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131.
H. Aïchi Y. Fouad D. Causeur C. Walter 《Communications in Soil Science and Plant Analysis》2020,51(9):1253-1267
ABSTRACT Many factors could influence simultaneously soil spectra. We aimed to study the single effect of organic carbon and total iron in soil visible and short-wave near-infrared spectra and to quantify their contents. Two datasets of soil mixture samples were prepared by mixing, in various fractions, an organic carbon-rich material with a total iron-rich material and then with a total iron-poor material. For these two datasets, contents in organic carbon are quite similar but contents in total iron are significantly different. Results show that samples of the same dataset have the same overall spectral shape. Organic carbon has a decreasing effect that affects the whole spectral range without showing any specific absorption peaks. By contrast, total iron has specific absorption peaks. Spectra of the second dataset characterized by soil mixtures with higher total iron contents were more compact within the spectral bands 400–440 and 920–950 nm. Besides, continuum removal enables to exaggerate absorption peaks of wavelengths linked to total iron content. Partial Least Squares Regression (PLS R) models of both total organic carbon and total iron assign high coefficients to the wavelengths that are considered relevant and conversely low coefficients to those that are considered irrelevant. Both organic carbon content and total iron content were well predicted. For these models, coefficients of determination were superior to 0.9 and RMSE was closed to zero. The global models calibrated on all the samples demonstrated that PLS R was able to integrate sample heterogeneity. 相似文献
132.
为探讨马鹿日粮蛋白质水平和蛋白质 /代谢能比值对其产茸性能的影响 ,采用 3个蛋白质水平 (分别为Ⅰ :7 60 % ,Ⅱ :1 1 60 % ,Ⅲ :1 5 60 % )日粮的单因子设计 ,将选出的 2 0头健康和上年产茸量相近的 4岁马鹿随机分配到 3个日粮处理组中 (Ⅰ组为 8头 ,其他两组各为 6头 ) ,进行饲养试验。试验结果表明 ,蛋白质水平及蛋白质 /代谢能比值分别为 1 1 60 %、1 3 74g/MJ的日粮处理对产茸性能 (茸重、茸日增重、料茸比等 )的影响效果较好 ,但各组间差异不显著 (P >0 0 5 )。 相似文献
133.
134.
Investigations on the utilization of the generative storage potential of indeterminated field bean genotypes ( Vicia faba L.)
The gradation in seed yield between and within the inflorescences of a field bean plant results from a hierarchical control by way of internal competition in connection with hormonal regulation. Following this hypothesis in genotypes with different yielding capacity (2 inbred lines, 1 hybrid) the two proximal flowers/inflorescence of the nodes 3–6 (counted from the bottom of the plant) were either removed or treated with growth regulators. AMO-1618 was applied for inhibition of the gibberellic acid biosynthesis, or chlorflurenolmethylester (CFM) for reduction of indole-3yl acetic acid translocation as both phytohormones might be concerned with the hierarchical control of the storage system. — Independent from yield level a reduction of the used storage potential in control plants up to 50% by treatments was fully compensated for in other regions and positions of the plant. AMO-1618 application in some cases indicated an increased seed yield/plant, whereas CFM only increased the number of sterile pods/plant. These effects are discussed in relation to the storing efficiency and to yield stability of an indeterminated faba bean plant. 相似文献
The gradation in seed yield between and within the inflorescences of a field bean plant results from a hierarchical control by way of internal competition in connection with hormonal regulation. Following this hypothesis in genotypes with different yielding capacity (2 inbred lines, 1 hybrid) the two proximal flowers/inflorescence of the nodes 3–6 (counted from the bottom of the plant) were either removed or treated with growth regulators. AMO-1618 was applied for inhibition of the gibberellic acid biosynthesis, or chlorflurenolmethylester (CFM) for reduction of indole-3yl acetic acid translocation as both phytohormones might be concerned with the hierarchical control of the storage system. — Independent from yield level a reduction of the used storage potential in control plants up to 50% by treatments was fully compensated for in other regions and positions of the plant. AMO-1618 application in some cases indicated an increased seed yield/plant, whereas CFM only increased the number of sterile pods/plant. These effects are discussed in relation to the storing efficiency and to yield stability of an indeterminated faba bean plant. 相似文献
135.
