High-quality Materials Research Articles

Preliminary investigation of the effects of high-temperature thermal activation on the activity of graphite tailings and the mechanical properties of graphite tailings mortar

The disposal of graphite tailings, a byproduct of graphite mining, poses significant recycling challenges. This study explores eco-friendly cement mortar by partially replacing sand with activated graphite tailings, focusing on waste utilization. Activating the pozzolanic properties of graphite tailings at various thermal activation temperatures converts them into high-quality binder materials. Quantitative assessments of graphite tailings' activity, conducted through ion leaching tests and raw material diffraction analysis, produce an activity index Ka, evaluating their performance under different thermal activation temperatures. Variable testing of substitution rates and activation temperatures examines changes in mechanical properties, microstructure, and pore distribution of the graphite tailings mortar. Optimum results reveal a 30 % substitution rate and a 750°C activation temperature. Graphite tailings, as pozzolanic binder materials, enhance mortar strength by improving particle size distribution, reducing "micro-area bleeding" and "boundary effects". After thermal activation, reactive minerals on the tailings' surface undergo secondary hydration reactions with cementitious products, modifying chemical structures and micro-morphology at the interface. Semi-quantitative XRD analysis and FT-IR spectroscopy characterize the ensuing chemical reactions, unveiling molecular bond and functional group changes. The superior performance of thermally activated graphite tailings primarily stems from increased active SiO2 and Al2O3 post-activation. The active SiO2 and Al2O3 reacts with cementitious products to form C-(A)-S-H gels, filling micro-pores at the tailings-mortar interface, which is the key characteristic that enables graphite tailings to serve as high-quality pozzolanic binder aggregates. A predictive model for compressive strength, utilizing reference models from solid waste mortar concrete, quantifies the positive impact of chemical activation. The theoretical results obtained from this predictive model closely align with the experimental findings.

Optoelectronic effect of Al-based buffer layers on Al-doped ZnO thin transparent conductive films on flexible substrates

AZO (Al-doped ZnO) film is a transparent conductive film that offers a simple preparation process, low cost, non-toxicity, and excellent stability. It serves as a high-quality material extensively used in liquid crystal displays, solar cells, and other fields. In this study, AZO thin films were prepared on a PET substrate with an Al2O3 buffer layer using the magnetron sputtering method. The deposition parameters were optimized through the Taguchi method and Grey Correlation Analysis. The results demonstrate that the optimal deposition parameters for achieving superior photoelectric properties during the fabrication of AZO films are 100 W (radio frequency power), 1.0 Pa (sputtering pressure), 20 min (coating time), and 20°C (substrate temperature). Furthermore, the incorporation of an Al2O3 buffer layer enhances the quality of AZO film on PET substrate. This investigation successfully deposited uniform and highly efficient AZO thin films onto flexible PET substrates at low temperatures, thereby expanding their potential applications in flexible electronics.

INSTRUCTIONAL MATERIALS USAGE ON STUDENT ACADEMIC PERFORMANCE IN PHYSICS SUBJECT IN DAY SCHOOLS IN RWANDA A CASE OF NYARUGENGE DISTRICT

