Nonlinear dynamics of proton beams with hollow electron lens in the CERN high-luminosity LHC

The design stored beam energy in the CERN high-luminosity large hadron collider (HL-LHC) upgrade is about 700 MJ, with about 36 MJ in the beam tails, according to estimates based on scaling considerations from measurements at the LHC. Such a large amount of stored energy in the beam tails poses serious challenges on its control and safe disposal. In particular, orbit jitters can cause significant losses on primary collimators, which can lead to accidental beam dumps, magnet quenches, or even permanent damage to collimators and other accelerator elements. Thus, active control of the diffusion speed of halo particles is necessary and the use of hollow electron lenses (HELs) represents the most promising approach to handle overpopulated tails at the HL-LHC. HEL is a very powerful and advanced tool that can be used for controlled depletion of beam tails, thus enhancing the performance of beam halo collimation. For these reasons, HELs have been recently included in the HL-LHC baseline. In this paper, we present detailed beam dynamics calculations performed with the goal of defining HEL specifications and operational scenarios for HL-LHC. The prospects for effective halo control in HL-LHC are presented.

Geospatial Correlation Analysis between Air Pollution Indicators and Estimated Speed of COVID-19 Diffusion in the Lombardy Region (Italy)

Background: the Lombardy region in Italy was the first area in Europe to record an outbreak of COVID-19 and one of the most affected worldwide. As this territory is strongly polluted, it was hypothesized that pollution had a role in facilitating the diffusion of the epidemic, but results are uncertain. Aim: the paper explores the effect of air pollutants in the first spread of COVID-19 in Lombardy, with a novel geomatics approach addressing the possible confounding factors, the reliability of data, the measurement of diffusion speed, and the biasing effect of the lockdown measures. Methods and results: all municipalities were assigned to one of five possible territorial classes (TC) according to land-use and socio-economic status, and they were grouped into districts of 100,000 residents. For each district, the speed of COVID-19 diffusion was estimated from the ambulance dispatches and related to indicators of mean concentration of air pollutants over 1, 6, and 12 months, grouping districts in the same TC. Significant exponential correlations were found for ammonia (NH3) in both prevalently agricultural (R2 = 0.565) and mildly urbanized (R2 = 0.688) areas. Conclusions: this is the first study relating COVID-19 estimated speed of diffusion with indicators of exposure to NH3. As NH3 could induce oxidative stress, its role in creating a pre-existing fragility that could have facilitated SARS-CoV-2 replication and worsening of patient conditions could be speculated.

Design and development of a biotreatment of E. crassipes for the decontamination of water with Chromium (VI)

The use of cellulose materials for the adsorption of heavy metals has increased in favorable results to comply with the removal of these contaminants from water, such as the case of Chromium (VI), being one of the most dangerous heavy metals for the environment and human health. The objective of this research is to design and develop a biotreatment with dry and crushed biomass of E. crassipes for the continuous treatment of Chromium (VI), determining through mathematical modeling the Fick diffusion constant (Kf), based on this constant Fick will establish the performance of the biotreatment and the intraparticle diffusion constant (Ks). The diffusion speed (Kf) of the biomass of E. crassipes chemisorbing Cr (VI) of 0.30 cm/min, also it got the constant of the adsorption capacities (Ks) was 0.0198 s. With (Kf) it can design the treatment systems according to caudal or load greatly contaminated, calibrating the parameters how caudal, volume, or area of contact of the system of treatment. Also with (Ks) will be possible the design and modeling of a treatment system to improve the capacity of adsorptions calibrating the density of the particle and the density of the contact bed of the treatment system. Based on Fick's second law, an equation was designed to determine the reliability and performance of water treatment systems through the E. crassipes plant.

The consequences of inaction on carbon dioxide removal

Carbon dioxide removal (CDR) will be essential to meet the climate targets, so enabling its deployment at the right time will be decisive. Here, we investigate the still poorly understood implications of delaying CDR actions, focusing on integrating direct air capture and bioenergy with carbon capture and storage (DACCS and BECCS) into the European Union power mix. Under an indicative target of − 50 Gt of net CO2 by 2100, delayed CDR would cost an extra of 0.12 − 0.19 trillion EUR per year of inaction. Moreover, postponing CDR beyond mid-century would substantially reduce the removal potential to almost half (− 35.60 Gt CO2) due to the underused biomass and land resources and the maximum technology diffusion speed. The effective design of BECCS and DACCS systems calls for long-term planning starting from now and aligned with the evolving power systems. Our quantitative analysis of the consequences of inaction on CDR —with climate targets at risk and fair CDR contributions at stake —should help to break the current impasse and incentivize early actions worldwide.

All-Solid-State Proton-Based Tandem Structure Achieving Ultrafast Switching Electrochromic Windows

All-solid-state electrochromic devices (ECDs) for smart-window applications currently suffer from limited ion diffusion speed, which lead to slow coloration and bleaching processes. Here, we design an all-solid-state tandem structure with protons as diffusing species achieving an ultrafast switching ECD. We use WO3 as the electrochromic material, while poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) as the solid-state proton source to enable fast switching. This structure by itself exhibits low optical modulation (i.e., difference of on/off transmittance). We further introduce a solid polymeric electrolyte layer on top of PEDOT:PSS to form a tandem structure, which provides Na+ ions to PEDOT:PSS and pump protons there to the WO3 layer through ion exchange. Our new all-solid-state ECD features high optical modulation (>92% at 650 nm), fast response (coloration to 90% in 0.7 s and bleaching to 65% in 0.9 s and 90% in 7.1 s) and excellent stability (<10% degradation after 3000 cycles). Large-area (30×40 cm2) as well as flexible devices are fabricated to demonstrate the great potential for scaling up.

