期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
两种穗型粳稻穗内粒间直链淀粉含量变异与粒位分布特征 被引量:16
1
作者 朱海江 程方民 +3 位作者 王丰 钟连进 赵宁春 刘正辉 《中国水稻科学》 CAS CSCD 北大核心 2004年第4期321-325,共5页
以 6个直穗型和 4个弯穗型粳稻品种为材料 ,对两者在相同栽培条件下的穗内粒间直链淀粉含量变异及其频数分布、粒位特征进行了比较分析。结果表明 :水稻穗型虽然与品种间的直链淀粉含量高低无直接关系 ,但对其穗内不同籽粒间的直链淀粉... 以 6个直穗型和 4个弯穗型粳稻品种为材料 ,对两者在相同栽培条件下的穗内粒间直链淀粉含量变异及其频数分布、粒位特征进行了比较分析。结果表明 :水稻穗型虽然与品种间的直链淀粉含量高低无直接关系 ,但对其穗内不同籽粒间的直链淀粉含量差异存在着较大的影响 ;直穗型粳稻品种单一稻穗内直链淀粉含量的粒间差异明显大于弯穗型品种 ,其直链淀粉含量的粒间变异系数与离散程度均高于后者 ;同一稻穗内不同籽粒间的直链淀粉含量变化与其相应的粒位有关 ,两种穗型粳稻品种均表现为穗顶部籽粒的直链淀粉含量相对较高、穗基部籽粒的直链淀粉含量相对较低这一基本趋势。但与弯穗型粳稻品种相比 ,直穗型粳稻品种大量低直链淀粉含量籽粒产生的部位是在其稻穗的中部 ,而不仅仅局限在稻穗基部的 3个枝梗上。 展开更多
关键词 穗型 粳稻 穗内间变异 直链淀粉含量 粒位分布
下载PDF
Use of Solid SMEDDS in Delivery of Carvedilol 被引量:1
2
作者 魏兰兰 孙佩男 +3 位作者 田蕾 唐歆 姚婷婷 潘卫三 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第4期223-227,共5页
Aim A new solid SMEDDS (self-microemulsifying drug delivery system) capsule has been developed to increase the solubility and dissolution rate. Methods The solubilities of carvedilol in various bases were investigated... Aim A new solid SMEDDS (self-microemulsifying drug delivery system) capsule has been developed to increase the solubility and dissolution rate. Methods The solubilities of carvedilol in various bases were investigated. Ternary phase diagrams were used to evaluate the self-emulsification and self-microemulsfication domains. The particle size distribution and ζ-potential were determined. The mean diameter of the three formulae decreased with an increase of Lutrol F68. Results The in vitro dissolution rate of ... 展开更多
关键词 self-microemulsification CARVEDILOL particle size distribution ζ-potential DISSOLUTION
下载PDF
Effect of Placements (horizontal with vertical) on Gas-solid Flow and Particle Impact Erosion in Gate Valve 被引量:2
3
作者 LIN Zhe ZHU Linhang +2 位作者 CUI Baoling LI Yi RUAN Xiaodong 《Journal of Thermal Science》 SCIE EI CAS CSCD 2014年第6期558-563,共6页
Gate valve has various placements in the practical usages.Due to the effect of gravity,particle trajectories and erosions are distinct between placements.Thus in this study,gas-solid flow properties and erosion in gat... Gate valve has various placements in the practical usages.Due to the effect of gravity,particle trajectories and erosions are distinct between placements.Thus in this study,gas-solid flow properties and erosion in gate valve for horizontal placement and vertical placement are discussed and compared by using Euler-Lagrange simulation method.The structure of a gate valve and a simplified structure are investigated.The simulation procedure is validated in our published paper by comparing with the experiment data of a pipe and an elbow.The results show that for all investigated open degrees and Stokes numbers(St),there are little difference of gas flow properties and flow coefficients between two placements.It is also found that the trajectories of particles for two placements are mostly identical when St << 1,making the erosion independent of placement.With the increase of St,the distinction of trajectories between placements becomes more obvious,leading to an increasing difference of the erosion distributions.Besides,the total erosion ratio of surface T for horizontal placement is two orders of magnitudes larger than that for vertical placement when the particle diameter is 250 μm. 展开更多
关键词 gate valve PLACEMENT flow properties EROSION
原文传递
Improved Algorithm for Distributed Localization in Wireless Sensor Networks 被引量:3
4
作者 钟幼平 匡兴红 黄佩伟 《Journal of Shanghai Jiaotong university(Science)》 EI 2010年第1期64-69,共6页
Many sensor network applications require location awareness,but it is often too expensive to equip a global positioning system(GPS) receiver for each network node.Hence,localization schemes for sensor networks typical... Many sensor network applications require location awareness,but it is often too expensive to equip a global positioning system(GPS) receiver for each network node.Hence,localization schemes for sensor networks typically use a small number of seed nodes that know their locations and protocols whereby other nodes estimate their locations from the messages they receive.For the inherent shortcomings of general particle filter(the sequential Monte Carlo method) this paper introduces particle swarm optimization and weighted centroid algorithm to optimize it.Based on improvement a distributed localization algorithm named WC-IPF(weighted centroid algorithm improved particle filter) has been proposed for localization.In this localization scheme the initial estimate position can be acquired by weighted centroid algorithm.Then the accurate position can be gotten via improved particle filter recursively.The extend simulation results show that the proposed algorithm is efficient for most condition. 展开更多
关键词 wireless sensor network node localization particle filter particle swarm optimization weighted centroid algorithm
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部