Photothermal therapy at the NIR‐II biowindow (1000–1350 nm) is drawing increasing interest because of its large penetration depth and maximum permissible exposure. Now, the supramolecular radical ...dimer, fabricated by N,N′‐dimethylated dipyridinium thiazolo5,4‐dthiazole radical cation (MPT.+) and cucurbit8uril (CB8), achieves strong absorption at NIR‐II biowindow. The supramolecular radical dimer (2MPT.+‐CB8) showed highly efficient photothermal conversion and improved stability, thus contributing to the strong inhibition on HegG2 cancer cell under 1064 nm irradiation even penetrating through chicken breast tissue. This work provides a novel approach to construct NIR‐II chromophore by tailor‐made assembly of organic radicals. It is anticipated that this study provides a new strategy to achieve NIR‐II photothermal therapy and holds promises in luminescence materials, optoelectronic materials, and also biosensing.
Host‐enhanced intermolecular charge transfer enabled the fabrication of a supramolecular radical dimer with strong absorption in the NIR‐II biowindow and high stability. The dimer exhibited high‐efficiency photothermal conversion and strong inhibition on cancer cells through NIR‐II photothermal therapy.
Designing nanocomposite hydrogels with oriented nanosheets has emerged as a promising toolkit to achieve preferential performances that go beyond their disordered counterparts. Although current ...fabrication strategies via electric/magnetic force fields have made remarkable achievements, they necessitate special properties of nanosheets and suffer from an inferior orientation degree of nanosheets. Herein, a facile and universal approach is discovered to elaborate MXene‐based nanocomposite hydrogels with highly oriented, heterogeneous architecture by virtue of supergravity to replace conventional force fields. The key to such architecture is to leverage bidirectional, force‐tunable attributes of supergravity containing coupled orthogonal shear and centrifugal force field for steering high‐efficient movement, pre‐orientation, and stacking of MXene nanosheets in the bottom. Such a synergetic effect allows for yielding heterogeneous nanocomposite hydrogels with a high‐orientation MXene‐rich layer (orientation degree, f = 0.83) and a polymer‐rich layer. The authors demonstrate that MXene‐based nanocomposite hydrogels leverage their high‐orientation, heterogeneous architecture to deliver an extraordinary electromagnetic interference shielding effectiveness of 55.2 dB at 12.4 GHz yet using a super‐low MXene of 0.3 wt%, surpassing most hydrogels‐based electromagnetic shielding materials. This versatile supergravity‐steered strategy can be further extended to arbitrary nanosheets including MoS2, GO, and C3N4, offering a paradigm in the development of oriented nanocomposites.
A novel supergravity‐steered approach is designed to manipulate the assembly of arbitrary nanosheets from MXene to MoS2, GO, and C3N4 for fabricating oriented nanocomposite hydrogels with heterogeneous architecture. The resultant MXene‐based nanocomposite hydrogels showcase an extraordinary electromagnetic interference shielding effectiveness (EMI SE) of 55.2 dB yet using a super‐low MXene of 0.3 wt%, surpassing most hydrogels‐based electromagnetic shielding materials.
GeSe has recently emerged as a promising photovoltaic absorber material due to its attractive optical and electrical properties as well as earth-abundant and low-toxic constituent elements. However, ...no photovoltaic device has been reported based on this material so far, which could be attributed to the inevitable coexistence of phase impurities Ge and GeSe2, leading to detrimental recombination-center defects and seriously degrading the device performance. Here we overcome this issue by introducing a simple and fast (4.8 μm min–1) rapid thermal sublimation (RTS) process designed according to the sublimation feature of the layered structured GeSe. This new method offers a compelling combination of assisting raw material purification to suppress deleterious phase impurities and preventing the formation of detrimental point defects through congruent sublimation of GeSe, thus providing an in situ self-regulated process to fabricate high quality polycrystalline GeSe films. Solar cells fabricated following this process show a power conversion efficiency of 1.48% with good stability. This preliminary efficiency and high stability, combined with the self-regulated RTS process (also extended to the fabrication of other binary IV-VI chalcogenide films, i.e., GeS), demonstrates the great potential of GeSe for thin-film photovoltaic applications.
