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Impact of climate change and human activities on the spatiotemporal dynamics of surface water area in Gansu Province, China
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作者 LU Haitian ZHAO Ruifeng +3 位作者 ZHAO Liu LIU Jiaxin LYU Binyang YANG Xinyue 《Journal of Arid Land》 SCIE CSCD 2024年第6期798-815,共18页
Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with comp... Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with complex terrain and variable climate,as the research subject.Based on Google Earth Engine,we used Landsat data and the Open-surface Water Detection Method with Enhanced Impurity Control method to monitor the spatiotemporal dynamics of surface water area in Gansu Province from 1985 to 2022,and quantitatively analyzed the main causes of regional differences in surface water area.The findings revealed that surface water area in Gansu Province expanded by 406.88 km2 from 1985 to 2022.Seasonal surface water area exhibited significant fluctuations,while permanent surface water area showed a steady increase.Notably,terrestrial water storage exhibited a trend of first decreasing and then increasing,correlated with the dynamics of surface water area.Climate change and human activities jointly affected surface hydrological processes,with the impact of climate change being slightly higher than that of human activities.Spatially,climate change affected the'source'of surface water to a greater extent,while human activities tended to affect the'destination'of surface water.Challenges of surface water resources faced by inland arid and semi-arid areas like Gansu Province are multifaceted.Therefore,we summarized the surface hydrology patterns typical in inland arid and semi-arid areas and tailored surface water'supply-demand'balance strategies.The study not only sheds light on the dynamics of surface water area in Gansu Province,but also offers valuable insights for ecological protection and surface water resource management in inland arid and semi-arid areas facing water scarcity. 展开更多
关键词 surface water area terrestrial water storage Open-surface Water Detection Method with Enhanced Impurity Control method Google earth Engine climate change human activities inland arid and semi-arid areas
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Lightweight Surface Litter Detection Algorithm Based on Improved YOLOv5s 被引量:1
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作者 Zunliang Chen Chengxu Huang +1 位作者 Lucheng Duan Baohua Tan 《Computers, Materials & Continua》 SCIE EI 2023年第7期1085-1102,共18页
In response to the problem of the high cost and low efficiency of traditional water surface litter cleanup through manpower,a lightweight water surface litter detection algorithm based on improved YOLOv5s is proposed ... In response to the problem of the high cost and low efficiency of traditional water surface litter cleanup through manpower,a lightweight water surface litter detection algorithm based on improved YOLOv5s is proposed to provide core technical support for real-time water surface litter detection by water surface litter cleanup vessels.The method reduces network parameters by introducing the deep separable convolution GhostConv in the lightweight network GhostNet to substitute the ordinary convolution in the original YOLOv5s feature extraction and fusion network;introducing the C3Ghost module to substitute the C3 module in the original backbone and neck networks to further reduce computational effort.Using a Convolutional Block Attention Mechanism(CBAM)module in the backbone network to strengthen the network’s ability to extract significant target features from images.Finally,the loss function is optimized using the Focal-EIoU loss func-tion to improve the convergence speed and model accuracy.The experimental results illustrate that the improved algorithm outperforms the original Yolov5s in all aspects of the homemade water surface litter dataset and has certain advantages over some current mainstream algorithms in terms of model size,detection accuracy,and speed,which can deal with the problems of real-time detection of water surface litter in real life. 展开更多
关键词 surface litter detection LIGHTWEIGHT YOLOv5s GhostNet deep separable convolution convolutional block attention mechanism(CBAM)
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Interrelationships between Length of the Day, Moon Distance, Phanerozoic Geodynamic Cycles, Tidal Dissipation and Earth’s Core: Review and Analysis
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作者 Heinz-Jürgen Brink 《International Journal of Geosciences》 CAS 2024年第5期396-415,共20页
