ppb of gold at the time of accretion, which is sufficient for remobilization of this primary gold during the Eburnian orogeny to yield a deposit of around 4 - 5 Moz. Gold mineralization is associated with pyrite crystals when the latter are disseminated in the rock mass, whereas it is associated with hematite in quartz veins concordant with S1 shear deformation. It is mainly the pyrite crystals in the pressure shadows that contain the gold grains, whose development would be synchronous with micro-shear zone reactivation during the first phase of D1<sub>B</sub> deformation. The second phase of D2<sub>B</sub> deformation, which is a crenulation or fracture schistosity, does not significantly affect the shear deformation that controls mineralization. 展开更多
关键词 Kwademen-Baguiomo Shear Zone Gold Panning site Gold Mineralization Eburnian Orogeny
下载PDF
Ni/ZSM-5 Catalysts for Light Olefin Oligomerization:Effects of Supports and Ni Sites on Activity and Selectivity
16
作者 Zuo Qi Liang Ke +5 位作者 Ma Yirong Jia Yangxiao Liao Mingjie Zheng Jiajun Li Ruifeng Li Wenlin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期15-23,共9页
A series of Ni/ZSM-5 containing a small amount of Ni was prepared by an ion exchanged method.The impact of the n(SiO_(2))/n(Al_(2)O_(3))ratio on the catalytic activity was studied using the samples 0.09Ni/ZSM-5(60)and... A series of Ni/ZSM-5 containing a small amount of Ni was prepared by an ion exchanged method.The impact of the n(SiO_(2))/n(Al_(2)O_(3))ratio on the catalytic activity was studied using the samples 0.09Ni/ZSM-5(60)and 0.09Ni/ZSM-5(130).To determine the interaction between the Ni species and acid sites on the surface of the catalyst,the catalysts were characterized by N2 adsorption-desorption,X-ray diffraction(XRD),scanning electron microscopy(SEM),and UV-vis spectroscopy.The performance of the catalysts for the catalytic oligomerization of 1-hexene was investigated in detail.The nickel species were found to be uniformly distributed in all the catalysts.It was discovered that the oligomerization activity of the catalyst can be improved using Ni species;however,the contribution of Brønsted acids in oligomerization reactions is greater than that of Ni sites and Lewis acids. 展开更多
关键词 nickel ZEOLITE acid sites OLIGOMERIZATION catalyst
下载PDF
An Analysis of the Fragmentation of Observing Time At the Muztagh-Ata Site
17
作者 Wen-Bo Gu Jing Xu +5 位作者 Guo-Jie Feng Xuan Zhang Le-Tian Wang Xin-Liang Wang Ali Esamdin Li-Xian Shen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期29-33,共5页
Cloud cover plays a pivotal role in assessing observational conditions for astronomical site-testing.Except for the fraction of observing time,its fragmentation also wields a significant influence on the quality of ni... Cloud cover plays a pivotal role in assessing observational conditions for astronomical site-testing.Except for the fraction of observing time,its fragmentation also wields a significant influence on the quality of nighttime sky clarity.In this article,we introduce the functionΓ∈[0,1],designed to comprehensively capture both the fraction of available observing time and its continuity.Leveraging in situ measurement data gathered at the Muztagh-Ata site between 2017 and 2021,we showcase the effectiveness of our approach.The statistical result illustrates that the Muztagh-Ata site affords approximately 122 nights that were absolutely clear and 205 very good nights annually,corresponding toΓ≥0.9 andΓ≥0.36 respectively. 展开更多
关键词 site testing-atmospheric effects-methods STATISTICAL
下载PDF
Effects of synthetic site water on bentonite-concrete system for a potential nuclear waste repository
18
作者 Zhao Sun Yong-Gui Chen +3 位作者 Wei-Min Ye Qiong Wang Dong-Bei Wu Zhen-Yu Yin 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3786-3797,共12页
In high-level nuclear waste(HLW)repositories,concrete and compacted bentonite are designed to be employed as buffer materials,which may raise a problem of interactions between concrete and bentonite.These interactions... In high-level nuclear waste(HLW)repositories,concrete and compacted bentonite are designed to be employed as buffer materials,which may raise a problem of interactions between concrete and bentonite.These interactions would lead to mineralogy transformation and buffer performance decay of bentonite under the near field environment conditions in a repository.A small-scale experimental setup was established to simulate the concrete-bentonite-site water interaction system from a potential nuclear waste repository in China.Three types of mortars were prepared to correspond to the concrete at different degradation states.The results permit the determination of the following:(1)The macroproperties of Gaomiaozi(GMZ)bentonite(e.g.swelling pressure,permeability,the final dry density,and water content of reacted samples);(2)The composition evolution of fluids from the synthetic site water-concrete-bentonite interaction systems;(3)The sample characterization including Fourier transform infrared