Base de dados : MEDLINE
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[PMID]:28992483
[Au] Autor:Ma J; Yang Y; Jiang X; Xie Z; Li X; Chen C; Chen H
[Ad] Endereço:State Key Laboratory of Heavy Oil Processing, State Key Laboratory of Petroleum Pollution Control, Beijing Key Lab of Oil & Gas Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China. Electronic address: rubpmj@sina.com.
[Ti] Título:Impacts of inorganic anions and natural organic matter on thermally activated persulfate oxidation of BTEX in water.
[So] Source:Chemosphere;190:296-306, 2018 Jan.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The present study investigated the impacts of water matrix constituents (CO , HCO , Cl , Br , PO , HPO , H PO , NO , SO and natural organic matters (NOM) on the oxidation of a mixture of benzene, toluene, ethylbenzene, and xylenes (BTEX) by thermally activated persulfate (PS). In the absence of matrix constituents, the BTEX oxidation rates decreased in the following order: xylenes > toluene ≈ ethylbenzene > benzene. HCO /CO and NOM inhibited the BTEX oxidation and the inhibiting effects became more pronounced as the HCO /CO /NOM concentration increased. SO , NO , PO and H PO did not affect the BTEX oxidation while HPO slightly inhibited the reaction. The impacts of Cl and Br were complex. Cl inhibited the benzene oxidation while 100 mM and 500 mM of Cl promoted the oxidation of m-xylene and p-xylene. Br completely suppressed the benzene oxidation while 500 mM of Br strongly promoted the oxidation of xylenes. Detailed explanations on the influence of each matrix constituent were discussed. In addition, various halogenated degradation byproducts were detected in the treatments containing Cl and Br . Overall, this study indicates that some matrix constituents such as NOM, HCO , CO , H PO , Cl and Br may reduce the BTEX removal efficiency of sulfate radical-based advanced oxidation process (SR-AOP) and the presence of Cl and Br may even lead to the formation of toxic halogenated byproducts.
[Mh] Termos MeSH primário: Derivados de Benzeno/química
Benzeno/química
Sulfatos/química
Tolueno/química
Água/química
Xilenos/química
[Mh] Termos MeSH secundário: Substâncias Húmicas
Compostos Inorgânicos/farmacologia
Íons
Cinética
Oxirredução
Poluentes Químicos da Água/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Benzene Derivatives); 0 (Humic Substances); 0 (Inorganic Chemicals); 0 (Ions); 0 (Sulfates); 0 (Water Pollutants, Chemical); 0 (Xylenes); 0 (sulfate radical); 059QF0KO0R (Water); 3FPU23BG52 (Toluene); J64922108F (Benzene); L5I45M5G0O (ethylbenzene)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180214
[Lr] Data última revisão:
180214
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171010
[St] Status:MEDLINE


  2 / 1462 MEDLINE  
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[PMID]:28734030
[Au] Autor:Nayebi N; Cetinel S; Omar SI; Tuszynski JA; Montemagno C
[Ad] Endereço:Ingenuity Lab, University of Alberta, Edmonton, Alberta, Canada.
[Ti] Título:A computational method for selecting short peptide sequences for inorganic material binding.
[So] Source:Proteins;85(11):2024-2035, 2017 Nov.
[Is] ISSN:1097-0134
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Discovering or designing biofunctionalized materials with improved quality highly depends on the ability to manipulate and control the peptide-inorganic interaction. Various peptides can be used as assemblers, synthesizers, and linkers in the material syntheses. In another context, specific and selective material-binding peptides can be used as recognition blocks in mining applications. In this study, we propose a new in silico method to select short 4-mer peptides with high affinity and selectivity for a given target material. This method is illustrated with the calcite (104) surface as an example, which has been experimentally validated. A calcite binding peptide can play an important role in our understanding of biomineralization. A practical aspect of calcite is a need for it to be selectively depressed in mining sites.
