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Microplastic pollution control has always been a thorny problem all over the world. Magnetic porous carbon materials have shown a good development prospect in microplastic adsorption due to their excellent adsorption performance and easy magnetic separation from water. However, the adsorption capacity and rate of magnetic porous carbon on microplastics are still not high, and the adsorption mechanism is not fully revealed, which hinders its further development. In this study, magnetic sponge carbon was prepared using glucosamine hydrochloride as the carbon source, melamine as the foaming agent, iron nitrate and cobalt nitrate as the magnetizing agents. Among them, Fe-doped magnetic sponge carbon (FeMSC) exhibited excellent adsorption performance for microplastics due to its sponge-like morphology (fluffy), strong magnetic properties (42 emu/g) and high Fe-loading (8.37 Atomic%). FeMSC could adsorb to saturation within 10 min, and the adsorption capacity of polystyrene (PS) reached as high as 369.07 mg/g in 200 mg/L microplastic solution, which was almost the fastest adsorption rate and highest adsorption capacity reported so far in the same condition. The performance of the material against external interference was also tested. FeMSC performed well in a wide pH range and different water quality, except in the strong alkaline condition. This is because the surface of microplastics and adsorbents will have many negative charges under strong alkalinity, significantly weakening the adsorption. Furthermore, theoretical calculations were innovatively used to reveal the adsorption mechanism at the molecular level. It was found that Fe-doping could form chemisorption between PS and the adsorbent, thereby significantly increasing the adsorption energy between the adsorbent and PS. The magnetic sponge carbon prepared in this study has excellent adsorption performance for microplastics and can be easily separated from water, which is a promising microplastic adsorbent.
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Biomass-derived porous carbon materials are potential adsorbents for VOCs. In this work, biomass-derived nitrogen-doped hierarchical porous carbons (NHPCs) were synthesized by a one-step pyrolysis activation combined with nitrogen doping method from several biomass wastes (corn straw, wheat stalk, bamboo, pine, and corncob). NHPCs have a hierarchical porous structure with micro-meso-macropores distribution, nitrogen doping, large specific surface area, and pore volume. The corncob derived carbon (NHPC-CC) has the best activation result as analyses showed that a lower ash content and higher total cellulose composition content of the biomass result in a better pore activation effect. Single and multi-component dynamic adsorption tests of typical VOCs (benzene, toluene, and chlorobenzene) were conducted on NHPCs in laboratory conditions (â¼500 ppm). Promising VOC adsorption capacity and great adsorption kinetics with low mass transfer resistance were found on NHPCs. Correlation analysis showed that the high VOC adsorption capacity and great adsorption kinetics can be attributed to the large surface area of micro-mesopores and the mass transfer channels provided by meso-macropores respectively. The competitive dynamic adsorption tests revealed that the VOC with lower saturated vapor pressure has more adsorption sites on the surface of micro-mesopores and stronger adsorption force, which results in the higher adsorption capacity and desorption caused by substitution reaction in VOCs competitive adsorption process. In detail, the process of toluene and chlorobenzene competitive adsorption was described. Besides, well recyclability of NHPC-CC was revealed as the VOCs adsorption capacity reductions were less than 10% after four adsorption-desorption cycles. All studies showed that the NHPC-CC could be potential adsorbent for VOCs in industrial process.
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Carbono , Compuestos Orgánicos Volátiles , Carbono/química , Adsorción , Porosidad , Biomasa , Nitrógeno , ToluenoRESUMEN
The coal combustion produces a large amount of pollutants such as organic compounds pollutants (such as VOCs, SVOCs) and conventional pollutants (such as SO2, NOx) which need to be controlled in coal-fired plants. Currently, there have been mature emission control technologies for conventional pollutants in coal-combustion flue gas. The complicated conditions of flue gas will have great effects on the property of VOCs adsorbents. Thus, high-quality adsorbents with great adsorption properties and selectivity of VOCs are urgently needed. In this work, a biomass-derived hierarchical porous carbon (HPC-A) with high adsorption capacity (585 mg/g) and great selectivity of toluene was proposed. Analyses through the competitive adsorption tests between toluene and SO2 indicated that the pore size distributions of adsorbents dominate the adsorption capacity and selectivity. The ultramicropores (< 0.7 nm) determine the SO2 adsorption capacity and promote the SO2 adsorption selectivity, while the micropores of 0.7 ~ 2 nm and mesopores are beneficial for toluene adsorption. Intriguingly, the SO2 molecules can promote the toluene adsorption kinetics on hierarchical porous carbons through occupying ultramicropores when competitive adsorption. Besides, we indicated the mechanism of adsorption capacity, selectivity, and kinetics of toluene and SO2, and great reusability of HPC-A was found through toluene cyclic adsorption tests. The HPC-A could be a potential adsorbent for VOCs removal from coal-combustion flue gas.
