•The average plate waste of Beijing university students is 73.7 g/cap/meal.•Grade level and financial condition significantly related to plate waste.•Dietary preference and personal appetite are ...first considerations when ordering food.•Guilt and considering saving food a positive lifestyle result in waste reduction.•The environmental footprints caused by plate waste were considerable.
Food waste in China has gained increased attention in recent years due to its rising quantity and adverse environmental, economic, and societal impacts. As university students are an indispensable part of Chinese society and will become the backbone of China’s future sustainable development, their dietary habits and food-wasting behaviors are of both societal and scientific relevance. In this study, we combined direct weighing, questionnaire surveys, and regression analysis to quantify the plate waste of university students in Beijing and identified key influencing factors, based on 551 observations from 6 sample universities. We also evaluated the environmental impacts of university plate waste from the perspective of nitrogen, phosphorus, carbon, and ecological footprints. The results showed that the average plate waste generated by university students in Beijing was 73.7 g/cap/meal in 2018, with staple foods and vegetables contributing the most. There were apparent correlations between plate waste and both grade level and financial condition: lower educational levels and higher disposable incomes both led to more food waste. Male students wasted significantly less staple food than female students. Students’ self-report difficulty of avoiding waste significantly related to plate waste. Dietary preference and personal appetite were prominent considerations when students ordered food, corresponding to problems in food quality and quantity at university canteens. Attitudes most likely to reduce plate waste included a sense of guilt and considering saving food a positive lifestyle. The estimated annual environmental footprints caused by plate waste were considerable, mainly deriving from staple foods and meats.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
CoCrFeNiZr0.3 is a two-phase coexisting (Laves + FCC) high-entropy alloy with high strength, excellent corrosion resistance, and thermal stability. However, the inhomogeneous distribution of the ...eutectic structure among the dendrites has a detrimental effect on the coordinated deformation of the material. The current study shows that the grain size, weave structure, and second phase distribution of high-entropy alloys can be significantly changed by thermal deformation, which affects the mechanical and physical properties, as well as the chemical stability of the alloys. In this study, the thermal deformation behavior of CoCrFeNiZr0.3 biphasic hypoeutectic high-entropy alloy was investigated using a Gleeble-3500 thermal simulation tester under the conditions of deformation temperature of 950–1100 °C and deformation rate of 0.001–1 s−1. The results show that CoCrFeNiZr0.3 high-entropy alloy has higher deformation activation energy, which means its deformation resistance is larger. In addition, the microstructure with finer grain size and uniform distribution of Laves phase can be obtained by EBSD analysis after compression at 1000 °C and 0.01 s−1.
In this study, the Mo0.5NbTiZrTax (x = 0.3, 0.5, 0.7) HEAs obtained by arc melting were controlled by the change of Ta content. The microstructure, the wear properties, and the corrosion resistance ...of the alloys were studied systematically. The results revealed that the alloys have the BCC (major) phase + BCC (minor) phase structure. At the same time, the increase in Ta content promotes the refinement of grains and the formation of sub-grains with gradually random orientation at grain boundaries but suppresses the randomization of crystal orientation. This also enriched the defect structure inside the alloys, further induced the formation of Zr-rich second phase particles, high-density stacking fault structures, and disordered Zr-rich BCC phases. The increase in Ta content significantly improved the wear properties of the alloys, which is mainly ascribed to the presence of the tough BCC phase and the combined effects of solid solution strengthening, second phase strengthening, fine grain strengthening, lattice distortion effect, and stacking fault strengthening. The electrochemical measurements confirm that the overall corrosion resistance of the alloys shows a trend of first increasing and then decreasing with the increase of Ta content due to the formation of micro batteries between the second phase rich in Zr as the anode and dendrites.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
ObjectivesWe conducted a systematic review and meta-analysis to determine the efficacy of non-conventional synthetic disease-modifying antirheumatic drug (ncs-DMARD) strategies on patients with ...rheumatoid arthritis (RA)-associated interstitial lung disease (ILD).MethodsPubMed, EMBASE, the Cochrane Library and Web of Science were searched for relevant articles from inception to 1 June 2022. The results obtained from the analysis were expressed as mean difference (MD), effect size and 95% CI.ResultsA total of 17 studies, including 1315 patients with RA-ILD, were eligible. The ncs-DMARDs included abatacept, rituximab, tocilizumab, tumour necrosis factor and Janus kinase inhibitors. Compared with the baseline, there were no significant changes in forced vital capacity (FVC), forced expiratory volume in the first second (FEV1) and diffusion lung capacity for carbon monoxide (DLCO) values in the pooled data after ncs-DMARD treatment (alone or combined with conventional therapy) (p=0.36 for FVC; p=0.96 for FEV1 and p=0.46 for DLCO). Of note, FVC was obviously increased in rituximab subgroup (MD=−4.62, 95% CI −8.90 to −0.33, p=0.03). Also, high-resolution CT non-progression rate and fatality rate due to ILD progression in patients with RA-ILD were 0.792 (95% CI 0.746 to 0.834, p=0.015) and 0.049 (95% CI 0.035 to 0.065, p=0.000), respectively.Conclusionncs-DMARDs alone or combined with conventional therapy might be an optimal and promising treatment for stabilising or improving ILD in patients with RA-ILD.PROSPERO registration numberCRD42022356816.