Students academic performance in science subjects and physics specifically has always attracted big concern among students, parents, teachers and the entire public community. The main purpose of this research was to assess the instructional materials usage on students academic performance in Physics subjects in day secondary schools in Nyarugenge District-Rwanda. It had three specific objective such as to identify the instructional materials used in physics subject in day secondary schools in Nyarugenge District, Rwanda, to assess the level of students academic performance in physics subject in day secondary schools in Nyarugenge district, Rwanda, to examine the challenges faced by teachers in preparation of instructional materials in physics subject in day secondary schools in Nyarugenge District, Rwanda, to determine the relationship between instructional materials and students academic performance in physics subject in day secondary schools in Nyarugenge district, Rwanda. This research was supported with Socio-cultural theory and attribution theory. The researcher used descriptive research design and correlational research design for data collections. The study employed different respondents including parents, students, teachers, and head teachers. The total number of participants was 520, comprising 100 teachers, 400 students and 20 head teachers. These participants were drawn from 20 selected schools across 10 sectors within Nyarugenge District, Rwanda. The Yamane formula was used to calculate the sample size of 226 respondents from target population of 520.Simple random sampling was used to select students and head teachers from secondary schools in Nyarugenge District. Purposive sampling was employed for selecting teachers based on their pertinent experiences in teaching physics subject. Researcher used questionnaire and interview guide as data collection instruments where questionnaires was designed to gather information from students, while interview guides was tailored for teachers and head teachers selected from secondary schools.The findings, summarized in Table 4.7, reveal a strong and statistically significant correlation between instructional materials and students academic performance. The Pearson correlation coefficient of 0.911 indicates a very high positive correlation, suggesting that as the quality and availability of instructional materials increase, students academic performance in physics also tends to improve. The strong correlation signifies that well-designed, up-to-date, and diverse instructional resources can significantly enhance students understanding of the subject matter, leading to better academic outcomes. The implications of this strong correlation for educational practice are considerable. Schools and educators should prioritize the development and provision of high-quality instructional materials, including textbooks, digital resources, laboratory equipment, and supplementary materials. Ensuring that these resources are current, relevant, and accessible can create a more engaging and effective learning environment for students. It reveals a strong positive relationship between instructional materials and academic performance, with an R Square value of 0.829. This indicates that approximately 82.9% of the variance in students academic performance can be explained by the quality of instructional materials provided. This strong predictive capability underscores the importance of these resources in determining academic success. The Ministry of Education should implement regular and systematic professional development programs for teachers focused on innovative teaching methodologies. Background:The academic performance of students in science, particularly physics, is a significant concern for various stakeholders. This research aims to assess the impact of instructional materials on students academic performance in physics at day secondary schools in Nyarugenge District, Rwanda. Methods:The study utilized descriptive and correlational research designs, involving 520 participants: 100 teachers, 400 students, and 20 head teachers from 20 schools across 10 sectors in Nyarugenge District. A sample of 226 respondents was calculated using the Yamane formula. Simple random sampling was applied for students and head teachers, while purposive sampling was used for teachers. Data were collected through questionnaires for students and interview guides for teachers and head teachers. Results:Findings indicated a strong, statistically significant correlation (Pearson correlation coefficient of 0.911) between instructional materials and students academic performance in physics. An R Square value of 0.829 suggests that approximately 82.9% of the variance in academic performance can be explained by the quality of instructional materials. Conclusion: The study highlights the critical role of high-quality instructional materials in enhancing students understanding and academic outcomes in physics. It recommends that schools prioritize the development and provision of diverse, current instructional resources and that the Ministry of Education implement regular professional development programs for teachers to promote innovative teaching methodologies.

Customized Cyan Phosphors for Efficient Full-Spectrum Illumination and Fingerprint Detection.

Traditional lighting methods have environmental and efficiency drawbacks. These methods are gradually being overshadowed by light-emitting diodes (LEDs) because of their superior color rendering and energy efficiency. In this study, color-tunable NaBa2(Ba/Sr/Ca)Si2O7F:Eu2+ phosphors are successfully designed by modulating the local crystal field environment through homodominant-group cation substitution, thereby allowing for a spectral shift from blue to bright cyan. Detailed structural analysis of the samples demonstrated the synthesis of high-quality solid-solution materials. A comprehensive examination of the phosphor crystal structure, photoluminescence properties, and fluorescence lifetime reveal that the cyan phosphor possesses a remarkable internal quantum efficiency (IQE = 93%) and low thermal quenching characteristics (I423 K/I303 K = 84%). The results illustrate the critical role of Eu2+-activated cyan phosphors in reducing the spectral gap to attain a natural white-light spectrum, which is indispensable for achieving high color fidelity. The practical application of cyan phosphors in the fabrication of high-performance white LED (WLED) (Ra = 96.8) and fingerprint detection is validated, demonstrating their extensive utility in enhancing visual accuracy and identification.

