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Glutaryl kappa-carrageenan: synthesis, characterization and investigation of potential as gel-based biopolymer electrolyte
No full textA novel kappa-carrageenan derivative, glutaryl kappa-carrageenan (G-κCar) was successfully produced via nucleophilic substitution reaction. The introduction of glutaric anhydride (GA) into the kappa-carrageenan (κCar) matrix had markedly altered its chemical and electrochemical properties. Elemental analysis showed that the GA substitution led to an increased oxygen percentage in G-κCar as compared to pure κCar. The highest degree of substitution obtained was 4.14 in 3 gGA-κCar/48 h synthesized sample. The successful substitution of GA molecule into κCar polymeric chain was confirmed by the FTIR analysis based on the formation of a new carbonyl (C=O) bond in the G-κCar spectra. The 1H-NMR analysis further proved the GA substitution by the appearance of new multiple resonance peaks at δ = 1.70–2.75 ppm, which belonged to the characteristic signals of protons in the anhydride group. TGA thermograms showed lower degradation temperature in the synthesized G-κCar due to disruption of both intermolecular and intramolecular hydrogen bonds in the G-κCar polymeric chains. The substitution of GA also improved the ionic conductivity of G-κCar up to 4.63 × 10−3 S cm−1 at ambient temperature. Cyclic voltammetry plots demonstrated that the 3 gGA-κCar/48 h sample had a larger background current than κCar which indicated that the synthesized 3 gGA-κCar/48 h biopolymer had an improved effective surface area. Linear sweep voltammetry (LSV) analysis revealed the increased electrochemical potential in G-κCar as compared to the pristine κCar. The highest potential obtained was 1.95 V for 3 gGA-κCar/48 h sample. The transference number for 3 gGA-κCar/48 h was calculated to be 0.98 over five continuous hours. This implied that ionic conduction in the gel was predominantly driven by ions, with the contribution of electrons being minimal and therefore negligible. This study highlighted how this functionalization enhanced the characteristics of κCar, potentially expanding G-κCar applications as a gel biopolymer electrolyte in electrochemical systems
Remote onboarding and beyond: Fostering organizational citizenship behavior through psychological channels
Full text linkAim/purpose – The purpose of this paper is to investigate the influence of remote onboarding practices on organizational citizenship behavior. This study addresses the gap in understanding how remote onboarding influences employees’ behavior through psychological processes. Design/methodology/approach – The study utilizes a quantitative research approach, analyzing data collected from 608 respondents through structured surveys. It employs a serial mediation process to explore the roles of psychological contracts and psychological ownership in the relationship between remote onboarding and organizational citizenship behavior. Findings – The study reveals that remote onboarding programs have a significant impact on organizational citizenship behavior by fostering a psychological contract and psychological ownership. These factors act as mediators, linking effective onboarding practices to enhanced employee organizational citizenship behavior. Research implications/limitations – The findings provide valuable insights into management practices, highlighting the importance of prioritizing comprehensive digital onboarding strategies for organizations. However, the study’s reliance on self-reported data may introduce biases, and future research should consider conducting longitudinal studies to validate the results. Originality/value/contribution – This research contributes to the existing literature on social exchange theory and social identity theory by elucidating the psychological mechanisms that connect remote onboarding to organizational citizenship behavior. It offers practical recommendations for enhancing digital onboarding processes to promote employee engagement and improve organizational outcomes
Quantitative evaluation and optimization of carbon sequestration in Chongqing’s parks under the ‘dual carbon’ strategy
Full text linkTo quickly and efficiently evaluate the carbon sequestration benefits of urban parks, a quantitative evaluation method for carbon sequestration is designed taking sponge city parks as an example. The correlation between the average diameter at breast height of plants and the net primary productivity of vegetation was the strongest. Through optimized design, urban parks can better integrate the positive and negative benefits of sponge facilities, effectively enhancing their carbon sink capacity. At the same time, by promoting and applying the construction concepts and technical means of sponge-type parks, the study is expected to form more green spaces within the city
Study of deposit accumulation and tribological degradation in diesel engine utilizing blend fuels
