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1.
Adv Sci (Weinh) ; : e2409084, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373360

RESUMO

Electrochemical extraction has the potential to enhance uranium (U) extraction capacity and rates, but thus far, high selectivity and energy efficiency have not been achieved through the design of electrode materials. Herein, a precise electrocatalysis strategy is developed using a Ferrum (Fe) porphyrin-phenanthroline conjugated network (Fe@PDACN) for energy-efficient uranium extraction. The phenanthroline provides specific binding sites for selective enrichment of U(VI) at active sites (Kd = 2.79 × 105 mL g-1 in multi-ion solution). The Fe(II) sites have strong trap-redox activity for U(VI) and act as dynamic electron donors to rapidly mediate electrocatalytic U(VI) extraction through the redox reaction of Fe(0/II)/Fe(III). Moreover, the Fe-porphyrin blocks support sustained electron donation for U(VI) electrocatalysis by pre-storing electrons. These features enable selective uranium capture and a high electroextraction capacity of 24 646.3 mg g-1 from simulated nuclear wastewater in 280 h at a low voltage of -1.5 V. An ultra-high Faraday efficiency of 90.1% is achieved, and the energy cost is 3.22 × 10-2 $ kg-1 U, significantly lower than the previously reported materials. This work provides a highly efficient strategy for uranium extraction from water.

2.
Chem Commun (Camb) ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39397533

RESUMO

We present a Cu/PTFE electrode for the CO2 reduction reaction with a high coverage of *OH which facilitates both the activation of CO2 and the C-C coupling, leading to a faradaic efficiency for ethylene exceeding 50% at an exceptionally low potential of -246 mV vs. RHE, with the maximum FEC2H4 reaching 60.3%.

3.
Small ; : e2404060, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235565

RESUMO

In recent years, catalysts based on transition metal sulfides have garnered extensive attention due to their low cost and excellent electrocatalytic activity in the alkaline oxygen evolution reaction. Here, the preparation of Fe-doped Ni3S2 via a one-step hydrothermal approach is reported by utilizing inexpensive transition metals Ni and Fe. In an alkaline medium, Fe-Ni3S2 exhibits outstanding electrocatalytic activity and stability for the OER, and the current density can reach 10 mA cm-2 with an overpotential of 163 mV. In addition, Pt/C||Fe-Ni3S2 is used as the membrane electrode of the anion exchange membrane water electrolyzer, which is capable of providing a current density of 650 mA cm-2 at a cell voltage of 2.0 V, outperforming the benchmark Ir/C. The principle is revealed that the doping of Fe enhances the electrocatalytic water decomposition ability of Ni3S2 by in situ Raman and in situ X-ray absorption fine structure. The results indicate that the doping of Fe decreases the charge density near Ni atoms, which renders Fe-Ni3S2 more favorable for the adsorption of OH- and the formation of *OO- intermediates. This work puts forward an effective strategy to significantly improve both the alkaline OER activity and stability of low-cost electrocatalysts.

4.
Adv Sci (Weinh) ; : e2401236, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090836

RESUMO

Anionic redox allows the direct formation of O─O bonds from lattice oxygens and provides higher catalytic in the oxygen evolution reaction (OER) than does the conventional metal ion mechanism. While previous theories have predicted and experiments have suggested the possible O─O bond, it has not yet been directly observed in the OER process. In this study, operando soft X-ray absorption spectroscopy (sXAS) at the O K-edge and the operando Raman spectra is performed on layered double CoFe hydroxides (LDHs) after intercalation with [Cr(C2O4)3]3-, and revealed a three-step oxidation process, staring from Co2+ to Co3+, further to Co4+ (3d6L), and ultimately leading to the formation of O─O bonds and O2 evolution above a threshold voltage (1.4 V). In contrast, a gradual oxidation of Fe is observed in CoFe LDHs. The OER activity exhibits a significant enhancement, with the overpotential decreasing from 300 to 248 mV at 10 mA cm-2, following the intercalation of [Cr(C2O4)3]3- into CoFe LDHs, underscoring a crucial role of anionic redox in facilitating water splitting.

