最新刊期
卷 36 ， 期 8 ， 2017
- 摘要：A rapid analytical method was developed for the screening of 14 carcinogenic and sensitizing colorants in toys(e.g. crayon, temporary tattoo sticker and modeling clay) using ionization coupled with ion mobility spectrometry. Without any tedious pretreatment, sampling, extraction and ionization were integrated by paper spray or extraction nano-electrospray. The instrumental analysis time for a single ion mobility spectrometry run was less than 16ms.The suspicious positive samples were subjected to further verification by ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The limits of detection(LODs) for the 14 carcinogenic and sensitizing colorants in toys ranged from 0.5mg/kg to 2mg/kg.The established method is simple, convenient and suitable for rapid, on-site screening of toy products.关键词：paper spray;extraction nano-electrospray;ion mobility spectrometry;toys;carcinogenic and sensitizing colorants
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发布时间： - 摘要：A modified QuEChERS sample preparation combined with high performance liquid chromatography-heated electrospray ionization-tandem mass spectrometric(HPLC-HESI/MS/MS) method was established for the simultaneous determination of niclosamide(NIC)，chloramphenicol(CAP)，thiamphenicol(TAP)，florfenicol(FF) and florfenicol amine(FFA) in plasma，muscle，skirt，liver and kidney of Chinese soft-shelled turtle(Trionyx sinensis).The sample was extracted and purified using a modified QuEChERS method，and ammoniate acetonitrile and octadecyl silane(C18) were chosen as extractant and purification，respectively. The mobile phase comprised of methanol and water，and the flow rate was set at 0.3mL/min.The sample prepared was separated on a Waters Symmetry? C18(2.1mm×100mm，3.5μm) column,and determined in the positive and negative ion multiple reaction monitoring mode through polarity switching between time segments.CAP，TAP，FF and FFA were quantified by internal standard calibration curve method，and NIC was used the external standard matrix-matched standard curve method.Good linearities were observed in the range of 0.3-100μg/L for five analytes，with correlation coefficients not more than 0.9987.The average recoveries of 5 analytes at the spiked level of 1-20μg/kg in plasma，muscle，skirt，liver and kidney of Chinese soft-shelled turtle(Trionyx sinensis) ranged from 77.9% to 105.3% with relative standard deviations(RSD) of 2.7%-10.5%.The detection limits(LOD) for NIC，CAP，TAP，FF and FFA in Chinese soft-shelled turtle tissues were 0.5，0.1，0.5，0.5,0.5μg/kg，and the quantitation limits(LOQ) were 1.0，0.3，1.0，1.0,1.0μg/kg，respectively. The method is simple，accurate，highly sensitive，and is suitable for the simultaneous determination of NIC，CAP，TAP，FF and FFA residues in Chinese soft-shelled turtle tissues.A modified QuEChERS sample preparation combined with high performance liquid chromatography-heated electrospray ionization-tandem mass spectrometric(HPLC-HESI/MS/MS) method was established for the simultaneous determination of niclosamide(NIC)，chloramphenicol(CAP)，thiamphenicol(TAP)，florfenicol(FF) and florfenicol amine(FFA) in plasma，muscle，skirt，liver and kidney of Chinese soft-shelled turtle(Trionyx sinensis).The sample was extracted and purified using a modified QuEChERS method，and ammoniate acetonitrile and octadecyl silane(C18) were chosen as extractant and purification，respectively. The mobile phase comprised of methanol and water，and the flow rate was set at 0.3mL/min.The sample prepared was separated on a Waters Symmetry? C18(2.1mm×100mm，3.5μm) column,and determined in the positive and negative ion multiple reaction monitoring mode through polarity switching between time segments.CAP，TAP，FF and FFA were quantified by internal standard calibration curve method，and NIC was used the external standard matrix-matched standard curve method.Good linearities were observed in the range of 0.3-100μg/L for five analytes，with correlation coefficients not more than 0.9987.The average recoveries of 5 analytes at the spiked level of 1-20μg/kg in plasma，muscle，skirt，liver and kidney of Chinese soft-shelled turtle(Trionyx sinensis) ranged from 77.9% to 105.3% with relative standard deviations(RSD) of 2.7%-10.5%.The detection limits(LOD) for NIC，CAP，TAP，FF and FFA in Chinese soft-shelled turtle tissues were 0.5，0.1，0.5，0.5,0.5μg/kg，and the quantitation limits(LOQ) were 1.0，0.3，1.0，1.0,1.0μg/kg，respectively. The method is simple，accurate，highly sensitive，and is suitable for the simultaneous determination of NIC，CAP，TAP，FF and FFA residues in Chinese soft-shelled turtle tissues.关键词：Chinese soft-shelled turtle;niclosamide;amphenicols;modified QuEChERS;high performance liquid chromatography-heated electrospray ionization-tandem mass spectrometry(HPLC-HESI/MS/MS)
