Suranaree Journal of Science and Technology

EFFECTS OF ULTRASOUND AND PULSED ELECTRIC FIELD IN EDIBLE INSECT PROTEINS - A REVIEW

Arun Joshy — 2025-09-08

The increasing global demand for sustainable protein sources amid environmental concerns related to conventional livestock production has necessitated the exploration of alternative food ingredients, particularly edible insects. This review investigates the effects of Pulsed Electric Field (PEF) technology and ultrasound on the extraction efficiency and functional properties of various insect proteins. The findings indicate that PEF treatment significantly improves protein and fat extraction yields, with higher intensities enhancing antioxidant activity. Conversely, ultrasound enhances the digestibility and solubility of extracted proteins, contributing to improved emulsifying and foaming characteristics essential for food applications. Comparative analysis shows that while both methods enhance protein recovery and functional qualities, PEF demonstrates superior results in optimizing extraction efficiency from insect sources like crickets, whereas ultrasound facilitates the production of high-quality protein isolates. Both technologies represent promising avenues for improving the viability and attractiveness of edible insects as sustainable protein sources, addressing the growing challenges of food security and environmental sustainability.

EVOLUTION OF PHASE FORMATION, MICROSTRUCTURE, AND ELECTRICAL PROPERTIES OF BaTi0.91Sn0.09O3 LEAD-FREE CERAMICS FOR DIFFERENT CALCINATION AND SINTERING TEMPERATURES

Wiwat Pattanakasem — 2025-08-20

Lead-free BaTi_0.91Sn_0.09O₃ (BTS) ceramics were fabricated by the conventional solid-state reaction method. The evolution of phase, microstructure, dielectric, and ferroelectric properties of BTS powders and ceramics was examined at different calcination (1175-1250°C for 4 h.) and sintering (1375-1450°C for 2 h.) temperatures. X-ray diffraction (XRD) revealed that the calcined powders had perovskite structures, with a secondary BaSnO₃ impurity phase when calcined below 1200°C. The BTS ceramics displayed a secondary Ti_0.85Sn_0.15O₂ phase at a sintering temperature of 1375°C, while no impurity phases were detected at 1400-1450°C. Rietveld refinement indicated coexisting orthorhombic (O), tetragonal (T), and cubic (C) phases in all samples. The O phase increased with sintering temperatures up to 1425°C before decreasing, while the T and C phases decreased for sintering temperatures up to 1425°C before increasing. When the sintering temperature increased from 1375°C to 1425°C, the density, dielectric constant at the Curie temperature (ε_C), and maximum polarization (P_max) increased from 5.90 to 5.98 g/cm³, 9,533 to 12,538 and 15.07 to 15.36 μC/cm², respectively, before decreasing. In contrast, the dielectric loss (tan δ), remanent polarization (P_r), and coercive electric field (E_c) decreased from 0.036 to 0.020, 8.42 to 7.48 μC/cm², and 3.49 to 1.86 kV/cm, respectively, when the sintering temperature increased from 1375°C to 1425°C, before slightly increasing. The BTS ceramic sintered at 1425°C showed the highest density, a well-packed microstructure, superior dielectric properties, and high P_max. The increased orthorhombic phase content reduced P_r and E_c, making this ceramic suitable for dielectric capacitor applications.

A STUDY OF THE PHYSICAL AND OPTICAL PROPERTIES OF PINK GLASSES MADE FROM SUGARCANE LEAVES IN NAKHON PATHOM PROVINCE

Pornnapha Mangthong — 2025-08-07

This research aims to study of the physical and optical properties of pink glasses made from sugarcane leaves in Nakhon Pathom Province. Sugarcane leaves were subjected to baking at temperatures of 1000°C. It was observed that as the SiO₂ content increased, the color of the glass changed. The glass formula was designed according to the ratio of (40-x) SiO₂: 20B₂O₃: 25Na₂O: 15CaO: xEr₂O₃ mol%, where x represents the concentration of Er₂O₃ in the glass. The ground mixture was melted in a porcelain crucible at a temperature of 1,200°C in an electric furnace for 3 hours under normal atmospheric conditions. Subsequently, the homogeneous melts were formed and quenched into a preheated graphite mold, followed by immediate annealing at 500°C. The glass was then slowly cooled to room temperature. Afterward, the colored glass samples were analyzed, revealing that the density and refractive index of the glass samples ranged from 2.6060 to 2.7548 g/cm³ and 1.5465 to 1.5664, respectively. All glass samples exhibited a hardness value of 5.5 on the Mohs scale.

