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Discrimination of individual seed viability by using the oxygen consumption technique and headspace-gas chromatography-ion mobility spectrometry
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作者 TU Ke-ling YIN Yu-lin +2 位作者 YANG Li-ming WANG Jian-hua SUN Qun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第3期727-737,共11页
Identifying and selecting high-quality seeds is crucial for improving crop yield.The purpose of this study was to improve the selection of crop seeds based on separating vital seeds from dead seeds,by predicting the p... Identifying and selecting high-quality seeds is crucial for improving crop yield.The purpose of this study was to improve the selection of crop seeds based on separating vital seeds from dead seeds,by predicting the potential germination ability of each seed,and thus improving seed quality.The methods of oxygen consumption (Q) of seeds and the headspace-gas chromatography-ion mobility spectrometry(HS-GC-IMS) were evaluated for identifying the viability of individual seeds.Firstly,the oxygen consumption technique showed clear differences among the values related to respiratory characteristics for seeds that were either vital or not,and the discrimination ability of final oxygen consumption(Q_(120)) was achieved not only in sweet corn seeds but also in pepper and wheat seeds.Besides,Qtwas established as a new variable to shorten the measuring process in the Q2 (oxygen sensor) procedure,which was significantly related to the viability of individual seeds.To minimize seed damage during measurement,the timing for viability evaluation was pinpointed at the 12,6 and 9 h for pepper,sweet corn,and wheat seeds based on the new variables concerning oxygen consumption (i.e.,Q_(12),Q_(6)and Q_(9),respectively).The accuracies of viability prediction were 91.9,97.7 and 96.2%,respectively.Dead seeds were identified and hence discarded,leading to an enhancement in the quality of the seed lot as indicated by an increase in germination percentage,from 86.6,90.9,and 53.8%to all at 100%.We then used the HS-GC-IMS to determine the viability of individual sweet corn seeds,noting that corn seed has a heavier weight so the volatile gas components are more likely to be detected.A total of 48 chromatographic peaks were identified,among which 38 target compounds were characterized,including alcohols,aldehydes,acids and esters.However,there were no significant differences between the vital and dead seeds,due to the trace amount volatile composition differences among the individual seeds.Furthermore,a PCA based on the signal intensities of the target volatile compounds obtained was found to lose its effectiveness,as it was unable to distinguish those two types of sweet corn seeds.These strategies can provide a reference for the rapid detection of single seed viability. 展开更多
关键词 headspace-gas chromatography-ion mobility spectrometry oxygen consumption seed respiration sweet corn TOMATO wheat
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Determination of Benzo[a]pyrene in Edible Oil by High Performance Liquid Chromatography-Fluorescence Detector (HPLC-FL)
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作者 Guixia YANG Jie LIU +3 位作者 Xiujuan WANG Fenglan ZHANG Kun XIN Chunli KONG 《Agricultural Biotechnology》 2024年第2期8-9,19,共3页
