转基因棉花品纱对棉铃虫抗性的研究

采用室内生物测定和田间棉铃虫危害调查方法,分析了辽宁省经济作物研究所转育的3个转基因棉花品系（4830,4877,4786）和美国构建的Bt基因棉花品系新棉33B的不同器官的抗虫性,结果表明,棉花不同器官抗虫性不同,功能叶抗虫性最强;转基因棉花4830和新棉33B抗虫性强弱没有显差异,并均高于转基因棉4877,4786,这说明中国转基因抗虫棉与美国抗虫棉具有等同的杀虫效果,转基因棉花的蛋白毒性在棉铃虫体内具有一定的残效。在田间小区种植中,4830,4877,4786和33B均表现出了对棉铃虫幼虫较高的抗虫效果,两次调查中（7月5日,7月14日）,4830,4786,33B品系均未发现棉铃幼虫,顶尖蕾铃也未发现受害现象,在4877品系中发现了少理的低龄棉铃幼虫,蕾铃受害率为3．01％,辽棉15号（CK）蕾铃受害率为10．6％,各品系之间抗性差异不明显。     

Chemical correlates of α-tocopherol (Vitamin E) alteredMalacosoma disstria herbivory inFraxinus pennsylvanica var.Subintegerrinia,green ash

The antioxidant -tocopherol (vitamin E), applied in a basal trunk band to the green ash tree,Fraxinus pennsylvanica var.subintergerrinia, elicited an alteration of foliar feeding byMalacosoma disstria larvae (Lepidoptera: Lasiocampidae). The bioassayed effects were dependent on the dosage of elicitor, the time after elicitation, and the position in the tree. Leaves for chemical analysis were collected from trees receiving two dosages and at two intervals after elicitation. Compounds in the ethyl acetate extractables from the ash tree leaves were separated by TLC and HPLC. TLC separations showed differences in the nonhydrolyzed extractables attributable to elicitor dosage and time after elicitation. TLC-resolved differences were also evident among acid-hydrolyzed samples. HPLC-resolved profiles revealed eight peaks in the nonhydrolyzed extractables that were quantitatively negatively correlated with larval feeding preference between elicited versus control foliage on at least one of the two sampling dates. Results from this study and other investigations reported in the literature indicate that the antioxidant-tocopherol (vitamin E) can function as an environmental-stress elicitor of alterable defensive chemistry in green ash and other plants.     

High-temperature superconducting microwave devices: Fundamental issues in materials, physics, and engineering

High-T _c superconductivity has generated a great deal of interest because of the challenges it presents in the fields of material science, condensed matter physics, and electrical engineering, and because of the potential applications which may result from these research efforts. Thin-film passive microwave components may become the first high-temperature superconducting (HTS) devices available for widespread use and commercialization. In this article, we review aspects of material science, physics, and engineering which directly impact high-T _c superconducting microwave devices and discuss issues which determine the performance of these devices. Methods of growing HTS thin films on large-area substrates, techniques for fabricating single-level HTS passive microwave components, and the relevant properties of high-T _c superconducting films are discussed, with a focus on thin films of the HTS material YBa₂Cu₃O_7–. Several known mechanisms for microwave loss in both the superconductor and the dielectric substrate are presented. An overview of the general classes of superconducting passive microwave devices is given, and representative microwave devices which have been recently demonstrated are described in detail. Examples of a select few HTS active microwave components are also presented. Potential microwave applications are illustrated with comparisons to current technology.     

高纯四溴双酚A双(2,3-二溴丙基)醚合成新工艺

研究了合成阻燃剂四溴双酚A双(2，3-二溴丙基)醚的新工艺，特点是通过加入表面活性剂TABS、催化剂SB和表面活性剂A的方法，提高产品纯度和降低游离酸的含量，成品的炭化温度为295℃，纯度大于95％。     

EPDM,PP及EPDM/PP阻燃化的研究进展

总结了近年来EPDM，PP及EPDM／PP阻燃化研究的进展。对EPDM，当前国内外一般采用含卤有机物，并配合少许三氧化二锑等来提高阻燃效果；对于PP，磷一溴体系阻燃效果好，发烟量低；对EPDM／PP，适用的阻燃剂少，目前只有十溴二苯醚／三氧化二锑、红磷。     

石墨粒度对低炭镁炭砖性能的影响

以电熔镁砂和4种粒度(≤0.149mm、 ≤0.074mm、≤0.044mm和≤0.01mm)的天然鳞片 石墨为主原料,在石墨含量为4%的条件下,研究了 石墨粒度对低炭镁炭砖的物理性能、抗氧化性和热震 稳定性的影响。结果表明:用细石墨取代较粗石墨 (粒度≤0.149mm)制成的镁炭砖,其物理性能、抗氧 化性和热震稳定性都有了明显的改善,且都以加入粒 度≤0.074mm石墨的效果最好。其原因是细石墨的 加入改善了镁炭砖的基质结构。石　墨     

农用杀螨剂应用、开发现状及展望

介绍了农用杀螨剂的开发简史，研究开发现状，我国农用杀螨剂的应用现状以及面临的问题等，并对杀螨剂的开发前景进行了讨论。     

利用铝矾土制备钛酸铝陶瓷

钛酸铝陶瓷是集低膨胀系数和高熔点为一体的新型陶瓷材料,传统钛酸铝的合成采用工业纯的氧化铝和二氧化钛为原料,生产成本较高。本文采用廉价的高铝矾土取代Al2O3制备钛酸铝陶瓷,实验分别取了三种铝钛比,通过性能测试,确定Al2O3:TiO2=1:0.90可制得综合性能较佳的Al2TiO5陶瓷,此时α=2.05×10-6℃-1,抗折强度σ=35Mpa,热震稳定性达到32次。     

304光亮不锈钢着色工艺研究

报道了在铬酸－硫酸着色液中加入适当的添加剂，对３０４光亮不锈钢进行了化学着色试验，测量了着色过程中的电位－时间曲线，确定了４种颜色的电位差值，还探讨了着色膜的硬化处理和封闭处理工艺。