香水中邻苯二甲酸二乙酯的直接质谱分析研究

建立了香水中邻苯二甲酸酯的快速检测方法。采用电喷雾萃取电离技术（EESI）对5种不同品牌香水中邻苯二甲酸二乙酯(DEP)进行了快速直接质谱分析。结果表明：电喷雾萃取电离质谱（EESI-MS）法能够定性定量分析香水中DEP,线性范围为20~1 000 μg/L,线性相关系数R²为0.988 9,检出限为0.39 μg/L,定量限为5.47 μg/L,回收率为94.8%~103.4%,相对标准偏差为1.5%~4.1%。该方法具有检出限低、准确度高、分析速度快（单个样品的测定时间小于30 s）、无需复杂的样品预处理等优点,可为香水中邻苯二甲酸酯的快速检测提供方法参考。     

在线凝胶色谱-串联三重四极杆质谱法测定大豆油中42种农药残留

建立了在线凝胶色谱-串联三重四极杆质谱（GPC-GC-MS/MS）法测定大豆油中的42种农药残留。采用在线凝胶色谱进行在线净化,除去大豆油中大部分油脂,有效缩短样品前处理时间;结合多反应监测（MRM）采集方式,可减少基质干扰,提高方法的选择性。结果表明：在1~50 μg/L浓度范围内,大部分农药的线性相关系数均在0.999以上;方法检出限为0.02~2.59 μg/kg,方法定量限为0.08~8.62 μg/kg;在10、50、300 μg/kg加标浓度下,农药的加标回收率在70.4%~119%之间。以α-666等11种农药为例,比较了GPC-GC-MS/MS法、GPC-GC/MS法、GC-MS/MS法的实验结果,发现采用GPC-GC-MS/MS法的MRM数据采集模式测定大豆油中农药残留具有良好的抗基质干扰能力,可获得最低的方法检出限及最高的回收率。该方法操作简单、灵敏度高、稳定性好,可用于大豆油中农药残留的测定,也适用于复杂基质中痕量农药残留的定性和定量分析。     

同位素稀释-气相色谱-串联质谱法测定化妆品中10种合成麝香

建立了同位素稀释-气相色谱-串联质谱（GC-MS/MS）法同时测定化妆品中10种合成麝香（SMs）,并对方法前处理和仪器条件进行了优化。样品加入氘代同位素内标后,以饱和氯化钠-正己烷溶液体系超声提取,提取液经氮吹浓缩定容后,采用极性毛细管柱VF-WAXms（30 m×0.25 mm×0.25 μm）分离,以多反应监测模式（MRM）测定,内标校正标准曲线法定量。结果表明：10种合成麝香的线性范围为1.0～100.0 μg/L,相关系数均大于0.99,定量限为1.0～8.0 μg/kg。加标回收率在92.5%～102.0%之间,相对标准偏差（RSD）均小于5%。本方法简便、准确、快速、灵敏,可同时检测化妆品中10种合成麝香成分。     

UPLC-QTOF-MS测定沉积物中7种新型污染物

本研究建立了固相萃取（SPE）-超高效液相色谱-四极杆飞行时间质谱（UPLC-QTOF-MS）检测沉积物中水杨酸（SA）、萘普生（NAX）、布洛芬（IBU）、酮洛芬（KET）、双氯芬酸（DIC）、降固醇酸（CLO）和三氯生（TRI）7种新型污染物的分析方法。样品用甲酸 丙酮溶液（1∶99,V/V）超声提取,MAX阴离子固相萃取柱净化,UPLC-QTOF-MS测定。在优化的实验条件下,7种新型污染物在2~500 μg/L浓度范围内线性关系良好,线性相关系数均大于0.99,方法检出限（S/N=3）为0.5~0.6 μg/kg,方法定量限（S/N=10）为1.5~2.0 μg/kg（均以干重计）,3个添加浓度水平（低、中、高）的回收率为87.8%~105.1%,相对标准偏差（n=5）为3.1%~12.2%。利用该方法对广州市流溪河段表层沉积物样品进行分析,检出4种污染物,最高浓度范围为6.51~12.26 μg/kg（以干重计）。该方法高效、准确,适用于沉积物中7种污染物的测定。     

