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Polyethylene terephthalate(PET) is difficult to be irradiation cross-linked at low dose for the aromatic groups. In this paper, trimethylolpropane triacrylate (TMPTA) was incorporated in PET fibers to sensitize the cross-linking. Changes in PET fibers subjected to electron beam irradiation at dose up to 200 kGy and dose rate 12 kGy/s were investigated by gel content, scanning electron microscopy, differential scanning calorimetry, X-ray diffraction, thermal gravimetric analysis and X-ray photoelectron spectroscopy. The gel content was 0.14% at dose of 60 kGy and it arrived at the maximum value 0.53% at 100 kGy. Irradiated fibers showed a decrease in the breaking strength and an increase in the elongation at break. The crystal form of PET fibers had not been changed and crystallinity decreased 28% with the increasing dose. The melting temperature shifted from the original 254.28 °C to 253.44 °C. The thermal stability and the amount of non-volatile residue at 800 °C increased at dose of 100 kGy. XPS analysis indicated that the number of C-C band increased to prove the occurring of cross-link. The surface of PET fibers got rougher after irradiation and the anti-dripping property had not been improved effectively for the low degree of cross-linking. [ABSTRACT FROM AUTHOR]

Polytetrafluoroethylene (PTFE) possesses remarkable heat stability, combustibility and low coefficient of friction. In this paper, a kind of new PTFE yarn was spun from PTFE membrane via the method of scrolled-membrane spinning. The morphology of the resultant yarns was characterized by scanning electron microscope. Furthermore, the properties of the yarns were investigated as follow: Single-Yarn Electronic Tensile Strength Tester was used to test the mechanical property, and the dynamic coefficient of friction tester was used to calculate the friction coefficient. And the thermodynamic property of the PTFE yarns was shown by DSC, which the remarkable heat stability demonstrated, containing thermal shrinkage property. Furthermore, the combustibility was investigated and the result showed that the PTFE fiber and Nomex/PTFE fabric possessed desirable thermal properties, where the former was better than the latter. [ABSTRACT FROM AUTHOR]

To enhance the mechanical performance and ultraviolet shielding property, graphene oxide was incorporated as the functional nanofiller into a sodium alginate matrix to form a composite film via a solvent-casting method. The as-obtained films were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermal gravimetric; their mechanical and ultraviolet blocking properties were also systemically evaluated and compared. The results showed that the maximum tensile strength increased to 84 MPa at 6 wt.% graphene oxide loading, nearly 265% greater than that of pure sodium alginate film. The increased tensile strength may have resulted from the existence of hydrogen bonding and high interfacial adhesion between graphene oxide filler and sodium alginate matrix. Furthermore, the sodium alginate/graphene oxide films also demonstrated robust ultraviolet shielding capacity; the corresponding ultraviolet protection factor reached up to 133.61 at 8 wt.% graphene oxide loading. [ABSTRACT FROM AUTHOR]

In this article, submicron barium sulfate particles, as the radiation-resistant component, were incorporated into regenerated cellulose spinning solution. Then a series of X-ray radiation-resistant fibers were fabricated via a primarily industrialized wet-spinning trail, and the resultant fibers were knitted into fabrics by knitting loom. The morphology and structure of the fibers were studied with the aid of scanning electron micrography, Fourier-transform infrared spectroscopy, and X-ray diffraction. The composite fibers exhibited reasonably good properties, which met the criteria of mechanical requirements of commercial textiles—dry breaking strength and elongation (>1.5 cN/dtex and 26%) and wet breaking strength and elongation (>1.4 cN/dtex and 22%) and permanent laundry-resistant abilities even after being washed 20 times. An effective and feasible X-ray radiation-resistant method, the medical digital X-ray photography system, was proposed to evaluate the radiation resistance of the composite fiber and its fabric. The X-ray attenuation ratio of the sample tended to increase with increasing barium sulfate content and finally reached a dose of a 0.1 mmPb lead equivalent. Therefore, these fibers and fabrics can be utilized as the base materials for X-ray radiation-resistant lightweight apparel and detective surgical yarn. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile (PAN) composite microfibers with different contents of graphene oxide (GO) were fabricated via wet‐spinning route in this work. Based on nonsolvent‐induced phase separation theory, N,N‐dimethyl formamide/water mixture system was employed as coagulation bath, nonsolvent (water) diffused into PAN spinning solution and led to a quick PAN fiber solidification. Nematic liquid crystal state of GO dispersions and GO/PAN spinning solutions were determined via polarized optical microscopy images, and the morphology and structure of the composite fibers were characterized via scanning electron microscope, Transmission electron microscopy, Fourier transform infrared spectra, and X‐ray diffraction. 1 wt % GO/PAN composite fibers exhibited outstanding mechanical properties, 40% enhancement in tensile strength and 34% enhancement in Young's modulus compared with pure PAN fiber. The results of dynamic mechanical analysis indicated that the composite fiber with 1 wt % GO performed the best thermal mechanical property with 5.5 GPa and 0.139 in storage modulus and loss tangent, respectively. In addition, thermogravimetric analysis showed that thermal stability of the composite fibers enhanced with the increasing GO contents. GO/PAN composite fibers can be as the candidate of carbon fiber precursor, high performance fibers, and textiles applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46950. [ABSTRACT FROM AUTHOR]

