室温燐光猝灭法测定种子水分含量的研究——Ⅰ.作物种子中水分含量与 RTP 的相关性

本文基于作物种子中的水分能够猝灭种子本身的室温燐光强度,研究了干燥温度及干燥时间对燐光强度的影响。五种作物种子的实验结果表明,种子中的水分含量在一定范围内与RTP强度呈线性关系,其相关系数接近于-1。     

绿豆胰蛋白酶抑制剂片段及其类似物的合成

绿豆胰蛋白酶抑制剂的Lys活性碎片由两条分别含有26及9个氯基酸残基的多肽链通过两对分子间二硫键连接而成。用DTT还原能拆分两链,其中长链含6个半胱氨酸,在空气中氧化后能恢复25％原Lys碎片活力。本文报道了此长链的化学合成和二硫键重组。合成产物的氯基酸组成与文献报道的一致。但活性明显低于天然产物。为此对绿豆抑制剂的部分序列重新进行测定,结果表明原P_2′位的Lys应为Ile按新测定序列,从长链26肽的N端和C端各去掉两个残基合成一个22肽,此22肽的活性与天然的26肽相当。此外还合成了此22肽的类似物,其活性中心的Lys残基由Ala取代,产物对胰蛋白酶和弹性蛋白酶都无抑制活力。     

A New Triterpenoid Spaonin Isolated from the Seeds of Aesculus assamica Griff

The Aesculus genus consists of about thirty species distributed in Asia, Europe andAmerica. There are sixteen species distributed in China, and most of them are used asherbal medicines for the treatment of distention and pain in the chest and abdomen. Anu…     

聚硅氧烷/甲基丙烯酸甲酯核壳结构复合粒子的制备

聚硅氧烷/甲基丙烯酸甲酯核壳结构复合粒子的制备;种子乳液聚合;核壳结构     

核／壳结构聚丙烯酸酯塑料增韧剂的制备与结构控制

核／壳结构聚丙烯酸酯塑料增韧剂的制备与结构控制张会轩戴英杨海东＊冯之榴（吉林工学院化工系长春１３００１２）（中国科学院长春应用化学研究所１３００２２）关键词聚丙烯酸酯，增韧剂，制备，种子乳液聚合１９９６－０８－２８收稿，１９９７－０１－０６修回国家自...     

两步溶胀法合成奎宁印迹聚合物及性能研究

以超声合成的聚苯乙烯乳液为种子,奎宁为模板,通过两步溶胀和悬浮聚合的分子印迹技术,制备得到球形分子印迹聚合物.通过扫描电镜观察聚合物粒子形貌,测量粒径范围为50～80μm.此聚合物对模板分子具有良好的再识别能力,最大饱和净吸附量可达到61.2 μmol/g,为理论吸附量的42.5%.其对立体异构体奎宁丁也具有较好的识别作用,对结构类似物辛可宁显示一定的选择性,选择因子α分别为1.27和3.06.     

(聚苯乙烯/有机蒙脱土)/聚丙烯酸正丁酯核壳纳米复合材料的制备

采用半连续种子乳液聚合方法,制备了以聚苯乙烯(PSt)/有机蒙脱土(OMMT)为核,聚丙烯酸正丁酯(PBA)为壳的核壳纳米复合材料(CSN)。借助傅里叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)考察了CSN的粒子结构及形貌,显示CSN呈球形,核壳结构明显。通过种子用量、核壳质量配比、引发剂用量及单体总量对乳液性能的研究,结果表明,当种子用量为20%,核壳质量配比2∶1,引发剂用量0.6%(wt),单体总量45%(wt)时,乳液的固含量、转化率较高,耐水性、化学稳定性及机械稳定性较好。热重分析(TGA)表明CSN复合材料热稳定性有所提高。     

In Vivo Magnetic Particle Targeting by Local Gradient Field of Interstitial Seeds Magnetized in an Ex Vivo Uniform Field

The possibility of in vivo magnetic particle targeting by the locally induced gradient field of interstitial ferro- magnetic implants, magnetized in an ex vivo uniform field, is evaluated by a modelling analysis. A simplified 3D model analogous to a torso size, with a continuous laminar flow through the volume with the typical velocity and viscosity values of in vivo blood flow and a ferromagnetic seed inserted in the volume center vertical to the flow, is used to evaluate the magnetic particle capturing efficiency by the seed, which is magnetized in a uniform field. The initial modelling results indicate that for 1-10μm iron oxide particles transporting with a blood flow of 0.5-5 mm/s, the seeds of tungsten steel, magnet steel and cast cobalt all present an effective particle capturing efficiency, which shows a fast initial increase and a slow saturation with the increasing magnetic field, a quasilinear increase with the increasing particle size, and a nonlinear decrease with the increasing blood velocity.