碱液处理-活性炭柱固相萃取结合GC-MS/MS法检测鱼干、虾皮和虾仁中8种N-亚硝胺

建立了碱液处理-活性炭柱固相萃取结合气相色谱-串联质谱联用（GC-MS/MS）技术检测鱼干、虾皮和虾仁中N-亚硝基二甲胺(NDMA)、N-亚硝基甲乙胺(NMEA)、N-亚硝基二乙胺(NDEA)、N-亚硝基二正丙胺(NDPA)、N-亚硝基哌啶(NPIP)、N-亚硝基吡咯烷(NPYR)、N-亚硝基吗啉(NMOR)和N-亚硝基二正丁胺(NDBA)等有害物质。以NDMA-d6、NDPA-d14和NPYR-d8为内标, 用Ba(OH)₂溶液于80 ℃处理样品1 h,离心上清液,经Sep-Pak^® plus AC-2活性炭小柱富集净化,DB-WAXUI（30 m×250 μm×0.25 μm）色谱柱分离,质谱多反应监测(MRM)模式检测。结果表明,在1~200 μg/L浓度范围内,8种N-亚硝胺的线性关系良好,R²＞0.998;检出限为0.03~0.25 μg/kg, 定量限为0.10~0.85 μg/kg,添加回收率为71.3%~119.0%（除NDBA在高添加水平时略低,为52.1%~69.0%）,相对标准偏差为0.65%~15.4%。将该方法用于23种实际样品检测,在所有样品中均检出NDMA,且含量相对较高,其他N-亚硝胺仅部分检出,含量相对较低。该方法操作简单、便于高通量分析、环境友好、定性定量可靠,可为水产品中N-亚硝胺类物质的检测提供参考。     

Sin-QuEChERS结合UPLC-MS/MS同时检测茶叶中10种有机磷农药残留

基于茶叶样品基质复杂的特点,采用简易的基质分散净化（Sin-QuEChERS）法对样品前处理技术加以改进,并结合超高效液相色谱-串联质谱（UPLC-MS/MS）技术,建立了同时检测茶叶中10种有机磷农药残留的分析方法。与传统的样品预处理方法相比,该方法在保证重复性和稳定性的前提下,具有操作简单、省时省力、普适性好、灵敏度高等优点。在优化的Sin-QuEChERS方法提取净化条件和UPLC-MS/MS检测条件下,可将样品前处理时间控制在10 min以内,使每个样品的分析在0.5 h内完成。结果表明：10种有机磷农药的线性范围为1~500 μg/L,检出限为0.08~1.38 μg/kg,定量限为0.27~4.60 μg/kg;在不同的加标水平下,平均回收率在71.6%~115.0%之间,RSD小于14.5%,与国家标准方法的检测结果接近。将该方法应用于检测空白茶叶加标样品和20种市售茶叶中有机磷农药,验证了方法的可行性。该研究可为快速、简易、准确地评价茶叶中多种有机磷类农药的质量安全提供方法参考。     

改进QuEChERS-超高效液相色谱-串联质谱法同时测定甘草中86种农药残留

建立了QuEChERS结合超高效液相色谱-串联质谱（UPLC-MS/MS）法同时测定甘草中86种农药残留,比较了9种不同QuEChERS方法的净化效率和回收率,结果表明,无石墨化碳黑（NGCB）QuEChERS方法效果最佳。在依赖保留时间的多反应监测模式（scheduled MRM）下,采用UPLC-MS/MS法对农药进行定量。86种农药的线性相关系数（r）均大于0.991 3,检出限为0.2~9 μg/kg。在3个（10、50、100 μg/kg）添加水平下,86种农药的回收率为65.0%~129.4%,相对标准偏差（RSD,n=6）为1.0%~19.3%。采用该方法对市场上收集的64批甘草样品进行测定,检出17种农药。该方法可为准确、高效、经济地检测甘草中目标物提供参考。     

高分离快速液相色谱-四极杆飞行时间质谱法检测人参皂苷Re在大鼠体内的分布

建立了高分离快速液相色谱-四极杆飞行时间质谱（RRLC-Q-TOF MS）法检测大鼠尾静脉注射人参皂苷Re（G-Re）后,不同组织（心、肝、脾、肺、肾、脑）中G-Re的分布情况。样本经蛋白沉淀处理,Supelco Ascentis® Express C18色谱柱（50 mm×3.0 mm×2.7 μm）分离,采用含0.1%甲酸的水溶液（A）-乙腈（B）为流动相,梯度洗脱,以人参皂苷Rc（G-Rc）作为内标,在电喷雾负离子模式下检测。结果表明：组织匀浆标准曲线的线性范围为10~20 000 μg/L,线性关系良好（r>0.99）,最低检出限（S/N=3）为3 μg/L,最小定量限为10 μg/L;准确度、日内和日间精密度、提取回收率均符合生物样品的分析要求。大鼠尾静脉注射20 mg/kg G-Re溶液后,在大鼠体内不同组织中均能检测到G-Re,主要分布在肺、脾、肾、心、脑、肝等器官,其中在肺中分布最多,在肝中分布最少。该方法简单、灵敏、快速、检出限低,适用于检测人参皂苷Re在生物体内的分布。     

