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1.
Thorac Cancer ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39140206

RESUMEN

BACKGROUND: Lymph node (LN) metastasis is a significant prognostic factor for esophageal squamous cell carcinoma (ESCC), and there are no satisfactory methods for accurately predicting metastatic LNs. The present study aimed to assess the efficacy of 99mTc-3PRGD2 single-photon emission computed tomography (SPECT)/computed tomography (CT) for diagnosing metastatic LNs in ESCC. METHODS: A total of 15 enrolled patients with ESCC underwent 99mTc-3PRGD2 SPECT/CT and 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT) examinations preoperatively. High-definition bone carving reconstruction technology (HD-xSPECT Bone) was applied to quantitatively assess the LN's SUVmax via SPECT/CT. The two methods were compared for diagnosing metastatic LNs with pathology as the gold standard. RESULTS: Among 15 patients, 23 metastatic lymph node stations (mLNSs) were predicted by SPECT/CT, with a mean SUVmax of 2.71 ± 1.34, of which 15 were pathologically confirmed; 32 mLNSs were predicted by PET/CT with a mean SUVmax of 4.41 ± 4.02, of which 17 were pathologically confirmed. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of SPECT/CT for diagnosing metastatic LNs were 62.50%, 91.30%, 85.34%, 65.22%, and 90.32%, respectively, and those of PET/CT were 70.83%, 83.70%, 81.03%, 53.13%, and 91.67%, respectively. There was no significant difference in sensitivity (p = 0.061) or specificity (p = 0.058) between the two methods. The AUCSPECT/CT was 0.816 and the SUVmax threshold was 2.5. CONCLUSION: 99mTc-3PRGD2 SPECT/CT might be an effective method for diagnosing metastatic LNs in ESCC, especially in combination with HD-xSPECT Bone. The diagnostic efficiency of this method was noninferior to that of 18F-FDG PET/CT. The SUVmax threshold of 2.5 showed the highest agreement with the pathology findings.

2.
J Colloid Interface Sci ; 677(Pt B): 284-292, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39146816

RESUMEN

The shuttle effect of aluminum polysulfides (AlPSs) have been a source of concern for studying Al/S batteries. Due to the weak adsorption of CS composites, research on cathode materials for Al/S batteries has been delayed. As it is generally known that Al2S3 decomposition demands a large Gibbs free energy, this work has tried to reduce the Al2S3 decomposition potential energy. Herein, the Ni/Co bimetallic selenide reduces the energy barrier conversion and mitigates the polarization effects, while morphology control enables the storage and anchoring of S, alleviating the shuttle effect. Additionally, the intermediate products serve as single-atom catalysts, increasing the active sites, synergistically enhancing the ion diffusion kinetics. DFT calculations verify that NiCo2Se4 has a moderate Gibbs free energy change during the rate-limiting step of S reduction and the most robust adsorption energy to Al2S3. NiCo2Se4@CS2/Al has a remaining capacity of 135 mAh/g after 450 cycles (at 200 mA g-1), pioneering novel ideas for the development of Al/S batteries.

3.
Front Cell Dev Biol ; 12: 1375354, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39100091

RESUMEN

Background: In some patients, persistent gastrointestinal symptoms like abdominal pain, nausea, and diarrhea occur as part of long COVID-19 syndrome following acute respiratory symptoms caused by SARS-CoV-2. However, the characteristics of immune cells in the gastrointestinal tract of COVID-19 patients and their association with these symptoms remain unclear. Methodology: Data were collected from 95 COVID-19 patients. Among this cohort, 11 patients who exhibited gastrointestinal symptoms and underwent gastroscopy were selected. Using imaging mass cytometry, the gastrointestinal tissues of these patients were thoroughly analyzed to identify immune cell subgroups and investigate their spatial distribution. Results: Significant acute inflammatory responses were found in the gastrointestinal tissues, particularly in the duodenum, of COVID-19 patients. These alterations included an increase in the levels of CD68+ macrophages and CD3+CD4+ T-cells, which was more pronounced in tissues with nucleocapsid protein (NP). The amount of CD68+ macrophages positively correlates with the number of CD3+CD4+ T-cells (R = 0.783, p < 0.001), additionally, spatial neighborhood analysis uncovered decreased interactions between CD68+ macrophages and multiple immune cells were noted in NP-positive tissues. Furthermore, weighted gene coexpression network analysis was employed to extract gene signatures related to clinical features and immune responses from the RNA-seq data derived from gastrointestinal tissues from COVID-19 patients, and we validated that the MEgreen module shown positive correlation with clinical parameter (i.e., Total bilirubin, ALT, AST) and macrophages (R = 0.84, p = 0.001), but negatively correlated with CD4+ T cells (R = -0.62, p = 0.004). By contrast, the MEblue module was inversely associated with macrophages and positively related with CD4+ T cells. Gene function enrichment analyses revealed that the MEgreen module is closely associated with biological processes such as immune response activation, signal transduction, and chemotaxis regulation, indicating its role in the gastrointestinal inflammatory response. Conclusion: The findings of this study highlight the role of specific immune cell groups in the gastrointestinal inflammatory response in COVID-19 patients. Gene coexpression network analysis further emphasized the importance of the gene modules in gastrointestinal immune responses, providing potential molecular targets for the treatment of COVID-19-related gastrointestinal symptoms.

