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GeSe, an analogue of SnSe, shows promise in exhibiting exceptional thermoelectric performance in the Pnma phase. The constraints on its dopability, however, pose challenges in attaining optimal carrier concentrations and improving ZT values. This study demonstrates a crystal structure evolution strategy for achieving highly doped samples and promising ZTs in GeSe via LiBiTe2 alloying. A rhombohedral phase (R3m) can be stabilized in the GeSe-LiBiTe2 system, further evolving into a cubic (Fm3Ì m) phase with a rising temperature. The band structures of GeSe-LiBiTe2 in the rhombohedral and cubic phases feature a similar multiple-valley energy-converged valence band of L and Σ bands. The observed high carrier concentration (â¼1020 cm-3) reflects the effective convergence of these bands, enabling a high density-of-states effective mass and an enhanced power factor. Moreover, a very low lattice thermal conductivity of 0.6-0.5 W m-1 K-1 from 300 to 723 K is achieved in 0.9GeSe-0.1LiBiTe2, approaching the amorphous limit value. This remarkably low lattice thermal conductivity is related to phonon scattering from point defects, planar vacancies, and ferroelectric instability-induced low-energy Einstein oscillators. Finally, a maximum ZT value of 1.1 to 1.3 at 723 K is obtained, with a high average ZT value of over 0.8 (400-723 K) in 0.9GeSe-0.1LiBiTe2 samples. This study establishes a viable route for tailoring crystal structures to significantly improve the performance of GeSe-related compounds.
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Ferroptosis has been regarded as a critical event in the process of diffuse large B cell lymphoma (DLBCL). Sentrin-specific protease 1 (SENP1) has emerged as an oncogene in multiple human malignancies. The present work was to investigate the effects of SENP1 on the progression of DLBCL and the possible regulatory mechanism involving ferroptosis. SENP1 expression in DLBCL tissues, parental and cisplatin-resistant DLBCL cells were, respectively, tested by GEPIA database, RT-qPCR, and Western blot. Cell viability was estimated via CCK-8 assay. Flow cytometry analysis estimated cell apoptosis and cycle. Western blot examined the expression of apoptosis-, cell cycle-, and ferroptosis-associated proteins. TBARS assay and BODIPY 581/591 C11 probe measured lipid peroxidation. Related assay kit assessed total iron levels. CCK-8 and flow cytometry evaluated cisplatin resistance. SENP1 expression was raised in DLBCL tissues and cells. SENP1 knockdown reduced cell viability, boosted cell apoptosis, cell cycle arrest, and elevated cisplatin sensitivity in DLBCL. SENP1 depletion drove the ferroptosis of both parental and cisplatin-resistant DLBCL cells and ferroptosis inhibitor Fer-1 reversed the influences of SENP1 inhibition on cell viability, apoptosis, cell cycle, and cisplatin resistance in DLBCL. Anyway, SENP1 absence might facilitate ferroptosis to obstruct the development of DLBCL and cisplatin resistance.
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Apoptose , Pontos de Checagem do Ciclo Celular , Cisplatino , Cisteína Endopeptidases , Resistencia a Medicamentos Antineoplásicos , Ferroptose , Linfoma Difuso de Grandes Células B , Humanos , Cisplatino/farmacologia , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Ferroptose/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Cisteína Endopeptidases/metabolismo , Cisteína Endopeptidases/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular TumoralRESUMO
PURPOSE: To evaluate the prognostic performance of [68Ga]Pentixafor PET/CT at baseline for staging of patients with newly diagnosed multiple myeloma (MM) and to compare it with [18F]FDG PET/CT and the Revised-International Staging System (R-ISS). METHODS: Patients who underwent [68Ga]Pentixafor and [18F]FDG PET/CT imaging were retrospectively included. Patient staging was performed according to the Durie-Salmon PLUS staging system based on [68Ga]Pentixafor PET/CT and [18F]FDG PET/CT images, and the R-ISS. Progression-free survival (PFS) at patient follow-up was estimated using the Kaplan-Meier estimator and compared using the log-rank test. Area under the receiver operating characteristic curve (AUC) was calculated to assess predictive performance. RESULTS: Fifty-five MM patients were evaluated. Compared with [18F]FDG PET, [68Ga]Pentixafor PET detected 25 patients as the same stage, while 26 patients were upstaged and 4 patients were downstaged (P = 0.001). After considering the low-dose CT data, there was no statistically significant difference in the number of patients classified in each stage using [68Ga]Pentixafor PET/CT and [18F]FDG PET/CT (P = 0.091). [68Ga]Pentixafor PET/CT-based staging discriminated PFS outcomes in patients with different disease stages (stage I vs. stage II, stage I vs. stage III, and stage II vs. stage III; all P < 0.05), whereas for [18F]FDG PET/CT, there was only a difference in median PFS between stage I and III (P = 0.021). When staged by R-ISS, the median PFS for stage III was significantly lower than that for stage I and II (P = 0.008 and 0.035, respectively). When predicting 2-year PFS based on staging, the AUC of [68Ga]Pentixafor PET/CT was significantly higher than that of [68Ga]Pentixafor PET (0.923 vs. 0.821, P = 0.002), [18F]FDG PET (0.923 vs. 0.752 P = 0.002), and R-ISS (0.923 vs. 0.776, P = 0.005). CONCLUSIONS: [68Ga]Pentixafor PET/CT-based staging possesses substantial potential to predict disease progression in newly diagnosed MM patients.
