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In this report, we introduce a novel idea to prepare a redox additive in a gel polymer electrolyte system of PVA-ZnSO4-H2SO4 based on zinc-carbon battery recycling. Here, zinc cans from spent zinc-carbon batteries are dissolved completely in 1 M H2SO4 to obtain a redox additive in an aqueous electrolyte of ZnSO4-H2SO4. Moreover, carbon nanoparticles and graphene nanosheets were synthesized from carbon rod and carbon powder from spent zinc-carbon batteries by only one step of washing and electrochemical exfoliation, respectively, which have good electrochemical capability. The three-electrode system using a ZnSO4-H2SO4 electrolyte with carbon nanoparticles and graphene nanosheets as working electrodes shows high electrochemical adaptability, which points out its promising application in supercapacitor devices. Thus, the symmetrical solid-state supercapacitor devices based on the sandwich structure of graphene nanosheets/PVA-ZnSO4-H2SO4/graphene nanosheets illustrated the highest energy density of 39.17 W h kg-1 at a power density of 1700 W kg-1. While symmetrical devices based on carbon nanoparticles/PVA-ZnSO4-H2SO4/carbon nanoparticles exhibited a maximum energy density of 35.65 W h kg-1 at a power density of 1700 W kg-1. Moreover, these devices illustrate strong durability after 5000 cycles, with approximately 90.2% and 73.1% remaining, respectively. These results provide a promising strategy for almost completely recycling zinc-carbon batteries, one of the most popular dry batteries.
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In this paper, carbon materials, including graphene nanosheets and carbon nanoparticles, were prepared from spent zinc-carbon batteries by the following two simple methods: electrochemical exfoliation and ultrasonication. Here, graphene nanosheets were synthesized by electrochemical exfoliation in 0.5 M H2SO4 by using a direct current power supply with two carbon rods from spent zinc-carbon batteries. Carbon nanoparticles were prepared by fast ultrasonication in a low-cost, green solution of DI water and ethanol. Graphene nanosheets in this study have high quality, large scale, and good electrochemical ability, while carbon nanoparticles have a unique nanosize and a good specific surface area. These carbon materials were applied for electrochemical measurements for supercapacitor studies and showed excellent stability at different temperatures. Moreover, electric double-layer capacitor devices based on graphene nanosheets and carbon nanoparticles were also used in electrochemical studies with strong stability and good electrochemical capability.
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In a recent paper in this journal (RSC Med. Chem., 2023, 14, 2429), we described an unusually strong impact of regiospecific exchange of phenylalanines by tyrosines in 10 gallium-68-labeled trimers of certain cyclic RGD peptides, c[XRGDLAXp(NMe)K] (X = F or Y), on non-specific organ uptakes. We found that there was, in part, no correlation of liver uptake with established polarity proxies, such as the octanol-water distribution coefficient (log D). Since this observation could not be explained straightforwardly, we suggested that the symmetry of the compounds had resulted in a synergistic interaction of certain components of the macromolecules. In the present work, we investigated whether a comparable effect also occurred for a series of 5 tetramers labeled with lutetium-177. We found that in contrast to the trimers, liver uptake of the tetramers was well correlated to their polarity, indicating that the unusual observations along the trimer series indeed was a unique feature, probably related to their particular symmetry. Since the Lu-177 labeled tetramers are also potential agents for treatment of a variety of αvß6-integrin expressing cancers, these were evaluated in mice bearing human lung adenocarcinoma xenografts. Due to their tumor-specific uptake and retention in biodistribution and SPECT imaging experiments, these compounds are considered a step forward on the way to αvß6-integrin-targeted anticancer agents. Furthermore, we noticed that the presence of tyrosines in general had a positive impact on the in vivo performance of our peptide multimers. In view of the fact that a corresponding rule was already proposed in the context of protein engineering, we argue in favor of considering peptide multimers as a special class of small or medium-sized proteins. In summary, we contend that the performance of peptide multimers is less determined by the in vitro characteristics (particularly, affinity and selectivity) of monomers, but rather by the peptides' suitability for the overall macromolecular design concept, and peptides containing tyrosines are preferred.