4.
J Colloid Interface Sci ; 677(Pt A): 1045-1051, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39134079

RESUMEN

Aqueous aluminium ion batteries (AAIBs) have attracted much attention due to their high theoretical capacity, safety, and environmental friendliness. However, the Research and Development (R&D) of cathode materials has limited its development and application. MoO3 has been proven to be a reliable and stable cathode material, nevertheless, it faces the dilemma of poor cycling performance and low specific capacity in AAIBs due to the irreversible phase transition in its structure. In this paper, MoO3 synthesized by a hydrothermal method has a unique nanobelt structure, which significantly enhances the structural stability of MoO3 and reduces its structural damage during charging/discharging. In addition, the nanobelt structure also gives MoO3 a rougher surface, which provides a large number of active sites and spaces for the insertion and extraction of Al3+ and improves the diffusion rate of Al3+ to a large extent. Experimental results demonstrate that this MoO3 nanobelt cathode exhibits significantly improved cycling stability and high specific capacity in AAIBs. This paper provides a practical solution to the existing challenges of AAIBs and further promotes the development and application of molybdenum-based materials in AAIBs.

5.
Nano Lett ; 24(28): 8542-8549, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38973706

RESUMEN

Aqueous aluminum-ion batteries (AAIBs) are considered a strong candidate for the new generation of energy storage devices. The lack of suitable cathode materials has been a bottleneck factor hindering the future development of AAIBs. In this work, we design and construct a highly effective cathode with dual morphologies. Two-dimensional (2D) layered MXene materials possessed good conductivity and hydrophilicity, which are used as the substrates to deposit rod-shaped vanadium oxides (V2O5) to form a three-dimensional (3D) cathode. The cathode design provides a strong boost for the rapid electrochemical activities of rod-shaped V2O5 by embedding/extracting both protons (H+) and aluminum-ion (Al3+). As a result, the V2O5@MXene cathode based AAIB delivers an ultrahigh initial specific capacity of 626 mAh/g at 0.1 A/g with a stable cycle performance up to 100 cycles. This work is a breakthrough for the development of cathode materials for AAIBs.

6.
Small ; : e2400335, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38682593

RESUMEN

Aluminum batteries (ABs) are identified as one of the most promising candidates for the next generation of large-scale energy storage elements because of their efficient three-electron reaction. Compared to ionic electrolytes, aqueous aluminum-ion batteries (AAIBs) are considered safer, less costly, and more environmentally friendly. However, considerable cycling performance is a key issue limiting the development of AAIBs. Stable, efficient, and electrolyte-friendly cathodes are most desirable for AAIBs. Herein, a rod-shaped defect-rich α-MnO2 is designed as a cathode, which is capable to deliver high performance with stable cycling for 180 cycles at 500 mA g-1 and maintains a discharge specific capacity of ≈100 mAh g-1. In addition, the infiltrability simulation is effectively utilized to corroborate the rapid electrochemical reaction brought about by the defective mechanism. With the formation of oxygen vacancies, the dual embedding of protons and metal ions is activated. This work provides a brand-new design for the development and characterization of cathodes for AAIBs.

