液相-电喷雾质谱法测定PVC玩具中邻苯二甲酸酯类增塑剂

本文采用液相-电喷雾质谱(HPLC-ESIMS)法对聚氯乙烯玩具中的六种邻苯二甲酸酯类增塑剂 (DEHP、DNOP、BBP、DBP、DINP和 DIDP)进行了测定.样品用21的氯仿-甲醇溶液在索氏提取器中浸提, 以乙晴-水为流动相进行梯度淋洗分离, 检测波长为224nm, DEHP、DNOP、BBP、DBP的检出限大约为5×10-6, DINP和DIDP因是其同分异构体的混合物, 峰比较宽, 灵敏度不高, 检出限大约为5×10-5. 本方法适用于PVC儿童用品和玩具中DEHP、DNOP、BBP、DBP、DINP和DIDP等邻苯二甲酸酯增塑剂的测定.     

浅谈接装纸印刷加工工艺

接装纸是一种卷烟用包装材料,用作滤嘴的外包装,属特种工业用纸.近年来,接装纸在功能和用途上有了很大的发展和创新,烟厂对接装纸的用途不仅仅局限于单纯的包装,更注重装饰性,对接装纸的印刷美观性有了更高要求.同时,随着卷烟健康环保的呼声日益高涨,国家及卷烟厂对接装纸的健康环保性以及其在卷烟降焦工程中的作用也提出了更高的要求.这些部使得接装纸的各方面性能要求不断提高,生产加工工艺也不断改进.     

GPC-GC-MS/MS同时测定含油食品中16种邻苯二甲酸酯

研究建立了含油食品中16种邻苯二甲酸酯含量的凝胶渗透色谱-气相色谱-串联质谱(GPC-GC-MS/MS)测定方法。含油食品经过提取后,提取液经凝胶渗透色谱分离纯化后进GC-MS/MS检测。系统优化了样品前处理方法,净化液在GC-MS/MS多反应检测(MRM)模式下进行检测,采用外标法定量分析。结果表明:该方法在0～16 mg·kg~(-1)范围内具有良好的线性关系,相关系数R~2在0.998 64～0.999 22。含油脂样品中16种邻苯二甲酸酯的加标回收率为84.85%～107.45%;方法检出限为100～200μg·kg~(-1),相对标准偏差(n=6)在2.0%～5.0%。本方法准确、稳定、简便、重复性较好,可应用于含油脂食品中16种邻苯二甲酸酯的实际检测分析。     

食品包材中五种邻苯二甲酸酯的检测

以市售的食品纸质包材作为研究对象,对其中DMP、DEP、DBP、BBP和DNOP等5种邻苯二甲酸酯类进行测定。建立超声-微波协同萃取与DAD检测,采用单因素试验和正交试验确定提取条件:以甲醇为提取剂,在225 W功率、料液比1∶110条件下萃取8 min;采用等梯度洗脱,确定洗脱条件:选用XBP C18液相色谱柱,检测波长为224 nm,柱温30℃,甲醇∶水(75∶25)为流动相,流速1.0 mL/min,进样量10μL。结果表明,该方法准确可靠,精密度相对标准偏差RSD为1.80%~2.80%,回收率为86.25%~92.50%,符合常规检测要求,可用于纸塑包装材料中邻苯二甲酸酯的检测。     

SPME-GC法测定塑料玩具制品在模拟汗液浸泡液中的DEHP

利用新型溶胶-凝胶富勒烯涂层,结合顶空固相微萃取-气相色谱法,对PVC玩具制品在模拟汗液浸泡液中增塑剂邻苯二甲酸二(乙基己基)酯(DEHP)进行了分析和测定,测量溶液中最低检出限为1.56ng/L,实际样品的可测最低含量为0.001%.RSD=3.57(n=7).并对模拟汗液中DEHP的萃取、分析进行了条件优化.     

超声萃取-高效液相色谱法测定水性涂料中烷基酚聚氧乙烯醚含量

以甲醇为萃取剂,建立了超声萃取-高效液相色谱法(HPLC)测定水性涂料中烷基酚聚氧乙烯醚含量的方法.样品经甲醇超声提取,过0.22 μm有机相滤膜,采用高效液相色谱仪(紫外检测器277 nm)测定.结果表明,辛基酚聚氧乙烯醚(OP10EO)和壬基酚聚氧乙烯醚(NP10EO)在线性范围1～50 μg/mL具有良好的线性关...     

