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Modeling tree root diameter and biomass by ground-penetrating radar

Science China Earth Sciences 2011年第5期54卷 711-719页

作者： CUI XiHong CHEN Jin shen jinsong CAO Xin CHEN XueHong ZHU XiaoLin State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China

Roots play a key role in ecosystem functioning as they transfer water and nutrients from soil to plants. Traditional methods for measuring roots are labor-intensive and destructive in nature, which limits quantitative and repeatable assessments in long- term research. Ground-penetrating radar （GPR） provides a non-destructive method to measure plant roots. Based on the superiority of GPR with 2 GHz frequency, we developed a new, practical method to estimate root biomass. First, average root matter density was measured by collecting a small number of root samples. Second, under controlled, experimental conditions in a sandy area, a root diameter estimation model base on GPR was developed from which root diameter was estimated. Third, root volume was calculated using the estimated root diameter and assuming the shape of roots to be cylindrical. Finally, root biomass was estimated by averaging root matter density and root volume. Results of this study suggest the following：（1） the density of coarse roots with diameters greater than 0.5 cm is relatively uniform; （2） a new wave shape parameter, AT, extracted from profile data of 2 GHz frequency antenna is independent of root depth, thus enabling the construction of a root diameter estimation model with high accuracy; and （3） results of a field experiment demonstrated the GPR-based method to be feasible and effective in estimating biomass of coarse roots. These findings are helpful for improving GPR-based root diameter and biomass estimation models and suggest the potential of GPR data in studying root systems.

关键词： ground-penetrating radar tree root system root biomass root diameter

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2.5-D modeling of cross-hole electromagnetic measurement by nite element method

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Petroleum Science 2008年第2期5卷 126-134页

作者： shen jinsong Sun Wenbo Department of Geophysics School of Resources and Information Technology China University of Petroleum Beijing 102249 China CNPC Key Lab of Geophysical Exploration China University of Petroleum Beijing 102249 China

A finite element method is developed for simulating frequency domain electromagnetic responses due to a dipole source in the 2-D conductive structures. Computing costs are considerably minimized by reducing the full three-dimensional problem to a series of two-dimensional problems. This is accomplished by transforming the problem into y-wave number （Ky） domain using Fourier transform and the y-axis is parallel to the structural strike. In the Ky domain, two coupled partial differential equations for magnetic field Hy and electric field Ey are derived. For a specific value of Ky, the coupled equations are solved by the finite element method with isoparametric elements in the x-z plane. Application of the inverse Fourier transform to the Ky, domain provides the electric and magnetic fields in real space. The equations derived can be applied to general complex two-dimensional structures containing either electric or magnetic dipole source in any direction. In the modeling of the electromagnetic measurement, we adopted a pseudo-delta function to distribute the dipole source current and circumvent the problem of singularity at the source point. Moreover, the suggested method used isoparametric finite elements to accommodate the complex subsurface formation. For the large scale linear system derived from the discretization of the Maxwell＇s equations, several iterative solvers were used and compared to select the optimal one. A quantitative test of accuracy was presented which compared the finite element results with analytic solutions for a dipole source in homogeneous space for different ranges and different wave numbers Ky. to validate the addressed the effects of the distribution range τ of the homogeneous medium. code and check its effectiveness. In addition, we pseudo-delta function on the numerical results in

关键词： 2.5-D electromagnetic modeling frequency domain isoparametric finite element pseudo-delta function

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Anisotropic characteristics of electrical responses of fractured reservoir with multiple sets of fractures

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Petroleum Science 2009年第2期6卷 127-138页

作者： shen jinsong Su Benyu Guo Naichuan Department of Geophysics School of Resource and Information Technology China University of Petroleum Beijing 102249 China Key Laboratory of CNPC Geophysical Exploration China University of Petroleum Beijing 102249 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China

