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Analysis of the Influence of Woodcut Works of Anti-Japanese War on the National Spiritual Identity of Young People
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作者 ZHANG Tong-yuan 《Journal of Literature and Art Studies》 2024年第10期916-920,共5页
As one of the important art forms during the Anti-Japanese War in China, woodcut is not only a tool for literary and artistic workers to express the spirit of Anti-Japanese War, but also a medium to inspire the people... As one of the important art forms during the Anti-Japanese War in China, woodcut is not only a tool for literary and artistic workers to express the spirit of Anti-Japanese War, but also a medium to inspire the people and arouse patriotic feelings. Through a systematic analysis of the historical background and artistic characteristics of woodcuts of the Anti-Japanese War and their impact on the national spiritual identity of young people, this paper aims to explore how woodcuts enlightens and inspires young people’s national consciousness through visual language and spiritual connotation, and enhances their sense of belonging to the country and the nation. 展开更多
关键词 anti-japanese woodcut national spirit TEENAGERS identify with artistic influence
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A Study of the People’s Nature in Woodcuts During the Anti-Japanese War in Shanxi
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作者 ZHANG Tong-yuan 《Journal of Literature and Art Studies》 2024年第11期1032-1040,共9页
The anti-Japanese woodcuts focus on the red revolutionary culture and describe the connotation of the Anti-Japanese War era,which is self-evident in the commemorative value of China’s revolutionary struggle history.F... The anti-Japanese woodcuts focus on the red revolutionary culture and describe the connotation of the Anti-Japanese War era,which is self-evident in the commemorative value of China’s revolutionary struggle history.For example,in Shanxi,China,woodcut art activities and social practice promotion activities organized around the theme of the Anti-Japanese War are also everywhere,which all show the people’s nature of the Chinese people during the revolutionary struggle from the two aspects of the red culture of the Anti-Japanese War and traditional art and culture,and its humanistic connotation is quite profound.In this paper,we first introduce the historical origin of woodcut during the Anti-Japanese War,and then show the people’s value connotation of woodcut art activities in Shanxi.This paper mainly discusses the image narration,language and picture narration and construction significance of woodcuts in Shanxi’s War of Resistance,fully reveals the narrative nature of image media,strives to arouse people’s recognition of this period of Shanxi’s War of Resistance culture and history,and reflects the realistic value and significance of Shanxi’s War of Resistance Woodcuts art activities. 展开更多
关键词 people’s nature Shanxi anti-japanese woodcarving image media narrative synergistic effect construction significance humanistic cultural identity
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血红蛋白变异体Hb Fukuyama和Hb North Manchester干扰糖化血红蛋白检测2例报道
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作者 许楠 郑丽红 +5 位作者 薛丽 郭智 张艳 张彦平 耿燕 李友琼 《检验医学》 CAS 2024年第11期1128-1130,共3页
糖化血红蛋白(glycated hemoglobin A1c,HbA_(1c))可反映患者近2~3个月的血糖控制情况[1]。美国糖尿病协会(American Diabetes Association,ADA)在2010年就推荐将HbA_(1c)≥6.5%作为糖尿病的补充诊断标准[2]。血红蛋白(hemoglobin,Hb)... 糖化血红蛋白(glycated hemoglobin A1c,HbA_(1c))可反映患者近2~3个月的血糖控制情况[1]。美国糖尿病协会(American Diabetes Association,ADA)在2010年就推荐将HbA_(1c)≥6.5%作为糖尿病的补充诊断标准[2]。血红蛋白(hemoglobin,Hb)病是珠蛋白基因发生突变引起的一组溶血性遗传性疾病[3]。 展开更多
关键词 血红蛋白变异体 Hb Fukuyama Hb north Manchester 糖化血红蛋白 高效液相色谱法
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Modelling of debris-flow susceptibility and propagation: a case study from Northwest Himalaya 被引量:2
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作者 Hamza DAUD Javed Iqbal TANOLI +5 位作者 Sardar Muhammad ASIF Muhammad QASIM Muhammad ALI Junaid KHAN Zahid Imran BHATTI Ishtiaq Ahmad Khan JADOON 《Journal of Mountain Science》 SCIE CSCD 2024年第1期200-217,共18页
