To improve the rendering effect of artistic images, a method enhancing features of artistic images is proposed based on histogram equalization and bilateral filtering in the article. Firstly, ...artistic images are divided into both high and low-frequency representations, and the multi-step enhancement processing level is delimited by multi-band decomposition. Secondly, the noise in the image is removed by bilateral filtering. Then, the grey-level histogram of the image is modified by using the histogram equalization. Finally, the features of the artistic image are enhanced by global tone mapping after histogram equalization processing is conducted. Then, the image is sharpened to improve the enhancement effect further. The experiments show that the features of the color and edge details turn out to be more vivid and clearer after the proposed method is implemented. The structural similarity (SSIM) measure of the image increases to 0.973, and the average gradient gets close to 0.8, which shows that the proposed method is effective.
Context: China’s reforms of long-term care stem from significant demographic and socio-economic changes since the 1980s. The growing involvement of the market in care provision for older people is a ...notable trend in its urban areas. Objective: This study investigates how the marketisation process is shaping home care policy and practice in urban China. Methods: Qualitative case study research was conducted in Shanghai. The data source includes interviews with 21 care provider representatives and 9 local government officials and follow-up consultations with 4 interviewees. Interview data were analysed thematically. Findings: This article outlines three quasi-market models and power dynamics in Shanghai’s home care sector, reflecting marketisation strategies and state-market relationships: the state-controlled model, the limited competition model, and the free market model. In Shanghai’s home care market, heightened competition does not necessarily correlate with improved care quality, echoing international concerns such as disparities in access, care quality, and market concentration. These challenges extend beyond ‘market failures’ and increased risks to older people but also contradict the rhetoric of markets as being more responsive to consumers. Limitations: The study only included Shanghai as the research site. It is an exploratory study that requires additional statistical data for future research. Implications: This study underscores the influence of long-term care policy and local government characteristics on purchaser–provider relationships in commissioning and public procurement. The findings suggest that robust regulation and monitoring within the care market is crucial for mitigating associated risks and prioritising care quality during the development of the care market.
We study the exact chirped solutions of the perturbed Chen-Lee-Liu equation with a refractive index. Exact chirped solutions and their corresponding chirps are obtained using trial equation method ...and complete discrimination system for polynomial. Illustrations are presented under certain parameter conditions. Chen-Lee-Liu model describes pulse propagation in optical fibers. Studying chirped solutions to the perturbed Chen-Lee-Liu equation with a refractive index could improve the understanding of physical phenomena and may have applications in the design of optical fibers.
Herein, recent developments of metal–organic frameworks (MOFs) structured into nanofibers by electrospinning are summarized, including the fabrication, post‐treatment via pyrolysis, properties, and ...use of the resulting MOF nanofiber architectures. The fabrication and post‐treatment of the MOF nanofiber architectures are described systematically by two routes: i) the direct electrospinning of MOF‐polymer nanofiber composites, and ii) the surface decoration of nanofiber structures with MOFs. The unique properties and performance of the different types of MOF nanofibers and their derivatives are explained in respect to their use in energy and environmental applications, including air filtration, water treatment, gas storage and separation, electrochemical energy conversion and storage, and heterogeneous catalysis. Finally, challenges with the fabrication of MOF nanofibers, limitations for their use, and trends for future developments are presented.
Metal–organic framework based nanofibers with hierarchical porous structure fabricated via electrospinning are reviewed for energy and environmental applications.
Based on 1553 media reports on food safety scandals and concerns, we conducted an aggregated analysis on economically motivated food frauds and adulterations in China. A systematic approach is used ...to analyze the country's food safety concern in terms of fraud type, implicated foods, adulterants, contaminants and abnormal conditions, and concerned food sources. This study indicate that economically motivated food fraud and adulteration was an emerging and serious food safety problem in China. The results of the study can be used not only to analyze food safety risks but also to prioritize target areas for food policy-making and enforcement of food safety regulation.
•A systematic review was conducted based on 1553 media reports regarding China's food safety problem.•The result of the paper indicates that economically motivated food fraud and adulteration was emerging in China.•Many adulterants, contaminants and abnormal conditions have been identified in foods.
Design of economical, large-scale, stable, and highly active bifunctional electrocatalysts for Zn-air batteries with enhanced oxygen reduction and oxygen evolution performance is needed. Herein, a ...series of electrocatalysts were facilely fabricated where
in situ
formed bimetallic nanoparticles aided in the growth of carbon nanotubes over carbon nanofibers (MM'-CNT@CNF) during thermal treatment. Different combinations of Fe, Ni, Co and Mn metals and melamine as precursor for CNT growth were investigated. The synergistic interaction between bimetallic nanoparticles and N-doped carbon results in greatly improved bifunctional catalytic activity for both oxygen reduction and evolution reactions (ORR, OER) using FeNi-CNT@CNF as catalyst. The half-wave potential (0.80 V
vs.
RHE) for FeNi-CNT@CNF for ORR was close to that of Pt/C (0.79 V
vs.
RHE), meanwhile its stability was superior to Pt/C. Likewise, during OER, the FeNi-CNT@CNF reached a current density of 10 mA cm
−2
at a rather low overpotential of 310 mV
vs.