Full text linkUtilizing alcohol in diesel engines offers an alternative approach to reducing dependence on diesel fuel. Specifically, higher alcohols such as n-butanol (nB) and n-pentanol (Pn), which have high carbon content and are largely derived from non-edible sources, can be directly blended with diesel. These blends present significant economic and environmental advantages, making the study of high-carbon alcohol use in diesel engines increasingly important. This research focused on creating blends of waste cooking oil and n-pentanol with diesel fuel, preparing three binary and ternary mixtures: DF95WCO5 and DF65WCO20Pe20. The primary goal was to investigate the fundamental characteristics of these blends. However, challenges such as increased deposits, pollutant emissions, and reduced engine performance when using biodiesel have been noted. A detailed evaluation of combustion chamber deposit buildup and its impact on emissions and engine performance was carried out. The study employed diesel, waste frying oil, and n-pentanol blends. After 200 h of operation, engine injectors and pump pistons were examined using scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis. It was discovered that waste cooking oil binary mix fuel had a greater rate of carbon deposition generation than diesel fuel, with 89.68% for WCO and 80.01% for D100. By contrast, engine part deposition was reduced when n-pentanol was mixed with waste cooking oil as opposed to diesel fuel, with a deposition rate of 47.90% for n-pentanol. The results revealed notable surface structure changes on pistons with DF95WCO5 and n-pentanol blends. Wear debris concentration was reduced when using emulsified fuels, particularly in binary blends, while the ternary blend DF65WCO20Pe20 showed further reductions in Cadmium (Cd), Iron (Fe), Copper (Cu), and Nickel (Ni) compared to pure diesel. The engine demonstrated lower viscosity and increased density when operated with these blended fuels. Experimental findings highlighted significant differences between biodiesel derived from used and fresh cooking oils, including reduced engine performance, higher carbon deposits, and accelerated metal degradation in key components of diesel engine lubricating oil
AC susceptibility and electrical properties of Ag2S added Bi1.6Pb0.4Sr2CaCu2O8 superconductor
No full textBi1.6Pb0.4Sr2CaCu2O8 (Bi-2212) superconductor samples doped with silver sulfide (Ag2S) in different weight percentages (x = 0, 0.1, 0.2, 0.4, 0.5, and 1.0 wt.%) were synthesized by the solid-state reaction method. X-ray diffraction (XRD) analysis revealed that all the samples contained Bi-2212 as the dominant phase. The electrical resistance versus temperature curves showed metallic normal state behavior for samples with 0 ≤ x ≤ 0.4 while the sample with x = 0.5 wt. % and x = 1.0 wt. % showed a semimetal-like normal state behavior with an onset transition temperature, Tc onset between 82 and 96 K and zero transition temperature, Tc zero between 65 and 77 K. AC susceptibility curves showed that the susceptibility transition temperature, Tcχ’ was between 76 and 83 K for all samples. The intergrain critical current density, Jc at the peak temperature, Tp of the imaginary part of the susceptibility c” for all samples was between 16 and 19 A⋅cm− 2. The x = 0.1 wt% sample showed the highest Tp, (65 K), indicating an improvement in the flux pinning strength. The highest maximum intergrain Josephson current, I0 and Josephson energy, Ej were between 11.12 and 14.41 µA and 23.02–29.60 meV, respectively for x = 0.5 and 1.0 wt% samples. This work demonstrated that a lower amount of Ag2S improved the flux pinning energy of the Bi-2212 phase while a higher amount of Ag2S enhanced intergrain coupling
Gratitude (shukr) group intervention for promoting college students’ well-being: a quasi-experimental study
Full text linkThis study examined the impact of a gratitude (shukr) group intervention on the well-being of college students. We hypothesised that participation in the intervention would increase feelings of well-being. A single-group quasi-experimental design with pre-test and post-test measures was employed. A convenience sample of 95 s-year college students consented to participate—the intervention, conducted over four weeks between November and December 2023, involved weekly gratitude group sessions. The Warwick-Edinburgh Mental Well-being Scale (WEMWBS) was used to assess well-being before and after the intervention. Descriptive statistics and paired sample t-tests were conducted to analyse the data. Qualitative data from participants' reflection reports were also thematically analysed for supportive evidence. Results indicated that post-test well-being scores were significantly higher than pre-test scores (p < .05). The findings suggest that the gratitude (shukr) group intervention significantly improved college students’ well-being
From fear to facts: a multi-channel approach to information seeking amid influenza-like illness outbreaks
Full text linkBackground: During recurrent large-scale influenza-like illness (ILI) crises, the factors influencing the information-seeking intentions of Chinese individuals across multiple channels during crises remain underexplored. Objective: Guided by the risk information seeking and processing (RISP) model, this study proposes a modified RISP model to comprehensively analyze information-seeking intentions through the lens of risk communication. Methods: To empirically validate the proposed research model, we conducted an online cross-sectional survey with 2,604 Chinese citizens aged 18 years and older. Structural equation modeling (SEM) and ordinary least squares regression analysis were employed to analyze the survey data. Results: Our findings revealed that during ILI crises, Chinese individuals experienced a spectrum of emotions; as perceived risk increased, negative emotions intensified while