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Calculation and prediction of divertor detachment via impurity seeding by using one-dimensional model
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作者 周文杰 刘晓菊 +5 位作者 邬潇河 李邦 石奇奇 樊皓尘 杨艳杰 李国强 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期370-379,共10页
Achieving the detachment of divertor can help to alleviate excessive heat load and sputtering problems on the target plates,thereby extending the lifetime of divertor components for fusion devices.In order to provide ... Achieving the detachment of divertor can help to alleviate excessive heat load and sputtering problems on the target plates,thereby extending the lifetime of divertor components for fusion devices.In order to provide a fast but relatively reliable prediction of plasma parameters along the flux tube for future device design,a one-dimensional(1D)modeling code for the operating point of impurity seeded detached divertor is developed based on Python language,which is a fluid model based on previous work(Plasma Phys.Control.Fusion 58045013(2016)).The experimental observation of the onset of divertor detachment by neon(Ne)and argon(Ar)seeding in EAST is well reproduced by using the 1D modeling code.The comparison between the 1D modeling and two-dimensional(2D)simulation by the SOLPS-ITER code for CFETR detachment operation with Ne and Ar seeding also shows that they are in good agreement.We also predict the radiative power loss and corresponding impurity concentration requirement for achieving divertor detachment via different impurity seeding under high heating power conditions in EAST and CFETR phase II by using the 1D model.Based on the predictions,the optimized parameter space for divertor detachment operation on EAST and CFETR is also determined.Such a simple but reliable 1D model can provide a reasonable parameter input for a detailed and accurate analysis by 2D or three-dimensional(3D)modeling tools through rapid parameter scanning. 展开更多
关键词 divertor detachment impurity seeding one-dimensional modeling
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A luminescent one-dimensional covalent organic framework for organic arsenic sensing in water
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作者 Chao Liu Chao Jia +3 位作者 Shi-Xian Gan Qiao-Yan Qi Guo-Fang Jiang Xin Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第11期304-308,共5页
Roxarsone(ROX)is a commonly used antibacterial and growth-promoting additive to animal feed.The development of an effective method for detecting ROX and its conversion products is of importance because of their potent... Roxarsone(ROX)is a commonly used antibacterial and growth-promoting additive to animal feed.The development of an effective method for detecting ROX and its conversion products is of importance because of their potential harm to human health and ecosystem.Herein,we report the designed synthesis of a novel one-dimensional covalent organic framework(1D COF),named EP-COF,and its application as a fluorescent probe for ROX sensing.EP-COF is constructed based on imine linkages,exhibiting high crystallinity,strong fluorescence emission,and good dispersibility in water.It displays a remarkable capability to efficiently detect ROX,with an impressive detection limit of 4.5 nmol/L.Moreover,EP-COF also offers advantages of excellent selectivity,and high structural stability.This work not only presents a promising approach for the detection of harmful substances like ROX,but also serves as a valuable reference for exploring application of 1D COFs in chemical sensing. 展开更多
关键词 one-dimensional Covalent organic framework Fluorescent probe ROXARSONE SENSING
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Numerical Investigations on the Resonance Errors of Multiscale Discontinuous Galerkin Methods for One-Dimensional Stationary Schrödinger Equation
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作者 Bo Dong Wei Wang 《Communications on Applied Mathematics and Computation》 EI 2024年第1期311-324,共14页
In this paper,numerical experiments are carried out to investigate the impact of penalty parameters in the numerical traces on the resonance errors of high-order multiscale discontinuous Galerkin(DG)methods(Dong et al... In this paper,numerical experiments are carried out to investigate the impact of penalty parameters in the numerical traces on the resonance errors of high-order multiscale discontinuous Galerkin(DG)methods(Dong et al.in J Sci Comput 66:321–345,2016;Dong and Wang in J Comput Appl Math 380:1–11,2020)for a one-dimensional stationary Schrödinger equation.Previous work showed that penalty parameters were required to be positive in error analysis,but the methods with zero penalty parameters worked fine in numerical simulations on coarse meshes.In this work,by performing extensive numerical experiments,we discover that zero penalty parameters lead to resonance errors in the multiscale DG methods,and taking positive penalty parameters can effectively reduce resonance errors and make the matrix in the global linear system have better condition numbers. 展开更多