5.
Inorg Chem ; 63(28): 12764-12773, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38950312

RESUMO

Cobalt (Co)-based materials have been widely investigated as hopeful noble-metal-free alternatives for the oxygen evolution reaction (OER) in alkaline electrolytes, which is crucial for generating hydrogen by water electrolysis. Herein, cobalt-based telluride particles with good electronic conductivity as anodic electrocatalysts were prepared under vacuum by the solid-state strategy, which display remarkable activities toward the OER. Nickel (Ni) and iron (Fe) codoped cobalt telluride (NiFe-CoTe) exhibits an overpotential of 321 mV to achieve a current density of 10 mA cm-2 and a Tafel slope of 51.8 mV dec-1, outperforming the performances of CoTe, CoTe2, and IrO2. According to the DFT calculation, the adsorbed hydroxyl-assisted adsorbate evolution mechanism was proposed for the OER process of NiFe-CoTe, which reveals the synergetic effect toward OER induced by codoping of the Ni and Fe atoms. This work proposes a rational strategy to prepare cobalt-based tellurides as efficient OER catalysts in alkaline electrolytes, providing a new strategy to prepare and regulate metal-based tellurides for catalysis and beyond.

6.
Medicine (Baltimore) ; 103(29): e38780, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39029018

RESUMO

To comprehensively analyze the psychological health status of operating room nurses and identify influencing factors. The research compares psychological health differences based on nurses' years of experience, specifically examining depression and anxiety scores. A detailed assessment was conducted, focusing on nurses with varying experience levels. Findings revealed higher depression scores among mid to senior-level nurses, while junior-level nurses exhibited elevated anxiety scores. Additionally, overall dissatisfaction with physical health and various subhealth symptoms were reported. Multifactorial analysis identified working hours, disaster relief experience, and perceived occupational benefits as primary influencers. Through comparative analysis, it was found that the average score of self-rating depression scale and self-rating anxiety scale was 53.8 ±â€…12.2 points and 47.6 ±â€…10.5 points respectively. The depression score of middle and senior nurses was significantly higher than that of junior nurses (P < .05). The anxiety score of primary nurses was significantly higher than that of middle and senior nurses (P < .05). The results indicate that the duration of work, previous experience in disaster relief, and nurses' perception of occupational benefits were the main factors influencing the psychological health status of operating room nurses (P < .05). Healthcare institutions are recommended to implement targeted interventions based on nurses' experience levels, addressing specific psychological health needs. Future research should delve into specific subgroups, conduct long-term tracking, expand the scope of influencing factors, assess the effectiveness of intervention measures, and explore cross-cultural aspects.


Assuntos
Ansiedade , Depressão , Humanos , Adulto , Feminino , Ansiedade/psicologia , Masculino , Depressão/psicologia , Depressão/epidemiologia , Saúde Mental , Enfermagem de Centro Cirúrgico , Recursos Humanos de Enfermagem Hospitalar/psicologia , Salas Cirúrgicas , Nível de Saúde , Satisfação no Emprego , Inquéritos e Questionários , Pessoa de Meia-Idade
7.
Angew Chem Int Ed Engl ; 63(39): e202409763, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-38954763

RESUMO

Developing non-platinum group metal catalysts for the sluggish hydrogen oxidation reaction (HOR) is critical for alkaline fuel cells. To date, Ni-based materials are the most promising candidates but still suffer from insufficient performance. Herein, we report an unconventional hcp/fcc Ni (u-hcp/fcc Ni) heteronanocrystal with multiple epitaxial hcp/fcc heterointerfaces and coherent twin boundaries, generating rugged surfaces with plenty of asymmetric convex sites. Systematic analyses discover that such convex sites enable the adsorption of *H in unusual bridge positions with weakened binding energy, circumventing the over-strong *H adsorption on traditional hollow positions, and simultaneously stabilizing interfacial *H2O. It thus synergistically optimizes the HOR thermodynamic process as well as reduces the kinetic barrier of the rate-determining Volmer step. Consequently, the developed u-hcp/fcc Ni exhibits the top-rank alkaline HOR activity with a mass activity of 40.6 mA mgNi -1 (6.3 times higher than fcc Ni control) together with superior stability and high CO-tolerance. These results provide a paradigm for designing high-performance catalysts by shifting the adsorption state of intermediates through configuring surface sites.

