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1.
The wood powder ofTetracentron Sinense Olive was extracted with the benzene and alcohol (2:1 v/v). Then, the extractive is analyzed in Gc and Gc-Ms. Twenty chemical
constitutions of the extractive are separated and identified, which are as follows: calamenene; 2.6,10-trimethyldihexyl; 3-methoxybenzaldehyde;
Methyl-4-methox-ybenzoate; 4-methoxyphenylacetone; 3.4-dimethoxybenzaldehyde; 3.4-dimethoxyhypnone; methyl-3.4-dimethoxybenzoate; Methyl-4-methoxyphenylacrylate;
4,4′-dimethoxycabonyl-diphenylethane; Methyl-3, 4,5-erimethoxybenzoate; Methyl-3.4-dimethoxyphenylacrylate; Methyl-myristate;
Methyl-palmate; Methyl-zoomarate; Methyl-stearate; Methyl-oleate; Methyl-arachidate; Methyl-behenate; Dimethylazelate. 相似文献
2.
On the effectiveness of four new organic fungicides against two smut-fungus species of wheat [
Ustilago tritici
(Pers.) and
Tilletia tritici
(Bjerk.)]
Field experiments in two areals in Iran proved the effectivness of 4 organic fungicides: Vitavax [2,3 Dihydro-5-carboxanilido-6-methyl-1,4-oxathilin], Derosal [2-(Methoxy-carbonylamino)-benzimidazol], Thiophamine [Methyl-4-(2-aminophenyl)-3-thioallophanate] and Cercobin-M [1,2-bis-(3-Methylxycarbonyl-2-thioureido)-benzol] against the stone-smut-fungus (Tilletia tritici) and the flight-smut-fungus (Ustilago tritici) of wheat. At GorganTilletia was destroyed totally by all of the substances named. At Karadj Vitavax caused only 70–90% reduction compared with the three other products which reached 90–100%.Ustilago was controlled only at Karadj. Here Vitavax caused 60% reduction whereas the three other preparations reached 85–95%. 相似文献
3.
马尾松木材化学组分的遗传控制及对木材育种的意义 总被引：10，自引：0，他引：10
本文利用 1 3年生马尾松子代测定林的 2 0个自由授粉家系的木材试样 ,着重研究木材化学组分的遗传学问题。研究结果表明 ,木材化学组分、基本密度和生长性状在家系间的差异都达到了极显著水平 ,并受中等至强度的遗传控制。在 6个木材化学组分中 ,灰分、戊聚糖和 1 %NaOH抽出物含量的遗传力较高 ,木质素、综纤维素和热水抽出物含量的遗传力稍低。生长性状与木材密度呈显著的负相关 ,而与木材化学组分相关性很小 ,似相互独立。遗传相关认为灰分和热水抽出物含量可分别作为综纤维素和木质素的间接选择指标。由于综纤维素和木质素含量在家系间的绝对差异较小 ,仅为 2 %～ 3% ,对选育的实际意义不大。可选择综纤维素含量高的优株进行无性繁殖加以利用 相似文献
4.
5.
The extractive of shirakamba (Betula platyphylla Sukatchev var.japonica Hara) leaves was investigated. Four glucosides ofp-hydroxyphenyl derivatives were isolated, and their structures were indentified as betuloside (I), 3,4-dihydroxy-propiophenone-3--d-glucopyranoside (II), salidroside (III), and arbutin (IV). Arbutin was newly found in the leaves of shirakamba. 相似文献
6.
从绿茶叶中提取茶多酚的工艺方法 总被引：13，自引：0，他引：13
介绍了以绿茶叶为原料提取茶多酚的工艺方法。该工艺与传统的提取方法相比，具有工艺简便、成本低、提取率高，节省时间、溶剂和能源，无毒无污染，易于大规模工业化生产等优点 相似文献
7.
银杏,杉木,杨树叶中磷脂酰甘油分子种的高效液相色谱分析 总被引：2，自引：0，他引：2
用高效液相色谱分析方法，在碳十八柱上，以乙腈－异丙醇为流动相，分析了银杏、杉木、杨树叶中磷脂酰甘油的分子种组成。分析采用磷脂酰甘油经磷脂酶Ｃ水解后，用３，５－二硝基苯甲酰氯衍生，再进行高效液相色谱分离的方法。分子种根据文献的相对保留值、标样的实验保留值、分析样ＨＰＬＣ峰的脂肪酸组成分析而确定。分析结果表明，三种林木叶中磷脂酰甘油均主要由八个分子种组成，在八个分子种的相对含量上，树种间存在明显差异。 相似文献
8.