In this study, an optimized high performance liquid chromatography-fluorescence detector (HPLC-FL) method for the determination of benzo[a]pyrene in edible oil was established. HPLC was performed with Thermo Fisher Sc... In this study, an optimized high performance liquid chromatography-fluorescence detector (HPLC-FL) method for the determination of benzo[a]pyrene in edible oil was established. HPLC was performed with Thermo Fisher Scientific C18 column (250 mm×4.6 mm, 5 μm) as the chromatographic column and acetonitrile and water as the mobile phase, and the excitation wavelength and emission wavelength of fluorescence detector were 286 and 430 nm, respectively. The response was high, and the linear range was 0.5-10.0 ng/ml. The lowest limit of detection was 0.11 ng/ml, and the average recovery was 92.5%. This method is suitable for quantitative analysis of benzo[a]pyrene content in edible oil. 展开更多
关键词 BENZO[A]PYRENE High performance liquid chromatography Fluorescence detector
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Efficient and selective extraction of uranium from seawater based on a novel pulsed liquid chromatography radionuclide separation method 被引量:2
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作者 Jian‑Hua Ye Tao Yu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第2期13-27,共15页
The novel pulsed liquid chromatography radionuclide separation method presented here provides a new and promising strategy for the extraction of uranium from seawater.In this study,a new chromatographic separation met... The novel pulsed liquid chromatography radionuclide separation method presented here provides a new and promising strategy for the extraction of uranium from seawater.In this study,a new chromatographic separation method was proposed,and a pulsed nuclide automated separation device was developed,alongside a new chromatographic column.The length of this chromatographic column was 10 m,with an internal warp of 3 mm and a packing size of 1 mm,while the total separation units of the column reached 12,250.The most favorable conditions for the separation of nuclides were then obtained through optimizing the separation conditions of the device:Sample pH in the column=2,sample injection flow rate=5.698 mL/min,chromatographic column heating temperature=60℃.Separation experiments were also carried out for uranium,europium,and sodium ions in mixed solutions;uranium and sodium ions in water samples from the Ganjiang River;and uranium,sodium,and magnesium ions from seawater samples.The separation factors between the different nuclei were then calculated based on the experimental data,and a formula for the separation level was derived.The experimental results showed that the separation factor in the mixed solution of uranium and europium(1:1)was 1.088,while achieving the initial separation of uranium and europium theoretically required a 47-stage separation.Considering the separation factor of 1.50for the uranium and sodium ions in water samples from the Ganjiang River,achieving the initial separation of uranium and sodium ions would have theoretically required at least a 21-stage separation.Furthermore,for the seawater sample separation experiments,the separation factor of uranium and sodium ions was 1.2885;therefore,more than 28 stages of sample separation would be required to achieve uranium extraction from seawater.The novel pulsed liquid chromatography method proposed in this study was innovative in terms of uranium separation and enrichment,while expanding the possibilities of extracting uranium from seawater through chromatography. 展开更多
