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1.
Huan Jing Ke Xue ; 44(10): 5392-5399, 2023 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-37827757

RESUMO

In recent years, the situation of ozone pollution in China has become increasingly severe, with PM2.5 being the main pollutant in the atmospheric environment of several cities. Meteorological conditions, particularly temperature and humidity, have a great influence on ozone formation. Therefore, understanding and quantifying the impact of the variation in temperature and humidity on ozone level can effectively provide the theoretical basis for the government to prevent and control ozone pollution. By analyzing the relationship among the daily maximum temperature (Tmax), relative humidity (RH), and the maximum 8-h running average ozone (O3-8h) measured from January 1, 2015 to July 31, 2022, a linear positive correlation between O3-8h and Tmax was observed in the seven regions with serious ozone pollution, and the temperature penalty factor ranged from 2.1-6.0 µg·(m3·â„ƒ)-1; a nonlinear correlation between O3-8h and RH was also observed, and O3-8h was the highest when RH was 55%. The sensitivity of different regions to Tmax and RH was slightly different; generally, the most suitable meteorological conditions for ozone formation were 29℃ ≤ Tmax< 38℃ and 40% ≤ RH<70%. In the Yangtze River Delta, Jiangsu-Anhui-Shandong-Henan, and the middle reaches of the Yangtze River, under extreme high temperature conditions (Tmax ≥ 35℃), O3-8h stopped increasing with the increase in temperature and even dropped; simultaneously, it was often accompanied with a small increase in particulate matter. It may be related to the heterogeneous reaction of some precursors with higher water vapor content and the increase in ozone heterogeneous sink.

2.
Chem Commun (Camb) ; 58(66): 9262-9265, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35903977

RESUMO

A ratiometric fluorescent and colorimetric dual-modal sensing strategy is reported to distinguish and detect D2O from H2O based on ground-state proton transfer for the first time. It enables synchronous dual-modal changes towards different fractions of D2O and facilitates naked-eye recognition. The probe can provide a more accurate monitoring protocol for D2O analysis.


Assuntos
Colorimetria , Corantes Fluorescentes , Colorimetria/métodos , Prótons , Espectrometria de Fluorescência/métodos
3.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 36(4): 405-409, 2022 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-35426277

RESUMO

Objective: To investigate the application and effectiveness of metatarsal mortise and tenon shortening osteotomy in the treatment of macrodactyly in children. Methods: The clinical data of 17 children with macrodactyly (18 feet and 27 toes) admitted between January 2018 and January 2020 were retrospectively analyzed. There were 12 males (12 feet and 18 toes) and 5 females (6 feet and 9 toes); the age ranged from 1 to 13 years, with a median age of 5 years. All children were treated with metatarsal mortise and tenon shortening osteotomy. Ten cases of single-segment metatarsals were shortened, 7 cases of 2-segment metatarsals, and 1 case of 3-segment metatarsals; involved 1 foot of single toe, 9 feet of 2 toes, 3 feet of 3 toes, 3 feet of 4 toes, and 2 feet of 5 toes. Five cases had lameness, and 1 case had limited walking with the big toes of both feet, and there was no obvious pain in all children. X-ray films showed that the involved phalanges were thickened and increased in 18 feet, and the deformity of the distal segment was heavier than that of the proximal segment in 13 feet, and the two were similar in 5 feet. The length of metatarsal shortening was 0.7-2.5 cm, with an average of 1.2 cm. The clinical healing of shortened metatarsal fractures in children was observed after operation, and the occurrence of related complications was recorded. Results: All 17 children were followed up 6-22 months, with an average of 14 months. All incisions healed by first intention. The osteotomy ends of 27 toes were clinically healed after operation, and the healing time was 4-8 weeks. No nonunion, fracture displacement, malunion, epiphyseal plate premature closure, and needle tract infection occurred. Conclusion: Metatarsal mortise and tenon shortening osteotomy is a good osteotomy method. It can improve the stability of the osteotomy end and increase the contact surface of the osteotomy end, which is conducive to the healing of the osteotomy end and is suitable for the treatment of macrodactyly.


