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Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator
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作者 Yang Zhang Sheng-Quan Yan +36 位作者 Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning Li Xiao-Fei Wang Jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li Jian Zheng Qi-Wen Fan Yun-Ju Li You-Bao Wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-Hao Li Jun-Wen Tian Jiang-Lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao Tian Jin-Long Ma Yi-Hui Liu Jing-Yu Dong Run-Long Liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing Guo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期136-143,共8页
The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides... The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated. 展开更多
关键词 Accelerator mass spectrometry Wien filter Isobar separation SUPERNOVAE Chang'e-5 lunar samples
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Determination of Ten Kinds of Alpha-2 Agonists Residues in Animal Derived Food by UHPLC-Triple Quadrupole/Composite Linear Ion Trap Mass Spectrometry
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作者 Fang LI Xuemei LI +3 位作者 Xiangang LI Sining LIU Sha LIU Ying WANG 《Plant Diseases and Pests》 2024年第1期28-32,共5页
[Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived f... [Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived food.[Methods]The samples were extracted with sodium carbonate buffer solution and ethyl acetate,and analyzed by mass spectrometry after solid phase extraction and high performance liquid chromatography separation.[Results]Ten kinds ofα2-receptor agonists showed a good linear relationship in the range of 1-100μg/mL,with the average recovery of over 69%and the relative standard deviation less than 8.32%.The detection limit of 10 kinds of α_(2)-receptor agonists was up to 1μg/kg.[Conclusions]The method has good selectivity and strong anti-interference ability,and can meet the requirements of 10 kinds ofα2-receptor agonists residues in animal derived food. 展开更多
关键词 Animal derived food α_(2)-receptor agonist Solid-phase extraction Ultra-high performance liquid phase-triple quadrupole/linear ion trap composite mass spectrometry
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Research on the Upper Limit of Accuracy for Predicting Theoretical Tandem Mass Spectrometry
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作者 Changjiu He Xiaoyu Wang +1 位作者 Mingming Lyu Xinye Bian 《Journal of Computer and Communications》 2024年第3期184-195,共12页
In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy... In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy of current methods approaches this limit, further exploration of new prediction techniques may become redundant. Conversely, a need for more precise prediction methods or models may be indicated. In this study, we have experimentally analyzed the limits of accuracy at different numbers of ions and parameters using repeated spectral pairs and integrating various similarity metrics. Results show significant achievements in accuracy for backbone ion methods with room for improvement. In contrast, full-spectrum prediction methods exhibit greater potential relative to the theoretical accuracy limit. Additionally, findings highlight the significant impact of normalized collision energy and instrument type on prediction accuracy, underscoring the importance of considering these factors in future theoretical tandem mass spectrometry predictions. 展开更多
