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采用微波消解技术处理小麦粉标准样品后,用原子吸收分光光度计测定其中镉的含量,与传统的压力罐消解所得结果进行了比较.结果表明,微波消解样品速度快,省时,试剂消耗少,而且测定的准确度也高,能明显的提高样品分析的自动化程度和速度. 相似文献
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在农产品成分分析尤其是元素含量分析中,基于测试仪器的需要,需要对样品进行预处理。不同样品中的元素赋存状态不同,样品的预处理方式会直接影响样品的均一性和代表性。目前,对不同种类的蔬菜、水果、菌类和谷物等食品类样品,选择针对性的预处理流程和参数,可以有效提高分析测试结果的准确性。为研究粉碎粒度对农产品样品测定结果的影响,本文对预处理过程中的缩分、清洗与烘干、粒度及粉碎方式进行了总结,在此基础上,选取了大米、黄豆、玉米及青稞4类农产品样品来验证不同碎样粒度对测定结果的影响,探究不同的预处理方式对食品成分分析测试结果的影响,以期对同类样品的相关研究提供参考。 相似文献
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天津市七里海滨海湿地沉积物重金属元素的空间分布特征 总被引:2,自引:0,他引:2
对七里海滨海湿地沉积物6种重金属元素进行系统分析,结果表明Cu、Zn、Pb、As、Cd 5种元素在沉积物中含量相对稳定,Hg元素在湿地沉积物中分布不均匀,变化较大。富集度分析表明,七里海滨海湿地重金属富集度划分为元素适中、轻度富集、中度富集3个级别,元素富集程度依次为Cd>Cu>Zn>Pb>Hg>As,As元素基本介于元素适中和元素贫乏之间, Cu、Zn、Pb、Hg 4种重金属达到了轻度富集,说明该区已受到轻度污染,Cd元素已到达中度富集,说明该区已受到中度污染,应引起重视。 相似文献
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目的:建立不同产地胖大海中铅、镉、砷、汞和铜含量的测定方法,了解云南、安徽和广西等不同产地胖大海中5种重金属及有害元素的差异,结合主成分分析法和聚类分析法评价不同产地胖大海的质量差异性。方法:胖大海经粉碎后,进行消解前处理,辅助气和等离子气流量分别为1.0 L·min-1和15 L·min-1,射频功率为1 550 W,蠕动泵转速为0.1 r·min-1,喷雾室温度为2.0℃,重复3次,扫描100次采集数据。结果:5种重金属及有害元素线性关系良好,r> 0.999,平均加标回收率为98.50%~99.93%,RSD为1.39%~1.99%。38批样品中,18.42%的样品Cd含量超标,21.05%的样品Cu含量超标,50%样品未检出Hg,所采集样品中Pb、As均未超标。主成分分析提取2个成分,累计贡献率为68.964%。结论:该方法可快速、准确地测定胖大海中的重金属及有害元素的残留量,主成分分析方法、聚类分析法能有效地区分不同产地的胖大海,为胖大海质量控制提供依据。该方法高效准确,可用于胖大海中重金属及有害元素的质... 相似文献
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目的:建立高效液相色谱串联质谱法测定豆芽中4-氯苯氧乙酸(4-CPA)、6-苄基腺嘌呤(6-BA)残留量的不确定度评定方法.方法:建立数学模型,分析实验过程中不确定度因素的主要来源.结果:豆芽中4-CPA含量为(9.06±0.86)μg·kg-1(k=2),6-BA含量为(9.41±0.88)μg·kg-1(k=2).... 相似文献
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目的:通过改变电感耦合等离子体质谱仪(ICP-MS)的测定模式和前处理方法,优化电感耦合等离子体质谱仪(ICP-MS)测试食品中硒的方法。方法:样品经过微波消解仪消解后添加4%异丙醇后再定容,电感耦合等离子体质谱仪(ICP-MS)设定为高能氦气模式(HE He)测试样品中硒的含量。结果:优化后的方法在检测硒的过程中,仪器灵敏度从12.69增加到842.6,灵敏度提高了66倍。标准样品中硒多平行检测结果的相对偏差从3.5%降低到0.9%。结论:电感耦合等离子体质谱仪(ICP-MS)在高能氦气模式(HE He)下,样品消解后加入4%的异丙醇上机测试的方法有效、灵敏、精确。 相似文献
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《国际粮食与农业综合企业市场学杂志》2013,25(4):29-47
Abstract This paper reports on an investigation into the convenience orientation of various food-related lifestyle segments in Ireland. The food-related lifestyle instrument developed by the Centre for research on customer relations in the food sector (MAPP Institute in Denmark) provided a valuable framework for the development of this analysis. This instrument was applied in Ireland in 2001, with a nationally representative sample of one thousand Irish consumers. Six distinct food-related lifestyle segments were identified (Ryan, 2002). The lifestyle instrument grouped consumers in terms of their attitudes towards the purchase, preparation and consumption of food products in general. This research investigates the degree to which these food-related lifestyle segments are convenience-oriented by investigating their attitudes towards convenience and their purchase frequency for a range of convenience foods. The convenience element was developed following a review of the Irish convenience food market, which highlighted a number of convenience-related food issues driving this market. This study identified the food-related lifestyle segments that were particularly convenient oriented. These segments were further explained by relating their purchase frequency for a range of convenience products. The attitudes of the various food-related lifestyle segments towards convenience foods and purchase frequencies for convenience foods differed. Three of the food-related lifestyle segments were identified as having a convenience orientation, namely the hedonistic, the extremely uninvolved and the adventurous segments. 相似文献
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基于耕地综合质量的基本农田布局优化——以河南省温县为例 总被引:8,自引:0,他引:8
研究目的:有效整合农用地分等与土地质量地球化学评估两项成果,补充完善区域基本农田布局优化方法。研究方法:运用GIS空间分析法整合农用地分等与土地质量地球化学评估两项成果,对研究区基本农田进行耕地综合质量评价。运用名特优农产品喜嗜典型元素分析法,确定基本农田布局优化方案。研究结果:温县基本农田布局优化后不仅面积增加了37 hm2,调入的基本农田利用等、肥力、环境健康、地化综合质量都大幅提高,有益元素N、P富集区面积大幅增加59.30 hm2和185.61 hm2,有害重金属元素Pb的2—3级富集区面积大幅减少195.45 hm2。研究结论:基本农田布局优化是贯彻落实"十分珍惜、合理利用土地和切实保护耕地"基本国策的重要工作;整合成果丰富了耕地综合质量的内涵,为区域土地资源的合理、高效、可持续利用提供科学依据。 相似文献
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Spyridon Mamalis 《国际粮食与农业综合企业市场学杂志》2013,25(2-3):191-206
Food service industry has expanded globally in recent years. This article provides an empirical study on the identification of the critical success factors of food service operations and the restaurant industry. Research objective was to develop factors for food service industry/restaurants in order to identify key dimensions in determining consumer choice. The primary instrument was developed through a thorough and detailed analysis of the literature followed by qualitative research. A quantitative survey with a sample of 300 participants, followed. A seven-factor, 24-item measure was extracted from the purification process. A second stage analysis followed with new data collected for the study from a sample of 400. The final structure included six factors consisting of 14 items. The factors labeled as (a) Adaptation to Locality, (b) Service, (c) Facilities, (d) Food Quality, (e) Place to Be, and (g) Sales Incentive Program. Reliability and construct validity were established using coefficient alpha measures and confirmatory factor analysis. Success factors can be used by researchers and marketing managers to help them better understand market and consumer behavior. 相似文献