The cardiovascular activity of the aqueous fraction of the hydroalcoholic extract of Sida cordifolia leaves (AFSC) was evaluated. In normotensive non-anaesthetized rats was observed that AFSC (5, 10, 20, 30 and 40 mg/kg, i.v.) induced hypotension (6 +/- 2%; 8 +/- 2%; 11 +/- 2%; 19 +/- 3% and 33 +/- 3%, respectively) and bradycardia (0.3 +/- 3%; 13 +/- 4%; 38 +/- 6%; 64 +/- 7% and 80 +/- 5%, respectively). Hypotensive response was completely abolished after atropine (2 mg/kg; i.v.) but potentialized after hexamethonium (20 mg/kg; i.v.) (12 +/- 2%; 21 +/- 5%; 28 +/- 3%; 32 +/- 2% and 32 +/- 3%, respectively), while bradycardic response was completely abolished after atropine (2 mg/kg; i.v.) and attenuated with hexamethonium (20 mg/kg; i.v.) (1 +/- 0.3%; 5 +/- 1%; 7 +/- 1%; 7 +/- 1% and 10 +/- 1%, respectively). In hexamethonium treated rats, L-NAME significantly attenuated the hypotensive response (9 +/- 2%; 14 +/- 1%; 16 +/- 1%; 16 +/- 2% and 22 +/- 3%, respectively). In normotensive anaesthetized and vagotomized rats, hypotensive and bradycardic responses were significantly attenuated (0.5 +/- 0.2%; 1 +/- 0.4%; 3 +/- 0.6%; 4 +/- 0.8% and 6 +/- 1%, respectively, n = 6, and 7 +/- 2%; 12 +/- 5%; 15 +/- 2%, 17 +/- 2% and 25 +/- 3%, respectively). The anaesthesia with sodium thiopental did not affect the AFSC-induced responses when compared with those induced in non-anaesthetized rats (data not showed). In conclusion, the results obtained so far show that AFSC produce hypotension and bradycardia, mainly due to a direct stimulation of the endothelial vascular muscarinic receptor and indirect cardiac muscarinic activation, respectively. 相似文献
9.
In order to examine correlations among the properties of tree species and to quantify the relationships between these properties
and flammability, the properties of 20 tree species, consisting of heat of combustion, extractive contents, ash content, moisture
content and basic density, were measured via experimental methods. In the first instance, the results show that, there are
significant correlations between heat of combustion and extractive contents, ash content and basic density. Second, heat of
combustion can be presented effectively in terms of linear regression models with extractive contents and ash content as independent
variables. Third, a flammable model was developed based on four properties of tree species as independent variables, i.e.,
heat of combustion, extractive contents, ash content and moisture content. Finally, the flammability of 20 tree species is
compared, ordered and ranked based on this flammable model. The conclusion is that flammability can be predicted from properties
of tree species, which are significantly correlated among themselves.
__________
Translated from Forest Resources Management, 2008, 4: 83–88 [译自:林业资源管理] 相似文献
10.
在重庆市城口县咸宜乡苗圃和中国林科院温室开展崖柏扦插繁殖试验,研究采穗母树年龄、不同激素种类及其组合、激素浓度、扦插基质、物理促根等不同处理方式下崖柏扦插生根效应.结果表明:(1)在咸宜乡苗圃,采用自动喷雾设施,以蛭石-泥炭土-珍珠岩(1∶1∶1)为扦插基质,用3种激素和清水处理崖柏幼树1年生枝条,扦插后160d的生根率为74.76％～96.70％,不同处理组合生根效应具有显著差异,2000 mg· L-1 IBA＞清水对照(CK)＞1 000mg·L-1 IBA＞1 000 mg·L-1IBA+ 500 mg· L-1NAA;(2)在林科院温室用2种激素和清水处理崖柏幼树1年生枝条,扦插于蛭石-泥炭土-珍珠岩(1∶1∶1)的基质,搭塑料拱棚,扦插后120 d的生根率远低于咸宜乡苗圃,为25.93％～45.37％,激素处理后的枝条与对照差异显著,1 000 mg·L-1 IBA+ 50 mg·L-1 NAA=2 000 mg·L-1 IBA＞清水对照(CK);(3)在咸宜乡苗圃用不同激素和物理促生根方法组成的27种组合处理的成年崖柏枝条,最高生根率仅为20.83％.生根率超过10％的处理组合是:清水处理,泥炭土∶蛭石∶珍珠岩(1∶1∶1);1 000 mg·L-1IBA+500 mg·L-NAA,泥炭土∶珍珠岩(2∶1);1 000 mg·L-1IBA,泥炭土∶蛭石∶珍珠岩(1∶1∶1),流水冲洗. 相似文献
11.
