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301.
洋槐叶和槐花中营养成分分析的研究 总被引:5,自引:0,他引:5
用现代仪器分析方法对洋槐花和槐叶中蛋白质、还原糖、总糖、抗坏血酸、氨基态氮含量及微量元素含量进行了测试,并对其作为饲料的价值进行了分析。结果显示,洋槐花和槐叶作为饲料资源具有良好的应用前景。 相似文献
302.
Preparation and Properties of Biodegradable Spent Tea Leaf Powder/Poly(Propylene Carbonate) Composite Films 总被引:1,自引:0,他引:1
Guangmei Xia C. Uma Maheswari J. Jayaramudu Jinming Zhang Jun Zhang 《International Journal of Polymer Analysis and Characterization》2015,20(4):377-387
The aim of the present work is to develop novel bio-based lightweight material with improved tensile and thermal properties. Spent tea leaf powder (STLP) was used as a filler to improve the tensile and thermal properties of polypropylene carbonate (PPC). Tea is an important material used in hotels and households, and spent tea leaf is a resulting solid waste. Composite films with STLP were obtained by the solution casting method. These films were characterized by optical and scanning electron microscopy, Fourier transform-infrared spectroscopy, thermogravimetric analysis, and tensile testing to examine the effect of filler content on the properties of the composites. The results showed that composite films have increased tensile strength due to enhanced interfacial adhesion between the filler and the matrix. In addition, the composite films also exhibited higher thermal degradation temperatures than pure polypropylene carbonate. The morphology results indicate that there is a good interface interaction between STLP and PPC. Results of the study reveal STLP to be a promising green filler for polymer plastics. 相似文献
303.
Sony George S Ajikumaran Nair Ramaswamy Venkataraman 《Natural product research》2015,29(20):1959-1962
Melicope denhamii leaf volatile oil was isolated by hydrodistillation, and twenty-six constituents comprising 95.95% of the leaf oil were characterised by gas chromatographic techniques. Sesquiterpenes, zierone (22.49%) and α-gurjunene (19.96%), were identified as the major components. M. denhamii leaf oil tested against Gram-positive and Gram-negative bacteria showed significant activity against Bacillus subtilis and Escherichia coli. Anticancer activity of M. denhamii leaf oil against Dalton's lymphoma ascites cells was assessed by trypan blue exclusion and MTT assays, and the oil showed significant cytotoxicity at CD50 of 12.2 μg/mL. Induction of apoptosis on DLA cells by M. denhamii leaf oil was confirmed by morphological observation, nuclear damage and comet assays. 相似文献
304.
气相色谱-质谱法定性定量分析烟叶挥发性香气成分 总被引:1,自引:0,他引:1
本文研究了质谱去卷积算法在化合物结构定性中的作用。采用质谱去卷积和质谱库检索、色谱保留指数、标样定性等相结合的方法从烟叶样品中鉴定出118个挥发性香气成分,其中57个醛酮类化合物、23个醇类化合物、16个含氮类化合物、7个有机酸类化合物、15个其它化合物。采用定量离子进行定量,有效降低了重叠峰干扰,使色谱积分结果更为真实准确。对所鉴定的化合物进行重复性考察,结果表明有60.2%的化合物的相对标准偏差(RSD)小于20%,80.5%的化合物的RSD小于30%。线性响应考察结果表明有80个化合物的线性相关系数(R2)在0.90以上,适合于定性或定量分析。 相似文献
305.
Munish Kumar Sharma Sandip Roy Kartic Chandra Khilar 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,346(1-3):123-129
Select applications of hydrophobic nanocomposites include preparation of robust self-cleaning surfaces, water-repellent glass surfaces, and waterproofing textiles. Various nanocomposites have been reported in the literature; however, the relationship between the nanocomposite surface morphology and its hydrophobicity needs to be understood better. In the present work Fe2O3 nanoparticles and poly ethyl metha acrylate (PEMA) were used in varying proportions to obtain a series of model hydrophobic surfaces (spin-coated on glass substrate). The hydrophobicity of these surfaces was measured by static contact angle; a maximum of 103° was obtained at highest loading of iron oxide nanoparticles. These surfaces were also characterized using AFM. The contact angle and characterization data were used to test some of the models which have been proposed in the recent literature on prediction of contact angle for composite surfaces. It is proposed that the hydrophobicity of the iron oxide–PEMA surface is due to the physical roughness causing air entrapment as well as the chemical heterogeneity. Based on the experimental studies and the simulations using the recent models on contact angle, some general features of relationship between a composite surface morphology and its hydrophobicity is proposed. 相似文献
306.
用GC-MS法分析柿树叶中的脂肪酸 总被引:9,自引:1,他引:9
用乙醚-己烷混合溶剂抽提柿树叶中的脂肪酸,NaOH-CH3OH交换法甲酯化,毛细管柱FFAP作为分离柱,进行气相色谱-质谱法测定脂肪酸(以甲酯的形式)的组成。共分离出21种脂肪酸,鉴定出19种,占总含量的98.72%,其中以肉豆蔻酸(6.68%)、棕榈酸(30.00%)、硬脂酸(10.42%)、十六碳三烯酸(1.44%)、亚油酸(1.84%)、十八碳-烯酸(22.22%)、亚麻酸(1.25%)、花 相似文献
307.
308.
309.
Shengxin Yin Yuqi Mei Lifang Wei Lisi Zou Zhichen Cai Nan Wu Jiahuan Yuan Xunhong Liu Haitao Ge Dianguang Wang Dandan Wang 《Molecules (Basel, Switzerland)》2021,26(7)
Abelmoschus manihot (L.) Medic (AM), called Huangshukui in Chinese, is a widely used medicinal plant. Each part of AM has medicinal value, including Abelmoschi Radix (AR), Abelmoschi Herba (AH), Abelmoschi Folium (AF), Abelmoschi Corolla (AC), and Abelmoschi Semen (AS). However, only AC is documented in the Chinese Pharmacopoeia. In order to investigate whether there is any difference between AC and the other parts of AM, an analytical method based on ultra-fast performance liquid chromatography coupled with triple quadrupole-linear ion trap mass spectrometry (UFLC-QTRAP-MS/MS) was established for the simultaneous determination of 35 constituents in different parts of AM. Moreover, principal components analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were applied to classify and evaluate the different parts of AM based on the content of the 35 constituents. The total contents of the 35 constituents in AC were significantly higher than in the other parts of AM and the results revealed significant differences between AC and the other parts of AM. Eight constituents were remarkably related to the sample classifications. This research does not just provide the basic information for revealing the distribution patterns in different parts of AM from the same origin, but also complements some of the scientific data for the comprehensive quality evaluation of AC. 相似文献
310.