无规共聚聚丙烯管材氧化诱导时间测试探究

以无规共聚聚丙烯（PP?R）管材为研究对象，采用差示扫描量热仪（DSC）测试了PP?R管材的氧化诱导时间（OIT），并研究了测试部位、样品直径、样品厚度以及取样方式等测试条件对OIT测试结果的影响。结果表明，从垂直管壁方向取芯层直径为6 mm、厚度为650 μm的试样进行测试时，OIT测试结果相对可靠。     

离子色谱法测定含银膏体中的氯离子含量

建立了有机溶剂萃取-氧弹燃烧-离子色谱法测试含银样品中的氯含量的分析方法。使用甲苯∶乙酸乙酯(1∶1)超声萃取含银样品30 min,萃取后的溶液经氧弹燃烧，采用离子色谱分析样品中的氯。结果表明，使用该方法的检出限为11 mg/kg;银浆样品中的加标平均回收率为80.2%;相对标准偏差(RSD)为11.3%。本方法与氧弹直接燃烧法相比，测得的氯含量大大提高，测试结果与快速自动燃烧炉-离子色谱法更接近，可以满足含银样品中氯的分析需要。此方法适合于样品含银时氯的分析。     

热电池负极材料锂硼合金结构研究及锂含量测定

分别采用XRD和SEM对锂硼合金进行了测试,结果显示锂硼合金为锂硼化合物和自由锂组成的双相结构。采用溶样、加热、过滤、清洗的新方法处理样品,取过滤清液酸碱中和滴定测试了样品中的总锂含量,并探讨了影响测试结果的几个主要因素。尝试在全程氩气保护下,采用DSC方法测试样品200℃附近的吸热数据,通过计算得到合金中自由锂含量。     

智能一体化蒸馏仪蒸馏-三氯甲烷萃取-4-氨基安替比林法测定土壤中挥发酚

采用30ml采样瓶采样，硫酸铜作保护剂，利用智能一体化蒸馏仪直接蒸馏，三氯甲烷萃取后分光光度法测试土壤中挥发酚检测灵敏度高，检出限为0.028mg/kg，实际样品加标回收率在94.7%-101.1%之间，实际土壤样品测试结果相对标准偏差RSD在0.4%-1.7%之间，方法准确可靠。     

热电池负极材料锂硼合金结构研究及锂含量测定

分别采用XRD和SEM对锂硼合金进行了测试,结果显示锂硼合金为锂硼化合物和自由锂组成的双相结构。采用溶样、加热、过滤、清洗的新方法处理样品,取过滤清液酸碱中和滴定测试了样品中的总锂含量,并探讨了影响测试结果的几个主要因素。尝试在全程氩气保护下,采用DSC方法测试样品200℃附近的吸热数据,通过计算得到合金中自由锂含量。     

傅立叶变换红外光谱法定量测定PVC玩具中的DEHP

采用傅立叶变换红外光谱法对PVC玩具中的DEHP含量进行了定量测定 ,该方法简单 ,结果可靠 ,适合于流水线的质量控制。又采用气相色谱法对同一样品进行测试 ,结果表明这两种方法的测试结果无显著性差异。     

高频炉燃烧红外吸收光谱法测定矿渣硅酸盐水泥中的三氧化硫

本文建立了用高频炉燃烧红外吸收光谱仪测定矿渣硅酸盐水泥中三氧化硫含量的方法，采用化学方法前处理样品，消除硫化物的干扰，选用复合助熔剂，并优化了最佳仪器测试条件，检测结果准确可靠，15 min即可完成三氧化硫的检测。     

化妆品微生物检验菌落总数不确定度评定

为减少实验计算误差,对某一化妆品微生物菌落总数进行不确定度的评定。对同一样品由同一操作人员采用同一方法重复测试10次,用两种不同的评定方法,分别取平均值以及对数平均值作为测试结果。结果确定该样品菌落总数的置信区间范围为5.8×103≤x≤1.1×104。表明菌落总数检测结果分散性较大时宜采用对数平均值作为测试结果进行评定。     

