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101.
α-1-Fetoprotein (AFP) is an important tumor marker for the diagnosis,and even early detection of original liver carcinoma. In clinical practice its determination is only performed with IRMA or spectrophotometric ELISA. In comparison with IRMA, the later is a more welcome procedure and has been widely used to, detect AFP. However, its sensitivity is inadequate in many assays due to the influence of specimen color and some experimental factors. This work uses a gold disk electrode (0.5 mm diameter) as working electrode and improves the sensitivity detecting AFP for about ten times. 相似文献
102.
Norepinephrine (NE) is one of the most important biochemical messengers. The oxidation of NE at various electrodes has been extensively studied. The ease of NE oxidation lead to the development of convenient and rapid procedures for measuring NE levels using various electrochemical methods. A serious problem is that ascorbic acid (AA) often co-exists with NE, resulting in interference in NE determinations. This work describes the electrocatalytical activity of[Os(bpy)2(PVP)10Cl]+/Nafion modified graphite electrode for trace NE determination. The modified electrode can eliminate the interference from AA and uric acid (UA) in NE determinations,thus could be used as an amperometric sensors for the detection of NE levels. 相似文献
103.
采用原子力显微镜(AFM)、俄歇电子能谱(AES)和显微压痕分析等手段对射频等离子体增强化学气相沉积法制备的掺氮类金刚石(DLC:N)薄膜的微观结构和力学性能进行了研究.结果表明,随着含氮量的增加,DLC薄膜的AFM表面形貌中出现了几十纳米的颗粒,原子侧向力显微镜和AES分析表明这种纳米颗粒是x大于0.126的非晶氮化碳CNx结构.这种非晶DLC/CNx的纳米复合结构,减小了薄膜的内应力,从而提高了薄膜与衬底的附着力.
关键词:
类金刚石碳膜
微观结构
附着特性 相似文献
104.
给出了数学表达式屏幕输入的C^ 程序,并用类进行了封装.封装之后,成了一个独立模块.以Newton求根迭代程序为例说明,该模块可以方便地嵌入在需要它的其他程序里. 相似文献
105.
The dynamics of an ensemble of two-level atoms injected into a single-mode cavity is studied in the exact atom-field interaction situation, in which the counter-rotating terms describing the so-called virtual photon processes neglected in the rotating-wave approximation, are considered. The cavity mode is driven by the injected classical field,and the atom is prepared in a coherent superposition of the two levels. We first derive the generalized Lorenz-Haken equation by using the technique of quantum Langevin equation, and then numerically study the dynamics of this equation.We find that the virtual photon processes have strong effects on the dynamics, which can cause the trajectory in phase space of strange attractor spiral around four focus points, and the trajectory is modulated by virtual photon processes.The chaos region in parameter space is now enlarged. It should be stressed that the strange attractor can exist in optical bistability, and whether the atomic coherences and classical field can inhibit chaos depends on the laser frequency. 相似文献
106.
107.
Digital pulse shape discrimination methods for n-γ separation in an EJ-301 liquid scintillation detector
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WAN Bo ZHANG Xue-Ying CHEN Liang GE Hong-Lin MA Fei ZHANG Hong-Bin JU Yong-Qin ZHANG Yan-Bin LI Yan-Yan XU Xiao-Wei 《中国物理C(英文版)》2015,39(11):116201-116201
A digital pulse shape discrimination system based on a programmable module NI-5772 has been established and tested with an EJ-301 liquid scintillation detector. The module was operated by running programs developed in Lab VIEW, with a sampling frequency up to 1.6 GS/s. Standard gamma sources22 Na,137Cs and60 Co were used to calibrate the EJ-301 liquid scintillation detector, and the gamma response function was obtained. Digital algorithms for the charge comparison method and zero-crossing method have been developed. The experimental results show that both digital signal processing(DSP) algorithms can discriminate neutrons from γ-rays. Moreover,the zero-crossing method shows better n-γ discrimination at 80 ke Vee and lower, whereas the charge comparison method gives better results at higher thresholds. In addition, the figure-of-merit(FOM) for detectors of two different dimensions were extracted at 9 energy thresholds, and it was found that the smaller detector presented better n-γseparation for fission neutrons. 相似文献
108.
利用X射线光电子能谱、紫外光电子能谱和低能电子衍射研究了Ni纳米颗粒在ZrO2(111)薄膜表面的生长模式、电子结构及热稳定性. ZrO2(111)薄膜外延生长于Pt(111)单晶表面,厚度约为3 nm.结果表明,当Ni气相沉积到ZrO2(111)薄膜表面上时,遵循Stranski-Krastanov生长模式,即先二维生长至0.5 ML(monolayer),然后呈三维岛状生长.随着覆盖度的减小, Ni 2p3/2峰逐渐向高结合能位移.利用俄歇参数法分析发现,引起该峰向高结合能位移的主要原因来源于终态效应的贡献,但在低的Ni覆盖度时,也有部分初态效应的贡献,说明Ni在ZrO2表面初始生长时,两者存在较强的界面相互作用, Ni向ZrO2衬底传递电荷,形成带部分正电荷的Niδ+.两种不同覆盖度(0.05和0.5 ML)的Ni/ZrO2(111)模型催化剂热稳定性研究表明,当温度升高时, Ni逐渐被氧化成Ni2+,并伴随着向ZrO2衬底的扩散.本文从原子水平上认识了Ni与ZrO2表面的相互作用和界面结构,为理解实际ZrO2担载的Ni催化剂结构提供了重要的依据. 相似文献
109.
合成了三种2, 6-双(N-乙基苯并咪唑)吡啶炔基铂(Ⅱ)配合物(2-4),其中配合物2的炔基配体为抗癌药物埃罗替尼.利用紫外-可见(UV-Vis)吸收光谱,圆二色(CD)光谱,荧光共振能量转移(FRET)等方法研究了铂(Ⅱ)配合物与人体端粒(Hetelo)和c-myc原癌基因(c-myc)G-四链体的相互作用.实验结果表明,所合成的铂配合物与G-四链体具有较强的相互作用(Ka > 106 L·mol-1),在无碱金属离子存在条件下能诱导G-四链体的形成.含苯乙炔基团的配合物2、3能使c-myc G-四链体的熔解温度上升24 ℃以上,而含丙炔基团的铂配合物4仅使c-mycG-四链体的熔解温度升高9.0 ℃,表明炔基结构对铂(Ⅱ)配合物与G-四连体的作用有较大影响.配合物2对人肺癌细胞A549的细胞毒性明显高于埃罗替尼及其他两种配合物3、4. 相似文献
110.