Assuntos
Fraturas Ósseas , Hallux Valgus , Ossos do Metatarso , Adolescente , Criança , Pré-Escolar , Feminino , Dedos/anormalidades , Hallux Valgus/cirurgia , Humanos , Lactente , Deformidades Congênitas dos Membros , Masculino , Ossos do Metatarso/cirurgia , Metatarso , Osteotomia/métodos , Estudos Retrospectivos , Resultado do Tratamento
4.
Pharmgenomics Pers Med ; 15: 55-64, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35125881

RESUMO

OBJECTIVE: This study aimed to explore the pathogenic genes and mutation sites of macrodactyly. METHODS: Whole-exome sequencing was performed on the pathological tissue and peripheral blood of 12 patients with macrodactyly who were operated in our hospital between June 2018 and May 2020. In order to conduct comprehensive bioinformatics analysis and screen the pathogenic genes of macrodactyly, the patients were divided into four groups: macrodactyly of finger group, macrodactyly of foot group, macrodactyly and syndactyly of finger group, and macrodactyly and syndactyly of foot group. The results of the whole-exome sequencing were verified using Sanger sequencing in order to clarify the pathogenic genes and mutation sites of macrodactyly, and immunohistochemical analysis of the protein signaling pathways encoded by the pathogenic genes was performed to observe the protein expression and further verify the mutant genes. RESULTS: In the comprehensive bioinformatics analysis and Sanger verification of the whole-exome sequencing, the PIK3CA gene mutation was screened as the pathogenic gene of macrodactyly. The mutation sites were identified as the p.E542K (c.G1624A) and p.E545K (c.G1633A) sites of exon10 and the p.H1047R (c.A3140G) and p.G1049R (c.G3145C) sites of exon21. Among these, the p.G1049R (c.G3145C) locus was found in macrodactyly for the first time. The mutation of the PIK3CA gene was also found to lead to increased expression of serine-threonine kinase (AKT) in adipocytes in the PI3K-AKT-mTOR signaling pathway. CONCLUSION: Mutation of the PIK3CA gene leads to the enhancement of the PI3K-AKT-mTOR signaling pathway, which is the cause of macrodactyly. There is also some diversity in PIK3CA gene mutation sites.

5.
Sci Total Environ ; 821: 153541, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35101481

RESUMO

Under weak weather systems, pollutants circulate on plains and hillsides by means of oscillatory mountain-plain breezes (MPB). To investigate the impact of MPB on ambient volatile organic compounds (VOCs) on the northern edge of the North China Plain (NCP) region, synchronous online VOCs observations were first performed in the southwestern (Beijing, urban area) and northeastern (Xinglong, background area) of the dominant wind directions from September 11, 2020, to October 13, 2020. The results revealed that during the observation period, the average mixing ratios of TVOCs in Beijing and Xinglong were 32.5 ± 21.6 and 14.2 ± 8.6 ppbv, respectively, and a coincident temporal evolution trend of VOCs was observed at the two sites. Combined with the results of the backward trajectory, southerly air transport led to a significant increase in VOCs concentration, and southerly airflow was usually accompanied by apparent MPB circulation. Furthermore, the occurrence of MPB led to a sharp increase (1.5 times) in VOCs concentration in both Beijing and Xinglong. This study indicates that the periodic oscillation of the MPB leads to the large-scale pollution of "garbage out and garbage in", and the VOCs discharged by industry are the key to future control.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental/métodos , Ozônio/análise , Compostos Orgânicos Voláteis/análise , Vento
6.
Sci Total Environ ; 806(Pt 4): 150950, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34656595

RESUMO

The vertical distribution of carbonaceous aerosol impacts climate change, air quality and human health, but there is a lack of in-situ vertical observations of black (BC) and brown carbon (BrC). Thus, the characteristic of vertical profiles of BC concentration, particle number concentration (PNC), O3 concentration and optical absorption of BC and BrC were observed in a suburban site over North China Plain, where heavy pollution of PM2.5 and O3 always occurred in winter and summer, respectively. In winter, during a heavy pollution episode, the BC and PNC was near uniformly distributed within mixing layer (ML) (15.2 ± 6.7 µg m-3 and 678 ± 227 p cm-3, respectively) and decreased with altitude above the ML. The BC heating rate reached about 0.13 K h-1 during the heaviest pollution day. In summer, the BC concentration (2.9 ± 1.3 µg m-3) in ML during the middle O3 pollution events was higher than that (1.7 ± 0.6 µg m-3) during the light O3 pollution. The light absorption coefficients of BC at 880 nm and BrC at 375 nm measured in the early morning were lower than that in the daytime, and the contribution of BrC to total light absorption of carbonaceous aerosols was in the range of 27-47%. In addition, BC was effectively transported to high altitude than BrC in the daytime. The light absorption of secondary BrC in the daytime was higher 10-20% than that in the early morning. Simultaneously, the contribution of secondary BrC to the total BrC light absorption at 375 nm was range from 32% to 68% within 1000 m.


