酶联免疫法测定猪肉、猪肝和猪尿中盐酸克伦特罗

对4种国产及进口的酶联免疫法测试盒测定猪肉、猪肝及猪尿中克伦特罗残留量的性能及效果作了对比试验。试验时以上述3种样品为基体,加入1,2,3,5,10μg.kg-1(或μg.L-1)等5个浓度水平的克伦特罗标准溶液,然后用上述测试盒进行检测。从所得的结果可知,国内外的测试盒所得测定值间存在较大差异;猪尿样品的检测结果表明这些测试盒所采用的方法比较适合,但由猪肉及猪肝样品的检测结果可知,其中一些测试盒所采用的方法尚有改进的必要。     

一种适用于高分辨分子地层学研究的有机质分离及定量方法

研究全球变化的手段多种多样，高分辨分子地层学是最有力的工具之一，进行此项研究工作要分析的样品大且溶量小，因此建立一种合适的有机质分离及定量方法十分重要。本文采用冷抽提法的方法抽提出这类样品的有机质，衍生化合利用ＧＣ／ＭＳ对化合物进行定性、定量分析。利用本方法分析的空白加标（地质体中最常见化合物）回收率结果为：烷烃９５．８％，脂肪酸９２．３％，胆甾醇９９．７％；脂肪醇９３．７％；基质加标加收率结果为     

The Effects of Di- or Polysulfonates on Adsorption of Petroleum Sulfonates

Petroleum sulfonates was separated into several fractions with conventional extraction method according to the polarity of extraction solvent. The relative content of mono-, di-, or polysulfonates in each fraction was determined by using high pressure liquid chromatography and then the average sulfonic amount of each fraction can be calculated according to above results. The equivalent weight of each fraction was measured by both two-phase titration method and ESI-MS method, and the results shows the tow methods are comparatively coincident. Furthermore, the mean molecular weight of each fraction can be calculated with the average sulfonic amount and the equivalent weight. Adsorption isotherm and coreflooding adsorption test were both conducted to determine the adsorption amount and adsorption rate of each fraction. It was found that the fraction with the minimum equivalent weight is middle mean molecular weight and its adsorption amount on reservoir sand is maximal. Moreover, two fractions have a tendency to come to saturated adsorption in coreflooding adsorption test, but the time needed for saturated adsorption is distinctly different. However, the total adsorption amount of the other fractions keeps increasing at all time. The mechanisms accounting for the difference of adsorption performance were proposed on the basis of the diverse composition of the fraction.     

The Use of Corrected Thermal Decomposition Temperature in the Geological Interpretation. I

Dehydroxylation of kaolinite, thermal decomposition of calcite, dehydration of some cases of minerals bearing molecular water in the structure serve as example of the use of corrected temperature taking into the influencing quantity instead of the measured temperature. By using this, method data become more characteristic and comparable and the correction makes them suitable for further analysis, such as crystallinity, substitution, binding force, genesis etc. This revised version was published online in August 2006 with corrections to the Cover Date.     

复杂沉淀体系中沉淀剂合理用量的计算

在沉淀体系中,当有掩蔽剂存在时沉淀剂的合理用量及被沉淀离子在溶液中最小残留量的计算是个复杂问题。本文从理论上建立了解决这一问题的通用函数方程,并藉助于电子计算机进行实例处理,结果令人满意。     

Asymptotic finite‐time ruin probabilities for a class of path‐dependent heavy‐tailed claim amounts using Poisson spacings

In the compound Poisson risk model, several strong hypotheses may be found too restrictive to describe accurately the evolution of the reserves of an insurance company. This is especially true for a company that faces natural disaster risks like earthquake or flooding. For such risks, claim amounts are often inter‐dependent and they may also depend on the history of the natural phenomenon. The present paper is concerned with a situation of this kind, where each claim amount depends on the previous claim inter‐arrival time, or on past claim inter‐arrival times in a more complex way. Our main purpose is to evaluate, for large initial reserves, the asymptotic finite‐time ruin probabilities of the company when the claim sizes have a heavy‐tailed distribution. The approach is based more particularly on the analysis of spacings in a conditioned Poisson process. Copyright © 2010 John Wiley & Sons, Ltd.     

