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一个与Mises轨迹覆盖面积相等的线性屈服条件 被引量:2
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作者 赵德文 方琪 +1 位作者 刘相华 王国栋 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2005年第3期248-251,共4页
在π平面上,取Mises屈服轨迹覆盖面积与其相交十二边形覆盖面积相等的方法确定十二边形6个顶点,顶点与内接点连线为新的屈服轨迹,建立该轨迹在HaighWestergaard应力空间上的直线方程,证明了此方程确定的屈服准则为Mises屈服准则的最大... 在π平面上,取Mises屈服轨迹覆盖面积与其相交十二边形覆盖面积相等的方法确定十二边形6个顶点,顶点与内接点连线为新的屈服轨迹,建立该轨迹在HaighWestergaard应力空间上的直线方程,证明了此方程确定的屈服准则为Mises屈服准则的最大程度的线性逼近,其偏差应力矢量模长与Mises准则模长在π平面上平均误差为零;给出了十二边形内接点顶角为159 836°,圆外顶角为140 164°;以及单位体积塑性功率表达式· 展开更多
关键词 线性逼近 Mires屈服准则 π平面 积分中值定理 最高精度 塑性功率
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用Mises屈服条件求简支圆板在线性和均布荷载共同作用下的极限荷载 被引量:3
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作者 陈钢 洪媛 《辽宁大学学报(自然科学版)》 CAS 2004年第4期302-305,共4页
应用Mises屈服条件分析简支圆板在线性荷载和均布荷载共同作用下的极限荷载,并选择不同的试函数,给出极限荷载的变化范围.
关键词 Mires屈服条件 加权余量法 圆板 线性荷载 均布荷载 极限荷载
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Analysis of Mine Environmental Protection and Restoration Management
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作者 Hengrui Chang 《环境科学前沿(中英文版)》 2022年第1期1-4,共4页
In humnan suvival and development,mineal resources ane n inportant puazantee.Minenal resouces play皿estemely important role in ecomomumic development and social progess Mineral resources ae a kind of non-renewable res... In humnan suvival and development,mineal resources ane n inportant puazantee.Minenal resouces play皿estemely important role in ecomomumic development and social progess Mineral resources ae a kind of non-renewable resources.The contimuous exploitation of mineral resources has led to more and more seious damage to the geological envinorment,which in tum has led to the problem of sbortage of mieral resources.I the mining process will also cause damage to the environment,which seniously affects the ecological sabilty.So far,the inareasing awareness of emvironmeantal protection and the rapid economic development n China have put the geological protection of mies on the agenda This paper willl focus on the mangement of mine enviroumental protection and restoration. 展开更多
关键词 miring Enironments Protecton Ecological Problems Restoration Manqgeme
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Dynamics of dissolved organic carbon in the mires in the Sanjiang Plain,Northeast China 被引量:5
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作者 Yuedong Guo Zhongmei Wan Deyan Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第1期84-90,共7页
Mires in boreal area had proved to be an important dissolved organic carbon (DOC) reserve for the sensitivity to climate change and human interfering. The study was focused on the temporal and spatial dynamics and c... Mires in boreal area had proved to be an important dissolved organic carbon (DOC) reserve for the sensitivity to climate change and human interfering. The study was focused on the temporal and spatial dynamics and controlling factors of DOC in a seasonallywaterlogged mire (SLM) and perennially-waterlogged mire (PLM) in the Sanjiang Plain, Northest China. In the two mires, DOC concentrations in both surface water and upper soil strata experienced pronounced seasonal variation. DOC concentrations in the surface waters were the greatest and averagely was 47.82 in SLM and 34.84 mg/L and PLM, whereas that in soil water at 0.3-m depth had little difference (20.25 mg/L in SLM and 26.51 mg/L in PLM). Results revealed that DOC concentrations declined 5-8 times vertically from the surface down to groundwater. DOC in the groundwater only was in a very small part with the average concentration of 5.18 mg/L. In relation to the surface water, DOC concentrations varied positively with temperature just before 8 August, and only in early spring and later autumn DOC concentrations exhibited identifiable spatial trends along with standing water depths in PLM. It was supposed that the influences from standing water depth took effect only in conditions of low temperature, and temperature should be the most powerful factor controlling DOC dynamics in the mires. Redox potential (Red) showed negative relationship with DOC values while total nitrogen (TN) and the majority of free ions in the soil solution exhibited no relationship. High soil TOC/TN ratio and low redox potentials also led to DOC accumulation in the mires in the Sanjiang Plain. 展开更多
