bluuebunny/crossref_metadata_2025 huggingface dataset:
Advances in Flame Retardant Technologies for Epoxy Resins: Chemical Grafting onto Carbon Fiber Techniques, Reactive Agents, and Applications in Composite Materials
Authors: Dagdag Omar , Kim Hansang
Published: December 2024

This review examines recent advancements in flame retardant technologies for epoxy and bio-epoxy resins, focusing on the chemical grafting of hexachlorocyclotriphosphazene (HCCP) onto carbon fibers (CFs) and the use of reactive flame retardant agents in composite materials. It covers various grafting techniques and analyzes mechanisms behind property enhancements, exploring how these approaches improve thermal stability and flame resistance while addressing sustainability challenges. This review discusses the synergistic effects of bio-based materials and innovative grafting methods. It presents applications of flame-retardant epoxy–carbon fiber composites, demonstrating the potential of HCCP-CF composites as high-performance, environmentally friendly structural materials. Additionally, this review evaluates the impact on mechanical properties and interfacial bonding, crucial aspects often affected by flame retardant treatments. This comprehensive overview provides valuable insights, identifying current challenges, future directions, and potential breakthroughs in the field of advanced composite materials.
Structural and Physicochemical Properties of Glycerol-Plasticized Edible Films Made from Pea Protein-Based Emulsions Containing Increasing Concentrations of Candelilla Wax or Oleic Acid
Authors: Kowalczyk Dariusz , Kazimierczak Waldemar , Zięba Emil , Lis Magdalena , Wawrzkiewicz Monika
Published: December 2024

Hydrophobization could improve the moisture resistance of biopolymer-based materials, depending on the methods and materials used, providing benefits for packaging applications. The aim of this study was to compare the effect of increasing concentrations (0–2.0%) of candelilla wax (CW) and oleic acid (OA) on the structural and physicochemical properties, including water affinity, of glycerol-plasticized pea protein isolate (PPI) films. OA acidified the film-forming solution and increased its viscosity more effectively than CW. At the highest concentration, OA prevented cohesive film formation, indicating a weakening of protein self-interaction. OA caused less yellowing, matting, and a smaller reduction in UV/VIS light transmittance compared to CW. Both lipids caused a slight reduction in the films’ water content. Phase separation (creaming) of CW enhanced surface hydrophobicity, resulting in a greater reduction in water vapor permeability than OA (~37–63% vs. 2–18%). The addition of lipids did not reduce film solubility or water absorption, and OA even increased these parameters. Increasing lipid content decreased the mechanical strength and stretchability of the films by 28–37% and 18–43%, respectively. The control film exhibited low heat-sealing strength (0.069 N/mm), which improved by 42% and 52% with the addition of CW and OA at optimal levels.
Effect of a Steaming Treatment on the Alpha-Glucosidase Inhibitory Components in the Brown Alga Sargassum fusiforme
Authors: Liu Xinxin , Gu Yipeng , Zhou Yihao , Zhang Ruiqi , Koyama Tomoyuki
Published: December 2024

The brown alga Sargassum fusiforme (SF) is historically consumed as a food material in Japan. A steaming process is often required for SF products on the market due to their moderate hardness and astringent taste. This investigation aimed to elucidate the effect of steaming on the anti-diabetic activity of SF and its related chemical components. Acetone extracts of SF were prepared after it were steamed for 0, 1, 2, or 4 h (SF-0h, SF-1h, SF-3h, and SF-4h, respectively). Alpha-glucosidase inhibitory profiles of each SF extract were made based on activity-guided separation. The active fractions were collected and NMR was applied for a further chemical composition analysis. Our results suggested that total polyphenol levels decreased drastically after steaming, which resulted in a drop in α-glucosidase inhibitory activity. The fatty acid, pheophytin a, and pyropheophytin a contents were elevated significantly after steaming, which contributed to the majority of the activity of steamed SF (SF-1h). However, prolonging the steaming time did not significantly affect the activity of SF further since the content of free fatty acids in steamed SF (SF-2h and SF-4h) almost did not change with a longer time of steaming. Moreover, palmitic acid, 8-octadecenoic acid, and tetradecanoic acid were identified as the top three important fatty acids for the inhibition of α-glucosidase by steamed SF. Further molecular docking results revealed that these fatty acids could interact with residues of α-glucosidase via hydrogen bonds, salt bridges, and hydrophobic interactions. In conclusion, steaming altered the α-glucosidase inhibitory properties of SF by changing the contents of polyphenols, fatty acids, and chlorophyll derivatives.
Dynamic Neuro-Glial-Vascular Responses in a Mouse Model of Vascular Cognitive Impairment
Authors: Kim Ki Jung , Patterson Rachel E. , Diaz Juan Ramiro , O’Herron Philip , Bush Weston , Althammer Ferdinand , Stern Javier E. , Brands Michael W. , Bagi Zsolt , Filosa Jessica A.
Published: December 2024

