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Designing high-performance, wide bandwidth, lightweight, low-cost, and compact size absorbers for 5G anechoic chambers becomes essential. Several conventional absorbers, such as solid pyramidal absorbers, wedge absorbers, and convoluted absorbers, have shown acceptable absorption performance in a 5G mm-wave. However, these absorbers face challenges, such as narrow-angle of incidence, design complexity, and high cost. On the other hand, the hollow pyramidal absorber structures have a high level of freedom for optimization in order to be able to achieve the required specifications of 5G anechoic chambers. This paper provides an in-depth review of conventional absorber structures for use in anechoic chamber applications and their limitations for use in 5G applications, as well as the possibility of using hollow pyramidal absorbers in 5G anechoic chambers in comparison with conventional absorbers. [ABSTRACT FROM AUTHOR]

Understanding the changes in running mechanics caused by fatigue is essential to assess its impact on athletic performance. Changes in running biomechanics after constant speed conditions are well documented, but the adaptive responses after a maximal incremental test are unknown. We compared the spatiotemporal, joint kinematics, elastic mechanism, and external work parameters before and after a maximal incremental treadmill test. Eighteen recreational runners performed 2-minute runs at 8 km·h−1 before and after a maximal incremental test on a treadmill. Kinematics, elastic parameters, and external work were determined using the OpenCap and OpenSim software. We did not find differences in spatiotemporal parameters and elastic parameters (mechanical work, ankle, and knee motion range) between premaximal and postmaximal test conditions. After the maximal test, the runners flexed their hips more at contact time (19.4°–20.6°, P =.013) and presented a larger range of pelvis rotation at the frontal plane (10.3°–11.4°, P =.002). The fatigue applied in the test directly affects pelvic movements; however, it does not change the lower limb motion or the spatiotemporal and mechanical work parameters in recreational runners. A larger frontal plane motion of the pelvis deserves attention due to biomechanical risk factors associated with injuries. [ABSTRACT FROM AUTHOR]

This paper provides a comprehensive study of the impact of the gate recess depth (RD) on the GaN-on-Si MOS-HEMTs DC performances. IDS = f(VGS) and IDS = f(VDS) measurements are conducted at 25 and 150 °C, respectively, in forward and blocking modes. The gate recessed depth (50, 150, and 350 nm) is modulated by adjusting the plasma etching time, which is a critical step for improving the dielectric/GaN interface quality and the gate channel electron mobility. Three distinct regions can be defined separately: the bottom, the sidewall, and the corner region being the junction between the two previous regions. To assess the impact of gate recessed depth (RD) on the several mobilities around the gate cavity first, we applied our previous methodology allowing us to extract the bottom (μbot) and the entire sidewall region mobility (μT), without distinction from the corner. The mobility of the transverse region was found surprisingly to increase with deeper RD. To gain insight into the impact of the RD on this transverse section, a new extraction methodology is proposed to extract separately the gate corner (μcorner) and sidewall (μSW) mobility. These extractions show that the corner mobility is found to be reduced compared to the sidewall one (μcorner < μSW) evidencing the different weighting contributions over the transverse mobility. Moreover, these mobilities are found to be more degraded compared to the bottom one, highlighting the different contributions on the on-state resistance (RON). Indeed, the on-state resistance is lowered with the shallower RD due to the reduced sidewall resistance contribution (lower sidewall length) and despite the incremental contribution of the bottom resistance (larger effective gate length). However, the shallower RD shows an increase in the drain–source leakage current in reason of a lower gate electrostatic control. Technology Computer Aided Design (TCAD) simulations of the three RD morphologies are carried out to validate the experimental trends and the proposed methodology. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) are a new system that generates electricity and treats wastewater. The scientific community is interested in its applications; however, electron generation and transportation are key concerns. Thus, this research compares and studies common materials, which have never been widely investigated. The anode electrode is simple graphite (GE), mild steel (ME), and stainless steel (SE) to increase the transportation of electrons. Nypa fruticans Wurmb (Nira sap) is used as an easily available and highly beneficial organic substrate for bacterial populations. According to electrochemical tests, the GE offered 1.07 mW/m2 power density (PD), while the ME and SE delivered 2.75 mW/m2 and 5.85 mW/m2 within the first 35 days, respectively. The findings demonstrated that the SE anode had the highest specific capacitance values of 5.25 × 10−2 F/g, while the GE anode and ME anode had Cp values of 4.41 × 10−2 F/g, and 3.36 × 10−2 F/g, respectively. Bisphenol A (BPA) removal efficiency was maximum on the 65th day, with 96.25% for the SE anode, 94.55% for the ME, and 81.08% for the GE, while Pb2+ removal efficiency was 97.35% in the SE, 96.65% in the ME, and 96.60% in the GE. Bacillus sp. dominated all anodes during bacterial identification due to the same inoculation source. A comprehensive discussion of mechanisms is enclosed with future research directions. [ABSTRACT FROM AUTHOR]

