固相萃取/高效液相色谱法测定饮用水中苯并(a)芘及双酚A

建立了饮用水中苯并(a)芘(Bap)和双酚A(BPA)同时测定的固相萃取/高效液相色谱方法。水样中苯并(a)芘和双酚A经ENVI-18固相萃取小柱富集后,采用C18色谱柱分离,以乙腈-水为流动相,梯度洗脱,荧光检测器检测。结果表明,苯并(a)芘和双酚A在0.1~20.0μg/L浓度范围内线性关系良好,相关系数大于0.999,检出限分别为0.2 ng/L和2.0 ng/L,样品加标回收率为86.1%~101%,相对标准偏差为2.9%~4.6%。该方法灵敏度高,选择性好,方便快捷,适用于饮用水中苯并(a)芘和双酚A的测定。     

SPE-LC-MS联用同时测定环境水样中痕量三聚氰胺和灭蝇胺

建立了一种同时测定环境水样中痕量三聚氰胺和灭蝇胺的固相萃取-高效液相色谱-质谱联用(SPE-LC-MS)分析方法。水样经PCX柱固相萃取,以CN柱为分析柱,V(甲醇)∶V(水)=30∶70为流动相,采用电喷雾正离子模式全扫描,三聚氰胺、灭蝇胺的定量离子分别为m/z127,m/z167,获得的最低检出限分别为0.05,0.08μg/L,对不同来源的实际水样加标回收率为85.2%～104.2%,相对标准偏差为1.5%～5.1%。应用该方法测定了湖水、河水、江水等不同基质实际水样。     

在线固相萃取-高效液相色谱同时检测水中双酚A和双酚S

建立在线固相萃取-高效液相色谱法(On-line SPE-HPLC)同时测定水样中双酚A(BPA)和双酚S(BPS)的新方法。水样经过滤,用C18柱在线富集,用Spherigel C18分析柱(250 mm×4.6 mm,5μm)进行HPLC分析,以乙腈-水为流动相梯度洗脱(0~15 min,乙腈-水由70/30(V/V)变为80/20(V/V)),用高效液相色谱-二极管阵列检测器(HPLC-DAD)进行定量分析,检测波长为323 nm。BPA在0.05~5μg/L范围内,BPS在0.07~5μg/L范围内,线性关系良好,相关系数R~20.999。BPA和BPS检测限(LOD)分别为0.017和0.028μg/L,定量限(LOQ)分别为0.033和0.057μg/L。加标0.2μg/L BPA和BPS时,回收率在90%~98%内,相对标准偏差(n=6)在2%~6%内。本法适用于环境水样中BPA和BPS的同时测定。     

高效液相色谱-荧光检测法测定环境水中的苯胺和苯酚

建立了用高效液相色谱荧光检测法同时测定环境水中苯胺和苯酚的分析方法。色谱柱为EclipseXDB C8(4.6mmi.d.×150mm,5μm),流动相为甲醇 磷酸盐缓冲液(0.1mol/L磷酸二氢钾 0 1mol/L磷酸氢二钠,pH6.87)V(甲醇)∶V(磷酸盐缓冲液)=50∶50,流速1 0mL/min,柱温25℃,检测波长0minλex/λem=230/340nm(测定苯胺),3.5minλex/λem=215/300nm(测定苯酚)。测定苯胺的线性范围0.2～120ng,r=0.9999,检出限0.01ng;测定苯酚的线性范围0.4～500ng,r=0.9998,检出限0.02ng,回收率98.1%～101.2%。该方法已用于对环境水中苯胺和苯酚的测定。     

