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排序方式: 共有2141条查询结果,搜索用时 15 毫秒
1.
Maria A. Ospina Monica Pizarro Thierry Tran Julien Ricci John Belalcazar Jorge L. Luna Luis F. Londoño Sandra Salazar Hernan Ceballos Dominique Dufour Luis A. Becerra Lopez-Lavalle 《International Journal of Food Science & Technology》2021,56(3):1343-1353
The objective of this study was to characterise the nutritional potential of leaves and identify a diversity centre with low cyanide and high nutrient content among 178 Latin American cassava genotypes. This field-based collection represents the seven diversity centres, held at The International Center for Tropical Agriculture (CIAT Palmira, Colombia) by the Cassava Program. The cyanide, all-trans-β-carotene and lutein concentrations in cassava leaves ranged from 346 to 7484 ppm dry basis (db), from 174–547 μg g−1 db and 15–181 μg g−1 db, respectively. Cassava leaves also showed significant levels of essential amino acids leucine, lysine, phenylalanine, valine and threonine, and average total protein content of 26.24 g 100 g−1 db. Among seven diversity centres, South American rainforest group showed low cyanide and high carotene content in leaves. In addition, VEN77 and PAN51 genotypes stood out for having low cyanide in leaves and roots and high carotene in leaves. This genetic diversity can be used to select high potential progenitors for breeding purposes. 相似文献
2.
P. Meenakshi S. E. Noorjahan R. Rajini U. Venkateswarlu C. Rose T. P. Sastry 《Bulletin of Materials Science》2002,25(1):25-29
DriedMusa paradiciaca (banana) stem and veins of the leaves, which were hitherto discarded as a waste, were collected and used as starting material
for the preparation of cellulose and cellulose acetate. This cellulose acetate was mixed with polystyrene to form blend of
cellulose acetate-polystyrene in order to provide enhanced stability and extended utility to the end products. The films of
these composites or their individual partners were made separately and studied for their mechanical properties, chemical modification
and morphological changes. We report here that banana stem is good source of cellulose and that cellulose completely undergoes
modification upon esterification. 相似文献
3.
蒋志斌 《徐州工程学院学报》2002,(1)
对新鲜茶树叶中六六六和滴滴涕共八种异构体的残留量进行测定,与同地点成品茶叶农药残留量相比较基本无差异。本法检测限为>1.8ng/g,回收率为78.2%-99.0%,相对标准偏差<10.0%。 相似文献
4.
针对叶片垂直分片机使用过程中出现的劈坏烟箱、纵向移动刀架失控和系统无报警功能等问题,分析故障产生的原因,并对其控制系统进行改进。 相似文献
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7.
银杏叶中黄酮类化合物的提取工艺研究 总被引:3,自引:0,他引:3
研究了乙醇-水体系浸取银杏叶中黄酮类化合物的工艺条件,通过分光光度法测定黄酮的含量并计算它的浸出率。根据黄酮类化合物浸出率的计算结果,选用70%乙醇溶液为提取剂,并通过正交试验给出了黄酮类化合物的最佳浸出条件:浸取温度70℃,固液比1∶20,浸取剂pH=8,银杏叶中黄酮类化合物的浸出率可达到92.2%。 相似文献
8.
S. Chevolleau J. F. Mallet E. Ucciani J. Gamisans M. Gruber 《Journal of the American Oil Chemists' Society》1992,69(12):1269-1271
Hexane and methanol leaf extracts of sixteen Mediterranean plant species were obtained by percolation. Higher yields were
observed for methanol (16.4–47.8%) than for hexane extracts (1.3–13%). Antioxidant activity of these extracts was determined
by a rapid spectrophotometric method involving the combined oxidation of beta-carotene and linoleic acid. Leaf extracts were
thus characterized by an Antioxidant Activity Coefficient (AAC) ranging from 0 to 1000. Hexane extracts gave much higher AAC
values than the corresponding methanol extracts. In both cases, myrtle (Myrtus communis) showed the best antioxidant effectiveness. 相似文献
9.
Mirela Rada Ángeles Guinda Jose Cayuela 《European Journal of Lipid Science and Technology》2007,109(11):1071-1076
Molecular distillation, or short‐path distillation (SPD), is particularly appropriate for processing of low‐volatility compounds, which are easily altered at high temperature. Olea europaea L. leaves constitute an olive tree by‐product very interesting for their natural antioxidants content. In this research, molecular distillation technology has been applied to obtain high‐value‐added compounds by the SPD fractionation of an olive tree leaf extract. The process consists of two stages: (a) ethanolic extraction of the olive leaves, followed by incorporation of the extract into glycerine and (b) molecular distillation of the glycerine enriched in olive leaf extract compounds (terpenic and phenolic compounds). Four molecular distillation tests under different conditions were carried out. Results showed that 80.9% 3,4‐dihydroxy‐phenylethanol (hydroxytyrosol) was recovered from the glycerine admixture under a pressure of 1.50–2.00 mbar, a temperature of 190 °C and a feed rate of 15 mL/min. 相似文献
10.
为了解决玉露香梨叶虫害种类多、扩散速度快、人工识别梨叶虫害耗时长的问题,提出了能够在自然环境下对玉露香梨叶虫害图像自动识别的Tiny-Alexnet卷积神经网络(Tiny-Alexnet Convolution Neural Network,TACNN)的虫害识别模型。分析了Alexnet模型的网络结构,并将实地采集的玉露香叶片虫害图像进行统一处理,为避免全连接层卷积核参数过大而产生的过拟合现象,通过优化全连接层,设置不同神经元节点和实验参数,得出了Mid-Alexnet、TACNN两种虫害识别模型。实验结果表明:TACNN较Alexnet和Mid-Alexnet模型有较高的识别准确率,该模型能够有效地提取梨叶虫害特征,类别平均准确率为81.18%,实现了对金龟子、梨木虱、梨瘿蚊三种虫害的准确区分。该模型在玉露香梨叶虫害识别方面具有良好的性能,可实现自然环境下玉露香梨叶虫害的精准识别。 相似文献