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EflFect of long-term ozone fumigation on growth development and yield of spring wheat in open-top field chamber

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Journal of Environmental Sciences 1990年第3期2卷 27-34页

作者： Wang Xunling, Huang Yunzhu and Wang JingBiology department,lanzhou university,China

The experimental plants were grown in open-top chamber and exposed to 0.26 ppm of ozone for six hrs. per day from seedling stage till ripening. The results showed that the height of plants, rates of earing, flowering, grain forming, ripening and the weight/1000 kernels all declined in fumigated plants in comparison with the controls. The yield lost 76.7%. The actual actions of ozone were that it caused foliar injury and chlorophyll destruction accelerating leaf senescence, reduction of assimilation products. O3.was unfavorable injurious to transport and accumulation of substances to the grains after flowering.

关键词： ozone growth-development spring wheat.

Effect of areca on contraction of colonic muscle strips in rats

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World Journal of Gastroenterology 2002年第2期8卷 350-352页

作者： Dong-Ping Xie Lian-Bi Chen,department of Physiology,Medical College,Shandong university,Jinan 250012,Shandong Province,China Wei Li Song-Yi Qu Tian-Zhen Zheng,department of Physiology,{3. Medical College,{3. 73.000,Gansu Province,China Ying-Li Yang,Northwest Normal university,{3. 73.070,Gansu Province,China Yong-Hui Ding Yu-Ling Wei,Drug Control Institute of Gansu Province,{3. 73.000,Gansu Province,China department of Physiology Medical College Shandong University Jinan 250012 Shandong Province China. xiedping@***

AIM: To investigate the effects of areca on the contractile activity of isolated colonic muscle strips in rats and mechanism involved. METHODS: Each strip (LMPC, longitudinal muscle of proximal colon; CMPC, circular muscle of proximal colon; LMDC, longitudinal muscle of distal colon; CMDC, circular muscle of distal colon.) was suspended in a tissue chamber containing 5 mL Krebs solution (3. degrees C), bubbled continuously with 950 mL.L(-1) O(2) and 50 mL.L(-1) CO(2). The mean contractile amplitude (A), the resting tension (T), and the contractile frequency (F) were simultaneously recorded on recorders. RESULTS: Areca dose dependently increased the mean contractile amplitude, the resting tension of proximal and distal colonic smooth muscle strips in rats (P3. the resting tension of LMDC decreased from 0.71 +/- 0.14 to 0.03.+/- 0.01; the mean contractile amplitude of LMPC increased from -45.8 +/- 7.2 to -3..5 +/- 2.9; the motility index of CMDC decreased from 86.6 +/- 17.3.to 3..8 +/- 9.3. P0.05). CONCLUSION: Areca stimulated the motility of isolated colonic smooth muscle strips in rats. The stimulation of areca might be relevant with M receptor partly.

关键词： Areca Animals Atropine Colon Female Hexamethonium In Vitro Male Muscle Contraction Nicotinic Antagonists Parasympatholytics Plant Extracts Rats Rats, Wistar Research Support, Non-U.S. Gov't

APPLICATION OF SURFACE-ENHANCED RAMAN SPECTORSCOPY FOR CHARACTERIZING HUMIC SUBSTANCES

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Chinese Chemical Letters 1993年第4期4卷 361-362页

作者： Tong Wen NI Analytical And Testing Centre Of Gansu Province,lanzhou 73.000Yu Hui YANG department Of Modern Physics,lanzhou university,lanzhou 73.000

Surface-enhanced Raman Spectroscopy(SERS)has been used to characterize hurnic *** using HNO_3.-roughened silver foils as the enhancing surface,both fluorescence quenching and strong SERS signals have been observed at the same *** results obtained herein show that SERS is a particularly sensitive and highly selective technique for the characterization of humic substances in the environment. Humic substances axe receiving ever-inereasing attention because of their importance in the environment. Very recently,we have reported the first successful application of Raman spectroscopy for characterizing humic *** this present paper,the application of surface-enhanced Raman spectroscopy(SERS)for humic substances has further been *** our knowledge,no such studies have previously been *** results obtained herein dearly demonstrate that SERS has a great deal of promise as an analytical method for“In Situ”characterizing humic substances in the environment.

关键词： SERS SEI APPLICATION OF SURFACE-ENHANCED RAMAN SPECTORSCOPY FOR CHARACTERIZING HUMIC SUBSTANCES

Synthesis, characterization, and biological activities of Pt(Ⅱ) and Pd(Ⅱ2',3.,4',5,7-pentahydroxy flavone

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Rare Metals 2004年第1期23卷 38-42页

作者： TANGHui＇An WANGXiaofang YANGSheng WANGLiufang Chemistrydepartment TianshuiNormalUniversityTianshui741018.China CollegeofChemistryandChemicalEngineering LanzhouUniversityLanzhou730000.China

Pt(Ⅱ) and Pd(Ⅱ) complexes with 2′,3.,4′,5,7-pentahydroxy-flavone weresynthesized and characterized by elemental analysis, molar conductance, IR, ~1HNMR, TG-DTA, UV-Visspectroscopic techniques, and fluorescence analysis. The scavenging effect on the superoxide radical(O_2^-) and the inhibitory effect on lipid peroxides were also investigated. Both the ligand andthe complexes exhibit scavenging effect on superoxide radicals, and the effect of the complexes isgreater than that of the ligand. The Pt(Ⅱ) complex exhibits the strongest scavenging *** Pt(Ⅱ) and Pd(Ⅱ) complexes have the inhibitory effect on lipid peroxides, and the effect ofthe complexes is greater than that of the ligand, but the Pt(Ⅱ) complex has a high effect ofpromoting lipid peroxides.

