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The Essential Oil of Ocimum americanum from Senegal and Gambia as a Source of Methyleugenol for the Control of Bactrocera dorsalis, Fruit Fly

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Journal of Agricultural Chemistry and Environment 2024年第1期13卷 133-141页

作者： Yoro Tine Antonio Alain Coffi Sinzogan Ousmane Ndiaye Cebastiana Sambou Alioune Diallo Ismaila Mbenga Kemo Badji El Hadji Omar Dieng Assa Balayara Jeanne Diatta Cheikhouna Gaye Julien Paolini Jean Costa Alassane Wele Saliou Ngom Laboratoire de Chimie Organique et Thérapeutique Faculté de Médecine Pharmacie et Odontologie Université Cheikh Anta Diop Dakar Sénégal Faculte des Sciences Agronomiques Universite d’Abomey Calavi Cotonou Benin Ecole Nationale Supérieure d’Agriculture (ENSA) Université Iba Der Thiam de Thiès Thiès Sénégal Direction de la Protection des Végétaux Rufisque Sénégal Laboratoire de Chimie des Produits Naturels Université de Corse Corte France National Agricultural Research Institute (NARI) Sere Kunda Gambia Institut Sénégalais de Recherches Agricoles (ISRA) Dakar Sénégal

The fruit fly, Bactrocera dorsalis (Diptera: Tephritidae) is one of the most important pests in all mango-producing areas, particularly in West Africa. In Senegal, O. americanum leaves have been used for several years to control this fly. However, to our knowledge, no chemical studies have been carried out. Thus, the aim of this study is to determine the chemical composition of the essential oil of O. americanum leaves collected in Senegal and Gambia. The essential oil obtained by hydrodistillation of these leaves is analyzed by gc/FID and gc/ms. Yields of essential oils from O. americanum leaves are 3.84% and 2.13%, respectively. Analysis of these essential oils by gc/FID and gc/ms allowed the identification of 23 compounds representing almost 100% of the total compositions. These essential oils are mainly dominated by methyleugenol (72.0% and 75.8%, respectively). Other components in significant percent are trans-β-caryophyllene (13.9% and 13.0%, respectively), germacrene D (4.1% and 3.7%, respectively), β-elemene (3.3% and 0.9%, respectively). Due to the high methyleugenol content, this study explains the attractive potential of O. americanum towards B. dorsalis. In perspective, we plan to evaluate the attractive effect of the essential oil and leaf powder of O. americanum against B. dorsalis, a real pest of mango orchards in Senegal.

关键词： Ocimum americanum Essential Oils Methyleugenol Bactrocera dorsalis gc/ms

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基于P&T-gc/ms指纹图谱技术的烟用香精质量控制评价方法

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轻工学报 2024年第3期39卷 54-61页

作者：吕祥敏陈云璨唐杰许嘉东蒋昊程传玲张改红朱玲重庆中烟工业有限责任公司技术中心重庆400060 郑州轻工业大学烟草科学与工程学院河南郑州450001

利用P&T-gc/ms指纹图谱技术,结合夹角余弦相似度、峰匹配及多元T^(2)控制图,对烟用香精的质量稳定性进行综合评价,结果表明:P&T最优的前处理条件为吹扫时间14 min,吹扫温度40℃,解析温度200℃,在该条件下测得烟用香精中各挥发性成分特... 详细信息

利用P&T-gc/ms指纹图谱技术,结合夹角余弦相似度、峰匹配及多元T^(2)控制图,对烟用香精的质量稳定性进行综合评价,结果表明:P&T最优的前处理条件为吹扫时间14 min,吹扫温度40℃,解析温度200℃,在该条件下测得烟用香精中各挥发性成分特征色谱峰的RSD为1.36%~6.98%,说明该方法精密度良好;指纹图谱结合夹角余弦相似度、峰匹配分析及多元T^(2)控制图,可快速识别组分发生变化的烟用香精样品,及时发现样品的错混、质量浓度改变等问题,有效监控烟用香精的质量稳定性,并有助于进一步分析化学组分发生变化的根本原因。

关键词：烟用香精吹扫捕集 gc/ms 夹角余弦相似度峰匹配多元T^(2)控制图

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塑胶中邻苯二甲酸二(2-乙基己基)酯萃取剂及萃取时间的研究