8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(3): 762-768, 2024 May 20.
Artigo em Chinês | MEDLINE | ID: mdl-38948302

RESUMO

Objective: Ultrasound diagnosis and treatment is easy to perform and takes little time. It is widely used in clinical practice thanks to its non-invasive, real-time, and dynamic characteristics. In the process of ultrasound diagnosis and treatment, the probe may come into contact with the skin, the mucous membranes, and even the sterile parts of the body. However, it is difficult to achieve effective real-time disinfection of the probes after use and the probes are often reused, leading to the possibility of the probes carrying multiple pathogenic bacteria. At present, the processing methods for probes at home and abroad mainly include probe cleaning, probe disinfection, and physical isolation (using probe covers or sheaths). Yet, each approach has its limitations and cannot completely prevent probe contamination and infections caused by ultrasound diagnosis and treatment. For example, when condoms are used as the probe sheath, the rate of condom breakage is relatively high. The cutting and fixing of cling film or freezer bags involves complicated procedures and is difficult to perform. Disposable plastic gloves are prone to falling off and causing contamination and are hence not in compliance with the principles of sterility. Furthermore, the imaging effect of disposable plastic gloves is poor. Therefore, there is an urgent need to explore new materials to make probe covers that can not only wrap tightly around the ultrasound probe, but also help achieve effective protection and rapid reuse. Based on the concept of physical barriers, we developed in this study a heat sealing system for the rapid reuse of ultrasound probes. The system uses a heat sealing device to shrink the protective film so that it wraps tightly against the surface of the ultrasound probe, allowing for the rapid reuse of the probe while reducing the risk of nosocomial infections. The purpose of this study is to design a heat sealing system for the rapid reuse of ultrasound probes and to verify its application effect on the rapid reuse of ultrasound probes. Methods: 1) The heat sealing system for the rapid reuse of ultrasound probes was designed and tested by integrating medical and engineering methods. The system included a protective film (a multilayer co-extruded polyolefin thermal shrinkable film) and a heat sealing device, which included heating wire components, a blower, a photoelectric switch, temperature sensors, a control and drive circuit board, etc. According to the principle of thermal shrinkage, the ultrasound probe equipped with thermal shrinkable film was rapidly heated and the film would wrap closely around the ultrasound probe placed on the top of the heat sealing machine. The ultrasound probe was ready for use after the thermal shrinkage process finished. Temperature sensors were installed on the surface of the probe to test the thermal insulation performance of the system. The operation procedures of the system are as follows: placing the ultrasound probe covered with the protective film in a certain space above the protective air vent, which is detected by the photoelectric switch; the heating device heats the thermal shrinkable film with a constant flow of hot air at a set temperature value. Then, the probe is rotated so that the thermal shrinkable film will quickly wrap around the ultrasound probe. After the heat shrinking is completed, the probe can be used directly. 2) Using the convenience sampling method, 90 patients from the Department of Anesthesiology and Perioperative Medicine, the First Affiliated Hospital of Xi'an Jiaotong University were included as the research subjects. All patients were going to undergo arterial puncture under ultrasound guidance. The subjects were divided into 3 groups, with 30 patients in each group. Three measures commonly applied in clinical practice were used to process the probes in the three groups and water-soluble fluorescent labeling was applied around the puncture site before use. In the experimental group, the probes were processed with the heat sealing system. The standard operating procedures of the heat sealing system for rapid reuse of ultrasonic probes were performed to cover the ultrasonic probe and form a physical barrier to prevent probe contamination. There were two control groups. In control group 1, disinfection wipes containing double-chain quaternary ammonium salt were used to repeatedly wipe the surface of the probe for 10-15 times, and then the probe was ready for use once it dried up. In the control group 2, a disposable protective sheath was used to cover the front end of the probe and the handle end of the sheath was tied up with threads. Comparison of the water-soluble fluorescent labeling on the surface of the probe (which reflected the colony residues on the surface of the probe) before and after use and the reuse time (i.e., the lapse of time from the end of the first use to the beginning of the second use) were made between the experimental group and the two control groups. Results: 1) The temperature inside the ultrasound probe was below 40 ℃ and the heat sealing system for rapid reuse did not affect the performance of the ultrasound probe. 2) The reuse time in the heat sealing system group, as represented by (median [P25, P75]), was (8.00 [7.00, 10.00]) s, which was significantly lower than those of the disinfection wipe group at (95.50 [8.00, 214.00]) s and the protective sleeve group at (25.00 [8.00, 51.00]) s, with the differences being statistically significant (P<0.05). No fluorescence residue was found on the probe in either the heat sealing system group or the protective sheath group after use. The fluorescence residue in the heat sealing system group was significantly lower than that in the disinfection wipes group, showing statistically significant differences (χ 2=45.882, P<0.05). Conclusion: The thermal shrinkable film designed and developed in this study can be cut and trimmed according to the size of the equipment. When the film is heated, it shrinks and wraps tightly around the equipment, forming a sturdy protective layer. With the heat sealing system for rapid reuse of ultrasonic probes, we have realized the semi-automatic connection between the thermal shrinkable film and the heating device, reducing the amount of time-consuming and complicated manual operation. Furthermore, the average reuse time is shortened and the system is easy to use, which contributes to improvements in the reuse and operation efficiency of ultrasound probes. The heat sealing system reduces colony residues on the surface of the probe and forms an effective physical barrier on the probe. No probes were damaged in the study. The heat sealing system for rapid reuse of ultrasonic probes can be used as a new method to process the ultrasonic probes.