高频感应燃烧-红外吸收法测定石墨烯中总硫含量

建立了一种低样品用量的高频感应燃烧-红外吸收测定石墨烯中总硫含量的方法。分别考察了助熔剂的种类、用量、叠放顺序，建立工作曲线所用标准物质等因素对测量结果的影响。结果显示对石墨烯样品进行简单的压缩后，使用0.6g铁屑和0.8g钨锡助熔剂，采用铁屑在下、样品中间、助熔剂在上的叠放顺序，使用低合金钢标准物质建立工作曲线，仅需要0.015g石墨烯样品即可以得到稳定可靠的测试结果。方法的检出限为0.0033%，定量限为0.011%，可用于石墨烯中低含量硫的准确测定。使用最优条件测定市售7个厂家共11个石墨烯样品的总硫含量，测定结果为0.082%～3.60%，与仲裁方法艾士卡法的偏差为-0.07%～0.06%，两种方法没有显著差异。测定结果的相对标准偏差为0.73%～1.97%，精密度优于艾士卡法。同时测试结果也表明，市售石墨烯样品中硫元素含量大多不能忽略不计，在石墨烯的应用过程中需引起足够重视。     

地下水中α、β放射性检测时间优化研究

按照国家标准方法将不同浓度α、β标准源样品（水样）、地下水进行前处理，将经过前处理的水样残渣样品上机进行测试，以测试时间为自变量，得到在不同测试时间下测得的水样中α、β的放射活度。将测定结果以F检验法检验是否存在明显差异，根据检验结果得到在方法可接受范围内最优的上机测试时间。     

城市给水厂应对原水发生邻苯二甲酸酯污染的处理技术及处理效能

城市水源水邻苯二甲酸酯(PAEs)污染对饮用水水质安全产生了威胁。综述了国内地表水(包括城市水源水)和给水厂处理出水中PAEs的污染情况,提出粉末炭(PAC)吸附与混凝沉淀联用技术(以下简称联用技术)是适合国内目前大多数水厂实情的可以有效应对水源水发生PAEs污染的水处理技术。开展了联用技术对原水中邻苯二甲酸二(2-乙基己基)酯(DEHP)的去除效能的实验研究。结果表明,联用技术可以有效地去除原水中DEHP,处理出水浊度是影响DEHP去除效果的重要因素,PAC理化特征对联用技术去除原水中DE-HP效果的影响不大。最后基于小试实验结果给出了不同污染水平下联用技术中PAC的建议投量,为实际生产提供了技术参考。     

可见光催化降解水中邻苯二甲酸二异辛酯的研究

邻苯二甲酸二异辛酯(DEHP)是环境激素类物质的一种,在环境中该物质持久存在不易分解,对人体健康造成严重危害,因此研究其废水降解具有重要的意义。以氙灯作为可见光光源,纳米CuPcTs/TiO2为催化剂,在可见光照射下较系统地考察了催化剂的活性、初始溶液的pH值、催化剂用量、光照时间等因素,对水溶液中DEHP光催化降解进行了研究。结果表明在pH=5,催化剂用量为0.4 g/L,光照时间为50 min,初始浓度为10 mg/L的DEHP水溶液降解速率为最佳,降解率达到93.6%,并证明了只有在催化剂和光源协同作用时,水中DEHP才可获得较快的降解。     

手机涂料及涂膜中邻苯二甲酸酯类有害物质的测定

涂料经溶剂提取或涂膜经索氏提取后,提出液中邻苯二甲酸酯类单体DEHP、DBP、BBP、DNOP可用DB-130.0m×φ0.25mm×0.5μm色谱柱同时分离,GC-FID或GC-MSD全扫描测定,DINP、DIDP宜采用GC-MSD选择离子扫描单独测定。采用GC-MSD测定时,方法的回收率不低于95%,DEHP、DBP、BBP、DNOP的最小检出限(LODs)均为0.04μg/mL,最低定量限(LOQ)均为0.35μg/mL。选择扫描时,DINP、DIDP的LODs、LOQ分别为0.4μg/mL、3.5μg/mL。实验结果表明:某些丙烯酸树脂涂料以及手机外壳涂层含有高含量生殖致癌物PAEs类单体,应为制定手机涂料中邻苯二甲酸酯类有害物质最高允许限量进行评价。     

