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1.
包建民  马志爽  孙莹  王勇尊  李优鑫 《色谱》2012,30(8):798-803
以含硅藻土的复合材料为支撑介质,开发了一种独特的支撑液液萃取柱;以一系列酸性、碱性和中性水溶液样品为模型化合物,结合高效液相色谱法(HPLC)对该萃取柱进行了系统评价,同时将其用于复杂基质样品的分析。结果表明: 经该支撑液液萃取柱预处理的苯甲酸、对硝基苯胺和对羟基苯甲酸甲酯水溶液的萃取回收率分别为90.6%、98.1%和97.7%,远超过对应样品经传统液液萃取法处理后的回收率(分别为71.9%、81.9%和83.9%)。对于复杂基质样品的分析,如雪碧中的防腐剂苯甲酸以及牛血清中的中性药物醋酸地塞米松、碱性药物马来酸氯苯那敏及酸性药物吲哚美辛等,样品的加标回收率均在80%和110%之间,相对标准偏差(RSD)均小于15%,符合生物样品的分析要求,且未出现传统液液萃取技术中常见的问题(如乳化现象)。所开发的支撑液液萃取柱具有快速、简单、耐受性好、易于实现自动化和高通量的特点,具有广泛的应用前景。  相似文献   

2.
土壤中64种痕量半挥发性有机污染物的分析方法研究   总被引:1,自引:0,他引:1  
利用超声提取技术将土壤中的半挥发性有机污染物(SVOC)提取出来, 经旋转蒸发浓缩至一定体积后, 用ODSC18柱净化, 再用氮吹浓缩后, 取1.0 μL注入气相色谱中, 用DB-5 ms柱分离, 用气相色谱质谱仪(GC-MS)进行定性定量分析. 本方法研究土壤中64种半挥发性有机污染物, 其中包括苯系物、苯酚类、苯胺类、硝基芳香烃类、氯代芳烃类、多环芳烃类和酞酸酯类等物质的提取、净化方法以及回收率、精密度和检测限的测定. 该方法回收率为52.5%~105%.  相似文献   

3.
采用液液萃取法富集水体中的有机污染物,以气相色谱-质谱和Compound composer软件进行筛查和半定量计算,同时以气相色谱-质谱法在选择离子模式下对Compound composer软件的半定量结果进行验证,结果表明除3-氨基苯酚、豆甾醇和β-谷甾醇外,其它物质的回收率在74%~102%之间,保留时间偏差为-0.158 ~0.049 min,对添加量为1.0μg目标物的水样半定量,结果偏差在-0.48~0.62 μg之间.在无标准样品的条件下,利用Compound composer软件及其自带含近千种化合物标准曲线的数据库,对江苏省南通、苏州和无锡三市的地表水环境样品进行监测,筛查其中主要的有机污染物,并进行半定量计算.三市地表水样中共检出47种有机污染物.2,6-二叔丁基-4-甲基苯酚为检出浓度最高的化合物,其浓度达140 μg·L-1,酞酸酯类和多环芳烃类物质普遍存在,其单体浓度范围分别为1.7~48μg·L-1和0.13 ~9.6 μg· L-1.依照GB3838-2002《地表水环境质量标准》,三市地表水体中酞酸酯类严重超标,水体中总有机物污染状况应引起关注.  相似文献   

4.
β-环糊精交联聚合物的合成及其在水处理中的应用   总被引:20,自引:0,他引:20  
以环氧氯丙烷为交联剂,在碱性介质中将β-环糊精固载化,合成了不溶于水的β-环糊精交联聚合物,同时考察了β-环糊精交联聚合物对模拟水样中的微污染物(无机重金属离子及有机酚类、胺类)的吸附性能。实验结果表明:β-环糊精交联聚合物对无机重金属离子(Pb^2 ,Cu^2 ,Cd^2 ,Zn^2 )及苯酚、苯胺的去除效果良好,前者的去除率达到83.60%以上,其中Pb^2 的去除率高达95.62%,苯酚、苯胺的去除率达到95%以上。  相似文献   

5.
基于全二维气相色谱-四极杆飞行时间质谱(GC × GC-Q-TOF MS)建立了土壤样品中24种有机磷 和20种有机氯农药残留的快速同时检测方法,样品经索氏提取后直接采用全二维气相色谱进行分离,有效实 现了杂质与目标物的完全族分离效果。以24种有机磷和20种有机氯农药的高分辨精确质量特征离子进行定 量分析,结果表明,44 种农药均在 20~3 000 μg/L 质量浓度范围内呈线性关系,相关系数(r 2 )为 0. 990 3~ 0. 999 9,检出限(LOD)为 0. 3~7. 9 μg/L;方法的平均回收率为 93. 0%,平均相对标准偏差(RSD,n = 5)为 6. 9%。该文可为土壤中农药残留的高通量快速筛查提供方法参考。  相似文献   