7.
J Colloid Interface Sci ; 665: 181-187, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38522158

RESUMEN

Carbonyl or imine-based compounds have received a great deal of attention due to their high specific capacity and designability as cathodes for aqueous rechargeable organo-aluminum batteries. However, the inherent low conductivity and high solubility of carbonyl and imine-based compounds severely affect the cycling stability of aluminum batteries. Therefore, it is urgent to find an organic cathodes material with low solubility and good cycling performance. In this work, dibenzo[a,c]dibenzo[5,6:7,8]quinoxalino[2,3-i]phenazine-10,21-dione (DDQP) were synthesized by simple dehydration condensation to form new imine covalent bonds, which led to the synthesis of imine-conjugated backbone structures with carbonyl, extended π-conjugation planes, and increased active sites, resulting in increased specific capacities. Its storage mechanism with Al(OTF)2+ has also been confirmed. This monovalent ion usually possesses a lower coulombic interaction, which leads to a reduced solubility of DDQP during redox processes and improves its cyclic stability. The specific capacity of DDQP is 252.22 mAh/g at a current density of 400 mA g-1. After cycling, the discharge specific capacity remains at 219 mAh/g. Surprisingly, the conductivity of the battery also is improved by this structure of multiple active sites. And it can be further confirmed by theoretical calculations that the synthesis of DDQP realigns the arrangement of the electron cloud, enhances the electron affinity, and reduces the energy gap. This study provides a new reference for improving the performance of aqueous organic aluminum batteries.

8.
ACS Appl Mater Interfaces ; 16(8): 10061-10069, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38372285

RESUMEN

A dual-salt electrolyte with 5 M Al(OTF)3 and 0.5 M LiOTF is proposed for aqueous aluminum batteries, which can effectively prevent the corrosion caused by the hydrogen evolution reaction. With the addition of LiOTF in the electrolyte, the solvation phenomenon has changed with the coordination mode of Al3+ conversion from an all octahedral structure to a mixed octahedral and tetrahedral structure. This change can reduce the hydrogen bond between water molecules, which will minimize the occurrence of hydrogen evolution reactions. Moreover, the new electrolyte improves the cycle life of the battery. With MnO as the cathode, 2.1 V high charging platform and 1.5 V high discharge platform can be obtained. The electrochemical stability window (ESW) has been improved to 3.8 V. The first cycle capacity is up to 437 mAh g-1, which can be maintained at 103 mAh g-1 after 100 cycles. This work provides solutions for the future development of electrolyte for aqueous aluminum batteries.

10.
Biol Reprod ; 110(4): 648-659, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38224305

RESUMEN

Histone post-translational modifications, such as phosphorylation, methylation, acetylation, and ubiquitination, play vital roles in various chromatin-based cellular processes. Meiosis is crucial for organisms that depend on sexual reproduction to produce haploid gametes, during which chromatin undergoes intricate conformational changes. An increasing body of evidence is clarifying the essential roles of histone post-translational modifications during meiotic divisions. In this review, we concentrate on the post-translational modifications of H2A, H2B, H3, and H4, as well as the linker histone H1, that are required for meiosis, and summarize recent progress in understanding how these modifications influence diverse meiotic events. Finally, challenges and exciting open questions for future research in this field are discussed. Summary Sentence  Diverse histone post-translational modifications exert important effects on the meiotic cell cycle and these "histone codes" in meiosis might lead to the development of novel therapeutic strategies against reproductive diseases.


Asunto(s)
Cromatina , Histonas , Histonas/metabolismo , Procesamiento Proteico-Postraduccional , Fosforilación , Meiosis , Acetilación
11.
Nano Lett ; 23(24): 11842-11849, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38071640

RESUMEN

Aluminum-ion batteries have garnered an extensive amount of attention due to their superior electrochemical performance, low cost, and high safety. To address the limitation of battery performance, exploring new cathode materials and understanding the reaction mechanism for these batteries are of great significance. Among numerous candidates, multiple structures and valence states make manganese-based oxides the best choice for aqueous aluminum-ion batteries (AAIBs). In this work, a new cathode consists of γ-MnO2 with abundant oxygen vacancies. As a result, the electrode shows a high discharge capacity of 481.9 mAh g-1 at 0.2 A g-1 and a sustained reversible capacity of 128.6 mAh g-1 after 200 cycles at 0.4 A g-1. In particular, through density functional theory calculation and experimental comparison, the role of oxygen vacancies in accelerating the reaction kinetics of H+ has been verified. This study provides insights into the application of manganese dioxide materials in aqueous AAIBs.

