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Chinese Journal of Chemistry 1994年第5期12卷 425-431页

作者： XIE, Qing-Ji PANG, Xiao-Yong NIE, li-Hua YAO, Shou-Zhuo department of Chemistry and Chemical Engineering, hunan university, changsha, hunan 410082, china department of Chemistry and Chemical Engineering Hunan University Changsha Hunan 410082 China

Piezoelectric transmission spectroelectrochemistry (PTSEC), i.e., the combination of electrochemistry and spectroelectrochemistry (SEC) with electrochemical quartz crystal microbalance (EQCM) technique is reported by using a normal piezoelectric quartz crystal (PQC) as an optically-transparent electrode (OTE). A theoretical relationship between the PQC response and the spectroelectrochemical response is derived and used to estimate the apparent molar absorptivity of the absorbing species deposited on the OTE on the PQC surface. The complex of copper with aspartic acid is used to test this new PQC-SEC technique. Results show that the combination of three such diverse techniques provides a very useful methodology for studying electrode processes and electrode surface characteristics in situ.

关键词： Piezoelectronic transimission spectroelectrochemistry optically-transparent electrode electrochemical quartz crystal microbalance copper aspartic acid.

The Existence of Entropy Solutions to Some Parabolic Problems with L^1 Data

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Acta Mathematica Sinica,English Series 2002年第1期18卷 119-128页

作者： li Feng Quan department of mathematics. Qufu normal university, Shandong 273165. P. R. china department of mathematics Qufu Normal University Shandon P. R. China

In this paper, an existence result of entropy solutions to some parabolic problems is established. The data belongs to L^1 and no growth assumption is made on the lower-order term in divergence form.

关键词： Existence Parabolic problems Entropy solutions L^1 Data

A Sufficient Condition for a Smash Product as a Transfinite Left Free normalizing Extension and Its Application

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Acta Mathematica Sinica,English Series 2000年第1期16卷 71-78页

作者： Fang li department of mathematics,Zhejiang university Xixi Campus,Hangzhou 310028,P.R.chinaZhongkui liu department of mathematics,Northwest normal university,Lanzhou 730070,P.R.china department of mathematics Zhejing University Xixi Campus Hangzhou 310028 P.R. China

In this paper,a sufficient condition is given under which the smash product A#H is a transfinite *** normalizing extension of an algebra ***,the result is applied to a skew semigroup ring,a skew group ring and the qua... 详细信息

关键词： Smash product Transfinite left free normalizing extension Skew semigroup ring Quantum group

Different-Periodic Travelling Wave Solutions for Nonlinear Equations

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Communications in Theoretical Physics 2004年第4期41卷 481-486页

作者： YE li-Jun~1 liN Ji~(1,2)1 department of Physics,Zhejiang normal university,Jinhua 321004,china2 Physics department,Shanghai Jiao Tong university,Shanghai 200030,china Physics department Shanghai Jiao Tong University Shanghai 200030 China

Using Jacobi elliptic function linear superposition approach for the(1+1)-dimensional Caudrey-Dodd-Gibbon-Sawada-Kotera(CDGSK)equation and the(2+1)-dimensional Nizhnik-Novikov-Veselov(NNV)equation,many new periodic travelling wave solutions with different periods and velocities are obtained based on the knownperiodic *** procedure is crucially dependent on a sequence of cyclic identities involving Jacobi ellipticfunctions sn(ξ,m),cn(ξ,m),and dn(ξ,m).

关键词： linear superposition nonlinear equation travelling wave solution

The connectedness of H(λ) unit interval and H(λ) real line

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Chinese Science Bulletin 1997年第23期42卷 2016-2017页

作者： li Shenggangdepartment of mathematics, Shaanxi normal university, Xi’an 710062, china department of mathematics Shaanxi Normal University Xi’an China

JUST like in classical mathematics, fuzzy unit interval I(L) and fuzzy real line R(L), thebasic and important research objects of fuzzy mathematics, also interest a good few *** 1992, Wang and Xu, by refining the topology of I(L), defined a new fuzzy unit in-terval——H(λ) unit interval I(L), and established the Stone-Cech compactification theoryfor weakly induced L-fuzzy topological spaces. In 1993, Zhang and liu introduced the con-cept of weak inducification of L-fuzzy topological space, and in this way, I(L) is exactly

关键词： real line The connectedness of H unit interval and H line

Output-back fuzzy logic systems and equivalence with feedback neural networks

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Chinese Science Bulletin 2000年第7期45卷 592-596页

作者： li Hongxingdepartment of mathematics, Beijing normal university, Beijing 100875, china department of mathematics Beijing Normal University Beijing China

A new idea, output-back fuzzy logic systems, is proposed. It is proved that output-back fuzzy logic systems must be equivalent to feedback neural networks. After the notion of generalized fuzzy logic systems is defined, which contains at least a typical fuzzy logic system and an output-back fuzzy logic system, one important conclusion is drawn that generalized fuzzy logic systems are almost equivalent to neural networks.

关键词： output-back fuzzy logic systems generalized fuzzy logic systems feedforward neural networks feedback neural networks.