关键词 Pulsed liquid chromatography Nuclide separation Seawater uranium extraction Uranium enrichment
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Determination of Organic Acids in Root Exudates by High Performance Liquid Chromatography: I.Development and Assesment of Chromatographic Conditions 被引量:4
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作者 SHENJIANBO ZHANGFUSUO 《Pedosphere》 SCIE CAS CSCD 1998年第2期97-104,共8页
Plantrootsexudeavarietyoforganiccompoundstotherhizosphere.Theamountofrootexudates,expresedasafractionoftheto... Plantrootsexudeavarietyoforganiccompoundstotherhizosphere.Theamountofrootexudates,expresedasafractionofthetotaldrymaterproduc... 展开更多
关键词 高效液相色谱法 有机酸 大豆 根围 根部分泌液 测定
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Separation and analysis of six fractions in low temperature coal tar by column chromatography
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作者 Shuangtai Liu Lei He +5 位作者 Qiuxiang Yao Xi Li Linyang Wang Jing Wang Ming Sun Xiaoxun Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期256-265,共10页
The low temperature coal tar(CT)is taken as the raw material,and the extraction and column chromatography are used for detailed and accurate characterization in this paper.The n-heptane soluble fraction(CT-HS)and inso... The low temperature coal tar(CT)is taken as the raw material,and the extraction and column chromatography are used for detailed and accurate characterization in this paper.The n-heptane soluble fraction(CT-HS)and insoluble fraction(CT-HI)were obtained by n-heptane Soxhlet extraction.The extraction rate of CT-HS reached 92.79%(mass),which indicated that there are few heavy compounds in it.Further,different solvents(methylbenzene,benzene,ethyl acetate,methylbenzene-ethanol)were used to elute CT-HS by chromatographic column to obtain five fractions(saturates,aromatics,heteroatoms,phenolics and resins,named CT-SA,CT-AR,CT-HE,CT-PH,CT-RE,respectively).The yields of CTSA,CT-AR,CT-HE,CT-PH,CT-RE are 42.12%,10.43%,2.19%,9.50%and 6.63%(mass),respectively.Gas chromatography-mass spectrometry analysis of eluting components show that alkanes are the main components in CT,followed by polycyclic aromatics,and the corresponding fractions are CT-SA and CT-AR,respectively.The relative content of aliphatics in CT-SA is 76.93%,and the relative content of aromatics in CT-AR is 75.05%.This separation technology effectively separates and enriches different components in CT,and the activation energy required for the pyrolysis process of a single eluting fraction is lower than that of CT,which is expected to provide an important reference for the separation,analysis and conversion of complex oil products such as coal-oil co-processing products,coal tar and other complex heavy carbon oil products. 展开更多
关键词 Low temperature coal tar Extractive separation Column chromatography isolation chromatography/mass spectrometry
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A High-Performance Liquid Chromatography Method for the Simultaneous Determination of Five Index Components in Danhong Injection
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作者 Yun An Tian Tian +2 位作者 Qinglin Wang Xingchu Gong Chenchen Zhang 《American Journal of Analytical Chemistry》 2023年第11期481-492,共12页
