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1.
Eur J Nutr ; 59(4): 1345-1356, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31098661

RESUMO

PURPOSE: This study aimed to explore effects of maternal folic acid (FA) supplementation during pregnancy on neurodevelopment in 1-month-old infants and to determine whether effects may be related to maternal circulating inflammatory cytokine concentrations. METHODS: This birth cohort study recruited 1186 mother-infant pairs in Tianjin, China, between July 2015 and July 2017. The women completed interviewer-administered questionnaires on their lifestyles and FA supplementation during pregnancy. Neurodevelopment was assessed in 1-month-old infants using a standard neuropsychological examination table. In 192 women, serum homocysteine (Hcy) and inflammatory cytokine concentrations were measured at 16-18 weeks of gestation. RESULTS: The infants whose mothers took FA supplements during pregnancy had a significantly higher development quotient (DQ) compared with those whose mothers were non-users (P < 0.05). After adjustment for maternal characteristics, supplementary FA use for 1-3 months, 3-6 months, and > 6 months were associated with the increases of 7.7, 11.0, and 7.4 units in the scale of infant DQ score compared with women reporting no supplement use, respectively (P < 0.05). FA supplementation was associated with a decreased serum concentration of Hcy (ß = [Formula: see text] 0.19), which was correlated with women's serum inflammatory cytokine concentrations at 16-18 weeks of gestation (ß = 0.57). Serum inflammatory cytokine concentrations were inversely related to DQ score in the 1-months-old offspring (ß = [Formula: see text] 0.22). CONCLUSIONS: Maternal FA supplementation during pregnancy favors neurodevelopment in the offspring at 1-month-old. This association may be mediated by changes in serum Hcy and inflammatory cytokine concentrations throughout pregnancy.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Desenvolvimento Infantil/efeitos dos fármacos , Suplementos Nutricionais , Ácido Fólico/farmacologia , Mães/estatística & dados numéricos , Adulto , China , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Gravidez , Estudos Retrospectivos
2.
Biomed Environ Sci ; 30(10): 737-748, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29122094

RESUMO

OBJECTIVE: To investigate the status of folic acid (FA) supplementation and determinants of its use in pregnant Chinese women. METHODS: In this cross-sectional study, questionnaires were used to collect information of participants and FA supplementation. Women were recruited between 6 and 12 weeks postpartum in Tianjin, China, between July 2015 and July 2016. RESULTS: A total of 1,921 women were recruited in the study. Approximately 93.1% of the study participants used FA, while 14.4% of the women taking FA from three months prior to preconception to three months post-conception. Women who took FA for three months prior to preconception through at least three months into their pregnancy were more likely to be between 30 and 34 years old (OR = 2.91, 95% CI: 1.15, 7.33), employed (OR = 2.07, 95% CI: 1.17, 3.67), primigravida (OR = 5.20, 95% CI: 3.02, 8.96), married to spouses with an intermediate education level (OR = 2.92, 95% CI: 1.45, 5.89), and earn a high family income (OR = 3.19, 95% CI: 1.57, 6.49). CONCLUSION: The prevalence of periconceptional FA intake was far below the requirements of the National Health and Family Planning Commission of China; therefore, knowledge of FA supplementation should be strengthened among women who are or planning to become pregnant.


Assuntos
Suplementos Nutricionais , Ácido Fólico/administração & dosagem , Vitaminas/administração & dosagem , Adolescente , Adulto , China , Estudos Transversais , Coleta de Dados , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Defeitos do Tubo Neural , Gravidez , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
3.
Hu Li Za Zhi ; 63(2): 49-57, 2016 Apr.
Artigo em Zh | MEDLINE | ID: mdl-27026557