关键词 Discontinuous Galerkin(DG)method Multiscale method Resonance errors one-dimensional Schrödinger equation
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Parental Psychological Control and Internet Gaming Disorder Tendency:A Moderated Mediation Model of Core Self-Evaluation and Intentional Self-Regulation
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作者 Zhiqiao Ji Shuhua Wei Hejuan Ding 《International Journal of Mental Health Promotion》 2024年第7期547-558,共12页
Internet gaming disorder(IGD)among junior high school students is an increasingly prominent mental health concern.It is important to look for influences behind internet gaming disorder tendency(IGDT)in the junior high... Internet gaming disorder(IGD)among junior high school students is an increasingly prominent mental health concern.It is important to look for influences behind internet gaming disorder tendency(IGDT)in the junior high school student population.The present study aimed to reveal the explanatory mechanisms underlying the association between parental psychological control(PPC)and internet gaming disorder tendency among junior high school students by testing the mediating role of core self-evaluation(CSE)and the moderating role of intentional self-regulation(ISR).Participants in present study were 735 Chinese junior high school students who completed offline self-report questionnaires on parental psychological control,core self-evaluation,intentional self-regulation,and Internet gaming disorder tendency.Analyses were conducted via mediation and moderated mediation.The results showed that:(1)Parental psychological control was positively related to junior high school students’Internet gaming disorder tendency.Core self-evaluation,and intentional self-regulation were negatively related to junior high school students’Internet gaming disorder tendency,respectively.(2)Core self-evaluation partially mediated the relationship between parental psychological control and junior high school students’Internet gaming disorder tendency.(3)Intentional self-regulation moderated the association between parental psychological control and Internet gaming disorder tendency,as well as the relationships between parental psychological control and core self-evaluation and core self-evaluation and Internet gaming disorder tendency in the mediated model.Based on these findings,we believe that there is a need to weaken parental psychological control,strengthen junior high school students’core self-evaluation and intentional self-regulation,and to recognize the important role of parents as well as their children’s personal positive traits in the healthy development of junior high school students. 展开更多
关键词 Internet gaming disorder tendency parental psychological control core self-evaluation intentional self-regulation moderated mediation model junior high school students
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Prediction of one-dimensional CrN nanostructure as a promising ferromagnetic half-metal
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作者 相文雨 王亚萍 +3 位作者 纪维霄 侯文杰 李胜世 王培吉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期429-435,共7页
Searching for one-dimensional(1D)nanostructure with ferromagnetic(FM)half-metallicity is of significance for the development of miniature spintronic devices.Here,based on the first-principles calculations,we propose t... Searching for one-dimensional(1D)nanostructure with ferromagnetic(FM)half-metallicity is of significance for the development of miniature spintronic devices.Here,based on the first-principles calculations,we propose that the 1D CrN nanostructure is a FM half-metal,which can generate the fully spin-polarized current.The ab initio molecular dynamic simulation and the phonon spectrum calculation demonstrate that the 1D CrN nanostructure is thermodynamically stable.The partially occupied Cr-d orbitals endow the nanostructure with FM half-metallicity,in which the half-metallic gap(?s)reaches up to 1.58 eV.The ferromagnetism in the nanostructure is attributed to the superexchange interaction between the magnetic Cr atoms,and a sizable magnetocrystalline anisotropy energy(MAE)is obtained.Moreover,the transverse stretching of nanostructure can effectively modulate?s and MAE,accompanied by the preservation of half-metallicity.A nanocable is designed by encapsulating the CrN nanostructure with a BN nanotube,and the intriguing magnetic and electronic properties of the nanostructure are retained.These novel characteristics render the 1D CrN nanostructure as a compelling candidate for exploiting high-performance spintronic devices. 展开更多