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发布时间： - 摘要：A new method was developed for the determination of 10 kinds of salicylamides，including 5-chlorosalicylanilid，4′-bromosalicylanilid，3′,4′-dichloro-salicylanilid，4′,5-dichloro-salicylanilid，3′,4′,5-trichloro-salicylanilid，5-bromo-4′-chlorosalicylanilide，3,5-dibromo-salicylanilid，4′,5-dibromo-salicylanilid，3,4′,5-tribromo-salicylanilid and 3,3′,4′,5-tetrachloro-salicylanilid in foods of animal origin using solid phase extraction（SPE） combined with ultra-performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS）.Samples were extracted using acetonitrile, and purified with an amino（NH2） SPE column. The eluent was concentrated by nitrogen gas blowing.10 target compounds were separated on a T3 column（100mm×2.1mm，1.8μm） by gradient elution with methanol-0.1% formic acid as mobile phase，ionized by negative electrospray ionization（ESI-），detected under multiple reaction monitoring（MRM） mode，and quantified by the external standard method. Under the optimized condition，the calibration curves of 10 kinds of salicylamides were linear in a certain concentration range with correlation coefficients（r2） no less than 0.9957.The limits of detection（LODs，S/N=3） and limits of quantitation（LOQs，S/N=10） for the target compounds were in the ranges of 0.5-1.0μg/kg and 1.5-3.0μg/kg，respectively. The average recoveries at three spiked levels ranged from 81.0% to 106%，with relative standard deviations（RSD，n=6） no more than 7.5%.The method was suitable for the identification and quantification of 10 kinds of salicylamides in foods of animal origin.关键词：foods of animal origin;solid phase extraction（SPE）;salicylamides;ultra-performance liquid chromatography tandem mass spectrometry（UPLC-MS/MS）
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发布时间： - 摘要：A copper oxide-overoxidized polypyrrole-reduced graphene oxide composite film(CuO-OPPy-ERGO/CCE) modified electrode was fabricated by using layer by layer electrochemical deposition technique.Firstly,a polypyrrole(PPy)-graphene oxide(GO) composite film was prepared by electropolymerization of pyrrole while using GO as the anionic dopant.After the electrochemical reduction in 0.10mol/L NaCl solution and peroxidation in 0.10mol/L NaOH solution, an overoxizied polypyrrole-reduced graphene oxide(OPPy-ERGO) composite film was obtained. Then, copper oxide was electrochemically deposited on this OPPy-ERGO film, and the modified electrode was obtained. The surface morphology and the electrochemical behavior of this modified electrode were investigated by scanning electron microscopy(SEM) and cyclic voltammetry. Furthermore, the electrochemical behavior of glucose on this electrode was also investigated carefully. The results showed that this modified electrode exhibited a high electrocatalytic activity and a good anti-interference ability for the oxidation of glucose. Under the optimum conditions, the linear range for the determination of glucose by amperommetry was in the range of 5.0×10-7-1.0×10-3mol/L.The detection limit(3Sb=3) and the sensitivity was 2.0×10-7 mol/L and 121.8μA/(mmol?L-1), respectively. The modified electrode was successfully used to determine glucose in human serum sample with recoveries of 96.0%-110.1%.关键词：copper oxide;overoxidized polypyrrole;reduced graphene oxide;glucose;electrocatalysis
