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Thermodynamic Functions and Phase Transformation of Metal Nanocrystals 被引量:2
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作者 Jinping GAO, Xiaoyan SONG , Jiuxing ZHANG, Keyong YANG and Xuemei LIUCollege of Materials Science and Engineering, the Key Laboratory of Advanced Functional Materials of the Education Ministry,Beijing University of Technology, Beijing 100022, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第5期705-709,共5页
A model to calculate the thermodynamic functions of the pure metal nanocrystals has been developed, with the consideration of the effects of both the interfaces and the crystal in the nano-grain interior. As an exampl... A model to calculate the thermodynamic functions of the pure metal nanocrystals has been developed, with the consideration of the effects of both the interfaces and the crystal in the nano-grain interior. As an example, the enthalpy, entropy and Gibbs free energy, as functions of the excess free volume at interfaces, temperature and grain size, are calculated for the Co nanocrystals. Furthermore, the characteristics of β-Co→α-Co phase transformation are studied, and the transformation temperatures at different levels of grain size, as well as the critical grain sizes at different temperatures, are predicted. The calculation results show that, the nano-grained β-Co (fcc) is thermodynamically stable at temperatures much lower than that for the conventional coarse-grained materials, and may also stably exist at room temperature when the grain size is reduced to be small enough. The present model is verified by comparisons between the experimental findings and the theoretical predictions. 展开更多
关键词 thermodynamic function Nanocrystal Phase transformation
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The transformation of China's economic and government functions
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作者 ZHOU Yu-feng 《Chinese Business Review》 2010年第2期56-60,共5页
The content of China's economic transformation is not single, and this article argues that it includes three parts. The first is the reform of economic system, the second is the change in the pattern of economic grow... The content of China's economic transformation is not single, and this article argues that it includes three parts. The first is the reform of economic system, the second is the change in the pattern of economic growth, and the third is the adjustment of economic structure. Government is the leading force of China's economic transformation, and repeated reform of government institutions has brought about some changes to government functions. But problems are obvious that lag changes of government functions have become an obstacle in China's economic transformation. This article describes the historical evolution and the reality of China's economic transformation, and analyzes the main reasons of lag changes in government functions, and reveals that the transformation of government functions is the key for successful transformation of China's economy. 展开更多
关键词 transformation China's economy government functions
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Zeta Functions of the Complement and xyz-Transformations of a Regular Graph
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作者 WANG Xueqin DENG Aiping 《Journal of Donghua University(English Edition)》 EI CAS 2018年第6期480-485,共6页
Let Z(λ,G)denote the zeta function of a graph G.In this paper the complement G^Cand the G^(xyz)-transformation G^(xyz)of an r-regular graph G with n vertices and m edges for x,y,z∈{0,1,+,-},are considerd.The relatio... Let Z(λ,G)denote the zeta function of a graph G.In this paper the complement G^Cand the G^(xyz)-transformation G^(xyz)of an r-regular graph G with n vertices and m edges for x,y,z∈{0,1,+,-},are considerd.The relationship between Z(λ,G)and Z(λ,G^C)is obtained.For all x,y,z∈{0,1,+,-},the explicit formulas for the reciprocal of Z(λ,G^(xyz))in terms of r,m,n and the characteristic polynomial of G are obtained.Due to limited space,only the expressions for G^(xyz)with z=0,and xyz∈{0++,+++,1+-}are presented here. 展开更多
关键词 regular graph COMPLEMENT xyz-transformation ZETA function
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Pathological and therapeutic effects of extracellular vesicles in neurological and neurodegenerative diseases 被引量:2
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作者 Paula lzquierdo-Altarejos Victoria Moreno-Manzano Vicente Felipo 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期55-61,共7页
Extracellular vesicles are released by all cell types and contain proteins,microRNAs,mRNAs,and other bioactive molecules.Extracellular vesicles play an important role in intercellular communication and in the modulati... Extracellular vesicles are released by all cell types and contain proteins,microRNAs,mRNAs,and other bioactive molecules.Extracellular vesicles play an important role in intercellular communication and in the modulation of the immune system and neuroinflammation.The cargo of extra cellular vesicles(e.g.,proteins and microRNAs)is altered in pathological situations.Extracellular vesicles contribute to the pathogenesis of many pathologies associated with sustained inflammation and neuroinflammation,including cance r,diabetes,hype rammonemia and hepatic encephalopathy,and other neurological and neurodegenerative diseases.Extracellular vesicles may cross the blood-brain barrier and transfer pathological signals from the periphery to the brain.This contributes to inducing neuroinflammation and cognitive and motor impairment in hyperammonemia and hepatic encephalopathy and in neurodegenerative