关键词 HALF-METAL FERROMAGNETISM one-dimensional nanostructure first-principles calculations
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Paleostress Reconstruction from 3D Seismic Data and Slip Tendency in the Northern Slope Area of the Bongor Basin, Southwestern Chad
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作者 Hakro Ahmed Suhail Xintao Yuan +3 位作者 Jianlin Li Hong Liu Yuan Liu Cong Ma 《Open Journal of Geology》 CAS 2023年第5期536-578,共43页
Paleostress plays a significant role in controlling the formation, accumulation, and distribution of reservoirs, and this could be an important factor in controlling the production of hydrocarbons from the unconventio... Paleostress plays a significant role in controlling the formation, accumulation, and distribution of reservoirs, and this could be an important factor in controlling the production of hydrocarbons from the unconventional reservoirs. In this study, we will use 3D seismic reflection data to perform the slip-tendency-based stress inversion to determine the stress field in the basement of the northern slope area in the Bongor Basin. The dataset for this technique is easily available in the oil and gas companies. The stress inversion results from the basement of the northern slope area of Bongor basin show that the maximum principal stress axis (σ1) is oriented vertically, the intermediate principal stress axis (σ2) is oriented N18° and the minimum principal stress axis (σ3) is oriented N105°, and σ2/σ1 = 0.60 and σ3/σ1 = 0.29. The findings of this paper provide significant information to understand the fault reactivation at the critical stage of hydrocarbon accumulation and the regional tectonic evolution. 展开更多
关键词 Seismic Reflection Data Slip tendency Bongor Basin Stress Inversion
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The Effect of Self-Investment on Hoarding Tendency of Chinese College Students:Role of Psychological Connections
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作者 Xiangli Guan Yue Zhang +6 位作者 Yang Li Yaqi Zhang Jingjing Wang Xuejiao Li Mary C.Jobe Md Zahir Ahmed Oli Ahmed 《International Journal of Mental Health Promotion》 2023年第6期755-766,共12页
Because of factors such as energy and time one invests in an object,the stronger the connection,value,and reluc-tance to lose said object individual will have.Hoarding behavior arises when individuals incorporate a st... Because of factors such as energy and time one invests in an object,the stronger the connection,value,and reluc-tance to lose said object individual will have.Hoarding behavior arises when individuals incorporate a strong attachment with themselves to an object.The purpose of this study is to examine the effect of self-investment on hoarding tendency and the roles of possession-self link and liking level in this connection.A hypothetical model of the relationship between self-investment,possession-self link,liking level,and hoarding tendency was tested.A convenience sampling method was used to survey 450 college students in Yunnan Province on either a paper-based or online self-report scale.The data were collected using self-investment,possession-self link,and liking level questionnaires,as well as the Saving Inventory Revised.Results showed positive relationship between the study variables,ranging from 0.37 to 0.87.College students’self-investment had a direct positive pre-dictive effect on hoarding tendency;self-investment,in turn,indirectly predicted hoarding tendency through the mediating effect of possession-self link;and individual liking level of items had a moderating effect for self-invest-ment on the possession-self link.This study shows how self-investment affects the hoarding tendency of college students,and the results of this study also help demonstrate the value of self-investment and possession-self link in optimizing students’hoarding tendency and thus promoting good psychological status. 展开更多
关键词 Hoarding tendency self-investment psychological connections possession-self link liking level
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Construction of Psychological Adjustment Function Model of Music Education Based on Emotional Tendency Analysis
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作者 Bin Zhang 《International Journal of Mental Health Promotion》 2023年第5期655-671,共17页
