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References     
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This paper presents an assessment system which on the basis of quantifiable criteria and appropriate orientation values describes the risk potentials of farming as far as environmental protection and sustainability is concerned. The procedure addresses the most significant risks and suggests ranges for their tolerability. By this way farmers can recognize principal shortcomings of their management and look for appropriate countermeasures to cope with them. The guiding principle is a way of farming which uses the available resources and the production potential as efficiently as possible, while keeping the unfavorable impacts on soils, water, air and biota within acceptable limits. Several years of investigations in about 125 different farms have shown that non‐tolerable impacts of farming on the environment are predominantly due to avoidable managerial mistakes. The suggested assessment system provides criteria for the actual magnitude and the tolerability of the different risk potentials and may thus help to substantiate the compliance with such general principles as ”︁good farming practice”.  相似文献   

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江西红壤在系统分类中的参比特征研究   总被引:1,自引:0,他引:1  
《土壤通报》2019,(5):1009-1015
在江西省选取了由花岗岩、泥页岩和红砂岩发育的46个典型红壤剖面,在明确剖面形态特征及理化性质的基础上,依据《中国土壤系统分类检索(第三版)》确定了其在中国土壤系统分类中的归属,由此讨论了不同纬度带下,红壤与中国土壤系统分类单元参比关系以及气候和母质对所划分出的系统分类单元的影响。结果表明,46个典型红壤共划分为3个土纲、3个亚纲、6个土类和14个亚类,其中江西省纬度28°N以北主要归属于湿润淋溶土,26°N以南主要归属于湿润富铁土,26°~28°N赣中地区,花岗岩发育的土壤主要归属于湿润富铁土,发育于泥页岩、红砂岩的典型红壤主要归属于湿润雏形土。  相似文献   

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An integrated approach is presented for the establishment of purified protein and peptide reference standard materials suitable for both biological and chemical assays. Preliminary considerations, handling and storage conditions, and a variety of chemical methods for defining the reference standards are examined in detail. Of the chemical methods, liquid chromatography (LC), amino acid analysis, Kjeldahl protein assay, electrophoresis, and ion chromatography are key assays in determining the potency, purity, and identity of the reference standard preparation. Finally, the role of liquid chromatography in assessing reference standards for identity and chemical purity is examined and correlated with other methods.  相似文献   

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This paper describes an assessment of ecological standards for eutrophication and desiccation using the ecotoxicological approach of standard setting. In ecotoxicological risk assessment single-species toxicity data, such as No Observed Effect Concentration (NOEC), are used to extrapolate maximum tolerable concentrations (MTC) which protect 95% of the ecosystem's species. In our approach single-species data consist of the species-response function for both nutrient availability and soil moisture. These data were used to calculate the maximum levels at which 95% of the plant species are protected. A case study, using data on 275 plant species of usable grasslands in the province of South Holland, has been carried out. Ecological standards are calculated for maximum nitrogen load and changes in groundwater level. The influence of nitrogen limitation and moisture shortage on the 95% species protection level is considered. Differences in methodology between our approach and the assessment of ecological standards for micro-pollutants and critical loads are evaluated.  相似文献   

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该文探讨了设施蔬菜棚室内环境空气质量评价指标的筛选与定值原则,提出以可吸入颗粒物、二氧化硫、二氧化氮、铅、氟化物、一氧化碳、苯并[a]芘、氨气、氯气、乙烯10种污染物作为设施蔬菜棚室内环境空气质量的评价指标。参考国外相应标准,结合我国设施蔬菜生产的实际情况,提出了每种污染物的最高允许浓度。  相似文献   

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我国生态农业县、村、园区认证标准研究   总被引:1,自引:0,他引:1  
阐述了制定生态农业认证标准的背景及现实意义,具体介绍了生态农业县的7类认证指标、19项认证依据、49个评分标准,生态农业村的8类认证指标、23个认证依据、53个评分标准和生态农业园区的8类认证指标、15个认证依据、39个评分标准,剖析了各自标准的优缺点,并提出进一步改进与完善认证标准的方向.  相似文献   