Advancement in AI and deep learning has transformed medical image diagnosis; however, approaches to disease diagnosis, such as the detection of emphysema, one of the severest forms of COPD, stand to benefit from these technologies more. The main problem with the detection of emphysema from CT scans is the lack of very large, annotated datasets to train deep learning models. Classic models, like CNNs, are usually underfitting to small datasets and hence have very poor diagnostic accuracy. To address this challenge, we consider an integrated hybrid quantum–classical neural network model by combining the quantum variational circuits with CNNs. This new approach uses the power of quantum computing to identify subtle patterns in small datasets and could solve one of the key problems of deep learning. The model is pre-trained on large chest X-ray datasets and fine-tuned on a smaller emphysema dataset, which allows it to generalize more when data is limited. The experimental results confirm that the proposed approach is effective; namely, the quantum-assisted model reaches an accuracy of 0.5690 and F1-score of 0.5990, outperforming the traditional CNN models. This work points to the novelty of quantum computing in diagnosis with limited amounts of data, a very important challenge in this area of medical AI. Given that our research will conform to the limitation and work on small datasets, this work opens a new frontier in medical image analysis and shows ways in which QNN can substantially outperform traditional methods in detecting subtle markers of diseases; this indeed contributes to the growing body of knowledge in quantum-enhanced AI and opens up new frontiers toward some potential applications in the field of diagnosis of rare diseases and health diagnostics. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on the bark of E. kingiana plant afforded ten compounds, including six polyketides namely kingianin A 1, kingianin B 2, kingianin E 3, kingianin F 4, kingianin K 5 and kingianin L 6, three endiandric acids; kingianic acid A 7, tsangibeilin B 8 and endiandric acid M 9, and one sesquiterpene; daibuoxide 10. All compounds were separated as racemic mixture by recycling high-performance liquid chromatography (RHPLC), except for daibuoxide. Their structures were elucidated by detailed spectroscopic and comparative literature data analysis. This is the first report on the presence of the sesquiterpene; daibuoxide in Endiandra genus. In vitro enzymatic bio-evaluation of the isolated compounds against α-amylase and α-glucosidase showed that 4 demonstrated the best α-amylase and α-glucosidase inhibitory activity with IC50 values of 181.54 ± 6.27 µg/mL and 237.87 ± 0.07 µg/mL, respectively. In addition, molecular docking analysis confirmed the α-amylase and α-glucosidase inhibitory activities demonstrated by 4. [ABSTRACT FROM AUTHOR]

This study presents the computational behavior of precast lightweight foam concrete sandwich panel (PFLP) under flexural load and vibration using SAP2000. PLFP and other types of precast panels with various sustainable materials were proven to have a capacity at par with precast panel fabricated from conventional concrete. However, the number of studies on precast panel which focus on vibration are very limited. Thus, this study undertook the computational analysis on PLFP panel subjected to flexure load and vibration. Two PLFP panels from previous research, designated as PLFP-1 and PLFP-2, were modelled and simulated. The model of panel was first validated by comparing the deflection values of PLFP under flexure load, obtained from experiment and FEM. The validated models were then simulated against vibration and the natural frequencies obtained in each panel were recorded. It is found that PLFP-1 and PLFP-2 panels from FEM managed to obtain deflection significantly smaller than experiment which is 12.49mm and 18.44mm, respectively. The natural frequency recorded from the simulation against vibration are 18.9Hz and 19.32Hz, respectively. [ABSTRACT FROM AUTHOR]