In the face offierce competition in the social environment,mental health problems gradually get the attention of the public,in order to achieve accurate mental health data analysis,the construction of music education ... In the face offierce competition in the social environment,mental health problems gradually get the attention of the public,in order to achieve accurate mental health data analysis,the construction of music education is based on emotional tendency analysis of psychological adjustment function model.Design emotional tendency analysis of music education psychological adjustment function architecture,music teaching goal as psychological adjust-ment function architecture building orientation,music teaching content as a foundation for psychological adjust-ment function architecture and music teaching process as a psychological adjustment function architecture building,music teaching evaluation as the key of building key regulating function architecture,Establish a core literacy oriented evaluation system.Different evaluation methods were used to obtain the evaluation results.Four levels of psychological adjustment function model of music education are designed,and the psychological adjust-ment function of music education is put forward,thus completing the construction of psychological adjustment function model of music education.The experimental results show that the absolute value of the data acquisition error of the designed model is minimum,which is not more than 0.2.It is less affected by a bad coefficient and has good performance.It can quickly converge to the best state in the actual prediction process and has a strong con-vergence ability. 展开更多
关键词 Emotional tendency analysis music education psychological adjustment functional model core literacy orientation
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Size effect on light propagation modulation near band edges in one-dimensional periodic structures
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作者 唐洋 王佳俊 +2 位作者 赵星棋 李同宇 石磊 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期421-424,共4页
Periodic photonic structures can provide rich modulation in propagation of light due to well-defined band structures.Especially near band edges,light localization and the effect of near-zero refractive index have attr... Periodic photonic structures can provide rich modulation in propagation of light due to well-defined band structures.Especially near band edges,light localization and the effect of near-zero refractive index have attracted wide attention.However,the practically fabricated structures can only have finite size,i.e.,limited numbers of periods,leading to changes of the light propagation modulation compared with infinite structures.Here,we study the size effect on light localization and near-zero refractive-index propagation near band edges in one-dimensional periodic structures.Near edges of the band gap,as the structure's size shrinks,the broadening of the band gap and the weakening of the light localization are discovered.When the size is small,an added layer on the surface will perform large modulation in the group velocity.Near the degenerate point with Dirac-like dispersion,the zero-refractive-index effects like the zero-phase difference and near-unity transmittance retain as the size changes,while absolute group velocity fluctuates when the size shrinks. 展开更多
关键词 one-dimensional(1D)photonic crystal finite-size effect band gap light localization zerorefractive-index effect
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A Dugdale-Barenblatt model for elliptical orifice problem with asymmetric cracks in one-dimensional orthorhombic quasicrystals
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作者 Jing ZHANG Guanting LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第9期1533-1546,共14页
By means of Muskhelishvili’s method and the technique of generalized conformal mapping,the physical plane problems are transformed into regular mathematical problems in quasicrystals(QCs).The analytical solution to a... By means of Muskhelishvili’s method and the technique of generalized conformal mapping,the physical plane problems are transformed into regular mathematical problems in quasicrystals(QCs).The analytical solution to an elliptical orifice problem with asymmetric cracks in one-dimensional(1D)orthorhombic QCs is obtained.By using the Dugdale-Barenblatt model,the plastic simulation at the crack tip of the elliptical orifice with asymmetric cracks in 1D orthorhombic QCs is performed.Finally,the size of the atomic cohesive force zone is determined precisely,and the size of the atomic cohesive force zone around the crack tip of an elliptical orifice with a single crack or two symmetric cracks is obtained. 展开更多
关键词 one-dimensional(1D)orthorhombic quasicrystal(QC) Dugdale-Barenblatt model atomic cohesive force zone crack
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Robust Damage Detection and Localization Under Complex Environmental Conditions Using Singular Value Decomposition-based Feature Extraction and One-dimensional Convolutional Neural Network
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作者 Shengkang Zong Sheng Wang +3 位作者 Zhitao Luo Xinkai Wu Hui Zhang Zhonghua Ni 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期252-261,共10页
