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1.
Nanomicro Lett ; 16(1): 194, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743294

RESUMO

Aqueous zinc-ion batteries (AZIBs) are one of the most compelling alternatives of lithium-ion batteries due to their inherent safety and economics viability. In response to the growing demand for green and sustainable energy storage solutions, organic electrodes with the scalability from inexpensive starting materials and potential for biodegradation after use have become a prominent choice for AZIBs. Despite gratifying progresses of organic molecules with electrochemical performance in AZIBs, the research is still in infancy and hampered by certain issues due to the underlying complex electrochemistry. Strategies for designing organic electrode materials for AZIBs with high specific capacity and long cycling life are discussed in detail in this review. Specifically, we put emphasis on the unique electrochemistry of different redox-active structures to provide in-depth understanding of their working mechanisms. In addition, we highlight the importance of molecular size/dimension regarding their profound impact on electrochemical performances. Finally, challenges and perspectives are discussed from the developing point of view for future AZIBs. We hope to provide a valuable evaluation on organic electrode materials for AZIBs in our context and give inspiration for the rational design of high-performance AZIBs.

2.
Adv Sci (Weinh) ; 11(23): e2310239, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582519

RESUMO

Rationally designed organic redox-active materials have attracted numerous interests due to their excellent electrochemical performance and reasonable sustainability. However, they often suffer from poor cycling stability, intrinsic low operating potential, and poor rate performance. Herein, a novel Donor-Acceptor (D-A) bipolar polymer with n-type pyrene-4,5,9,10-tetraone unit storing Li cations and p-type carbazole unit which attracts anions and provides polymerization sites is employed as a cathode for lithium-ion batteries through in situ electropolymerization. The multiple redox reactions and boosted kinetics by the D-A structure lead to excellent electrochemical performance of a high discharge capacity of 202 mA h g-1 at 200 mA g-1, impressive working potential (2.87 and 4.15 V), an outstanding rate capability of 119 mA h g-1 at 10 A g-1 and a noteworthy energy density up to 554 Wh kg-1. This strategy has significant implications for the molecule design of bipolar organic cathode for high cycling stability and high energy density.

3.
Small ; 20(27): e2308748, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38282458

RESUMO

The upconversion luminescence (UCL) in the second near-infrared window (NIR-II) is highly attractive due to its excellent performance in high-resolution bioimaging, anticounterfeiting, and temperature sensing. However, upconvertion nanoparticles (UCNPs) are normally emitted in visible light, potentially impacting the imaging quality. Here, a monochromatic Er3+-rich (NaErF4:x%Yb@NaYF4) nanoparticles with excitation at 1532 nm and emission at 978 nm is proposed, both situated in the NIR-II region. The proper proportion of Yb3+ ions doping has a positive effect on the NIR-II emission, by enhancing the cross relaxation efficiency and accelerating the energy transfer rate. Owing to the interaction between the Er3+ and Yb3+ is inhibited at low temperatures, the UCL emission intensities at visible and NIR-II regions show opposite trend with temperature changing, which establishes a fitting formula to derive temperature from the luminous intensity ratio, promoting the potential application of UCL in NIR-II regions for the temperature sensing.

4.
ChemSusChem ; 17(4): e202301809, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38230562

RESUMO

Dual-ion batteries based on organic electrodes show great potential to break through the bottlenecks existed in conventional LIBs due to their high specific capacity, lifted working voltage, and environmental benignity. Herein, two innovative viologen-based bipolar copolymers poly(viologen-pyrene-4,5,9,10-tetrone dichloride) (PVPTOCl2 ) and poly(viologen-anthraquinone dichloride) (PVAQCl2 ) were synthesized and applied as high performance cathodes for lithium-dual-ion battery. Bearing the dual-ion storage capability of viologen and carbonyls, as well as the conjugated structure of pyrene-4,5,9,10-tetrone, the synthesized copolymers show remarkable electrochemical performances for LIBs. Compared to PVAQCl2 , PVPTOCl2 shows superior electrochemical performance with high initial specific capacity (235.0 mAh g-1 at 200 mA g-1 ), high reversibility (coulombic efficiency up to 99.96 % at 1 A g-1 ), excellent rate performance (150.3 mAh g-1 at 5 A g-1 ) and outstanding cycling stability (a reversible capacity of 197.5 mAh g-1 at a current density of 1 A g-1 and a low capacity loss per cycle of 0.11‰ during 3000 cycles). Moreover, the charge storage mechanism was systematically investigated by ex-situ FT-IR, ex-situ XPS and DFT calculations. The results clearly reveal the structure-property relationship of the bipolar-molecules, providing a new platform to develop efficient bipolar materials for dual-ion batteries.