[Display omitted] • A system configuration determination metric is proposed to balance FOV H and precision. • A background segmentation model based on the fusion of CNN-Transformer is proposed to enhance the system's stability. • A novel method of rectifying the displacement error induced by the camera orientation is proposed. • The efficacy of the robust monocular vision-based monitoring system (RMVMS) is validated through a tied arch bridge. Vision-based multi-target monitoring systems for bridge structures provide a comprehensive evaluation of structural safety. However, their application to field bridges has been constrained by challenges such as the trade-off between the field of view (FOV) and accuracy, as well as the impact of camera orientation and complex backgrounds on measurement effectiveness. This study introduces a robust monocular vision-based monitoring system (RMVMS) for multi-target displacement measurement. First, a system configuration determination method is developed to achieve an effective balance between FOV and accuracy. Next, a hybrid network structure, ConvTransNet, is introduced to mitigate the impact of complex background disturbance. Additionally, a novel multi-target displacement transformation model (MDTM) is proposed to correct errors arising from camera orientation. Moreover, a boundary loss function and an RMSProp learning rate schedule were implemented during training, enabling ConvTransNet to achieve optimal performance with a P-R threshold of 0.45. A 4-meter laboratory-scale bridge model test demonstrated the superiority of ConvTransNet over existing segmentation models on a custom dataset formatted according to Pascal VOC 2012 standards. MDTM effectively reduced orientation-induced errors from 17.93 % to 1.53 %. The efficiency and robustness of RMVMS were further validated on a tied arch bridge, achieving RMSE and NRMSE below 0.162 mm and 3.63 %, respectively, confirming its capability for precise multi-target displacement monitoring in field applications. [ABSTRACT FROM AUTHOR]

To give full play to the good performance of polyphenylene sulfide (PPS) fiber, electron beam irradiation was used to promote the property of the PPS fiber. The fibers were irradiated at different doses, and changes in structure and property of PPS fibers were analyzed by X-ray diffraction, moisture regain, heat resistance and thermo-gravimetric analysis. The strength of the specimen increased from 3.75 cN dtex−1 to 3.88 cN dtex−1 at 10 kGy and then decreased. And the elongation of the irradiated fibers decreased after irradiation. The crystalline shape of the fibers did not change and the crystallinity increased from 57.3% to 59.4% and then decreased. Irradiation had the good effect on moisture regain and heat resistance. The moisture regain of PPS fibers increased from 0.28% to 0.74% after 60 kGy irradiation which was 2.6 times of the initial fibers. After heating at 150 °C for 2 h in an oven, the mass loss ratio of the fibers decreased from the original 9.96%–4.97% at 10 kGy dose which was helpful to the application of PPS fiber in high-temperature fields. At the same time, it could be seen from TG data that the maximum loss rate temperature of fibers rose from the initial 526.6 °C–532.7 °C. • Study on the modification of PPS fiber by low energy electron beam irradiation technique. • The strength and crystallinity of the fibers were changed under different doses of irradiation. • After irradiation, the hygroscopicity, heat resistance and thermal stability of the fiber were enhanced. [ABSTRACT FROM AUTHOR]

Bicomponent functional fibers with tunable structures are deemed as the promising building blocks for flexible asymmetric wearable devices and actuators. However, tunable structures of bicomponent fiber cannot be facilely achieved via conventional spinning routes. Herein, we developed a new strategy for structure-tunable fabrication of graphene oxide/alginate bicomponent fibers with different cross-section shapes via the microfluidic spinning route. Four distinct radial cross-section formations of bicomponent fibers: skin-core, eccentric structure, sandwich shapes and reverse core construction, are easily and instantaneously achieved through adjusting some basic parameters of the microfluidic spinning route. Computational fluid dynamics method is also utilized to simulate the flow behavior in the microfluidic channels during the microfiber shaping process. The structural fibers possessed unique properties corresponding to its structure configurations, i.e., skin-core shaped fibers exhibited the good tensile strength (235 MPa), while fibers with reverse core construction show admirable electrical conductivity (2000 S m−1) and outstanding electrochemical performance. This microfluidic spinning strategy offers a facile and environmental-friendly route to fabricate structure-tunable fibers without replacing the spinning templates, and provide a novel path to achieve flexible asymmetric wearable devices and actuators. Image 1 [ABSTRACT FROM AUTHOR]

