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Soft-sediment Deformation Structures Related to Earthquake from the Devonian of the Eastern North Qilian Mts.and Its Tectonic Significance 被引量:13
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作者 DU Yuansheng XU Yajun YANG Jianghai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1185-1193,共9页
Devonian in the North Qilian orogenic belt and Hexi Corridor developed terrestrial molasse of later stage of foreland basin caused by collision between the North China plate and Qaidam microplate. The foreland basin t... Devonian in the North Qilian orogenic belt and Hexi Corridor developed terrestrial molasse of later stage of foreland basin caused by collision between the North China plate and Qaidam microplate. The foreland basin triggered a intense earthquake, and formed seismites and earthquake-related soft-sediment deformation. The soft-sediment deformation structures of Devonian in the eastern North Qilian Mts. consist of seismo-cracks, sandstone dykes, syn-depositional faults, microfoids (micro-corrugated lamination), fluidized veins, load casts, flame structures, pillow structures and brecciation. The seismo-cracks, syn-depositional faults and microfolds are cracks, faults and folds formed directly by oscillation of earthquake. The seismic dykes formed by sediment instilling into seismic cracks. Fluidized veins were made by instilling into the seismo-fissures of the fluidized sands. The load casts, flame structures and pillow structures were formed by sinking and instilling caused from oscillation of earthquake along the face between sandy and muddy beds. The brecciation resulted from the oscillation of earthquake and cracking of sedimentary layers. The seismites and soft-sediment deformations in Devonian triggered the earthquake related to tectonic activities during the orogeny and uplift of North Qilian Mts. 展开更多
关键词 North qilian mts. SEISMITES soft-sediment deformation DEVONIAN TECTONICS
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Evaluation of ERA5 reanalysis temperature data over the Qilian Mountains of China
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作者 ZHAO Peng HE Zhibin 《Journal of Mountain Science》 2025年第1期198-209,共12页
Air temperature is an important indicator to analyze climate change in mountainous areas.ERA5 reanalysis air temperature data are important products that were widely used to analyze temperature change in mountainous a... Air temperature is an important indicator to analyze climate change in mountainous areas.ERA5 reanalysis air temperature data are important products that were widely used to analyze temperature change in mountainous areas.However,the reliability of ERA5 reanalysis air temperature over the Qilian Mountains(QLM)is unclear.In this study,we evaluated the reliability of ERA5 monthly averaged reanalysis 2 m air temperature data using the observations at 17 meteorological stations in the QLM from 1979 to 2017.The results showed that:ERA5 reanalysis monthly averaged air temperature data have a good applicability in the QLM in general(R2=0.99).ERA5 reanalysis temperature data overestimated the observed temperature in the QLM in general.Root mean square error(RMSE)increases with the increasing of elevation range,showing that the reliability of ERA5 reanalysis temperature data is worse in higher elevation than that in lower altitude.ERA5 reanalysis temperature can capture observational warming rates well.All the smallest warming rates of observational temperature and ERA5 reanalysis temperature are found in winter,with the warming rates of 0.393°C/10a and 0.360°C/10a,respectively.This study will provide a reference for the application of ERA5 reanalysis monthly averaged air temperature data at different elevation ranges in the Qilian Mountains. 展开更多