关键词 Tandem mass spectrometry Spectral Prediction Theoretical Limit
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Psychological Consequences of a Mass Attack Following Multiple Gunshots and Explosions among Victims in a State in Southwest Nigeria
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作者 Adewale Moses Adejugbagbe Dele David Omoniyi +4 位作者 Akinola Ayoola Fatiregun Modupeola Oluwakemi Dosumu Ngozi Onyejiaka Banji Awolowo Ajaka Stephen Fagbemi 《Open Journal of Epidemiology》 2024年第1期90-109,共20页
Introduction: On the 5<sup>th</sup> of June 2022, an incident of a mass attack following multiple gunshots and explosions occurred in a community in Ondo State Nigeria. This study aims to assess the mental... Introduction: On the 5<sup>th</sup> of June 2022, an incident of a mass attack following multiple gunshots and explosions occurred in a community in Ondo State Nigeria. This study aims to assess the mental health status of victims of the mass attack to guide further interventions among them. Methods: A cross-sectional study was conducted among victims of a mass attack in Owo community, Ondo State. A total of 209 affected victims were interviewed on socio-demographic characteristics, symptoms of anxiety (AD) and post-traumatic stress disorder (PTSD), threat experienced, and mental health support received. A 7-item Generalized Anxiety Disorder (GAD-7) and 9-item Post Traumatic Stress Disorder (PTSD) scale were used to assess the mental health status of the victims. A point was assigned to respondents who reported the symptoms of GAD, with a maximum score of 7 attained. For GAD, scores were categorized as follows: 1 - 2 as mild, 2 - 3 as minimal, 4 - 5 as moderate and 6 - 7 as severe. The PTSD symptoms were rated using a 5-point Likert scale response, and assigned the following points;4 = extremely, 3 = quite a bit, 2 = moderate, 1 = a little bit and 0 = not at all. From a maximum score of 36, participants with scores 18 and above were categorized as those with provisional PTSD. The independent samples t-test and correlational analysis were used to determine the association between PTSD score and other independent variables, with an alpha level of significance set at 0.05. Results: Generally, 38 (18.2%) of the respondents had severe AD. About half (89;42.6%) were categorized as those with provisional PTSD. The mean level of both AD (3.40 ± 2.26) and PTSD (16.51 ± 7.63) score is higher among those who were married compared to those not married (anxiety disorder;2.52 ± 2.20, P = 0.005 and PTSD;13.20 ± 8.86, P = 0.004). Respondents who have been counseled by a healthcare worker had a higher mean level (15.89 ± 7.58) of provisional PTSD compared to those not counseled by a healthcare worker (13.56 ± 9.22, P = 0.046). The level of PTSD score increased with a higher age group (r = 0.21, P = 0.003). Conclusions: The results show that the mass attack had psychological consequences among a high proportion of the victims, particularly, those married and in the older age groups. This suggests the need for continuous supportive counseling targeting these affected groups, and considering other factors moderating the effectiveness of counseling among them in future interventions. 展开更多
