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1.
Huan Jing Ke Xue ; 40(11): 4810-4823, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854546

RESUMO

Northeastern China experiences severe atmospheric pollution, with an increasing occurrence of heavy haze episodes. Based on ground monitoring data, satellite products and meteorological products of atmospheric pollutants in northeast China from 2013 to 2017, the characteristics of spatial and temporal distribution of air quality and the causes of heavy haze events in northeast China were discussed. It was found that the "Shenyang-Changchun-Harbin" city belt was the most polluted area in the region on an annual scale. The spatial distribution of air quality index (AQI) values had a clear seasonality, with the worst pollution occurring in winter, an approximately oval-shaped polluted area around western Jilin Province in spring, and the best air quality occurring in summer and most of autumn. The three periods that typically experienced intense haze events were Period I from late-October to early-November (i. e., late autumn and early winter), Period Ⅱ from late-December to January (i. e., the coldest time in winter), and Period Ⅲ from April to mid-May (i. e., spring). During Period I, strong PM2.5 emissions from seasonal crop residue burning and coal burning for winter heating were the dominant reasons for the occurrence of extreme haze events (AQI>300). Period Ⅱ had frequent heavy haze events (200 < AQI < 300) in the coldest months of January and February(200 < AQI < 300), which were due to high PM2.5 emissions from coal burning and vehicle fuel consumption, a lower atmospheric boundary layer, and stagnant atmospheric conditions. Haze events in Period Ⅲ, with high PM10 concentrations, were primarily caused by the regional transportation of windblown dust from degraded grassland in central Inner Mongolia and bare soil in western Jilin Province. Local agricultural tilling could also release PM10 and enhance the levels of windblown dust from tilled soil.

2.
J Environ Sci (China) ; 54: 101-113, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28391918

RESUMO

This study presents the mass concentrations of PM2.5, O3, SO2 and NOx at one urban, one suburban and two rural locations in the Changchun region from September 25 to October 27 2013. Major chemical components of PM2.5 at the four sites were daily sampled and analyzed. Most of daily concentrations of SO2 (7-82µg/m3), O3 (27-171µg/m3) and NOx (14-213µg/m3) were below the limits of the National Ambient Air Quality Standard (NAAQS) in China. However, PM2.5 concentrations (143-168µg/m3) were 2-fold higher than NAAQS. Higher PM2.5 concentrations (~150µg/m3) were measured during the pre-harvest and harvest at the urban site, while PM2.5 concentrations significantly increased from 250 to 400µgm-3 at suburban and rural sites with widespread biomass burning. At all sites, PM2.5 components were dominated by organic carbon (OC) and followed by soluble component sulfate (SO42-), ammonium (NH4+) and nitrate (NO3-). Compared with rural sites, urban site had a higher mineral contribution and lower potassium (K+ and K) contribution to PM2.5. Severe atmospheric haze events that occurred from October 21 to 23 were attributed to strong source emissions (e.g., biomass burning) and unfavorable air diffusion conditions. Furthermore, coal burning originating from winter heating supply beginning on October 18 increased the atmospheric pollutant emissions. For entire crop harvest period, the Positive Matrix Factorization (PMF) analysis indicated five important emission contributors in the Changchun region, as follows: secondary aerosol (39%), biomass burning (20%), supply heating (18%), soil/road dust (14%) and traffic (9%).


