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1.
CHEN Lihua~ ZHANG Yongkang~ YIN Hong~ LIU Liuzhan~ YANG Zhaoxia~ SHEN Hanxi~ . College of Chemistry Chemical Engineering Jishou University Jishou Hunan China . College of Chemistry Nankai University Tianjin China 《武汉大学学报:自然科学英文版》2006,11(3):704-708
0 IntroductionMaalnadria siusb atr ompajicosr .he aAltrthe pmrisoibnlienmi (n qtihneghtraoopsiucs,QHS,Fig.1) is a sesquiterpene endoperoxide isola-ted fromArtemisia annuaL., an ancient Chineseherbal medicine usedfor treatment of fever and ma-laria.Studies of the structure and activity relation-ship have shownthat endoperoxide groupis essentialfor anti malarial activity of QHS and absence of thismoiety lead to completely loss in activity of thedrug. Many techniques have been developed to de… 相似文献
2.
ZHENG Qi~ CAO Qihua~ LIU Zhihong~ CAI Ruxiu~ . College of Chemistry Environmental Engineering Jianghan University Wuhan Hubei China . College of Chemistry Molecular Sciences Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2006,11(3):677-681
0 IntroductionSltougdiiceasl csoynstceermnsin gharveeac btieveen o txhyeg ei nm psopretcaienst ( oRbjOecSt) iinn bbiioo--medicine and analytical chemistry in recent years[1-4]. Manyi mportant life phenomena and diseases are relatedtotheinter-mediates of ROS[5-7].ROS have beeni mplicated as ani mpor-tant causative factor in cell damage,including apoptosis andnecrosis . Their proposed actions comprise lipid peroxidation,DNAdamage,the mitochondrial respiratory chain destructionand protein mo… 相似文献
3.
Electrochemical behavior of a carbon paste electrode (CPE) modified with nickel(II)-5, 11, 17, 23-tetra-tert-butyl-25, 27-bis(diethylcarbamoylmethoxy)
calix[4]arene (Ni (II)-L) complex and its electrocatalytic activity towards the oxidation of hydrogen peroxide were investigated
by cyclic voltammetric technique in a 5.0×10−2 mol/L NaClO4+1.0×10−3 mol/L NaOH solution. It was found that Ni(II)-L acts as an effective catalyst for the oxidation of hydrogen peroxide. The
modified electrode exhibited a linear response over a hydrogen peroxide concentrations in the range of 2.0×10−5−1.0×10−4 mol/L with a detection limit as low as 1.0×10−6 mol/L. The relative standard deviation was 3.5% for 5 successive determinations of H2O2 at 1.0×10−5 mol/L. The modified electrode was used successfully in rainwater analysis.
Foundation item: Supported by the Natural Science Foundation of Hubei Province (98J040).
Biography: Li Chun ya(1972-), Ph. D. candidate, research direction: electroanalysis and electrosynthesis. 相似文献
4.
Pan Zu-ting Yu Jun-ping College of Chemistry Molecular Sciences Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2004,9(3):353-358
0 IntroductionTriamcinoloneAcetonide,9 fluoro 11β,2 1 dihydroxy 16α,17[(1 methylethylidene)bis (oxy) ] pregn 1,4 diene 3,2 0 dione,Mris 4 34.4 8(abr.TA ) .Itbelongstoaclassofadrenalcortexhormonedrug ,whosefunctionsareaffectionofsugarmetabolism ,anti inflammationandresistancehypersusceptibilityetc.TAcanbesuitabletorheumatoidarthritisanddermatosissuchashypersusceptibilityandneuropathicdermatitis .ThefunctionsofTAisstrongerandlongerthantriamcinolone[1 ,2 ] .ThecommonmethodsofdetectingTAm… 相似文献
5.
SHI Bo’an~ ZENG Danyun~ JI Xinghu~ XI Juan~ AI Xinping~ HE Zhike~ . College of Chemistry Molecular Sciences Wuhan University Wuhan Hubei China . Department of Chemistry Chemical Engineering Hubei Institute for Nationalities Enshi Hubei China 《武汉大学学报:自然科学英文版》2006,11(3):672-676
0 IntroductionThbiep ycroidmipnlee)xru ctahteinoinu mof(Ⅱ r)u t(he Rniuu(mbip,y m)3ai2n +ly) atrnids- t(r2is -,(21’ -,10-phenanthroline)ruthenium(Ⅱ) (Ru(phen)32 +) ,is a kindof sensitive analytical reagent for electrogenerated chemilumi-nescence(ECL) and chemiluminescence(CL) ,on which a par-ticular review has been presented[1]. The earliest publicationon the synthesis of Ru(bipy)32 +appeared in 1936[2], andduringthefollowing30 years ,theinvestigations relatedtothissubstance were only in… 相似文献
6.