STATISTICAL SIGNIFICANCE OF DIFFERENCES MAGNESIUM DIBORIDE SUPERCONDUCTING TRANSITION TEMPERATURE MODELING

Warapol Kasemsan — 2025-08-18

An extensive study has been done on a modeling approach that helps forecast the critical temperature of magnesium diboride (MgB₂) materials. To determine the statistical importance of changes in modeling techniques, investigations must be able to consistently distinguish between systematic approach impacts and mistakes caused by modeling approach variance. In this study, researchers used analysis of variance and correlation analysis to determine the statistical significance of differences in modeling method variation. The resulting results were compared to the critical temperature estimated from lattice parameter change data using gaussian process regression (GPR), support vector machine (SVM), and linear regression with natural logarithm transformation (LRNLT).

IN SILICO IDENTIFICATION OF SECONDARY METABOLITES FROM AQUATIC STREPTOMYCES ISOLATE WITH ANTIYEAST AND ANTICANCER ACTIVITIES

Jirayut Euanorasetr — 2025-08-15

This study explored the potential of bioactive metabolites from Streptomyces strain WHD3007-4. Isolated from a Nile tilapia pond, aquatic Streptomyces sp. WHD3007-4 was cultured in four media (International Streptomyces Project-2 Medium (ISP2), 301, Starch Casein Broth (SCB), and Bennet’s Broth (BN). Its secondary metabolites were extracted using ethyl acetate and acetone at a ratio of 15:2 (v/v). The cytotoxicity of all crude extracts on the human colorectal cancer cell line HCT-116 was assessed using the MTT assay. The percentage of viable HCT-116 cells was lowest with Streptomyces sp. WHD3007-4 in the SCB medium (36.20%). The antiyeast activity of the crude extract from Streptomyces sp. WHD3007-4 in SCB medium was assessed against Candida tropicalis (TISTR No. 5136) using the disk diffusion method. The crude extract effectively inhibited C. tropicalis growth at 2 mg. Known compounds in the crude extract from Streptomyces sp. WHD3007-4 in different media were identified using liquid chromatography-tandem mass spectrometry, with the data processed using MZmine 3 for molecular networking and spectral library searching on the Global Natural Products Social Molecular Networking (GNPS) web platform. Several candidate anticancer molecules were identified: kynurenic acid, brevianamide F, N-(2-hydroxyphenyl) acetamide, and decumbenone A. These results suggest that Streptomyces sp. WHD3007-4 is a potential source of antiyeast and anticancer agents.

ENHANCING THE EFFICIENCY OF CEMENT-BASED TRIBOELECTRIC NANOGENERATORS THROUGH OPTIMIZED ELECTRODE CONFIGURATIONS

Thanongsak Nochaiya — 2025-09-08

Cement-based materials, commonly used in construction, show great potential as triboelectric nanogenerators. However, the electrode type for cement-based triboelectric nanogenerators (CTENGs) significantly influences not only the electrical output but also the durability of the device. Therefore, this study aims to investigate the effects of electrode type and the distance between the electrode and the sample surface on the electrical output performance of CTENG. The CTENG with stainless steel plate and wire mesh electrodes was evaluated in a vertical contact-separation mode. The results revealed that the wire mesh electrode not only improved the electrical output but also
enhanced the durability of the CTENG compared to the plate electrode. Additionally, greater opencircuit voltage and short-circuit current values were obtained by decreasing the distance between the electrode and the sample surface. At distance of 1 mm, the CTENG achieved a power density of up to 139 mW/m² when connected to an external load of 10 MΩ. This study offers a promising strategy to enhance the performance and durability of CTENGs, enabling their efficient use as energyharvesting materials.