Assuntos
Ultrassonografia , Ultrassonografia/instrumentação , Ultrassonografia/métodos , Temperatura Alta , Reutilização de Equipamento , Humanos , Desinfecção/métodos , Desinfecção/instrumentação , Desenho de Equipamento , Contaminação de Equipamentos/prevenção & controle
9.
ACS Nano ; 18(22): 14496-14506, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38771969

RESUMO

Hydrogen obtained from electrochemical water splitting is the most promising clean energy carrier, which is hindered by the sluggish kinetics of the oxygen evolution reaction (OER). Thus, the development of an efficient OER electrocatalyst using nonprecious 3d transition elements is desirable. Multielement synergistic effect and lattice oxygen oxidation are two well-known mechanisms to enhance the OER activity of catalysts. The latter is generally related to the high valence state of 3d transition elements leading to structural destabilization under the OER condition. We have found that Al doping in nanosheet Ni-Fe hydroxide exhibits 2-fold advantage: (1) a strong enhanced OER activity from 277 mV to 238 mV at 10 mA cm-2 as the Ni valence state increases from Ni3.58+ to Ni3.79+ observed from in situ X-ray absorption spectra. (2) Operational stability is strengthened, while weakness is expected since the increased NiIV content with 3d8L2 (L denotes O 2p hole) would lead to structural instability. This contradiction is attributed to a reduced lattice oxygen contribution to the OER upon Al doping, as verified through in situ Raman spectroscopy, while the enhanced OER activity is interpreted as an enormous gain in exchange energy of FeIV-NiIV, facilitated by their intersite hopping. This study reveals a mechanism of Fe-Ni synergy effect to enhance OER activity and simultaneously to strengthen operational stability by suppressing the contribution of lattice oxygen.

