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Simulation of Potential Production and Optimum Population Quantitative Indices for the Second Hybrid Rice 被引量:1
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作者 YAN Li-Jiao YAO Zhong ZHENG Zhi-ming LI Hua-bin 《Agricultural Sciences in China》 CAS CSCD 2006年第7期498-505,共8页
The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, ... The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, daily dry matter accumulation and partitioning, daily CO2 assimilation of the canopy, leaf area, and tiller development. The model preferably simulated the dynamic rice development because of the thorough integration of the effects of temperature and light on the rates of rice development, photosynthesis, respiration, and. other ecophysiological processes. In addition, this model has attainable grain yield in the test experiment that showed the potential yield of cultivar Xieyou 46 ranged from 11 to 13 tons ha-~. Besides, the model was used to optimize the combinations of the transplanting date, seedling age and density for cultivar Xieyou 46 at Jinhua area, and the population quantitative indices to attain the potential yield such as maximum stems, effective panicles, filled grain number/leaf area, and so on. The result showed that the combination of transplanting date on July 25, seedling age of 35 days and base seedling density of 1.33 x 106ha-1 is the optimum combination for the second hybrid rice production in Jinhua County, China. And the maximum stems, the effective panicles, the filled grain per panicle, the peak of optimum LAI, LAI in later filling stage, and the filled grain number/leaf were 6.03×10^6ha, 3.99×10^6ha, 119.2, 8.59, 5-6, and 0.64, respectively. 展开更多
关键词 SIMULATION MODEL potential production optimum population quantitative indices second hybrid rice
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A Multi-Square-Well Potential Model and Its Application in Calculating the Second Virial Coefficient
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作者 苏志军 严家 +1 位作者 曾向东 尚德敏 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1994年第2期15-20,共6页
AMulti-Square-WellPotentialModelandItsApplicationinCalculatingtheSecondVirialCoefficient¥(苏志军)(严家)(曾向东)(尚德敏)... AMulti-Square-WellPotentialModelandItsApplicationinCalculatingtheSecondVirialCoefficient¥(苏志军)(严家)(曾向东)(尚德敏)SUZhijun;YANJialu... 展开更多
关键词 ss: Molecular potential SQUARE-WELL potential MODEL second VIRIAL COEFFICIENT
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Relativistic treatment of the spin-zero particles subject to the second Pschl Teller-like potential
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作者 Ekele V.Aguda Amos S.Idowu 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期101-106,共6页
The three-dimensional Klein-Gordon equation is solved for the case of equal vector and scalar second Poschl-Teller potential by proper approximation of the centrifugal term within the framework of the asymptotic itera... The three-dimensional Klein-Gordon equation is solved for the case of equal vector and scalar second Poschl-Teller potential by proper approximation of the centrifugal term within the framework of the asymptotic iteration method. Energy eigenvalues and the corresponding wave function are obtained analytically. Eigenvalues are computed numerically for some values of n and It is found that the results are in good agreement with the findings of other methods for short-range potential. 展开更多
关键词 second P6schl-Teller potential asymptotic iteration EIGENVALUES EIGENFUNCTION
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Generalization of the Second Order Vector Potential Formulation for Arbitrary Non-Orthogonal Curvilinear Coordinates Systems from the Covariant Form of Maxwell's Equations
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作者 Denis Prémel 《Journal of Electromagnetic Analysis and Applications》 2012年第10期400-409,共10页
