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1.
Determination of isocarbophos by cathodically sweeping oscilliopolarography is described. In a 1.0×10−5 mol/L sodium dodecylbenzene sulfonate (SDS)+0.1 mol/L HAC-NaAC (pH=4.0) buffer medium, isocarbophos and its alkaline hydrolysate
exhibited sensitive second derivative wave at −0.50 V and −0.48 V respectively. The peak current was linearly proportional
to the concentration of isocarbophos in the range of 5.40×10−6−1.05×10−4 mol/L by detecting isocarbophos directly. The detection limit was 3.60×10−6 mol/L with the relative standard derivation (RSD) of 7.3%. By employing an alkaline hydrolysis, the peak current was linearly
proportional to the concentration of isocarbophos in the range from 7.70×10−7 mol/L to 1.24×10−4 mol/L, and the detection limit was 5.80×10−7 mol/L with RSD of 3.1%. The hydrolysis procedure and the electrode reaction were studied by voltammetry.
Foundation item: Supported by the Foundation of Chinese-France Cooperation Program on Advanced Research
Biography: ZHANG Wu-ming (1929-), female, Professor. 相似文献
2.
A novel spectrofluorimetric method for the determination of L-ascorbic acid is proposed. It is based on the inhibition of
L-ascorbic acid on the formation of 2,3-diaminophenazine, which is an oxidation product ofo-phenylenediamine catalyzed by laccase. The fluorescence (at λcx/λcm=464 nm /530 nnm) was enhanced strongly in the presence of organic media. The mechanism ofo-phenylenediamine oxidation reaction catalyzed by laccase in the presence of L-ascorbic acid is discussed. L-ascorbic acid
is determined in the ethanol, 1,4-dioxane and acetone over the linear range of 4.0×10−7≈1.2×10−4 mol/L, 4.0×10−7≈8.0×10−5 mol/L and 4.0×10−7≈1.0×10−4 mol/L with a detection limit of 1.20×10−5 mol/L, 1.19×10−5 mol/L and 1.24×10−8 mol/L, respectively. The method has been successfully applied to the simple and rapid determination of L-ascorbic acid in
pharmaceuticals and milk powder.
Supported by National Natural Science Foundation of China and the Special Funds of State Education Committe for Doctorate
Research
Huang Zuyun: born in Aug. 1963. Ph.D 相似文献
3.
The electroanalytical method of ferriheme was studied by linear sweep voltammetry in medium of 0.05 mol/L Tris+0.05 mol/L
NH3−NH4Cl buffer at hang mercury drop electrodes (HMDE). Heme exhibits two pair reversible redox peaks and one irreversible peak.
The cathodic peak potentials are−;0.236 V, −0.422 V and −1.408 V respectively. The first and the third peaks can be used for
directly quantitative determination of heme concentrations. The peak currents are good linear relationship with heme concentration
in ranges of 3×10−6–6×10−5 mol/L and 3×10−7–1.5×10−5 mol/L respectively.
Supported by the National Natural Science Foundation of China
Lju Huihong: born in 1965, Lecturer. Visiting scholar from Xiangyang Teacher’s College, Hubei, 441053 相似文献
4.
A series of experimental methods including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test, alkaline
phosphatase (ALP) activity measurement, mineralized function, Oil Red O stain and measurement were employed to assess the
effect of Dy3+ on the osteogenic and adipogenic differentiation of mouse primary bone marrow stromal cells (BMSCs) and the adipogenic trans-differentiation
of mouse primary osteoblasts (OBs). The results showed that Dy3+ had no effect on BMSC proliferation at concentrations of 1×10−8 and 1×10−5 mol/L, but inhibited BMSC proliferation at other concentrations. Dy3+ had no effect on OB proliferation at concentrations of 1×10−10 and 1×10−9 mol/L, but inhibited OB proliferation at other concentrations. Dy3+ had no effect on the osteogenic differentiation of BMSCs at concentrations of 1×10−9 and 1×10−7 mol/L, and promoted osteogenic differentiation of BMSCs at other concentrations at the 7th day. The osteogenic differentiation
of BMSCs was inhibited by Dy3+ at concentration of 1×10−5 mol/L at the 14th day, but promoted osteogenic differentiation of BMSCs at concentrations of 1×10−9, 1×10−8, 1×10−7 and 1×10−6 mol/L with the maximal effect at concentration of 10−6 mol/L. Dy3+ promoted mineralized function of BMSCs at any concentration. Dy3+ had no effect on adipogenic differentiation of BMSCs at concentration of 1×10−7 mol/L, but inhibited adipogenic differentiation of BMSCs at other concentrations. Dy3+ inhibited adipocytic trans-differentiation of OBs at any concentration, suggesting that Dy3+ had protective effect on bone and the protective effect on bone may be mediated by modulating differentiation of BMSCs away
from the adipocyte and inhibiting adipocytic trans-differentiation of OBs which may promote differentiation and mineralization
of OBs. These results may be valuable for better understanding the mechanism of the effect of Dy3+ on pathogenesis of osteoporosis.
Supported by the Foundation for Key Program of Ministry of Education of China (Grant No. 208018) 相似文献
5.
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
6.
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
7.
A coupled chemiluminescence method for the determination of some carboxylic acids was developed, based on their enhancement
the chemiluminescence light emission of the reaction of tirs (2,2′-bipyridine) ruthenium(II) and Ce(IV) in sulfuric acid medium.
The conditions for their determination were optimized. The following detection limits were obtained: oxalic acid, 2.67×10−8 mol/L; propandioic acid, 1.20×10−6 mol/L; pyruvic acid, 1.35×10−8 mol/L; citric acid, 5.10×10−8 mol/L; barbituric acid, 2.48×10−7 mol/L. The proposed method was successfully applied to determination of oxalic acid. The coupled chemiluminescent reaction
mechanism and rate equation are proposed.
