循环氩离子轰击对等离子体增强化学气相沉积(PECVD)TiN膜耐腐蚀性能的影响

设计了循环氩离子轰击 -PECVDTiN工艺。运用扫描电子显微镜、能谱仪、恒电位仪等仪器设备 ,研究循环氩离子轰击对PECVDTiN膜耐腐蚀性能的影响及作用机理。结果表明 :循环氩离子轰击提高了膜层在硝酸和硫酸中的耐腐蚀性能。这主要是由于循环氩离子轰击强化了沉积中的反应 ,细化了TiN晶粒 ,降低了膜层中的残余氯含量。循环氩离子轰击还可能具有减少膜内缺陷、提高TiN膜致密性的作用 ,从而亦有助于提高膜的耐蚀性。     

AIB用于改进PLD沉积在机械瓣膜上的类金刚石膜的质量

用脉冲激光沉积(PLD)法在热解C制作的人工心脏机械瓣膜上沉积类金刚石(DLC)薄膜,并用3KeV的氩离子轰击(AIB)DLC薄膜。采用拉曼(Raman)光谱和X射线光电子能谱(XPS)分别对AIB前后的DLC薄膜进行检测分析,用光学显微镜观察AIB前后的DLC薄膜表面。实验结果表明:AIB不影响薄膜的黏附性。但是可以在一定程度上导致薄膜微观结构的变化和sp3/sp2比值的提高,可以在薄膜中掺杂微量的Ar元素,可以有效消除薄膜表面吸附的O,但对薄膜中C-O、C=O和COOH的影响较小。因此,离子轰击法可以作为一种改进类金刚石薄膜质量的方法。     

离子轰击辅助电子束蒸发制备含有纳米石墨结构的非晶碳膜

采用离子轰击辅助电子束蒸发技术制备了含有纳米石墨结构的碳膜。利用XRD、Ralnan和AFM等方法分析了碳膜的厚度、结构、相成分和形貌。结果表明制备的碳膜是一种具有纳米石墨结构的非晶碳膜。随着离子轰击能量的增大,碳膜的厚度随之减小,纳米石墨结构sp2团簇的尺寸变大,碳膜表面粗糙度增大,并找到了最佳的离子轰击能量。通过对Raman光谱分析发现,在最佳离子轰击能量下形成的纳米石墨结构sp2团簇尺寸大小约为2nm。     

On two control parameters of the dynamics of the anodic dissolution of copper

An experimental study of the effect of SCN⁻ ion concentration and laser bombardment intensity on the anodic dissolution of copper into an aqueous NaCl electrolyte is reported. The laser was used to accelerate the dissolution process. The results are analyzed in terms of power spectra, fractional Brownian motion theory and confocal image processing. An interpretation of the dynamic phenomena via the theory of nonlinear dynamics is also suggested.     

双聚能槽药柱的研究与应用

对中国专利产品"双聚能槽药柱"爆炸效果研究时发现,它会聚集炸药爆炸后的成缝能量并使炸药爆速变小,在采用专用对中装置后可确保聚能射流能够沿着预裂(光爆)面发挥气刃作用。这样爆破应力波作用、高压气体的膨胀作用、聚能射流的气刃作用在岩体形成裂缝的瞬间能够更完美地相互作用,从而完成了将预裂(光面)爆破和聚能爆破机理的完全结合,实现了"双聚能预裂与光面爆破综合技术"的生产性应用并获中国发明专利,数值模拟研究及模拟试验也得出了与之吻合的结论。该项专利技术可以减少造孔工作量、单位面积装药量、能源消耗50%⁶5%,可节约成本50%65%,可节约成本50%⁵5%,同时还可大大减小爆破对保留岩体的危害作用和增强岩石边坡的稳定性,因此加快了施工进度和提高了施工质量,推广该项技术无疑会创造极大的经济效益和社会效益。     

