共查询到20条相似文献,搜索用时 78 毫秒
1.
2.
3.
建立高效液相色谱法测定土壤和淤泥中双酚A、壬基酚和辛基酚.样品采用超声波萃取,以体积比1∶1的正己烷和丙酮作为提取剂,体积比90∶10的乙腈和水作为流动相,经SupelcosilTM LC PAH色谱柱(250×4.6 mm,5 μm)分离后荧光检测器检测,双酚A、壬基酚和辛基酚的荧光激发波长是227 nm,发射波长为313 nm,样品在6 min中内完全出峰.该方法的线性范围在0.1~20 μg/mL之间,在0.1μg/mL、0.5μg/mL和1.0 μg/mL3个浓度的添加水平下土壤和淤泥样品的加入回收率分别在83.7%~115.6%之间和94.3%~106.2%之间.该方法简单、快速和经济,可用于淤泥和土壤实际样品检测. 相似文献
4.
塑料瓶中双酚A的电化学测定方法研究 总被引:1,自引:0,他引:1
制备了多壁碳纳米管修饰碳糊电极(MWCNTs/CPE),用循环伏安法(CV)和差分脉冲伏安法(DPV)研究了环境激素双酚A在多壁碳纳米管修饰电极上的电化学行为。结果表明,多壁碳纳米管修饰碳糊电极对双酚A有明显的电催化作用,在pH7.0的磷酸盐缓冲溶液(PBS)中,双酚A在0.504V处有1个明显的氧化峰。实验考察了底液的pH值、扫描速度、富集时间等因素的影响。在优化的条件下,双酚A的示差脉冲峰电流与其浓度在5.0×10^7-2.0×10^-5范围内呈良好的线性关系(r=0.99545),检出限为1.0×10^-7mol/L(S/N=3)。该法用于实际样品中双酚A含量的测定,回收率为104.4%,测定结果的相对标准偏差为3.9%(n=6)。 相似文献
5.
6.
综述了双酚A的直接电化学检测方法(用于裸电极表面的修饰材料包括纳米材料、新型材料和生物材料)和间接电化学检测方法(包括电化学适配体传感器,电化学酶传感器和电化学分子印迹传感器)的研究进展,并对其前景进行了简要展望(引用文献54篇). 相似文献
7.
双酚A的缩合及磺甲基化过程研究 总被引:1,自引:0,他引:1
磺化在有机合成中的一个重要作用是赋予主体化合物的水溶性。磺甲基化聚合物有很好的耐热稳定性,已广泛应用于油田、建材、医疗、制革等行业。本文通过对双酚A的磺甲基化反应过程中产物的分析研究,导出反应过程变化规律,研究清洁化制革用白色鞣剂的制备方法。 相似文献
8.
有机硅改性双酚A型环氧树脂研究 总被引:18,自引:0,他引:18
采用二氯二甲基硅烷 (DMS) ,或DMS与α ,ω 二氯聚二甲基硅氧烷 (DPS)的混合物来改性双酚A型环氧树脂 ,通过对固化物的冲击强度、拉伸强度、断裂伸长率和玻璃化转变温度 (Tg)的测定 ,探讨了改性方法、有机硅组成与含量等对材料性能的影响 .结果表明 ,用 5 7phr的DMS改性时 ,树脂固化物的冲击强度达2 0 2kJ m2 ,拉伸强度达 6 7 0MPa ,断裂伸长率达 11 2 9% ,Tg 达 16 8 0℃ ;分别比未改性时提高了 9 4kJ m2 ,2 1 1MPa ,5 4 %以及 32 6℃ .而用 0 7phrDMS +10phrDPS共同改性时 ,除Tg 和拉伸强度略有上升外 ,冲击强度达到了 31 6kJ m2 ,断裂伸长率达到 81 6 % ,分别比纯环氧提高了 2 0 8kJ m2 和 75 7% . 相似文献
9.
液相色谱-质谱法同时测定塑料制品中的双酚A和四溴双酚A 总被引:6,自引:0,他引:6
建立了高效液相色谱-质谱同时测定塑料制品中的双酚A(BPA)和四溴双酚A(TBBP-A)的方法。采用超声波萃取技术萃取样品。系统地考察了前处理条件、色谱条件和质谱参数。实验表明,在50 ℃条件下,加入20 mL二氯甲烷对塑料样品中的BPA和TBBP-A超声提取60 min可获得较好的提取效果。以甲醇和水为流动相,采用液相色谱-质谱联用分离和检测BPA和TBBP-A。该方法的线性范围为0.1~2.0 mg/L; BPA和TBBP-A检出限分别为0.01 mg/kg和0.02 mg/kg;回收率为85.4%~97.6%。该方法分离时间短,操作简便,实用性强,灵敏度高,适用于塑料制品中双酚A和四溴双酚A的残留分析。 相似文献
10.
