Effective capture of radioactive iodine is of paramount importance for the safe and long‐term storage of fission products in the nuclear fuel cycle. Herein, a series of functionalized Th‐UiO‐66 MOFs ...was employed as a model to investigate the effects of substituents on iodine adsorption in both solution and vapor states. Sorption studies revealed that the electro‐donating amino group exhibits the most positive role on increasing the removal rate of iodine from cyclohexane and the uptake capacity of iodine vapor. Particularly, the disubstituted Th‐UiO‐66‐(NH2)2 can effectively remove 91.9 % of iodine (300 mg L−1) from cyclohexane and capture 969 mg g−1 iodine vapor, significantly higher than 59.6 % and 334 mg g−1 of untagged Th‐UiO‐66, respectively. In addition, the substituent effect on the radiolytic stability of MOFs was for the first time investigated, leading to the unearthing of one of the most radioresistant MOFs Th‐UiO‐66‐NH2 reported to date.
A systematic study on the effects of aromatic substitution on iodine adsorption was performed by employing Th‐UiO‐66 as a platform, giving rise to the disubstituted Th‐UiO‐66‐(NH2)2 with the best iodine sorption performance. Moreover, aromatic substitution was employed as a new strategy to enhance the radioresistance of MOFs.
Background and Aims
Hepatic ischemia–reperfusion injury (IRI) is a common complication of hepatectomy and liver transplantation. However, the mechanisms underlying hepatic IRI have not been fully ...elucidated. Regulator of G‐protein signaling 14 (RGS14) is a multifunctional scaffolding protein that integrates the G‐protein and mitogen‐activated protein kinase (MAPK) signaling pathways. However, the role of RGS14 in hepatic IRI remains unclear.
Approach and Results
We found that RGS14 expression increased in mice subjected to hepatic ischemia–reperfusion (IR) surgery and during hypoxia reoxygenation in hepatocytes. We constructed global RGS14 knockout (RGS14‐KO) and hepatocyte‐specific RGS14 transgenic (RGS14‐TG) mice to establish 70% hepatic IRI models. Histological hematoxylin and eosin staining, levels of alanine aminotransferase and aspartate aminotransferase, expression of inflammatory factors, and apoptosis were used to assess liver damage and function in these models. We found that RGS14 deficiency significantly aggravated IR‐induced liver injury and activated hepatic inflammatory responses and apoptosis in vivo and in vitro. Conversely, RGS14 overexpression exerted the opposite effect of the RGS14‐deficient models. Phosphorylation of TGF‐β‐activated kinase 1 (TAK1) and its downstream effectors c‐Jun N‐terminal kinase (JNK) and p38 increased in the liver tissues of RGS14‐KO mice but was repressed in those of RGS14‐TG mice. Furthermore, inhibition of TAK1 phosphorylation rescued the effect of RGS14 deficiency on JNK and p38 activation, thus blocking the inflammatory responses and apoptosis.
Conclusions
RGS14 plays a protective role in hepatic IR by inhibiting activation of the TAK1–JNK/p38 signaling pathway. This may be a potential therapeutic strategy for reducing incidences of hepatic IRI in the future.
A novel and efficient Fe-catalyzed radical cycloaddition of 2H-azirines and enamides for the synthesis of substituted pyrroles has been developed. The radical cycloaddition reaction proceeded through ...a conceptually new Fe(II)-catalyzed homolytic cleavage of C–N bond of 2H-azirines sequential radical cyclization with enamides. The reaction used readily available starting materials, tolerated various functional groups, and afforded valuable triaryl-substituted pyrroles in good to high yields under mild reaction conditions.
•In recent years, China has prioritized ecological security (ES)•An improved ecological footprint model can effectively assess ecological security.•Poor ES is found in eastern coastal areas and the ...second-third step boundary.•China should consider ES, energy security, and food security in future development.
With the outbreak of the current global eco-environmental crisis, ensuring global and local ecological security (ES) has become a priority for many countries in the world. In the past few decades, social and economic development in China has induced many ecological and environmental problems, which have negatively impacted ES of China and the world. In recent years, with the increasing awareness of China’s ecological and environmental protection, the Chinese government has actively participated in global ecological and environmental governance and raised ES to the height of national security. A systematic and comprehensive assessment of ES is the basis of ES assurance, which can enable governments to accurately grasp the ES status of different regions and adopt targeted management measures. The ecological footprint (EF) model is a mature model that has been widely used for ES assessment. Thus, this study used an EF model with localized parameters analyzing the spatiotemporal changes in China’s ES from 2006 to 2016 on a provincial scale. Then, from an “occupation-carrying” perspective, this study explored the main aspect that induced changes in regional ES and identified the main type of ecological land that threatened regional ES. Results showed that a) during the study period, China’s ES status showed a deteriorating trend and the current ES is not optimistic. However, the ecological carrying capacity of most provinces in China has increased, indicating that China’s ecological and environmental protection has achieved initial results; b) currently, the provinces whose ES status are moderate unsafe and quite unsafe are mainly distributed in the eastern coastal region and the region near the boundary between the second and third ladders; c) the high-intensity occupation of the ecological environment and biological resources attributed to the rapid development of the social economy is the main cause for the negative changes in ES in most areas; d) for most provinces in China, cropland occupation and fossil energy consumption pose great threats to the regional ES status. China should jointly consider ES, energy security, and food security in its future development plans.