Assuntos
Poluentes Atmosféricos , Carbono , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , China , Monitoramento Ambiental , Humanos , Material Particulado/análise
7.
Sci Total Environ ; 791: 148226, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34412400

RESUMO

Absorbing carbonaceous aerosols, i.e. black and brown carbon (BC and BrC), affected heavily on climate change, regional air quality and human health. The nationwide lockdown measures in 2020 were performed to against the COVID-19 outbreak, which could provide an important opportunity to understand their variations on light absorption, concentrations, sources and formation mechanism of carbonaceous aerosols. The BC concentration in Wuhan megacity (WH) was 1.9 µg m-3 during lockdown, which was 24% lower than those in the medium-sized cities and 26% higher than those in small city; in addition, 39% and 16-23% reductions occurred compared with the same periods in 2019 in WH and other cities, respectively. Fossil fuels from vehicles and industries were the major contributors to BC; and compared with other periods, minimum contribution (64-86%) mainly from fossil fuel to BC occurred during the lockdown in all cities. Secondary BrC (BrCsec) played a major role in the BrC light absorption, accounting for 65-77% in WH during different periods. BrCsec was promoted under high humidity, and decreased through the photobleaching of chromophores under higher Ox. Generally, the lockdown measures reduced the BC concentrations significantly; however, the variation of BrCsec was slight.


Assuntos
COVID-19 , Fuligem/análise , Carbono/análise , China , Cidades , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , SARS-CoV-2
8.
J Environ Sci (China) ; 92: 187-199, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32430122

RESUMO

An intensive and persistent regional ozone pollution event occurred over eastern China from 25 June to 5 July 2017. 73 out of 96 selected cities, most located in the Beijing-Tianjin-Hebei and the surrounding area (BTHS), suffered severe ozone pollution. A north-south contrast ozone distribution, with higher ozone (199 ± 33 µg/m3) in the BTHS and lower ozone (118 ± 25 µg/m3) in the Yangtze River Delta (YRD), was found to be dominated by the position of the West Pacific Subtropical High (WPSH) and mid-high latitude wave activities. In the BTHS, the positive anomalies of geopotential height at 500 hPa and temperature at the surface indicated favorable meteorological conditions for local ozone formation. Prevailing northwesterly winds in the mid-high troposphere and warm advection induced by weak southerly winds in the low troposphere resulted in low-moderate relative humidity (RH), less total cloud cover (TCC), strong solar radiation and high temperatures. Moreover, southerly winds prevailing over the BTHS aggravated the pollution due to regional transportation of O3 and its precursors. On one hand, the deep sinking motion and inversion layer suppressed the dispersion of pollutants. On the other hand, O3-rich air in the upper layer was maintained at night due to temperature inversion, which facilitated O3 vertical transport to the surface in the next-day morning due to elevated convection. Generally, temperature, UV radiation, and RH showed good correlations with O3 in the BTHS, with rates of 8.51 (µg/m3)/°C (within the temperature range of 20-38°C), 59.54 (µg/m3)/(MJ/m2) and -1.93 (µg/m3)/%, respectively.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Ozônio/análise , Pequim , China , Cidades , Monitoramento Ambiental , Estações do Ano
9.
Sci Total Environ ; 710: 136304, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31927286