5.
Materials (Basel) ; 16(16)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37629933

RESUMO

Organic lanthanide complexes have garnered significant attention in various fields due to their intriguing energy transfer mechanism, enabling the upconversion (UC) of two or more low-energy photons into high-energy photons. In comparison to lanthanide-doped inorganic nanoparticles, organic UC complexes hold great promise for biological delivery applications due to their advantageous properties of controllable size and composition. This review aims to provide a summary of the fundamental concept and recent developments of organic lanthanide-based UC materials based on different mechanisms. Furthermore, we also detail recent applications in the fields of bioimaging and solar cells. The developments and forthcoming challenges in organic lanthanide-based UC offer readers valuable insights and opportunities to engage in further research endeavors.

6.
Chem Sci ; 13(25): 7475-7481, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35872819

RESUMO

Alkynes are widely used in chemistry, medicine and materials science. Here we demonstrate a transition-metal and photocatalyst-free inverse Sonogashira coupling reaction between iodoalkynes and (hetero)arenes or alkenes under visible-light irradiation. Mechanistic and computational studies suggest that iodoalkynes can be directly activated by visible light irradiation, and an excited state iodoalkyne acted as an "alkynyl radical synthetic equivalent", reacting with a series of C(sp2)-H bonds for coupling products. This work should open new windows in radical chemistry and alkynylation method.

7.
J Mater Chem C Mater ; 10(2): 688-695, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35127099

RESUMO

Collaborative therapy is regarded as an effective approach in increasing the therapeutic efficacy of cancer. In this work, we have proposed and validated the concept of upconversion lumienscence image guided synergy of photodynamic therapy (PDT) and radiotherapy (RT) for deep cancer, via a specially designed nanoplatform integrating near infrared (NIR) light activated luminescence upconversion and X-ray induced scintillation. Upon NIR light irradiation, the nanoplatform emits highly monochromatic red light solely for imaging the targeted cancer cells without triggering therapy; however, when the irradiation turns to a low dose of X-rays, scintillation will occur which induces effectively the PDT destroying the cancer cells together with X-ray induced RT. The novel theranostic nanoplatform is constructed in such a way that the interactions between the upconversion core and the outmost scintillating shell are blocked effectively by an inert layer between them. This structural design not only enables a nearly perfect excitation energy delivery (∼100% at a spectral overlapping wavelength of ∼540 nm) from the outermost scintellating layer to the surface-anchored photosensitizers and so a maximum yield of radical oxygen species, but also achieves a strong NIR induced upconversion luminescence for imaging. Since PDT and RT attack different parts of a cancer cell, this synergy is more effective in destroying cancer than a single therapy, resulting in the reduction of the X-ray irradiation dosage. As a proof of principle, the theranostic effect is validated by in vitro and in vivo experiments, exhibiting the great potential of this sort of nanoplatform in deep cancer treatment.

8.
Orthop J Sports Med ; 9(9): 23259671211026624, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34604425

RESUMO

BACKGROUND: Medial patellofemoral ligament (MPFL) reconstruction, MPFL repair, and nonoperative treatment are important treatments for patients with patellar dislocation. However, it is unclear which treatment leads to better outcomes. PURPOSE: To determine the efficacy and safety of the 3 treatments in the treatment of patellar dislocation and compare the effect of MPFL reconstruction with MPFL repair, MPFL reconstruction with nonoperative treatment, and MPFL repair with nonoperative treatment. STUDY DESIGN: Systematic review; Level of evidence, 3. METHODS: The PubMed, Web of Science, Cochrane Library, Embase, CNKI (China National Knowledge Infrastructure), and Wanfang databases were searched from inception to December 2020. Included were clinical studies that described the efficacy and safety of 2 of the 3 treatments, studies directly comparing the clinical effects of the 2 operative techniques, or studies comparing the effects of reconstruction or repair with nonoperative treatment. Two reviewers independently extracted data and assessed the quality of the included studies with the Cochrane risk-of-bias tools. The outcomes evaluated were postoperative redislocation rate, revision rate, complications, and Kujala score. We used traditional direct pairwise meta-analysis as well as network meta-analysis for comprehensive efficacy of all 3 treatment measures. RESULTS: Twelve studies were included: 5 compared MPFL reconstruction with MPFL repair, 2 compared MPFL reconstruction with nonoperative treatment, and 5 compared MPFL repair with nonoperative treatment. The risk of bias was serious in 4, moderate in 4 and low in 4 articles. MPFL reconstruction led to significantly reduced redislocation and improved Kujala scores compared with MPFL repair and nonoperative treatment. MPFL repair led to reduced redislocation rates compared with nonoperative treatment but did not show an obvious benefit in primary dislocations. There was no significant difference among the 3 treatments in terms of revision rate and incidence of complications, although we found that treatment-related complications were least likely to occur in nonoperative treatment. CONCLUSION: The results of this review indicate that MPFL reconstruction decreases recurrent dislocation compared with MPFL repair or nonoperative treatment, but it has a higher possibility of complications. MPFL repair resulted in less postoperative redislocation than nonoperative treatment but did not show an obvious benefit in primary dislocation.