Pollution of residual plastic film in arable lands is a severe problem in China. In this study, the status of residual film and influential factors were investigated using the methods of farm survey ...in combination with questionnaires and quadrat sampling at a large number of field sites in Xinjiang Uygur Autonomous Region, China. The results showed that the amount of film utilization increased largely and reached to 1.8×10~5 t in 2013. Similarly, the mulching area also substantially increased in recent decades, and reached to 2.7×10~5 ha in the same year. According to the current survey, 60.7% of the sites presented a greater mulch residue than the national film residue standard（75 kg ha~（–1））, and the maximum residual amount reached 502.2 kg ha~（–1） in Turpan, Xinjiang. The film thickness, the mulching time and the crop type all influenced mulch residue. The thickness of the film had significantly negative correlation with the amount of residual film（P0.05）, while the mulching years had significantly positive correlation with it（P0.05）. The total amount of residual film in Xinjiang was 3.43×105 t in 2011, which accounted for 15.3% of the cumulative dosage of mulching. Among all the crops, the cotton fields had the largest residual amount of mulch film（158.4 kg ha~（–1））, and also the largest contribution（2.6×10~5 tons） to the total amount of residual film in Xinjiang.
The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), infected over 3300 healthcare workers in early 2020 in China. Little information is known about nosocomial ...infections of healthcare workers in the initial period. We analysed data from healthcare workers with nosocomial infections in Wuhan Union Hospital (Wuhan, China) and their family members.
We collected and analysed data on exposure history, illness timelines and epidemiological characteristics from 25 healthcare workers with laboratory-confirmed coronavirus disease 2019 (COVID-19) and two healthcare workers in whom COVID-19 was highly suspected, as well as 10 of their family members with COVID-19, between 5 January and 12 February 2020. The demographics and clinical features of the 35 laboratory-confirmed cases were investigated and viral RNA of 12 cases was sequenced and analysed.
Nine clusters were found among the patients. All patients showed mild to moderate clinical manifestation and recovered without deterioration. The mean period of incubation was 4.5 days, the mean±sd clinical onset serial interval (COSI) was 5.2±3.2 days, and the median virus shedding time was 18.5 days. Complete genomic sequences of 12 different coronavirus strains demonstrated that the viral structure, with small irrelevant mutations, was stable in the transmission chains and showed remarkable traits of infectious traceability.
SARS-CoV-2 can be rapidly transmitted from person to person, regardless of whether they have symptoms, in both hospital settings and social activities, based on the short period of incubation and COSI. The public health service should take practical measures to curb the spread, including isolation of cases, tracing close contacts, and containment of severe epidemic areas. Besides this, healthcare workers should be alert during the epidemic and self-quarantine if self-suspected of infection.
As lithium‐ion batteries continue to climb to even higher energy density, they meanwhile cause serious concerns on their stability and reliability during operation. To make sure the electrode ...materials, particularly cathode materials, are stable upon extended cycles, surface modification becomes indispensable to minimize the undesirable side reaction at the electrolyte–cathode interface, which is known as a critical factor to jeopardizing the electrode performance. This Review is targeted at a precise surface control of cathode materials with focus on the synthetic strategies suitable for a maximized surface protection ensured by a uniform and conformal surface coating. Detailed discussions are taken on the formation mechanism of the designated surface species achieved by either wet‐chemistry routes or instrumental ones, with attention to the optimized electrochemical performance as a result of the surface control, accordingly drawing a clear image to describe the synthesis–structure–performance relationship to facilitate further understanding of functional electrode materials. Finally, perspectives regarding the most promising and/or most urgent developments for the surface control of high‐energy cathode materials are provided.
Surface modification of cathode materials is indispensable to stabilize the cathode–electrolyte interface. The synthesis strategies suited for the creation of a uniform shell with thickness controlled at nanometer accuracy are introduced, with the corresponding formation mechanisms discussed in detail, in order to present the synthesis–structure–performance relationship to facilitate understanding of the stability of high‐energy electrode materials.