Ultrasonic guided wave is an attractive monitoring technique for large-scale structures but is vulnerable to changes in environmental and operational conditions(EOC),which are inevitable in the normal inspection of ci... Ultrasonic guided wave is an attractive monitoring technique for large-scale structures but is vulnerable to changes in environmental and operational conditions(EOC),which are inevitable in the normal inspection of civil and mechanical structures.This paper thus presents a robust guided wave-based method for damage detection and localization under complex environmental conditions by singular value decomposition-based feature extraction and one-dimensional convolutional neural network(1D-CNN).After singular value decomposition-based feature extraction processing,a temporal robust damage index(TRDI)is extracted,and the effect of EOCs is well removed.Hence,even for the signals with a very large temperature-varying range and low signal-to-noise ratios(SNRs),the final damage detection and localization accuracy retain perfect 100%.Verifications are conducted on two different experimental datasets.The first dataset consists of guided wave signals collected from a thin aluminum plate with artificial noises,and the second is a publicly available experimental dataset of guided wave signals acquired on a composite plate with a temperature ranging from 20℃to 60℃.It is demonstrated that the proposed method can detect and localize the damage accurately and rapidly,showing great potential for application in complex and unknown EOC. 展开更多
关键词 Ultrasonic guided waves Singular value decomposition Damage detection and localization Environmental and operational conditions one-dimensional convolutional neural network
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Analysis of Dynamical Behavior of One-Dimensional Real Maps: An Executable Dynamical Programming Software Approach
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作者 Mohammad Sharif Ullah Masuda Akter K. M. Ariful Kabir 《Applied Mathematics》 2023年第9期652-672,共21页
The dynamical behavior of real-world phenomena is implausible graphically due to the complexity of mathematical coding. The present article has mainly focused on some one-dimensional real maps’ dynamical behavior irr... The dynamical behavior of real-world phenomena is implausible graphically due to the complexity of mathematical coding. The present article has mainly focused on some one-dimensional real maps’ dynamical behavior irrespective of using coding. In continuation, linear, quadratic, cubic, higher-order, exponential, logarithmic, and absolute value maps have been used to scrutinize their dynamical behavior, including the characteristics of the orbit of points. Dynamical programming software (DPS.exe) will be proposed as a new technique to ascertain the dynamical behavior of said maps. Thus, a mathematician can automatically determine one-dimensional real maps’ dynamical behavior apart from complicated programming code and analytical solutions. 展开更多
关键词 one-dimensional Map Cobweb Orbit Diagram Fixed Point the Fate of the Orbit
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Thermal-induced interfacial behavior of a thin one-dimensional hexagonal quasicrystal film
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作者 Huayang DANG Dongpei QI +2 位作者 Minghao ZHAO Cuiying FAN C.S.LU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第5期841-856,共16页
In this paper,we investigate the interfacial behavior of a thin one-dimensional(1D)hexagonal quasicrystal(QC)film bonded on an elastic substrate subjected to a mismatch strain due to thermal variation.The contact inte... In this paper,we investigate the interfacial behavior of a thin one-dimensional(1D)hexagonal quasicrystal(QC)film bonded on an elastic substrate subjected to a mismatch strain due to thermal variation.The contact interface is assumed to be nonslipping,with both perfectly bonded and debonded boundary conditions.The Fourier transform technique is adopted to establish the integral equations in terms of interfacial shear stress,which are solved as a linear algebraic system by approximating the unknown phonon interfacial shear stress via the series expansion of the Chebyshev polynomials.The expressions are explicitly obtained for the phonon interfacial shear stress,internal normal stress,and stress intensity factors(SIFs).Finally,based on numerical calculations,we briefly discuss the effects of the material mismatch,the geometry of the QC film,and the debonded length and location on stresses and SIFs. 展开更多
关键词 one-dimensional(1D)hexagonal quasicrystal(QC)film stress intensity factor(SIF) thermal variation Chebyshev polynomial interfacial behavior
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Self-heating tendency evaluation of sulfide ores based on nonlinear multi-parameters fusion 被引量:1