固相萃取法测定水中短链氯化石蜡

建立了固相萃取法结合气相色谱-低分辨率电子捕获负化学源质谱(GC/ECNI-MS)测定水样中短链氯化石蜡(SCCPs)的方法。选取了4种不同填料的商品化固相萃取柱,对淋洗溶剂、洗脱溶剂、洗脱溶剂体积等实验参数进行了优化。经过优化的实验条件为:Agilent Bond Elut-C_(18)固相萃取柱分别用3 mL正己烷、3 mL甲醇、3 mL Milli-Q纯水预淋洗并活化,上样后,用3 mL 10%(V/V)甲醇淋洗,3 mL正己烷-二氯甲烷(1∶1,V/V)洗脱。本方法的检出限和定量限分别为18 ng/L和60 ng/L。1μg/L加标水平下回收率为90%~130%,相对标准偏差低于±10%。采用本方法对北京20个水体样品中的短链氯化石蜡水平进行了测定,浓度范围为LOD~682 ng/L,在检测到SCCPs的18个样品中SCCPs的均值为216 ng/L。     

固相萃取-高效液相色谱法测定水中BPA、NP和OP含量

采用国产新型D4020大孔吸附树脂自制固相萃取柱,研究了柱长、上样速度、样品溶液的pH、盐浓度等因素对壬基酚、辛基酚和双酚A吸附率的影响,确定了最佳固相萃取条件,建立了固相萃取-高效液相色谱测定水中痕量壬基酚、辛基酚和双酚A的分析方法.该法双酚A、壬基酚和辛基酚的检出限分别为0.432 μg/L、0.998 μg/L和1.336 μg/L,回收率为91%～96%,相对标准偏差(RSD)为1.5%～5.6%.方法简便快速、成本低廉,灵敏度高,准确度好,用于实际水样分析,取得满意结果.     

一种简便的双酚A高效液相色谱检测方法

建立了用紫外检测器高效液相色谱法(HPLC)代替荧光检测器HPLC法检测去除双酚A过程中,双酚A残留量的分析方法.采用Symmetry C18柱(5μm,4.6 mm i.d.×150 mm),以V(甲醇):V(水):V(乙腈):V(四氢呋喃)=40:44:8:8为流动相,流速为1.0 mL/min,紫外检测波长为276 nm,柱温为室温,进样量50μL.双酚A在0.500～20.0 mg/L范围内,峰面积与质量浓度呈良好的线性关系,相对标准偏差RSD为1.5%(n=6),回收率在99.98%～100.13%之间,该方法简便、准确、价廉,可用于去除环境中双酚A的跟踪检测.     

三相中空纤维膜液相微萃取-高效液相色谱法测定水中痕量双酚A

建立了三相中空纤维膜液相微萃取-高效液相色谱(HF-LPME-HPLC)方法,用于分析测定水中痕量双酚A的含量.设计了三相中空纤维膜液相微萃取系统,优化的HP-LPME最佳萃取条件为:萃取剂为正辛醇,接受相NaOH浓度为0.09 mol/L,样品溶液pH=4.0,NaC1加入量为30 g/L,搅拌速度为900 r/min,萃取时间为60 min.萃取后取20 μL接受相进行色谱分析.在最佳萃取条件下,方法的线性范围为0.5～200 μg/L(r＞ 0.999),检出限(信噪比为3)为0.2 μg/L;富集因子为241;方法RSD＜3.2％ (n=3).在实际环境水样中添加5,20和50μg/L的双酚A标准物质,加标平均回收率为92.8％～101.9％.表明本方法可用于水中痕量双酚A的快速准确测定.     

表面活性剂辅助-凝固-漂浮分散液液微萃取/高效液相色谱法测定环境水样中酚类化合物

建立了表面活性剂辅助-凝固-漂浮分散液液微萃取(SA-DLLME-SFO)/高效液相色谱法同时测定环境水样中4种酚类化合物的分析方法。SA-DLLME-SFO实验中选用十二醇为萃取剂,Tween 20为分散剂,考察了萃取剂和非离子表面活性剂的体积、萃取时间、离心时间和盐效应等因素对萃取效率的影响。结果表明:对硝基苯酚、对甲酚、对溴酚和双酚A的检出限分别为0.13,0.13,1.02,0.25 ng/m L;对硝基苯酚、对甲酚和双酚A的线性范围为2~4 000 ng/m L,对溴苯酚的线性范围为10~4 000 ng/m L;加标浓度为0.2,0.8μg/m L时,4种酚类化合物的回收率为96.6%~105%,相对标准偏差(RSD,n=5)为1.9%~4.9%。该方法可用于池塘水和湖水等天然水体中对硝基苯酚、对甲酚、对溴酚和双酚A的测定。     

