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Microwave Assisted-extraction of Flavonols from Acanthopanax Senticosus Harms and High-performance Liquid Chromatography Analysis

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Chemical Research in Chinese Universities 2009年第4期25卷 439-442页

作者： LIU Yan-bo Department of Chemistry Baicheng Teacher＇s College Baicheng 137000 P. R. China

Flavonols were extracted from Acanthopanax Senticosus Harms by Soxhlet extraction（SE）,atmospheric pressure microwave-assisted extraction（AMAE） and pressurized microwave-assisted extraction（PMAE）.The influences of experimental conditions,such as concentration of ethanol in the eluent,microwave irradiation time,*** the extraction yield were *** flavonols（hyperin,rutin,quercitrin and quercetin） in the extracts were determined quantitatively by HPLC *** experimental results demonstrate the advantages of PMAE and AMAE over those of conventional SE,that is the extraction time is dramatically reduced,and the yields of flavonols are effective *** the yield of flavonols is higher and the extraction time is shorter by PMAE than those of AMAE,flavonols are easy to be decomposed over a certain time.

关键词： Acanthopanax Senticosus Harms Flavonols Extraction

One ω-Meson Exchange Potential at Finite Temperature

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Chinese journal of nuclear physics 1994年第1期16卷 6-12页

作者： Zheng, Guotong Ning, Pingzhi Su, Rukeng Hangzhou teacher's coll Hangzhou China

On the basis of the field theory at the finite temperature,one ω-mesonexachange potential is *** dependences of ω-meson effective massand renormalized ω-nucleon coupling constant are discussed in the non-relativist... 详细信息

关键词： Field theory Finite temperature Non-relativistic limit

A New Extraction Spectrophotometric Method for the Determination of Phenol in Water

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Chemical Research in Chinese Universities 2000年第1期16卷 5-9页

作者： KANG Chun-li WANG Ying DU Yao-guo LI Run-bo LI Jun and ZHOU Li-ming (Department of Environmental Science, Jilin University, Changchun 130023, P. R. China) JIN Xiang-jun (baicheng Normal college, baicheng 137000, P. R. China) MIAO Fei (Petrochemical I Jilin Univ Dept Environm Sci Changchun 130023 Peoples R China baicheng Normal coll Baicheng 137000 Peoples R China Petrochem Ind Bur Jilin Prov Changchun 130022 Peoples R China

The product of the reaction among phenol, sodium nitroprusside and hydroxylamine hydrochloride in an alkaline solution can be extracted by chloroform in the presence of cetylpyridinium bromide(CPB), on the basis of which a new extraction spectrophotometric method for the determination of phenol in water is developed. The optimum determination wavelength is 720 nm. The molar absorptivity is 1. 05 × 10~5 mol^(-1)· L· cm^(-1) and the detection limit is 4. 0 μg/L. For 30. 0 and 60. 0 μg/L standard solutions, the relative standard deviations are 4. 5% and 2.2 %, respectively(n=6). F values of the statistical analysis show that there is no notable difference between the proposed method and 4-AAP method. The results of the standard addition method for the natural water samples are satisfactory.

关键词： Phenol Extraction Spectrophotometry Water

THE QUADRATIC SYSTEM WITH QUADRATIC ALGEBRAIC CURVE SOLUTION

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Chinese Science Bulletin 1983年第11期28卷 1446-1448页

作者： WANG Dongda baicheng teacher's School Jilin

The number of limit cycles of quadratic system with straight line solutions has been well *** this note,we shall study the quadratic system with quadratic algebraic curves as *** is proved that the quadratic system with quadratic curves as solutions has no other limit cycle than the elliptic limit *** it would be wrong to say that the quadratic system with hyperbola or parabola as solutions may have limit cycles as indicated by Cherkahs in.

关键词： quadratic algebraic straight elliptic cycle wrong hasbeen

Hydrophobic Pocket Modification and Humanized Catalytic Antibodies with Glutathione Peroxidase Activity(Ⅰ)——Preparation and Characterization of Haptenes and Conjugates

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Chemical Research in Chinese Universities 1998年第4期14卷 66-71页

作者： WANG Lin , MA Xue yan, DING Lan, ZHAO Da qing and NI Jia zuan (Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry Chinese Academy of Sciences, Changchun, 130022) FU Ping ping (Norman Bethune Universit Chinese Acad Sci Changchun Inst Appl Chem Lab Rare Earth Chem & Phys Changchun 130022 Peoples R China Norman Bethune Univ Med Sci Changchun 130021 Peoples R China baicheng Normal coll Dept Chem Baicheng 137000 Peoples R China

