Characteristics of Resistance Triggering of a Pulsed Vacuum Arc Ion Source

Triggering scheme is a significant factor that may influence the process of vacuum arc initiation. In this work, the characteristics of resistance triggering of a pulsed vacuum arc ion source are investigated and compared with the independent pulse generator triggering. The results show that although the resistance triggering method is capable of triggering a vacuum arc ion source by properly choosing the resistance and electric parameters, it inevitably increases the rise time of the arc current. A high speed multiframe camera is used to reveal the transition process o~ arc initiation during one shot. From the images it is conjectured that the lower voltage between the cathode and the anode may be the reason that leads to the lower transition speed of discharge at the moment of arc initiation.

Effects of Three Typical Resistivity Models on Pulsed Inductive Plasma Acceleration Modeling

The effects of three different typical resistivity models（Spitzer, Z＆L and M＆G） on the performance of pulsed inductive acceleration plasma are studied. Numerical results show that their influences decrease with the increase of the plasma temperature. The significant discriminations among them appear at the plasma temperature lower than 2.5 eV, and the maximum gap of the pulsed inductive plasma accelerated efficiency is approximately 2.5%.Moreover, the pulsed inductive plasma accelerated efficiency is absolutely related to the dynamic impedance parameters, such as voltage, inductance, capacitance and flow rate. However, the distribution of the efficiency as a function of plasma temperature with three resistivity models has nothing to do with the dynamic impedance parameter.

Enhanced resistance switching stability of transparent ITO/TiO_2/ITO sandwiches

We report that fully transparent resistive random access memory （TRRAM） devices based on ITO/TiO2/ITO sandwich structure, which are prepared by the method of RF magnetron sputtering, exhibit excellent switching stability. In the visible region （400 800 nm in wavelength） the TRRAM device has a transmittance of more than 80%. The fabricated TRRAM device shows a bipolar resistance switching behaviour at low voltage, while the retention test and rewrite cycles of more than 300,000 indicate the enhancement of switching capability. The mechanism of resistance switching is further explained by the forming and rupture processes of the filament in the TiO2 layer with the help of more oxygen vacancies which are provided by the transparent ITO electrodes.

Challenging Nanopores with Analyte Scope and Environment

Nanopores are nanofluidic channels formed through thin membranes that can deliver standout single-molecule and single-particle sensing capabilities.Analytical targets include small molecules and nanoparticles,and the DNA,protein,and glycan biopolymers underpinning genomics,proteomics,and glycomics.Detection-notably even in the simplest implementation,resistive-pulse sensing-does not inherently require sample labeling and,thus,offers the potential for general sensing util-ity combined with the prospective benefits of reduced sample processing requirements.A key pursuit for biopolymer sens-ing is the characterization of monomer sequence.This review article will provide an overview of the use of nanopores for general chemical sensing and-omics-related applications,writ-large.The broad analyte scope provides fertile ground for a discussion of principles governing nanopore sensing and considerations useful for guiding nanopore development.For nanopores to be effective in the face of broad analyte scope,stringent requirements on analytical performance must be met within the particular analyte class without sacrificing the operational flexibility necessary to be responsive across classes presenting very different physical and chemical challenges.These sample-driven challenges provide a unifying framework for discussing aspects of nanopore fabrication,properties,and integration;sensing paradigms,performance,and prospects;fundamental electrokinetic and interfacial phenomena;and practical challenges facing the use and further development of nanopore devices.

Observation of an EPIR Effect in Nd_(1-x)Sr_xMnO_3 Ceramics with Secondary Phases

Nd1-xSrxMnO3 （x ： 0.3, 0.5） ceramics containing a secondary phase are synthesized by high-energy ball milling and post heat-treatment method. The 4-wire and 2-wire measuring modes are used to investigate the transport character of the grain/phase boundary （inner interface） and electrode-bulk interface （outer interface）, respectively, and the results indicate that there is a similar nonlinear I-V behaviour for both of the inner and outer interfaces, however, the electric pulse induced resistance change （EPIR） effect can only be observed at the outer interface.