Ion bombardment of polyethylene—influence of polymer structure

Polyethylenes of various macromolecular and supermolecular structures were studied from the point of view of their susceptibility to an ion beam treatment. An influence of molecular weight (M_w), molecular weight distribution (M_w/M_n) and the degree of branching were compared within the set of low-density polyethylenes (LDPE) studied. An influence of the length of branches was compared between LDPE, linear low-density (LLDPE) and high-density (HDPE) polyethylenes. An influence of the degree of crystallinity and the morphology of a crystalline phase were compared for HDPE samples solidified under various thermal conditions and ultra-high molecular weight polyethylene (UHMWPE). Plate polymer targets ∼2 mm were bombarded with 100 keV He⁺ or 130 keV Ar⁺ ions (dose of 10¹⁴-10¹⁶ ions/cm²; ion energy stream density <0.1 μA/cm²), micromechanical properties of their surface layer (hardness, mechanical modulus and elastic recovery) determined and compared to the virgin materials.Ar⁺ ion beam bombardment generally lowers micromechanical properties of the polyethylenes, whereas He⁺ ion beam treatment makes them higher. The effect is the stronger the higher the molecular weight of polyethylene. However, a long chain branching adversely affects the modification. The degree of crystallinity facilitates an ion beam bombardment from the point of view of micromechanical properties of the materials, however, also the morphology of a crystalline phase was found to play a role.     

Carbon nitride films deposited by reactive sputtering and pulsed laser ablation

Carbon nitride films were deposited by reactive sputtering process and by pulsed laser ablation process with substrate bias. By applying the RF bias, it enables the ion irradiation on to the depositing film surface continuously. ECR plasma source was used for reactive sputtering. Nd:YAG laser (λ=532 nm, 210 mJ) was used to ablate a graphite target in the nitrogen atmosphere. The film properties were examined by XPS, Raman, nanoindentation measurement, and FE-SEM. It was shown that the films deposited by reactive sputtering had smooth surface and its hardness of approximately 30 GPa. However, the films deposited by pulsed laser ablation had uneven surface and low hardness. Both processes, the atomic composition ratio of N/C and sp³ bonding ratio increased with ion bombardment energy up to 100-150 eV, and level off above it. The maximum atomic composition ratio of N/C was 0.35 for reactive sputtering and 0.24 for laser ablation.     

基因枪法转化小麦及转基因植株的获得

应用基因枪法转化了小麦幼胚,成熟胚及胚性愈伤组织,成功地将携带有豇豆胰蛋白酶抑制剂（ＣｐＴＩ）基因以及选择标记潮霉素磷酸转移酶基因的质粒ｐＢＣＡ－Ｈｐｔ导入小麦胚性愈伤组织。通过在选择培养基上严格筛选后获得潮霉素抗体愈伤组织,并进一步分化培养获得完整的小麦再生植株。ＰＣＲ检测结果显示抗性愈伤组织和再生植株细胞内存在有目的基因序列,证实其为转基因材料。     

离子能流密度对类金刚石薄膜成膜的影响

着重讨论了离子轰击能量影响类金刚石薄膜成膜过程的机理 ,特别引入了离子能流密度即在单位时间内成膜表面的单位面积上接收到的离子轰击能量的概念 ,这就能更加正确地解释离子轰击在成膜过程中所起的作用。采用了具有特色的等离子体分解碳氢化合物结合高能离子轰击基片的方法制备类金刚石薄膜。这种兼有PVD和CVD各自优点的PCVD方法 ,能独立地分别调节轰击基片的离子能量和离子流密度。实验结果表明 ,存在一个离子能流密度的阈值。超过该阈值 ,才能得到结构致密、均匀 ,与基片结合强度好 ,硬度很高的类金刚石薄膜 ,扫描电镜对膜层形貌的显微成像和维氏硬度测试展示了离子能流密度对成膜的影响。作为佐证 ,还对薄膜进行了喇曼光谱测试和分析。     

噻吩-2,5-二羧酸的离子对液相色谱法分析

建立了测定噻吩-2,5-二羧酸的离子对反相高效液相色谱法(HPLC)。采用5μm粒径的ZOR-BAX ODS色谱柱,柱温40℃,以含有0.02mol/L四乙基碘化铵的甲醇-水(20:80V/V)为流动相进行洗脱,流量1.5ml/min,紫外检测波长272nm。噻吩-2,5-二羧酸的线性范围是0.01～20g/L,最小检测量为1.7ng。此分析方法简便、快速、准确。本方法还与紫外分光光度法作了比较。