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This study presents the first report on the kinetic parameters of micro-nano interaction of lithium triborate microparticles doped with zinc oxide nanoparticles (LBZ) in 0.1 to 0.4% dopant concentrations. The parent-dopant mix was synthesized using high-temperature solid-state method. The materials were subjected to X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and differential thermal analysis (DTA) to ascertain their structural, physical properties as well as gamma irradiation and thermoluminescence (TL) analysis for their dosimetric properties. XRD and DTA confirmed the formation of polycrystalline lithium triborate compounds, while SEM and EDS showed the presence of the dopant. TL analysis presented a simple glow curve structure with the main temperature peak for different dopant concentrations varying from 243 to 327°C. The activation energy (E) and frequency factor (s) were calculated for each peak shape parameter τ (low temperature half width), δ (high temperature half-width) and ω (total half width) using Chen's peak shape (PS) method and the order of kinetics was deduced from the symmetry factor (μg) and gamma dose–response curves. The activation energy and frequency factor with respect to the peak shape parameters Eτ, Eδ, Eω and sτ, sδ, sω across the dopant concentrations were in the range of 1.14 to 2.2 eV and 3.92 × 1010 to 7.71 × 1022 s−1, respectively. Comparing the methods for the determination of the order of kinetics, LBZ 0.2% agrees with the conditions of first-order kinetics, while second-order kinetics is assigned to LBZ 0.1, 0.3 and 0.4%. The results present simple glow curve structure which relates to stability, high-temperature peaks and E values which correspond to deep trap states. [ABSTRACT FROM AUTHOR]

This study investigated two classifications of wood cellulose of particle sizes 300 µm to 424 µm and 600 µm to 849 µm. The cellulose samples were characterized using X-ray diffraction (XRD), energy-dispersive Xray spectroscopy (EDX), and scanning electron microscopy (SEM). The cellulose crystal revealed a preferred orientation along the (200) plane for the most prominent peak. The XRD diffractogram revealed an orthorhombic structure obtained from the powder diffractogram file (PDF). Furthermore, the crystallinity index and crystalline size were calculated and the increase in crystalline size of the isolated cellulose indicated higher thermal stability. The EDX analysis showed chemical components of carbon (C), sodium (Na), chlorine (Cl), and oxygen (O) in the isolated cellulose. The morphology of the cellulose appeared as strings of fibres. The isolated cellulose has applications in the production of biomaterial, thermal insulating devices, and domestic applications. [ABSTRACT FROM AUTHOR]

This study examines the dynamic compression and thermo-physical properties of some wood particles obtained from Akure, south local government area, Ondo State, South Western Nigeria. These wood particles are of the species of Celtis zenkeri and Celtis philippensis of the Ulmaceae family. The samples were possessed into different particle sizes (300, 600 and 850 μm) and subjected to varied compacting pressures (2.60-3.0 MPa). The density and specific heat capacity of the wood samples were determined using weighing displacement methods and temperature dependent model while the thermal diffusivity was estimated from other thermal properties. The results revealed significant variation in the values of the specific heat capacity as a result of change in pressure for all the wood samples considered. The density of wood samples lies between 4.51×102 -7.32×102 kg/m3 and the specific heat capacity values obtained for the samples fall within the range of 1.28×103-1.33×103 J/kg/K. It was also noted that the thermal diffusivity obtained falls within the range of 1.37×10-7-2.10×10-7 m2/s for the wood materials considered. However, the values of the densities, specific heat capacities and thermal diffusivities of the samples were found to change as the compacting pressure increased due to decreased in porosity. The implication of the study is that the materials have potential for use in polymer applications and the fabrication of film based photographic devices. [ABSTRACT FROM AUTHOR]

Air and soil temperatures are important agrometeorological variables with several applications. Understanding the complex behavior of air and soil temperatures, as well as their interaction, will help in agricultural planning. Multifractal detrended fluctuation and multifractal cross-correlation analysis of air and soil temperatures were carried out in three locations (Akure, Abuja, and Bauchi) within a tropical country, Nigeria. Monthly and annual air and soil temperatures measured at 5 min intervals for a period of 1 year were obtained and analyzed for multifractality. There is evidence of seasonal dependence in the multifractal behavior of monthly soil temperature. Monthly temperatures (air and soil) were found to have higher degrees of multifractality than annual temperatures. Furthermore, latitudinal dependence was observed in the multifractal behavior of air and soil temperatures. The cross-correlation between air and soil temperatures also shows multifractality with persistence at the monthly scale and anti-persistence at the annual scale. This work has shed light on the complex relationship between air and soil temperatures, and the results will be useful in modeling the two variables.