The purpose of this study was to establish a high-performance liquid chromatography (HPLC) method for the simultaneous determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, a... The purpose of this study was to establish a high-performance liquid chromatography (HPLC) method for the simultaneous determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, and 4-coumaric acid in Danhong injection. The chromatographic method employed was as follows: the column was a Welch Ultimate XB-C18 column (250 mm × 4.6 mm, 10 μm), the mobile phase was a gradient elution of 0.4% formic acid aqueous solution (A) and acetonitrile (B), the detection wavelengths were 280 nm for sodium danshensu, protocatechuic aldehyde, and salvianolic acid B and 326 nm for 4-coumaric acid and rosmarinic acid, the sample volume was 10 μL, the flow rate was 1.0 mL/min, and the column temperature was 35°C. This method can realize the separation and determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, and 4-coumaric acid within 50 minutes. The linear relationships of the five peak areas and their concentrations are good (R<sup>2</sup>> 0.9997). The precision RSD values are all less than 1.0%. The reproducibility RSD values are all less than 1.3%. The stability RSD values are all less than 2.2%. The recovery values ranged from 92.4% to 99.4%. This method is simple, accurate, and reproducible. It can be used for the determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, and 4-coumaric acid in Danhong injection. 展开更多
关键词 Danhong Injection High Performance Liquid chromatography Phenolic Acid FLAVONOIDS
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Determination of Voriconazole in Human Plasma by Liquid Chromatography Tandem Mass Spectrometry: Application in Therapeutic Drug Monitoring
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作者 Waleed Alhussaini Ezzeldeen Ghanem +4 位作者 Magd Alsahly Amani Kurdi Eman Alharbi Imadul Islam Majed Aljeraisy 《American Journal of Analytical Chemistry》 2023年第9期378-389,共12页
A sensitive, accurate and robust Liquid Chromatography Tandem Mass Spectrometry method has been developed and validated to measure voriconazole trough levels in human plasma. The plasma samples were mixed with flucona... A sensitive, accurate and robust Liquid Chromatography Tandem Mass Spectrometry method has been developed and validated to measure voriconazole trough levels in human plasma. The plasma samples were mixed with fluconazole as an Internal Standard and directed to protein precipitation and drug extraction. An aliquot of 1 μl was injected into the chromatographic system and separated by the Acquity BEH C18 column at a flow rate of 0.30 ml/min in a gradient mobile phase consisting of acetonitrile, Ultrapure water (UPW), methanol and formic acid. Voriconazole was detected by a Triple Quadrupole Detector (TQD) operating on Multiple Reaction Monitoring (MRM) and a positive ion mode Electrospray ionization (ESI) Q1 mass: 350.1 m/z, Q3 mass: 281.1 m/z. Method linearity of the calibration curve (0.10 - 8.00 μg/ml) indicated a correlation coefficient r ≥ 0.99. The intra and inter-assay accuracy was within 85% - 115% and the intra and inter-assay precision was ≤5.76%. Voriconazole recovery percentage was between 97.69 - 119.62%. The method was successively applied in routine voriconazole TDM. 展开更多
关键词 VORICONAZOLE Human Plasma Liquid chromatography Tandem Mass Spectrometry Therapeutic Drug Monitoring
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Phytochemical Screening and Chromatographic Purification of Bauhunia semibifida ROXB Hexane-Dichloromethane Leaf Extract
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作者 Ikenna Obiora Alaekwe Vincent Ishmel Egbulefu Ajiwe Chinedu Chris Aguoma 《Journal of Materials Science and Chemical Engineering》 2023年第7期14-19,共6页
