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川西北哲波山金矿床地球化学特征及找矿标志
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作者 陈康林 郑明华 吕新彪 《成都理工学院学报》 CAS CSCD 北大核心 2002年第3期246-251,共6页
对哲波山微细浸染型金矿床地球化学特征进行初步的研究得出 :矿床次生晕中 Au,As关系密切 ,As是最佳指示元素 ;矿床原生晕特征在不同的成矿阶段表现出不同的特征。在热液成矿作用的早期石英 -毒砂 -黄铁矿阶段以富集 Au,Ag,As,Sb,Bi,W,M... 对哲波山微细浸染型金矿床地球化学特征进行初步的研究得出 :矿床次生晕中 Au,As关系密切 ,As是最佳指示元素 ;矿床原生晕特征在不同的成矿阶段表现出不同的特征。在热液成矿作用的早期石英 -毒砂 -黄铁矿阶段以富集 Au,Ag,As,Sb,Bi,W,Mo组合为特征 ,与岩浆演化关系密切 ,地表与之对应的氧化矿为“红矿”。成矿作用的晚期则富集 Au,Ag,As,Sb,Bi,B组合为特征 ,与其有关的热液流体为地下水热液 ,地表与之对应的氧化矿为“灰矿”。总体上分析 As,Bi,B,Ag为哲波山金矿床的特征指示元素 ,对“红矿”可增加 Co,Pb作为辅助指示元素 ; 展开更多
关键词 次生晕 原生晕 地球化学特征 波山金矿床
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应用基因编辑技术对缅甸优质稻品种波山的遗传改良
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作者 Ei Ei Khine Khin Mar Thi +2 位作者 Ei Ei Nyein 吴为人 郑燕 《分子植物育种》 CAS 北大核心 2022年第8期2607-2616,共10页
波山水稻是缅甸特有的一类优质稻品种,因其米饭口感好、气味香,深受缅甸人民喜爱,在东南亚享有盛名。然而,波山水稻具有植株高、生育期长、产量低的缺点,极大限制了其在缅甸的广泛种植和出口。为解决这个问题,必须对波山水稻的株高和生... 波山水稻是缅甸特有的一类优质稻品种,因其米饭口感好、气味香,深受缅甸人民喜爱,在东南亚享有盛名。然而,波山水稻具有植株高、生育期长、产量低的缺点,极大限制了其在缅甸的广泛种植和出口。为解决这个问题,必须对波山水稻的株高和生育期性状进行遗传改良。本研究对来自缅甸的22份波山水稻品种进行遗传亲缘关系分析和表型鉴定,并以其中的一个典型的波山品种‘PSH-21’为材料,利用CRISP/Cas9基因编辑技术,对‘PSH-21’中的半矮秆基因Sd1和光周期敏感基因Ghd7进行基因敲除。结果表明敲除这两个基因之后,‘PSH-21’的株高降低了55 cm,生育期也明显缩短,而对其他农艺性状影响不大。本研究结果为缅甸波山水稻的遗传改良提供了良好的材料基础。 展开更多
关键词 水稻 波山 生育期 遗传改良 基因编辑
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北京地区山背波监测与特征分析 被引量:1
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作者 郭泉 吕君 《声学技术》 CSCD 北大核心 2015年第3期247-251,共5页
利用北京西北地区布置的小孔径大气次声传感器网络,利用有效来波判断方法搜寻有效来波,并使用最小方差空间搜索方法定位波源,分析经常发生并对正常观测造成干扰的一种次声波—山背波信号的特征规律:幅度、频谱、波源位置、波速、来波... 利用北京西北地区布置的小孔径大气次声传感器网络,利用有效来波判断方法搜寻有效来波,并使用最小方差空间搜索方法定位波源,分析经常发生并对正常观测造成干扰的一种次声波—山背波信号的特征规律:幅度、频谱、波源位置、波速、来波方向及发生时间统计规律。对2013年4~5月的次声波记录数据进行分析,结果显示:低于0.02 Hz频段,各传感器经常性接收到来自于西北山区方位的次声波,幅度一般在10~20 Pa,中心频率处于0.002~0.005 Hz,最小方差法定位结果显示信号源大多自北京西山的面向阵列的一侧,方位角统计结果显示大多数在260°~360°、0°~40°,且传播速度为10~50 m/s,该波的发生与当地的风速风向具有相关性。 展开更多
关键词 小孔径阵列 定位 统计特征
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山背波:对飞机的潜在威胁 被引量:1
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作者 杨训仁 《应用声学》 CSCD 1995年第4期28-33,共6页
山背波河飞机的潜在威胁现已毋庸置疑.为了提高在这方面作出更确切判断的能力并能进一步找出实践中可行的相应措施,首要的问题就是必须对山背波本身有足够的认识,而这正是当前国内文献中极为薄弱的环节.有鉴于此,本文系统地、较全... 山背波河飞机的潜在威胁现已毋庸置疑.为了提高在这方面作出更确切判断的能力并能进一步找出实践中可行的相应措施,首要的问题就是必须对山背波本身有足够的认识,而这正是当前国内文献中极为薄弱的环节.有鉴于此,本文系统地、较全面地介绍了山背波这种独特的次声波,对其发生机理和基本特征、以及作为其直接衍生物的相关云相和晴空湍流──—后者正是对飞机的主要潜在威胁所在──—作出简明扼要的评述. 展开更多
关键词 潜在威胁 晴空湍流 飞机 次声
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美国华盛顿州太波山星友会
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作者 戴明 《天文爱好者》 2005年第4期10-11,共2页
由于本刊将在今年8月份举行《天文爱好者》星空大会,为了使读者能够了解到天文聚会的活动形式、增加读者参与的兴趣,本刊将陆续介绍一些国外的大型天文聚会,以便读者对大会有一个直观的印象.
关键词 天文聚会 活动形式 波山星友会 天文事业
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林海扬波山叠翠
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作者 爱因思美 《研究与交流》 2004年第3期37-37,共1页
在平原长大的人,骤然来到地处北回归线满眼浓翠的森林,你会惊讶得目瞪口呆。人被茂密的树林包围了,看不到全景,看不到远处,看不清出路,即使你心里有一张风帆,也无法像在海里自在地遨游,只能在神秘的树林中寻找出路,探索前进。... 在平原长大的人,骤然来到地处北回归线满眼浓翠的森林,你会惊讶得目瞪口呆。人被茂密的树林包围了,看不到全景,看不到远处,看不清出路,即使你心里有一张风帆,也无法像在海里自在地遨游,只能在神秘的树林中寻找出路,探索前进。这林子真是一个欣赏自然妙趣的好地方啊! 展开更多
关键词 《林海扬波山叠翠》 中国 爱因思美 散文
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云南峨山波司甸铜矿床成矿规律及找矿潜力 被引量:1
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作者 张兴林 《云南地质》 2013年第4期412-416,共5页
波司甸铜矿床是云南易门铜矿区南段赋存于中元古界昆阳群落雪组中的典型喷流—热卤水沉积型铜矿床。矿床地质特征、成矿控制因素的研究,对云南易门铜矿区南段的找矿工作具有较好的指导意义。
关键词 多种铜矿 喷流热卤水型 不同成矿条件 昆阳群落雪组 云南峨司甸
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Genetic Polymorphism of Ten Microsatellites in Two Goat Breeds and Its Relationship with Heterosis
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作者 李晓锋 马月辉 +4 位作者 熊琪 索效军 张年 杨前平 陈明新 《Agricultural Science & Technology》 CAS 2013年第8期1078-1084,共7页