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Fluordesoxiglucose F18 , Mieloma Múltiplo , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Masculino , Feminino , Mieloma Múltiplo/diagnóstico por imagem , Pessoa de Meia-Idade , Idoso , Prognóstico , Peptídeos Cíclicos , Adulto , Estudos Retrospectivos , Complexos de Coordenação , Idoso de 80 Anos ou maisRESUMO
GeMnTe2 adopts a cubic rock salt structure and is a promising mid-temperature thermoelectric material. The pair distribution function analysis of neutron total scattering data, however, indicates that GeMnTe2 is locally distorted from the ideal rock salt structure with Ge2+ cations being discordant and displaced â¼0.3 Å off the octahedron center. By alloying GeMnTe2 with SbTe, the carrier concentration can be tuned in GeMnTe2-x%SbTe (x = 15.1), leading to converged multiple broad valence bands and a high Seebeck coefficient of >200 µV K-1 from 300 to 823 K. The system exhibits a large density-of-state effective mass of >10 me and a high weighted mobility of 80 cm2 V-1 s-1, leading to a power factor of 15 µWcm-1 K-2 at 823 K. The composition GeMnTe2-15.1%SbTe exhibits very low lattice thermal conductivity of â¼0.5 Wm-1 K-1 at 823 K, attributed to the combination of off-centering cations in the rock salt structure, Ge/Mn positional disorder, dislocations, and abundant Ge-rich and Mn-rich nanoparticles. A ZT value of â¼1.5 can be achieved for GeMnTe2-15.1%SbTe with a ZTave of 0.96 in the temperature range of 400-823 K.
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Thermoelectric sulfide materials are of particular interest due to the earth-abundant and cost-effective nature of sulfur. Here, we report a new n-type degenerate semiconductor sulfide, AgBiPbS3, which adopts a Fm3Ì m structure with a narrow band gap of â¼0.32 eV. Despite the homogeneous distribution of elements at the scale of micrometer, Ag2S nanoprecipitates with dimensions of several nanometers were detected throughout the matrix. AgBiPbS3 exhibits a low room-temperature lattice thermal conductivity of 0.88 W m-1 K-1, owing to the intrinsic low lattice thermal conductivity of Ag2S and the effective scattering of phonons at nanoprecipitate boundaries. Moreover, compared to AgBiS2, AgBiPbS3 demonstrates a significantly improved weighted mobility of >16 cm2 V-1 s-1 at 300 K, leading to an enhanced PF of 1.6 µW cm-1 K-2 at 300 K. The superior electrical transport in AgBiPbS3 can be attributed to the high valley degeneracy of the L point (the conduction band minimum), which is contributed by the Pb s and Pb p orbitals. Further, Ga doping is found to be effective in modulating the Fermi levels of AgBiPbS3, leading to further enhancement of PF with a PFave of 2.7 µW cm-1 K-2 in the temperature range of 300-823 K. Consequently, a relatively high ZTave of 0.22 and a peak ZT of â¼0.4 at 823 K have been achieved in 3% Ga-doped AgBiPbS3, highlighting the potential of AgBiPbS3 as an n-type thermoelectric sulfide.
