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1.
3D Print Addit Manuf ; 11(3): e1287-e1297, 2024 Jun.
Article in English | MEDLINE | ID: mdl-39359580

ABSTRACT

Cork-based formulations adapted to binder jetting processes were herein developed and investigated. Two cork powder sets with different particle size distributions were studied to evaluate cork particles' ability to pack. Cork powders exhibiting a coarse distribution revealed a higher packing ability. In addition, owing to cork's lower affinity to water-based binders, the addition of two hydrophilic additives was explored. 3D-printed (3DP) cork parts with a simple geometry were first printed. An innovative technique was evaluated as a postprocessing phase to improve cork particle adhesion after printing. Inspired by the production of expanded cork agglomerates, use of autoclave technique as a postprocessing phase for cork parts was proposed. After the autoclave, 3DP parts exhibited an improved adhesion of cork particles, demonstrated by morphological and mechanical analyses. Fourier transform infra-red analyses demonstrated that the polysaccharide and suberinic fractions were also affected by the autoclave. 3DP cork parts with a complex design solution were successfully printed. This study contributes to new and complex design solutions for cork-based products maintaining cork's natural lightness, warmness, and softness to the touch.

2.
3D Print Addit Manuf ; 11(3): e1213-e1226, 2024 Jun.
Article in English | MEDLINE | ID: mdl-39359588

ABSTRACT

Boron-based aids are commonly introduced to tackle the unsatisfactory densification of SS316L parts fabricated by binder jetting (BJ) technology. However, there is scarce study on the effect of sintering aids on the mechanical performance. This work investigates the effect of B4C aids and sintering temperature on the mechanical performance and microscopic morphology of BJ printing SS316L parts. SS316L powders with a bimodal size distribution were adopted to enhance density and reduce the shape distortion. Besides, B4C was added as a sintering aid to promote densification during sintering. The results show that the bimodal powder is in favour of the density increase and the sintering process. The sintering temperature is largely reduced with the addition of B4C. Further, the mechanical performance is mainly affected by the final density and B4C content. In view of a comprehensive evaluation of shape retention and properties, B4C content of 1 wt.% and sintering temperature of 1250°C are expected to be the optimal parameters.

3.
3D Print Addit Manuf ; 11(4): e1606-e1615, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39360131

ABSTRACT

The application of binder jet 3D printing technology in the pharmaceutical field is developing rapidly. The properties of the ink are very important, affecting the stability of the ejection and the precision of the finished product, but there is a great lack of research on pharmaceutical inks. This study used solvents and excipients commonly used in pharmaceuticals to quantify the printability of inks using printability Z value theory, while using an ink-jet printing and observation platform to analyze the droplet ejection state of different composition inks from microscopic level. Studies have shown that compared to ethanol, the ejection effect of droplets was better when isopropanol was added to the ink, and the proportion added should not be greater than 40%; as the molecular weight of polyvinylpyrrolidone (PVP) increased, the concentration of PVP tolerated by the ink decreased; glycerin has a high ejection efficiency when the proportion is within 10%. In summary, a superior ink formulation of 40% aqueous isopropanol plus 0.1% PVP K30 and 4% glycerin was obtained. With this ink, levetiracetam dispersible tablets were prepared with a smooth printing process and the tablets had good appearance, good mechanical properties, and rapid release. This study provides a mutual validation of the Z value theory and the results of droplet ejection and tablet printing, while providing good ideas.