diseases.The mechanisms involved are beginning to be unde rstood.For example,increased tumor necrosis factor a in extracellular vesicles from plasma of hype rammonemic rats induces neuroinflammation and motor impairment when injected into normal rats.Identifying the mechanisms by which extracellular vesicles contribute to the pathogenesis of these diseases will help to develop new treatments and diagnostic tools for their easy and early detection.In contrast,extra cellular vesicles from mesenchymal stem cells have therapeutic utility in many of the above pathologies,by reducing inflammation and neuroinflammation and improving cognitive and motor function.These extra cellular vesicles recapitulate the beneficial effects of mesenchymal stem cells and have advantages as therapeutic tools:they are less immunoge nic,may not diffe rentiate to malignant cells,cross the blood-brain barrier,and may reach more easily target organs.Extracellular vesicles from mesenchymal stem cells have beneficial effects in models of ischemic brain injury,Alzheimer's and Parkinson's diseases,hyperammonemia,and hepatic encephalopathy.Extracellular vesicles from mesenchymal stem cells modulate the immune system,promoting the shift from a pro-inflammato ry to an anti-inflammatory state.For example,extracellular vesicles from mesenchymal stem cells modulate the Th17/Treg balance,promoting the anti-inflammatory Treg.Extracellular vesicles from mesenchymal stem cells may also act directly in the brain to modulate microglia activation,promoting a shift from a pro-inflammatory to an anti-inflammatory state.This reduces neuroinflammation and improves cognitive and motor function.Two main components of extracellular vesicles from mesenchymal stem cells which contribute to these beneficial effects are transforming growth factor-βand miR-124.Identifying the mechanisms by which extracellular vesicles from mesenchymal stem cells induce the beneficial effects and the main molecules(e.g.,proteins and mRNAs)involved may help to improve their therapeutic utility.The aims of this review are to summarize the knowledge of the pathological effects of extracellular vesicles in different pathologies,the therapeutic potential of extra cellular vesicles from mesenchymal stem cells to recover cognitive and motor function and the molecular mechanisms for these beneficial effects on neurological function. 展开更多
关键词 extracellular vesicles INFLAMMATION cognitive function mesenchymal stem cells neurodegenerative diseases NEUROINFLAMMATION theRAPY transforming growth factor-β
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The Similarity Transformation of Regularizing Functionals and Simularity Property of Their Fourier Transformations
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作者 祝同江 《Journal of Beijing Institute of Technology》 EI CAS 1995年第2期105+99-105,共8页
Let and denote respectively the functionswhere λ≥1, The author discusses the similarity transformation of the regularizing functionals of these functions and the similar property of their Fourier transformation.
关键词 Fourier transform generalized functions/similarity transformation regularizing functionals
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Development of a rapid and efficient system for CR genes identification based on hairy root transformation in Brassicaceae
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作者 Wenlin Yu Lu Yang +12 位作者 Yuanyuan Xiang Rongde Li Xueqing Zhou Longcai Gan Xianyu Xiang Yunyun Zhang Lei Yuan Yanqing Luo Genze Li Youning Wang Yinhua Chen Peng Chen Chunyu Zhang 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第4期1049-1060,共12页
Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars bas... Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars based on mapping and cloning of resistant genes is commonly regarded as the most cost-effective and efficient way to fight against this disease.The traditional way of R gene functional validation requires stable transformation that is both time-and labor-consuming.In this study,a rapid and efficient hairy-root transgenic protocol mediated by Agrobacterium rhizogenes was developed.The transformation positive rate was over 80%in Brassica napus showed by GUS reporter gene and this transformation only took 1/6 of the time compared with stable transformation.The system was applicable to different B.napus varieties and other cruciferous crops including Brassica rapa and Brassica oleracea.In particular,two known CR genes,CRA3.7.1 and CRA8.2.4 were used respectively,as example to show that the system works well for CR gene study combined with subsequent P.brassicae infection in B.napus.Most importantly,it works both in over-expression that led to disease resistance,as well as in RNAi which led to disease susceptible phenotype.Therefore,this system can be used in batch-wise identification of CR genes,and also offered the possibility of manipulating key genes within the P.brassicae genome that could improve our knowledge on host-pathogen interaction. 展开更多
关键词 Brassicaceae Agrobacterium rhizogenes Hairy root transformation CLUBROOT Gene function
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Associations between residence and cognitive function among Chinese older adults: the mediating role of leisure activity
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作者 Xiao-Dong Leng Wen-Ping Zeng Mao-Rui Qian 《Medical Data Mining》 2024年第3期46-52,共7页
