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1.
Nanoscale ; 11(47): 22899-22906, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31763640

RESUMO

All-inorganic perovskite CsPbBr3-Cs4PbBr6 composite nanocrystals (NCs) were synthesized via a convenient solution process without inert gas protection and systematically studied as green phosphors for light emitting diode (LED) applications. While colloidal composite NCs emit green color with an emission peak at around 515 nm, their thin films on top of blue GaN chips exhibit a redshift of ∼15-20 nm due to subsequential aggregation in solid state. The Commission Internationale De I'eclairage (CIE) chromaticity coordinates of the green LEDs assembled by composite NCs reached (0.201, 0.746) with nearly 100% green ratio. Moreover, the pure green LED displayed a luminous efficiency of 45 lm W-1 under 10 mA driving current. The colloidal CsPbBr3-Cs4PbBr6 composite NCs have the photoluminescence quantum yield (PLQY) as high as 74%. The high PLQY originates from cubic CsPbBr3 NCs well passivated by the zero-dimensional Cs4PbBr6 matrix, substantially suppressing the nonradiative recombination. The comparison between the green LEDs fabricated with pure and composite perovskites imply that the CsPbBr3-Cs4PbBr6 composites with higher quantum yield could be an effective way to get the brightness and the stability of pure green LEDs.

2.
Nanomaterials (Basel) ; 9(9)2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31540315

RESUMO

Two-dimensional (2D) tungsten disulfide (WS2) has inspired great efforts in optoelectronics, such as in solar cells, light-emitting diodes, and photodetectors. However, chemical vapor deposition (CVD) grown 2D WS2 domains with the coexistence of a discontinuous single layer and multilayers are still not suitable for the fabrication of photodetectors on a large scale. An emerging field in the integration of organic materials with 2D materials offers the advantages of molecular diversity and flexibility to provide an exciting aspect on high-performance device applications. Herein, we fabricated a photodetector based on a 2D-WS2/organic semiconductor materials (mixture of the (Poly-(N, N'-bis-4-butylphenyl-N, N'-bisphenyl) benzidine and Phenyl-C61-butyric acid methyl ester (Poly-TPD/PCBM)) heterojunction. The application of Poly-TPD/PCBM organic blend film enhanced light absorption, electrically connected the isolated WS2 domains, and promoted the separation of electron-hole pairs. The generated exciton could sufficiently diffuse to the interface of the WS2 and the organic blend layers for efficient charge separation, where Poly-TPD was favorable for hole carrier transport and PCBM for electron transport to their respective electrodes. We show that the photodetector exhibited high responsivity, detectivity, and an on/off ratio of 0.1 A/W, 1.1 × 1011 Jones, and 100, respectively. In addition, the photodetector showed a broad spectral response from 500 nm to 750 nm, with a peak external quantum efficiency (EQE) of 8%. Our work offers a facile solution-coating process combined with a CVD technique to prepare an inorganic/organic heterojunction photodetector with high performance on silicon substrate.

3.
Biomark Med ; 12(8): 871-880, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29900754

RESUMO

AIM: To explore circulating miRNA-302 family members for acute heart failure (AHF) diagnosis. METHODS: Three groups of subjects, in other words, AHF patients, AHF free patients and healthy controls were recruited. Circulating levels of miR-302 family members were measured and analyzed for AHF diagnosis. RESULTS: Plasma miR-302s except miR-302f were significantly elevated in AHF patients. MiR-302b-3p had the highest area under curve value of 0.87. There were strong positive correlations between miR-302s and NT-proBNP levels. MiR-302b-3p levels were significantly higher in left ventricular ejection fraction ≤45% and New York Heart Association class IV patients compared with left ventricular ejection fraction >45% and New York Heart Association class II patients, respectively. CONCLUSION: Levels of circulating miR-302s, miR-302b-3p in particular, could be potentially applied for AHF diagnosis and the differentiation of disease severity.