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PURPOSE: 68Ga-Trivehexin is an investigational PET radiopharmaceutical (NCT05799274) targeting αvß6-integrin for PET imaging of carcinomas. 177Lu-D0301 is a structurally related therapeutic peptide tetramer. However, it showed considerable kidney uptake in rodents, impeding clinical applicability. We therefore evaluated the impact of different kidney protection strategies on the biodistribution of both agents in normal and tumor-bearing mice. METHODS: Ex-vivo biodistribution of 68Ga-Trivehexin (90 min p.i.) and 177Lu-D0301 (90 min and 24 h p.i.) was determined in healthy C57BL/6N and H2009 (human lung adenocarcinoma) xenografted CB17-SCID mice without and with co-infusion of 100 µL of solutions containing 2.5% arginine + 2.5% lysine (Arg/Lys), 4% succinylated gelatin (gelofusine, gelo), or combinations thereof. Arg/Lys was injected either i.p. 30 min before and after the radiopharmaceutical, or i.v. 2 min before the radiopharmaceutical. Gelo was administered either i.v. 2 min prior activity, or pre-mixed and injected together with the radiopharmaceutical (n = 5 per group). C57BL/6N mice were furthermore imaged by PET (90 min p.i.) and SPECT (24 h p.i.). RESULTS: Kidney uptake of 68Ga-Trivehexin in C57BL/6N mice was reduced by 15% (Arg/Lys i.p.), 25% (Arg/Lys i.v.), and 70% (gelo i.v.), 90 min p.i., relative to control. 177Lu-D0301 kidney uptake was reduced by 2% (Arg/Lys i.p.), 41% (Arg/Lys i.v.), 61% (gelo i.v.) and 66% (gelo + Arg/Lys i.v.) 24 h p.i., compared to control. Combination of Arg/Lys and gelo provided no substantial benefit. Gelo furthermore reduced kidney uptake of 177Lu-D0301 by 76% (90 min p.i.) and 85% (24 h p.i.) in H2009 bearing SCID mice. Since tumor uptake was not (90 min p.i.) or only slightly reduced (15%, 24 h p.i.), the tumor/kidney ratio was improved by factors of 3.3 (90 min p.i.) and 2.6 (24 h p.i.). Reduction of kidney uptake was demonstrated by SPECT, which also showed that the remaining activity was located in the cortex. CONCLUSIONS: The kidney uptake of both investigated radiopharmaceuticals was more efficiently reduced by gelofusine (61-85%) than Arg/Lys (25-41%). Gelofusine appears particularly suitable for reducing renal uptake of αvß6-integrin targeted 177Lu-labeled peptide multimers because its application led to approximately three times higher tumor-to-kidney ratios. Since the incidence of severe adverse events (anaphylaxis) with succinylated gelatin products (reportedly 0.0062-0.038%) is comparable to that of gadolinium-based MRI or iodinated CT contrast agents (0.008% and 0.04%, respectively), clinical use of gelofusine during radioligand therapy appears feasible if similar risk management strategies as for contrast agents are applied.
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Gelatina , Integrinas , Rim , Animais , Camundongos , Rim/metabolismo , Rim/diagnóstico por imagem , Distribuição Tecidual , Humanos , Integrinas/metabolismo , Gelatina/química , Compostos Radiofarmacêuticos/farmacocinética , Marcação por Isótopo , Linhagem Celular Tumoral , Radioisótopos de Gálio , Aminoácidos/química , Aminoácidos/farmacocinética , Transporte Biológico , Peptídeos/farmacocinética , Peptídeos/química , Segurança , Camundongos Endogâmicos C57BL , Lutécio , Tomografia por Emissão de Pósitrons , Antígenos de Neoplasias , Radioisótopos , SuccinatosRESUMO
All-solid-state lithium batteries (ASSLBs) using solid polymer electrolytes (SPEs) are believed to be future next-generation batteries aiming to replace high-risk traditional batteries using liquid electrolytes, which have a wide application range in portable electronic devices, portable power supplies, and especially in electric vehicles. Moreover, the appearance of SPEs can overcome the electrolyte leakage and flammability problems in conventional lithium-ion batteries. Nevertheless, ASSLBs still face some limitations due to the low ionic conductivity of solid-state electrolytes (SSEs) at room temperature and the poor contact electrode/electrolyte interface, which can be solved by suitable strategies. Currently, the research strategies of metal-organic frameworks that can be incorporated into solid polymer electrolytes offer a remarkable method for producing uniform solid polymer electrolytes that have good electrode/electrolyte contact interfaces and high ionic conductivity. Herein, the updates of current studies about metal-organic framework-incorporated composite solid polymer electrolytes are discussed in this mini-review.
