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鼎湖山南亚热带森林群落演替对土壤化学性质影响的累积效应研究

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水土保持学报 2003年第4期17卷 51-54页

作者：欧阳学军黄忠良周国逸褚国伟李炯史军辉徐国良中国科学院华南植物研究所广州510650

比较研究了南亚热带鼎湖山森林群落演替序列中马尾松林、针阔混交林和季风常绿阔叶林表层(0～20cm)土壤pH值、有机质、全N、速效K、交换性Ca和Mg、有效P、B、Mo、Cu、Fe、Zn和易还原Mn等营养元素的含量及其相关关系,结果表明:马尾松林土... 详细信息

比较研究了南亚热带鼎湖山森林群落演替序列中马尾松林、针阔混交林和季风常绿阔叶林表层(0～20cm)土壤pH值、有机质、全N、速效K、交换性Ca和Mg、有效P、B、Mo、Cu、Fe、Zn和易还原Mn等营养元素的含量及其相关关系,结果表明:马尾松林土壤pH值显著高于其它两森林土壤;随着群落的进展演替,养分在土壤中的累积(Ca除外)呈不断增加的趋势,即马尾松林<针阔叶混交林<季风常绿阔叶林;不同指标的累积呈现出持续增加(有机质、交换性Mg、有效B、Mo、Cu、Fe和易还原Mn)、持续递减(交换性Ca)、先增加再减少(有效P)和先减少再增加(pH值、总N和有效Zn)的4种变化形式;土壤养分元素的相关对对数以马尾松林最多。植物对土壤性质的影响累积效应显著,森林群落的进展演替过程是土壤养分不断积累的过程,土壤有效养分元素来源也趋多元化。

关键词：鼎湖山南亚热带森林群落演替土壤化学性质累积效应土壤pH值土壤养分

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直肠癌新辅助治疗后淋巴结转移相关因素分析

癌症 2009年第9期28卷 923-927页

作者：曾智帆丁培荣潘志忠林俊忠李力人卢震海伍小军孔令亨周仲国万德森华南肿瘤学国家重点实验室广东广州510060 中山大学肿瘤防治中心放疗科广东广州510060 中山大学肿瘤防治中心结直肠科广东广州510060

背景与目的:新辅助治疗(放疗或放化疗)可使直肠癌的浸润深度和淋巴结转移状况都发生改变,而淋巴结转移情况对直肠癌的新辅助治疗方案的选择及后继治疗方案的选择有重要参考作用。本研究的目的是通过回顾性分析了解直肠癌新辅助治疗后影... 详细信息

背景与目的:新辅助治疗(放疗或放化疗)可使直肠癌的浸润深度和淋巴结转移状况都发生改变,而淋巴结转移情况对直肠癌的新辅助治疗方案的选择及后继治疗方案的选择有重要参考作用。本研究的目的是通过回顾性分析了解直肠癌新辅助治疗后影响淋巴结转移的相关因素。方法:收集2003年8月至2008年2月接受新辅助治疗及TME手术的中低位直肠癌病例93例,建立数据库。选择年龄、性别、肿瘤距肛缘距离、组织类型、新辅助治疗后T分期(ypT分期)、放疗前血清癌胚抗原(carcinoembryonic antigen,CEA)水平和CA19-9水平、放疗后血清CEA水平和CA19-9水平、放射剂量、接受含奥沙利铂方案的同期化疗与否、放射治疗与手术的时间间距等12项临床病理指标及治疗参数,用单因素分析和多因素分析的方法研究各因素对93例行新辅助治疗的直肠癌患者淋巴结转移情况的影响。结果:单因素分析显示,放疗后血清CEA水平、放射剂量、放射治疗与手术的时间间距、接受含奥沙利铂方案的同期化疗以及ypT分期是新辅助治疗后淋巴结转移情况(ypN分期)的相关因素。有序反应变量Logistic回归模型多因素分析显示,接受同期含奥沙利铂方案化疗及术后T分期是淋巴结转移的独立影响因素,相关系数分别为-0.481和0.503。结论:直肠癌新辅助治疗后ypT分期仍与ypN分期相关,ypT0-1患者淋巴结转移率低。含奥沙利铂的同期化疗可显著降低淋巴结转移的风险,有改善预后的潜在优势。

关键词：直肠肿瘤新辅助治疗淋巴结转移多因素分析

Direct regeneration of LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) cathode material from spent lithium-ion batteries

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Chinese Journal of Chemical Engineering 2021年第12期34卷 278-286页

作者： Xiaodong Tang Qiankun guo Miaomiao zhou Shengwen zhong Faculty of Materials Melallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

At present,metal ions from spent lithium-ion batteries are mostly recovered by the acid leaching procedure,which unavoidably introduces potential pollutants to the ***,it is necessary to develop more direct and effective green recycling *** this research,a method for the direct regeneration of anode materials is reported,which includes the particles size reduction of recovered raw materials by jet milling and ball milling,followed by calcination at high temperature after lithium *** regenerated LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) single-crystal cathode material possessed a relatively ideal layered structure and a complete surface morphology when the lithium content was n(Ni+Co+Mn):n(Li)=1:1.10 at a sintering temperature of 920 0 C,and a sintering time of 12 *** first discharge specific capacity was 154.87 mA·h·g^(-1) between 2.75 V and 4.2 V,with a capacity retention rate of 90% after 100 cycles.