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Rat bioassay was used to assess the protein quality of powdered infant formulas and to evaluate the feasibility of using modified casein diets (containing the same source and level of fat and carbohydrate contributed by the infant formulas) as reference standards. Modification of the casein diet to match the milk-based formulas caused a significant reduction in weekly protein efficiency ratios (PER) and net protein ratios (NPR) at the third and fourth weeks. Modification of the casein diet to stimulate the soy-based formulas had no significant effect on NPR values; PER values were more varied. When PER and NPR values of the powdered milk-based formulas were expressed relative to the unmodified reference standard, the relative values were lower than when each matched reference was used. With few exceptions, the relative weekly PER values of the soy-based formulas were similar regardless of the standard used. The relative NPR values of the formulas had a pattern similar to the relative PER values. The data indicate that protein quality evaluation of infant formulas using rat bioassay warrants the use of matched casein reference diets for each type of formula.  相似文献   

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A total of 236 samples of infant foods, including honey, dry cereal, nonfat dry milk, evaporated milk, canned formula, and canned baby food, were collected in the New York City area and tested for the presence of Clostridium botulinum spores. Methods for recovery of spores were validated using foods spiked with 4 spores/mL or g. None of the products contained C. botulinum spores, indicating that their incidence in these commercial foods is not widespread. This limited study did not identify any food types that could be suspected of being involved in the transmission of infant botulism.  相似文献   

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厕所革命关乎民生大计,农村厕所改造是实现乡村振兴的重要组成部分。针对农村厕所改造过程中存在厕所改造政策落实不到位、盲目选择厕所类型、粪污处理不当和厕所标准规范不完善等问题,对文献和相关材料进行查阅和梳理。从厕所改造政策发展历程、厕所改造关键技术和厕所改造标准体系及重要标准规范等3个方面对中国农村厕所改造的发展历程进行回顾和研究,提出要确保农村厕所改造的政策文件和资金落实到位、因地制宜选择农村厕所改造和粪污处理的技术与模式、修订完善现有标准规范和补充缺乏的标准内容并形成系统的农村户厕标准体系、基层政府和农村要推动常态化管理维护并形成一体化管理机制等建议,以期为中国农村厕所革命的推进提供参考。  相似文献   

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目前我国蓝莓用农药登记情况与我国对蓝莓病虫害防治的需求状况极不适应.为了提高我国蓝莓质量安全水平,本文比较了我国蓝莓用杀菌剂登记使用情况和国内外蓝莓中杀菌剂最大残留限量标准,综述了近年来我国有关防治蓝莓病害用杀菌剂的研究进展,总结了当前生产标准中推荐使用的杀菌剂品种,并对我国蓝莓病害防治用药工作提出几点建议.  相似文献   

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生物柴油性能标准分析及建立健全标准体系的建议   总被引:5,自引:0,他引:5  
针对中国生物柴油标准体系尚不健全的状况,该文分析了生物柴油的性能指标和国际上常见的生物柴油标准;对比和分析了中国的GB/T 20828-2007和欧盟的EN 14214-2005、德国的DIN V 51606和美国的ASTM D 6751-03;提出了制订中国生物柴油标准体系的建议,建议包括:完善燃料生物柴油的标准、建立生物柴油/柴油混合燃料的标准、建立燃料生物柴油生产和性能改进剂相关标准、建立生物柴油应用相关标准。  相似文献   

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Vegetable proteins are an integral part of infant weaning diets in Latin America. Protein quality in plant-based products, however, is constrained by amino acid composition and intrinsically present antinutritional factors. The goal of this study was to improve bean protein quality by utilizing fermentation and germination processing. The objectives were to determine if protein quality, as measured by Food and Agricultural Organization (FAO) approved True Protein Digestibility (TPD) and Protein Digestibility-Corrected Amino Acid Scores (PDCAAS), of formulated bean-based weaning products could be improved upon fermentation and germination and if protein quality could be further improved when processed beans were combined with cooked rice. Results showed that the highest TPD and PDCAAS values were obtained for cooked germinated beans combined with rice. The TPD values for products ranged from 80 to 91%, and the PDCAAS values were 0.38-0.51. There was no significant increase (P < 0.05) of either TPD or PDCAAS values upon fermentation. Germination increased TPD of cooked bean products; this increase was not, however, accompanied by an increase in PDCAAS. When combined with rice, the PDCAAS values for all bean products improved significantly, thus supporting the concept of cereal-legume complementation. In conclusion, this study showed the range of PDCAAS in processed black bean and bean-rice infant weaning food products. The potential for incorporation of these products into the diets of weaning age Latin American children would, however, be confirmed only after validation with growth or metabolic balance studies in human infants.  相似文献   