[Mh] Termos MeSH primário: Biologia Computacional/métodos
Compostos Inorgânicos/química
Compostos Inorgânicos/metabolismo
Peptídeos/química
Peptídeos/metabolismo
[Mh] Termos MeSH secundário: Carbonato de Cálcio
Mineração
Simulação de Dinâmica Molecular
Ligação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Inorganic Chemicals); 0 (Peptides); H0G9379FGK (Calcium Carbonate)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171030
[Lr] Data última revisão:
171030
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170723
[St] Status:MEDLINE
[do] DOI:10.1002/prot.25356


  3 / 1462 MEDLINE  
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[PMID]:28651489
[Au] Autor:Tsutsumi K; Matsuya Y; Sugahara T; Tamura M; Sawada S; Fukura S; Nakano H; Date H
[Ad] Endereço:1 Faculty of Health Sciences, Hokkaido University, Sapporo, Japan.
[Ti] Título:Inorganic polyphosphate enhances radio-sensitivity in a human non-small cell lung cancer cell line, H1299.
[So] Source:Tumour Biol;39(6):1010428317705033, 2017 Jun.
[Is] ISSN:1423-0380
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Inorganic polyphosphate is a linear polymer containing tens to hundreds of orthophosphate residues linked by high-energy phosphoanhydride bonds. Polyphosphate has been recognized as a potent anti-metastasis reagent. However, the molecular mechanism underlying polyphosphate action on cancer cells is poorly understood. In this study, we investigated the involvement of polyphosphate in radio-sensitivity using a human non-small cell lung cancer cell line, H1299. We found that polyphosphate treatment decreases cellular adenosine triphosphate levels, suggesting a disruption of energy metabolism. We also found that the induction of DNA double-strand breaks was enhanced in polyphosphate-treated cells after X-ray irradiation and colony formation assay revealed that cell survival decreased compared with that of the control groups. These findings suggest that polyphosphate is a promising radio-sensitizer for cancer cells. Therefore, we hypothesized that polyphosphate treatment disrupts adenosine triphosphate-mediated energy transfer for cellular survival and DNA repair, thereby reducing the cellular capability to resist X-ray irradiation.
[Mh] Termos MeSH primário: Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico
Carcinoma Pulmonar de Células não Pequenas/radioterapia
Metástase Neoplásica/tratamento farmacológico
Metástase Neoplásica/radioterapia
[Mh] Termos MeSH secundário: Trifosfato de Adenosina/metabolismo
Carcinoma Pulmonar de Células não Pequenas/metabolismo
Carcinoma Pulmonar de Células não Pequenas/patologia
Linhagem Celular Tumoral
Sobrevivência Celular/efeitos dos fármacos
Terapia Combinada
Quebras de DNA de Cadeia Dupla/efeitos dos fármacos
Metabolismo Energético/efeitos dos fármacos
Seres Humanos
Compostos Inorgânicos/administração & dosagem
Metástase Neoplásica/patologia
Polifosfatos/administração & dosagem
Tolerância a Radiação/efeitos dos fármacos
Radiossensibilizantes/administração & dosagem
Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Inorganic Chemicals); 0 (Polyphosphates); 0 (Radiation-Sensitizing Agents); 8L70Q75FXE (Adenosine Triphosphate)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170713
[Lr] Data última revisão:
170713
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170628
[St] Status:MEDLINE
[do] DOI:10.1177/1010428317705033


  4 / 1462 MEDLINE  
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[PMID]:28599193
[Au] Autor:Leavey A; Patel S; Martinez R; Mitroo D; Fortenberry C; Walker M; Williams B; Biswas P
[Ad] Endereço:Center for Aerosol Science and Engineering (CASE), Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA.
[Ti] Título:Organic and inorganic speciation of particulate matter formed during different combustion phases in an improved cookstove.
[So] Source:Environ Res;158:33-42, 2017 10.