Bauhunia semibifida is among the several plants that have been studied for their medicinal properties. Bauhunia is native to India. However, some species have been found in Africa. It has several important uses, such ... Bauhunia semibifida is among the several plants that have been studied for their medicinal properties. Bauhunia is native to India. However, some species have been found in Africa. It has several important uses, such as anti-bacterial, anti-inflammatory and anti-cancerous. This study is aimed primarily at carrying out a preliminary phytochemical screening to ascertain the classes of bioactive compounds present in Bauhunia semibifida and ascertain the solvent system(s) for their separation. Several solvents were used for the extraction as well as in the chromatographic profiling of all the products of extraction. Thin layer chromatography was performed on silica gel-coated glass plates using several mobile phase protocols (Hexane: Ethylacetate, Dichloromethane (DCM): Methanol). Further purification of the extracts was done using classical column (CcSiO<sub>2</sub>) and gel filtration chromatography. TLC profiling of DCM and Hexane extracts shows the same Rf values of less than 1 and are thus combined to give the Hexane/DCM extract, which gave two compounds following isocratic elution from column chromatography. Phytochemical screening of the extract showed the presence of Tannins, Cardiac glycosides, Alkaloids, Flavonoids and Phenolic compounds. Hexane/DCM extract thus contains phytocompounds which can further be studied. 展开更多
关键词 Bauhinia semibifida Phytochemical Screening HERBS Medicinal Plants chromatography
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Preparation Process and Thin Layer Chromatography Identification of Wufang Babu Poultice
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作者 Junjun LIU Luyao XIE +2 位作者 Chuhui ZHOU Zhengteng YANG Xiongbin GUI 《Medicinal Plant》 CAS 2023年第4期58-61,共4页
[Objectives] To establish the process flow of preparation of Wufang Babu Poultice and the identification method of thin layer chromatography (TLC). [Methods] For the forming process of Wufang Babu Poultice, the prepar... [Objectives] To establish the process flow of preparation of Wufang Babu Poultice and the identification method of thin layer chromatography (TLC). [Methods] For the forming process of Wufang Babu Poultice, the preparation method of mixed pharmaceutical powder with suitable pharmaceutical excipients was adopted. Qualitative identification of medicinal materials in Wufang Babu Poultice (Strychni Semen, Rhei Radix Et Rhizoma, Dipsaci Radix, and Angelicae Sinensis Radix) was carried out by TLC. [Results] Mixed pharmaceutical powder mixed with glycerol, gelatin and other pharmaceutical excipients can be prepared for forming. The test solution chromatography of each medicinal material (Strychni Semen, Rhei Radix et Rhizoma, Dipsaci Radix, Angelicae Sinensis Radix) showed pigment spots of the same color at the same position as its corresponding control medicinal materials and reference chromatography, and the display was clear. [Conclusions] The preparation process is simple and feasible, and can be used as the forming process of Wufang Babu Poultice. The TLC determination method is simple to operate, has good specificity, and has no effect on negative results, and can be used for identification of Wufang Babu Poultice. 展开更多
