Suchergebnisse

AbstractSouth Korea has among the highest rates of suicide in the world, and previous research suggests that suicide frequency increases with anomalously high temperatures, possibly as a result of increased sunshine. However, it is unclear whether this temperature–suicide association exists throughout the entire year. Using distributed lag nonlinear modeling, which effectively controls for nonlinear and delayed effects, we examine temperature–suicide associations for both a warm season (April–September) and a cool season (October–March) for three cities across South Korea: Seoul, Daegu, and Busan. We find consistent, statistically significant, mostly linear relationships between relative risk of suicide and daily temperature in the cool season but few associations in the warm season. This seasonal signal of statistically significant temperature–suicide associations only in the cool season exists among all age segments, but especially for those 35 and older, along with both males and females. We further use distributed lag nonlinear modeling to examine cloud cover–suicide associations and find few significant relationships. This result suggests that that high daily temperatures in the cool season, and not exposure to sun, are responsible for the strong temperature–suicide associations found in South Korea.

For the first time the paper determines thermophysical properties (specific heat capacity, thermal diffusivity, and heat conductivity) of the full-scale corium of the fast energy nuclear reactor within the temperature range from ~30°С to ~400°С. Obtained data are to be used in temperature fields calculations during modeling the processes of corium melt retention inside of the fast reactor vessel.

The radiative recombination coefficient B(T) of intrinsic crystalline silicon is determined as a function of temperature over the temperature range 77–300 K. We observe that B(T) decreases as a function of temperature and we compare our results to previously published contradictory data from the literature. The radiative recombination coefficient is calculated from the absorption coefficient for band-to-band transitions, which we determine at different temperatures from photoluminescencespectra measured on planar high resistivity float zone silicon wafers. Photoluminescencespectra could be detected over a large range of more than five orders of magnitude, which allowed us to determine extremely low values of the absorption coefficient in the spectral range where absorption processes are accompanied by the simultaneous absorption of up to four phonons. ; The Centre of Excellence for Advanced Silicon Photovoltaics and Photonics is supported under the Australian Research Council's Centres of Excellence Scheme. One author (T.T.) would like to thank the Alexander von Humboldt foundation for a Feodor Lynen-Scholarship while another (M.A.G.) acknowledges the award of an Australian Government Federation Fellowship.

The radiative recombination coefficient B(T) of intrinsic crystalline silicon is determined as a function of temperature over the temperature range 77–300 K. We observe that B(T) decreases as a function of temperature and we compare our results to previously published contradictory data from the literature. The radiative recombination coefficient is calculated from the absorption coefficient for band-to-band transitions, which we determine at different temperatures from photoluminescencespectra measured on planar high resistivity float zone silicon wafers. Photoluminescencespectra could be detected over a large range of more than five orders of magnitude, which allowed us to determine extremely low values of the absorption coefficient in the spectral range where absorption processes are accompanied by the simultaneous absorption of up to four phonons. ; The Centre of Excellence for Advanced Silicon Photovoltaics and Photonics is supported under the Australian Research Council's Centres of Excellence Scheme. One author (T.T.) would like to thank the Alexander von Humboldt foundation for a Feodor Lynen-Scholarship while another (M.A.G.) acknowledges the award of an Australian Government Federation Fellowship.

7 pags., 7 figs., 1 tab. ; We applied the recently developed Generalized Langevin equation (GLE) approach for dielectric response of liquids and glasses to link the vibrational density of states (VDOS) to the dielectric response of a model orientational glass. The dielectric functions calculated based on the GLE, with VDOS obtained in experiments and simulations as input, are compared with experimental data for the paradigmatic case of 2-Adamantanone at various temperatures. The memory function is related to the integral of the VDOS times a spectral coupling function γ(ωp), which tells the degree of dynamical coupling between molecular degrees of freedom at different eigenfrequencies. With respect to previous empirical fittings, the GLE-based fitting reveals a broader temperature range over which the secondary relaxation is active. Furthermore, the theoretical analysis provides clear evidence of secondary relaxation being localized within the THz (0.5-1 THz) range of eigenfrequencies, and thus not too far from the low-energy modes involved in α relaxation. In the same THz region, the same material displays a crowding of low-energy optical modes that may be related to the secondary relaxation. ; B.C. acknowledges the financial support of CSCCambridge Scholarship. J.L.T. acknowledges MINECO (No. FIS2017-82625-P) and the Catalan government (No. SGR2017-042) for financial support.