Background: Chronic hypoperfusion is a risk factor for neurodegenerative diseases. However, the sequence of events driving ischemia-induced functional changes in a cell-specific manner is unclear. Methods: To address this gap in knowledge, we used the bilateral common carotid artery stenosis (BCAS) mouse model, and evaluated progressive functional changes to neurons, arterioles, astrocytes, and microglial cells at 14 and 28 days post-BCAS surgery. To assess the neuro-glio-vascular response to an acute ischemic insult, brain slices were superfused with low O2 conditions. Using whole-cell patch-clamp electrophysiology, we measured basic membrane properties (e.g., resting membrane potential, capacitance, input resistance) in cortical pyramidal neurons. The activity of astrocytes was evaluated by monitoring Ca2+ from Aldh1l1-CreERT2; R26-lsl-GCaMP6f mice. Vascular reactivity to low O2 from the BCAS mice was also assessed ex vivo. Results: Our data showed no changes to the basic membrane properties of cortical pyramidal neurons. On the other hand, astrocyte activity was characterized by a progressive increase in the resting Ca2+. Notably, at 14 and 28 days post-BCAS, there was an increased expression of anti-inflammatory-related markers (IL-10, S100A10, TRPA1, and Nrf2). These data suggest that, in young mice, BCAS-induced increases in resting Ca2+ were associated with the expression of neuroprotective signals. Contrary to observations in glial cells, vascular function was impaired post-BCAS surgery, as shown by a blunted vasodilatory response to low O2 and the vasodilatory signal, adenosine. Conclusions: Together, these data suggest that, in young mice, BCAS leads to vascular dysfunction (e.g., impaired vasodilation in parenchymal arterioles), and in the absence of neuronal dysfunction, mild ischemia is associated with the activation of glial-derived neuroprotective signals.
The Prevalence of Behavioral and Emotional Problems and Their Associated Factors Among Children and Adolescents in Jordan: Findings from a National School-Based Survey
Authors: Labib Bayan , Khader Yousef , Abu Khudair Sara , Al Nsour Mohannad , Tanaka Eizaburo
Published: December 2024

Background: Global research has reported that the number of children and adolescents suffering from mental health issues has increased over the past decades. In Jordan, there has been a growing interest in investigating mental health among these groups in the most recent decade; nevertheless, only a few studies have covered behavioral and emotional problems. This study aimed to estimate the prevalence of behavioral and emotional problems among children and adolescents in Jordan and investigate their associated factors. Methods: A large-scale, national, school-based cross-sectional study was conducted between December 2022 and April 2023 on children and adolescents living in Jordan aged between 8 and 18 years. The study included public schools, private schools, UNRWAs schools, Zaatrai camp schools, and non-formal education centers. The Strengths and Difficulties Questionnaire was used to measure behavioral and emotional problems. Results: About 13.9% of the children had abnormal difficulty scores, and they suffered the most from emotional symptoms (17.9%). Syrian children in refugee camps had the highest rate of total difficulty (19.3%). In the adolescents, 19.7% had high levels of total difficulty, where conduct problems were the most reported (17.6%), and Syrian adolescents in refugee camps were highly affected (22.2%). The number of traumatic events, physical activity, problematic internet use, and family affluence were significantly associated with an increased risk of having behavioral and emotional problems in both the children and adolescents. Conclusions: A significant proportion of children and adolescents struggle with emotional and behavioral problems in Jordan, and serious efforts are needed to enhance the status of mental health for adolescents and children.
Characterization and Safety Assessment of a Novel Antioxidant Excipient from Sustainable Recovery of Grape Processing Waste Bentonite Designed to Develop a Thermosensitive Buccal Spray for Oral Cavity Wellness
Authors: Di Prima Giulia , Belfiore Elena , La Mantia Cecilia , Indelicato Serena , Avellone Giuseppe , De Caro Viviana
Published: December 2024

Background/Objectives: Nowadays, sustainability efforts focus on extracting natural cosmeceutical ingredients, such as polyphenols, from agri-food waste, for example, black bentonite (BB). The aims of this work were to validate an antioxidant cosmetic ingredient obtained from the waste BB and embed it into an ad hoc designed oromucosal spray intended for oral cavity wellness. Methods: Focusing on sustainability, the study tested PEG200, propylene glycol, and their mixtures as unconventional and green extraction solvents, aligned with a waste-to-market approach. The extracts obtained by maceration were characterized through HPLC-DAD and HPLC-MS analyses, DPPH, Bradford, and Folin–Ciocalteu assays. The best P extract was further subjected to OECD-compliant in vitro validation as novel cosmetic raw material and used to prepare a thermosensitive buccal spray for oral daily care. Results: PEG200 enabled the obtainment of a cost-effective polyphenol-rich extract, which was validated as a safe, high value-added cosmetic secondary raw material. The extract was incorporated into a liquid thermosensitive buccal formulation, able to gel once at body temperature and enhance polyphenol accumulation into the oral mucosae even with short contact times. Conclusions: BB is confirmed as a valuable source of polyphenols, and PEG200 represents an effective extraction solvent leading to a novel functional liquid excipient characterized by an OECD-compliant variegate pool of phenols. The buccal spray then proposed represents a valuable, friendly solution for daily oral care, as it is simple to use, as well as the in vitro and ex vivo tests carried out suggested its effectiveness.
Genetic Analyses of Flower, Fruit, and Stem Traits of Intergeneric Hybrids Between ‘Honghuagqinglong’ and ‘Heilong’ Pitayas
Authors: Pu Xinyue , Khan Imran , Zhang Tiantian , Huang Guohua , Chen Jiayi , Ding Yu , Ji Xuewu , Zhang Zhike , Zhao Jietang , Hu Guibing , Sabir Irfan Ali , Qin Yonghua
Published: December 2024