关键词： Spent lithium-ion batteries LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)cathode material Direct regeneration

Supersymmetry and Solution of Dirac Equation with Vector and Scalar Potentials

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Communications in Theoretical Physics 2008年第2期49卷 319-326页

作者： JU guo-Xing REN zhong-zhou Department of Physics Nanjing University Nanjing 210093 China

The Dirac equations with vector and scalar potentials of the Coulomb types in two and three dimensions are solved using the supersymmetric quantum mechanics method. For the system of such potentials, the analytical ex... 详细信息

关键词： Dirac equation vector potential scalar potential supersymmetry matrix element

Linear random search and engineering estimation of sinkage for launching carrier aircraft

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Science China(Technological Sciences) 2019年第6期62卷 996-1002页

作者： zhong guo HUANG Jun zhou ZeYang YI MingXu School of Aeronautic Science and Engineering Beijing University of Aeronautics and Astronautics

A linear random search algorithm(LRSA) is developed to determine the critical value of takeoff weight limited to the safe flight track sinkage and an engineering estimation method(EEM) is proposed to calculate the sinkage of carrier aircraft launch in real time. Based on the analysis of free flight after leaving the carrier, the equations are established to participate into engineering estimation of flight track sinkage. Thanks to the proposed search algorithm, the maximum takeoff weight of carrier aircraft with safe catapult launch flight track sinkage is generated in few steps. The results of sinkage estimation and the search algorithm are in good agreement with that of aircraft catapult launch simulation. The main contribution of this manuscript is the establishment of simple and accurate engineering estimation for carrier aircraft launch flight track sinkage and the development of robust and efficient search algorithm for the critical value with safe catapult criteria.

关键词： carrier aircraft launch flight track sinkage engineering estimation linear random search simulation

Localization of s-Wave and Quantum Effective Potential of a Quasi-free Particle with Position-Dependent Mass

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Communications in Theoretical Physics 2006年第5X期46卷 819-825页

作者： JU guo-Xing XIANG Yang REN zhong-zhou Department of Physics Nanjing University Nanjing 210093 China

The properties of the 8-wave for a quasl-free partide with position-dependent mass （PDM） have been discussed in details. Differed from the system with constant mass in which the localization of the s-wave for the free quantum particle around the origin only occurs in two dimensions, the quasi-free particle with PDM can experience attractive forces in D dimensions except D = 1 when its mass function satisfies some conditions. The effective mass of a particle varying with its position can induce effective interaction, which may be attractive in some cases. The analytical expressions of the eigenfunctions and the corresponding probability densities for the 8-waves of the two- and three-dimensional systems with a special PDM are given, and the existences of localization around the origin for these systems are shown.

关键词： position-dependent mass s-wave Schrodinger equation dimensionality of the space localization eigenfunction probability density

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一种飞行时间法读出电路

核电子学与探测技术 1988年第2期 71-76页

作者：方澄钟戈平高美丽周鸣中国科学院高能物理所

本文介绍了北京谱仪飞行时间法电子学中的读出电路部分。它同时测量闪烁探测器的信号到达时间和信号的电荷量,以利用电荷量对时间移动进行离线修正。

关键词：飞行时间法读出电路测量

Forest succession trajectories after fi res in valleys and on slopes in the Greater Khingan Mountains,China

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Journal of Forestry Research 2023年第3期34卷 623-640页

作者： Chao zhong Meng guo Fenfen zhou Jianuo Li Fangbing Yu Futao guo Wenshan Li Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024People’s Republic of China College of Forestry Fujian Agriculture and Forestry UniversityFuzhou 350002People’s Republic of China Huzhong Nature Reserve Administration of Heilongjiang Province Huzhong 165033People’s Republic of China

Accurate assessment of postfire vegetation recovery is important for forest management and the conservation of species *** is an important factor aff ecting vegetation recovery but whether species composition varies with diff erent recovery stages and between valleys and slopes is *** fi eld data and a space-for-time substitution method,we quantifi ed species richness and diversity to obtain the successional trajectories of valleys and *** surveyed the species of 10 burned areas from 1986 to 2010 in the Greater Khingan Mountains in northeastern China,and found that with increasing postfi re recovery time,species richness in both valleys and slopes gradually ***,species richness in valleys was relatively *** recovered rapidly in the valleys,and species diversity maximized approximately 11 years after fi ***,it maximized 17–18 years after fi re on the *** shade-tolerant species were present in the valleys 11 years after fi re but not until after 18 years on *** appeared earlier than 11 years after fi re and its recovery was slow in the valleys but appeared quickly on slopes and established dominance *** study provides some new insights into vegetation succession after fi re at local *** fi re,the vegetation recovery processes diff er with topography and it aff ects the initial rate of recovery and species composition at diff erent successional stages.

关键词： Vegetation recovery Valleys and slopes Space-for-time substitution Species richness/diversity/composition Greater Khingan Mountains

Generalized Harmonic Oscillator and the Schrdinger Equation with Position-Dependent Mass

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Communications in Theoretical Physics 2009年第5期51卷 797-802页

作者： JU guo-Xing CAI Chang-Ying REN zhong-zhou Department of Physics Nanjing University Nanjing 210093 China Department of Physics Jinggangshan University Ji＇an 343009 China

We study the generalized harmonic oscillator that has both the position-dependent mass and the potential depending on the form of mass function in a more general framework. The explicit expressions of the eigenvalue and eigenfunction for such a system are given, they have the same forms as those for the usual harmonic oscillator with constant mass. The coherent state and its properties corresponding effective potentials for several mass functions, for the system with PDM are also discussed. We give the the systems with such potentials are isospectral to the usual harmonic oscillator.

关键词： generalized harmonic oscillator Schr6dinger equation position-dependent mass coherent state