The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study are... The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study area which is extending along Karakorum Highway(KKH) from Besham to Chilas. Intense seismicity, deep gorges, steep terrain and extreme climatic events trigger multiple mountain hazards along the KKH, among which debris flow is recognized as the most destructive geohazard. This study aims to prepare a field-based debris flow inventory map at a regional scale along a 200 km stretch from Besham to Chilas. A total of 117 debris flows were identified in the field, and subsequently, a point-based debris-flow inventory and catchment delineation were performed through Arc GIS analysis. Regional scale debris flow susceptibility and propagation maps were prepared using Weighted Overlay Method(WOM) and Flow-R technique sequentially. Predisposing factors include slope, slope aspect, elevation, Topographic Roughness Index(TRI), Topographic Wetness Index(TWI), stream buffer, distance to faults, lithology rainfall, curvature, and collapsed material layer. The dataset was randomly divided into training data(75%) and validation data(25%). Results were validated through the Receiver Operator Characteristics(ROC) curve. Results show that Area Under the Curve(AUC) using WOM model is 79.2%. Flow-R propagation of debris flow shows that the 13.15%, 22.94%, and 63.91% areas are very high, high, and low susceptible to debris flow respectively. The propagation predicated by Flow-R validates the naturally occurring debris flow propagation as observed in the field surveys. The output of this research will provide valuable input to the decision makers for the site selection, designing of the prevention system, and for the protection of current infrastructure. 展开更多
关键词 north Pakistan Debris flow Flow-R Propagation Susceptibility mapping Debris-flow inventory Weighted Overlay Method
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A Physics-informed Deep-learning Intensity Prediction Scheme for Tropical Cyclones over the Western North Pacific 被引量:1
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作者 Yitian ZHOU Ruifen ZHAN +4 位作者 Yuqing WANG Peiyan CHEN Zhemin TAN Zhipeng XIE Xiuwen NIE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1391-1402,共12页
Accurate prediction of tropical cyclone(TC)intensity is challenging due to the complex physical processes involved.Here,we introduce a new TC intensity prediction scheme for the western North Pacific(WNP)based on a ti... Accurate prediction of tropical cyclone(TC)intensity is challenging due to the complex physical processes involved.Here,we introduce a new TC intensity prediction scheme for the western North Pacific(WNP)based on a time-dependent theory of TC intensification,termed the energetically based dynamical system(EBDS)model,together with the use of a long short-term memory(LSTM)neural network.In time-dependent theory,TC intensity change is controlled by both the internal dynamics of the TC system and various environmental factors,expressed as environmental dynamical efficiency.The LSTM neural network is used to predict the environmental dynamical efficiency in the EBDS model trained using besttrack TC data and global reanalysis data during 1982–2017.The transfer learning and ensemble methods are used to retrain the scheme using the environmental factors predicted by the Global Forecast System(GFS)of the National Centers for Environmental Prediction during 2017–21.The predicted environmental dynamical efficiency is finally iterated into the EBDS equations to predict TC intensity.The new scheme is evaluated for TC intensity prediction using both reanalysis data and the GFS prediction data.The intensity prediction by the new scheme shows better skill than the official prediction from the China Meteorological Administration(CMA)and those by other state-of-art statistical and dynamical forecast systems,except for the 72-h forecast.Particularly at the longer lead times of 96 h and 120 h,the new scheme has smaller forecast errors,with a more than 30%improvement over the official forecasts. 展开更多
关键词 tropical cyclones western north Pacific intensity prediction EBDS LSTM
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Fundamental Character of Anti-Japanese War Cultural Activity
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《中华文化论坛》 北大核心 2015年第7期191-192,共2页
Anti-Japanese War Cultural Activity is the cultural activity full of gunpowder. It is based on the politics, taking the crowed as the object, taking the criticism as the weapon, changing with the times. It hasthe sign... Anti-Japanese War Cultural Activity is the cultural activity full of gunpowder. It is based on the politics, taking the crowed as the object, taking the criticism as the weapon, changing with the times. It hasthe significance of milestone of national cultural activity. 展开更多
关键词 anti-japanese culture activity character.