A great number of semi-analytical models, notably the representation of electromagnetic fields by integral equations are based on the second order vector potential (SOVP) formalism which introduces two scalar potentia... A great number of semi-analytical models, notably the representation of electromagnetic fields by integral equations are based on the second order vector potential (SOVP) formalism which introduces two scalar potentials in order to obtain analytical expressions of the electromagnetic fields from the two potentials. However, the scalar decomposition is often known for canonical coordinate systems. This paper aims in introducing a specific SOVP formulation dedicated to arbitrary non-orthogonal curvilinear coordinates systems. The electromagnetic field representation which is derived in this paper constitutes the key stone for the development of semi-analytical models for solving some eddy currents moelling problems and electromagnetic radiation problems considering at least two homogeneous media separated by a rough interface. This SOVP formulation is derived from the tensor formalism and Maxwell’s equations written in a non-orthogonal coordinates system adapted to a surface characterized by a 2D arbitrary aperiodic profile. 展开更多
关键词 second Order Vector potential (SOVP) Curvilinear COORDINATE System EDDY Current NON-DESTRUCTIVE Testing (ECNDT)
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Second-Order Potentials and Forces for Two-Dimensional Diffraction Problem of Finite Water Depth
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作者 Duan Wenyang and He Wuzhou Graduate student, Department of Naval Architecture and Ocean Engineering, Harbin Engineering University, Harbin 150001 . Associate Professor, Department of Hydraulic Engineering, Tsinghua University 《China Ocean Engineering》 SCIE EI 1994年第3期321-330,共10页
-In this paper, an analytical solution in the outer region of finite water depth is derived for the second-order diffraction potential, which gives a clear physical meaning of the wave transmission and reflection char... -In this paper, an analytical solution in the outer region of finite water depth is derived for the second-order diffraction potential, which gives a clear physical meaning of the wave transmission and reflection characteristics in the far field. A numerical method-simple Green's function technique-for calculating the second-order diffraction potential in the inner region is also described. Numerical results are provided for the second-order wave forces on a semi-submerged cylinder. It is found that the contribution of second-order diffraction potential to second-order wave forces is important. The effect of water depth and submerged depth on the wave force is also discussed. 展开更多
关键词 second-order diffraction potential second-order wave forces
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Exact solutions of the Dirac equation with Pschl-Teller double-ring-shaped Coulomb potential via the Nikiforov-Uvarov method 被引量:2
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作者 E.Maghsoodi H.Hassanabadi S.Zarrinkamar 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期117-121,共5页
Exact analytical solutions of the Dirac equation are reported for the Poschl-Teller double-ring-shaped Coulomb potential.The radial,polar,and azimuthal parts of the Dirac equation are solved using the Nikiforov-Uvarov... Exact analytical solutions of the Dirac equation are reported for the Poschl-Teller double-ring-shaped Coulomb potential.The radial,polar,and azimuthal parts of the Dirac equation are solved using the Nikiforov-Uvarov method,and the exact bound-state energy eigenvalues and corresponding two-component spinor wavefunctions are reported. 展开更多
关键词 Dirac equation poschl-teller double-ring-shaped Coulomb potential Nikiforov-Uvarov method