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发布时间： - 摘要：The aim of this paper was to understand the concentrations of perfluorinated compounds(PFCs) and common metal elements in children’s blood and provide data for the assessment of children’s health. The samples were extracted by protein precipitation, and then detected by high liquid chromatography-electrospray-mass spectrometry(HPLC-MS/MS). Meanwhile, the samples were digested with graphite automatic instrument, and then calcium(Ca), magnesium(Mg), iron(Fe), zinc(Zn), copper(Cu) and manganese(Mn) in samples were determined by inductively coupled plasma-mass spectrometry(ICP-MS).The PFCs in children’s blood were widely detected. The frequencies and concentrations of perfluorooctane sulfonate(PFOS) and perfluorooctanoic acid(PFOA) were the highest, whereas some other PFCs with higher concentrations were found in some blood samples. A negative correlation was found between the concentrations of PFCs and the children’s age. There was no gender difference in the concentrations of PFCs except perfluorobutane sulfonate. The concentrations of Ca, Mg, Fe, Zn, Cu and Mn were in normal range. The PFCs in children’s blood were widely determined. Concerns regarding children exposure to PFCs are needed. Focus should be paid not only on PFOS and PFOA, but also on other PFCs in the future monitoring.关键词：perfluorinated compounds;metal elements;HPLC-MS/MS;ICP-MS
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发布时间： - 摘要：An ultra performance liquid chromatography-tandem mass spectrometric(UPLC-MS/MS) method with solid phase extraction(SPE) was applied in the simultaneous determination of phenylbutazone and aminopyrine in anti-acne cosmetics.The sample was ultrasonically extracted with acetonitrile,and then purified on an Oasis HLB solid phase extraction column.The separation was performed with an Eclipse XDB-C18(3.5 μm，4.6 mm×150 mm) column,using a mixture of methanol and 10 mmol?L-1 ammonium acetate as mobile phase by gradient elution at a flow rate of 0.5 mL?min-1.The analytes were detected with electrospray ionization source in positive ion mode(ESI+) and multiple reaction monitoring(MRM),and quantified by matrix standard curve.The calibration curves of phenylbutazone and aminopyrine were linear in the range of 2.0-200.0 μg?L-1 with correlation coefficients(r2) larger than 0.99.The limits of detection(LOD) and limits of quantitation(LOQ) of the method were 1.5,0.8 μg?kg-1 and 4.9,2.7 μg?kg-1,respectively.The recoveries of phenylbutazone and aminopyrine were in the range of 77.8%-93.4%at three spiked levels,with intra-day and inter-day relative standard deviations(RSD) of 2.4%-7.8% and 3.6%-9.5%,respectively.With fast detection,high sensitivity and low detection limit,the method is able to provide a scientific basis and a technical support for monitoring residues of phenylbutazone and aminopyrine in cosmetics and product quality control.关键词：ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS);cosmetics;phenylbutazone;aminopyrine;solid phase extraction(SPE)
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发布时间： - 摘要：An analytical method was established for the simultaneous determination of 17 pesticide residues in flour by ultra performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS).The QuEChERS method was validated for the extraction.In this method,the samples were extracted with 0.1%(by volume)acetic acid-acetonitrile solution,and cleaned-up by PSA and C18 adsorbents,then determined by UPLC-Q-TOF/MS with electrospray ionization in positive mode.The quantification analysis was performed by the external standard calibration.A database including accurate mass and fragment ions information was established.The correlation coefficients(r)were more than 0.995 in the linear range of the 17 pesticides.The limits of quantitation(LOQs)of the method were in the range of 5.0-10.0 μg/kg.The recoveries at three spiked levels were between 70.3%and 114.9%with relative standard deviations(RSDs,n=6)of 0.4%- 11.7%.With the advantages of simplicity and good stability,the method is available for practical application.关键词：ultra performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF/MS);pesticide residues;flour;QuEChERS