QuEChERS/UPLC-MS/MS法同时测定梅花鹿鹿茸中36种兽药残留

采用QuEChERS前处理技术,建立了UPLC-MS/MS法同时测定梅花鹿鹿茸中36种兽药残留。鹿茸样品以乙腈-乙酸乙酯（8∶2,V/V）为提取剂,以150 mg 乙二胺基-N-丙基、100 mg C18与70 mg中性氧化铝为净化剂。采用Acquity BEH C18色谱柱（2.1 mm×100 mm×1.7 μm）分离,25 mmol/L甲酸乙腈溶液和12.5 mmol/L甲酸水溶液为流动相进行梯度洗脱,电喷雾正离子多反应监测模式检测。结果表明：36种兽药在0.1~50 μg/L范围内的线性关系良好,相关系数R²均大于0.993,检出限（LOD）为0.08~1 μg/kg,定量限（LOQ）为0.3~3 μg/kg。向空白样中分别添加浓度为2、5、10 μg/kg的36种兽药,平均加样回收率为77.8%~107.6%,相对标准差（RSD）均小于10%。该方法具有操作简便、净化效果显著、灵敏度高、准确性好、检出限低等优点,可用于梅花鹿鹿茸中36种兽药残留的检测。     

超高效液相色谱-串联质谱法测定鱼中孔雀石绿、结晶紫及其代谢物残留量

采用超高效液相色谱-串联质谱（UPLC-MS/MS）法测定鱼中孔雀石绿（MG）、隐色孔雀石绿(LMG)、结晶紫（CV）、隐色结晶紫(LCV)残留。样品加入内标,经乙腈涡旋提取、离心、中性氧化铝柱去除脂肪后,氮吹近干,V(乙腈)∶V(5 mmol/L醋酸铵)=50∶50的溶液定容,上机测定。MG、CV及其代谢物在4.0 μg/L质量浓度范围内有良好的线性关系,MG、LMG、CV的检出限为0.01 μg/kg,LCV的检出限为0.06 μg/kg。在空白样品中分别添加0.25、2.0 μg/kg混合标准溶液和2.0 μg/kg内标溶液进行回收率实验,平均回收率在81.4%~97.8%之间,相对标准偏差RSD（n=6）在5.9%~11.2%之间。对109批次实际鱼样进行检测,4种物质均有不同程度的检出。该方法能够灵敏、准确、可靠的测定鱼中MG、LMG、CV、LCV残留,为鱼类水产品养殖、流通及使用环节的市场监管提供参考依据。     

Fluorescence recognition of proteinaceous binders in works of art by a novel integrated system of investigation

Fluorescence microscopy and microspectrofluorometry are important tools in the characterization and identification of proteins, offering a great range of applications in conservation science. Because of their high selectivity and sensitivity, the combination of these techniques can be exploited for improved recognition and quantification of proteinaceous binders in paintings and polychromed works of art. The present article explores an analytical protocol integrating fluorescence microscopy and fluorometry for both identification and mapping of proteinaceous binders (in particular egg and glues) in paint samples. The study has been carried out on historically accurate reconstructions simulating the structure and composition of tempera and oil paints containing these binders. To assess the spatial distribution of specific proteins within the paint layers, cross‐sections from the reconstructions were analyzed by fluorescence imaging after staining with an exogenous fluorophore. Reference fluorescence spectra for each layer were acquired by a multichannel spectral analyzer and compared after Gaussian deconvolution. The results obtained demonstrated the effectiveness of the integrated protocol, highlighting the potential for the use of fluorescent staining coupled with microspectrofluorometry as a routine diagnostic tool in conservation science. The current work creates a set of fully characterized reference samples for further comparison with those from actual works of art. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.     