[Is] ISSN:1096-0953
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Residential solid fuel combustion in cookstoves has established health impacts including bladder and lung cancers, cataracts, low birth weight, and pneumonia. The chemical composition of particulate matter (PM) from 4 commonly-used solid fuels (coal, dung, ambient/dry applewood, and oakwood pellets), emitted from a gasifier cookstove, as well as propane, were examined. Temporal changes between the different cookstove burn-phases were also explored. Normalized concentrations of non-refractory PM , total organics, chloride, ammonium, nitrate, sulfate, and 41 particle-phase polycyclic aromatic hydrocarbons (PAHs) were measured using a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and a Thermal desorption Aerosol Gas chromatograph (TAG), respectively. Coal demonstrated the highest fraction of organic matter in its particulate emission composition (98%), followed by dung (94%). Coal and dung also demonstrated the highest numbers and concentrations of PAHs. While dry applewood emitted ten times lower organic matter compared to ambient applewood, a higher fraction of these organics was composed of PAHs, especially the more toxic ones such as benzo(a)pyrene (9.63ng/L versus 0.04ng/L), and benzo(b)fluoranthene (31.32ng/L versus 0.19ng/L). Data from the AMS demonstrated no clear trends for any of the combustion fuels over the different combustion phases unlike the previously reported trends observed for the physical characteristics. Of the solid fuels, pellets demonstrated the lowest emissions. Emissions from propane were below the quantification limit of the instruments. This work highlights the benefits of incorporating additional metrics into the cookstove evaluation process, thus enriching the existing PM data inventory.
[Mh] Termos MeSH primário: Poluentes Atmosféricos/química
Poluição do Ar em Ambientes Fechados/análise
Monitoramento Ambiental
Compostos Inorgânicos/análise
Compostos Orgânicos/análise
Material Particulado/química
[Mh] Termos MeSH secundário: Poluentes Atmosféricos/análise
Carvão Mineral
Culinária
Fezes
Material Particulado/análise
Madeira
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Air Pollutants); 0 (Coal); 0 (Inorganic Chemicals); 0 (Organic Chemicals); 0 (Particulate Matter)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171120
[Lr] Data última revisão:
171120
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170610
[St] Status:MEDLINE


  5 / 1462 MEDLINE  
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[PMID]:28564625
[Au] Autor:Conca E; Malandrino M; Giacomino A; Buoso S; Berto S; Verplanck PL; Magi E; Abollino O
[Ad] Endereço:Department of Chemistry, University of Turin, Via Giuria 5, 10125 Turin, Italy.
[Ti] Título:Dynamics of inorganic components in lake waters from Terra Nova Bay, Antarctica.
[So] Source:Chemosphere;183:454-470, 2017 Sep.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Water and Suspended Particulate Material (SPM) samples analysed in this work were collected in the austral summer 2011/12 from six shallow Antarctic lakes (Carezza, Edmonson Point 14 and 15a, Gondwana, Inexpressible Island 10b and Tarn Flat 20) of Terra Nova Bay (Northern Victoria Land, Antarctica). The total concentrations of a large suite of inorganic analytes were determined, in order to gain insight into the natural processes regulating species distribution, define natural background values and detect possible present or future local and/or global anthropogenic contamination. Lake water composition was found to be influenced by marine spray, lake geographical position and meltwater input. Seasonal variability was also evaluated for each analyte, and explained considering the natural transport processes involving each species. Multivariate chemometric techniques were used in order to identify groups of samples with similar characteristics and find out similarities and correlations among variables. The variability observed within the water samples is closely connected to the marine aerosol input; hence, it is primarily a consequence of geographical and meteorological factors, such as distance from the ocean and period of year. Higher element concentrations have been found in SPM than in water, suggesting that weathering plays an important role on the chemistry of these lakes or that adsorption processes take place. SPM samples were also examined with a Scanning Electron Microscope (SEM), and many diatoms belonging to different species were detected. No clear evidence of a relevant metal contamination was found in the investigated area.
[Mh] Termos MeSH primário: Baías/química
Compostos Inorgânicos/análise
Lagos/química
Água/química
[Mh] Termos MeSH secundário: Aerossóis/análise
Regiões Antárticas
Diatomáceas
Geografia
Metais/análise
Material Particulado/análise
Estações do Ano
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Aerosols); 0 (Inorganic Chemicals); 0 (Metals); 0 (Particulate Matter); 059QF0KO0R (Water)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170601
[St] Status:MEDLINE


  6 / 1462 MEDLINE  
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[PMID]:28544897
[Au] Autor:Liu Z; Xie Y; Hu B; Wen T; Xin J; Li X; Wang Y
[Ad] Endereço:State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China. Electronic address: liuzirui@mail.iap.ac.cn.