The dissolution rate of naked Al sheet in the acidic solutions containing polybutadienoic acid (PBA) with pH value of 0.3∼3.0
at 20∼60°C has been determined by electrometry and gravimetry methods. The form of electroactive Al(III) ions occurred on
the anode and the behavior of electrocoagulation of PBA have been approached. The results indicate that the superior condition
of electrocoagulation of water-soluble nonsaturable low polymer PBA is the adoption of the electroactive Al(III) ions occurred
in electrolyte containing 1.0 g·L−1 PBA+0.2 mol·L−1C6H8O7 citric acid with pH value of 3.0 at 30°C. The mechanism of corrosion-inhibited or electrocoagulation resulted from the electroactive
Al(III) ions coordinate-COOH group of PBA and free ions of citric groups into the aluminum soaps with bicyclic structure are
briefly discussed in this paper.
Supported by the National Natural Science Foundation of China
Tao Yingchu: born in 1943, Professor 相似文献
7.
Zhou Xin-wen Zhan Dan Wang Li-na Liu Qiao-yun Zong Hong-xing Zhang Ke-li 《武汉大学学报:自然科学英文版》2005,10(5):909-912
Lithium iron phosphate coated with carbon (LiFePO4/C) was synthesized by improved solid-state reaction using comparatively lower temperature and fewer sintering time. The carbon
came from citric acid, which acted as a new carbon source. It was characterized by thermogravimetry and differential thermal
analysis (TG/DTA), X ray diffractometer (XRD), Element Analysis (EA) and Scanning electron microscope (SEM). We also studied
the electrochemical properties of the material. The first discharge capacity of the LiFePO4/C is 121 mAh·g−1 at 10 mA·g−1, at room temperature. When the current density increased to 100 mA·g−1, the first discharge capacity decreased to 110 mAh·g−1 and retained 95% of the initial capacity after 100 cycles. The LiFePO4/C obtained shows a good electrochemical capacity and cycle ability at a large current density.
Foundation item: Supported by the National Natural Science Foundation of China (20071026)
Biography: ZHOU Xin-wen (1980-), male, Master, research direction: inorganic material chemistry. 相似文献
8.
Han Dong-dong Cheng Gong-zhen Ji Zhen-ping Zhang Bing-guang . College of Chemistry Molecular Sciences Wuhan University Wuhan Hubei China . The State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu China 《武汉大学学报:自然科学英文版》2004,9(1):93-98
0 IntroductionThemetalionsinmetallamacrocylesformedbysupramolecularself assemblycantaketrigonal,square planar,andtetrahe dralconfiguration[1 ,2 ] .Metallacrownisaspecialclassofmetalla macrocyle,theyareanalogoustocrownethersinbothstructureandfunctionexceptthatthemetalionsarenowtakingthepositionsofcoordinationatomsincrownether[3,4] .Themetallacrownswithdifferentnumberof [M—N—O]repeatunithavedifferentcavitysizes,suchas 9 MC 3[5 7] ,12 MC 4 [4,8 1 4 ] and 15 MC 5 [1 5] .Thereportedazameta… 相似文献
9.
An electrochemical method for the simultaneous determination of lead(II) and Cadmium(II) with a calix[6]arene modified carbon
paste electrode (CPE) has been developed. Pb2+ and Cd2+ were accumulated at the surface of the modified electrode via formation of chemical complexes with calix[6]arene, and reduced
at 1.40 V. During the following anodic potential sweep, reduced lead and cadmium were oxidized, and two well-defined striping
peaks appeared at about −0.60 V and −0.84 V. Compared with a bare carbon paste electrode, the calix[6]arene modified CPE greatly
improves the sensitivity of determining lead and cadmium. The stripping peak currents change linearly with the concentration
of Pb2+ 3.0×10−8–8.0×10−6 mol·L−1 and with that of Cd2+ 6.0×10−8–1.0×10−5 mol ·L−1. The detection limits of Pb2+ and Cd2+ are found to be 8.0×10−9 mol·L−1 and 2.0×10−8 mol·L−1, respectively. The modified carbon paste electrode was applied to determine trace levels of lead and cadmium in water samples.
Comparing with that of atomic absorption spectrometry, the results suggests that the calix[6]arene modified CPE has great
potential for the practical sample analysis.
Foundation item: Supported by the National Natural Science Foundation of China (60171023)
Biography: JI Xiao-bo (1980-), male, Master, research direction: electroanalytical chemistry. 相似文献
10.