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Contaminantes Ambientales , Tolueno , Adsorción , Carbono , Carbón Mineral , PorosidadRESUMEN
After the severe initial insults of acute kidney injury, progressive kidney tubulointerstitial fibrosis may occur, the peritubular capillary (PTC) rarefaction plays a key role in the disease progression. However, the mechanisms of PTC damage were not fully understood and potential therapeutic interventions were not explored. Previous studies of our research team and others in this field suggested that bone marrow-derived mesenchymal stem cells (BMSCs) transplanted into the AKI rat model may preserve the kidney function and pathological changes. In the current study, with the ischemia/reperfusion AKI rat model, we revealed that BMSCs transplantation attenuated the renal function decrease in the AKI model through preserving the peritubular capillaries (PTCs) function. The density of PTCs is maintained by BMSCs transplantation in the AKI model, detachment and relocation of pericytes in the PTCs diminished. Then we established that BMSCs transplantation may attenuate the renal fibrosis and preserve the kidney function after AKI by repairing the PTCs. Improving the vitality of pericytes, suppressing the detachment and trans-differentiation of pericytes, directly differentiation of BMSCs into pericytes by BMSCs transplantation all participate in the PTC repair. Through these processes, BMSCs rescued the microvascular damage and improved the density of PTCs. As a result, a preliminary conclusion can be reached that BMSCs transplantation can be an effective therapy for delaying renal fibrosis after AKI.
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Lesión Renal Aguda/complicaciones , Endotelio Vascular/citología , Fibrosis/terapia , Enfermedades Renales/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Pericitos/citología , Animales , Fibrosis/etiología , Fibrosis/metabolismo , Fibrosis/patología , Enfermedades Renales/etiología , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
Being a node of the energy-water consumer and carbon dioxide (CO2) emitter, the household is one key sector to pilot integrated energy-carbon-water (ECW) management. This study developed an integrated framework to explore China's provincial household ECW nexus as well as their drivers from the years 2000 through 2016. The absolute amount and growth rate of household energy use (HEU), household CO2 emissions (HCE), and household water use (HWU) were abstracted to reveal the dynamic characteristics of the household ECW nexus. Efficiency advance, income growth, urbanization, family size, and household number were defined to explain the changes in the household ECW nexus. This study revealed that there is a huge regional heterogeneity in China's household ECW nexus. Developed regions such as Zhejiang, Jiangsu, Guangdong, and Shanghai are the most important household ECW nexus nodes with larger amounts and growth rates of household ECW. Income growth overwhelmingly increases ECW, while efficiency advance effectively curbs its growth. Comparatively, household number, family size, and urbanization have small effects. Therefore, implementing differentiated management and focusing on the synergy of socioeconomic factors are the keys to achieving integrated household ECW management. And the analytical framework can be used to analyze ECW nexus from a sector, city, or country perspective.
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Urbanización , Agua , China , Composición FamiliarRESUMEN
As the largest contributor to production-based emissions, electricity generation sector has led to huge carbon emission transmissions. This is the first attempt to explore the latest features of carbon emission transmissions from electricity sector to the final domestic consumption of China in 2002-2015, combining MRIO-based Structural Path Analysis and transmission-based emission method. Results show that: (1) Although inter-provincial transmissions are increasing significantly, emission transmissions within intra-provincial trading are dominated. (2) 30 provinces are classified into two types, i.e., consumption centers and production centers. Both the inter-provincial transmission paths in consumption centers and production centers show the grid-level agglomeration and provincial heterogeneity. The inflow paths in consumption centers are mainly sourced from the production of Eastern China and South China, while the outflow paths for production centers are caused by the consumption in Central China, Guangdong and Jiangsu. Inter-provincial linkages are intensified and perform the feature of territorial propinquity. (3) Both intra-grid and inter-grid transmission nodes show an agglomeration trend of "electricity sector < intermediate sectors < electricity sector < consumption". These intermediate sectors include manufacture sectors, energy-intensive sectors and service sector. This paper provides policy implications on promoting low-carbon electricity cooperation across provinces and managing intermediate transmissions along supply chain.
