Determination of Kinetic Parameters and Metal Ions in Urea-Urease System Based on the Biochemical Reaction Heat Induced Laser Beam Deflection

A new analytical method for the determination of urea-urease system based on biochemical reaction heat induced laser beam deflection is presented in this paper. With the method, the Michaelis constant (K-m) of urease and apparent inhibition constant (K-i) of some metal ion inhibitors were measured respectively. This method was also used for the quantitative determination of metal ions with satisfactory result.

Aluminum ion beam surface modification of elastic metallic-plastic pads for improving tribological properties

Elastic metallic-plastic pads（EMP） were irradiated by low energy aluminum ion in a metal vapor vacuum arc（MEVVA） 80-10 implantation system. The samples were irradiated with 20keV Al ion with the influx from 1×1015 to 1×1016 Al/cm2. Then the as-irradiated samples were measured by ESCA, XRD, AFM/FFM and a nano-probe. It is found that the hardness of as-irradiated samples is 5-6 times as that of the pristine ones. The worn depth of sample implanted at ion influx of 1×1016 Al/cm2 is about one eighth of that of the pristine sample at the same load. The XRD results show that there are some Al2O3 and AlF3 intermingled with the phase of polytetrafluoroethylene（PTFE）. The experimental results reveal that the tribological properties of EMP can be significantly improved by the ion beam surface modification.

STUDY OF THE FOCUSED ION BEAM AND ITS APPLICATION TO METAL IMPLANTATION MODIFICATION

The properties and designment of the strong focusing lens system and the application to metal modification of gear cutting tools are described. The focused ion beam produced by a special three asymmetric voltage lens has the unique features of short midfocal length, strong focusing and omitted focusing electric power. These properties of strong focusing lens system are due to the application of the high energy ratio of 20 to 50 onto the lens.

Production of intense highly charged ion beams by IMP 14.5 GHz electron cyclotron resonance ion source

A new 14.5 GHz Electron Cyclotron Resonance (ECR) ion source has been constructed over the last two years. The source was designed and tested by making use of the latest results from ECR ion source development, such as high mirror magnetic field, large plasma volume, and biased probe. 140uA of O^7+, 185uA of Ar^11+ and 50uA of Xe^26+ could be produced with a RF power of 800 W. The intense beams of highly charged metallic ions are produced by means of the method of a metal evaporation oven and volatile compound through axial access. The test results are 130uA of Ca^11+, 70uA of Ca^12+ and 65uA of Fe^lo+. The ion source has been put into operation for the cyclotron at the institute of Modern Physics (IMP).

Metallic glass formation in the ternary Ni-Nb-Mo system by ion beam mixing

Glass forming ability of the ternary Ni-Nb-Mo system was studied by ion beam mixing of the Ni-Nb-Mo multilayered films.In the experiment,metallic glasses i.e.amorphous alloys were formed in the Ni51Nb19Mo30,Ni52Nb35Mo13,Ni61Nb15Mo24 and Ni72Nb20Mo8 multilayered films,while only solid solutions were obtained in the Ni24Nb29Mo47 and Ni26Nb53Mo21 multilayered films.It turned out that the Ni concentration played a dominating role in affecting the glass-forming ability of the system.Besides,thermodynamic calculations predicted a favored composition region for metallic glass formation,matching well with the observations from ion beam mixing.

Synthesis of metallic glasses and metallic glass based composites in the Cu-Mo-Hf system by ion beam mixing

Single-phase and dual-phase metallic glasses as well as metallic glass based composites were synthesized in the Cu-Mo-Hf ternary metal system by 200 keV xenon ion beam mixing of far-from-equilibrium. It was found that Mo-Hf-based and Cu-Mo-based single-phase metallic glasses could be obtained at compositions around Cu17Mo20Hf63 and Cu34Mo57Hf9, respectively. Interestingly, at the nearly equal-atomic stoichiometry of Cu38Mo31Hf31, a dual-phase Cu-Mo-Hf metallic glass, consisting both of the Mo-Hf-based and Cu-Mo-based phases, was first obtained at relatively low irradiation doses ranging from (1-5)×1015 Xe+/cm2, and a single-phase metallic glass was eventually obtained at a dose of 7×1015 Xe+/cm2. In addition, two glass-based composites were obtained at the compositions of Cu14Mo62Hf24 and Cu77Mo14Hf9, and they consisted of the Mo-Hf based and Cu-Mo based metallic glasses, dissolved with some uniformly distributed BCC Mo-based and FCC Cu-based crystalline solid solutions, respectively. The formation mechanism of the above described non-equilibrium alloy phases was also discussed in terms of the atomic collision theory.