Pitaya is renowned for its delicious taste, high nutritional value, and economic as well as ornamental appeal. Breeding new pitaya varieties can boost economic returns by appealing to consumers with diverse morphological traits. However, the genetic basis underlying key traits in intergeneric hybrids of pitaya has yet to be fully understood. This study investigates the genetic dynamics in flower, fruit, and stem traits, including segregation patterns and a mixed inheritance model for major and polygenic traits, in an intergeneric hybridization between ‘Honghuagqinglong’ (HHQL) (Hylocereus stenopterus) and ‘Heilong’ (HL) (Selenicereus grandiflorus). The study identified normal or skewed, normal distribution patterns in seven floral, fifteen fruit, and five stem traits, indicating their quantitative nature governed by multiple genes. Specifically, flower size and color exhibited a hereditary bias towards ‘HL’ characteristics, while ‘HHQL’ significantly influenced the coloration of fruit peel and pulp. Fruit weight and total soluble solids (TSS) content decreased, whereas stem traits exhibited broader and thicker dimensions with fewer thorns. This study offers valuable insights into genetic variation and the influence of major genes on flower, fruit, and stem traits between ‘HHQL’ and ‘HL’ intergeneric hybrids, providing a useful reference for parental selection in pitaya breeding programs.
Modeling Floral Induction in the Narrow-Leafed Lupin Lupinus angustifolius Under Different Environmental Conditions
Authors: Duk Maria A. , Gursky Vitaly V. , Bankin Mikhail P. , Semenova Elena A. , Gurkina Maria V. , Golubkova Elena V. , Hirata Daisuke , Samsonova Maria G. , Surkova Svetlana Yu.
Published: December 2024

Flowering is initiated in response to environmental cues, with the photoperiod and ambient temperature being the main ones. The regulatory pathways underlying floral transition are well studied in Arabidopsis thaliana but remain largely unknown in legumes. Here, we first applied an in silico approach to infer the regulatory inputs of four FT-like genes of the narrow-leafed lupin Lupinus angustifolius. We studied the roles of FTc1, FTc2, FTa1, and FTa2 in the activation of meristem identity gene AGL8 in response to 8 h and 16 h photoperiods, vernalization, and the circadian rhythm. We developed a set of regression models of AGL8 regulation by the FT-like genes and fitted these models to the recently published gene expression data. The importance of the input from each FT-like gene or their combinations was estimated by comparing the performance of models with one or few FT-like genes turned off, thereby simulating loss-of-function mutations that were yet unavailable in L. angustifolius. Our results suggested that in the early flowering Ku line and intermediate Pal line, the FTc1 gene played a major role in floral transition; however, it acted through different mechanisms under short and long days. Turning off the regulatory input of FTc1 resulted in substantial changes in AGL8 expression associated with vernalization sensitivity and the circadian rhythm. In the wild ku line, we found that both FTc1 and FTa1 genes had an essential role under long days, which was associated with the vernalization response. These results could be applied both for setting up new experiments and for data analysis using the proposed modeling approach.
Multi Characteristic Analysis of Vascular Cambium Cells in Populus euphratica Reveals Its Anti-Aging Strategy
Authors: Han Xiaoli , Gai Zhongshuai , Sun Jianhao , Zhai Juntuan , Qiu Chen , Wu Zhihua , Li Zhijun
Published: December 2024

All multicellular organisms undergo senescence, but the continuous division of the vascular cambium in plants enables certain tree species to survive for hundreds or even thousands of years. Previous studies have focused on the development of the vascular cambium, but the mechanisms regulating age-related changes remain poorly understood. This study investigated age-related changes in the vascular cambium of P. euphratica trees aged 50 to 350 years. The number of cambium cells in the 50-year-old tree group was 10 ± 2, while the number of cambium cells in the 200-year-old and 350-year-old tree groups significantly decreased. The thickness of the cambium cells exhibited a similar trend. In addition, the net photosynthetic and transpiration rates continue to increase with age, but no notable differences were found in factors like average leaf area, palisade tissue thickness, and stomatal density. A total of 6491 differentially expressed genes (DEGs) were identified in the vascular cambium of P. euphratica at three distinct ages using RNA sequencing. The expression patterns of DEGs associated with cell division and differentiation, lignin biosynthesis, plant hormones, and transcription factors were analyzed. DEGs related to XTH, EXP, PAL, C4H, ABA, Br, GA, and others are highly expressed in older trees, whilst those encoding expansins, kinases, cyclins, 4CL, Auxin, Eth, SA, and others are more prevalent in younger trees. Gene family members, such as NAC, MYB, HD-ZIP III, WRKY, and GRF, have various regulatory functions in the vascular cambium. The findings offer insights into how ancient P. euphratica trees maintain vitality by balancing growth and aging, providing a foundation for future research on their longevity mechanisms.
Phenotypic and Genomic Analysis of Enterobacter ludwigii Strains: Insights into Mechanisms Enhancing Plant Growth Both Under Normal Conditions and in Response to Supplementation with Mineral Fertilizers and Exposure to Stress Factors
Authors: Sokolova Ekaterina Alexeevna , Mishukova Olga Viktorovna , Hlistun Inna Viktorovna , Tromenschleger Irina Nikolaevna , Chumanova Evgeniya Vladimirovna , Voronina Elena Nikolaevna
Published: December 2024

