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With the development of energy technology, hydrogen is gradually becoming widely used. China is also rapidly developing its own hydrogen energy industry in an effort to accomplish the "dual carbon target'. Hydrogen from methane is one of the mainstream sources, of which hydrogen from methane cracking is the decomposition of methane into hydrogen and solid carbon, with the solid carbon also having a high economic value. In particular, this technology does not emit carbon dioxide, which is very friendly to the environment, but it cannot avoid larger energy consumption. In contrast, hydrogen production from methane cracking driven by solar energy not only combines the characteristics of no CO 2 emission, but also greatly reduces the consumption of primary energy, which is the future development trend of hydrogen production from methane. This paper provides a brief overview of the various technological pathways for methane to hydrogen production in the context of China's actual development, focusing on the current status of the development and application of solar methane cracking to hydrogen production technologies at home and abroad. Among them, this paper mainly discusses the characteristics of solar reactors of different sizes and structures, and summarizes the results of related optimization studies. Meanwhile, the application of catalysts in solar reactors and the problem of carbon deposition are analyzed, and the practical application of solar methane cracking hydrogen production system is outlined. Finally, the future development of solar methane cracking hydrogen production technology is prospected from the national situation of China. [Display omitted] • Solar methane cracking for hydrogen can reduce emissions and energy consumption. • The current state of research on solar reactors is summarized. • Solar methane cracking requires higher performing catalysts. • Providing insights into the future development of solar methane cracking in China. [ABSTRACT FROM AUTHOR]

Ligustrum lucidum W.T. Aiton is an outstanding herb with the homology of medicine and food. Its ripe fruits are traditionally used as an important tonic for kidneys and liver in China. Ligustrum lucidum W.T. Aiton is rich in nutritional components and a variety of bioactive ingredients. A total of 206 compounds have been isolated and identified, they mainly include flavonoids, phenylpropanoids, iridoid glycosides, and triterpenoids. These compounds exert anti-osteoporosis, anti-tumor, liver protective, antioxidant, antiinflammatory, and immunomodulatory effects. Ligustrum lucidum W.T. Aiton has been traditionally used to treat many complex diseases, including osteoporotic bone pain, rheumatic bone, cancer, related aging symptoms, and so on. In the 2020 Edition of Chinese Pharmacopoeia, there are more than 100 prescriptions containing L. lucidum W.T. Aiton. Among them, some classical preparations including Er Zhi Wan and Zhenqi fuzheng formula, are used in the treatment of various cancers with good therapeutic effects. Additionally, L. lucidum W.T. Aiton has also many excellent applications for functional food, ornamental plants, bioindicator of air pollution, algicidal agents, and feed additives. Ligustrum lucidum W.T. Aiton has rich plant resources. However, the application potential of it has not been fully exploited. We hope that this paper provides a theoretical basis for the high-value and high-connotation development of L. lucidum W.T. Aiton in the future. [ABSTRACT FROM AUTHOR]

China faces a critical economic structural transformation with increasing financial instability and uncertainty, necessitating a greater need for accurate measurement of systemic financial risk. In the paper, this work analyses the systemic financial risk in China between 2011 and 2020 based on financial development, fragility and risk indicators and the world economy to construct a comprehensive index of systemic financial risk (CISFR). The results show an upward trend in China's financial risk in the past 10 years and a mid-to-high level fluctuation in the past five years, mainly driven by risks in the banking system, securities market and real estate market. In 2021–2022, China's financial system is still in a high-risk stage, and high systemic risks are still an important economic issue. The study's comprehensive index method can be extended to emerging economies. It reflects the main driving factors of financial risk by assigning weights to basic indicators from a multidimensional perspective, thus providing a reference for policymakers to prevent and control financial risk. [ABSTRACT FROM AUTHOR]

Applying artificial intelligence in education is relevant to addressing the current educational crises. Many available solutions apply Convolutional Neural Networks (CNNs) to help improve educational outcomes. Therefore, a series of works have been developed integrating techniques in different educational contexts, for instance, in online teaching practices. Given the various studies and the relevance of CNNs for educational applications, this paper presents a systematic literature review to discuss the state-of-the-art. We reviewed 133 papers from the IEEE Xplore, ACM Digital Library, and Scopus databases. Based on our revision, we discuss characteristics of studies such as publication venues, educational context, datasets, types of CNNs models, and performance of models. We evidence that the literature regarding CNNs still misses more studies discussing educational problems faced by Global South students, considering both teaching and learning perspectives. Such a population cannot be neglected during experiments due to specific educational weaknesses (for example, basic skills) demanding personalized solutions. • A systematic literature review of 133 published papers. • China covered most publications, followed by India. • There is a research gap regarding using CNNs in some regions of the Global South. • The main educational context with CNN applications is students' performance. [ABSTRACT FROM AUTHOR]