关键词 ERA5 Reanalysis data Air temperature qilian Mountains Climate change
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土壤镉胁迫下龙葵MTs的检测与响应:纳米材料与微生物的影响
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作者 朱丽 刘明洋 +2 位作者 徐晓鸣 王志峰 曹秀凤 《生态毒理学报》 CAS CSCD 北大核心 2024年第6期383-390,共8页
本论文以单纯周芽孢杆菌和卷枝毛霉为供试微生物,以纳米氧化铁为外源添加材料,采用龙葵(Solanum nigrum L.)盆栽实验,以龙葵中金属硫蛋白(MTs)、生物量和土壤-龙葵中镉(Cd)含量的响应差异为指标,研究了土壤Cd胁迫下纳米氧化铁与微生物... 本论文以单纯周芽孢杆菌和卷枝毛霉为供试微生物,以纳米氧化铁为外源添加材料,采用龙葵(Solanum nigrum L.)盆栽实验,以龙葵中金属硫蛋白(MTs)、生物量和土壤-龙葵中镉(Cd)含量的响应差异为指标,研究了土壤Cd胁迫下纳米氧化铁与微生物对龙葵响应机制及修复效果的影响。结果表明,紫外光谱分析方法可快速检测龙葵叶片中MTs含量,其最大吸收峰为317 nm,线性关系良好。MTs测定结果表明,单纯周芽孢杆菌、卷枝毛霉及其联合处理均能有效促进龙葵生成MTs,从而结合更多Cd离子,减轻Cd对植物的毒害,表现为植物生物量的提高和重金属去除率的提升,这与微生物对植物的促生作用相吻合;其中卷枝毛霉对植物的解毒作用尤为突出,相比对照组,龙葵叶片中MTs的含量增加了86.95%,生物量增加了44.59%,叶片中Cd含量增加了47.26%。不同的是,单独纳米氧化铁的添加未显著影响龙葵中MTs的含量。 展开更多
关键词 镉(CD) 龙葵 植物解毒 土壤修复 纳米氧化铁 金属硫蛋白(mts)
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产教融合背景下基于MTS理论的金融知识学习及教学模式研究
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作者 闫举纲 牛心如 《财务管理研究》 2024年第9期150-157,共8页
在产教融合背景下,金融类课程的教学模式正向问题导向型转变。金融知识学习及教学通过产学协同,并匹配不同学生的学习特征和所要传授的知识特征,实现人才培养质量的提升。产教融合的模式中,混合型师资队伍建设是核心环节,通过案例研究,... 在产教融合背景下,金融类课程的教学模式正向问题导向型转变。金融知识学习及教学通过产学协同,并匹配不同学生的学习特征和所要传授的知识特征,实现人才培养质量的提升。产教融合的模式中,混合型师资队伍建设是核心环节,通过案例研究,基于多团队系统理论,探讨产教融合背景下如何构建由校内教师、行业专家和学生组成的多元化教学团队,并分析其运行机制和效果;同时,基于学习模型的教学支持与模式创新,结合学生学习特征,对主要教学方法进行体系化梳理,并优化教学方法,形成教学方案。 展开更多
关键词 多团队系统(mts) 金融知识 学习模型 教学模式
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FROM BACK-ARC BASIN TO BACK-ARC FORELAND BASIN—THE SEDIMENTARY BASIN AND TECTONIC EVOLUTION OF THE LATE CALEDONIAN—EARLY HERCYNIAN STAGES IN CORRIDOR AND NORTH QILIAN MTS 被引量:1
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作者 Du Yuansheng, Gong Shuyun, Han Xin, Wang Jiasheng, Hou Guangjiu(Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074,China) 《地学前缘》 EI CAS CSCD 2000年第S1期252-253,共2页
Qilian orogenic belt is a typical orogenic belt formed by polycyclic collisions between the North China plate and Qaidam microplate. Qilian ocean originated from the rift of the late Proterozoic Rodinia continent(Pang... Qilian orogenic belt is a typical orogenic belt formed by polycyclic collisions between the North China plate and Qaidam microplate. Qilian ocean originated from the rift of the late Proterozoic Rodinia continent(Pangea\|850), evolved through rift basin and became an archipelagic ocean in the Caledonian stage. The Lower Proterozoic strata in Qilian area are mid\|high\|rank metamorphic rocks that constitute the metamorphic basement of the area. The “Huangyuan Movement" (in South Qilian and Central Qilian) and "Alashan Movement" (in North Qilian) in the latest Late Proterozoic formed a regional unconformity. The middle Proterozoic in the area are mudstones and carbonate rocks with stromatolites and ooids. The Qingbaikou System of the upper Proterozoic in the North Qilian and Corridor region is also mudstone and carbonate rock with stromatolites. The Qingbaikou System in Central Qilian is sandstones and mudstones. There are alkaline and tholeiite in the Sinian System in North Qilian and Corridor. The contact between Qingbaikou System and Sinian System is a regional unconformity (Quanji Movement). Qilian ocean began to rift away in Caledonian tectonic stage on the Pre\|Sinian basement. 展开更多
关键词 sedimentary BASIN tectonic evolution LATE Caledon ian EARLY HERCYNIAN North qilian mts. CORRIDOR
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Differential response of radial growth and δ^(13)C in Qinghai spruce(Picea crassifolia) to climate change on the southern and northern slopes of the Qilian Mountains in Northwest China 被引量:1