12.
Org Biomol Chem ; 21(47): 9422-9427, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37987684

RESUMEN

Enol ethers are essential synthetic frameworks and widely applied in organic synthesis; however, high regio- and stereo-selective access to enol ethers remains challenging. Herein, we report a titanium-catalyzed stereospecific anti-Markovnikov hydroalkoxylation reaction of alkynes for the synthesis of Z-enol ethers with excellent functional group tolerance and yields. Mechanistic studies showed that the titanium coordinates with the alkyne and then an oxygen anion attacks the π-bond of the alkyne from the backside to provide a trans-oxygen metallation intermediate, which accounts for the high Z-stereoselectivity. Furthermore, Z-enol ethers could be applied as a kind of synthon for late-stage transformations and gram-scale synthesis, which demonstrates their potential value in organic synthesis.

13.
J Colloid Interface Sci ; 652(Pt B): 1438-1446, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37659312

RESUMEN

With its consistent thermal runaway temperature and superior capacity, aluminum ion batteries have emerged as a key area for battery development. At the moment, electrode material is the main focus of aluminum ion battery capacity enhancement. Selenide is anticipated to develop into a high-performance cathode for aluminum ion batteries, since it is a type of high energy density electrode material. However, because selenide is soluble in acid electrolytes, Al-Se batteries have low cycle performance and cannot keep up with the present demand for electronic gadgets. Here, homogeneous-structured precursors were created via a hydrothermal reaction, and MnSe2-MnSe heterojunction hollow spheres were created a step further via temperature control of the selenidation reaction. With 103.76 mAh/g of specific capacity remaining after 3000 cycles at 1.0 A/g, this novel heterojunction material exhibits astounding cycle stability. After additional investigation, it was shown that the MnSe2-MnSe heterojunction may prevent the dispersion of the active substances, significantly enhancing the cycle performance. The density of states (DOS) of electrode materials demonstrates the superior electronic conductivity of this heterojunction material. Meanwhile, it was computationally demonstrated that the MnSe2-MnSe heterojunction has a strong adsorption energy for AlCl4-, thus accelerating the reaction kinetics. In summary, the performance of selenides has been improved by this novel heterojunction material, which also makes for a superior cathode material.

14.
Am J Med Sci ; 366(6): 430-437, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37660993

RESUMEN

BACKGROUND: Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can infect the gastrointestinal (GI) tract in coronavirus disease 2019 (COVID-19) patients, the mechanism of GI tract injury is largely unknown. We aimed to study the potential factors that cause COVID-19 GI symptoms. METHODS: We investigated the expression and co-localization of angiotensin converting enzyme 2 (ACE2), transmembrane serine protease 2 (TMPRSS2), SARS-CoV-2 nucleocapsid protein (NP), and the severity of inflammation in GI tissues from COVID-19 patients (n = 19) by immunofluorescence and histopathologic staining, and then studied their associations with GI symptoms. RESULTS: Infected stomach tissues showed significantly higher ACE2 expression than uninfected ones, while infected duodenum tissues showed significantly higher TMPRSS2 expression than uninfected ones. The expression of TMPRSS2 exhibited a moderate correlation with viral NP across different GI tissues, while no significant association was observed between ACE2 and viral NP. Some GI symptoms such as diarrhea and nausea, were related to the expression level of ACE2, TMPRSS2 or the severity of inflammation. Furthermore, age and elevated aspartate transaminase were major risk factors for disease progression. CONCLUSIONS: ACE2 and TMPRSS2 were essential proteins in the SARS-CoV-2 infection of GI tract, while TMPRSS2 rather than ACE2 may play a more important role. GI symptoms may derive from the host receptor expression level and pro-inflammatory response in COVID-19 patients after viral infection of GI tissues, and further exacerbate the disease. So targeting TMPRSS2 and inflammation may represent an effective strategy for treating COVID-19 patients with GI symptoms.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Enzima Convertidora de Angiotensina 2 , Tracto Gastrointestinal , Inflamación , Proteínas de la Nucleocápside , Serina Endopeptidasas
15.
Colloids Surf B Biointerfaces ; 230: 113523, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37634286