Prevalence and Correlates of Cannabis Use among Cancer Survivors

Abstract Background Delaware has legalized marijuana use for both medical and recreational use. This study identified factors associated with cannabis use among adults with chronic relative to individuals without a history of cancer in the First State. Methods Combined data (2020, 2021 and 2022) from the Behavioral Risk Factor Surveillance System (BRFSS) were analyzed for Delaware. Multivariable logistic regression examined individual-level demographic, socio-economic, clinical, and behavioral predictors associated with marijuana use stratified by history of cancer. Results Cannabis use was lower among cancer survivors compared to individuals with no history of cancer (6.76% vs. 13.43%). However, a higher proportion of cancer survivors reported use for medical purposes (75.13% vs. 64.28%). Marijuana use prevalence decreased with age among cancer survivors. After adjusting for sex, age, educational attainment, self-reported race/ethnicity, mental health status and physical health status, current smoking (odds ratio [OR], 4.24 vs. 2.74) and binge drinking (OR, 2.45 vs. 1.75) were associated with cannabis use in both groups. Conclusions Adults with cancer were more likely to use marijuana. Marijuana use prevalence decreased with age. Public perceptions of marijuana is becoming more acceptable. Risk of medical conditions such as cancer increase with age. As such, older adults might also become consumers of marijuana. Clinicians should screen for marijuana use among patients and initiate open discussions with patients about the benefits and risks associated with marijuana. Key messages • Need for ongoing cannabis research to better understand and inform its use for medical purposes. • Development of high-quality standardized education materials and clinical practice guidelines for marijuana use.

Redefining Chronic Disease Care: Unleashing the Potential of Phytomedicines.

Phytomedicines represent a diverse array of plant-derived compounds renowned for their therapeutic potential. Traditionally, these mixtures were extracted using water or ethanol, but simpler methods like tea infusions are gaining prominence. However, ensuring the efficacy and safety of phytomedicines demands high-quality plant material and stringent production processes. Advancements in biological screening techniques have shed light on the mechanisms of action of phytomedicines, emphasizing the significance of synergistic interactions among their constituents. Ten widely-used phytomedicines are outlined, detailing their applications, efficacy, and safety profiles, underscoring their global importance in healthcare. Moreover, ongoing research in phytomedicine development showcases the rich biodiversity's capacity to yield novel medicinal compounds. These studies highlight the potential of untapped plant sources in providing innovative solutions to medical challenges, offering promising avenues for future therapeutics. In essence, the utilization of phytomedicines underscores a fusion of traditional knowledge with modern scientific approaches, emphasizing both the importance of respecting ancient remedies and harnessing contemporary advancements for improved healthcare outcomes.

Highly responsive gas sensors based on grain boundary–rich polycrystalline few-layer MoS2 films for NO2 detection

Abstract This study addresses the issues of insufficient sensitivity and poor reversibility for NO2 detection by successfully fabricating a sensor based on uniform and high-quality few-layer MoS2 polycrystalline material using chemical vapor deposition. This approach aims to improve the response of the sensor by exploiting the abundance of grain boundary (GB) defects in polycrystalline MoS2 membranes. Comprehensive surface morphology analysis of the few-layer MoS2 polycrystalline films was conducted using microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy to characterize their chemical composition and properties. Subsequently, evaluation of 1–100-ppm NO2 was conducted at room temperature (25°C). The results show excellent performance of the sensor, with a response range of 11–82.24. Notably, under ultraviolet excitation at room temperature, this sensor exhibits a response time of only 41 s to 50 ppm of NO2 with complete recovery and improved sensitivity, maintaining reliable stability over eight weeks. Furthermore, the findings reveal that the sensor demonstrates high selectivity toward NO2 gas with limit of detection and limit of qualification values of 10 and 34 ppb, respectively. Owing to the abundant adsorption sites provided by GB defects in polycrystalline thin films, the response performance of the sensor is effectively enhanced. This study provides valuable insights into the future design and development of high-performance NO2 gas sensors.