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Trichomonas vaginalis (T. vaginalis) infection is one of the most common sexually transmitted infections worldwide and is associated with several complications. However, the paucity of research regarding the prevalence of T. vaginalis infection in the Tibetan area limits control efforts. We aimed to evaluate the prevalence of T. vaginalis infection in the Tibetan area by a comparison with the prevalence of T. vaginalis in Wuhan city and to unveil the potential risk factors in the Tibetan area. This descriptive, cross-sectional study was conducted among adult women attending gynecology outpatient clinics in two public hospitals (one in Shannan city of Tibet and one in Wuhan city) in China in 2020. Data were retrieved from the medical record system and laboratory information management system, including T. vaginalis infection, bacterial vaginosis, and vulvovaginal candidiasis by wet mount microscopy or nucleic acid hybridization of vaginal secretions from patients. The associations of variables associated with T. vaginalis prevalence were quantified by odds ratios with 95% confidence intervals. The overall prevalence rates of T. vaginalis infection in the Tibetan area and Wuhan city were 20.94% and 2.84%, respectively. The statistically significant factors for the higher prevalence of T. vaginalis infection in the Tibetan area included tertiary educational status (AOR: 0.36 [95% CI: 0.16-0.81]), yearly family income > ¥100,000 (AOR: 0.48 [95% CI: 0.26-0.91]), clinical symptoms (AOR: 4.58[95% CI: 2.32-9.04]), and III-IV grade vaginal cleanliness (AOR: 29.71 [95% CI: 3.95-223.56]) in the multivariate logistic analysis. Interventions targeting improved living standards as well as women's educational level and promoting reproductive hygiene habits are recommended to contribute to the reduction in T. vaginalis infection in the Tibetan area.
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Tricomoníase , Vaginite por Trichomonas , Trichomonas vaginalis , Adulto , Humanos , Feminino , Tibet/epidemiologia , Prevalência , Estudos Transversais , Tricomoníase/epidemiologia , Fatores de Risco , Vaginite por Trichomonas/epidemiologia , Vaginite por Trichomonas/diagnósticoRESUMO
RATIONALE & OBJECTIVE: Hematuria is the most typical presentation of immunoglobulin A nephropathy (IgAN); however, its role in disease progression is still controversial. This study aimed to evaluate the association of hematuria and progression of IgAN. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: A cohort of 1,333 patients with IgAN treated at a Chinese referral hospital with a median follow-up of 45 months. PREDICTORS: Microhematuria was evaluated in fresh urine using a fully automated urine particle analyzer (automated method) and urine sediment examination by a skilled examiner (manual method). Hematuria was characterized as a time-varying attribute; namely, average hematuria level was calculated for every 6-month period for each patient during follow-up. Remission was defined as average red blood cell count ≤5/high-power field (manual method) or ≤28 red blood cells/µL (automated method) during the first 6 months of follow-up. OUTCOMES: Composite event of 50% decline in estimated glomerular ï¬ltration rate or development of kidney failure. ANALYTICAL APPROACH: Multivariable cause-specific hazards models to analyze the relationship between hematuria and the composite kidney disease progression event. RESULTS: Time-varying hematuria during follow-up was an independent risk factor for the composite kidney disease progression event (HR, 1.46; 95% CI, 1.13-1.87; P = 0.003). Hematuria remission during the 6 months after diagnosis was associated with a significantly lower rate of the composite kidney disease progression event (HR, 0.41; 95% CI, 0.28-0.61; P < 0.001). A significant interaction was detected between remission of proteinuria and remission of hematuria during the first 6 months (P < 0.001). The association between remission of hematuria and kidney disease progression was detectable (HR, 0.46; 95% CI, 0.32-0.68) within the subpopulation with persistent proteinuria (protein excretion > 1.0 g/d during the first 6 months), but not among patients whose proteinuria had remitted (HR, 0.64; 95% CI, 0.31-1.29; P = 0.2). The 2 techniques for hematuria evaluation were strongly and significantly linearly correlated (r = 0.948; P < 0.001), and results using these 2 methods were consistent. LIMITATIONS: A single-center retrospective study. Proportional hazards regression incorporating time-varying covariates may create time-varying confounding. The predictive value of reductions in hematuria was not directly evaluated. CONCLUSIONS: Level of hematuria was independently associated with kidney disease progression, whereas hematuria remission was associated with improved kidney outcomes in IgAN among patients with persistent proteinuria. Additionally, to monitor IgAN progression, automated methods to evaluate hematuria hold promise as a replacement for manual evaluation of urinary sediment.