4.
Article in English | MEDLINE | ID: mdl-39361831

ABSTRACT

Silicon oxide-based (SiOx-based) materials show great promise as anodes for high-energy lithium-ion batteries due to their high specific capacity. However, their practical application is hindered by the inevitable volumetric expansion during the lithiation/delithiation process. Constructing high-performance binders for SiOx-based anodes has been regarded as an efficient strategy to mitigate their volume expansion and preserve structural integrity. In this work, we propose a green water-solution PAA-LS binder composed of poly(acrylic acid) (PAA) and sodium lignosulfonate (LS) with fast self-healing properties. The designed binder can be restored due to the strong affinity between Fe3+-catechol coordination bonds, thereby effectively alleviating the volumetric strain of SiOx-based anodes. Notably, with an optimized LS content of 0.5%, the SiOx@PAA-LS electrode exhibits excellent performance, delivering a high capacity of 997.3 mAh g-1 after 450 cycles at 0.5 A g-1. Furthermore, the SiOx||NCM622 full cell also demonstrates superior cycling stability, maintaining a discharge capacity of 147.58 mAh g-1 after 100 cycles at 0.5 A g-1, with an impressive capacity retention rate of 82.72%.

5.
Small ; : e2405823, 2024 Sep 29.
Article in English | MEDLINE | ID: mdl-39344160

ABSTRACT

The practical application of Li-S batteries, which hold great potential as energy storage devices, is impeded by various challenges, such as capacity degradation caused volume change, polysulfide shuttling, poor electrode kinetics, and safety concerns. Binder plays a crucial role in suppressing volume change of cathode side, thereby enhancing the electrochemical performance of Li-S batteries. In this research, a novel network binder (SA-Co-PEDOT) composed of sodium alginate is presented, Co2+ ions as cross-linking agent and PEDOT as an electronic conductor. The theoretical analysis and experimental testing confirm that the SA-Co-PEDOT binder with synergistic combination of catalytic center and electron transfer network effectively mitigates large volumetric changes during cycling while simultaneously enhancing electrode kinetics through controlling the deposition morphology of sulfur end product and its nucleation and dissolution. As a result, it achieves a capacity of 844 mAh g-1 after 150 cycles at 0.2 C. Moreover, the electrode with SA-Co-PEDOT binder subjected a bending test maintains a capacity of 395 mAh g-1 after 500 cycles at 0.5 C, exhibiting an impressively low decay rate of only 0.11%. Even with an ultra-low content of 2 wt.% SA-Co-PEDOT binder, the electrode still maintains a capacity of 999.7 mAh g-1 after 100 cycles at 0.5 C.

6.
Biomedicines ; 12(9)2024 Sep 23.
Article in English | MEDLINE | ID: mdl-39335674

ABSTRACT

Bone grafts are commonly used in orthopedic and dental surgeries to facilitate bone repair and regeneration. A new type of bone graft, polycaprolactone-infiltrated three dimensionally printed hydroxyapatite (3DP HA/PCL), was previously developed by infiltrating polycaprolactone (PCL) into preformed three-dimensional-printed hydroxyapatite (3DP HA) that was fabricated using binder jetting technology combined with a low-temperature phase transformation process. However, when producing small granules, which are often used for bone grafting, issues of granule agglomeration emerged, complicating the application of this method. This study aimed to develop a fabrication process for 3DP HA/PCL bone graft granules using solution infiltration and liquid agitation. The effects of varying PCL solution concentrations (40% and 50% w/w) and different agitating liquids (deionized water or DI, N-Methyl-2-Pyrrolidone or NMP, and an NMP-DI mixture) on the properties of the resulting composites were investigated. XRD and FTIR analysis confirmed the coexistence of HA and PCL within the composites. The final PCL content was comparable across all conditions. The contact angles of 3DP HA/PCL were 26.3 and 69.8 degree for 40% and 50% PCL solution, respectively, when using DI, but were zero when using NMP and NMP-DI. The highest compression load resistance and diametral tensile strength were achieved using the 50% PCL solution with DI or the NMP-DI mixture. DI resulted in a dense PCL coating, while NMP and the NMP-DI mixture produced a porous and irregular surface morphology. All samples exhibited a porous internal microstructure due to PCL infiltration into the initial pores of the 3D-printed HA. Biocompatibility tests showed that all samples supported the proliferation of MC3T3-E1 cells, with the greatest OD values observed for the 50% PCL solution with DI or the NMP-DI mixture at each cultured period. Considering the microstructural, mechanical, and biological properties, the 50% PCL solution with the NMP-DI mixture demonstrated overall desirable properties.