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作者 Li Qin Huaming Shang +4 位作者 Weiping Liu Yuting Fan Kexiang Liu Tongwen Zhang Ruibo Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期205-218,共14页
Tree radial growth can have significantly differ-ent responses to climate change depending on the environ-ment.To elucidate the effects of climate on radial growth and stable carbon isotope(δ^(13)C)fractionation of Q... Tree radial growth can have significantly differ-ent responses to climate change depending on the environ-ment.To elucidate the effects of climate on radial growth and stable carbon isotope(δ^(13)C)fractionation of Qing-hai spruce(Picea crassifolia),a widely distributed native conifer in northwestern China in different environments,we developed chronologies for tree-ring widths and δ^(13)C in trees on the southern and northern slopes of the Qilian Mountains,and analysed the relationship between these tree-ring variables and major climatic factors.Tree-ring widths were strongly influenced by climatic factors early in the growing season,and the radial growth in trees on the northern slopes was more sensitive to climate than in trees on the southern.Tree-ring δ^(13)C was more sensitive to climate than radial growth.δ^(13)C fractionation was mainly influenced by summer temperature and precipitation early in the growing season.Stomatal conductance more strongly limited stable carbon isotope fractionation in tree rings than photosynthetic rate did.The response between tree rings and climate in mountains gradually weakened as climate warmed.Changes in radial growth and stable carbon isotope fractionation of P.crassifolia in response to climate in the Qilian Mountains may be further complicated by continued climate change. 展开更多
关键词 Tree rings Qinghai spruce(Picea crassifolia Kom.) Stable carbon isotope(δ^(13)C) qilian Mountains:Climate change
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Temperature trends and its elevation-dependent warming over the Qilian Mountains
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作者 ZHAO Peng HE Zhibin +2 位作者 MA Dengke WANG Wen QIAN Lihui 《Journal of Mountain Science》 SCIE CSCD 2024年第2期500-510,共11页
Understanding temperature variability especially elevation dependent warming(EDW)in high-elevation mountain regions is critical for assessing the impacts of climate change on water resources including glacier melt,deg... Understanding temperature variability especially elevation dependent warming(EDW)in high-elevation mountain regions is critical for assessing the impacts of climate change on water resources including glacier melt,degradation of soils,and active layer thickness.EDW means that temperature is warming faster with the increase of altitude.In this study,we used observed temperature data during 1979-2017 from 23 meteorological stations in the Qilian Mountains(QLM)to analyze temperature trend with Mann-Kendall(MK)test and Sen’s slope approach.Results showed that the warming trends for the annual temperature followed the order of T_min>T_mean>T_max and with a shift both occurred in 1997.Spring and summer temperature have a higher increasing trend than that in autumn and winter.T_mean shifts occurred in 1996 for spring and summer,in 1997 for autumn and winter.T_max shifts occurred in 1997 for spring and 1996 for summer.T_min shifts occurred in 1997 for spring,summer and winter as well as in 1999 for autumn.Annual mean diurnal temperature range(DTR)shows a significant decreasing trend(-0.18°C/10a)from 1979 to 2017.Summer mean DTR shows a significant decreasing trend(-0.26°C/10a)from 1979 to 2017 with a shift occurred in 2010.After removing longitude and latitude factors,we can learn that the warming enhancement rate of average annual temperature is 0.0673°C/km/10a,indicating that the temperature warming trend is accelerating with the continuous increase of altitude.The increase rate of elevation temperature is 0.0371°C/km/10a in spring,0.0457°C/km/10a in summer,0.0707°C/km/10a in autumn,and 0.0606°C/km/10a in winter,which indicates that there is a clear EDW in the QLM.The main causes of warming in the Qilian Mountains are human activities,cloudiness,ice-snow feedback and El Nino phenomenon. 展开更多