关键词 Wufang Babu Poultice Preparation process Thin layer chromatography(TLC)
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Ash Detection of Coal Slime Flotation Tailings Based on Chromatographic Filter Paper Sampling and Multi-Scale Residual Network
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作者 Wenbo Zhu Neng Liu +4 位作者 Zhengjun Zhu Haibing Li Weijie Fu Zhongbo Zhang Xinghao Zhang 《Intelligent Automation & Soft Computing》 2023年第12期259-273,共15页
The detection of ash content in coal slime flotation tailings using deep learning can be hindered by various factors such as foam,impurities,and changing lighting conditions that disrupt the collection of tailings ima... The detection of ash content in coal slime flotation tailings using deep learning can be hindered by various factors such as foam,impurities,and changing lighting conditions that disrupt the collection of tailings images.To address this challenge,we present a method for ash content detection in coal slime flotation tailings.This method utilizes chromatographic filter paper sampling and a multi-scale residual network,which we refer to as MRCN.Initially,tailings are sampled using chromatographic filter paper to obtain static tailings images,effectively isolating interference factors at the flotation site.Subsequently,the MRCN,consisting of a multi-scale residual network,is employed to extract image features and compute ash content.Within the MRCN structure,tailings images undergo convolution operations through two parallel branches that utilize convolution kernels of different sizes,enabling the extraction of image features at various scales and capturing a more comprehensive representation of the ash content information.Furthermore,a channel attention mechanism is integrated to enhance the performance of the model.The combination of the multi-scale residual structure and the channel attention mechanism within MRCN results in robust capabilities for image feature extraction and ash content detection.Comparative experiments demonstrate that this proposed approach,based on chromatographic filter paper sampling and the multi-scale residual network,exhibits significantly superior performance in the detection of ash content in coal slime flotation tailings. 展开更多
关键词 Coal slime flotation ash detection chromatography filter paper multi-scale residual network
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离子色谱法检测水质中微量甘油
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作者 王芳 徐晶晶 +1 位作者 黄杰军 徐林 《现代化工》 CAS CSCD 北大核心 2024年第2期252-255,共4页
建立了离子色谱法测定水质中微量甘油的方法。在酸性条件下,使用高碘酸钠将甘油定量氧化成甲酸,再通过离子色谱法定量检测甲酸根含量,从而折算得到甘油准确含量。甘油衍生化样品用20 mmol/L KOH洗脱液淋洗,淋洗流量为1.0 mL/min, Dionex... 建立了离子色谱法测定水质中微量甘油的方法。在酸性条件下,使用高碘酸钠将甘油定量氧化成甲酸,再通过离子色谱法定量检测甲酸根含量,从而折算得到甘油准确含量。甘油衍生化样品用20 mmol/L KOH洗脱液淋洗,淋洗流量为1.0 mL/min, Dionex IonPac AS15阴离子交换色谱柱分离,抑制型电导检测器检测。衍生化后的甲酸根检出限为0.015 mg/L,对水质样品衍生化后的甲酸根离子在0.5、1.0、2.0、3.0 mg/L加标水平的回收率为96.26%~99.68%,该方法的相对标准偏差为0.39%。结果表明,该方法前处理条件温和、反应速度快、副产物少、灵敏度高、准确度高、重复性好,适用于水质中微量甘油含量的检测。 展开更多
关键词 离子色谱法 甘油 衍生化 甲酸根
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采用气相色谱-质谱指纹图谱鉴定铁木豆属木材
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作者 吴静霞 顾钰华 +3 位作者 姚晨岚 肖湾 龚青 李倩 《化学分析计量》 CAS 2024年第2期82-86,92,共6页
采用气相色谱-质谱指纹图谱分别鉴定平萼铁木豆、葱叶状铁木豆和马达加斯加铁木豆属木材。以二氯甲烷提取样品中的特定化合物,采用气相色谱-质谱法分析提取物,建立目标物色谱图。平萼铁木豆在保留时间25.1 min的最强吸收峰和22.3、22.6... 采用气相色谱-质谱指纹图谱分别鉴定平萼铁木豆、葱叶状铁木豆和马达加斯加铁木豆属木材。以二氯甲烷提取样品中的特定化合物,采用气相色谱-质谱法分析提取物,建立目标物色谱图。平萼铁木豆在保留时间25.1 min的最强吸收峰和22.3、22.6及23.4 min的次强吸收峰可作为平萼铁木豆的特征图谱,与其他两种铁木豆相区分。葱叶状铁木豆和马达加斯加铁木豆的最强吸收峰色谱保留时间均为16.3 min,葱叶状铁木豆的次强吸收峰色谱保留时间为18.5 min,另外还在色谱保留时间分别为19.4、19.8、24.3 min处有吸收峰,而马达加斯加铁木豆除在色谱保留时间17.7 min处有次强吸收峰外,还在色谱保留时间为23.4 min时有吸收峰。气相色谱-质谱法可用于平萼铁木豆、葱叶状铁木豆和马达加斯加铁木豆三类木材的鉴别。 展开更多