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日用电器 2024年第1期 122-125页

作者：富裕王雄辉杨浩艺嘉兴威凯检测技术有限公司嘉兴314050

本文通过研究甲苯、正己烷萃取在不同浓度的DEHP提取效率、回收率,针对塑胶制品确定了相对有效的萃取溶剂,同时通过改变超声温度挑选出最有效的超声温度,并用实际样品进行了相关实验验证。结果表明:甲苯萃取剂萃取效率更高(92.4%),超声... 详细信息

本文通过研究甲苯、正己烷萃取在不同浓度的DEHP提取效率、回收率,针对塑胶制品确定了相对有效的萃取溶剂,同时通过改变超声温度挑选出最有效的超声温度,并用实际样品进行了相关实验验证。结果表明:甲苯萃取剂萃取效率更高(92.4%),超声萃取温度与30℃时效率最高,标液线性良好(R^(2)=0.999 8),回收率在(92.3~95.2)%。

关键词：邻苯二甲酸二(2-乙基己基)酯超声萃取提取温度 gc/ms

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Experimental and Theoretical Studies of C_(3)F_(7)CN/CO_(2) Mixture Decomposition Under Overheating Fault

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CSEE Journal of Power and Energy Systems 2022年第3期8卷 941-951页

作者： Mingyue Zhao Dong Han Weikang Zhao Zhenrui Zhou Guoqiang Zhang Institute of Electrical Engineering Chinese Academy of Sciencesand University of Chinese Academy of SciencesBeijing 100190China

Heptafluoroisobutyrontrile(C_(3)F_(7)CN)performs well in dielectric properties and environmental protection,which has the potential to replace SF6 gas.The decomposition characteristics of C_(3)F_(7)CN mixture under fault conditions directly affect the possibility of its replacement for SF6 gas.However,the number of studies on the decomposition characteristics of C_(3)F_(7)CN mixture under overheating fault is less.In this paper,the decomposition characteristics of C_(3)F_(7)CN/CO_(2) mixture under an overheating fault are studied by gas chromatography-mass spectrometry(gc/ms)and quantum chemical calculations.Byproducts CO,C_(3)F_(6) and HF are detected at 200℃.At 550℃,the C_(3)F_(7)CN molecule begins to decompose and produces CHF_(3),C_(2)F_(4),CF_(3)CN and CNCN.Moreover,the results of gc/ms show that the insulation medium C_(3)F_(7)CN contains an impurity,which is C3HF7(HFC-227ea).Combined with the results of gc/ms and quantum chemistry calculations,it can be concluded that the decomposition by-product C_(3)F_(6) at 200℃ mainly comes from the decomposition of C_(3)HF_(7).C_(3)HF_(7) reduces the decomposition temperature of the C_(3)F_(7)CN/CO_(2) mixture.Therefore,it is very important to improve the purity of the insulation medium C_(3)F_(7)CN.

关键词： C3F7CN decomposition mechanism environmentally-friendly gas-insulating medium gc/ms quantum chemical

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Simultaneous determination of brominated phenols in soils

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Journal of Environmental Sciences 2013年第11期25卷 2306-2312页

作者： Wei Han Sen Wang Honglin Huang Lei Luo Shuzhen Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Brominated phenols （BPs）, a widely used group of emerging flame retardants, are important environmental contaminants and exhibit endocrine disrupting potential. Method for simultaneous determination of tetrabromobisphenol A （TBBPA）, tribromophenol （TBP）, dibromophenols （DBPs） and monobromophenols （MBPs） in soils using gas chromatography-mass spectrometry analysis （gc/ms） was successfully developed. Cleanup methods for soil extracts including several solid-phase extraction cartridges and different elution solvents were compared and optimized. Florisil cartridge with dichloromethane as the elution reagent was selected for sample cleanup owing to its high and reproducible recoveries of the target analytes in soils. Derivatization conditions were tested and the optimal conditions were obtained with 20 μL silylation reagent at room temperature. The chromatographic separation was optimized with different columns and DB-XLB column was selected for its excellent separation of the analytes. The limits of detection for the target compounds were from 0.04 to 0.19 ng/g. Mean recoveries of the compounds from spiked soils exceeded 84% with a good reproducibility, excepting that the recovery of 2-bromophenol was relatively poor （lower than 55%） due to its instability. The developed method was applied to the determination of the BPs in the soils collected from e-waste sites. The contents of BPs in the soils were at ng/g levels with TBBPA and TBP the most frequently detected. To our knowledge, this is the first report for the simultaneous determination of TBBPA, TBP, DBPs and MBPs in soils.