RESUMO

Crop residue burning in China increased significantly in the last decade, especially it took up a majority in Northeast China, which plays an important role of severe haze pollution. Hence, two main types of crop residues (corn and rice straw) were chosen to characterize the particle number concentration, chemical components of fine particulate matter and optical properties of carbonaceous aerosols by a suite of fast-response online portable instruments, together with offline sampling and analysis, during the field-based combustion experiments in Northeast China. For the range of 250 and 2500 nm, more particles were emitted from rice straw burning than those from corn straw burning, and the time-averaged number concentration of particles during the flaming process was approximately 2 times higher than that during the smoldering process for these two straws. Organic carbon (OC), elemental carbon (EC) and water-soluble ions were the most abundant components and accounted for 42.5 ± 7.5%, 7.7 ± 1.7% and 18.0 ± 3.4% of the PM2.5, respectively. Furthermore, rice straw burning emitted higher OC and lower Cl- and K+ than those from corn straw burning. The average absorption Ångström exponent (AAE) of carbonaceous aerosols was 2.1 ± 0.3, while the AAE of brown carbon (BrC) was 4.7 ± 0.4 during the whole burning process. On average, BrC contributed to 63% and 20% of the total light absorption at 375 nm and 625 nm, respectively. Parameterization of BrC absorption revealed that the fraction of absorption from BrC has a reasonably good correlation with EC/OC (-0.84) and AAE (0.94) at 375 nm. Generally, combustion conditions can affect the optical properties of carbonaceous aerosols, and a negative correlation (-0.77) was observed between the AAE and modified combustion efficiency; in addition, the percentage of absorption due to BrC were lower at the flaming phase.

10.
Environ Int ; 134: 105283, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31743806

RESUMO

In the last decade, North China (NC) has been one of the most populated and polluted regions in the world. The regional air pollution has had a serious impact on people's health; thus, all levels of government have implemented various pollution prevention measures since 2013. Based on multi-city in situ environmental and meteorological data, as well as the meteorological reanalysis dataset from 2013 to 2017, regional pollution characteristics and meteorological formation mechanisms were analyzed to provide a more comprehensive understanding of the evolution of PM2.5 in NC. The domain-averaged PM2.5 was 79 ±â€¯17 µg m-3 from 2013 to 2017, with a decreasing rate of 10 µg m-3 yr-1. Two automatic computer algorithms were established to identify 6 daily regional pollution types (DRPTs) and 48 persistent regional pollution events (PRPEs) over NC during 2014-2017. The average PM2.5 concentration for the Large-Region-Pollution type (including the Large-Moderate-Region-Pollution and Large-Severe-Region-Pollution types) was 113 ±â€¯40 µg m-3, and more than half of Large-Region-Pollution days and PRPEs occurred in winter. The PRPEs in NC mainly developed from the area south of Hebei. The number of Large-Region-Pollution days decreased notably from 2014 to 2017, the annual number of days varying between 194 and 97 days, whereas a slight decline was observed in winter. In addition, the averaged PM2.5 concentrations and the numbers and durations of the PRPEs decreased. Lamb-Jenkinson weather typing was used to reveal the impact of synoptic circulations on PM2.5 across NC. Generally, the contributions of the variations in circulation to the reduction in PM2.5 levels over NC between 2013 and 2017 were 64% and 45% in summer and winter, respectively. The three most highly polluted weather types were types C, S and E, with an average PM2.5 concentration of 137 ±â€¯40 µg m-3 in winter. Furthermore, three typical circulation dynamics were categorized in the peak stage of the PRPEs, namely, the southerly airflow pattern, the northerly airflow pattern and anticyclone pattern; the averaged relative humidity, recirculation index, wind speed and boundary layer height were 63%, 0.33, 2.0 m s-1 and 493 m, respectively. Our results imply that additional emission reduction measures should be implemented under unfavorable meteorological situations to attain ambient air quality standards in the future.


