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Chinese Science Bulletin 1989年第19期34卷 1663-1665页

作者：童调生张显明童季贤 Hunan Universiry Changsha neijiang teachers' college Neijiang

Suppose x(k+1)=Gx(k)+sum from i=0 to N(H_iu(k-i)), x(k)∈R^n, u(k)∈R. Define the expansive state

关键词： MULTI 油占 Construct write observable matrices arbitrary 脚口二川 detectable

Fuzzy dot ideals and fuzzy dot H-ideals of BCH-algebras

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Applied Mathematics(A Journal of Chinese Universities) 2008年第1期23卷 101-106页

作者： PENG Jia-yin Key Laboratory of Numerical Simulation of Sichuan Province,neijiang 641112,China Dept.of Math.,neijiang teachers college,neijiang 641112,China. Key Laboratory of Numerical Simulation of Sichuan Province Neijiang China Dept. of Math. Neijiang Teachers College Neijiang China

The notions of fuzzy dot ideals and fuzzy dot H-ideals in BCH-algebras are introduced, several appropriate examples are provided, and their some properties are investigated. The relations among fuzzy ideal, fuzzy H-ideal, fuzzy dot ideal and fuzzy dot H-ideals in BCH- algebras are discussed, several equivalent depictions of fuzzy dot ideal are obtained. How to deal with the homomorphic image and inverse image of fuzzy dot ideals （fuzzy dot H-ideals） are studied. The relations between a fuzzy dot ideal （fuzzy dot H-ideal） in BCH-algebras and a fuzzy dot ideal （fuzzy dot H-ideal） in the product algebra of BCH-algebras are given.

关键词： BCH-algebra fuzzy (dot) ideal fuzzy (dot) H-ideal homomorphism.

Ultrasonication solid state chemical reaction synthesis and characterization of nanocrystalline Zn(Oxin)_2·2H_2O (zinc 8-quinolinolate)

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中国有色金属学会会刊：英文版 2006年第B1期16卷 388-392页

作者：李道华 Department of Chemistry and Life Science Neijiang Teachers CollegeNeijiang 641112China

Under near ambient temperature and ultrasonication, nanocrystalline Zn(Oxin)2·2H2O (zinc 8-quinolinolate) was synthesized by solid state chemical reaction. The particle size distribution was relatively uniform, the morphology of the mare was ball like particle. The phase, particle size and morphology of the prepared nanocrystalline were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM) and electron diffraction (ED). The results show that the crystallite product has an average size of about 30 nm. The effects of a series of reaction conditions on the synthesis of Zn(Oxin)2·2H2O by solid state reaction were studied. During the synthesis of nanocrystalline Zn(Oxin)2·2H2O, the solid state reaction conditions such as changing reactant, matching proportion of reactant, adding inert substance, joining a little solvent or surface active solvent and grinding at different times may influence morphology, particle size and the size distribution of final products.

关键词：声波降解固态化学反应合成纳米晶 8-羟基喹啉锌盐表征

1:13 phase formation mechanism and first-order magnetic transition strengthening characteristics in(La,Ce)Fe13–xSix alloys

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Rare Metals 2016年第9期35卷 691-700页

作者： Xiang Chen Yun-Gui Chen Yong-Bo Tang Ding-Quan Xiao college of Engineering and Technology Neijiang Teachers Normal UniversityNeijiang 641002China School of Materials Science and Engineering Sichuan UniversityChengdu 610065China

The effects of the introduction of Ce to La（1-x）CexFe（11.5）Si（1.5） alloys on 1：13 phase formation mechanism,the first-order magnetic phase transition strengthening characteristics,and magnetocaloric property were studied,*** results show that the formation mechanisms of 1：13 and La Fe Si phases in La（1-x）CexFe（11.5）Si（1.5） alloys are the same as those of Ce2Fe（17） and CeFe2 phases in Ce–Fe binary system,*** substitution of Ce in 1：13 phase which is limited can make the first-order magnetic phase transition characteristics strengthen,which can make thermal and magnetic hysteresis increase,the temperature interval of temperatureinduced phase transition decrease,and the critical magnetic field of field-induced magnetic phase transition（HC）increase,*** to the lattice shrink of 1：13phase with the increase in Ce content,the Curie temperatures（TC） show a linear *** maximum change in magnetic entropy gradually increases due to the decrease in temperature interval of temperature-induced phase transition,but the relative cooling capacities are all about80 Jákg-1at magnetic field of 2 T.