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A Study on the Loss of Tourist Attractions in Central China Hubei Province During the Anti-Japanese War
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作者 Juying Qiao 《Management Studies》 2020年第5期386-389,共4页
This paper takes the Wudang Mountains and Wuhan Battle Memorial Hall as examples to investigate and analyze the losses of Wuhan during the Anti-Japanese War.The paper concludes with two inspirations:to make full use o... This paper takes the Wudang Mountains and Wuhan Battle Memorial Hall as examples to investigate and analyze the losses of Wuhan during the Anti-Japanese War.The paper concludes with two inspirations:to make full use of the intangible cultural heritage spots to carry out patriotism education for primary and middle school students;and to effectively transform the cultural resources of the tourist spots in Hubei Province into cultural industries,in order to achieve the sustainable development of intangible cultural resources of Hubei Province tourist attractions. 展开更多
关键词 during the anti-japanese War Hubei Province tourist attractions LOSSES
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Genesis of LCT Pegmatites during Early Paleozoic Orogeny of the North Qinling Orogenic Belt,China:Emplacement Conditions and Structural Control 被引量:1
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作者 CEN Jubiao FENG Yonggang +6 位作者 LIANG Ting WANG Mengxi ZHANG Jianxin TAN Xijuan ZHANG Jie GAO Jinggang HE Lei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1226-1243,共18页
The Guanpo pegmatite field in the North Qinling orogenic belt(NQB),China,hosts the most abundant LCT pegmatites.However,their emplacement conditions and structural control remain unexplored.In this contribution,we inv... The Guanpo pegmatite field in the North Qinling orogenic belt(NQB),China,hosts the most abundant LCT pegmatites.However,their emplacement conditions and structural control remain unexplored.In this contribution,we investigated it combining pegmatite orientation measurement with oxygen isotope geothermometry and fluid inclusion study.The orientations of type A1 pegmatites(P_(f)<σ_(2))are predominantly influenced by P-and T-fractures due to simple shearing in Shiziping dextral thrust shear zone during D_(2)deformation,whereas type A2 pegmatites(contemporaneous with D_(4))are governed by hydraulic fractures aligned with S_(0)and S_(0+1)stemming from fluid pressure(P_(f)<σ_(2)).Additionally,type B pegmatites(P_(f)≤σ_(2))exhibit orientations shaped by en echelon extensional fractures in local ductile shear zones(contemporaneous with D_(3)).The albite-quartz oxygen isotope geothermometry and microthermometric analysis of fluid inclusions in elbaites from the latest pegmatites(including types B and A2)suggest that the crystallization P-T for late magmatic and hydrothermal stages are 527.5-559.2℃,320℃,3.1-3.6 kbar and 2.0 kbar,respectively.Our observations along with previous studies suggest that the genesis of the LCT pegmatites was a long-term,multi-stage event during early Paleozoic orogeny(including the collision stage)of the NQB,and was facilitated by various local fractures. 展开更多
关键词 LCT pegmatite emplacement mechanism emplacement condition oxygen isotope geothermometry fluid inclusion north Qinling orogenic belt
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Research on the Winter Study Movement in Shanxi Anti-Japanese Base Area from the Perspective of Mass
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作者 XIN Meng 《Journal of Literature and Art Studies》 2021年第1期43-52,共10页
Playing a major role on social education in Shanxi anti-Japanese base area,the winter study movement is a popular education movement implemented by the Communist Party of China,which takes into consideration the base ... Playing a major role on social education in Shanxi anti-Japanese base area,the winter study movement is a popular education movement implemented by the Communist Party of China,which takes into consideration the base area’s reality and makes full use of the leisure time in winter of rural area.With a wide coverage of education in culture,politics,daily life,anti-Japanese war as well as other aspects.The winter study movement provides efficient education to rural peasants,achieving great effects on mobilization on the masses of the people.This paper focuses on the original archives of the grassroots,conveying comprehensive analysis on the institutional arrangement,organizational mechanism and specific implementation of the winter study movement,thus to provide an overall understanding of the winter study movement in Shanxi anti-Japanese base area from the perspective of mass mobilization. 展开更多