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Nonenzymic browning reactions in commercial infant formulas were evaluated through their furosine content as well as the isomeric disaccharides formed during processing. Lactulose was observed only in samples containing appreciable amounts of lactose, whereas maltulose was present in all samples due to the isomerization of maltose. Because formation of maltulose depends on the initial amount of maltose present, the ratio maltose/maltulose was used for comparative purposes. The ratio maltose/maltulose varied within a wide range, 27-167; therefore, low values in maltose/maltulose ratio may indicate severe processing conditions during manufacture, whereas high values may indicate mild processing conditions. Variable amounts of furosine content in samples with similar maltose/maltulose ratios may be attributed to different conditions used during storage. Levels of furosine higher than those reported for milk powder were detected in most studied samples. Determination of both furosine and maltose/maltulose ratio would yield information retrospectively about the heat treatment applied during processing and the storage conditions of commercial infant formula.  相似文献   

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The potential of hypoallergenic (HA) infant milk formulas containing hydrolyzed milk proteins as main constituents to inhibit angiotensin-converting enzyme (ACE) in vitro was investigated. Seven commercially available HA products designed for babies up to 4 months showed a potent inhibition of ACE in vitro, with IC 50 values ranging between 3.2 and 68.5 mg of nitrogen/L. For six samples of conventional milk-based infant formulas and three breast milk samples, no inhibition was observed. Inhibitory potential did not correlate with the degree of hydrolysis. Using reversed-phase high-pressure liquid chromatography (RP-HPLC) coupled to electrospray ionization-time of flight-mass spectrometry (ESI-TOF-MS), 15 peptides known to inhibit ACE were identified. Among them, the highly potent ACE inhibitor Ile-Trp (IC 50 = 0.7 microM) was detected and quantified for the first time in the HA samples, representing the most effective ACE-inhibiting peptide that has ever been detected in food items. The overall inhibitory potential of the HA infant milk formulas could partly be explained by Ile-Trp.  相似文献   

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The performance standards that accompany Gearing Up for Safety, the agricultural production safety training curriculum for youth, were designed to meet the certification testing requirements of the Agricultural Hazardous Occupations Order (AgHOs) certification training program. The AgHOs requires that certain youth who are older than 13 and younger than 16 years of age complete a prescribed training program before being eligible for employment on farms to perform certain tasks considered hazardous. These training resources will be available for implementation and can be accessed by contacting the second author. To our knowledge, up until this time, few, if any, standardized testing procedures or instruments have had the necessary psychometric evidence to support use of the resulting scores to assess the readiness of youth to meet the basic certification requirements contained in the AgHOs. This article describes the rationale, methods, and key findings from a standard-setting session held to establish minimum passing scores for a proposed testing process. The test will be used as a component of the Gearing Up for Safety certification process for youth workers seeking employment to perform job functions as specified under the AgHOs. Readers may be able to apply this standardized testing process, or similarly accepted processes, to other or future testing and certification projects involving agricultural safety and health.  相似文献   

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通过分析国外技术标准与科技研发呈现密切结合发展的趋势,指出中国技术标准与科技研发存在严重脱节的问题,总结出中国技术标准与科技研发严重脱节的原因在于企业参与标准制定的动力不足、缺乏技术成果转化为技术标准的信息传导机制等。结合中国农产品加工业的发展现状,提出促进中国农产品加工业技术标准与科技研发结合发展的具体措施。  相似文献   

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