The present work deals on one hand with the valorization of wastes plastics, polyethylene terephthalate (PET) and Canarium schweinfurthii (CS) for the preparation of polyethylene terephthalate activated carbon (PETAC)...The present work deals on one hand with the valorization of wastes plastics, polyethylene terephthalate (PET) and Canarium schweinfurthii (CS) for the preparation of polyethylene terephthalate activated carbon (PETAC) and Canarium schweinfurthii/polyethylene terephthalate activated carbon (CS/PETAC). These adsorbents, on the other hand, were used for removal Rhodamine B (RhB) in an aqueous solution. PET and CS precursors were subjected to thermogravimetric analysis (TGA) and differential scanning colorimetry (DSC). Meanwhile PETAC and CS/PETAC were characterized using scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), X-ray fluorescence (XRF), Fourier transformed infrared spectroscopy (FT-IR) and nitrogen adsorption/desorption (N<sub>2</sub>-BET). The N<sub>2</sub>-BET results revealed an increase of the specific surface area from 6.75 m<sup>2</sup>/g to 1282.0 m<sup>2</sup>/g for PETAC and CS/PETAC. The results of characterization indicated the key role played by plastic wastes to enhance the structural and functional properties of CS/PETAC. The RhB removal from the aqueous solution onto PETAC and CS/PETAC was found to be independent of pH, with an optimal contact time of RhB removal within 10 min for materials. The non-linear adsorption isotherm data for the adsorption process showed that the Langmuir and Freundlich models best fitted the RhB adsorption onto PETAC meanwhile only the Freundlich adsorption isotherm gave the best fit for CS/PETAC according to the correlation coefficient value closed to unity. The pseudo-first and pseudo-second-order kinetic models best described the RhB dye removal on both adsorbents. Additionally, the Elovich model confirmed that chemisorption was the main mechanism followed. These findings proved that CS seeds and PET wastes are low-cost precursors that should be given an added value by transforming them into an outstanding carbon material for dye removal in liquid effluent.展开更多
Objective:To evaluate the anti-infectious and antioxidant activities of hydroethanolic extract of Canarium schweinfurthii on broiler chickens infected by Salmonella enterica serovar Typhimurium,known to be threatening...Objective:To evaluate the anti-infectious and antioxidant activities of hydroethanolic extract of Canarium schweinfurthii on broiler chickens infected by Salmonella enterica serovar Typhimurium,known to be threatening public health.Methods:Animals were divided into six groups of eight animals per group:the normal control group,negative control group,positive control group and three test groups receiving the plant extract at 5,19 and 75 mg/kg bw,respecively.The evolution of the disease as well as the effectiveness of the treatment were monitored by stool culture from the second day post infection until the end of the treatment.In addition,the effects of treatment on growth performances and feed conversion efficiency of broilers were evaluated.For the assessment of antioxidant status,enzymatic and non-enzymatic biomarkers such as catalase,glutathione peroxidase,malondialdehyde and nitric oxide were evaluated in the serum and tissues of animals.Results:The infected chickens treated with oxytetracycline recovered on day 7 after treatment,while animals treated with 19 and 75 mg/kg of Canarium schweinfurthii extract recovered on day 9 and those with 5 mg/kg of the extract on day 10.Salmonella infection caused a decrease on catalase and glutathione peroxidase activities;the administration of various doses of Canarium schweinfurthii extract increased these enzymatic activities.Animals receiving the extract at 5 mg/kg showed a significant increase in catalase activity in serum,heart and lungs while all concentrations of the extract significantly increased glutathione peroxidase activity in the serum,liver and spleen.Concerning non-enzymatic biomarkers,Salmonella infection caused a significant increase of nitric oxide and malondialdehyde concentration in the liver and lungs.Treatment with 75 mg/kg of the extract significantly reduced nitric oxide concentration in the heart and lungs while each dose of the extract reduced and normalized the malondialdehyde level in the serum.Additionally,malondialdehyde production was significantly decreased in the liver,heart and lungs after administration of Canarium schweinfurthii extract at all doses.Conclusions:The hydroethanolic extract of Canarium schweinfurthii attenuates oxidative stress,and is effective in the treatment of avian salmonellosis.展开更多