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Progressão da Doença , Glomerulonefrite por IGA/diagnóstico , Glomerulonefrite por IGA/epidemiologia , Hematúria/diagnóstico , Hematúria/epidemiologia , Adulto , Estudos de Coortes , Feminino , Seguimentos , Glomerulonefrite por IGA/sangue , Hematúria/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal/sangue , Insuficiência Renal/diagnóstico , Insuficiência Renal/epidemiologia , Estudos RetrospectivosRESUMO
Herein, an interesting light-induced self-assembly behavior from non-photoresponsive gold nanoparticles (Au NPs) was reported. Specifically, a pH-responsive amphiphile SPBwas developed that contained a particular phenylboronic acid moiety and showed excellent surface activity at the neutral and basic conditions, thereby stabilizing Au NPs well. Accordingly, the SPB-functionalized Au NPs showed strong pH dependence that there presented the pH-induced reversible self-assembly behavior. Furthermore, the introduction of a small amount of commercially available photoacid generator named diphenyliodonium nitrate (DIN) into the system could endow it with apparent light-switchable self-assembly behavior. The pH- and light-induced self-assembly behaviors of SPB-functionalized Au NPs in the absence and presence of DIN, respectively, were systematically studied by various techniques including UV-vis spectrum, transmission electron microscope, nuclear magnetic resonance, and Fourier transform infrared spectroscopy, which evidently confirmed that the stimuli-responsive self-assembly was controlled by the hydrogen-bonding interactions between phenylboronic acid moieties. Attributing to the light-induced obvious color change from bright-red to deep purple, the system was applied in particle imprinting successfully.
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We report a new family of multiple responsive fluids based on the single-tailed pyrrolidone surfactants, N-ethyl-2-pyrrolidone N-alkyl amine (C(m)NP, where m = 10, 12, 14, 16, and 18). These surfactants are highly sensitive to solution pH as a result of the presence of the N-amino group in the molecules. Equilibrium surface tension results indicate that both the surface activity and micellization ability of C(m)NPs decrease with the increase of the protonation degree; i.e., they exhibit a higher critical micelle concentration (cmc) and higher surface tension at the cmc (γ(cmc)) at the acidic conditions than those at the basic conditions. The cmc values of C(m)NPs follow the well-known Klevens equation, which decrease linearly with the increase of the hydrocarbon chain length m at a given pH. More importantly, the self-assemblies of C(m)NPs are highly sensitive to pH, CO2, and CuCl2, as identified by turbidity and viscosity. The transitions between vesicles and wormlike micelles are further confirmed by rheology, static and dynamic light scattering (SLS and DLS), cryogenic transmission electron microscopy (cryo-TEM), and nuclear magnetic resonance (NMR) techniques systematically. Although the aggregate transitions induced by different factors are similar, however, the mechanisms are different. The pH- and CO2-induced transitions are attributed to variation in the protonation degree of the N-amino group; however, CuCl2-induced transitions are a result of the formation of C(m)NP and CuCl2 coordination complexes as revealed by two-dimensional (2D) nuclear Overhauser effect spectrometry (NOESY) NMR and ultraviolet-visible (UV-vis) spectra.
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Three groups of pyrrolidinium headgroup-based gemini surfactants of 1,1'-(propane-1,3-diyl)bis(1-alkyl pyrrolidinium) bromide, in categories of symmetric CmC3CmPB (m = 10, 12, 14), dissymmetric CmC3C14PB (m = 10, 12, 14) and CmC3CnPB (m = 8, 10, 12, m + n = 24) surfactants, are studied using equilibrium surface tension, conductivity, fluorescence, and NMR techniques. The importance of the dissymmetry on the micellization has been revealed in detail. The increase in the hydrophobic chain length m for CmC3CmPB and CmC3C14PB or in the dissymmetry (n/m) for CmC3CnPB can strengthen the aggregation ability and surface activity of the surfactants significantly, i.e., a lower critical micelle concentration (cmc) and a lower surface tension at cmc (γcmc). However, the aggregation number at cmc (N*) obeys the opposite variation tendency and it becomes smaller upon increasing m or n/m, due to the formation of premicelles. Thermodynamic results reveal that the contribution of enthalpy (ΔH) to the Gibbs free energy (ΔG) is strengthened by increasing m or n/m during the spontaneous micellization process. Moreover, (1)H NMR results confirm the microenvironment change of the surfactants from polar water to micelles during the micellization, and 2D Noesy NMR spectra suggest that the methylene groups in the ring should adopt a conformation toward the nonpolar micellar core rather than in the polar water.