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RATIONALE: Multiorgan/system injury was observed in severely infected coronavirus disease 2019 (COVID-19) patients, in addition to viral pneumonia. Recognizing and correcting the key and immediate dysfunctions may reduce mortality. PATIENT CONCERNS: A 66-year-old previously healthy male patient was referred to the isolation ward in Guanggu Branch of Hubei Province Maternity and Childcare Hospital with a high fever and nonproductive cough for twenty days. DIAGNOSES: Diagnosis of severe COVID-19 infectious pneumonia was established by travel history, clinical features, chest imaging, and a positive oropharyngeal swab specimen result for the severe acute respiratory syndrome coronavirus 2 RT-PCR assay. INTERVENTIONS: In addition to standard supportive care, combined inflammatory cytokine depletion therapy (double filtration plasma pheresis and tocilizumab) and convalescent plasma were administered. OUTCOMES: The patient's homeostatic parameters (blood pressure, heart rate, spontaneous respiration, SPO2, and blood gas) recovered, along with the recovery on chest imaging. All the intravenous catheters were removed. Supportive care continued for several days, and the patient was transferred to a non-ICU isolation ward. LESSONS: It is not safe to draw causal conclusions between cytokine depletion and clinical manifestation improvement with only 1 case, but this is a potential research direction in facing the COVID-19 crisis.
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Anticuerpos Monoclonales Humanizados/uso terapéutico , COVID-19/terapia , Plasmaféresis/métodos , Anciano , Anticuerpos Monoclonales Humanizados/administración & dosificación , COVID-19/complicaciones , Terapia Combinada , Citocinas , Hemodinámica , Humanos , Inmunización Pasiva , Masculino , Pandemias , Neumonía Viral/etiología , Neumonía Viral/terapia , SARS-CoV-2 , Sueroterapia para COVID-19RESUMEN
Laccases belong to ligninolytic enzymes and play important roles in various biological processes of filamentous fungi, including fruiting-body formation and lignin degradation. The process of fruiting-body development in Lentinula edodes is complex and is greatly affected by environmental conditions. In this paper, 14 multicopper oxidase-encoding (laccase) genes were analyzed in the draft genome sequence of L. edodes strain W1-26, followed by a search of multiple stress-related Cis-elements in the promoter region of these laccase genes, and then a transcription profile analysis of 14 laccase genes (Lelcc) under the conditions of different carbon sources, temperatures, and photoperiods. All laccase genes were significantly regulated by varying carbon source materials. The expression of only two laccase genes (Lelcc5 and Lelcc6) was induced by sodium-lignosulphonate and the expression of most laccase genes was specifically upregulated in glucose medium. Under different temperature conditions, the expression levels of most laccase genes decreased at 39 °C and transcription was significantly increased for Lelcc1, Lelcc4, Lelcc5, Lelcc9, Lelcc12, Lelcc13, and Lelcc14 after induction for 24 h at 10 °C, indicating their involvement in primordium differentiation. Tyrosinase, which is involved in melanin synthesis, was clustered with the same group as Lelcc4 and Lelcc7 in all the different photoperiod treatments. Meanwhile, five laccase genes (Lelcc8, Lelcc9, Lelcc12, Lelcc13, and Lelcc14) showed similar expression profiles to that of two blue light receptor genes (LephrA and LephrB) in the 12 h light/12 h dark treatment, suggesting the involvement of laccase genes in the adaptation process of L. edodes to the changing environment and fruiting-body formation. This study contributes to our understanding of the function of the different Lelcc genes and facilitates the screening of key genes from the laccase gene family for further functional research.
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Basidiomycota/genética , Proteínas Fúngicas/genética , Lacasa/genética , Secuencia de Aminoácidos , Basidiomycota/metabolismo , Carbono/metabolismo , Proteínas Fúngicas/clasificación , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Lacasa/clasificación , Lacasa/metabolismo , Monofenol Monooxigenasa/genética , Monofenol Monooxigenasa/metabolismo , Fotoperiodo , Filogenia , Regiones Promotoras Genéticas , Alineación de Secuencia , TemperaturaRESUMEN
A metal-free catalytic strategy for the facile synthesis of biologically relevant molecular architectures indolizines and imidazopyridines has been developed. The process is promoted by amine and N-heterocyclic carbene (NHC) relay catalysis via Michael addition-[3 + 2] fusion of simple azaarenes and α,ß-unsaturated aldehydes. The preparative power is demonstrated in the synthesis of anxiolytic drug saripidem via two simple one-pot operations with overall 45% yield.
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A Pd(OAc)2-catalyzed divergent synthesis of multisubstituted imidazoles and quinazolines from N-allylamidines has been developed. In the presence of oxidant O2 from air and/or a ligand and Pd(OAc)2, imidazoles were obtained. Nonetheless, under microwave (MW) irradiation in a sealed system, quinazolines as major products were produced.