宽束离子束刻蚀快速加工金属纳米间隙结构

提出并演示了利用宽束离子束刻蚀方法一次性对多个杠铃形金属纳米结构进行“横向抽减”,形成极小纳米间隙,从而实现多个金属纳米间隙结构的快速加工。利用电子束曝光定义图形化抗蚀剂结构,通过传统的金属沉积和湿法剥离将抗蚀剂图案转移至杠铃形金属纳米结构,最后使用宽束离子束刻蚀进行修剪。实验表明,精确控制刻蚀时间可以使杠铃形结构的两个纳米天线间的间隙距离达到10 nm以下,通过结合基于HSQ负性抗蚀剂的图案化工艺,可在HSQ纳米模板上制得悬空金属纳米间隙结构。利用表面结构形貌表征获得刻蚀过程中纳米结构的形态演变规律,并通过系统的实验和模拟验证了悬空金属间隙结构用于表面增强拉曼散射的优势。该方案为多个极小金属纳米间隙结构的一次成型提供了新的思路,在大面积拉曼传感衬底的低成本高效制备方面具有可观的应用前景。

强脉冲离子束在金属中引起的应力波效应

金属在强脉冲离子束辐照及其后的快速冷却过程中所经历的应力过程是强脉冲离子束金属材料改性的最重要的机制之一。 对应于这种过程, 金属材料的微观结构和微硬度发生了改变。本文以45#钢和纯铝为样品, 将实验中测量到的不同强度的强脉冲辐照后样品微硬度和微观结构的变化与热力学计算所描述的热力学过程相对照, 解释了出现微硬度双峰是由于应力波的形成和传播使然,并预言了由于应力波的在样品背面的反射,在较强能通量的强脉冲离子束辐照下样品背表面一定深度处也会出现微硬度增加的现象,该现象已被实验所证实。

衬底负偏压对线性离子束DLC膜微结构和物性的影响

采用一种新型线性离子束PVD技术制备出大面积类金刚石薄膜(DLC膜),研究了衬底负偏压对薄膜微结构和物性的影响.结果表明:制备出的类金刚石薄膜在300 mm×100 mm范围内纵向厚度均方差约10-12 nm,横向薄膜厚度均方差约2-4 nm.随着衬底偏压的提高,薄膜中sp^3键的含量先增加后减小,在衬底偏压为-100 V时sp^3键的含量最大;DLC膜的残余应力、硬度和弹性模量与sp^3键的含量呈近似线性的关系,在衬底偏压为-100 V时其最大值分别为3.1 GPa、26 GPa和230 GPa.DLC薄膜的摩擦学性能与薄膜中sp^3碳杂化键的含量密切相关,但是受衬底偏压的影响不大,其摩擦系数大多小于0.25.偏压对磨损的影响很大,在偏压比较低(0～-200 V)时,薄膜的磨损率约为10^(-8)mm^3/N·m,偏压升高到300 V磨损率急剧提高到10^(-7)mm^3/N·m.

金属等离子体浸没离子注入技术合成NbN膜

利用无大颗粒的金属等离子体浸没增强沉积技术 ,在Si基体上进行动态离子束增强沉积NbN ,在低温下制成了NbN薄膜 .薄膜表面细密光滑 ,退火前其硬度 >16 .8MN·mm- 2 ,退火后硬度 >16 .0MN·mm- 2 .

Preparation of Y-Ba-Cu-O film on metal substrate with buffer layers deposited by ion beam assisted deposition

Ion beam assisted pulsed laser deposition of biaxially aligned yttria-stabilized zirconia (YSZ) was used to produce a buffer layer for YBCO film on polycrystalline metallic substrate.The YSZ layers were biaxially aligned with (001) axis normal to the substrate.The minimum FWHM of (111) phi-scan of the YSZ was 19,and the minimum FWHM of the rocking curve of YSZ was 4.5.Highly c-axis oriented biaxially aligned YBCO thin films were epitaxially grown by laser ablation on these layers,with JC(77K,0T)=2.1×105A/cm2,Tc0=90.5 K.

