Anne Fallon

Some fundamental concepts of catalysis are not fully explained but are of paramount importance for the development of improved catalysts. An example is the concept of structure-insensitive reactions, where surface-normalized activity does not change with catalyst metal particle size. Here we explore this concept and its relation to surface reconstruction on a set of silica-supported Ni metal nanoparticles (mean particle...

An ethanol gas sensor based on carbon nanofibers (CNFs) with various densities and nanoparticle functionalization was investigated. The CNFs were grown by means of a Plasma-Enhanced Chemical Vapor Deposition (PECVD), and the synthesis conditions were varied to obtain different number of fibers per unit area. The devices with a larger density of CNFs lead to higher responses, with a maximal...

A method is presented to directly measure the mass output of an impaction printer coupled with a spark ablation generator. It is based on a quartz crystal microbalance and shown to be reliable in quantifying mass deposition rate. Here, the method is demonstrated with an Au nanoparticle aerosol synthesized under several spark ablation and deposition settings. Changes in the deposition...

In this study, an ambient–spark–produced–Au– nanoparticle–laden nitrogen gas was mixed with an atomized solution of 1–hexanethiol and ethanol (EtOH). By increasing the thiol concentration from 0.1% to 1.0% (v/v), the size distribution of merged particles (Au–thiol) was changed from bimodal to unimodal configuration. The latter phenomenon is attributed to quantitative incorporation of Au nanoparticles into atomized particles. Measurements of cell...

Spark ablation in gas (SAG) technology has the characteristics of being green, fast quenching, fast dynamics and specializes in producing metallic nanoparticles with a clean surface, small size, and abundant defects. In this study, Ag nanoparticles were prepared via SAG and in situ loaded on a carbon fibre through nitrogen flow. The effect of the carrier gas flow rate and...

Researchers have reported the observation of long-lived Floquet prethermal states in a bulk solid composed of dipolar-coupled 13C nuclei in diamond at room temperature. For precessing nuclear spins prepared in an initial transverse state, we demonstrate pulsed spin-lock Floquet control that prevents their decay over multiple-minute long periods. Researchers observed Floquet prethermal lifetimes 𝑇’2 ≈90.9s, extended >60,000-fold over the nuclear...

Video below shows some hints & tips - even a real-life problem solved by the Check Standard! It’s all well and good performing the calibration even if you are a seasoned user of VNA’s. But it is good practice to check your calibration afterwards. https://www.youtube.com/embed/dlMYyY37TCI To speak with one of our Sales & Applications Engineers please call 01582 764334 or click here to email. Lambda Photometrics...

Introducing basic VNA measurements and considerations when testing RF Devices: How do I test my device if the connectors are different genders or if my RF test leads have different genders? Do I need to add an adapter into my calibration set-up? Can I get around this problem? How about when I’ve made my calibration, can I check that is...

Creating and analyzing signals with Proteus and MATLAB takes a few simple steps. In this application note we show how to generate and receive a WLAN beacon signal at 2.4GHz in the instruments’ first Nyquist Zone. The code can easily be modified to create a signal in the second Nyquist zone, all the way up to the WiFi-6 frequency extension...

BackgroundRADAR (“Radio Detection And Ranging”) is a system that uses electromagnetic waves to identify an object, its direction, relative speed, or even for 2D & 3D imaging. Radars help identify both fixed & moving objects such as aircraft, ships, vehicles, weather formations, and terrain. Radars use transmitters that emit electromagnetic waves that are reflected by a target (“Echoes”) and detected...