最新刊期
卷 31 ， 期 2 ， 2012
- 摘要：Two new 8-hydroxyquinoline derivatives:(E)-2-［2-(2-fluorophenyl)ethenyl］-8-hydroxyquinoline(4a),(E)-2-［2-(pentafluorophenyl)ethenyl］-8-hydroxyquinoline(4b)and their corresponding zinc complexes(5a,5b)were designed,synthesized and identified by 1H NMR,IR,MS spectra and elemental analyses.The aggregation behaviors of Zn(AcO)2 and the ligands:4a，4b in solution were investigated by UV-Vis spectra.The luminescence properties of the complexes:5a，5b were investigated by fluorescence spectra in DMF solution at room temperature.The results showed that the λmax of 4a and 4b were 505 nm(blue and green)and 517 nm(green),and the λmax of 5a and 5b were 559 nm(dark green)and 599 nm(yellow).The λmax of the complexes:5a and 5b exhibited a red shift compared to that of the corresponding ligands:4a and 4b,which can be attributed to the increasing conjugated degree of the complexes,and the λmax of ligands and complexes exhibited evident red shift in the presence of increasing numbers of fluorine.The comparative study of the luminescent properties of 5a and 5b showed that the emission λmax can be tuned by introducing different fluorine numbers.关键词：8-hydroxyquinoline;fluorobenzene;zinc complexes;fluorescence
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发布时间： - 摘要：A new β-cyclodextrin(β-CD) derivative，2，6-di-O-pentyl-3-O-［(methyl)5 (allyl)2］-β-CD was synthesized.The chromatographic properties of this β-CD derivative were examined and studied by using as a chiral stationary phase in capillary gas chromatography，which showed a good separation ability and a chiral selectivity.Nine kinds of aromatic positional isomers were successfully separated with good resolutions，and parts of their separation results were better than that of 2，6-di-O-pentyl-3-O-allyl-β-CD and other β-CD derivatives.And meanwhile，more than ten kinds of chiral compounds were also determined on this stationary phase.Especially，the separations of some propanoic acid esters with α-substitute were better than those on heterocyclic β-CD derivatives reported in the literature.However，the experimental results showed the chiral separation ability of this stationary phase was still similar to the 2，6-di-O-pentyl-3-O-allyl-β-CD by comparison.It indicated that the introduction of methyl to the part of C3-OH positions may improve the selectivity to aromatic positional isomers，but could not affect obviously the chiral separation ability of the β-CD derivative modified allyl groups on the whole of the C3-OH positions.关键词：capillary gas chromatography;β-cyclodextrin derivative;chiral separation
- 2044
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- 900
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- 2
发布时间： - 摘要：A method was developed for the determination of 1,3-dichloro-2-propanol（1,3-DCP）,2,3-dichloro-1-propanol（2,3-DCP） and 3-chloro-1,2-propanediol（3-MCPD） in condimen by gas chromatography-tandem mass spectrometry（GC-MS/MS）.The conditions for sample pretreatment and GC-MS/MS were investigated and optimized.The samples were purified by kieselguhr，eluted with hexane-diethyl ether（5∶5），then derivatised by trifluoroacetic acid anhydride.The detection was carried out by GC-MS/MS in the multiple-reaction monitoring（MRM） mode.Good linear relationships of three analyte were obtained in the concentration range of 0.001-10 mg/L，with correlation coefficients of 0.999 8，0.999 6 and 0.999 7，respectively.The limits of detection were all 0.000 5 mg/kg（S/N=3），and the recoveries ranged from 88% to 97%（n=6）.This method is simple，rapid，low solvent consumption，cheap price of derivative，and the complex matrix disturbance in condimen samples was diminished when MRM mode was adopted.The accuracy,reliability and sensitivity of the method made it was suitable for the determination of three chloropropanols in condimen samples.关键词：gas chromatography-tandem mass spectrometry;condimen;1,3-dichloro-2-propanol;2,3-dichloro-1-propanol;3-chloro-1,2-propanediol;multiple-reaction monitoring
- 3024
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- 1295
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- 3
发布时间： - 摘要：The surface plasmon resonance photocatalyst of Ag-AgBr /Al2O3 was synthesized by chemical precipitation and photochemical reduction method.AgBr nanoparticles were loaded onto the mesoporous aluminium oxide carrier by a precipitation reaction，and some of the AgBr particles were reduced to Ag particles under halogen tungsten lamp irradiation.The samples obtained were characterized by SEM，TEM，XRD and UV-Vis spectroscopy.The photocatalytic properties of catalyst were studied with methylene blue pollutant degraded under a visible light source.The results showed that the degradation rate of 5 mg/L methylene blue reached more than 95% and the removal rate of TOC was 70% under 60 min visible light irradiation.The catalyst showed highly efficient and stable under visible light illumination，and could be applied expansively in the field of developing new pattern visible light plasmon induced photocatalysts.关键词：silver bromide;mesoporous aluminium oxide;photocatalysis;visible light;plasmon resonance effect