Abstract Smart textile has been an attractive and promising issue in the field of artificial intelligent system. As the critical component of smart textile, the energy storage textiles are tending toward the directions of lightweight, portable, wearable and flexible. Developing flexible and wearable supercapacitors (SCs) has become a promising strategy to achieve seamless integration to garment. Herein, the planar flexible all-solid SC model was proposed in our work based on the graphene-and-MnO 2 -deposited fibrous nonwoven fabric. Graphene nanosheets and MnO 2 were deposited on the prepared cellulose nonwoven fabric via capillarity-assisted assembly coating method and in-situ chemical growth method respectively. The assembled graphene/MnO 2 SC exhibits good electric conductivity, excellent flexibility, a high specific capacitance of 138.8 mF/cm2, outstanding cycle life and bending properties of remaining 87.6% of the initial capacitance under 180° bending angles for 1000 cycles. The effect of the substrate texture structure (nonwoven and woven structure) was also investigated. To demonstrate the application of our all-solid SC, three devices connected in series could easily light six LED with a logo of "smiling". The assembled GMNF-SC can be acted the reasonable energy storage candidates for the wearable devices with the seamless integration to garment. Highlights • The hydrophilic cellulose nonwoven fabric is selected as the flexible substrate. • The capillarity-assisted assembly is applied to deposit graphene nanosheets. • The in-situ growth method is applied to deposit MnO 2 nanoparticles. • The all-solid SC exhibits good performance due to the big specific area. [ABSTRACT FROM AUTHOR]

• We derived an analytical solution to the impact of seasonal vegetation changes on ET. • Global ET elastic response to seasonal LAI changes has a north-south shift trajectory. • The weak negative ET elastic response to vegetation changes was found under low LAI. Seasonal variation of vegetation profoundly affects the water cycle. However, the seasonal divergence of evapotranspiration (ET) sensitivity in response to vegetation variations has not been fully understood. Here we derived an analytical solution to examine the impact of seasonal vegetation changes on ET with an extended Budyko framework based on an improved ET algorithm with improved water balance constraints. Results reveal a clear seasonal divergence of ET sensitivity to vegetation coverage changes across climate regimes and biomes. Generally, the high ET sensitivity to vegetation coverage has a clear north-south shift trajectory from spring to winter. For moderate-humid regions (0.7 < aridity index < 1.0), vegetation exhibits higher importance in altering ET in March-September. While for moderate-dry regions (1.0 < aridity index < 1.4), the sensitivity of ET to vegetation changes is the highest in September-November. Moreover, the spatial-temporal pattern of ET sensitivity to seasonal vegetation changes is different between short vegetation cover and forest. Additionally, negative ET sensitivity to vegetation coverage changes was discovered in regions with seasonal precipitation of less than 500 mm and sparse vegetation coverage (predominant land cover types of grassland, scrubland, and savannas). In summary, our study provides an analytical solution to estimate ET sensitivity to seasonal vegetation changes within the extended Budyko framework. The results highlight the difference in hydrological response to vegetation dynamics across seasons and vegetation types. [ABSTRACT FROM AUTHOR]

• The actuator has excellent flexibility and controllability. • Actuators have large bending angle at low driving voltage. • "U"-shaped can achieve large deformation under low constraints. • Flexible smart gripper can effectively grasp objects as the hand of robot. • Grasping direction of flexible smart gripper is longitudinal and transverse. Self-driven smart materials have a wide range of applications in smart textiles, artificial muscles, soft robots, human-machine interactions and so on. Flexible electrothermally driven smart materials are essentially required in self-driven smart devices due to their excellent flexibility and simple operation. However, there are still some issues should be solved such as the high driving voltage, how to achieve excellent driving performance at low voltage is highly desired. In this work, three kinds of flexible double-layer electrothermal actuators (ETAs) are made of "U"-shaped graphite paper and polyimide (PI) film. The thermal expansion coefficients of graphite and PI vary widely and graphite has excellent electrothermal performance, which enable flexible double-layer ETA has a good driving performance at low voltage in a short time. The bending angle of the actuator can reach 248.6° and the bending curvature can reach 1.23 cm −1 at 6 V such low driving voltage in ten seconds, meanwhile, exhibits excellent driving performance and high durability. Two ETAs were assembled into a flexible smart gripper and the gripper can achieve the desired driving performance while applying a low voltage. By combining the actuator with the robot design the smart robot that can execute commands for grasping objects smoothly while moving freely. It has great potential in various human-machine interactions fields and intelligent drive fields. [ABSTRACT FROM AUTHOR]