[Objective] This study aimed to investigate the genetic diversity of Macheng black goat and its correlation with heterosis.[Method] Ten microsatellite markers were selected for polymorphism investigation and statistic... [Objective] This study aimed to investigate the genetic diversity of Macheng black goat and its correlation with heterosis.[Method] Ten microsatellite markers were selected for polymorphism investigation and statistical analysis of Boer goat and Macheng black goat populations.[Result] The results showed that totally 175 alleles were found in 10 microsatellite loci; to be specific,the maximum number of detected alleles was 23,and the minimum number was 10; the effective number of alleles (Ne) was 6.4-18.1,with absolute difference value of 1.6-8.1 from the observed number of alleles.The highest gene frequency was 0.239 1 and the lowest was 0.002 7.The polymorphic information contents of all the ten microsatellite markers were above 0.95.The observed heterozygosity (Ho) ranged from 0.616 7 to 0.984 4 and the expected heterozygosity (He) ranged from 0.844 1 to 0.944 6.The average expected heterozygosity of Boer goat and Macheng black goat was respectively 0.894 0 and 0.906 7.Various body weight and body size indices of Boer goatxMacheng black goat hybrids were improved in varying degrees compared with Macheng black goat (with an increase range of 0.32%-30.06%).The average heterosis rates of body height and chest girth were relatively high,while average heterosis rate of body weight was relatively low.[Conclusion] The genetic distance between Boer goat and Macheng black goat was 0.379 5,which is consistent with the geographical distribution of Boer goat and Macheng black goat populations and is fully relevant to the heterosis of Boer goat × Macheng black goat hybrids,indicating that investigating polymorphism via microsatellite loci is one of the feasible means to predict and analyze heterosis between varieties. 展开更多
关键词 Microsatellite marker Genetic polymorphism Boer goat Macheng blackgoat HETEROSIS
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新邮报道
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《上海集邮》 2007年第12期6-6,共1页
喜临门;2007-25T贡嘎山与波波山;木艺精华;科学与科技—黄金比例;
关键词 贡嘎 邮票 喜临门 波山 木艺精华 科学与科技—黄金比例 集邮
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新疆百里风区强风中尺度特征分析 被引量:4
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作者 汤浩 周雅蔓 +1 位作者 杨杰尧 潘新民 《沙漠与绿洲气象》 2022年第4期1-8,共8页
大尺度环流背景和天山山脉大地形共同作用形成新疆百里风区,其风力居全疆九大风区之首。为进一步研究百里风区强风中尺度特征及其与局地地形的关系,选取2018年5月6—8日百里风区强风天气过程,使用WRF模式进行中尺度模拟分析,得出以下结... 大尺度环流背景和天山山脉大地形共同作用形成新疆百里风区,其风力居全疆九大风区之首。为进一步研究百里风区强风中尺度特征及其与局地地形的关系,选取2018年5月6—8日百里风区强风天气过程,使用WRF模式进行中尺度模拟分析,得出以下结论:天山两侧气压梯度力驱动下冷空气翻越天山,经色皮山口狭管效应和过山波水跃下沉接力加速,在背风坡上空形成强风区,强风区接地形成百里风区地面大风;大风过程中,七角井盆地地形强迫引发有限振幅重力波,背风坡上空大风区之上的临界层吸收上层能量并向下传递,增大了大风区的风速,使低空大风区的接地更加充分。低空大气稳定层结的强度与大风强度相对应。 展开更多
关键词 百里风区 狭管效应 水跃下沉 稳定层结
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Microwave Technique for Polysaccharide Extraction from Dendrobium huoshanense 被引量:6
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作者 先桂花 李滨 臧恒昌 《Agricultural Science & Technology》 CAS 2014年第8期1304-1307,1367,共5页
The effect of material granularity, extraction times, extraction time, mi-crowave power and solid-liquid ratio on the yield of polysaccharide of Dendrobium huoshanense in microwave-assisted extraction was discussed th... The effect of material granularity, extraction times, extraction time, mi-crowave power and solid-liquid ratio on the yield of polysaccharide of Dendrobium huoshanense in microwave-assisted extraction was discussed through single factor experiment. The key factors in polysaccharide extraction and the advantages over the traditional extraction method were studied based on orthogonal experiment. The results showed that the influences became unobvious with the promotion of the fac-tor’s level. The orthogonal experiment showed that the optimal factor in the mi-crowave-assisted extraction was that the sample was extracted for four times with an extraction time of 40 min under 550 W. Al these results would lay a founda-tion for exploring a new method for the extraction of polysaccharide from Dendrobi-um huoshanense. 展开更多