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发布时间： - 摘要：A sensitive solid phase extraction/high performance liquid chromatography-tandem mass spectrometric（SPE/HPLC-MS/MS） method was developed for the determination of kasugamycin residues in cucumber and soil.The cucumber and soil samples were extracted with 1% formic acid methanol solution and 0.5% formic acid water solution,respectively,and cleaned up with MCX solid phase extraction column,then separated on a Waters Xbridge BEH Amide column using acetonitrile-0.2% formic acid as mobile phase by gradient elution.The qualitative and quantitative analyses were performed under positive electrospray ionization（ESI+） in multiple reaction monitoring（MRM） mode,with the matrix matched calibrations.The calibration curves showed good linearities in the concentration range of 2-250 μg/L with correlation coefficients more than 0.999.The limits of detection（LOD） and the limits of quantitation（LOQs） were 0.002 mg/kg and 0.008 mg/kg,respectively.The average recoveries at four spiked levels（0.008,0.040,0.200,0.400 mg/kg） were in the range of 77.5%-97.0% for cucumber and soil,with relative standard deviations（RSDs） of 2.6%-10.7%.The method is simple,rapid,sensitive,accurate and reproducible,and could meet the requirements for analysis of kasugamycin residues in cucumber and soil samples.The method was applied in the detection of the field samples,and the contents of kasugamycin residues in cucumber and soil were found not more than 0.053 mg/kg and 0.013 mg/kg,respectively,which were below the maximum residue limits（MRL） for kasugamycin in cucumbers defined by China（0.2 mg/kg）.关键词：kasugamycin;cucumber;soil;high performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS）;solid phase extraction（SPE）
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发布时间： - 摘要：A novel modified electrode（HMCS/SPCE) was developed to electrochemically detect nicotine based on screen-printed carbon electrodes（SPCE) modified with hollow mesoporous carbon spheres（HMCS) synthesized through one step process.HMCS and HMCS/SPCE were characterized by scanning electron microscopy（SEM),transmission electron microscopy（TEM),X-ray diffraction（XRD),X-ray photoelectron spectroscopy（XPS) and Raman spectrometry.Due to the superior electrical conductivity and high electrochemical active sites of HMCS,nicotine was significantly electro-oxidized on the interface of HMCS/SPCE.The proposed sensor provided linear responses upon nicotine in the concentration range of 0-500 μmol/L.The sensitivity was 0.850 mA/(cm2?mmol?L),and the limit of detection was calculated to be 0.058 μmol/L.With a favourable reproducibility and a good stability,the sensor could be used to detect nicotine in cigarette samples accurately.关键词：hollow mesoporous carbon sphere;screen-printed carbon electrodes;nicotine;electrochemical sensor
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发布时间： - 摘要：Two anionic surfactants（SDS and SDBS）, three quaternary ammonium cationic surfactants（CTAB, TTAB and DTAB） and two quaternary ammonium gemini surfactants（12-3-12 and 12-4-12） were used to modified the CPE.Different kinds of surfactants adsorbed on the CPE were studied by using atomic force microscopy, contact angle and the electrochemical behavior of BPA.The results suggested that as the concentration was greater than the CMC, the quaternary ammonium cationic surfactants（e.g.CTAB, TTAB, 12-3-12 and 12-4-12） formed the cylindrical admicelles on the surface of CPE, while DTAB and SDS may be the saturated monolayer adsorption.The electrochemical catalytic mechanism of the admicelle for BPA was investigated, and the results showed that the electrochemical sensitization effect to BPA was mainly due to the admicelle solubilization to the BPA.Furthermore, cation-π effect between cationic surfactants and BPA was the key for BPA solubilization.Therefore, CTAB admicelle modified CPE could be used to detect BPA sensitively.关键词：surfactants;modified electrode;electrochemical catalysis;bisphenol A（BPA）
