纳米力学测量系统的载荷与位移溯源校准方法研究

对纳米力学测量系统在准静态压入模式下的载荷因子、位移因子的量值溯源校准方法进行了研究。通过一组标准砝码产生标准载荷,拟合标准砝码质量和传感器输出电压得到载荷因子;利用激光干涉仪测量压针位移,拟合干涉仪位移值和传感器输出电压得到位移因子。采用标准样品对校准结果进行了试验验证,校准后的纳米力学测量系统在国际比对测量中取得了良好结果。     

一种改进的动态门限签名方案

针对WLC数字签名方案的不安全性,做了一些必要的改进.改进后的方案:只有指定的合成群秘书参与才能生成签名;而当有新成员加入或剔除违规成员时,系统本身的参数及其它成员的密钥对保持不变;系统的成员也可以用唯一的密钥对为不同群的消息签名.     

基于标志物的食品溯源技术研究进展

食品产地溯源是食品质量与安全追溯体系的重要组成部分,有利于保护原产地标志,保护地区名牌,保护特色产品,确保公平竞争,增强消费者对食品安全的信心。基于标志物的鉴别方法具有高灵敏度,高鉴别度,高通量的特点,因此在食品溯源分析中有极大的价值。本文综述了近年来几种常用基于标志物的食品溯源技术在不同种类食品中的应用研究进展,分析了各种方法的优势和不足,并展望了今后食品溯源技术研究的发展趋势,开展不同高灵敏度特征标志物的同步检测在未来食品溯源分析中更有前景。     

Influence of manufacturing conditions and discrimination of Northern Spanish cheeses using multi‐element analysis

Thirty‐three samples of cheeses belonging to different Protected Designation of Origin (PDOs) located in Northern Spain were analysed with the aim of studying the influence of processing conditions on the minerals and trace elements content in cheeses. The use of sheep milk, animal rennet, salting by immersion in a brine bath and ripening in cheeses reported, in general, the highest levels of trace elements. Moreover, pattern recognition analysis of multi‐elemental data, based on mineral and trace element content, was used to determine geographical traceability and to detect possible imitations with a correct classification in 98.5% of cases.     

The importance of transformations for traceability – A case study of lamb and lamb products

Vertical product information flow is important with regard to consumers’ perceptions of the meat which they buy. When research and analysis of traceability is carried out it is often found that critical points where information is systematically lost are encountered in the transformations of the resources. This study describes how lamb meat can be both tracked and traced through a lamb meat producer (company A). At company A 60% of the resource transformations were shown to be additions, mixing and splitting, these are considered to be those which produce the most critical traceability points. After an analysis of the current traceability system at company A suggested improvements were made. With regard to granularity of traceability they cannot trace individual animals during production, but rather a set of animals. The smallest traceable resource unit (TRU) company A can trace back to be a set of (identifiable) animals from one specific farm.     

A DNA method for qualitative identification of plant raw materials in feedstuff

This research developed a simple and not expensive DNA method for the qualitative identification of plant raw materials used as feed mixtures. Specific simple sequence tagged (STS) markers were developed to detect faba bean (Lectin A gene), field pea (Convicilin A gene), grain sorghum (UDP-glucosyltransferase gene) and barley (Hordoindoline-a gene), whereas identification of durum and common wheat (lipid transfer protein gene), soybean (Gly m Bd 30K allergen gene) and maize (invertase gene) was carried out using markers available from the literature. Cross-reactivity of the primer pairs was also checked against oat, rye, kidney bean and lentil. The method was effectively applied to the analysis of flour mixtures and extruded feedstuff. It could be included in traceability and certification of animal feeding systems within high quality animal production chains which are strictly related to the production area by the valorisation of locally grown raw materials.     

美国国家遗产廊道（区域）模式溯源及其启示

遗产廊道（区域）模式是美国立足自身文化资源特点,摸索出的一种针对大尺度文化景观的保护方法。经过30年的探索,其运作机制与保障体系已日臻成熟。该模式发展过程中,有很多经验和教训值得我国学习和借鉴。尽管近年来国内已有学者陆续对该模式进行了引介,然而由于这一模式出现的原因错综复杂,目前学界尚未做出全面、权威的论断。本文首先介绍了该模式的概况,然后详细梳理了该模式出现的时代背景、原因、重要相关事件与时间节点,接着提出该模式对我国遗产区域化保护模式的启示,最后强调我们在借鉴美国经验时,应立足现实国情,而不能盲目照搬。     

Discriminant analysis of Mediterranean pine nuts (Pinus pinea L.) from Chilean plantations by near infrared spectroscopy (NIRS)

Pinus pinea L. is one of the most important nut species in the world given the high nutritional and culinary value of its seed, the pine nuts, with increasing demand. The objective of this study was to assess the potential of visible and near infrared spectroscopy (VIS + NIRS) to analyse different sample presentations and to discriminate geographical origins of Mediterranean pine nut grown in Chile. Pine nuts were collected from 76 adult trees in three growth macrozones previously defined for stone pine in Chile. Original spectroscopic data were obtained by means of a Foss NIRSystems 6500 SYII spectrophotometer using a transport module. Reflectance was employed in the wavelength range of 400–2500 nm. The best means of sampling for the pine nuts used in this study were also studied. After analysing the spectroscopic data, discriminant models were obtained by means of discriminant partial least square (DPLS) with all samples. For the three macrozones previously identified, 87.8% of samples was correctly classified in the cross validation stage with the best model for pine nuts spectra analysis, obtained with shelled intact pine nuts. Results indicate that NIRS technology is capable of differentiating between pine nut samples of different geographical origins with errors ranging between 12.2 and 9.2%, and demonstrate the potential of VIS + NIRS technology as a rapid and accurate method for predicting the geographical origin of Mediterranean pine nuts.     

环境样品放射性测量的溯源性实践和经验

环境样品放射性测量的溯源性是测量质量保证的核心。本文叙述了与环境样品放射性测量溯源性有关的一些问题:简要介绍了溯源性的概念及其演变;总结了本实验室近几年来在环境样品放射性测量中的质量保证工作,涉及标准的传递、参考物质的制备、Ge(Li)谱仪对体源的效率的刻度、以及比对测量等溯源性实践活动。本文还讨论了溯源性的保持,并对今后工作提出了一些建议。     

Food safety and assurance: the role of information technology

The dairy industry is under pressure to improve product security, implement efficient risk management and rapid response capabilities, and manage quality 'from trough to table' to achieve full, verifiable traceability. In order to invest proactively in the future of the industry, individual processors must reassess their handling of quality and traceability data for strategic and competitive success, make appropriate physical configuration and operational adjustments, and deploy readily available technological tools to meet legislative and consumer demands, enhance product quality and increase operational efficiency and profits.