关键词 dissovled organic carbon seasonal dynamics MIRES the Sanjiang Plain
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Early Snowmelt Enhances the Carbon Sequestration of Hummock-Forming Sphagnum Mosses on Boreal Wetlands 被引量:1
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作者 Niko Silvan Kari Jokinen 《Open Journal of Ecology》 2016年第3期103-112,共10页
Sphagnum mosses are globally important owing to their considerable peat-forming ability and their potential impact on global climatic cycles acting as a long-term net carbon sink. However, changes in climatic conditio... Sphagnum mosses are globally important owing to their considerable peat-forming ability and their potential impact on global climatic cycles acting as a long-term net carbon sink. However, changes in climatic conditions due to global warming may affect the relations between Sphagnum mosses and vascular plants but also the competition among Sphagnum, and thus alter the accumulation of carbon on boreal wetlands. Sphagnum mosses are a plant genus with a favorable ability to grow in low solar irradiance and temperature conditions compared to vascular plants. This may be increasingly beneficial in increased wintertime temperatures and predated snowmelt conditions. To understand particularly the importance of early spring photosynthetic activity and thus the role of the length of growing season on carbon balance, we analyzed the CO<sub>2</sub> exchange of Sphagnum mosses with closed chamber technique in two categories of microtopographical habitats, hummocks and lawns, during four seasons 2010-2013 on a raised bog in Central Finland. During CO<sub>2</sub> exchange measurements, instantaneous net ecosystem exchange (NEE) and ecosystem respiration (RE) were measured. Our results show that the mean measured seasonal NEE, i.e. the instantaneous net carbon sequestration, of hummocks was generally only slightly higher than the NEE of lawns, but the mean measured seasonal RE of hummocks was clearly and significantly higher than the RE of lawns in every study year. A reason for the observed still higher seasonal carbon sequestration of hummocks than that of lawns besides the slightly higher rate of carbon accumulation was the longer duration of physiologically active growing season. Therefore, hummock-forming Sphagnum mosses exposed firstly from snow cover showed to get the extra time for photosynthesis and thus extra benefit compared to other mire plants. This may be further enhanced by the expansion of hummock-forming Sphagnum moss dominated raised bogs towards northern aapa-mire region due to the global warming. 展开更多
关键词 Sphagnum Mosses Boreal Wetlands Mire Microtopography Carbon Dynamics Global Warming
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THE MIRE IN NORTHEAST OF CHINA
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作者 张养贞 牛焕光 《Chinese Geographical Science》 SCIE CSCD 1993年第3期48-56,共9页
The northeast region is one of the principal mire distribution regions in China. According to the process of peat formation and accumulation , middle geomorphology type controlling water source supplement and the plan... The northeast region is one of the principal mire distribution regions in China. According to the process of peat formation and accumulation , middle geomorphology type controlling water source supplement and the plant cover, 2 types, 10 subtypes and 27 mire bodies are divided. The mire area decreases gradually from north to south. There is more peat mire in the mountain and there is mainly gley mire without peat in the plain. The paper also explains the mire types in the principal mire distribution region and the utilization of mire in the fields of agriculture, forest, animal husbandry. The mire is a wetland ecosystem. It can reserve a lot of water, adjust rivers, humidify air. Thereby , attention must be paid to protecting ecological balance in the process of reclaiming mire and the mire protection. 展开更多
