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1.
PLoS One ; 12(12): e0189726, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29261745

RESUMO

Water contamination by heavy metals from industrial activities is a serious environmental concern. To mitigate heavy metal toxicity and to recover heavy metals for recycling, biomaterials used in phytoremediation and bio-sorbent filtration have recently drawn renewed attention. The filamentous protonemal cells of the moss Funaria hygrometrica can hyperaccumulate lead (Pb) up to 74% of their dry weight when exposed to solutions containing divalent Pb. Energy-dispersive X-ray spectroscopy revealed that Pb is localized to the cell walls, endoplasmic reticulum-like membrane structures, and chloroplast thylakoids, suggesting that multiple Pb retention mechanisms are operating in living F. hygrometrica. The main Pb-accumulating compartment was the cell wall, and prepared cell-wall fractions could also adsorb Pb. Nuclear magnetic resonance analysis showed that polysaccharides composed of polygalacturonic acid and cellulose probably serve as the most effective Pb-binding components. The adsorption abilities were retained throughout a wide range of pH values, and bound Pb was not desorbed under conditions of high ionic strength. In addition, the moss is highly tolerant to Pb. These results suggest that the moss F. hygrometrica could be a useful tool for the mitigation of Pb-toxicity in wastewater.


Assuntos
Briófitas/metabolismo , Chumbo/metabolismo , Adsorção , Parede Celular/metabolismo , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Concentração Osmolar , Espectrometria por Raios X
2.
Ann Vasc Dis ; 8(2): 110-2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26131032

RESUMO

Chylothorax is a rare but serious complication of thoracic aortic surgery, leading to malnutrition, respiratory insufficiency, and prolonged hospital stay. In this article, we describe the successful treatment of a case of intractable chylothorax by lipiodol lymphography. The patient was a 39-year-old man who underwent descending aortic replacement for a remaining dissected aneurysm after total arch replacement. Chylothorax developed postoperatively. After complete oral intake cessation, total parenteral nutrition, and plasmatic factor XIII administration, lipiodol lymphography detected the chyle leakage location and subsequently decreased pleural effusion. The patient recovered uneventfully and was discharged on postoperative day 30 without any complications.

3.
Chemosphere ; 87(8): 886-93, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22342335

RESUMO

Reactive volatile organic compounds (VOCs) are known to affect atmospheric chemistry. Biogenic VOCs (BVOCs) have a significant impact on regional air quality due to their large emission rates and high reactivities. Diterpenes (most particularly, kaur-16-ene) were detected in all of the 205 enclosure air samples collected over multiple seasons at two different sites from Cryptomeria japonica and Chamaecyparis obtusa trees, the dominant coniferous trees in Japan,. The emission rate of kaur-16-ene, was determined to be from 0.01 to 7.1 µg dwg(-1) h(-1) (average: 0.61 µg dwg(-1) h(-1)) employing branch enclosure measurements using adsorbent sampling followed by solid phase-liquid extraction techniques. The emission rate was comparable to that of monoterpenes, which is known major BVOC emissions, collected from the same branches. In addition, total emission of kaur-16-ene at 30°C was estimated to exceed that of total anthropogenic VOC emissions.


Assuntos
Chamaecyparis/química , Cryptomeria/química , Diterpenos/análise , Árvores/química , Compostos Orgânicos Voláteis/análise , Diterpenos/química , Diterpenos/isolamento & purificação , Japão , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação , Volatilização
4.
Anal Chem ; 80(16): 6267-73, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18646776

RESUMO

GEOTRACES is an international research project on marine biogeochemical cycles of trace elements and their isotopes. GEOTRACES key trace metals in seawater are Al (8-1000 ng/kg), Mn (4-300 ng/kg), Fe (1-100 ng/kg), Cu (30-300 ng/kg), Zn (3-600 ng/kg), and Cd (0.1-100 ng/kg), of which global oceanic distribution will be determined on a number of research cruises. This work introduces a novel method of solid-phase extraction to determine Al, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb in seawater by adjusting the pH of the sample to 6 and carrying out a single preconcentration step. The trace metals were collected from approximately 120 mL of seawater using a column of a chelating resin containing the ethylenediaminetriacetic acid functional group and eluted with approximately 15 mL of 1 M HNO3. Mn and Fe in the eluate were measured by inductively coupled plasma mass spectrometry (ICPMS) using the dynamic reaction cell mode, and the other metals were measured using the standard mode. Using this procedure, the trace metals were collected quantitatively, while >99.9% of alkali and alkaline earth metals in seawater were removed. The procedural blank was <7% of the mean concentration in deep ocean waters, except 16% for Pb. The overall detection limit was <14% of the mean concentration in deep ocean waters. The RSD was <9%. Our values for the trace metals in the certified reference materials of seawater NASS-5 and nearshore seawater CASS-4 agreed with the certified values (except that there is no certified value for Al). This method was also successfully applied to the reference materials of open-ocean seawater produced by the SAFe program. Our Fe concentrations were 5.9 +/- 0.7 ng/kg for surface water (S1) and 50.4 +/- 2.9 ng/kg for deep water (D2), which are in agreement with the interlaboratory averages of 5.4 +/- 2.4 and 50.8 +/- 9.5 ng/L, respectively. The data for other metals were oceanographically consistent.

5.
Anal Chim Acta ; 594(1): 52-60, 2007 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-17560385

RESUMO

A new technique for the determination of suspended particulate trace metals (P-metals >0.2 microm), such as Co, Ni, Cu, Zn, Cd and Pb, in open ocean seawater has been developed by using microwave digestion coupled with flow injection inductively coupled plasma mass spectrometry (FI-ICP-MS). Suspended particulate matter (SPM) was collected from 500 mL of seawater on a Nuclepore filter (0.2 microm) using a closed filtration system. Both the SPM and filter were completely dissolved by microwave digestion. Reagents for the digestion were evaporated using a clean evaporation system, and the metals were redissolved in 0.8 M HNO3. The solution was diluted with buffer solution to give pH 5.0 and the metals were determined by FI-ICP-MS using a chelating adsorbent of 8-hydroxyquinoline immobilized on fluorinated metal alkoxide glass (MAF-8HQ). The procedure blanks with a filter were found to be 0.048+/-0.008, 10.3+/-0.3, 0.27+/-0.05, 3.3+/-1.8, 0.02+/-0.03 and 0.85+/-0.09 ng L(-1) for Co, Ni, Cu, Zn, Cd and Pb, respectively (n=14). Detection limits defined as 3 times the standard deviation of the blanks were 0.023, 0.90, 0.14, 5.3, 0.078 and 0.28 ng L(-1) for Co, Ni, Cu, Zn, Cd and Pb, respectively. Accuracy was evaluated using certified reference materials of chlorella (NES CRM No. 3) and marine sediment (HISS-1). The method was applied to the determination of vertical distributions for P-Co, Ni, Cu, Zn, Cd and Pb in the Western North Pacific.


Assuntos
Filtração/métodos , Espectrometria de Massas/métodos , Metais/análise , Micro-Ondas , Água do Mar/química , Oligoelementos/análise
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