气相色谱法测定蔬菜中拟除虫菊酯类农药残留量

从1.0kg蔬菜中选其可食用部分,切碎后用四分法取样,取适量样品经充分捣碎制得分析用样品。称取试样25.00g用50mL乙腈高速匀浆提取,收集滤液40～50mL与5g氯化钠振荡盐析。定量分取上层清液10mL置于80℃水浴上吹氮至干,加正己烷2mL溶解残渣,所得溶液流经Florisil小柱纯化,用丙酮-正己烷(1+9)混合液淋洗2次,每次5mL,洗脱液在50℃水浴上吹氮至干,用正己烷定容至2.0mL,取1μL进样进行气相色谱分析。采用Varian CP-Sil 5CB毛细管色谱柱分离及电子捕获检测器定量检测,5种拟除虫菊酯类农药可很好地分离。其峰面积值与相应质量浓度均在0.01～1.0mg·L~(-1)之间呈线性,检出限(3S/N)在1.6～2.0μg·kg~(-1)之间。在3个浓度水平上(0.02,0.10,0.50mg·kg~(-1))加入各农药标准溶液,按方法作回收率及精密度试验,测得回收率和相对标准偏差(n=6)分别在90.5%～106.4%和0.98%～6.3%之间。     

凝胶渗透色谱-固相萃取净化-气相色谱-串联质谱法测定茶叶中33种农药的残留量

茶叶样品以乙酸乙酯-环己烷(1+1)混合溶液为提取剂高速匀浆提取,提取液经凝胶渗透色谱净化除去大部分的色素、脂类和蜡质,再用Carb-NH_2固相萃取小柱(SPE)进一步除去样液中残余的杂质。将洗脱蒸发至近干,加丙酮1mL溶解,采用气相色谱串联质谱法在分时段选择反应监测模式下进行测定,外标法定量。33种农药的测定下限(10S/N)均小于0.01mg·kg~(-1)。当加标水平为0.01mg·kg~(-1)时,大部分农药的回收率在75%～116%之间,相对标准偏差小于10%。     

Glass bead with minimized amount (11 mg) of sample for X‐ray fluorescence determination of archaeological ceramics

By using very small amount – 11‐mg – of sample powder, major oxides (Na₂O, MgO, Al₂O₃, SiO₂, P₂O₅, K₂O, CaO, TiO₂, MnO, and total Fe₂O₃) in ancient pottery (and igneous rocks) were determined with X‐ray fluorescence spectrometry. This minimized amount of sample was used to prepare a fused glass bead with 300 times the weight of lithium tetraborate as an alkali flux. Calibration standards were obtained by compounding chemical reagents (Na₂CO₃, MgO, Al₂O₃, SiO₂, Na₄P₂O₇, K₂CO₃, CaCO₃, TiO₂, MnO₂, and Fe₂O₃) and the flux. Fewer 11 mg of reagents as oxides were able to give reliable calibration curves with good linearity (correlation coefficient: r > 0.995). Fewer 11 mg of sample was able to give reliable analytical results with good precision (relative standard deviation: <3% for more than 10.0 mass% of analyte, <10% for 1.0–10.0 mass% of analyte, and <20% for 0.1–1.0 mass% of analyte). Lower limits of detection were roughly a sub‐percentage of analyte in an unprepared sample (e.g. 0.3 mass% for Na₂O, 0.5 mass% for MgO, 1.0 mass% for Al₂O₃, and 0.01 mass% for MnO). Composition of major oxides in artificial and natural aluminosilicate materials (including rock, stone, sand, sediment, and clay; and their products) should be fundamental information to be considered in detail. The present X‐ray determination based on very small amount of sample might be made readily accessible for destructive analysis of precious samples for archaeology (and geochemistry). Copyright © 2011 John Wiley & Sons, Ltd.     

Using mixture‐amount modeling to optimize the advertising media mix and quantify cross‐media synergy for specific target groups

One of the critical decisions in media planning is how to allocate advertising efforts across different media. While studies indicate that marketers can create positive synergy effects by spreading their effort across several media, there is little understanding of how much should be invested in each specific medium to optimize advertising results. In this study, we apply a novel methodology, mixture‐amount modeling, which allows advertisers to determine the optimal allocation of advertising effort across media as a function of the total advertising effort. Moreover, we test how the optimal allocation and the resulting response change for consumers with distinctive media usage patterns and varying degrees of product category experience. Based on these results, we quantify the potential synergy between media and calculate the synergistic capacity for specific target groups. We apply the model to data from 52 beauty care advertising campaigns that ran on TV and in magazines in the Netherlands and Belgium. We determine the optimal allocation of advertising investments (measured through Gross Rating Points) to maximize campaign recognition. Our findings support the existence of positive synergistic effects between magazine and TV advertising and illustrate that these effects depend on consumers' media usage and product category experience.