Natural radioactivity and technological properties of kaolinized granite from the Motajica mine, Bosnia and Herzegovina

For the production of ceramic tiles, it is necessary to use high-quality and economical raw materials, which will optimize the properties of the final product and meet the prescribed standards. For this reason, it is necessary to examine the properties of each potential raw material. This paper examines radioactivity and technological properties of kaolinized granite from the Motajica mine, in Bosnia and Herzegovina. Chemical analysis, X-ray diffraction (XRD), and thermal analysis (DTA) were carried out. In order to examine the technological (ceramic) properties of this raw material, ignition tests of the composite obtained by introducing kaolinized granite (with a content of 25 %) into the standard factory series of ceramic tiles were conducted at four selected temperatures (1050, 1100, 1120, and 1150 ℃). Total linear shrinkage, flexural strength, and water absorption were determined for the produced biscuit. Using gamma spectrometry, the activity concentrations of radionuclides 226Ra, 232Th and, 40K were measured, and then the radiation risk for external exposure of workers in the industry was assessed using hazard indices and doses. The radiation risk from the use of manufactured unglazed ceramic tiles in houses was also assessed. Statistical analysis of radionuclides for 100 samples of kaolinized granite was performed using descriptive statistics and hierarchical cluster analysis (HCA). It was observed that the average values of 226Ra, 232Th, and 40K are above the average for building materials in the world and amount respectively to 122 Bq kg−1, 96 Bq kg−1, and 1068 Bq kg−1. All other obtained values indicate that it is a quality raw material that, despite having an increased content of radioactive elements compared to the world average, does not represent a radiological hazard for workers and people who stay indoors on an annual basis. The tested raw material satisfies all technological criteria for further use and can be considered a desirable ingredient of ceramic composites because it can partially or completely replace feldspar.

Effects of Stretch-Bending Straightening on the Tensile Properties of Cold Rolled Packaging Steel

Achieving perfect flatness, tension-free surfaces, and exceptional resistance to spring back are important characteristics of packaging steel, setting the standard for high-quality material performance. To guarantee these crucial parameters, the implementation of the stretch-bending process at the final stage of the production route is indispensable. Besides improving the flatness properties, the induced plastic deformation results in an accompanying change in the mechanical properties. This investigation focuses on understanding this change in mechanical properties due to different stretch-bending straightening process parameters. A multivariate predictive model is created to calculate a process window for achieving the desired flatness and also mechanical properties in the production of packaging steel. This model is validated by experiments with a laboratory facility.

Efficient Preparation of Metal-Ion Intercalated Vanadium-Based Cathodes for High-Performance Aqueous Zinc-Ion Batteries: Na2V6O16·3H2O as an Example.

The inherent challenges associated with aqueous zinc ion batteries (AZIBs), such as low energy density and slow diffusion kinetics, pose significant obstacles to their widespread adoption as energy storage systems. These limitations mainly stem from the nongreen and complex preparation process of high-quality cathode materials. In this study, we propose an approach utilizing microwave-assisted ball milling to expedite the fabrication of vanadium-based intercalated nanomaterials, aiming at solving the problem of prolonged reaction at high temperatures, which is unavoidable in the preparation of anode materials. Na2V6O16 (NVO) nanorods were synthesized in just 40 min under aqueous solvent conditions. These nanorods exhibit remarkable electrochemical properties, including a high specific capacity of 564 mA h g-1 at 0.1 A g-1 and an excellent cycle life, maintaining 164.2 mA h g-1 after 5000 cycles at 5 A g-1. Additionally, the incorporation of Na+ into the electrolyte effectively mitigates the stripping of Na+ and the deposition of Zn dendrimers from NVO, further contributing to enhanced cycling stability. The findings of this study offer a promising approach to the rapid and efficient synthesis of high-quality ZIB cathode materials.

