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1.
Chem Mater ; 36(2): 803-814, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38282686

RESUMO

To improve the energy density of LiFePO4 (LFP) cathode materials for Li-ion cells, we have utilized a modified mechanofusion method for preparing micrometer-sized LFP/C composite flake particles. The resulting flake particle morphology resulted in improved packing efficiency, enabling an electrode porosity of 14% to be achieved at high loadings, which represents a volumetric energy density increase of 28% compared to conventional LFP. Furthermore, LFP/C flake composites electrodes were found to have a higher coulombic efficiency, a reduced voltage-polarization, and a greatly reduced charge transfer resistance compared to conventional LFP electrodes. This is believed to be due to the low surface area of the LFP/C flake composite particles coupled to fast Li+ ion grain boundary diffusion. The ability to make highly dense LFP and low surface area electrodes could have profound impacts, allowing for Li-ion cells to be made with low cost and low environmental impact LFP, while high achieving volumetric energy densities and high coulombic efficiencies.

2.
Chem Rev ; 115(4): 2043, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25651035
3.
Chem Rev ; 114(23): 11444-502, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25399614
4.
Int J Tuberc Lung Dis ; 23(12): 1283-1285, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31931912

RESUMO

The zoonotic potential of Mycobacterium tuberculosis complex species is well known. However, M. pinnipedii, the causative agent of tuberculosis (TB) predominantly in seals and sea lions, has never been isolated from a respiratory specimen in humans. Here we describe the first known human case of pulmonary TB caused by M. pinnipedii in a 79-year-old female patient with rheumatoid arthritis and chronic respiratory disease. The epidemiological data did not explain where the patient was exposed to M. pinnipedii, thus leaving the source of transmission unknown.


Assuntos
Artrite Reumatoide , Mycobacterium/isolamento & purificação , Doença Pulmonar Obstrutiva Crônica , Tuberculose Pulmonar/diagnóstico , Idoso , Animais , Caniformia/microbiologia , Croácia , Diagnóstico Diferencial , Evolução Fatal , Feminino , Humanos , Tuberculose Pulmonar/diagnóstico por imagem , Tuberculose Pulmonar/microbiologia , Zoonoses/diagnóstico , Zoonoses/microbiologia
5.
ACS Appl Mater Interfaces ; 10(44): 38246-38254, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30360107

RESUMO

NaNi0.5Mn0.5O2 is a promising sodium-ion battery cathode material that has been extensively studied. However, the air sensitivity of this material limits practical application and is not well understood. Here, we present a detailed study of NaNi0.5Mn0.5O2 powders stored in different atmospheres (oxygen, argon, and carbon dioxide), either dry or wet. X-ray diffraction and Fourier transform infrared measurements were used to characterize the materials and their surface species before and after controlled-atmosphere storage. It was determined that the exposure of untreated NaNi0.5Mn0.5O2 powders to moisture results in desodiation and material degradation, leading to poor cycling. This effect was found to be caused by reactive surface species. From these results, a simple ethanol washing method was found to significantly reduce the air-reactivity and improve the electrochemical performance of NaNi0.5Mn0.5O2 by removing surface impurities formed by air exposure.

6.
ACS Appl Mater Interfaces ; 10(26): 22013-22022, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29897233

RESUMO

The synthesis, structure, and electrochemistry in Na cells of NaFe xM1- xO2 positive electrode materials with M = Ni, Co0.5Ni0.5, and Co are reported. In particular, the properties of O3-NaFeO2-NaCo0.5Ni0.5O2 solid solutions having compositions NaFe x(Co0.5Ni0.5)1- xO2 with 0 ≤ x ≤ 0.5 are explored. It is found that the substitution of Fe in NaNi0.5Co0.5O2 causes an increase in first cycle energy density from 320 to 440 mWh/g in a 1.5-4.0 V test. However, capacity retention is generally reduced when x is increased for all M = Ni, Co0.5Ni0.5, and Co. In general, NaFe xM1- xO2 samples with M = Co had the highest capacity retention for all values of x. Ex situ X-ray diffraction and Mössbauer results of as-prepared and charged materials are directly compared for NaFe x(Co0.5Ni0.5)1- xO2 and NaFe xCo1- xO2 ( x = 0.4, 0.5). Iron was found to be in the +3 oxidation state in the as-prepared materials. A significant fraction of Fe3+ is oxidized to Fe4+ in these samples when they are charged to 4.0 V.