7.
JACC Heart Fail ; 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39340493

ABSTRACT

BACKGROUND: For heart failure with reduced ejection fraction (HFrEF), suboptimal use of renin-angiotensin-aldosterone system inhibitors (RAASis), including mineralocorticoid receptor antagonists (MRAs), due to hyperkalemia, may be improved by potassium binders. OBJECTIVES: This prespecified analysis of the phase 3 DIAMOND (Patiromer for the Management of Hyperkalemia in Subjects Receiving RAASi Medications for the Treatment of Heart Failure) trial assessed the effect of patiromer in patients with HFrEF and either current or past hyperkalemia. METHODS: Patients with HFrEF and current or past (within 1 year before enrollment) hyperkalemia (serum potassium [sK+] >5.0 mmol/L) entered a single-blind, run-in phase to optimize RAASis while receiving patiromer. They were subsequently randomized, double-blind, to continue patiromer or change to placebo. RESULTS: Of the 1,038 patients who completed run-in, 354 (83.9%) of 422 with current hyperkalemia and 524 (85.1%) of 616 with past hyperkalemia achieved RAASi optimization and were randomized to treatment. During the double-blind phase, patiromer lowered sK+ levels compared with placebo in both the current and past hyperkalemia subgroups: difference in adjusted mean change from baseline: -0.12 (95% CI: -0.17 to -0.07) and -0.08 (95% CI: -0.12 to -0.05), respectively; Pinteraction = 0.166. Patiromer was more effective than placebo in maintaining MRA at target dose in patients with current vs past hyperkalemia (HR: 0.45 [95% CI: 0.26-0.76] vs HR: 0.85 [95% CI: 0.54-1.32]; Pinteraction = 0.031). Adverse events were similar between subgroups. CONCLUSIONS: The use of patiromer facilitates achieving target doses of RAASis in patients with HFrEF with either current or past hyperkalemia. For those with current hyperkalemia before RAASi optimization, use of patiromer may be more beneficial in helping to maintain sK+ control and achieve MRA target dose. (Patiromer for the Management of Hyperkalemia in Subjects Receiving RAASi Medications for the Treatment of Heart Failure [DIAMOND]; NCT03888066).

8.
Polymers (Basel) ; 16(18)2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39339091

ABSTRACT

Lithium-ion batteries (LIBs) are well known for their energy efficiency and environmental benefits. However, increasing their energy density compromises their safety. This study introduces a novel ceramic-coated separator to enhance the performance and safety of LIBs. Electrospinning was used to apply a coating consisting of an alumina (Al2O3) ceramic and polyacrylic acid (PAA) binder to a polypropylene (PP) separator to significantly improve the mechanical properties of the PP separator and, ultimately, the electrochemical properties of the battery cell. Tests with 2032-coin cells showed that the efficiency of cells containing separators coated with 0.5 g PAA/Al2O3 was approximately 10.2% higher at high current rates (C-rates) compared to cells with the bare PP separator. Open circuit voltage (OCV) tests revealed superior thermal safety, with bare PP separators maintaining stability for 453 s, whereas the cells equipped with PP separators coated with 4 g PAA/Al2O3 remained stable for 937 s. The elongation increased from 88.3% (bare PP separator) to 129.1% (PP separator coated with 4 g PAA/Al2O3), and thermal shrinkage decreased from 58.2% to 34.9%. These findings suggest that ceramic/PAA-coated separators significantly contribute to enhancing the thermal safety and capacity retention of high-energy-density LIBs.

