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Search Results: 1 - 10 of 789957 matches for " 李春丽a "
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四(2'-己基)-Δ7,7'-双环戊[1,2-b:4,3-b']并二噻吩的合成、表征及晶体结构
王华a,赵文玲a,史建武a,王治华b,a
河南大学学报(自然科学版) , 2012,
Abstract: 以2-己基噻吩为起始原料,经溴代、溴迁移、氯化铜氧化偶联、羰基化、成烯偶联制备了四(2'-己基)-Δ7,7'-双环戊[1,2-b:4,3-b']并二噻吩(1),总产率为18.1%.产物通过了核磁共振、高分辨质谱、红外光谱的表征.X-射线单晶衍射分析确定了该化合物分子的晶体属于三斜晶系,P-1空间群,晶胞尺寸:a=0.8464(5)nm,b=0.9131(5)nm,c=1.3963(9)nm,α=89.873(11)°,β=84.604(10)°,γ=62.7
气相色谱法检测水产品中拟除虫菊酯类农药的基质效应研究

- , 2018, DOI: 10.13982/j.mfst.1673-9078.2018.04.040
Abstract: 本研究建立了水产品中9种拟除虫菊酯类农药残留量的快速检测方法,研究了草鱼、鲫鱼、鲢鱼、罗非鱼和对虾对9种拟除虫菊酯类农药的基质效应,并分析了基质种类、基质浓度和目标分析物浓度对基质效应的影响。结果表明,该方法下9种拟除虫菊酯类农药在5.0~750 ng/mL(七氟菊酯为2.5~750 ng/mL,氯菊酯为10~750 ng/mL)浓度范围内线性关系良好,相关系数在0.9996~0.9999。加标浓度为5.0、50和100 μg/kg水平下,平均加标回收率在80.1±2.95%~116±2.45%之间,日内精密度和日间精密度分别为0.272%~10.7%和0.164%~12.8%。5种水产品对9种菊酯类农药均存在不同程度的基质效应,其基质效应在0.906~2.45之间,基质效应随基质浓度增加而增强。此外农药浓度对其基质效应也有较大影响,随农药浓度的增加基质效应逐渐减弱。因此在检测水产品中拟除虫菊酯类农药时应采用基质加标的方法减弱或消除基质效应,确保定量检测结果的准确性。
A rapid method was developed for the detection of 9 pyrethroid pesticides in aquatic products in this study. The matrix effects of Ctenopharyngodon idellus, Carassius auratus, Hypophthalmichthys molitrix, Oreochromis spp and Penaeus orientalis on 9 pyrethroid pesticides were studied, and the effects of matrix types, pesticids concentration and matrix concentration on the matrix effects were analyzed. The results showed that the 9 pyrethroid pesticides had a good linear relationship with the concentration in range of 5.0~750 ng/mL (tefluthrin of 2.5~750 ng/mL, pemethrin of 10~750 ng/mL) with the correlation coefficients of 0.9996~0.9999. The average recoveries of standard addition were 80.1±2.95%~116±2.45 % with the concentration of 5.0, 50 and 100 μg/kg, and the intra-day and inter-day precision were 0.272%~10.7 % and 0.164%~12.8 %, respectively. Different five kinds of aquatic products had different degree of matrix effects on 9 pyrethroids, and the matrix effects were in the range of 0.906~2.45. The matrix effects increased with the increase of matrix concentrations, and the Oreochromis spp, Hypophthalmichthys molitrix and Penaeus orientalis improved the matrix effects. In addition, the concentrations of target analysis had a significant influence on its matrix effect, and the matrix effect decreased with the increase of pesticide concentrations. Therefore, the matrix additive method should be used to reduce or eliminate the matrix effect to ensure the accuracy of quantitative result.
人β防御素3和植物des-pglu1-brazzein融合蛋白的纯化、活性分析及其乳糖诱导表达条件优化
,阮晖
农业生物技术学报 , 2008,
Abstract: ?对乳糖诱导工程菌株bl-pet-hbd3-bra表达的人β防御素3和植物des-pglu1-brazzein融合蛋白进行了纯化和活性分析。并对工程菌株的乳糖诱导表达条件进行了优化。对目的蛋白的活性分析表明,hbd3-bra融合蛋白有一定的甜味,但是杀菌活性很弱,经凝血酶切割后,重组hbd3有明显的抑菌活性,des-pglu1-brazzein的甜度大约为蔗糖甜度的600倍。乳糖浓度、诱导时间和诱导温度对菌株生长和目的蛋白表达的试验结果显示:高浓度乳糖对菌株生长有抑制作用(p<0.01),对目的蛋白的表达无显著影响(p>0.05);时间延长对于菌株生长有利(p<0.01),对目的蛋白的表达无显著影响(p>0.05);温度对菌株生长和目的蛋白的表达均有显著影响(p<0.01)。进一步的研究表明,菌株在30℃-32℃生长,在30℃诱导最优,乳糖和iptg的诱导结果无显著差异(p>0.05)。
一种复合型成膜剂的成膜性能测定及其对生防菌抑菌活性的影响
,
农药学学报 , 2009,
Abstract: 制备了不同比例的聚乙烯醇-羧甲基纤维素钠-钠基膨润土共混膜。结果表明:以质量浓度2%的聚乙烯醇(pva)、1%的羧甲基纤维素钠(scmc)及0.3%的钠基膨润土(na-b)制得pva-scmc-na-b共混膜,其成膜时间为7min、粘度为480mpa·s,对棉种的包衣均匀度为98%,包衣脱落率为0.15%,并具有良好的水溶性和吸水溶胀性,而且共混膜对微生物的生长及抑菌活性、种子发芽率几乎无影响,可为新型绿色生物种衣剂的应用及推广提供参考。
物理课程融入STEM教育理念的研究与实践
,
- , 2017,
Abstract:
无花果果实发育过程中ABA和乙烯含量与果实成熟的关系
Relationship between ABA and ethylene content and fruit ripening during fig fruit development