关键词 mass mobilization Shanxi anti-japanese Base Area winter study movement
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The Grass-Roots Governance of the National Government in Tianjin Recovery Area After the Triumph of the Anti-Japanese War
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作者 ZHANG Guopeng 《Cultural and Religious Studies》 2021年第1期20-31,共12页
The national government wants to penetrate into the grass-roots unit after the triumph of the Anti-Japanese War in the recovery area.Through the reorganization of the Baojia system,the government expects to achieve lo... The national government wants to penetrate into the grass-roots unit after the triumph of the Anti-Japanese War in the recovery area.Through the reorganization of the Baojia system,the government expects to achieve local autonomy and then solve the people’s livelihood issues.The new Baojia system provides a platform for people to achieve their own demands,which presents the vision of civil rights to a certain extent.However,because of the complexity of the postwar social environment,the Baojia system cannot completely represent the will of the people,and finally becomes a militarized organization that was used as a tool to carry out the government decree. 展开更多
关键词 after the triumph of the anti-japanese War TIANJIN the grass-roots governance the Baojia system
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Under the Pagoda Mountain:Japanese POW Reformation During the Anti-Japanese War
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作者 LI Jin 《Cultural and Religious Studies》 2019年第4期183-201,共19页
As a typical Lenin-style political party,what should be concerned most is the CPC’s (Communist Party of China) capacity in fighting against and clearing enemies.This study provides a distinct perspective to observe a... As a typical Lenin-style political party,what should be concerned most is the CPC’s (Communist Party of China) capacity in fighting against and clearing enemies.This study provides a distinct perspective to observe and recognize CPC’s ability of turning hostility into friendship.Japanese prisoners of war (POW) had been poisoned by ultra-nationalism and militarism for years,and thus were extremely difficult to be reformed.However,under the correct ideological guidance of Mao and the unremitting efforts of the CPC’s political officers and cadres,a great number of them acknowledged the CPC’s political ideology and joined the CPC’s team. 展开更多
关键词 anti-japanese WAR PRISONER of WAR POLITICAL transformation
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For Permanent Peace—An Introduction to China's Anti-Japanese War Memorial Hall
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《China & The World Cultural Exchange》 1995年第4期12-13,共2页
关键词 An Introduction to China’s anti-japanese War Memorial Hall For Permanent Peace
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Rheological Evidence of the Lithospheric Destruction of the Eastern Block of the North China Craton
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作者 LI Baochun YE Gaofeng +2 位作者 JIN Sheng WEI Wenbo ZHANG Letian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期36-38,共3页
The Eastern Block of the North China Craton(NCC)(Fig.1)has undergone severe lithospheric destruction,with crustal thinning down to 100 km depth(Chen et al.,2009),contrasting sharply with the stable Kalahari and Rae cr... The Eastern Block of the North China Craton(NCC)(Fig.1)has undergone severe lithospheric destruction,with crustal thinning down to 100 km depth(Chen et al.,2009),contrasting sharply with the stable Kalahari and Rae cratons.However,there remains controversy over the destruction pattern(e.g.,Zhu et al.,2017).During the Early Mesozoic,crustal thickening occurred in the Xuhuai and Qinling orogens,followed by lithospheric delamination leading to crustal thinning(Chen et al.,2023).The middle and upper crustal thinning in the Yanshan and Taihang uplifts was induced by mafic magma underplating(Ji et al.,2009). 展开更多