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Poeira/análise , Monitoramento Ambiental , Aerossóis/análise , Agricultura , China , Material Particulado/análise
3.
Infect Dis Poverty ; 5(1): 45, 2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-27251154

RESUMO

BACKGROUND: Tuberculosis (TB) is the notifiable infectious disease with the second highest incidence in the Qinghai province, a province with poor primary health care infrastructure. Understanding the spatial distribution of TB and related environmental factors is necessary for developing effective strategies to control and further eliminate TB. METHODS: Our TB incidence data and meteorological data were extracted from the China Information System of Disease Control and Prevention and statistical yearbooks, respectively. We calculated the global and local Moran's I by using spatial autocorrelation analysis to detect the spatial clustering of TB incidence each year. A spatial panel data model was applied to examine the associations of meteorological factors with TB incidence after adjustment of spatial individual effects and spatial autocorrelation. RESULTS: The Local Moran's I method detected 11 counties with a significantly high-high spatial clustering (average annual incidence: 294/100 000) and 17 counties with a significantly low-low spatial clustering (average annual incidence: 68/100 000) of TB annual incidence within the examined five-year period; the global Moran's I values ranged from 0.40 to 0.58 (all P-values < 0.05). The TB incidence was positively associated with the temperature, precipitation, and wind speed (all P-values < 0.05), which were confirmed by the spatial panel data model. Each 10 °C, 2 cm, and 1 m/s increase in temperature, precipitation, and wind speed associated with 9 % and 3 % decrements and a 7 % increment in the TB incidence, respectively. CONCLUSIONS: High TB incidence areas were mainly concentrated in south-western Qinghai, while low TB incidence areas clustered in eastern and north-western Qinghai. Areas with low temperature and precipitation and with strong wind speeds tended to have higher TB incidences.


Assuntos
Clima , Tuberculose/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Análise Espacial , Tuberculose/microbiologia , Tempo (Meteorologia) , Adulto Jovem
4.
Zhong Yao Cai ; 36(3): 349-53, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24010311

RESUMO

OBJECTIVE: To optimize the extraction conditions of polysaccharide from Moerella iridescens with the microwave-assisted extraction technology by Response surface methodology (RSM). METHODS: Extracting temperature, extracting time and the solvent/solid ratio were selected as factors. The yield of polysaccharide was used as the responsive value. Based on the single factors experiments, a three-factor-three-level experiments design was developed by Box-Benhken central composite design method. The response surface method was employed to analyze the results of experiments. RESULTS: The optimum extraction conditions of polysaccharide were as follows: extracting temperature was 45 degrees C, extracting time was 2.7 h and solvent/solid ratio was 50:1. The predictive maximum yield of polysaccharide was 1.17%. The average yield of polysaccharide in 3 validation experiments was 1.19% and the relative error was 1.70%. CONCLUSION: RSM analysis optimizing the extraction conditions for polysaccharide from Moerella iridescens is feasible, which can improve the extraction rate of Moerella iridescens polysaccharide.


Assuntos
Bivalves/química , Micro-Ondas , Polissacarídeos/isolamento & purificação , Animais , Modelos Estatísticos , Temperatura Ambiente , Fatores de Tempo , Água/química
5.
Curr Microbiol ; 66(5): 499-506, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23325032

RESUMO

Microbial fermentation is a promising technology for hydrogen (H(2)) production. H(2) producers in marine geothermal environments are thermophilic and halotolerant. However, no one has surveyed an environment specifically for thermophilic bacteria that produce H(2) through Fe-Fe hydrogenases (H(2)ase). Using heterotrophic medium, several microflora from a seaweed bed associated with marine hot springs were enriched and analyzed for H(2) production. A H(2)-producing microflora was obtained from Sargassum sp., 16S rRNA genes and Fe-Fe H(2)ase diversities of this enrichment were also analyzed. Based on 16S rRNA genes analysis, 10 phylotypes were found in the H(2)-producing microflora showing 90.0-99.5 % identities to known species, and belonged to Clostridia, Gammaproteobacteria, and Bacillales. Clostridia were the most abundant group, and three Clostridia phylotypes were most related to known H(2) producers such as Anaerovorax odorimutans (94.0 % identity), Clostridium papyrosolvens (98.4 % identity), and Clostridium tepidiprofundi (93.1 % identity). For Fe-Fe H(2)ases, seven phylotypes were obtained, showing 63-97 % identities to known Fe-Fe H(2)ases, and fell into four distinct clusters. Phylotypes HW55-3 and HM55-1 belonged to thermophilic and salt-tolerant H(2)-producing Clostridia, Halothermothrix orenii-like Fe-Fe H(2)ases (80 % identity), and cellulolytic H(2)-producing Clostridia, C. papyrosolvens-like Fe-Fe H(2)ases (97 % identity), respectively. The results of both 16S rRNA genes and Fe-Fe H(2)ases surveys suggested that the thermophilic and halotolerant H(2)-producing microflora in seaweed bed of hot spring area represented previously unknown H(2) producers, and have potential application for H(2) production.