离子束溅射沉积Co膜光学特性的尺寸效应研究

本文采用离子束溅射沉积了不同厚度的Co膜 ,利用Lambda 90 0分光光度计 ,对不同厚度的Co膜从波长为 310nm到 130 0nm范围测量了薄膜的反射率和透射率。选定波长为 310、35 0、4 0 0、4 30、5 5 0、6 32、80 0、12 0 0nm时对薄膜的反射率、透射率和吸收率随薄膜厚度变化的关系进行讨论。实验结果显示 ,Co膜的光学特性都有明显的尺寸效应。对在可见光范围内同一波长时的反射率和透射率随薄膜厚度变化关系的实验结果作于同一图上 ,发现反射率曲线与透射率曲线都有一个处在网状膜阶段的交点 ,这个交点对应的厚度作为特征厚度 。

液态金属离子源聚焦离子束系统在微米/纳米技术中的应用

随着微米／纳米科学技术的发展，微细加工微区分析所用的主要技术之一──聚焦离子束技术引人注目．本文简述了具有液态金属离子源的聚焦离子束技术的主要功能，着重报道了近年来该技术在下述领域中的应用：（1）半导体大规模集成电路器件的集成、失误诊断和修复．（2）光电子集成技术中量子阱激光器和光纤相位掩模的制备及量子效应研究．（3）超导器件和真空微电子器件的研制．（4）二次离子质谱分析和透射电子显微镜样品的制备．

强脉冲离子束辐照金属材料表面热力学效应计算

简要讨论了强脉冲离子束与金属靶材料相互作用的理论模型 ,以此为基础应用数值计算的方法模拟计算了离子能量为 1 .0 Me V和 3 0 0 ke V,束流密度分别为 1 0 A/ cm2 ,50 A/cm2 和 1 0 0 A/ cm2 的质子束与金属铝靶材料相互作用时的热力学效应 ,给出了铝在辐照后内部的温度分布、温度梯度分布 ,以及温度变化速率 (加热速率与冷却速率 )、热激波的产生与传播过程及应力等模拟计算结果。

聚焦离子束加工技术及其应用

对聚焦离子束加工技术在集成电路芯片的诊断与修改、修复光刻掩模缺陷、制作透射电镜样品以及多用途微切割上的应用作了详细介绍。

聚焦离子束系统液态金属离子源的研制

设计了一种聚焦离子束系统用液态金属离子源(Liquid Metal lon Source-LMIS),本文对该源组件结构的设计、发射针尖的腐蚀工艺、挂金属镓工艺、测试系统的设计作了介绍;然后对该离子源的I-V特性、角电流密度、稳定性以及寿命等性能进行了测试。实验结果表明,该源的各项指标均达到了聚焦离子束系统的要求,并对影响源性能的因素进行了分析,从而为合理有效地设计液态金属离子源提供启示。

溅射方位对IBS沉积TbDy-Fe薄膜性质的影响

本文采用铸造合金靶材和离子束溅射 (IBS)技术制备TbDy Fe超磁致伸缩薄膜 (GMFs) ,研究了不同溅射方位 (α角 )对冷基片成膜过程和薄膜性质的影响。结果表明 ,在给定的溅射角范围内 ,薄膜表面平整光滑 ,组织致密 ,膜厚均匀且与基片结合良好 ,膜的结构均为非晶态 ;成膜生长速率、膜层成份以及λ值随α角的改变均呈现规律性的变化 ,当α角为α6左右时 ,沉积速率最大 ;在α角为α5左右范围内 ,膜层的成份最接近于靶材成份 ;α角在α4附近时用Tam法试验测定在Hmax=0 5 7T下的磁伸值λ∥ 可达 970× 10 -6,在中低场强H =0 2 5T下 ,λ∥ 值达到 710× 10 -6。

镓液态金属离子源的制备

镓液态金属离子源广泛应用于聚焦离子束技术 ,本文介绍了一种利用电子轰击的方法制备镓液态金属离子源的工艺和设备 ,测试了源的 I- V发射特性曲线 ,d I/ d V≈ 0 .0 5 ( μA/ V) ,进行了新旧工艺下电流发射稳定度的比较 ,最佳源发射稳定度大于 95 % ,寿命大于 1 0 0 0小时。

离子注入材料改性用强流金属离子源

为满足离子注入材料改性研究和实际应用的需要。研制了一个金属蒸汽真空弧(简称MEVVA)离子源.这是一新型离子源种,它利用阴极和阳极间的真空弧放电原理由阴极表面直接产生高密度金属等离子体,经一多孔三电极系统引出得到强流金属离子束.该源脉冲工作方式,已引出Al,Ti,Fe,Cu,Mo和W等离子,脉冲离子束流强度为0.6～1.26A,Ti的平均束流强度已达10mA.引出束流大小与源的工作参数、引出结构和电压以及阴极材料有关。该源没有气体负载,工作真空度为3×10^(-4)Pa。