RESUMO

BACKGROUND: Up to 11% of women with mastitis develop a breast abscess, which obviously affects breastfeeding. Therefore, this is a potentially significant issue for women's health. Women with breast abscesses suffer from severe pain. Pain is the most significant factor causing the termination of breastfeeding. The experience of women with breast abscesses who continued to breastfeed may provide valuable insights/guidance to women who are currently in the same or similar situations. PURPOSE: This study explores the continuous breastfeeding experience of women with breast abscesses. METHODS: We collected qualitative data from 10 qualified female participants using 60-90 minute, in-depth interviews that were conducted between April 2012 and June 2012 in a central medical center. All interviews were recorded and transcribed verbatim. Content analysis was used to analyze and categorize the major themes. RESULTS: Results were generalized into the following seven themes: (1) experiencing uncomfortable breast pain; (2) feeling helpless to manage the abnormal breast symptoms; (3) relying on the concept of motherhood to support continued breastfeeding; (4) feeling shocked about the process of diagnosis and treatment; (5) facing the doubts and difficulties regarding continuing to breastfeed; (6) experiencing the assistance of the support system for breastfeeding; (7) returning to a normal pattern of life. CONCLUSIONS/IMPLICATIONS FOR PRACTICE: The findings provide nurses with a deeper understanding of the biological and psychological behaviors and social support system experiences of women with breast abscesses who continue to breastfeed. Study results may serve as a reference for nurses in providing mother-centered breastfeeding care.


Assuntos
Abscesso/psicologia , Doenças Mamárias/psicologia , Aleitamento Materno , Adulto , Feminino , Humanos , Pesquisa Qualitativa
4.
Macromol Rapid Commun ; 36(5): 490-5, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25619384

RESUMO

Low-molecular-weight poly(ethylene glycol) (PEG) is deliberately incorporated into synthesized swellable poly(ethylene oxide) (PEO) membranes via a facile post-treatment strategy. The membranes exhibit both larger fractional free volume (FFV) and a higher content of CO2-philic building units, resulting in significant increments in both CO2 permeability and CO2/H2 selectivity. The separation performance correlates nicely with the microstructure of the membranes. This study may provide useful insights in the formation and mass transport behavior of highly efficient polymeric membranes applicable to clean energy purification and CO2 capture, and possibly bridge the material-induced technology gap between academia and industry.


Assuntos
Dióxido de Carbono/isolamento & purificação , Membranas Artificiais , Polietilenoglicóis/química , Polímeros/química , Transporte Biológico , Dióxido de Carbono/química , Peso Molecular , Permeabilidade
5.
Phytochemistry ; 225: 114186, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38878944

RESUMO

The ethanol extract of the whole plant of Delphinium trichophorum Franch was subjected to a phytochemical study, leading to the isolation of ten unprecedented diterpenoid alkaloids, including nine delnudine-type C20-diterpenoid alkaloids named trichophodines A-I and one kusnezoline-type C20-diterpenoid alkaloid named trichophozine A. Additionally, seven known compounds were also identified. Their structures were elucidated on the basis of extensive spectroscopic analysis, including HSQC, HMBC, 1H-1H COSY, NOESY and X-ray crystallographic analysis. Most isolated compounds were screened for inhibitory activities against LPS-induced NO production in RAW 264.7 macrophage cells and acetylcholinesterase inhibitory effects. Guan-fu base V exhibited potent inhibitory activity against acetylcholinesterase, demonstrating an inhibitory rate of 53.81% at a concentration of 40 µM.

6.
Neural Regen Res ; 18(8): 1657-1665, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36751776

RESUMO

There is growing evidence that long-term central nervous system (CNS) inflammation exacerbates secondary deterioration of brain structures and functions and is one of the major determinants of disease outcome and progression. In acute CNS injury, brain microglia are among the first cells to respond and play a critical role in neural repair and regeneration. However, microglial activation can also impede CNS repair and amplify tissue damage, and phenotypic transformation may be responsible for this dual role. Mesenchymal stem cell (MSC)-derived exosomes (Exos) are promising therapeutic agents for the treatment of acute CNS injuries due to their immunomodulatory and regenerative properties. MSC-Exos are nanoscale membrane vesicles that are actively released by cells and are used clinically as circulating biomarkers for disease diagnosis and prognosis. MSC-Exos can be neuroprotective in several acute CNS models, including for stroke and traumatic brain injury, showing great clinical potential. This review summarized the classification of acute CNS injury disorders and discussed the prominent role of microglial activation in acute CNS inflammation and the specific role of MSC-Exos in regulating pro-inflammatory microglia in neuroinflammatory repair following acute CNS injury. Finally, this review explored the potential mechanisms and factors associated with MSC-Exos in modulating the phenotypic balance of microglia, focusing on the interplay between CNS inflammation, the brain, and injury aspects, with an emphasis on potential strategies and therapeutic interventions for improving functional recovery from early CNS inflammation caused by acute CNS injury.

