• Energy Research
• natural sciences close
• GB close
• EU close
• BE close
• English close

Owing to their high luminous efficiency and tunable emission in both red light and far-red light regions, Mn4+ ion-activated phosphors have appealed significant interest in photoelectric and energy conversion devices such as white light emitting diode (W-LED), plant cultivation LED, and temperature thermometer. Up to now, Mn4+ has been widely introduced into the lattices of various inorganic hosts for brightly red-emitting phosphors. However, how to correlate the structure-activity relationship between host framework, luminescence property, and photoelectric device is urgently demanded. In this review, we thoroughly summarize the recent advances of Mn4+ doped phosphors. Meanwhile, several strategies like co-doping and defect passivation for improving Mn4+ emission are also discussed. Most importantly, the relationship between the protocols for tailoring the structures of Mn4+ doped phosphors, increased luminescence performance, and the targeted devices with efficient photoelectric and energy conversion efficiency is deeply correlated. Finally, the challenges and perspectives of Mn4+ doped phosphors for practical applications are anticipated. We cordially anticipate that this review can deliver a deep comprehension of not only Mn4+ luminescence mechanism but also the crystal structure tailoring strategy of phosphors, so as to spur innovative thoughts in designing advanced phosphors and deepening the applications.

With the increase in energy of the Large Hadron Collider to a centre-of-mass energy of 13 TeV for Run 2, events with dense environments, such as in the cores of high-energy jets, became a focus for new physics searches as well as measurements of the Standard Model. These environments are characterized by charged-particle separations of the order of the tracking detectors sensor granularity. Basic track quantities are compared between 3.2 fb$^{-1}$ of data collected by the ATLAS experiment and simulation of proton-proton collisions producing high-transverse-momentum jets at a centre-of-mass energy of 13 TeV. The impact of charged-particle separations and multiplicities on the track reconstruction performance is discussed. The efficiency in the cores of jets with transverse momenta between 200 GeV and 1600 GeV is quantified using a novel, data-driven, method. The method uses the energy loss, dE/dx, to identify pixel clusters originating from two charged particles. Of the charged particles creating these clusters, the measured fraction that fail to be reconstructed is $0.061 \pm 0.006 \textrm{(stat.)} \pm 0.014 \textrm{(syst.)}$ and $0.093 \pm 0.017 \textrm{(stat.)}\pm 0.021 \textrm{(syst.)}$ for jet transverse momenta of 200-400 GeV and 1400-1600 GeV, respectively. The European physical journal / C 77(10), 673 (2017). doi:10.1140/epjc/s10052-017-5225-7 Published by Springer, Berlin

Thousands of Neolithic and Bronze Age open-air rock art panels exist across the countryside in northern England. However, desecration, pollution, and other factors are threatening the survival of these iconic stone monuments. Evidence suggest that rates of panel deterioration may be increasing, although it is not clear whether this is due to local factors or wider environmental influences accelerated by environmental change. To examine this question, 18 rock art panels with varied art motifs were studied at two major panel locations at Lordenshaw and Weetwood Moor in Northumberland. A condition assessmenttool was used to first quantify the level of deterioration of each panel (called “staging”). Stage estimates then were compared statistically with 27 geochemical and physical descriptors of local environments, such as soil moisture, salinity, pH, lichen coverage, soil anions and cation levels, and panel orientation, slope, and standing height. In parallel, climate modelling was performed using UKCP09 to assess how projected climatic conditions (to 2099) might affect the environmental descriptors most correlated with elevated stone deterioration. Only two descriptors significantly correlated (P < 0.05) with increased stage: the standing height of the panel and the exchangeable cation content of the local soils, although moisture conditions also were potentially influential at some panels. Climate modelling predicts warming temperatures, more seasonally variable precipitation, and increased wind speeds, which hint stone deterioration could accelerate in the future due to increased physiochemical weathering. We recommend key panels be targeted for immediate management intervention, focusing on reducing wind exposures, improving site drainage, and potentially immobilizing soil salts.

This work, carried out at Research Centre for Industrial Crops of CREA in Rovigo, aimed at assessing the performance of a modified combine header and seed losses during late harvest of 5 hemp varieties. The renewed interest in Italy for hemp cultivation is aimed at seed production unlike the traditional cultivation aimed at fibre. However, it must face the lack of monoecious varieties suitable for Italian environment. In the case of dioecious varieties, traditionally cultivated in Italy for fibre production, the high crop height makes it difficult the mechanical harvesting with conventional combines. Similarly, the uneven height recorded in the case of imported varieties for seed production, requires adjusting continuously the height of the combine header. So, modified combine headers capable of be moved upwards and downwards by a lift have been developed. The aim is to avoid the risk of possible clogging of threshing apparatus introducing big pieces of stalks. Moreover, in this way, the stalks can be harvested separately in order to increase the income for farmers. In view of valorise the whole plant, as multipurpose crop, the right harvest time should be a trade-off between seed yield and fibre quality. Early harvesting guaranties a good fibre quality but causes also the harvest of seed not completely ripened. On the contrary delaying the harvest reduces the seed yield due to seed loss for dehiscence. In addition to losses for dehiscence prior to harvest, the trials aimed at distinguishing the loss incurred during harvest attributable both to crop disturbance by combine header and to the setting of the combine’s threshing and separation elements. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 197-200