Influence of the Deformation of the Thread Section in the Direct Contact Zone on the Value of Acceleration of the Central Axis Points

Determined projections of the acceleration vector in relation to the arc length coordinate of the thread axis through components that define the degree of thread compression in the contact zone. Solving the challenges faced by the textile and light industries in increasing the production of fabrics and knitted goods based on improving the productivity of existing equipment and employing modern technologies, grounded in the latest scientific achievements, has significant economic and technical importance. The number of breakages can be significantly reduced by using high-quality raw materials and optimizing the conditions of thread processing on technological equipment, where interaction with guiding and working elements of large and small curvature occurs. Theoretical foundations for the accelerations of points on the thread axis, considering compression during its movement along a guide of large curvature, have been developed.

What’s Hot in Literacy: Misguided Trends in a Divided Field

ABSTRACT The annual What’s Hot in Literacy survey identifies current priorities in literacy education, highlighting the evolving landscape of the field. A panel of twenty-five literacy leaders participate in interviews to identify the most emphasized, least emphasized, and most deserving topics of increased attention. The 2024 findings highlight three topics as “extremely hot:” banned books, phonics/phonemic awareness, and the science of reading and structured literacy. There are also six topics found to be “very hot,” including artificial intelligence in literacy, cultural and linguistic diversity and literacy for multilingual learners, dyslexia and other specific learning disabilities, early literacy, high-quality instructional materials, and social justice/equity/anti-racism in literacy. Overall, the literacy field has received unprecedented focus this year, driven by legislative mandates in 38 states, policies on the science of reading, book banning, and discussions on essential early literacy skills for long-term academic and career success. This article examines the highlighted topics and the possibility that some of these are misguided trends. Additionally, it addresses the ongoing division within the literacy field, between advocates of content-focused and child-focused approaches to teaching and learning.

Using the Radial-Shear Rolling Method for Casted Zirconium Alloy Ingot Structure Improvement

In developing materials for the nuclear industry, it is crucial to enhance both alloy composition and processing methods. This study focuses on investigations of applying radial-shear rolling (RSR) to a Zr-1%Nb alloy ingot, aiming to refine its microstructure and improve its properties for nuclear applications. This method, with complex vortex metal flow inside of a casted workpiece, has not been previously tested for processing zirconium ingots, so experimental verification of its applicability is of scientific interest. The 30 mm diameter ingot, produced by vacuum induction melting, was initially rolled to 20 mm at 800 °C to eliminate defects and refine the cast structure. A second rolling stage reduced the diameter to 13 mm at 530 °C, resulting in an ultrafine-grained structure. The RSR method effectively combines structural refinement and defect healing within fewer cycles, making it suitable for producing components for nuclear reactors. This approach demonstrates a potential reduction in traditional processing steps, providing a more efficient route for preparing high-quality materials for nuclear applications.

Optimizing micropropagation of Miscanthus sinensis ‘Gold Bar’ by shortening the production cycle and reducing acclimation stress through the use of selected growth regulators

Miscanthus, with its decorative qualities and low cultivation requirements in terms of soil fertility and temperature, is the most popular grass in gardens and urban areas. For years, micropropagation has been regarded as an effective method of its production. However, in order to meet the demands of customers and provide adequate quantities of high-quality planting materials, it is necessary to develop more efficient methods of Miscanthus production. The present study evaluated the influence of different media on Miscanthus sinensis (Thunb.) Andersson (silver grass) multiplication as well as assessing the effect of different concentrations of selected cytokinins and auxins on multiplication and rhizogenesis. To shorten the production cycle and reduce costs, ex vitro rooting was combined with acclimatization, and selected growth regulators were used to decrease stress associated with external conditions. Biochemical analyses were conducted at each stage to determine the content of basic organic compounds, hydrogen peroxide (H2O2) and catalase activity. Stomatal function was assessed at the acclimatization stage. The obtained results allowed for the production cycle of plants propagated in tissue culture to be shortened by simultaneous rooting and acclimatization of microcuttings sprayed with abscisic acid (ABA). This regulator has been shown to effectively reduce plant stress associated with acclimatization by reducing H2O2 concentration and increasing assimilation pigment content. Growth regulators reduced the number of stomata that developed on the leaves of silver grass and led to lower stomatal conductance. H2O2 should be considered not only a stress marker but a vital signaling molecule.