关键词 木材 气相色谱-质谱联用仪 铁木豆
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益肝片的质量标准研究
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作者 刘雪萍 邓书武 蒋伟哲 《广西医科大学学报》 CAS 2024年第1期124-130,共7页
目的:提升益肝片的质量标准。方法:采用薄层色谱法(TLC)鉴别益肝片中的板蓝根、虎杖;采用高效液相色谱法(HPLC)对益肝片中的(R,S)-告依春和大黄素进行含量测定。结果:通过TLC鉴别板蓝根、虎杖,相应斑点清晰、分离度好,阴性无干扰。(R,S)... 目的:提升益肝片的质量标准。方法:采用薄层色谱法(TLC)鉴别益肝片中的板蓝根、虎杖;采用高效液相色谱法(HPLC)对益肝片中的(R,S)-告依春和大黄素进行含量测定。结果:通过TLC鉴别板蓝根、虎杖,相应斑点清晰、分离度好,阴性无干扰。(R,S)-告依春在进样量0.03~0.15μg范围内与峰面积线性关系良好(r=0.9998),平均加样回收率为97.05%,大黄素在进样量0.0495~0.297μg范围内与峰面积线性关系良好(r=1.0000),平均加样回收率为99.24%。结论:本质量标准能有效鉴别益肝片中的板蓝根、虎杖,也能有效测定(R,S)-告依春和大黄素的含量,且该法简便、可靠、重复性好,可用于益肝片的质量控制。 展开更多
关键词 益肝片 质量标准 薄层色谱法 高效液相色谱法
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烫疗药提取工艺及质量标准提升研究
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作者 陈锋 黄蓓 +3 位作者 韦金彩 莫海涛 覃翔 梁国成 《中医药导报》 2024年第1期42-45,54,共5页
目的:优选烫疗药浸渍提取工艺,提升烫疗药质量标准。方法:以浸渍溶剂浓度、浸渍时间、浸渍温度、原料粉碎度为考察因素,以川续断皂苷Ⅵ含量和醇溶性浸出物为评价指标,通过L9(34)正交试验优选烫疗药最佳浸渍提取工艺;采用薄层色谱法(TLC... 目的:优选烫疗药浸渍提取工艺,提升烫疗药质量标准。方法:以浸渍溶剂浓度、浸渍时间、浸渍温度、原料粉碎度为考察因素,以川续断皂苷Ⅵ含量和醇溶性浸出物为评价指标,通过L9(34)正交试验优选烫疗药最佳浸渍提取工艺;采用薄层色谱法(TLC)对烫疗药中防风、大黄、姜黄进行定性鉴别;采用高效液相色谱(HPLC)法对川续断皂苷Ⅵ进行定量测定。结果:筛选的最佳浸提工艺为将烫疗药处方饮片粉碎成细粉碎度,以50%的乙醇为溶剂,室温下浸渍5 d;川续断皂苷Ⅵ在19.30715~154.45720μg/mL范围内呈良好的线性关系(r=0.9999),平均加样回收率为102.37%,RSD=1.48%(n=6);定性鉴别中防风、大黄、姜黄斑点清晰,分离效果较好,具有鉴别特征。结论:优选的浸提工艺稳定可行;所建立的质量控制方法稳定性及重现性良好,专属性较强,可作为烫疗药的质量控制依据。 展开更多
关键词 烫疗药 正交试验 高效液相色谱 薄层色谱
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在线燃烧离子色谱法测定环氧树脂中的氯和溴
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作者 巢静波 史乃捷 +5 位作者 王海峰 周希蕊 房叶天 陈艳 许峰 朱天一 《环境化学》 CAS CSCD 北大核心 2024年第1期152-159,共8页
建立了在线燃烧离子色谱同时测定环氧树脂中氯和溴的分析方法.采用高温裂解炉与离子色谱的在线联用装置,通过对样品进行高温燃烧裂解和气化,以100 mg·L^(-1)过氧化氢为吸收液,将产生的卤化氢气体吸收并转化为无机阴离子,离子色谱... 建立了在线燃烧离子色谱同时测定环氧树脂中氯和溴的分析方法.采用高温裂解炉与离子色谱的在线联用装置,通过对样品进行高温燃烧裂解和气化,以100 mg·L^(-1)过氧化氢为吸收液,将产生的卤化氢气体吸收并转化为无机阴离子,离子色谱法进行样品的测定,以氯和溴的峰面积外标法进行定量.对影响燃烧效果和测定结果准确度的因素如燃烧时间、燃烧温度、吸收液体积、称样量、氧气和氩气流速等条件进行了选择优化.在(0.10—2.50)mg·L^(-1)和(0.02—0.50)mg·L^(-1)范围内,氯和溴离子的线性相关系数(r^(2))大于0.999,该方法对于氯和溴的定量下限分别为0.55 mg·kg^(-1)和2.60 mg·kg^(-1).采用建立的方法分别对环氧树脂和EC680k低密度聚乙烯标准物质中的氯和溴进行测定,并与传统的氧弹燃烧-离子色谱法进行了比较.结果表明:在线燃烧离子色谱法对于环氧树脂中氯和溴测定结果的相对标准偏差分别为1.28%和2.29%,测定值与氧弹燃烧-离子色谱法基本一致,EC680k的测定结果与标准值符合,证明该方法具有良好的准确度和精密度.该方法准确度和灵敏度高、重复性较好,能够满足批量树脂类样品中氯和溴的含量筛查和多批次产品的质量控制. 展开更多
关键词 在线燃烧离子色谱 环氧树脂
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离子色谱法同时测定脱硫液中8种有机胺类物质
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作者 高立红 姜振邦 +1 位作者 郑洪国 厉文辉 《色谱》 CAS CSCD 北大核心 2024年第5期452-457,共6页
有机胺脱硫工艺因高效、经济等优点,应用越来越广泛。不同配比的有机胺对二氧化硫脱除效果不同。因此,对脱硫液中的不同有机胺成分进行准确测定具有重要意义。离子色谱法检测有机胺不需要衍生步骤,前处理简单,并且可同时测定多种有机胺... 有机胺脱硫工艺因高效、经济等优点,应用越来越广泛。不同配比的有机胺对二氧化硫脱除效果不同。因此,对脱硫液中的不同有机胺成分进行准确测定具有重要意义。离子色谱法检测有机胺不需要衍生步骤,前处理简单,并且可同时测定多种有机胺。本研究采用离子色谱法同时测定乙醇胺(MEA)、二乙基乙醇胺(DEEA)、N-甲基二乙醇胺(MDEA)、2-氨基-2-甲基-1-丙醇(AMP)、羟乙基乙二胺(AEEA)、哌嗪(PZ)、N-羟乙基哌嗪(HEPZ)、二乙烯三胺(DETA)等8种有机胺。实验对比不同型号色谱柱、淋洗液和柱温条件对8种有机胺的分离效果,最终采用IonPac CS17色谱柱,柱温35℃,甲基磺酸(MSA)水溶液梯度淋洗,抑制电导法进行测定。脱硫液样品采用超纯水稀释,过0.22μm尼龙微孔滤膜和OnGuardⅡRP柱后进样分析,样品前处理简便。8种有机胺在一定范围内具有良好的线性关系,判定系数R~2≥0.998 0。以信噪比(S/N)=3时对应的有机胺质量浓度为检出限(LOD),以S/N=10时对应的有机胺质量浓度为定量限(LOQ)。在进样量1.0μL时,LOD即可达到0.02~0.08 mg/L, LOQ为0.07~0.27 mg/L。实际样品的加标回收率为93.0%~111%,相对标准偏差(RSD,n=5)为0.31%~1.2%,说明方法具有良好的准确性和精密度,适用于脱硫液中多种有机胺的测定。 展开更多
关键词 离子色谱 有机胺类物质 脱硫液
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基于HS-GC-IMS和HS-SPME-GC-MS的蛋白酶对豆粕挥发性风味的影响分析