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- 2
发布时间： -
Electrochemical Behavior and Determination of Uric Acid at Reduced Graphene Oxide Modified Electrode
摘要：Electrochemical behavior and response of uric acid（UA） was investigated at the chemically reduced graphene oxide（RGO）modified glassy carbon（GC） electrode（RGO/GC） by cyclic voltammetry,chronocoulometry and AC impedance method.The results showed that，in pH 60 PBS buffer solution,the electrochemical oxidation of UA at the RGO/GC modified electrode was irreversible and controlled by diffusion.Some kinetic parameters such as the number（n） of the electron transferred,the effective area（A） of the modified electrode and the diffusion coefficient（D） were calculated to be 2,0.182 cm2 and 1.51×10-6 cm2?s-1,respectively.A good linear relationship between peak current and concentration of UA was observed in the range of 5.0×10-6-1.5×10-4 mol/L,which met the equation of Ip（μA） =6.457+367.5c（mmol/L）（r=0.995 7）.The RGO/GCE modified electrode was successfully applied in the determination of UA with a detection limit of 2.7×10-7 mol/L and recoveries of 98%-100% .关键词：graphene;modified electrode;uric acid;electrochemical behavior- 2580
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- 1007
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- 8
发布时间： - 摘要：A method was developed for the simultaneous determination of four pyridinium and five imidazolium ionic liquid cations by ion-pair chromatography coupled with ultraviolet detection.Chromatographic separations of the ionic liquid cations were performed on a reversed phase silica based column with ion-pair reagent water solution（pH adjusted with citric acid）+acetonitrile as mobile phase by gradient elution.Effects of ion-pair reagent type,acetonitrile concentration,column temperature and elution gradient on retention factor and separation of the ionic liquid cations were investigated.The retention rules of the ionic liquid cations on the column were discussed.The separation of the four pyridinium and five imidazolium ionic liquid cations were achieved using an optimized elution gradient of 1.0 mmol/L 1.heptanesulfonic acid sodium water solution（pH 4.0,A）+acetonitrile（B） with a flow rate of 1.0 mL/min at column temperature of 30 ℃.The optimized elution gradient was as follows: 0-3 min,12% B;3-3.5 min,12%-18% B;3.5-6.5 min,18% B;6.5-7.0 min,18%-25% B;7.0-10 min,25% B;10-10.5 min,25%-30% B;10.5-15 min,30% B.Under the optimal conditions,the four pyridinium and five imidazolium ionic liquid cations could be separated in 15 min.Detection limits（S/N=3） were in the range of 0.31-0.54 mg/L.Relative standard deviations（n=5） for the peak areas were 0.10%-0.75%.The method was successfully applied in the determination of the synthesized ionic liquid samples,with spiked recoveries of 94%-98% .The method is accurate,reliable and practical.关键词：Ion-pair chromatography;ionic liquids;pyridinium cations;imidazolium cations;ultraviolet detection
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- 8
发布时间： - 摘要：An inductively coupled plasma mass spectrometric(ICP-MS) method was established for the determination of trace metal elements,including V，Cr，Mn，Fe，Co，Ni，Cu，Zn，Ag，Cd and Pb in toluene.The toluene were dissolved in ethanol-water-nitric acid system.The organic sampling system and the internal standard element Re were used in this experiment.The experimental conditions,such as RF power，carrier gas，sampling depth，ethanol-water ratio and nitric acid concentration were optimized.The results showed that,under the optimal conditions,the detection limits for the most trace metal elements could reach up to ng /L level.The linear correlation of the method was preferable with correlation coefficient of 0.998 4-1.000.The relative standard deviation(n=3) was less than 8.0% and the relative error was not more than 10%.The toluenes from different factories were analyzed.Results indicated that the concentrations of trace metal elements in the toluenes were obvious different.Therefore,a new identification method for benzenes spilled in ocean was provided by feature analysis of metals in the benzene compounds.关键词：toluene;trace metal elements;inductively coupled plasma mass spectrometry
- 2052
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- 942
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- 0
