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931.
建立了使用Waters UPLC Xevo TQ超高效液相色谱串联质谱仪检测水产品中4种硝基呋喃代谢物的分析方法。匀浆后的样品在酸性环境下水解,并用2-硝基苯甲醛衍生16h,经磷酸氢二钾提取,LMS固相萃取小柱净化后,在三重四极杆多反应监测模式下进行测定。方法采用同位素内标法定量,四种代谢物的检出限(LOD)均低于0.25μg·kg-1,线性范围在0.5μg·L~(-1)到10μg·L~(-1)间,相关系数大于0.99。在0.5、1.0和5μg·kg-1浓度下分别进行添加回收试验(n=5),回收率在75.2%~123.3%之间,相对标准偏差(RSD)小于9.4%。 相似文献
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J. P. Rodríguez M. Aro M. Coarite S.‐E. Jacobsen B. Ørting M. Sørensen C. Andreasen 《Journal of Agronomy and Crop Science》2017,203(3):254-267
Cañahua (Chenopodium pallidicaule Aellen) is a semi‐domesticated relative of quinoa (Chenopodium quinoa Willd.) with high nutritious quality. It is tolerant to frost, drought, saline soils and pests. One seed yield limitation is seed loss during the maturity stages. Two greenhouse experiments in Denmark and field experiments in Bolivia were carried out to determine seed shattering in landraces and cultivars with different growth habits. 15–21 % of the seed shattering in the fields took place whilst the plants still were flowering and 25–35 % during physiological maturity. Seed shattering varied between locations on the Bolivian Altiplano. Cañahua types with the semi‐prostrate growth (‘lasta’) had the highest seed shattering rate in the greenhouse experiments. The Umacutama landrace had lower seed shattering (1 %) than the cultivar Kullaca (7.2 %) both of the ‘lasta’ type. Under field conditions, the cultivar Illimani with the erect growth (‘saihua’) had the highest seed shattering rate (6.4–33.7 %) at both locations and at four different sowing dates. The Umacutama had the lowest rate (0.5–1.5 %). There were no significant differences between plants of the ‘lasta’ and the ‘saihua’ types. The landrace had significantly less seed loss than the cultivars. However, in the greenhouse, the landrace yield was approximately 25 % lower than the yields of the cultivars. In general, cañahua cultivars had higher yield compared to landraces, but also a higher seed shattering rate. Landraces may be used in breeding programmes to develop high‐yielding cultivars with reduced seed shattering. 相似文献
935.
为了探索植物响应细菌信号N-酰基高丝氨酸内酯(AHLs)的分子机制。本文利用二维差异凝胶电泳技术分析了3-羰基己酰基高丝氨酸内酯(3OC6-HSL)处理引起拟南芥膜蛋白质组的变化情况,结果表明3OC6-HSL共诱导53个蛋白点发生显著变化,涉及天然免疫、逆境胁迫响应、碳代谢、能量代谢、光合作用等多种生物学功能,暗示了3OC6-HSL在调控植物生长发育和抗逆性方面发挥着重要作用,可为阐明植物-细菌跨界通讯的分子机制提供更多的功能蛋白质信息。 相似文献
936.
Nitrous oxide emission from a transplanted rice field in alluvial soil as influenced by management of nitrogen fertiliser 下载免费PDF全文
We investigated nitrous oxide (N2O) emission from an irrigated rice field over two years to evaluate the management of nitrogenous fertiliser and its effect on reducing emissions. Four forms of nitrogenous fertilisers: NPK at the recommended application rate, starch–urea matrix (SUM) + PK, neem‐coated urea + PK and urea alone (urea without coating) were used. Gas samples were collected from the field at weekly intervals with the static chamber technique. N2O emissions from different treatments ranged from 11.58 to 215.81 N2O‐N μg/m2/h, and seasonal N2O emissions from 2.83 to 3.89 kg N2O‐N/ha. Compared with other fertilisers, N2O emissions were greatest after the application of the conventional NPK fertiliser. Moreover, SUM + PK reduced total N2O emissions by 22.33% (P < 0.05) compared with NPK during the rice‐growing period (P < 0.05). The results indicate a strong correlation between N2O emissions and soil organic carbon, nitrate, ammonium, above‐ and below‐ground plant biomass and photosynthesis (P < 0.05). The application of SUM + PK in rice fields is suitable as a means of reducing N2O emissions without affecting grain production. 相似文献
937.
茶文化作为中华优秀传统文化的重要组成部分,其蕴含的心理健康教育思想内容丰富且历史悠久。近年来高校大学生数量激增,学生心理健康问题层出不穷,在高职院校中尤为凸显,且高职林科类院校中艰苦专业多,当前心理健康教育方式方法出现瓶颈,效果固化。通过茶文化中积极健康的思想,结合大学生心理健康教育教学,创新教育途径,探索并找到较好的实践运用手段,提高大学生的心理健康素质,促进大学生综合水平提高,具有较好现实意义和价值。 相似文献
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Rattan LAL 《农业科学与工程前沿(英文版)》2020,7(3):251-253
Rather than a human-centric, the basic strategy of achieving Sustainable Development Goals must be focused on restoring and sustaining planetary processes. The urgency of meeting the demands of the humanity must be reconciled with the necessity of enhancing the environment. Increasing and restoring soil organic matter content of the degraded and depleted soils is critical to strengthening planetary processes. 相似文献
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