Background:Cognitive function is a current research hotspot,residence may be related to differences in cognitive function,and the mediating role of leisure activities are limited in Chinese research.This study used le... Background:Cognitive function is a current research hotspot,residence may be related to differences in cognitive function,and the mediating role of leisure activities are limited in Chinese research.This study used leisure activities as a mediating variable to investigate the mediating role of leisure activity between place of residence(city-town-rural)and cognitive function among Chinese older,this is where the innovation of the article comes in.Methods:Using cross-sectional data from the 2018 Chinese Longitudinal Healthy Longevity Survey,Pearson correlation analyses were employed to examine the relationships among various indicators.Mediation analyses were conducted using the SPSS PROCESS macro program,version 3.5,written by Hayes,to explore the mediating effects of leisure activity between place of residence and cognitive function in older adults.Results:A total of 10955 older adults were included in this study,with a mean age of(84.23±11.57)years.Among them,2739(24.8%)lived in the city,3627(33.1%)in town,and 4615(42.1%)in rural areas;their leisure activity score was(5.34±3.77),and their cognitive function score was(24.69±6.65).Place of residence,leisure activities,and cognitive function were significantly correlated(P<0.01).Using city as a reference,place of residence is negatively associated with cognitive function,and place of residence not only had a direct effect on cognitive function in older adults:town-cognitive function(effect=–0.399;95%confidence interval(CI)=(–0.685,–0.113));rural-cognitive function(effect=–0.42;95%CI=(–0.698,–0.141)).There were also indirect effects on cognitive function through the pathway of leisure activity:town-leisure activity-cognitive function(effect=–0.17;95%CI=(–0.246,–0.1)),rural-leisure activity-cognitive function(effect=–0.199;95%CI=(–0.272,–0.13)).Conclusion:Leisure activities play a partially mediating role between the impact of place of residence and cognitive function in Chinese older adults,and it is vital to pay attention to the impact of place of residence on the cognitive function of older adults in various aspects,and to increase the participation rate of older adults in leisure activities,which is beneficial to the prevention of cognitive decline and the protection of older adult’s physical and mental health. 展开更多
关键词 RESIDENCE leisure activity cognitive function intermediary role older adults
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Roles and Functions of Tourism Destinations in Tourism Region of South Anhui:A Tourist Flow Network Perspective 被引量:9
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作者 LIU Fajian ZHANG Jinhe +3 位作者 ZHANG Jie CHEN Dongdong LIU Zehua LU Song 《Chinese Geographical Science》 SCIE CSCD 2012年第6期755-764,共10页
Theoretic and practical significance has been highlighted in the research of the roles and functions of destinations,as destinations are restricted by the spatial structure based on tourist flow network from the persp... Theoretic and practical significance has been highlighted in the research of the roles and functions of destinations,as destinations are restricted by the spatial structure based on tourist flow network from the perspective of relationship.This article conducted an empirical analysis for Tourism Region of South Anhui(TRSA) and revealed the necessity and feasibility of studying the roles and functions of destinations from tourist flow network's perspective.The automorphic equivalence analysis and centrality analysis were used to classify 16 destinations in TRSA into six role types:tourist flow distribution center,hub of tourist flows,passageway destination,common touring destination,attached touring destination,and nearly isolated destination.Some suggestions were given on suitable infrastructure construction and destinations service designs according to their functions in network.This destination role positioning was based on tourist flow network structure in integral and macroscopic way.It provided an important reference for the balanced and harmonious development of all the destinations of TRSA.In addition,this article verified the applicability of social network analysis on tourist flow research in local scale,and expanded this method to destination role and function positioning. 展开更多
关键词 tourist flow network equivalence model roles functions centrality analysis Tourism Region of South Anhui
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Comprehensive Reliability Allocation Method for CNC Lathes Based on Cubic Transformed Functions of Failure Mode and Effects Analysis 被引量:8
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作者 YANG Zhou ZHU Yunpeng +1 位作者 REN Hongrui ZHANG Yimin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第2期315-324,共10页
Reliability allocation of computerized numerical controlled(CNC)lathes is very important in industry.Traditional allocation methods only focus on high-failure rate components rather than moderate failure rate compon... Reliability allocation of computerized numerical controlled(CNC)lathes is very important in industry.Traditional allocation methods only focus on high-failure rate components rather than moderate failure rate components,which is not applicable in some conditions.Aiming at solving the problem of CNC lathes reliability allocating,a comprehensive reliability allocation method based on cubic transformed functions of failure modes and effects analysis(FMEA)is presented.Firstly,conventional reliability allocation methods are introduced.Then the limitations of direct combination of comprehensive allocation method with the exponential transformed FMEA method are investigated.Subsequently,a cubic transformed function is established in order to overcome these limitations.Properties of the new transformed functions are discussed by considering the failure severity and the failure occurrence.Designers can choose appropriate transform amplitudes according to their requirements.Finally,a CNC lathe and a spindle system are used as an example to verify the new allocation method.Seven criteria are considered to compare the results of the new method with traditional methods.The allocation results indicate that the new method is more flexible than traditional methods.By employing the new cubic transformed function,the method covers a wider range of problems in CNC reliability allocation without losing the advantages of traditional methods. 展开更多
