原子荧光在食品、化妆品中汞含量检测的应用

采用微波消解-氢化物发生-原子荧光光谱法对七种食品和三种化妆品中Hg含量进行测定,讨论并确定了样品的预处理方法和还原剂浓度。结果表明,食品和化妆品中Hg的检出限为0.0100μg/L和0.0070μg/L,回收率为88.93%~107.75%,相对偏差为≤5.75%。该方法准确、灵敏、简便、快速,是测定食品和化妆品中Hg含量的理想方法。     

超级微波消解-电感耦合等离子体质谱法测定彩妆类化妆品中铅、砷、汞、镉、铬的含量

通过对样品前处理和电感耦合等离子体质谱法（ICP-MS）仪器参数进行优化，采用铼（Re）、铑（Rh）作为内标元素，建立了超级微波消解-ICP-MS同时测定彩妆类化妆品中铅（Pb）、砷（As）、汞（Hg）、镉（Cd）、铬（Cr）5种重金属元素。结果显示，5种重金属元素在一定浓度范围内，线性关系良好，线性方程相关系数均大于0.998，低、中、高浓度加标回收率范围为93.8%～104.1%，相对标准偏差（RSD）为0.84%～6.11%(n=6)，检出限为0.001 7～0.011μg/L，检出浓度为0.21～1.4μg/kg。该方法专属性强、灵敏度高，可快速、准确测定彩妆类化妆品中5种重金属元素。     

睡莲花、破布木果等五种药材重金属含量分析

以《中国药典》2015版为评价标准,采用微波消解-原子吸收光谱法-原子荧光光谱法对睡莲花、破布木果、大黄、山奈、卡西甫枣中镉(Cd)、铅(Pb)、铜(Cu)、汞(Hg)及砷(As)5种重金属或类金属元素含量进行测定。结果表明,样品中五种重金属元素含量均符合《中国药典》2015版规定,各元素在实验范围内线性关系良好,相关系数大于0.999;精密度试验RSD(n=6)为0.68到1.64之间,加标回收率在99.88%到105.0%之间。方法操作简便,适用于中药材中微量重金属元素的检测。     

ICP-OES法同时测定化妆品中砷、铅和镉

建立微波消解-电感耦合等离子体发射光谱(ICP-OES)法同时测定化妆品中砷(As)、铅(Pb)和镉(Cd)。方法采用硝酸-双氧水体系,优化了ICP-OES条件。结果表明,3种重金属元素在0.05~1.20 mg/L范围内呈良好线性关系;As,Pb和Cd的相关系数均为0.999 8,检出限分别为0.63,0.30和0.015 mg/kg,定量限分别为2.1,1.0和0.05 mg/kg,平均加标回收率为90.7%~108.6%,相对标准偏差为0.44%~4.59%(n=6)。     

ICP-MS法检测3种铜型微量元素中砷、铅、镉和汞的含量

研究了ICP-MS测定铜型微量元素中As、Pb、Cd和Hg 4种有毒重金属元素的方法。以Ge、In和Bi为内标,补偿基体效应,采用ICP-MS同时测定上述4种元素。待测元素浓度在0~100μg/L范围内,相关系数在0.999 9以上,检出限为0.010~0.021 ng/L,加标回收率在98.3%~108.2%之间,精密度良好RSD<6.3%。本研究所建立的方法具有简便、快速、准确、灵敏度高的优点。     

阿胶中砷、镉的测定

研究了氢化物发生一原子荧光光谱法测定阿胶中砷、镉的方法,对仪器的工作条件及试验条件进行优化。在选定的最佳测定条件下,本方法检出限低至As 0.0257μg/L、Cd 0.00421μg/L;回收率As为95.30%、Cd为97.00%。精密度为As 0.4%、Cd2.72%。测定阿胶中的砷和镉元素,结果令人满意。     

氢化物发生MP-AES法测定印刷品中的可迁移元素

研究应用氢化物发生-微波等离子体原子发射光谱法同时测定印刷品中的砷（As）、钡（Ba）、汞（Hg）、镉（Cd）、铬（Cr）、铅（Pb）、锑（Sb）、硒（Se）8种有害可迁移元素。文中对比了多模式进样氢化物发生法与单通道进样模式的方法检出限,并进行了重复性、加标回收率实验。方法检出限对比实验结果表明,多模式进样氢化物发生法的方法检出限范围为0.000 7~0.019 8μg/mL,优于仪器检出限范围0.000 2~0.230 8μg/mL;重复性实验结果表明,各元素检测相对标准偏差小于1.8%;加标回收率范围为92.0%~120.0%。综上所述,该方法具有较好的精密度和准确性,适合印刷品中有害可迁移元素的分析。     