Foundation item: Supported by the National Natural Science Foundation of China and the Natural Science Foundation of Hubei
Province
Biography: HAN He-you (1962-), male, Associate professor, phD, graduate candidate 相似文献
8.
Wu Feng-wu Ai Xin-ping Yan Chen-nong He Zhi-ke Meng Hui Zeng Yun-e 《武汉大学学报:自然科学英文版》2002,7(3):341-344
The light emission produced by thiourea in oxidation process by permanganate in acidic solution in the presence of Ru(phen)
2
3
+ is used to determine 1.0×10−5 −1.0×10−5 mol/L thiourea. The limit of detection is 9.8×10−9 mol/L and the relative standard deviation is 1.1% for a 1.0×10−5 mol/L thiourea solution (n=10). The method was applied satisfactorily to the determination of thiourea.
Foundation item, Support by Ministry of Education, Wuhan University and Alumni Association of it
Biography: Wu Feng-wu(1963-), Male, Ph. D, research direction: analytical chemistry. 相似文献
9.
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
10.
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
11.
Poly(neutral red) film modified carbon fibre microelectrodes offer substantial improvement in voltammetric sensitivity and
selectivity towards epinephrine (EP). The poly (neutral red) film was electropolymerized by cycling the potential between
−0.8 V and +0.8 V. The anodic stripping voltammetric response for EP was found to be dependent on accumulation time and potential.
By using a poly(neutral red) film modified carbon fibre microelectrode with a 1 min preconcentration at −1.2 V in biological
phosphate buffer solution (pH=7.4). a good linear relationship between the anodic stripping peak currents and EP concentrations
was obtained in the range of 2.0×10−7⊂2.0×10−5 mol/L. The detection limit was up to 9.0 ×10−8 mol/L. Moreover, 400 times higher concentrations of vitamin C did not interfere with the measurement of EP. This method was
used for determining EP concentrations in epinephrine hydrochloride injection solution with satisfactory results.
Supported by the National Natural Science Foundation of China
Tang Xiaorong: born in 1974, Master 相似文献
12.
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
13.
A second derivative polarographic wave of naphthalene is observed in 50% N, N-dimethylformamide and ammonia-ammonium chloride
medium. The peak potential is about −1.05 V (vs. SCE). The concentration of naphthalene is linear with peak current in the
range of 5.00×10−6 mol/L to 5.00×10−4 mol/L, The detection limit is 2.00×10−6 mol/L. This method can be used to determine naphthalene content of the sample such as coal, mothball and asphaltic bitumen.
The relative standard deviation (RSD) are in the range of 0.38%≈1.30%. The determined recoveries by adding known amounts of
naphthalene to sample solution are in the range of 92%≈101%. This paper also study on the polarographic behavior of naphthalene.
Biography: ZHANG Li-hua (1974-), female, Master. 相似文献
14.
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
15.
The state of Tb3+ is investigated in liposome. When the concentration of PC is below CMC (critical micell concentration), most of Tb3+ is associated with PC, the binding constant is about 3.35×103 L/mol. When the concentration of PC is beyond CMC, most of Tb3+ is dimerized, the dimerization constant is about 3.92×104L/mol. In PC−CH−H2O system, the binding constant of Tb3+−CH complex 2.93×104L/mol is obtained.
Biography:Mu Xiao-jing (1974-), female, MS. 相似文献
16.
We recorded slow vacuolar (SV-type) channel currents of Radish vacuoles successfully for the first time by using the whole-vacuolar patch-clamp recording mode. SV- type currents would increase and threshold potentials of activation would shift towards more negative values with the increase of concentrations of cytosolic Ca2+. When 2.5 mmol/ L LaCl3 and 4 mmol/L EGTA were added to bath solutions, SV-type currents were suppressed remarkably. Then adding LaCl3 with different concentrations to pipette solutions, we found that LaCl3 with higher concentrations (>4 ´ 10-7 mol/L) had a strong inhibitory effect on SV-type currents, while LaCl3 with lower concentrations (≤4 ´ 10-7 mol/L) promoted channel currents. This promoting effect provides an important basis at channel level for researching further the effects of rare earth on physiological activities of plants and the production-increase effects of rare earth fertilizers on crops. 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.
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
19.
QIN Yimin PAN Nina ZOU GuolinCollege of Life Sciences Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2006,11(2):432-436
0Introduction Porphyrinderivativeshavebeenusedasphotosensitizersinphotodynamictherapy(PDT),anewapproachdevel opedforthetreatmentofcancer[1].Cationwater solublepor phyrinsareofconsiderableinterestowingtotheirpossiblebio medicalapplications[2].Inwhich,theinhibiteffectonthe growthmetabolismofE.coliandcancercellHL60ofmeso tetra(4N ethylacetatepyridyl)porphyrin(H2NEAE pp)and itsZn(Ⅱ)complexform(ZnNEAE pp)havebeenrecentlyin vestigated[3,4].Toenhancetumor locationandanticancerac tivitiesofdr… 相似文献
20.
Isotopic geochemical characteristics of helium in garnet and omphacite of eclogite in the Dabie Mountains are discussed. Concentrations
of3He and4He in garnet and omphacite are 3.9 × 10−14–24.0 × 10−14 and 0.48 × 10−7–9.42 × 10−7cm13.g−1, respectively. Values of3He/4He have a range of (1.19–4.63) × 10−7. Helium In the eclogite is derived from both mantle and crust. Isotopic geochemical data of helium indicate that eclogite
in the Dabie Mountains might be formed in depleted mantle and the age of the cologite would be Indo-China epoch. 相似文献