关键词 CNC lathes reliability failure modes and effects analysis(FMEA) cubic transformed function comprehensive allocation
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Sine Transformation and the Reparametrization of Bézier Curves 被引量:1
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作者 LIANG Xi-kun TAO Li-min 《Computer Aided Drafting,Design and Manufacturing》 2007年第2期23-27,共5页
A solution to the reparametrization of Bézier curves by sine transformation of Bemstein basis is presented. The new effective reparametrization method is given through the following procedures: educing Sine Bems... A solution to the reparametrization of Bézier curves by sine transformation of Bemstein basis is presented. The new effective reparametrization method is given through the following procedures: educing Sine Bemstein-Bézier Class-SBBC function, defining SBBC curve and discussing the relation between SBBC and Bézier curve. 展开更多
关键词 sine transformation SBBC functions SBBC curves Bézier curve repararnetrization
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Differential Sandwich Theorems for Analytic Functions Defined by an Extended Multiplier Transformation
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作者 Amnah Shammaky 《Advances in Pure Mathematics》 2012年第5期323-329,共7页
In this investigation, we obtain some applications of first order differential subordination and superordination results involving an extended multiplier transformation and other linear operators for certain normalize... In this investigation, we obtain some applications of first order differential subordination and superordination results involving an extended multiplier transformation and other linear operators for certain normalized analytic functions. Some of our results improve previous results. 展开更多
关键词 DIFFERENTIAL SandWICH theOREMS Analytic functions MULTIPLIER transformation
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Inclusion and Argument Properties for Certain Subclasses of Analytic Functions Defined by Using on Extended Multiplier Transformations
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作者 Oh Sang Kwon 《Advances in Pure Mathematics》 2011年第4期193-200,共8页
Making use of a multiplier transformation, which is defined by means of the Hadamard product (or convolution), we introduce some new subclasses of analytic functions and investigate their inclusion relationships and a... Making use of a multiplier transformation, which is defined by means of the Hadamard product (or convolution), we introduce some new subclasses of analytic functions and investigate their inclusion relationships and argument properties. 展开更多
关键词 SUBORDINATION STARLIKE functions CONVEX functions Closed-to-Convex functions MULTIPLIER transformation Multivalent functions ARGUMENT Principle
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The Class of Atomic Exponential Basis Functions EFup_(n)(x,ω)-Development and Application
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作者 Nives Brajcic Kurbasa Blaz Gotovac Vedrana Kozulic 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期65-90,共26页
The purpose of this paper is to present the class of atomic basis functions(ABFs)which are of exponential type and are denoted by EFupn(x,ω).While ABFs of the algebraic type are already represented in the numerical m... The purpose of this paper is to present the class of atomic basis functions(ABFs)which are of exponential type and are denoted by EFupn(x,ω).While ABFs of the algebraic type are already represented in the numerical modeling of various problems inmathematical physics and computationalmechanics,ABFs of the exponential type have not yet been sufficiently researched.These functions,unlike the ABFs of the algebraic type Fupn(x),contain the tension parameterω,which gives them additional approximation properties.Exponential monomials up to the nth degree can be described exactly by the linear combination of the functions EFupn(x,ω).The function EFupn for n=0 is called the“mother”ABF of the exponential type,i.e.,EFup0(x,ω)≡Eup(x,ω).In other words,the functions EFupn(x,ω)are elements of the linear vector space EUPn and retain all the properties of their“mother”function Eup(x,ω).Thus,this paper,in terms of its content and purpose,can be understood as a sequel of the article by Brajcic Kurbasa et al.,which shows the basic properties and application of the basis function Eup(x,ω).This paper presents,in an analogous way,the development and application of the exponential basis functions EFupn(x,ω).Here,for the first time,expressions for calculating the values of the functions EFupn(x,ω)and their derivatives are given in a form suitable for application in numerical analyses,which is shown in the verification examples of the approximations of known functions. 展开更多
关键词 Exponential atomic basis functions Fourier transform compact support tension parameter
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The Dual Functionals for the Generalized Ball Basis of Wang-Said Type and Basis Transformation Formulas 被引量:2