6.
根据盐效应原理 ,研究了在pH =7 0± 0 5的中性介质中、大量氯化钠存在条件下加盐蒸馏 ,同时分离、富集水中微量苯酚和苯胺的实验方法。结果表明 ,2 50ml水样加入 1 50gNaCl,只须接取最初 50ml(水样体积的 1 5)馏出液 ,就可获得 93%左右的苯酚和 91 %以上的苯胺回收率。若同时辅之以紫外 4阶导数光谱法进行测定 ,经回收率校正后 ,可准确测定水中微量苯酚和苯胺。此方法可应用于各类污水中酚、胺的同时分离测定。  相似文献   

7.
用支持向量回归(SVR)结合分光光度法对苯酚、苯胺、苯甲酸进行了同时测定.在230~300 nm的波长范围内,用SVR方法建立校正模型,用留一交叉验证的方法优化SVR方法建模,并对苯酚、苯胺、苯甲酸的模拟样品进行了测定.苯酚、苯胺、苯甲酸的预测结果的回收率在98.1%~101.1%之间.  相似文献   

8.
在波长范围200~400nm测定苯酚、苯胺和苯甲酸混合液的吸收光谱,用离散小波变换(DWT)对光谱数据进行处理,再用支持向量回归SVR方法进行建模,建立了离散小波变换一支持向量回归方法(DWT—SVR)。方法用于模拟样品和污染水样中苯酚、苯胺和苯甲酸的同时测定,结果满意。  相似文献   

9.
建立小体积液液萃取-气相色谱-三重四极杆串联质谱法测定地下水中32种半挥发性有机污染物(SVOCs)的方法。采用2 mL二氯甲烷和正己烷混合溶剂(体积比为1∶1)加入到20 mL水样中,添加2 g NaCl,涡旋萃取60 s,经DB-5MS UI色谱柱(30 m×0.25 mm,0.25μm)分离,SRM模式检测,内标法定量。32种SVOCs的质量浓度在0.5~20μg/L范围内与色谱峰面积具有良好的线性关系,相关系数均大于0.995,方法检出限为0.002~0.06μg/L。样品加标回收率为72.5%~129%,测定结果的相对标准偏差为0.65%~21.1%(n=6)。该方法样品处理简单快捷,所需水样和有机试剂体积较少,能够满足地下水中32种SVOCs的高效测定。  相似文献   

10.
液相色谱-串联质谱法快速测定水及鱼肉中的苯胺   总被引:1,自引:0,他引:1  
为快速准确测定水及鱼肉中的苯胺,采用乙腈提取、高效液相色谱-串联质谱测定,建立了水及鱼肉中苯胺的快速测定方法。水样与乙腈以4:1的体积比混合,1.00 g鱼肉中加入2.00 mL乙腈,涡旋提取1 min,水样和鱼肉样品的提取液离心5 min后取上清液测定。以C18柱为分离柱,乙腈-0.5%(v/v)甲酸水溶液(85:15,v/v)为流动相,目标物质在3 min内分离。在0.5~500 μg/L范围内,苯胺峰面积与内标峰面积之比与质量浓度的线性关系良好(R2>0.999)。基质加标试验结果表明,苯胺在水中的回收率分别为93.7%(加标水平为40 ng)和86.7% (加标水平为400 ng),苯胺在鱼肉中的回收率分别为96.8%、 92.6%和81.8%(加标水平分别为5、50和500 ng),相对标准偏差在1.5%~9.2%之间。水样和鱼肉样品中苯胺的检出限分别为0.50 μg/L和1.00 μg/kg,定量限分别为1.00 μg/L和2.00 μg/kg。应用该方法测定了从受苯胺污染的水库中采集的13份水样和12份鱼肉样品,结果表明,水和鱼肉中苯胺的最大含量分别为1943.6 μg/L和60.8 μg/kg。本方法快速、准确,适用于水和鱼肉中苯胺的快速测定。  相似文献   

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We review our research on the synthesis and study of the physical and biological properties of furyl- and thienylgermatranes and -silatranes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 725–732, June, 1992.  相似文献   