11.
When bisphenol A polycarbonate is subjected to weathering conditions this polymer shows two different degradation mechanisms depending on the used irradiation wavelengths, i.e. photo-oxidation and photo-Fries rearrangement. The relative importance of these mechanisms in outdoor exposure conditions is still unknown. In this study bisphenol A polycarbonate is exposed to simulated weathering conditions. Different analysing techniques show that photo-oxidation is the most dominant degradation reaction. However, fluorescence spectroscopy shows that small amounts of photo-Fries rearrangement products are formed. With model compounds blended in polypropylene it is shown that the photo-Fries reaction increases the photo-oxidation rate, thus in PP the photo-Fries reaction can proceed through radical intermediates. However, this is not the case in PC, ageing at condition causing an increased photo-Fries reaction rate did not result in a higher oxidation rate. This implies that in PC the photo-Fries reaction does not initiate its oxidation and thus does not proceed through radicals. 相似文献
12.
Luigi Cobellis Nicola Colacurci Elisabetta Trabucco Carmen Carpentiero Lucia Grumetto 《Biomedical chromatography : BMC》2009,23(11):1186-1190
A sensitive HPLC method with fluorescence detection was developed for the determination of bisphenol A (BPA) and bisphenol B (BPB) in human blood serum. The detection limits of the method were 0.18 and 0.20 ng/mL for BPA and BPB, respectively. A single‐step liquid–liquid extraction was used for the pre‐treatment of serum samples. The recoveries of BPA and BPB spiked to sera were 85.6 and 87.7%, respectively. The analyses of sera from both healthy and endometriotic women emphasized the absence of bisphenols in all the control cases (11 women), whereas BPA was found in 30 sera (51.7%) and BPB was found in 16 sera (27.6%) in the group of 58 patients with endometriosis; in nine of such sera BPA and BPB were present simultaneously. Only relatively to the sera quantitated, BPA concentrations ranged from 0.79 to 7.12 ng/mL (mean concentration 2.91 ± 1.74 ng/mL), whereas BPB concentrations ranged from 0.88 to 11.94 ng/mL (mean concentration 5.15 ± 4.16 ng/mL). Therefore, the presence of at least one of the two bisphenols was verified in a percentage as high as 63.8% in the sera from endometriotic women, suggesting the existence of a relationship between endometriosis and BPA and/or BPB exposure. Indeed, it is well known that bisphenols can work as xenoestrogens, owing to their structural similarity to natural and synthetic estrogens (e.g. estradiol and dietilstilbestrol). However, further studies are necessary to confirm this hypothesis and to assess the actual dose at which exposures to bisphenols are able to increase the sensitivity of the endometriotic cells to estradiol. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
13.
《Green Chemistry Letters and Reviews》2013,6(1):81-86
Abstract Bisphenol A (BPA) is widely used as a color developer in thermal paper. Thermal paper is ubiquitous in daily life due to its use in cash register receipts, so opportunities for human contact abound. For this study, 10 blank cash register receipts were obtained from businesses in suburban Boston. BPA was extracted and analysis of concentration was performed using gas chromatograph/flame ionization detector. In some receipts, BPA was not detected but in others it was as high as 19 mg for a 12-inch long receipt, which is in line with concentrations indicated in patents. This study is intended to highlight the potential for human exposure to BPA as well as the ease with which exposure may be reduced through the use of BPA-free thermal paper. 相似文献
14.
2-Iodoxybenzoic acid (IBX) oxidation of bisphenol A (BPA) is described. The selective production of either the mono-o-quinone or the di-o-quinone can be controlled by IBX stoichiometry. Isolated yields of quinone were greater than 80%. Previous synthesis of BPA-di-o-quinone using a large excess of Fremy’s salt produced only trace amounts of product. In addition to o-quinone products, both mono- and dicatechols of BPA can synthesize in high yield and isolated without chromatography. The more stable catechols can be quantitatively converted back to o-quinones using silver oxide oxidation in either acetone or DMF. These one-pot reactions provide access to four different BPA metabolites in high yield and significant scale. 相似文献
15.
16.
