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排序方式: 共有260条查询结果,搜索用时 15 毫秒
81.
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。 相似文献
82.
《Food Control》2017
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. 相似文献
83.
Identification of the information to be recorded is the most important requirement for developing an effective traceability system. In this paper, we present a soybean value chain and model the information capture by three links in the chain including the farming, bulk handling and processing sectors. Internal information capture points were identified for each sector and the corresponding traceability information to be recorded was determined. In-depth analyses were conducted for a soybean elevator and an oil and meal processor to determine the importance of traceability information from their perspective. A lot of information is available at different links in the soybean value chain. The method presented here can be used to create a standardized list of data elements that need to be recorded internally or exchanged with other links in the chain. A UML class diagram is developed to represent a method for modeling the product, process, quality and transformation information at any link in the chain. Finally, some suitable technologies for electronic information exchange within the food supply chains are presented. 相似文献
84.
Palmiro Poltronieri Oscar Fernando D’Urso Giuseppe Blaiotta Maria Morea 《Food Analytical Methods》2008,1(3):171-180
Dot blot and deoxyribonucleic acid (DNA) array hybridization assays for the traceability of Lactobacillus species in food have been developed to monitor and validate typical food products. A primer set was designed to amplify the
540-bp region located at +157 of the tuf (Elongation factor Tu) gene of the Lactobacillus genus. An oligonucleotide array, containing 73 Lactobacillus species-specific tuf sequences representing 21 species, was developed and tested for identifying L. paracasei, L. rhamnosus, L. plantarum, and L. buchneri. We also tested a rapid screening method for monitoring the species present in airy samples. Dot blot hybridization identified
polymerase chain reaction amplicons immobilized on nylon membranes, using six tuf-based cyanine-3-labeled 18-mer oligonucleotides, specific for L. paracasei, L. zeae, L. fermentum, L. plantarum, L. rhamnosus, and L. buchneri. This method discriminates between multiple species of Lactobacilli isolated directly from cheese samples, simultaneously.
The tuf gene sequences, verified here with the DNA array method and used in dot blot hybridization, were shown to be a reliable tool
for the simultaneous detection and differentiation of four Lactobacillus species. The hybridization techniques developed in this study may be useful in food processing and the analysis of food origin
traceability. 相似文献
85.
Philip G. Crandall Corliss A. O'Bryan Dinesh Babu Nathan Jarvis Mike L. Davis Michael Buser Brian Adam John Marcy Steven C. Ricke 《Meat science》2013
Traceability through the entire food supply chain from conception to consumption is a pressing need for the food industry, consumers and government regulators. A robust, whole-chain traceability system is needed that will effectively address food quality, food safety and food defense issues by providing real-time, transparent and reliable information from beef production through slaughter and distribution to the consumer. Traceability is an expanding part of the food safety continuum that minimizes the risk of foodborne diseases, assures quality and cold-chain integrity. Traceability can be a positive competitive marketing edge for beef producers who can verify specific quality attributes such as humane production or grass fed or Certified Organic. In this review we address the benefits as well as the remaining issues for whole-chain traceability in the beef industry, with particular focus on ground beef for the markets in the United States. 相似文献
86.
为加强中国的食品追溯管理,并为中国食品追溯管理提供依据,综述了欧盟、新西兰、加拿大等国家和地区已经建立的食品可追溯性体系及其存在的不足,分析了中国已开展的食品可追溯性管理方面的工作,并结合中国在该方面工作存在的问题,提出了下一步加强食品追溯管理工作的建议。 相似文献
87.
RAFAEL MORENO‐ROJAS FERNANDO CÁMARA‐MARTOS PEDRO JOSÉ SÁNCHEZ‐SEGARRA MANUEL ÁNGEL AMARO‐LÓPEZ 《International Journal of Dairy Technology》2012,65(4):594-602
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. 相似文献
88.
89.
Consumer perceptions of traceability: A cross-national comparison of the associated benefits 总被引:4,自引:0,他引:4
Wendy van Rijswijk Lynn J. Frewer Davide Menozzi Giusi Faioli 《Food quality and preference》2008,19(5):452-464
Consumer perceptions regarding traceability were investigated by means-end-chain laddering. Consumers in four European countries were questioned about the benefits they associate with traceability related attributes. The benefits consumers associate with traceability are in terms of health, quality, safety and control, of which the latter was associated with trust and confidence. These benefits were similarly important in the countries investigated. Cross-national differences were also observed. Importantly, both quality and safety were shown to be related to traceability in the consumers′ minds with quality implying safety. The results show that traceability may contribute to improving consumer confidence. The most important aspects of traceability which should be incorporated into communication with consumers are discussed. 相似文献
90.
环境样品放射性测量的溯源性实践和经验 总被引:3,自引:3,他引:0
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。 相似文献