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•The property, category, synthesis, characterization and application of LDH-based catalysts are summarized.•Activation and mechanism of LDH-based catalysts in three kinds of AOPs are ...discussed.•LDH-based catalysts show superior catalytic performance for various refractory organics removal.•The prospects and challenges of LDH-based catalysts are proposed.
Layered double hydroxides (LDHs) are a class of anionic clays with flexible tunability, facile exchangeability of intercalated anions, good thermal stability, and plentiful active sites. By virtue of their advantages, LDHs, as catalysts, catalyst precursors or catalyst supports, have been widely used in advanced oxidation processes (AOPs) to degrade organic pollutants in water and showed prominent catalytic performance as concluded from nearly 100% removal of contaminants in a relatively short time. To shed light on the synthesis, application and catalytic performance of LDH-based catalysts, this review summarized the properties, categories, synthesis and characterization methods of LDH-based catalysts, and their applications, reaction mechanisms and the corresponding influencing factors in heterogeneous Fenton-like processes, sulfate radical based AOPs and photocatalysis. Compared with LDHs, LDOs and nanocomposites possess other performances that are beneficial for AOPs catalytic processes, such as good dispersity, easy separability and synergistic effect. Moreover, the optimum material design and corresponding reaction mechanisms would be varied with the types of AOPs. In the end, based on the current challenges in LDH-based catalysts, future researches are suggested to focus on developing green and efficient synthetic method, optimizing material design, and promoting their practical application.
Due to the increasing complexity of optimization problems, distributed differential evolution (DDE) has become a promising approach for global optimization. However, similar to the centralized ...algorithms, DDE also faces the difficulty of strategies' selection and parameters' setting. To deal with such problems effectively, this article proposes an adaptive DDE (ADDE) to relieve the sensitivity of strategies and parameters. In ADDE, three populations called exploration population, exploitation population, and balance population are co-evolved concurrently by using the master-slave multipopulation distributed framework. Different populations will adaptively choose their suitable mutation strategies based on the evolutionary state estimation to make full use of the feedback information from both individuals and the whole corresponding population. Besides, the historical successful experience and best solution improvement are collected and used to adaptively update the individual parameters (amplification factor <inline-formula> <tex-math notation="LaTeX">{F} </tex-math></inline-formula> and crossover rate CR) and population parameter (population size <inline-formula> <tex-math notation="LaTeX">{N} </tex-math></inline-formula>), respectively. The performance of ADDE is evaluated on all 30 widely used benchmark functions from the CEC 2014 test suite and all 22 widely used real-world application problems from the CEC 2011 test suite. The experimental results show that ADDE has great superiority compared with the other state-of-the-art DDE and adaptive differential evolution variants.
The rheological properties of raw materials as 3D printing inks play a vital role in their printability and quality. This work was aimed to evaluate the potential of low field nuclear magnetic ...resonance (LF-NMR) and dielectric characteristics (at 915 and 2450 MHz) to predict the rheological properties and estimate the printability of surimi gels at different NaCl and water concentrations. Hierarchical cluster analysis of rheological parameters showed four groups of surimi gels, which were described as difficult extrusion, good extrusion and self-supporting, good extrusion but poor self-supporting, and difficult formation. Comparison of two monitoring techniques, discriminant analysis based on LF-NMR showed a higher classification accuracy of printability in samples, and partial least squares regression (PLSR) models using LF-NMR for predicting main rheological properties had better predictive accuracy and robustness. Thus, the study indicated that LF-NMR has a great potential in predicting rheological properties and estimating the printability of surimi gels.
•Hierarchical cluster analysis of rheological parameters showed four groups of samples.•LF-NMR and dielectric parameters were partially relevant with rheological properties.•Better prediction obtained of multiple rheological parameters simultaneously by LF-NMR.•LF-NMR has a great potential for printability assessment of surimi gels.