流动注射在线预富集-高效液相色谱法测定水中的4-壬基酚和双酚A

建立了以香烟过滤嘴作吸附剂,在线固相萃取(SPE)与高效液相色谱(HPLC)联用测定水中双酚A(bisphenol A,BPA)和4-壬基酚(4-nonylphenol,4-NP)的方法。对于高效液相(HPLC)在线固相萃取而言,采用内置香烟过滤嘴的预富集圆形柱来代替传统的高效液相仪中的注射管进样环用于在线固相萃取。通过流动注射仪将样品分析物负载加入到预富集柱中,随后采用V(甲醇):V(H2O)=93:7混合液为洗脱剂对富集的样品分析物进行洗脱。采用Eclipse XDB-C18色谱柱,V(甲醇):V(H2O)=93:7混合液为流动相,流速为1.0mL/min,紫外检测波长为227nm,保留时间定性,外标法定量。双酚A在0.005～0.8mg/L、4-壬基酚在0.04～8.0mg/L范围内,两者峰面积与浓度呈线性关系,相关系数分别为0.9985和0.9983,检出限(S/N=3)分别为2.1和10.0μg/L,富集倍数分别为816和346倍。对标准混合物(BPA:0.2mg/L;4-NP:2.0mg/L)重复测量11次的相对标准偏差为2.3%和1.5%。本方法用于当地河流水样中BPA和4-NP的测定,回收率为93.2%～105.4%。     

多环芳二酐型聚酯亚胺膜的透气性能

多环芳二酐型聚酯亚胺膜的透气性能李悦生，丁孟贤，徐纪平（浙江大学高分子科学与工程研究所，杭州，３１００２７）（中国科学院长春应用化学研究所）关键词聚醚酰亚胺，聚酯酰亚胺，膜，透气性通常的聚酰亚胺加工性能较差，在芳环二酐的苯环间引入醚键等柔性基团后，其...     

Determination and study on residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil

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).     

微量元素与疾病诊断治疗的研究现状及展望

对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述，包括：微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。     

Conformations and steric and stacking interactions of trisubstituted ureas and thioureas with alkyl and phenyl groups

The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R₂UPh type and -thioureas of the R₂TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.     

Ti-V基储氢合金及其氢化物的物相结构与组分优化设计

Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB₅型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。     

钒与糖代谢及糖尿病

微量元素钒作为生物体内必需元素，经证实有很重要的生理学功能，与机体糖代谢有十分密切的关系，且能降低糖尿病动物模型的高血糖，极有可能被开发为治疗糖尿病的药物。     

Ferrocene and ferrocenium modified clays and their styrene and EVA composites

In this work, ferrocene- and ferrocenium-containing salts were employed to modify montmorillonite. X-ray measurements show an increase in the interlayer spacing upon clay modification, which means that the larger and more organophilic cations were inserted into the gallery space of montmorillonite. Attempts to prepare nanocomposites of polystyrene and ethylene vinyl acetate copolymers lead to immiscible systems; the morphology of these systems was elucidated with TEM, XRD and cone calorimetry. The thermal stability of the composites is greater than that of the virgin polymer.     

Synthesis and Optical and Redox Properties of Symmetric and Asymmetric BODIPYs

Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.     

Synthesis of Tyrosol and Hydroxytyrosol Glycofuranosides and Their Biochemical and Biological Activities in Cell-Free and Cellular Assays

Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.