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71.
对山苍子果实产量及油质的影响的因素有很多。本文主要就产地条件对其影响进行了调查.其结果表明:立地条件直接影响到山苍子果实的产量.而对其油质的影响不很显著。这对山苍子的生产经营而言,有一定的参考价值。  相似文献   
72.
减速箱橡胶油封漏油是一个尚未解决的一个棘手问题 .从摩擦学的角度分析 ,漏油的原因主要是油封与转轴接触部位不符合摩擦学的要求 ,造成此处的摩擦系数过高 ,油封磨损过快 .介绍了几种降低橡胶油封与转轴之间摩擦系数的方法  相似文献   
73.
八角茴香油化学成份的研究   总被引:1,自引:0,他引:1  
八角茴香(Illicium verum Hook.f.)属八角科,是一种芳香植物,其果实和鲜枝叶可用水蒸汽蒸馏提取八角茴香油。本文用GC/MS联用仪鉴定了果油和枝叶油的组分,用GC测定了含量,并对检验方法提出了建议。  相似文献   
74.
浅谈沥青路面的病害与防治   总被引:1,自引:0,他引:1  
本文作者对沥青路面的病害成因作了一般性分析及论述,并提出了几项防治措施。  相似文献   
75.
波纹杂毛虫综合防治试验   总被引:6,自引:1,他引:6  
波纹杂毛虫幼虫 [Cyclophragmaundans (walker) ]是马尾松林又一害虫 ,用 2 5 %溴氰菊酯 2 5 0 0倍液、4 0 %氧化乐果80 0倍液、80 %敌敌畏乳油 15 0 0倍液、5 0 %甲胺磷乳油 10 0 0倍液 ,防治效果可达 92 %以上。用 2 5 %溴氰菊酯乳油加白僵菌纯孢子油剂 1∶80采取超轻型飞机超低容量喷雾 ,防治效果可达 95 %以上。在气象条件适宜情况下 (地面温度呈逆增时 ) ,在凌晨施放林丹烟剂加 2ml的 2 5 %敌敌畏乳油 ,用量 15kg·hm-2 ,对 2~ 4龄幼虫防治效果可达 95 %以上。  相似文献   
76.
李占君  郭兴  徐宜彬  杨逢建 《林业科技》2020,45(3):23-25,62
采用不同提取方式对塔拉籽油提取率、理化指标、脂肪酸构成进行测定的结果表明:在索氏、超声、超临界3种提取方式中,超临界在塔拉籽油的提取率和脱酸方面表现最好,相关理化指标的表现也较好;塔拉籽油脂含有棕榈酸、棕榈油酸、硬脂酸、油酸、亚油酸、花生酸、亚麻酸、二十二碳酸等8种脂肪酸,不同提取方式对脂肪酸构成及含量无明显影响,超临界为塔拉籽油最优提取方式。  相似文献   
77.
以阿拉伯胶和明胶为壁材的凝聚法生产茶油微胶囊的工艺过程及条件如下5%阿拉伯胶和5%明胶与一定量油茶籽油在60℃下乳化1min,在pH4.4下凝聚0.5h,10℃下固化1h,经离心和真空干燥即可.该法制备的微胶囊,有较高的含油率和包埋率.其粒径与凝聚时的搅拌速度密切相关,但其水溶性较差.  相似文献   
78.
The value of eucalyptus oil for medicinal purposes is based largely on its cineole content. The prime commercial species for cineole production in Australia is Eucalyptus polybractea (blue mallee). Despite the long history of blue mallee harvesting in Australia, there has been little research on the establishment of plantations of the species or on the efficacy of short-rotation coppice cultivation with respect to the consistency of oil yield and quality from rotation to rotation. This study aims to assess if subsequent coppice oil traits reflect sapling traits and if the coppice oil traits under short-rotation cultivation are consistent from one rotation to the next. A trial plantation was established in a key eucalyptus oil harvesting district in Victoria. Firstly, the oil-related traits of 20 saplings harvested 3.5 years after planting were compared with those of their subsequent coppice harvested after 12 months regrowth. Despite the expected differences in total biomass, the oil-related traits of blue mallee saplings were mostly well reflected in their subsequent coppice. Total above ground biomass and foliar oil concentration were significantly related between saplings and coppice, and cineole proportion showed a Pearson's correlation of 0.93 between harvests. Nevertheless, the mean foliar oil concentration in the coppice was 148 mg g−1 dw compared with 107 in the saplings, and the coppice foliage, on average, showed significantly reduced cineole with a mean of 87% in the saplings (maximum of 95.6%) compared to a mean of only 80% in the coppice (maximum of 87.0%). Secondly, the oil traits of 20 coppice plants from one 12-month harvest rotation to the next were compared. Again, total above ground biomass, foliar oil concentration and cineole proportion were significantly related between the harvests, with cineole proportion having a Pearson's correlation of 0.90 between rotations. The coppice between rotations were remarkably consistent in terms of biomass and oil traits and indeed mean coppice cineole yields were 28.6 and 29.7 g in rotations 1 and 2, respectively. The results support the screening of key oil-related traits in saplings for the selection of elite genotypes for plantations, and the use of short-rotation cultivation of the plantations for continued oil harvesting. Furthermore, no relationship was observed between biomass and oil concentration in the blue mallee saplings or coppice, suggesting selection gains in a given key oil trait will not result in losses in another.  相似文献   
79.
Two new amino acid-type amphoteric surfactants — disodiumN-(2-fatty acyl amino) ethyliminodiacetate and disodiumN-(2-fatty acyl amino) ethyl-N,N-bis[3-(2-hydroxy) propylsulfonate] amine — were synthesized using tall oil fatty acids as the raw material. Suitable processing conditions for synthesizing the intermediates and final products were probed. In addition, the chemical structures of the intermediates and the final products were identified by infrared spectroscopy, hydrogen nuclear magnetic resonance spectroscopy, and elemental analysis.  相似文献   
80.
This is the first article to report the evaluation of a natural product used as an antisilverfish agent. Silverfish (Lepisma saccharina), primitive wingless insects, feed on a variety of materials, including paper, cotton, starch, and cereals. They can be a problem in libraries and other places where books, documents, and papers are stored. In this pilot study, the essential oil from leaves of Cryptomeria japonica was investigated to test its properties as a silverfish repellent and insecticide. The results from a repellency bioassay show that the essential oil significantly repelled silverfish. The repellent activity was 80% at a dosage of 0.01 mg/cm3. When silverfish were exposed to a concentration of 0.16 mg/cm3 of essential oil, they were killed within 10h. The chemical composition of essential oil, the emissions from a test chamber, and the residue left on filter papers previously soaked with the essential oil in a chamber were analyzed by gas chromatography-mass spectrometry. The components of the essential oil were found to be: elemol (18.22%), 16-kaurene (11.63%), 3-carene (9.66%), sabinene (9.37%), 4-terpineol (9.06%), β-eudesmol (5.70%), α-pinene (5.62%), and limonene (5.26%). Only some constituents of the essential oil compounds collected by solid-phase microextraction were found to be emitted in the test chamber. The main constituents were: 3-carene (21.03%), p-cymene (10.95%), limonene (9.49%), β-myrcene (9.39%), γ-terpinene (9.10%), α-terpinene (8.57%), and 4-terpineol (7.97%).  相似文献   
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