关键词 MAGNETOTELLURICS resistivity viscosity Eastern Block north China Craton
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Comparative Orotomy of the Archean Superior,North China,and Phanerozoic Altaid Orogenic Systems Architecture
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作者 T.M.KUSKY A.M.C.ŞENGÖR 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期33-35,共3页
Geological maps encode vast amounts of data about rock types,ages,chemistry,orogenic architecture and deep-time history or different tectonic units,yet these are often difficult to extract because of the way different... Geological maps encode vast amounts of data about rock types,ages,chemistry,orogenic architecture and deep-time history or different tectonic units,yet these are often difficult to extract because of the way different geologists portray their results at various scales.To understand orogenesis in 4D,it is essential to uniformly integrate map data,together with geophysical data and deep geochemical mapping(Wang et al.,2023). 展开更多
关键词 ARCHEAN comparative tectonics orotomy Superior craton ALTAIDS north China craton
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Stability of the Stratification of Water Bodies in the North Passage of the Yangtze River Estuary Based on the EFDC Model
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作者 WU De’an LI Xin WANG Yigang 《Journal of Ocean University of China》 CAS CSCD 2024年第1期23-32,共10页
To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC res... To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC results,this paper derives and pro-vides the discriminative index of water body stability caused by salinity and analyzes the along-range variation in water body strati-fication stability in the North Passage of the Yangtze River Estuary and the periodic variation at a key location(bend area)based on the simulation results of the numerical model.This work shows that the water body in the bend area varies between mixed and strati-fied types,and the vertical average flow velocity has a good negative correlation with the differential velocity between the surface and bottom layers of the water body.The model simulation results validate the formulae for the stratified stability discriminant during spring tides. 展开更多
关键词 Yangtze Estuary north Passage EFDC model stratification stability salinity distribution
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Assessing climate effects on wheat yield heterogeneity in the North China Plain and evolution from 1960 to 2020
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作者 Yang Han Jinglei Wang Dongmei Qiao 《The Crop Journal》 SCIE CSCD 2024年第6期1791-1800,共10页
This study quantified climate effects on wheat yield heterogeneity in the North China Plain from 1960 to 2020,by integrating the Agricultural Production Systems sIMulator,Optimal Parameters–based Geographical Detecto... This study quantified climate effects on wheat yield heterogeneity in the North China Plain from 1960 to 2020,by integrating the Agricultural Production Systems sIMulator,Optimal Parameters–based Geographical Detector model,and Ensemble Empirical Mode Decomposition model.The factors dominating yield heterogeneity varied by growth stage.For sowing to anthesis,anthesis to maturation,and the entire growth season,minimum temperature,radiation,and vapor pressure deficit has the greatest effect on yield heterogeneity.Interannual periodic oscillations govern the long–term evolution of climate effects on yield heterogeneity from 1960 to 2020. 展开更多
关键词 HETEROGENEITY CLIMATE Wheat production Evolution mechanism north China Plain
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Strong Earthquake Model of North China Craton: A Case of 2023 Mw 5.5 Earthquake in Pingyuan County, Shandong Province, China
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作者 LIU Guanshen LU Renqi +2 位作者 HE Dengfa FANG Lihua ZHANG Yang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期39-40,共2页