关键词 mass Attack mass Casualty Anxiety Disorder Posttraumatic Stress Disorder
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Application of Mass Spectrometry (MS)-coupled Techniques in Pesticide Residue Detection 被引量:1
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作者 Lei WANG Rundong Qiang +5 位作者 Aili XIANG Liang ZHANG Mingyuan YUN Huihui LIU Shuo YANG Jinlu LI 《Agricultural Biotechnology》 CAS 2023年第5期59-61,共3页
Pesticide residue detection is an important work to ensure the quality safety of agricultural products.In the process of agricultural production,in order to prevent and control agricultural diseases and pests,a certai... Pesticide residue detection is an important work to ensure the quality safety of agricultural products.In the process of agricultural production,in order to prevent and control agricultural diseases and pests,a certain amount of pesticides need to be used.However,if pesticides are used excessively,there will be certain pesticide residues in crops and related products.Therefore,it is necessary to do a good job in pesticide residue detection.The gas chromatography-mass spectrometry(GC-MS)and liquid chromatography-mass spectrometry(LC-MS)detection methods have good results and can effectively detect pesticide residues in related products.This paper reviewed and analyzed the application of GC-MS and LC-MS in pesticide residue detection,and proposed optimization measures based on practical experience,hoping to provide reference for relevant scholars. 展开更多
关键词 Gas chromatography-mass spectrometry Liquid chromatography-mass spectrometry Pesticide residues Detection analysis APPLICATION
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Intelligent geochemical interpretation of mass chromatograms:Based on convolution neural network
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作者 Kai-Ming Su Jun-Gang Lu +2 位作者 Jian Yu Zi-Xing Lu Shi-Jia Chen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期752-764,共13页
Gas chromatography-mass spectrometry(GC-MS)is an extremely important analytical technique that is widely used in organic geochemistry.It is the only approach to capture biomarker features of organic matter and provide... Gas chromatography-mass spectrometry(GC-MS)is an extremely important analytical technique that is widely used in organic geochemistry.It is the only approach to capture biomarker features of organic matter and provides the key evidence for oil-source correlation and thermal maturity determination.However,the conventional way of processing and interpreting the mass chromatogram is both timeconsuming and labor-intensive,which increases the research cost and restrains extensive applications of this method.To overcome this limitation,a correlation model is developed based on the convolution neural network(CNN)to link the mass chromatogram and biomarker features of samples from the Triassic Yanchang Formation,Ordos Basin,China.In this way,the mass chromatogram can be automatically interpreted.This research first performs