9.
Polymers (Basel) ; 16(18)2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39339090

ABSTRACT

To improve the reinforcement effect between a binder and high solid filler in a propellant formula, grafting the bonding group into the binder to form a neutral polymeric is a practically novel approach to improving the interface properties of the propellant. In this work, a glycidyl azide polyol energetic thermoplastic elastomer binder with a -CN bonding group (GAP-ETPE) was synthesized, and the mechanical and thermal decomposition mechanism of GAP-ETPE with Hexogeon (RDX) model propellants were studied. The stress-strain results indicated that the tensile strength and strain of GAP-ETPE/RDX model propellants were 6.43 MPa and 32.1%, respectively. DMA data showed that the storage modulus (E') of the GAP-ETPE/RDX model propellants could increase the glass transition temperature (Tg) values, those were shifted to higher temperature with the increase in filler RDX percentages. TG/DTG showed the four decomposition stages of the decomposition process of the GAP-ETPE/RDX model propellants, and the thermal decomposition equation was constructed. These efforts provide a novel method to improve GAP-ETPE/RDX propellants mechanical property, and the thermal decomposition behavior of GAP-ETPE/RDX propellants also provided technical support for the study of propellant combustion characteristics.

10.
Can J Kidney Health Dis ; 11: 20543581241273998, 2024.
Article in English | MEDLINE | ID: mdl-39290404

ABSTRACT

Rationale: Sucroferric oxyhydroxide is an iron-based phosphate-binding medication that has been approved for the treatment of hyperphosphatemia in patients with end-stage kidney disease. Given the low overall iron release from the polynuclear iron(III)-oxyhydroxide molecule, recommendations regarding its use prior to colonoscopy/sigmoidoscopy have not been developed. Presenting concerns of the patient: A 51-year-old male with a known history of end-stage renal disease treated with hemodialysis was referred to Gastroenterology for consideration of colonoscopy to rule out malignancy because of a history of rectal bleeding. This was to be completed prior to proceeding with a living-donor kidney transplant. Diagnoses: Flexible sigmoidoscopy done after non-diagnostic colonoscopy demonstrated diffuse "charcoal-like" material that prevented adequate visualization of the bowel despite standard bowel preparation. The findings were believed to be secondary to the use of sucroferric oxyhydroxide prescribed for hyperphosphatemia. Interventions: The patient was subsequently instructed to discontinue sucroferric oxyhydroxide for 2 weeks prior to his repeat sigmoidoscopy procedure. Outcomes: The patient's repeat sigmoidoscopy after discontinuing sucroferric oxyhydroxide allowed for adequate bowel visualization that revealed only a benign lipoma. Teaching Points: This case demonstrates the potential for sucroferric oxyhydroxide use to result in poor bowel preparation and resulting inadequate visualization on lower gastrointestinal endoscopy. It serves to highlight the clinical implications leading to the need for repeated procedures, which contributes to resource waste and unnecessary costs to the healthcare system, as well as delays in diagnostic evaluation required for transplantation; patient frustration was evident.


Justification: L'oxyhydroxyde sucro-ferrique, un médicament à base de fer liant le phosphate, a été approuvé pour le traitement de l'hyperphosphatémie chez les patients atteints d'insuffisance rénale terminale. La molécule polynucléaire fer (lll) ­ oxyhydroxyde ne libérant qu'une faible quantité globale de fer, aucune recommandation n'a été développée concernant son utilisation avant une coloscopie/sigmoïdoscopie. Présentation du cas: Un homme de 51 ans connu pour insuffisance rénale terminale et traité par hémodialyse a été orienté en gastroentérologie pour subir une coloscopie afin d'exclure une tumeur maligne en raison d'antécédents de saignement rectal. L'examen devait être complété avant de procéder à la greffe de rein par donneur vivant. Diagnostic: Une sigmoïdoscopie souple réalisée après une coloscopie non diagnostique a révélé une matière diffuse de type « charbon de bois ¼ qui empêchait de bien voir l'intestin malgré une préparation intestinale adéquate. Ce résultat a été jugé secondaire à l'utilisation d'oxyhydroxyde sucro-ferrique prescrit pour traiter l'hyperphosphatémie. Intervention: On a demandé au patient d'interrompre le traitement par oxyhydroxyde sucro-ferrique pendant deux semaines avant de répéter la procédure de sigmoïdoscopie. Résultats: La sigmoïdoscopie répétée après l'arrêt de l'oxyhydroxyde sucroferrique a permis une visualisation adéquate de l'intestin qui n'a révélé qu'un lipome bénin. Enseignements tirés: Ce cas démontre que l'utilisation d'oxyhydroxyde sucro-ferrique peut entraîner une mauvaise préparation intestinale et entraver la visualisation lors d'une endoscopie gastro-intestinale basse. Il met en évidence les répercussions cliniques qui justifient des procédures répétées, lesquelles contribuent au gaspillage des ressources et entraînent des coûts inutiles pour le système de santé, ainsi que les retards dans l'évaluation diagnostique requise pour la transplantation; dans ce cas, la frustration du patient était évidente.

