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American Journal of Plant Sciences 2018年第4期9卷 845-864页

作者： xingxi gao Steven Locke Junzeng Zhang Jyoti Joshi Gefu Wang-Pruski Department of Plant Food and Environmental Sciences Faculty of Agriculture Dalhousie University Truro Canada Department of Edible Fungi Science Faculty of Agriculture Ludong University Yantai China Aquatic and Crop Resource Development Research Centre National Research Council of Canada Charlottetown Canada Aquatic and Crop Resource Development Research Centre National Research Council of Canada Halifax Canada

Phosphite (Phi)-based fungicides are used to control the oomycete Phytophthora infestans which causes late blight disease, the most devastating disease in potatoes. In order to examine the effects of Phi-based fungicides on potato tubers through foliar or post-harvest application, a metabolite profiling approach based on gas chromatography coupled to mass spectrometry (GC-MS) has been established. A total of 132 metabolites were detected using the GC-MS approach. Among these, 34 metabolites were identified after normalization and annotated with a compound name with standard mass spectral library. Metabolomic analysis of Phi-treated plants showed significant differences in the levels of many metabolites especially amino acids. Multivariate statistical approaches, such as principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), were employed to explore the relationships between metabolites to detect group differences. A good discrimination between the control and the Phi-treated plants was observed, which demonstrated that significant changes in the metabolite profile have been caused by the two different Phi applications (foliar or post-harvest). This finding suggests that the alteration of specific metabolite levels by accumulation of Phi can lead to resistance against the pathogen.

关键词： Potato Metabolomics GC-MS Phosphite Phytophthora infestans

我国猴头栽培菌株的反转录转座子间扩增多态性

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东北林业大学学报 2012年第7期40卷 68-70页

作者：王俊图力古尔高兴喜吉林农业大学长春130118 鲁东大学

IRAP作为一种新的DNA分子标记技术,具有简便、稳定、中等产率和容易得到选择性条带序列的特点。利用基于反转录转座子的分子标记技术,即反转录转座子间扩增多态性(IRAP)技术分析我国34份栽培猴头菌菌株种间遗传差异,为猴头菌道地性研究... 详细信息

IRAP作为一种新的DNA分子标记技术,具有简便、稳定、中等产率和容易得到选择性条带序列的特点。利用基于反转录转座子的分子标记技术,即反转录转座子间扩增多态性(IRAP)技术分析我国34份栽培猴头菌菌株种间遗传差异,为猴头菌道地性研究、种质资源鉴定、亲缘关系研究、品种选育和引种栽培提供了分子生物学依据。结果表明,34个猴头菌菌株间均有遗传上的差异,但遗传相关性极高,同时表明我国猴头菌栽培菌株间的遗传背景较单一。

关键词：猴头茵栽培菌株反转录转座子间扩增多态性

外生菌根在森林生态系统中的重要性(Ⅰ)──外生菌根对宿主树木的影响

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东北林业大学学报 1999年第6期27卷 72-77页

作者：杨国亭宋关玲高兴喜东北林业大学哈尔滨150040

文章根据国内外的菌根文献资料，综述了外生菌根形成对宿主树木的影响。外生菌根对宿主树木的主要作用包括：外生菌粮能扩大树木根系的吸收面积和吸收范围、增强宿主树木对营养元素的吸收和利用．菌根菌还能通过合成植物激素来调节共生... 详细信息

文章根据国内外的菌根文献资料，综述了外生菌根形成对宿主树木的影响。外生菌根对宿主树木的主要作用包括：外生菌粮能扩大树木根系的吸收面积和吸收范围、增强宿主树木对营养元素的吸收和利用．菌根菌还能通过合成植物激素来调节共生双方。菌根还能提高宿主树木的抗病性和抗逆性。