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发布时间： - 摘要：Matrix effects are universal phenomena in analysis of liquid chromatography-mass spectrometry.By evaluating ‘Ion suppression’,matrix effects of diaveridine,sulfameter,ciprofloxacin,enrofloxacin,chlorotetracycline and tylosin in swine manure detected by ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry(UPLC-ESI-MS/MS)were systematically investigated.The sample was extracted with McIlvaine-Na2EDTA buffer solution,purified and concentrated by a HLB Extraction Cartridge.The residue was dissolved by 0.1% formic acid-methanol(85∶15，by volume).The target compounds were separated on an SB C18 RRHD chromatographic column with 0.1% formic acid-methanol as mobile phase by gradient elution and detected in multiple reaction monitoring(MRM) mode via positive electrospray ionization(ESI+).The result showed that matrix enhancement effects existed in the detection of six antibiotics in swine manure.Furthermore,matrix-matched calibration curve and modified sample treatment could be used to compensate or eliminate the matrix effects in analysis of six antibiotics in swine manure.The study provided a reference for improving the accuracy and precision of the detection result.关键词：matrix effects;ion suppression;ultra performance liquid chromatography-electrospray ionization-tandem mass spectrometry(UPLC-ESI-MS/MS);antibiotics;swine manure
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发布时间： - 摘要：With microplastics as the vector,the enriching capability of microplastics towards lead ions was studied.Firstly,the lead ions absorbed on microplastics were desorbed with 2% nitric acid by ultrasound,and then the lead content was determined by inductively coupled plasma mass spectrometry（ICP-MS） to investigate the adsorption ability.In the present study,the microplastics material,adsorption time,particle size,ion concentration,method selectivity and coexisting ions were investigated to analyze the adsorption characteristics of lead on microplastics.The results showed that different materials of microplastics had different adsorption abilities to lead.Polyvinyl chloride （PVC） and polypropylene （PP） had the best adsorption abilities among all the tested materials,with adsorbances of 1.32 μg/g and 0.63 μg/g,respectively.The adsorbance of microplastics to lead reduced with the increase of the particle size.With the increase of the adsorption time and lead ion concentration,the adsorption efficiency of microplastics to lead increased first and then decreased.The results of coexisting ions experiments indicated that adsorption capacities of different microplastics were influenced by the coexisting ions.There was a competitive adsorption phenomenon when copper and lead coexisted.In this study,the adsorption characteristics of microplastics to lead ion were studied,which could provide a theoretical basis for the further research on enrichment of microplastics to the heavy metals and their environmental behavior in marine environment.关键词：microplastics;polypropylene;adsorption;lead ions;inductively coupled plasma mass spectrometry（ICP-MS）
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发布时间： - 摘要：An inverse opal structural molecular imprinted photonic crystal(MIPC) sensor was established by combining the responsive photonic crystal and molecular imprinting techniques.The 3-D opal structure was obtained by vertical deposition self-assembly of monodisperse silica nanospheres which were prepared by St’ber method.MIPC was obtained after removing SiO2 nanospheres and imprinted molecules.Scanning electron microscope showed that the MIPC possessed a highly ordered 3-D macroporous structure.The recognition for target analytes could be directly transferred into readable optical signals through a fiber optic spectrometer.The factors,such as eluate,pH value,sample matrix and molecular imprinted polymer(MIP) synthesis conditions,were optimized to improve the recognition ability and sensing properties of MIPC sensor.The MIPC sensor showed a good selectivity to ethyl paraben against interferons(2-hydroxy isobutyric acid,benzocaine and procaine) studied.Under the optimized conditions,the shift value of Bragg Diffraction peak of MIPC sensor was linearly related with the concentration of ethyl paraben.The sensor could be re-used with well performance,and the quantitation limit is 83 mg/L.The MIPC sensor could be applied directly and conveniently in monitoring of the target analytes in complex samples with good accuracy and sensitivity,and there is no need for sample processing.So it is suitable for on-site rapid screening and detection.关键词：molecular imprinting;photonic crystal;sensor;ethyl paraben