Near room-temperature magnetic and magnetocaloric properties of the compounds Pr0.63-xHoxSr0.37MnO3 (x=0, 0.05) were investigated. The parent compound Pr0.63Sr0.37MnO3 has a large magnetocaloric effect around its Curie temperatures of about 300 K. Partially replacing of Pr3+ ions with Ho3+ ions in Pr0.63Sr0.37MnO3 gives rise to disorder which leads to the decrease of the Curie temperature without a significant reduction of the magnetocaloric effect. The samples were prepared by solid state reaction and were found to be single phase by x-ray diffraction. The magnetic measurements reveal paramagnetic to ferromagnetic second order phase transitions. For the sample with x = 0, the magnetic entropy change |ΔSM| was in the range from 1.91 J/kg٠K (RCP = 42 J/kg) for μ0 ΔH = 1 T to 4.86 J/kg٠K (RCP = 184 J/kg) for μ0 ΔH = 4 T. For the sample with x = 0.05, the magnetic entropy change |ΔSM| was in the range from 1.61 J/kg٠K (RCP = 57.9 J/kg) for μ0 ΔH = 1 T to 4.38 J/kg٠K (RCP = 236 J/kg) for μ0 ΔH = 4 T and Tc = 216 K. These values recommend these materials to be potential candidates to be used in near room-temperature refrigeration applications.

Abstract
Thermal comfort is linked to our health, well-being, and productivity. The thermal environment is one of the main factors that influence thermal comfort and, consequently, the productivity of occupants inside buildings. Meanwhile, behavioural adaptation is well known to be the most critical contributor to the adaptive thermal comfort model. This systematic review aims to provide evidence regarding indoor thermal comfort temperature and related behavioural adaptation. Studies published between 2010 and 2022 examining indoor thermal comfort temperature and behavioural adaptations were considered. In this review, the indoor thermal comfort temperature ranges from 15.0 to 33.8 °C. The thermal comfort temperature range varied depending on several factors, such as climatic features, ventilation mode, type of buildings, and age of the study population. Elderly and younger children have distinctive thermal acceptability. Clothing adjustment, fan usage, AC usage, and open window were the most common adaptive behaviour performed. Evidence shows that behavioural adaptations were also influenced by climatic features, ventilation mode, type of buildings, and age of the study population. Building designs should incorporate all factors that affect the thermal comfort of the occupants. Awareness of practical behavioural adaptations is crucial to ensure occupants' optimal thermal comfort.

The European Union and the United States of America are fostering electrification of road transport as a means for achieving ambitious policy targets set to tackle air pollution and climate change. In 2011, the US DoE Argonne National Laboratory (ANL) and the EC Joint Research Centre (JRC) established a collaborative work programme for pre-normative research on interoperability of smart grids and electric vehicles, as well as fuel/energy efficiency of hybrid- and full-electric vehicles. The present paper reports about a joint experimental campaign on a plug-in range extended vehicle (REEV) carried out at ANL's Advanced Powertrain Research Facility (APRF) and at JRC's Vehicle Electric Laboratory (VeLA 8). The vehicle was tested on the two roller benches against EU and US legislative cycles, at representative ambient temperatures varying between -30°C and 50°C, in order to investigate the impact of extreme ambient conditions on fuel and energy efficiency.

Range performance of a thermal imaging system is characterised by the prevailing atmospheric condition present at that time. There are two dominant parameters that limit the range performance of any thermal imaging systems i.e. ambient temperature and relative humidity. In the present work, comparative study of acquisition range performance of thermal imaging system operating in LWIR and MWIR spectral bands has been presented as a function of absolute humidity (AH) which is responsible for attenuation of IR radiation due to water vapour molecules present in path length. Presentation of acquisition range as function of AH leads to a single range performance table/graph for thermal imaging system under consideration for predefined visibility (V), target size, ambient temperature (T), target to background temperature difference (ΔT) and relative humidity (RH). This table/graph can be used to predict detection, recognition and identification ranges for any set of combination of air temperature (T) and relative humidity (RH). The approach presented in this paper is versatile and has been illustrated through comparative performance analysis of LWIR and MWIR thermal imaging systems based on 640X512 staring focal plane array (FPA) having identical design parameters in terms of resolution (IFOV). It has been shown that MWIR performance is superior to LWIR beyond a crossover value of AH(T) even though MRTD of MWIR sensor is inferior to that of LWIR sensor at all spatial frequencies. Study has been carried out both for clear atmosphere and hazy conditions.

Based on the results of the work performed, the nature of the phase distribution in the resulting material, structural and morphological differences between the layered metal-ceramic and ceramic structures were established. The temperature range of zirconium nitride synthesis from 1500 to 2400° C is investigated, and the possibility of successful synthesis of nitride ceramics by the indicated method at temperatures significantly exceeding the melting point of the metal is shown.