The aim of this work was to develop and characterize a polyester matrix composite material based on Canarium schweinfurthii Engl core granule. The particle size and the mass fractions of these cores used as fillers in...The aim of this work was to develop and characterize a polyester matrix composite material based on Canarium schweinfurthii Engl core granule. The particle size and the mass fractions of these cores used as fillers in this composite were the two optimization parameters. The experimentation of the twelve sample areas was based on the following optimization parameters: Three particles sizes of 80 1 2 3 ·m-3, which allows us to admit that this composite belongs to the family of light materials. The maximum compressive stress at break was obtained for the formulation 40% filler of size T3. This compressive stress at maximum rupture is in the range of 199.14 MPa. From 0% to 45% of filler, the flexural Young’s modulus of the composite increases whatever the particle size. The highest value is obtained for T2 particle size, i.e. 13.11 GPa. The static friction coefficient of the composite on wood increases as the filler content varies from 0.30 to 0.42. Thus, in view of the properties obtained, this composite can be used as alternative solutions in industrial applications, for the manufacturing of shoe heel, house ceiling, floors for housing and table support.展开更多
The purpose of this study is to determine the morphological, microstructural characteristics and water diffusion parameters of the Canarium schweinfurthii (CS) shellnut. This work is part of a vast project to valorize...The purpose of this study is to determine the morphological, microstructural characteristics and water diffusion parameters of the Canarium schweinfurthii (CS) shellnut. This work is part of a vast project to valorize the above-mentioned cores for possible industrial use as charges in composites or abrasives materials. The study was based on the characterization of intrinsic physical characteristics of the coreshells scanning electron microscopic (SEM) observations desorption, adsorption and absorption kinetics. The water diffusion phenomenon was modeled and it appears that the Page model well predicted the kinetic of drying, absorption and adsorption. The effective diffusion coefficient and the energy of activation were calculated at three isothermal temperatures (50<span style="white-space:nowrap;">°</span>C, 70<span style="white-space:nowrap;">°</span>C and 90<span style="white-space:nowrap;">°</span>C). There was a tendency for hysteresis in the sorption-desorption cycles. These results strongly predicted the possibility of using these products as a filler in composites, clay building materials and cement because of their high water diffusion stability on a macroscopic scale.展开更多
Two forms of A. halimus shrubs: erect habit (A. halimus) and bushy habit shrub (A. schweinfurthii) are used naturally isolated by a considerable distance from each other and occupy the same area. To explore the effect...Two forms of A. halimus shrubs: erect habit (A. halimus) and bushy habit shrub (A. schweinfurthii) are used naturally isolated by a considerable distance from each other and occupy the same area. To explore the effect of natural isolation on the genetic basis of the two forms, Start Codon Targeted (SCoT) and the phylogenetic relationships of A. halimus by sequencing ITS1-5.8S-ITS2 regions of the ribosomal DNA are used. Significant isolation-by-distance relationship was found (r = 0.62, P = 0.001). Soil factors did not influence molecular variations. The natural isolation of A. halimus habitats restricts gene flow among the populations and the observed high within-population genetic diversity (74.19%) in this species is best explained by its outcrossing behaviour, long-lived individuals and overlapping generations. The UPGMA analysis of the SCoT results showed that all the studied populations were divided into two discrete genetic groups with significant separation of the two forms in Burg El-Arab area (Populations 1 and 2) and insignificant separation between two forms in El-Hammam area (population 5 and 6). The sequencing of the ITS1-5.8S-ITS2 rDNA regions also showed the insignificant separation of the two A. halimus forms. We conclude that gene flow depending on habitat fragmentation was the main factor affecting the population genetic differentiation. We suggest that the two forms do not merit specific rank in presence of interference between the two forms and absence of a breeding barrier fail to separate the different populations when they become sympatric.展开更多
Equilibrium moisture contents (EMC) of wood species are very necessary in the utilization of these in service. This study investigated the EMC of five lesser utilized species of Ghana and compared it with that of thre...Equilibrium moisture contents (EMC) of wood species are very necessary in the utilization of these in service. This study investigated the EMC of five lesser utilized species of Ghana and compared it with that of three European species. Sixteen randomly sampled specimens of each of the eight species (heartwood and sapwood) with dimensions 3 cm × 3 cm × 3 cm were exposed at various relative humidity conditions of 30%, 45%, 60%, 75% and 90% in a temperature and humidity-controlled climate chamber at a temperature of 25°C in accordance to German standard