Bipolar BINOL-PIM Cathode for High-Performance Aluminum Batteries.

Given the high abundance of aluminum in the Earth's crust, the development of aluminum-ion batteries can provide a cost-effective solution for large-scale energy storage. However, the key challenge in this field is to identify high-quality cathode materials that enable effective insertion/extraction of aluminum complex ions. In this regard, we present a strategy to prepare high-capacity, long-cycling aluminum-ion batteries aluminum-ion batteries (ALBs) cathode materials. High capacity was achieved by introducing multiple active sites into a 1,1'-bi-2-naphthol (BINOL) polymer of intrinsic microporosity cathode material to realize dual aluminum complex ion adsorption. The cathode had adjustable mesoporous structure that enabled its activation, wherein the pore size gradually increased during the insertion/extraction of aluminum complex ions, effectively enhancing battery capacity and cycling stability. The aluminum-ion battery cathode material achieved a high capacity of up to 110 mAh/g at a current density of 200 mA/g and could withstand over 3000 cycles at a high current density of 1 A/g. These findings provide a design approach for aluminum-battery cathode materials intended for low-cost, large-scale energy storage.

Macrolithic retouched blades from Kałdus and Stare Marzy: foreign technology and new ideology in the lithic traditions of the TRB communities in the Lower Vistula region

At the turn of the 20th and 21st century, over a dozen macrolithic retouched blades or their fragments were obtained from archaeological sites at Kałdus and Stare Marzy, located in the Lower Vistula region in northern Poland. The context of deposition links the blades to the settlements of the younger Funnel Beaker culture (3650/3500–3300/3100 BC). This article presents and discusses the results of morphological, technological, and raw material investigations of the macrolithic retouched blades or their fragments from Kałdus and Stare Marzy and relates them to the patterns of use and cultural significance of the macrolithic industry in the local TRB communities. The obtained results show that the retouched blades were made of high-quality flint materials sourced from the Polish and Ukrainian Uplands, namely Świeciechów, Volhynian and Jurassic flints. The results, furthermore, indicate that production technology of macrolithic retouched blades is very specific and, what is more important, it is not rooted in the lithic traditions of the region. Archaeological evidence from this study suggests exceptional patterns of use of macrolithic retouched blades in the Lower Vistula region and their perception by local TRB people, which can be traced to the Eneolithic milieu located southeast of the Polish Lowlands.

Development and effectiveness of short video tutorials in basic turning learning to enhance students' cognitive ability

This study aims to develop and evaluate the effectiveness of short tutorial videos in teaching the essential operation of lathe machines in mechanical engineering. Utilizing the ADDIE model (Analysis, Design, Development, Implementation, Evaluation), the research was conducted at SMK N 1 Sumatera Barat, involving 65 vocational school students. The short tutorial videos were designed to enhance students' comprehension and cognitive ability in lathe machine operations, addressing the challenges posed by traditional teaching methods. Data were collected through questionnaires and practical tests to assess students' understanding and skills. The findings revealed that the short tutorial videos significantly improved students' comprehension and cognitive ability, although variations in understanding levels were observed. Normality tests confirmed a normal data distribution, allowing for the use of paired sample t-tests, which indicated no significant difference between the Mechanical Engineering and Industrial Mechanical Engineering groups after using the tutorials. Validation by media and content experts demonstrated the high quality and relevance of the instructional material. This study underscores the importance of developing more interactive and adaptive learning media and highlights the need to explore further other factors influencing cognitive ability.