ELECTRICAL AND MAGNETIC PROPERTIES OF MULTIFERROIC Co0.6Zn0.4Fe1.7Mn0.3O4 DOPED 0.99Bi0.47Na0.47Ba0.06Tio3-0.01Ba(Sn0.70Nb0.24)O3 CERAMICS SYNTHESIZED VIA THE SOLID-STATE COMBUSTION TECHNIQUE

Anupong Luangpangai — 2025-08-19

Multiferroic (1-x)[0.99Bi_0.47Na_0.47Ba_0.06TiO₃-0.01Ba(Sn_0.70Nb_0.24)O₃]-xCo_0.6Zn_0.4Fe_1.7Mn_0.3O₄ (abbreviated as BNBT-BSN-xCZFMO) ceramics with x ranging from 0 to 0.20 were fabricated using the solid-state combustion technique. The effect of varying BNBT-BSN : CZFMO ratios on the phase structure, microstructure, electrical and magnetic properties was investigated. X-ray diffraction (XRD) analysis of pure BNBT-BSN showed a perovskite structure with rhombohedral and tetragonal phases. The doped BNBT-BSN-xCZFMO ceramics displayed coexisting rhombohedral, tetragonal, and cubic spinel phases, with the cubic spinel phase increasing when the CZFMO content increased. In addition, the XRD peaks shifted to higher angles as the CZFMO content increased, indicating a decrease in lattice parameters. The dielectric constant decreased with higher CZFMO content and higher frequencies. The pure BNBT-BSN ceramic exhibited a saturated P-E loop with a P_max of 33.2 µC/cm², P_r of 26.1 µC/cm², and an E_c of 14.5 kV/cm. With increased CZFMO content, non-saturated and bloated P-E loops with lower P_max, P_r, and E_c were observed, implying a rise in the leakage current. The addition of CZFMO induced ferromagnetic behavior in the ceramics, leading to an increase in M_s and a reduction in H_c as CZFMO content increased. The magnetoelectric coupling coefficient of BNBT-BSN-xCZFMO ceramics continuously increased with higher CZFMO content.

STUDY OF PHYSICAL AND OPTICAL PROPERTIES OF SUGARCANE LEAF ASH GLASS DOPED WITH COPPER OXIDE

Pattraporn Saengka — 2025-08-19

In this research, the physical and optical properties of sugarcane leaf ash doped with copper ions in glass were investigated. The composition of sugarcane leaf ash was analyzed at different sintering temperatures using X-ray fluorescence (XRF) spectroscopy, revealing the highest SiO₂ content (69 wt%). The glass formula was developed based on the ratio (50-x)SiO₂ (with sugarcane leaf ash substituting for SiO₂ and CaO): 25B₂O₃: 10Na₂O: 8CaO: 7SrO: xCuO, where x represents the concentration of copper oxide (0.00, 0.10, 0.20, 0.30, 0.40, and 0.50 mol%). The results showed that the density and refractive index increased with increasing CuO concentration, while the molar volume decreased. The absorption spectra of the glass in the wavelength range of 350-1,100 nm was measured and showed a peak around 775 nm, corresponding to the ²B₁g → ²B₂g transition of Cu²⁺. The studied glass exhibited greenish-blue color coordinates, confirmed by CIE Lab* color measurements.