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作者 潘伟 吴超 +1 位作者 李孜军 杨月平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第2期582-589,共8页
In order to reveal the nonlinear dynamics characteristics of unsteady self-heating process of sulfide ores, nine different kinds of sulfide ore samples from a pyrite mine in China were taken as experimental materials ... In order to reveal the nonlinear dynamics characteristics of unsteady self-heating process of sulfide ores, nine different kinds of sulfide ore samples from a pyrite mine in China were taken as experimental materials and their self-heating characteristics were measured in laboratory. Furthermore, the measured temperature was studied by integrating wavelet transform, nonlinear characteristic parameters extraction and fuzzy comprehensive evaluation. The results indicate that only the ore samples 1, 2, 6 and 9 have obvious self-heating phenomenon, and their self-heating initiative temperatures are 220 ℃, 239 ℃, 220 ℃ and 220 ℃, respectively, which means that they are difficult to produce self-heating under normal mining conditions. The correlation dimension of self-heating process is fraction and the maximum Lyapunov exponent is positive, which means that it is feasible to study the self-heating process based on chaotic dynamics theory. The nonlinearities of self-heating process of these four samples (ore samples 1, 2, 6 and 9) are 0.8227, 0.7521, 0.9401 and 0.8827 respectively and the order of the samples according to these results is: sample 6, sample 9, sample 1, sample 2, which is consistent with the measured results of self-heating characteristics. Therefore, the nonlinearity method can be used to evaluate the self-heating tendency of sulfide ores, and it is an effective verification of the reliability of measured results. 展开更多
关键词 sulfide ores self-heating process nonlinear characteristic parameter NONLINEARITY self-heating tendency
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The Feminist Tendency in Hotel du Lac
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作者 朱晓静 《海外英语》 2019年第24期225-226,共2页
It is true that some important feminist literary theories apply to Hotel du Lac,which illustrates clearly Brookner’s deep concern over modern women’s predicament in favor of their interests,and thus proves her stron... It is true that some important feminist literary theories apply to Hotel du Lac,which illustrates clearly Brookner’s deep concern over modern women’s predicament in favor of their interests,and thus proves her strong tendency to feminism.And then it is pointed out that the reason for Brookner’s perverse attitude toward feminism mainly lies in her unwillingness to confine herself to the category of feminism and actually Brookner has transcended the more stereotypical feminism. 展开更多
关键词 FEMINIST tendency TRANSCENDENCE
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A Study of Romantic Tendency in Jane Austen's works——A Comparison between Sense and Sensibility and Persuasion
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作者 具东梅 《疯狂英语(理论版)》 2017年第4期165-166,共2页
Sense and Sensibility and Persuasion is Jane Austen's first and last published works respectively, which are read widely all over the world. Austen proclaims that feeling should be governed by reason in Sense and ... Sense and Sensibility and Persuasion is Jane Austen's first and last published works respectively, which are read widely all over the world. Austen proclaims that feeling should be governed by reason in Sense and Sensibility and that reason should be compatible with feeling in Persuasion. This paper attempts to explore romantic tendency in Austen's works according to the comparison and contrast between her two novels. Through comparison and contrast, we can see the transformation of Marianne from a lady of sensibility to a sensible lady and the growth of Anne into a lady with romance. 展开更多
关键词 Jane Austen FEELING REASON romantic tendency
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Controlled synthesis of one-dimensional Au-Ag porous nanostructures 被引量:2
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作者 杨立山 谷小虎 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1807-1812,共6页
The fabrication of a new type of one-dimensional Au-Ag porous nanotube(NPT) structure was presented based on a facile combination of nanocrystal growth and surface modification.Ag nanowires with various diameters we... The fabrication of a new type of one-dimensional Au-Ag porous nanotube(NPT) structure was presented based on a facile combination of nanocrystal growth and surface modification.Ag nanowires with various diameters were firstly served as the chemical plating templates via a polyol-process.Then,one-dimensional(1D) Au-Ag porous nanostructures with tailored structural features could be prepared by controlling the individual steps involved in this process,such as nanowire growth,surface modification,thermal diffusion,and dealloying.Structural characterizations reveal these Au-Ag porous nanotubes,non-porous nanotubes and porous nanowires possess novel nano-architectures with multimodal open porosity and excellent structural continuity and integrity,which make them particularly desirable as novel 1D nanocarriers for biomedical,drug delivery and sensing applications. 展开更多