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作者 齐宝坤 刘雨雯 +3 位作者 姚玉雪 吴思雨 孙树坤 陈昊 《农业机械学报》 EI CAS CSCD 北大核心 2024年第4期352-367,410,共17页
为研究不同蛋白酶酶解对豆粕挥发性风味成分的影响,选用4种蛋白酶(碱性蛋白酶、中性蛋白酶、木瓜蛋白酶、风味蛋白酶)对豆粕进行酶解,采用顶空-气相色谱-离子迁移谱(Headspace-gas chromatography-ion mobility spectroscopy,HS-GC-IMS... 为研究不同蛋白酶酶解对豆粕挥发性风味成分的影响,选用4种蛋白酶(碱性蛋白酶、中性蛋白酶、木瓜蛋白酶、风味蛋白酶)对豆粕进行酶解,采用顶空-气相色谱-离子迁移谱(Headspace-gas chromatography-ion mobility spectroscopy,HS-GC-IMS)和顶空固相微萃取-气相色谱-质谱(Headspace solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)联用技术分析不同豆粕酶解物(Soybean meal hydrolysates,SMH)的挥发性风味成分,并结合主成分分析(Principal component analysis,PCA)、热图聚类和正交偏最小二乘判别法(Orthogonal partial least squares-discriminant analysis,OPLS-DA)对不同SMH进行分析。结果表明:碱性蛋白酶、中性蛋白酶、木瓜蛋白酶和风味蛋白酶酶解豆粕的挥发性风味成分存在较大差异。HS-GC-IMS鉴定出84种挥发性成分,筛选得到33种差异风味物质,发现酶解后酮类物质显著降低而醛类、醇类和酯类物质含量明显增加。PCA结果表明不同SMH之间的风味存在显著差异。最终通过OPLS-DA筛选出贡献较大的挥发性化合物,同时构建出可靠的用以鉴别SMH的模型。HS-SPME-GC-MS检测出103种差异风味物质,可用于区分不同SMH,被检出的挥发性组分中醛类、醇类和酮类等化合物为SMH风味的形成做出主要贡献,明晰了部分风味化合物形成的原因。PCA和聚类热图结果表明不同蛋白酶酶解对豆粕的挥发性风味物质的种类和含量有显著影响,其中,风味蛋白酶和木瓜蛋白酶对豆粕的风味改善最为显著。 展开更多
关键词 豆粕 酶解 顶空-气相色谱-离子迁移谱 顶空固相微萃取-气相色谱-质谱
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HPLC及LC-MS测定榛子中氯吡苯脲和多菌灵残留
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作者 桑育黎 王沛 +2 位作者 郝延军 李楠楠 戚建忠 《辽宁大学学报(自然科学版)》 CAS 2024年第1期8-15,共8页
本文采用高效液相色谱法(HPLC)和液相色谱-质谱法(LC-MS)对干果榛子中氯吡苯脲和多菌灵残留量进行含量测定.HPLC和LC-MS均使用C18色谱柱,含量测定采取等度洗脱,流动相:甲醇-水(55∶45,体积比);体积流量:1.0 mL·min-1;测定波长:260 ... 本文采用高效液相色谱法(HPLC)和液相色谱-质谱法(LC-MS)对干果榛子中氯吡苯脲和多菌灵残留量进行含量测定.HPLC和LC-MS均使用C18色谱柱,含量测定采取等度洗脱,流动相:甲醇-水(55∶45,体积比);体积流量:1.0 mL·min-1;测定波长:260 nm;柱温:30℃.LC-MS采取电喷雾离子源,梯度洗脱,体积流量:0.6 mL·min-1,柱温:30℃.结果表明,榛子中氯吡苯脲与多菌灵存在残留,氯吡苯脲质量浓度在1.00~10.00μg·mL-1范围内线性关系良好,加样回收率在95.58%~100.58%;多菌灵质量浓度在1.005~15.075μg·mL-1范围内具有良好的线性关系,加样回收率在95.61%~104.39%.实验证明,HPLC与LC-MS相结合的方法具有操作简便、灵敏度高、检出限低等优点,能有效地检测到榛子样品中膨大剂氯吡苯脲及杀菌剂多菌灵的残留,并确定其残留量,线性关系和回收率结果均令人满意.根据被检测的8批样品中氯吡苯脲和多菌灵两项农药残留量推断,作为一般干果食用榛子是安全的. 展开更多
关键词 榛子 氯吡苯脲 多菌灵 高效液相色谱法(HPLC) 液相色谱-质谱法(LC-MS)
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烟草中甲霜灵的手性分离方法差异研究
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作者 王维刚 陈志燕 +4 位作者 唐石云 周芸 朱丽 洪玮 杨飞 《化学试剂》 CAS 2024年第5期87-92,共6页
对比反相液相色谱-串联质谱(RPLC-MS/MS)和超临界流体色谱-串联质谱(SFC-MS/MS)手性分离烟草中甲霜灵的差异。烟草样品经乙腈提取、盐析分层、快速滤过型净化(multi-Plug Filtration Cleanup,m-PFC)柱净化后,分别采用RPLC-MS/MS和SFC-MS... 对比反相液相色谱-串联质谱(RPLC-MS/MS)和超临界流体色谱-串联质谱(SFC-MS/MS)手性分离烟草中甲霜灵的差异。烟草样品经乙腈提取、盐析分层、快速滤过型净化(multi-Plug Filtration Cleanup,m-PFC)柱净化后,分别采用RPLC-MS/MS和SFC-MS/MS进行手性分离。从多个性能参数(分离效率、线性、选择性、回收率、重复性、灵敏度、基质效应等)对两种方法进行了全面比较。采用不同的分离方法,在10~500 ng/mL范围内,甲霜灵的不同异构体均可呈现良好的线性关系(R^(2)≥0.9993)。在各异构体加标浓度为0.1、0.5、2.0 mg/kg水平下,采用不同的分离方法均可获得满意的回收率(88.7%~96.2%)和良好的重复性(RSD<7.0%)。结果表明:RPLC-MS/MS和SFC-MS/MS具有互补性,均适用于手性分离和测定烟草基质中的甲霜灵。 展开更多
关键词 反相液相色谱-串联质谱 超临界流体色谱-串联质谱 快速滤过型净化 烟草 甲霜灵 手性分离
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气相色谱-三重四极杆质谱法测定黄芪中42种农药残留
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作者 田丽 胡佳薇 +1 位作者 尹丹阳 王敏娟 《食品安全质量检测学报》 CAS 2024年第7期225-233,共9页
目的建立气相色谱-三重四极杆质谱法测定黄芪中42种农药的方法。方法黄芪中的多组分农药采用乙腈提取,上清液经N-丙基乙二胺、十八烷基硅烷键合硅胶、硅胶净化,采用程序升温进样口上机测定,基质匹配曲线外标法定量。结果42种农药在0.01~... 目的建立气相色谱-三重四极杆质谱法测定黄芪中42种农药的方法。方法黄芪中的多组分农药采用乙腈提取,上清液经N-丙基乙二胺、十八烷基硅烷键合硅胶、硅胶净化,采用程序升温进样口上机测定,基质匹配曲线外标法定量。结果42种农药在0.01~1.00μg/mL范围内线性关系良好,相关系数为0.9954~0.9999,在空白基质中添加低(0.02 mg/kg)、中(0.40 mg/kg)、高(2.00 mg/kg)3个不同浓度的混合标准品各6份,加标回收率为72.5%~109.3%,相对标准偏差为1.25%~6.07%,检出限为0.002~0.010mg/kg,定量限为0.005~0.030 mg/kg。在100批次黄芪样本中检出6种农药,分别是α-硫丹、对硫磷、甲基对硫磷、硫环磷、氯氰菊酯、氰戊菊酯,样品检出率6.0%,样品超标率1.0%,超标农药为氯氰菊酯。结论本方法灵敏度高、准确性好,适用于黄芪中42种农药的同时测定。 展开更多
关键词 气相色谱-三重四极杆质谱法 农药残留 黄芪
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