spectroscopy(FTIR)and X-ray powder diffraction(XRD).Under the infiltration of the synthesis Beishan site water(BSW),the swelling pressure of bentonite decreases slowly with time after reaching its second swelling peak.The flux decreases with time during the infiltrations,and it tends to be stable after more than 120 d.Due to the cation exchange reactions in the BSW-concrete-bentonite systems,the divalent cations(Ca and Mg)were consumed,and the monovalent cations(Na and K)were released.The dissolution of minerals in the bentonite such as albite causes Si increasing in the pore water.It was concluded that the hydro-mechanical property degradation of bentonite takes place when it comes into contact with concrete mortar,even under low-pH groundwater conditions.The soil dispersion,the uneven water content,and the uneven dry density in bentonite samples may partly contribute to the swelling decay of bentonite.Therefore,the direct contact with concrete has an obvious effect on the performance of bentonite. 展开更多
关键词 Mock-up device GMZ bentonite site water-concrete-bentonite system Geochemistry Buffer performance
下载PDF
Brønsted-acid sites induced photocatalytic cracking of low-polarity polyethylene plastics
19
作者 Qianyou Wen Quan Zhang +6 位作者 Zhengzheng Liu Huining Wang Shuya Hao Fan Zhang Lijuan Zhang Qing Han Gengfeng Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期509-515,共7页
Polyolefins such as polyethylene(PE)are one of the largest-scale synthetic plastics and play a key role in modern society.However,polyethylene is extremely inert to chemical recycling owing to its lack of chemical fun... Polyolefins such as polyethylene(PE)are one of the largest-scale synthetic plastics and play a key role in modern society.However,polyethylene is extremely inert to chemical recycling owing to its lack of chemical functionality and low polarity,making it one of the most challenging environmental hazards globally.Herein,we developed a phosphorylated CeO_(2)catalyst by an organophosphate precursor and featured efficient photocatalysis of low-density polyethylene(LDPE)without the acid or alkaline pre-treatment.Compared to pristine CeO_(2),the surface phosphorylation allows to introduce Brønsted acid sites,which facilitate to form carbonium ions on LDPE via protonation.In addition,the suitable band structure of the phosphorylated CeO_(2)catalyst enables efficient photoabsorption and generates reactive oxygen species,leading to the C–C bond cleavage of LDPE.As a result,the phosphorylated CeO_(2)catalyst exhibited an outstanding carbon conversion rate of>94%after 48 h of photocatalysis under 50 mW/cm^(2)of simulated sunlight,with a high CO_(2)product selectivity of>99%.Furthermore,the PE microparticles with sizes larger than 10μm released from LDPE plastic wrap were directly and completely degraded by photocatalysis within 12 h,suggesting an attractive and environmentally benign strategy of utilizing solar energy-based photocatalysis for reducing potential hazards of LDPE plastic trashes. 展开更多
关键词 Photocatalytic cracking POLYETHYLENE Surface phosphorylation Bronsted-acid site Carbon conversion
下载PDF
Boost the Utilization of Dense FeN_(4) Sites for High-Performance Proton Exchange Membrane Fuel Cells
20
作者 Yanrong Li Shuhu Yin +4 位作者 Long Chen Xiaoyang Cheng Chongtai Wang Yanxia Jiang Shigang Sun 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期398-405,共8页
Iron-nitrogen-carbon(Fe-N-C)catalysts for the oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs)have seriously been hindered by their poor ORR performance of Fe-N-C due to the low active site... Iron-nitrogen-carbon(Fe-N-C)catalysts for the oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs)have seriously been hindered by their poor ORR performance of Fe-N-C due to the low active site density(SD)and site utilization.Herein,we reported a melamine-assisted vapor deposition approach to overcome these hindrances.The melamine not only compensates for the loss of nitrogen caused by high-temperature pyrolysis but also effectively etches the carbon substrate,increasing the external surface area and mesoporous porosity of the carbon substrate.These can provide more useful area for subsequent vapor deposition on active sites.The prepared 0.20Mela-FeNC catalyst shows a fourfold higher SD value and site utilization than the FeNC without the treatment of melamine.As a result,0.20Mela-FeNC catalyst exhibits a high ORR activity with a half-wave potential(E_(1/2))of 0.861 V and 12-fold higher ORR mass activity than the FeNC in acidic media.As the cathode in a H_(2)-O_(2)PEMFCs,0.20Mela-FeNC catalyst demonstrates a high peak power density of 1.30 W cm^(-2),outstripping most of the reported Fe-N-C catalysts.The developed melamine-assisted vapor deposition approach for boosting the SD and utilization of Fe-N-C catalysts offers a new insight into high-performance ORR electrocatalysts. 展开更多
关键词 fuel cells MELAMINE oxygen reduction reaction site density UTILIZATION
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部