关键词 one-dimension Ag alloy thermal diffusion DEALLOYING porous nanostructure NANOTUBE
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Variation Characteristics and Tendency of Precipitation in Chaoyang Area between 1908 and 2008 被引量:3
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作者 周国华 谭明军 +1 位作者 穆春华 常忠波 《Meteorological and Environmental Research》 CAS 2010年第1期26-29,共4页
According to the precipitation sequence of Beijing City from 1900 to 1958,the precipitation sequence of Chengde City were revised and extended.Then the precipitation sequence of Chaoyang City were revised and extended... According to the precipitation sequence of Beijing City from 1900 to 1958,the precipitation sequence of Chengde City were revised and extended.Then the precipitation sequence of Chaoyang City were revised and extended with the precipitation sequence of Chengde City to form 100-years precipitation sequence of Chaoyang.The results showed that the 100-years precipitation sequence of Chaoyang indicated a decreasing trend and obvious periodic variation with the change of age.That is,a 10-year rainy period (approximately 525.0 mm) appeared every 30 a,while the 30-year drought period was approximately 460.0 mm,65.0 mm lower than the former.Moreover,an obviously heavy drought lasting for 2-4 a appeared every 20 a. 展开更多
关键词 100-years precipitation Sequence revision Periodic variation Characteristics tendency China
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Development Tendency in Main Fields of Reading Researches
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作者 石晶 《中国校外教育》 2011年第9期89-89,106,共2页
The last few decades have witnessed the publication of a considerable amount of empirical evidence supporting what Krashen has called "the power of reading"(Krashen,1993).There is a widespread approval that ... The last few decades have witnessed the publication of a considerable amount of empirical evidence supporting what Krashen has called "the power of reading"(Krashen,1993).There is a widespread approval that reading itself leads to better reading,better vocabulary,better writing,and better control of grammar in both first and second languages.In this article,the following research areas will be discussed,which can be mainly divided into the following 20 categories. 展开更多
关键词 英语教学 教学方法 大学英语 英语翻译
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Sensitivity to Tendency Perturbations of Tropical Cyclone Short-range Intensity Forecasts Generated by WRF 被引量:8
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作者 Xiaohao QIN Wansuo DUAN Hui XU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第3期291-306,共16页
The present study uses the nonlinear singular vector(NFSV)approach to identify the optimally-growing tendency perturbations of the Weather Research and Forecasting(WRF)model for tropical cyclone(TC)intensity forecasts... The present study uses the nonlinear singular vector(NFSV)approach to identify the optimally-growing tendency perturbations of the Weather Research and Forecasting(WRF)model for tropical cyclone(TC)intensity forecasts.For nine selected TC cases,the NFSV-tendency perturbations of the WRF model,including components of potential temperature and/or moisture,are calculated when TC intensities are forecasted with a 24-hour lead time,and their respective potential temperature components are demonstrated to have more impact on the TC intensity forecasts.The perturbations coherently show barotropic structure around the central location of the TCs at the 24-hour lead time,and their dominant energies concentrate in the middle layers of the atmosphere.Moreover,such structures do not depend on TC intensities and subsequent development of the TC.The NFSV-tendency perturbations may indicate that the model uncertainty that is represented by tendency perturbations but associated with the inner-core of TCs,makes larger contributions to the TC intensity forecast uncertainty.Further analysis shows that the TC intensity forecast skill could be greatly improved as preferentially superimposing an appropriate tendency perturbation associated with the sensitivity of NFSVs to correct the model,even if using a WRF with coarse resolution. 展开更多
关键词 sensitivity tendency perturbation tropical cyclone INTENSITY forecasts
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