Although the application of internal insulation to existing perimeter walls poses significant challenges in terms of building physics and loss of habitable space, it is sometimes an inevitable choice because of practical or legislative constraints. Innovative solutions are then required to deliver satisfying performances and reduce nuisance to inhabitants of residential buildings in case they are going to remain in their flats during the retrofit works. Three systems for inner thermal retrofitting purposes have been designed and produced as prototypes. Two of them are composed by silica aerogel containing fibrous material: the first one is a rigid flat laminated panel, the second one is a rollable solution with a fabric finishing layer. The third insulating system is a perlite based board with a hydrophobic layer. All the materials composing the retrofit solutions have been characterized by means of laboratory tests in order to measure their main hygrothermal properties. In fact, some parameters are fundamental for determining the hygrothermal performance of the composite systems: thermal conductivity, at dry and wet state (moisture dependant), water vapour diffusion resistance factor, hygroscopic sorption at isotherm condition and water absorption coefficient. All those measured data were necessary for optimizing the solutions, guaranteeing energy efficiency and vapour open layers to systems that are intended for installation on existing walls.
Abstract. Based on data recorded by the French DEMETER satellite, plasma perturbations have been analyzed before the Wenchuan 8.0 earthquake which occurred on 12 May 2008. Using the revisited orbits, the seasonal variations of the O+ density at daytime and nighttime were obtained respectively. There mainly exist two kinds of shapes of O+ density, with peak values in the Northern Hemisphere during May to September and reversely in the Southern Hemisphere during other months. Analysis on local daytime O+ density showed that it reached its lowest values 3 days prior to the earthquake, i.e. on 9 May. With studies in more than 3 month time series and comparison with those in 2006 and 2007, it was found that the significant decrease of the O+ density on 9 May 2008 was different from the trend variations of 2007 and 2006 both with relatively higher O+ density in May. In addition, the ion density and temperature was also analyzed before the earthquake at local nighttime. They showed smallest value in O+ density and fast and short-term variations in ion temperature on 9 May above the epicenter area. All these plasma anomalies may be related to the Wenchuan earthquake. Finally, using our results and those published in other papers, the possible mechanisms of these ionospheric anomalies were discussed.
Abstract. During the DEMETER operating period in 2004–2010, many strong earthquakes took place in the world. 69 strong earthquakes with a magnitude above 7.0 during January 2005 to February 2010 were collected and analysed. The orbits, recorded in local nighttime by satellite, were chosen by a distance of 2000 km to the epicentres during the 9 days around these earthquakes, with 7 days before and 1 day after. The anomaly is defined when the disturbances in the electric field PSD increased to at least 1 order of magnitude relative to the normal median level about 10−2μV2/m2/Hz at 19.5–250 Hz frequency band, and the starting point of perturbations not exceeding 10° relsupative to the epicentral latitude. Among the 69 earthquakes, it is shown that electrostatic perturbations were detected at ULF-ultra low frequency and ELF-extremely low frequency band before the 32 earthquakes, nearly 46%. Furthermore, we extended the searching scale of these perturbations to the globe, and it can be found that before some earthquakes, the electrostatic anomalies were distributed in a much larger area a few days before, and then they concentrated to the closest orbit when the earthquake would happen one day or a few hours later, which reflects the spatial developing feature during the seismic preparation process. The results in this paper contribute to a better description of the electromagnetic (EM) disturbances at an altitude of 660–710 km in the ionosphere that can help towards a further understanding of the lithosphere-atmosphere-ionosphere (LAI) coupling mechanism.
The ongoing coronavirus disease 2019 (COVID-19) outbreak, emerged in Wuhan, China in the end of 2019, has claimed more than 2600 lives as of 24 February 2020 and posed a huge threat to global public health. The Chinese government has implemented control measures including setting up special hospitals and travel restriction to mitigate the spread. We propose conceptual models for the COVID-19 outbreak in Wuhan with the consideration of individual behavioural reaction and governmental actions, e.g., holiday extension, travel restriction, hospitalisation and quarantine. We employe the estimates of these two key components from the 1918 influenza pandemic in London, United Kingdom, incorporated zoonotic introductions and the emigration, and then compute future trends and the reporting ratio. The model is concise in structure, and it successfully captures the course of the COVID-19 outbreak, and thus sheds light on understanding the trends of the outbreak. ; Department of Applied Mathematics ; School of Nursing ; 202003 bcwh ; published_final
Hierarchical 1D carbon structures are attractive due to their mechanical, chemical and electrochemical properties however the synthesis of these materials can be costly and complicated. Here, through the combination of inexpensive acetylacetonate salts of Ni, Co and Fe with a solution of polyacrylonitrile (PAN), self-assembling carbon-metal fabrics (CMFs) containing unique 1D hierarchical structures can be created via easy and low-cost heat treatment without the need for costly catalyst deposition nor a dangerous hydrocarbon atmosphere. Microscopic and spectroscopic measurements show that the CMFs form through the decomposition and exsolution of metal nanoparticle domains which then catalyze the formation of carbon nanotubes through the decomposition by-products of the PAN. These weakly bound nanoparticles form structures similar to trichomes found in plants, with a combination of base-growth, tip-growth and peapod-like structures, where the metal domain exhibits a core(graphitic)-shell(disorder) carbon coating where the thickness is in-line with the metal-carbon binding energy. These CMFs were used as a cathode in a flexible zinc-air battery which exhibited superior performance to pure electrospun carbon fibers, with their metallic nanoparticle domains acting as bifunctional catalysts. This work therefore unlocks a potentially new category of composite metal-carbon fiber based structures for energy storage applications and beyond. ; This work was kindly supported by the EPSRC energy storage for low carbon grids project (EP/K002252/1), the EPSRC Joint UK-India Clean Energy Centre (JUICE) (EP/P003605/1), the EPSRC Multi-Scale Modelling project (EP/S003053/1), and the Innovate UK for Advanced Battery Lifetime Extension (ABLE) project, Soft Science Research Project of Guangdong Province (No. 2017B030301013), Shenzhen Science and Technology Research Grant (ZDSYS201707281026184). Swansea University College of Engineering Advanced Imaging of Materials (AIM) Facility, which was funded by the EPSRC (EP/M028267/1), the European Regional Development Fund through the Welsh Government (80708), and the Ser Solar project via Welsh Government. CG acknowledges The Royal Society of London for an URF.
