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1.
Environ Sci Pollut Res Int ; 31(35): 47630-47643, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39002081

RESUMO

In the heavy industrial city of Northeast China, there has been a significant decrease in particulate matter pollution while experiencing a sharp increase in ozone (O3) pollution. However, the main influencing factors and source contributions to O3 remain unclear. Taking the case of Siping as an example, this study analyzed the spatiotemporal characteristics, assessed local source contributions to O3, and revealed regional transmission effects using numeric simulation and statistical methods. Temporally, higher O3 concentrations were observed in summer and the afternoon, with hourly peaks up to 254 µg/m3. Spatially, O3 pollution was mainly contributed by background concentrations (34.52%), external transport (34.50%), and local emissions (30.98%) during the case study period (June 11-18, 2021). Among the local emission sources, biological emissions, the industrial sector, and the traffic sector accounted for 35.30%, 32.09%, and 23.58% of the O3 concentration, respectively. For regional atmospheric transmission, high O3 pollution was accompanied by wind from the southwest directions, and the trajectory of air mass transport suggests that eastern Mongolia, the Korean Peninsula, and its neighboring regions contribute to O3 pollution. Furthermore, sensitivity analysis showed that O3 pollution in Siping is a co-controlled region by anthropogenic volatile organic compounds (AVOCs) and NOX, which implies control in an optimal ratio of VOCs and NOX emissions. Thus, our results highlight the importance of joint prevention and control of O3 pollution in the region, optimization of biogenic landscape ecology, and control of VOCs and NOx in both the industrial and transport sectors.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Cidades , Monitoramento Ambiental , Ozônio , Ozônio/análise , China , Poluentes Atmosféricos/análise , Material Particulado/análise , Compostos Orgânicos Voláteis/análise , Indústrias
2.
Environ Sci Pollut Res Int ; 30(11): 31895-31904, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36459322

RESUMO

With the rapid development of transportation and vehicles, the elimination of NOx and CO has highly attracted public attention. In this work, vacancy-rich CeO2 nanopencil supported CuO catalysts (CuO/CeO2-NPC) were successfully prepared for NO reduction by CO. Importantly, CeO2 with nanopencil-like shape (CeO2-NPC) have been synthesis by solvothermal method for the first time. The physicochemical properties of all samples were studied in detail by combining the means of X-ray diffraction (XRD), Raman spectroscopy, electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), H2-temperature-programmed reduction (H2-TPR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), N2 physisorption (Brunauer-Emmett-Teller), and NO and CO temperature-programmed desorption (NO-TPD and CO-TPD) techniques. Compared with CeO2 nanorods and nanoparticles supported CuO catalysts (CuO/CeO2-NR and CuO/CeO2-NP), the CuO/CeO2-NPC catalysts showed the highest catalytic activity, affording more than 90% NO conversion at 69 °C as well as excellent H2O tolerance at 150 °C, which is superior to catalysts previously reported. Characterization results indicated that the synergistic effect between the well-dispersed CuO and the CeO2 nanopencil support enables a favorable electron transfer between these components and enhances the density of surface oxygen vacancies and Cu+ species, which consequently accelerating the redox cycle. The results indicated that the morphology control of CeO2 support could be an efficient way to evidently enhance the catalytic performance for NO + CO reaction.


Assuntos
Cério , Temperatura , Cério/química , Temperatura Baixa , Cobre/química
3.
J Sports Med Phys Fitness ; 61(1): 10-17, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32878421

RESUMO

BACKGROUND: Muscle performance can be notably improved following a preloading maximal or near maximal stimulus due to the induction of postactivation potentiation, but the success of a preloading exercise in generating a postactivation potentiation response depends on the balance between fatigue and potentiation. However, the optimal warm-up strategy for sprint runners before a match may be not well established until now. METHODS: Fifteen well-trained male sprint runners performed four different warm-up protocols: warm-up with 0% body mass; warm-up with 2% body mass; warm-up with 4% body mass; warm-up with 8% body mass. The weight-bearing sandbag was tied about 3~5 cm above each ankle joint. During the 100-meter test, the time and rating of perceived exertion (RPE) in the first 30 meters, time in the first 60 meters, and time in the 100 meters were recorded, respectively. Two-high-speed digital video cameras were separately set in the sagittal planes on the left side of a line drawn at a distance of 30 m and 60 m from the start line to record the sprint motion. RESULTS: A warm-up performed with a sandbag weighted 4% of body mass could significantly improve the time and the RPE score of 100 m sprint by improving average velocity, stride frequency, average stride length, and average accelerated velocity during the sections of 0~30 m, 30~60 m and 60~100 m. This positive effect was better than that of 2% body-weigh effect. However, a warm-up performed with a sandbag weighted 8% of body mass had no significant influence on the performance of a 100 m sprint. CONCLUSIONS: Current results indicated that a warm-up performed with proper-weight(4% body mass) sandbags on the leg was beneficial to the improvement of 100 m sprint performance, and the mechanism might be that it effectively activated the main muscles and neuromuscular regulation of running and produced a better postactivation potentiation.