dimensionality reduction for 15 biomarker parameters via the factor analysis and then quantifies the biomarker features using two indexes(i.e.MI and PMI)that represent the organic matter thermal maturity and parent material type,respectively.Subsequently,training,interpretation,and validation are performed multiple times using different CNN models to optimize the model structure and hyper-parameter setting,with the mass chromatogram used as the input and the obtained MI and PMI values for supervision(label).The optimized model presents high accuracy in automatically interpreting the mass chromatogram,with R2values typically above 0.85 and0.80 for the thermal maturity and parent material interpretation results,respectively.The significance of this research is twofold:(i)developing an efficient technique for geochemical research;(ii)more importantly,demonstrating the potential of artificial intelligence in organic geochemistry and providing vital references for future related studies. 展开更多
关键词 Organic geochemistry BIOMARKER mass chromatographic analysis Automated interpretation Convolution neural network Machine learning
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Simultaneous Determination of 14 β-Receptor Agonists Residues in Mutton by High Performance Liquid Chromatography-Tandem Mass Spectrometry (HPLC-MS/MS)
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作者 Zhe MENG Jianhua WANG +5 位作者 Bo LIU Yuhang GUO Haoshuang DONG Pingyang SHAN Dawei WANG Yajuan SONG 《Agricultural Biotechnology》 CAS 2023年第5期55-58,共4页
[Objectives]A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method was established for the determination of 14β-receptor agonist residues in mutton.[Methods]Samples were hydrolyzed byβ-g... [Objectives]A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method was established for the determination of 14β-receptor agonist residues in mutton.[Methods]Samples were hydrolyzed byβ-glucuronidase and extracted with 5%acetic acid-acetonitrile(1:99,V/V)solution.An Eclipse plus C 18 column was used for separation,and the MRM mode was used for qualitative analysis,and the external standard method was used for quantitative analysis of matrix standard solutions.[Results]Under the optimal conditions,the retention time of the 14 kinds ofβ-receptor agonists ranged from 1.0 to 9.5 min.When the mass concentration was in the range of 0.05-0.50μg/ml,the linear relationship ofβ-receptor agonists was good,with correlation coefficients(r)≥0.9992.The detection limits of the method were in the range of 0.04-0.87μg/kg,and the quantitative limits were in the range of 0.35-1.86μg/kg.The average recovery values were in the range of 82.8%-108.9%,with RSDs(n=6)in the range of 1.9%-6.7%.[Conclusions]The method is simple,sensitive,reproducible,accurate,and can be used for simultaneous determination of the 14 kinds ofβ-receptor agonist residues in mutton. 展开更多
关键词 MUTTON High performance liquid chromatography-tandem mass spectrometry β-receptor agonist RESIDUE
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Chemical profiling of bioactive compounds in the methanolic extract of wild leaf and callus of Vitex negundo using gas chromatographymass spectrometry