INVESTIGATION OF ELECTRONIC STABILITY CONTROL PERFORMANCE IN EXTREME CONDITIONS OF TIRE INFLATION, SPEED AND WEIGHT DISTRIBUTION

Baskar Ponnusamy — 2025-09-04

Electronic Stability Control(ESC) systems are crucial safety features designed to assist drivers in maintaining control of their vehicles during dynamic driving situations. However, the effectiveness of ESC may vary depending on many factors but we investigate the factors such as tire inflation pressure, vehicle speed, and weight distribution. Understanding how these parameters influence ESC performance is essential for enhancing vehicle safety across a range of driving scenarios. An investigation has been carried out to simulate the functioning of Electronic Stability Control and evaluate its performance under these varied parameters in a Double Lane Change test (DLC). The DLC is chosen as it replicates a real-world scenario ideal for assessing the electronic stability control system's effectiveness. The results revealed that ESC performance was significantly impacted by tire pressure, speed, and weight distribution of the vehicle. In conditions where tire pressure and speed were suboptimal, ESC effectiveness was notably compromised, posing a risk of dangerous accidents. Additionally, loading the vehicle with weight distributed on a single side was found to be not recommended. However, in other conditions, ESC demonstrated positive or mildly positive effects, highlighting its potential to enhance vehicle stability and safety

DISCOVERING THE POTENTIAL OF NiO: A FIRST-PRINCIPLES DFT STUDY ON ANODE PROPERTIES FOR LITHIUM-ION BATTERIES

Mohd Hazrie Samat — 2025-08-23

Transition metal oxides such as nickel oxide (NiO) are receiving significant research attention as potential anode materials for lithium-ion batteries (LIBs). The structural and electronic properties of NiO are calculated using density functional theory (DFT) method. The computed lattice parameters are in close agreement with experimental values, showing the precision of the GGA-PBEsol functional compared to LDA and GGA-PBE functionals. The indirect band gap of NiO calculated using GGA-PBEsol+U with U = 8 eV is approximately 3.84 eV, matching well with experimental values ranging from 3.60 to 4.47 eV. The density of states (DOS) analysis reveals hybridization between O 2p and Ni 3d orbitals, suggesting improved lithium-ion diffusion pathways. The bond population analysis indicates weak ionic bonding with a value of 0.32 to 0.50, leading to mechanical stability during lithium intercalation. These findings show the usefulness of NiO as an anode material in LIBs. However, the poor electronic conductivity of NiO remains a limitation, which could be solved through strategies such as compositing with conductive materials or doping. Future research should focus on optimizing these strategies to further enhance the electrochemical performance of NiO-based anodes.

PHASE FORMATION AND ELECTRICAL PROPERTIES OF Ba0.91Ca0.09Ti0.916Sn0.084O3-0.1WT%ZnO -0.1WT%MnO2 LEAD-FREE FERROELECTRIC CERAMICS SYNTHESIZED VIA THE SOLID-STATE COMBUSTION METHOD

Sununta Yimsabai — 2025-08-20

This work investigated the effect of firing temperatures on the phase formation, microstructure, and electrical properties of Ba_0.91Ca_0.09Ti_0.916Sn_0.084O₃-0.1wt%ZnO-0.1wt%MnO₂ (BCTS-ZnMn) lead-free ferroelectric ceramics synthesized via the solid-state combustion method. Glycine was used as fuel to reduce the synthesis temperature. The samples were calcined at temperatures from 1050 to 1250°C (in 50°C increments) for 3 h and sintered from 1250 to 1450°C (in 50°C increments) for 3 h. A pure perovskite phase was found in the powders calcined above 1100°C. The phase structure, microstructure, dielectric and ferroelectric properties of the ceramics were examined. The X-ray diffraction (XRD) analysis for the ceramics revealed the presence of tetragonal (T) and orthorhombic (O) phases in all the ceramics. The average particle size and average grain size increased with increasing firing temperatures. The density, dielectric constant at the Curie temperature (ɛ_c), P_r and P_s tended to increase with increasing sintering temperatures, up to 1400°C, and then decreased at 1450°C. The ceramic sintered at 1400°C exhibited the highest density (5.89 g/cm³), dielectric response (ɛ_c = 13324) and good ferroelectric behavior (P_r = 8.67 µC/cm², P_s = 17.92 µC/cm² and E_c = 0.99 kV/cm)

FOOD INNOVATION FOR EXTENDING SHELF LIFE OF WHITE SHRIMP, TILAPIA, AND NAM DOK MAI MANGO WITH CHITOSAN EXTRACTED FROM LEFTOVER WHITE SHRIMP SHELL