,沈元月
- , 2016,
Abstract: 为研究无花果果实发育过程中ABA和乙烯含量与果实成熟的关系,以玛斯义陶芬(Masui dauphine)无花果果实为试材,对果实发育过程中呼吸速率和乙烯释放量及可溶性糖、淀粉和ABA含量进行了研究。结果表明:无花果果实发育分3个时期,第1个快速生长期(时期Ⅰ)、缓慢生长期(时期Ⅱ)和第2个快速生长期(时期Ⅲ),在缓慢生长期和第2个快速生长期之间为果实发育的转折期“始熟期”。始熟期后果实淀粉分解,大量积累葡萄糖和果糖,果实快速进入成熟期。无花果果实发育过程中ABA含量整体呈下降趋势,乙烯释放量随着果实发育逐渐增加,在始熟期和呼吸速率同步出现一个高峰。结果表明无花果果实是呼吸跃变型果实,乙烯诱导果实发生一系列生理生化变化,促使无花果果实成熟。
To study the relationship between ABA and ethylene content and fruit ripening during the development of fig fruit,fig (Ficus carica L.) cultivar ‘Masui Dauphine’ was used in this study.The changes of respiratory rate,soluble sugar content,starch content,ABA level and ethylene production level were examined.The results showed that:The development of fig fruit was comprised of three phases,phase Ⅰ (the first rapid growth stage),phase Ⅱ (the lag phase of growth),and phase Ⅲ (the second rapid growth stage).The transition from phase Ⅱ to phase Ⅲ was the onset of ripening.After the onset of ripening,starch content of fig fruit was decreased,but a large amount of glucose and fructose were accumulated,and the fruit matured quickly.There was an decrease in ABA content during ripening of fig fruits.But there was an increase in ethylene production during fig fruits ripening,and during the onset of ripening a respiratory climacteric rise was concomitant with a sudden burst of endogenous ethylene production.These results suggested that fig fruit is a typical climacteric fruit.Ethylene initiated a chain of metabolic and physiological events which lead to fig fruit ripening.
有机肥施用对植胶土壤影响的研究
,
热带农业科学 , 2010,
Abstract: 综述有机肥对提高土壤肥力、改善土壤理化性状、提高肥料利用率和作物抗病性等方面的重要作用,阐明有机肥在橡胶上的应用前景。提出综合利用热区有机肥的措施,变废为宝,促进橡胶产业可持续发展。
应用分子标记差异性预测作物杂种优势的研究进展 The Progress in Prediction of Plant Heterosis Using Molecular Marker
LI,Chun-Li
遗传 , 1997,
Abstract: 应用分子标记差异性预测作物杂种优势的研究进展李春丽①(中国水稻研究所生物工程系,杭州310006)TheProgressinPredictionofPlantHeterosisUsingMolecularMarkerLiChunli②(Departm...
Design of Intellective Node of Ozonizers Based on CAN-Bus
臭氧发生器基于CAN 总线的智能节点的设计

,钟细军
计算机系统应用 , 2009,
Abstract: 针对多台臭氧发生器同时监控下对智能节点设计的需求,介绍了基于CAN 总线的臭氧发生器智能节点的总体设计、硬件设计和部分软件设计。实际运行表明,该智能节点很好的满足了需求,且运行可靠,硬件设计简单,有利于更多功能的扩展。
罗山国家级自然保护区森林植被资源监测与分析
Analysis and Monitoring of Forest Vegetation Resource in Luoshan National Nature Reserve
 [PDF]

, 仇智虎, 秦伟, 曹兵, 刘超,
World Journal of Forestry (WJF) , 2014, DOI: 10.12677/WJF.2014.34011
Abstract:
根据罗山保护区的典型地带性特点和森林植被资源特点,按照长期定位监测的要求,在保护区设置用于长期定位监测植被变化情况的样地,对罗山的植被资源定位监测,系统分析其植被多样性,为罗山自然保护区科学管理与可持续发展提供依据。结果表明:以草地和灌木地为主的山体共有木本植物32种,草本植物168种。小罗山以草本和灌木植物为主,平均高度分别为16.54 cm和36.69 cm;大罗山植被分布复杂、种类多,植被以草地和灌木地为主的山体物种丰富度在0.007~0.009这之间。罗山大多数植物种多度小于20%,木本灌木的多度大于50%,草本植物种的频度小于40%。调查的几条路线中,物种丰富度指数差异较小。
According to the typical zonality and forest vegetation characteristics of Luoshan nature reserve, and long-term located monitoring requirement, we set up sample plots in Luoshan nature reserve for long-term located monitoring of forest vegetation to analyze its dynamic changes and biodiversity that will provide reference for scientific management and sustainable development in Luoshan nature reserve. The result shows that there are 168 herbaceous plants and 32 woody plants for all grassland and shrub plots. The small Luoshan only has herbaceous plants and shrubs, and their average height is 16.54 cm and 36.69 cm respectively. The plants in big Luoshan are more diverse and complex, and species richness of grassland and shrub plots is between 0.007~0.009. The abundances for different plants in Luoshan are less than 20%; the abundances for woody plants are greater than 50%, while frequentness for herbaceous plants is less than 40%. There is no big difference in species richness index of the plots in Luoshan.
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