水产品中结晶紫检测污染原因分析及应对措施

本研究应用高效液相色谱串联质谱法（HPLC/MS/MS）测定了样品抽取、传递和实验室检测过程中常用的笔、纸、标签、样品袋中结晶紫（含隐性结晶紫）的含量。纸试样采用乙腈直接提取,笔试样采用书写划痕后再用乙腈提取,HPLC/MS/MS定量测定。结果表明,除样品袋、滤纸、实验室无色标签纸和签字笔中不含有结晶紫（含隐性结晶紫）外,其余供试物品均含有一定量的结晶紫（含隐性结晶紫）,其中A4打印纸、标签纸和圆珠笔中含量很高。为降低取样和检验过程中的污染风险,本文还对生产和检验检测各环节需要注意的问题做了较为详细的分析。本研究结果将有利于建立有效预防体系,从而最大程度避免样品在生产、检验和检测过程中的本底污染和假阳性结果。     

安捷伦推出食品原物料与成品中13种增塑剂（Phthalate）快速检测方法

安捷伦最近推出利用超高灵敏的分析工具一快速液相串联质谱仪进行微量分析方法。快速液相色谱串联质谱仪可以减少系统背景干扰与溶剂使用量,同时搭配简单萃取与稀释的样品前处理方法,可以同时分析13种邻苯二甲酸酯类：DMP、DEP、DAP、DPP、DBP、BBP、DCP（Dicyclohexy!phthalate）、DNHP、DEHP、DEHA、DNOP、DINP和DIDP。本方法快捷、准确是解决大批量样品,高通量分析的最佳方法。     

气相色谱-质谱法分析玩具PVC塑料中的邻苯二甲酸酯增塑剂

[目的]研究开发针对PVC玩具中包括欧盟指令1999/815/EC禁用的DBP、BBP、DEHP、DNOP、DINP、DIDP在内的8种增塑剂的GC/MS测定方法.[方法]采用二氯甲烷做萃取剂,用溶剂抽提仪在两个小时内实现快速增塑剂提取,采用总离子流色谱(TIC)和选择离子色谱(SIM)测定增塑剂含量.[结果]解决了含多种同分异构体的DINP、DIDP与DNOP之间色谱峰重叠的问题,具有较好的线性关系及回收率.[结论]可满足欧盟法规的检测限要求.     

市售油性记号笔对水产品中结晶紫检测污染研究

本文研究用超高效液色谱串联质谱法(UPLC/MS/MS)测定市售4种常见品牌的黑色、蓝色、红色油性记号笔中结晶紫(含隐性结晶紫)的含量。待测笔样直接在称量纸上书写若干直线,再用乙腈提取,UPLC/MS/MS测定,内标法定量。结果表明,4种品牌的黑色、蓝色油性笔均检出结晶紫(含隐性结晶紫),而红色油性笔中结晶紫(含隐性结晶紫)含量较低或未检出。水产品检测过程中样品应避免直接接触到油性记号笔的染料,以防止样品在检测过程中的本底污染和假阳性。     

White Paper,Blue Print

The Chinese government raises high focus on energy problem by its first ever issued white paper on China＇s energy conditions and policies.Titled ＂China＇s Energy Situation and Policy＂,the 16,000-word whitepaper published on December 26 last year by China＇s Information Office of the State Council,under the joint compilation of the Energy Bureau and the Institute of Macro Economics and the National Development and Reform Commission （NDRC）,discusses the current energy situation in all-round way.     