In this research study, we investigated four strains of Enterobacter ludwigii that showed promising properties for plant growth. These strains were tested for their ability to mobilize phosphorus and produce ammonium, siderophores, and phytohormones. The strains exhibited different values of PGP traits; however, the analysis of the complete genomes failed to reveal any significant differences in known genes associated with the expression of beneficial plant traits. One of the strains, GMG_278, demonstrated the best potential for promoting wheat growth in pot experiments. All morphological parameters of wheat were improved, both when GMG_278 was applied alone and when combined with mineral fertilizer. The combined effect we observed may suggest various mechanisms through which these treatments influence plants. The amount of pigments and proline suggests that bacterial introduction operates through pathways likely related to stress resilience. A study on the genetic mechanisms behind plant resilience to stress has revealed a significant upregulation of genes related to reactive oxygen species (ROS) defense after bacterial exposure. It is important to note that, in the initial experiments, the strain showed a significant production of salicylic acid, which is a potent inducer of oxidative stress. In addition, the synthesis of some phytohormones has been restructured, which may affect root growth and the architecture of root hairs. When combined with additional mineral fertilizers, these changes result in a significant increase in plant biomass.
Somatic Embryogenesis from the Leaf-Derived Calli of In Vitro Shoot-Regenerated Plantlets of Rosa hybrida ‘Carola’
Authors: Duan Mingao , Liu Juan , Zhao Yining , Wang Xiaofei , Li Longzhen , Wang Shiyi , Jia Ruidong , Zhao Xin , Kou Yaping , Su Kairui , Ge Hong , Yang Shuhua
Published: December 2024

Roses are one of the most important flowers applied to landscape, cut flowers, fragrance and food industries widely. As an effective method for plant reproduction, the regeneration via somatic embryos is the most promising method for breed improvement and genetic transformation of woody plants. However, lower somatic embryogenesis (SE) induction rates and genotypic constraints impede progress in genetic transformation in rose. This study describes a plant regeneration system for the famous red cut flower cultivar Rosa hybrida ‘Carola’. The stems without petioles cultured on Murashige and Skoog (MS) medium supplemented with 1.0 mg·L−1 6-benzylaminopurine (6-BA), 0.05 mg·L−1 a-naphthalene acetic acid (NAA) and 30 g·L−1 sucrose showed the maximum proliferation coefficient of shoots with 3.41 for the micropropagation system. We evaluated the effects of different plant growth regulators (PGRs) on the induction, proliferation and conversion of somatic embryos. The induction rate of calli reached 100% on MS medium supplemented with 2.0 g·L−1 NAA and 30 g·L−1 glucose. The highest induction rate of somatic embryos achieved a frequency of 13.33% on MS medium supplemented with 2.0 mg·L−1 zeatin (ZT), 0.1 mg·L−1 NAA and 30 g·L−1 glucose. The most suitable carbohydrate with 60 g·L−1 glucose resulted in a proliferation rate of somatic embryos (4.02) on MS medium containing 1.5 mg·L−1 ZT, 0.2 mg·L−1 NAA and 0.1 mg·L−1 gibberellic acid (GA3). The highest somatic embryos germination rate (43.33%) was obtained from the MS medium supplemented with 1.0 mg·L−1 6-BA, 0.01 mg·L−1 IBA and 30 g·L−1 glucose. Finally, the germinated somatic embryos successfully rooted on 1/2 MS medium containing 1.0 mg·L−1 NAA, 30 g·L−1 sucrose, and the vigorous plantlets were obtained after hardening-off culture. This study provided a stable and efficient protocol for plant regeneration via somatic embryos in R. hybrida ‘Carola’, which will be beneficial to the further theoretical study and genetic improvement in roses.
NIPAm Microgels Synthesised in Water: Tailored Control of Particles’ Size and Thermoresponsive Properties
Authors: Rath Gabriela , Mazzali Davide , Zarbakhsh Ali , Resmini Marina
Published: December 2024

Microgels, combining the properties of hydrogels and microparticles, are emerging as versatile materials for varied applications such as drug delivery and sensing, although the precise control of particle size remains a challenge. Advances in synthetic methodologies have provided new tools for tailoring of properties, however costs and scalability of the processes remains a limitation. We report here the water-based synthesis of a library of N-isopropylacrylamide-based microgels covalently crosslinked with varying contents of N,N′-methylenebisacrylamide. The results highlight the versatility of water as a synthetic medium, which yields large and monodisperse microgels, with excellent control over size. Dynamic light scattering data demonstrate that by increasing the total monomer concentration from 1 to 3 wt%, the particle size is increased by up to 4.9-fold. Crosslinker content allows fine-tuning of microgel size, with greater relevance for functionalised microgels. Functional co-monomers such as N-(3-aminopropyl)methacrylamide hydrochloride and N-(hydroxymethyl)acrylamide are shown to influence size and thermoresponsive behaviour, with hydrogen-bonding monomers reducing particle size and increasing the volume phase transition temperature by 2 °C. Positively charged monomers show a size reduction upon heating but provide colloidal stability at temperatures up to 60 °C. These findings emphasize the importance of tailoring synthetic conditions and formulations to optimize microgel properties for specific applications.
Diamine Crosslinked Addition-Type Diblock Poly(Norbornene)s-Based Anion Exchange Membranes with High Conductivity and Stability for Fuel Cell Applications
Authors: Li Quan , He Xiaohui , Feng Ling , Ye Jia , Zhang Wenjun , Huang Longming , Chen Defu
Published: December 2024