[Ti] Título:Size-resolved aerosol water-soluble ions during the summer and winter seasons in Beijing: Formation mechanisms of secondary inorganic aerosols.
[So] Source:Chemosphere;183:119-131, 2017 Sep.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Size-segregated water-soluble ionic species (WSIs) were measured using an Anderson cascade impactor from Jul. to Aug. 2008 and from Dec. 2009 to Feb. 2010 in urban Beijing. The results showed that fine particles (PM , Dp < 2.1 µm) accounted for ∼49% (summer) and ∼34% (winter) of the total particulate mass, and WSIs accounted for 23-82% of the mass concentration of PM . Secondary inorganic aerosols (SIAs, the sum of SO , NO and NH ) accounted for more than 30% of the fine particles, which were greatly elevated during particle pollution events (PM events), thereby leading to an alteration of the size distributions of SO and NO to nearly single fine-mode distributions peaking at 0.65-2.1 µm. This finding suggests that heterogeneous aqueous reactions were enhanced at high RH values. SIAs also increased during dust events, particularly for coarse mode SO , which indicated enhanced heterogeneous reactions on the dust surface. The positive matrix factorization (PMF) model was used to resolve the bulk mass size distributions into condensation, droplet, and coarse modes, representing the three major sources of the particles. The formation of SO was attributed primarily to in-cloud or aerosol droplet processes during summer (45%), and the heterogeneous reaction of SO on mineral dust surfaces was an important formation pathway during winter (45%). The formation pathways of NO in fine particles were similar to those of SO , where over 30% were formed by in-cloud processes. This work provides important field measurement-based evidence for understanding the formation pathway of secondary inorganic aerosols in the megacity of Beijing.
[Mh] Termos MeSH primário: Poluentes Atmosféricos/análise
Monitoramento Ambiental/métodos
Compostos Inorgânicos/análise
Material Particulado/análise
Água/química
[Mh] Termos MeSH secundário: Aerossóis
Pequim
Poeira
Íons
Tamanho da Partícula
Estações do Ano
Solubilidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Aerosols); 0 (Air Pollutants); 0 (Dust); 0 (Inorganic Chemicals); 0 (Ions); 0 (Particulate Matter); 059QF0KO0R (Water)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171003
[Lr] Data última revisão:
171003
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170526
[St] Status:MEDLINE


  7 / 1462 MEDLINE  
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[PMID]:28437092
[Au] Autor:Bjerknes M; Cheng H; McNitt CD; Popik VV
[Ad] Endereço:Departments of Medicine and Medical Biophysics, University of Toronto , Toronto, Ontario M5S 1A8, Canada.
[Ti] Título:Facile Quenching and Spatial Patterning of Cylooctynes via Strain-Promoted Alkyne-Azide Cycloaddition of Inorganic Azides.
[So] Source:Bioconjug Chem;28(5):1560-1565, 2017 May 17.
[Is] ISSN:1520-4812
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Little is known about the reactivity of strain-promoted alkyne-azide cycloaddition (SPAAC) reagents with inorganic azides. We explore the reactions of a variety of popular SPAAC reagents with sodium azide and hydrozoic acid. We find that the reactions proceed in water at rates comparable to those with organic azides, yielding in all cases a triazole adduct. The azide ion's utility as a cyclooctyne quenching reagent is demonstrated by using it to spatially pattern uniformly doped hydrogels. The facile quenching of cyclooctynes demonstrated here should be useful in other bioorthogonal ligation techniques in which cyclooctynes are employed, including SPANC, Diels-Alder, and thiol-yne.