化妆品包装材料中邻苯二甲酸双(2-乙基己基)酯迁移量的测定

建立了化妆品包装材料中邻苯二甲酸双(2-乙基己基)酯迁移量(DEHP)的气相色谱质谱检测方法。化妆品包装材料样品采用不同模拟物在不同条件下浸泡后,浸泡液经正己烷萃取,气相色谱质谱联用仪分析,外标法定量。在优化的条件下,DEHP在0.01~10.0 mg/L浓度范围内线性关系良好,相关系数为0.999 3,方法检出限为0.10 mg/L。在空白样品中添加低、中、高3个浓度水平时,平均加标回收率在90%~110%之间,相对标准偏差在2.4%~8.2%之间。方法简单快速、灵敏可靠,可满足化妆品包装材料中DEHP迁移量的检测需求。对阳性样品中DEHP的迁移行为进行研究,结果表明DEHP迁移量随着浸泡液中乙醇比例的增大和浸泡时间的增加而增加。     

Nonisothermal crystallization kinetics of poly(vinylidene fluoride) in a poly(vinylidene fluoride)/dibutyl phthalate/di(2‐ethylhexyl)phthalate system via thermally induced phase separation

The nonisothermal crystallization kinetics of poly(vinylidene fluoride) (PVDF) in PVDF/dibutyl phthalate (DBP)/di(2‐ethylhexyl)phthalate (DEHP) blends via thermally induced phase separation were investigated through differential scanning calorimetry measurements. The Ozawa approach failed to describe the crystallization behavior of PVDF in PVDF/DBP/DEHP blends, whereas the modified Avrami equation successfully described the nonisothermal crystallization process of PVDF. Two stages of crystallization were observed in this analysis, including primary crystallization and secondary crystallization. The influence of the cooling rate and DBP ratio in the diluent mixture on the crystallization mechanism and crystal structure was determined by this method. The Mo approach well explained the kinetics of primary crystallization. An analysis of these two methods indicated that the increase in the DBP ratio in the diluent mixture caused a decrease in the crystallization rate at the primary crystallization stage. The activation energy was determined according to the Kissinger method and also decreased with the DBP ratio in the diluent mixture increasing. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Surface molecularly imprinted polymers based ZnO quantum dots as fluorescence sensors for detection of diethylhexyl phthalate with high sensitivity and selectivity

This work describes the preparation of molecularly imprinted polymers using ZnO quantum dots, which were used for the selective detection of diethylhexyl phthalate (DEHP). Methacrylic acid, ethylene glycol dimethacrylate, 2,2′‐azobis(2‐methylpropionitrile) and ZnO were used as functional monomer, crosslinker, initiator and optical material, respectively. Molecularly imprinted polymers were successfully synthesized, and the linear relationship between fluorescence intensity and amount was from 0.5 to 40 µmol L^?1 for DEHP. The coefficient of correlation was 0.9923 and the imprinting factor was 11.16. The results were above 97.50% and relative standard deviation below 3.86% for the detection of DEPH in actual water samples. This study could provide a novel method using molecularly imprinted polymers for highly selective and sensitive detection of DEHP. © 2018 Society of Chemical Industry     

SPE-GC/MS法快速检测水体中多组分内分泌干扰物

采用固相萃取-气相色谱/质谱法(SPE-GC/MS)研究了温州8个水体中邻苯二甲酸二甲酯、西玛津、莠去津、甲草胺、邻苯二甲酸二丁酯、双酚A、邻苯二甲酸二(2-乙基己基)酯七种内分泌干扰物的残留。水样用C18柱固相萃取进行富集、3mL10%的甲醇水溶液淋洗、10mL丙酮洗脱;并采用GC-MS法对七种内分泌干扰素进行分析。本实验建立的方法定性定量准确、可靠,适用于水体中多组分内分泌干扰物的快速检测,在所有测定的水样中,邻苯二甲酸二丁酯、双酚A、邻苯二甲酸二(2-乙基己基)酯是主要残留物,最高残留邻苯二甲酸二丁酯、双酚A、邻苯二甲酸二(2-乙基己基)酯分别为0.82、3.16、1.50ng/L。     