Assuntos
Poluição do Ar , Poluentes Atmosféricos , China , Cidades , Monitoramento Ambiental , Material Particulado , Estações do Ano
11.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(5): 586-589, 2019 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-31090352

RESUMO

OBJECTIVE: To investigate the effectiveness of radial-lateral forearm free perforator flap on repairing of soft tissue defects in the finger. METHODS: Between January 2017 and May 2018, 26 cases of finger skin defects were treated with radial-lateral forearm free perforator flap based on the radial branch of the posterior interosseus artery. There were 21 males and 5 females, with an average age of 26.6 years (range, 19-56 years). The cause of injury included the cutting injury in 16 cases and crush injury in 10 cases. The interval between injury and admission was 30 minutes to 4 hours (mean, 1.5 hours). The injury located at thumb in 6 cases, index finger in 8 cases, middle finger in 6 cases, ring finger in 3 cases, and little finger in 3 cases; and at the dorsum of finger in 6 cases, the lateral side in 6 cases, and the palm in 14 cases. All wounds were accompanied with the tendon and bone exposures, and phalangeal fractures occurred in 10 cases. The size of the defects ranged from 2.0 cm×1.0 cm to 4.0 cm×2.5 cm. And the size of the flap ranged from 2.5 cm×1.5 cm to 4.5 cm×3.0 cm. All wounds at donor sites were sutured directly. RESULTS: All the 26 cases were followed up 4-12 months (mean, 7 months). The 24 flaps survived uneventfully after operation, and the wounds healed by first intention. Partial necrosis occurred at the distal part in 2 flaps, and secondary healing achieved after debridement and dressing. All incisions at donor sites healed by first intention. The appearance and texture of all flaps were satisfactory. The two-point discrimination of the flaps was 5-10 mm (mean, 8 mm) at 4 months after operation. Sensory of the flaps was grade S 3. Only linear scar was noted at the donor site. CONCLUSION: The radial-lateral forearm free perforator flap in repairing of the soft tissues in finger can shorten the disease duration, reduce the damage of the donor site, and improve the patients' quality of life.


Assuntos
Traumatismos dos Dedos , Retalho Perfurante , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Transplante de Pele , Resultado do Tratamento , Adulto Jovem
12.
Huan Jing Ke Xue ; 40(4): 1697-1704, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087910

RESUMO

Support vector machine regression (SVMr) was proposed to forecast hourly ozone (O3) concentrations, daily maximum O3 concentrations, and maximum 8 h moving average O3 concentrations (O3 8 h) by employing the observations of meteorological variables and O3 and its precursors during the high O3 periods from May 20 to August 15, 2016 at an industrial area in Nanjing. The squared correlation coefficient (R2) of the hourly O3 concentrations forecast was 0.84. The mean absolute error (MAE) and mean absolute percentage error (MAPE) were 3.44×10-9 and 24.48, respectively. The key factors for the hourly O3 forecast were the O3 pre-concentrations, amount of ultraviolet radiation B (UVB), and the NO2 concentration. The main factors for the O3 daily maximum forecast were the NOx concentrations at 07:00 and the UVB level. Temperature and UVB played an important role in predicting O3 8 h. In general, taking precursors into account could increase the accuracy of O3 prediction by 10%-28%. For O3 concentration forecasting, SVMr gave significantly better predictions than multiple linear regression methods.

13.
Huan Jing Ke Xue ; 39(2): 502-510, 2018 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964809

RESUMO

Ambient volatile organic compounds (VOCs) were continuously measured during the high ozone (O3) periods from May 1 to May 31 and June 1 to July 16, 2015 at an industrial area in the north suburb of Nanjing. A positive matrix factorization (PMF) model and an observation-based model (OBM) were combined for the first time to investigate the contributions of VOC sources and species to local photochemical O3 formation. The average VOC concentrations in 2014 and 2015 were (36.47±33.44)×10-9 and (34.69±34.08)×10-9, respectively. The VOC sources identified by the PMF model for 2014 and 2015 belonged to 7 source categories, including vehicular emissions, liquefied petroleum gas usage, biogenic emissions, furniture manufacturing industry, chemical industry, chemical coating industry, and chemical materials industry emission sources. The OBM was modified to assess the O3 precursors' relationships. Generally, photochemical O3 production was VOC limited, with positive relative incremental reactivity (RIR) values for VOC species and a negative RIR value for NO. It can be seen that alkenes (1.20-1.79) and aromatics (1.42-1.48) presented higher RIR values and controlling O3 would be the most effective when the VOC emissions from alkenes were reduced by 80%. Vehicle emissions (1.01-1.11), LPG (0.74-0.82), biogenic emissions (0.34-0.42), and furniture manufacturing industry (0.32-0.49) sources were the top four VOC sources making significant contributions to photochemical O3 formation, which suggests that controlling vehicle emissions, biogenic emissions, LPG, and furniture manufacturing industry sources should be the most effective strategy to reduce photochemical O3 formation.