In fractured reservoirs, the fractures not but also form the main flow channels which connect productivity of reservoirs. However, because of the only provide the storage space for hydrocarbons, the pores of the matrix, so fractures dominate the heterogeneity and randomness of the distribution of fractures, exploration and evaluation of fractured reservoirs is still one of the most difficult problems in the oil industry. In recent years, seismic anisotropy has been applied to the assessment of fractured formations, whereas electrical anisotropy which is more intense in fractured formations than seismic anisotropy has not been studied or used so extensively. In this study, fractured reservoir models which considered multiple sets of fractures with smooth and partly closed, rough surfaces were established based on the fractures and pore network, and the vertical and horizontal electrical resistivities were derived as a function of the matrix and fracture porosities according to Ohm＇s law. By using the anisotropic resistivity equations, variations of the electrical anisotropy of three types of fractured models under the conditions of free pressure and confining pressure were analyzed through the variations of the exerted pressure, matrix porosity, fracture aperture and formation water resistivity. The differences of the vertical and horizontal resistivities and the anisotropy between the connected and non-connected fractures were also analyzed. It is known from the simulated results that an increase of the confining pressure causes a decrease of electrical anisotropy because of the elasticity of the closed fractures and the decrease of the fracture aperture. For a fixed fracture porosity, the higher the matrix porosity, the weaker the electrical anisotropy in the rock formation.

关键词： Fractured reservoir partly closed fracture electrical anisotropy fracture roughness

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Geophysical methods for the study of sedimentary cycles

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Petroleum Science 2009年第3期6卷 259-265页

作者： Xu Jingling Liu Luofu Wang Guiwen shen jinsong Zhang Chunhua School of Resources and Information Technology China University of Petroleum Beijing 102249 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Department of Computer Science and Technology China University of Petroleum Beijing 102249 China

We present the wavelet depth-frequency analysis and variable-scale frequency cycle analysis methods to study sedimentary cycles. The spectrum analysis, variable-scale frequency cycle analysis, and wavelet depth-frequency analysis methods are mainly discussed to distinguish sedimentary cycles of different levels. The spectrum analysis method established the relationship between the spectrum characteristics and the thickness and number of sedimentary cycles. Both the variable-scale frequency cycle analysis and the wavelet depth-frequency analysis are based on the wavelet transform. The variable-scale frequency cycle analysis is used to obtain the relationship between the periodic changes of frequency in different scales and sedimentary cycles, and the wavelet depth-frequency analysis is used to obtain the relationship between migration changes of frequency energy clusters and sedimentary cycles. We designed a soft-ware system to process actual logging data from the Changqing Oilfield to analyze the sedimentary cycles, which verified the effectiveness of the three methods, and good results were obtained.

关键词： Sedimentary cycles spectrum analysis wavelet depth-frequency analysis variable-scale frequency cycle analysis

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SUPER WOMAN 2(SPW2)maintains organ identity in spikelets by inhibiting the expression of floral homeotic genes OsMADS3,OsMADS58,OsMADS13,and DROOPING LEAF

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Journal of Integrative Agriculture 2024年第1期23卷 59-76页

作者： Hui Zhuang jinsong Lan Qiuni Yang Xiaoyu Zhao Yuhuan Li Jingya Zhi Yalin shen GuanghuaHe Yunfeng Li Rice Research Institute Key Laboratory of Application and Safety Control of Genetically Modified CropsAcademy of Agricultural SciencesSouthwest UniversityChongqing 400715China

Flower organ identity in rice is mainly determined by the A-,B-,C-and E-class genes,with the majority encoding MADS-box transcription ***,few studies have investigated how the expression of these floral organ identity genes is regulated during flower *** this study,we identified a gene named SUPER WOMAN 2(SPW2),which is necessary for spikelet/floret development in rice by participating in the regulation of the expression of pistil identity genes such as OsMADS3,OsMADS13,OsMADS58 and *** the spw2 mutant,ectopic stigma/ovary-like tissues were observed in the non-pistil organs,including sterile lemma,lemma,palea,lodicule,and stamen,suggesting that the identities of these organs were severely affected by mutations in ***2 was shown to encode a plant-specific EMF1-like protein that is involved in H3K27me3 modification as an important component of the PRC2 *** analysis showed that the SPW2 mutation led to the ectopic expression of OsMADS3,OsMADS13,OsMADS58,and DL in non-pistil organs of the *** ChIP-qPCR results showed significant reductions in the levels of H3K27me3 modification on the chromatin of these ***,we demonstrated that SPW2 can mediate the process of H3K27me3 modification of pistil-related genes to regulate their expression in non-pistil organs of spikelets in *** results of this study expand our understanding of the molecular mechanism by which SPW2 regulates floral organ identity genes through epigenetic regulation.