10.
Angew Chem Int Ed Engl ; 59(40): 17580-17586, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32618035

RESUMO

A practicable strategy to rationally obtain the reversible mechanochromic luminescent (MCL) material with high-contrast ratio (green versus red) has been established. By introducing a volatile third party (small-sized solvent molecules) into the lattice of charge transfer (CT) cocrystal of mixed-stacking 1:1 coronene (Cor.) and napthalenetetracarboxylic diimide (NDI), a noteworthy reconfigurable molecular assembly is ingeniously achieved owing to the loosely packing arrangement as well as weakened intermolecular interactions. Accordingly, the CT excited state, strongly corresponding to the molecular stacking modes, can be intentionally tailored through external stimulus (heating, grinding, or solvent), accompanying distinct changes in photophysical properties. Subsequently, a high-contrast reversible MCL with highly sensitive and good reproducibility is realized and the underlying mechanism is thoroughly revealed.

11.
ChemSusChem ; 13(9): 2457-2463, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31782976

RESUMO

Searching new organic cathode materials to address the issues of poor cycle stability and low capacity in lithium ion batteries (LIBs) is very important and highly desirable. In this research, a 2D boroxine-linked chemically-active pyrene-4,5,9,10-tetraone (PTO) covalent organic framework (2D PPTODB COFs) was synthesized as an organic cathode material with remarkable electrochemical properties, including high electrochemical activity (four redox electrons), safe oxidation potential window (between 2.3 and 3.08 V vs. Li/Li+ ), superb structural/chemical stability, and strong adhesiveness. A binder-free cathode was obtained by mixing 70 wt % PPTODB and 30 wt % carbon nanotubes (CNTs) as a conductive additive. Promoted by the fast kinetics of electrons/ions, high electrochemical activity, and effective π-π interaction between PPTODB and CNTs, LIBs with the as-prepared cathode exhibited excellent electrochemical performance: a high specific capacity of 198 mAh g-1 , a superb rate ability (the capacity at 1000 mA g-1 can reach 76 % of the corresponding value at 100 mA g-1 ), and a stable coulombic efficiency (≈99.6 % at the 150th cycle). This work suggests that the concept of binder-free 2D electroactive materials could be a promising strategy to approach energy storage with high energy density.

12.
Polymers (Basel) ; 11(1)2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30960091

RESUMO

Organic thermoelectric (TE) materials can directly convert heat to electricity, and they are emerging as new materials for energy harvesting and cooling technologies. The performance of TE materials mainly depends on the properties of materials, including the Seebeck coefficient, electrical conductivity, thermal conductivity, and thermal stability. Traditional TE materials are mostly based on low-bandgap inorganic compounds, such as bismuth chalcogenide, lead telluride, and tin selenide, while organic materials as promising TE materials are attracting more and more attention because of their intrinsic advantages, including cost-effectiveness, easy processing, low density, low thermal conductivity, and high flexibility. However, to meet the requirements of practical applications, the performance of organic TE materials needs much improvement. A variety of efforts have been made to enhance the performance of organic TE materials, including the modification of molecular structure, and chemical or electrochemical doping. In this review, we summarize recent progress in organic TE materials, and discuss the feasible strategies for enhancing the properties of organic TE materials for future energy-harvesting applications.

