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GC-MS结合微量QuEChERS法快速测定土壤中16种多环芳烃 被引量:16
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作者 谭华东 张汇杰 武春媛 《中国测试》 CAS 北大核心 2020年第1期64-70,共7页
为实现土壤样品中典型持久性污染物的快速、灵敏及批量测定,通过基于改进微量-QuEChERS(μ-QuEChERS)技术结合超声辅助方法,且与气相色谱质谱联用(GC-MS)分析,建立土壤中16种多环芳烃(PAHs)快速测定方法。少量土壤(1.0 g)样品经过2.0 m... 为实现土壤样品中典型持久性污染物的快速、灵敏及批量测定,通过基于改进微量-QuEChERS(μ-QuEChERS)技术结合超声辅助方法,且与气相色谱质谱联用(GC-MS)分析,建立土壤中16种多环芳烃(PAHs)快速测定方法。少量土壤(1.0 g)样品经过2.0 mL乙腈与二氯甲烷(V/V=1∶2)辅助15.0 min超声提取后,利用N-丙基乙二胺(PSA)和C18混合分散剂快速涡旋净化,离心、转换溶剂后进行GC-MS外标法测定。结果表明,在2~800μg/L浓度范围内,16种PAHs呈现良好的线性关系,相关系数均在0.9920以上,检测限(LOD,S/N=3)低于0.50μg/kg。在8.0,20.0,100.0μg/kg加标浓度下,16种PAHs的加标回收率在70.3%~109.1%(n=3)。该方法快速、简单、准确,需样量少、环境污染小,可为土壤中PAHs的快速筛查提供批量检测方法。 展开更多
关键词 QUECHERS 气相色谱质谱 土壤 多环芳烃
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Cohesion Analysis inThe Water Babies --Based on Systemic-Functional Grammar
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作者 张汇杰 《海外英语》 2018年第23期234-235,共2页
Under the guidance of Systemic-Functional Grammar(SFG),cohesion is applied to analyze the selected context.Cohesion plays a great role in organizing a whole context and it can be further divided into grammatical cohes... Under the guidance of Systemic-Functional Grammar(SFG),cohesion is applied to analyze the selected context.Cohesion plays a great role in organizing a whole context and it can be further divided into grammatical cohesion and lexical cohesion.Main ideas of cohesion are illustrated and made it for application,which employs British children's literature-The Water Babies as the object.The research method adopted here is mainly quantitative.Through analyzing selected sections,it is obvious that cohesion helps readers understand the contexts better.Besides,the use of cohesion makes the context more precise and compact.For context,the role of cohesion is irreplaceable. 展开更多
关键词 Systemic-Functional GRAMMAR (SFG) COHESION The WATER Babies context
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Cubism in William Carlos Williams' Works--Taking Lines and The Disputants as Examples
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作者 张汇杰 《海外英语》 2018年第23期206-207,共2页
William Carlos Williams(1883-1963),who was born in New jersey,is viewed as the greatest poet of the 20thcentury.Williams spent his whole life implementing the local color of American and the colloquial expressions of ... William Carlos Williams(1883-1963),who was born in New jersey,is viewed as the greatest poet of the 20thcentury.Williams spent his whole life implementing the local color of American and the colloquial expressions of poetry.Here,it mainly explores Cubism in Williams'works and takes two poems as examples,which are Lines and The Disputants.With the help of cubist ideas,readers could easily understand Williams'words and structures.Besides,through analyzing Williams'poems,it is obvious that it is even hard for readers to observe the boundaries of poetry and paintings.Thereupon,Cubism helps readers to decode Williams'poetry. 展开更多
关键词 WILLIAM Carlos WILLIAMS CUBISM LINES The Disputants
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