The thermokinetic reduced extent equations of reversible inhibitions for Michaiels-Menten enzymatic reaction were deduced,
and then the criteria for distinguishing inhibition type was given and the methods for calculating kinetic parameters,K
M,K
i andv
m were suggested. This theory was applied to inverstigate the inhibited thermokinetics of laccase-catalyzed oxidation ofo-dihydroxybenzene bym-dihydroxybenzene. The experimental results show the inhibition belongs to reversible competitive type,K
M=6.224×10−3 mol·L−1,K
i=2.363×10−2 mol·L−1.
Xiong Ya: born Sep. 1961, Ph. D. graduate student. Curent research interest is in biothermochemistry research
Supported by the National Natural Science Foundation of China 相似文献
11.
Wu Yun-hua Fei Jun-jie Dang Xue-ping Hu Sheng-shui College of Chemistry Molecular Sciences Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2004,9(3):366-370
0 IntroductionDetectionofammoniumionisveryimportantinmanyfields,suchashealthcare,agriculture ,cultivationandenviron mentalpollutioncontrol.Severalanalyticalmethodshavebeende velopedforammoniumdeterminationincludingionchromatography ,spectrophotometry,fluorimetryandchemiluminescence .MostofthemarebasedonspectrophotometryusingtheBerthelot reactionbetweenammonium ,phenol,andhypochloriteleadingtothefor mationofanindophenoldye[1 ] .Thereactiontimeisaboutanhour,andsomedissolvedorganicnitrogencompo… 相似文献
12.
DAI QiZhou ZHOU MingHua LEI LeCheng ZHANG XingWang 《科学通报(英文版)》2007,52(12):1724-1727
A novel advanced oxidation process——wet electrocatalytic oxidation (WEO) was studied with p-nitrophenol as model pollutant and β-PbO2 electrode as the anode. Compared with the effect of the individual wet air oxidation (WAO) and electrochemical oxidation (EO), the effect of WEO showed syn- ergistic effect on COD removal under the conditions of temperature 160℃, C=1000 mg·L-1, PN2=0.50 MPa, PO2=0.9 MPa, current density = 3 mA·cm-2, Na2SO4 3 g·L-1. And the synergistic factor got the best value of 0.98 within 120 min after 180 min treatment. The synergistic factor was studied after 120 min treatment at 100℃, 120℃, 140℃ and 160℃, and the effect of 120℃ was the best with the value of 1.26. Possible mechanism for the synergistic effect was discussed based on the analysis of free-radical generation and intermediates detected by HPLC and GC/MS. 相似文献
13.
Wen Qin-xue Chen Zhi-qiang Lu Bing-nan Wen Yan School of Municipal Environmental Engineering Harbin Institute of Technology Harbin China Environmental Protection Technology Ltd. of Harbin Institute of Technology Harbin China 《武汉大学学报:自然科学英文版》2004,9(3):388-394
0 IntroductionThejetloopreactorhasthecharacteristicsofbothjetandloopflow .Ononehand ,theairsuckedinisdispersedintosmallgasbubblesbecauseoftheshearingforcecausedbythehighvelocityjet,producinganincreasedinterfacialcontactbe tweengasandliquid ,thusthemasstransferefficiencyisin creased .Ontheotherhand ,aregularloopflowisformedbecauseofmutualimpetusofbothjetandair lift,thusdramaticallyim provestheperformancesofmixture ,diffusion ,masstransferandheattransferofthematerial.Withoutmechanicdriving ,the… 相似文献
14.
WANG Yongjuan HAN Wenbao LI Shiqu 《武汉大学学报:自然科学英文版》2006,11(6):1862-1864
Rotation symmetric function was presented by Pieprzyk. The algebraic configuration of rotation symmetric(RotS) function is special. For a Rots n variables function f(x1, x2, …, xn) we have f(ρn^k (x1, x2, …xn))=f(x1, x2, …, xn) for k=0, 1, …, n-1. In this paper, useing probability method we find that when the parameters of RotS function is under circular translation of indices, its walsh spectrum is invariant. And we prove the result is both sufficient and necessary. 相似文献
15.
Wang Jin |long Yuan Liang |jie Yang Yi |yong Sun Ju |tang Zhang Ke |li College of Chemistry Molecular Sciences Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2003,8(3):853-856
0 IntroductionInrecentyears,studiesonBinghamfluid ,suchasElec trorheologicalfluid ,areactivelypursued[1 6] .Rheologicaltechniqueshavebeenplayinganimportantroleinsyntheticchem istry .Therheologicalphasereactionmethodisthe processofpreparingcompoundsormaterialsfromasolid liquidrheologicalmixture.Thatis,thesolidreactantsarefullymixedinapropermolarratio ,andmadeupbyaproperamountofwaterorothersolventstoaBinghambodyinwhichthesolidparticlesandliquidsubstanceareuniformlydistributed ,sothattheprodu… 相似文献
16.
