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本实验以新鲜的宁陵金顶谢花酥梨为原料,通过自然发酵、酵母菌发酵、乳酸菌发酵制作梨酵素,对比切丁处理和打浆处理对梨酵素发酵过程中理化指标和抗氧化活性的影响.结果表明,切丁处理后,酵母菌发酵优于自然发酵和乳酸菌发酵,梨酵素的还原力为2.40,多酚含量为35.57 mg·mL-1,羟自由基清除率为90.35%,DPPH自由基... 相似文献
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建立了异菌脲在梨和土壤中气相色谱分析方法。梨、土壤样品用乙腈提取,Florisil固相萃取小柱净化,淋出液浓缩后用正己烷定容,气相色谱仪电子捕获器检测。试验结果表明,异菌脲的含量与峰面积之间呈线性关系,异菌脲的最小检出量为0.005ng。对于梨样本,异菌脲最低检测量为0.01mg/kg,添加平均回收率为94%~107%,变异系数为3.2%~6.5%;对于土壤样本,异菌脲最低检测量为0.01mg/kg,添加平均回收率为98%~110%,变异系数为4.0%~10.5%。结果表明该残留分析方法的灵敏度、准确度、精密度等均符合农药残留检测的要求。 相似文献
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目的 建立京津冀地区梨始花期模拟模型,对梨树花期内冻害发生特征进行分析,为当地梨的生产管理和冻害风险防范提供支撑。方法 文章基于春暖模型构建京津冀地区梨始花期模拟模型,结合1980—2020年该地区171个气象站逐日气温数据,重构各站点逐年梨始花期,研究梨树花期冻害发生特征。结果 (1)构建的梨始花期模拟模型能较好地模拟各物候观测站点的梨始花期年际变化,模型内部检验和交叉检验的均方根误差的平均值分别为2.10 d和2.85 d,决定系数的平均值分别为0.87和0.75,该模型可推广到研究区其他站点;(2)研究区梨始花期日序自南向北逐渐推迟,各站点多年平均始花期在4月2日至5月19日;1980—2020年梨始花期呈现出显著提前的趋势,各站点提前趋势在0.4~5.3d/10年;(3)研究区梨树花期内轻、中、重度冻害频次均呈现出北多南少的空间分布,且41年间大多站点表现为增多的趋势。结论 全球变暖背景下,京津冀地区梨树始花期有所提前,花期内冻害增多,仍需对梨树花期冻害加强防范。研究结果可以指导当地梨树种植和提供防灾减灾政策支撑。 相似文献
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The negative impacts of invasive alien species on the environment are well documented. However, despite the predominantly negative perceptions associated with invasive species, it is evident that a number of these plants have been part of the landscape for generations and have numerous commercial and non-market uses. Consequently, there is a need for research that considers the impact of invasive species on the livelihoods and well-being of local communities. The authors investigated the contribution that the trade in prickly pear (Opuntia ficus-indica), an invasive alien species, makes to the household income streams of poor trading households. The research highlights the apparent conflict of interests and trade-offs that exists between local traders, for whom the sale of the prickly pear provides a livelihood source, and the South African Government, who are actively seeking to remove the plant from the landscape. 相似文献
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Traceability adoption at the farm level: An empirical analysis of the Portuguese pear industry 总被引:1,自引:0,他引:1
Traceability is becoming a condition to operate in European food markets. Retailers impose more stringent standards than what is mandatory. An example is EurepGAP, a quality standard for good agricultural practices that imposes traceability as a main obligation. This research investigates the choice of traceability at the farm level in the Portuguese pear industry. Results suggest that in this industry farm-level adoption of EurepGAP traceability is best explained by the choice to sell to the United Kingdom (UK). For farmers selling to the UK, the odds of choosing the EurepGAP traceability level are significantly linked to membership in particular producer organizations, farm productivity, producing products under a protected designation of origin (PDO), and farmer’s age. While retailers and farmer organizations seem to drive traceability, policy adjustments may be required to reduce adoption costs upstream and extend compliance among producers that sell directly to consumers and market independently. 相似文献
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本文以金秋梨为试验材料,研究1%的壳聚糖溶液浸泡处理对鲜切金秋梨的防褐变效果.试验中用壳聚糖对鲜切金秋梨进行处理,晾干后用保鲜膜包裹,置于4℃下贮藏,每2 d测定维生素含量、总酚含量、多酚氧化酶(PPO)和过氧化物酶(POD)活性,贮藏末期(12 d),对褐变指数进行测定.结果表明,壳聚糖处理能够延缓金秋梨贮藏过程中维... 相似文献
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利用数字高程模型(DEM)、土壤数据、土地利用数据并借助GIS与数学模型对永商镇早熟梨用地适宜性进行了综合评价.结果表明,永商镇适宜种植早熟梨的用地面积约435.28hm2,占农业用地总面积的25.21%.借助GIS软件和适宜性最小耗费表面模型对早熟梨种植用地的空间分布进行了分析,当最大拓展宽度达到56m时,符合农业规划中多目标模型要求的333.33hm2种植规模. 相似文献