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Cartesian closedness of categories of completely distributive lattices

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Chinese Science Bulletin 1998年第24期43卷 2059-2063页

作者： ZHANG Dexue 1 and YANG Zhongqiang 2.1. department of Mathematics, Sichuan University, Chengdu 610064. {2. 2. department of Mathematics, shaanxi {4. University, xi’an 710062. china department of Mathematics Sichuan University Chengdu China department of Mathematics Shaanxi Normal University Xi’an China

The category of completely distributive lattices with Scott continuous functions is cartesian closed. Neither the category of completely distributive lattices with arbitrary union preserving mappings nor the category ... 详细信息

关键词： completely distributive lattice continuous lattice cartesian closedness.

NOETHERIAN GT-REGULAR RINGS ARE REGULAR

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Chinese Annals of Mathematics,Series B 1994年第4期15卷 463-468页

作者： LI HUISHI(department of Mathematics, shaanxi {2. Univisity xi’an 710062. china.) 陕西师范大学数学系陕西西安 710062

It is proved that for a left Nootherian z-graded ring A, if every finitely generated gradedA-module has finite projective dimension (i.e., A is gr-regular) then every finitely generatedA-module has finite projective dimension (i.e., A is regular). Some applications of this resultto filtered rings and some classical cases are also given.

关键词： Graded ring Regular ring Projective dimension.

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china Earth Sciences 2006年第5期49卷 505-517页

作者： WANG xianyan1,7, LU Huayu1,2. JI Junfeg3, WANG xiaoyong1,7, ZHAO Jingbo4. HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, xi’an 710075, china 2. {2. of Urban and Resources Sciences, Nanjing University, Nanjing 2.0093, china 3. {2. of Earth Sciences, Nanjing University, Nanjing 2.0093, china 4. department of geography, shaanxi normal University, xi’an 710062. china 5. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., china 6 {2. of {12., Qinghai normal University, xining 810008, china 7. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of Sciences Beijing 100039 China 2. department of Urban and Resources Sciences Nanjing University Nanjing 210093 China 3. department of Earth Sciences Nanjing University Nanjing 210093 China 4. department of geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. department of geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 2. visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4.Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

Relations among the category of topological molecular lattices and certain related categories

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Chinese Science Bulletin 1997年第8期42卷 636-640页

作者： WANG Guojun and LI Yongming1. Institute of Mathematics, shaanxi normal University,{2. 2. department of Basic Science, Northwestern Institute of Architecture Engineering, xi’an 710061, {4. Institute of Mathematics Shaanxi Normal University Xi’an China department of Basic Science Northwestern Institute of Architecture Engineering Xi’an China

TAKING the theory of fuzzy topology and point set topology as background,the theory of topo-logical molecular lattices was first advanced in 1979,and after several generalizationsrefs.[4.5] are its general *** topology and point set topology are both special casesof topological molecular lattices as pointed out in ref.[4.,whereas it seems not clear whetherone can develop the theory of topological molecular lattices by means of methods in

关键词： category pick-up-one principle.

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 {2. 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

Antichains and their application for enumerating ternary logic functions

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Chinese Science Bulletin 1997年第1期42卷 83-84页

作者： WANG Guojundepartment of Mathematics, shaanxi {2. University, xi’an 710062. china department of Mathematics Shaanxi Normal University Xi’an China

MUKAIDONO proposed and systematically investigated the theory of regular ternary logic functions that meets the need of uncertain inferences. The enumeration of ternary logic functions is very complicated and several results have been obtained only in the case where the number of variables is less than 7. In this letter we offer a new possible way to solve the prob-

关键词： Antichains and their application for enumerating ternary logic functions

A FINITE DIFFERENCE METHOD FOR THE MODEL OF WHEEZES

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Journal of Computational Mathematics 1995年第2期13卷 123-129页

作者： Lu Bai-nian (department of Mathematics, shaanxi {2. University, xi’an, shaanxi, {4.) 陕西师范大学数学系陕西西安

In this paper, a finite difference scheme for the linear and nonlinear models of wheezes are given. The stability of the finite difference scheme for the linear model is obtained by using of von Neumann method. Moreover, the convergence and stability of the finite difference scheme for the nonlinear model are studied by the energy inequalities method. By some numerical computations, the relationships between angular frequency and wall position, fluid speed and amplitude are discussed. Finally, the author shows that the numerical results are coincided with Grotberg's theoretical results.

关键词： Math A FINITE DIFFERENCE METHOD FOR THE MODEL OF WHEEZES

Flow-injection Chemiluminescence Sensor for Hydrogen Peroxide with Immobilized Reagents

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Chinese Chemical Letters 1998年第5期9卷 471-472页

作者： Bao xin LI Wei QIN Zhu Jun ZHANG (department of Chemistry, shaanxi {2. University, xi’an 710062. shaanxi normal Univ Dept Chem Xian 710062 Peoples R China

A novel chemiluminescence (CL) sensor for H2.2.combined with flow injection analysis is described in this paper. H2.2.is sensed by the CL reaction with luminol and Co2. bleeding from the ion exchange column with immobilized reagents by hydrolysis. The calibration graph is linear and falls between the range of 4.10(-8) to 1x10(-5) mol/L. A complete analysis could be performed in 1 min. The system was reused for over 50 hours.

关键词： chemiluminescence H2.2.analysis luminol Co(II)

Chemiluminescence flow Sensor for determination of the Ammonium ion

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Chinese Chemical Letters 1998年第8期9卷 743-745页

作者： Bao xin LI Wei QIN Zhu Jun ZHANG(department of Chemistry, shaanxi {2. University, xi’an 710062. shaanxi normal Univ Dept Chem Xian 710062 Peoples R China

A novel chemiluminescence (CL) sensor for NH4. combined with flow injection analysis is presented in this paper. It is based on the inhibition effect of NH4. on the CL reaction between luminol, immobilized electrostatically on an anion-exchange column, and hypochlorous acid electrogenerated on-line. The sensor responds linearly to NH4. concentration in 1.0x10(-6)-4.0x10(-9) g/ml range. A complete analysis could be performed in 1 min. The system is stable for 2.0 determination.

关键词： chemiluminescence flow sensor electrogenerated reagent ammonium ion