ＩｎｔｒｏｄｕｃｔｉｏｎＧｌｕｔａｔｈｉｏｎｅｐｅｒｏｘｉｄａｓｅ（ＧＰＸ）ｆｕｎｃｔｉｏｎｓａｓｏｎｅｏｆａｎｔｉｏｘｉｄａｎｔｄｅｆｅｎｃｅｅｎｚｙｍｅｓｔｏｒｅｄｕｃｅａｗｉｄｅｖａｒｉｅｔｙｏｆｉｎｔｒａｃｅ... 详细信息

ＩｎｔｒｏｄｕｃｔｉｏｎＧｌｕｔａｔｈｉｏｎｅｐｅｒｏｘｉｄａｓｅ（ＧＰＸ）ｆｕｎｃｔｉｏｎｓａｓｏｎｅｏｆａｎｔｉｏｘｉｄａｎｔｄｅｆｅｎｃｅｅｎｚｙｍｅｓｔｏｒｅｄｕｃｅａｗｉｄｅｖａｒｉｅｔｙｏｆｉｎｔｒａｃｅｌｕｌａｒｐｅｒｏｘｉｄｅｓ，ｉｎ...

关键词： Glutathione peroxidase(GPX) Catalytic antibody Hydrophobic haptene conjugates

On Double Revised Nodes of S N Bernstein Interpolation Process of the Third Type

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Chinese Quarterly Journal of Mathematics 2008年第4期23卷 559-564页

作者： CHANG Yu-bao WEI Ping YUAN Xue-gang Department of Mathematics Baicheng Teacher＇s College Baicheng 137000 China Department of Mathematics and Information Science Yantai University Yantai 264005 China

In this work, the well-known problem put forward by S N Bernstein in 1930 is studied in a deep step. An operator is constructed by revising double interpolation nodes. It is proved that the operator converges to arbit... 详细信息

关键词： interpolation polynomial uniform convergence the highest convergence order S N Bernstein problem

α-Oxoketene Cyclic S, S-cetals Chemistry-Substitution Reaction of α,α'-Dicinnamoyl Ketene Cyclic S, S-Acetals with Ethylenediamine

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Chinese Chemical Letters 1998年第3期9卷 231-232页

作者： Mei Xin ZHAO Qun LIU Fu Shun LIANG Jing Fu LIU Bao Zhong ZHAO LianZhong LI (Department of Chemistry, Northeast Normal University, Changchun, 130024)(Department of Chemistry, Jilin teacher college, Jilin, 131000) NE Normal Univ Dept Chem Changchun 130024 Peoples R China Jilin teacher coll Dept Chem Changchun 131000 Peoples R China

α,α'-Dicinnamoyl ketene cyclic S, S-acetals 4 were reacted with ethylenediamine to afford α,α'-dicinnamoyl ketene cyclic N,N-acetals 5. This process provides a new method for thesynthesis of 5 in high yield under ... 详细信息

关键词： α,α'-dicinnamoyl ketene cyclic S,S-acetals ethylenediamine substitution reaction,α,α'-dicinnamoyl ketene cyclic N,N-acetals

ON LIMIT CYCLES OF PLANAR QUADRATIC SYSTEM

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Science in China,Ser.A 1983年第10期 1025-1033页

作者：秦元勳索光俭杜星福 Institute of Applied Mathematics Academia Sinica Beijing teacher’s college of baicheng Jilin Province Jiangan Branch of Wuhan Workers and Peasants Normal School

Concerning (1, 3) structure of limit cycles for a planar quadratic system, the restriction of a unique simple singular point at infinity proposed in the previous paper is given up in this article, and a new type of (1, 3) structure is obtained. The differcnce bctwcen them lies in the fact that we use a hyperbola without contact in this paper instead of the straight line without contact as in the last paper.

关键词： ON LIMIT CYCLES OF PLANAR QUADRATIC SYSTEM

How big are the Csorgo-Revesz increments of two-parameter Wiener processes?

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Science China Mathematics 2004年第6期47卷 894-907页

作者： WANG WenshengDepartment of Mathematics, Hangzhou teacher’s college, Hangzhou 310012, China Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing 100080, China Dept. of Math. Hangzhou Teacher's Coll. Hangzhou 310012 China Inst. of Appl. Math. Chinese Acad. of Sci. Beijing 100080 China

In this paper, we prove a theorem on the set of limit points of the increments of a two-parameter Wiener process via establishing a large deviation principle on the increments of the two-parameter Wiener process.

关键词： two-parameter Wiener process increment functional law of the iterated logarithm large deviation.