7.
Zhonghua Yan Ke Za Zhi ; 48(9): 799-803, 2012 Sep.
Artigo em Zh | MEDLINE | ID: mdl-23141574

RESUMO

OBJECTIVE: To observe the characters of EPSC-IPSC induced by paired-pulse stimulation of rat visual cortex layer II/III pyramidal neurons during critical period of visual development, and discuss their relationships, to discuss the role of short-term synaptic plasticity in the critical period of visual development of rats. METHODS: Thirty Wistar rats were used, they were divided into P10-P12, P14-P16, P21-P23, P28-P30, P35-P37 five groups, n = 6. Whole-cell voltage clamp recording was performed, the membrane potential was clamped on -50 mV, 0 mV respectively to separate EPSC and IPSC. We set the PPR as the observation indicator, analyzed the developmental features of EPSC and IPSC induced by paired-pulse stimulation of different groups. RESULTS: The PPR of layer II/III pyramidal neurons in group P10-P12, P14-P16, P21-P23, P28-P30, P35-P37 was 0.43 ± 0.08, 0.07 ± 0.08, 0.10 ± 0.10, 0.20 ± 0.07, 0.22 ± 0.12 respectively. The PPR of group P14-P16 decreased, the difference was statistically significant compared with the group before eyes open (t = -3.13, P = 0.04). The PPR of corresponding groups was 0.6036 ± 0.3021, 0.2830 ± 0.0504, 0.0287 ± 0.0907, -0.0449 ± 0.1443, -0.3089 ± 0.05553 respectively (F = 5.0799, P = 0.0037), the PPR of IPSC gradually reduced with age, and turned negative from the P28-P30 group, changed from PPF to PPD. CONCLUSIONS: The PPR of EPSC response to visual stimuli rapidly, but did not change significantly in the critical period of visual development (P19-P32). The short-term depression of IPSC increased gradually from the eyes open to the end of the critical period of visual development, which may play a more important role in the process of layer II/III pyramidal neurons maturation and the critical period of visual development ending.


Assuntos
Potenciais Pós-Sinápticos Excitadores , Plasticidade Neuronal/fisiologia , Células Piramidais/fisiologia , Córtex Visual/fisiologia , Animais , Período Crítico Psicológico , Neurônios , Ratos , Ratos Wistar
8.
Int J Ophthalmol ; 14(4): 582-588, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33875952

RESUMO

AIM: To compare the outcomes between early surgery and late surgery for intermittent exotropia (IXT) with a Meta-analysis. METHODS: Scientific databases including PubMed, Embase, Web of Science, Cochrane and China National Knowledge Infrastructure were searched prior to December 16, 2019. From this broad database search, we performed some Meta-analysis including eleven independent studies, to further evaluate the outcome(s) when comparing early versus late surgery for IXT. The boundaries between early and late surgery and the surgery methods were not inconsistent, so subgroup analyses were conducted by different boundaries of age at surgery and different surgical approaches. The pooled odds ratios (ORs) and the 95% confidence interval (CI) were estimated according to the random-effects model for high heterogeneity between studies. RESULTS: Eleven retrospective studies were included in this Meta-analysis. No significant difference between early and late surgery was observed for IXT patients (ORFirst follow-up=0.88, 95%CI 0.53-1.44, P=0.61; ORFinal follow-up=1.48, 95%CI 0.94-2.31, P=0.09). However, sensitivity analysis performed by sequentially omitting individual studies showed that the final follow-up result was not stable. Subgroup analyses revealed that an earlier surgical procedure could lead to a better outcome in the 4-year boundary subgroup as well as the bilateral lateral rectus recession (BLR) subgroup for the final follow-up (OR4y=2.64, 95%CI 1.57-4.44, P=0.00; ORBLR=2.25, 95%CI 1.36-3.74, P=0.00). CONCLUSION: Early surgery for IXT provides a better long term follow-up outcome when patients are younger than 4 years old or choose the BLR surgical method.