Summary: The negative environmental impacts of burning fossil fuels have forced the energy research community seriously to consider renewable sources, such as naturally available solar energy. This paper provides an overview of solar thermoelectric (TE) cooling systems. Thus, this review presents the details referring to TE cooling parameters and formulations of the performance indicators and focuses on the development of TE cooling systems in recent decade with particular attention on advances in materials and modeling and design approaches. Additionally, the TE cooling applications have been also reviewed in aspects of electronic cooling, domestic refrigeration, air conditioning, and power generation. Finally, the possibility of solar TE cooling technologies application in “nearly zero” energy buildings is briefly discussed, and some future research directions are included. This research shows that TE cooling systems have advantages over conventional cooling devices, including compact in size, light in weight, high reliability, no mechanical moving parts, no working fluid, being powered by direct current, and easily switching between cooling and heating modes. [ABSTRACT FROM AUTHOR]

• Bibliometric analysis revealed author / institute contributions and hotspots. • Most of the constructed wetlands distributed in the east of 'Hu Huanyong Line'. • Large scale construction wetlands application in recent years was increasing. Constructed wetlands (CWs) have been introduced to and developed in China for environmental engineering over the most prosperous three decades (1990–2020). To study the origin, development process, and future trend of CWs, this review summarized a wide range of literatures between 1990 and 2020 by Chinese authors. Firstly, the publication number over years, research highlights, and the author contributions with the most published papers in this field were conducted through bibliometric analysis. Secondly, the most principal components of CWs, substrates and macrophytes were summarized and analyzed. Thirdly, the typical application cases from traditional CWs, pond systems to combined pond-wetland systems were presented. In China, CWs were predominately distributed in the east of the so-called 'Hu Huanyong Line'. Therefore CWs were limited by the socio-economic level and climatic conditions. It is unquestionable that the overall level of China's CWs has improved significantly, and one of the most prominent features has started towards the plural pattern development. There has been a trend of large-scale or low-cost CW application in the recent years. However, lifecycle research and management are required for better strategies in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper presents a detailed analysis of how future climate change may affect water availability in a typical arid endorheic river basin, the Heihe River basin (HRB), in northwest China. The analysis is based on the improved Soil Water Assessment Tool (SWAT), which is calibrated and validated with historical streamflow data from the upper HRB and is used to predict future hydrological responses. Six general circulation models (GCMs), under two emission scenarios (RCP4.5 and RCP8.5), are downscaled to construct future climate change scenarios. The results suggest that the climate of the upper HRB will likely become warmer and wetter in the near future (2021-50), with the largest increase in precipitation occurring in the summer. Correspondingly, the basinwide evapotranspiration, snowmelt, and runoff are projected to increase over the same period. The mean temperature in the near future is projected to rise, relative to the recent 30 years (1981-2010), by 1.2°-1.7°C under scenario RCP4.5 and by 1.4°-2.1°C under scenario RCP8.5. The mean precipitation is projected to increase by 10.0%-16.6% under scenario RCP4.5, and by 10.5%-22.0% under scenario RCP8.5. The mean values of evapotranspiration, snowmelt, and runoff are expected to increase by 14.2%, 4.3%, and 11.4%, respectively, under scenario RCP4.5 and to increase by 18.7%, 5.8%, and 12.8%, respectively, under scenario RCP8.5. Though the model simulations forecast an increase in streamflows in the headwater region of the HRB, future water availability varies significantly over space and time. The findings of this study will help to frame more effective water management strategies for the HRB under changing climatic conditions. [ABSTRACT FROM AUTHOR]

Northeast China (NEC) is one of the major agricultural production areas in China, producing about 30% of China's total maize output. In the past five decades, maize yields in NEC increased rapidly. However, farmer yields still have potential to be increased. Therefore, it is important to quantify the impacts of agronomic factors, including soil physical properties, cultivar selections, and management practices on yield gaps of maize under the changing climate in NEC in order to provide reliable recommendations to narrow down the yield gaps. In this study, the Agricultural Production Systems Simulator (APSIM)-Maize model was used to separate the contributions of soil physical properties, cultivar selections, and management practices to maize yield gaps. The results indicate that approximately 5%, 12%, and 18% of potential yield loss of maize is attributable to soil physical properties, cultivar selection, and management practices. Simulation analyses showed that potential ascensions of yield of maize by improving soil physical properties PAY s, changing to cultivar with longer maturity PAY c, and improving management practices PAY m for the entire region were 0.6, 1.5, and 2.2 ton ha−1 or 9%, 23%, and 34% increases, respectively, in NEC. In addition, PAY c and PAY m varied considerably from location to location (0.4 to 2.2 and 0.9 to 4.5 ton ha−1 respectively), which may be associated with the spatial variation of growing season temperature and precipitation among climate zones in NEC. Therefore, changing to cultivars with longer growing season requirement and improving management practices are the top strategies for improving yield of maize in NEC, especially for the north and west areas. [ABSTRACT FROM AUTHOR]

