过渡金属表面γ-氨丙基三甲氧基硅烷膜的研究

本文对在过渡金属铁、镍电极表面制备得到的γ-氨丙基三甲氧基硅烷(γ-APS)膜进行了研究。实验中对硅烷膜用X-射线光电子能谱(XPS)、现场表面增强拉曼散射光谱(SERS)和原子力显微镜(AFM)进行了表征。X-射线光电子能谱(XPS)的结果发现存在两个N1s峰,表明γ-APS膜中的氨基有两种存在方式:自由氨基和质子化氨基。实验中还发现现场表面增强拉曼散射光谱(SERS)是研究金属/γ-APS体系中界面层结构非常有效的手段,SERS结果表明硅醇羟基和氨基发生了竞争吸附,且γ-APS分子在外加电位等条件的影响下吸附状态会发生一定变化。原子力显微镜(AFM)的表征结果在微观上显示电极表面的γ-APS膜上形成了一种较规则的微孔结构,这种结构可能与基底的性质有关。     

Coupled perpendicular magnetization in Fe/Cu/Fe trilayers

Ultrathin epitaxial Fe films on Cu(1 0 0) with perpendicular magnetization have been used as templates for the preparation of FCC Fe/Cu/Fe trilayers. The magnetic anisotropy and the coupling of these films have been studied by in-situ magneto optical Kerr effect measurements and Kerr microscopy. The magnetic coupling of both Fe layers is found to be dominated by magnetostatic interaction. Adsorbate-induced spin reorientation in the top layer also causes spin reorientation in the bottom layer. The governing role of the Fe-vacuum interface for the magnetism of the whole trilayer is demonstrated.     

纳米晶复合Pr2Fe14B/α-Fe永磁材料磁性的研究

采用熔体快淬的方法制备Pr₂Fe₁₄B/α-Fe纳米晶复合永磁材料.使用振动样品磁强计(VSM)测量样品的室温磁性能.实验合金成分为(Pr_xFe_94.3-xB_5.7)_0.99Zr₁(其中x＝8.2，8.6，9.0，9.4，9.8，10.2，10.6，11.0，11.4(原子分数，%)).系统地研究了辊速及合金成分对快淬带磁性能的影响，当Pr原子分数由8. 关键词： 纳米复合永磁材料 熔体快淬 2Fe₁₄B/α-Fe')" href="#">Pr₂Fe₁₄B/α-Fe 磁性     

中子俘获瞬发γ射线数据评价(英文)

简要地介绍了中子俘获瞬发γ射线数据及其衰变纲图的评价方法技术、主要程序及其功能、数据评价流程、强度平衡检验，以及对A=1-44的稳定核素和A>190的部分稳定核素的热中子俘获瞬发γ射线数据及其衰变纲图评价的具体应用.The method of prompt γ-ray data evaluation for neutron capture and how to calculate the prompt γ-ray intensities of neutron capture have been briefly presented. The prompt γ-ray data of thermal-neutron capture of some stable nuclei for A=1-44 and A>190 have been evaluated. The ENSDF format has been adopted. The checks of intensity balance and format have been made. The examples are given to illustrate its application.     

A remarkable stereoselectivity switching upon solid-state versus solution-phase enantiodifferentiating photocyclodimerization of 2-anthracenecarboxylic acid mediated by native and 3,6-anhydro-γ-cyclodextrins

The enantiodifferentiating [4+4] photocyclodimerization of anthracenecarboxylic acid (AC) mediated by native, mono- and di-3,6-anhydro-γ-cyclodextrins was investigated in both aqueous solution and solid-state. The solid-state photolyses gave inherently disfavored head-to-head photodimers in much higher chemical and optical yields than in the aqueous solution.     

两亲嵌段共聚物聚乙二醇-聚谷氨酸苄酯纳米粒药物载体的合成研究

用磺酸酯法制备单端氨基聚乙二醇引发剂,引发谷氨酸苄酯羧酸酐开环聚合,生成可生物降解的两亲嵌段共聚物聚乙二醇﹣聚谷氨酸苄酯(PEG-PBLG),用IR,NMR和GPC表征了共聚物。用超微透析法制备PEG-PBLG聚合物纳米粒,荧光芘探针法测定纳米粒的临界聚集浓度(cac)。紫外分光光度计考察纳米粒对疏水性药物的增溶作用,PEG-PBLG可作为亚微粒药物输送系统的载体。     

在离子液体中一步法合成吡唑[5,4-b]-γ-吡喃衍生物

芳醛、丙二腈与4,5-二氢-3-甲基-5-氧代-1-苯基吡唑在离子液体[bmim][BF₄]中反应, 合成了2-氨基-4-芳基-3-氰基-5-甲基-7-苯基吡唑[5,4-b]-γ-吡喃衍生物, 该法快速、高效, 是一种洁净的合成方法. 产物的结构通过红外光谱、核磁共振氢谱和元素分析进行表征.     

氧化共沉淀法制备纳米级掺锑α—Fe2O3气敏陶瓷粉料

氧化共沉淀法制备纳米级掺锑α┐Ｆｅ２Ｏ３气敏陶瓷粉料王忠春＊＊刘尔生陈耐生＊黄金陵（福州大学化学系福州３５０００２）关键词α－Ｆｅ２Ｏ３陶瓷，锑掺杂气敏材料，纳米材料１９９６－１０－０５收稿，１９９７－０４－２２修回福建省科委资助项目＊＊现在上海硅酸...     

ELECTROSPRAYING/ELECTROSPINNING OF POLY(γ-STEARYL-L-GLUTAMATE): FORMATION OF SURFACES WITH SUPERHYDROPHOBICITY

  Electrospraying/electrospinning of poly(γ-stearyl-L-glutamate) (PSLG) was investigated on a series solutions with different concentrations in chloroform. Field emission scanning electron microscopy (FESEM) and attenuated total reflectance Fourier transform infrared spectroscopy (FT-IR/ATR) were used to characterize the morphology and structure of the electrosprayed/electrospun polypeptide mats. It was found that electrospraying of PSLG with concentrations lower than 16 wt% afforded beads, while microfibers could be electrospun at the concentration of 22 wt%. The hydrophobicity of the electrosprayed/electrospun PSLG mats was investigated with static water contact angle (WCA) and tilt angle measurements. It was demonstrated that the superhydrophobic surfaces of PSLG with WCAs and tilt angles in the ranges of 150°-170° and 16.5°-4.2°, respectively, were obtained through electrospraying/electrospinning process.     

γ-射线辐照对尼龙6纤维结构的影响

<正> 过去的大多数研究表明,高能射线辐照会引起聚乙烯及聚丙烯等稀烃类聚合物分子链交联及降解,而且会导致结晶度下降。张利华等人最近的研究表明,对于尼龙1010塑料,仅当辐照剂量高到一定程度后,辐照才会破坏结晶。此外,Stowe等人曾经研究过近紫外线对尼龙66纤维结构的影响,结果表明,在空气气氛中的近紫外辐照主要导致尼龙66纤维降解,并使纤维结晶度提高。有关高能射线辐照对高度取向的合成纤维结构及性能的影响的研究尚不多见。本工作将讨论γ-射线对于尼龙6纤维结构的影响。