9.
Biomed Environ Sci ; 32(10): 730-738, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31843043

RESUMO

OBJECTIVE: To explore the interactions between pre-pregnancy body mass index (BMI) and age on offspring neuropsychological development from 1 to 24 months in China. METHODS: In this birth cohort study, a total of 2,253 mother-child pairs were enrolled in Tianjin, China, between July 2015 and May 2018. The China Developmental Scale for Children was used to assess developmental quotient (DQ) of children aged from 1 to 24 months. RESULTS: Mixed-models analysis revealed significant age × pre-pregnancy BMI interactions for total DQ and five neurobehavioral domains (gross motor, fine motor, adaptive, language, and social; P < 0.001). Age × pre-pregnancy BMI ⪖ 25 kg/m2 was associated with a negative effect on total DQ and five neurobehavioral domains, as compared to pre-pregnancy BMI < 25 kg/m2 (P < 0.01). Multiple comparisons showed pre-pregnancy BMI ⪖ 25 kg/m2 of mothers had a positive effect on child total DQ at the age of 1 month but a negative effect at 24 months (P < 0.05). CONCLUSION: This study supported the age × pre-pregnancy BMI interaction on offspring neuropsychological development. It also revealed a short-term positive impact of high pre-pregnancy BMI on neuropsychological development at 1 month of age, but a long-term negative effect (from 1 to 24 months).


Assuntos
Índice de Massa Corporal , Desenvolvimento Infantil , Adulto , China , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Adulto Jovem
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(9): 1983-6, 2008 Sep.
Artigo em Zh | MEDLINE | ID: mdl-19093544

RESUMO

The intermediate decomposition products of methanol (CH3OH) in an AC discharge were diagnosticated via concentration modulation spectroscopy. Several main vibrational bands of CO Angström beta 1 sigma+ -alpha 1pi system, CH alpha 2 delta-X2pi system at 430 nm and beta 2 sigma- -X2pi at 390 nm, as well as CHO (329.82 nm), CH2O (369.8 nm), CH3O (347.8 nm) and Balmer series spectra of H atom were identified in the region between 300 and 670 nm. Furthermore, the dependences of the emission spectral intensities of the intermediate decomposition products on the discharge voltage and parent gas pressure were investigated in detail. The experiments indicated that the relative population ratio of CO (beta 1 sigma+) and H increases with increasing discharge voltage more quickly than that of CH (alpha 2 delta). Several possible reaction passages were given and discussed. Additionally, the vibrational and rotational temperatures of CH (alpha 2 delta) were determined to be about 4200 and 1100 K respectively, and the vibrational temperatures of CO (beta 1 sigma+) were determined to be about 2500 K by analyzing the intensity distribution using LIFEBASE computer program. The decomposition mechanism of methanol in the discharge plasma was discussed as well.