关键词 MIRE DISTRIBUTION UTILIZATION and PROTECTION of MIRE MIRE TYPES NORTHEAST of China
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THE ECOLOGICAL FEATURES AND ECOLOGICAL CONSTRUCTIONS OF A MIRE IN CHINA
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作者 黄锡畴 《Chinese Geographical Science》 SCIE CSCD 1991年第1期56-63,共8页
A mire as an ecosystem, usually is considered as an aquatic ecosystem,or a terrestrial ecosystem. The author thinks that mire is a special ecosystem between these two ecosystems, and proposes the new concept that a mi... A mire as an ecosystem, usually is considered as an aquatic ecosystem,or a terrestrial ecosystem. The author thinks that mire is a special ecosystem between these two ecosystems, and proposes the new concept that a mire is a natural ecosystem with transitional nature of semi-water and semi-land formed by water and land interaction. The paper discusses the nature of the mire ecosystem, the exploitation and utilization and ecological construction of a mire. 展开更多
关键词 MIRE ECOSYSTEM nature of semi-water and semi- land ECOLOGICAL CONSTRUCTIONS
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ESTIMATION OF VEGETATIVE SURFACE ALBEDO IN THE KUSHIRO MIRE WITH LANDSAT TM DATA──A New Approach to Atmospheric and Spectral Corrections
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作者 赵文经 赵焕宸 《Chinese Geographical Science》 SCIE CSCD 1997年第3期278-288,共11页
A method has been developed for estimating the filtered narrow band surface albedo with Landsat/TM date. In this method, the surface albedo from fitered range of Landsat/TM is converted to the surface albedo with unfi... A method has been developed for estimating the filtered narrow band surface albedo with Landsat/TM date. In this method, the surface albedo from fitered range of Landsat/TM is converted to the surface albedo with unfiltered spcectral range. The atmospheric effects on each channel are systematically different, because of the different spectral behavior of atmospheric parameters.As a result, in this study, atmospheric correction has ho done respectively in different parameters for visible and infrared channels. The surface albedos of the Kushiro Mire gotten with this method were compared with the observed date there. The results show that the satellite inferred albedos have a good agreement tO the diurnal mean of ground observed albedos with 3% systematic error. There is a seasonal variation of albedo in high and low mires, the albedo decreased gradually from April to July and reached its minimum in July, further it rose gradually from August to October. It is also clear that there is a characteristic pattern of surface distribution according to the vegetation types of this area. The average surface albedos of each type of community are 0.164 for Sphagnum, 0.175 for Carex, 0.179 for Pragmites and 0.166 for Alnus. In the other words, the albedo in high mire (mainly covered by Sphagnum) is lower than that in low mire (mainly covered by phragmites and Carex). 展开更多
关键词 MIRE VEGETATION surface ALBEDO LANDSAT images remote sensing
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THE MAIN METEOROLOGICAL FACTORS OF FORMATION AND DEVELOPMENT OF MIRE MEADOW OF QINGHAI LAKE DRAINAGE AREA
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作者 周筠君 周立华 《Chinese Geographical Science》 SCIE CSCD 1998年第3期41-47,共0页
I.INTRODUCTIONInthepaper,thewetlandinQinghaiLakedrainageareameansthemiremeadowintheregion.Itsformationanddev... I.INTRODUCTIONInthepaper,thewetlandinQinghaiLakedrainageareameansthemiremeadowintheregion.Itsformationanddevelopmentareclosel... 展开更多
关键词 QINGHAI LAKE drainage area FORMATION and development of MIRE METEOROLOGICAL FACTORS
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FLOROGEOGRAPHY OF MIRE PLANTS IN SOUTHERN PART OF QINGHAI-XIZANG PLATEAU AND ITS ADJACENT AREAS
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作者 赵魁义 《Chinese Geographical Science》 SCIE CSCD 1998年第1期45-53,共0页
FLOROGEOGRAPHYOFMIREPLANTSINSOUTHERNPARTOFQINGHAIXIZANGPLATEAUANDITSADJACENTAREASZhaoKuiyi(赵魁义)ChangchunIns... FLOROGEOGRAPHYOFMIREPLANTSINSOUTHERNPARTOFQINGHAIXIZANGPLATEAUANDITSADJACENTAREASZhaoKuiyi(赵魁义)ChangchunInstituteofGeography... 展开更多