关键词 Climate change qilian Mountains Warming rates DTR Elevation-dependent warming
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Tectonic framework of Qilian orogen: reveal from an aeromagnetic anomaly feature
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作者 Yang Hai Xiong Shengqing +7 位作者 Liu Qiankun Zhou Daoqing Yang Xue Fan Zhengguo Jia Zhiye Li fang Gao xiuhe Liu fuxiang 《Applied Geophysics》 SCIE CSCD 2024年第3期528-548,618,619,共23页
The Qilian Orogenic belt is one of the typical orogenic belts globally and a natural laboratory for studying plate tectonics.Many researchers have studied the ophiolite and high pressure and ultra-high pressure metamo... The Qilian Orogenic belt is one of the typical orogenic belts globally and a natural laboratory for studying plate tectonics.Many researchers have studied the ophiolite and high pressure and ultra-high pressure metamorphic rocks in the Qilian orogen and obtained valuable achievements.However,a hot debate exists on the basement property,the distribution of ophiolite,and the boundaries of tectonic units.Large-scale high-precision aeromagnetic surveys have recently been conducted in the Qilian Orogenic belt and adjacent areas.In this study,we are trying to analysis the tectonic framework of the Qilian Orogen using 1:500,000 aeromagnetic data.The results provide geophysical perspectives for studying the structural framework and deformation of this area.According to the aeromagnetic∆T anomaly map,the central and Southern Qilian have the same magnetic anomaly feature that noticeably differs from the North Qilian Orogenic belt and the Qaidam Block.This result indicates that the central and Southern Qilian have a unified magnetic basement and differ from the North Qilian orogenic belt and Qaidam Block.The map shows the distribution of ophiolite in the North Qilian orogenic belt.Linear magnetic anomalies represent the ophiolites because the mafic–ultramafic rocks usually have high magnetic susceptibility.The ophiolite belts are continuously distributed in the western part of North Qilian orogenic belt and have a large scale.However,the scale of the ophiolite belt and the outcropping of mafic–ultramafic rocks reduces when they pass through Qilian County to the east.The results indicate differences in the evolution process between the eastern and western parts of North Qilian,with Qilian County as the transition zone.This study also systematically defines the geophysical boundaries of the Qaidam Block,Qilian Block,North Qilian Orogenic belt,and Alxa block.It is proposed that the sinistral displacement of the Altun Fault is adjusted and absorbed by the series of NE-trending faults in the Qilian orogen and merge into the Longshoushan–Gushi Fault.The extension of the North Qilian Orogenic belt is strengthened by the neotectonics movement along the shearing direction,which separated the North Qilian Orogenic belt into several segments and formed a series of northeast-trending faults. 展开更多
关键词 qilian orogen tectonic framework aeromagnetic anomaly feature mafic–ultramafic
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Petrogenesis and tectonic implications of the Silurian adakitic granitoids in the eastern segment of the Qilian Orogenic Belt,Northwest China
