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1.
建立了一种非平衡固相微萃取与气相色谱-质谱联用快速监测水中氯化苄的新方法,整个分析过程只需15min。85μm的聚丙烯酸酯涂层(PA)对水中的氯化苄有较好的萃取效果。方法的线性范围为1-50μg/L,检出限为0.91μg/L,相对标准偏差为9.86%,用于河水中氯化苄的测定,结果满意。  相似文献   

2.
固相微萃取气相色谱法(SPME-GC)测定水体中邻苯二甲酸酯   总被引:9,自引:0,他引:9  
选用85μm PA纤维,考证了萃取温度、萃取时间、搅拌、离子强度及解析时间等影响因素,最后确立了65℃萃取温度、60min萃取时间、稳定的磁力搅拌、5min解析时间、用带电子捕获检测器的毛细管气相色谱(CGC—ECD)分离测定、外标标准曲线法定量分析水体中邻苯二甲酸酯(PAEs)的方法。该方法具有较好的精密度(RSD≤16%)和较低的检出限(DLDBP=0.003μg/L,DLDEDEHP=0.05μg/L),水样加标回收率在70%~130%之间。用该法测定了长江水样、太湖水样、自来水及蒸馏水的PAEs含量,DBP在0.1~0.4μg/L,DEHP在0.2~1.2μg/L,DMP、DEP、DOP均未检测到。  相似文献   

3.
用2-(2-喹啉偶氮)-5-二乙氨基苯甲酸(QADEAB)与镍的显色反应及Waters Porapak^R Sep-Park固术萃取小柱对显色络合物的固相萃取,建立了测定水样中μg/L级镍的新方法。水样中的镍在pH=8.0的硼酸-磷酸二氢钾缓冲介质中和Tween 80存在下与QADEAB反应生成2:1稳定有色络合物,该络合物可用Waters Porapak^R Sep-Park固相萃取小柱富集,用乙醇洗脱后用光度法测定,可测定水样中μg/L级的镍。方法用于几种环境水样分析,结果令人满意。  相似文献   

4.
新型固相微萃取探头测定工业废水中的甲苯和二甲苯   总被引:9,自引:0,他引:9  
采用溶胶-凝胶方法研制的聚甲基苯基乙烯基硅氧烷/羟基硅油复合涂层的固相微萃取探头及顶空固相微萃取-气相色谱联用技术(HS-SPME-GC),测定了制漆厂排放的工业废水中的甲苯和二甲苯。研究了影响该方法分析灵敏度的各种条件因素:萃取时间和温度,解吸时间和温度及离子强度等。结果表明新探头性能优于商用聚二甲基硅氧烷探头。方法的检出限为0.01μg/L-0.1μg/L,相对标准偏差小于6%;除苯以外线性范围达3个数量级。  相似文献   

5.
固相微萃取-气相色谱-质谱联用分析水中的痕量扑草净   总被引:3,自引:0,他引:3  
研究了固相微萃取-气相色谱-质谱联用测定水中扑草净的方法,采用聚丙烯酸酯(PA)萃取头,对影响固相微萃取萃取效率的萃取时间、搅拌速度、pH值以及盐度等进行了优化。在优化实验条件下,方法线性范围在0.1mg/mL-1000ng/mL之间,检出限为1.5ng/L。用该法分析了合成井水、自来水和湖水样品,回收率在85.4%-89.1%之间,相对标准偏差在1.8%-5.2%之间。本方法适合于水中痕量扑草净的分析。  相似文献   