关键词： rice(Oryza sativa) spikelet organ identity H3K27me3

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Effect of regularization parameters on geophysical reconstruction

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Petroleum Science 2009年第2期6卷 119-126页

作者： Zhou Hui Wang Zhaolei Qiu Dongling Li Guofa shen jinsong State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Key Laboratory of CNPC Geophysical Prospecting China University of Petroleum Beijing 102249 China Research Institute Bureau of Geophysical Prospecting Hebei 072751 China China University of Petroleum Beijing 102249 China

In this paper we discuss the edge-preserving regularization method in the reconstruction of physical parameters from geophysical data such as seismic and ground-penetrating radar data. In the regularization method a potential function of model parameters and its corresponding functions are introduced. This method is stable and able to preserve boundaries, and protect resolution. The effect of regularization depends to a great extent on the suitable choice of regularization parameters. The influence of the edge-preserving parameters on the reconstruction results is investigated and the relationship between the regularization parameters and the error of data is described.

关键词： Geophysical data inversion error of data regularization regularization parameters

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从马拉默德短篇小说《湖畔淑女》看“大屠杀”与犹太身份的构建

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国外文学 2010年第2期30卷 111-118页

作者：申劲松西南大学外国语学院

"大屠杀"是犹太民族历史上最惨痛的事件,给犹太民族带来了无尽的、难以言说的创伤。但是,战后物质社会强大的同化作用却使一些犹太人在物质的浪潮之中迷失了自我,忘记自己的身份,抛弃自己的犹太性,甚至企图以摒弃自己的犹太人身份来谋... 详细信息

"大屠杀"是犹太民族历史上最惨痛的事件,给犹太民族带来了无尽的、难以言说的创伤。但是,战后物质社会强大的同化作用却使一些犹太人在物质的浪潮之中迷失了自我,忘记自己的身份,抛弃自己的犹太性,甚至企图以摒弃自己的犹太人身份来谋求与主流社会的同化,造成了拱手送给希特勒一次"死后的胜利"的危险。马拉默德通过《湖畔淑女》中男女主人公弗里曼和伊莎贝拉各自不同的选择及其结果,表达了自己对这一问题的思考,说明"大屠杀"记忆是无处不在、无时不在的,其影响不仅对于犹太人身份的坚守与维系意义重大,而且对于整个人类的道德操守也是一个衡量的标杆。

关键词： “大屠杀” 记忆身份犹太性

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频率域弹性波场模拟中高阶有限差分法的精度对比与改进策略

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中国石油大学学报（自然科学版） 2014年第5期38卷 48-58页

作者：马超沈金松李曦宁中国石油大学地球物理与信息工程学院北京102249 中国石油大学油气资源与探测国家重点实验室北京102249 中国石油大学中国石油集团公司物探重点实验室北京102249

推导基于二维交错网格的二阶和四阶频率域弹性波有限差分算子,并结合最优化差分系数和质量加权平均方法压制数值各向异性。基于均匀各向同性介质比较不同差分算子的模拟精度和频散关系,并详细比较二阶算子和四阶算子的精度和误差量级。... 详细信息