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Bound states of the Schrdinger equation for the Pschl-Teller double-ring-shaped Coulomb potential
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作者 陆法林 陈昌远 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期88-93,共6页
Poschl-Teller double-ring-shaped Coulomb (PTDRSC) potential, the Coulomb potential surrounded by PSschl- Teller and double-ring-shaped inversed square potential, is put forward. In spherical polar coordinates, PTDRS... Poschl-Teller double-ring-shaped Coulomb (PTDRSC) potential, the Coulomb potential surrounded by PSschl- Teller and double-ring-shaped inversed square potential, is put forward. In spherical polar coordinates, PTDRSC potential has supersymmetry and shape invariance in φ,θ and τ coordinates. By using the method of supersymmetry and shape invariance, exact bound state solutions of Schr6dinger equation with PTDRSC potential are presented. The normalized φ,θ angular wave function expressed in terms of Jacobi polynomials and the normalized radial wave function expressed in terms of Laguerre polynomials are presented. Energy spectrum equations are obtained. Wave function and energy spectrum equations of the system are related to three quantum numbers and parameters of PTDRSC potential. The solutions of wave functions and corresponding eigenvalues are only suitable for the PTDRSC potential. 展开更多
关键词 poschl-teller double-ring-shaped Coulomb potential supersymmetry and shape invari-ance Schrodinger equation bound states
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Theorem of Necessity and Sufficiency of Stable Equilibrium for Generalized Potential Equality between System and Reservoir
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作者 Pierfrancesco Palazzo 《Journal of Modern Physics》 2014年第18期2003-2011,共9页
The literature reports that equality of temperature, equality of potential and equality of pressure between a system and a reservoir are necessary conditions for the stable equilibrium of the system-reservoir composit... The literature reports that equality of temperature, equality of potential and equality of pressure between a system and a reservoir are necessary conditions for the stable equilibrium of the system-reservoir composite or, in the opposite and equivalent logical inference, that stable equilibrium is a sufficient condition for equality. The aim and the first novelty of the present study is to prove that equality of temperature, potential and pressure is also a sufficient condition for stable equilibrium, in addition to necessity, implying that stable equilibrium is a condition also necessary, in addition to sufficiency, for equality. The second novelty is that the proof of the sufficiency of equality (or the necessity of stable equilibrium) is attained by means of the generalization of the entropy property, derived from the generalization of exergy property, which is used to demonstrate that stable equilibrium is a logical consequence of equality of generalized potential. This proof is underpinned by the Second Law statement and the Maximum-Entropy Principle based on generalized entropy which depends on temperature, potential and pressure of the reservoir. The conclusion, based on these two novel concepts, consists of the theorem of necessity and sufficiency of stable equilibrium for equality of generalized potentials within a composite constituted by a system and a reservoir. 展开更多
关键词 Available Energy second Law Stable EQUILIBRIUM NONEQUILIBRIUM GENERALIZED EXERGY GENERALIZED Entropy GENERALIZED potential
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苏北盆地溱潼凹陷沙垛1井侵入岩岩石学特征及其储集性与含油性研究
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作者 夏祥 马晓东 +1 位作者 胡文瑄 臧素华 《石油实验地质》 CAS CSCD 北大核心 2024年第1期87-97,共11页