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作者 Jiao-Long Zhao Xiao-Jun Huang +5 位作者 Pei-Qing Hu Zhen-Xi Yang Ying Fan Er-Teng Wang Fu-Bo Yang Jing-Yu Zhang 《Acta Geochimica》 EI CAS CSCD 2024年第1期72-86,共15页
Geodynamic mechanism responsible for the generation of Silurian granitoids and the tectonic evolution of the Qilian orogenic belt remains controversial. In this study, we report the results of zircon U–Pb age, and sy... Geodynamic mechanism responsible for the generation of Silurian granitoids and the tectonic evolution of the Qilian orogenic belt remains controversial. In this study, we report the results of zircon U–Pb age, and systematic whole-rock geochemical data for the Haoquangou and Liujiaxia granitoids within the North Qilian orogenic belt and the Qilian Block, respectively, to constrain their petrogenesis, and the Silurian tectonic evolution of the Qilian orogenic belt. Zircon U–Pb ages indicate that the Haoquangou and Liujiaxia intrusions were emplaced at423 ± 3 Ma and 432 ± 4 Ma, respectively. The Haoquangou granodiorites are calc-alkaline, while the Liujiaxia granites belong to the high-K calc-alkaline series.Both are peraluminous in composition and have relatively depleted Nd isotopic [ε_(Nd)(t) =(-3.9 – + 0.6)] characteristics compared with regional basement rocks, implying their derivation from a juvenile lower crust. They show adakitic geochemical characteristics and were generated by partial melting of thickened lower continental crust. Postcollisional extensional regime related to lithospheric delamination was the most likely geodynamic mechanism for the generation of the Haoquangou granodiorite, while the Liujiaxia granites were generated in a compressive setting during continental collision between the Qaidam and Qilian blocks. 展开更多
关键词 Silurian adakitic granitoids PETROGENESIS Tectonic setting 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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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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Vegetation characteristics and soil properties of artificially remediated grasslands:The case study of the Shimenhe mining area in Qilian Mountains,northwest China
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作者 XiaoMei Yang Qi Feng Meng Zhu 《Research in Cold and Arid Regions》 CSCD 2024年第4期190-200,共11页
The mining of limestone mines plays a crucial role in societal and economic advancement.However,mining activities have led to destructive variations in grassland ecology and soil,causing numerous environmental problem... The mining of limestone mines plays a crucial role in societal and economic advancement.However,mining activities have led to destructive variations in grassland ecology and soil,causing numerous environmental problems,and effective artificial restoration measures have been used to restore grasslands in the Shimenhe mining areas to different degrees.In this study,we investigated,examined and analyzed plant community structure and its correlation with soil properties across varying degrees of alpine grassland restoration in Qilian Mountains Shimenhe restoration mines using the sample method,and studied the changes in species diversity using five diversity indexes(Simpson index,Shannon index,Margalef index,Dominance index and Evenness index).This study showed that the plant community characteristics with high recovered degree(HRD)> middle recovered degree(MRD)> low recovered degree(LRD)> very low recovered degree(VLRD),11 plant genera comprising 11 species across 10 families were identified.Dominant families with robust ecological adaptability included Leguminosae,Rosaceae,Gramineae,Asteraceae,and Salicaceae.The highest Simpson,Shannon,Margalef and Evenness index of HRD