• Dowel size significantly affects the load capacity of dowel-brick structure. • Load capacity of structure is related to the loading direction. • Stiffness of the structure is greatly influenced by dowel size and loading direction. To ensure the structural integrity of graphite reflector and the insertion of the control rod in the seismic event, a finite element analysis (FEA) of the whole graphite core in Thorium-based Molten Salt Reactor (TMSR) is urgently required. The stiffness of the dowel-brick structure is one of the most crucial parameters to verify the finite element model in whole core modelling. In this paper, ten non-failure and ten failure tests have been carried out to study the stiffness and load capacity of the dowel-brick structure and to investigate how the size of the dowel affects these parameters. In addition, two groups of FEA have been performed first, whose results are used to design the above tests. The numerical and experimental results indicate that the load capacity of dowel-brick structure is significantly affected by the height of the dowel and the direction load applied. The failure load in the direction perpendicular to the line connecting two dowels is obviously higher than that in the parallel direction. Meanwhile, due to most of cracks occurring in the lower brick, it is identified as the weakest one in the dowel-brick structure. Furthermore, when the dowel is short, the equivalent stiffness coefficients of the dowel-brick structure in directions parallel and perpendicular to the line connecting two dowels are approximately equal. However, the latter will be much higher than the former when the dowel is long enough. The stiffness coefficients of the structure in two directions increase slightly as the diameter of the dowel increasing. The experimental results have been used in the numerical analysis of the whole graphite core modeling in TMSR. [ABSTRACT FROM AUTHOR]

Lead halide perovskite has demonstrated remarkable potential in the wearable field due to its exceptional photoelectric conversion capability. However, its lead toxicity issue has consistently been subject to criticism, significantly impeding its practical application. To address this challenge, an innovative approach called lead-rivet was proposed for the in-situ growth of perovskite crystalline structures. Through the formation of S-Pb bonds, each Pb 2+ ion was firmly immobilized on the surface of the silica matrix, enabling in situ growth of perovskite nanocrystals via ion coordination between Cs + and halide species. The robust S-Pb bonding effectively restricted the mobility of lead ions and stabilized the perovskite structure without relying on surface ligands, thereby not only preventing toxicity leakage but also providing a favorable interface for depositing protective shells. The obtained perovskites exhibit intense and narrow-band fluorescence with full-width at half-maximum less than 23 nm and show excellent stability to high temperature (above 202 °C) and high humidity (water immersion over 27 days), thus making it possible to be used in varies textile technologies including melt spinning and wet spinning. The lead leakage rate of particles is only 4.15 % demonstrating excellent toxicity inhibition performance. The prepared fibers maintained good extensibility and flexibility which could be used for 3D-printing and textiles weaving. Most importantly, the detected Pb 2+ leaching was negligible as low as to 0.732 ppb which meet the standard of World Health Organization (WHO) for drinking water (<10 ppb), and the cell survival rate remained 99.196 % for PLA fluorescent filament after 24 h cultivation which showing excellent safety to human body and environment. This study establishes a controllable and highly adaptable synthesis method, thereby providing a promising avenue for the safe utilization of perovskite materials., Competing Interests: Declaration of Competing Interest We wish to draw the attention of the Editor to following facts may be considered as potential conflicts of interest and to significant financial contributions to this work. We confirm that the manuscript has been read and approved by all named authors and that there are no other persons who satisfied the criteria for authorship but are not listed. We further confirm that the order of authors listed in the manuscript has been approved by all of us. We confirm that we have given due consideration to the protection of intellectual property associated with this work and that here are no impediments to publication, including the timing of publication, with respect to intellectual property. I so doing we confirm that we have followed the regulations of our institutions concerning intellectual property. We understand that the corresponding Author is the sole contact for the Editorial process (including Editorial Manager and direct communications with the office). He is responsible for communicating with the other authors about progress, submissions of revisions and final approval of proofs. We confirm that we have provided a current, correct email address which is accessible by the Corresponding Author and which has been configured to accept email from chaoyuyou@qdu.edu.cn., (Copyright © 2024 Elsevier B.V. All rights reserved.)