In this study, a series of thiourea-substituted coumarin was synthesized in a four-step reaction from a precursor, 2-oxo-2H-chromene-3-carboxylic acid. The structures of all synthesized compounds were confirmed using NMR and LCMS. All synthesized compounds were screened for their antibacterial activity against gram-negative (Escherichia coli, Salmonella typhimurium, and Enterobacter aerogenes) and gram-positive (Staphylococcus aureus and Bacillus subtilis) bacteria strains using well diffusion method. Most of the synthesized compounds were found to be susceptible to most of the tested bacterial strains. The structure-activity relationship showed that compounds with substituents at the ortho position had lower overall activity as compared to meta-substituted and para-substituted compounds. Compound 19 was found to be the most effective antibacterial agent against gram-positive S. aureus and B. subtilis, with minimum inhibitory concentration values of 31.25 and 62.50 µg/mL, respectively. Molecular docking performed on potential compounds revealed significant binding site interaction with S. aureus gyrase residue Asp1083 and Met1121. [ABSTRACT FROM AUTHOR]

The issue of English language teaching among preschool teachers, without adequately considering the alternative approaches they have already implemented, necessitates exploratory research into their instructional practices. This qualitative study, employing a single case study design and purposive sampling of twelve preschool teachers, seeks to investigate the implementation practices and underlying rationales for English language teaching in Sarawak preschools. Data were collected through in-depth interviews, classroom observations, and document analysis at multiple preschool locations across the southern, central, and northern regions of Sarawak. Subsequent analysis using NVIVO 12 software revealed two primary themes that align with the study's objectives: (1) the implementation of English language teaching methods and (2) the use of English language learning strategies. To ensure the rigor and accuracy of the findings, the study used strategies for validity and reliability, including peer review, participant validation, audit trails, and triangulation. The implications of this research offer critical insights for relevant agencies in recognizing and understanding the realities of English language teaching practices and the beliefs held by preschool teachers in Sarawak. [ABSTRACT FROM AUTHOR]

Goal setting is a recognized technique for enhancing sports performance and athlete motivation by setting specific, measurable, attainable, relevant, and time-bound (SMART) goals. This study aimed to evaluate the effectiveness of a goal-setting intervention on the motivation and performance levels of handball players at Al-Amin Secondary School. A quasi-experimental design with pre-test and post-test control groups was employed, involving 30 players divided equally into treatment and control groups. The Goal Setting Questionnaire (GSQ) and Athlete's Subjective Performance Scale (ASPS) were used to measure motivation and performance, respectively. The independent samples t-test revealed that the treatment group, which participated in the goal-setting intervention, showed significantly higher motivation and performance levels compared to the control group during the mid-point test (p < 0.05). Paired samples t-tests further confirmed the intervention's effectiveness, showing significant improvements in both motivation (mean difference = -6.000, p < 0.001) and performance (mean difference = -29.133, p < 0.001) after six weeks. The findings align with existing literature, demonstrating that structured goal-setting interventions significantly enhance both motivation and performance in sports contexts. However, variability in the data suggests that individual differences and contextual factors play a crucial role in the effectiveness of these interventions. Future research should explore the long-term effects of goal setting and consider tailoring interventions to individual athlete needs to maximize their impact. This study highlights the potential of goal setting as a powerful tool for improving athletic outcomes in school sports programs. [ABSTRACT FROM AUTHOR]

This study investigates factors driving occupational fraud in the Maldivian public sector, from the perspective of external auditors. Using survey data from 59 auditors associated with the Auditor General's Office, it employs quantitative analysis, including regression modeling. Results indicate work-related pressure and employee denial of responsibility significantly influence fraud, with internal control effectiveness inversely linked to fraud occurrence. Financial pressure emerges as the primary fraud driver, surpassing work-related pressure. These findings offer crucial insights for policymakers, organizational leaders, and auditors, informing targeted strategies to prevent and detect fraud effectively, thus enhancing organizational resilience against fraudulent activities in Maldivian governmental entities. [ABSTRACT FROM AUTHOR]