13.
The use of the insect cell/baculovirus expression system for producing recombinant proteins of bacterial, plant, insect, and mammalian origin has become widespread. The popularity of this eukaryotic expression system is due to many factors, including (1) potentially high protein expression levels, (2) ease and speed of genetic engineering, (3) ability to accommodate large DNA inserts, (4) protein processing similar to higher eukaryotic cells (e.g., mammalian cells), and (5) ease of insect cell growth (e.g., suspension growth). The following review of the literature discusses two engineering aspects of recombinant protein synthesis by insect cell cultures: bioreactor scale-up and insect cell line selection. Following this review patent abstracts and additional literature pertaining to expression of recombinant proteins in insect cell culture are listed.  相似文献   

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The aromaticity and antiaromaticity of the ground state (S 0), lowest triplet state (T 1), and first singlet excited state (S 1) of benzene, and the ground states (S 0), lowest triplet states (T 1), and the first and second singlet excited states (S 1 and S 2) of square and rectangular cyclobutadiene are assessed using various magnetic criteria including nucleus-independent chemical shifts (NICS), proton shieldings, and magnetic susceptibilities calculated using complete-active-space self-consistent field (CASSCF) wave functions constructed from gauge-including atomic orbitals (GIAOs). These magnetic criteria strongly suggest that, in contrast to the well-known aromaticity of the S 0 state of benzene, the T 1 and S 1 states of this molecule are antiaromatic. In square cyclobutadiene, which is shown to be considerably more antiaromatic than rectangular cyclobutadiene, the magnetic properties of the T 1 and S 1 states allow these to be classified as aromatic. According to the computed magnetic criteria, the T 1 state of rectangular cyclobutadiene is still aromatic, but the S 1 state is antiaromatic, just as the S 2 state of square cyclobutadiene; the S 2 state of rectangular cyclobutadiene is nonaromatic. The results demonstrate that the well-known "triplet aromaticity" of cyclic conjugated hydrocarbons represents a particular case of a broader concept of excited-state aromaticity and antiaromaticity. It is shown that while electronic excitation may lead to increased nuclear shieldings in certain low-lying electronic states, in general its main effect can be expected to be nuclear deshielding, which can be substantial for heavier nuclei.  相似文献   

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Under investigation is the structure and process that gives rise to hard-soft behavior in simple anionic atomic bases. That for simple atomic bases the chemical hardness is expected to be the only extrinsic component of acid-base strength, has been substantiated in the current study. A thermochemically based operational scale of chemical hardness was used to identify the structure within anionic atomic bases that is responsible for chemical hardness. The base's responding electrons have been identified as the structure, and the relaxation that occurs during charge transfer has been identified as the process giving rise to hard-soft behavior. This is in contrast the commonly accepted explanations that attribute hard-soft behavior to varying degrees of electrostatic and covalent contributions to the acid-base interaction. The ability of the atomic ion's responding electrons to cause hard-soft behavior has been assessed by examining the correlation of the estimated relaxation energies of the responding electrons with the operational chemical hardness. It has been demonstrated that the responding electrons are able to give rise to hard-soft behavior in simple anionic bases.  相似文献   

19.
A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg?1, the maximum residue level of European Union for quizalofop-p-ethyl).  相似文献   

20.
The P-anilino-P-chalcogeno(imino)diazasilaphosphetidines [Me(2)Si(mu-N(t)Bu)(2)P=E(NHPh)] (E = O (3), S (4), Se (5), N-p-tolyl (6)) were synthesized by oxidizing the P-anilinodiazasilaphosphetidine [Me(2)Si(N(t)Bu)(2)P(NHPh)] (2) with cumene hydroperoxide, sulfur, selenium, and p-tolyl azide, respectively. The lithium salt of 4 reacted with thallium monochloride to produce ([Me(2)Si(mu-N(t)Bu)(2)P=S(NPh)-kappaN-kappaS]Tl)(7), which features a two-coordinate thallium atom. Treatment of 4-6 with AlMe(3) gave the monoligand dimethylaluminum complexes ([Me(2)Si(mu-N(t)Bu)(2)P=E(NPh)-kappaN-kappaE]AlMe(2)) (E = S (8), Se (9), N-p-tolyl (10)), respectively. In these complexes the aluminum atom is tetrahedrally coordinated by one chelating ligand and two methyl groups, as a single-crystal X-ray analysis of 8 showed. A 2 equiv amount of 4-6 reacted with diethylzinc to produce the homoleptic diligand complexes ([Me(2)Si(mu-N(t)Bu)(2)P=E(NPh)-kappaN-kappaE](2)Zn)(E = S (11), Se (12), N-p-tolyl (13)). A crystal-structure analysis of 11 revealed a linear tetraspirocycle with a tetrahedrally coordinated, central zinc atom.  相似文献   

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