11.
Medicine (Baltimore) ; 97(11): e9584, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29538216

RESUMO

This study aims to investigate the menstrual recovery outcome of scar pregnancy patients who received uterine artery embolization combined with curettage, and its influencing factors.The data of 119 patients with scar pregnancy, who received uterine artery embolization combined with curettage between December 2012 and December 2016 in Henan Provincival People's Hospital, were collected. The menstruation recovery of these patients was followed up, and factors that have influence on menstrual blood volume were analyzed using SPSS V.17.0.Follow-up data were available in 101/119 (84.9%) women. The median follow-up time was 22.7 months (range: 1.6-50.6 months); 58 (57.4%) patients had reduced menstrual blood volume, and 2 patients (2%) had amenorrhea. The proportion of patients with reduced menstrual blood volume, who were embolized with polyvinyl alcohol (PVA), PVA combined with gelatin sponge, and gelatin sponge between < and ≥33 years old was 41.7% versus 66.7%, 40% versus 57.1% and 60.6% versus 68.0%. The average age of patients with reduced menstrual blood volume (34.3 years) was greater than patients with normal menstrual blood volume (31.4 years), but the difference was not statistically significant (P = .07).Reduced menstrual blood volume can occur in scar pregnancy patients who received uterine artery embolization combined with curettage. The influence of the embolic agent PVA on menstrual blood volume depends on age, but the difference was not statistically significant.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Curetagem/efeitos adversos , Distúrbios Menstruais , Complicações Pós-Operatórias , Gravidez Ectópica , Embolização da Artéria Uterina/métodos , Ruptura Uterina/prevenção & controle , Aborto Legal/efeitos adversos , Aborto Legal/métodos , Adulto , Cesárea/efeitos adversos , Cicatriz/etiologia , Cicatriz/patologia , Cicatriz/fisiopatologia , Curetagem/métodos , Feminino , Humanos , Efeitos Adversos de Longa Duração/diagnóstico , Distúrbios Menstruais/diagnóstico , Distúrbios Menstruais/etiologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/fisiopatologia , Gravidez , Gravidez Ectópica/diagnóstico , Gravidez Ectópica/cirurgia , Recuperação de Função Fisiológica , Ruptura Uterina/etiologia
12.
J Hazard Mater ; 324(Pt B): 250-257, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27817874

RESUMO

The environmental contaminants phthalic acid esters (PAEs) were determined by aromatic hydroxylation fluorimetry combined with heterogeneous photo-Fenton process in the presence of vermiculite supported BiFeO3 (VMT-BiFeO3). In strong alkaline solution, PAEs were hydrolyzed into phthalates with no fluorescence, which then reacted with hydroxyl free radicals produced in photo-Fenton process catalyzed by VMT-BiFeO3 to form the fluorescent hydroxyl phthalates. The fluorescence intensity was proportional to the concentration of PAEs with the maximum excitation and emission wavelength of 300nm and 417nm, respectively. A good linear relationship can be obtained in the range of 3.8×10-7 to 4.8×10-5molL-1 for DEP with correlation coefficient of 0.9997, and the sensitivity of the method was high with detection limit of 5.43×10-8molL-1. The method has been successfully applied to determine total PAEs in airborne particulates with satisfactory results.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(9): 1594-7, 2006 Sep.
Artigo em Zh | MEDLINE | ID: mdl-17112024

RESUMO

An experimental apparatus using an AC discharge was developed for producing molecular ion beam. The emission spectral intensity of N2+ is stronger than that of N2, and a very high ratio of N2+ (B)/N2 (C) up to 6:1, was achieved in N2 discharge. The effects and processes of N2 discharge, and the concentration modulation spectra were studied. The vibrational temperature and rotational temperature of N2+ molecular ions beam were calculated to be 3 310 and 282 K respectively from the emission spectra.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(8): 1250-2, 2005 Aug.
Artigo em Zh | MEDLINE | ID: mdl-16329493

RESUMO

The molecular cation CO+ is a very important transient molecular radical, and the spectra of the ion has been investigated by numerous researchers. Optical-heterodyne-magnetic-rotation-enhanced velocity modulation spectroscopy(OH-MR-VMS) was employed to measure the comet-tail system (A2 pi(i)-X2 sigma+) of 12C16O+ molecular ion. The vibrational rotation absorption spectra wereobserved in the near-infrared region, including three bands of (0, 3), (1, 4) and (3, 6). A set of precise molecular constants for the A2 pi(i) (v' = 0, 1, 3) were determined using the least-squares fit. This experiment has further proved that OH-MR-VMS is very valuable in measuring absorption spectra of molecular ions.


