The isolation of cellulose has found considerable applications recently due to its attractive characteristics. Cellulose from Albizia gummifera of different size classifications (425 μm–599 μm and 600 μm–849 μm) was investigated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analyses. The crystal plane of the preferred orientation was at (020) for the most prominent peaks. The two size classifications have a strong broad peak around 3320 cm⁻¹ (425 μm–599 μm), and 3330 cm⁻¹ (600 μm–849 μm), which corresponds to a different stretching mode of O–H. High percentages of carbon (C) and oxygen (O) were noticed among the elements observed in the two size classifications. The crystallinity index (CrI) obtained for the two sizes were 61.1% for 425–599 μm, and 55.8% for 600 μm–849 μm. The 425 μm–599 μm size classification had a greater crystallinity index than the 600 μm–849 μm size classification, which indicates a stronger capacity for reinforcing. These particles were also effective as fillers in composite materials. The results revealed that Albizia gummifera cellulose possessed promising potential for device applications and capable of being used in the preparation of composite materials.

Influence of size classification on the properties of cellulose materials has been a subject of neglect over the years. Researchers had the opinion that there exist no significant difference between the characteristics of bulk particulate materials and sizes of their constituents. However, it has been affirmed that increase in crystallinity index, increases the strength properties of cellulose materials. Therefore, there is need to establish the influence of size classification as it affects the properties of cellulose materials. This study focused on the influence of size classifications on the structural and solid State characterization of cellulose obtained from wood dust. The structure of the cellulose composed principally of crystalline cellulose (I and II) and amorphous cellulose. The crystallinity and the inter-planar spacing revealed different structural properties for the two size classifications. The elemental composition consists of Carbon (C), Oxygen (O), Sodium (Na) and Chlorine (Cl) with Carbon having the highest percentage. The surface morphology of the isolated cellulose appears fiber -like for the size classifications examined. The isolated cellulose exhibits good mechanical and solid state properties with promising applications in device utilization. Within the limit of the research, size classification is noted to influence the characteristics of the cellulose materials.

Structural Characterization and Solid State Properties of Thermal Insulating Cellulose Materials of Different Size Classifications

This work presents the characteristics of the single event transient (SET) induced by a single heavy ion in the inverse mode NPN-SiGe HBT simulated with the Silvaco TCAD toolkit. The designed SiGe HBT technology structure was built on the DevEdit simulator and simulated on Deckbuild using device and radiation effect simulations. The characteristics of device SET distribution, including transient pulse current, corresponding collection charge, pulse current peak, and full width at half maximum (FWHM) levels, etc, were simulated and compared as they changed with heavy ion LETs (0.2 pC μm⁻¹ ∼ 1.0 pC μm⁻¹), striking angles (30° ∼ 120°), and device emitter bias voltage settings (0.6 V ∼ 1.8 V). Meanwhile, the electrostatic potential distribution was found to be impacted by the heavy ion SET at the initial time moment when the heavy ion began to strike the surface of the device. The mechanisms for SET variation and its influence on the device potential under different conditions were primarily analyzed and discussed.

The degradation characteristics of silicon-germanium heterojunction bipolar transistors (SiGe HBTs) under different bias modes (forward, cutoff and saturation) during irradiation were reported after multiple pulsed neutron-gamma irradiation at room temperature. The radiation-sensitive parameters of the test samples, including base current I _B , collector current I _C and DC current gain $\beta $ , were measured and compared before and after every reactor n- $\gamma $ pulse irradiation. The test results show that I _B increased with increasing fluence, and I _C slightly increased in the low base-emitter voltage V _BE region (approximately from 0.4 V to 0.5 V) and decreased in the high-V _BE region (approximately V _BE >0.5 V). Moreover, the degradation degree of the test samples was different under different bias conditions. The performance of the test samples under cutoff bias mode displayed the most serious degradation, while those under forward bias mode suffered minimum damage. Meanwhile, the time-dependent annealing characteristics of the DC current gain for SiGe HBTs at various bias conditions were compared and analyzed.