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Land consolidation has been an important instrument of rural development for over a century throughout Europe. Nowadays, land consolidation can be an integral part of both rural and urban development projects, but the focus of our study is on land consolidation in rural areas. In addition to the efforts aimed at making agriculture and forestry more competitive through a comprehensive reallocation process, improvement of road and drainage networks, landscaping, environmental management, conservation projects, and other functions may be implemented in land consolidation. There are differences in the objectives and procedures of land consolidation among the countries. Beside the formal institutional framework of land consolidation, informal institutions can have a substantial influence on the implementation of land consolidation. In the article, the past experiences in the field of land consolidation in Slovenia are presented, which are still reflected in the limited acceptability of this instrument among land owners. Furthermore, the current institutional (legal) framework is analyzed in detail. The main objective of the research was to investigate the opinion of land consolidation participants about land consolidation. Based on the field survey conducted on a sample of private land owners involved in selected land consolidation projects we tried to define the advantages and disadvantages of the current practice. The main finding is that the active participation of land owners contributes to their comprehension of the aims and to their satisfaction with the results of the land consolidation. It has been shown that the active participation of land owners in the land consolidation is the basis for developing good practices; moreover, it affects the land owners’ perception of land consolidation. The transfer of knowledge and representation of good practices among actors are still needed, in particular because of bad experiences in the past (i.e. enforced and environmentally unfriendly projects) and the traditional emotional attachment to land among land owners. In parallel, there is a great need to provide an optimization of the land consolidation process in Slovenia. 相似文献
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AbstractThis paper investigates the effects of the convergence process of direct payments (DPs) on farm income inequality. The analysis uses the Gini coefficient concept and its decomposition on the FADN Italian sample in 2014 and 2019 to assess the impact of the DPs reform in Italy. Results of the analysis show that a marginal increase in direct payments will reduce income concentration. However, a shift of resources toward mountain areas could occur. The results of the analysis have some policy implications regarding the application of the convergence mechanism of the CAP in Italy: in fact, the convergence process leads to a redistribution of resources in favour of mountain areas. These results could feed the debate on the future of CAP direct payments after 2020, when the cut or, at least, the reduction of DPs could increase income concentration. 相似文献
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The present study seeks to discuss and advance the understanding of land fragmentation and land grabbing within Romania's economic historiography landmarks, depicting how the origins of the land property issues are deeply embedded politically, socially, and culturally in history and still strongly exist in today's collective mind. Scientific evidence on the perceptions and behaviors of land owners regarding land grabbing was obtained through a non-probabilistic survey. The data collection instrument was a structured questionnaire, which was applied through face-to-face interviews to a sample of 52 Romanian land owners from various regions of the country. The results show that in the land owners’ perception, if land is sold to foreigners, national security is the most vulnerable aspect. Regarding the preference for the nationality of the land buyer, the majority of the people investigated prefer to sell to a Romanian buyer, thus making a clear statement in favor of the Romanian ownership of the land. The empirical results are placed in the context of a bottom-up approach—negotiation, with a high potential, unexplored in Romania, for implementing win–win agricultural solutions. Negotiation is valued as part of the answer to land fragmentation–land grabbing, a “back and forth” matter. The study recommends several measures for land use policy, tailored according to specific Romanian conditions, such as using an open access electronic registry of foreign land acquisitions, establishing a threshold for these acquisitions, and securing the preservation of the agricultural destination of land. In a political and economic context where land fragmentation and grabbing are two realities that are hard to deny and separate, a significant implication of the research is the enrichment of knowledge related to the sources of the “chronical” nature of fragmentation and to land owners’ attitude toward land grabbing, thus contributing to the design and implementation of future integrative land use solutions. 相似文献