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作者 Ping Jiang Hongyi Wu Jieqing Tan 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第3期248-256,共9页
The generalized Ball curves of Wang-Said type with a position parameter L not only unify the Wang-Ball curves and the Said-Ball curves, but also include several useful intermediate curves. This paper presents the dual... The generalized Ball curves of Wang-Said type with a position parameter L not only unify the Wang-Ball curves and the Said-Ball curves, but also include several useful intermediate curves. This paper presents the dual functionals for the generalized Ball basis of Wang-Said type. The relevant basis transformation formulae are also worked out. 展开更多
关键词 双功能 基本变形 算法 Wang-Said型 伯恩斯坦原理
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Evaluation of the Functional Roles of Cav1.3 (α1D) Calcium Channel in Mouse Atrial and SA Node Cells
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作者 Nipavan CHIAMVIMONVAT 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2005年第S1期45-46,共2页
关键词 Calcium Channel in Mouse Atrial and SA Node Cells NODE Evaluation of the Functional roles of Cav1.3 SA
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The Transformation of Newly Compiled Chinese Genealogical Functions in the New Era
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作者 WANG He-ming HE Jun 《Journal of Literature and Art Studies》 2019年第10期1065-1071,共7页
The cultural customs of compiling genealogy for 5,000 years are an integral part of the Chinese civilization.During the new socialist era,compiling new genealogy is a continuation and development of old genealogy,a cu... The cultural customs of compiling genealogy for 5,000 years are an integral part of the Chinese civilization.During the new socialist era,compiling new genealogy is a continuation and development of old genealogy,a cultural phenomenon adapting to social and public needs.The paper examines how Chinese genealogies transformed,and then explores how new genealogies have the new cultural function of serving the socialist era.The paper concludes with comments on how new compilations play a positive role in the construction of a harmonious society. 展开更多
关键词 new GENEALOGY CULTURAL function transformation
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An Overview of Government-Market Relationships:Evolving Perceptions,Role of the Market,and Government Functions
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作者 Li Xiang Tang Yong 《Contemporary Social Sciences》 2023年第3期65-84,共20页
Building a high-level socialist market economy is conducive to giving full play to the market’s decisive role in resource allocations and bringing the government into better play.Correctly handling the market and the... Building a high-level socialist market economy is conducive to giving full play to the market’s decisive role in resource allocations and bringing the government into better play.Correctly handling the market and the government relationships has been a central issue in China’s economic structural reform.Giving a comprehensive review and summary of the research findings achieved by the theoretical and academic circles in China,we generalize the evolution and working mechanisms of China’s socialist market economy system,following the developing trajectory and logic of relevant literature,focusing on the three aspects of evolving perceptions,the role of the market,and the functions of the government.Based on our literature overview,we also induced and extracted the basic conclusions and evolutionary features of relevant research and made suggestions for the future direction of theoretical research regarding China’s socialist market economy. 展开更多
关键词 socialist market economy system evolving perceptions the role of the market government functions
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The filtering characteristics of HHT and its application in acoustic log waveform signal processing 被引量:5
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作者 王祝文 刘菁华 +2 位作者 岳崇旺 李晓春 李长春 《Applied Geophysics》 SCIE CSCD 2009年第1期8-16,102,共10页
Array acoustic logging plays an important role in formation evaluation. Its data is a non-linear and non-stationary signal and array acoustic logging signals have time-varying spectrum characteristics. Traditional fil... Array acoustic logging plays an important role in formation evaluation. Its data is a non-linear and non-stationary signal and array acoustic logging signals have time-varying spectrum characteristics. Traditional filtering methods are inadequate. We introduce a Hilbert- Huang transform (HHT) which makes full preservation of the non-linear and non-stationary characteristics and has great advantages in the acoustic signal filtering. Using the empirical mode decomposition (EMD) method, the acoustic log waveforms can be decomposed into a finite and often small number of intrinsic mode functions (IMF). The results of applying HHT to real array acoustic logging signal filtering and de-noising are presented to illustrate the efficiency and power of this new method. 展开更多
关键词 Hilbert-Huang transform empirical mode decomposition intrinsic mode functions time-frequency filter
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REFINEMENTS OF TRANSFORMATION INEQUALITIES FOR ZERO-BALANCED HYPERGEOMETRIC FUNCTIONS 被引量:9
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作者 王淼坤 褚玉明 《Acta Mathematica Scientia》 SCIE CSCD 2017年第3期607-622,共16页
In the article, we present some refinements of three classes of transformation inequalities for zero-balanced hypergeometric functions by use of the updated monotonicity criterion for the quotient of power series.