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作者 Gunjan Garg Alok Bharadwaj +1 位作者 Shweta Chaudhary Veena Gupta 《World Journal of Experimental Medicine》 2024年第1期78-87,共10页
BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.neg... BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.negundo),a perennial herb belonging to the Varbanaceae family,is extensively used in conventional medication.AIM To determine the existence of therapeutic components in leaf and callus extracts from wild V.negundo plants using gas chromatography-mass spectrometry(GCMS).METHODS In this study,we conducted GC-MS on wild plant leaf extracts and correlated the presence of constituents with those in callus extracts.Various growth regulators such as 6-benzylaminopurine(BAP),2,4-dichlorophenoxyacetic acid(2,4-D),α-naphthylacetic acid(NAA),and di-phenylurea(DPU)were added to plant leaves and in-vitro callus and grown on MS medium.RESULTS The results clearly indicated that the addition of BAP(2.0 mg/L),2,4-D(0.2 mg/mL),DPU(2.0 mg/L)and 2,4-D(0.2 mg/mL)in MS medium resulted in rapid callus development.The plant profile of Vitex extracts by GC-MS analysis showed that 24,10,and 14 bioactive constituents were detected in the methanolic extract of leaf,green callus and the methanolic extract of white loose callus,respectively.CONCLUSION Octadecadienoic acid,hexadecanoic acid and methyl ester were the major constituents in the leaf and callus methanolic extract.Octadecadienoic acid was the most common constituent in all samples.The maximum concentration of octadecadienoic acid in leaves,green callus and white loose callus was 21.93%,47.79%and 40.38%,respectively.These findings demonstrate that the concentration of octadecadienoic acid doubles in-vitro compared to in-vivo.In addition to octadecadienoic acid;butyric acid,benzene,1-methoxy-4-(1-propenyl),dospan,tridecanedialdehyde,methylcyclohexenylbutanol,chlorpyrifos,n-secondary terpene diester,anflunine and other important active compounds were also detected.All these components were only available in callus formed in-vitro.This study showed that the callus contained additional botanical characteristics compared with wild plants.Due to the presence of numerous bioactive compounds,the medical use of Vitex for various diseases has been accepted and the plant is considered an important source of therapeutics for research and development. 展开更多
关键词 Leaf extracts Callus extracts Methanolic extract Octadecadienoic acid Hexadecanoic acid Methyl ester Gas chromatography-mass spectrometry analysis
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基于GC-IMS和GC-MS技术结合化学计量法分析干燥方式对香椿挥发性成分的影响
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作者 张乐 魏依馨 +5 位作者 史冠莹 蒋鹏飞 赵丽丽 王继红 张少南 王赵改 《食品工业科技》 CAS 北大核心 2024年第11期222-234,共13页
为研究干燥方式对香椿挥发性风味物质的影响,利用气相色谱-离子迁移谱技术(gaschromatography-ion mobility spectrometry,GC-IMS)和气相色谱-质谱联用技术(gas chromatography-mass spectrometry,GC-MS)、相对香气活性值(relative odor... 为研究干燥方式对香椿挥发性风味物质的影响,利用气相色谱-离子迁移谱技术(gaschromatography-ion mobility spectrometry,GC-IMS)和气相色谱-质谱联用技术(gas chromatography-mass spectrometry,GC-MS)、相对香气活性值(relative odor activity value,ROAV)对真空冷冻干燥、热泵干燥、热风干燥、微波真空干燥的香椿样品进行挥发性成分分析,并进一步结合化学计量方法主成分分析(principal component analysis,PCA)和偏最小二乘判别分析(partial least squares-discriminant analysis,PLS-DA),探究样品间挥发性成分的差异性。结果表明,通过GC-IMS检测到78个峰,鉴定出59种化合物。通过GC-MS鉴定出94种挥发性化合物,主要挥发性成分是硫化物、烯烃类和醛类。经过干燥后总挥发性化合物的含量显著降低。通过ROAV法确定了(E,Z)-二-1-丙烯基二硫化物、2-巯基-3,4-二甲基-2,3-二氢噻吩、正己醛、2-己烯醛、丁香酚等为香椿样品中关键香气化合物。PCA和PLS-DA结果表明,不同干燥方式的样品与新鲜样品有明显的分离,彼此之间也有明显的区别。鲜样和真空冷冻干燥样品为一组,其他3个干燥香椿样品为一组。根据变量投影重要性(variable importance in projection,VIP)得分共筛选出10种(VIP>1)标志挥发性化合物。干燥方式对香椿风味特性影响显著,真空冷冻干燥组与鲜样最为接近,考虑实际应用热泵干燥为香椿最适宜的脱水方式。本研究为热加工过程中风味品质控制提供一定的理论参考。 展开更多