A new chemiluminescence (CL) method for the determination of tetracycline and oxytetracycline is developed, based on the CL
reaction of tetracycline and oxytetracycline with Ru (bipy)3
2+ and Ce (IV). In sulfuric acid medium, the CL emission is generated upon continuous oxidtion of Ru(bipy)3
2+ by cerium (IV). The emission intensity is greatly enhanced when tetracycline and oxytetracycline are introduced into the
reaction system after acid degradation. Under the optimum conditions, the calibration curves are linear over the range of
8.0×10−8∼4.0×10−6 mol/L for tetracycline and of 2.0×10−7∼4.0×10−5 mol/L for oxytetracycline, with the detection limits are 4.2×10−8 mol/L for tetracycline and 1.5×10−7 mol/L for oxytetracycline, respectively. The proposed method was used for the determination of tetracycline and oxytetracycline
in pharmaceutical formulations with good results.
Foundation item: Supported by the National Natural Science Foundation of China and the Natural Science Foundation of Hubei
Province.
Biography: HAH He-you (1962), male, Associate profeddor, Ph.D graduate candidate. Present address, Department of Chemistry,
Huainan Teacher's College, Huainan. 相似文献
17.
Zhenrong Sun Shenyi Wang Yanping Huang Jiyun Lin Liangen Ding Zugeng Wang 《科学通报(英文版)》1998,43(5):399-402
The nonlinear refractive indexesn
2 for the ethanol solutions of 1, 10-phenanthroline (2.0 × 10−3 mol · L−1), [bis(l, 10-phenanthroline) lanthanum (III)] nitrate (1.0 × 10−3 mol · L−1), and [nitrato-fluoracil-bis (1, 10-phenanthroline) lanthanum (III) ] nitrate (1.0 × 10−3 mol · L−1) are first measured, the third-order nonlinear optical susceptibilities χ(3) and 〈γ〉 are calculated, and the mechanisms of the third-order optical nonlinearities enhanced by lanthanum (III) are discussed
preliminarily. 相似文献
18.
The chemiluminescence (CL) of luminol-Cu (II) was applied to HPLC determination of ascorbic acid, which was separated by a
C18 reverse-phase column with a mobile phase of 0.25 mol/L HAc. The eluted ascorbic acid was mixed with 0.3 mmol/L luminol and
0.05 mol/L CuSO4. The light emission from the reaction of Cu(II) oxidized ascorbic acid and luminol was detected by a modified luminometer.
The detection limit was 3.6×10−6 mol/L for ascorbic acid at aS/N ratio of 3, and the linear calibration range was 2×10−4–2×10−3 mol/L. The relative standard deviation for 5 replicate injections of 1×10−3 mol/L ascorbic acid was calculated as 4.3%. The method was successfully applied to determination of ascorbic acid in juice
beverage.
Foundation item: National Natural Science Foundation of China (29605001)
Biography: Wu Feng-wu(1963-), male, research direction: analytical chemistry. 相似文献
19.
The fluorozirconate glasses ZBLANP (ZrF4−BaF2−LaF3−NaF−PbF2) doped with different Yb3+ concentration were prepared. The Raman spectra and absorption spectra are measured to substantiate the existence of phonon-assisted
emission. After analyzing the normalized absorption spectra of samples with different Yb3+-doped concentration, we calculated the maximum cooling effect in the 3 wt% Yb3+-doped sample pumped at 1 012.5 nm. The corresponding cooling capability is about −4.09 °C/W and the cooling efficiency reaches
1.76%.
Foundation item: Supported by the Key Science Foundation of Wuhan (9601P0223)
Biography: Xu Tian-ming (1978-), female, Master candidate, research direction: information optics and nonlinear optics. 相似文献
20.
WANG Juan~ TANG Ping~ ZHAO Fa-qiong~ ZENG Bai-zhao~ . College of Chemistry Molecular Sciences Wuhan University Wuhan Hubei China . Department of Environmental Engineer Jianghan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2005,10(5):913-918
0Introduction Epinephrine(EP)isanimportantcate cholamineneurotransmitterinthemammaliancentralnervoussystem,whichissecretedbythesu prarenalglandalongwithnorepinephrine.Itisgen erallyusedtotreathypertension,bronchialasthma,organicheartdisease,andincardiacsurgeryand myocardialinfarction[1].VariousmethodshavebeendevelopedforEPstudy,suchascapillaryelectro phoresis(CE)[2],highperformanceliquidchroma tography(HPLC)andflowinjectionanalysis(FIA)[3].Numerousobservationsontheelectro chemicalbehavio… 相似文献