13.
Chem Asian J ; 14(13): 2210-2214, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31016880

RESUMO

A novel conjugated copolymer has been synthesized and employed as an organic cathode material in rechargeable lithium-ion batteries (LIBs). Due to the synergistic effects from conducting aniline and pyrene units, the resultant batteries based on the as-obtained copolymer can deliver a promising reversible specific capacity of 113 mAh g-1 with a high voltage output of 3.2 V and a remarkable 75.2 % capacity retention after 180 cycles. Moreover, an excellent rate performance is also achieved with a fast recovery of the capacity at different current densities.

14.
Angew Chem Int Ed Engl ; 58(19): 6449-6454, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-30779454

RESUMO

Herein, two new quadrupolar acceptor-π-donor-π-acceptor (A-π-D-π-A) chromophores have been prepared featuring a strongly electron-donating diborene core and strongly electron-accepting dimesitylboryl (BMes2 ) and bis(2,4,6-tris(trifluoromethyl)phenyl)boryl (BF Mes2 ) end groups. Analysis of the compounds by NMR spectroscopy, X-ray crystallography, cyclic voltammetry, and UV/Vis-NIR absorption and emission spectroscopy indicated that the compounds have extended conjugated π-systems spanning their B4 C8 cores. The combination of exceptionally potent π-donor (diborene) and π-acceptor (diarylboryl) groups, both based on trigonal boron, leads to very small HOMO-LUMO gaps, resulting in strong absorption in the near-IR region with maxima in THF at 840 and 1092 nm and very high extinction coefficients of ca. 120 000 m-1  cm-1 . Both molecules also display weak near-IR fluorescence with small Stokes shifts.

15.
Nat Commun ; 10(1): 169, 2019 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-30635576

RESUMO

The features of well-conjugated and planar aromatic structures make π-conjugated luminescent materials suffer from aggregation caused quenching (ACQ) effect when used in solid or aggregated states, which greatly impedes their applications in optoelectronic devices and biological applications. Herein, we reduce the ACQ effect by demonstrating a facile and low cost method to co-assemble polycyclic aromatic hydrocarbon (PAH) chromophores and octafluoronaphthalene together. Significantly, the solid photoluminescence quantum yield (PLQYs) for the as-resulted four micro/nanococrystals are enhanced by 254%, 235%, 474 and 582%, respectively. Protection from hydrophilic polymer chains (P123 (PEO20-PPO70-PEO20)) endows the cocrystals with superb dispersibility in water. More importantly, profiting from the above-mentioned highly improved properties, nano-cocrystals present good biocompatibility and considerable cell imaging performance. This research provides a simple method to enhance the emission, biocompatibility and cellular permeability of common chromophores, which may open more avenues for the applications of originally non- or poor fluorescent PAHs.


Assuntos
Antracenos/química , Fluorocarbonos/química , Luminescência , Naftalenos/química , Compostos Policíclicos/química , Humanos , Células MCF-7 , Nanopartículas/análise , Nanopartículas/química , Imagem Óptica
16.
Biochem Biophys Res Commun ; 501(1): 55-63, 2018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29678580

RESUMO

Fracture healing is a repair process of a mechanical discontinuity loss of force transmission, and pathological mobility of bone. Increasing evidence suggests that microRNA (miRNA) could regulate chondrocyte, osteoblast, and osteoclast differentiation and function, indicating miRNA as key regulators of bone formation, resorption, remodeling, and repair. Hence, during this study, we established a right femur fracture mouse model to explore the effect microRNA-185 (miR-185) has on osteoblasts in mice during fracture healing and its underlying mechanism. After successfully model establishment, osteoblasts were extracted and treated with a series of mimics or inhibitors of miR-185, or siRNA against PTH. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot analysis were performed to determine the levels of miR-185, PTH, ß-catenin and Wnt5b. Cell viability, cycle distribution and apoptosis were detected by means of MTT and flow cytometry assays. Dual luciferase reporter gene assay verified that PTH is a target gene of miR-185. Osteoblasts transfected with miR-185 mimics or siRNA against PTH presented with decreased levels of PTH, ß-catenin and Wnt5b which indicated that miR-185 blocks the Wnt/ß -catenin axis by inhibiting PTH. Moreover, miR-185 inhibitors promoted the osteoblast viability and reduced apoptosis with more cells arrested at the G1 stage. MiR-185 mimics were observed to have inhibitory effects on osteoblasts as opposed to those induced by miR-185 inhibitors. Above key results indicated that suppression of miR-185 targeting PTH could promote osteoblast growth and proliferation in mice during fracture healing through activating Wnt/ß -catenin axis.