关键词 Dendrobium huoshanense POLYSACCHARIDE Microwave technique Orthogonal analysis
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Phytoplankton community structure in reservoirs of different trophic status, Northeast China 被引量:10
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作者 马成学 于洪贤 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第3期471-481,共11页
The aim of this study was to determine the phytoplankton community structures of reservoirs of different trophic status, located in a cold region. Physical and chemical variables and the phytoplankton communities were... The aim of this study was to determine the phytoplankton community structures of reservoirs of different trophic status, located in a cold region. Physical and chemical variables and the phytoplankton communities were investigated in two reservoirs (Xiquanyan Reservoir and Taoshan Reservoir) in Northeast China in 2009. The two reservoirs showed strong seasonal fluctuations in their physical and chemical composition. Results of the trophic status index indicated that Xiaquanyan Reservoir was mesotrophic, whilst Taoshan Reservoir was eutrophic. Diatoms were the dominant phytoplankton group in Xiquanyan Reservoir throughout all seasons of the study, while in Taoshan Reservoir, diatoms dominated in spring, and cyanobacteria dominated in summer and autumn. This difference was resulted from differences in local environmental factors, including nutrients and hydrology. This study suggests that in mesotrophic reservoirs, nutrients played a key role in controlling seasonal phytoplankton successions, whereas in eutrophic reservoirs water temperature was the key factor in a cold region. Notably, the dominant species in summer in the Taoshan Reservoir was Microcystis, which may produce toxins depending on the ambient conditions, and presenting a risk of local toxin contamination. 展开更多
关键词 trophic status phytoplankton community RESERVOIR cold region
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Determination of Trace Elements in Famous Teas from Huangshan Area by ICP-AES
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作者 赵宗明 《Agricultural Science & Technology》 CAS 2016年第5期1046-1047,1054,共3页
With an Iris Intrepid II XSP ICP full spectrum ICP emission spectrometer,trace elements including Se,Fe,Mn,Cd,Cr,Co,Ni,Cu,Pb and Zn in Huangshan teas were determined.The best analysis conditions were selected by exper... With an Iris Intrepid II XSP ICP full spectrum ICP emission spectrometer,trace elements including Se,Fe,Mn,Cd,Cr,Co,Ni,Cu,Pb and Zn in Huangshan teas were determined.The best analysis conditions were selected by experiments.The method is simple and rapid,and the precision and accuracy are all in line with the requirements.This method was used to analyze actual tea samples with satisfactory results. 展开更多
关键词 Microwave digestion ICP-AES Famous teas in Huangshan area Trace elements
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Effective wave identification and interference analysis of the seismic reflection method in mines 被引量:1
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作者 HU Yun-bing WU Yan-qing KANG Hou-qing 《Journal of Coal Science & Engineering(China)》 2009年第3期308-312,共5页