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发布时间： - 摘要：A method was developed for the determination of chloramphenicol in propolis by high performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS).The flavonoid was removed with NaOH after the dissolution of the sample with methyl tert-butyl ether（MTBE).The solubility of chloramphenicol in MTBE was decreased with n-hexane，and then chloramphenicol was extracted with sodium acetate buffer.After the extraction was transferred to alkaline solution，ethyl acetate was used to extract chloramphenicol.The supernatant was evaporated,and re-dissolved with water for detection.The separation of chloramphenicol was performed on an Atlantis T3 column with methanol and water（65∶35，by volume) as mobile phases，and the detection of chloramphenicol was carried out by tandem mass spectrometry in negative electrospray ionization（ESI-) and multiple reaction monitoring（MRM) mode.The quantification was performed by the internal standard method.The calibration curve showed a good linearity in the range of 0.1-5.0 μg/L.The limits of quantitation（S/N≥10) were 0.3 μg/kg.The recoveries at three spiked levels were in the range of 97.3%-103%with relative standard deviations of 4.8%-6.4%.With the advantages of sensitivity，strong anti-interference capability，good recovery and repeatability，the method was suitable for the monitoring of veterinary residue analysis关键词：propolis;chloramphenicol;high performance liquid chromatography-tandem mass spectrometry （HPLC-MS/MS)
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发布时间： - 摘要：The ionic liquid，1-ethyl-3-carboxymethylimidazolium tetrafluoroborate was synthesized with 1-ethylimidazole based on the single-mode microwave synthesizer.The structure of the product was characterized,and underwent a thermal analysis.Its properties such as viscosity，density，surface tension and electrochemical window were also measured.Meanwhile，the solubility of starch in ionic liquid was investigated.The results showed that the microwave irradiation has the advantages of fastness，short reaction time and mild reaction condition.The yield of the product is 88.23%.Its properties of density，viscosity and surface tension have linear relationships with temperature，respectively.Compared with water，the ionic liquid has a higher solubility for starch soluble，which provides a theoretical basis for the homogeneous derivatization reaction of starch and its derivatives.关键词：focused signal-mode microwave irradiation;ionic liquid;properties;starch;solubility
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发布时间： - 摘要：A simple and rapid method was developed for the determination of disophenol in bulk drug and injection via high performance liquid chromatography（HPLC） with the internal standard method.The sample was prepared with methanol to the test concentration,and filtrated with microfiltration membrane.Separation of analytes was achieved under isocratic elution on a C18 column.The mobile phase consisted of a mixture of 0.02 mol/L potassium dihydrogen phosphate（pH 2.6） and methanol（30∶70）,and was delivered at a flow rate of 1 mL/min.The UV detection was set at 235 nm,and the column temperature was maintained at 30 ℃.The internal standard was nitroclofene and the injection volume was 20 μL.Under the optimum experimental conditions,the proposed HPLC-internal standard method provided a good linearity in the range of 20-120 mg/L for disophenol with the correlation coefficients（r） of 0.999 6.The average recoveries of disophenol at three spiked concentration levels of 64,80 and 96 mg/L were in the range of 90.4%-98.2%,with relative standard deviations（RSDs） of 0.18%-0.72%.The limits of quantitation（LOQs,S/N=10） and limits of detection（LODs,S/N=3） were 1.5 mg/L and 0.15 mg/L,respectively.With good precision,stability and repeatability,the established method was simple,accurate,rapid and reliable for the determination of disophenol in bulk drug and injection.关键词：disophenol;nitroclofene;determination;high performance liquid chromatography（HPLC）;internal standard method
