This paper traces the origins and achievements of the R^seau Ouest et Centre Africain du Riz--ROCARIZ （West and Central Africa Rice Research and Development Network）. The ROCARIZ institutional arrangement showed tha...This paper traces the origins and achievements of the R^seau Ouest et Centre Africain du Riz--ROCARIZ （West and Central Africa Rice Research and Development Network）. The ROCARIZ institutional arrangement showed that rice science is approached from multi-stakeholder perspectives that place end users and entrepreneurs at the center of research for development, and collaboration among rice-based stakeholders can be enhanced and sustained. The ROCARIZ used competitive research grants through multi-stakeholder task forces to generate, adapt, and facilitate the adoption of rice-based technologies and approaches by resource poor households. The grants contributed to： （1） farmer adoption of high yielding and multiple stress resilient lowland NERICAs （New Rices for Africa） （NERICA-L）; （2） producer access to credit and services resulting in increased marketing of quality seed rice, paddy, and grain rice by farmer entrepreneurs and poor rural households; （3） improved skills of stakeholders on the use of impact assessment tools to demonstrate adoption of rice-based technologies; （4） enhanced skills of rice breeders in molecular assisted marker selection to shorten the varietal development process; and （S） experiential learning and sharing to improve access to information and knowledge.展开更多
Many researchers have investigated the use of recycled tire products in several traditional civil engineering materials. This research is exploring the use of steel cords, a by-product of the tire recycling process, i...Many researchers have investigated the use of recycled tire products in several traditional civil engineering materials. This research is exploring the use of steel cords, a by-product of the tire recycling process, in concrete mixes. Different concrete specimens were fabricated and tested in uniaxial compression and splitting tensile strength. The steel cords were substituted into the concrete mix in volumetric percentages of various ratios. Results show that mechanical properties of concrete made with steel cords are improved compared with concrete mix made with the traditional scrap-tires recycled material. Also, results show that even though the compressive strength is reduced when using steel cords, this reduction is minimal. When 2% of steel cords are used there is 18% increase in ductility. Moreover, splitting tensile tests show that concrete mixtures with any steel cords content have much greater toughness than control mixture. This mechanical property mix indicates an excellent potential application of modified concrete mix in structures that absorb large amount of energy.展开更多
文摘This paper traces the origins and achievements of the R^seau Ouest et Centre Africain du Riz--ROCARIZ （West and Central Africa Rice Research and Development Network）. The ROCARIZ institutional arrangement showed that rice science is approached from multi-stakeholder perspectives that place end users and entrepreneurs at the center of research for development, and collaboration among rice-based stakeholders can be enhanced and sustained. The ROCARIZ used competitive research grants through multi-stakeholder task forces to generate, adapt, and facilitate the adoption of rice-based technologies and approaches by resource poor households. The grants contributed to： （1） farmer adoption of high yielding and multiple stress resilient lowland NERICAs （New Rices for Africa） （NERICA-L）; （2） producer access to credit and services resulting in increased marketing of quality seed rice, paddy, and grain rice by farmer entrepreneurs and poor rural households; （3） improved skills of stakeholders on the use of impact assessment tools to demonstrate adoption of rice-based technologies; （4） enhanced skills of rice breeders in molecular assisted marker selection to shorten the varietal development process; and （S） experiential learning and sharing to improve access to information and knowledge.
文摘Many researchers have investigated the use of recycled tire products in several traditional civil engineering materials. This research is exploring the use of steel cords, a by-product of the tire recycling process, in concrete mixes. Different concrete specimens were fabricated and tested in uniaxial compression and splitting tensile strength. The steel cords were substituted into the concrete mix in volumetric percentages of various ratios. Results show that mechanical properties of concrete made with steel cords are improved compared with concrete mix made with the traditional scrap-tires recycled material. Also, results show that even though the compressive strength is reduced when using steel cords, this reduction is minimal. When 2% of steel cords are used there is 18% increase in ductility. Moreover, splitting tensile tests show that concrete mixtures with any steel cords content have much greater toughness than control mixture. This mechanical property mix indicates an excellent potential application of modified concrete mix in structures that absorb large amount of energy.