Sustainable development is a pressing worldwide issue and is particularly a challenge in developing countries. China, as the world's largest developing country, has recently undergone a paradigm ...shift in terms of development strategy and proposed a new sustainable policy in 2015, which promotes the coordinated progress of industrialization, informatization, urbanization, agricultural modernization, and greenization (“Five Modernizations”). Using panel data pertaining to 283 prefecture-level cities for 2006–2015, we assessed the development level of the “Five Modernizations” and investigated the trends, patterns, and determinants of the “Five Modernizations” with respect to scale and economic level. The results show that the “Five Modernizations” underwent significant growth during the study period. Cities with the highest coordinated development level are mainly located in the downstream areas of the Yellow River, Yangtze River Delta, and Pearl River Delta. The agglomeration degree for the coordinated development level is decreasing. Cities of different spatial and economic scales show various coordinated development level patterns. For scales, mega cities appear to be more “sufficient”, with higher comprehensive development level, while middle and small cities show more “balanced” development, with higher coupling degrees. Further, a positive spillover effect is observed from Mega cities to their neighboring cities. There exists an inverted U-shaped relationship between coordinated development level and economic level, where the most developed cities have passed the vertex and lie on the downtrend. Our results provide insights into the sustainable development pathways and patterns for policy makers in China and other developing countries.
•Coordinated development of “Five Modernizations” rose significantly.•“Five Modernizations” is deeply affected by city's economic level.•Inverse U shape appeared between economic growth and “Five Modernizations”.•Pursuit of fast development and neglect of balance lead cities unsustainably•High-level “Five Modernizations” cities show spillover effect on surrounding cities.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
As the largest CO2 emitter in the world, China is facing significant challenges in CO2 mitigation. In the search for low-carbon development and industrial upgrading, the Beijing-Tianjin-Hebei (BTH) ...region represents an experimental plot for all of China. In this study, we employed a comprehensive analytical framework to investigate the changing pattern of CO2 emissions in the BTH region, where large-scale industrial structural changes are happening; the results of this study provide a critical reference for regions facing the dual tasks of industrial transitions and environmental protection. The results indicate that industrial structural changes have helped diminish mounting CO2 emissions in the BTH region; however, the extent of the effect differs among the provinces involved. Improvements in technology and organization level in the fastest growing sectors, such as machinery manufacturing and service industries, have helped to curb CO2 emissions significantly. However, industrial structural changes have failed to narrow the CO2 emission gaps among provinces in the region. Being in different phase of development and possessing various resource endowments, the provinces in the BTH region have followed a diversified path of industrial upgrading and have emerged as a region with explicit labor divisions and supply chains. On one hand, this intensifies regional CO2 emission differences, and on the other, it has allowed policymakers to promote more customized decarbonizing plans.
•A framework to decode CO2 emission patterns was established.•Two entirely different CO2 emission patterns were observed in BTH region.•Rapid growth in less resource-intensive industries was observed.•Improvements in the fastest growing sectors helped curb CO2.•Decarbonizing patterns differed among provinces in BTH region.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Photodynamic therapy (PDT) and chemodynamic therapy (CDT) are promising tumor treatments mediated by reactive oxygen species (ROS), which have the advantages of being minimally invasive. However, the ...hypoxia of tumor microenvironment and poor target ability often reduce the therapeutic effect. Here we propose a tumor targeted nanoplatform PCN‐224@Co3O4‐HA for enhanced PDT and synergistic CDT, constructed by hyaluronate‐modified Co3O4 nanoparticles decorated metal‐organic framework PCN‐224. Co3O4 can catalyze the decomposition of highly expressed H2O2 in tumor cells to produce oxygen and alleviate the problem of hypoxia. It can also produce hydroxyl radicals according to the Fenton‐like reaction for chemical dynamic therapy, significantly improving the therapeutic effect. The cell survival experiment showed that after in vitro treatment, 4T1 and MCF‐7 cancer cells died in a large area under the anaerobic state, while the survival ability of normal cell L02 was nearly unchanged. This result effectively indicated that PCN‐224@Co3O4‐HA could effectively relieve tumor hypoxia and improve the effect of PDT and synergistic CDT. Cell uptake experiments showed that PCN‐224@Co3O4‐HA had good targeting properties and could effectively aggregate in tumor cells. In vivo experiments on mice, PCN‐224@Co3O4‐HA presented reliable biosafety performance, and can cooperate with PDT and CDT therapy to prevent the growth of tumor.