grassland community species were 0.82,1.96,1.66 and 0.89,respectively.The highest Dominance index of VLRD grassland community species was 0.34,which required several restoration methods such as spraying and mulching.Soil pH and EC tended to decrease with increasing restoration,SOC,SMC,TP,AP,NH4-N,TN,AN and NO3-N tended to increase and the content of soil environmental factors contributed to vegetation growth across various restoration levels the mine grassland.In conclusion,our study indicated that the community structure gradually diversified and soil properties changed positively with the increase of restoration degrees in the Qilian Mountains Shimenhe mine,and the best results of HRD restoration were obtained.This study provides the theoretical basis for the restoration and conservation of grasslands in mining areas by demonstrating examined the correlation between plant characteristics and soil properties in restored grasslands in alpine mining areas. 展开更多
关键词 Alpine mining area grassland Grassland ecosystem Mine restoration Plant characteristics Soil properties qilian mountains
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Finer topographic data improves distribution modeling of Picea crassifolia in the northern Qilian Mountains
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作者 ZHANG Xiang GAO Linlin +3 位作者 LUO Yu YUAN Yiyun MA Baolong DENG Yang 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3306-3317,共12页
The Qilian Mountains, a national key ecological function zone in Western China, play a pivotal role in ecosystem services. However, the distribution of its dominant tree species, Picea crassifolia (Qinghai spruce), ha... The Qilian Mountains, a national key ecological function zone in Western China, play a pivotal role in ecosystem services. However, the distribution of its dominant tree species, Picea crassifolia (Qinghai spruce), has decreased dramatically in the past decades due to climate change and human activity, which may have influenced its ecological functions. To restore its ecological functions, reasonable reforestation is the key measure. Many previous efforts have predicted the potential distribution of Picea crassifolia, which provides guidance on regional reforestation policy. However, all of them were performed at low spatial resolution, thus ignoring the natural characteristics of the patchy distribution of Picea crassifolia. Here, we modeled the distribution of Picea crassifolia with species distribution models at high spatial resolutions. For many models, the area under the receiver operating characteristic curve (AUC) is larger than 0.9, suggesting their excellent precision. The AUC of models at 30 m is higher than that of models at 90 m, and the current potential distribution of Picea crassifolia is more closely aligned with its actual distribution at 30 m, demonstrating that finer data resolution improves model performance. Besides, for models at 90 m resolution, annual precipitation (Bio12) played the paramount influence on the distribution of Picea crassifolia, while the aspect became the most important one at 30 m, indicating the crucial role of finer topographic data in modeling species with patchy distribution. The current distribution of Picea crassifolia was concentrated in the northern and central parts of the study area, and this pattern will be maintained under future scenarios, although some habitat loss in the central parts and gain in the eastern regions is expected owing to increasing temperatures and precipitation. Our findings can guide protective and restoration strategies for the Qilian Mountains, which would benefit regional ecological balance. 展开更多