We extend the highly-parallelizable open-source electronic transport code TRANSEC (Feldman et al 2014 Phys. Rev. B 90 035445;https://gitlab.com/computational-physics2/transec/) to perform real-space atomic-scale electronic transport calculations with periodic boundary conditions in the lateral dimensions. We demonstrate the use of TRANSEC in periodic Cu and Rh bulk structures and in large periodic Rh point contacts, in preparation to perform calculations of reflection probability across Rh grain boundaries., (© 2024 IOP Publishing Ltd.)

An ethyl 3-aminobenzo[b]thiophene-2-carboxylate derived ratiometric Schiff base fluorescent sensor R was devised and synthesized. R exhibited a highly sensitive and selective ratiometric response to In 3+ in DMF/H 2 O tris buffer solution. R exhibited a colorimetric/fluorescent dual-channel response to In 3+ . More importantly, R can distinguish In 3+ from Ga 3+ and Al 3+ in less than 5 min. R exhibited a good linear correlation with the concentration of In 3+ in the 5-25 μM range and the limit of detection for In 3+ was found to be 8.36 × 10 -9  M. According to the job`s plot and MS spectra, R formed a complex with In 3+ at 1:2 with a complexation constant of 8.24 × 10 9 M 2 . Based on Gaussian theory calculations, the response mechanism of R to In 3+ can be explained by photo-induced electron transfer (PET) and intramolecular charge transfer (ICT) mechanisms. In addition, R can be used for the detection of indium in tap water with satisfactory recoveries. Meanwhile, R displayed a linear relationship to micromolar concentrations (0-50 μM) of Pb 2+ and recognized Pb 2+ in a ratiometric response with a detection limit of 8.3 × 10 -9  M., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Chronic alcohol consumption, which is observed worldwide, can damage pancreatic tissue and promote pancreatitis. Rhubarb is a widely used traditional Chinese herbal medicine for treating pancreatitis in China. However, few pharmacological studies have investigated its epigenetic regulation. In this study, we investigated whether chronic exposure to alcohol can alter inflammatory gene expression and the epigenetic regulation effect of cooked rhubarb in the pancreatic tissue of rats. First, changes in inflammatory cytokine DNA methylation (IL-10, IL-1α, TNF-α, NF-κB and TGF-β) were detected in pancreatic tissue of Sprague-Dawley rats with varying alcohol exposure times (4, 6, 8, or 12 weeks), and then with varying doses of cooked rhubarb treatment (3, 6, or 12 g/day). DNA methylation levels, related RNA concentrations and protein expression of specific inflammatory cytokines, and histopathological score were analysed in pancreatic tissue of Sprague-Dawley rats. The results showed that chronic alcohol exposure (8 weeks) reduced the level of IL-1α DNA methylation and increased its protein expression in acinar cells (P < 0.05). In the acinar cells, the level of IL-10 DNA methylation increased, resulting in a reduction of protein expression (P < 0.05). Simultaneously, chronic alcohol exposure increased the pathological damage to the pancreas (P < 0.05). Finally, cooked rhubarb treatment (3 g/kg/day) effectively alleviated these changes in pancreatic tissue from chronic alcohol exposure (P < 0.05). These results indicate that chronic exposure to alcohol leads to changes in DNA methylation and protein expression of inflammatory genes, and cooked rhubarb may have a protective effect on the pancreatic tissue of rats., (Copyright © 2022. Published by Elsevier Masson SAS.)

Water pollution is one of the most pervasive problems afflicting people. Therefore, seeking highly efficient, low-cost methods to decontaminate water is very much in demand. In this paper, chitosan/polyvinyl-alcohol composite sponges are synthesized via foamed cross-linking method while incorporating different amount of graphene oxide, the resultant graphene oxide/chitosan/polyvinyl-alcohol composite sponges (GCS) are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR), indicating the reasonable dispersion of graphene oxide in the matrix. Furthermore, some physical properties (water absorption, water retention, apparent density, porosity) are also determined; water absorption is high up to 873%, apparent density is lower than 0.25 g/cm3, and porosity could reach 78%. The GCSs also manifest high adsorption ability, as effective adsorbent for Acid Red 37 (AR 37) solution. The relationship between adsorption capacity and independent variables (adsorbent mass, initial dye concentration, and contacting time) is obtained. The optimal adsorption capacity value of AR 37 on GCS could reach 421.5 mg/g.