关键词： La1-xCexFe1 5Si1 5alloys Short-time annealing Large magnetocaloric effect Magnetocaloric materials

THE DISTURBANCE COMPENSATION AND DELAY COMPENSATION USING EXPANSIVE CONTROL VECTOR

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Chinese Science Bulletin 1989年第20期34卷 1759-1760页

作者：童调生童季贤方定菲黄伟 Hunan University Changsha neijiang teachers' college

Suppose that the control delay system with external disturbance w （k）is where x（0）, u（-1）, u（-2）,…, u（-Mq） are given, and 0=M0q, x∈Rn,u∈Rr,w∈Rm.

关键词： disturbance compensate ponding continued Construct 如叨

Studies of short-time and high-temperature annealing and magnetic property of LaFe_(11.4)Si_(1.6) compound

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Acta Metallurgica Sinica(English Letters) 2011年第5期24卷 390-398页

作者： Xiang CHEN Yungui CHEN Yongbo TANG School of Materials Science and Engineering Sichuan University Chengdu 610065 China Department of Physics and Electronic Informational Engineering Neijiang Teachers College Neijiang 641002 China

The LaFe11.4Si1.6 compounds are prepared by arc-melting and then annealed at different high temperatures from 1323 K （5 h） to 1623 K （2 h）. The powder X-ray diffraction （XRD） and microstructure observations show that large amount of 1：13 phase begins to appear in the LaFe11.4Si1.6 compound annealed at 1423 K （5 h）. In the temperature range from 1423 K to 1523 K, the α-Fe and LaFeSi phases rapidly decrease to form 1：13 phase. The LaFeSi phase is rarely observed by XRD when the as-cast compound is annealed at 1523 K （5 h）. With annealing temperature increasing to 1573 K, LaFeSi phase is detected again in LaFe11.4Si1.6 compound. In LaFe11.4Si1.6 compounds annealed at 1523 K （5 h）, at 1373 K （2 h）＋1523 K （5 h）, and 1523 K （7 h）＋1373 K （2 h）, the impurity phases including small amount of α-Fe and LaFeSi phase reduce in turn. The magnetic measurement shows that LaFe11.4Si1.6 compounds annealed by above three processes keep the first-order of magnetic transition behavior, and Tc are both at about 200 K. But the values of the maximal ASM（T, H） of has large difference, they are 9.94, 12.66, and 13.96 J/（kg.K） under a magnetic field of 0- 2 T, respectively.

关键词： LaFe11.4Sil.6 compound Short-time and high-temperature an-nealing Phase transition Magnetic property

The effect of high-temperature annealing on LaFe_(11.5)Si_(1.5) and the magneto-caloric properties of La_(1-x)Ce_xFe_(11.5)Si_(1.5) compounds

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Rare Metals 2011年第4期30卷 343-347页

作者： CHEN Xiang CHEN Yungui TANG Yongbo School of Materials Science and Engineering Sichuan University Chengdu 610065 China Department of Physics and Electronic Informational Engineering Neijiang Teachers College Neijiang 641002 China

The powder X-ray diffraction patterns of ***.5 compounds annealed at different high temperatures from 1323 K （5 h） to 1623 K （2 h） show that a large amount of 1：13 phase begins to form in ***5 compound annealed at 1423 K （5 h）. In the temperature range from 1423 to 1523 K, ^-Fe and LaFeSi phases rapidly decrease to form 1：13 phase. LaFeSi phase is rarely observed, and the most amount of 1：13 phase is obtained in the compound annealed at 1523 K （5 h）. With the annealing temperature increasing to 1573 and 1623 K, LaFeSi is detected again in the ***.s compound. According to the results of annealing at different high-temperatures, the ***.5 compounds are annealed at high temperatures of 1373 K （2 h）＋ 1523 K （5 h）. The main phase is NaZn13-type phase, and the impurity is a small amount of et-Fe in ***.5 compounds with 0 〈 x 〈 0.35, and there is a large amount of CeaFe17 phase in ***.s. It indicates that the substitution of cerium atoms for La in LaFelLsSil.5 compounds has limit. At the same time, the substitution of Ce for La has large effect on magnetocaloric properties. With increasing Ce content from x = 0 to x = 0.35, the Curie temperature decreases linearly from 196 to 168 K, the magnetic entropy change increases from 16.5 to 57.3 J-kg-kK-1 in a low magnetic field change of 0-2 T, and the thermal hysteresis also increases from 3 K to 8 K.