Assuntos
Fontes Termais/microbiologia , Hidrogênio/metabolismo , Hidrogenase/metabolismo , Proteínas com Ferro-Enxofre/metabolismo , Alga Marinha/metabolismo , Alga Marinha/microbiologia , Bacillales/classificação , Bacillales/genética , Clostridium/classificação , Clostridium/genética , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Hidrogenase/genética , Indonésia , Proteínas com Ferro-Enxofre/genética , Metagenoma , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
6.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 41(5): 569-75, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23086652

RESUMO

OBJECTIVE: To optimize extraction and purification methods of acidic polysaccharide from Moerella iridescens (MIAP). METHODS: With alkali extraction process and orthogonal experiment,the time consumption,temperature,pH value of the solution and alcohol concentration during the extraction were optimized. The crude products were deprived of protein,pigment and ion,then were purified with DEAE-cellulose ion-exchange chromatography and verified with Sephadex G-100 and cellulose acetate membrane electrophoresis,and examined with infrared spectrum. RESULTS: The optimized extraction conditions were as follows: extraction time 6 h,extraction temperature 70 degree,the solution pH 8.0 and the concentration of alcohol precipitation 70%. Intuitive features showed that the MIAP was pure white crystalline granular with slight dark brown color. The purification results demonstrated that the target MIAP was eluted and identified as a homogeneous components by DEAE-cellulose ion exchange column,Sephadex G-100 and cellulose acetate membrane electrophoresis. Infrared spectral scanning suggested that MIAP was α-D-type terminated glucopyranose. Intuitive features showed that MIAP was soft and cottony white. CONCLUSION: The extraction process with orthogonal test has been optimized and the acidic polysaccharide from Moerella iridescens is successfully isolated.


Assuntos
Bivalves/química , Cromatografia DEAE-Celulose/métodos , Polissacarídeos/isolamento & purificação , Animais
7.
Ying Yong Sheng Tai Xue Bao ; 23(10): 2812-20, 2012 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-23359944

RESUMO

Taking Zhengzhou City, the capital of Henan Province in Central China, as the study area, and by using the theories and methodologies of diversity, a discreteness evaluation on the regional surface water, normalized difference vegetation index (NDVI), and land surface temperature (LST) distribution was conducted in a 2 km x 2 km grid scale. Both the NDVI and the LST were divided into 4 levels, their spatial distribution diversity indices were calculated, and their connections were explored. The results showed that it was of operability and practical significance to use the theories and methodologies of diversity in the discreteness evaluation of the spatial distribution of regional thermal environment. There was a higher overlap of location between the distributions of surface water and the lowest temperature region, and the high vegetation coverage was often accompanied by low land surface temperature. In 1988-2009, the discreteness of the surface water distribution in the City had an obvious decreasing trend. The discreteness of the surface water distribution had a close correlation with the discreteness of the temperature region distribution, while the discreteness of the NDVI classification distribution had a more complicated correlation with the discreteness of the temperature region distribution. Therefore, more environmental factors were needed to be included for a better evaluation.