When unstabilized bisphenol A polycarbonate is exposed to outdoor weathering conditions, it degrades due to irradiation, humidity and other parameters. To overcome this undesired degradation process BPA-PC can be stabilized. In this study the influence of different types of stabilizers (i.e. UV-absorbers and hindered amine stabilizers) on the photodegradation of BPA-PC were compared. It is shown that the best way to stabilize BPA-PC is to keep the harmful UV light out. Almost all stabilizers caused a decreased degradation rate. The UVAs showed the best results, although radical scavengers cause a decrease in degradation too. By applying a layer of UVA-stabilized BPA-PC on top of unstabilized BPA-PC led to a decreased degradation rate of the unstabilized BPA-PC, which can quantitatively be explained by a reduction of the irradiation intensity. 相似文献
17.
J. S. Grebowicz 《Journal of Thermal Analysis and Calorimetry》1996,46(3-4):1151-1166
Thermal properties of 4,4(2,2-propylidene)-diphenol, referred to as bisphenol A, or BPA, are discussed. Parameters of thermal transitions were measured by DSC. The commercial product crystallizes in -form crystals which melt at 157°C (onset) and 161°C (peak) with a heat of fusion 134.37 J g–1. Supercooled BPA shows a glass transition at about 40°C. Almost identical results were obtained for samples recovered by different methods: flakes, pastilles and prills. Two new polymorphs, the and -forms were identified. The -form melts at 131°C with a heat of fusion of 104.9 J g–1. The melting point of the -form was measured to be 138°C and its heat of fusion is 118.3 J g–1. Thermal conductivity of crystalline BPA was measured.Dedicated to Professor Bernhard Wunderlich on the occasion of his 65th birthdayThe author wishes to acknowledge helpful discussions with Dr. C. W. Uzelmeier and Dr. R. L. June during the course of this work. Many thanks go to J. M. Olvera for her help in gathering the experimental data. 相似文献
18.
研究发现在碱性介质中,纳米银对luminol-KMnO4化学发光体系的发光信号具有强烈的增敏作用,而双酚A对该体系具有明显的抑制作用,据此结合流动注射技术,建立了流动注射化学发光分析法测定塑料中双酚A的方法。该方法测定双酚A的线性范围为8.0×10-11~1.0×10-8g.mL-1(0.9926)和1.0×10-8~8.0×10-8g.mL-1(0.9916),检出限(3σ)为6.5×10-11g.mL-1。对5.0×10-10g.mL-1和5.0×10-8g.mL-1双酚A平行测定11次,其相对标准偏差为1.4%和1.0%。对反应机理进行了讨论。该方法简单、快速、灵敏度高,用于塑料制品中双酚A的测定,回收率为97.0%~105.0%。 相似文献
19.
Depolymerization of Poly(bisphenol A carbonate) in Subcritical and Supercritical Toluene 总被引:1,自引:0,他引:1
Zhi Yan PAN Zhen BAO Ying Xu CHEN 《中国化学快报》2006,17(4):545-548
The depolymerization of poly(bisphenol A carbonate)(PC) in subcritical and supercritical toluene was studied. The experimental parameters, which influence the depolymerization reaction such as temperature (570-633 K), pressure (4.0-7.0 MPa), reaction time (5-60 min), and toluene to PC weight ratio (3.0-11.0), were investigated, and the reaction products were determined by GC, GC/MS and FT-IR spectrometer. It was found that the main product of the depolymerization reaction was bisphenol A(BPA). BPA accounted for over 55.7% of the depolymerization products at reaction temperature 613 K, pressure 5.0-6.0 MPa, reaction time 15 min and toluene/PC weight ratio of around 7.0. 相似文献
20.
《Journal of separation science》2018,41(10):2269-2278
A method for the identification and quantification of bisphenol A and 12 bisphenol analogues in river water and sediment samples combining liquid–liquid extraction, precolumn derivatization, and ultra high‐performance liquid chromatography coupled with tandem mass spectrometry was developed and validated. Analytes were extracted from the river water sample using a liquid–liquid extraction method. Dansyl chloride was selected as a derivatization reagent. Derivatization reaction conditions affecting production of the dansyl derivatives were tested and optimized. All the derivatized target compounds were well separated and eluted in 10 min. Dansyl chloride labeled compounds were analyzed using a high‐resolution mass spectrometer with electrospray ionization in the positive mode, and the results were confirmed and quantified in the parallel reaction monitoring mode. The method validation results showed a satisfactory level of sensitivity. Linearity was assessed using matrix‐matched standard calibration, and good correlation coefficients were obtained. The limits of quantification for the analytes ranged from 0.005 to 0.02 ng/mL in river water and from 0.15 to 0.80 ng/g in sediment. Good reproducibility of the method in terms of intra‐ and interday precision was achieved, yielding relative standard deviations of less than 10.1 and 11.6%, respectively. Finally, this method was successfully applied to the analysis of real samples. 相似文献