Cold plasma for the disinfection of industrial food-contact surfaces: An overview of current status and opportunities

Food safety is the primary goal for food and drink manufacturers. Cleaning and disinfection practices applied to the processing environment are vital to maintain this safety; yet, current approaches can incur costly downtime and the potential for microorganisms to grow and establish, if not effectively removed. For that reason, manufacturers are seeking nonthermal, online, and continuous disinfection processes to control the microbial levels within the processing environment. One such emerging technique, with great potential, is cold atmospheric pressure plasma (CAP). This review presents the latest advances and challenges associated with CAP-based technologies for the decontamination of surfaces and equipment found within the food-processing environment. It provides a detailed overview of the technology and a comprehensive analysis of the many CAP-based antimicrobial studies on food-contact surfaces and materials. As CAP is considered an emerging technique, many of the recent studies are still in the preliminary stages, with results obtained under widely different conditions. This lack of cohesive information and an inability to directly compare CAP systems has greatly impeded technological development. The review further explores the challenge of scaling CAP technology to meet industry needs, considering aspects such as regulatory constraints, environmental credentials, and cost of use. Finally, a discussion is presented on the future outlook for CAP technology in this area, identifying key challenges that must be addressed to promote industry uptake.     

Monitoring Support for Water Distribution Systems based on Pressure Sensor Data

Water Resources Management - The increasing age and deterioration of drinking water mains is causing an increasing frequency of pipe bursts. Not only are pipe repairs costly, bursts might also lead...     

Electrical Characterization of Individual Cesium Lead Halide Perovskite Nanowires Using Conductive AFM

Perovskite nanostructures have attracted much attention in recent years due to their suitability for a variety of applications such as photovoltaics, light-emitting diodes (LEDs), nanometer-size lasing, and more. These uses rely on the conductive properties of these nanostructures. However, electrical characterization of individual, thin perovskite nanowires has not yet been reported. Here, conductive atomic force microscopy characterization of individual cesium lead halide nanowires is presented. Clear differences are observed in the conductivity of nanowires containing only bromide and nanowires containing a mixture of bromide and iodide. The differences are attributed to a higher density of crystalline defects, deeper trap states, and higher inherent conductivity for nanowires with mixed bromide–iodide content.     

High‐TC Interfacial Ferromagnetism in SrMnO3/LaMnO3 Superlattices

Heterostructures of strongly correlated oxides demonstrate various intriguing and potentially useful interfacial phenomena. LaMnO₃/SrMnO₃ superlattices are presented showcasing a new high‐temperature ferromagnetic phase with Curie temperature, T_C ≈360 K, caused by electron transfer from the surface of the LaMnO₃ donor layer into the neighboring SrMnO₃ acceptor layer. As a result, the SrMnO₃ (top)/LaMnO₃ (bottom) interface shows an enhancement of the magnetization as depth‐profiled by polarized neutron reflectometry. The length scale of charge transfer, λ_TF ≈2 unit cells, is obtained from in situ growth monitoring by optical ellipsometry, supported by optical simulations, and further confirmed by high resolution electron microscopy and spectroscopy. A model of the inhomogeneous distribution of electron density in LaMnO₃/SrMnO₃ layers along the growth direction is concluded to account for a complex interplay between ferromagnetic and antiferromagnetic layers in superlattices.     

Highly Conductive Thin Uniform Gold‐Coated DNA Nanowires

Over the past decades, DNA, the carrier of genetic information, has been used by researchers as a structural template material. Watson‐Crick base pairing enables the formation of complex 2D and 3D structures from DNA through self‐assembly. Various methods have been developed to functionalize these structures for numerous utilities. Metallization of DNA has attracted much attention as a means of forming conductive nanostructures. Nevertheless, most of the metallized DNA wires reported so far suffer from irregularity and lack of end‐to‐end electrical connectivity. An effective technique for formation of thin gold‐coated DNA wires that overcomes these drawbacks is developed and presented here. A conductive atomic force microscopy setup, which is suitable for measuring tens to thousands of nanometer long molecules and wires, is used to characterize these DNA‐based nanowires. The wires reported here are the narrowest gold‐coated DNA wires that display long‐range conductivity. The measurements presented show that the conductivity is limited by defects, and that thicker gold coating reduces the number of defects and increases the conductive length. This preparation method enables the formation of molecular wires with dimensions and uniformity that are much more suitable for DNA‐based molecular electronics.     

Scanning Tunneling Microscopy and Spectroscopy of Novel Silver–Containing DNA Molecules

The quest for a suitable molecule to pave the way to molecular nanoelectronics has been met with obstacles for over a decade. Candidate molecules such as carbon nanotubes lack the appealing trait of self‐assembly, while DNA seems to lack the desirable feature of conductivity. Silver‐containing poly(dG)–poly(dC) DNA (E‐DNA) molecules have recently been reported as promising candidates for molecular electronics, owing to the selectivity of their metallization, their thin and uniform structure, their resistance to deformation, and their maximum possible high conductivity. Ultrahigh vacuum (UHV) scanning tunneling microscopy (STM) of E‐DNA presents an elaborate high‐resolution morphology characterization of these unique molecules, along with a detailed depiction of their electronic level structure. The energy levels found for E‐DNA indicate a novel truly hybrid metal–molecule structure, potentially more conductive than other DNA‐based alternatives.     

数字工厂--数字制造教学与研究中的技术个案

１IntroductionWiththeimpactofinformationtechnologyandcomputernetworking熏thecoreofmanufacturingactivitieshasshiftedfromphysicalproductiontosystematicprocessingofinfor鄄mation眼１演．Tocaterforthischange熏manufacturerstodaymustbewellversedwiththecomputerapplicationsinmanufacturing．Thiscoupleswiththeadventofhigh－resolu鄄tiongraphics熏high－speedcomputing熏anduserintegrationdevices鸦virtualmanufacturinghasemergedasamajornewtechnologyinrecentyears眼２演．Theimpactforthechangeisparticularlypromin…     

Peptoid Efficacy against Polymicrobial Biofilms Determined by Using Propidium Monoazide‐Modified Quantitative PCR

Biofilms containing Candida albicans are responsible for a wide variety of clinical infections. The protective effects of the biofilm matrix, the low metabolic activity of microorganisms within a biofilm and their high mutation rate, significantly enhance the resistance of biofilms to conventional antimicrobial treatments. Peptoids are peptide‐mimics that share many features of host defence antimicrobial peptides but have increased resistance to proteases and therefore have better stability in vivo. The activity of a library of peptoids was tested against monospecies and polymicrobial bacterial/fungal biofilms. Selected peptoids showed significant bactericidal and fungicidal activity against the polymicrobial biofilms. This coupled with low cytotoxicity suggests that peptoids could offer a new option for the treatment of clinically relevant polymicrobial infections.