关键词： brominated phenols analysis soil derivatization gc/ms

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Electrochemical treatment of olive mill wastewater:Treatment extent and effluent phenolic compounds monitoring using some uncommon analytical tools

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Journal of Environmental Sciences 2013年第1期25卷 220-230页

作者： Chokri Belaid Moncef Khadraoui Salma mseddi Monem Kallel Boubaker Elleuch Jean Franois Fauvarque Laboratory of Water Energy and Environment Sfax UniversityENIS BP "1173" 3038 Sfax Tunisia Laboratory of Industrial Electrochemistry CNAM 2 Rue Conté 75003 Paris France

Problems related with industrials effluents can be divided in two parts：（1） their toxicity associated to their chemical content which should be removed before discharging the wastewater into the receptor media; （2） and the second part is linked to the difficulties of pollution characterisation and monitoring caused by the complexity of these matrixes. This investigation deals with these two aspects, an electrochemical treatment method of an olive mill wastewater （OMW） under platinized expanded titanium electrodes using a modified Gl＂ignard reactor for toxicity removal as well as the exploration of the use of some specific analytical tools to monitor effluent phenolic compounds elimination. The results showed that electrochemical oxidation is able to remove/mitigate the OMW pollution. Indeed, 87% of OMW color was removed and all aromatic compounds were disappeared from the solution by anodic oxidation. Moreover, 55% of the chemical oxygen demand （COD） and the total organic carbon （TOC） were reduced. On the other hand, UV- Visible spectrophotometry, Gaz chromatography/mass spectrometry, cyclic voltammetry and 13C Nuclear Magnetic Resonance （NMR） showed that the used treatment seems efficaciously to eliminate phenolic compounds from OMW. It was concluded that electrochemical oxidation in a modified Grignard reactor is a promising process for the destruction of all phenolic compounds present in OMW. Among the monitoring analytical tools applied, cyclic voltammetry and 13C NMR are among the techniques that are introduced for the first time to control the advancement of the OMW treatment and gave a close insight on polyphenols disappearance.

关键词： olive mill wastewater electro-oxidation polyphenols cyclic voltammetry gc/ms 13C NMR

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Primary and secondary organic aerosol in an urban/industrial site: Sources, health implications and the role of plastic enriched waste burning

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Journal of Environmental Sciences 2021年第1期33卷 222-238页

作者： Panagiotis Georgios Kanellopoulos Eleni Verouti Eirini Chrysochou Konstantinos Koukoulakis Evangelos Bakeas National and Kapodistrian University of Athens Laboratory of Analytical ChemistryDepartment of ChemistryZografouGR-15784Greece

PM_(1)0 samples were collected from an urban/industrial site nearby Athens,where uncontrolled burning activities occur.PAHs,monocarboxylic,dicarboxylic,hydroxycarboxylic and aromatic acids,tracers from BVOC oxidation,biomass burning tracers and bisphenol A were determined.PAH,monocarboxylic acids,biomass burning tracers and bisphenol A were increased during autumn/winter,while BSOA tracers,dicarboxylic-and hydroxycarboxylic acids during summer.Regarding aromatic acids,different sources and formation mechanisms were indicated as benzoic,phthalic and trimellitic acids were peaked during summer whereas p-toluic,isophthalic and terephthalic were more abundant during autumn/winter.The Benzo[a]pyrene-equivalent carcinogenic power,carcinogenic and mutagenic activities were calculated showing significant(p<0.05)increases during the colder months.Palmitic,succinic and malic acids were the most abundant monocarboxylic,dicarboxylic and hydrocarboxylic acids during the entire sampling period.Isoprene oxidation was the most significant contributor to BSOA as the isoprene-SOA compounds were two times more abundant than the pinene-SOA(13.4±12.3 and 6.1±2.9 ng/m^3,respectively).Ozone has significant impact on the formation of many studied compounds showing significant correlations with:isoprene-SOA(r=0.77),hydrocarboxylic acids(r=0.69),pinene-SOA(r=0.63),dicarboxylic acids(r=0.58),and the sum of phthalic,benzoic and trimellitic acids(r=0.44).PCA demonstrated five factors that could explain sources including plastic enriched waste burning(30.8%),oxidation of unsaturated fatty acids(23.0%),vehicle missions and cooking(9.2%),biomass burning(7.7%)and oxidation of VOCs(5.8%).The results highlight the significant contribution of plastic waste uncontrolled burning to the overall air quality degradation.