DIN 52182. The species are Albies alba, Fagus sylvatica and Picea abies which are European species and Amphimas pterocarpoides, Antiaris toxicaria, Canarium schweinfurthii, Celtis zenkeri and Cola gigantea are wood species from Ghana. Internal wood temperature and humidity were measured with datalogger. Samples were considered to have reached equilibrium at any given humidity when the daily weight changes were less than 0.1 mg according to German standard DIN 52183. After the last measurements of the weight changes, the samples were dried at 103°C until there was a constant weight. The five tropical hardwoods had low sorption values recorded and high sorption values for the European species and this could be attributed to differences in the microstructure of these woods.展开更多
文摘The present work deals on one hand with the valorization of wastes plastics, polyethylene terephthalate (PET) and Canarium schweinfurthii (CS) for the preparation of polyethylene terephthalate activated carbon (PETAC) and Canarium schweinfurthii/polyethylene terephthalate activated carbon (CS/PETAC). These adsorbents, on the other hand, were used for removal Rhodamine B (RhB) in an aqueous solution. PET and CS precursors were subjected to thermogravimetric analysis (TGA) and differential scanning colorimetry (DSC). Meanwhile PETAC and CS/PETAC were characterized using scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), X-ray fluorescence (XRF), Fourier transformed infrared spectroscopy (FT-IR) and nitrogen adsorption/desorption (N<sub>2</sub>-BET). The N<sub>2</sub>-BET results revealed an increase of the specific surface area from 6.75 m<sup>2</sup>/g to 1282.0 m<sup>2</sup>/g for PETAC and CS/PETAC. The results of characterization indicated the key role played by plastic wastes to enhance the structural and functional properties of CS/PETAC. The RhB removal from the aqueous solution onto PETAC and CS/PETAC was found to be independent of pH, with an optimal contact time of RhB removal within 10 min for materials. The non-linear adsorption isotherm data for the adsorption process showed that the Langmuir and Freundlich models best fitted the RhB adsorption onto PETAC meanwhile only the Freundlich adsorption isotherm gave the best fit for CS/PETAC according to the correlation coefficient value closed to unity. The pseudo-first and pseudo-second-order kinetic models best described the RhB dye removal on both adsorbents. Additionally, the Elovich model confirmed that chemisorption was the main mechanism followed. These findings proved that CS seeds and PET wastes are low-cost precursors that should be given an added value by transforming them into an outstanding carbon material for dye removal in liquid effluent.
文摘Objective:To evaluate the anti-infectious and antioxidant activities of hydroethanolic extract of Canarium schweinfurthii on broiler chickens infected by Salmonella enterica serovar Typhimurium,known to be threatening public health.Methods:Animals were divided into six groups of eight animals per group:the normal control group,negative control group,positive control group and three test groups receiving the plant extract at 5,19 and 75 mg/kg bw,respecively.The evolution of the disease as well as the effectiveness of the treatment were monitored by stool culture from the second day post infection until the end of the treatment.In addition,the effects of treatment on growth performances and feed conversion efficiency of broilers were evaluated.For the assessment of antioxidant status,enzymatic and non-enzymatic biomarkers such as catalase,glutathione peroxidase,malondialdehyde and nitric oxide were evaluated in the serum and tissues of animals.Results:The infected chickens treated with oxytetracycline recovered on day 7 after treatment,while animals treated with 19 and 75 mg/kg of Canarium schweinfurthii extract recovered on day 9 and those with 5 mg/kg of the extract on day 10.Salmonella infection caused a decrease on catalase and glutathione peroxidase activities;the administration of various doses of Canarium schweinfurthii extract increased these enzymatic activities.Animals receiving the extract at 5 mg/kg showed a significant increase in catalase activity in serum,heart and lungs while all concentrations of the extract significantly increased glutathione peroxidase activity in the serum,liver and spleen.Concerning non-enzymatic biomarkers,Salmonella infection caused a significant increase of nitric oxide and malondialdehyde concentration in the liver and lungs.Treatment with 75 mg/kg of the extract significantly reduced nitric oxide concentration in the heart and lungs while each dose of the extract reduced and normalized the malondialdehyde level in the serum.Additionally,malondialdehyde production was significantly decreased in the liver,heart and lungs after administration of Canarium schweinfurthii extract at all doses.Conclusions:The hydroethanolic extract of Canarium schweinfurthii attenuates oxidative stress,and is effective in the treatment of avian salmonellosis.