Ethnopharmacology relevance: Dichondra repens J.R.Forst. and G.Forst (DRF; Convolvulaceae, called Matijin in Chinese), has been traditionally used to treat jaundice, bacillary dysentery, urinary tract infection, edema, contusions, and strains and sprains based on traditional Chinese medicine (TCM) concepts. Aim of study: This paper intends to provide a comprehensive and critical analysis of research on DRF focusing on a relationship between traditional uses and pharmacological effects, evaluating the therapeutic potential of this plant. Methods: Relevant data on DRF were retrieved from available databases. Results: The heat-clearing and detoxifying, and removing the phlegm and turbid urine effects of DRF are linked to its anti-hepatitis B virus (HBV), anti-inflammatory, and hepatoprotective activities. Especially, the hepatoprotective effects of DRF are mainly based on anti-HBV activities of phenylalanine dipeptides Matijin-Su (MTS) and its derivatives derived from this plant. Further, a phase I anti-HBV clinical trial of a candidate compound named bentysrepinine (Y101, Chinese name Tifentai) has been completed. Also, anti-tumor, analgesic, and antibacterial properties have been reported in the extracts and compounds from DRF. Although pharmacy, pharmacodynamics, toxicology, and pharmacokinetics of bentysrepinine have been systemically reported, no studies have reported chemistry, safety, pharmacology of other compounds or extracts systemically. Conclusion: Phenylalanine dipeptide compounds are main components and MTS is a characteristic substance of DRF. The main pharmacological effect of DRF is anti-HBV activity, which is coherent with the traditional use of this plant in China. Except bentysrepinine, few studies have been conducted on toxicities of the extracts or compounds from DRF. Thus, it is still necessary to evaluate safety, chemistry, pharmacology of the extracts or compounds from DRF regarding the link between traditional uses and modern applications before the future clinical trials. Bacterial sepsis, cholecystitis and tumors may be prior therapeutic targets of this plant in the future. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate the literature for research trends on cerium oxide from 1990 to 2020 and identify gaps in knowledge in the emerging application(s) of CeONP. Bibliometric methods were used to identify themes in database searches from PubMed, Scopus and Web of Science Core Collection using SWIFT-Review, VOSviewer and SciMAT software programs. A systematic review was completed on published cerium oxide literature extracted from the Scopus database (n = 17,115), identifying themes relevant to its industrial, environmental and biomedical applications. A total of 172 publications were included in the systematic analysis and categorized into four time periods with research themes identified; "doping additives" (n = 5, 1990–1997), "catalysts" (n = 32, 1998–2005), "reactive oxygen species" (n = 66, 2006–2013) and "pathology" (n = 69, 2014–2020). China and the USA showed the highest number of citations and publications for cerium oxide research from 1990 to 2020. Longitudinal analysis showed CeONP has been extensively used for various applications due to its catalytic properties. In conclusion, this study showed the trend in research in CeONP over the past three decades with advancements in nanoparticle engineering like doping, and more recently surface modification or functionalization to further enhanced its antioxidant abilities. As a result of recent nanoparticle engineering developments, research into CeONP biological effects have highlighted its therapeutic potential for a range of human pathologies such as Alzheimer's disease. Whilst research over the past three decades show the versatility of cerium oxide in industrial and environmental applications, there are still research opportunities to investigate the potential beneficial effects of CeONP in its application(s) on human health. [ABSTRACT FROM AUTHOR]