Anion exchange membranes (AEMs) as a kind of important functional material are widely used in fuel cells. However, synthetic AEMs generally suffer from low conductivity, poor alkaline stability, and poor dimensional stability. Constructing efficient ion transport channels is widely regarded as one of the most effective strategies for developing AEMs with high conductivity and low swelling ratio. Herein we demonstrate a versatile strategy to prepare the AEMs with both high conductivity and excellent alkali stability via all-carbon hydrogen block copolymer backbone hydrophilic crosslinking and introducing flexible alkoxy spacer chains. Additionally, we investigated the impact of the crosslinking degree on the AEMs’ performances. It was found that the dosage of the hydrophilic crosslinker has a significant impact on the construction of efficient ion transport channels in the AEMs. Amazingly, the CL30-aPNB-TMHDA-TMA exhibited the highest hydroxide conductivity (138.84 mS cm−1), reasonable water uptake (54.96%), and a low swelling ratio (14.07%) at 80 °C. Meanwhile, the membrane showed an excellent alkaline stability in a 1 M NaOH solution at 80 °C for 1008 h (ion exchange capacity (IEC) and OH− conductivity remained at 91.9% and 89.12%, respectively). The single cells assembled with CL30-aPNB-TMHDA-TMA exhibited a peak power density of 266.2 mW cm−2 under a current density of 608 mA cm−2 at 80 °C. The novel developed composite strategy of flexible alkoxy side chains with hydrophilic crosslinking modification is potentially promised to be an effective approach to develop the high-performance AEMs.
Preparation and Characterization of Highly Conductive PVDF/PAN Conjugate Electrospun Fibrous Membranes with Embedded Silver Nanoparticles
Authors: Wu Siyang , Zhang Luyu , Qiu Xiaochun , Guo Yuntai , Dong Liangliang , Guo Mingzhuo , Zhao Jiale
Published: December 2024

This study reports the development of highly conductive and stretchable fibrous membranes based on PVDF/PAN conjugate electrospinning with embedded silver nanoparticles (AgNPs) for wearable sensing applications. The fabrication process integrated conjugate electrospinning of PVDF/PAN, selective dissolution of polyvinylpyrrolidone (PVP) to create porous networks, and uniform AgNP incorporation via adsorption-reduction. Systematic optimization revealed that 10 wt.% PVP content and 1.2 mol/L AgNO3 concentration yielded membranes with superior electrical conductivity (874.93 S/m) and mechanical strength (2.34 MPa). The membranes demonstrated excellent strain sensing performance with a gauge factor of 12.64 within 0–30% strain and location-specific sensing capabilities: moderate movements at wrist (ΔR/R0: 98.90–287.25%), elbow (124.65–300.24%), and fingers (177.01–483.20%) generated stable signals, while knee articulation exhibited higher sensitivity (459.60–1316.48%) but significant signal fluctuations. These results demonstrate the potential of the developed conductive porous PVDF/PAN composite fibrous membranes for applications in wearable sensors, flexible electronics, and human-machine interfaces, particularly in scenarios requiring moderate-range motion detection with high reliability and stability. The findings suggest promising opportunities for developing next-generation wearable sensing devices through the optimization of conjugate electrospun fibrous membranes.
Electrospun Carbon Nanofibers Derived from Polyvinyl Alcohol Embedded with Bimetallic Nickle-Chromium Nanoparticles for Sodium Borohydride Dehydrogenation
Authors: Yousef Ayman , Maafa Ibrahim M. , Abutaleb Ahmed , Matar Saleh M. , Alamir Ahmed A. , El-Halwany M. M.
Published: December 2024

Bimetallic NiCr nanoparticles decorated on carbon nanofibers (NiCr@CNFs) were synthesized through electrospinning and investigated as catalysts for hydrogen generation from the dehydrogenation of sodium borohydride (SBH). Four distinct compositions were prepared, with chromium content in the catalysts ranging from 5 to 25 weight percentage (wt%). Comprehensive characterization confirmed the successful formation of bimetallic NiCr@CNFs. Notably, among the compositions, the catalyst containing 20 wt% Cr exhibited the highest efficiency in SBH dehydrogenation. Kinetic studies revealed that hydrogen production followed a first-order reaction with respect to the catalyst quantity. Additionally, the reaction time decreased with increasing temperature. The activation energy (Ea), entropy change (ΔS), and enthalpy change (ΔH) were calculated as 34.27 kJ mol−1, 93.28 J mol·K−1, and 31.71 kJ mol−1, respectively. The improved catalytic performance is attributed to the synergistic interaction between Ni and Cr. This study proposes a promising strategy for the advancement of Ni-based catalysts.
Damage and Failure Monitoring of Aerospace Insulation Layers Based on Embedded Fiber Bragg Grating Sensors
Authors: Yan Guang , Wan Boli , Huang Heng , Li Wuyi
Published: December 2024