关键词 florogeography MIRE plant the QINGHAI Xizang PLATEAU
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ON THE INFORMATION OF MIRE DEPOSITIONAL ENVIRONMENT
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作者 马学慧 王荣芬 《Chinese Geographical Science》 SCIE CSCD 1992年第2期70-78,共9页
Mire is the product of the Quaternary. It mostly formed, developed and declined after the postglacial age. Therefore the chemical element analysis, spore-pollen analysis, 14C dating, mire plant determination for mire ... Mire is the product of the Quaternary. It mostly formed, developed and declined after the postglacial age. Therefore the chemical element analysis, spore-pollen analysis, 14C dating, mire plant determination for mire sediment, and the study on hierarchy relation of mire sediment, can provide a lot of information for restoring paleogeography, paleoclimate and environmental change. So some people called mire sediment-peat as 'database of environment'. 展开更多
关键词 MIRE SEDIMENT chemical elements ANALYSIS spore-pollen ANALYSIS 14C DATING ENVIRONMENTAL information
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单频红外线光能照射仪治疗DPN疗效观察 被引量:6
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作者 刘玉萍 黄淑玉 《实用糖尿病杂志》 2009年第5期52-52,55,共2页
将70例并发DPN的糖尿病患者随机分为观察组40例采用MIRE治疗,对照组30例采用早钻胺片口服治疗,2周后比较治疗效果。结果1、观察组较对照组MNSI症状评分明显降低(P<0.05);2、10g尼龙丝、数字震动感觉阈值检查示观察组较对照绒组感觉... 将70例并发DPN的糖尿病患者随机分为观察组40例采用MIRE治疗,对照组30例采用早钻胺片口服治疗,2周后比较治疗效果。结果1、观察组较对照组MNSI症状评分明显降低(P<0.05);2、10g尼龙丝、数字震动感觉阈值检查示观察组较对照绒组感觉恢复更理想(P<0.05);3、观察组踝肱比值(ABI)及捕动指数(PI)值上升,阴力指数(RI)下降未血游戏改善明显,而对照组无明显改变(P<0.05)。结论单MIRE不仅可明显改善糖尿病患者周围神经病变症状,还明显改善患者感觉及血流量化指标,是一种治疗DPN的非常有效的方法。 展开更多
关键词 单频红外线光能照射仪(MIRE) 神经病变诊断箱 糖尿病周围神经病变(DPN)
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Molecular cloning and comparative analysis of transcripts encoding chemosensory proteins from two plant bugs, Lygus lineolaris and Lygus hesperus 被引量:1
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作者 J.Joe Hull Omaththage P.Perera Mei-Xian Wang 《Insect Science》 SCIE CAS CSCD 2020年第3期404-424,共21页
Chemosensory proteins(CSPs)are soluble carrier proteins typically characterized by a six‐helix bundle structure joined by two disulfide bridges and a conserved Cys spacing pattern(C1‐X6‐8‐C2‐X16‐21‐C3‐X2‐C4).... Chemosensory proteins(CSPs)are soluble carrier proteins typically characterized by a six‐helix bundle structure joined by two disulfide bridges and a conserved Cys spacing pattern(C1‐X6‐8‐C2‐X16‐21‐C3‐X2‐C4).CSPs are functionally diverse with reported roles in chemosensation,immunity,development,and resistance.To expand our molecular understanding of CSP function in plant bugs,we used recently developed transcriptomic resources for Lygus lineolaris and Lygus hesperus to identify 17 and 14 CSP‐like sequences,respectively.The Lygus CSPs are orthologous and share significant sequence identity with previously annotated CSPs.Three of the CSPs are predicted to deviate from the typical CSP structure with either five or seven helical segments rather than six.The seven helix CSP is further differentiated by an atypical C3‐X3‐C4 Cys spacing motif.Reverse transcriptase PCR‐based profiling of CSP transcript abundance in adult L.lineolaris tissues revealed broad expression for most of the CSPs with antenna specific expression limited to a subset of the CSPs.Comparative sequence analyses and homology modeling suggest that variations in the amino acids that comprise the Lygus CSP binding pockets affect the size and nature of the ligands accommodated. 展开更多
关键词 CHEMOSENSATION chemosensory protein homology modeling Lygus plant bug mired TRANSCRIPTOME
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Ant colonization increased total mercury but reduced methylmercury contents in boreal mires, Northeast China
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作者 Zhongsheng Zhang Xuehui Zhang +1 位作者 Yuan Xin Haitao Wu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第9期50-58,共9页