火成岩油气藏逐渐成为重要的油气藏类型,但火成岩储层非均质性很强,储集性能变化很大,储层成因机制研究非常薄弱,成为制约火成岩储层评价的主要瓶颈。以苏北盆地溱潼凹陷古近系阜宁组二段侵入岩为研究对象,通过系统的岩心观察、薄片鉴... 火成岩油气藏逐渐成为重要的油气藏类型,但火成岩储层非均质性很强,储集性能变化很大,储层成因机制研究非常薄弱,成为制约火成岩储层评价的主要瓶颈。以苏北盆地溱潼凹陷古近系阜宁组二段侵入岩为研究对象,通过系统的岩心观察、薄片鉴定、电子探针分析测试和测井解释等,剖析了溱潼凹陷沙垛1井阜二段侵入岩岩性、岩相特征、储层特征和储层发育主控因素。结果表明:该区侵入岩的岩性纵向变化显著,由多期侵入岩叠加组成,顶部为辉绿岩,中部为辉石二长岩,下部为橄榄辉长岩;孔隙发育程度不均一,辉绿岩和辉石二长岩孔隙发育程度低,而橄榄辉长岩孔隙发育程度较高;由于多期侵入作用的叠加以及热液蚀变的改造,发育了较好的储集空间。孔隙类型主要为溶蚀孔和构造裂缝,还发育收缩裂缝。影响储层物性的主要因素是岩性和热液流体活动,其中橄榄辉长岩中辉石等暗色矿物最易蚀变,溶蚀孔发育程度高;此外,区域性的断裂构造在许多致密的火成岩中产生了大量的构造裂缝,有效沟通了侵入岩储层的孔缝系统,且为后期的溶蚀作用提供了岩浆热液流动的通道。沙垛1井钻遇的侵入岩总体上含油性差,下部侵入岩层中可见零星荧光显示,上部侵入岩层中基本不含油。 展开更多
关键词 侵入岩储层特征 含油性 阜宁组二段 溱潼凹陷 苏北盆地
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Second life教育潜能研究及其对远程教育的启示 被引量:10
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作者 李振亭 毛颖颖 《现代教育技术》 CSSCI 2008年第1期81-83,共3页
Second life是目前国外在企业、教育等众多领域得到广泛应用的平台。该文通过对Second life及其特点的研究,详细探讨了Second life在教育领域内应用的潜能,进而探索该研究对当前远程教育的启示。
关键词 second LIFE 教育潜能 远程教育
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沧东凹陷孔二段页岩生排烃效率及对含油性的影响
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作者 冯家乐 杨升宇 +6 位作者 胡钦红 马斌玉 文家成 王旭阳 蒲秀刚 韩文中 张伟 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第2期45-56,共12页
渤海湾盆地沧东凹陷孔二段页岩油资源潜力巨大,且通过水平井钻控获得了稳产工业油流。应用常规热解和分步热解技术,优化生排烃物质平衡法,提出了基于原始生烃潜力和现今残余生烃潜力的页岩生烃和排烃效率氢指数平衡计算方法,并探索成熟... 渤海湾盆地沧东凹陷孔二段页岩油资源潜力巨大,且通过水平井钻控获得了稳产工业油流。应用常规热解和分步热解技术,优化生排烃物质平衡法,提出了基于原始生烃潜力和现今残余生烃潜力的页岩生烃和排烃效率氢指数平衡计算方法,并探索成熟度以外孔二段页岩排烃效率的主控因素及其与含油性的关系。选取深度和成熟度较为接近的样品,以排除成熟度这一公认的生排烃效率指标的影响。结果表明,页岩有机质丰度和类型、微观孔隙结构和岩石类型等是控制其生排烃效率的重要因素。Ⅲ型干酪根产物以轻烃为主,排烃效率变化大且普遍高于Ⅰ型和Ⅱ型干酪根。Ⅰ型和Ⅱ型干酪根在TOC超过3%以后,排烃效率随TOC的增加而增大。墨水瓶型孔对液态烃的滞留能力强于狭缝型孔;对气态烃而言墨水瓶型孔反而是利于排烃的优势通道。纹层状页岩比薄层状页岩具有更低的排烃效率。生排烃共同控制着页岩的含油量,页岩中含油量与排烃效率整体呈负相关,但与生烃潜力、生烃效率和滞留烃率的乘积呈明显的正相关性,展示了生排烃效率计算方法的可靠性和实用性。 展开更多
关键词 沧东凹陷 孔二段 页岩油 排烃效率 含油量 生烃潜力平衡法
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Mg-9Al-4Ca-2Cu合金的制备及其组织性能
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作者 张庆辉 范舟 +1 位作者 侯涛 田波 《南方金属》 CAS 2024年第4期8-14,共7页
制备一种合金用于减弱腐蚀给油气田带来的影响。利用等离子放电烧结炉(SPS),在Mg基础上添加Al、Ca、Cu元素制备成Mg-9Al-4Ca-2Cu合金,获得第二相Mg_(2)Ca和Mg_(2)Cu;利用现代分析技术进行观察和分析,利用N80钢对合金防腐性能进行表征。... 制备一种合金用于减弱腐蚀给油气田带来的影响。利用等离子放电烧结炉(SPS),在Mg基础上添加Al、Ca、Cu元素制备成Mg-9Al-4Ca-2Cu合金,获得第二相Mg_(2)Ca和Mg_(2)Cu;利用现代分析技术进行观察和分析,利用N80钢对合金防腐性能进行表征。结果表明:经过合金处理后,N80钢自身耐蚀性变好,腐蚀电压由-0.672 V变为-0.452 V;腐蚀电流由1.572×10^(-5)A·cm^(-2)变为8.1×10^(-6)A·cm^(-2)。通过第一性原理计算基体相以及第二相的电子功函数获得第二相与基体相之间的电势差,结果显示:α-Mg与Mg_(2)Ca之间的电势差为-750~-460 mV、α-Mg与Mg_(2)Cu之间的电势差-392~106 mV,构成两对电偶腐蚀,可以向溶液中释放多余电子,从而抑制阳极金属溶解。 展开更多
关键词 油田防腐 第二相 释放电子 电势差
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Modified 2CLJDQP model and the second virial coefficients for linear molecules 被引量:1
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作者 张颖 王升 何茂刚 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期316-323,共8页
A modified form of 2CLJDQP potential model is proposed to calculate the second virial coefficients of two-center Lennard-Jones molecules. In the presented potential model, the potential parameters σ and ε are consid... A modified form of 2CLJDQP potential model is proposed to calculate the second virial coefficients of two-center Lennard-Jones molecules. In the presented potential model, the potential parameters σ and ε are considered as the temperature-dependent parameters in the form of hyperbolical temperature function based on the theory of temperaturedependent potential parameters. With this modified model, the second virial coefficients of some homonuclear molecules(such as O2, Cl2, CH3CH3, and CF3CF3) and heteronuclear molecules(such as CO, NO, CH3 F, CH3 Cl, CH3CF3,CH3CHF2, and CF3CH2F) are calculated. Then the Lorentz–Berthelot mixing rule is modified with a temperaturedependent expression, and the second virial coefficients of the heteronuclear molecules(such as CH3 F, CH3 Cl, and CH3CF3) are calculated. Moreover, CO2 and N2O are also studied with the modified 3CLJDQP model. The calculated results from the modified 2CLJDQP model accord better with the experimental data than those from the original model.It is shown that the presented model improves the positive deviation in low temperature range and negative deviation in high temperature range. So the modified 2CLJDQP potential model with the temperature-dependent parameters can be employed satisfactorily in large temperature range. 展开更多