14.
Huan Jing Ke Xue ; 38(2): 453-460, 2017 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964499

RESUMO

BTEX concentrations were determined by GC5000 online gas chromatography in the atmosphere of the north suburb of Nanjing in March 2013 to February 2014, using the EPA human exposure analysis evaluation method for benzene series compounds of volatile organic compounds (VOCs) in health risk assessment. The results showed that the total amount of BTEX showed the variation characteristics of spring > winter > autumn > summer. BTEX concentration was higher in the periods of 07:00-10:00 and 17:00-20:00, and the lowest was detected between 13:00-15:00; At the weekend, the concentration of BTEX was higher than on the working day. The sources of BTEX included traffic sources, industrial sources and solvent evaporation. The HQ of BTEX in all four seasons showed the order of benzene > xylene > ethylbenzene > toluene, and the HQ risk values were within the safety range in all analysis periods. The distribution of R value was winter > autumn > spring > summer, and R was higher than the safety threshold for all the analyses, indicating the existence of carcinogenic risk.


Assuntos
Poluentes Atmosféricos/análise , Derivados de Benzeno/análise , Monitoramento Ambiental , Compostos Orgânicos Voláteis/análise , Atmosfera , Benzeno , China , Cidades , Humanos , Medição de Risco , Tolueno , Xilenos
15.
Huan Jing Ke Xue ; 38(1): 1-12, 2017 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965025

RESUMO

Volatile organic compounds (VOCs) in the atmosphere of the north suburb of Nanjing in December 2015 were determined by GC5000 online gas chromatography,and the main composition and characteristics of VOCs were analyzed by using the PMF receptor model sources of VOCs parsing.The United States Environmental Protection Agency (EPA) human exposure analysis and evaluation method in the United States were used to evaluate Human health risk of benzene series.The results showed that there were 6 sources in the PMF mode.Natural gas leakage accounted for 32.05%,automobile exhaust accounted for 18.99%,solvent use 13.67%,industrial emissions 2 13.20%,gasoline volatile 11.72%,and industrial emissions 1(chemical type)10.36%.The high value areas of the emission source were in accordance with the location of pollution sources surrounding the observation point.The B/T ratio was 0.74,which was at a relatively high level.The noncarcinogenic risk hazard quotient value HQ at 06:00 reached the highest value.HQ risk values were within the safe range specified by EPA.HQ of each source was as follows:automobile exhaust emissions 20.67×10-2,solvent use 6.97×10-2,natural gas leakage 6.34×10-2.In the carcinogenic risk of benzene,automobile exhaust emissions was 4.11×10-6,and natural gas leakage was 1.09×10-6,both were higher than the EPA specified safety threshold.


Assuntos
Poluentes Atmosféricos/análise , Benzeno/análise , Monitoramento Ambiental , Compostos Orgânicos Voláteis/análise , China , Humanos , Medição de Risco , Emissões de Veículos
16.
Huan Jing Ke Xue ; 38(5): 1733-1742, 2017 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965075

RESUMO

Volatile organic compounds (VOCs) were determined by GC5000, an automatic on-line Gas Chromatography-Flame Ionization Detector. Elemental carbon (EC) and organic carbon (OC) were determined by the thermal/optical method using DRI-2001A during the periods of June 15th-July 15th 2015 and December 16th 2015-January 15th 2016. The concentration of secondary organic aerosol(SOA) was estimated by fractional aerosol coefficients (FAC) and EC tracer method. The source apportionment relied on the positive matrix factorization model (PMF). There were several conclusions:First, aromatic hydrocarbon was the main substance causing the SOA pollution in the Nanjing Industrial district, the contributions of aromatic hydrocarbon to SOA during summer and winter were 80.39% and 94.63%, respectively. The main contributers were benzene, toluene, ethylbenzene, m,p-xylene and o-xylene (BTEX). In the summer, SOA concentration ranged from 5.84-20.88 µg·m-3 with an average of 12.15 µg·m-3 and in the winter ranged from 2.17-17.73 µg·m-3 in which the average concentration was 6.91 µg·m-3. Secondly, SOA concentration decreased when wind and precipitation increased. By using the PMF model, a total of 7sources of SOA were determined in summer and 6 were determined in winter. There were 3 main sources in summer, including painting, petroleum processing and petrochemical industry, and the contributions to SOA were 0.65 µg·m-3, 0.21 µg·m-3, 0.18 µg·m-3, respectively. In winter, the most important SOA pollution was from painting, in which the contribution was 0.94 µg·m-3.