关键词 Species distribution modeling Picea crassifolia High resolution topographic data Climate change qilian Mountains Nature Reserve Climate scenarios
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Assessment of sediment connectivity using modelling and field-based approaches in the Slavíč River catchment(MoravskoslezskéBeskydy Mts,Czech Republic)
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作者 MACUROVÁ Tereza ŠKARPICH Václav 《Journal of Mountain Science》 SCIE CSCD 2024年第3期734-753,共20页
Mountain streams act as conveyors of sediments within the river continuum,where the physical transport of sediments between river reaches through the catchment or between individual parts(e.g.,between hillslopes and c... Mountain streams act as conveyors of sediments within the river continuum,where the physical transport of sediments between river reaches through the catchment or between individual parts(e.g.,between hillslopes and channels)of the catchment is assumed.This study focused on sediment connectivity analysis in the SlavíčRiver catchment in the MoravskoslezskéBeskydy Mts in the eastern part of the Czech Republic.The connectivity index and connectivity index target modelling were combined with an analysis of anthropogenic interventions.Additionally,field mapping,grain size of bed sediments and stream power analysis were used to obtain information about connectivity in the catchment.Based on the analysis and obtained results,terrain topography is the current main driving factor affecting the connectivity of sediment movement in the SlavíčRiver catchment.However,the modelling provided valuable information about high sediment connectivity despite different recent land use conditions(highly forested area of the catchment)than those in historical times from the 16th to 19th centuries when the SlavíčRiver catchment was highly deforested and sediment connectivity was probably higher.The analysis of anthropogenic interventions,field mapping,grain size of bed sediments and stream power analysis revealed more deceleration of sediment movement through the catchment,decreased sediment connectivity with bed erosion,and gradual river channel process transformation in some reaches.Field mapping has identified various natural formations and human-induced changes impacting the longitudinal and lateral connectivity in the SlavíčRiver.For instance,embankments along 48%of the river's length,both on the right and left banks,significantly hinder lateral sediment supply to the channel.Stream power index analysis indicates increased energy levels in the flowing water in the river's upper reaches(up to 404.8 W m^(-2)).This high energy is also observed in certain downstream sections(up to 337.6 W m^(-2)),where it is influenced by human activities.These conditions lead to intensified erosion processes,playing a crucial role in sediment connectivity.Similar observations were described in recent studies that pointed out the long-term human interventions on many streams draining European mountains,where a decrease in sediment connectivity in these streams is linked with sediment deficits and the transformation of processes forming channels. 展开更多
关键词 Mountain stream Connectivity analysis MODELLING Grain size analysis SlavíčRiver MoravskoslezskéBeskydy mts
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基于MTS-BiGRU-DMHSA的工业负荷预测方法
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作者 王汝英 马嘉骏 +4 位作者 董建强 刘万龙 张海涛 尹凯 赵博超 《计算机工程》 CAS CSCD 北大核心 2024年第9期169-178,共10页
工业用电占我国全社会用电量比重大,通过工业负荷预测了解负荷趋势和用电量信息,有助于电网安全稳定运行,为电力部门发电规划提供依据,且有助于工业用户优化生产工艺和降低成本。为了兼顾工业负荷波动的不确定性以及工业用户用电行为的... 工业用电占我国全社会用电量比重大,通过工业负荷预测了解负荷趋势和用电量信息,有助于电网安全稳定运行,为电力部门发电规划提供依据,且有助于工业用户优化生产工艺和降低成本。为了兼顾工业负荷波动的不确定性以及工业用户用电行为的规律性特征,提出一种基于多时间尺度(MTS)特征的工业负荷预测方法MTS-BiGRU-DMHSA,利用MTS特征融合挖掘工业负荷的周期趋势特征和局部波动特征,提升工业负荷表征的可解释性。此外,双层多头自注意力(DMHSA)机制利用注意力权重聚焦重要特征,在挖掘输入特征关联性的同时捕捉时序关联性,强化重要特征变量与关键时间步的信息表达。在中国某工业企业五面受总柜实采数据上完成实验验证,采用2种评价指标对所提方法及5种基于神经网络的预测方法进行对比分析。实验结果表明,所提方法相较于对比方法平均误差降低逾20%,其中4.67%得益于对MTS特征的运用。通过对比各方法计算效率证实了所提方法的综合性能优势,可视化实验结果与对比分析也验证了其在工业负荷预测任务上的可行性。 展开更多
