Plasma treatment constitutes an efficient method for chemical-free disinfection.A spray-based system for dispensing plasma-activated aerosols onto surfaces would facilitate disinfection of complex and/or hidden surfac...
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Plasma treatment constitutes an efficient method for chemical-free disinfection.A spray-based system for dispensing plasma-activated aerosols onto surfaces would facilitate disinfection of complex and/or hidden surfaces inaccessible to direct line-of-sight(for example,UV)*** complexity and size of current plasma generators(for example,plasma jet and cometary plasma systems)-which prohibit portable operation,together with the short plasma lifetimes,necessitate a miniaturized in situ technique in which a source can be simultaneously activated and administered on-demand onto ***,we demonstrate this possibility by combining two nanoscale technologies for plasma and aerosol generation into an integrated device that is sufficiently small and *** is generated on a carpet of zinc oxide nanorods comprising a nanoneedle ensemble,which when raised to a high electric potential,constitutes a massive point charge array with near-singular electric fields to effect atmospheric *** plasma is then used to activate water transported through an underlying capillary wick,that is subsequently aerosolized under MHz-order surface acoustic *** show that the system,besides being amenable to miniaturization and hence integration into a chipscale device,leads to a considerable improvement in plasma-activation over its macroscale cometary discharge predecessor,with up to 20%and 127%higher hydrogen peroxide and nitrite ion concentrations that are respectively generated in the plasma-activated ***,in turn,leads to a 67%reduction in the disinfection time to achieve 95%bacterial load reduction,therefore demonstrating the potential of the technology as an efficient portable platform for on-demand field-use surface disinfection.
In September 2021,the world’s most powerful high-temperature superconducting magnet passed its first test,generating a 20 T magnetic field during a 5 h trial[1].The 3 m tall,9000 kg device(Fig.1)is the centerpiece of...
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In September 2021,the world’s most powerful high-temperature superconducting magnet passed its first test,generating a 20 T magnetic field during a 5 h trial[1].The 3 m tall,9000 kg device(Fig.1)is the centerpiece of an ambitious plan by the start-up Commonwealth Fusion Systems,headquartered in Cambridge,MA,USA,to build a fusion reactor that produces more energy than it requires to stimulate and sustain its nuclear reactions[2,3].None of the experimental fusion approaches that scientists have tested has come close to that *** the multi-billion USD International Thermonuclear Experimental Reactor(ITER),the massive project sponsored by 35 countries that is under construction in southern France(Fig.2),is not projected to pass the breakeven point until the mid-2030s at the earliest[2,4].But Commonwealth Fusion Systems aims to have a pilot plant operating by 2025.
This study investigates the geological background of the August 7-8, 2010 Zhouqu debris flows in the northwestern Chinese province of Gansu, and possible future occurrence of such hazards in the peri-Tibetan Plateau (...
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This study investigates the geological background of the August 7-8, 2010 Zhouqu debris flows in the northwestern Chinese province of Gansu, and possible future occurrence of such hazards in the peri-Tibetan Plateau (TP) regions. Debris flows are a more predictable type of landslide because of its strong correlation with extreme precipitation. However, two factors affecting the frequency and magnitude of debris flows: very fine scale precipitation and degree of fracture of bedrock, both defy direct observations. Annual mean Net Primary production (NPP) is used as a surrogate for regional precipitation with patchiness filtered out, and gravity satellite measured regional mass changes as an indication of bedrock cracking, through the groundwater as the nexus.?The GRACE measurements indicate a region (to the north east of TP) of persistent mass gain (started well before the 2008 Wenchuan earthquake), likely due to increased groundwater percolation. While in the neighboring agricultural region further to the north east, there are signal of decreased fossil water reservoir. The imposed stress fields by large scale increase/decrease groundwater may contribute to future geological instability of this region. Zhouqu locates right on the saddle of the gravity field anomaly. The region surrounding the Bay of Bangle (to the southeast of TP) has a similar situation. To investigate future changes in extreme precipitation, the other key player for debris flows, the “pseudo-climate change” experiments of a weather model forced by climate model provided perturbations on the thermal fields are performed and endangered locations are identified. In the future warmer climate, extreme precipitation will be more severe and debris will be more frequent and severe.
Along with its familiar impact craters,the surface of the Moon sports numerous pale whorls and streaks known as lunar swirls[1].Likened to the pattern produced when someone pours cream into a cup of black coffee [2],t...
Along with its familiar impact craters,the surface of the Moon sports numerous pale whorls and streaks known as lunar swirls[1].Likened to the pattern produced when someone pours cream into a cup of black coffee [2],the swirls can extend for more than50 km and have puzzled researchers for centuries [3].Adding to their mystery,the features are associated with regions of magnetized rocks,an unusual attribute because the Moon lacks a magnetic field [3].Researchers do not know how the swirls are related to the magnetic fields or how they formed."They are enigmatic,"said David Blewett,a planetary geologist at the Johns Hopkins Applied Physics Laboratory in Laurel,MD,USA.
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