The rotation of the Earth and the related length of the day (LOD) are predominantly affected by tidal dissipation through the Moon and the growth of the Earth’s core. Due to the increased concentration of mass around... The rotation of the Earth and the related length of the day (LOD) are predominantly affected by tidal dissipation through the Moon and the growth of the Earth’s core. Due to the increased concentration of mass around the rotation axis of the spinning Earth during the growth of the core the rotation should have been accelerated. Controversially the tidal dissipation by the Moon, which is mainly dependent on the availability of open shallow seas and the kind of Moon escape from a nearby position, acts towards a deceleration of the rotating Earth. Measurements of LOD for Phanerozoic and Precambrian times open ways to solve questions concerning the geodynamical history of the Earth. These measurements encompass investigations of growth patterns in fossils and depositional patterns in sediments (Cyclostratigraphy, Tidalites, Stromatolites, Rhythmites). These patterns contain information on the LOD and on the changing distance between Earth and Moon and can be used as well for a discussion about the growth of the Earth’s core. By updating an older paper with its simple approach as well as incorporating newly published results provided by the geoscientific community, a moderate to fast growth of the core in a hot early Earth will be favored controversially to the assumption of a delayed development of the core in an originally cold Earth. Core development with acceleration of Earth’s rotation and the contemporaneous slowing down due to tidal dissipation during the filling of the ocean may significantly interrelate. 展开更多
关键词 Length of the Day Moon Distance Phanerozoic Geodynamic Cycles Tidal Dissipation earths Core
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Effect of rare earths surface treatment on tribological properties of carbon fibers reinforced PTFE composite under oil-lubricated condition 被引量:6
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作者 上官倩芡 程先华 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第4期584-589,共6页
The effect of rare earths (RE) surface treatment of carbon fibers (CF) on tribological properties of CF reinforced polytetrafluoroethylene (PTFE) composites under oil-lubricated condition was investigated. Exper... The effect of rare earths (RE) surface treatment of carbon fibers (CF) on tribological properties of CF reinforced polytetrafluoroethylene (PTFE) composites under oil-lubricated condition was investigated. Experimental results revealed that RE treated CF reinforced PTFE (CF/PTFE) composite had the lowest friction coefficient and wear under various applied loads and sliding speeds compared with untreated and air-oxidated composites. X-ray photoelectron spectroscopy (XPS) study of carbon fiber surface showed that, after RE treatment, oxygen concentration increased obviously, and the amount of oxygen-containing groups on CF surfaces were largely increased. The increase in the amount of oxygen-containing groups enhanced interfacial adhesion between CF and PTFE matrix. With strong interfacial adhesion of the composite, stress could be effectively transmitted to carbon fibers; carbon fibers were strongly bonded with VITE matrix, and large scale rubbing-off of PTFE be prevented, therefore, tribological properties of the composite was improved. 展开更多
关键词 CF/PTFE composites surface treatment tribological property oil-lubrication rare earths
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Understanding the Interactions between Climate Change,Landscape Evolution,Surface Processes and Tectonics in the Earth System:What Can the Studies of Chinese Deserts Contribute? 被引量:5
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作者 YANG Xiaoping Bernhard EITEL 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第4期1444-1454,共11页
Due to large deserts on Earth surface a thorough understanding of climate change, landscape evolution and geomorphological processes having occurred in deserts is crucial for Earth System Science. The landscapes in de... Due to large deserts on Earth surface a thorough understanding of climate change, landscape evolution and geomorphological processes having occurred in deserts is crucial for Earth System Science. The landscapes in deserts are, however, diverse and different over the globe with regard to their geomorphological nature, human activities and geological histories. In the last decades a great number of efforts have been put to the investigation of the initial timing of the occurrence of arid climate, e. g. in northwestern China. Silty sediments in the downwind directions have been used to deduce the histories of deserts. In general, there is a lack of knowledge about processes and landscapes in Chinese drylands between the initial Miocene silt sedimentation at desert margins and the late Quaternary multiple occurrences of wetter climate with assumed large lakes in many of the deserts in northern China. The geomorphological concept of three primary triggering factors, i.e., the sediment supply, sediment availability and transport capacity of wind, and additionally the underground geology need to be fully considered for a better understanding of the environmental histories of sand seas which should not be viewed as equivalent for deserts because sand seas cover between 〈 1% and ca. 45% of the desert areas in various continents dependent on a complex interaction between various processes of both exogenous and endogenous origins. 展开更多