关键词 工业负荷预测 神经网络 多时间尺度特征 注意力机制 时间序列分析
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MTS及MTO混合生产模式下的宠物用品库存研究
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作者 秦力伟 《中文科技期刊数据库(文摘版)社会科学》 2024年第5期0108-0111,共4页
本文探讨了宠物行业供应链管理的挑战和机遇,强调了采用创新生产战略应对动态市场环境的重要性。本研究首先探讨了传统供应链面临的挑战,包括信息滞后和系统不完整,强调了这些缺陷对决策过程的影响。然后,文章提出采用 MTS/MTO 混合生... 本文探讨了宠物行业供应链管理的挑战和机遇,强调了采用创新生产战略应对动态市场环境的重要性。本研究首先探讨了传统供应链面临的挑战,包括信息滞后和系统不完整,强调了这些缺陷对决策过程的影响。然后,文章提出采用 MTS/MTO 混合生产模式作为战略解决方案,并阐明了每种方法的特点和优势。此外,文章还讨论了 MTS 和 MTO 对不同产品类别和细分市场的适用性,强调了差异化运营战略的必要性。最后,文章的结论强调了持续投资于技术、协作和供应链优化对于宠物行业保持竞争力和满足不断变化的消费者需求的重要意义。 展开更多
关键词 宠物行业供应链 面临挑战 mts/MTO 混合生产模式 运营战略
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MTS-05 PDM多频代播机核心技术及应用
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作者 方少青 《电视技术》 2024年第7期144-146,150,共4页
深入探讨MTS-05 PDM 5 kW多频代播机的研发背景、核心技术、应用价值及其对广播技术领域的影响。在中波广播技术面临频率固定性和调频机制局限的挑战背景下,MTS-05 PDM 5 kW多频代播机作为技术创新的产物,通过集成复杂可编程逻辑器件(Co... 深入探讨MTS-05 PDM 5 kW多频代播机的研发背景、核心技术、应用价值及其对广播技术领域的影响。在中波广播技术面临频率固定性和调频机制局限的挑战背景下,MTS-05 PDM 5 kW多频代播机作为技术创新的产物,通过集成复杂可编程逻辑器件(Complex Programmable Logic Device,CPLD)逻辑频率选通技术、直接数字合成(Direct Digital Synthesizer,DDS)高频激励机制和智能多频网络切换技术,实现了多频次高效、安全播出。设备不仅克服了传统发射机的调频烦琐和空间限制问题,还提升了播出质量和安全播出效率,展示了智能化运维与资源优化的典范。 展开更多
关键词 mts-05 PDM 5 kW多频代播机 高频激励机制 多频网络切换 智能监控管理
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测定淋巴细胞增殖的MTS和XTT比色法的建立 被引量:33
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作者 宋锦平 钟萍 +2 位作者 汪涛 温秀兰 张虹 《细胞与分子免疫学杂志》 CAS CSCD 北大核心 2001年第3期292-295,共4页
目的建立用新型四唑氮盐MTS和XTT做比色分析测定淋巴细胞增殖效应的方法。方法分别用MTS、XTT结合PMS,对小鼠脾淋巴细胞密度和增殖进行比色测定,选择最佳实验条件,并将这两种方法与3H-TdR掺入法和MTT法比较。结果用MTS和XTT比色分析法... 目的建立用新型四唑氮盐MTS和XTT做比色分析测定淋巴细胞增殖效应的方法。方法分别用MTS、XTT结合PMS,对小鼠脾淋巴细胞密度和增殖进行比色测定,选择最佳实验条件,并将这两种方法与3H-TdR掺入法和MTT法比较。结果用MTS和XTT比色分析法测定小鼠脾淋巴细胞的增殖,在0.5~4×109/L的范围内,所获光吸收(A)值与细胞密度呈良好的相关性。最佳细胞密度为2×109/L,最佳反应时间为6h,最佳PMS的终浓度为1×10-4mol/L。两种比色法与3H-TdR掺入法的结果相一致,且两种新方法较MTT法灵敏。结论MTS和XTT比色分析法可代替3H-TdR掺入法和MTT法,用于测定淋巴细胞的增殖效应。 展开更多
关键词 mts XIT 淋巴细胞增殖 测定 比色法
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MTS控制系统的二次开发及其在混合试验中的应用 被引量:10
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作者 王贞 王照然 +3 位作者 杨婧 杨格 吴斌 欧进萍 《地震工程与工程振动》 CSCD 北大核心 2015年第2期22-29,共8页
混合试验将物理实验与数值模拟相结合,大大降低了对加载系统的要求,可以完成大比例尺甚至足尺试验,且方便观察试件的地震响应过程,因此广受关注。为了推进混合试验方法的研究与应用,哈尔滨工业大学吴斌教授课题组正在开发一款混合试验平... 混合试验将物理实验与数值模拟相结合,大大降低了对加载系统的要求,可以完成大比例尺甚至足尺试验,且方便观察试件的地震响应过程,因此广受关注。为了推进混合试验方法的研究与应用,哈尔滨工业大学吴斌教授课题组正在开发一款混合试验平台,即HyTest。本文针对常用的MTS电液伺服系统,采用MTS提供的VB软件接口开发了HyTest试验平台与MTS控制系统的通信模块,具备发送命令、保存数据、坐标变换、网络通信等功能。完成了一例单层单跨6自由度平面钢框架结构混合试验,验证了该通信模块的有效性。重点介绍所使用的开发方法及其在混合试验中的应用,既方便同行使用HyTest,又可作为MTS系统二次开发的借鉴。 展开更多
关键词 混合试验 拟动力试验 mts 二次开发 HyTest
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CCK-8和MTS法检测人羊膜上皮细胞增殖的比较 被引量:15
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作者 刘艳秋 张可华 +10 位作者 王运良 舒峻 来薛 吴立群 曹善霞 李鸿 徐扬 高艳 崔晓惠 左和鸣 蔡哲 《中国康复理论与实践》 CSCD 北大核心 2012年第9期827-830,共4页
目的探讨CCK-8、MTS两种不同的四唑盐试剂在羊膜上皮细胞增殖检测中的最适实验条件,并比较两者细胞毒性。方法取体外培养对数生长期羊膜上皮细胞,用完全培养基(DMEM/F12+10%胎牛血清)配制成不同浓度的细胞悬液加入96孔板中培养24 h,... 目的探讨CCK-8、MTS两种不同的四唑盐试剂在羊膜上皮细胞增殖检测中的最适实验条件,并比较两者细胞毒性。方法取体外培养对数生长期羊膜上皮细胞,用完全培养基(DMEM/F12+10%胎牛血清)配制成不同浓度的细胞悬液加入96孔板中培养24 h,分别加入CCK-8、MTS后于450 nm、492 nm波长处测定光密度(OD)。在同一细胞浓度下,根据同一波长不同时间检测的OD确定CCK-8的最佳孵育时间。取体外培养的对数生长期羊膜上皮细胞分别用DMSO、CCK-8、MTS处理1 h、2 h、3 h和4 h后,继续培养24 h,在450 nm处以CCK-8检测细胞增殖,并通过台盼蓝染色计数活细胞数。结果 CCK-8法的最佳波长为450 nm,MTS法的最佳波长为492 nm。CCK-8法灵敏度稍低于MTS法。1~4 h内,CCK-8试剂与待检测细胞最佳孵育时间为4 h。CCK-8法对细胞增殖影响及细胞毒性均小于MTS法。结论 CCK-8法是一种更为方便、细胞毒性作用较小的试剂。 展开更多
关键词 mts CCK-8 羊膜上皮细胞 细胞增殖 细胞毒性
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