关键词 potential function temperature-dependent parameters linear molecules second virial coefficients
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Seismic inversion with generalized Radon transform based on local second-order approximation of scattered field in acoustic media
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作者 Wei Ouyang Weijian Mao +1 位作者 Xuelei Li Wuqun Li 《Earthquake Science》 2014年第4期433-439,共7页
Sound velocity inversion problem based on scattering theory is formulated in terms of a nonlinear integral equation associated with scattered field. Because of its nonlinearity, in practice, linearization algorisms (... Sound velocity inversion problem based on scattering theory is formulated in terms of a nonlinear integral equation associated with scattered field. Because of its nonlinearity, in practice, linearization algorisms (Born/ single scattering approximation) are widely used to obtain an approximate inversion solution. However, the linearized strategy is not congruent with seismic wave propagation mechanics in strong perturbation (heterogeneous) medium. In order to partially dispense with the weak perturbation assumption of the Born approximation, we present a new approach from the following two steps: firstly, to handle the forward scattering by taking into account the second- order Born approximation, which is related to generalized Radon transform (GRT) about quadratic scattering poten- tial; then to derive a nonlinear quadratic inversion formula by resorting to inverse GRT. In our formulation, there is a significant quadratic term regarding scattering potential, and it can provide an amplitude correction for inversion results beyond standard linear inversion. The numerical experiments demonstrate that the linear single scattering inversion is only good in amplitude for relative velocity perturbation (3c/c0) of background media up to 10 %, andits inversion errors are unacceptable for the perturbation beyond 10 %. In contrast, the quadratic inversion can give more accurate amplitude-preserved recovery for the per- turbation up to 40 %. Our inversion scheme is able to manage double scattering effects by estimating a trans- mission factor from an integral over a small area, and therefore, only a small portion of computational time is added to the original linear migration/inversion process. 展开更多
关键词 Scattering potential second-order Bornapproximation True-amplitude inversion
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以科技教育观点初探Second Life与在线游戏之意涵
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作者 方瑀绅 张畹蚯 《现代教育技术》 CSSCI 2011年第2期90-93,共4页
该研究从在线游戏对青少年迷恋之相关因子与游戏不受教育界重视之原因切入,随即说明Second Life与在线游戏之差异及教育内涵,有助于从事在线游戏教学者一个参考资料。
关键词 第二生命 在线游戏 情境学习 教育潜能
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The SLA (Second Law Analysis) in Convective Heat Transfer Processes
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作者 Heinz Herwig 《Journal of Energy and Power Engineering》 2016年第5期283-286,共4页
关键词 对流换热 换热过程 第二定律 SLA 熵产生率 温度场 损失 热力学
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基于二次有机气溶胶和臭氧生成潜势的河北挥发性有机物优控物种研究 被引量:3
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作者 刘新军 王淑娟 +1 位作者 范莉茹 宿文康 《环境污染与防治》 CAS CSCD 北大核心 2023年第2期183-187,193,共6页
为研究河北大气中挥发性有机物(VOCs)对臭氧(O_(3))及二次有机气溶胶(SOA)生成的影响,利用2021年4—10月河北11个地市VOCs的监测数据,对河北VOCs污染特征及其关键活性组分进行分析研究。结果表明,观测期间河北VOCs平均体积分数为36.16&#... 为研究河北大气中挥发性有机物(VOCs)对臭氧(O_(3))及二次有机气溶胶(SOA)生成的影响,利用2021年4—10月河北11个地市VOCs的监测数据,对河北VOCs污染特征及其关键活性组分进行分析研究。结果表明,观测期间河北VOCs平均体积分数为36.16×10^(-9),低碳的醛酮类和低碳的烷烃是河北VOCs的主要构成物种。VOCs高值区主要集中在河北中南部沧州、衡水、邯郸、石家庄等地,北部城市秦皇岛、张家口VOCs浓度较低。监测期间,河北O_(3)生成潜势(OFP)为259.67μg/m^(3),SOA生成潜势为0.61μg/m^(3),其中衡水OFP最高,达302.96μg/m^(3),石家庄SOA生成潜势最高,达0.92μg/m^(3)。甲苯、间/对二甲苯和邻二甲苯对OFP及SOA生成潜势的贡献均较大,是O_(3)和大气颗粒物协同控制的优控VOCs物种。 展开更多