Bpantamars Phadungchob — 2025-08-19

This study repurposes white shrimp shells, an agricultural waste, to extract chitosan—a natural biopolymer with antimicrobial properties—for enhancing food safety and extending shelf life. Chitosan was extracted using a simple, cost-effective process involving chemical treatments and drying. The extracted chitosan, characterized as high DA chitosan (% DA = 75.93 ± 1.40) with enhanced solubility, with functional groups similar to those found in commercial chitosan. Preservation tests demonstrated that the extracted chitosan effectively extended the shelf life of unpeeled shrimp by 3-5 days, peeled shrimp by 1-2 days, and tilapia by 2-3 days while maintaining sensory quality, including color, pH stability, and odor control. For Nam Dok Mai mangoes, chitosan coatings at the peduncle area preserved marketable quality for up to 10 days. This method provides a cost-effective, sustainable solution for local producers, promoting value-added agricultural practices and benefiting both seafood and fruit preservation.

INCREASED RHINACANTHIN PRODUCTION IN RHINACANTHUS NASUTUS HYDROPONICS BY DUAL ELICITATION USING CHITOSAN AND TRICHODERMA HARZIANUM

Thongtham Suksawat — 2025-08-07

A highly efficient hydroponic cultivation system was developed to enhance rhinacanthin production in Rhinacanthus nasutus. Within this framework, dual elicitation using chitosan (CHI) and Trichoderma harzianum extract (THE) was identified as a promising technique, strategically employed to increase the overall yield of rhinacanthins. R. nasutus hydroponics were treated with CHI (0.15 mg ml^-1) and THE (1.0 mg ml^-1) either simultaneously or sequentially, with elicitor exposure periods ranging from 24 to 96 h. The total rhinacanthin content (rhinacanthin-C, -D, and -N) in roots and leaves was analyzed using HPLC. Simultaneous dual elicitation with CHI and THE resulted in lower rhinacanthin levels in both leaves and roots compared to single elicitation with either agent. Among the treatments, the highest rhinacanthin contents in the leaves (7.05% w/w) and roots (9.65% w/w) were observed with sequential dual elicitation, in which 0.15 mg ml^-1 CHI was applied for 48 h, followed by 1.0 mg ml^-1THE for 24 h and 72 h, respectively. In contrast, a reversed sequential dual elicitation, in which 1.0 mg ml^-1THE was applied for 24 h followed by 0.15 mg ml^-1 CHI for 72 h and 48 h resulted in rhinacanthin contents of 7.34% and 7.32% w/w in the leaves and roots, respectively. The present study demonstrates an effective approach for enhancing rhinacanthin content in hydroponically cultivated R. nasutus through sequential dual elicitation using CHI and THE.

TRUE COLOR ANALYSIS OF PLANT PIGMENT BASED ON IMAGE REALIZATION STEGANOGAPHY TECHNIQUE

Warapol Kasemsan — 2025-08-29

Digital steganography is the practice of concealing secret messages behind seemingly normal digital data that does not raise suspicion. This study introduces a novel method of genuine color analysis of plant pigments that resembles a thin film coated on paper chromatography, by analyzing digital images of plant pigments pixel by pixel, we can correlate the color data with the corresponding chromatogram, providing insights into the plant's biochemical composition, referred to as Image Realization Steganography (IRS). This is a mapping-based technique that hides the image cover file in an undetectable manner. The image cover is only intended for reference. The suggested method provides a cover-secret mapping that reveals the true color of a concealed plant pigment without affecting the reference image. Comparing the acquired data to IRS to estimate the true color of Wolffia globosa (L.) Wimm pigment was presented. The conclusions indicate that steganography is a viable option for determining the true color of plant pigments in the form of color codes, specifically RGB and CMYK.