11.
Int J Mol Sci ; 25(17)2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39273614

ABSTRACT

Alzheimer's disease is the most common form of dementia, characterized by the pathological accumulation of amyloid-beta (Aß) plaques and tau neurofibrillary tangles. Triggering receptor expressed on myeloid cells 2 (TREM2) is increasingly recognized as playing a central role in Aß clearance and microglia activation in AD. The TREM2 gene transcriptional product is alternatively spliced to produce three different protein isoforms. The canonical TREM2 isoform binds to DAP12 to activate downstream pathways. However, little is known about the function or interaction partners of the alternative TREM2 isoforms. The present study utilized a computational approach in a systematic search for new interaction partners of the TREM2 isoforms by integrating several state-of-the-art structural bioinformatics tools from initial large-scale screening to one-on-one corroborative modeling and eventual all-atom visualization. CD9, a cell surface glycoprotein involved in cell-cell adhesion and migration, was identified as a new interaction partner for two TREM2 isoforms, and CALM, a calcium-binding protein involved in calcium signaling, was identified as an interaction partner for a third TREM2 isoform, highlighting the potential role of cell adhesion and calcium regulation in AD.


Subject(s)
Alternative Splicing , Alzheimer Disease , Membrane Glycoproteins , Protein Binding , Protein Isoforms , Receptors, Immunologic , Membrane Glycoproteins/metabolism , Membrane Glycoproteins/genetics , Humans , Receptors, Immunologic/metabolism , Receptors, Immunologic/genetics , Protein Isoforms/metabolism , Protein Isoforms/genetics , Alzheimer Disease/metabolism , Alzheimer Disease/genetics , Computational Biology/methods
12.
Theranostics ; 14(14): 5371-5387, 2024.
Article in English | MEDLINE | ID: mdl-39310112

ABSTRACT

Somatostatin type 2 receptor (SSTR2) radionuclide therapy using ß- particle-emitting radioligands has entered clinical practice for the treatment of neuroendocrine neoplasms (NENs). Despite the initial success of [177Lu]Lu­DOTA-TATE, theranostic SSTR2 radioligands require improved pharmacokinetics and enhanced compatibility with alternative radionuclides. Consequently, this study evaluates the pharmacokinetic effects of the albumin-binding domain cLAB4 on theranostic performance of copper­67-labeled NODAGA-TATE variants in an SSTR2-positive mouse pheochromocytoma (MPC) model. Methods: Binding, uptake, and release of radioligands as well as growth-inhibiting effects were characterized in cells grown as monolayers and spheroids. Tissue pharmacokinetics, absorbed tumor doses, and projected human organ doses were determined from quantitative SPECT imaging in a subcutaneous tumor allograft mouse model. Treatment effects on tumor growth, leukocyte numbers, and renal albumin excretion were assessed. Results: Both copper­64- and copper­67-labeled versions of NODAGA-TATE and NODAGA-cLAB4­TATE showed similar SSTR2 binding affinity, but faster release from tumor cells compared to the clinical reference [177Lu]Lu­DOTA-TATE. The bifunctional SSTR2/albumin-binding radioligand [67Cu]Cu­NODAGA-cLAB4­TATE showed both an improved uptake and prolonged residence time in tumors resulting in equivalent treatment efficacy to [177Lu]Lu­DOTA-TATE. Absorbed doses were well tolerated in terms of leukocyte counts and kidney function. Conclusion: This preclinical study demonstrates therapeutic efficacy of [67Cu]Cu­NODAGA-cLAB4­TATE in SSTR2-positive tumors. As an intrinsic radionuclide theranostic agent, the radioligand provides stable radiocopper complexes and high sensitivity in SPECT imaging for prospective determination and monitoring of therapeutic doses in vivo. Beyond that, copper­64- and copper­61-labeled versions offer possibilities for pre- and post-therapeutic PET. Therefore, NODAGA-cLAB4-TATE has the potential to advance clinical use of radiocopper in SSTR2-targeted cancer theranostics.


