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1.
Clin Gastroenterol Hepatol ; 22(4): 778-788.e7, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38061410

RESUMEN

BACKGROUND & AIMS: Patients with cirrhosis secondary to chronic hepatitis C virus (HCV) are at risk for hepatocellular carcinoma (HCC) despite a sustained virological response (SVR). We examined whether post-SVR liver stiffness measurement (LSM) could be used to stratify HCC risk. METHODS: This was a retrospective cohort study of 1850 participants identified from the Veterans Health Administration, with HCV cirrhosis and SVR, followed up over 5099 person-years, from the time of post-SVR elastography until death, HCC, or the end of the study. RESULTS: The risk of HCC increased by 3% with every 1-kPa increase in LSM (adjusted hazard ratio [aHR], 1.03, 95% confidence interval [CI], 1.01-1.04; P < .001) and decreased with the number of years from SVR (aHR, 0.79; 95% CI, 0.70-0.90; P = .0003). The adjusted annual risk of HCC was 2.03% among participants with post-SVR LSM <10 kPa, 2.48% in LSM 10-14.9 kPa (aHR, 1.71; 95% CI, 1.01-2.88; P = .046), 3.22% for LSM 15-19.9 kPa (aHR, 1.59; 95% CI, 0.78-3.20; P = .20), 5.07% among LSM 20-24.9 kPa (aHR, 2.55; 95% CI, 1.30-5.01; P = .01), and 5.44% in LSM ≥25 kPa (aHR, 3.03; 95% CI, 1.74-5.26; P < .0001). The adjusted annual risk of HCC was < 0.4% in participants with LSM <5 kPa and without diabetes mellitus. CONCLUSIONS: LSM predicts rates of HCC in patients with HCV cirrhosis after SVR at multiple cutoff levels and offers a single test to predict portal hypertension-related complications and HCC. Patients with LSM <5 kPa in the absence of diabetes mellitus had a low risk of HCC in which surveillance could be discontinued.


Asunto(s)
Carcinoma Hepatocelular , Diabetes Mellitus , Diagnóstico por Imagen de Elasticidad , Hepatitis C Crónica , Neoplasias Hepáticas , Veteranos , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/etiología , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/etiología , Estudios Retrospectivos , Antivirales/uso terapéutico , Cirrosis Hepática/complicaciones , Cirrosis Hepática/tratamiento farmacológico , Respuesta Virológica Sostenida
2.
Inorg Chem ; 62(49): 20520-20527, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38033304

RESUMEN

In order to reveal the integrated effect of inorganic lattice structure disturbances and chiral ligands on the structure of tin halide hybrid materials, we show the synthesis, crystal growth, dissolution recrystallization structural transformation (DRST), optical properties, energy band structure, and nonlinear optical properties of a class of chiral tin bromide R/S-2-mpip[SnBr3]Br (2-mpip is 2-methylpiperazinium) and R/S-2-mpipSnBr6 for the first time. The formation of R/S-2-mpipSnBr6 in solution was interestingly caused by irreversible DRST of R/S-2-mpip[SnBr3]Br. The second-harmonic generation response of the new phase R-2-mpipSnBr6 is significantly enhanced compared to that of the initial phase R-2-mpip[SnBr3]Br. These structural transformations of chiral tin bromides reflect, to some extent, the DRST commonality of the tin halide family induced by oxidation and serve as a starting point for investigating the structural chirality and asymmetry of chiral metal hybrid halides.

3.
Inorg Chem ; 62(43): 17931-17939, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37831425

RESUMEN

Mn(II)-based hybrid halides have attracted great attention from the optoelectronic fields due to their nontoxicity, special luminescent properties, and structural diversity. Here, two novel organic-inorganic hybrid Mn(II)-based halide single crystals (1-mpip)MnCl4·3H2O and (1-mpip)2MnCl6 (1-mpip = 1-methylpiperazinium, C5H14N2+) were grown by a slow evaporation method in ambient atmosphere. Interestingly, (1-mpip)2MnCl6 single crystals exhibit the green emission with a PL peak at 522 nm and photoluminescence quantum yields (PLQYs) of ≈5.4%, whereas (1-mpip)MnCl4·3H2O single crystals exhibit no emission characteristics. More importantly, there exists a thermal-induced phase transformation from (1-mpip)MnCl4·3H2O to emissive (1-mpip)2MnCl6 at 372 K. Moreover, a reversible luminescent conversion between (1-mpip)MnCl4·3H2O and (1-mpip)2MnCl6 was simply achieved when heated to 383 K and placed in a humid environment or sprayed with water. This work not only deepens the understanding of the thermal-induced phase transformation and humidity-sensitive luminescent conversion of hybrid Mn(II)-based halides, but also provides a guidance for thermal and humidity sensing and anticounterfeiting applications of these hybrid materials.