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发布时间： - 摘要：A cell capture scaffold with a structure of Subs-PAA1-SiO2-PAA2-Apt was assembled by using a glass slide as substrate carrier(Subs),polyelectrolyte polyacrylic acid(PAA) as cross-linking agent and flexible body,SiO2 nanoparticles as rigid body,and TD05 aptamer(Apt) as capture ligand of objective cell Ramos.Here there are a small scale and rigid structure(i.e.SiO2 nanoparticle),but also a flexible structure(i.e.polyacrylic acid PAA1 and PAA2).The former increased the roughness of carrier,and the latter could not only immobilized the multi-ligand Apt,but also decreased the steric hindrance from the scaffold itself and the carrier for cell capture.The results indicated that the as-assembled scaffold had a good nanoparticle structure and fusing even disappearing of the nanoparticle structure was not found.For the scaffold,its specific capture was 16 times of the non-specific adsorption,and the captured cell showed a higher purity.Meanwhile the captured cell has also a higher captureefficiency,and the capture cell number was 8.3 times of that of the usual rigid scaffold with one-layer nanoparticle.It was shown that the nanoparticle flexible scaffold with a novel structure was fabricated,which could realize the high purity and the high efficiency for cell capture.关键词：scaffold;cell;capture;nanoparticle;polyelectrolyte
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发布时间： - 摘要：Raman imaging is a kind of modern testing technology based on Raman scattering,which has been widely applied in manufacturing and scientific research.However,due to the fluorescent effect and instruments drift,the baseline shift could easily occur，which has a strong impact on the feature extraction of the Raman signals.Therefore,the baseline correction is necessary and inevitable in the signal processing of Raman spectra.The traditional baseline correction methods can only correct the Raman spectrum one by one,so once a large amount of Raman imaging signals have to be processed,the processing time is too long to accept.In this paper,the baseline correction base on comparison which considers the correlation between the Raman spectra and the same background is proposed to realize the fast baseline correction and improve the processing speed of Raman imaging data.关键词：Raman spectroscopy;baseline correction;comparison;fast imaging
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发布时间： - 摘要：The iron base catalyst residue in Fischer-Tropsch synthetic oil is one of serious issues which has to be paid close attention to in process and quality control.The method for accurate measurement of trace iron in Fischer-Tropsch synthetic oil becomes a crucial concern in process improvement.Several different test methods were compared in present research，and combust ashing samples from Fischer-Tropsch synthetic oil with different boiling points were tested by ICP-AES to determine their total iron trace content.The key procedures for the measurement were optimized.The conditions for Fischer-Tropsch synthetic sample pretreatment were optimized as follows:weighing 5 g of the sample,and ashing it with muffle at 500 ℃ for 1 h.The recovery for iron by this method was larger than 95% with relative standard deviation no more than 5.7%.The limits of detection and quantitation were 0.15 mg/kg and 0.50 mg/kg,respectively.关键词：coal-derived oil;Fischer-Tropsch synthesis;determination of iron content;ICP-AES
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发布时间： - 摘要：Biolayer interferometry is an optical system that monitors interactions between biological materials and detects biological materials rapidly for lable-free.Due to its advantages of real-time,rapidness and low sample consumption,biolayer interferometry has been gradually used for detecting interactions between proteins,peptides,nucleic acids,small molecules,and/or lipids.Furthermore,biolayer interferometry could also provide a solid foundation in rapid detection field because of its low sample consumption and strong specificity.In this article,the principle of biolayer interferometry is discussed,and two major application areas including kinetic analysis and rapid detection are investigated and reviewed.The development trend and future application of biolayer interferometry for measuring biological materials are also prospected.关键词：biolayer interferometry;kinetic analysis;rapid detection;review
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