18 research outputs found
An assay of some thermal characteristics, chemical and phytochemical constituents of Hymenocarida acida timber
Timber has always played an influencing role in human lives. The quality of timber and its behavior in response to fire depends on many parameters. As a result Hymenocardiaacidawood was studied in terms of thermal, chemical, physical and variable techniques. The results obtained were as follows: afterglow time 58.33sec, flame duration 271.67sec, flame propagation rate 4.4x10-2cm.s-1, ignition time 3.67sec, thermal conductivity14.37 x 102Umoh/cm, electrical conductivity 4.4x10-3Sm-1, ash content 0.95%, moisture content 12.67%, oven dry density 78.7x10-2g.cm-3, water imbibitions (at different time intervals: 30mins 11.1%, 5hrs 13.8% and 24hrs 22.3%), etc, These results showed it to be a good timber suitable for various construction purposes. Phytochemical screening showed the presence of saponins, tannins, steroids, flavonoids, carbohydrates, proteins, resins, terpenoids, glycosides and alkaloids. The Atomic Absorption Spectrophotometer (AAS) of the sample showed the presence of some metals such as Na, K, Pb, Ca, As, Zn, Mg, and Cu in the decreasing order of their concentrations. The thin layer chromatographic analysis of the chloroform and chloroform-methanol extracts which gave three spots with Rf values of 0.7, 0.6 and 0.5 was further characterized using Fourier Transform Infrared and Ultraviolet Spectroscopic methods. The Fourier Transform Infrared and Ultraviolet spectra suggested a 1, 2, 3- trisubstitutedphenylamide with OH, CO and CN groups attached as the functional groups present. The chemical components analysis showed the presence of cellulose, hemicelluloses, lignin and other constituents in their right proportion. The results provided the required information on the properties of Hymenocardiaacidawood. It also confirmed the efficiency of the wood for various construction purposes and its medicinal ability due to the presence of the secondary metabolites.Keywords: Timber, Hymenocardia acida, Functional group analysis, Phytochemical, thermal andchemical constituent
Reinforcement of polypropylene with natural fibers : mitigation of environmental pollution
DATA AVAILABILITY : Data will be made available on request.Recently, natural fibers have gained research attention in reinforcing polymers due to their availability and unique properties in polymer applications. Preliminary studies indicate indiscriminate disposal of human hair (HH) and the burning of cow hair (CH) and sheep hair (SH) by abattoir operators in Nigeria; this has become a source of concern owing to the hazardous nature of these activities to human health and the environment. This study is, therefore, essential and seeks to utilize these waste materials in an environmentally sustainable way, as the hair fibers used in this work are renewable and will enhance the economy of any country if adequately utilized. The composites of Polypropylene (PP), human, sheep, and cow tail hair fibers were prepared at different weight percentage concentrations of 0, 2, 4, 6, and 8 w% using an injection molding machine. Untreated and treated PP composites were analyzed for average diameter, length, and density; the composites were also characterized for ultimate tensile strength, flexural strength, hardness, and impact strength. The average diameter assessment indicates viz: Cow tail hair > Human hair > Sheep hair. The sequence for hair fiber lengths shows that Sheep hair > Human hair > Cow hair, and the order for average density is Cow tail hair > Human hair > Sheep hair. The analysis of the mechanical properties of the reinforced and unreinforced PP composite showed that the Human hair/PP composite gave the best enhancement for ultimate tensile strength and modulus, flexural strength, and modulus at 8% fiber loading. Cow tail hair/PP composite yielded the best elongation at break at 2% fiber loading. Human hair/PP composite showed the best yield for impact strength at 4% fiber loading, while the Cow tail hair composite performed best for the hardness test at 2% fiber loading. The surface scanning electronic microscope (SEM) images showed no significant manufacturing defect on composites except for the air entrapment in the image of cow tail hair. The study also observed that there is no fiber breakage or void observed in the images. SEM images of the PP-composites interface at 8% maximum loading showed reasonably good fiber adhesion to the polymer matrix. This study is recommended for environmental sustainability and to improve material properties for various applications.http://www.elsevier.com/locate/envcam202
Immunochemical estimation of some proteins in Nigerian paired maternal and fetal blood.
The immune response in an individual is relevant to his survival, and this is especially true of people living in Africa where they are constantly challenged by a host of parasitic antigens. The antibodies which result from such immune response are found in the immunoglobulins: IgA, IgG, IgM, and IgD. Thus the concentration of these immune substances in the circulation provides some useful index of the immune state of the individual. Within the past 2 years immunochemical estima-tion of immunoglobulins at this institution and at a few other centres in parts of Africa has been concerned with immunoglobulin in the Africa
Angiotensin II and breast cancer
EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Reinforcement of polypropylene with natural fibers: Mitigation of environmental pollution
ABSTRACT: Recently, natural fibers have gained research attention in reinforcing polymers due to their availability and unique properties in polymer applications. Preliminary studies indicate indiscriminate disposal of human hair (HH) and the burning of cow hair (CH) and sheep hair (SH) by abattoir operators in Nigeria; this has become a source of concern owing to the hazardous nature of these activities to human health and the environment. This study is, therefore, essential and seeks to utilize these waste materials in an environmentally sustainable way, as the hair fibers used in this work are renewable and will enhance the economy of any country if adequately utilized. The composites of Polypropylene (PP), human, sheep, and cow tail hair fibers were prepared at different weight percentage concentrations of 0, 2, 4, 6, and 8 w% using an injection molding machine. Untreated and treated PP composites were analyzed for average diameter, length, and density; the composites were also characterized for ultimate tensile strength, flexural strength, hardness, and impact strength. The average diameter assessment indicates viz: Cow tail hair > Human hair > Sheep hair. The sequence for hair fiber lengths shows that Sheep hair > Human hair > Cow hair, and the order for average density is Cow tail hair > Human hair >Sheep hair. The analysis of the mechanical properties of the reinforced and unreinforced PP composite showed that the Human hair/PP composite gave the best enhancement for ultimate tensile strength and modulus, flexural strength, and modulus at 8% fiber loading. Cow tail hair/PP composite yielded the best elongation at break at 2% fiber loading. Human hair/PP composite showed the best yield for impact strength at 4% fiber loading, while the Cow tail hair composite performed best for the hardness test at 2% fiber loading. The surface scanning electronic microscope (SEM) images showed no significant manufacturing defect on composites except for the air entrapment in the image of cow tail hair. The study also observed that there is no fiber breakage or void observed in the images. SEM images of the PP-composites interface at 8% maximum loading showed reasonably good fiber adhesion to the polymer matrix. This study is recommended for environmental sustainability and to improve material properties for various applications