The methanol extractives from western red cedar mechanical pulps were found to be radically different in composition to the
extractives obtained from the heartwood. The major heartwood extractive components, the tropolones and lignans, were not present
in the extractives from the pulps. However, the proportion of a brown polymer doubled. The low and high molecular weight methanol
extractives components from the pulps were separated using methyl tert-butyl ether. The low molecular fraction contained mostly
guaiacyl-based compounds with dihydroquercetin, thujic acid, 3-hydroxy-1-(4′-hydroxy-3′-methoxyphenyl)-2-oxopropane and 4-ethyl-2-methoxy-6-hydroxyphenol
being positively identified. The brown polymeric portion had molecular weights ranging from 1,000 to 10,000. Infrared analysis
indicated that the polymers were formed from lignans. Examination of the changes in diffuse reflectance UV-visible and infra
red spectra of the pulps on extraction with methanol, suggested that the colour resides in insoluble polymers formed from
plicatic acid/plicatin during refining.
Received 18 December 1998 相似文献
12.
中国珍稀濒危荒漠植物保护等级的定量研究 总被引：29，自引：1，他引：29
本文以中国西北荒漠地区５０种荒漠植物作为定理研究的对象，根据次分析法（Analytical Hierarchy Process，简称ＡＨＰ）理论，选取珍稀濒危荒漠植物的分布区、分类学地位、生物学指标及利用价值４个指标，将生物学指标量化为乔木、灌木、多年生草本和１年生草本４个指标变量，将利用价值量化为科研、药用、饲（食）用、薪炭用和其它价值５个指标变量，分别构建判断矩阵，通过计算机数据处理，定量研究各指标在珍稀濒危等级综合评价中的以重及重要程度，研究结果表明：对５０种珍稀濒危荒漠植物的保护等级进行排序，结论基本符合《中国珍稀濒危保护植物名录》和《中国植物红皮书》的分级结果。盐桦（Betula holophila)、矮沙冬青（Ammopiptanthus nanus)、贺兰山丁香（Syringa pinnatifolia var.alashanica)、沙生柽柳（Tamarix taklamakanensis)、四合木（Tetraena mogolica)、新疆丽豆（Colophaca soongoria)、喀什女蒿（Hippolytia kaschgarica)７种荒漠植物被列为１级保护，占总数的１４％，裸果木等２２种荒漠植物被列为２级保护,贴总数的４４％，梭梭等１９种荒漠植物被列为３级保护，占总数的３８％，星毛短舌菊、盐豆木２种荒漠植物被列为等外，占总数的４％。 相似文献
13.
14.
松针内含物与马尾松毛虫生存发育关系的研究 总被引：10，自引：4，他引：10
本文用不同松树松针饲养马尾松毛虫,其结果与松针内含物的关系,经计算得出累计死亡率、化蛹率、羽化率、每个雌虫平均产卵率、周限增长率以及硬脂酸、油酸等14种。同时得出:维生素B_6(x_(13))对马尾松毛虫的化蛹、羽化和周限增长率的影响是第一位的重要因素,低沸点物质(x_8)包括萜烯类物质是影响马尾松毛虫化蛹、羽化的第二因子,苏氨酸(x_(21))是第三个因子。异亮氨酸(x_(22))是影响马尾松毛虫产卵量的第一重要因子,蛋氨酸(x_(20))是第二重要因子,维生素B_6是第三个重要因子。 相似文献
15.
杨树种子粒小、种皮薄、含水量高,在一般条件下贮藏两个月即丧失发芽能力,生产上均采用随采随播的方法。由于杨树结实有周期性,为了增加苗木当年生长量,提高苗木质量需进行春播,于是,杨树种子贮藏技术的研究不仅在生产上有着重要意义,而且对延长小粒种子寿命的探索亦具有一定价值。我们从1980年开始对杨树种子进行了不同采种期、不同贮藏方法等多项试验研究,其目的在于确定小叶杨种子的最佳采种期、最优贮藏条件,探索采种期及贮藏方法的不同对种子品质的影响,并欲从中了解它们的相关性。 相似文献
16.