关键词 香椿 干燥方式 气相色谱-离子迁移谱(GC-Ims) 气相色谱-质谱联用技术(GC-ms) 挥发性化合物
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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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基于HS-SPME-GC-MS的不同成熟度‘青皮’无花果挥发性成分分析
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作者 刘雪梅 闫新焕 +4 位作者 谭梦男 谷思梦 杜文瑜 许敏 宋烨 《中国果菜》 2024年第4期14-19,共6页
为探讨不同成熟度威海‘青皮’无花果挥发性成分差异,本研究采用固相微萃取(SPME)和气相色谱-质谱联用技术(GC-MS)对鲜食无花果挥发性成分进行分析,并采用内标法对风味物质进行定量分析。结果显示,在威海‘青皮’无花果中共检测出73种... 为探讨不同成熟度威海‘青皮’无花果挥发性成分差异,本研究采用固相微萃取(SPME)和气相色谱-质谱联用技术(GC-MS)对鲜食无花果挥发性成分进行分析,并采用内标法对风味物质进行定量分析。结果显示,在威海‘青皮’无花果中共检测出73种挥发性成分,主要为酯类、醛类、醇类、烯类、烷烃类等,其中六成熟无花果检出33种、八成熟检出29种、十成熟检出36种。不同成熟度无花果的挥发性组分、特征风味物质种类和含量差异明显。 展开更多
关键词 无花果 挥发性成分 气相色谱-质谱联用技术 固相微萃取
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GC-MS结合电子鼻技术对不同茶区茉莉花茶香气的差异比较
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作者 李璐 尹礼国 +4 位作者 陆安霞 王秋卫 陈丽 赵先明 黄彤 《现代食品科技》 CAS 北大核心 2024年第2期302-311,共10页
为探究不同产区茉莉花茶香气差异,采用气相色谱-质谱(GasChromatography-Mass Spectrometry,GC-MS)结合电子鼻(Electronic Nose,E-nose)技术对西南、华南、江南三大茶区的8种茉莉花茶进行香气研究。结果表明,8个样品共鉴定出香气成分58... 为探究不同产区茉莉花茶香气差异,采用气相色谱-质谱(GasChromatography-Mass Spectrometry,GC-MS)结合电子鼻(Electronic Nose,E-nose)技术对西南、华南、江南三大茶区的8种茉莉花茶进行香气研究。结果表明,8个样品共鉴定出香气成分58种,其中西南、江南、华南茶区分别为45种、51种、47种。江南茶区香气化合物总量最高。共有香气成分主要包括邻氨基苯甲酸甲酯、顺式-3-己烯醇苯甲酸酯、乙酸苄酯、水杨酸甲酯、芳樟醇、吲哚等。其中水杨酸甲酯在江南茶区含量最高(22.32μg/g),分别较华南、西南茶区高33.96%、68.01%;邻氨基苯甲酸甲酯(67.39μg/g)和吲哚(43.84μg/g)含量在华南茶区最高。茉莉花茶香气评价指数(JasmineTea Flavor Index,JTF index)分析表明西南茶区样品等级最高。香气聚类分析将共有香气成分分为3类,分别呈花香、茉莉花香和草木香。通过电子鼻技术可知样品香气物质变化与硫化物、碳氢化合物、芳香化合物有关,并能有效区别样品香气。综上,三大茶区样品香气种类差异不明显,但各香气成分含量差异显著(P<0.05),江南和华南茶区的样品特征性香气成分含量较高,西南茶区样品综合指数高。 展开更多
关键词 香气 茉莉花茶 气相色谱-质谱法(GC-ms) 电子鼻 茉莉花茶香气评价指数(JTF index)
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基于不确定度评估研究ID-LC-MS/MS法检测鸡蛋中氟虫腈砜残留量的关键控制点
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作者 张巧艳 方维焕 +3 位作者 郑蔚然 王夏君 刘超纲 王强 《浙江农业学报》 CSCD 北大核心 2024年第3期643-650,共8页
为了控制检测结果准确性,以鸡蛋粉中氟虫腈砜残留分析标准物质[GBW(E)100779]为测试样,采用“自下而上”法对基于多功能净化柱(PAC柱)净化的同位素稀释液相色谱串联质谱(ID-LC-MS/MS)法进行测量不确定度评估。“鱼骨图”分析表明,不确... 为了控制检测结果准确性,以鸡蛋粉中氟虫腈砜残留分析标准物质[GBW(E)100779]为测试样,采用“自下而上”法对基于多功能净化柱(PAC柱)净化的同位素稀释液相色谱串联质谱(ID-LC-MS/MS)法进行测量不确定度评估。“鱼骨图”分析表明,不确定度分量主要来源有样品称样量、内标溶液添加体积、标准工作溶液浓度及其移取体积。内标溶液添加体积引入的不确定度最大,对检测结果不确定度的贡献率为68.59%;万分之一天平称量引入的不确定度可忽略不计。同位素内标的添加过程是ID-LC-MS/MS法检测的关键控制点,参考基准的合理选择和目标物的完全提取是准确测量的前提。进一步用LC-MS/MS法对参考物质、稀释剂和内标溶液的适用性进行了评估,并基于国家有证标准物质[GBW(E)100779]对提取方法进行了优化。研究结果有利于提升鸡蛋食品安全的检测质量和质控水平,为精准检测质控方案的设计提供新思路。 展开更多
关键词 测量不确定度 鸡蛋 氟虫腈砜 同位素稀释液相色谱串联质谱法(ID-LC-ms/ms) 质量控制 标准物质
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ICP-MS/MS测定轻质油中痕量氯含量
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作者 李爱阳 陈宇 +1 位作者 殷子懿 陈林 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第3期813-819,共7页