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Micelas , Pirrolidinas/química , Tensoativos/química , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Estrutura Molecular , TermodinâmicaRESUMO
The structure of organic ligand scaffolds of copper complexes critically affects their electrocatalytic properties toward water oxidation, which is widely regarded as the bottleneck of overall water splitting. Herein, two novel mononuclear Cu complexes, [Cu(dmabpy)](ClO4)2 (1, dmabpy = 6,6'-bis(dimethylaminomethyl)-2,2'-bipyridine) and [Cu(mabpy)](ClO4)2 (2, mabpy = 6,6'-bis(methylaminomethyl)-2,2'-bipyridine), with four-coordinated distorted planar quadrilateral geometry were synthesized and explored as efficient catalysts for electrochemical oxygen evolution in phosphate buffer solution. Interestingly, complex 1 with a tertiary amine group catalyzes water oxidation with lower onset overpotential and better catalytic performance, while complex 2 containing a secondary amine fragment displays much lower catalytic activity under identical conditions. The water oxidation catalytic mechanism of the two complexes is proposed based on the electrochemical test results. Experimental methods indicate that phosphate coordinated on the Cu center of the two complexes inhibits their reaction with substrate water molecules, resulting in lower activity toward water oxidation. Electrochemical tests reveal that the structure of the coordinated nitrogen atom improves the catalytic performance of the Cu complexes by modulating the coordination of phosphate on the Cu center, indicating that a minor alteration of the coordinating nitrogen atom of the ligand has a detrimental effect on the catalytic performance of electrochemical WOCs based on transition metal complexes.
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Color-changing fibers have attracted much attention for their wide applications in camouflage, security warnings, and anti-counterfeiting. The inorganic color-changing material tungsten trioxide (WO3) has been widely investigated for its good stability, controllability, and ease of synthesis. In this study, photochromic alginate fibers (WO3@Ca-Alg) were prepared by incorporating UV-responsive hybrid tungsten trioxide nanoparticles in the fiber production process. The prepared photochromic alginate fibers changed from white to dark blue after 30 min of UV irradiation and returned to their original color after 64 h. It can be seen that WO3@Ca-Alg has the advantage of long color duration. The strength of this fiber reached 2.61 cN/dtex and the limiting oxygen index (LOI) was 40.9 %, which indicates that the fiber exhibited mechanical resistance and flame-retardant properties. After the cross-linking of WO3@Ca-Alg by sodium tetraborate, a new core-shell structure was generated, which was able to encapsulate tungsten trioxide in it, thus reducing the amount of tungsten trioxide loss, and its salt and washing resistance was greatly improved. This photochromic alginate fiber can be mass produced and spun into yarn.
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Retardadores de Chama , Nanopartículas , Tungstênio , Alginatos , ÓxidosRESUMO
In this study, the plasmonic Ag nanoparticles (Ag NPs) were uniformly anchored on the high conductivity Nb2CTx (MXene) nanosheets to construct an Ag/Nb2CTx substrate for surface-enhanced Raman spectroscopy (SERS) detection of polystyrene (PS) nanoplastics. The KI addition (0.15 mol/L), the volume ratio between substrate colloid and nanoplastic suspension (2:1), and the mass ratio of Nb2CTx in substrate (14%) on SERS performance were optimized. The EM hot spots of Ag/Nb2CTx are significantly enlarged and enhanced, elucidated by FDFD simulation. Then, the linear relationship between the PS nanoplastics concentration with three different sizes (50, 300, and 500 nm) and the SERS intensity was obtained (R2 > 0.976), wherein, the detection limit was as low as 10-4 mg/mL for PS nanoplastic. Owing to the fingerprint feature, the Ag/Nb2CTx-14% substrate successfully discerns the mixtures from two-component nanoplastics. Meanwhile, it exhibits excellent stability of PS nanoplastics on different detection sites. The recovery rates of PS nanoplastics with different sizes in lake water ranged from 94.74% to 107.29%, with the relative standard deviation (RSD) ranging from 2.88% to 8.30%. Based on this method, the expanded polystyrene (EPS) decomposition behavior was evaluated, and the PS concentrations in four water environments were analyzed. This work will pave the way for the accurate quantitative detection of low concentration of nanoplastics in aquatic environments.