Assuntos
Cátions/química , Radicais Livres/química , Espectroscopia de Luz Próxima ao Infravermelho , Análise dos Mínimos Quadrados , Termodinâmica
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(1): 65-8, 2005 Jan.
Artigo em Zh | MEDLINE | ID: mdl-15852821

RESUMO

The CN radical was produced by Penning AC discharge of the mixture of trace acetonitrile (36 Pa) and helium (660 Pa) and the ro-vibrational spectra were measured by optical heterodyne magnetic rotation enhanced concentration modulation spectroscopy in the range of 16 850-17 480 cm(-1). 138 lines and 118 lines were assigned to the (6, 1) and (7, 2) bands in red system A 2IIi-X 2sigma+ of CN respectively, while others were due to (8, 3) band in CN red system and C2 Swan band system. More accurate molecular constants of A 2IIi (v = 6, 7) state and perturbation parameters zeta and eta between A and X states were derived based on nonlinear least-square fitting, individually, by diagonalizing the effective Hamiltonian matrix involving the perturbation elements of two electronical states and the standard deviation of fitting was less than the experimental uncertainty 0.007 cm(-1), which implied the accuracy of our results.


Assuntos
Cianetos/química , Radicais Livres/química , Análise Espectral/métodos , Acetonitrilas/química , Algoritmos , Isótopos de Carbono , Hélio/química , Modelos Químicos , Análise Espectral/instrumentação , Vibração
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(3): 454-7, 2003 Jun.
Artigo em Zh | MEDLINE | ID: mdl-12953512

RESUMO

The principle and technical characters of far infrared laser magnetic resonance (FIRLMR) spectrometer built up in China are introduced. A CO2 transversely pumped far infrared laser is adopted. In order to obtain high sensitivity, the sample absorption cell is placed in the FIR laser cavity and separated from laser gain cavity with thin polypropylene film. The spectrometer can be employed to study short lived free radicals. The spectra of many transient free radicals including CCH, CF and CH2 have been detected by the spectrometer. These transients are generated by mixing CH4 with the fluorine atoms produced with microwave discharge.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Lasers , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Carbono/química , Dióxido de Carbono , Espectroscopia de Ressonância de Spin Eletrônica/instrumentação , Radicais Livres/química , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Vibração
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 22(4): 569-72, 2002 Aug.
Artigo em Zh | MEDLINE | ID: mdl-12938367

RESUMO

A new method for the calibration of wavelength in a measurement of high resolution molecular absorption spectra by referring the standard spectrum of iodine molecule is presented in this paper. Segment offset is employed in the calibration of wavelength, while the data smoothing, baseline determining and peak fitting are applied to preprocess the spectral data. A visual software is provided for automatically calibrating wavelength with a friendly style of mutual dialogue between human and computer. The software has been used to calibrate the absorption spectra of N2+ molecular ion in the visible region 16,422-17,896 cm-1, the absolute accuracy is about 0.006 cm-1.


Assuntos
Iodo/química , Espectroscopia de Ressonância Magnética/métodos , Processamento de Sinais Assistido por Computador , Calibragem , Sensibilidade e Especificidade , Software
18.
Huan Jing Ke Xue ; 34(2): 494-8, 2013 Feb.
Artigo em Zh | MEDLINE | ID: mdl-23668114

RESUMO

This paper was to select a small-medium sized City, Changji city, over the arid region, study the distribution of platinum group metals(PGEs) contents and influencing factors in snowfall and snow cover. Samples were analysed by ICP-MS. The results revealed that the annual contents of Rh, Pd and Pt in snowfall were on the average value of 0.43 ng.L-1 ranging from not detected to 2.24 ng.L-1 , 60.07 ng.L-1 ranging from 46.66 to 84.25 ng.L-1 and 4.54 ng.L-1 ranging from 3.02 ng.L-1 to 6.38 ng.L-1 respectively. The difference of PGEs levels was found in different occurrences of snowfall, tended to increase before snowfall due to the longer arid days. PGEs contents maybe influenced by the amount of snowfall, the less snowfall, the higher PGEs contents reflected. The annual levels of Rh, Pd and Pt in snow cover were in the range of 2.50-18.80 ng.L-1 (av. 6.65 ng.L-1), 46.83-199.20 ng.L-1 (av. 83.45 ng.L-1) ,4. 27-13.78 ng.L-1 (av. 8.17 ng.L-1) respectively. PGEs content in snow cover were far higher than that of snowfall, PGEs in snowfall were only obtained from atmospheric PGEs rinsed by single time of snowfall, while PGEs were not only from the accumulation of PGEs in frequent times of snowfall and the snow cover under the long time exposure, but also continuously accepted the PGEs from atmospheric dry deposition. PGEs content of snow cover in all sampling sites were demonstrated as follows: traffic area > residential-culture-education district > square of park > suburban farmland. the input way of PGEs in snow cover was found a remarkable difference with the amount of input within different function areas, which was the main reason caused that PGEs content of snow cover in each function area varied and had a certain regularity.


