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1.
Angew Chem Int Ed Engl ; : e202412735, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39205491

RESUMO

The rapid transport kinetics of divalent magnesium ions are crucial for achieving distinguished performance in aqueous magnesium-ion battery-based energy storage capacitors. However, the strong electrostatic interaction between Mg2+ with double charges and the host material significantly restricts Mg2+ diffusivity. In this study, a new composite material, EDA-Mn2O3, with double-energy storage mechanisms comprising an organic phase (ethylenediamine, EDA) and an inorganic phase (manganese sesquioxide) was successfully synthesized via an organic-inorganic coupling strategy. Inorganic-phase Mn2O3 serves as a scaffold structure, enabling the stable and reversible intercalation/deintercalation of magnesium ions. The organic phase EDA adsorbed onto the surface of Mn2O3 as an elastic matrix, works synergistically with Mn2O3, and utilizes bidentate chelating ligands to capture Mg2+. The robust coordination effect of terminal biprotonic amine in EDA enhances the structural diversity and specific capacity characteristics of the composite material, as further corroborated by density functional theory (DFT) calculations, ex-situ XRD, XPS, and Raman spectroscopy. As expected, an aqueous magnesium ion capacitor with EDA-Mn2O3 serving as the cathode can reach 110.17 Wh/kg. This study aimed to explore the practical application value of organic‒inorganic composite electrodes with double-energy storage mechanisms.

2.
Small ; 19(45): e2304913, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37434105

RESUMO

Zn dendrite formation is the main obstacle to commercializing aqueous zinc-ion batteries (ZIBs). α-cyclodextrin (α-CD) is proposed as an environmentally friendly macromolecule additive in the ZnSO4 -based electrolyte to obtain stable and reversible Zn anodes. The results show that α-CD molecules' unique 3D structure can effectively regulate the mass transfer of the electrolyte components and isolate the Zn anode from H2 O molecules. The α-CD provides abundant electrons to the Zn (002) crystallographic plane, which induces charge density redistribution. Such an effect relieves the reduction and aggregation of Zn2+ cations while protecting the Zn metal anode from water molecules. Finally, a small amount of α-CD additive (0.01 M) can enhance the performance of Zn significantly in Zn||Cu cells (1980 cycles with 99.45% average CE) and Zn||Zn cells (8000 h ultra-long cycle life). The excellent practical applicability was further verified in Zn||MnO2 cells.

3.
J Org Chem ; 88(24): 17227-17236, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38019169

RESUMO

This study presents a convenient approach to the synthesis of indole- and benzofuran-based benzylic sulfones using unactivated alkynes containing aryl iodides and sodium sulfinates under visible light irradiation. The procedure involves a sequential series of dehalogenation, carbo-cyclization, and radical sulfonylation. Plausible insights into the reaction mechanism are derived from control experiments, leading to the proposal of a radical cascade reaction pathway.

4.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(7): 817-820, 2022 Jul 15.
Artigo em Zh | MEDLINE | ID: mdl-35894199

RESUMO

A boy, aged 2 years and 5 months, had recurrent epistaxis, and the coagulation function examination showed that activated partial thromboplastin time (APTT) was significantly prolonged. Further laboratory examinations showed that the prolonged APTT was not immediately corrected in the APTT correction test, with positive lupus anticoagulant and low prothrombin activity. The boy was diagnosed with hypoprothrombinemia-lupus anticoagulant syndrome. The condition was improved after treatment with glucocorticoid, immunoglobulin, and vitamin K1. The boy has been followed up for 6 months, and no epistaxis was observed. Prothrombin activity returned to normal, and lupus anticoagulant remained positive. This is a relatively rare disease, and for patients with bleeding symptoms and coagulation disorders, it is recommended to perform the tests such as APTT correction test, lupus anticoagulant testing, and coagulation factor dilution test, which can improve the detection rate of this disease, so as to achieve early diagnosis, provide rational treatment in the early stage, and improve the prognosis.


Assuntos
Síndrome Antifosfolipídica , Transtornos da Coagulação Sanguínea , Hipoprotrombinemias , Síndrome Antifosfolipídica/diagnóstico , Pré-Escolar , Epistaxe/etiologia , Humanos , Hipoprotrombinemias/diagnóstico , Inibidor de Coagulação do Lúpus , Masculino , Tempo de Tromboplastina Parcial , Protrombina
5.
Chem Commun (Camb) ; 60(65): 8597-8600, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39045830

RESUMO

V3O7·H2O (VO) stands out as a highly promising cathode material for aqueous zinc-ion batteries (AZIB). However, due to the instability of the VO structure and the limited ion transport rate, achieving the required specific capacity and extended cycling lifespan has been challenging. To tackle this issue, we synthesized Mg-ion intercalated VO (MgVO) using a straightforward hydrothermal method. Introducing Mg2+ as an interlayer support enhanced the flexibility of MgVO within the confined layer space, stabilized its lamellar structure, and expanded the VO layer spacing. The AZIB employing the MgVO cathode demonstrated a high specific capacity of 382.7 mA h g-1 at a current density of 0.1 A g-1 and showed excellent cycling stability. The robust structural stability of MgVO suggests promising applications for large-scale energy storage, while the Mg2+ intercalation strategy presents a novel approach for exploring other potential cathode materials.