Subject(s)
Copper Radioisotopes , Heterocyclic Compounds, 1-Ring , Radiopharmaceuticals , Receptors, Somatostatin , Animals , Receptors, Somatostatin/metabolism , Mice , Radiopharmaceuticals/pharmacokinetics , Radiopharmaceuticals/pharmacology , Radiopharmaceuticals/therapeutic use , Humans , Albumins , Cell Line, Tumor , Pheochromocytoma/radiotherapy , Pheochromocytoma/diagnostic imaging , Pheochromocytoma/metabolism , Acetates/chemistry , Theranostic Nanomedicine/methods , Tissue Distribution , Female , Disease Models, Animal
13.
Environ Pollut ; 362: 124954, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39277127

ABSTRACT

The Volatile Organic Compounds (VOCs) in asphalt fume is widely concerned currently due to its biological toxicity, while the negative effects by asphalt Gaseous Inorganic Compounds (GICs) have not been well quantified and addressed yet. The study investigated the thermodynamic characteristics of base and modified asphalt binders during the multiple phases of releasing the GICs, then the releasing amounts and concentrations of GICs were quantified by fume analyzer. Meanwhile, the environmental impacts of GICs from 4 kinds of asphalt binders have been quantified and interpreted. The results showed that the modified asphalt released less proportion of GICs than base asphalt as heated by same thermal condition according to the TG-DTG and enthalpy analysis. Considering 1 g of asphalt sample, the base asphalt could release extra 8 mg of GICs than modified asphalt, additionally, the emissions of NO2, NO, CO2, and SO2 are all less than the mass of 1 mg. For the environmental effects, the releasing GICs had the greatest impacts on human toxicity due to the intensive CO emission. These results are expected to provide reference and new insights into the improvement of asphalt fumes mitigation.

14.
Foods ; 13(17)2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39272429

ABSTRACT

Modernization has led to a large convenience food market, and the demand for freeze-dried (FD) soup products is increasing in the Republic of Korea. FD soup products are easy to eat without cooking and can be stored for long periods. However, it is often difficult to ensure sensory satisfaction after rehydration of FD soup products; in particular, the ingredients are not evenly dispersed. Therefore, a stable dispersion or reconstitution of the FD soup products is required after rehydration. Here, the effects of high-speed shearing homogenization on the physical properties of a carbohydrate-binder mixture comprising maltodextrin, potato starch, and rice flour were investigated during hydrothermal gelatinization. To find a suitable treatment condition, different homogenization eras, speeds, and concentrations of the binder mixture were considered; in particular, the homogenization eras were set by considering the hydrothermal property of the binder mixture profiled using differential scanning calorimetry. The viscosity of the binder mixture and the compression strength and microstructure of the FD binder block, including the dispersion stability after rehydration, were evaluated. The quality of the FD binder block was improved by homogenization above 5000 rpm when the core temperature of the binder mixture reached approximately To at 14.5-21.8% concentrations. The improved FD binder block exhibited a fine surface and tiny porous microstructure compared with the control (with continuous agitation at 250 rpm). The control block was divided into two phases, whereas the improved block maintained the initial dispersion stability at 50 °C for 1 h. These results are expected to be referenced for the purpose of improving the quality of the FD soup products.