基于H_(2)反应模式下的质量转移反应消除干扰,建立电感耦合等离子体串联质谱(ICP-MS/MS)测定轻质油中痕量Cl的分析方法。轻质油经简单稀释后直接采用ICP-MS/MS进行测定,在MS/MS模式下使用H_(2)作为反应气,利用在碰撞/反应池(CRC)中Cl^(+... 基于H_(2)反应模式下的质量转移反应消除干扰,建立电感耦合等离子体串联质谱(ICP-MS/MS)测定轻质油中痕量Cl的分析方法。轻质油经简单稀释后直接采用ICP-MS/MS进行测定,在MS/MS模式下使用H_(2)作为反应气,利用在碰撞/反应池(CRC)中Cl^(+)与H_(2)发生二次H原子转移反应形成的子离子(H_(2)Cl^(+))进行测定,消除所有质谱干扰,获得Cl的灵敏度和检出限(LOD)明显优于O_(2)反应模式,LOD低至7.56μg/kg。通过与扇型磁场ICP-MS(SF-ICP-MS)对比分析标准参考物质NIST SRM 1634c,评价方法的准确可靠性。结果表明,标准参考物质的分析结果与认证值基本一致,相对标准偏差(RSD)为3.1%~4.7%,2种方法的对比分析结果在95%的置信度水平无显著性差异。所建立分析方法的灵敏度、准确度和和精密度高,MS/MS模式和H_(2)质量转移法的结合可无干扰测定轻质油中的Cl,适用于轻质油中痕量Cl的质量控制与评估。 展开更多
关键词 轻质油 电感耦合等离子体串联质谱 Cl 碰撞/反应池 H原子转移
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Spatiotemporal pharmacometabolomics based on ambient mass spectrometry imaging to evaluate the metabolism and hepatotoxicity of amiodarone in HepG2 spheroids 被引量:3
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作者 Limei Li Qingce Zang +5 位作者 Xinzhu Li Ying Zhu Shanjing Wen Jiuming He Ruiping Zhang Zeper Abliz 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第5期483-493,共11页
Three-dimensional(3D)cell spheroid models combined with mass spectrometry imaging(MSI)enables innovative investigation of in vivo-like biological processes under different physiological and pathological conditions.Her... Three-dimensional(3D)cell spheroid models combined with mass spectrometry imaging(MSI)enables innovative investigation of in vivo-like biological processes under different physiological and pathological conditions.Herein,airflow-assisted desorption electrospray ionization-MSI(AFADESI-MSI)was coupled with 3D HepG2 spheroids to assess the metabolism and hepatotoxicity of amiodarone(AMI).High-coverage imaging of>1100 endogenous metabolites in hepatocyte spheroids was achieved using AFADESI-MSI.Following AMI treatment at different times,15 metabolites of AMI involved in Ndesethylation,hydroxylation,deiodination,and desaturation metabolic reactions were identified,and according to their spatiotemporal dynamics features,the metabolic pathways of AMI were proposed.Subsequently,the temporal and spatial changes in metabolic disturbance within spheroids caused by drug exposure were obtained via metabolomic analysis.The main dysregulated metabolic pathways included arachidonic acid and glycerophospholipid metabolism,providing considerable evidence for the mechanism of AMI hepatotoxicity.In addition,a biomarker group of eight fatty acids was selected that provided improved indication of cell viability and could characterize the hepatotoxicity of AMI.The combination of AFADESI-MSI and HepG2 spheroids can simultaneously obtain spatiotemporal information for drugs,drug metabolites,and endogenous metabolites after AMI treatment,providing an effective tool for in vitro drug hepatotoxicity evaluation. 展开更多
关键词 mass spectrometry imaging HepG2 spheroids HEPATOTOXICITY Drug metabolism AMIODARONE
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基于破乳诱导萃取和ICP-MS/MS分析渣油中的微量金属元素
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作者 朱乾华 刘宏伟 聂西度 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第1期229-238,共10页