Assuntos
Biodiversidade , Ecossistema , Plantas/classificação , Solo/química , Água/análise , China , Meio Ambiente , Monitoramento Ambiental/métodos , Desenvolvimento Vegetal , Temperatura Ambiente
8.
Ying Yong Sheng Tai Xue Bao ; 22(1): 121-8, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21548298

RESUMO

A GIS-based 500 m x 500 m soil sampling point arrangement was set on 248 points at Wenshu Town of Yuzhou County in central Henan Province, where the typical Ustic Cambosols locates. By using soil digital data, the spatial database was established, from which, all the needed latitude and longitude data of the sampling points were produced for the field GPS guide. Soil samples (0-20 cm) were collected from 202 points, of which, bulk density measurement were conducted for randomly selected 34 points, and the ten soil property items used as the factors for soil quality assessment, including organic matter, available K, available P, pH, total N, total P, soil texture, cation exchange capacity (CEC), slowly available K, and bulk density, were analyzed for the other points. The soil property items were checked by statistic tools, and then, classified with standard criteria at home and abroad. The factor weight was given by analytic hierarchy process (AHP) method, and the spatial variation of the major 10 soil properties as well as the soil quality classes and their occupied areas were worked out by Kriging interpolation maps. The results showed that the arable Ustic Cambosols in study area was of good quality soil, over 95% of which ranked in good and medium classes and only less than 5% were in poor class.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Ecossistema , Solo/análise , China , Estudos de Avaliação como Assunto , Sistemas de Informação Geográfica , Controle de Qualidade
9.
Ying Yong Sheng Tai Xue Bao ; 22(1): 129-36, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21548299

RESUMO

Taking the mid and low yielding fields in Yanjin County, Henan Province as a case, and selecting soil organic matter, total N, total P, total K, available N, available P, available K, pH value, and cation exchange capacity as indicators, a comprehensive evaluation on soil fertility was conducted by the method of fuzzy mathematics and using software ArcGIS 9.2. Based on this evaluation, the differences in the soil fertility level under different soil profile configuration pattern were analyzed. In the study region, soils were slightly alkaline, poorer in total N, total P, available N, cation exchange capacity, organic matter, and available K, and medium in available P and total K. The integrated fertility index was 0.14-0.63, indicating that the soil fertility in the region was on the whole at a lower level. There existed significant differences in all indicators except available P and total K under different soil profile configuration patterns (P < 0.05), suggesting the close relationship between soil fertility and soil profile configuration. The soil profile loamy in surface soil and clayey in subsurface soil had a higher level of soil fertility, followed by that loamy in surface soil and sandy in subsurface soil, and sandy in both surface and surface soil. Overall, the soils in the region were bad in profile configuration, poor in water and nutrient conservation, and needed to be ameliorated aiming at these features.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Ecossistema , Sistemas de Informação Geográfica , Solo/análise , China , Estudos de Avaliação como Assunto , Lógica Fuzzy , Modelos Teóricos , Nitrogênio/análise , Fósforo/análise , Controle de Qualidade
10.
Ying Yong Sheng Tai Xue Bao ; 22(1): 165-70, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21548304

RESUMO

By using two Landsat remote sensing images (May 14, 1988 by TM sensor and May 10, 2001 by ETM+ sensor) and local meteorological data, this paper analyzed the causes and harms of urban heat island (UHI) in Zhengzhou City. The brightness temperatures of the images were calculated by mono-window algorithm, and related thematic maps were figured out. The results showed that with the expanding urban area of Zhengzhou City, the UHI effect was growing. Comparing with that in 1988, the high-temperature region of the City in 2001 had a clear shift and expansion towards northeast and southwest, being similar to the change trends of the low vegetation coverage area and urban land area. In order to alleviate the growing UHI effect, attentions should be paid on the urban greening work and the choice of reasonable greening patterns in the process of urbanization.


Assuntos
Planejamento de Cidades , Ecossistema , Monitoramento Ambiental/métodos , Temperatura Alta , China , Cidades , Aquecimento Global/estatística & dados numéricos , Comunicações Via Satélite
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