15.
Sci Rep ; 14(1): 20960, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39251860

ABSTRACT

The stone waste generated by stone industry occupy land resources, cause safety hazards and need to be efficiently resourcefully utilized. In this study, the CGF solid waste based binder (abbreviated as CGF) with calcium carbide residue (CCR), ground granulated blast furnace slag (GGBS), and fly ash (FA) as components was developed to solidify the stone waste. Through "treating waste with waste", the resource utilization of solid waste was realized. The mechanical properties and reaction mechanism of CGF solidified stone waste were investigated through unconfined compressive strength (UCS), XRD, and SEM-EDS tests. The results show that CGF has the better solidify effect on stone waste, and its strength meets the requirements of the road base material standards. Compared to cement, the CGF solidified stone waste existed higher UCS at both 7 and 28 d of curing. The UCS of CGF solidified stone waste reaches 2.93 and 4.42 MPa under curing of 7 and 28 d at 5% binder content, which is 1.61 and 1.37 times higher that of P.O. 42.5 cement. Furthermore, the primary mineral-based stone wastes will not react with the binder, and the CGF generates gelling products such as C-S-H C-A-H, and C-A-S-H through alkali-activated reactions between the components of CGF. These gelling products enhance the UCS of solidified stone wastes through cementing and filling effects. The findings provide a feasible approach with low-carbon emission and low-cost for resourceful utilization of stone wastes.

16.
Adv Sci (Weinh) ; : e2408544, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39229933

ABSTRACT

Binder plays a crucial role in constructing high-performance electrodes for water electrolysis. While most research has been focused on advancing electrocatalysts, the application of binders in electrode design has yet to be fully explored. Herein, the in situ incorporation of polytetrafluoroethylene (PTFE) as a multifunctional binder, which increases electrochemical active sites, enhances mass transfer, and strengthens the mechanical and chemical robustness of oxygen evolution reaction (OER) electrodes, is reported. The NiFe-LDH@PTFE/NF electrode prepared by co-deposition of PTFE with NiFe-layered double hydroxide onto nickel foam demonstrates exceptional long-term stability with a minimal potential decay rate of 0.034 mV h-1 at 500 mA cm-2 for 1000 h. The alkaline water electrolyzer utilizing NiFe-LDH@PTFE/NF requires only 1.584 V at 500 mA cm-2 and sustains high energy efficiency over 1000 h under industrial operating conditions. This work opens a new path for stabilizing active sites to obtain durable electrodes for OER as well as other electrocatalytic systems.

17.
J Colloid Interface Sci ; 678(Pt A): 1031-1042, 2024 Aug 31.
Article in English | MEDLINE | ID: mdl-39236432

ABSTRACT

Cost-efficient material with an ingenious design is important in the engineering applications of flexible energy storage and electromagnetic (EM) protection. In this study, bimetallic ZnCo2S4 (ZCS) polyhedral nanoparticles homogenously embedded in the surface of porous N-doped carbon nanofiber membranes (ZCS@PCNFM) have been fabricated by electrospinning technique combined with carbonization and hydrothermal processes. As a self-assembled electrode for lithium-ion batteries (LIBs), the bimetallic ZCS nanoparticles possess rich redox reactions, good electrical conductivity, and pseudocapacitive properties, while the three-dimensional (3D) multiaperture architecture of the nanofiber film not only shortens the transfer spacing of lithium ions and electrons but also effectively tolerates the volume variation during lithiation and delithiation cycles. Benefiting from the above merits, the ZCS@PCNFM electrode exhibits good cycle performance (662.3 mA h/g at 100 mA/g after 100 cycles), superior rate capacity (401.3 mA h/g at 1 A/g) and an extremely high initial specific capacity of 1152.2 mAh/g at 100 mA/g. Meanwhile, depending on the hierarchical nanostructure and multi-component heterogeneous interface effects constructed by 3D inlaid architecture, the ZCS@PCNFM nanocomposite exhibits fascinating microwave absorption (MA) characteristics with a superhigh reflection loss (RL) of -49.7 dB at a filling content of only 20 wt% and corresponding effective absorption bandwidth (EAB, RL<-10 dB) of 5.2 GHz ranging from 12.8 to 18.0 GHz at 2.2 mm.