North China is one of the high-risk areas for destructive strong earthquakes in China's Mainland, with a history of numerous significant seismic events. On August 6, 2023, an Mw5.5 earthquake struck Pingyuan Count... North China is one of the high-risk areas for destructive strong earthquakes in China's Mainland, with a history of numerous significant seismic events. On August 6, 2023, an Mw5.5 earthquake struck Pingyuan County, Dezhou City, in Shandong Province, China. This earthquake was the largest in the eastern North China Craton(NCC) since the Tangshan earthquake of 1976. Due to the absence of surface ruptures, the fault responsible for the Pingyuan Mw5.5 earthquake remains unclear. To reveal the subsurface geological structure near the earthquake epicenter, this study utilized highresolution two-dimensional seismic reflection profiles to interpret pre-existing faults. 展开更多
关键词 Pingyuan earthquake seismogenic fault relocation earthquakes north China Craton
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Optimization of inter-seasonal nitrogen allocation increases yield and resource-use efficiency in a water-limited wheat-maize cropping system in the North China Plain
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作者 Xiaonan Zhou Chenghang Du +7 位作者 Haoran Li Zhencai Sun Yifei Chen Zhiqiang Gao Zhigan Zhao Yinghua Zhang Zhimin Wang Ying Liu 《The Crop Journal》 SCIE CSCD 2024年第3期907-914,共8页
Winter wheat–summer maize cropping system in the North China Plain often experiences droughtinduced yield reduction in the wheat season and rainwater and nitrogen(N)fertilizer losses in the maize season.This study ai... Winter wheat–summer maize cropping system in the North China Plain often experiences droughtinduced yield reduction in the wheat season and rainwater and nitrogen(N)fertilizer losses in the maize season.This study aimed to identify an optimal interseasonal water-and N-management strategy to alleviate these losses.Four ratios of allocation of 360 kg N ha^(-1)between the wheat and maize seasons under one-time presowing root-zone irrigation(W0)and additional jointing and anthesis irrigation(W2)in wheat and one irrigation after maize sowing were set as follows:N1(120:240),N2(180:180),N3(240:120)and N4(300:60).The results showed that under W0,the N3 treatment produced the highest annual yield,crop water productivity(WPC),and nitrogen partial factor productivity(PFPN).Increased N allocation in wheat under W0 improved wheat yield without affecting maize yield,as surplus nitrate after wheat harvest was retained in the topsoil layers and available for the subsequent maize.Under W2,annual yield was largest in the N2 treatment.The risk of nitrate leaching increased in W2 when N application rate in wheat exceeded that of the N2 treatment,especially in the wet year.Compared to W2N2,the W0N3 maintained 95.2%grain yield over two years.The WPCwas higher in the W0 treatment than in the W2 treatment.Therefore,following limited total N rate,an appropriate fertilizer N transfer from maize to wheat season had the potential of a“triple win”for high annual yield,WPCand PFPN in a water-limited wheat–maize cropping system. 展开更多
关键词 Cropping system Water-saving irrigation north China Plain Nitrogen optimization Sustainable intensification
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Zircon U-Pb geochronologic,geochemical and Sr-Nd-Pb isotope characteristics of the Beidaban granites in the North Qilian Orogenic Belt:Petrogenesis and tectonic implications
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作者 Tao Yang Zhi-yuan Sun +2 位作者 Ming-liang Wang Xiao-qiang Zhu Jing-yu Zhao 《Acta Geochimica》 EI CAS CSCD 2024年第6期1087-1104,共18页
The tectonic evolution and crustal accretion process of the North Qilian Orogenic Belt(NQOB)are still under debate because of a lack of integrated constraints,especially the identifi cation of the tectonic transition ... The tectonic evolution and crustal accretion process of the North Qilian Orogenic Belt(NQOB)are still under debate because of a lack of integrated constraints,especially the identifi cation of the tectonic transition from arc to initial collision.Here we present results from zircon U-Pb geochronology,whole-rock geochemistry,and Sr-Nd-Pb isotope geochemistry of the Beidaban granites to provide crucial information for geodynamic evolution of NQOB.Zircon U-Pb dating yields an age of 468±10 Ma for the Beidaban granites and most of the Beidaban samples contain amphibole,are potassium-rich,and have A/CNK values ranging from 0.7 to 0.9,illustrating that the Middle Ordovician Beidaban granites are K-rich,metaluminous,calc-alkaline granitoid.The geochemical characteristics indicate that the Beidaban granites are transitional I/S-type granitoids that formed in