[Mh] Termos MeSH primário: Alquinos/química
Azidas/química
Compostos Inorgânicos/química
[Mh] Termos MeSH secundário: Catálise
Química Click
Reação de Cicloadição
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkynes); 0 (Azides); 0 (Inorganic Chemicals)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170425
[St] Status:MEDLINE
[do] DOI:10.1021/acs.bioconjchem.7b00201


  8 / 1462 MEDLINE  
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[PMID]:28414730
[Au] Autor:Williams M; Bozhilov K; Ghai S; Talbot P
[Ad] Endereço:Department of Cell Biology and Neuroscience, University of California Riverside, Riverside, California, United States America.
[Ti] Título:Elements including metals in the atomizer and aerosol of disposable electronic cigarettes and electronic hookahs.
[So] Source:PLoS One;12(4):e0175430, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: Our purpose was to quantify 36 inorganic chemical elements in aerosols from disposable electronic cigarettes (ECs) and electronic hookahs (EHs), examine the effect of puffing topography on elements in aerosols, and identify the source of the elements. METHODS: Thirty-six inorganic chemical elements and their concentrations in EC/EH aerosols were determined using inductively coupled plasma optical emission spectroscopy, and their source was identified by analyzing disassembled atomizers using scanning electron microscopy and energy dispersive X-ray spectroscopy. RESULTS: Of 36 elements screened, 35 were detected in EC/EH aerosols, while only 15 were detected in conventional tobacco smoke. Some elements/metals were present in significantly higher concentrations in EC/EH aerosol than in cigarette smoke. Concentrations of particular elements/metals within EC/EH brands were sometimes variable. Aerosols generated at low and high air-flow rates produced the same pattern of elements, although the total element concentration decreased at the higher air flow rate. The relative amount of elements in the first and last 60 puffs was generally different. Silicon was the dominant element in aerosols from all EC/EH brands and in cigarette smoke. The elements appeared to come from the filament (nickel, chromium), thick wire (copper coated with silver), brass clamp (copper, zinc), solder joints (tin, lead), and wick and sheath (silicon, oxygen, calcium, magnesium, aluminum). Lead was identified in the solder and aerosol of two brands of EHs (up to 0.165 µg/10 puffs). CONCLUSION: These data show that EC/EH aerosols contain a mixture of elements, including heavy metals, with concentrations often significantly higher than in conventional cigarette smoke. While the health effects of inhaling mixtures of heated metals is currently not known, these data will be valuable in future risk assessments involving EC/EH elements/metals.
[Mh] Termos MeSH primário: Aerossóis/análise
Compostos Inorgânicos/química
Metais/química
[Mh] Termos MeSH secundário: Cromo/química
Cobre/química
Sistemas Eletrônicos de Liberação de Nicotina/métodos
Eletrônica/métodos
Nebulizadores e Vaporizadores
Níquel/química
Nicotina/química
Prata/química
Fumaça/análise
Espectrometria por Raios X/métodos
Tabaco/anatomia & histologia
Zinco/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Aerosols); 0 (Inorganic Chemicals); 0 (Metals); 0 (Smoke); 0R0008Q3JB (Chromium); 12597-71-6 (brass); 3M4G523W1G (Silver); 6M3C89ZY6R (Nicotine); 789U1901C5 (Copper); 7OV03QG267 (Nickel); J41CSQ7QDS (Zinc)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170418
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0175430


  9 / 1462 MEDLINE  
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[PMID]:28405753
[Au] Autor:Tromboni F; Dodds WK
[Ad] Endereço:Departamento de Ecologia, IBRAG, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil. flavia.tromboni@gmail.com.
[Ti] Título:Relationships Between Land Use and Stream Nutrient Concentrations in a Highly Urbanized Tropical Region of Brazil: Thresholds and Riparian Zones.
[So] Source:Environ Manage;60(1):30-40, 2017 Jul.