18.
Polymers (Basel) ; 16(17)2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39274179

ABSTRACT

Metal Fused Filament Fabrication provides a simple and cost-efficient way to produce dense metal parts with a homogenous microstructure. However, current limitations include the use of hazardous and expensive organic solvents during debinding for flexible filaments the stiffness of filaments made from partly water-soluble binder systems. In this study, the influence of various additives on different partly water-soluble binder systems, with regard to the flexibility and properties of the final parts, was investigated. Furthermore, a method using dynamic mechanical analysis to quantify the flexibility of filaments was introduced and successfully applied. For the first time, it was possible to produce flexible, partly water-soluble filaments with 60 vol.% solid content, which allowed the 3D printing of complex small and large parts with a high level of detail. After sintering, density values of up to 98.9% of theoretical density were achieved, which is significantly higher than those obtained with existing binder systems.

19.
Materials (Basel) ; 17(17)2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39274613

ABSTRACT

High-entropy alloys (HEA) as a kind of new binder for cemented carbide have garnered significant attention. In this work, WC/(17~25 wt.%)Al0.5CoCrFeNiTi0.5 cemented carbides were prepared by hot pressing sintering (HPS), and the reactions between WC powder and Al0.5CoCrFeNiTi0.5 powder during hot pressing sintering were elucidated. It found that different from traditional Co binder, the Al0.5CoCrFeNiTi0.5 binder effectively inhibited WC grain growth. During HPS, the decomposed W and C atoms from WC diffused into the Al0.5CoCrFeNiTi0.5 binder, reacted with the elements in the binder, and then formed the M(Co, Fe, Ni)3W3C phase. The back-diffusion of W and C atoms to WC grains was restricted by the Al0.5CoCrFeNiTi0.5 alloy and inhibited them from re-precipitating onto the large undissolved WC grains. As a result, the average size of WC grains in the cemented carbides was less than 200 nm. This work bright new insight into the grain refinement mechanisms of WC cemented carbide with HEA binder and provide a guidance for designing performance-stable WC/HEA cemented carbide and promoting their application.

20.
Materials (Basel) ; 17(17)2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39274647

ABSTRACT

The regeneration performance of an aged styrene-butadiene-styrene block copolymer (SBS) will be significantly influenced by different rejuvenators. The objective of this study was to comparatively investigate the regeneration effect of different SBS-modified asphalt regenerators on aged SBS-modified asphalt. Four types of different regenerant formulations were selected. The optimal rejuvenator content was determined firstly using conventional performance tests. The rheological properties of the aged SBS-modified asphalt binder were evaluated by multiple stress creep recovery (MSCR) experiments. Subsequently, the regeneration mechanism of the SBS-modified asphalt binder was investigated using thin-layer chromatography-flame ionization detection (TLC-FID) and Fourier transform infrared spectroscopy (FTIR). The results showed that the rejuvenator had a certain recovery effect on the penetration, softening point, and ductility of the SBS-modified asphalt binder after aging. The SBS-modified rejuvenating agent was the most favorable among the four types of rejuvenators, where a rejuvenator dosage of 12% showed the optimal rejuvenation effect. The addition of regenerators could appropriately improve the elastic deformation capacity of the aged asphalt binder. The epoxy soybean oil in the regenerant reacted with the aging SBS-modified asphalt binder, supplementing the lost oil in the aged SBS-modified asphalt binder, dispersing the excessive accumulation of asphaltene, and making the residual SBS swell again. The viscoelastic properties of the aging asphalt binder were improved by adjusting the content of components and functional groups to achieve the purpose of regeneration.

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