6.
Nanoscale ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39189424

RESUMO

Ni3(NO3)2(OH)4 has a high theoretical specific capacitance, low cost, and environmental friendliness, making it a promising electrode material. Specifically, Ni3(NO3)2(OH)4 electrodes have a larger layer spacing (c = 6.898 Å) than Ni(OH)2 electrodes since NO3- has a much larger ionic radius than OH-. The larger layer spacing stores more electrolyte ions, significantly improving the electrochemical activity of the electrodes. Additionally, the interlayer NO3- can enhance the structural stability of Ni3(NO3)2(OH)4. However, since Ni3(NO3)2(OH)4 has a higher molar mass than Ni(OH)2, it has a lower theoretical specific capacity. Consequently, Ni3(NO3)2(OH)4 has not been used in zinc-based alkaline batteries. Studies showed that doping could enhance the electrochemical performance of electrode materials. Therefore, this study used a simple solvothermal reaction to synthesize yttrium-doped Ni3(NO3)2(OH)4 (Y-Ni3(NO3)2(OH)4), assembling a Y-Ni3(NO3)2(OH)4//Zn battery for electrochemical testing. Y-Ni3(NO3)2(OH)4 served as the cathode in the battery. The analysis of Y-Ni3(NO3)2(OH)4 showed that yttrium (Y) doping increased the specific surface area and pore size of Ni3(NO3)2(OH)4 significantly. The increased specific surface area improved the active material utilization, and the abundant mesopores facilitated OH- transport, substantially enhancing the battery's specific capacity and energy density. Ultimately, the specific discharge capacity of the advanced Y-Ni3(NO3)2(OH)4//Zn battery reached 177.97 mA h g-1 at a current density of 4 A g-1, nearly doubling the capacity of the earlier Ni3(NO3)2(OH)4//Zn battery (103.59 mA h g-1).

7.
RSC Adv ; 14(1): 700-706, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38173585

RESUMO

Selectively producing a variety of valuable compounds using controlled chemical reactions starting from a common material is an appealing yet complex concept. Herein, a photocatalytic approach for the selective synthesis of (E)-ß-aminovinyl sulfones and (E)-ß-amidovinyl sulfones from allenamides and sodium sulfinates was established. This reaction exhibits the traits of an eco-friendly solvent and adjustable amide cleavage, and can accommodate a diverse range of substrates with exceptional functional group tolerance. Based on control experiments and deuterium labeling experiments, a plausible radical reaction pathway is proposed.

8.
Chem Commun (Camb) ; 59(29): 4316-4319, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36946238

RESUMO

Herein, Fe-doped Co3O4 (Fe-Co3O4) was prepared to solve the issues of poor electrical conductivity and the lack of active sites in Co3O4 materials. Due to having similar radius and physical/chemical properties to Co, Fe is an ideal choice for doping Co3O4, as it can improve intrinsic conductivity without causing severe lattice distortion. Oxygen vacancies are gradually formed as doping reactions occur to maintain electric neutrality. Owing to the merits of oxygen vacancies in Co3O4, the distribution of the electrons is changed, thus optimizing the material's intrinsic charge/ion states and modifying the band gap by introducing impurity levels. Moreover, the surface area of Fe-Co3O4 is 1.5 times larger than that of the original material. The synergistic effect promotes the electrochemical oxidation reduction reaction and improves the capacitance and cycling stability. Finally, such an advanced Zn//Fe-Co3O4 battery exhibits a discharge-specific capacity of 171.97 mA h g-1, nearly eight times higher than that of the previous Zn//Co3O4 battery (22.38 mA h g-1). In addition, the attenuation of the capacity was almost negligible after 9000 cycles.

9.
Chem Commun (Camb) ; 58(16): 2686-2689, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35107457

RESUMO

An aqueous room-temperature phosphorescent (RTP) probe for Gd3+ is reported based on Gd3+-induced intersystem promoting effect and the oxygen-shielding property of the Gd3+/AMP/fluorescein coordination polymer nanoparticles (CPNs). Besides selective Gd3+ detection, the results are important for harnessing the advantages of RTP detection in an aerated aqueous solution, which is difficult with current phosphors.