17.
Artigo em Chinês | MEDLINE | ID: mdl-24063179

RESUMO

OBJECTIVE: To study the anatomical basis of micro transverse flap pedicled with the superfical palmar branch of radial artery from the palmar wrist for using this free flap to repair soft tissue defect of the finger. METHODS: Thirty-eight fresh upper limb specimens (22 males and 16 females; aged 26-72 years with an average of 36 years; at left and right sides in 19 limbs respectively) were dissected and observed under operating microscope. Two specimens were made into casting mould of artery with bones, and 2 specimens were injected with red emulsion in radial artery. Thirty-four specimens were injected with 1% gentian violet solution in the superfical palmar branch of the radial artery. A transverse oval flap in the palmar wrist was designed, the axis of the flap was the distal palmar crease. The origin, distribution, and anastomosis of the superfical palmar branch of the radial artery were observed. RESULTS: The superficial palmar branch of the radial artery was constantly existed, it usually arises from the main trunk of the radial artery, 1.09-3.60 cm to proximal styloid process of radius. There were about 2-5 branches between the origin and the tubercle of scaphoid bone. The origin diameter was 1.00-3.00 mm, and the distal diameter at the styloid process of radius was 1.00-2.90 mm. The venous return of flap passed through 2 routes, and the innervations of the flap mainly from the palmar cutaneous branch of the median nerve. The area of the flap was 4 cm x 2 cm-6 cm x 2 cm. CONCLUSION: The origin and courses of the superficial palmar branch of the radial artery is constant, and its diameter is similar to that of the digital artery. A transverse oval flap pedicled with the superfical palmar branch of radial artery in the palmar wrist can be designed to repair defects of the finger.


Assuntos
Traumatismos dos Dedos/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Artéria Radial/anatomia & histologia , Retalhos Cirúrgicos/irrigação sanguínea , Punho , Adulto , Idoso , Cadáver , Feminino , Mãos/irrigação sanguínea , Mãos/inervação , Humanos , Masculino , Nervo Mediano/anatomia & histologia , Nervo Mediano/cirurgia , Pessoa de Meia-Idade , Artéria Radial/cirurgia , Pele/irrigação sanguínea , Pele/lesões , Pele/inervação , Transplante de Pele/métodos , Retalhos Cirúrgicos/inervação , Punho/irrigação sanguínea , Punho/inervação
18.
Phys Chem Chem Phys ; 15(41): 18174-8, 2013 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-24068110

RESUMO

The CIGS solar cell is one of the most promising photovoltaic devices due to the achievement of the highest conversion efficiency (>20%) among all thin-film solar cells. The CIGS cell has a glass/Mo/CIGS/CdS/TCO configuration, and the CIGS-Mo interface is a Schottky barrier to holes. During the sulfurization-after-selenization (SAS) CIGS formation process with H2Se gas, the Mo surface transforms naturally into MoSe2 at the CIGS-Mo interface. In this work, the electrical impact of MoSe2 on CIGS solar cells was investigated. Different CIGS-Mo interfaces were prepared with two CIGS processes. One is SAS, and the other is the sequential-sputtering-selenization CIGS process with Se gas. Formation of MoSe2 is hardly observed in the latter process. Samples were characterized by XRD, the van der Pauw method, reflectance, and visual inspection. Besides, Schottky barrier heights of cells were extracted from J-V-T measurements. For the first time, it was experimentally shown that the existence of thin MoSe2 film can decrease the apparent Schottky barrier height of CIGS solar cells. In addition, 1-dimensional numerical simulation showed that a larger barrier height affects both the fill factor and open-circuit voltage. Therefore, the formation of MoSe2 during the CIGS process should minimize the negative effect of Schottky barrier on solar-cell performances, especially with large Schottky barrier.