发布时间： - 摘要：A liquid chromatography tandem mass spectrometric（LC-MS/MS）method was developed for the simultaneous determination of T-2，zearalenone（ZEN） and deoxynivalenol（DON） in wheat.The sample was extracted with acetonitrile-water（80∶20）.The extract was purified with an Amino column（AccuBond-AMINO，500 mg，6 mL）.Three myctoxins were completely separated on a ZORBAX Extend-C18 column（150 mm×2.1 mm,1.8 μm）by gradient elution with methanol and 5 mmol/L ammonium acetate as mobile phase，and detected by positive ion electrospray ionization mass spectrometry（ESI MS） under multiple reaction monitoring（MRM） mode.The results showed that the linearities of T-2,ZEN and DON were in the concentration ranges of 0.5-500，5-500,10-2 000 μg/L，respectively，with correlation coefficients of 0.998 9，0.999 7 and 0.999 1，respectively.The spiked recoveries of T-2，ZEN and DON at three spiked levels in wheat were in the ranges of 86%-94%，80%-101% and 81%-105%，with relative standard deviations（RSDs，n=5） of 2.6%-5.5%，3.6%-8.9% and 2.2%-8.1%，respectively.The limits of detection for T-2，ZEN and DON were 0.5，8.0,10.0 μg/kg，respectively.The method was low cost，sensitive and accurate，and was suitable for the simultaneous determination of T-2,ZEN and DON in wheat.关键词：solid phase extraction（SPE）;liquid chromatography-tandem mass spectrometry （LC-MS/MS）;mycotoxins;wheat
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- 1024
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- 3
发布时间： - 摘要：A novel Keggin-type phosphotungstic acid H7［P(W2O7)6］/2-amino pyridine electropolymerization(PW/PAP) modified glassy carbon electrode was fabricated by electrodepositing H7［P(W2O7)6］ onto 2 amino pyridine electro polymerized glassy carbon electrode.The electrochemical behaviors of PW/PAP modified electrode were investigated by cyclic voltammetry.It is found that there are three redox peaks appeared in the potential range from -0.8 V to 0.2 V in BR buffer solution.The modified electrode showed a good electrocatalysis towards the electro-oxidation of vitamin B2(VB2).The electrochemical behavior of VB2 was surface-controlled.The electron transfer coefficient and rate constant were calculated to be 0.357 and 0.042 s-1，respectively，indicating that the electrochemical reaction of VB2 was a quasi-reversible process.Under the optimal conditions，there was a good linear relationship between the peak currents and VB2 concentrations in the concentration range of 2.4×10-6-1.0×10-4mol/L and 1.0×10-4-5.5×10-4 mol/L，with a detection limit of 1.4×10-6 mol/L.The composite electrode had good stability and reproducibility，and was used in the determination of VB2 in composite vitamin tablets with satisfactory results.关键词：phosphotungstic acid/2-amino pyridine electropolymerized film;vitamin B2;electrocatalysis
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发布时间： - 摘要：A heated single pass spray chamber-based microscale flow injection sampling system was developed for the analysis of platinum in serum samples by inductively coupled plasma mass spectrometry.It consisted of a homemade demountable capillary microflow nebulizer，a single pass spray chamber heated by means of resistive heating，an eight channel sixteen port multifunctional injector valve and a syringe pump equipped with a 10 mL syringe as well as a peristaltic pump.Effects of the dimensions of spray chamber，the heating temperature and the sampling loop volume on the intensity were investigated.The maximum intensity were obtained with the single pass spray chamber with an inner diameter of 9 mm and a length of 6 cm for the heated section.When it was heated up to 90 ℃ and the sampling loop volume was selected to be 5 μL，the intensity of 195Pt was enhanced by a factor of 2.31 and the precision of transient signals for 195Pt was reduced from 5.1% to 2.2%,a signal peak with good configuration was obtained.Compared with the conventional sampling system，the heated single pass spray chamber-based microscale flow injection sampling system offers a little better sensitivity and detection limit in the case of lower sample consumption.The relative standard deviations of peak heights of 10 replicate trials of 10 μg/L standard solution and a serum sample were 2.9% and 3.3%，respectively.The contents of platinum in serum samples by the proposed method agreed well with those obtained by the conventional sampling system.The heated single pass spray chamber-based microscale flow injection sampling system can be applied in many fields，especially in the case of limited or rare samples.关键词：heated spray chamber;microscale flow injection;inductively coupled plasma mass spectrometry;serum;platinum
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- 957