positive emotions decreased. Increased negative emotions correlated with a greater sense of information insufficiency, whereas heightened positive emotions correlated with a reduced perception of it. Consequently, Chinese individuals facing information deficiencies were more inclined to seek information from diverse sources, including interpersonal sources, traditional media, search engines, and social media. Moreover, statistical analysis indicated that stronger beliefs in channel complementary strengthened the relationship between information insufficiency and information-seeking intention across multiple channels (access to medical expertise belief, tailorability belief, convenience belief, anonymity belief). Conclusion: This study outlines a pathway for advancing the RISP model and offers practical strategies for effective risk communication to mitigate risks and enhance public perception and behavior. It also discusses implications for health communication, promotion, and behavior change
Optimization of soaking conditions in parboiling using response surface methodology to enhance the properties of MR297 rice cultivar
Full text linkMR297 is known as a resistant cultivar to rustic disease but has a low head rice yield. The purpose of this study was to optimize the soaking conditions (temperature and time) for the enhancement of quality characteristics of long grain rice cultivar MR297 parboiled The experiment was done by optimizing the effects of soaking temperature (50–70 °C) and soaking time (2–4 h) for paddy using a central composite design of response surface methodology. The parboiling process then continued with steaming 100 °C for 20 min and drying 38 °C for 24 h). Besides analyzing the physical properties and milling properties of parboiled rice, the color and hardness properties of parboiled milled rice varieties were also investigated. We used design expert software to optimize the responses numerically. MR297 parboiled rice quality was significantly affected by the temperature and soaking time (p < 0.05). It was found that 54.75 °C and 2 h of soaking was the optimal temperature and time. The optimization was done to maximize the head rice yield, maximize the hardness, maximize the lightness, and also minimizing the browning index and total color change of the milled rice during parboiling, the proposed suggestion should be implemented
Adjusted exponential scaling: an innovative approach for combining diverse multiclass classifications
Full text linkEnsemble learning plays a crucial role in deep learning (DL) by improving classification accuracy through the aggregation of multiple classifiers. However, traditional methods, such as bagging, boosting, and stacking, face limitations when combining heterogeneous classifiers trained on unrelated tasks, owing to their reliance on closely aligned objectives. To address these challenges, we propose Adjusted Exponential Scaling (AES), a novel approach that combines diverse classifiers using probabilistic outputs, such as those generated by the Softmax function. AES eliminates the need to modify DL architectures or interfere with their training processes, thereby significantly reducing computational costs while ensuring compatibility with existing systems. We demonstrate AES scalability in simulations, successfully combining the outputs of up to 40 classifiers while maintaining probabilistic integrity. A formal verification using the Z3 Satisfiability Modulo Theories (SMT) solver confirmed its accuracy and reliability. AES is designed for simplicity and adaptability, making it particularly well suited for dynamic applications such as deepfake detection and medical diagnostics, where real-time combination is critical. By providing a scalable and computationally efficient solution, AES expands the applicability of ensemble learning and establishes a foundation for future extensions to sequential and binary tasks, further enhancing its versatility in machine learning challenges
Transformer-LSTM models for automatic scoring and feedback in English writing assessment
Full text linkWriting assessment is one of the most important stages in the educational process, but it is also the most resource-demanding one. To address the challenges of scalability and inconsistency, this study proposes a Transformer-LSTM model for automated scoring and feedback generation, enhancing accuracy and reliability in assessment. Integrating the contextual reading abilities of transformers with the sequential analysis strength of LSTMs, the model analyzes significant metrics of writing quality, including grammar, coherence, and structure, while providing individualized, actionable feedback. Using annotated datasets and evaluation metrics like RMSE and feedback relevance, it was established that the model performs well overall and that improvements in grammar and coherence seemed to be the most significant contributors to writing ability. It was also demonstrated that feedback relevance enhances these outcomes, thus confirming its valuable role in promoting structural and grammatical accuracy. Understanding that most existing systems do not encourage significant human feedback, this work demonstrates a scalable approach with potential alignment with human evaluation standards. Finally, this study shows hybrid models’ promise for automated writing assessment as promising scalable, equitable, impact-based tools for global enhancement of educational outcomes