7.
Int J Tuberc Lung Dis ; 11(6): 652-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17519097

RESUMO

SETTING: This paper describes an outbreak of human and related bovine tuberculosis (TB) caused by Mycobacterium caprae in Croatia. A 13-year-old boy clinically presented enlargement of cervical lymph node with consecutive isolation of M. caprae. His 7-year-old sister, who had no clinical signs of disease, hyper-reacted to the purified protein derivative (PPD) test (>25 mm) and peribronchial infiltration was found by radiology. The children came from a family that ran a small-sized cattle dairy farm. DESIGN: All cattle on the farm were subjected to cutaneous TB testing: six of the 14 reacted positive, while three were suspicious. The entire herd was slaughtered, their carcasses examined and collected material subjected to pertinent diagnostic procedures. RESULTS: Gross examination findings consistent with TB were observed in the PPD-positive cows. Mycobacteria isolated from the boy and cattle were identified by classical and molecular methods, confirming M. caprae as the causative agent. CONCLUSION: Although not bacteriologically proven, consumption of raw milk or non-pasteurised milk products from infected dairy cattle was suspected as the source of infection in humans. Our findings confirm the domination of M. caprae among cattle in Croatia and represent the first evidence of M. caprae infection in humans in Croatia.


Assuntos
DNA Bacteriano/análise , Indústria de Laticínios , Mycobacterium bovis/isolamento & purificação , Tuberculose Bovina/diagnóstico , Tuberculose/diagnóstico , Zoonoses , Adolescente , Adulto , Animais , Antituberculosos/uso terapêutico , Técnicas de Tipagem Bacteriana/veterinária , Bovinos , Croácia , Feminino , Humanos , Masculino , Leite/microbiologia , Mycobacterium bovis/classificação , Mycobacterium bovis/genética , Resultado do Tratamento , Teste Tuberculínico/veterinária , Tuberculose/tratamento farmacológico , Tuberculose/genética , Tuberculose/microbiologia , Tuberculose/transmissão , Tuberculose Bovina/genética , Tuberculose Bovina/patologia , Tuberculose Bovina/transmissão
8.
Int J Tuberc Lung Dis ; 20(7): 934-40, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27287647

RESUMO

SETTING: The value of microbiological criteria in diagnosing non-tuberculous mycobacteria pulmonary disease (NTM-PD) and monitoring its epidemiology is unknown. OBJECTIVES: To correlate the rate of NTM-PD based on microbiological criteria (American Thoracic Society/Infectious Diseases Society of America [ATS/IDSA] or stricter microbiological criteria) compared with the full ATS/IDSA criteria, to assess the positive predictive value (PPV) of different microbiological criteria in predicting NTM-PD, and to evaluate the clinical relevance of different NTM species. DESIGN: Retrospective study of all patients with pulmonary NTM isolates in Croatia during an 8-year period. NTM species were divided into low, intermediate and high clinical relevance groups for additional analyses. RESULTS: Good correlation between both microbiological and full ATS/IDSA criteria was observed. The PPV of stricter and ATS/IDSA microbiological criteria was respectively 93.3% and 59.8%. The usefulness of microbiological criteria varied between groups. ATS/IDSA microbiological criteria had a PPV of 89.8% in the high relevance group, while in the intermediate relevance group, the PPV of stricter and ATS/IDSA microbiological criteria was respectively 94.3% and 63.4%. CONCLUSIONS: Microbiological criteria are useful in detecting NTM-PD, allowing laboratory-based monitoring. Stricter criteria should be used for species of low clinical relevance, and less stringent criteria for species of high relevance in the local setting.


Assuntos
Técnicas Bacteriológicas , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/isolamento & purificação , Infecções Respiratórias/microbiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Croácia/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Micobactérias não Tuberculosas/classificação , Valor Preditivo dos Testes , Prevalência , Reprodutibilidade dos Testes , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Estudos Retrospectivos , Adulto Jovem
9.
Int J Tuberc Lung Dis ; 17(6): 836-41, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23676172

RESUMO

SETTING: The clinical relevance of non-tuberculous mycobacteria (NTM) in Croatia is unknown. OBJECTIVE: To estimate the isolation rate of NTM, record geographical differences and assess the burden of pulmonary NTM disease in Croatia. DESIGN: Nationwide retrospective cohort study of all Croatian residents with NTM isolated by culture in the period from 2006 to 2010. Microbiological criteria of the American Thoracic Society were used to establish a laboratory-based case definition of possible and probable NTM disease. RESULTS: Of 1187 individuals with pulmonary NTM isolates, 8.6% met the possible and 5.5% met the probable disease criteria. We estimated an annual incidence of probable pulmonary NTM disease of 0.23 per 100,000 population. This estimated annual incidence was 0.35/100,000 in the coastal region and 0.17/100,000 in the continental region. Species distribution differed between coastal and continental Croatia. NTM isolation frequency increased over the study period. CONCLUSION: Geography plays an important role in NTM species distribution and possible disease. The overall burden of NTM pulmonary disease in Croatia is still low compared to that of tuberculosis, but it is higher in the coastal region compared to the continental region.


Assuntos
Pneumopatias/epidemiologia , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Micobactérias não Tuberculosas/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos de Coortes , Croácia/epidemiologia , Feminino , Humanos , Incidência , Lactente , Pneumopatias/microbiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
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