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Herein, for the first time, we present two-dimensional (2D) NH4V3O8 nanoflakes as an excellent material for both energy conversion of the hydrogen evolution reaction and storage of supercapacitors by a simple and fast two-step synthesis, which exhibit a completely sheet-like morphology, high crystallinity, good specific surface area, and also stability, as determined by thermogravimetric analysis. The 2D-NH4V3O8 flakes show an acceptable hydrogen evolution performance in 0.5 M H2SO4 on a glassy carbon electrode (GCE) coated with 2D-NH4V3O8, which results in a low overpotential of 314 mV at -10 mA cm-2 with an excellent Tafel slope as low as 90 mV dec-1. So far, with the main focus on energy storage, 2D-NH4V3O8 nanoflakes were found to be ideal for supercapacitor electrodes. The NH4V3O8 working electrode in 1 M Na2SO4 shows an excellent electrochemical capability of 274 F g-1 at 0.5 A g-1 for a maximum energy density of 38 W h kg-1 at a power density as high as 250 W kg-1. Moreover, the crystal structure of 2D-NH4V3O8 is demonstrated by density functional theory (DFT) computational simulation using three functionals, GGA, GGA + U, and HSE06. The simple preparation, low cost, and abundance of the NH4V3O8 material provide a promising candidate for not only energy conversion but also energy-storage applications.
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The aim of this study is to prepare a two-dimensional (2D) WO3·H2O nanostructure assembly into a flower shape with good chemical stability for electrochemical studies of catalyst and energy storage applications. The 2D-WO3·H2O nanoflowers structure is created by a fast and simple process at room condition. This cost-effective and scalable technique to obtain 2D-WO3·H2O nanoflowers illustrates two attractive applications of electrochemical capacitor with an excellent energy density value of 25.33 W h kg-1 for high power density value of 1600 W kg-1 and good hydrogen evolution reaction results (low overpotential of 290 mV at a current density of 10 mA cm-2 with a low Tafel slope of 131 mV dec-1). A hydrogen evolution reaction (HER) study of WO3 in acidic media of 0.5 M H2SO4 and electrochemical capacitor (supercapacitors) in 1 M Na2SO4 aqueous electrolyte (three electrode system measurements) demonstrates highly desirable characteristics for practical applications. Our design for highly uniform 2D-WO3·H2O as catalyst material for HER and active material for electrochemical capacitor studies offers an excellent foundation for design and improvement of electrochemical catalyst based on 2D-transition metal oxide materials.
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In this study, we provide a simple and green approach to recycle waste zinc carbon batteries for making carbon dots and porous carbon material. The carbon dots are easily synthesized by one green step, the hydrothermal treatment of a carbon rod in a mixture of DI water and pure ethanol to obtain a blue fluorescence under UV light, which can be used directly as a fluorescence ink. The as-prepared carbon dot process give typical dots with a uniform diameter from 3 to 8 nm with a strong slight blue fluorescent. The porous carbon material is also recycled from carbon powder in a waste battery via one green step annealing process without any chemical activation and with a hierarchically porous structure. This porous carbon material is demonstrated as an electrode for symmetrical solid state supercapacitors (SSCs) in a sandwich structure: porous carbon/PVA-KOH/porous carbon. The SSCs using recycled porous carbon electrodes exhibit a good energy density of 4.58 W h kg-1 at a power density of 375 W kg-1 and 97.6% retention after 2000 cycles. The facile one green step of hydrothermal and also that of calcination provide a promising strategy to recycle waste zinc carbon batteries, which transfers the excellent applications.
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Kitchen sea salt or table salt is used every day by cooks as a food seasoning. Here, it is introduced into a gel polymer (poly(vinyl) alcohol (PVA)-table salt) for use as an electrolyte, and an electrode was constructed from graphene nanosheets for use as symmetrical solid-state supercapacitors. The graphene sheets are prepared by a pulse control plasma method and used as an electrode material, and were studied by X-ray diffraction (XRD), Raman spectroscopy, as well as scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). A specific capacitance of 117.6 F g-1 at 5 mV s-1 was obtained in a three electrode system with table sea salt as an aqueous electrolyte. For a symmetrical solid-state supercapacitor: graphene/PVA-table sea salt/graphene gave a good specific capacitance of 31.67 F g-1 at 0.25 A g-1 with an energy density of 6.33 W h kg-1 at a power density of 600 W kg-1, with good charge-discharge stability, which was 87% after 8000 cycles. Thus, the development of table sea salt as an environmentally friendly electrolyte has a good potential for use in energy storage applications.