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- 1
发布时间： - 摘要：Based on the comparison of extraction efficiencies of two extraction methods and different organic solvents，an ultrasonic-assisted extraction procedure coupled with high performance liquid chromatography(HPLC) with UV detector was developed for the determination of 4-nonylphenol(4-NP) in soil.The results showed that the extraction efficiency of 4-NP in soil by ultrasonic-assisted extraction with dichloromethane was higher than that by the Soxhlet-extraction method.The results of ultrasonic-assisted extraction with different organic solvents demonstrated that the extraction efficiencies decreased in an order of dichloromethane-methanol(9∶1)＞dichloromethane＞methanol≈acetone. The recoveries of 4-NP in soil at three spiked levels of 10，20,40 mg/kg ranged from 91% to 94% with relative standard deviations(RSDs) of 4.3%-7.2%，and the detection limit of method for 4-NP was 2.0 μg/kg.The method was applied in the determination of 4-NP in soil samples collected from Guangdong Province，and the results showed that the concentrations of 4-NP varied from 5.3 μg/kg to 16 μg/kg by dry weight,which were lower than those obtained from the wastewater irrigated soil of Hebei Province.This method is rapid，sensitive，reproducible and suitable for the determination of 4-NP in soil.关键词：4-nonylphenol;ultrasonic-assisted extraction;high performance liquid chromatography;soil
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- 10
发布时间： - 摘要：The nickel aluminium layered double hydroxides(NiAl-LDH) were synthesized by coprecipitation method.With the layer by layer(LBL) self-assembly of polystyrene sulfonate sodium(PSS) and NiAl-LDH，the PSS/NiAl-LDH multilayer electrode was constructed，and applied in the determination of glucose.The X-ray diffraction，Infrared and SEM spectra of NiAl-LDH showed that it had the typical LDH characteristic peaks and morphology.The UV-Vis spectrum was used to monitor the uniform LBL self-assembly of PSS and NiAl-LDH.Electrochemical study showed that glucose could be effectively catalyzed oxidation with NiAl-LDH mutlitlayer electrode.Under the optimal conditions，the sensor showed a good linear relationship in the range of 5.0×10-7-6.6×10-4 mol/L for glucose with a sensitivity of 8.9×10-4A?L?mol-1 and a detection limit(S/N=3) of 2.8×10-7 mol/L.关键词：nickel aluminium layered double hydroxide;nonenzymatic method;glucose;layer by layer self-assembly;electrode
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发布时间： - 摘要：A highly selective sensing system for turn-on fluorescence assay of norfloxacin(NOR) was proposed based on UV-visible absorption of alizarin red S(ARS) coupled with the use of meso-tetra(N-methyl-4-pyridyl)porphine tetratosylate salt(TMPyP) operative on the fluorescence inner-filter effect(IFE)，in which the combination of two signaling mechanisms allows molecular recoginition event and the signal read-out，independently.The viability of converting the absorption signal of ARS into a fluorescence signal was explored.In the absence of NOR，the absorption spectrum of the ARS has a strong peak at 420 nm，significantly overlapping with the excitation of TMPyP.The formation of NOR-ARS complex shifts the maximum absorbance from 420 nm to 523 nm，which overlap negligibly with the excitation of TMPyP and turn on the proper emission spectrum for TMPyP.Under the optimum conditions，there is a good linear relationship(r2=0.987 8) between relative fluorescence intensity ratio(IF/I0F) of TMPyP and NOR concentration of 10-450 mg?L-1.The limit of detection(S/N=3) was 5 mg?L-1.At the same time，the fluorescence response is highly selective for NOR detection over other metal ions and the common auxiliary materials.The proposed fluorescent NOR assay improved the sensitivity of the UV-Vis method for NOR detection based on the IFE which convert the absorption signal into fluorescent signal.The fluorescent method based on IFE does not require the establishing of any covalent linking between the receptor and the fluorophore.The proposed study offers a novel design to detect drug based on the fluorescence spectroscopy.关键词：inner-filter effect;norfloxacin;alizarin red;turn-on fluorescence assay
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- 0