RHE compared to benchmark RuO
2
(410 mV). The rechargeable Zn-air prototype battery using FeNi-CNT@CNF as an air electrode outperformed the mixture of Pt/C and RuO
2
with discharge/charge overpotential of 0.61 V, power density of 118 mW cm
−2
at 10 mA cm
−2
and an improved cycling stability over 108 hours.
In situ
formed bimetallic nanoparticles aided the growth of CNTs over CNFs for enhanced oxygen reduction and evolution reactions in ZABs.
Unraveling the relative importance of ecological processes regulating microbial community structure is a central goal in microbial ecology. Here, we used high-throughput sequencing to examine the ...relative contribution of selective and neutral processes in the assembly of abundant and rare subcommunities from three subtropical bays of China. We found that abundant and rare bacterial taxa were distinctly different in diversity, despite the similar biogeographic patterns and strong distance-decay relationships, but the dispersal of rare bacterial taxa was more limited than that of abundant taxa. Furthermore, the environmental (selective processes) and spatial (neutral processes) factors seemed to govern the assembly and biogeography of abundant and rare bacterial subcommunities, although both factors explained only a small fraction of variation within the rare subcommunity. More importantly, variation partitioning (based on adjusted R
in redundancy analysis) showed that spatial factors exhibited a slightly greater influence on both abundant and rare subcommunities compared to environmental selection; however, the abundant subcommunity had a much stronger response to spatial factors (17.3% of pure variance was explained) than that shown by the rare bacteria (3.5%). These results demonstrate that environmental selection and neutral processes explained the similar biogeographic patterns of abundant and rare subcommunities, but a large proportion of unexplained variation in the rare taxa (91.1%) implies that more complex assembly mechanisms may exist to shape the rare bacterial assemblages in the three subtropical bays.
High-quality InP-based quantum dots (QDs) have become very promising, environmentally benign light emitters for display applications, but their synthesis generally entails hazardous hydrofluoric ...acid. Here, we present a highly facile route to InP/ZnSe/ZnS core/shell/shell QDs with a near-unity photoluminescence quantum yield. As the key additive, the inorganic salt ZnF2 mildly reacts with carboxylic acid at a high temperature and in situ generates HF, which eliminates surface oxide impurities, thus facilitating epitaxial shell growth. The resulting InP/ZnSe/ZnS QDs exhibit a narrower emission line width and better thermal stability in comparison with QDs synthesized with hydrofluoric acid. Light-emitting diodes using large-sized InP/ZnSe/ZnS QDs without replacing original ligands achieve the highest peak external quantum efficiency of 22.2%, to the best of our knowledge, along with a maximum brightness of >110 000 cd/m2 and a T 95 lifetime of >32 000 h at 100 cd/m2. This safe approach is anticipated to be applied for a wide range of III–V QDs.
The developments of theoretical studies on NHC‐catalyzed n+2 (n=2, 3, 4) and other cycloaddition/annulation reactions have been summarized in this review. The detailed mechanisms, role of NHC, and ...origin of chemo‐ and stereoselectivity of these kinds of reactions were illustrated to provide valuable insights for rational design of new NHC‐catalyzed cycloaddition/annulation reactions with high selectivities. Moreover, computational and theoretical methods commonly used were also mentioned to open the door for deep exploration of the general principle for NHC‐catalyzed reactions within theoretical chemistry.
Carbene catalyzed: The developments of theoretical studies on NHC‐catalyzed n+2 (n=2, 3, 4) and other cycloaddition/annulation reactions have been summarized in this review. The detailed mechanisms, role of NHC, and origin of chemo‐ and stereoselectivity of these kinds of reactions were illustrated.
Multi-heteroatoms-doping tunes the electronic structure of the catalyst, thereby optimizing the intrinsic catalytic activity of tri-functional metal-free electrocatalyst.
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•This work ...provides a self-sacrifice template engineering strategy to synthesize NSCHCT as tri-functional metal-free electrocatalyst.•NSCHCT shows an excellent bifunctional performance towards ORR/OER and has a small ORR/OER voltage difference of 0.85 V.•The hollow hierarchical porous structure and multi-heteroatom-doped provide rich reactive sites.•ZAB based on NSCHCT1000 displays long-term stability of 55 h, which can drive a LED.
Developing non-noble metal-based electrocatalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) is highly desirable, while still facing challenges. Herein, a self-sacrifice template engineering strategy that feasible carbonization of the copolymer of melamine-trithiocyanurim wrapped by polydopamine was developed to fabricate N, S hollow co-doped carbon tube (NSCHCT) based trifunctional electrocatalyst. Owing to the hierarchical structure, including hollow and porous structure, the obtained catalyst exhibits rich active sites and favourable mass transfer advantage, boosting the kinetic of the catalytic process. Moreover, multiple heteroatoms-doping provides various active sites. Notably, the thiophene sulfur combining with pyridinic N(p-N/S) and thiophene sulfur combined with graphitic N (g-N/S) shows the lowest activation energy barrier for OER/ORR and HER, respectively. As a result, the NSCHCT assembled Zinc-air battery shows excellent performance with a power density of 109 mW cm−2 and a high open-circuit voltage of 1.44 V, comparable with the Pt/C + RuO2 system.
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