关键词 DEsERT sand sea earth surface process global change Quaternary geology GEOMORPHOLOGY
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Surface Tension Modeling of Molten Rare Earth Containing Halide Mixtures 被引量:2
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作者 严丽君 乔芝郁 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第4期308-311,共4页
关键词 rare earths molten salts surface tension calculation Butler′s equatl
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Effect of Rare Earths on the Wear Resistance and High Temperature Oxidation Resistance of H13 Steel Surface-Treated with S-N-C Co-diffusion 被引量:2
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作者 胡正前 张文华 《Journal of Rare Earths》 SCIE EI CAS CSCD 1998年第3期68-72,共5页
Steel H13 was put in non toxic salt bath with addition of CeO 2 for co diffusion of sulfur, nitrogen and carbon and followed by oxidation treatment. The effect of rare earths on the improvement of wear resistance a... Steel H13 was put in non toxic salt bath with addition of CeO 2 for co diffusion of sulfur, nitrogen and carbon and followed by oxidation treatment. The effect of rare earths on the improvement of wear resistance and high temperature oxidation resistance of steel H13 was studied using scanning electron microscope, energy dispersive spectrometry and X ray diffraction. The results show that compared to the surface treatment without rare earth addition, the treatment with addition of rare earths improves the wear resistance and high temperature resistance to oxidation of steel H13. Under the conditions of 30 N and 2 h, the wear weight loss was decreased by 40%, and the friction coefficient was reduced from 0 25 to 0 22; whereas for 150 N and 0 2 h, the wear weight loss was decreased by 24%, and the friction coefficient was reduced from 0 35 to 0 32. For the oxidation at 700 ℃ and 4 h, the rate of weight gain decreased to only about 1/30 of that without rare earths. 展开更多
关键词 ZK(]Rare earths s N C co diffusion Oxidation treatment Wear resistance Oxidation resistance
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Variations in rare earth elements with environmental factors in lake surface sediments from 17 lakes in western China 被引量:3
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作者 DU Ding-ding CHEN Liu-qin +1 位作者 BAI Yong-hui HU Hai-ping 《Journal of Mountain Science》 SCIE CSCD 2021年第7期1811-1822,共12页
Numerous lakes in western China are excellent sites for understanding environmental change.However,what dominates rare earth element(REE) variations are still under debate in the lake environmental research.In this st... Numerous lakes in western China are excellent sites for understanding environmental change.However,what dominates rare earth element(REE) variations are still under debate in the lake environmental research.In this study,we selected 28 surface sediment samples from 17 lakes(i.e.largescale lakes,small water bodies,etc.) in the QinghaiTibet Plateau and Xinjiang area.These samples were analyzed to reveal the behavior of the REEs and major elements.These REE patterns are characterized by light rare earth element(LREE) enrichment,weak Ce anomaly(0.84-0.98,0.94 on average) and negative Eu anomaly(0.53-1.00,0.67 on average).The homogeneous REE patterns may reflect similar REE of the source lithologys.However,the REE abundances showed some significant differences.In this study,water chemistry data analyses inferred that the highly REE values appear possibly in the saltwater lake,and also related to carbonate mineral,whereas p H played a minor role in REE concentrations.In large-scale lakes(e.g.Lake Bosten and Lake Ulungur),the results showed that the relatively larger REE values are in the margins of lakes.Moreover,lower REE contents are towards the central region.Comprehensive study suggested that five major factors control the REE contents:(1) The REE tends to increase with the increase of the weathering intensity.(2) Likewise,heavy mineral(i.e.rutile,anatase,zircon,etc.) are probably primary in these sediments because they are highly enriched in the REE.(3) The contribution of Fe-Mn oxides is significant in sediments because their concentrations highly correlate with the REE.(4) The carbonate mineral(mainly calcite) played a significant role on the REE values in the lakes because the REEs are incorporated into the carbonate minerals generating the low REE concentrations.(5) Major element analysis,mineral analysis,and grain-size data analysis showed that the REE distribution is chiefly influenced by finer grain-size component of lake sediments due to the decreasing proportion of quartz and feldspar than coarser one.Moreover,the clay minerals in finer grain-size sediments can highly absorb the REE. 展开更多
关键词 Western China Lake surface sediments Rare earth elements Environmental factors