This study examines secondary students' attitudes toward TVET. The public mindset of 3D illusions affects Malaysia's future aspirations for TVET. The purpose of this study is to understand why high school students do not value skills education as a means of improving their career prospects. A behavioral Insights approach was developed based on behavioral theories and social learning theory to identify environmental, social, and personal influences on student attitude. In this study, two phases were conducted- a survey and an experimental phase. The overall findings indicated that there was a low level of negative attitudes toward TVET. As a result of experimental testing, significant changes in attitudes towards TVET's curriculum & goals, as well as its roles, were discovered. The study results indicate that TVET literacy can reduce the negative mindset of TVET and encourage more after-school students to pursue TVET and join the pool of skilled workers. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to investigate the relationship between corporate tax avoidance and environmental, social and governance (ESG) performance and the moderating effect of financial constraints on the relationship between corporate tax avoidance and ESG performance. Design/methodology/approach: The sample consists of a global data set involving 24,259 firm-year observations from 49 countries for the years 2011–2020. Corporate ESG performance was extracted from the Thomson Reuters database. The book-tax difference model was used for measuring corporate tax avoidance, while financially constrained firms were identified using the Kaplan and Zingales (1997) index. Findings: The results show that firms with higher tax avoidance are associated with higher ESG performance, but lower ESG performance is shown for firms with higher financial constraints. The results further indicate that the positive impact of corporate tax avoidance on ESG performance becomes weaker for firms with higher financial constraints. Practical implications: The findings imply that policymakers and regulators should focus on mechanisms to promote more internal funds to assist firms in pursuing ESG-related initiatives, such as through tax incentives. Investors should understand the "smokescreen" effect of corporate tax avoidance on ESG performance, especially for firms with financial constraints. Originality/value: This analysis provides international evidence on the link between tax avoidance and ESG and considers the joint effect of pressures for internal funds, through tax and financing constraints, on corporate ESG performance. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSC) have developed rapidly since the past decade with the aim to produce highly efficient photovoltaic technology at a low cost. Recently, physical and chemical defects at the buried interface of PSC including vacancies, impurities, lattice strain, and voids are identified as the next formidable hurdle to the further advancement of the performance of devices. The presence of these defects has unfavorably impacted many optoelectronic properties in the PSC, such as band alignment, charge extraction/recombination dynamics, ion migration behavior, and hydrophobicity. Herein, a broad but critical discussion on various essential aspects related to defects at the buried interface is provided. In particular, the defects existing at the surface of the underlying charge transporting layer (CTL) and the bottom surface of the perovskite film are initially elaborated. In situ and ex situ characterization approaches adopted to unveil hidden defects are elucidated to determine their influence on the efficiency, operational stability, and photocurrent–voltage hysteresis of PSC. A myriad of innovative strategies including defect management in CTL, the introduction of passivation materials, strain engineering, and morphological control used to address defects are also systematically elucidated to catalyze the further development of more efficient, reliable, and commercially viable photovoltaic devices. [ABSTRACT FROM AUTHOR]

The enhancement of light absorption and surface area in monocrystalline solar cells is achieved through anisotropic etching, with the aim of improving its conversion efficiency. Nevertheless, the conventional method of anisotropic etching is constrained in its capacity for incrementing surface area. Herein, a promising texturization process in the form of a homogenous and uniform pyramidal structure is proposed with two-step texturing processes: cyclic voltammetry (CV) treatment and the alkali anisotropic etching method on the silicon wafer surface. Prior to and following the alkali texturing process, the silicon surface was modified using the CV treatment. The effect of this approach was investigated under different CV cycles (20, 40, 60 and 80 cycles) in a 0.5 M Na2SO4 aqueous electrolyte with pH ~ 7. Based on the field emission scanning electron microscope (FESEM) micrographs and UV-visible spectrometer (UV-Vis) measurements, the wafer textured with 60 cycles of CV treatment and an alkali anisotropic etching process tremendously improves the surface morphology and decreases the front surface reflection. As a result, the size and height of the pyramid formed were 2.1–2.3 µm and 0.6–1.9 µm, respectively. Moreover, the outlined methodology facilitates a substantial decrease in surface damage and is applicable in the Si texturization process for the manufacturing of solar cells. [ABSTRACT FROM AUTHOR]