Carbon fiber-reinforced polymer (CFRP) composites are widely used in aviation thermal insulation layers due to their high strength-to-weight ratio and excellent high-temperature performance. However, challenges remain regarding their structural integrity and durability under extreme conditions. This study first employed finite element simulation to model the damage evolution of CFRP laminated plates under axial tensile loads and their thermal decomposition behavior in high-temperature environments, providing a theoretical reference. Subsequently, experimental research was conducted on CFRP laminated plates embedded with fiber Bragg grating (FBG) sensors. In the tensile tests, FBG sensors accurately monitored the entire process from elastic deformation to damage propagation and eventual failure. In the high-temperature tests, despite a 75% reduction in tensile strength, FBG sensors effectively monitored damage evolution. Conclusively, the results demonstrate that FBG sensors possess reliable monitoring capabilities under complex conditions, making them a promising solution for the long-term structural health monitoring of aviation thermal insulation materials and paving the way for future developments in this area.
Synthesis and Study of Sorption Properties of Zinc-Imprinted Polymer
Authors: Zhakina Alma Khassenovna , Vassilets Yevgeniy Petrovich , Arnt Oxana Vasilievna , Zhakin Almat Maulenuly
Published: December 2024

Zinc-imprinted polymer (ZnIP) and non-imprinted polymer (NIP) were synthesized by radical polymerization, and their properties were studied. The novelty of the work lies in the use of humic acids isolated from coals of the Shubarkol deposit (Karaganda, Kazakhstan) as a basis for the imprinted polymer matrix, with methacrylic acid and ethylene glycol dimethacrylate as a functional monomer and a cross-linking agent, respectively. The composition and structure of ZnIP and NIP were characterized using various physicochemical methods. The specific surface area of ZnIP determined by the BET method was 40.60 ± 0.4 m2/g, which is almost twice as high as the similar indicator for NIP (21.50 ± 0.3 m2/g). In sorption tests of solutions with bimetallic ions, ZnIP demonstrates higher adsorption: 96.15% for Zn2+ and 74.88% for Pb2+, while NIP adsorbs only 81.33% and 60.11%, respectively. Sorption on both polymers is described by a pseudo-first-order equation (r > 0.99). The distribution coefficients for ZnIP are higher than for NIP. ZnIP has a relative selectivity that exceeds NIP by 2.90 times. The research results indicate the promise of using ZnIP for the selective removal of zinc ions from solutions of multicomponent systems, including wastewater, making it a valuable material for solving environmental and technological problems.
Effects of Phenoxazine Chromophore on Optical, Electrochemical and Electrochromic Behaviors of Carbazole–Thiophene Derivatives
Authors: Hu Bin , Song Haizeng , Zhang Xinlei , He Yuan , Ren Jingshun , Huang Jingbin
Published: December 2024

Phenoxazine, as an organic-small-molecule chromophore, has attracted much attention for its potential electrochromic applications recently. To develop appealing materials, phenoxazine chromophores were introduced at the N-position of carbazole–thiophene pigment, yielding two novel monomers (DTCP and DDCP), whose chemical structures were characterized by NMR, HRMS and FTIR. The results of the optical property study indicate that little influence could be observed in the presence of the phenoxazine chromophore. Corresponding polymer films on the surface of an ITO/glass electrode were obtained through electropolymerization. The electrochemical features displayed were various due to the introduction of the phenoxazine group. The spectroelectrochemical results demonstrate that the color of the polymer films could be changed. Compared with the PDDC films, the PDDCP films exhibited three different colors (tangerine, green and purple colors) in different redox states, which could be attributed to the synergistic effect between the carbazole–thiophene conjugate chain and the phenoxazine group. Moreover, fast switching time could be seen due to the presence of the phenoxazine chromophore. This study could provide a reference for obtaining high-performance electrochromic materials.
Polymeric Materials Used in 3DP in Dentistry—Biocompatibility Testing Challenges
Authors: Rus Florentina , Neculau Cristina , Imre Marina , Duica Florentina , Popa Alexandra , Moisa Radu Mihai , Voicu-Balasea Bianca , Radulescu Radu , Ripszky Alexandra , Ene Razvan , Pituru Silviu
Published: December 2024

In the latter part of the 20th century, remarkable developments in new dental materials and technologies were achieved. However, regarding the impact of dental resin-based materials 3D-printed on cellular responses, there have been a limited number of published studies recently. The biocompatibility of dental restorative materials is a controversial topic, especially when discussing modern manufacturing technologies. Three-dimensional printing generates the release of residual monomers due to incomplete polymerization of materials and involves the use of potentially toxic substances in post-printing processes that cannot be completely eliminated. Considering the issue of biocompatibility, this article aims to establish an overview of this aspect, summarizing the different types of biocompatibility tests performed on materials used in 3D printing in dentistry. In order to create this comprehensive review, articles dealing with the issue of 3D printing in dentistry were analysed by accessing the main specialized search engines using specific keywords. Relevant data referring to types of materials used in 3DP to manufacture various dental devices, polymerization methods, factors affecting monomer release, cytotoxicity of unreacted products or post-curing treatments, and methods for assessing biocompatibility were analysed. Although the introduction of new restorative materials used in dental treatments is subject to national and international regulations and standards, it is necessary to investigate them regarding biocompatibility in order to support or deny the manufacturers’ statements regarding this aspect.
The Variation Law of Fracture Conductivity of Shale Gas Reservoir Fracturing–Flowback Integration
Authors: Xu Dongjin , Li Zhiwen , Li Changheng , Guo Yukai
Published: December 2024