10.
Front Neurol ; 15: 1376216, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606277

RESUMO

Objectives: This study aimed to investigate the efficacy of using a newly formulated magnesium-rich artificial cerebrospinal fluid (MACSF) as an alternative to normal saline (NS) for intraoperative irrigation during aneurysm clipping in improving the prognosis of patients with Aneurysmal subarachnoid hemorrhage (aSAH). Methods: Patients with aSAH who underwent intraoperative irrigation with MACSF or NS during the clipping in the First Affiliated Hospital of Xi 'an Jiaotong University from March 2019 to March 2022 were selected as MACSF group and NS group, respectively. The primary prognostic indicators were the incidence of favorable outcomes (mRS 0-2). The secondary outcome measures included cerebral vasospasm (CVS), mortality, total hospital stay, and intensive care unit (ICU) stay. Safety was evaluated based on the occurrence rates of hypermagnesemia, meningitis, and hydrocephalus. Results: Overall, 34 and 37 patients were enrolled in the MACSF and NS groups, respectively. At 90 days after aSAH onset, the proportion of favorable prognosis in the MACSF group was significantly higher than that in the NS group (p = 0.035). The incidence of CVS within 14 days after surgery was significantly lower in the MACSF group than that in the NS group (p = 0.026). The mortality rate in the MACSF group was significantly lower than in the NS group (p = 0.048). The median lengths of hospital stay (p = 0.008) and ICU stay (p = 0.018) were significantly shorter in the MACSF group than in the NS group. No significant differences were observed in safety measures. Conclusion: Using MACSF as an irrigation fluid for aneurysm clipping can significantly improve the 90-day prognosis of patients with aSAH, which may be related to the reduced incidence of CVS. Clinical trial registration: https://www.clinicaltrials.gov, identifier NCT04358445.

11.
Small Methods ; 8(8): e2400178, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38686689

RESUMO

Reversible solid oxide cells (rSOCs) have significant potential as efficient energy conversion and storage systems. Nevertheless, the practical application of their conventional air electrodes, such as La0.8Sr0.2MnO3-δ (LSM), Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF), and PrBa0.8Ca0.2Co2O5+δ (PBCC), remains unsatisfactory due to interface delamination during prolonged electrochemical operation. Using micro-focusing X-ray absorption spectroscopy (µ-XAS), a decrease (increase) in the co-valence state from the electrode surface to the electrode/electrolyte interface is observed, leading to the above delamination. Utilizing the one-pot method to incorporate an oxygen-vacancy-enriched CeO2 electrode into these air electrodes, the uniform distribution of the Co valence state is observed, alleviating the structural delamination. PBCC-CeO2 electrodes exhibited a degradation rate of 0.095 mV h-1 at 650 °C during a nearly 500-h test as compared with 0.907 mV h-1 observed during the 135-h test for PBCC. Additionally, a remarkable increase in electrolysis current density from 636 to 934 mA cm-2 under 1.3 V and a maximum power density from 912 to 989 mW cm-2 upon incorporating CeO2 into PBCC is also observed. BSCF-CeO2 and LSM-CeO2 also show enhanced electrochemical performance and prolonged stability as compared to BSCF and LSM. This work offers a strategy to mitigate the structural delamination of conventional electrodes to boost the performance of rSOCs.

12.
Small ; 20(34): e2400042, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38600889

RESUMO

Modulating the coordination environment of the metal active center is an effective method to boost the catalytic performances of metal-organic frameworks (MOFs) for oxygen evolution reaction (OER). However, little attention has been paid to the halogen effects on the ligands engineering. Herein, a series of MOFs X─FeNi-MOFs (X = Br, Cl, and F) is constructed with different coordination microenvironments to optimize OER activity. Theoretical calculations reveal that with the increase in electronegativity of halogen ions in terephthalic acid molecular (TPA), the Bader charge of Ni atoms gets larger and the Ni-3d band center and O-2p bands move closer to the Fermi level. This indicates that an increase in ligand negativity of halogen ions in TPA can promote the adsorption ability of catalytic sites to oxygen-containing intermediates and reduce the activation barrier for OER. Experimental also demonstrates that F─FeNi-MOFs exhibit the highest catalytic activity with an ultralow overpotential of 218 mV at 10 mA cm-2, outperforming most otate-of-the-art Fe/Co/Ni-based MOFs catalysts, and the enhanced mass activity by seven times compared with that for the sample before ligands engineering. This work opens a new avenue for the realization of the modulation of NiFe─O bonding by halogen ion in TPA and improves the OER performance of MOFs.