Assuntos
Consolidação da Fratura/genética , MicroRNAs/genética , Osteoblastos/citologia , Osteoblastos/metabolismo , Hormônio Paratireóideo/antagonistas & inibidores , Hormônio Paratireóideo/genética , Animais , Apoptose/genética , Ciclo Celular/genética , Proliferação de Células/genética , Células Cultivadas , Regulação para Baixo , Consolidação da Fratura/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/agonistas , MicroRNAs/antagonistas & inibidores , Modelos Animais , Hormônio Paratireóideo/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
17.
Zhongguo Gu Shang ; 29(5): 472-5, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-27505968

RESUMO

OBJECTIVE: To investigate results of total knee arthroplasty using the long-stem tibial component combined with metallic wedge of knee prosthesis for the treatment of proximal defects. METHODS: From January 2011 to May 2013, 10 patients (11 knees) were treated with total knee arthroplasties using the long-stem tibial component with metallic tibial wedge of knee prosthesis. All the patients were female and the average age was 67 years old (ranged, 60 to 77 years old). All the patients were osteoarthritis. All the patients were classified as T2A style. The patients were evaluated according to knee score system (KSS). RESULTS: All the patients were followed up for 12 months on average (ranged 3 to 29 months). The clinical outcome was assessed using KSS score, including knee pain score, knee stability score, knee range of motion score and knee walking score, knee stairs score. There were significantly differences at 6 weeks, 3 months, 6 months and 12 months between pre-and postoperative KSS score. CONCLUSION: The mechanical stability of tibial fixation in primary TKA is significantly increased by using the long-stem tibial component with metallic wedge of knee prosthesis, even in the presence of poor proximal bone.


Assuntos
Osteoartrite do Joelho/cirurgia , Tíbia/anormalidades , Idoso , Artroplastia do Joelho , Feminino , Humanos , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Prótese do Joelho , Masculino , Osteoartrite do Joelho/fisiopatologia , Amplitude de Movimento Articular , Tíbia/fisiopatologia , Tíbia/cirurgia
18.
Neurosciences (Riyadh) ; 21(2): 120-5, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-27094521

RESUMO

OBJECTIVE: To study the possible relationship between amyotrophic lateral sclerosis (ALS) patients and their susceptibility to serum ferritin level elevation. METHODS: We searched the PubMed, Springer, Medline, and OVID databases for any-language original research articles relating to serum ferritin levels in ALS patients published between June 2005 and June 2015. The search term used with `amyotrophic lateral sclerosis`, `ferritins`, `ferritin`, `iron`, `iron stores, `iron status, `iron intake`, and `iron consumption`. The meta-analysis software RevMan 5.0 was used for the heterogeneity test, and to test for the overall effect. RESULTS: Six case-control studies met our inclusion criteria including data from a total of 1813 participants. The mean difference of serum ferritin levels comparing ALS to healthy controls was 69.05 (95% confidence interval: 52.56-85.54; p<0.00001); heterogeneity: p=0.03; I2=50%. The findings indicate homology in the sensitivity analysis. Funnel plot assessment indicated publication bias. CONCLUSION: Our results suggest that ALS is positively associated with susceptibility to the elevation of serum ferritin levels; however, further evidence is required to support this.


Assuntos
Esclerose Lateral Amiotrófica/sangue , Ferritinas/sangue , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Chem Rec ; 16(2): 754-67, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26853768

RESUMO

Monometallic and dimetallic complexes with the ruthenium-amine conjugated structural unit have been prepared. These complexes display consecutive redox waves with low potentials and rich and intense absorptions in the near-infrared region. The electrochemical and spectroscopic properties can be modulated using substituents or auxiliary ligands with different electronic natures. Through simple functionalization, electropolymerized or monolayer thin films of these complexes have been prepared. These films display multistate near-infrared electrochromism with good contrast ratios and long optical retention times. In addition, flip-flop and flip-flap-flop memories have been demonstrated on the basis of these thin films.

20.
Chemistry ; 22(15): 5211-8, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-26771048

RESUMO

The construction of well-controlled porous materials is very challenging. Herein, we report the successful preparation of structurally defined porous membranes based on hexakistriphenylamine metallacycles through electropolymerization. The newly designed porous materials were characterized by the typical cyclic voltammograms, XPS, SEM, and TEM investigations. Further investigations revealed that the metallacycle-based polymer films displayed a good size-selective molecular-sieving behavior.

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