推导基于二维交错网格的二阶和四阶频率域弹性波有限差分算子,并结合最优化差分系数和质量加权平均方法压制数值各向异性。基于均匀各向同性介质比较不同差分算子的模拟精度和频散关系,并详细比较二阶算子和四阶算子的精度和误差量级。结果表明,当采用交错网格最优化四阶差分算子,单位横波波长内含3个及以上网格点时,可将模拟误差控制在2%以内。同时,相对于常规网格,基于交错网格的差分算子可用于对含流体介质模型的模拟。

关键词：频率域交错网格有限差分算子数值各向异性

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Design of high-performance and sustainable Co-free Ni-rich cathodes for next-generation lithium-ion batteries

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SusMat 2024年第1期4卷 48-71页

作者： Hao Ge Zhiwen shen Yanhong Wang Zhijia Sun Xiaoman Cao Chaoyue Wang Xinyue Fan jinsong Bai Rundong Li Tianhua Yang Gang Wu School of Energy and Environment Shenyang Aerospace UniversityShenyangP.R.China shenyang Aircraft Airworthiness Certification Center of CAAC ShenyangP.R.China College of Chemistry and Materials Engineering Bohai UniversityJinzhouP.R.China Liaoning General Aviation Academy ShenyangP.R.China Department of Chemical and Biological Engineering University at BuffaloState University of New YorkBuffaloNew YorkUSA

Great attention has been given to high-performance and inexpensive lithiumion batteries(LIBs)in response to the ever-increasing demand for the explosive growth of electric vehicles(EVs).High-performance and low-cost Co-freeNi-rich layered cathodes are considered one of the most favorable candidates for nextgeneration LIBs because the current supply chain of EVs relies heavily on scarce and expensive ***,we review the recent research progress on Co-free Nirich layered cathodes,emphasizing on analyzing the necessity of replacing Co and the popular improvment *** current advancements in the design strategies of Co-free Ni-rich layered cathodes are summarized in *** considerable improvements achieved so far,the main technical challenges contributing to the deterioration of Co-free Ni-rich cathodes such as detrimental phase transitions,crack formation,and severe interfacial side reactions,are difficult to resolve by a single *** cooperation of multiple modification strategies is expected to accelerate the industrialization of Co-free Ni-rich layered cathodes,and the corresponding synergistic mechanisms urgently need to be *** effects will be aroused to explore high-performance Co-free Ni-rich layered cathodes to promote the sustainable development of LIBs.

关键词： Co-free cathodes electrochemical performance lithium-ion batteries modification strategies Ni-rich layered cathodes

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Association between serum metal element levels and the severity of acute traumatic brain injury

Association between serum metal element levels and the sever...

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2019年浙江省医学会老年精神障碍学术大会

作者： Zhengping Pu Yong Lin Zhibiao Chen Jianxiang Wu jinsong shen Department of Encephalopathy Kangci Hospital of Jiaxing Department of Neurosurgery the Second People's Hospital of Tongxiang Department of Emergency the Second Hospital of Jiaxing Department of Intensive Care Unit the First People's Hospital of Tongxiang

Objective:Serum metal elements are involved in the pathophysiological processes of traumatic brain injury (TBI). This study was aimed at investigating the serum levels of metal elements in patients with acute TBI. The correlation between serum metal element levels and the severity of acute TBI was ***:Sixty-eight consecutive patients with acute TBI were enrolled. The patients were classified into three groups for TBI severity according to the Glasgow Coma Scale (GCS): mild (n=38), moderate (n=8), and severe (n=22). Serum copper, iron, zinc, calcium, and magnesium levels were ***:Serum copper levels were significantly higher in normal controls than in patients with TBI. Compared to the normal controls, serum iron and zinc levels were significantly lower in patients with TBI. Compared to the controls and patients with mild TBI, serum magnesium levels were significantly lower in the moderate and severe TBI groups. The severity of TBI was positively correlated with serum magnesium and zinc levels. Serum iron and magnesium levels were independent protective factors against ***:Serum metal element levels are closely associated with the severity of acute TBI. Measurement of serum metal element levels may provide an alternative approach for evaluating the severity of acute TBI.

关键词： traumatic brain injury metal element severity acute phase

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