Automated colour sorting, aided by mobile robots, is widely prevalent in the current manufacturing industry. Obstacles, such as fluctuating light conditions and camera angles, frequently hinder this procedure. Creating a colour sorting robot is a complex and time-consuming task, especially due to the vulnerability of the RGB colour space to detection errors in extreme brightness or darkness. In response to these concerns, we introduce a mobile robot that operates on the robot operating system (ROS) platform and incorporates OpenCV. This robot employs the hue, saturation, and value (HSV) colour space model for its image processing capabilities in recognising the colours and Welzl's algorithm for the ball's diameter estimation. The robot's performance was assessed across various luminous fluxes and camera tilt angles. It demonstrated exceptional performance at 64 lm and a tilt angle of 40 degrees, achieving an average accuracy of 87.5% for detecting the colour of the ball, and 81.25% for determining its location based on colour. For the ball's diameter estimation, it was found that the best estimation was received at 64 lm and 30 degrees, with both 96.32%. [ABSTRACT FROM AUTHOR]

Hospital plate waste poses a major challenge facing the present food systems, as providing meals that meet the nutritional requirements and expectations of the patients remains complex for hospital food services. This study aimed to assess the magnitude of plate waste in Lebanese hospitals, evaluate the patients' satisfaction levels, and identify the determinants of plate waste in participating hospitals. A cross-sectional study was conducted between April 2023 and September 2023, involving 155 in-patients from cardiovascular, gastrointestinal, obstetrics-gynecology, and surgical wards across 16 hospitals in different Lebanese governorates. Plate waste was measured, and patient satisfaction was assessed using a questionnaire. Plate waste represented 31.4% of the total food served, equivalent to 366 tonnes annually in the 16 participating hospitals. Waste was higher in hospitals located in rural areas (p-value = 0.771). The highest waste levels were observed in the obstetrics-gynecology ward and during lunchtime. Vegetables were the most wasted food group. The majority of participants were satisfied with the food service, and low appetite was the main reason for not consuming hospital meals. Food quality (β= −0.17, p-value = 0.049) and governorate (β= −0.18, p-value = 0.019) were determinants of plate waste. The hospital sector is as unique and challenging as other sectors regarding plate waste, which warrants further research to gain deeper insights into waste generation. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation is a key technique in wastewater treatment, particularly for toxic dye removal, yet challenges related to poor hydrodynamics and mass transfer limitations persist. This study addresses these challenges by innovatively employing an adjustable-angle baffle in a plug flow reactor (PFR) to enhance dye removal efficiency. A lab-scale PFR with an adjustable baffle was utilised to assess the impact of various factors, including baffle angle, catalyst concentration, hydraulic retention time (HRT), pH, and initial dye concentration, on the removal of direct red 23 dye. The experimental design employed a central composite design (CCD), with subsequent data analysis using response surface methodology (RSM) and artificial neural network (ANN) models. The findings demonstrate that the adjustable baffle significantly impacts dye removal, achieving maximum efficiency at an optimal angle of 77.5 degrees. The ANN model outperformed the RSM model, with a higher determination coefficient (R2) of 0.994 compared to 0.928. Furthermore, RSM and genetic algorithms yielded closely aligned optimal conditions, validating their accuracy. The optimised conditions achieved a dye removal efficiency of 89.47%. Significantly, the study also identified degradation as the dominant mechanism over adsorption and highlighted the impressive stability of nano-Fe3O4 during the recycling process. Mineralisation analysis revealed the presence of lightweight organic residual molecules post-treatment. These outcomes demonstrate the effectiveness of adjustable baffles in PFRs, marking a significant advancement in wastewater treatment technologies and underscoring the critical role of baffle orientation and catalyst concentration in optimising dye removal processes. [ABSTRACT FROM AUTHOR]