Using the data sets taken at center-of-mass energies above 4 GeV by the BESIII detector at the BEPCII storage ring, we search for the reaction e(+)e(-) -> gamma(ISR) X(3872) -> gamma(ISR)pi(+)pi(-) J/psi via the Initial State Radiation technique. The production of a resonance with quantum numbers J(PC) = 1(++) such as the X(3872) via single photon e(+)e(-) annihilation is forbidden, but is allowed by a next-to-leading order box diagram. We do not observe a significant signal of X(3872), and therefore give an upper limit for the electronic width times the branching fraction Gamma B-X(3872)(ee)(X(3872) -> pi(+)pi(-) J/psi) < 0.13 eVat the 90% confidence level. This measurement improves upon existing limits by a factor of 46. Using the same final state, we also measure the electronic width of the psi(3686) to be Gamma(psi)(ee)(3686) ee = 2213 +/- 18(stat) +/- 99(sys) eV. ; Funding: The BESIII collaboration thanks the staff of BEPCII and the IHEP computing center for their strong support. This work is supported in part by the National Key Basic Research Program of China under Contract No. 2015CB856700; National Natural Science Foundation of China (NSFC) under Contract Nos. 11125525, 11235011, 11322544, 11335008, 11425524; the Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program; Joint Large-Scale Scientific Facility Funds of the NSFC and CAS under Contract Nos. 11179007, U1232201, U1332201; CAS under Contract Nos. KJCX2-YW-N29, KJCX2-YW-N45; 100 Talents Program of CAS; INPAC and Shanghai Key Laboratory for Particle Physics and Cosmology; German Research Foundation DFG under Contract No. CRC-1044; Seventh Framework Programme of the European Union under Marie Curie International Incoming Fellowship Grant Agreement No. 627240; Istituto Nazionale di Fisica Nucleare, Italy; Ministry of Development of Turkey under Contract No. DPT2006K-120470; Russian Foundation for Basic Research under Contract No. 14-07-91152; U.S. Department of Energy under Contract Nos. DE-FG02-04ER41291, DE-FG02-05ER41374, DE-FG02-94ER40823, DESC0010118; U.S. National Science Foundation; University of Groningen (RuG) and the Helmholtzzentrum fur Schwerionenforschung (GSI), Darmstadt; WCU Program of National Research Foundation of Korea under Contract No. R32-2008-000-10155-0.
Background: The COVID-19 pandemic has disrupted routine hospital services globally. This study estimated the total number of adult elective operations that would be cancelled worldwide during the 12 weeks of peak disruption due to COVID-19. Methods: A global expert response study was conducted to elicit projections for the proportion of elective surgery that would be cancelled or postponed during the 12 weeks of peak disruption. A Bayesian β-regression model was used to estimate 12-week cancellation rates for 190 countries. Elective surgical case-mix data, stratified by specialty and indication (surgery for cancer versus benign disease), were determined. This case mix was applied to country-level surgical volumes. The 12-week cancellation rates were then applied to these figures to calculate the total number of cancelled operations. Results: The best estimate was that 28 404 603 operations would be cancelled or postponed during the peak 12 weeks of disruption due to COVID-19 (2 367 050 operations per week). Most would be operations for benign disease (90·2 per cent, 25 638 922 of 28 404 603). The overall 12-week cancellation rate would be 72·3 per cent. Globally, 81·7 per cent of operations for benign conditions (25 638 922 of 31 378 062), 37·7 per cent of cancer operations (2 324 070 of 6 162 311) and 25·4 per cent of elective caesarean sections (441 611 of 1 735 483) would be cancelled or postponed. If countries increased their normal surgical volume by 20 per cent after the pandemic, it would take a median of 45 weeks to clear the backlog of operations resulting from COVID-19 disruption. Conclusion: A very large number of operations will be cancelled or postponed owing to disruption caused by COVID-19. Governments should mitigate against this major burden on patients by developing recovery plans and implementing strategies to restore surgical activity safely.