文摘The aim of this work was to develop and characterize a polyester matrix composite material based on Canarium schweinfurthii Engl core granule. The particle size and the mass fractions of these cores used as fillers in this composite were the two optimization parameters. The experimentation of the twelve sample areas was based on the following optimization parameters: Three particles sizes of 80 1 2 3 ·m-3, which allows us to admit that this composite belongs to the family of light materials. The maximum compressive stress at break was obtained for the formulation 40% filler of size T3. This compressive stress at maximum rupture is in the range of 199.14 MPa. From 0% to 45% of filler, the flexural Young’s modulus of the composite increases whatever the particle size. The highest value is obtained for T2 particle size, i.e. 13.11 GPa. The static friction coefficient of the composite on wood increases as the filler content varies from 0.30 to 0.42. Thus, in view of the properties obtained, this composite can be used as alternative solutions in industrial applications, for the manufacturing of shoe heel, house ceiling, floors for housing and table support.
文摘The purpose of this study is to determine the morphological, microstructural characteristics and water diffusion parameters of the Canarium schweinfurthii (CS) shellnut. This work is part of a vast project to valorize the above-mentioned cores for possible industrial use as charges in composites or abrasives materials. The study was based on the characterization of intrinsic physical characteristics of the coreshells scanning electron microscopic (SEM) observations desorption, adsorption and absorption kinetics. The water diffusion phenomenon was modeled and it appears that the Page model well predicted the kinetic of drying, absorption and adsorption. The effective diffusion coefficient and the energy of activation were calculated at three isothermal temperatures (50<span style="white-space:nowrap;">°</span>C, 70<span style="white-space:nowrap;">°</span>C and 90<span style="white-space:nowrap;">°</span>C). There was a tendency for hysteresis in the sorption-desorption cycles. These results strongly predicted the possibility of using these products as a filler in composites, clay building materials and cement because of their high water diffusion stability on a macroscopic scale.
文摘Two forms of A. halimus shrubs: erect habit (A. halimus) and bushy habit shrub (A. schweinfurthii) are used naturally isolated by a considerable distance from each other and occupy the same area. To explore the effect of natural isolation on the genetic basis of the two forms, Start Codon Targeted (SCoT) and the phylogenetic relationships of A. halimus by sequencing ITS1-5.8S-ITS2 regions of the ribosomal DNA are used. Significant isolation-by-distance relationship was found (r = 0.62, P = 0.001). Soil factors did not influence molecular variations. The natural isolation of A. halimus habitats restricts gene flow among the populations and the observed high within-population genetic diversity (74.19%) in this species is best explained by its outcrossing behaviour, long-lived individuals and overlapping generations. The UPGMA analysis of the SCoT results showed that all the studied populations were divided into two discrete genetic groups with significant separation of the two forms in Burg El-Arab area (Populations 1 and 2) and insignificant separation between two forms in El-Hammam area (population 5 and 6). The sequencing of the ITS1-5.8S-ITS2 rDNA regions also showed the insignificant separation of the two A. halimus forms. We conclude that gene flow depending on habitat fragmentation was the main factor affecting the population genetic differentiation. We suggest that the two forms do not merit specific rank in presence of interference between the two forms and absence of a breeding barrier fail to separate the different populations when they become sympatric.
文摘Equilibrium moisture contents (EMC) of wood species are very necessary in the utilization of these in service. This study investigated the EMC of five lesser utilized species of Ghana and compared it with that of three European species. Sixteen randomly sampled specimens of each of the eight species (heartwood and sapwood) with dimensions 3 cm × 3 cm × 3 cm were exposed at various relative humidity conditions of 30%, 45%, 60%, 75% and 90% in a temperature and humidity-controlled climate chamber at a temperature of 25°C in accordance to German standard DIN 52182. The species are Albies alba, Fagus sylvatica and Picea abies which are European species and Amphimas pterocarpoides, Antiaris toxicaria, Canarium schweinfurthii, Celtis zenkeri and Cola gigantea are wood species from Ghana. Internal wood temperature and humidity were measured with datalogger. Samples were considered to have reached equilibrium at any given humidity when the daily weight changes were less than 0.1 mg according to German standard DIN 52183. After the last measurements of the weight changes, the samples were dried at 103°C until there was a constant weight. The five tropical hardwoods had low sorption values recorded and high sorption values for the European species and this could be attributed to differences in the microstructure of these woods.