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Study on Earth Surface Potential and DC Current Distribution around DC Grounding Electrode 被引量:1
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作者 Zhi-chao Ren Chun-yan Ye Hai-yan Wang 《Energy and Power Engineering》 2013年第4期792-796,共5页
DC magnetic biasing problem,caused by the DC grounding electrode, threatened the safe operation of AC power grid. In this paper, the characteristics of the soil stratification near DC grounding electrode was researche... DC magnetic biasing problem,caused by the DC grounding electrode, threatened the safe operation of AC power grid. In this paper, the characteristics of the soil stratification near DC grounding electrode was researched. The AC-DC interconnected large-scale system model under the monopole operation mode was established. The earth surface potential and DC current distribution in various stations under the different surface thickness was calculated. Some useful conclusions are drawn from the analyzed results. 展开更多
关键词 DC GROUNDING ELECTRODE Magnetic BIAsING soil sTRATIFICATION earth surface Potential DC Current DIsTRIBUTION
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Relationships between Earth’s Rotation or Revolution and Geographical Extent of the Global Surface Monsoons 被引量:1
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作者 Mbane Biouele César 《Atmospheric and Climate Sciences》 2014年第1期47-52,共6页
Monsoon seasons, occasionally also known as wet seasons or trade-wind littoral seasons, are found in the regions where there is a complete seasonal reversal of the prevailing surface winds. Accompanying these shifts i... Monsoon seasons, occasionally also known as wet seasons or trade-wind littoral seasons, are found in the regions where there is a complete seasonal reversal of the prevailing surface winds. Accompanying these shifts in the prevailing surface winds are modulations in rainfall activity. Given the fact that our knowledge of the monsoons is mainly based on the interpretation of the mean values of precipitation, cloudiness and winds;relationships between earth’s rotation or revolution and geographical extent of the global surface monsoons deserve to be highlighted. In the abundant literary and audiovisual production devoted to monsoons worldwide and despite the fact that everyone agrees with physical law which shows that Coriolis force acts to the right in the northern hemisphere (to the left in the southern hemisphere), there is no reference to the relationship between Coriolis force (due to earth’s rotation) effects on troposphere general circulation and geographical extent of the global surface monsoons. Furthermore knowing that the ITCZ oscillations on either side of the equators (due to earth’s revolution) determine the seasons (mainly winter and summer), it is clear that earth’s revolution also plays a crucial role in the seasonal reversal of the prevailing surface winds observed in the regions where monsoons are found. Our main objective is to provide a rational answer to the question: what is a monsoon? 展开更多
关键词 seasonal Reversal of the Prevailing surface Winds CORIOLIs Force earths ROTATION ITCZ (Inter-Tropical Convergence Zone) Oscillations earths REVOLUTION
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GPS and Google Earth based 3D assisted driving system for trucks in surface mines 被引量:9
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作者 SUN Enji NIETO Antonio LI Zhongxue 《Mining Science and Technology》 EI CAS 2010年第1期138-142,共5页
In order to reduce the number of surface mining accidents related to low visibility conditions and blind spots of trucks and to provide 3D information for truck drivers and real time monitored truck information for th... In order to reduce the number of surface mining accidents related to low visibility conditions and blind spots of trucks and to provide 3D information for truck drivers and real time monitored truck information for the remote dispatcher, a 3D assisted driving system (3D-ADS) based on the GPS, mesh-wireless networks and the Google-Earth engine as the graphic interface and mine-mapping server, was developed at Virginia Tech. The research results indicate that this 3D-ADS system has the potential to increase reliability and reduce uncertainty in open pit mining operations by customizing the local 3D digital mining map, con-structing 3D truck models, tracking vehicles in real time using a 3D interface and indicating available escape routes for driver safety. 展开更多
关键词 辅助驾驶系统 卡车司机 三维信息 地球 露天矿 GPs 全球定位系统 露天采矿
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Pretreatment of Chrysotile With Rare Earth Compounds Lowered Its Cytotoxicity by Lessening Surface Charges 被引量:1
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作者 FAN JING-GUANG WANG QI-EN +3 位作者 LIU SHI-JIE WU WEI-DONG JIA GUANG AND ZHOU LI-LI(National Institute for Occupational Safety and Health, Ministry of Labour, Beijing 100029, China Department of Occupational Health, School of Public Health, Beijing Medical Univers 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1998年第2期125-132,共8页