气相色谱-串联质谱法测定蛋和蛋制品中氟虫腈及其代谢物残留量

建立了气相色谱-串联质谱法（GC-MS/MS）检测蛋和蛋制品中氟虫腈及其代谢物氟甲腈、氟虫腈硫醚和氟虫腈砜的残留量。蛋和蛋制品经水稀释,涡旋混合均匀;加入0.1%冰醋酸-乙腈溶液和氯化钠,经充分涡旋和振摇后,对样品进行超声提取、离心、提取上层清液;残渣用0.1%冰醋酸-乙腈溶液再提取1次,合并2次提取得到的上清液,浓缩;用乙腈溶解残渣,分散固相萃取（N-丙基乙二胺、石墨化碳黑和十八烷基硅烷）净化后,用气相色谱-串联质谱法测定,外标法定量;同时对提取溶剂、提取方式和分散固相萃取剂进行了优化。结果表明：4种化合物在2~100 μg/L范围内的线性关系良好,相关系数R²大于0.99,定量限为1.0 μg/kg。在1.0、2.0、4.0、20.0 μg/kg加标水平下,氟虫腈及其代谢物的回收率为72.0%~109.5%,相对标准偏差小于16.0%。该方法准确、简单、快速,可用于蛋及蛋制品中氟虫腈及其代谢物的同时测定。     

Investigation of glue-bonding process on assembly accuracy

The effect of assembly accuracy due to the displacement of glue-bonding processes using different types of glues and bonding configuration has been investigated systematically using a multi-dimensional capacitance position monitoring system with resolution in around 10 nm. In our study, we observe that an order of magnitude difference in bonding position accuracy may result using different bonding conditions and glue. Our analysis shows while the shrinkage of glue may play an important factor, other factors have to be taken into account in order to get the optimum condition for the glue bonding process. Displacement of less than 0.1 μm level has been demonstrated for a 4-sided side bonding process using UV glue. This level of accuracy is as much as an order of magnitude better than the result obtainable by the commonly used screwing fastening process.     

Analysis of asphaltic binders modified with PPA by surface techniques

Samples of unmodified and modified asphalt binders containing 1% polyphosphoric acid were studied. Fourier‐transform infrared spectroscopy was used to evaluate the structural indices of the functional groups present in the samples and the results indicated there was a strong interaction between the polyphosphoric acid and oxygenated species. Contact angle measurements indicated that adhesion of the binder to the aggregate depended on the polyphosphoric acid content. Atomic force microscopy was used to relate features observed on the surface of the asphalt binder 50/70, with their local mechanical properties such as stiffness and elasticity. It was observed that the surface of the sample containing 1% polyphosphoric acid provides stiffness values lower than the unmodified asphalt binder.     

Effect of two different rubbers as secondary binders on the friction and wear characteristics of non-asbestos organic (NAO) brake friction materials

Binder provides structural integrity by holding all ingredients in the composition of a brake friction material. The modified binders have played a major role in improving the frictional performance and thermal resistance of the friction material. The present research work evaluates the influence of secondary binders (Nitrile Butadiene rubber (NBR) and Styrene Butadiene rubber (SBR)) on the tribological performance of the friction material using a full-scale inertia brake dynamometer as per JASO C406 standard. Three brake pads were developed by varying the type and composition of secondary rubber binder (5%NBR, 5%SBR and 2.5%NBR + 2.5%SBR) with rest of the ingredients kept unaltered. It was found that the quantity of SBR rubber powder present as secondary binder improved dry and wet recovery. Friction coefficient (μ) exhibited better stability during the fade with the inclusion of both the rubber powders. The friction material with the inclusion of both the NBR and SBR rubber powders exhibited overall better performance than compared to the inclusion of only one secondary binder rubber in the composition. The worn-out surface of the developed friction materials and the counter discs were characterised using FESEM.     