The effects of feeding sequence of reactants on the properties of a MgAl layered double hydroxide (LDH) coating on Mg alloy are reported herein for the first time. Based on the X-ray diffraction ...(XRD) patterns and Fourier transform infrared (FTIR) spectra, MgAl-LDH coatings were successfully obtained with different feeding sequences. However, characterizations of scanning electron microscopy (SEM) and electrochemical methods show that the surface morphologies and corrosion resistance of the MgAl-LDH coatings are dependent upon the feeding sequence. Furthermore, the MgAl-LDH coatings were modified in an 8-quinolinol (8HQ) solution by a facile soaking measurement. Energy dispersive X-ray spectroscopy (EDS) maps and X-ray photoelectron spectroscopy (XPS) spectra demonstrate the effective adsorption of 8HQ layer on the MgAl-LDH primer. The high-resolution N 1s XPS spectra manifest the existence of chemisorption owing to formation of a complex chelate, (bis (8-hydroxyquinolinato) magnesium, Mg(HQ)2), between 8HQ anions and dissolved Mg2+. The modified MgAl-LDH coatings, which are named as 8HQ@MgAl-LDH coatings in the body text, show significant enhancement in corrosion resistance and remains excellent corrosion protection even exposure to a NaCl aqueous solution for one month. The mechanism of corrosion inhibition for the 8HQ@MgAl-LDH coatings is proposed finally, which mainly includes the increase in water contact angles, Cl− and CO32− anion-exchangeability, and redeposition of Mg(HQ)2 precipitation. These findings of this study provide some valuable insights into the corrosion protection mechanism of the MgAl-LDH coatings and the designment of a highly corrosion resistant coating on Mg alloy and other lightweight alloys.
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•MgAl layered double hydroxide (MgAl-LDH) coatings grew in situ on AZ31 Mg alloy.•Properties of the MgAl-LDH coatings are feeding sequence dependence.•Corrosion inhibition of MgAl-LDH coating is enhanced after 8-quinolinol treatment.•Chemisorption of 8-quinolinol on the MgAl-LDH coating surface was identified.•A mechanism of corrosion protection for the MgAl-LDH coatings has been proposed.
Expensive optimization problem (EOP) widely exists in various significant real-world applications. However, EOP requires expensive or even unaffordable costs for evaluating candidate solutions, which ...is expensive for the algorithm to find a satisfactory solution. Moreover, due to the fast-growing application demands in the economy and society, such as the emergence of the smart cities, the internet of things, and the big data era, solving EOP more efficiently has become increasingly essential in various fields, which poses great challenges on the problem-solving ability of optimization approach for EOP. Among various optimization approaches, evolutionary computation (EC) is a promising global optimization tool widely used for solving EOP efficiently in the past decades. Given the fruitful advancements of EC for EOP, it is essential to review these advancements in order to synthesize and give previous research experiences and references to aid the development of relevant research fields and real-world applications. Motivated by this, this paper aims to provide a comprehensive survey to show why and how EC can solve EOP efficiently. For this aim, this paper firstly analyzes the total optimization cost of EC in solving EOP. Then, based on the analysis, three promising research directions are pointed out for solving EOP, which are problem approximation and substitution, algorithm design and enhancement, and parallel and distributed computation. Note that, to the best of our knowledge, this paper is the first that outlines the possible directions for efficiently solving EOP by analyzing the total expensive cost. Based on this, existing works are reviewed comprehensively via a taxonomy with four parts, including the above three research directions and the real-world application part. Moreover, some future research directions are also discussed in this paper. It is believed that such a survey can attract attention, encourage discussions, and stimulate new EC research ideas for solving EOP and related real-world applications more efficiently.
There are two phenomena in human society and biological systems. One is that people prefer to extract knowledge from multiple exemplars to obtain better learning ability. The other one is the ...forgetting ability that helps the encoding and consolidation of new information by removing unused or unwanted memories. Inspired by these phenomena, this paper transplants the multi-exemplar and forgetting ability to particle swarm optimization (PSO), and proposes an eXpanded PSO, called XPSO. Firstly, XPSO expands the “social-learning” part of each particle from one exemplar to two exemplars, learning from both the locally and the globally best exemplars. Secondly, XPSO assigns different forgetting abilities to different particles, simulating the forgetting phenomenon in the human society. Under the multi-exemplar learning model with forgetting ability, XPSO further adopts an adaptive scheme to update the acceleration coefficients and selects a reselection mechanism to update the population topology. The effectiveness of these additional proposed strategies is verified by extensive experiments. Moreover, comparison results among XPSO and other 9 popular PSO as well as 3 non-PSO algorithms on CEC’13 test suite suggest that XPSO attains a very promising performance for solving different types of functions, contributing to both higher solution accuracy and faster convergence speed.
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