关键词：外生菌根宿主树木森林生态系统

黑龙江省东部山区谷地云冷杉林衰退与病虫害的相关性

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东北林业大学学报 2007年第7期35卷 4-6页

作者：邢亚娟王庆贵高兴喜黑龙江省林业科学研究所哈尔滨150040 黑龙江大学哈尔滨工业大学

对黑龙江省伊春林区丰林国家级自然保护区和凉水国家级自然保护区谷地云冷杉林内的线虫、云杉树体各个部位的受害症状、病原菌及菌根真菌进行了调查,并分析了黑龙江省东部山区谷地云冷杉林衰退的原因。结果表明:线虫的数量和种类与云杉... 详细信息

对黑龙江省伊春林区丰林国家级自然保护区和凉水国家级自然保护区谷地云冷杉林内的线虫、云杉树体各个部位的受害症状、病原菌及菌根真菌进行了调查,并分析了黑龙江省东部山区谷地云冷杉林衰退的原因。结果表明:线虫的数量和种类与云杉死亡无明显关系;云杉林内的虫害是次期性的,不是直接的致死因子;云杉本身的病害不是导致云杉林衰退的直接原因;云杉菌根呈现出的衰退局势可能是导致云杉林衰退的一个因素。

关键词：黑龙江省东部山区谷地云冷杉林衰退病虫害相关性

Record-high efficiency perovskite LEDs achieved by accelerating radiative recombination

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Science China Materials 2024年第9期67卷 3039-3040页

作者： Feng gao Department of Physics Chemistry and BiologyLinköping UniversityLinköping58183Sweden

Light-emitting diodes(LEDs)have revolutionized the lighting and displays due to their superior energy *** increasing demand for more efficient and brighter thin-film LEDs in flat-panel displays and solid-state lighting applications has driven extensive research into perovskite materials,which show great promise for high brightness and efficiency.

关键词： lighting radiative high

Stress tensor determination by modified hydraulic tests on pre-existing fractures:Method and stress constraints

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1637-1648页

作者： Guiyun gao Chenghu Wang Ke gao National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing100085China Beijing Engineering Research Center of Earthquake Observation Beijing100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing100085China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen518055China

The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor ***,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable *** this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests *** shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo ***,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress *** inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress *** stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)*** results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress *** inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints *** M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole.

关键词： Stress tensor Hydraulic tests on pre-existing fractures Mean stress Stress constraint Hydraulic fracturing

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun gao Yan Peng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting *** effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in *** each rotation,the casting wheel passes through four different spray *** results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,*** temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones

Numerical simulation of fluid flow and free surface fluctuations during wheel and belt casting process

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Journal of Iron and Steel Research International 2024年第5期31卷 1117-1126页

作者： Kun gao Yan Peng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina

The unstable fluid flow and severe free surface fluctuations in the wheel and belt caster can affect the quality of the cast *** lower level height tends to entrap inclusions in the molten *** the other hand,the higher level height makes the production process more dangerous due to the overflow of high temperature fluid from the mold.A computational model of the molten metal pouring process was *** transient fluid flow and free surface fluctuations behavior were calculated using the three-dimensional large eddy simulation model and the volume of fluid *** results show that the flow velocity of the main jet gradually decreases under the influence of the low kinetic energy fluid in the *** is an obvious oscillation in the tail of the jet,while the flow field is asymmetric in *** jet is closer to the inside radius side due to the Coanda effect,and there is a recirculation zone on the inside radius and the outside radius respectively,according to the 10 s time-averaged *** with the industrial observation and simulation results,the shape of the free surface is a wave that varies with *** addition,the free surface height is lowest and the flow velocity is highest in the region near the jet.

关键词： Fluid flow Free surface Wheel and belt caster Large eddy simulation Volume of fluid method

On the core entropy of Newton maps

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Science China Mathematics 2024年第1期67卷 77-128页

作者： Yan gao Department of Mathematics Shenzhen UniversityShenzhen 518060China

In this paper,we define the core entropy for postcritically-finite Newton maps and study its continuity within this *** show that the entropy function is not continuous in this family,which is different from the polyn... 详细信息

关键词： core entropy extended Newton graph critical marking polynomial Newton map