What are the main determinants of diffusion speed between academic research and industrial application? Evidence from four major clean-energy technologies

Recent evidence suggests a slowdown of economic productivity in major Western and Asian economies. One of the most convincing causes is the slowdown in research productivity in key sectors of the economy, such as low-carbon technologies. The latter trend is particularly worrying as low-carbon technologies play a critical role in keeping global warming well below the 2°C that the Paris Agreement set. We rely on a novel data science method that connects scientific articles with patented technologies. We extract the scientific publications cited in more than 600,000 clean energy technologies (wind, solar, biomass, li-ion) and investigate what determines the diffusion speed between scientific research and patented technologies. We demonstrate that the higher the quality of the scientific article (measured by citations), the lower the distance between scientists and inventors, and the higher the similarity between the content of the scientific article and the patent, the faster the diffusion between research and application. Yet, we also show that while more dissimilar content takes longer to be used in patents, the eventual impact of the patent is greater, possibly because it is more innovative. Our data also reveals that while distance appears to matter for the speed of knowledge diffusion, patents in the four low-carbon technologies on average rely on 81% of foreign sources of science, as scientific knowledge diffuses widely across the world economy. China and the United States play an outsized role as the source of scientific publications used in clean-technology patents globally. Nevertheless, while research is characterised by global spillovers, the application of such knowledge (in a patent) appears to be dominated by national teams, potentially due to greater local spillovers and secrecy issues.

Dynamics of a Delayed Interactive Model Applied to Information Dissemination in Social Networks

Reducing fake news and rumor propagation through social media may be challenging to achieve when dealing with sensible contents and communities with free access to online shared resources. Controlling rumor dissemination and promoting true news are the main techniques used to strangle false information that may result in dramatic effect on human wellbeing in an open or closed environment. In this article, we studied a predator-prey model with constant delay in both predator and prey equations and applied the proposed model to the underlying relationship between the existing rumor propagating through social media and the related authoritative information containing the truth broadcast to reduce the respective rumor negative effect on the targeted community. We showed that the proposed system was very responsive to small perturbations and exhibited complex dynamical behavior around the steady-state equilibrium when interaction occurs and delay is applied, considering the controlled situations. Numerical results suggested applying relatively small delay, which represents the ideal time to publish the related propagating rumor curative content to reduce its diffusion speed and promote the truth.

Numerical Analysis of the Hydrogen Dispersion Behavior in Different Directions in a Naturally Ventilated Space

Studies on hydrogen leakage have mainly focused on the influences of location and geometrical configuration on the distribution of the hydrogen in various spaces. The present study developed a simplified model for the leakage diffusion of hydrogen in an enclosed cuboid space with two vents, at the top and at the bottom, respectively. The effect of different leakage positions on the diffusion of the hydrogen was analyzed. The results showed that when hydrogen diffused vertically from the bottom to the top of the space, the farther the leakage position was from the vent on the side wall, the more hydrogen accumulated. When the hydrogen leaked in the vertical direction from the floor, the distance between the leakage position and the bottom vent had little effect on the horizontal diffusion speed of the hydrogen at the top of the space. The diffusion speed for the leakage in the horizontal direction was faster than that in the vertical direction. When the hydrogen leaked in the horizontal direction from the side wall, the height of the leakage had little effect on the horizontal diffusion speed of the hydrogen at the top of the space. Stratification occurred for models set up in the present study whenever the envelope of 1% mole fraction, or 4% mole fraction, of hydrogen extended to the whole ceiling.

Laboratory simulation on drifting of hazardous chemical substance

The continuously increase of hazardous chemicals transportation leads to a high risk of chemicals leakage. Researches on drifting of chemical substances are of vital importance in damage reducing. Laboratory simulation on drifting of hazardous chemical substance carried out inside a wave tank at the Shandong Provincial Key Laboratory. Different environmental conditions (wind, wave, etc.) were simulated in the wave tank to find out the influence of these factors on substance drifting and diffusion. To identify the difference between hazardous substance, floating ball and dyed petroleum oil were used to simulate solid and liquid floating hazardous chemical substance. The result revealed that wave can improve diffusion, the diffusion speed varies with wave height. Wind can drive surface substance, the drifting coefficient ranges from 2.1% to 3.0%, while liquid drifting coefficient is relatively larger. The laboratory results provide a basis for the study on the drifting and diffusion of hazardous chemicals at sea. Meanwhile, the coefficient could be applied as a correction in numerical models to improve prediction accuracy.

Study on migration and change of petroleum pollutants in soil and pollution evaluation with data mining technology

To study the migration and variation rule of petroleum pollutants in soil and evaluate the soil condition, the field investigation is carried out in a refinery in Yunnan Province and the relevant data are collected. Then, soil sampling and leaching experiments are carried out on the land in the refinery. Finally, the experimental data are sorted out. The experimental results show that the pollution of surface soil in refinery is the most serious. Because of the adsorb-ability of the soil, the content of petroleum pollutants in the deep soil is less. The results of leaching experiments show that the diffusion process of petroleum pollutants is greatly affected by random factors in horizontal diffusion. In the vertical direction, the depth of soil will reduce the diffusion speed of petroleum pollutants. This exploration provides a reference for the study of the migration and variation rule of petroleum pollutants in soil.