RESUMEN

Polyetheretherketone (PEEK) is being increasingly recognized as a highly promising polymer implant in orthopaedics due to its advantageous biocompatibility, favorable processability, and radiation resistance. Nonetheless, the long-term application of PEEK implants in vivo faces challenges due to unfavorable post-implantation inflammatory and immune reactions, which result in suboptimal osseointegration rates. Hence, biofunctionalizing the surface of PEEK implants emerges as a viable strategy to enhance osseointegration and increase the success rate. In this study, we developed a multifunctional PEEK implant through the in-situ incorporation of chitosan-coated bioactive glass nanoparticles (BGNs). This approach can impart immunomodulatory properties and enhance the potential for osseointegration. The resulting biofunctionalized PEEK material exhibited multiple beneficial effects. For instance, it facilitated M2 phenotypic polarization of macrophages, diminished the expression of inflammatory factors, and enhanced the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro. Moreover, it exhibited an improved capacity for osseointegration when tested in vivo. The findings of the experiment highlighted the pivotal and complex role of the biofunctionalized PEEK implant in maintaining typical bone immunity and metabolism. The study proposes that the application of chitosan-BGNs presents a straightforward approach to developing multifunctional implants with the ability to promote biomineralization and immunomodulation, specifically tailored for orthopaedic applications.


Asunto(s)
Quitosano , Magnesio , Osteogénesis , Regeneración Ósea , Polietilenglicoles/farmacología , Diferenciación Celular
16.
J Colloid Interface Sci ; 651: 296-303, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37542904

RESUMEN

Due to their high reactivity and theoretical capacity, chalcogen elements have been favored and applied in many battery studies. However, the high surface charge density and high solubility of these elements as electrode materials have hindered their deeper exploration due to the shuttle effect. In this article, organic structural triphenylphosphine is used as a molecular main chain structure, and chalcogen elements O, S, and Se are introduced to combine with P as active sites. This approach not only takes advantage of the beneficial effects of the aromatic ring on the physical and chemical properties of the chalcogen element but also allows for the optimization of its advantages. By utilizing Triphenylphosphine selenide (TP-Se) as the cathode material in aluminum-ion batteries(AIBs), a high-performance Al-organic battery was fabricated, which exhibited a high initial capacity of 180.6 mAh g-1 and stable cycling for up to 1000 cycles. Based on density functional theory (DFT) calculations, TP-Se exhibits a smaller energy gap, which renders it favorable for chemical reactions. Moreover, the calculated results suggest that TP-Se tends to undergo redox reactions with AlCl2+. The molecular structure of triphenylphosphine and its combination with Se offers an enticing pathway for designing cathode materials in aluminum-organic batteries.

17.
Small Methods ; 7(10): e2300663, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37462249

RESUMEN

Aluminum ion batteries (AIBs) are widely regarded as the most potential large-scale metal ion battery because of its high safety and environment-friendly characteristics. To solve the problem of weak electrical conductivity of organic materials, different structures of cyano organic molecules with electrophilic properties are selected as the cathode materials of aluminum batteries. Through experimental characterization and density functional theory theoretical calculation, Phthalonitrile is the best cathode material among the five organic molecules and proved that the C≡N group is the active site for insertion/extraction of AlCl2 + ions. The first cycle-specific capacity of the assembled flexible package battery is as high as 191.92 mAh g-1 , the discharge-specific capacity is 112.67 mAh g-1 after 1000 cycles, and the coulombic efficiency is ≈97%. At the same time, the influences of different molecular structures and functional groups on the battery are also proved. These research results lay a foundation for selecting safe and stable organic aluminum batteries and provide a new reference for developing high-performance AIBs.