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Information about the occurrence of polybrominated diphenyl ethers (PBDEs) in indoor dusts from various industrial sectors in Southeast Asia is still scarce. In this study, concentrations and congener-specific profiles of PBDEs were determined in indoor dusts from industrial factories, offices, and houses in northern Vietnam. Levels of Σ8PBDEs were higher in the office dusts (median 270; range 230-300 ng/g) and factory dusts (170; 89-510 ng/g) than in the house dusts (61; 25-140 ng/g). BDE-209 was the most dominant congener, accounting for 27-98% (average 62%) of Σ8PBDEs, suggesting the abundance of products treated with deca-BDE mixtures. Residential, commercial, and industrial activities in the studied locations of this survey were not significant sources of PBDEs as compared to those of informal waste processing activities in Vietnam. Relatively low PBDE concentrations detected in our dust samples partially reflect effectiveness of the global PBDE phase-out. Human exposure and health risk associated with dust-bound PBDEs were estimated, indicating acceptable levels of risk (i.e., neurobehavioral effects). The contributions of workplace dusts in total daily intake doses of PBDEs via dust ingestion were more important for local workers in informal recycling areas than factory workers and general population, raising the need of appropriate labor protection measures.
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Poluição do Ar em Ambientes Fechados , Poeira , Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Exposição Ambiental/análise , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Humanos , Instalações Industriais e de Manufatura , VietnãRESUMO
Sensory conflict among visual, vestibular, and somatosensory information induces vertiginous sensation and postural instability. To elucidate the cognitive mechanisms of the integration between the visual and vestibular cues in humans, we analyzed the cortical hemodynamic responses during sensory conflict between visual and horizontal rotatory vestibular stimulation using a multichannel near-infrared spectroscopy (NIRS) system. The subjects sat on a rotatory chair that was accelerated at 3°/s2 for 20 s to the right or left, kept rotating at 60°/s for 80 s, and then decelerated at 3°/s2 for 20 s. The subjects were instructed to watch white stripes projected on a screen surrounding the chair during the acceleration and deceleration periods. The white stripes moved in two ways; in the "congruent" condition, the stripes moved in the opposite direction of chair rotation at 3°/s2 (i.e., natural visual stimulation), whereas in the "incongruent" condition, the stripes moved in the same direction of chair rotation at 3°/s2 (i.e., conflicted visual stimulation). The cortical hemodynamic activity was recorded from the bilateral temporoparietal regions. Statistical analyses using NIRS-SPM software indicated that hemodynamic activity increased in the bilateral temporoparietal junctions (TPJs) and human MT+ complex, including the medial temporal (MT) area and medial superior temporal (MST) area in the incongruent condition. Furthermore, the subjective strength of the vertiginous sensation was negatively correlated with hemodynamic activity in the dorsal part of the supramarginal gyrus (SMG) in and around the intraparietal sulcus (IPS). These results suggest that sensory conflict between the visual and vestibular stimuli promotes cortical cognitive processes in the cortical network consisting of the TPJ, the medial temporal gyrus (MTG), and IPS, which might contribute to self-motion perception to maintain a sense of balance or equilibrioception during sensory conflict.
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Following photodissociation at 248 nm of gaseous methyl formate (HC(O)OCH3, 0.73 Torr) and Ar (0.14 Torr), temporally resolved vibration-rotational emission spectra of highly internally excited CO (ν ≤ 11, J ≤ 27) in the 1850-2250 cm-1 region were recorded with a step-scan Fourier-transform spectrometer. The vibration-rotational distribution of CO is almost Boltzmann, with a nascent average rotational energy (ER0) of 3 ± 1 kJ mol-1 and a vibrational energy (EV0) of 76 ± 9 kJ mol-1. With 3 Torr of Ar added to the system, the average vibrational energy was decreased to EV0 = 61 ± 7 kJ mol-1. We observed no distinct evidence of a bimodal rotational distribution for ν = 1 and 2, as reported previously [Lombardi et al., J. Phys. Chem. A 2016, 129, 5155], as evidence of a roaming mechanism. The vibrational distribution with a temperature of â¼13000 ± 1000 K, however, agrees satisfactorily with trajectory calculations of these authors, who took into account conical intersections from the S1 state. Highly internally excited CH3OH that is expected to be produced from a roaming mechanism was unobserved. Following photodissociation at 193 nm of gaseous HC(O)OCH3 (0.42 Torr) and Ar (0.09 Torr), vibration-rotational emission spectra of CO (ν ≤ 4, J ≤ 38) and CO2 (with two components of varied internal distributions) were observed, indicating that new channels are open. Quantum-chemical calculations, computed at varied levels of theory, on the ground electronic potential-energy schemes provide a possible explanation for some of our observations. At 193 nm, the CO2 was produced from secondary dissociation of the products HC(O)O and CH3OCO, and CO was produced primarily from secondary dissociation of the product HCO produced on the S1 surface or the decomposition to CH3OH + CO on the S0 surface.