an arc setting.The isotopic compositions of initial(87 Sr/86 Sr)i values ranging from 0.70545 to 0.71082(0.70842 on average)andεNd(t)values ranging from−10.9 to−6.7(−8.8 on average)with two-stage Nd model ages(T DM2)of 1.74-2.08 Ga suggest that the Beidaban granites originated from Paleoproterozoic crustal materials.In addition,the initial Pb isotopic compositions(^(206)Pb/^(204)Pb=19.14-20.26;^(207)Pb/^(204)Pb=15.71-15.77;^(208)Pb/^(204)Pb=37.70-38.26)and geochemical features,such as high Th/Ta(17.43-30.12)and Rb/Nb(6.01-15.49)values,suggest that the Beidaban granite magma source involved recycled crustal components with igneous rocks.Based on these results in combination with previously published geochronological and geochemical data from other early Paleozoic igneous rocks,we suggest that the timing of the tectonic transition from arc to the initial collision to the fi nal closure of the North Qilian Ocean can be constrained to the Middle-Late Ordovician(ca.468–450 Ma). 展开更多
关键词 GRANITOIDS Zircon U-Pb dating Sr-Nd-Pb-isotopes PETROGENESIS north Qilian Orogenic Belt
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Early Devonian Post-collisional Granitic Magmatism in the North Qilian Orogenic Belt,Western China:Insights into Lithospheric Delamination and Orogenic Collapse
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作者 WANG Qian ZHAO Xilin +2 位作者 MENG Yuanku YU Shengyao LIU Yanan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期352-367,共16页
Post-collisional magmatism contains important clues for understanding the reworking and growth of continental crust,as well as lithospheric delamination and orogenic collapse.Early Devonian magmatism has been identifi... Post-collisional magmatism contains important clues for understanding the reworking and growth of continental crust,as well as lithospheric delamination and orogenic collapse.Early Devonian magmatism has been identified in the North Qilian Orogenic Belt(NQOB).This paper reports an integrated study of petrology,whole-rock geochemistry,Sm-Nd isotope and zircon U-Pb dating,as well as Lu-Hf isotopic data,for two Early Devonian intrusive plutons.The Yongchang and Chijin granites yield zircon U-Pb ages of 394-407 Ma and 414 Ma,respectively.Both of them are characterized by weakly peraluminous to metaluminous without typical aluminium-rich minerals,LREE-enriched patterns with negative Eu anomalies and a negative correlation between P_(2)O_(5) and SiO_(2) contents,consistent with geochemical features of I-type granitoids.Zircons from the studied granites display negative to weak positive ε_(Hf)(t)values(−5.7 to 2.1),which agree well with those of negative ε_(Nd)(t)values(−6.4 to−2.9)for the whole-rock samples,indicating that they were derived from the partial melting of Mesoproterozoic crust.Furthermore,low Sr/Y ratios(1.13-21.28)and high zircon saturation temperatures(745℃ to 839℃,with the majority being>800℃)demonstrated a relatively shallow depth level below the garnet stability field and an additional heat source.Taken together,the Early Devonian granitic magmatism could have been produced by the partial melting of ancient crustal materials heated by mantle-derived magmas at high-temperature and low-pressure conditions during postcollisional extensional collapse.The data obtained in this study,when viewed in conjunction with previous studies,provides more information about the tectonic processes that followed the closure of the North Qilian Ocean.The tectonic transition from continental collision to post-collisional delamination could be constrained to~430 Ma,which is provided by the sudden decrease of Sr/Y and La/Yb ratios and an increase in zircon ε_(Hf)(t)values for granitoids.A two-stage tectonic evolution model from continental collision to post-collisional extensional collapse for the NQOB includes(a)continental collision and crustal thickening during ca.455-430 Ma,characterized by granulite-facies metamorphism and widespread low-Mg adakitic magmatism;(b)post-collisional delamination of thickened continental crust and extensional collapse of orogen during ca.430-390 Ma,provided by coeval high-Mg adakitic magmatism,A-type granites and I-type granitoids with low Sr-Y ratios. 展开更多
关键词 post-collisional magmatism lithospheric delamination extensional collapse north Qilian Orogenic Belt
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