COMPUTATIONAL STUDY ON STRUCTURAL, ELECTRON STATES, AND MUON TRAPPING SITES IN GUANINE

Wan Nurfadhilah Zaharim — 2025-08-18

Knowledge of muon trapping sites in matters is needed in the interpretation of Avoided Level Crossing-Muon Spin Resonance (ALC-µSR) experiment. Additionally, accurate computation on the trapped muon hyperfine interaction is instrumental in the planning of applied magnetic field strength for the experimental measurement. Density Functional Theory quantum mechanical method was employed to predict the most probable sites of muon addition in isolated guanine nucleobase. Utilizing B3LYP functional coupled with 6-311G++(d,p) basis set, the HOMO-LUMO gap was calculated to be 5.147 eV. The frontier molecular orbitals show significant delocalization characteristics. Molecular electronic potential map indicates that N2, O5, and N7 areas are favoured for alkylation. Out of eight possible muon addition sites, C8 was found to have the lowest total energy and therefore is the most probable location for the trapping of implanted muon. Natural Population Analysis reveals that the trapped muon is covalently bonded to the C8 atom with a bond order of 0.903. The calculated muon hyperfine coupling constant at the C8 site is 337.4 MHz. The applied magnetic field strength for ALC-µSR resonance to occur for C8 site is predicted to be around 14,000 Gauss. These findings provide valuable insights into muon behavior in nucleobases, contributing to a more precise interpretation of ALC-µSR experimental data and enhancing the design of future studies on muon interactions in biomolecular systems.

STUDIES OF PRESERVATION OF LOTUS POLLENS AND INTERSPECIFIC LOTUS BREEDING

Vichai Puripunyavanich — 2025-08-08

Lotus (Nelumbo nucifera) pollen viability was studied under various conditions, including 30°C room temperature, 8°C refrigerator, and -20°C freezer for storage periods of 7, 10, and 14 days, respectively. The pollens were stained with acetocarmine for pollen survival testing. Lotus pollens stored for 7 days at room temperature and 8°C refrigerator exhibited the highest viability percentages (88.00% and 89.00%, respectively). Subsequently, lotus anthers were irradiated with gamma rays at 0, 30, and 60 Gy and preserved at 8°C refrigerator for 7, 10, and 14 days. Examination of pollen viability showed that there was no statistically significant difference between the viability of pollens irradiated at 30 Gy and non-irradiated treatment after 7 days. However, over a storage period of 14 days, the survival percentage of 30-Gy irradiated pollen decreased more rapidly compared to the non-irradiated. Pollens from the mutant yellow lotus N. lutea were collected at Queen Sirikit Botanical Garden, Chiangmai, and stored under 8°C as the optimal condition for preserving lotus pollens and transferred to Thailand Institute of Nuclear Technology, Nakhon Nayok for interspecific crosses with white native lotus flowers (N. nucifera ‘Boontarik’). Only four plants survived and only one could flower. These cultivars successfully adapted to the Thai central plain climate and flowered after 4 months of planting. Plant characteristics were similar to Thai native ‘Boontarik’ lotus but its flowers showed creamy petals. This cultivar was unofficially named Nelumbo ‘Yellow Boontarik’.

ELECTRIC AND MAGNETIC PROPERTIES OF Ni0.475Zn0.475Li0.025Al0.025Fe2O4 DOPED (Bi0.5Na0.5)0.94Ba0.06TiO3 CERAMICS PREPARED BY THE SOLID-STATE COMBUSTION METHOD

