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1.
通过苏云金杆菌H3- 1 1 1菌株摇瓶培养液对蓑蛾进行室内毒力测定 ,4 8h毒力回归方程为y=4 1 94 0 +3 31 85x ,r =0 95 31 ,LC5 0 =0 0 0 0 0 2 5 7,与标准品比较其生物效价为 4 86 2 93IU·mg- 1 ,有较高的毒效 ;同时经大田试验表明BtH3- 1 1 1菌株防治蓑蛾高峰期在药后 72~ 96h ,稀释 5 0 0~1 0 0 0倍的防效达 92 4 6 %~ 95 1 5 % ,超过化学农药DDVP的最高防效 (85 0 7% ) ,可替代化学农药用于蓑蛾的防治中  相似文献   

2.
在广西柳州市选择危害街道或庭院绿化树白玉兰(Michelia alba DC.)和火力楠(Michelia macclurei Dandy)的丽绵蚜(Formosaphis micheliae Takahashi),于危害期用40%氧化乐果乳油(原液,15倍液和500倍液)和80%敌敌畏乳油(原液)进行刮皮涂干防治试验.结果表明,40%氧化乐果乳油原液刮皮涂干防治效果达94%以上,来年该虫的复发率仅8.8%;40%氧化乐果乳油15倍稀释液防治效果可达到90%以上,来年该虫的复发率达87%.40%氧化乐果乳油500倍稀释液和80%敌敌畏乳油原液防治效果较差,仅为28%和25%.这种40%氧化乐果乳油刮皮涂干防治丽绵蚜方法,可减少化学药剂对环境的影响,而且方法简便,成本低,效果好,适宜在人为活动较频繁的公园、机关大院、校园、庭院白玉兰被害木推广使用.  相似文献   

3.
为了开发新型的红茶果蔬饮料,以不同产地的红茶样品、青萝卜、雪花梨和木瓜为原料,在不同条件下生产果蔬饮料,选用专业人员对果蔬汁进行打分评定.首先采用热回流装置和紫外分光光度法提取并测定不同红茶样品的咖啡碱含量,以含量最高的安化红茶为原料制作红茶咖啡碱原液,以口感最好的英德红茶为原料制作红茶提取液,佐以新鲜果蔬,采用正交试验方法以获取各种果蔬饮料的最佳生产工艺.结果表明,红茶青萝卜饮料的最佳配方为(除蔗糖为质量分数外,其余均为体积分数,下同):红茶咖啡碱原液5%,红茶提取液10%,青萝卜汁60%,蔗糖3.0%;红茶梨汁饮料的最佳配方为:红茶咖啡碱原液5%,红茶提取液10%,梨汁65%,蔗糖1.5%;红茶木瓜饮料的最佳配方为:红茶咖啡碱原液5%,红茶提取液10%,木瓜汁70%,蔗糖3.5%;红茶果蔬复合型饮料的最佳配方为:红茶咖啡碱原液5%,红茶提取液5%,青萝卜汁10%,梨汁30%,木瓜汁25%,蔗糖3.0%.  相似文献   

4.
以组培难生根的大花序桉(Eucalyptus cloeziana)和易生根尾巨桉继代苗为材料,用生物和化学显色方法鉴定大花序桉的内源生根抑制物质。结果表明:与尾巨桉相比,大花序桉继代苗提取液对绿豆和红豆的发芽无显著影响;大花序桉提取原液对绿豆插条发根率、发根量和根长均有明显的促进作用,尾巨桉GL9原液则有明显的抑制作用,差异达显著水平,提取液稀释1倍后无显著差异;两者提取液含黄酮类物质,不含烯醇结构酚类和皂甙,初步判断大花序桉组培生根的抑制物质可能为黄酮类物质。  相似文献   

5.
离子色谱法测定米糠中植酸含量   总被引:2,自引:0,他引:2  
采用微波消解技术将植酸转化为磷酸盐,然后用离子色谱法测定磷酸盐,从而获得米糠中植酸含量.实验中比较了米糠直接消解、提取液直接消解和提取液经阴离子交换处理消解的测定结果.离子色谱定量工作曲线方程为y=0.116 1x+0.650 9,相关系数为R2=0.998 0,测定结果相对标准偏差为0.68%,回收率为97.0%~102.3%,结果令人满意.  相似文献   

6.
生防菌NH-BS-2000对西瓜枯萎病原菌抑制作用的研究   总被引:5,自引:0,他引:5  
测定了生防菌NH BS 2000对西瓜枯萎病原菌的抑制作用.结果表明,培养温度对生防菌NH BS 2000的生长有显著影响,35℃培养的生防菌浓度比15℃培养的多54倍,它们对镰刀菌的抑制率分别为74.0%和63.2%,差异显著;浓度对生防菌抑制病原菌作用的影响不显著,生防菌液原液与1000倍稀释液对病原菌抑制率分别为62.0%和64.2%;用生防菌NH BS 2000处理病原菌8d后,抑制率均在62%以上,最高抑制率达80.6%,而且抑制作用的持续性强.说明NH BS 2000菌株具备作为枯萎病生防菌的良好优势.  相似文献   

7.
梧桐花粉主要变应原的分离纯化刘叶青 * , 崔玉敏 , 张秀萍 , 陈国豪(华东理工大学生物反应器工程国家重点实验室 ,生物工程系 ,上海 2 0 0 2 37)  摘要 :以离子交换和凝胶过滤层析对梧桐花粉变应原进行分离和纯化。采用生物素 -链霉亲和素酶联免疫吸附分析法 ( BSA- ELISA)测定其抗原活性 ,得到两个具高活性的单一变应原组分 PT13和 PT53 。经 SDS-聚丙烯酰胺凝胶电泳测得两者的相对分子质量分别为 2 0 ku和 1 8ku乙二胺羟丙基壳聚糖固定化天门冬酰胺酶的研究方 波 , 王任远 , 宋道云 , 周纪宁 , 江体乾 , 陈鸿雁(华东理…  相似文献   

8.
测定了马尾藻提取液的活性物质.研究提取液在食药用真菌营养生长中的作用.结果表明:在HPLC测定中,马尾藻提取液中含有GA3及α-NAA,质量浓度分别为0.68和1.21×10-4g/L,多糖的提取率为19.274%.在分别含有稀释1 200倍和800倍马尾藻提取液的糙皮侧耳、金针菇、羊肚菌PDA培养基中,长速显著高于对照,达12,9.80,12.18 mm/d.  相似文献   

9.
为有效防治芳香木蠹蛾,采用树干注射不同浓度40%氧化乐果乳油稀释液的方法,以不同树龄的稠李为实验对象,对芳香木蠹蛾1~3龄幼虫进行防治试验。经相互比较实验结果而知,在一定范围内(以对植株不产生伤害为基准),对于近似周径的稠李而言,浓度越大,防治效果越好;而同一浓度,相同的注射量,对于不同树龄而言,则周径越小,防治效果越好。  相似文献   

10.
为有效防治芳香木蠹蛾,采用树干注射不同浓度40%氧化乐果乳油稀释液的方法,以不同树龄的稠李为实验对象,对芳香木蠹蛾1~3龄幼虫进行防治试验.经相互比较实验结果而知,在一定范围内(以对植株不产生伤害为基准),对于近似周径的稠李而言,浓度越大,防治效果越好;而同一浓度,相同的注射量,对于不同树龄而言,则周径越小,防治效果越好.  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.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  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 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   

15.
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   

16.
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   

17.
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   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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