Features of the use of unmanned aircraft during the inspection of the scene of the incident during the investigation of violations of the road safety rules or vehicle operation

The article highlights the procedural and tactical features of the inspection of the scene of a traffic accident with the use of an unmanned aerial vehicle. To achieve this goal, the forensic features of conducting an inspection of the scene during the pretrial investigation of crimes of violations of road safety rules or vehicle operation at each of the preparatory, working, and final stages are revealed. The current state and prospects of the use of unmanned aerial vehicles by the bodies and units of the National Police during the inspection of the scene of a traffic accident were studied. The advantages of using an unmanned aerial vehicle during the inspection of the scene of a traffic accident are given, the concept of an unmanned aerial vehicle is defined, the methods and tactical methods of using an unmanned aerial vehicle. Scientific and practical recommendations are given on the procedure for recording crimes with the help of an unmanned aerial vehicle regarding violations of the rules of road traffic safety or vehicle operation during the inspection of the scene of the incident. It was concluded that the use of an unmanned aerial vehicle in the activity of the investigator during the investigation of traffic accidents is legitimate and provides much more advantages than the use of other methods of recording, such as measuring with a manual or laser tape measure, taking photos or video recording with cameras or video cameras. The use of UAVs during the inspection of the scene of the incident significantly reduces the time of its inspection, while providing the opportunity to obtain high-quality and sufficient evidentiary material.

Graphenic materials prepared from magnesium ions doping cellulose and its application in electrochemical detection of adenine and guanine

Graphenic materials of high quality are in high-demand. In this study, a method is proposed for the synthesis of graphenic materials by the pyrolysis of cellulose materials. Cellulose materials were oxidized and doped with magnesium prior to pyrolysis, which improved the graphitization efficiency significantly. The obtained graphenic materials, exhibiting a well-developed porous structure, high specific surface area, were employed for the fabrication of a composite electrode. The composite electrode was employed for the simultaneously detection of adenine (AE) and guanine (GA) with excellent performance in the electrocatalytic oxidation response. Various electrochemical tests were carried out to optimized the detection of AE and GA. Under the optimized conditions, the simultaneous quantification of GA and AE is achieved from 1 – 100 μM with detection limits from 0.4 – 0.6 μM. This study offers a promising alternative for the synthesis of graphenic materials of high quality.

Extremely Low Thermal Resistance of β-Ga2O3 MOSFETs by Co-integrated Design of Substrate Engineering and Device Packaging.

Gallium oxide (Ga2O3) emerges as a promising ultrawide bandgap semiconductor, which is expected to surpass the performance of current wide bandgap materials, like GaN and SiC, in electronic devices. However, widespread application of Ga2O3 is hindered by its extremely low thermal conductivity and lack of effective device-level thermal management strategies. In this work, Ga2O3 metal-oxide-semiconductor field-effect transistors (MOSFETs) are fabricated by conducting co-integrated design of substrate engineering with layer transferring and device packaging. 3D Raman thermography is introduced as a novel method to analyze the temperature distribution within the device, which provides valuable insights into their thermal performances. A high-quality Ga2O3-SiC heterogeneous integrated material is successfully fabricated with an extremely low interface thermal resistance of 6.67 ± 2 m2·K/GW. Compared to the homoepitaxial Ga2O3 MOSFETs, the degradation of Ion/Ioff in Ga2O3-SiC MOSFETs is decreased by 1.5 orders of magnitude, and that of Ron is decreased by 31%, showing the great thermal stability of Ga2O3-SiC MOSFETs. With the additional device packaging, a significant one order-of-magnitude reduction in the thermal resistance of the Ga2O3-SiC MOSFET is achieved, reaching a record-low value of 4.45 K·mm/W in the reported Ga2O3 MOSFETs. This work demonstrates an efficient strategy for device-level thermal management in next-generation Ga2O3 power and RF applications.