阳离子交换高效液相色谱法测定纸巾纸和卫生纸中的丙烯酰胺单体残留量

建立了阳离子交换高效液相色谱法测定纸巾纸和卫生纸中的丙烯酰胺单体残留量的检测方法,方法的检出限为1mg/kg,回收率为90.4%-104.2%,相对标准偏差为2.3%,线性相关系数为0.9998,该方法简单、易操作、灵敏度高,是测定纸巾纸和卫生纸中丙烯酰胺的有效测定方法。     

近红外光谱法快速测定纸浆水分

本文主要介绍了近红外光谱法快速测定纸浆水分,它较传统方法更为简单、快捷、高效,在使用过程中具有优越性,可以进行推广使用。     

低档卷烟短缺的经济学分析

保持低档卷烟的适度供求平衡是目前烟草行业的一个重大课题.现有的分析主要把低档卷烟短缺的原因归结为消费税提高、原辅料涨价等产业外部因素.本文试图从产业内部的角度,通过厂商行为的理论和实证分析,揭示造成短缺的四种内部因素.在此基础上,对缓解短缺的方法进行评析并提出最优的解决办法.     

我国造纸业国际竞争力的实证分析与发展对策

本文通过测算1997—2002年的市场占有率、RCA指数、TC指数和MI指数,对我国造纸业的国际竞争力进行了评估和实证分析,得出了我国造纸业出口缺乏竞争力的结论。在分析我国造纸业发展现状和存在问题的基础上,提出了提升我国造纸业国际竞争力的对策与思路。     

世界纸和纸板产业内贸易及其影响因素分析

本文用产业内贸易理论来分析影响世界纸和纸板的贸易格局的因素。论文首先分析了世界纸和纸板的贸易状况;然后对世界纸和纸板的产业内贸易水平进行了测算,得出结论:世界绝大部分纸和纸板以产业内贸易方式参与国际贸易;最后对影响纸和纸板产业内贸易的因素进行了实证分析。     

The Advertising–price Relationship: Theory and Evidence

The relationship between advertising and price is important because the welfare effect of advertising depends upon the price effect of advertising. We attempt to provide a better understanding of the theoretical relationship between advertising and price. We establish theoretical conditions sufficient for advertising to raise prices. This will occur, for example, when firms play a supermodular game – a structure that considers the type of advertising (i.e., persuasive, image creating, or informative) and the effect that advertising has on a firm’s demand and costs. We also compare results from two simple duopoly models, one with horizontal and the other with vertical differentiation, and find that only the model with horizontal differentiation is supermodular for the forms of advertising that are thought to raise price (e.g., persuasive advertising). In consideration of these theoretical issues, we then develop an empirical model to determine whether advertising raises prices in the US brewing and cigarette industries.     

Uncovering emotions and insights evoked by paper currency

Despite the pervasiveness of paper currency in market exchanges, consumer research has focused only on its effects based on denomination and physical appearance. Previous work noted that the physical appearance of paper currency elicits emotions such as disgust and pride. However, no other research to date has uncovered additional emotions elicited by bills. The purpose of this study is twofold: (1) to uncover the series of emotions elicited by paper currency and (2) to expose additional insights. Consumer narratives were collected using the critical incident technique. Both elicited emotions and insights were identified and classified according to existing classifications of emotions and money insights in the literature. Our study revealed a unique set of emotions and insights not previously classified in prior research. Implications for practice and directions for future work are noted.     

Product Quality,Cost Asymmetry and the Welfare Loss of Oligopoly

When competition is tough, firms which do not implement the least expensive technology are forced to exit, or the low cost firms are able to increase their market share. Persistent cost or profit differences require some form of restricted entry, specific intangible assets or oligopolistic co-ordination. If technology or skills is easy to transfer but it is not transferred because of collusion, we have to add a cost side effect ('the staircase')stemming from the non-proliferation of the best technology- to the well-known demand side loss ('the triangle'). This paper presents a model with vertical product differentiation and develops a method which disentangles cost differences coming from vertical product differences and those coming from other sources. Data for the paper industry in the EU, in the US and in Japan indicate that cost differences are large. If at least some part of them comes from oligopolistic co-ordination, then the welfare loss of oligopoly is much larger than the usually measured demand side welfare loss.     

《中国少数民族文艺理论集成》注释误漏举隅

《中国少数民族文艺理论集成》一书的出版填补了我国文艺理论研究史上的不少空白。但由于此书成于众手，错舛之处亦在所难免．按页码顺序从该书中可拣出除刘禹锡部分（刘禹锡部分有另文论之）之外的、有明显误漏的注释十二条，并有翔实的史料可为此举证。