关键词： rare earth compounds high-temperature annealing magnetocaloric effect phase composition

A study of economic development in Tibet of China based on the ecological economic mode

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Ecological Economy 2006年第3期2卷 235-244页

作者： Zhao Xiaohong He Jia Jiang Li neijiang teachers＇ college Neijiang 641112 P. R. China

The purpose of this paper is to study the issues on keeping the continuous development of Tibetan economy and the relative stability of its ecosystem. Hence, in order to achieve the object, the study analyzes the status quo of economic development in Tibet and the problems of resource exploitation. It especially discusses frailty of Tibetan eco-environment, and evaluates the contradictions between the traditional economic developing mode and the safety of plateau＇s ecosystem. It concludes that there is an inevitable clash between the development of Tibetan economy and the safety of plateau＇s eco-system; this problem cannot be avoided by any decision maker, Therefore, the character of Tibetan econvironment and the requirement of its economic development strategy determine that ecological economy developing mode is the only choice for Tibet. This paper suggests that it should be compensated by the national government to assure that Tibetan economy can keep a higher developing speed. In accordance with the feature of plateau eco-economy system and demand of Tibetan economic development, this paper also suggests several methods to apply the ecoeconomy developing strategy of Tibet.

关键词： Tibet Ethnic group areas Ecological economy Developing mode

Effects of Exogenous Spermidine on PhotosystemⅡof Wheat Seedlings Under Water Stress

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Journal of Integrative Plant Biology 2006年第8期48卷 920-927页

作者： Hui-Guo Duan Shu Yuan Wen-Juan Liu De-Hui Xi Dong-Hong Qing Hou-Guo Liang Hong-Hui Lin Key Laboratory of Bio-resources and Eco-environment （Ministry of Education） College of Life Sciences Sichuan University Chengdu 610064 China Department of Chemistry and Life Sciences Neijiang Teachers＇ College Neijiang 641112 China

The effects of exogenous spermidine （Spd） on lipid peroxidation, relative plasma membrane permeability, photosystem Ⅱ （PSII） gene expression and PSII photochemical activity in water-stressed wheat seedlings were investigated. The decrease in relative water content （RWC）, Chl content, and 2,6-dichlorophenol indophenol （DCIP） photoreduction of PSII, and increases in electrolyte leakage of plasma membranes and malonyldialdehyde （MDA） in water-stressed leaves was alleviated by Spd pretreatment. Furthermore, Western and Northern blot analysis showed that decreases in the PSll major proteins D1, D2 and LHCII and the transcripts of corresponding genes psbA, psbD and cab were also alleviated by Spd pretreatment under water stress. These results suggest that the application of exogenous Spd protects PSII against water stress at both the transcriptional level and the translational level, and allows PSII to retain a higher activity level during water stress. The protective role of Spd in the photosynthetic apparatus also is discussed.

关键词： gene expression photosystem Ⅱ spermidine water stress wheat seedlings.

Magnetocaloric effect of (Gd_(1-x)Nd_x)Co_2 alloys in low magnetic field

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Rare Metals 2008年第4期27卷 350-353页

作者： CHEN Xiang ZHUANG Yinghong YAN Jialin ZHOU Kaiwen LI Kefeng Key laboratory of the Ministry of Education of China for Nonferrous Metal Materials and New Processing Technology Guangxi University Nanning 530004 China Department of Physics and Electronic Informational Engineering Neijiang Teachers College Neijiang 641002 China

The phases and magnetocaloric effect in the alloys （Gd1-xNdx）Co2 with x = 0, 0.1, 0.2, 0.3, and 0.4 were investigated by X-ray diffraction analysis and magnetization measurement. The samples are single phase with a cubic MgCu2-type structure. The To decreases obviously with increasing Nd content from 404 K of the alloy with x = 0 to 272 K of the alloy with x = 0.4; forx = 0.3, the To is 296 K, which is near room temperature. In the samples （Gd1-xNdx）Co2 with x = 0.0, 0.1, 0.2, 0.3, and 0.4, the maximum magnetic entropy change is 1.471, 1.228, 1.280, 1.381 and 1.610 J·kg^-1·K^-1, respectively, in the applied field range of 0-2.0 T. The results of Arrott plots confirmed that the transition type were second order magnetic transition forx = 0, 0.3, and 0.4.

关键词： magnetic refrigeration materials magnetocaloric effect magnetic entropy change phase transition