Studies of the microstructure of polymer-modified bitumen emulsions using confocal laser scanning microscopy

Polymer-modified bitumen emulsions present a safer and more environmentally friendly binder for enhancing the properties of roads. Cationic bitumen emulsion binders containing polymer latex were investigated using confocal laser scanning microscopy. The latex was incorporated into the bitumen emulsion by using four different addition methods and all emulsions were processed with a conventional colloid mill. The emulsion binder films were studied after evaporation of the emulsion aqueous phase. We show how the microstructure and distribution of the polymer varies within the bitumen binder depending on latex addition method, and that the microstructure of the binder remains intact when exposed to elevated temperature. It was found that a distinctly fine dispersion of polymer results when the polymer is blended into the bitumen before the emulsifying process (a monophase emulsion). In contrast, bi-phase emulsion binders produced by either post-adding the latex to the bitumen emulsion, or by adding the latex into the emulsifier solution phase before processing, or by comilling the latex with the bitumen, water and emulsifier all resulted in a network formation of bitumen particles surrounded by a continuous polymer film. The use of emulsified binders appears to result in a more evenly distributed polymer network compared to the use of hot polymer-modified binders, and they therefore have greater potential for consistent binder cohesion strength, stone retention and therefore improved pavement performance.     

分散型固相萃取-气相色谱串联质谱法测定食品中8种芳氧苯氧丙酸酯类除草剂的残留量

建立了大豆、绿茶、大米、胡萝卜、菠菜、豌豆、大蒜、草莓、蜂蜜、猪肉、鱼肉、鸡蛋等12种食品中8种芳氧苯氧丙酸酯类除草剂残留量的分散型固相萃取-气相色谱串联质谱(DSPE-GC-MS/MS)分析方法。样品由含1%冰醋酸的正己烷的饱和乙腈溶液提取,分散型固相萃取法净化,采用气相色谱-串联质谱分时段反应离子监测技术进行测定,外标法定量。所有农药在10~1 000μg.L-1范围内线性良好;方法定量限(LOQ)均低于10μg.kg-1;在10、20、40μg.kg-1三个添加水平下,大豆等12种代表性基质中所有农药的平均回收率均处于70%~120%之间,RSD≤13%;该方法选择性较好,不仅能够用于多种食品基质的残留检测,而且还能较好地解决本底成分相当复杂的大蒜基质极易出现的干扰问题。     

树脂砂混砂机液料供给系统的改进

为提高混砂机液料供给系统的可靠性,进一步实现小型化、自动化,对采用气动控制方式的原有系统进行了改进,设计了新的液料阀,使液料供给能更方便地控制,对头、尾砂能更好地调节．同时彻底消除了操作人员误动作的可能性。     

Effect of treatment temperature on the microstructure of asphalt binders: insights on the development of dispersed domains

This paper offers important insights on the development of the microstructure in asphalt binders as a function of the treatment temperature. Different treatment temperatures are useful to understand how dispersed domains form when different driving energies for the mobility of molecular species are provided. Small and flat dispersed domains, with average diameter between 0.02 and 0.70 μm, were detected on the surface of two binders at room temperature, and these domains were observed to grow with an increase in treatment temperature (up to over 2 μm). Bee‐like structures started to appear after treatment at or above 100°C. Moreover, the effect of the binder thickness on its microstructure at room temperature and at higher treatment temperatures was investigated and is discussed in this paper. At room temperature, the average size of the dispersed domains increased as the binder thickness decreased. A hypothesis that conciliates current theories on the origin and development of dispersed domains is proposed. Small dispersed domains (average diameter around 0.02 μm) are present in the bulk of the binder, whereas larger domains and bee‐like structures develop on the surface, following heat treatment or mechanical disturbance that reduces the film thickness. Molecular mobility and association are the key factors in the development of binder microstructure.     

Development of a feedstock formulation based on polypropylene for micro-powder soft embossing process of 316L stainless steel micro-channel part

To exploit the potential of micro-system technology, the micro-powder embossing process, a rapid manufacturing production technology of microstructured die mould, was currently being investigated. Present work focused on establishing a suitable binder system for micro-powder embossing process. Multi-component binder systems, comprising of different weight percentages of paraffin wax, stearic acid and polypropylene were investigated. The compatibility between binder constituents was studied by thermogravimetric analysis (TGA) showing a partial miscibility between both components. The feedstock comprised of 316L stainless steel powder, and a wax-based thermoplastic binder was used to achieve a feedstock with 60 to 68 vol.% powder loading. The degradation temperature of binders was determined by using TGA and flow behaviour through rheometer. Homogeneity of the feedstock was verified by using TGA and scanning electron microscopy. Then, hot embossing was done, and it was found that the feedstock having solid loading up to 68 vol.% were successfully embossed, and components were without physical defects. The polymeric part was driven off by thermal debinding using a thermal cycle designed on the basis of a thermogravimetric study of the binder. Finally, the vacuum sintering of the parts allows high quality parts to be obtained.