PVC制品中增塑剂DEHP含量的测定

建立了荧光光度法间接测定聚氯乙烯(PVC)制品中邻苯二甲酸二(2-乙基己酯)(DEHP)含量的方法。PVC制品中的DEHP经超声提取后,碱性水解生成邻苯二甲酸钠,将其置于pH值为7.6的磷酸盐缓冲溶液中,同Fenton反应产生的羟基自由基(?OH)反应,生成具有荧光的羟基邻苯二甲酸钠,测定其荧光强度可求出DEHP的含量。DEHP浓度在4.28×10-2～2.14mg/ml范围内与荧光强度呈线性关系,相关系数为0.9954。本测定方法操作简便,具有较高的灵敏度和准确度。     

Effect of dietary di-2-ethylhexyl phthalate on oxidation of14C-palmitoyl CoA by mitochondria from mammalian heart and liver

Oxidation of [1-¹⁴C] palmitoyl CoA by heart and liver mitochondria from rats fed dietary di-2-ethylhexyl phthalate (DEHP) was investigated in vitro. Oxidation of¹⁴C-palmitoyl CoA to¹⁴CO₂ increased two- to threefold in hepatic mitochondria from rats fed 0.1% DEHP for 2 to 3 days; this increase appeared to be a maximum response since similar data were obtained using hepatic mitochondria from rats receiving 0.5% or 1.0% DEHP in the diet. The response of hepatic mitochondria to DEHP was found to continue throughout the duration of 35-day trials in which 1.0% DEHP was fed. In contrast to hepatic mitochondria, the oxidation of¹⁴C-palmitoyl CoA by heart mitochondria decreased ca. 40% upon addition of 0.1% or 0.5% DEHP to the diet; this effect of DEHP on heart mitochondria was not sustained beyond ca. 8 days of DEHP feeding. Limited studies were also performed in rabbits and pigs. Oxidation of¹⁴C-palmitoyl CoA was increased ca. twofold in hepatic mitochondria from rabbits fed 1% dietary DEHP for 12 days and in hepatic mitochondria from pigs that received 5 doses of DEHP (0.8g/kg) at 12-hr intervals; the oxidation¹⁴C-palmitoyl CoA by heart mitochondria from these same animals was unchanged in the rabbit but increased an average of 37% in the pig. DEHP feeding to rats was associated with increased yields of hepatic mitochondrial protein; standardized preparations of heart mitochondria were not similarly affected.     

The effect of feeding di-(2-ethylhexyl) phthalate (DEHP) on the lipid metabolism of laying hens

Di-(2-ethylhexyl)phthalate (DEHP), a commonly used plasticizer, is now seen as an environmental pollutant. DEHP has been found to inhibit lipid and sterol synthesis in rats and mice. The effects of DEHP on various aspects of lipid metabolism were examined in chickens. White Leghorn laying hens were fed either a standard laying mash control diet (C) or the control diet containing 1% DEHP (DEHP) or 1% DEHP and 5% tallow (DEHP-T) for 28 days. DEHP and DEHP-T lowered feed consumption 10% but did not significantly affect body weight. After 3 weeks on the diets, egg production was 15–20% less in DEHP-T than in C and DEHP hens. No differences were observed in egg weight, percent shell, white or yolk among the groups. DEHP and DEHP-T did not alter egg lipid or egg cholesterol concentrations. DEHP and DEHP-T lowered plasma lipid concentration about 20% and free and total cholesterol 20–30%. Liver weights increased, being 30, 34 and 39 g for C, DEHP and DEHP-T hens, respectively, after 28 days. Total liver lipid and cholesterol increased 19% and 26% in DEHP hens and 54% and 79% in DEHP-T hens when compared to controls. In contrast, the fat content of pectoralis major muscle decreased significantly in DEHP and DEHP-T hens. These results, in showing that DEHP alters plasma and tissue cholesterol but not yolk cholesterol, demonstrate again that egg cholesterol is remarkably resistant to alteration by dietary means.