Hydraulic fracturing is a commonly used technical tool in the extraction process of unconventional shale gas reservoirs. However, the damage caused by fracturing fluids to the proppant fracture inflow conductivity during the whole fracturing, reentry, and production process is very obvious, which affects the fracturing and production increase effect. Conventional proppant fracture inflow conductivity test experiments only use a single-phase fluid in the gas or liquid phase to complete the test and evaluation, and few scholars have paid attention to the change rule of inflow conductivity during the whole fracturing and re-discharge process. Therefore, combined with the characteristics of shale gas production, we simulated the whole fracturing–returning–production process, carried out three consecutive phases of proppant fracture inflow conductivity test experiments, and investigated the change rule of fracture inflow conductivity during the whole process. The results show that under the condition of closure pressure 35 MPa, after distilled water simulated fracturing, the damage to mineral sand flow-conducting capacity is as high as 81.55% due to the effect of shale hydration. During the simulated return discharge process, the gas-measured flow-conducting capacity experiments were carried out at 25%, 50%, 75%, and 100% of the initial gas-measured discharge, and the fracture flow conductivity kept rising, and its maximum recovery value was 54.67% of the original one; the experiments simulated the fluctuations caused by changes in the wellbore flow pressure on the closure pressure in the process of production as well as the influence of fracture flow-conducting capacity under the condition of long-term soaking of the proppant, and the results of this study are useful for the design of fracturing programs and high-efficiency fracturing of shale gas. The results of this study have certain reference significance for the design and efficient development of shale gas reservoir fracturing programs.
Experimental Research on Influence of Calcium Channels on the Healing of Skin Wounds in Rats
Authors: Dobrițoiu-Grigore Alexandra , Stoleru Smaranda , Costescu Mihnea , Vătășescu Balcan Ana , Coman Oana Andreia , Zugravu Aurelian , Fulga Ion
Published: December 2024

The healing process involves cell migration, which is sustained by an electrical potential difference that emerges between the edges of skin wounds and the center of the wound. The electrical potential in cells’ membranes is responsible for their migration in an electric field. The differences in the transmembrane electrochemical gradient generate this potential. The concomitant blockade of potassium and calcium channels by amiodarone at a medium dosage favored wound healing, but the effect was less intense than in the case of the selective blocking of potassium channels. According to this suggestion, blocking calcium channels might have a partial effect on blocking potassium channels. Given that nimodipine inhibits both L-type and T-type calcium channels, we aimed to investigate which of these calcium channels are involved in wound healing. Hence, we performed an experimental study in which nimodipine was used in three concentrations: 200 nM, which blocks only L-type calcium channels, 1000 nM, which blocks both L-type and T-type calcium channels, and 10,000 nM, which blocks calcium channels and activates CB1 cannabinoid receptors, respectively. The present research is a continuation of previous studies conducted by us, aimed to propose new perspectives on wound treatment. In conclusion, the blocking of calcium channels favored wound healing under our experimental conditions, but this happened only by simultaneously blocking the L-type and T-type calcium channels, because only the medium nimodipine concentration had a statistically significant effect.
A Novel Martensitic Stainless Steel Material for CO2 Corrosion Environment
Authors: Sang Pengfei , Luo Wei , Li Wenzhe , Wang Chuanlei , Chen Ye , Zhou Lang , Ma Zihan , Wang Du , Duan Yunqi
Published: December 2024

The novel martensitic stainless steel 13CrU was developed based on 13CrS by adding trace alloying elements, such as Mo, Ni, and Ta. This study compares the mechanical and corrosion resistance properties of the two martensitic stainless steels to assess the effect of these alloying elements on 13CrU’s performance. Experimental results show that increasing Mo by 0.67 wt% and Ni by 1.13 wt% improves the yield strength of 13CrU by 11.6% compared to 13CrS. The addition of Ta enhances the corrosion resistance of 13CrU beyond that of 13CrS. Overall, the addition of trace alloying elements significantly improves the mechanical properties of 13CrU and enhances its resistance to CO₂ corrosion.
FDM 3D Printing Filaments with pH-Dependent Solubility: Preparation, Characterization and In Vitro Release Kinetics
Authors: Nascimento Gustavo M. , Cardoso Pedro H. N. , da Silva Eumara M. E. , Tavares Ginetton F. , Olivier Nelson C. , Faia Pedro M. , Araújo Evando S. , Silva Fabrício S.
Published: December 2024

The process of manufacturing drug delivery systems (DDSs) by fused deposition modeling (FDM) with 3D printing requires the availability of a polymeric filament containing the drug of interest. This filament is fused in the printer heating system and used to print polymer/drug volumetric parts. Polymers with pH-dependent solubility are widely known in the literature for their controlled release and drug dissolution-enhancing properties, biocompatibility, and variety of release profiles. Given these characteristics, the study of pH-responsive 3D printing filaments appears as a potential alternative for the development of new 3D printing functional materials for healthcare area applications. In this sense, this work aimed at the preparation and characterization of pH-dependent filaments of the Eudragit E 100 copolymer (E100) containing the model drug Amlodipine (Aml) for potential application in the manufacturing of DDSs by 3D printing. The E100/Aml filaments with two distinct drug concentrations were produced by hot-melt extrusion at 105 °C. The posterior chemical protonation treatment of the filaments for 60 min provided a significant improvement in their flexibility. Microstructural analysis (SEM, XRD, FTIR, and DLS) and thermal studies by DSC proved the feasibility of producing the filaments by hot-melt extrusion without the degradation of their constituent materials. The in vitro dissolution profiles of the E100/Aml samples were evaluated in simulated gastric and intestinal fluids. The facilitated solubility of the polymer in an acidic medium (pH = 1.2) was preserved in the filament form, with rapid and reproducible drug release from the polymer matrix. The saturation of the drug concentration in the medium occurred after 30 min of testing for E100/Aml models. A customized 3D part with geometry and fill control was also printed from E100/Aml filaments as proof of concept.
Enhancing Sustainable Energy Through Cutting-Edge Waste Biorefinery Technologies
Authors: Lee Yen-Yi , Srinivaas Masimukku , Li I-Cheng , Keharika Kapa , Pothu Ramyakrishna , Boddula Rajender , Al-Qahtani Noora , Huang Bo-Wun , Chang-Chien Guo-Ping
Published: December 2024