Pathological effects of asbestos are probably dependent on the special surface properties of the fibers, such as surface charge, surface metal ions. The present study was designed to determine whether the pretreatment... Pathological effects of asbestos are probably dependent on the special surface properties of the fibers, such as surface charge, surface metal ions. The present study was designed to determine whether the pretreatment of chrysotile asbestos fibers (CAF) with rare earth compounds (REC) solution can reduce their pathogenicity. The results showed that REC-pretreated CAF induced less nitrogen oxide (NO) production by alveolar macrophages (AM). In addition, the pretreatment lowered the capacity of hemolysis and the methylene blue (MB) adsorption of the native CAF. These findings suggested that the pretreatment of CAF with REC solution reduced the in vitro toxicity of CAF by lessening its surface charges. Nevertheless, the pathogenicity and the carcinogenicity of REC-pretreated CAF in vivo remain to be investigated. 展开更多
关键词 BR Pretreatment of Chrysotile With Rare earth Compounds Lowered Its Cytotoxicity by Lessening surface Charges
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Coseismic surface rupture characteristics and earthquake damage analysis of the eastern end of the 2021 M_(S)7.4 Madoi(Qinghai)earthquake 被引量:1
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作者 Yanbo Zhang Yueren Xu +6 位作者 Wenqiao Li Runchao Liu Ruoyu Mu Jiayi Li Da Zhang Haofeng Li Qinjian Tian 《Earthquake Research Advances》 CSCD 2022年第2期49-58,共10页
At 02:04 on May 22,2021,an M_(S)7.4 earthquake occurred in Madoi County in Qinghai Province,China.This earthquake is the largest seismic event in China since the 2008M_(S) 8.0 Wenchuan earthquake.Thus,it is critical t... At 02:04 on May 22,2021,an M_(S)7.4 earthquake occurred in Madoi County in Qinghai Province,China.This earthquake is the largest seismic event in China since the 2008M_(S) 8.0 Wenchuan earthquake.Thus,it is critical to investigate surface deformation and damage in time to accurately understand the seismogenic structure of the Madoi earthquake and the seismogenic capacity of the blocks in this region.This study focuses on the Xuema Village,located at the eastern end of the coseismic surface ruptures produced by the event,and assesses the deformation and seismic damage in this area based on field surveys,UAV photogrammetry,and ground penetrating radar(GPR).The results indicate that the rupture scale is substantially smaller at the eastern end of the rupture zone compared to other segments.En echelon type shear tensile fractures are concentrated in a width range of 50–100 m,and the width of single fractures ranges from 20 to 30 cm.In contrast,the degree of seismic damage significantly increases at this site.All of the brick and timber houses are damaged or collapsed,while the steel frame structures and the color steel houses are slightly damaged.More than 80%of the bridge decks on the Changma River Bridge collapse,similar to the terraces along the Youerqu and Changma Rivers and the cut slopes of Provincial Highway S205.We infer that the seismogenic fault of the Madoi earthquake exerts a tail effect in this segment.The tension zone has led to a reduction at the eastern end of the rupture zone,causing shaking damage.Local topography and buildings without earthquake-resistant construction along the strike of the rupture zone have undergone different levels of seismic damage. 展开更多
关键词 2021-5-22 Madoi M_(s)7.4 earthquake Coseismic surface rupture Kunlunshankou-Jiangcuo fault Bayan Har Block Tibetan Plateau
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SURFACE MODIFICATION ON STEEL BY RARE EARTH AND LASER TREATMENT
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作者 Shen, Yifu Feng, Zhongchao +1 位作者 Chen, Jizhi Liang, Yong 《中国有色金属学会会刊:英文版》 EI CSCD 1997年第4期77-80,共4页
SURFACEMODIFICATIONONSTEELBYRAREEARTHANDLASERTREATMENT①ShenYifu1,2,FengZhongchao1,ChenJizhi1,LiangYong11Inst... SURFACEMODIFICATIONONSTEELBYRAREEARTHANDLASERTREATMENT①ShenYifu1,2,FengZhongchao1,ChenJizhi1,LiangYong11InstituteofMetalResea... 展开更多
关键词 RARE earth LAsER TREATMENT surface MODIFICATION
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Influence of Rare Earth Composite Phosphate on Surface Free Energy of Ceramic Glaze
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作者 张晋 梁金生 +3 位作者 欧秀芹 王丽娟 李计元 彭引民 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期156-159,共4页
Rare earth composite phosphate (RECP) was doped into the ceramic glazes. The contact angle and surface free energy were characterized by the OCA-30 automatism contact angle test system. Through studied the influence o... Rare earth composite phosphate (RECP) was doped into the ceramic glazes. The contact angle and surface free energy were characterized by the OCA-30 automatism contact angle test system. Through studied the influence of RECP on the surface free energy of ceramic glaze and movement modality of oil on the ceramic glaze in the water, the results show that the ceramic surface free energy increase obviously after dope RECP. Analysis and calculation show that the surface free energy increase mainly profited from the surface hydroxyl groups increase. 展开更多