关键词 河北 挥发性有机物 臭氧生成潜势 二次有机气溶胶
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句子理解过程中敬语加工和词类加工的交互作用:来自ERPs的证据 被引量:1
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作者 纪丽燕 冀爱爱 《心理与行为研究》 北大核心 2023年第2期169-176,共8页
采用事件相关电位(ERPs)技术,通过同时操纵名词短语中听话人社会地位和话语中第二人称代词形式“你/您”的一致性以及名词短语中词类的一致性,考察句子理解过程中敬语加工和词类加工的交互作用。研究结果显示,在词类一致条件下,敬语违... 采用事件相关电位(ERPs)技术,通过同时操纵名词短语中听话人社会地位和话语中第二人称代词形式“你/您”的一致性以及名词短语中词类的一致性,考察句子理解过程中敬语加工和词类加工的交互作用。研究结果显示,在词类一致条件下,敬语违反在高语用能力组诱发P600,低语用能力组诱发左侧前部负波(LAN)和晚期负活动;词类违反的条件下,两组被试中均没有发现和敬语违反加工相关的ERP效应,词类违反和词类-敬语双重违反在两组被试中均诱发P600效应。结果表明,在语言理解过程中,敬语的加工必须在成功的、基于词类的短语结构建构的基础上进行;敬语一致性的加工策略受到个体语用能力的调节。 展开更多
关键词 词类 第二人称代词 敬语 语用 事件相关电位
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Second order potential vorticity and its potential applications 被引量:2
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作者 GAO ShouTing XU PengCheng +1 位作者 LI Na ZHOU YuShu 《Science China Earth Sciences》 SCIE EI CAS 2014年第10期2428-2434,共7页
A new invariant, the second order potential vorticity(SPV), is derived in this paper. SPV is the dot product of vorticity and the potential vorticity(PV) gradient, and is proven conservative for a compressible, adiaba... A new invariant, the second order potential vorticity(SPV), is derived in this paper. SPV is the dot product of vorticity and the potential vorticity(PV) gradient, and is proven conservative for a compressible, adiabatic and frictionless atmosphere. Research shows that the new invariant may be used to indicate the evolution of PV, because SPV includes all the information that determines PV evolution: the wind field, and the PV gradient. Furthermore, SPV is capable of diagnosing heavy precipitation because of the strong signals it presents in areas of heavy rainfall. SPV also shows great potential as a comprehensive conserved quantity for indicating the dynamical tropopause and baroclinic instability. 展开更多
关键词 位涡 二阶 应用 SPV 斜压不稳定 对流层顶 不变量 可压缩
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A new many-body potential with the second-moment approximation of tight-binding scheme for Hafnium 被引量:1
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作者 LIN DeYe WANG Yi +3 位作者 SHANG ShunLi LU ZhaoPing LIU ZiKui HUI XiDong 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第11期2071-2080,共10页
In this work,we develop a new many-body potential for alpha-hafnium(α-Hf)based on the second moment approximation of tight-binding(TB-SMA)theory by introducing an additional Heaviside step function into the potential... In this work,we develop a new many-body potential for alpha-hafnium(α-Hf)based on the second moment approximation of tight-binding(TB-SMA)theory by introducing an additional Heaviside step function into the potential model and a new analytical scheme of density function.All the parameters of the new potential have been systematically evaluated by fitting to ground-state properties including cohesive energy,lattice constants,elastic constants,vacancy formation energy,structure stability and equation of state.By using the present model,the melting point,melt heat,thermal expansion coefficient,point defects,and low-index surface energies ofα-Hf were calculated through molecular dynamics simulations.Comparing with experiment observations from others,it is shown that these properties can be reproduced reasonably by the present model,some results being more consistent to the experimental data than those by previous suggested models.This indicates that this work is sutiable in TB-SMA potential for hexagonal close packed metals. 展开更多
关键词 二阶矩 结合方案 多体 模型理论 实验数据 空位形成能 结构稳定性
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