19.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 27(12): 1475-9, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24640369

RESUMO

OBJECTIVE: To investigate the clinical application of micro transverse flap pedicled with superficial palmar branch of radial artery from palmar wrist to repair skin defect of finger. METHODS: Twenty-six cases (26 fingers) with skin defect of finger were repaired with micro transverse flap pedicled with superficial palmar branch of radial artery from palmar wrist between December 2011 and February 2013. There were 20 males and 6 females with the average age of 31.5 years (range, 20-56 years). The causes of injury included cutting injury in 20 cases and crushing injury in 6 cases. The time from injury to admission was 1-5 hours with an average of 2 hours. Injured fingers included thumb in 6 cases, index finger in 6 cases, middle finger in 6 cases, ring finger in 4 cases, and little finger in 4 cases; the locations were the dorsal side of the finger in 6 cases, lateral side in 6 cases, and the volar of the finger tip in 14 cases; there were 4 cases on the proximal phalangeal skin, 8 cases on the middle phalangeal skin, and 14 cases on the distal phalangeal skin. The defect area ranged from 2.0 cm x 1.5 cm to 4.0 cm x 2.0 cm, and the flap area ranged from 2.5 cm x 2.0 cm to 4.5 cm x 2.5 cm. All the donor sites were directly sutured. RESULTS: The flaps of 25 cases survived well after operation, and wound healed by first intention; 1 case had partial necrosis and the wound had a scar healing by changing dressing. All cases were followed up 6-12 months (mean, 10 months). The color and appearance of the flaps were satisfactory with tender texture. The two-point discrimination of the flap was 5-8 mm (mean, 6.8 mm). The donor sites healed primarily without scar contracture and limitation of wrist flexion or extension. CONCLUSION: The micro transverse flap pedicled with superficial palmar branch of radial artery from palmar wrist is a good option to repair skin defect of finger. It has the advantages of hidden donor site, the same operative field, great comparability of flap and finger skin, and it can be used as a vascularized tendon or nerve graft.


Assuntos
Traumatismos dos Dedos/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Pele/lesões , Retalhos Cirúrgicos , Adulto , Feminino , Dedos/irrigação sanguínea , Dedos/cirurgia , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Radial/cirurgia , Transplante de Pele/métodos , Lesões dos Tecidos Moles/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Tendões/transplante , Resultado do Tratamento , Cicatrização , Punho/cirurgia , Adulto Jovem
20.
Artigo em Chinês | MEDLINE | ID: mdl-18822724

RESUMO

OBJECTIVE: To report the operation method and the clinical effect of decompression and anterior transposition of the ulnar nerve with inferior ulnar collateral artery for cubital tunnel syndrome. METHODS: From September 2005 to May 2006, 25 cases of cubital tunnel syndrome were treated by the method of decompression and anterior transposition of the ulnar nerve with inferior ulnar collateral artery. There were 19 males and 6 females with an average of 60 years (20-72 years). The disease course was 2 months to 3 years (mean 6.7 months). The causes were osteoarthritis in 23 cases, cubital tunnel cyst in 1 case and ulnar nerve olisthy in 1 case. According to Pasque grading system for cubital tunnel syndrome, 19 cases were graded as good and 6 cases were graded as poor. Electrophysiological examination showed the motor nerve conduction velocity of the ulnar nerve around the elbow joint was less than 42 m/s. RESULTS: All wounds healed by first intention and no operative complications and recurrences occurred. All patients were followed up for one year to two and half years (13.9 months on average). According to Pasque grading system for cubital tunnel syndrome, 15 cases were graded as excellent, 9 cases as good and 1 case as fair. The excellent and good rate was 96%, indicating a significant difference compared with the results before operation (P < 0.05). Electrophysiological examination showed the motor nerve conduction velocity of the ulnar nerve around the elbow joint was more than 42 m/s. CONCLUSION: The method of decompression and anterior transposition of the ulnar nerve with inferior ulnar collateral artery is safe and effective for the treatment of cubital tunnel syndrome.


Assuntos
Síndrome do Túnel Ulnar/cirurgia , Descompressão Cirúrgica , Procedimentos Neurocirúrgicos/métodos , Nervo Ulnar/cirurgia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Ulnar
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