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1.
Sci Rep ; 11(1): 3764, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33580110

RESUMO

Two novel types of anion exchange membranes (AEMs) having imidazolium-type functionalised nanofibrous substrates were prepared using the facile and potentially scalable method. The membranes' precursors were prepared by graft copolymerization of vinylbenzyl chloride (VBC) onto syndiotactic polypropylene (syn-PP) and polyamide-66 (PA-66) nanofibrous networks followed by crosslinking with 1,8-octanediamine, thermal treatment and subsequent functionalisation of imidazolium groups. The obtained membranes displayed an ion exchange capacity (IEC) close to 1.9 mmol g-1 and ionic (OH-) conductivity as high as 130 mS cm-1 at 80 °C. This was coupled with a reasonable alkaline stability representing more than 70% of their original conductivity under accelerated degradation test in 1 M KOH at 80 °C for 360 h. The effect of ionomer binder on the performance of the membrane electrode assembly (MEA) in AEM fuel cell was evaluated with the optimum membrane. The MEA showed a power density of as high as 440 mW cm-2 at a current density is 910 mA cm-2 with diamine crosslinked quaternized polysulfone (DAPSF) binder at 80 °C with 90% humidified H2 and O2 gases. Such performance was 2.3 folds higher than the corresponding MEA performance with quaternary ammonium polysulfone (QAPS) binder at the same operating conditions. Overall, the newly developed membrane was found to possess not only an excellent combination of physico-chemical properties and a reasonable stability but also to have a facile preparation procedure and cheap ingredients making it a promising candidate for application in AEM fuel cell.

2.
ACS Appl Mater Interfaces ; 7(31): 17008-15, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26196374

RESUMO

High level of phosphotungstic acid (PWA) was self-immobilized on electrospun nylon nanofiberous sheet to fabricate highly selective methanol barrier layer for sandwich structured proton conducting membranes. Simple tuning for the assembly conditions of central layer and thickness of outer Nafion layers allowed obtaining different composite membranes with superior methanol barrier properties (namely, P=3.59×10(-8) cm2 s(-1)) coupled with proton conductivities reaching 58.6 mS cm(-1) at 30 °C. Comparable activation energy for proton transport and more than 20 times higher selectivity than Nafion 115 confirm the effectiveness of the central layer and resulting membranes for application in direct methanol fuel cells (DMFCs). When tested in DMFC single cell, the performance of hybrid membrane was far better than Nafion 115 especially at higher methanol concentrations.

3.
Iran J Public Health ; 44(3): 388-95, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25905083

RESUMO

Iran has been active in human nutrition training for the past five decades, but the existing curricular programs do not equip the graduates with the knowledge and skills required for solving food security and nutritional problems of the country. Given this, the Nutrition Department (ND) of Iran's Ministry of Health and Medical Education (MOHME) initiated a curricular reform to develop responsive graduate programs in key areas of nutrition that fill the existing gaps in nutrition training with the goal of improving nutrition policy-making and program development, implementation and evaluation. ND called for a request for proposals for a project entitled "Graduate Level Training in Nutrition". Specifically, with technical assistance from leading academic institutions in Asia, North America and UK, seven new graduate programs were housed in three separate institutions, but coordinated so that together they form a broad multidisciplinary resource for graduate education and research. These seven-degree programs are MSc and PhD in Molecular/Cellular Nutrition, MSc and PhD in Nutritional Epidemiology, MSc and PhD in Food Policy and Nutrition Intervention, and MSc in Community Nutrition. The programs were prepared in collaboration and active participation of selected faculty members of the three Iranian universities, International Union of Nutritional Sciences and the University of Philippines at Los Baños. The development of these programs was made possible through a loan from the World Bank, under the Second Primary Health and Nutrition Project in the MOHME.

6.
Public Health Nutr ; 5(1A): 149-55, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12027278

RESUMO

OBJECTIVE: To describe the emergence of the nutrition transition, and associated morbidity shifts, in the Islamic Republic of Iran. DESIGN: Review and analysis of secondary data relating to the socio-political and nutritional context, demographic trends, food utilisation and consumption patterns, obesity, and diet-related morbidity. RESULTS AND CONCLUSIONS: The nutrition transition in Iran is occurring rapidly, secondary to the rapid change in fertility and mortality patterns and to urbanisation. The transition is occurring against the backdrop of lack of sustained economic growth. There is considerable imbalance in food consumption with low nutrient density characterising diets at all income levels, over-consumption evident among more than a third of households, and food insecurity among 20% of the population. Obesity is an emerging problem, particularly in urban areas and for women, and both diabetes and other risk factors for heart disease are becoming significant problems.


Assuntos
Doenças Cardiovasculares/epidemiologia , Abastecimento de Alimentos/estatística & dados numéricos , Transição Epidemiológica , Obesidade/epidemiologia , Mudança Social , Adolescente , Adulto , Idoso , Doenças Cardiovasculares/etiologia , Feminino , Bócio Endêmico/epidemiologia , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Política Nutricional , Fenômenos Fisiológicos da Nutrição , Obesidade/complicações , Fatores Sexuais , Fatores Socioeconômicos , Urbanização
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