10.
ACS Appl Mater Interfaces ; 14(13): 15059-15068, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35343225

RESUMO

Biofilms, an accumulation of microorganisms, cause persistent bacterial infection and low cure rate due to the remarkable drug resistance. Photodynamic inactivation (PDI) is a promising treatment modality for bacterial infections, but the formation of biofilms raises new challenges for photosensitizers (PSs), particularly the reactive oxygen species (ROS) generation efficiency. Herein, through targeting the Jablonski energy diagram, we proposed a universal "three-in-one" matrix of Gd3+-ADP assembly for encapsulation and fixing of PSs to inhibit non-radiative transitions and promoting intersystem crossing (ISC) by the heavy atom and paramagnetic effects of Gd3+, eventually resulted in boosted ROS generation from the existing PSs (1.5-9.0-fold). Particularly, photophysical studies indicated that the matrix resulted in simultaneous ISC promotion and triplet-state lifetime lengthening, which is essential for ROS boosting. The PDI performance of the matrix was confirmed through fast and effective elimination of bacterial biofilms in 10-30 min. Moreover, successful therapy of a Pseudomonas aeruginosa biofilm-infected all-thickness third-degree burn wound was achieved within 11 days with Ce 6@CNs (matrix) but not feasible for matrix-free PSs (Ce 6 only), which highlighted the role of "three-in-one" matrix in ROS boosting.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Biofilmes , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio/farmacologia , Estados Unidos , United States Food and Drug Administration
11.
Chem Commun (Camb) ; 58(33): 5112-5115, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35377376

RESUMO

A new and expedient photocatalytic protocol for the construction of quinolin-2(1H)-ones via Markovnikov-type sulfonylation/6-endo-trig cyclization/selective C(O)-CF3 bond cleavage starting from N-alkyl-N-(2-ethynylphenyl)-2,2,2-trifluoroacetamides and sulfinic acids has been developed. It is as an unprecedented protocol for the preparation of 4-sulfonylquinoline-2(1H)-ones with high efficiency, mild reaction conditions, acceptable yields and a wide range of substrates.


Assuntos
Alcinos , Quinolinas , Alcinos/química , Ciclização , Estrutura Molecular
12.
RSC Adv ; 12(14): 8443-8448, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35424818

RESUMO

An atom-economic method of preparing allylic sulfones via hydrosulfonylation of allenes with sulfinic acids under Pd(0)-catalysis was reported. This process has a high degree of regio- and stereoselectivity, and provides the target product with a moderate to excellent yield. A wide range of nitrogen- or oxygen-containing linear E-allylic sulfones have been synthesized. With the support of experimental research, a possible mechanism was proposed.

13.
Nat Commun ; 12(1): 526, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483514

RESUMO

Aciduric bacteria that can survive in extremely acidic conditions (pH < 4.0) are challenging to the current antimicrobial approaches, including antibiotics and photodynamic bacteria inactivation (PDI). Here, we communicate a photosensitizer design concept of halogenation of fluorescein for extremely acidic PDI. Upon halogenation, the well-known spirocyclization that controls the absorption of fluorescein shifts to the acidic pH range. Meanwhile, the heavy atom effect of halogens boosts the generation of singlet oxygen. Accordingly, several photosensitizers that could work at even pH < 2.0 were discovered for a broad band of aciduric bacteria families, with half maximal inhibitory concentrations (IC50) lower than 1.1 µM. Since one of the discovered photosensitizers is an FDA-approved food additive (2',4',5',7'-tetraiodofluorescein, TIF), successful bacteria growth inhibition in acidic beverages was demonstrated, with greatly extended shelf life from 2 days to ~15 days. Besides, the in vivo PDI of Candidiasis with TIF under extremely acidic condition was also demonstrated.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Fluoresceína/farmacologia , Luz , Fármacos Fotossensibilizantes/farmacologia , Ácidos/química , Animais , Bactérias/classificação , Bactérias/efeitos da radiação , Feminino , Fluoresceína/química , Halogenação , Humanos , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos ICR , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Estrutura Molecular , Oxigênio Singlete/química , Oxigênio Singlete/metabolismo
14.
Chem Commun (Camb) ; 56(56): 7749-7752, 2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32662779

RESUMO

A catalytic 1,6-nucleophilic addition/annulation cascade was developed for the first time, and used to produce 27 hitherto unreported ethylene-linked 1-naphthol-imidazole pairs with generally good yields and complete stereoselectivity. An Ag2O-catalyzed reaction of yne-allenone esters with tosylmethyl isocyanide proceeded efficiently, and provided a simple and convergent protocol for the synthesis of fully substituted (Z)-ethylenes whereas tetrasubstituted (E)-ethylenes were obtained when ethyl isocyanoacetate was employed in this transformation. The reaction pathway consists of [2+2] cycloaddition, 1,6-nucleophilic addition and [3+2] cycloaddition, leading to continuous multiple bond-forming events including C-C and C-N bonds to construct complex molecules.

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