[Is] ISSN:1432-1009
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Nutrient enrichment in streams due to land use is increasing globally, reducing water quality and causing eutrophication of downstream fresh and coastal waters. In temperate developed countries, the intensive use of fertilizers in agriculture is a main driver of increasing nutrient concentrations, but high levels and fast rates of urbanization can be a predominant issue in some areas of the developing world. We investigated land use in the highly urbanized tropical State of Rio de Janeiro, Brazil. We collected total nitrogen, total phosphorus, and inorganic nutrient data from 35 independent watersheds distributed across the State and characterized land use at a riparian and entire watershed scales upstream from each sample station, using ArcGIS. We used regression models to explain land use influences on nutrient concentrations and to assess riparian protection relationships to water quality. We found that urban land use was the primary driver of nutrient concentration increases, independent of the scale of analyses and that urban land use was more concentrated in the riparian buffer of streams than in the entire watersheds. We also found significant thresholds that indicated strong increases in nutrient concentrations with modest increases in urbanization reaching maximum nutrient concentrations between 10 and 46% urban cover. These thresholds influenced calculation of reference nutrient concentrations, and ignoring them led to higher estimates of these concentrations. Lack of sewage treatment in concert with urban development in riparian zones apparently leads to the observation that modest increases in urban land use can cause large increases in nutrient concentrations.
[Mh] Termos MeSH primário: Monitoramento Ambiental/métodos
Eutrofização
Rios/química
Urbanização/tendências
Poluentes Químicos da Água/análise
[Mh] Termos MeSH secundário: Agricultura
Brasil
Compostos Inorgânicos/análise
Modelos Teóricos
Nitrogênio/análise
Fósforo/análise
Clima Tropical
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Inorganic Chemicals); 0 (Water Pollutants, Chemical); 27YLU75U4W (Phosphorus); N762921K75 (Nitrogen)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170414
[St] Status:MEDLINE
[do] DOI:10.1007/s00267-017-0858-8


  10 / 1462 MEDLINE  
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[PMID]:28388041
[Au] Autor:Baryshnikov G; Minaev B; Ågren H
[Ad] Endereço:Division of Theoretical Chemistry and Biology, Royal Institute of Technology , SE-106 91 Stockholm, Sweden.
[Ti] Título:Theory and Calculation of the Phosphorescence Phenomenon.
[So] Source:Chem Rev;117(9):6500-6537, 2017 May 10.
[Is] ISSN:1520-6890
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Phosphorescence is a phenomenon of delayed luminescence that corresponds to the radiative decay of the molecular triplet state. As a general property of molecules, phosphorescence represents a cornerstone problem of chemical physics due to the spin prohibition of the underlying triplet-singlet emission and because its analysis embraces a deep knowledge of electronic molecular structure. Phosphorescence is the simplest physical process which provides an example of spin-forbidden transformation with a characteristic spin selectivity and magnetic field dependence, being the model also for more complicated chemical reactions and for spin catalysis applications. The bridging of the spin prohibition in phosphorescence is commonly analyzed by perturbation theory, which considers the intensity borrowing from spin-allowed electronic transitions. In this review, we highlight the basic theoretical principles and computational aspects for the estimation of various phosphorescence parameters, like intensity, radiative rate constant, lifetime, polarization, zero-field splitting, and spin sublevel population. Qualitative aspects of the phosphorescence phenomenon are discussed in terms of concepts like structure-activity relationships, donor-acceptor interactions, vibronic activity, and the role of spin-orbit coupling under charge-transfer perturbations. We illustrate the theory and principles of computational phosphorescence by highlighting studies of classical examples like molecular nitrogen and oxygen, benzene, naphthalene and their azaderivatives, porphyrins, as well as by reviewing current research on systems like electrophosphorescent transition metal complexes, nucleobases, and amino acids. We furthermore discuss modern studies of phosphorescence that cover topics of applied relevance, like the design of novel photofunctional materials for organic light-emitting diodes (OLEDs), photovoltaic cells, chemical sensors, and bioimaging.
[Mh] Termos MeSH primário: Simulação por Computador
Luminescência
[Mh] Termos MeSH secundário: Seres Humanos
Compostos Inorgânicos/química
Medições Luminescentes
Compostos Orgânicos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Inorganic Chemicals); 0 (Organic Chemicals)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170619
[Lr] Data última revisão:
170619
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170408
[St] Status:MEDLINE
[do] DOI:10.1021/acs.chemrev.7b00060



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