基于破乳诱导萃取提出利用电感耦合等离子体串联质谱(ICP-MS/MS)测定渣油中多种金属元素的新策略。渣油样品经二甲苯稀释降低黏度后采用质量分数6%的Triton X-114乳化,超声水浴破乳25 min,利用体积分数40%的盐酸萃取渣油中金属元素至水... 基于破乳诱导萃取提出利用电感耦合等离子体串联质谱(ICP-MS/MS)测定渣油中多种金属元素的新策略。渣油样品经二甲苯稀释降低黏度后采用质量分数6%的Triton X-114乳化,超声水浴破乳25 min,利用体积分数40%的盐酸萃取渣油中金属元素至水相,采用ICP-MS/MS测定其中10种金属元素Na、Mg、Al、Ca、V、Cr、Fe、Ni、Cu、Zn的含量。详细评估了破乳诱导萃取条件对渣油中金属元素萃取效率的影响,在串联质谱(MS/MS)模式下,利用氦碰撞气或不同反应气消除了金属元素的质谱干扰,采用标准参考物质NIST SRM 1634c(燃油中的微量元素)验证了方法的准确性,以微波消解技术处理渣油样品并采用扇形磁场电感耦合等离子体质谱(SF-ICP-MS)进行对比分析验证了方法的可靠性。结果显示,金属元素在各自的含量范围内呈现良好的线性关系(线性相关系数≥0.9997),检出限(LOD)为2.05~31.4 ng/L,NIST SRM 1634c的测定结果与标准参考物质提供的认证值及文献报道的参考值基本一致,置信度水平达到95%,ICP-MS/MS方法与SF-ICP-MS的对比分析结果无显著性差异。所建立的ICP-MS/MS方法操作简单,分析速率快,准确可靠性好,已用于渣油中多种金属元素的质量评价。 展开更多
关键词 渣油 电感耦合等离子体串联质谱(ICP-ms/ms) 金属元素 破乳诱导萃取 质谱干扰
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自动QuEChERS结合UPLC-MS/MS测定莲雾中苯并咪唑类农药残留
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作者 齐宁利 刘元婧 +3 位作者 陈吴海 莫华升 林梅清 龚霄 《保鲜与加工》 CAS 北大核心 2024年第5期98-103,共6页
为了建立自动QuEChERS结合高效液相色谱-串联质谱法测定莲雾中多菌灵、噻菌灵、苯菌灵及甲基硫菌灵4种苯并咪唑类农药残留量的检测方法。将莲雾样品采用混合试剂(5.5 g硫酸镁+1.5 g氯化钠+1.0 g柠檬酸钠+0.5 g柠檬酸二钠)进行净化,经QuE... 为了建立自动QuEChERS结合高效液相色谱-串联质谱法测定莲雾中多菌灵、噻菌灵、苯菌灵及甲基硫菌灵4种苯并咪唑类农药残留量的检测方法。将莲雾样品采用混合试剂(5.5 g硫酸镁+1.5 g氯化钠+1.0 g柠檬酸钠+0.5 g柠檬酸二钠)进行净化,经QuEChERS自动样品制备系统进行制备后,应用超高效液相色谱-三重四级杆串联质谱法进行分析。结果表明,4种农药在1.00~10.00 ng/mL质量浓度范围内线性关系良好,决定系数(R2)均大于0.99;0.1、1.0、5.0 mg/kg 3个添加水平下,在莲雾基质中添加回收率为84%~105%,相对标准偏差为0.8%~9.5%(n=3),方法检出限和定量限分别为0.1~0.5μg/kg和0.5~10.0μg/kg。综上,该方法简便省时,净化效果好,灵敏度及准确度高,可用于同时测定莲雾中多菌灵、噻菌灵、苯菌灵及甲基硫菌灵4种苯并咪唑类农药的残留量。 展开更多
关键词 自动QuEChERS 莲雾 苯并咪唑 农药残留 超高效液相色谱-三重四级杆串联质谱法
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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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基于UHPLC-Q-Exactive Orbitrap HRMS技术结合化学计量学方法的不同干燥处理杜仲叶成分分析
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作者 李淑芳 王会锋 +6 位作者 郝学飞 胡永建 李圆圆 马风莲 冯书惠 杨亚琴 于永杰 《分析测试学报》 CAS CSCD 北大核心 2024年第2期213-225,共13页
采用基于液质联用的非靶向代谢组学技术结合化学计量学数据自动解析软件AntDAS-LCHRMS分析了4种不同干燥处理(冻干、热泵烘干、电热烘干、晒干)杜仲叶样本中的化合物。杜仲叶样本数据由超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UH... 采用基于液质联用的非靶向代谢组学技术结合化学计量学数据自动解析软件AntDAS-LCHRMS分析了4种不同干燥处理(冻干、热泵烘干、电热烘干、晒干)杜仲叶样本中的化合物。杜仲叶样本数据由超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UHPLC-Q-Exactive Orbitrap HRMS)分别在正、负离子模式下进行采集,经AntDAS-LCHRMS软件解析,共鉴定出71种差异性化合物,经标准品验证确定40种化合物,包括环烯醚萜类、有机酸类、黄酮类、氨基酸类、核苷类、维生素类等9类物质。其中,正、负离子模式下均可识别并验证的化合物有车叶草苷、绿原酸、芦丁、异槲皮苷、车叶草苷酸、京尼平苷等25种化合物。层次聚类分析(HCA)及主成分分析(PCA)结果均显示,相同处理的杜仲叶样本各自聚成一类,不同处理的杜仲叶样本可明显区分。热图分析进一步揭示了不同干燥处理杜仲叶样本中差异性化合物的含量变化。晒干处理样本中苯丙氨酸及色氨酸等氨基酸类物质的水平较高;冻干及热泵烘干处理样本中有机酸类、环烯醚萜类、糖类等含量较高;电热烘干样本中核苷类、黄酮类物质的含量较高;黄酮类物质在冻干、热泵烘干及晒干样本中差异较小。研究结果为不同干燥处理杜仲叶的成分分析、品质评价及其开发应用提供了科学依据,也可为其他复杂药用植物体系的化学成分分析提供参考。 展开更多
关键词 杜仲叶 代谢组学 化学计量学 AntDAS-LCHRms软件 超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UHPLC-Q-Exactive Orbitrap HRms) 干燥处理
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UPLC-MS/MS法检测3种食品中松仁过敏原
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作者 宁亚维 周泓鑫 +4 位作者 杨正 马俊美 刘茁 张岩 李强 《食品科学》 EI CAS CSCD 北大核心 2024年第1期247-253,共7页
基于食品基质中松仁过敏原Pin k 2建立了一种超高效液相色谱-串联质谱法。将松仁经过研磨、脱脂、浸提、酶解后经Easy-nLC 1000-QExactive高分辨质谱仪进行分离分析,结合Uniprot蛋白数据库以及ProteinPilotTM软件对质谱图进行数据处理,... 基于食品基质中松仁过敏原Pin k 2建立了一种超高效液相色谱-串联质谱法。将松仁经过研磨、脱脂、浸提、酶解后经Easy-nLC 1000-QExactive高分辨质谱仪进行分离分析,结合Uniprot蛋白数据库以及ProteinPilotTM软件对质谱图进行数据处理,经BLAST验证特异性,最终筛选3条松仁特异性肽段。方法学验证结果表明,方法在0.001~50mg/mL范围内线性关系良好,定量限为1mg/kg;在饼干、巧克力和饮料3种空白基质中的平均回收率为88.50%~107.57%,相对标准偏差不高于6.08%,基质效应为89.77%~96.13%。该方法具有灵敏度高、特异性好的优势,可应用于饼干、巧克力、饮料等食品样品中松仁过敏原的检测,为我国食品标签真实性检验及食品中隐性过敏原的检测提供技术支持。 展开更多
关键词 松仁 过敏原 超高效液相色谱-串联质谱法 检测
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