关键词 Gauss hypergeometric function complete elliptic integrals quadratic transfor-mation Ramanujan cubic transformation
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Changes in Transformation of Soil Organic C and Functional Diversity of Soil Microbial Community Under Different Land Uses 被引量:22
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作者 LI Zhong-pei WU Xiao-chen CHEN Bi-yun 《Agricultural Sciences in China》 CAS CSCD 2007年第10期1235-1245,共11页
Changes in soil biological and biochemical properties under different land uses in the subtropical region of China were investigated in order to develop rational cultivation and fertilization management. A small water... Changes in soil biological and biochemical properties under different land uses in the subtropical region of China were investigated in order to develop rational cultivation and fertilization management. A small watershed of subtropical region of China was selected for this study. Land uses covered paddy fields, vegetable farming, fruit trees, upland crops, bamboo stands, and forestry. Soil biological and biochemical properties included soil organic C and nutrient contents, mineralization of soil organic C, and soil microbial biomass and community functional diversity. Soil organic C and total N contents, microbial biomass C and N, and respiration intensity under different land uses were changed in the following order: paddy fields (and vegetable farming) 〉 bamboo stands 〉 fruit trccs (and upland). The top surface (0-15 cm) paddy fields (and vegetable farming) were 76.4 and 80.8% higher in soil organic C and total N contents than fruit trees (and upland) soils, respectively. Subsurface paddy soils (15-30 cm) were 59.8 and 67.3% higher in organic C and total N than upland soils, respectively. Soil microbial C, N and respiration intensity in paddy soils (0-15 cm) were 6.36, 3.63 and 3.20 times those in fruit tree (and upland) soils respectively. Soil microbial metabolic quotient was in the order: fruit trees (and upland) 〉 forestry 〉 paddy fields. Metabolic quotient in paddy soils was only 47.7% of that in fruit tree (and upland) soils. Rates of soil organic C mineralization during incubation changed in the order: paddy fields 〉 bamboo stands 〉 fruit trees (and upland) and soil bacteria population: paddy fields 〉 fruit trees (and upland) 〉 forestry. No significant difference was found for fungi and actinomycetes populations. BIOLOG analysis indicated a changing order of paddy fields 〉 fruit trees (and upland) 〉 forestry in values of the average well cell development (AWCD) and functional diversity indexes of microbial community. Results also showed that the conversion from paddy fields to vegetable farming for 5 years resulted in a dramatic increase in soil available phosphorus content while insignificant changes in soil organic C and total N content due to a large inputs of phosphate fertilizers. This conversion caused 53, 41.5, and 41.3% decreases in soil microbial biomass C, N, and respiration intensity, respectively, while 23.6% increase in metabolic quotient and a decrease in soil organic C mineralization rate. Moreover, soil bacteria and actinomycetes populations were increased slightly, while fungi population increased dramatically. Functional diversity indexes of soil microbial community decreased significantly. It was concluded that land uses in the subtropical region of China strongly affected soil biological and biochemical properties. Soil organic C and nutrient contents, mineralization of organic C and functional diversity of microbial community in paddy fields were higher than those in upland and forestry. Overuse of chemical fertilizers in paddy fields with high fertility might degrade soil biological properties and biochemical function, resulting in deterioration of soil biological quality. 展开更多
关键词 land use patterns transformation of soil organic carbon functional diversity of soil microbial community
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