J. Dorado T. A. van Beek F. W. Claassen R. Sierra-Alvarez 《Wood Science and Technology》2001,35(1-2):117-125
The white-rot fungi Trametes versicolor and Bjerkandera spp. are among the most frequent decomposers of angiosperm wood in forest ecosystems and in wood products in service. Wood extractives
have a major impact on wood properties and wood utilization. This work evaluated the ability of two white-rot fungal strains
(Bjerkandera sp. strain BOS55 and T. versicolor strain LaVec94-6) to degrade the main lipophilic extractive constituents in Scots pine (Pinus sylvestris L.). The time course of wood decay and wood extractive degradation was monitored in stationary batch assays incubated for
eight weeks. The strains tested eliminated high levels of total resin, 34 to 51% in two weeks. Wood triglycerides were the
most readily degraded extractive components (over 93% elimination in only two weeks). Free fatty acids and resin acids, which
are potential fungal inhibitors, were also rapidly decomposed by the fungal strains. Sterols were used more slowly, nonetheless,
the fungal degradation of this extractive fraction ranged from 50 to 88% after four weeks.
Received 19 March 1999 相似文献
17.
采集了常见制浆材(桉木、相思木及杨木)样品的近红外光谱,测定了样品的基本密度、综纤维素、木质素和苯醇抽出物含量,用人为控制水分的方法测定了样品的水分含量。对原始光谱进行预处理后,分别运用偏最小二乘法(PLS)、LASSO算法、支持向量机法(SVR)和人工神经网络法(BP-ANN)建立基本密度、水分含量、综纤维素、木质素和苯醇抽出物含量的预测模型。对预测模型进行独立验证,结果显示:LASSO算法建立的基本密度和综纤维素模型性能最优,其预测均方根误差(RMSEP)分别为0.006 3 g/cm~3和0.49%,绝对偏差(AD)范围分别为-0.008 8~0.009 6 g/cm~3和-0.85%~0.87%;PLS建立的水分含量模型及苯醇抽出物模型最优,RMSEP值分别为1.21%和0.24%,AD范围分别为-1.99%~2.03%和-0.35%~0.38%;SVR建立的木质素模型最优,RMSEP值为0.43%,AD范围为-0.76%~0.74%,均满足制浆造纸工业中对误差的要求。 相似文献
18.
利用3个22年生马尾松初级种子园自由授粉家系1.3 m、5.3 m和10.0 m 3个高度圆盘,研究3个家系纵向木材化学组分的变化规律。结果表明:综纤维、酸不溶木素、冷水抽提物、热水抽提物、苯醇抽提物、1%NaOH抽提物、灰分和水分等8个化学组分含量指标在树干纵向高度间差异显著。纤维素、综纤维、酸不溶木素、热水抽提物、苯醇抽提物、1%NaOH抽提物、灰分和水分等8个化学组分含量均随着树干高度的增加不断下降。混合取样数据接近整株化学组分的平均水平,因而宜采用混合样分析马尾松化学组分变化。不同家系木材化学组分的纵向均匀性以169号最好,159次之,162最差。 相似文献
19.
沙芥全草总黄酮提取方法及含量测定的研究 总被引：13，自引：0，他引：13
本文采用碱提酸沉法、超声波提取法、甲醇直接提取法、乙醇提取法和热水浸提法对沙芥全草总黄酮进行了提取方法的选择,同时采用硝酸铝比色法进行了总黄酮含量的测定,结果表明:(1)各种方法的提取效率依次为:碱提酸沉法>超声波提取法>甲醇直接提取法>乙醇提取法>热水浸提法;(2)碱提酸沉法提取沙芥总黄酮的提取效率较高,其精密度好,回收率高,适合对沙芥总黄酮的提取,同时采用硝酸铝比色法对总黄酮含量进行测定,其精密度也较高,并测得沙芥全草总黄酮含量为4.8049mg/g,证明其是一种值得开发的药用植物资源。 相似文献
20.
记述了采自广西隆林县金钟山卵翅蝗属一新种，即金钟山卵翅蝗Ｃａｒｙａｎｄａ－ｊｉｎｚｈｏｎｇｓｈａｎｅｎｓｉｓ，ｓｐ．ｎｏｖ．． 相似文献