Life cycle assessment (LCA) is a methodology used to analyze the environmental impacts of a product. Initially, it was applied to buildings only, but recently, it has also been applied to entire neighborhood. This expansion from individual buildings to the neighborhood scale requires additional inputs, such as the impacts of public spaces, transportation, public network systems, and roads. Additionally, conducting an LCA for a neighborhood requires software tools to simulate the neighborhood and databases to store the environmental impacts of all the components integrated into the neighborhood. This paper presents an LCA case study of a neighborhood in Dijon, France. The study aims to analyze the thermal impacts of buildings and the neighborhood with single-, double-, and triple-pane windows. The second part of the study involves two LCA studies using the 1996 version of ecoinvent. The first study is a continuation of the thermal simulation analysis, while the second study compares concrete, masonry, and timber-based construction designs for the neighborhoods. The results show that the heating demands inside the buildings are substantially reduced when transitioning from single- to triple-pane, while the cooling demands show the opposite effect. Furthermore, doubling the width of double-pane windows resulted in less profound environmental damage for the construction, use, and demolition phases compared to single-pane windows, with only the renovation phase being more damaging. Additionally, the comparison between different construction scenarios shows that the timber-based variant is slightly advantageous from an environmental point of view compared to the concrete and masonry designs. [ABSTRACT FROM AUTHOR]

Background: Gold ormus is a type of superconductor that can exhibit superconductivity at temperatures below 1 Kelvin, allowing it to conduct electricity without resistance. While not as widely used as other materials like niobium or lead, gold ormus is valuable for research in superconductivity. Limited studies have been conducted on gold ormus. Numerical simulations of the Ginzburg–Landau theory have yielded important results for both gold ormus. Results: Class-I and class-II superconducting gold ormus, have been successfully simulated using the Runge–Kutta fourth-order method. Our analysis shows the convergence of our simulation outcomes and emphasizes the importance of considering truncation error and selecting appropriate step sizes for accurate results. The periodic factor of penetration (PFP) for each superconductor has been determined, with class-I superconducting gold ormus having a PFP of 250 nm, class-II superconducting gold ormus having a PFP of 566.2 nm. The relationship between the PFP and the length of the penetration depth has also been revealed. Conclusions: Our study confirms the accuracy of the Runge–Kutta fourth-order method in simulating superconductors. By analyzing the PFP for different superconducting materials, we have identified trends in penetration depth that contribute to understanding superconductivity. Our simulations provide valuable insights for further research in the field of superconductivity. Adjusting parameters carefully ensures reliable simulations and advances progress in superconductivity research. [ABSTRACT FROM AUTHOR]