氢化物原子荧光法测定化妆品中的砷

采用微波消解技术对样品进行消解,用氢化物原子荧光法测定样品。结果表明,在0~20μg/L范围内,砷含量与原子荧光强度呈良好的线性关系,相关系数为0.9997,方法检出限为0.0088μg/L,样品加标回收率在95%~105%。     

原子荧光光谱法同时测定农产品产地土壤中砷、汞

农产品产地土壤经王水水浴直接消解,硫脲和抗坏血酸作为还原剂,采用氢化物发生原子荧光光谱法双道同时测定砷、汞元素。结果表明,砷、汞元素校正曲线相关系数分别为0.9997和0.9999。方法检出限砷0.010μg/g,汞0.002μg/g。加标回收率砷为97.7%~101.4%,汞为97.3%~99.2%。     

微波消解ICP-MS法测定5种中药材中重金属元素的含量

目的测定丹参、金银花、天麻、薄荷、蒲公英五种中药材中重金属的含量,对重金属元素污染情况进行考察和研究。方法样品经微波消解后,采用电感耦合等离子质谱法(ICP-MS)直接对5种中药材试液中Pb、As、Cu、Cr、Cd的含量进行测定。结果各元素线性关系良好(r≥0.9996),Pb、As和Cd的质量浓度在0.1～100μg·L-1范围内呈良好线性关系,检出限分别为0.025、0.026、0.048μg·L-1,Cu、Cr的质量浓度在10～100μg·L-1范围内呈良好线性关系,检出限分别为2.5、2.4μg·L-1。以丹参样品作加标回收试验,回收率在99.0%～108.5%之间。结论方法准确、灵敏度高、可为中药材中重金属及有害元素的检测、质量控制提供方法参考。     

乙烯酮(双乙烯酮)下游产品废水的治理技术

乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。     

几种乙炔加压设备性能的比较

阐述并比较了几种加压设备在乙炔加压清净过程中的性能和特点。     

三种煤样燃烧热的测定

本文通过三个厂家提供的三种煤样燃烧热的测定,由测定结果综合得出3号煤样燃烧最完全、燃烧热也最大,是三个煤样中最好的一种。     

Semi-empirical equation of state of metals. Equation of state of aluminum

A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO₂) of density 0.08 g/cm³. __________ Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008.     

小议汽车涂装工艺设计对涂装成本的影响

论述了涂装工艺设计对涂装设备投资、涂装生产成本的影响。     

水泥水化热测定方法综述

水泥水化热是中、低热水泥和核电工程用水泥的一项关键的技术指标。全球范围内测定水泥水化热的方法有溶解法、直接法/半绝热法、等温传导量热法三种。本文总结了中、美、欧相关方法标准,对其测试原理、仪器设备、试验过程等方面进行了比对,并对其在领域的应用做了简单的概括。     

Measurement of the gradient of viscosity with composition of mixtures of non-ideal gases

A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%.     

塔设备改造选型的分析

就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后，着重介绍一种新型塔板（导向梯形浮阀塔板）和一种新型填料（波环填料——乾隆帕克）。     

Calorimetric and Computational Study of Enthalpy of Formation of Diperoxide of Cyclohexanone

A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out.     

Effect of degree of deacetylation of chitin on the properties of chitin crystallites

In the present article, chitin from crab shell was systematically deacetylated using a NaOH treatment with control of the reaction time. The degree of deacetylation, monitored using solid-state NMR, revealed that the reaction was pseudo-first order. Based on this, swollen and NaOH-saturated particles are proposed as the reaction system. The weight loss of the partially saponified and neutralized samples after HCl hydrolysis increased linearly with the degree of deacetylation. The crystallinity of the samples was found to increase after acid hydrolysis. According to conductimetric titration, the surface charge density of the crystallites, after acid hydrolysis, was found to increase with base treatment time. The effect of surface charge on the formation of a chiral nematic phase, due to the rodlike nature of the crystallites, was explored. These results show that because the contribution of charged particles to the ionic strength was significant the double layer compression was affected, especially since the surface charge density was close to the Manning limit. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:373–380, 1997