关键词： Primary organic aerosol(POA) Secondary organic aerosol(SOA) Plastic waste burning emissions gc/ms Source apportionment PCA

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Characterization of fine organic particulate matter from Chinese cooking

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Journal of Environmental Sciences 2004年第4期16卷 570-575页

作者： HELing-yan HUMin WANGLi HUANGXiao-feng ZHANGYuan-hang StateKeyJointLaboratoryofEnvironmentalSimulationandPollutionControl DepartmentofEnvironmentalSciencesCollegeofEnvironmentalSciencesPekingUniversityBeijing100871China BeijingMunicipalInstituteofLaborProtection Beijing100054China

PM 2.5 samples were collected by a three-stage cascade impactor at two kinds of Chinese restaurants to characterize fine organic particulate matter from Chinese cooking sources. Major individual organic compounds have been quantified by gc/ms, including series of alkanes, n-alkanoic acids, n-alkanals, alkan-2-ones and PAHs. Alkanes and ketones make up a significant fraction of particle-phase organic compounds, ranging from C 11 to C 26, and C 9 to C 19, respectively. In addition, other organic compound classes have been identified, such as alkanols, esters, furans, lactones, amides, and nitriles. The mass concentrations of fine particles, alkanes, n-alkanoic acids and PAHs in air emitted from the Uigur style cooking are hundreds times higher than ambient PM 2.5in Beijing.

关键词： Chinese cooking source fine organic particles gc/ms

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Determination of methyl tert-butyl ether(MTBE) in Chinese fuels by gas chromatography/mass spectrometry and gas chromatography/flame ionization detector

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Journal of Environmental Sciences 2004年第4期16卷 553-555页

作者： LIUJie-min CHENGWei WENMei-juan JIANGGui-bin esearchCenterforEco-EnvironmentalSciences ChineseAcademyofSciencesBeijing100085China DepartmentofChemistry BeijingUniversityofScienceandTechnologyBeijing100083China

A method was developed to determine the concentration of methyl tert-butyl ether(MTBE) in gasoline, diesel and heating oil by gas chromatography(gc) with mass spectrometry(gc-ms) or flame ionization detection(FID). The diluted gasoline was directly injected into the gc, and the complete separation of MTBE from co-eluting hydrocarbons was not required. gc/ms or gc/FID method can be used to analyze MTBE in different concentration range and have good consistency.

关键词： methyl tert-butyl ether(MTBE) gc/ms gc/FID

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New advances in coal structure model

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International Journal of Mining Science and Technology 2018年第4期28卷 541-559页

作者： Qin Zhihong School of Chemical Engineering China University of Mining & Technology

Although human beings have come to understand and utilize coal for a very long history, no theoretical breakthrough in the study of coal structure has been made, which still needs continuous efforts of coal chemical workers. Based on the viewpoint of ‘vague/clear', the species classification and accurate analysis on coal were conducted by using the natural clustering all-component separation method. A more systematic and detailed coal embedded structure model theory which is suitable for coal of all ranks was developed from the previous one and a more complete theoretical system about the component and structure of coal was constructed. The whole establishment process of the theory was summarized and some of the main support data and analysis test results, including TEM, AFM, FTIR, gc/ms, MALDI/TOF/ms, DART/msD, fractal analysis and so on were provided. The coal embedded structure theory fully considers both the identity and the particularity of all-rank coal, reflects the coal component and structure in the full range of coal rank, solves the systematic cognitive problem of coal component and structure on macro and micro level, and provides a valuable and meaningful theoretical approach for the coal processing and conversion technology.

关键词：用煤组织模型煤结构 gc/ms MALDI 分离方法精确分析模型理论

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