We report the growth of a halide-based double perovskite, Cs 2 Na x Ag 1Àx InCl 6 :y%Mn, via a facile hydrothermal reaction at 180 8C. Through a co-doping strategy of both Na + and Mn 2+ , the as-prepared crystals exhibited a red afterglow featuring a high color purity (ca. 100 %) and a long duration time (> 5400 s), three orders of magnitude longer than those solution-processed organic afterglow crystals. The energy transfer (ET) process between self-trapped excitons (STE) and activators was investigated through time-resolved spectroscopy, which suggested an ET efficiency up to 41 %. Importantly, the nominal concentration of dopants, especially in the case of Na + , was found a useful tool to control both energy level and number distribution of traps. Cryogenic afterglow measurements suggested that the afterglow phenomenon was likely governed by thermal-activated exciton diffusion and electron tunneling process.

The pandemic of COVID-19 has brought great challenges to the development of the world economy and has an unprecedented and inevitable impact on the logistics industry connecting various economic activities. In the context of the gradual alleviation of the COVID-19 outbreak in China, we observed five impacts on China's logistics industry, which are sharp drop in logistics demand, shortage of transportation capacity, disruption of logistics network, change of service mode, and increase in operating costs and number of lossmaking enterprises. When this invited paper was written, the outbreak in China has been effectively under controlled. In the post-COVID-19 era, under the three driving forces (i.e. the market, technology and policy), China's logistics industry will develop rapidly, leading to significant changes in five aspects: logistics demand, logistics supply, logistics infrastructure, logistics informatisation, and logistics industry development. The authors of this invited paper have been actively involved in the development of China's logistics industry in various capacities, governmental and non-governmental as well as in academia, and participated in a range of studies on the development trends, plans and policies of China's logistics industry. The authors have a profound understanding of the latest situation in the China's logistics industry and government initiatives.

We report an up-conversion charging (UCC) technique, which offers a new way to study persistent luminescence and utilize persistent phosphors

PurposeThis study explores the influencing factors of smart logistics ecological chain's (SLEC's) organizational collaboration and designs a corresponding conceptual framework.Design/methodology/approachThe multi-case study is applied to this paper. Specifically, this study is a combination of exploratory and explanatory case studies.FindingsThe findings are threefold. First, empowerment capability and the information-sharing level are unique factors that affect SLEC's organizational collaboration. Second, greater empowerment capability stimulates the increase of information-sharing level. Third, emerging digital technology, personalized demand and peer competition affect the degree of SLEC's organizational collaboration through an intermediary variable – empowerment capability. Specifically, the emerging digital technology application and peer competition degrees have positive effects on empowerment capability, while the demand personalization degree negatively (positively) affects empowerment capability in the short (long) term.Originality/valueAs an important part of supply chain performance, organizational collaboration is receiving more attention. However, in the smart economy context, no theoretical framework exists for analyzing factors that affect the organizational collaboration degree of SLEC. This study fills this gap.

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In recent years, international research on the toxicity of the heavy metal, antimony, has gradually changed focus from early medical and pharmacological toxicology to environmental toxicology and ecotoxicology. However, little research has been conducted for sources identification and risk management of heavy metals pollution by long-term antimony mining activities. In this study, a large number of investigations were conducted on the temporal and spatial distribution of antimony and related heavy metal contaminants (lead, zinc, and arsenic), as well as on the exposure risks for the population for the Yuxi river basin in the Hunan province, China. The scope of the investigations included mine water, waste rock, tailings, agricultural soil, surface water, river sediments, and groundwater sources of drinking water. Health and ecological risks from exposure to heavy metal pollution were evaluated. The main pollution sources of heavy metals in the Yuxi River basin were analyzed. Remediation programs and risk management strategies for heavy metal pollution were consequently proposed. This article provides a scientific basis for the risk assessment and management of heavy metal pollution caused by antimony basin ore mining.

Event cameras, which are asynchronous bio-inspired vision sensors, have shown great potential in a variety of situations, such as fast motion and low illumination scenes. However, most of the event-based object tracking methods are designed for scenarios with untextured objects and uncluttered backgrounds. There are few event-based object tracking methods that support bounding box-based object tracking. The main idea behind this work is to propose an asynchronous Event-based Tracking-by-Detection (ETD) method for generic bounding box-based object tracking. To achieve this goal, we present an Adaptive Time-Surface with Linear Time Decay (AT-SLTD) event-to-frame conversion algorithm, which asynchronously and effectively warps the spatio-temporal information of asynchronous retinal events to a sequence of ATSLTD frames with clear object contours. We feed the sequence of ATSLTD frames to the proposed ETD method to perform accurate and efficient object tracking, which leverages the high temporal resolution property of event cameras. We compare the proposed ETD method with seven popular object tracking methods, that are based on conventional cameras or event cameras, and two variants of ETD. The experimental results show the superiority of the proposed ETD method in handling various challenging environments.