Soil macroinvertebrates as ecosystem engineers play significant, but largely ignored, roles in affecting mercury(Hg) cycle by altering soil physical-chemical properties. Ant is likely expanded into boreal mires with c... Soil macroinvertebrates as ecosystem engineers play significant, but largely ignored, roles in affecting mercury(Hg) cycle by altering soil physical-chemical properties. Ant is likely expanded into boreal mires with climate warming, however, its impacts on Hg cycle remained poorly understood. We compared total Hg(THg) and methylmercury(Me Hg) contents in soils from antmounds( Lasius flavus) and the nearby ambient in a boreal mire in Northeast China. The present work seeks to unravel factors that controlling Me Hg levels in case of ant appearance or absence. The average THg was 179 μg/kg in the ant mound and was 106.1 μg/kg in nearby soils, respectively. The average Me Hg was 10.9 μg/kg in the ant mound and was 12.9 μg/kg in nearby soils, respectively. The ratios of Me Hg to THg(%Me Hg) were 7.61% in ant mounds and 16.75% in nearby soils, respectively. Ant colonization caused THg enrichment and Me Hg depletion, and this change was obvious in the 10-20 cm depth soil layer where ants mainly inhabited. Spectrometry characteristics of soil dissolved organic matter(DOM) exert a stronger control than microorganisms on Me Hg variation in soils. A structural equation model revealed that the molecular weight of DOM inhibited Me Hg irrespective of ant presence or absence, while humification conducive to Me Hg significantly in ant mound soils. Microorganisms mainly affected Hg methylation by altering the molecular weight and humification of DOM. We propose that the effects of ant colonization on Me Hg rested on DOM feature variations caused by microorganisms in boreal mires. 展开更多
关键词 Ant colonization Mercury METHYLMERCURY Boreal mire DOM spectrometry
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Traditional grazing management creates heterogeneous swards and fosters grasshopper densities
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作者 Cinja Schwarz Thomas Fartmann 《Insect Science》 SCIE CAS CSCD 2022年第6期1805-1818,共14页
Common pastures were once the dominant type of land use in many Euro-pean regions.However,during the past 150 years,they have declined dramatically.Recent studies have shown that they are hotspots for rare plant,butte... Common pastures were once the dominant type of land use in many Euro-pean regions.However,during the past 150 years,they have declined dramatically.Recent studies have shown that they are hotspots for rare plant,butterfly,and bird species in the study area,the Bavarian pre-Alps(southern Germany).However,studies on the value of these pastures for Orthoptera(hereinafter termed"grasshoppers")have been scarce.Here,we studied the effects of traditional summer grazing in common pastures on grasshopper assemblages.Our study revealed that grasshopper species richness did not differ between common pastures(n=57)and controls(n=57).By contrast,density of all and of threat-ened species varied between common pastures and controls in all plots and within the two vegetation types with the highest grasshopper abundance,grasslands on mineral soil and fens.Two threatened species,Pseudochorthippus montanus and Stethophyma grossum,were identified as indicators for common pastures;controls had no indicative species.Traditional low-intensity grazing in common pastures has resulted in open and heteroge-neous swards with some bare ground,a low cover of litter and an intermediate vegetation height favouring high densities of grasshopper species in general and threatened species in particular.This is especially true for the two most productive vegetation types,grasslands on mineral soil and fens.To promote biodiversity in general and grasshopper densities in particular,we recommend maintaining traditional cattle grazing(stocking capacities:0.5-2.0 livestock units/ha)in common pastures.Where possible,this grazing regime should also be introduced in the surrounding landscape. 展开更多
关键词 biodiversity conservation common pasture habitat heterogeneity insect abundance land-usechange mire ecosystem
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