Wiwat Pattanakasem — 2025-08-20

In this study, we synthesized (1-x)((Bi_0.5Na_0.5)_0.94Ba_0.06TiO₃)-x Ni_0.475Zn_0.475Li_0.025Al_0.025Fe₂O₄[(1-x)BNBT-xNZLAF] ceramics with x= 0, 0.05, 0.10, 0.15, and 0.20 using the solid-state combustion method. The phase formation, microstructure, and dielectric, ferroelectric, ferromagnetic, and magnetoelectric properties were investigated. BNBT and NZLAF powders were calcined at 750°C and 900°C for 2 h., respectively. The calcined powders were then mixed in various ratios to produce (1-x)BNBT-xNZLAF composites, which were sintered at 1125°C for 2 h. X-ray diffraction analysis indicated that undoped BNBT ceramics exhibited a typical perovskite structure with coexisting rhombohedral (R) and tetragonal (T) phases. With increasing NZLAF content, the cubic spinel (C) phase emerged with the R and T perovskite phases. Rietveld refinement indicated a higher percentage of the C phase as x increased. When x increased from 0 to 0.10, the average grain size and density increased (from 1.0 to 9.8 m and 5.45 to 5.61 g/cm³, respectively) followed by a drop at higher NZLAF levels. Doping BNBT ceramics with NZLAF resulted in a reduction in the dielectric constant (ε_r), dielectric loss (tan δ), and remnant polarization (P_r). The undoped BNBT ceramic showed a saturated P-E hysteresis loop, while NZLAF doped ceramics exhibited unsaturated P-E loops and increased leakage current. Magnetic measurements showed a transition from diamagnetic to ferromagnetic behavior with NZLAF doping. As x increased, the remnant magnetization (M_r), saturation magnetization (M_s), and magnetoelectric coefficient also increased (M_r»0.058 emu/g, M_s»3.594 emu/g, and ME_coefficient »2.64 mV/cm•Oe at x=0.25). These results suggest that NZLAF-doped BNBT ceramics hold potential for multiferroic material applications.

BANDGAP VOLTAGE REFERENCE USING TRIPLE CASCODE OPERATIONAL AMPLIFIER

Komal Duhan — 2025-08-18

Bandgap Voltage reference (BGR) circuits are crucial components in analog circuits. In this paper, a BGR circuit capable of obtaining a reference voltage of 1.0435 V is proposed. In the proposed BGR circuit, Miller compensated two-stage Triple Cascode Operational Amplifier (Op-Amp) has been used which achieves a higher gain of 104.1db and Phase Margin of 73.78 degrees with 1.8V supply voltage using 90nm technology. The proposed BGR circuit achieves 4.51 ppm/OK of temperature coefficient and 0.4375 mV/V of line regulation. The designed BGR circuit can be used in analog applications.

MCCUMBER ANALYSIS AND GAIN CROSS-SECTION OF Er3+ ACTIVATED GADOLINIUM PHOSPHATE OXYFLUORIDE GLASSES FOR BROADBAND COMMUNICATION MATERIALS

Anucha Thongkerd — 2025-09-01

Er³⁺ activated gadolinium phosphate oxyfluoride glasses have been prepared via melt-quenching process and measured the absorption and luminescence spectra. The absorption spectra of glasses have shown in UV-VIS and Near-infrared region. The absorption intensity of glasses was enhanced as a function of Er₂O₃ concentrations. With laser diode excitation at 980 nm, the emission in near infrared region has shown a prominent peak at 1536 nm (⁴I_13/2→⁴I_15/2) which is important peak for transmission windows. The absorption and emission measurements led to calculate the stimulated emission cross-sections by McCumber analysis. It was found to be 2.66×10^–20cm² for 2.0 mol% of Er₂O₃. Furthermore, the positive gain cross-section of glass is identified when the population inversion (P) is more than 0.4. It is pointed out the flat gain bandwidth in wavelength range 1400 - 1700 nm will be achieved when the P exceeds 40% which covered S, C and L bands.

TYPE 1.5 SUPERCONDUCTIVITY IN MAGNESIUM DIBORIDE SUPERCONDUCTOR: A GINZBURG-LANDAU APPROACH TO CRITICAL CURRENT DENSITY

Arpapong Changjan — 2025-08-18

In this study, we present a theoretical investigation into the temperature-dependent critical current density of MgB₂ superconductors. Using the Ginzburg-Landau theory, we explore the behavior of this superconductor within the framework of a free energy model, which has been adapted from the type-1.5 superconductor model. The theoretical calculations derived from this model are then compared with experimental data obtained for MgB₂ superconductors. The results demonstrate a notable correlation between the theoretical predictions and the experimental findings, offering new insights into the temperature-dependent properties of MgB₂ and potentially advancing the understanding of its superconducting behavior.