6.
通过制备磁性金属有机骨架Fe3O4@ZIF-8作为磁性吸附剂,与HPLC-MS/MS联用,建立了磁性固相萃取-高效液相色谱-串联质谱法测定环境水体中痕量磺胺类抗生素残留的分析方法。通过扫描电子显微镜、傅里叶变换红外光谱和X-射线衍射仪对Fe3O4@ZIF-8进行表面形貌、结构和磁强度的表征。结果显示,ZIF-8附着于磁性粒子Fe3O4表面,可以满足磁性固相萃取的要求。对磁性萃取剂用量、吸附时间、样品pH、洗脱时间、洗脱剂种类和pH等萃取条件进行优化。在最优条件下,方法的线性范围为0.05~50μg/L,线性相关系数(R2)均大于0.9971;目标物的检出限为0.06~0.71μg/L,定量限为0.20~2.37μg/L。3个加标水平下得到的加标回收率为78.5%~98.6%,相对标准偏差(RSD)为3.5%~8.9%。  相似文献   

7.
利用自制的活性炭纤维结合固相微萃取-气质联用技术(ACF—SPME/GC~MS)分析了水相中的一丁基三氯锡(MBT,monobutyltin trichloride)。对实验影响因素如萃取温度、离子强度、萃取时间进行了研究。结果表明,该方法的线性范围为0.1~100μg/L,检出限为4.5ng/L,相对标准偏差为8.6%。将ACF—SPME/GC—MS技术用于实际海水样品的分析,取得了理想的效果。  相似文献   

8.
应用可忽略耗损固相微萃取与高效液相色谱联用技术测定了环境水样中双酚A的自由溶解态浓度。为了获得高的灵敏度并减小环境因素(如温度和搅拌等)的影响,采用商品化固相微萃取纤维CW/TPR进行平衡采样。在环境水样常见pH(5~8)、缓冲容量(5~200mmol/L)和盐度(0~500mmol/L)条件下,4h可以达到萃取平衡。100mL样品足以避免样品耗损。以配制在250mmol/L NaCl和125mmol/L磷酸盐溶液(pH6.4)中的双酚A标准溶液进行校准,可以将缓冲液(0~200mmol/L)、盐度(0~500mmol/L)和pH(5.7~8.5)的影响控制在15%偏差范围以内。如需更准确的测定,也可以对样品pH值的影响加以校正。pH为6.4时,方法的线性范围为0.1~250μg/L,检出限为0.03μg/L,相对标准偏差(5μg/L,n=3)为1.1%。采用本方法测定了污水处理厂排水口的双酚A的自由溶解态浓度。  相似文献   

9.
建立了固相微萃取-气相色谱质谱联用测定聚碳酸酯树脂中环境雌激素4-枯基苯酚和双酚A的分析方法。优化了固相微萃取纤维、萃取温度和时间、解吸时间、搅拌速度、pH等萃取条件及衍生化温度和时间、衍生化方式等衍生化条件,并对样品浸泡时间、浸泡温度等进行了研究。方法的线性范围为0.05μg/L~1mg/L,4-枯基苯酚和双酚A的检出限分别为50ng/L和0.5ng/L,相对标准偏差(RSD,n=5)分别为5.2%和1.6%,平均回收率(n=3)在90.50%~107.3%之间,该方法简单、快速、灵敏。  相似文献   

10.
建立了动物组织中沙丁胺醇残留量固相萃取-气相色谱-质谱分析方法。动物组织样品经过葡萄糖醛甙酶酶解后调节pH至9.5,然后用异丙醇/乙酸乙酯混合溶剂液液分配去除杂质,旋转浓缩后用乙酸铵缓冲溶液溶解经SCX固相萃取(SPE)柱净化,洗脱液经氮气吹干后用双三甲基硅基三氟乙酰氨(BSTFA)衍生,采用选择离子模式(86、350、369、440)进行测定,外标法定量。检出限为0.10μg/kg。在添加浓度0.5~5.0μg/kg范围内,平均添加回收率在66.4%~82.4%,相对标准偏差(批内)(CV)在3.5%~5.9%之间;批间(CV)在2.2%~4.8%之间。衍生物的峰面积与样品浓度在0.002~0.50mg/L范围内呈良好的线性关系,线性回归系数大于0.999。  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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