Nowadays,many research works are carried for all grades of concrete to make the concrete most economical and durable there by adding the supplementary cementitious materials and alternative replacement aggregates.In t...Nowadays,many research works are carried for all grades of concrete to make the concrete most economical and durable there by adding the supplementary cementitious materials and alternative replacement aggregates.In this research work deals with the experimental investigation of mechanical properties of the M30,M50 and M80 grade concrete by replacing the fine and coarse aggregate by foundry sand and crushed concrete waste respectively.Mix design procedures were followed as per IRC44:2017 guidelines and recommendation.Proper dosage of super plasticizer(SP)was maintained in the concrete to make it better performed.In this present investigation,a Poly Propylene fibre(PPF)of 0.3%by weight of the cement is used.Mechanical properties such as Compressive strength and Flexural Strength were determined by preparing the respective mould sizes for specific test and are cured for 7,14 and 28 days and result obtained for respective days were tabulated and discussed.展开更多
Biomaterials have attracted more attention from biomedical research in recent years. Yet there are still unmet demands for current biomaterials, such as the reduction of local inflammation of the implantation site. Po...Biomaterials have attracted more attention from biomedical research in recent years. Yet there are still unmet demands for current biomaterials, such as the reduction of local inflammation of the implantation site. Poly-Propylene Carbonate （PPC）, a polymer with ester bonds on COz backbone, degrades to CO2 and water, which are natural components of human body, yielding less inflammatory response than traditional biomaterials. However, the tensile strength and heat resistance properties of PPC are less ideal. In order to improve the properties of PPC, we have developed a new PPC （M-PPC）, modified by mixing with Poly-3-Hydroxybutyrate （PHB）. Here, we report the biodistribution profiles of PPC and M-PPC, their biocompatibility and toxicity. 125I-radiolabeled PPC and M-PPC were prepared and their biodistribution in Balb/c mice were investigated. Then acute systemic toxicity and haemolysis assays were conducted to study their toxicity and biocompatibility respectively. Results show that M-PPC has a good potential to be used as bone repair materials because it possesses typical biodistribution pattern in major organs, minimal toxicity and good biocompatibility.展开更多
A novel phenolic rigid organic filler （named KD） with a high melting point was dispersed in an isotactic polypropylene （iPP） matrix by solution-mixing and/or melt-mixing. A series of KD/iPP blends was prepared wit...A novel phenolic rigid organic filler （named KD） with a high melting point was dispersed in an isotactic polypropylene （iPP） matrix by solution-mixing and/or melt-mixing. A series of KD/iPP blends was prepared with or without addition of maleic anhydride-grafted polypro- pylene （MAPP） as a compatibilizer. Influences of MAPP and mixing methods on the filler dispersion were studied using polaried optical microscope （POM）, scanning electron microscope （SEM） and tensile test. The filler particles are always inclined to form large irregular aggregates in the iPP matrix due to their significant differences in polarity and solubility in solvent. However, an iPP/MAPP/KD （PMK） blend containing filler particles with a quasi-spherical shape （-97.8 nm in diameter） and narrow particle size distribution （polydispersity index = 1.076） was successfully prepared by incorporating MAPP to reduce the interfacial tension and surface free energy between the dispersion phase and the continuous phase, and adopting a spray-drying method after solution-mixing to suppress the increase of the size of the dispersed phase during the removal of solvent.展开更多
文摘Nowadays,many research works are carried for all grades of concrete to make the concrete most economical and durable there by adding the supplementary cementitious materials and alternative replacement aggregates.In this research work deals with the experimental investigation of mechanical properties of the M30,M50 and M80 grade concrete by replacing the fine and coarse aggregate by foundry sand and crushed concrete waste respectively.Mix design procedures were followed as per IRC44:2017 guidelines and recommendation.Proper dosage of super plasticizer(SP)was maintained in the concrete to make it better performed.In this present investigation,a Poly Propylene fibre(PPF)of 0.3%by weight of the cement is used.Mechanical properties such as Compressive strength and Flexural Strength were determined by preparing the respective mould sizes for specific test and are cured for 7,14 and 28 days and result obtained for respective days were tabulated and discussed.
文摘Biomaterials have attracted more attention from biomedical research in recent years. Yet there are still unmet demands for current biomaterials, such as the reduction of local inflammation of the implantation site. Poly-Propylene Carbonate （PPC）, a polymer with ester bonds on COz backbone, degrades to CO2 and water, which are natural components of human body, yielding less inflammatory response than traditional biomaterials. However, the tensile strength and heat resistance properties of PPC are less ideal. In order to improve the properties of PPC, we have developed a new PPC （M-PPC）, modified by mixing with Poly-3-Hydroxybutyrate （PHB）. Here, we report the biodistribution profiles of PPC and M-PPC, their biocompatibility and toxicity. 125I-radiolabeled PPC and M-PPC were prepared and their biodistribution in Balb/c mice were investigated. Then acute systemic toxicity and haemolysis assays were conducted to study their toxicity and biocompatibility respectively. Results show that M-PPC has a good potential to be used as bone repair materials because it possesses typical biodistribution pattern in major organs, minimal toxicity and good biocompatibility.
文摘A novel phenolic rigid organic filler （named KD） with a high melting point was dispersed in an isotactic polypropylene （iPP） matrix by solution-mixing and/or melt-mixing. A series of KD/iPP blends was prepared with or without addition of maleic anhydride-grafted polypro- pylene （MAPP） as a compatibilizer. Influences of MAPP and mixing methods on the filler dispersion were studied using polaried optical microscope （POM）, scanning electron microscope （SEM） and tensile test. The filler particles are always inclined to form large irregular aggregates in the iPP matrix due to their significant differences in polarity and solubility in solvent. However, an iPP/MAPP/KD （PMK） blend containing filler particles with a quasi-spherical shape （-97.8 nm in diameter） and narrow particle size distribution （polydispersity index = 1.076） was successfully prepared by incorporating MAPP to reduce the interfacial tension and surface free energy between the dispersion phase and the continuous phase, and adopting a spray-drying method after solution-mixing to suppress the increase of the size of the dispersed phase during the removal of solvent.