关键词 surface free energy polar force dispersion force ceramic glaze rare earth oxide
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Study on Physical Process of Surface Oxidation of Rare Earth-Transition Metal Amorphous Magneto-Optical Thin Films
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作者 沈德芳 金丽娜 +1 位作者 俞祥游 王丽娟 《Journal of Rare Earths》 SCIE EI CAS CSCD 1992年第4期280-284,共5页
By using surface effects(Auger electron spectroscopy,X-ray photoelectron spectroscopy,polar Kerr effect)and volume effects(magnetization,torque curve)the physical process of surface oxidation of rare earth-transition ... By using surface effects(Auger electron spectroscopy,X-ray photoelectron spectroscopy,polar Kerr effect)and volume effects(magnetization,torque curve)the physical process of surface oxidation of rare earth-transition metal amorphous magneto-optical thin films was studied in this paper.The rare earth elements oxidize preferentially and rich at the film surface,and the transition metals deplete in oxidation layer.Fe_2O_3 in the surface oxidation layer contributes to the planar magnetization,and thereby the anomalous peak appears near 180° on the torque curves and the amplitude of the peaks is related to the depth of surface oxidation layers.The iron bonds to oxygen easier than the cobolt.RE-Co magneto-optieal thin films have good properties of resistance to oxidation and humidity. 展开更多
关键词 Rare earth Magneto-o tical thin film Thin film oxidation surface energy spectroscopy Magneto-optical effect
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Effect of Surface Nanocrystallization Induced by Fast Multiple Rotation Rolling on Cr-Rare Earth-Boronizing for Steel 45 under Low-Temperature 被引量:1
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作者 Xingdong Yuan Bin Xu Yucheng Cai 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第2期118-122,共5页
In this paper,fast multiple rotation rolling( FMRR) is applied to fabricate a nanostructured layer on the surface of steel 45. The FMRR samples are then Cr-Rare earth-boronized under low-temperature. The boride layer ... In this paper,fast multiple rotation rolling( FMRR) is applied to fabricate a nanostructured layer on the surface of steel 45. The FMRR samples are then Cr-Rare earth-boronized under low-temperature. The boride layer is characterized by using Scanning electron microscopy( SEM) and X-ray diffraction( XRD).Experimental results indicate that the thickness of the boride layer is greatly increased by surface nanocrystallization. The boride layer with relatively continuous structure instead of the zigzag teeth structure is obtained,and the penetrating rate is enhanced by 2. 5-3. 7 times when the FMRR samples are Cr-Rare earthboronized at the temperature of 570 ℃,600 ℃ and 650 ℃ for 6 h. The boride layer fabricated on the FMRR sample consists of single phase Fe2 B. Severe plastic deformation with the grain size of approximately 100 nm in the top surface layer of steel 45 is observed,and the thickness of the plastic deformation layer is about 30 μm.The microstructure in the top surface layer is characterized by Transmission electron microscopy( TEM). Grain boundaries are largely increased with high stacking fault energy after FMRR, leading to a significant enhancement of RE boron-chromizing speed. 展开更多
关键词 surface nanocrystallization fast multiple rotation rolling Cr-Rare earth-boronizing low temperature boride layer
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Earth’s Atmosphere Prevailing Surface Winds Based on Effectiveness of Mbane Biouele Formula Derived in 2009
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作者 César Mbane Biouele 《Atmospheric and Climate Sciences》 2014年第2期192-198,共7页
Any system designed to simulate the earth's atmosphere general circulation, must necessarily be based on the spatial-or temporal average conditions. Irregularities in the profiles of air motions that we observe on... Any system designed to simulate the earth's atmosphere general circulation, must necessarily be based on the spatial-or temporal average conditions. Irregularities in the profiles of air motions that we observe on daily weather maps often make lose any real meaning to the general circulation. As complicated and inconsistent that is the daily traffic of air particles, it is interesting to define a general circulation characteristic of the average air transportation around the globe. Indeed, this transport responds to a need to transfer heat from the equator (heat source) to the poles (cold sources). Mbane Biouele formula (2009), derived from Clausius-Clapeyron relation (1832), now allows faithful and unique representation of the tricellular general circulation: Hence, the possibility of access to the earth’s atmosphere prevailing surface winds in summer as well as winter. 展开更多