13.
Dalton Trans ; 53(16): 7067-7072, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38566555

RESUMO

The electrochemical reduction of CO2 to CO is a powerful approach to achieving carbon neutrality. Herein, we report a five-nuclear copper cluster-based metal-azolate framework CuTz-1 as an electrocatalyst for the electrochemical CO2 reduction reaction. It achieved a faradaic efficiency (FE) of 62.7% for yielding CO with a partial current density of -35.1 mA cm-2 in flow cell device, which can be preserved for more than ten hours with negligible changes of the current density and FE(CO). Studies of electrocatalytic mechanism studies revealed that the distance of Cu-N was increased, and the coordination number of the Cu ion was reduced, while the oxidation state of Cu was decreased after the electrocatalysis. These findings offer valuable insights into structural changes that influence the performance of the catalyst during the process of the electrochemical reduction of CO2 process.

14.
Nat Commun ; 15(1): 2777, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555416

RESUMO

Garnet-type Li6.5La3Zr1.5Ta0.5O12 (LLZO) is considered a promising solid electrolyte, but the surface degradation in air hinders its application for all-solid-state battery. Recent studies have mainly focused on the final products of the LLZO surface reactions due to lacking of powerful in situ characterization methods. Here, we use ambient pressure X-ray spectroscopies to in situ investigate the dynamical evolution of LLZO surface in different gas environments. The newly developed ambient pressure mapping of resonant Auger spectroscopy clearly distinguishes the lithium containing species, including LiOH, Li2O, Li2CO3 and lattice oxygen. The reaction of CO2 with LLZO to form Li2CO3 is found to be a thermodynamically favored self-limiting reaction. On the contrary, the reaction of H2O with LLZO lags behind that of CO2, but intensifies at high pressure. More interestingly, the results provide direct spectroscopic evidence for the existence of Li+/H+ exchange and reveal the importance of the initial layer formed on clean electrolyte surface in determining their air stability. This work demonstrates that the newly developed in situ technologies pave a new way to investigate the oxygen evolution and surface degradation mechanism in energy materials.

15.
Heliyon ; 10(2): e24530, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38312582

RESUMO

1.2 Previous studies have confirmed that air and light pollution can cause damage to a number of systems throughout the body, including the ocular surface and retina. However, the exact effect of air pollution and light pollution on tear film function is not clear. This study explored the different operation room environmental exposures on tear film function before and after operation. Sixty medical staff in the operating room were selected and divided into 4 groups according to different surgical methods to evaluate the tear film function before and after operation: Da Vinci surgery group (DVSS), Laparoscopic surgery group (LS), Traditional surgery group (TS), and Ophthalmic microsurgery group (OM). The results showed that the levels of light and air pollution were elevated in operating rooms during the operation and the changes of tear film function in the other three groups were statistically significant except for DVSS group. In TS group, particulate matter (pm) 1 (R = 0.61, p < 0.01), pm2.5 (R = 0.63, p < 0.01), and pm10 (R = 0.67, p < 0.01) were positively correlated with eye redness index, and first and average noninvasive tear film break-up times were positively correlated with illuminance (R = 0.54, p < 0.05; R = 0.97, p < 0.01). In OM group, there was a positive correlation between the operation time and the first (R = 0.69, p < 0.01) and average (R = 0.89, p < 0.01) noninvasive tear film break-up times. Our research found that exposure to different operating room environment will lead to damage of tear film function, but also provide a theoretical basis for the improvement of surgical environment.

16.
Nat Commun ; 14(1): 7984, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38042884

RESUMO

Protonic ceramic fuel cells with high efficiency and low emissions exhibit high potential as next-generation sustainable energy systems. However, the practical proton conductivity of protonic ceramic electrolytes is still not satisfied due to poor membrane sintering. Here, we show that the dynamic displacement of Y3+ adversely affects the high-temperature membrane sintering of the benchmark protonic electrolyte BaZr0.1Ce0.7Y0.1Yb0.1O3-δ, reducing its conductivity and stability. By introducing a molten salt approach, pre-doping of Y3+ into A-site is realized at reduced synthesis temperature, thus suppressing its further displacement during high-temperature sintering, consequently enhancing the membrane densification and improving the conductivity and stability. The anode-supported single cell exhibits a power density of 663 mW cm-2 at 600 °C and long-term stability for over 2000 h with negligible performance degradation. This study sheds light on protonic membrane sintering while offering an alternative strategy for protonic ceramic fuel cells development.

