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1.
采用乙醇-无机盐双水相技术,研究了从国产新楝果核中提取印楝素的工艺.通过单因素实验和正交实验探讨了无机盐的质量浓度、提取时间、料液比对印楝素提取率的影响.实验结果表明:正交提取、双水相体系纯化印楝素的最佳条件是:无机盐浓度为0.62g/mL,提取时间为1.5h,料液比为1∶10(g∶mL),此时印楝素的提取率为1.23%.  相似文献   

2.
对印楝油进行皂化得到了印楝油的总脂肪酸,将总脂肪酸甲酯化得到总脂肪酸甲酯,用GC-MS联用仪测定其中所含高级脂肪酸.结果表明印楝油中含有油酸,亚油酸,棕榈酸,硬脂酸,花生酸等十种高级脂肪酸成分.  相似文献   

3.
通过改变印楝组织培养基中硝态氮与铵态氮物质的量比,并与培养物的生物量、可溶性蛋白含量、印楝素、柠檬苦素含量相关联,探讨了MS培养基中氮素对印楝愈伤组织和悬浮细胞培养的影响.实验结果表明:在印楝的愈伤组织培养过程中,当硝态氮与铵态氮物质的量比为4∶1时,生物量、可溶性蛋白含量、印楝素以及柠檬苦素含量均达到最大积累量;在悬浮细胞培养的过程中,当硝态氮与铵态氮物质的量比为3∶1时,可溶性蛋白含量、印楝素以及柠檬苦素含量达到最高,而在2∶1时生物量达到最大.因此,印楝组织培养的不同阶段应该采用不同形式氮素比例的培养基,只有这样才能获得最佳的目标培养物.  相似文献   

4.
为了探究印楝细胞培养物控制害虫的效果,本文通过诱导幼叶、继代培养获得印楝的松散型愈伤组织,再经振荡培养获得悬浮细胞培养物;然后采用二氯甲烷溶剂浸提愈伤组织、悬浮培养物及悬浮培养细胞,制备相应的浸提液;用二氯甲烷分别将这些浸提液稀释成含0.003%印楝素A的控虫工作液,用其分别处理黄粉虫幼虫,在12d内,考察其控虫效果.结果表明:3种浸提液的致死效应明显高于阴性对照,其中,第9天的最大致死率达到20%,但它们要明显低于0.003%印楝素乳油农药的处理;3种浸提液对幼虫的虫体质量、拒食和趋避作用等方面效果较好,均达到印楝乳油杀虫剂的控虫水平.印楝细胞培养物经一步浸提后,直接用于控虫制剂的生产,可以节约分离、提纯印楝素等生产性成本.  相似文献   

5.
印楝植物农药的研究进展   总被引:6,自引:0,他引:6  
印楝中的有效成分印楝素是一种比较完美的植物源杀虫剂.本文叙述了国内外有关印楝研究的现状、有效成分的提取方法、印楝素及其制剂的稳定性控制、制剂的主要成分以及印楝杀虫剂对昆虫的作用途径和机制,并对印楝杀虫剂的发展趋势作了展望。  相似文献   

6.
微波萃取印楝叶中的印楝素研究   总被引:9,自引:0,他引:9  
 应用经改造的家用微波炉为主要设备,对微波萃取印楝干叶中印楝素作了L9(34)正交实验.考察了4个因素:微波辐射时间、微波功率、溶剂用量、洗涤滤饼的溶剂量对提取率、溶剂回收率、印楝素总质量分数3个指标的影响.实验结果表明:每4.5g印楝干叶,微波萃取印楝素的最佳组合为辐射时间80s,微波功率365W,溶剂用量100mL,洗涤滤饼的溶剂量10mL.  相似文献   

7.
印楝素是目前世界上公认的活性最强的拒食剂,被认为是最适合于商品化开发的植物源杀虫剂。通过对印楝种子消毒时间、不同有机溶剂萃取方法、萃取液旋转蒸发温度、时间等条件进行了摸索,最终通过液质联用技术从印楝种仁内生菌发酵液、菌丝体提取液中均检测到印楝素A,为印楝素制剂的开发提供了一条可供参考的途径。  相似文献   

8.
本文广泛介绍印楝的用途,重点介绍了印楝作为杀虫剂和在医药方面的作用,并阐明印楝在城市绿化中的作用。  相似文献   

9.
采用木本植物材料——印楝,通过组织培养建立快繁体系,然后对其进行冷驯化处理,并分析检测印楝植物体内抗冻蛋白.主要结果如下:①冷驯化处理后印楝的总蛋白一些表现为量的增加同时会有新的蛋白产生.但脱驯化或处理时间过长时,抗冻蛋白在量的表达上会有逐渐减少或消失的现象.②在对印楝的冷驯化中,发现不同的温度处理后蛋白稳定存在的时间不同.抗冻蛋白出现的最早时期为5℃处理2周左右,印楝能耐受的稳定最低温为5℃,所持续的最长时间约为20d.在0℃低温处理后,虽然在处理初期(0~15d)也有抗冻蛋白的产生,但随处理时间的延长,这种差异逐渐减少,在处理30d时完全消失.③得到了分离纯化的抗冻蛋白,其相对分子质量约为3.6×104.  相似文献   

10.
印楝、印楝杀虫剂与生态环境   总被引:9,自引:0,他引:9  
印楝是一种耐旱速生的亚热带或热带树种,是世界公认的优秀生物农药。它不易受病虫危害,是防风固沙、改良水土和治理生态环境的优良树木。印楝杀虫剂无残留,可减缓害虫的抗药性,对脊椎动物的毒性极低,对鸟类、鱼类、蜜蜂、蚯蚓等非靶标生物安全,对捕食性蜘蛛、捕食性蟋蟀、捕食性甲虫、寄生蜂等害虫天敌无明显的毒性,在环境中无残留,是用于蔬菜、果树、茶叶等作物的理想农药。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

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