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The electroreduction of nitrate to ammonia via a selective eight-electron transfer nitrate reduction reaction offers a promising, low energy consumption, pollution-free, green NH3 synthesis strategy alternative to the Haber-Bosch method. However, it remains a great challenge to achieve high NH4+ selectivity and complete conversion from NO3--N to NH4+-N. Herein, we report ingredients adjustable Cu2O@CoO yolk-shell nanocubes featured with tunable inner void spaces and diverse activity centers, favoring the rapid cascade conversion of NO3- into NO2- on Cu2O and NO2- into NH4+ on CoO. Cu2O@CoO yolk-shell nanocubes exhibit super NH4+ Faradaic efficiencies (>99%) over a wide potential window (-0.2 V to -0.9 V versus RHE) with a considerable NH4+ yield rate of 15.27 mg h-1 cm-2 and fantastic cycling stability and long-term chronoamperometric durability. Cu2O@CoO yolk-shell nanocubes exhibited glorious NO3--N to NH4+-N conversion efficiency in both dilute (500 ppm) and highly concentrated (0.1 and 1 M) NO3- electrolytes, respectively. The nitrate electrolysis membrane electrode assembly system equipped with Cu2O@CoO yolk-shell nanocubes delivers over 99.8% NH4+ Faradaic efficiency at cell voltages of 1.9-2.3 V.
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A stable anode-free lithium metal battery (AFLMB) is accomplished by the adoption of a facile fabricated amorphous antimony (Sb)-coated separator (SbSC). The large specific surface area of the separator elevates lithium (Li)-Sb alloy kinetic, improving Li wetting ability on pristine copper current collector (Cu). When tested with LiNi0.8 Mn0.1 Co0.1 O2 (NMC811) as cathode, the full cell with SbSC demonstrates low nucleation overpotential with compact, dendrite-free and homogeneous Li plating, and exhibits a notable lithium inventory retention rate (LIRR) of 99.8 % with capacity retention of 93.6 % after 60 cycles at 0.5â C-rate. Conversely, full cells containing pristine separator/Cu (i. e., SC) and pristine separator/Sb-coated current collector (i. e., SSbC) display poor cycling performances with low LIRRs. Density functional theory corroborates the nucleation behaviours observed during in-situ half-cell Li deposition. Functionalizing polymeric separator by metallic coating in AFLMB is a novel approach in improving the cycle life of an AFLMB by promoting homogeneous Li plating behavior. This innovative approach exemplifies a promising applicability for uniform Li-plating behavior to achieve a longer cycle life in AFLMB.
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Electrocatalytic nitrate (NO3-) reduction reaction (eNO3-RR) to ammonia under ambient conditions is deemed a sustainable route for wastewater treatment and a promising alternative to the Haber-Bosch process. However, there is still a lack of efficient electrocatalysts to achieve high NH3 production performance at wastewater-relevant low NO3- concentrations. Herein, we report a Pd74Ru26 bimetallic nanocrystal (NC) electrocatalyst capable of exhibiting an average NH3 FE of â¼100% over a wide potential window from 0.1 to -0.3 V (vs. reversible hydrogen electrode, RHE) at a low NO3- concentration of 32.3 mM. The average NH3 yield rate at -0.3 V can reach 16.20 mg h-1 cm-2. Meanwhile, Pd74Ru26 also demonstrates excellent electrocatalytic stability for over 110 h. Experimental investigations and density functional theory (DFT) calculations suggest that the electronic structure modulation between Pd and Ru favors the optimization of NO3- transport with respect to single components. Along the *NO3 reduction pathway, the synergy between Pd and Ru can also lower the energy barrier of the rate-determining steps (RDSs) on Ru and Pd, which are the protonation of *NO2 and *NO, respectively. Finally, this unique alloying design achieves a high-level dynamic equilibrium of adsorption and coupling between *H and various nitrogen intermediates during eNO3-RR.