17.
Adv Sci (Weinh) ; 10(33): e2303693, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37863664

RESUMO

MXene-supported noble metal alloy catalysts exhibit remarkable electrocatalytic activity in various applications. However, there is no facile one-step method for synthesizing these catalysts, because the synthesis of MXenes requires a strongly oxidizing environment and the preparation of platinum nanoalloys requires a strongly reducing environment and high temperatures. Hence, achieving coupling in one step is extremely challenging. In this paper, a straightforward one-step molten salt method for preparing MXene-supported platinum nanoalloy catalysts is proposed. The molten salt acts as the reaction medium to dissolve the transition metals and platinum ions at high temperatures. Transition metal ions oxidize the A-site element from its MAX precursor at high temperatures, and the resulting transition metals further reduce platinum ions to form alloys. By coupling Al oxidation and platinum ion reduction using a molten salt solvent, this method directly converts Ti3 AlC2 to a Pt-M@Ti3 C2 Tx catalyst (where M denotes the transition metal). It further offers the possibility of extending the Pt-M phase to binary, ternary, or quaternary platinum-containing nanoalloys and converting the Al-containing MAX phase to Ti2 AlC and Ti3 AlCN. Due to the strong interfacial interaction, the as-prepared Pt-Co@Ti3 C2 Tx is superior to commercial Pt/C (20 wt.%) in the hydrogen evolution reaction.

18.
Chem Commun (Camb) ; 59(33): 4958-4961, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37014679

RESUMO

Post-synthetic linker installation in a single-crystal-to-single-crystal manner was crystallographically demonstrated in thorium-based metal-organic frameworks (Th-MOFs), not only leading to the discovery of an extremely rare framework de-interpenetration, but also representing an unprecedented strategy for boosting iodine adsorption capacity.

19.
Nat Commun ; 14(1): 2112, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055401

RESUMO

Designing efficient catalyst for the oxygen evolution reaction (OER) is of importance for energy conversion devices. The anionic redox allows formation of O-O bonds and offers higher OER activity than the conventional metal sites. Here, we successfully prepare LiNiO2 with a dominant 3d8L configuration (L is a hole at O 2p) under high oxygen pressure, and achieve a double ligand holes 3d8L2 under OER since one electron removal occurs at O 2p orbitals for NiIII oxides. LiNiO2 exhibits super-efficient OER activity among LiMO2, RMO3 (M = transition metal, R = rare earth) and other unary 3d catalysts. Multiple in situ/operando spectroscopies reveal NiIII→NiIV transition together with Li-removal during OER. Our theory indicates that NiIV (3d8L2) leads to direct O-O coupling between lattice oxygen and *O intermediates accelerating the OER activity. These findings highlight a new way to design the lattice oxygen redox with enough ligand holes created in OER process.

20.
Psychiatry Res ; 323: 115172, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36958092

RESUMO

Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent psychiatric disorders that affects children and even continues into adulthood. Dexmedetomidine (DEX), a short-term sedative, can selectively activate the α2-adrenoceptor. Treatment with α2-adrenergic agonists in patients with ADHD is becoming increasingly common. However, the therapeutic potential of DEX for the treatment of ADHD is unknown. Here, we evaluated the effect of DEX on ADHD-like behavior in spontaneously hypertensive rats (SHRs), a widely used animal model of ADHD. DEX treatment ameliorated hyperactivity and spatial working memory deficits and normalized θ electroencephalogram (EEG) rhythms in SHRs. We also found that DEX treatment altered the gut microbiota composition and promoted the enrichment of beneficial gut bacterial genera associated with anti-inflammatory effects in SHRs. The gut pathological scores and permeability and the level of inflammation observed in the gut and brain were remarkably improved after DEX administration. Moreover, transplantation of fecal microbiota from DEX-treated SHRs produced effects that mimicked the therapeutic effects of DEX administration. Therefore, DEX is a promising treatment for ADHD that functions by reshaping the composition of the gut microbiota and reducing inflammation in the gut and brain.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Dexmedetomidina , Encefalite , Microbioma Gastrointestinal , Ratos , Animais , Dexmedetomidina/farmacologia , Dexmedetomidina/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Ratos Endogâmicos SHR , Inflamação/tratamento farmacológico
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