The current and residual value of superphosphate for lupins grown in rotation with oats and wheat on a deep sandy soil

In a field experiment on a deep pale-yellow sand in a 600 mm per annum rainfall Mediterranean environment of south-western Australia, six levels of phosphorus (P) as superphosphate (O up to 546 kg P ha^–1) were applied once only, to the soil surface, before sowing lupins (Lupinus angustifolius). The lupins were grown in a continuous arable cropping rotation with, in successive years, oats (Avena sativa), wheat (Triticum aestivum), lupins. Five such rotations were started in the experiment from 1985 to 1989. The experiment continued until the end of 1990.The relationship between lupin seed (grain) yields and the level of P applied was measured in the year of P application for five successive years (1985 to 1989). The relationship had the same general form but it varied between years, largely due to different maximum yields (yield plateaux) in each year.The residual value of superphosphate applied three years previously was measured for lupins on two occasions (1988 and 1989) relative to superphosphate applied in the current year. The residual values was different in the two years. The superphosphate applied three years previously was about 30% as effective as freshly applied superphosphate in 1988, and 12% as effective in 1989.At each harvest, the relationship between grain yield and the P concentration in the grain differed for different species. However, for each species at each harvest, the relationship was similar regardless of when the P was applied in the previous years. Thus each species had the same internal efficiency of P use curve, and yields varied only with P concentration in tissue.Bicarbonate-extractable soil P was determined on soil samples taken in mid-July of 1989 and 1990. These soil test values were related to grain yields at harvest. The relationship between yield and soil test values had the same general form but varied for different species within years and for each species between years. It also varied for each species within years depending on the year the P was applied.     

Preparation of core–shell type nanoparticles of diblock copolymers of poly(L‐lactide)/poly(ethylene glycol) and their characterization in vitro

Core–shell type nanoparticles of poly(L ‐lactide)/poly(ethylene glycol) (LE) diblock copolymer were prepared by a dialysis technique. Their size was confirmed as 40–70 nm using photon correlation spectroscopy. The ¹H‐NMR analysis confirmed the formation of core–shell type nanoparticles and drug loading. The particle size, drug loading, and drug release rate of the LE nanoparticles were slightly changed by the initial solvents that were used. The drug release behavior of LE core–shell type nanoparticles showed an initial burst during the first 12 h and then a sustained release until 100 h. The degradation behavior of LE block copolymer nanoparticles was divided into three phases: the initial rapid degradation phase, the stationary phase, and the rapid degradation phase until complete degradation. It was suggested that lidocaine release kinetics were predominantly governed by the diffusion mechanism in the initial burst phase and after that by both of the diffusion and degradation mechanisms. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2625–2634, 2002     

磷系水质稳定剂的合成和应用

介绍了国内外磷系水质稳定剂的现状和发展，重点讨论了作为水质稳定剂的聚磷酸钠、有机多元膦酸、膦羧酸以及磷酸酯的合成和应用。     

有机EL的稳定性和寿命

介绍了有机ＥＬ在稳定性及寿命方面的最新研究动态，着重描述了器件功能层组合的相互接触、阴极、空穴传输层玻璃化温度和驱动条件等对有机ＥＬ稳定性和寿命的影响。     

光电微量氧分析仪的改进

简要介绍光电微量氧分析仪的改进。通过仪表几个重要特性的试验数据，概述黄磷反应室三种结构对氧与黄磷反应的影响，并应其反应机理作了理论分析。     

光度法测定金属表面处理溶液中的磷

采用光度法直接测定金属磷酸盐处理溶液中的磷，磷量在0～50ug／50mL内符合比耳定律。此法特点快速、简便、显色稳定性好、选择性强，回收率为98．00％～102．00％。     

小型密闭压力容器测试系统重复性的研究

小型密闭压力容器测试（MCPVT）法是安全工程领域中近几年发展起来的、评价有机过氧化物及自反应物质受热分解反应激烈程度的新方法。pmax是MCPVT方法中用来表征自反应物质受热分解反应激烈程度的物理量之一。文中通过大量实验，研究了样品容器容积V、升温速率R及样品质量M对pmax重复性误差的影响，研究了一系列典型的有机过氧化物和自反应物质在标准实验条件下pmax重复性误差。结果表明，小型密闭压力容器测试系统重复性好，测试结果可靠，从而为MCPVT法最终成为国际上评价自反应物质受热分解反应激烈程度标准方法奠定了基础。     

分光光度法测定黄磷尾气中总磷

实验研究了溴化硝酸吸收－分光光度法测定黄磷尾气中总磷含量的方法，总磷回收≥97%,方法检测限可达0.2μg/mL.     

用于铜的化学机械抛光液的研究

文中介绍了一种以碱性抛光液对铜进行全局平面化的方法 ,讨论了以 Si O2 水溶胶为磨料的抛光液在Cu-CMP过程中的化学 (络合 )作用及反应机理 ,并给出了抛光液的配比及上机实验结果。结果表明 :该抛光液用于对带有阻挡层和介质层的铜抛光 ,达到了对铜层的高去除速率和高选择比 ,取得了较好的全局平面化效果     

Hysys软件在分析精丙烯硫化物来源中的应用

气体分馏装置原料液化石油气 (LPG)中有机硫化物形态复杂 ,考察分析工业装置精丙烯硫化物含量变化难度大。利用Hysys模拟 ,分析判断LPG中小分子有机硫化物在气体分馏产品的分布并提出了控制措施。考虑操作条件对精丙烯硫含量的影响 ,并对工业装置精丙烯总硫超标原因进行了分析。