关键词 earths ATMOsPHERE General CIRCULATION DAILY Traffic of Air Particles Heat Transfer from the EQUATOR to the POLEs Prevailing surface Winds
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Identification and Interpretation of Earth’s Atmosphere Dynamics’ and Thermodynamics’ Similarities between Rogue Waves and Oceans’ Surface Geostrophic Wind
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作者 César Mbane Biouele 《Open Journal of Marine Science》 2016年第2期238-246,共9页
In their daily practices, meteorologists make extensive use of the geostrophic wind properties to explain many weather phenomena such as the meaning and direction of the horizontal winds that take place around the low... In their daily practices, meteorologists make extensive use of the geostrophic wind properties to explain many weather phenomena such as the meaning and direction of the horizontal winds that take place around the low atmospheric pressures. The biggest challenge that faces the public who is interested in information disseminated by meteorologists is to know exactly what means the geostrophic wind. Besides the literal definitions scattered in very little scientific work, there is unfortunately no book which gives importance to the algebraic definition of the geostrophic wind. Our work shows that to better understand the behavior of natural phenomena, it is essential to combine the theories with based observations. Obviously, observations cannot be relevant without a theory that guides the observers. Conversely, no theory can be validated without experimental verification. Synoptic observations show that in the “free atmosphere!” the wind vectors are very nearly parallel to isobars, and the flow is perpendicular to the horizontal pressure gradient force, at least at any given instant. This kind of information recommends great caution when making geostrophic approximations. Our work also shows that for tornadoes, there is no need to move away from the surface of the oceans to observe the geostrophic balance. Undoubtedly, identification and interpretation of earth’s atmosphere dynamics’ and thermodynamics’ similarities between rogue waves and oceans’ surface geostrophic wind will be an easy exercise to researchers who will give importance to result provided by this paper. 展开更多
关键词 earths Atmosphere Dynamics and Thermodynamics similarities Rogue Waves Ocean’s surface Geostrophic Wind
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Spatial-temporal variations in near-surface soil freeze-thaw cycles in the source region of the Yellow River during the period 2002–2011 based on the Advanced Microwave Scanning Radiometer for the Earth Observing System(AMSR-E) data 被引量:5
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作者 WANG Rui ZHU Qingke +1 位作者 MA Hao AI Ning 《Journal of Arid Land》 SCIE CSCD 2017年第6期850-864,共15页
Detecting near-surface soil freeze-thaw cycles in high-altitude cold regions is important for understanding the Earth's surface system, but such studies are rare. In this study, we detected the spatial-temporal varia... Detecting near-surface soil freeze-thaw cycles in high-altitude cold regions is important for understanding the Earth's surface system, but such studies are rare. In this study, we detected the spatial-temporal variations in near-surface soil freeze-thaw cycles in the source region of the Yellow River(SRYR) during the period 2002–2011 based on data from the Advanced Microwave Scanning Radiometer for the Earth Observing System(AMSR-E). Moreover, the trends of onset dates and durations of the soil freeze-thaw cycles under different stages were also analyzed. Results showed that the thresholds of daytime and nighttime brightness temperatures of the freeze-thaw algorithm for the SRYR were 257.59 and 261.28 K, respectively. At the spatial scale, the daily frozen surface(DFS) area and the daily surface freeze-thaw cycle surface(DFTS) area decreased by 0.08% and 0.25%, respectively, and the daily thawed surface(DTS) area increased by 0.36%. At the temporal scale, the dates of the onset of thawing and complete thawing advanced by 3.10(±1.4) and 2.46(±1.4) days, respectively; and the dates of the onset of freezing and complete freezing were delayed by 0.9(±1.4) and 1.6(±1.1) days, respectively. The duration of thawing increased by 0.72(±0.21) day/a and the duration of freezing decreased by 0.52(±0.26) day/a. In conclusion, increases in the annual minimum temperature and winter air temperature are the main factors for the advanced thawing and delayed freezing and for the increase in the duration of thawing and the decrease in the duration of freezing in the SRYR. 展开更多
关键词 Advanced Microwave scanning Radiometer for the earth Observing system air temperature near-surface soil freeze-thaw cycles source region of the Yellow River
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