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GeTe is a promising p-type material with increasingly enhanced thermoelectric properties reported in recent years, demonstrating its superiority for mid-temperature applications. In this work, the thermoelectric performance of GeTe is improved by a facile composite approach. We find that incorporating a small amount of boron particles into the Bi-doped GeTe leads to significant enhancement in power factor and simultaneous reduction in thermal conductivity, through which the synergistic modulation of electrical and thermal transport properties is realized. The thermal mismatch between the boron particles and the matrix induces high-density dislocations that effectively scatter the mid-frequency phonons, accounting for a minimum lattice thermal conductivity of 0.43 Wm-1K-1 at 613 K. Furthermore, the presence of boron/GeTe interfaces modifies the interfacial potential barriers, resulting in increased Seebeck coefficient and hence enhanced power factor (25.4 µWcm-1K-2 at 300 K). Consequently, we obtain a maximum figure of merit Zmax of 4.0 × 10-3 K-1 at 613 K in the GeTe-based composites, which is the record-high value in GeTe-based thermoelectric materials and also superior to most of thermoelectric systems for mid-temperature applications. This work provides an effective way to further enhance the performance of GeTe-based thermoelectrics.
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Objective: To analyse the research history, development trends and current status of relevant literature in the field of Kawasaki disease, and to provide the basis for future directions in Kawasaki disease (KD) research. Methods: Literature on Kawasaki disease published between January 1974 and December 2022 was searched for in the Web of Science database, and CiteSpace was used to perform visual analyses. Results: The search yielded a total of 6950 articles. The number of publications related to Kawasaki disease showed an increasing trend. A collaborative network analysis revealed that the United States, Japan and mainland China were the most influential countries in this field. The University of California system contributed the most publications and the journal with the most publications was Circulation. JW Newburger was an authoritative author in this field. "Coronary artery lesion", "Intravenous immunoglobulin" (IVIG) and "Risk factor" were three prominent keywords. Keyword bursts changed from "TNF" and "IVIG", which focused on aetiology and treatment, to "Long term management", which emphasized the recovery period, and to "Kawasaki-like disease" and "Multisystem inflammatory syndrome" during the novel coronavirus pandemic. Trends of highly cited references indicated that landmark articles in different periods focused on Kawasaki disease guidelines, gene polymorphisms and multisystem inflammatory syndrome caused by the novel coronavirus. Conclusion: The aetiology of Kawasaki disease remains unclear, but viral infection is likely to play an important role. The combination of evolving sequencing technologies, large-scale epidemiological investigations and prospective cohort studies is likely to be important in exploring Kawasaki disease and improving its prognosis in future.
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Thermoelectric materials are highly promising for waste heat harvesting. Although thermoelectric materials research has expanded over the years, bismuth telluride-based alloys are still the best for near-room-temperature applications. In this work, a ≈38% enhancement of the average ZT (300-473 K) to 1.21 is achieved by mixing Bi0.4Sb1.6Te3 with an emerging thermoelectric material Sb2Si2Te6, which is significantly higher than that of most BiySb2-yTe3-based composites. This enhancement is facilitated by the unique interface region between the Bi0.4Sb1.6Te3 matrix and Sb2Si2Te6-based precipitates with an orderly atomic arrangement, which promotes the transport of charge carriers with minimal scattering, overcoming a common factor that is limiting ZT enhancement in such composites. At the same time, high-density dislocations in the same region can effectively scatter the phonons, decoupling the electron-phonon transport. This results in a ≈56% enhancement of the thermoelectric quality factor at 373 K, from 0.41 for the pristine sample to 0.64 for the composite sample. A single-leg device is fabricated with a high efficiency of 5.4% at ΔT = 164 K further demonstrating the efficacy of the Sb2Si2Te6 compositing strategy and the importance of the precipitate-matrix interface microstructure in improving the performance of materials for relatively low-temperature applications.
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Traditionally, the meniscus bottom is taken as the fluid front when tracking the fluid motion in capillary, but in simulation studies, the thus-calculated motion curve deviates notably from the modified Lucas-Washburn equation. Here, we report that, by considering a volume equivalent of the meniscus part, the motion of the equivalent front agrees very well with the theoretical prediction; furthermore, such an effective fluid front can be directly represented by a specific position of the meniscus, which is independent of the capillary radius. These findings provide an accurate and practical method for describing the motion of the fluid front in capillary.