In the automotive and transportation sectors, technological advancements and innovations aim to reduce fuel consumption and CO2 emissions of vehicles. In vehicles, a significant portion of fuel energy is wasted in heat, vibrations, and frictional losses. The vibration energy from vehicle suspension systems is always wasted in heat and can be utilized for useful purposes. Many researchers have designed various regenerative shock absorbers (RSA) to transform vibration energy into electrical energy that can charge electric vehicles' batteries and power low-wattage devices. The present work focuses on an in-depth summary of rotary, hydraulic, and linear electromagnetic RSA. Also, the applications of regenerated energy and technical challenges are discussed. In RSA, the maximum energy harvesting, and ride comfort of the vehicle cannot be achieved simultaneously. The weight of RSA may increase due to the integration of some additional components compared with conventional shock absorbers. It is necessary to examine the impact of weight on the vehicle's road handling and ride comfort. The hydraulic RSAs have low energy harvesting efficiency, so they are not suitable for lightweight vehicles despite their higher energy harvestability than rotary and linear RSAs. The bibliometric analysis is conducted using the visualization of similarities (VOS) viewer to visualize the contributing authors and countries and specify the research themes. The articles are collected from the Web of Science using keywords related to energy harvesting from 2000 to 2021. Authors from China are more productive than others, with the highest number of publications related to the energy-harvesting from RSAs in 2019. [ABSTRACT FROM AUTHOR]

Recent reports show air pollutant magnetite nanoparticles (MNPs) in the brains of people with Alzheimer's disease (AD). Considering various field applications of MNPs because of developments in nanotechnology, the aim of this study is to identify major trends and data gaps in research on magnetite to allow for relevant environmental and health risk assessment. Herein, a bibliometric and systematic analysis of the published magnetite literature (n = 31 567) between 1990 to 2020 is completed. Following appraisal, publications (n = 244) are grouped into four time periods with the main research theme identified for each as 1990–1997 "oxides," 1998–2005 "ferric oxide," 2006–2013 "pathology," and 2014–2020 "animal model." Magnetite formation and catalytic activity dominate the first two time periods, with the last two focusing on the exploitation of nanoparticle engineering. Japan and China have the highest number of citations for articles published. Longitudinal analysis indicates that magnetite research for the past 30 years shifted from environmental and industrial applications, to biomedical and its potential toxic effects. Therefore, whilst this study presents the research profile of different countries, the development in research on MNPs, it also reveals that further studies on the effects of MNPs on human health is much needed. [ABSTRACT FROM AUTHOR]

This paper presents an extensive review of experimental, numerical, and numerical-experimental studies focused on compiling different aspects that lead to improved PTSC performance using the different electronic base sources during the last four decades. Different applications and future research prospects have also been presented, guiding the researchers that focus on developing new working fluids, receiver configurations, applications, among other aspects for PTSC performance enhancement. Experimental studies reveal that the combination of nanofluids and turbulators leads to the best improvement in PTSC thermal efficiency, followed by the use of internal fins and nanofluids only. Numerical studies affirmed that fin inserts have a more significant influence on heat transfer than nanofluids, but its main drawback is that it has a cost increase of 5%. The dispersion of Cu and CuO in the base fluid showed a remarkable increase in the heat transfer coefficient than other nanoparticles. Therefore, they are the best options to improve the PTSC's performance. Numerical-experimental studies reveal that the tube with an internal annular porous combined with the nanofluid Al 2 O 3 /Synthetic oil showed the best increase in thermal efficiency with a value that varies from 8% to 15%. Electronic analysis of publications focused on improving the PTSC's performance shows that China participates with 25%, followed by India with 11%. The PTSC applications proved that it is ideal for electrical energy stability and less dependent on limited fossil fuel reserves. Furthermore, more experimental studies are required to mature nanofluids' application and new receiver tube configurations on an industrial scale. • Different ways to improve PTSC performance over the last 4 decades was reviewed. • Experimental and numerical studies to improve PTSC thermal performance are presented. • Nanofluids, PTSR, and numerical models are described with current challenges. • The use of nanofluids with turbulators is the best option to improve PTSC performance. • This review can help to identify the aspects to be considered in future developments. [ABSTRACT FROM AUTHOR]

With people's awareness of environmental protection, the requirement of eco‐quality is increasingly demanding, particularly a more profound reflection in the field of materials. Polylactic acid (PLA) is a hopeful biodegradable thermoplastic material while its adverse nature restricts the practical applications. In this work, a one‐step reactive extrusion method was adopted to improve some properties of PLA by melt blending with some active additives, including commercial epoxy‐based chain extender, that is, ADR4468 of BASF, Germany; thermoplastic polyurethane thermoplastic polyurethane (TPU) elastomer, that is, DN‐5380 of Dawn, China, and mineral nucleating agent talc, that is, AH250CL of Aihai, China. Their influences on mechanical properties and crystallization behaviors of PLA were explored, and the detailed mechanisms were also discussed. It is found that ADR chain extender played a key role in improving the strength and rigidity of the composites, and methylenediphenyl diisocyanate type TPU elastomer could significantly enhance the toughness and ductility of PLA materials, while talc had a positive impact on regulating the cooling crystallization behavior of PLA. In particular, only trace ADR4468 (0.4 wt%) could effectively enhance its tensile and flexural strengths of neat PLA by 6.3% and 13.4%, respectively. Reactive polyurethane with 5 wt% significantly improved its elongation at break by 36.5%. The micro‐sized talc‐nucleating agent enhanced the cooling crystallization degrees to 24.7% from 4.8% for PLA blended with trace chain extender. The analysis results indicated that the functional group reactions between the active additives and PLA played key roles in improving the related properties. The output has certain reference values for PLA modification strategy, and will pave a route for endowing PLA materials with specific and required nature. [ABSTRACT FROM AUTHOR]