Current particle number related vehicle emission legislation is limited down to 23 nm. The rationale behind the 23 nm cut-off size is based on the avoidance of significant uncertainties created during sampling and measuring sub-23 nm solid particles. Difficulties in introducing a robust measurement protocol in this particle size range led regulation authorities to ignore their contribution to ambient pollution. However, the sub-23 nm particles draw high attention since current gasoline engines emit almost equal fraction of sub- and above- 23 nm particles, while diesel engines with after-treatment devices may also emit such ultrafine particles under certain conditions (i.e. regeneration of particulate filters) (Giechaskiel and Martini, 2014). Number concentration measurement certification methods rely exclusively on a protocol defined from the Particle Measurement Programme (PMP) working group. Accordingly, the raw exhaust is driven to a full flow dilution tunnel and subsequently to a Volatile Particle Remover (VPR) to remove possible volatile and semi-volatile material that condenses on solid particles or creates a separate nucleation mode. The VPR consists of a hot and a cold dilution stage while an evaporation tube or a catalytic stripper (CS) are inserted between these two dilution stages. One of the problems identified with the standard sampling procedures is the potential formation of particles in the sub-23 nm region, the so-called artefacts, as well as the high particle losses due to diffusion. To overcome the above-mentioned uncertainties we investigate a novel approach for sub-23 nm measurements that necessitates a single hot dilution stage and a high-temperature size classification measurement with the Advanced Half-Mini Differential Mobility Analyzer (HM-DMA). The Advanced HM-DMA system is a supercritical DMA, with a 2 cm working section, able to classify aerosol particles in the mobility size range 4 – 30 nm with high resolution and fast spectrum acquisition (de la Mora, 2017). Due to recent ...

WTe2 and MoTe2 single crystals were grown, some of them were quenched, and the following properties were studied: electroresistivity in the temperature range from 1.8 to 300 K, magnetoresistivity at temperatures from 1.8 to 300 K in magnetic fields of up to 9 T. On the one hand, quenching leads to dramatic changes in the behaviour and value of the electroresistivity of MoTe2; the type of the electroresistivity changes from "semiconductor"to "metallic", and the electroresistivity values of MoTe2 before and after quenching differ by 8 orders of magnitude (!) at low temperatures. On the other hand, quenching is shown not to lead to significant changes in the behaviour and value of the electroresistivity of WTe2. A relatively small increase in the electroresistivity of quenched WTe2 at low temperatures can be associated with the scattering of current carriers by structural defects. The magnetoresistivity of MoTe2 increases from 7 to 16% in a field of 9 T at a temperature of 12 K as a result of quenching. The magnetoresistivity of WTe2 is shown to reach ∼1700% in a field of 9 T at 2 K. The behaviour of the magnetoresistivity of non-quenched samples is typical for compensated conductors with a closed Fermi surface. © 2021 Author(s). ; The research was carried out within the state assignment of Ministry of Education and Science of the Russian Federation (theme "Spin", No. AAAA-A18-118020290104-2), supported in part by RFBR (Project No. 20-32-90069) and the Government of the Russian Federation (Decree No. 211, Contract No. 02.A03.21.0006).

The investigation results of the annealing influence (Тann = 300–800 ºС) on the minority charge currier lifetime tP in the n-base of p-n-structures, manufactured on the base of neutron transmutation doped silicon (NTD) КОФ300, irradiated at room temperature by different fluences (F = 1 · 1014 – 3 · 1016 cm–2) of electrons with the energy of Еe = 4 MeV are presented. It is established that at low electron fluences (F = 1 · 1014 cm–2), the annealing of minority charge currier lifetime tP in the n-base of p-n-structures occurs in two stages: the first – 320–400 ºС and the second – 550–650 ºС. At higher electron fluences (F = 5 · 1015–2 · 1016 cm–2), three annealing stages occur: the first – 400–450 ºС, the second – 520–650 ºС and the third – 710–770 ºС. At this, the structure barrier capacitance C dependences on Тann at high electron fluences show the geometry capacitance up to the annealing temperatures Тann = 400 ºС. In the annealing temperature range of Тann = 420–570 ºС, the increase in С with maximum is seen at Тann = 480 ºС and a subsequent decrease in the geometry capacitance is seen in the annealing temperature range of Тann = 600–670 ºС, and then again the increase in С occurs in the annealing temperature range of Тann = 720–770 ºС reaching the С values corresponding to those of the non-irradiated samples in the annealing temperature range of Тann = 770–800 ºС. The analysis of the DLTS-spectra of the investigated structures has allowed establishing the formation in the annealing process of the deep acceptor level ЕС – 0.68 eV at Тann > 400 ºС, the deep donor level ЕС – 0.32 eV in the annealing temperature range of Тann = 420–570 ºС and the deep acceptor level ЕС – 0.53 eV at Тann > 700 ºС, which satisfactorily explains the dependences of t P and С on Тann obtained in this paper.