Through discussion of the time-distance curve characteristics of the direct waveand from the front,side and rear of the reflection waves of the seismic reflection methodfor advanced exploration in mines,and analysis o... Through discussion of the time-distance curve characteristics of the direct waveand from the front,side and rear of the reflection waves of the seismic reflection methodfor advanced exploration in mines,and analysis of several major interference waves inmines,the differences in time-distance curve,frequency,apparent velocity between theeffective wave and interference wave in the seismic reflection method for advanced explorationare obtained.According to the differences,the effective wave is extracted andthe interference wave is filtered and the system's precision and accuracy is improved. 展开更多
关键词 INTERFERENCE seismic reflection method MINE effective wave
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Recognition of Milankovitch cycles in the stratigraphic record: application of the CWT and the FFT to well-log data 被引量:8
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作者 YU Ji-feng SUI Feng-gui +2 位作者 LI Zeng-xue LIU Hua WANG Yu-lin 《Journal of China University of Mining and Technology》 EI 2008年第4期594-598,共5页
The authors applied a the combination of Continuous Wavelet Transform (CWT) and Fast Fourier Transform (FFT) methods to gamma ray well-log data from the Q3, G1 and D2 wells. This high-resolution stratigraphic study wa... The authors applied a the combination of Continuous Wavelet Transform (CWT) and Fast Fourier Transform (FFT) methods to gamma ray well-log data from the Q3, G1 and D2 wells. This high-resolution stratigraphic study was based on Milankovitch's orbital cycle theory. It was found that the CWT scale factors, ‘a,’ of 12, 24 and 60 match the ratios of the periodicities of precession, obliquity and eccentricity very well. Nine intervals of the Permo-carboniferous strata were recognized to have Milankovitch cycles in them. For example, section A of well Q3 has 29 precession cycles, 15 obliquity cycles and 7 short eccentricity cycles. The wavelengths are 2.7, 4.4 and 7.8 m for precession, obliquity and eccentricity, respectively. Important geological parameters such as the stratigraphic completeness and the accumulation rate were also estimated. These results provide basic information for further cyclostratigraphic correlation studies in the area. They are of great significance for the study of ancient and future climate change. 展开更多
关键词 Milankovitch cycle continuous wavelet transform (CWT) fast Fourier transform (FFT) well logs
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Tree wave migration across an elevation gradient in the Altai Mountains,Siberia 被引量:1
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作者 Viacheslav I.KHARUK Sergei T.IM +2 位作者 Maria L.DVINSKAYA Kenneth J.RANSON Il'ya A.PETROV 《Journal of Mountain Science》 SCIE CSCD 2017年第3期442-452,共11页
The phenomenon of tree waves (hedges and ribbons) formation within the alpine ecotone in Altai Mountains and its response to observed air temperature increase was considered. At the upper limit of tree growth Siberi... The phenomenon of tree waves (hedges and ribbons) formation within the alpine ecotone in Altai Mountains and its response to observed air temperature increase was considered. At the upper limit of tree growth Siberian pine (Pinus sibirica) forms hedges on windward slopes and ribbons on the leeward ones. Hedges were formed by prevailing winds and oriented along winds direction. Ribbons were formed by snow blowing and accumulating on the leeward slope and perpendicular to the prevailing winds, as well as to the elevation gradient. Hedges were always linked with microtopography features, whereas ribbons were not. Trees are migrating upward by waves and new ribbons and hedges are forming at or near tree line, whereas at lower elevations ribbons and hedges are being transformed into dosed forests. Time series of high-resolution satellite scenes (from 1968 to 2OLO) indicated an upslope shift in the position ribbons averaged 155+26 m (or 3-7 m yr^-1) and crown closure increased (about 35%-90%). The hedges advance was limited by poor regeneration establishment and was negligible. Regeneration within the ribbon zone was approximately 2.5 times (5060 vs 2120 ha^-1) higher then within the hedges zone. During the last four decades, Siberian pine in both hedges and ribbons strongly increased its growth increment, and recent tree growth rate for 50 year-old trees was about twice higher than those recorded for similarly-aged trees at the beginning of the 20^th century. Hedges and ribbons are phenomena that are widespread within the southern and northern Siberian Mountains. 展开更多
关键词 Ribbon forest HEDGES Siberian forests Alpine treeline Tree waves Siberian pine AltaiMountains
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Observations and Modeling of Incoming Longwave Radiation to Snow Beneath Forest Canopies in the West Tianshan Mountains, China 被引量:3
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作者 LU Heng WEI Wen-shou +2 位作者 LIU Ming-zhe HAN Xi HONG Wen 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1138-1153,共16页
Forest canopy reduces shortwave radiation and increases the incoming longwave radiation to snowpacks beneath forest canopies. Furthermore, the effect of forest canopy may be changed by complex topography. In this pape... Forest canopy reduces shortwave radiation and increases the incoming longwave radiation to snowpacks beneath forest canopies. Furthermore, the effect of forest canopy may be changed by complex topography. In this paper, we measured and simulated the incoming longwave radiation to snow beneath forest at different canopy openness in the west Tianshan Mountains, China(43°16'N, 84°24'E) during spring 2013. A sensitivity study was conducted to explore the way that terrain influenced the incoming longwave radiation to snow beneath forest canopies. In the simulation model, measurement datasets, including air temperature, incoming shortwave radiation above canopy, and longwave radiation enhanced by adjacent terrain, were applied to calculate the incoming longwave radiation to snow beneath forest canopy. The simulation results were consistent with the measurements on hourly scale and daily scale. The effect of longwave radiation enhanced by terrain was important than that of shortwave radiation above forest canopy with different openness except the 20% canopy openness. The longwave radiation enhanced due to adjacent terrain increases with the slope increase and temperature rise. When air temperature(or slope) is relatively low, thelongwave radiation enhanced by adjacent terrain is not sensitive to slope(or air temperature), but the sensitivity increases with the decrease of snow cover area on sunny slope. The effect of longwave radiation is especially sensitive when the snow cover on sunny slope melts completely. The effect of incoming shortwave radiation reflected by adjacent terrain on incoming longwave radiation to snow beneath forest canopies is more slight than that of the enhanced longwave radiation. 展开更多
关键词 Incoming longwave radiation Snow beneath forest canopy Simulation model Complex topography Sensitivity study
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Effect of weather conditions on the incidence of Lophodermium yellow needle blight in the dwarf mountain pine in the Karkonosze and Izerskie Mountains (Poland)
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作者 Wojciech PUSZ Ryszard WEBER +1 位作者 Andrzej DANCEWICZ Wlodzimierz KITA 《Journal of Mountain Science》 SCIE CSCD 2016年第4期725-733,共9页