ABSTRACT For the first time, the main characteristics of the polymeric materials are considered for understanding their possible application in ecological sand-fixing. In this investigation, two emulsions, named as E2, a poly(vinyl acetate) emulsion, and E7, a vinyl acetate-ethylene copolymer emulsion, have been selected for a series of tests related to the practical requirements for ecological sand-fixing. Besides the sand-fixing properties and the thermal aging and freeze-thaw stabilities of the emulsions, their effects in increasing the growth of both microbes and plants in sandy lands have been evaluated by field experiments in Kerqin Sandy Land of China, and the relationship between the performance and structure of the two emulsions has also been described. The experimental results show that both emulsions could significantly improve the compressive strength of treated sand and could withstand the changes in temperature of the Kerqin Sandy Land. However, different effects were exhibited in promoting the growth of microbes, in facilitating the accumulation of organic fertilizer and soluble salt, and in increasing the crop yield. All of the differences are attributed to their different molecular chain structures. These findings suggest that the structure of a polymeric emulsion should be the first consideration for the materials used in ecological sand-fixing, and ecological sand-fixing is a successful method for the stabilization of sandy land and the restoration of desertified land in semiarid regions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44102 [ABSTRACT FROM AUTHOR]

Many efforts have been taken to investigate aerosol-cloud interactions from space, but only a few studies have examined the response of vertical cloud structure to aerosol perturbations. Three-dimensional cloud climatologies of eight different cloud types identified from the CloudSat level-2 cloud product during the warm season (May-September) in 2008-10 over eastern China were first generated and analyzed. Using visibility as a proxy for cloud condensation nuclei, in combination with satellite-observed radar reflectivity, normalized contoured frequency by altitude diagrams of the differences in cloud radar reflectivity Z profiles under polluted and clean conditions were constructed. For shallow cumulus clouds (shallow Cu) Z tends to be inhibited, and it is enhanced in the upper layers for deep cumulus (deep Cu), nimbostratus (Ns), and deep convective clouds (DCC) under polluted conditions. Overall, analyses of the modified center of gravity (MCOG) and cloud-top height (CTH) also point to a similar aerosol effect, except for the nonsignificant changes in MCOGs and CTHs in deep Cu. The impacts of environmental factors such as lower-tropospheric stability and vertical velocity are also discussed for these types of clouds. Although consistent aerosol-induced elevations in MCOGs and CTHs for Ns and DCC clouds are observed, the effect of meteorology cannot be completely ruled out, which merits further analysis. [ABSTRACT FROM AUTHOR]

Future changes in floods and water availability across China under representative concentration pathway 2.6 (RCP2.6) and RCP8.5 are studied by analyzing discharge simulations from the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP) with the consideration of uncertainties among global climate models (GCMs) and hydrologic models. Floods and water availability derived from ISI-MIP simulations are compared against observations. The uncertainties among models are quantified by model agreement. Only model agreement >50% is considered to generate reliable projections of floods and water availability and their relationships with climate change. The results show five major points. First, ISI-MIP simulations have acceptable ability in modeling floods and water availability. The spatial patterns of changes in floods and water availability highly depend on the outputs of GCMs. Uncertainties from GCMs/hydrologic models predominate the uncertainties in the wet/dry areas in eastern/northwestern China. Second, the magnitudes of floods throughout China increase during 2070-99 under RCP8.5 relative to those with the same return periods during 1971-2000. The increase rates of larger floods are higher than those of the smaller ones. Third, water availability decreases/increases in southern/northern China under RCP8.5, but changes negligibly under RCP2.6. Fourth, more severe floods in the future are driven by more intense precipitation extremes over China. The negligible change in mean precipitation and the increase in actual evapotranspiration reduce the water availability in southern China. Fifth, model agreements are higher in simulated floods than water availability because increasing precipitation extremes are more consistent among different GCM outputs compared to mean precipitation. [ABSTRACT FROM AUTHOR]