We design and synthesize a tumor targeted nanoplatform (PCN‐224@Co3O4‐HA). HA can specifically target 4T1 cells and Co3O4 can produce oxygen in situ to alleviate the hypoxic environment of the tumor. This nanosystem presents reliable biosafety performance, and can combine with PDT and CDT therapy to prevent the growth of tumor.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
In this study, CoCrFeNiAlx (x = 0.1, 0.5, 1) high-entropy alloys (HEAs) are prepared using vacuum arc melting. In order to improve the surface properties of CoCrFeNiAlx HEAs, their microstructure is ...manipulated by laser surface remelting (LSM). The microstructure, the mechanical properties, and the corrosion resistance of the HEAs before and after LSM are studied systematically. The microstructural analysis reveals that the LSM-samples contained either a single FCC phase (CoCrFeNiAl0.1 and CoCrFeNiAl0.5) or a mixture of BCC + B2 phases (CoCrFeNiAl1) with refined grains. Moreover, BCC precipitates and a spherical nano-dispersed phase (B2) are detected in the surface layer of CoCrFeNiAl0.5 and CoCrFeNiAl1, respectively. The mechanical properties of CoCrFeNiAlx alloys are found to be significantly enhanced after LSM, which is mainly ascribed to the generation of the BCC phase, dislocation reinforcement and grain-strengthening as well as precipitation hardening. The electrochemical measurements confirm that all samples (after LSM) have a positive potential and a lower current density in 3.5 wt% NaCl solution compared to the untreated sample. The results indicate that LSM can help homogenize the structure and improve the properties of CoCrFeNiAlx HEAs.
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•LSM treatment was conducted on the surface of as-cast CoCrFeNiAlx (x = 0.1,0.5,1) HEAs and the grains of each component were refined obviously.•A 365.2–1200 μm thick remelted layer was formed.•After LSM, abundant dislocation structures appeared on the surface, and spherical nano dispersed B2 phase was found in Al1.•Surface microhardness, wear and corrosion resistance were improved evidently.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Laser remelting (LR) treatment was used to regulate the microstructure of AlCoCrFeNiTax high-entropy alloys prepared by vacuum arc melting, and the microstructure and properties of the alloys before ...and after LR treatment were analyzed. The original AlCoCrFeNiTax alloys have typical dendritic morphology and the addition of Ta element promoted the formation of a Laves phase, gradually changing the alloys from two phase (BCC + B2) to three phase (BCC + B2 + Laves phase). After LR treatment, the grains were significantly refined, elemental segregation was alleviated, and a dense remelting layer with a thickness of 1200–1600 µm was formed on the surface of the alloy. In addition, the hardness and wear resistance of the alloys were improved with increasing Ta content and LR treatment, mainly caused by the combined effects of solution strengthening, second phase strengthening and fine grain strengthening. At the same time, the corrosion resistance of the alloys before and after LR treatment in 3.5 wt% NaCl solution is significantly improved by a stable Ta2O5 and TaO2 passivation films and the formation of a dense uniform remelting layer.
•Refractory element was added and LR treatment was conducted on the surface of AlCoCrFeNiTax high entropy alloy.•After LR treatment, elemental segregation on the alloy surface is alleviated and the alloy grains are refined.•A remelted layer of about 1200–1600 µm thickness was formed on the alloy surface after LR treatment.•The hardness and wear resistance of the alloys were improved with increasing Ta content and LR treatment.•The corrosion resistance of the alloys in 3.5 wt% NaCl solution is improved by passivation film and remelted layer.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In order to further improve the oxidation resistance of CoCrFeNiAlx (x = 0.1, 0.5, and 1) high entropy alloys (HEAs), the surface of CoCrFeNiAlx prepared by vacuum arc melting is controlled by laser ...surface remelting (LSM) and the high-temperature oxidation properties of CoCrFeNiAlx before and after LSM is systematically studied. The results revealed that, with the increase of Al content, the parabolic velocity constant kp value gradually decreased after LSM treatment. Moreover, CoCrFeNiAl0.1 formed a continuous Cr2O3 oxide layer, CoCrFeNiAl0.5 formed an outer layer of Cr2O3 oxide film and an inner layer of Al2O3 precipitation, and CoCrFeNiAl1 formed a uniform and dense Al2O3 oxide layer on the entire area. After 100 h of oxidation, the oxide film thickness of three alloys is around 5 µm, 4 µm, and 3 µm, respectively. The improvement in oxidation resistance after LSM can be ascribed to the formation of a dense re-melted layer, uniform distribution of the elements, refinement of the re-melted layer.
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•LSM treatment was conducted on the surface of as-cast CoCrFeNiAlx (x = 0.1,0.5,1) high entropy alloy.•The oxidation kinetics curves of CoCrFeNiAlx HEAs (x = 0.1, 0.5 and 1) indicated that all HEAs are in the transitional stage during the initial period of oxidation, showing a parabolic behavior.•The parabolic velocity constant value (kp) gradually decreased after LSM. Moreover, the increase of Al content also decreased the oxidation rate of the samples.•After LSM, CoCrFeNiAl0.1 formed a continuous and dense Cr2O3 oxide layer, and CoCrFeNiAl0.5 alloy formed a double-layer oxide on the surface.•After LSM, the CoCrFeNiAl1 alloy formed a uniform and single-phase Al2O3 oxide layer, which became thick and uniform with time.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
