Integrated solid-state nanopore devices for third generation DNA sequencing

Third generation DNA sequencing relies on monitoring the ionic current blockage during the DNA molecule’s threading through a nanoscale pore.It is still really tough to attain the single base discrimination on a DNA strand by merely analyzing the ionic current due to speedy DNA translocation and low spatial resolution.More integrated configurations are pursued to present versatile comparative dissimilarities of the four bases by enhancing the spatial resolution within a DNA molecule translocation event,such as transverse tunneling current,local potential change,and capacitance oriented voltage resonance.In this mini review,the insight is provided into the status quo on several functionalized techniques and methodologies for DNA sequencing and furthermore concluding remark and outlook are presented.     

大掺量磷石膏用于路基填料的性能试验研究

为探索磷石膏大掺量、规模化、资源化利用路径,分别以自制固化剂和水泥为胶凝材制备大掺量磷石膏路基填料,开展大掺量磷石膏混合料的击实试验、无侧限抗压强度试验及疏水改性试验,分析大掺量磷石膏与自制固化剂和水泥的适配性、击实特性、强度特性、耐水性能。结果表明,采用水泥或自制固化剂改性磷石膏击实曲线呈单峰变化趋势,且含水率偏低时对大掺量磷石膏混合料的干密度影响较小;相同配比时,固化剂体系大掺量磷石膏混合料7d无侧限抗压强度是水泥体系的1.5倍以上,磷尾砂与自制固化剂的适配性优于黏土,且配比为90%磷石膏+10%固化剂的大掺量磷石膏混合料7d无侧限抗压强度度达3.4MPa,经疏水改性后强度提升至4.2MPa,疏水剂与自制固化剂的复配较好地改善了磷石膏自身亲水特性,提升了其水稳性能。     

DR机房建设与验收监测的要点探讨

随着我国放射诊断学的快速发展,当前许多医院都在购置或使用医用数字化X射线摄影系统(DR)机房建设必须符合国家标准满足临床使用。本文结合日常工作中总结的经验,从DR机房的规划设计、放射防护设施施工、放射防护验收监测方面探讨了DR机房建设过程中的要点,为医院的机房建设提供参考。     

2号高炉进风面积的调节

叙述了武钢2号高炉针对原燃料条件变化进行进风面积的调整及调整效果，并对其原因进行了分析。     

添加ZrO2对铜基摩擦材料摩擦磨损性能的影响

采用粉末冶金方法制备了高速列车用铜基摩擦材料,研究了添加ZrO2的量对材料的摩擦因数、磨损量的影响规律。结果表明:在添加ZrO2的材料中,含5%(质量分数,下同)ZrO2的材料摩擦因数较高,磨损量也较大;添加8%ZrO2的材料在高速下的摩擦因数较高,磨损率较小且变化平稳。材料的磨损在较低的速度下以粘着磨损为主;随着速度的上升,磨损也逐渐变成以剥层脱落和氧化磨损的混合机制为主。     

中国铜工业1998年应采取的对策

本文拟就分析1998年铜市熊态依旧的形势,探讨中国铜企业应如何面对现实,迎接挑战.采取对策.     

CAD软件对硬件的要求

本文针对为能更好的运行ＣＡＤ软件,对所需要的配件系统进行分析比较,以达到合理配置硬件系统,提高工作效率的目的。     

关于细胞神经网络无性模板的设计

本文以连通片检测器无性模板的设计为例，给出了细胞神经网络中无性模板的设计方法及连通片检测器无性模板中各元素的数值范围。     

Effect of particle size distribution on green properties during high velocity compaction

Iron powders with two different particle size distributions were compacted by high velocity compaction. The influences of particle size distribution and impact velocity on green properties, including green density, springback, tensile strength and bending strength etc., were studied with scanning electron microscopy (SEM) and a computer controlled universal testing machine. The results show that the particle size distribution and the impact velocity strongly affect its properties. Wider size distribution results in green compact with higher density and better strength. Furthermore, springback of compacts is lower produced by the powder with wider size distribution, especially for radial springback. As impact velocity increases, its green density and green strength gradually increases, but the increasing rate of density decreases gradually. No special relation is found between springback and impact velocity. In addition, the axial springback and the bending strength are higher than the radial springback and the tensile strength, respectively.