Entire vectors for unbounded normal operators and abstract Cauchy problems

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Chinese Science Bulletin 1997年第15期42卷 1253-1256页

作者： li Yangrongdepartment of mathematics, Southwest normal university, Chongqing 630715, china department of mathematics Southwest Normal University Chongqing China

LET A be a closed operator on a Banach space X, and C~∞ (A)=∩_n~∞=1,D(A^n). The C~∞ vec-tor x is an entire vector for A if sum from n=0 to ∞ (t^n)/(n!)||A^n x||0. We will write ε(A) for the set of all entire vectors for A. It is well known that the set of entire vectors for a self-adjoint operator is dense. Inthis note, we generalize this result to the situation of (unbounded) normal operators. We

关键词： C-semigroups analytic semigroups normal operators entire vectors.

The Star Chromatic Numbers of Some Planar Graphs Derived from Wheels

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Acta Mathematica Sinica,English Series 2002年第1期18卷 173-180页

作者： li De Ming department of mathematics. Capital normal university. Beijing 100037. P. R. china department of mathematics Capital Normal University Beijing P. R. China

The notion of the star chromatic number of a graph is a generalization of the chromatic number. In this paper. we calculate the star chromatic numbers of three infinite families of planar graphs. The first two families are derived from a 3-or 5-wheel by subdivisions. their star chromatic numbers being 2+2/(2n + 1). 2+3/(3n + 1)and 2+3/ (3n - 1), respectively. The third family of planar graphs are derived from n odd wheels by Hajos construction with star chromatic numbers 3 + 1/n. which is a generalization of one resnlt of Gao et al.

关键词： (k,d)-coloring Star chromatic number Planar graph

Nutrient enrichment driven by canopy rainfall redistribution:Mechanism,quantification,and pattern

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Science china Earth Sciences 2024年第5期67卷 1529-1544页

作者： Chuan YUAN Xiaoping yue Yafeng ZHANG Yu ZHANG Yanting HU Qiang TANG li GUO Shuai WANG Xingwu DUAN Wenhua XIANG Xiaohua WEI Xiaoyan li College of Forestry and Biotechnology Zhejiang A&F UniversityHangzhou 311300China Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqing 400715China Shapotou Desert Research and Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Geographical Sciences Hebei Normal UniversityShijiazhuang 050024China Faculty of life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Institute of International Rivers and Eco-securityYunnan UniversityKunming 650091China department of Earth Environmental and Geographic SciencesUniversity of British Columbia(Okanagan)KelownaBritish Columbia V1V 1V7Canada

Vegetation canopies intercept and redistribute rainfall into throughfall and stemflow,which transfer substantial amounts of elements into the soil,influencing soil microbial community,plant survival,and plant community *** advancements in ecohydrological research,the implication of nutrient enrichment resulting from this redistribution of rainfall by canopies remains largely *** address this gap,we conducted a systematic review of 1020 papers published between 2000 and 2022,gathering data on nutrient concentration and enrichment for critical ions(including K^(+),Na^(+),Ca^(2+),Mg^(2+),NH_(4)^(+),Cl^(-),NO_(3)^(-)and SO_(4)^(2-))from the Web of Science and Chinese Knowledge Infrastructure *** aimed to synthesize the mechanisms,quantify the enrichments,and identify global patterns of nutrient enrichment in stemflow and throughfall across climate zones,and vegetation types and *** results of this study indicate that stemflow exhibits,on average,2.1times greater ion concentration(6.13 mg L^(-1))compared to *** particular,among the investigated ions,SO_(4)^(2-)(12.45and 6.32 mg L^(-1))for stemflow and throughfall,respectively,and Cl^(-)(9.21 and 4.81 mg L^(-1))exhibit the highest concentrations in both rainfall redistribution components,while K^(+)(13.7 and 5.8)and Mg^(2+)(5.6 and 2.8)have the highest enrichment *** climate zones,throughfall and stemflow show the lowest ion concentrations but the highest enrichment factors in extremely humid *** the temperature gradient,ion concentrations are the highest in cold climates with no clear patterns observed for enrichment factors with increasing *** addition,shrubs,conifers,mixed forests,and artificial ecosystems demonstrate enrichment factors 1.1 to 3.0 times greater than those of trees,broad-leaved plants,pure forests,and natural *** findings emphasize the need for increased attentions to artificial ecosystems,such as urban

关键词： Ecohydrology Rainfall redistribution Nutrients transport Enrichment characteristics Climate zones

Pointwise estimates for the maximal multilinear singular integral operators

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Science china mathematics 2005年第12期48卷 1696-1706页

作者： HU Guo’en, li Dengfeng & LU Shanzhen department of Applied mathematics, university of Information Engineering, P. O. Box 1001 -747, Zhengzhou 450002, china College of Mathematical and Information Sciences, Henan university, Kaifeng 475001, china department of mathematics, Beijing normal university, Beijing 100875, china 1. department of Applied mathematics University of Information Engineering P.O.Box 1001-747 450002 Zhengzhou China 2. College of Mathematical and Information Sciences Henan University 475001 Kaifeng China 3. department of mathematics Beijing Normal University 100875 Beijing China

Two pointwise estimates relating the maximal multilinear singular integral operators and some classical maximal operators are established. These pointwise estimates imply the rearrangement estimate and the BLO(Rn) est... 详细信息

关键词： multilinear singular integral,maximal operator,BMO (Rn),BLO (Rn).