Dispersal limitation and environmental filtering were recognized as the main dispersal‐based and niche‐based processes responsible for community assembly. These interactions usually leave more ...spatial signatures in sapling communities and create detectable spatial patterns in different functional types of species. We investigated saplings of pioneer and non‐pioneer species, which facilitated an understanding of species co‐existence and biodiversity recovery. Based upon mapped tree data in the subtropical evergreen broad‐leaved forest dynamics plot in Taiwan, we endeavored to: (1) determine the different spatial scales contributing to distribution patterns of pioneer and non‐pioneer saplings; (2) understand how dispersal limitation affects distribution of pioneer and non‐pioneer saplings; and (3) evaluate the degree to which the different environmental factors explain variation in species composition in pioneer and non‐pioneer saplings. We used the principal coordinates of neighbor matrices (PCNM) method, and variation partitioning to disentangle the contributions of these processes. Fine‐scale spatial patterns were more important for pioneer than for non‐pioneer saplings. Dispersal limitation was the main process influencing the spatial distribution of the non‐pioneer saplings. Environmental filtering was also an important process regulating the spatial distribution of saplings for both functional types, especially for pioneer saplings. Disturbance effects contributed to fine‐scale spatial variation in pioneer saplings, whereas topographic and soil effects contributed to broad and medium scale spatial variation in non‐pioneer saplings. It was evident that different spatial patterns of saplings of different functional types served to facilitate tree regeneration and maintain species co‐existence in this subtropical broad‐leaved forest.
Dispersal limitation was the main process influencing the spatial distribution of the non‐pioneer saplings. Environmental filtering was also an important process regulating the spatial distribution of saplings for both functional types, especially for pioneer saplings.
The complexity of chemical compounds in lithium‐ion batteries (LIBs) results in great difficulties in the extraction of multiple transition metals, which have similar physicochemical characteristics. ...Here, we propose a novel strategy for selective extraction of nickel, cobalt, and manganese from spent LiNixCoyMn1−x−yO2 (NCM) cathode through the regulation of coordination environment. Depending on adjusting the composition of ligand in transition metal complexes, a tandem leaching and separation system is designed and finally enables nickel, cobalt, and manganese to enrich in the form of NiO, Co3O4, and Mn3O4 with high recovery yields of 99.1 %, 95.1 %, and 95.3 %, respectively. We further confirm that the combination of different transition metals with well‐designed ligands is the key to good selectivity. Through our work, fine‐tuning the coordination environment of metal ions is proved to have great prospects in the battery recycling industry.
The deep eutectic solvent composed of choline chloride and oxalic acid was prepared. After leaching at 120 °C for 10 hours, the nickel oxalate dihydrate and the filtrate containing other metal elements are separated. Then the filtrate is diluted with water to precipitate the cobalt oxalate dihydrate. Finally, manganese compounds were separated by adjusting pH.
Owing to the similarities in raw materials, technology, and application fields between fiberboard and particleboard, it is crucial to perform a comparative life cycle assessment (LCA) on these two ...types of panels. This comparison can greatly contribute to a comprehensive understanding of the environmental impact of these panels. However, there is a limited number of studies available regarding the comparative LCA study of these panels. Therefore, in this study, the environmental effects of manufacturing process of dry-process fiberboard (medium-density fiberboard, MDF) and particleboard (PB) were compared. A cradle-to-gate LCA model was developed using eFootprint software. The results showed that PB exhibited better environmental performance than MDF because of the lower power consumption and the amount of urea-formaldehyde (UF) resin required in the manufacturing process. The total environmental impact of PB from cradle to gate was 27.5% lower than that of MDF, and the eco-efficiency of PB was 18.8% higher than that of MDF. Regardless of the panel type, the greatest environmental effect occurred in the raw and auxiliary materials production phase, followed by the board production phase. The environmental effect of the transportation phase was minimal. The production of UF resin and the consumption of electricity were identified as the main environmental hotspots. Finally, two approaches to enhance environmental performance were proposed and applied: first, replacing UF resin with a soy-based adhesive, and second, switching from thermal power to hydropower. In addition, the environmental impacts before and after implementing these approaches were compared.
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•Particleboard has better environmental performance than medium density fiberboard.•Urea-formaldehyde resin and electricity are the key environmental hotspots.•Soy-based adhesive doesn't outperform urea-formaldehyde resin in all impacts.
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