Assuntos
Desempenho Atlético/fisiologia , Corrida/fisiologia , Exercício de Aquecimento/fisiologia , Exercício Físico , Comportamentos Relacionados com a Saúde , Humanos , Perna (Membro)/fisiologia , Masculino , Universidades , Adulto Jovem
4.
Biol Open ; 9(5)2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32414766

RESUMO

A high-salt diet (HSD) is a major cause of many chronic and age-related defects such as myocardial hypertrophy, locomotor impairment and mortality. Exercise training can efficiently prevent and treat many chronic and age-related diseases. However, it remains unclear whether endurance exercise can resist HSD-induced impairment of climbing capacity and longevity in aging individuals. In our study, flies were given exercise training and fed a HSD from 1-week old to 5-weeks old. Overexpression or knockdown of salt and dFOXO were built by UAS/Gal4 system. The results showed that a HSD, salt gene overexpression and dFOXO knockdown significantly reduced climbing endurance, climbing index, survival, dFOXO expression and SOD activity level, and increased malondialdehyde level in aging flies. Inversely, in a HSD aging flies, endurance exercise and dFOXO overexpression significantly increased their climbing ability, lifespan and antioxidant capacity, but they did not significantly change the salt gene expression. Overall, current results indicated that a HSD accelerated the age-related decline of climbing capacity and mortality via upregulating salt expression and inhibiting the dFOXO/SOD pathway. Increased dFOXO/SOD pathway activity played a key role in mediating endurance exercise resistance to the low salt tolerance-induced impairment of climbing capacity and longevity in aging DrosophilaThis article has an associated First Person interview with the first author of the paper.


Assuntos
Ração Animal , Antioxidantes/metabolismo , Drosophila/fisiologia , Longevidade , Condicionamento Físico Animal , Sais , Envelhecimento , Animais , Biomarcadores , Expressão Gênica , Técnicas de Silenciamento de Genes , Atividade Motora , Oxirredução , Sais/administração & dosagem
5.
Huan Jing Ke Xue ; 39(3): 1004-1013, 2018 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965443

RESUMO

The pollution of atmospheric PM2.5 and ambient air quality were investigated in Wuxiang Town, Shanxi Province, China, and the ecological and health risks of the trace heavy metals in PM2.5 were analyzed. The PM2.5 samples were collected every day using a medium-volume PM2.5 sampler in autumn (from Oct. 22 to Nov. 19, 2014) and in winter (from Jan. 12 to Feb. 13, 2015) on the roof of a building at the Wuxiang Environmental Protection Agency (EPA). The mass concentrations of PM2.5 were determined gravimetrically, and the contents of seven trace heavy metals (i. e., As, Cd, Cr, Cu, Ni, Pb, and Zn) in PM2.5 were obtained using Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). The pollution extent, sources, and potential ecological and health risks of the trace heavy metals in PM2.5 were identified and assessed using the geo-accumulation index, ecological risk index, a correlation and principle component analysis, and the exposure risk models of US EPA. Results showed that the average concentration of PM2.5 in winter, approximately three times higher than that in autumn, exceeded the national secondary standard of ambient air quality (GB 3095-2012) on 65% of the sampling days. The heavy metals in PM2.5 mainly originated from anthropogenic activities, with contributions of 58.38% and 18.73% from coal combustion and vehicular emission, respectively. In general, the levels of the heavy metals in PM2.5 followed the order of Cu > Zn > Pb > Cr > As > Ni > Cd, with higher ecological risks from Cd and Cu and higher non-carcinogenic and carcinogenic risks from Cr compared with other metals. It is suggested that greater coal combustion in winter under the adverse geographical conditions for air diffusion in Wuxiang Town were responsible for the increased atmospheric PM2.5 concentration and their ecological and health risks in heavy metals.


Assuntos
Poluentes Atmosféricos/análise , Metais Pesados/análise , Poluição do Ar , China , Monitoramento Ambiental , Material Particulado/análise , Medição de Risco , Estações do Ano
6.
ACS Appl Mater Interfaces ; 7(25): 13996-4003, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26061028

RESUMO

A simple, rapid (10 s) and scalable method to fabricate superhydrophobic polypropylene (PP) fabrics is developed by swelling the fabrics in cyclohexane/heptane mixture at 80 °C. The recrystallization of the swollen macromolecules on the fiber surface contributes to the formation of submicron protuberances, which increase the surface roughness dramatically and result in superhydrophobic behavior. The superhydrophobic PP fabrics possess excellent repellency to blood, urine, milk, coffee, and other common liquids, and show good durability and robustness, such as remarkable resistances to water penetration, abrasion, acidic/alkaline solution, and boiling water. The excellent comprehensive performance of the superhydrophobic PP fabrics indicates their potential applications as oil/water separation materials, protective garments, diaper pads, or other medical and health supplies. This simple, fast and low cost method operating at a relatively low temperature is superior to other reported techniques for fabricating superhydrophobic PP materials as far as large scale manufacturing is considered. Moreover, the proposed method is applicable for preparing superhydrophobic PP films and sheets as well.


Assuntos
Polipropilenos/química , Têxteis , Cicloexanos , Hexanos , Interações Hidrofóbicas e Hidrofílicas , Óleos , Solventes
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