针对苏里格气田采用的湿气集输工艺,对水合物的几种防治方法进行研究和对比,包括加热法、逐级节流法、添加热力学抑制剂、机械清除法。结果表明:通过现场试验,在完全掌握水合物冻堵时间规律的基础上,使用机械清除法既可以避免卡阻问题,又能有效清除水合物,防止管道冻堵,且该方法具有直接、彻底、易操作、无污染、经济等优点。基于管道运行中水合物的生成规律,提出了以机械清除法为主的水合物防治方法,并就工艺装置的改造提出建议。 相似文献
136.
几种植物对城市尾水中重金属的去除效果研究 总被引:1,自引:0,他引:1
为了筛选适合吸收城市尾水中重金属的植物品种,研究了酸模(Rumex acetosa L.)、莎草(Cyperus glomeratus L.)和空心菜(Ipomiea aquatica Forsk)3种植物对城市尾水中重金属Zn、Cu、Pb和Cd的去除效果,并以酸模为材料,研究其对人工模拟重金属Cd和Pb污染水体的适应性。结果表明:酸模、莎草、空心菜3种植物对城市尾水中Zn、Cu、Cd、Pb的去除率分别为74.33%、60.43%、45.45%、36.43%,其中酸模对重金属的去除效果最好,其次是莎草和空心菜。酸模对尾水中Zn、Cu、Cd、Pb的去除率分别达到了86.63%、90.37%、76.81%、66.67%。Cd和Pb含量分别在0.5~2.0mg/L和0.2~0.4mg/L时酸模有较好的耐性。因此,酸模更适合于城市尾水中重金属的吸收修复,且对一定质量浓度Cd和Pb表现出较好的去除效果。 相似文献
137.
138.
不同清洗方式对香菇中毒死蜱残留去除效果的研究 总被引:2,自引:0,他引:2
采用气相色谱法,研究了不同清洗方式对香菇中毒死蜱残留的去除效果。结果表明,日常使用的清洗方式,均可降低香菇中毒死蜱残留量,但去除效果存在差异,香菇中毒死蜱残留去除率在0.32%~100.00%间。采用洗涤剂清洗,对于香菇中毒死蜱残留总体去除效果最好,即使对高残留量样品(64.49 mg.kg-1)也具有较好的去除效果,去除率达54.72%~56.69%。采用流动的自来水冲洗,对于较低残留量的样品(低于3.91 mg.kg-1),去除效果最好,而对高残留量样品,去除率则低于30%。采用相同方式处理,香菇中毒死蜱去除率随着初始残留量的增大而减小;除盐水浸泡处理外,随着处理时间的延长,残留去除率增加。研究结果对于去除香菇等食用菌农药残留量,提高食用安全性,具有指导意义。 相似文献
139.
分析了皂素生产中废水的污染现状及污染特点,对皂素废水的预处理、生化处理、深度处理以及皂素的清洁生产和废弃物资源化利用几个方面的技术进行分析比较,得出皂素生产中废水处理技术的发展趋势以及废水处理仍面临的问题,提出了合理的建议. 相似文献
140.
试验以白洋淀底泥为栽培基质,用室内栽培的试验方法,研究不同营养条件下,蓖齿眼子菜的生物量变化及其对水体中氮、磷的去除效果.结果表明:随着营养等级的提高,蓖齿眼子菜生长性状良好,且生物量及其对水体总氮的去除率均呈逐渐增加趋势,当水体中总氮浓度高于10 mg/L时,蓖齿眼子菜对总氮的去除率达到最高,为63.06%;对总磷的去除率呈递减趋势,水体总磷浓度低于0.9 mg/L时,蓖齿眼子菜对总磷的去除率最高,为96.63%.同时提出更加优化的修复富营养化水体的途径. 相似文献