发布时间： - 摘要：Calcination,potentionmetric titration and compleximetry titration methods are used to determine the contents of CaCO3 in three cigarette papers,the results indicate that the measuring results by calcination are evidently influenced by the calcining heat and calcining time,which has adverse effect for the accuracy.Fiber in the papers are oxidized totally when the cigarette papers are calcined in the condition of 900 ℃ for 2 h .The measuring results by potentionmetric titration and compleximetry titration are rather stable,while the metallic oxides and carbonates in the cigarette papers bring errors for the measuring results by potentionmetric titration method.The impurity ions in the cigarette papers are sheltered by covering reagent in compleximetry titration,so the accuracy of the measuring results is high.The XPS analyzing results show that the CaO is the main component in the ashes of three cigarette papers,and the other chemical compounds such as C,Na2CO3,Na2SiO3,Na3PO4,CaSiO3,Ca3(PO4)2 are also checke.The SEM analyzing results show that the CaCO3 distribute in the fibres exhibits spindle-shaped microcrystallite and spheric cluster.This study presents an accurate method to determine the content of CaCO3 in paper.关键词：cigarette paper;calcium carbonate;calcination;potentiometric titration;compleximetry;XPS;SEM
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- 942
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- 2
发布时间： - 摘要：A gas chromatographic analysis technique with parallel detectors of flame ionization detector and thermal conductivity detector（GC-FID/TCD） was established.The method can be used to determine 16 gases（C1-C6 alkanes,CO2,H2S,O2+N2） of natural gas hydrates simultaneously by one injection.The analysis parameters,such as capillary column,temperature program,column flow,inlet temperature,detector temperature,the reference and makeup flow of TCD were optimized.Under the optimal conditions,good linearities were obtained in the experimental concentration range for the 16 gases with correlation coefficients（r2） of 0.999 03 – 0.999 98.The limits of detection ranged from 0.000 3 mol/mol to 0.046 mol/mol with relative standard deviations（RSDs,n=6） of 1.6%-5.0%.The method was successfully applied in the determinations of gas compositions in the natural gas hydrates from Qilian Mountain Permafrost,South China Sea and laboratory synthetic samples.The result showed that the method was simple,practical,sensitive and reliable,and was suitable for the determination of gases in natural gas hydrates.关键词：natural gas hydrate;gas compositions;GC-FID/ TCD;capillary splitter
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- 1041
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- 11
发布时间： - 摘要：The ligand of 2,6-bis{N-［（1′-hydroxymethyl-2′-phenyl）ethyl］carbamoyl}pyridine and its cobalt（Ⅲ） complex was synthesized and characterized by 1H &13C NMR，IR and elemental analysis，and the complex formula of {［Co（L-2H）］2O2}?2H2O was confirmed.IR spectra showed that 2,6-bis{N ［（1′-hydroxymethyl-2′-phenyl）ethyl］carbamoyl} pyridine acted as a tetradentate ligand，coordinating through two nitrogen atoms of amide and two oxygen atoms of hydroxy.The optical activities of the target ligand and complex were studied by circular dichroism（CD） spectra，and the results showed that they are chiral compounds.关键词：Pyridine-2,6-diamides;cobalt（Ⅲ） complex;circular dichroism
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- 894
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- 2
发布时间： - 摘要：In the presence of sodium dodecyl benzene sulfonate(SDBS),the electrochemical and electrochemiluminescence(ECL) characteristics of the Ru(bpy)2+3- benzhexol hydrochloride(BH) system at Au electrode were studied by ECL and cyclic voltammetric(CV) method.The results showed that the ECL intensity of Ru(bpy)2+3 at Au electrode was enhanced significantly in the presence of BH.In the presence of SDBS,the ECL intensity of Ru(bpy)2+3- benzhexol hydrochloride system was enhanced about 16 times.Based on this,a new electrochemiluminescence method was established for the determination of BH.Under the optimum condition,the enhanced ECL intensity had a good linear relationship with the concentration of BH in the range of 4.0×10-7-1.0×10-4 mol/L,with a detection limit of 1.11×10-9 mol/L.The RSD(n=10) of ECL intensities for the determinations of 1.0×10-5 mol/L BH were 3.2%.The recoveries for the samples were between 96% and 108% with RSD of 4.3%.With high selectivity and sensitivity,this proposed method was applied in the determination of BH in real sample with satisfactory results.关键词：benzhexol hydrochloride;sodium dodecyl benzene sulfonate(SDBS);Ru(bpy)2+3;electrochemiluminescence
- 2325
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- 961
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- 1