Assuntos
Poluentes Ambientais/análise , Platina/análise , Rubídio/análise , Neve , China , Cidades , Monitoramento Ambiental
19.
Huan Jing Ke Xue ; 32(9): 2676-80, 2011 Sep.
Artigo em Zh | MEDLINE | ID: mdl-22165238

RESUMO

In order to study temporal variation characteristics and influencing mechanism of platinum group elements (PGEs) in road dust, 24 seasonal samples and 18 inter annual samples of road dust were collected from roads in Shanghai, and were analysed by ICP-MS following aqua regia digestion. The results are as following: average concentrations of PGEs in spring, summer, autumn, winter were 10.40 (6.06-17.28) ng/g, 11.60 (5.52-20.11) ng/g, 32.91(18.53-61.05) ng/g, 32.33 (16.29-47.89) ng/g with Rh, 52.99 (27.48-100.2) ng/g, 53.77 (20.42-72.31) ng/g, 125.50 (75.41-247.8) ng/g, 132.59 (78.45-199.9) ng/g with Pd, 13.58 (7.96-30.97) ng/g, 13.24 (6.40-17.96) ng/g, 48.20 (25.07-122.9) ng/g, 53.63 (22.11-107.7) ng/g with Pt. PGEs concentrations had obvious seasonal change that were lower in spring and summer, higher in autumn and winter, and rainfall were main effect factors. The comparison of levels of PGEs between 2003 and 2007 showed that PGEs concentrations in road dust had increased over the period of 4 years with 11% - 19% of average annual growth rate because of the rapid increase in the number of vehicles in Shanghai. Meanwhile, the average PGEs ratios of road dust samples from Shanghai were inconsistent with Ely's result. These differences were contributed by the change of VECs type.


Assuntos
Poeira/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Platina/análise , China , Estações do Ano , Emissões de Veículos/análise
20.
Huan Jing Ke Xue ; 30(10): 3050-4, 2009 Oct 15.
Artigo em Zh | MEDLINE | ID: mdl-19968129

RESUMO

In order to study accumulation characteristics of PGEs in multimedia from road environment, samples of road dust, roadside soil and plant were collected from five roads in Shanghai, and were analysed by ICP-MS following aqua regia digestion. The results are as following: average concentrations of Rh, Pd and Pt were 24.92, 88.39, 22.28 ng/g in dust, 3.64, 17.45, 0.97 ng/g in soil and 2.66, 6.39, 0.57 ng/g in plant, respectively. The concentrations of PGEs in dust were higher than that in soil and in plant. Meanwhile, PGEs concentrations in plant were lower than that in dust, and closed to that of soil. The implementation of the automobile emission standard only in central city of Shanghai didn't cause obvious correlation between PGEs in multimedia and traffic volume. The plant adsorption capacity for PGEs of road dust showed: Pt > Pd > Rh, while its absorptive capacity for PGEs of soil was: Pd > Rh > Pt. PGEs ratios in multimedia were not completely coincident but in the range of PGEs ratios of road dust in Shanghai, which indicated a common traffic-related source of these metals.


Assuntos
Poeira/análise , Poluentes Ambientais/análise , Paládio/análise , Platina/análise , Ródio/análise , China , Monitoramento Ambiental , Plantas/química , Poluentes do Solo/análise
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