关键词： inorganic chemistry metal complex 2′,3.,4′,5,7-pentahydroxy-flavone scavenging effect on superoxide radicals inhibitory effect on lipid peroxides

Stereochemical Effects in Mass Spectrometry ( Ⅶ )——Negative Ion Fast Atom Bombardment Mass Spectro-metry of Saccharides with Areneboronic Acids as Reagents

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Chemical Research in Chinese Universities 1992年第3期8卷 231-238页

作者： YANG Hou-jun (department of Chemistry, Tsinghua university, Beijing, 100084)CHEN Yao-zu (department of Chemistry,{3., lanzhou, 73.000)ZHAO Fan-zhi, LI Hai-quan, ZHAI Jian-jun and CHEN Nen-yu (Instrumental Analysis & Research Center,{3., lanzhou, 73.000)

1-Naphthylboronic acid and 2, 4-dimethylphenylboronic acid can react stereospecif-ically with hydroxy groups of saccharides on the probe tip of a fast atom bombardment mass spectrometer to form characteristic negatively-charged boronate ions. On the basis of the relative abundances of these characteristic ions, the epimers of mono- and di-saccharides may be distinguished. This approach was proved to be a simple and effective means for identifying sugars. The collisional activation moss spectra of these characteristic ions are also discussed.

关键词： Reaction mass spectrometry Stereochemical effect Saccharides

CONVERSION OF ACETALS AND KETALS TO CARBONYL COMPOUNDS PROMOTED BY ZrCl_4-NaBH_4

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Chinese Chemical Letters 1991年第1期2卷 47-50页

作者： Shao Zu WU Hui Dong WANG Ning CHENG department of Chemistry,lanzhou university.lanzhou,73.000

In our study on the chemistry of ZrCl_4-NaBH_4,we have found that aldehydes and ketones can be regenerated from acetals and ketals at 3.℃ in Et_2O in high yield The reaction mechanism was discussed.

关键词： MS GC CONVERSION OF ACETALS AND KETALS TO CARBONYL COMPOUNDS PROMOTED BY ZrCl4-NaBH4

A New Iridoid Glycoside and a New Iridoid from Pedicularis kansuensis f. albiflora

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Chinese Chemical Letters 2003年第9期14卷 932-933页

作者： Cheng Shan YUAN, Wei Dong XIE, Xiu Ping YANG, Zhong Jian JIAdepartment of Chemistry, National Laboratory of Applied Organic Chemistry, lanzhou university,lanzhou {3. department of Chemistry Natl. Lab. of Appl. Organ. Chemistry Lanzhou University Lanzhou 730000 China

A new iridoid glycoside 1 and a new iridoid 2 were isolated from the whole plant of Pedicularis kansuensis f. albiflora. Their structures were elucidated by spectroscopie methods.

关键词： Pedicularis kansuensis f. albiflora Scrophulariaceae iridoid glycoside iridoid.

Short cycle structures for graphs on surfaces and an open problem of Mohar and Thomassen

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Science China Mathematics 2006年第2期49卷 212-224页

作者： REN Han & DENG Mo department of Mathematics, East China Normal university, Shanghai 200062, China College of Mathematics & Information Science, Northwest Normal university, {3. 73.070, China department of Mathematics East China Normal University Shanghai China College of Mathematics & Information Science Northwest Normal University Lanzhou China

In this paper we investigate cycle base structures of a (weighted) graph and show that much information of short cycles is contained in an MCB (i.e., minimum cycle base). After setting up a Hall type theorem for base-transformation, we give a sufficient and necessary condition for a cycle base to be an MCB. Furthermore, we show that the structure of MCB in a (weighted)graph is unique. The property is also true for those having a longest length (although much work has been down in evaluating MCB, little is known for those having a longest length). We use those methods to find out some unknown properties for short cycles sharing particular properties in (unweighted) graphs. As applications, we determine the structures of short cycles in an embedded graph and show that there exist polynomially bounded algorithms in finding a shortest contractible cycle and a shortest two-sided cycle provided such cycles exist. Those answer an open problem of B. Mohar and C. Thomassen.

关键词： cycle base facial cycle graph embedding.

EXACT SOLUTIONS FOR BELOUSOV-ZHABOTINSKII REACTION-DIFFUSION SYSTEM

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Applied Mathematics(A Journal of Chinese Universities) 1996年第1期11卷 1-6页

作者： LI ZHIBIN SHI HE department of Mathematics, lanzhou university, lanzhou 73.000 Institute of Systems Science, Academia Sinica, Beijing 100080

We consider the following simplified model for the Belousov-Zhabotinskii(B-Z) reaction:?u/?t=u(1-u-rv)+d?~2u/?x^2,?v/?t=-suv+?~2v/?x^2,where r and s are positive parameters, and d is the diffusing constant for the concen-tration u. Seeking travelling wave front solution and making an ansatz for the solution,we obtain a nonlinear system of algebraic equations. The system is solved using WuElimination and then we are able to find several exact solutions which are of interest.

关键词： Iravelling wave solutions B-Z reaction Wu Eliminat1on,