发布时间： - 摘要：A nano-Fe2O3 modified glassy carbon electrode（Fe2O3/GCE) was fabricated and the stripping voltammetry behavior of cadmium ion on this modified electrode was studied.The results indicated that the presence of Fe2O3 nanoparticles can effectively enhance the stripping voltammetric response of cadmium ion.In pH 6.0 phosphate buffer solution,cadmium ion was adsorbed onto the surface of Fe2O3 nanoparticles effectively and then reduced at -1.0 V.During the positive potential sweep,the reduced cadmium was oxidized again and an obvious stripping oxidation peak was observed at about -0.85 V.The current of the stripping peak was increased with the increase of cadmium ion concentration.Based on this,a novel method for the determination of cadmium ion was developed based on nano Fe2O3 modified electrode（Fe2O3/GCE).The experimental conditions were optimized.Under the optimum conditions（pH value：6.0,accumulation time：350 s,accumulation potential：-1.0 V),the current response of cadmium ion increased linearly with concentration of cadmium ion in the ranges of 6.0×10-10-1.0×10-8 mol/L and 1.0×10-8- 1.0×10-5mol/L,with a detection limit of 1.0×10-10 mol/L at 3σ.Some common metal ions and cations had no obvious effects on the determination of cadmium ion.This method was used in the determination of cadmium ion in real water samples with satisfactory recovery.关键词：cadmium ion;stripping voltammetry;Fe2O3 nanoparticle;chemical modified electrode;electrochemical detection
- 2166
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- 880
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- 1
发布时间： - 摘要：A method was developed for the determination of cyanogen and hydrogen cyanide residues of fumigant in soil using gas chromatography with purge and trap.The working parameters were optimized using spiked lab blank samples．The results showed that the optimum conditions were found to be as follows:purge time:60 min，purge temperature:80 ℃,purge velocity of carrier gas(N2):40 mL?min-1and 10% sulfuric acid as acidifying reagent.The calibration curves were linear over 0.2-10 mg?L-1 of cyanogen and hydrogen cyanide with correlation coefficients of 0.999 1 and 0.998 3，respectively.Under the optimal conditions，the average recoveries of spiked cyanogen and hydrogen cyanide were 95% and 96%，respectively，with RSDs (n=6) of 3.6% and 5.2%，respectively．The limits of detection(LOD，S/N=3) of cyanogen and hydrogen cyanide were 0.012 and 0. 021 mg?kg-1，respectively，and their limits of quantitation(LOQ，S/N=10) were 0.040 mg?kg-1 and 0.070 mg?kg-1，respectively．After 48 hours of fumigation with cyanogen at 100 mg?kg-1，the residues of cyanogen and its degradation product——hydrogen cyanide in aged soil were 0.32 mg?kg-1 and 5.68 mg?kg-1，respectively．This method was also proved to be convenient in operation with high precision and accuracy，and could be applicable in the determination of cyanogen and hydrogen cyanide residues in aged soil.关键词：soil;cyanogen(C2N2);hydrogen cyanide(HCN);fumigant;purge and trap;gas chromatography
- 2040
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- 1019
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- 3
发布时间： - 摘要：A discrimination method was developed for the rapid and non-destructive identification of fat oxidation in different dairy products by three-dimensional fluorescence spectroscopy.The fluorescence data matrix was decomposed by parallel factor analysis(PARAFAC) and the photosensitive oxidation elements were found from load vectors.After clustering of different samples using score vectors within components，the method of partial least squares discrimination model for different levels of oxidation was established.The yogurt samples with varying degrees of oxidation were collected from different storage environments，in which the lipid oxidation processes of riboflavin and other fluorophores were obtained.The partial least-squares discrimination model of the different storage stages and oxidation levels was established by score vectors.The model specificity and sensitivity of classification were higher than 88。9%，which validated the method in judging the lipid oxidation level of dairy product.关键词：three-dimensional fluorescence;dairy product;fat oxidation;discrimination method;parallel factor analysis（PARAFAC）
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- 899
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- 0
发布时间： - 摘要：Testosterone is the principal anabolic steroid in human body，which plays a key role in promoting physiological function.Because of the extensive needs in clinical diagnosis and sport field，the determination of testosterone has received a considerable attention.In this paper，the methods for the detection of testosterone were summarized，including conventional instrument analysis，immunological detection and electrochemical detection，and the progress in electrochemical detection of testosterone，especially in the construction of electrochemical immunosensors were reviewed.关键词：testosterone;electrochemical;immunosensor
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