18.
J Exp Clin Cancer Res ; 42(1): 136, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37254126

RESUMEN

BACKGROUND: Increasing evidence indicates that the tumor microenvironment (TME) is a crucial determinant of cancer progression. However, the clinical and pathobiological significance of stromal signatures in the TME, as a complex dynamic entity, is still unclear in esophageal squamous cell carcinoma (ESCC). METHODS: Herein, we used single-cell transcriptome sequencing data, imaging mass cytometry (IMC) and multiplex immunofluorescence staining to characterize the stromal signatures in ESCC and evaluate their prognostic values in this aggressive disease. An automated quantitative pathology imaging system determined the locations of the lamina propria, stroma, and invasive front. Subsequently, IMC spatial analyses further uncovered spatial interaction and distribution. Additionally, bioinformatics analysis was performed to explore the TME remodeling mechanism in ESCC. To define a new molecular prognostic model, we calculated the risk score of each patient based on their TME signatures and pTNM stages. RESULTS: We demonstrate that the presence of fibroblasts at the tumor invasive front was associated with the invasive depth and poor prognosis. Furthermore, the amount of α-smooth muscle actin (α-SMA)+ fibroblasts at the tumor invasive front positively correlated with the number of macrophages (MØs), but negatively correlated with that of tumor-infiltrating granzyme B+ immune cells, and CD4+ and CD8+ T cells. Spatial analyses uncovered a significant spatial interaction between α-SMA+ fibroblasts and CD163+ MØs in the TME, which resulted in spatially exclusive interactions to anti-tumor immune cells. We further validated the laminin and collagen signaling network contributions to TME remodeling. Moreover, compared with pTNM staging, a molecular prognostic model, based on expression of α-SMA+ fibroblasts at the invasive front, and CD163+ MØs, showed higher accuracy in predicting survival or recurrence in ESCC patients. Regression analysis confirmed this model is an independent predictor for survival, which also identifies a high-risk group of ESCC patients that can benefit from adjuvant therapy. CONCLUSIONS: Our newly defined biomarker signature may serve as a complement for current clinical risk stratification approaches and provide potential therapeutic targets for reversing the fibroblast-mediated immunosuppressive microenvironment.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas/patología , Linfocitos T CD8-positivos/metabolismo , Pronóstico , Fibroblastos/metabolismo , Microambiente Tumoral
19.
Int J Biol Macromol ; 239: 124263, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37004929

RESUMEN

In this work, we prepared polyhydroxylated lignin by demethylation and hydroxylation of lignin, and grafted phosphorus-containing groups by nucleophilic substitution reaction, the resulting material could be used as a carrier for the preparation of heterogeneous Cu-based catalysts (PHL-CuI-OPR2). The optimal PHL-CuI-OPtBu2 catalyst was characterized by FT-IR, TGA, BET, XRD, SEM-EDS, ICP-OES, XPS. The catalytic performance of PHL-CuI-OPtBu2 in the Ullmann CN coupling reaction was evaluated using iodobenzene and nitroindole as model substrates under nitrogen atmosphere with DME and H2O as cosolvent at 95 °C for 24 h. The applicability of modified lignin-supported copper catalyst was investigated of various aryl/heteroaryl halides with indoles under optimal conditions, the corresponding products were obtained with high yield. Additionally, it could be easily recovered from the reaction medium by an easy centrifugation and washing.


Asunto(s)
Cobre , Lignina , Cobre/química , Espectroscopía Infrarroja por Transformada de Fourier , Catálisis
20.
ACS Appl Mater Interfaces ; 14(43): 48780-48788, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36265080

RESUMEN

The fabrication of cathode materials with ideal kinetic behavior is important to improve the electrochemical performance of aluminum-ion batteries (AIBs). Transition metal selenides have the advantages of abundant reserves and high discharge specific capacity and discharge voltage plateau, which makes them a promising material for rechargeable AIBs. It is well-known that the low structural stability and relatively poor reaction kinetics pose a considerable challenge to the development of AIBs. The cubic structure of Cu2Se-Cu1.8Se can adapt to the volume change of the active material during cycling and facilitate the intercalation and deintercalation of chloroaluminate anions in the cathode material. We created a two-fold protection mechanism for AIBs with a CMK-3 modified separator and a Cu2Se-Cu1.8Se heterojunction coated with MXene in order to better mitigate the detrimental impacts. In addition to offering numerous electronic transmission routes, MXene and CMK-3 help prevent the solubilization of active species. This novel design enables the Cu2Se-Cu1.8Se@MXene composite to have a high initial discharge capacity of 705.5 mAh g-1 at 1.0 A g-1. Even after 1500 cycles at 2.0 A g-1, the capacity is still maintained at 225.1 mAh g-1. Furthermore, the reaction mechanism of AlCl4- intercalated/deintercalated into Cu2Se-Cu1.8Se heterojunction is revealed during charge/discharge. This work to construct novel cathode materials has greatly improved the electrochemical performance of AIBs.

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