The study aimed to determine, by using a statistical model, the effect of weather conditions on the incidence of Lophodermium yellow needle blight causing by new species for science- Lophodermium corconticum, in the m... The study aimed to determine, by using a statistical model, the effect of weather conditions on the incidence of Lophodermium yellow needle blight causing by new species for science- Lophodermium corconticum, in the mountain dwarf pine growing in the subalpine Karkonosze Mountains and the Izerskie Mountains(Poland). Needles showed symptoms of yellow spots, gradual discolouration and premature fall in July. The assessment of healthiness of infected mountain dwarf pine needles spanned three years(2011- 2013) and was conducted in several test sites in the Karkonosze and Izerskie Mountains. The results were analyzed by taking into account the meteorological conditions. Field observations seem to indicate that the highest infestation of mountain dwarf pine occurs in June and July, while September and October see a significantly lower disease index in the Karkonosze Mountains. The lower indices of the infestation of mountain dwarf pine are characteristic for the vegetation in the Hala Izerska high mountain pasture; whereas the environmental conditions prevailing in the Kocio? Ma?ego Stawu cirque and above the Samotnia hostel are conducive to the development of Lophodermium yellow needle blight. 展开更多
关键词 Mountain dwarf pine Fungal diseases Pathogenic fungi Lophodermium corconticum Statistical model
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Verification of Numerical Modeling in 2-D Wave Propagation in Rock 被引量:6
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作者 LEI Wei-dong HEFNY Ashraf +2 位作者 TENG Jun ZHAO Jian SONG Hong-wei 《Journal of China University of Mining and Technology》 EI 2005年第4期309-313,共5页
Compressional harmonic wave propagation from a cylindrical tunnel or borehole in an intact rock is the basis for investigation of the practical explosion waves in a fractured rock mass. The amplitudes of the radial st... Compressional harmonic wave propagation from a cylindrical tunnel or borehole in an intact rock is the basis for investigation of the practical explosion waves in a fractured rock mass. The amplitudes of the radial stress wave obtained from the universal distinct element code (UDEC) were compared with the analytical solutions for two cases with different conditions. Good agreements between the UDEC results and the analytical solutions have been achieved. It indicates that UDEC can model 2-D dynamic problems at a high degree of accuracy. 展开更多
关键词 harmonic wave analytical solution radial stress wave elastic rock.
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Shear-wave Splitting in the Crust beneath Shandong and Its Adjacent Area
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作者 Miao Qingjie Liu Xiqiang +3 位作者 Shi Yuyan Qu Junhao Zheng Jianchang Tian Fengdong 《Earthquake Research in China》 CSCD 2016年第4期556-565,共10页
Based on the seismic data of near-field source from the Shandong Digital Seismic Network,this study obtained the shear-wave splitting parameters from multiple stations. The results show that dominant directions of pol... Based on the seismic data of near-field source from the Shandong Digital Seismic Network,this study obtained the shear-wave splitting parameters from multiple stations. The results show that dominant directions of polarizations of fast shear-waves reflect the spatial distribution characteristics of tectonic stress in this area,CHD and LIS stations show 2 dominant directions,and reveals that the crustal seismic anisotropy in the Shandong area is constrained by the regional stress background,local failure and structure. 展开更多
关键词 Shandong area Shear-wave splitting POLARIZATION Seismic anisotropy Tectonic stress
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