Grading of oil palm fresh fruit bunches (FFB) plays a vital role in the postharvest operation as it directly influences the extraction rate of oil palm, thereby ensuring quality control in the estate and mill. Currently, manual grading based on visual assessment is employed, but it has limitations mainly due to subjective judgment-influenced factors such as visual resemblance, light intensities, and differences in colors across ripeness categories. Hence, an automated oil palm fruit grading system in postharvest technology is proposed to enhance the grading process and improve productivity while maintaining operational cost efficiency. This work involves developing an improved object detection model based on the You Only Look Once model to accurately identify four grades of oil palm FFB, namely, ripe, unripe, underripe, and overripe. The proposed model incorporated several improvements, including a hybrid feature extractor comprising mobile inverted bottleneck module and densely connected neural network. Additionally, it employs a spatial pyramid pooling structure to expand the receptive field and utilizes the complete intersection over union function for bounding box regression. The results indicate that the proposed model obtains a remarkable mAP of 94.37% and an F1-score of 0.89. Besides, the model performs real-time detection at a faster rate of 4.8 FPS on a limited-capacity embedded device, NVIDIA Jetson Nano. The comprehensive experimental results confirm the superiority of the proposed model over various detection models. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) technology is a promising strategy that can directly convert sunlight into chemical energy. Direct solar water splitting through the PEC process is a desirable method for green hydrogen (H2) production. This technology has also the potential to capture CO2 and convert it into fuels using sunlight and water, besides converting N2 and H2O to produce ammonia (NH3), which acts as transportable H2 storage. The cracking of NH3 to produce H2 can also be accomplished using PEC technology. Despite improved PEC performance having been shown, stability, efficiency, and scalability issues still need to be resolved. Even so, PEC technology has much potential as a clean and sustainable solution for addressing global energy and environmental challenges. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to investigate the effect of different beam distance by understanding laser beam influence on solder joint quality. The utilisation numerical-based simulations and experimental validation will help to minimise the formation of micro void in PTH that can lead to cracks and defects on passive devices. Design/methodology/approach: The research uses a combination approach of numerical-based simulation using Finite Volume Method (FVM) and experimental validation to explore the impact of different laser beam distances on solder joint quality in PTH assemblies. The study visualises solder flow and identifies the optimal beam distance for placing a soldering workpiece and a suitable tolerance distance for inserting the solder wire. Findings: The simulation results show the formation of micro void that occurs in PTH region with low volume fraction and unbalance heat concentration profile observed. The experimental results indicate that the focus point of the laser beam at a 99.0 mm distance yields the smallest beam size. Simulation visualisation demonstrates that the laser beam's converging area at +4.6 mm from the focus point which provides optimal tolerance distances for placing the solder wire. The high-power laser diode exhibits maximum tolerance distance at 103.6 mm from the focus point where suitable beam distance for positioning of the soldering workpiece with 50% laser power. The simulation results align with the IPC-A-610 standard, ensuring optimal filling height, fillet shape with a 90° contact angle and defect-free. Practical implications: This research provides implications for the industry by demonstrating the capability of the simulation approach to produce high-quality solder joints. The parameters, such as beam distance and power levels, offer practical guidelines for improving laser soldering processes in the manufacturing industry. Originality/value: This study contributes to the field by combining high-power laser diode technology with numerical-based simulations to optimise the beam distance parameters for minimising micro void formation in the PTH region. [ABSTRACT FROM AUTHOR]

Incorporation of chromium (Cr) nanoparticle onto LaFeO3 (LFO) photocathode to improve optical and photocatalytic activities have been successfully demonstrated. The plain LFO photocathode was prepared by spin-spray gun deposition, following the Cr-incorporated nanoparticle onto the photocathode by spin coating method. It is observed that the photocathode with the optimal composition of 1.5 mmol Cr nanoparticle enhanced the crystal growth of orthorhombic crystal structure predominantly on (121) orientation with the formation of well-connected crystal grain architecture. The structure demonstrated strong optical absorption and a high current density of -60.52 µA cm− 2 at -0.5 V (vs. Ag/AgCl) more than twice to the untreated LFO film which recorded a maximum photocurrent of -21.83 µA cm− 2 at -0.5 V (vs. Ag/AgCl). This subsequently led to suppressed surface recombination, lower charge resistance and good stability in the strong alkaline electrolyte. The enhancement provided that incorporating a transition metal element with plain LFO would be applicable for producing efficient photosensitive devices, particularly for photoelectrochemical (PEC) water splitting applications. [ABSTRACT FROM AUTHOR]

The conformational space of cis-1,2-cyclohexanediol, a model molecule for cyclic vicinal diols, was investigated using rotational spectroscopy and density functional theory calculations. Four low energy conformers within an energy window of 5 kJ mol−1 were identified computationally. A rotational spectrum of jet-cooled cis-1,2-cyclohexanediol was recorded with a chirped pulse Fourier transform microwave spectrometer. Two sets of rotational transitions were observed and could be assigned to conformers of cis-1,2-cyclohexanediol. The non-observation of other low energy conformers was explained by conformational conversion barrier height calculations and results from experimental spectra recorded with different carrier gases. Eight isotopologues, including those with 13C and 18O, of the lowest energy conformer were observed, allowing the determination of the semi-experimental equilibrium structure, reSE. Interestingly, the structural analysis revealed that the C–O bond length of the intramolecular hydrogen-bond donor is shorter than that of the acceptor. This appears to be a general characteristic of vicinal diols and can be used as a novel hydrogen-bond marker in such compounds. [ABSTRACT FROM AUTHOR]