Assuntos
Insuficiência Cardíaca , MicroRNAs/sangue , Volume Sistólico , Doença Aguda , Idoso , Biomarcadores/sangue , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
4.
ACS Appl Mater Interfaces ; 10(19): 16596-16604, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29687705

RESUMO

We report a facile transfer method to fabricate flexible photodetectors directly on tape, wherein the films formed by different processes were integrated together. The tape-based photodetectors with CdS nanowire (NW) active layers exhibited good performances as those fabricated by conventional processes. The obvious persistent photocurrent in our device was eliminated by introducing a conductive polymer poly(3,4-ethylenedioxythiophene)polystyrene sulfonate (PEDOT:PSS) onto the CdS NW layer. By adjusting the concentration of the PEDOT:PSS aqueous solution, a device with a fast response, ultrashort decay time, and relatively large photocurrent was obtained. The decay times were 11.59 and 6.64 ms for devices using electrodes of silver NWs and gold, respectively. These values are much shorter than the shortest decay times (on the order of hundreds of milliseconds) reported previously.

5.
J Med Chem ; 60(11): 4657-4664, 2017 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-28498655

RESUMO

Modification of a gut restricted class of benzimidazole DGAT1 inhibitor 1 led to 9 with good oral bioavailability. The key structural changes to 1 include bioisosteric replacement of the amide with oxadiazole and α,α-dimethylation of the carboxylic acid, improving DGAT1 potency and gut permeability. Since DGAT1 is expressed in the small intestine, both 1 and 9 can suppress postprandial triglycerides during acute oral lipid challenges in rats and dogs. Interestingly, only 9 was found to be effective in suppressing body weight gain relative to control in a diet-induced obese dog model, suggesting the importance of systemic inhibition of DGAT1 for body weight control. 9 has advanced to clinical investigation and successfully suppressed postprandial triglycerides during an acute meal challenge in humans.


Assuntos
Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Dieta Hiperlipídica , Inibidores Enzimáticos/farmacologia , Obesidade/fisiopatologia , Triglicerídeos/sangue , Ganho de Peso/efeitos dos fármacos , Administração Oral , Adolescente , Adulto , Animais , Cães , Método Duplo-Cego , Descoberta de Drogas , Inibidores Enzimáticos/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Período Pós-Prandial , Ratos , Ratos Sprague-Dawley , Adulto Jovem
6.
Nanoscale ; 8(36): 16440-8, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27602563

RESUMO

Two-photon (TP) three-dimensional solid matrices have potential applications in high density optical data reading and storage, infrared-pumped visible displays, lasers, etc. Such technologies will benefit greatly from the advantageous properties of TP materials including tunable emission wavelength, photostability, and simple chemical processing. Here, this ideal TP solid is made possible by using a facile sol-gel process to engineer colloid quantum dots into silica gel glass. Characterization using an open-aperture Z-scan technique shows that the solid matrices exhibited significant TP optical properties with a TP absorption coefficient of (9.41 ± 0.39) × 10(-2) cm GW(-1) and a third-order nonlinear figure of merit of (7.30 ± 0.30) × 10(-14) esu cm. In addition, the dependence of the TP properties on high-temperature thermal treatment is studied in detail to obtain a clear insight for practical applications. The results illustrate that the sample can maintain stable TP performance below the synthesis temperature of the CdTe/CdS colloidal quantum dots. Furthermore, the mechanisms for thermal quenching of photoluminescence under different temperature regimes are clarified as a function of the composition.

7.
Sci Rep ; 6: 19273, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26763937

RESUMO

We have developed a novel but simple approach to obtain ZnO microcombs with parallelogram stems and elongated hexagonal branches. We found that the present elongated hexagonal microcavity exhibited quite different features for its optical resonant modes due to the broken hexagonal symmetry. The resonant mode evolution of such microcavity was investigated systemically by using a spatially resolved spectroscopic technique. Theoretical analyses based on the plane wave mode and FEM simulations agreed well with the experimental results. We believe that our research allows us to have a deeper understanding of the controllable growth of novel optical cavities and the shape-dependent optical resonant modes.

8.
Bioorg Med Chem Lett ; 26(4): 1245-8, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26804232

RESUMO

Diamide compounds were identified as potent DGAT1 inhibitors in vitro, but their poor molecular properties resulted in low oral bioavailability, both systemically and to DGAT1 in the enterocytes of the small intestine, resulting in a lack of efficacy in vivo. Replacing an N-alkyl group on the diamide with an N-aryl group was found to be an effective strategy to confer oral bioavailability and oral efficacy in this lipophilic diamide class of inhibitors.


Assuntos
Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Diamida/química , Inibidores Enzimáticos/química , Animais , Linhagem Celular Tumoral , Diacilglicerol O-Aciltransferase/metabolismo , Diamida/síntese química , Diamida/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Meia-Vida , Humanos , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
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