Biorefineries play a critical role in addressing current global sustainability challenges by converting renewable biomass into valuable products such as biofuels, biochemicals, and bioenergy. The necessity of biorefineries has increased due to the growing demand for eco-friendly alternatives to fossil fuels, mitigating climate change, and reducing environmental impact. Utilizing agricultural byproducts, forest residues, and municipal waste, biorefineries harness feedstock through techniques such as pretreatment, anaerobic digestion, and thermochemical transformation, alongside advanced methods including electrochemical processes, hydrogenation of bio-derived substances, and the implementation of complex biocatalysts within biomass-oriented biorefineries. These processes enhance the efficiency of bioenergy production by breaking down complex biomass into simpler components. The current capacity of biorefineries is expanding globally, with increasing interest in advanced technologies such as gasification, fermentation, and enzymatic conversion. While biorefineries offer significant potential for reducing waste and promoting a circular economy, challenges such as scalability and cost efficiency remain. Future trends include integrating new biotechnological advances and optimizing resource recovery systems to improve yield, profitability, and sustainability in the bioeconomy.
Yokoi Shōnan and Yangming Philosophy: A Clarification of Misunderstandings
Authors: Huang Ying
Published: December 2024

In modern Japanese academia, the view has been proposed that Yokoi Shōnan “gained insights from Wang Yangming’s teachings and promoted practical learning 有得于王学而兴实学”, suggesting that his ideas on practical learning were influenced by Yangmingism. However, proponents of this theory have not provided strong evidence to prove a connection between Yokoi Shōnan’s practical thought and Yangmingism. From Yokoi Shōnan’s writings, his attitude toward Yangmingism was largely critical. In fact, the formation of Yokoi Shōnan’s ideas on practical thought underwent a rather complex process, shaped by his experiences with domain school reforms, interactions with various Japanese intellectuals during his period of study abroad, his understanding of Western culture, and discussions in practical learning study groups. Therefore, attributing his inclination toward practical thought solely to the influence of a single ideology would be overly simplistic.
Combined Barrier–Target Coverage for Directional Sensor Network
Authors: Kósa Balázs , Bukovinszki Márk , Michaletzky Tamás V. , Tihanyi Viktor
Published: December 2024

Over the past twenty years, camera networks have become increasingly popular. In response to various demands imposed on these networks, several coverage models have been developed in the scientific literature, such as area, trap, barrier, and target coverage. In this paper, a new type of coverage task, the Maximum Target Coverage with k-Barrier Coverage (MTCBC-k) problem, is defined. Here, the goal is to cover as many moving targets as possible from time step to time step while continuously maintaining k-barrier coverage over the region of interest (ROI). This approach is different from independently solving the two tasks and then merging the results. An Integer Linear Programming (ILP) formulation for the MTCBC-k problem is presented. Additionally, two types of camera clustering methods have been developed. This approach allows for solving smaller ILPs within clusters, and combining their solutions. Furthermore, a polynomial-time greedy algorithm has been introduced as an alternative to solve the MTCBC-k problem. An example was also provided of how the aforementioned methods can be modified to handle a more realistic scenario, where only the targets detected by the cameras are known, rather than all the targets within the ROI. The simulations were run with both dense and sparse camera placements, convincingly supporting the usefulness of the clustering and greedy methods.
Research on Parameter Compensation Method and Control Strategy of Mobile Robot Dynamics Model Based on Digital Twin
Authors: Li Renjun , Shang Xiaoyu , Wang Yang , Liu Chunbai , Song Linsen , Zhang Yiwen , Gu Lidong , Zhang Xinming
Published: December 2024

Inspection robots, which improve hazard identification and enhance safety management, play a vital role in the examination of high-risk environments in many fields, such as power distribution, petrochemical, and new energy battery factories. Currently, the position precision of the robots is a major barrier to their broad application. Exact kinematic model and control system of the robots is required to improve their location accuracy during movement on the unstructured surfaces. By a virtual engine and digital twins, this study put forward a visualization monitoring and control system framework which can address the difficulties in the intelligent factories while managing a variety of data sources, such as virtual–real integration, real-time feedback, and other issues. To develop a more realistic dynamic model for the robots, we presented a neural-network-based compensation technique for the nonlinear dynamic model parameters of outdoor mobile robots. A physical prototype was applied in the experiments, and the results showed that the system is capable of controlling and monitoring outdoor mobile robots online with good visualization effects and high real-time performance. By boosting the positional accuracy of robots by 18% when navigating obstacles, the proposed precise kinematic model can increase the inspection efficiency of robots. The visualization monitoring and control system enables visual, digital, multi-method, and complete real-time inspections in high-risk factories, such as new energy battery factories, to ensure the safe and stable operations.