4.
Small Methods ; 7(3): e2201365, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36642854

RESUMEN

The practical application of lead-free double perovskite Cs2 AgBiBr6 in photocatalytic H2 evolution is still restricted due to the low activity and poor stability. The rational design of lead-free halide double perovskites heterojunctions with efficient charge transfer and effective active sites is a potential route to achieve the ideal prospect. Herein, in this work an S-scheme heterojunction of Cs2 AgBiBr6 with enriched Br-vacancies and WO3 nanorods (VBr -Cs2 AgBiBr6 /WO3 ) obtaining excellent visible-light responsive photocatalytic H2 evolution performance and durable stability is reported. The S-scheme heterojunction driven by the unaligned Fermi levels of these two semiconductors ensures the efficient charge transfer at the interface, and density functional theory calculations reveal the enriched Br vacancies on Cs2 AgBiBr6 (022) surfaces introduced by atom thermal vibration provide effective active sites for hydrogen evolution. The optimized VBr -Cs2 AgBiBr6 /WO3 S-scheme photocatalyst exhibits the photocatalytic hydrogen evolution rate of 364.89 µmol g-1 h-1 which is 4.9-fold of bare VBr -Cs2 AgBiBr6 (74.44 µmol g-1 h-1 ) and presents long-term stability of 12 h continuous photocatalytic reaction. This work provides deep insights into the photocatalytic mechanism of VBr -Cs2 AgBiBr6 /WO3 S-scheme heterojunctions, which emerges a new strategy in the applications of perovskite-based photocatalysts.

5.
Inorg Chem ; 61(42): 16936-16943, 2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36205543

RESUMEN

Introducing electronegative species into organic constituents was considered to be one effective strategy for adjusting crystal symmetry and designing new nonlinear optical (NLO) materials. By substitution of C4 in piperidine (C5H11N) with electronegative oxygen, organic morpholine (C4H9NO) was easily obtained. Therefore, to design NLO crystals, we focused on combinations of stereochemically active lone-pair (SCALP) cation (Pb2+)-based chloride and bromide with morpholine molecules. In this work, two lead halide hybrid perovskite (C4H10NO)PbX3 (X = Cl, Br, abbreviated as MPbCl3 and MPbBr3, respectively) single crystals with moderate nonlinear optical properties were synthesized by a slow evaporation method. The two title crystals belong to orthorhombic space group P212121 with one-dimensional (1D) chainlike perovskite structures. Theoretical calculations revealed that the second harmonic generation (SHG) responses mainly originate from distorted {PbX6} octahedrons of the inorganic framework. Remarkably, moderate phase-matching SHG effects of about 0.70 and 0.81 times KH2PO4, large birefringences of 0.098 and 0.111 at 1064 nm, and large laser damage thresholds (LDTs) of 19.94 and 46.82 MW/cm2 were estimated for MPbCl3 and MPbBr3, respectively. This work provides a novel strategy for new purpose-designed hybrid NLO crystals by adjustment and modulation of chemical modification.

6.
Inorg Chem ; 61(38): 15247-15255, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36094329

RESUMEN

Organic-inorganic hybrid Pb-halide perovskites have attracted tremendous interest due to their potential application in photovoltaic and optoelectronic fields. However, the toxicity and poor stability of Pb-halide perovskites have become key bottlenecks toward their future commercialization and industrialization. Therefore, in this work, two novel hybrid lead-free perovskite nonlinear optical (NLO) crystals (2-AMP)2BiX7·H2O (X = Cl, Br) with high stability were successfully synthesized. Both the crystals belong to the orthorhombic P212121 space group, displaying a zero-dimensional perovskite structure. The thermal, environmental, and solvent atmospheric stabilities were comprehensively investigated, with high thermal stability up to 170 °C and high environmental and high solvent atmospheric stability observed for (2-AMP)2BiBr7·H2O. First-principles calculations were carried out to study the relationship of the structure and properties. A large birefringence of 0.1368@1064 nm was determined for (2-AMP)2BiBr7·H2O, which was derived from the strong aeolotropic conjugated π-electron distribution of planar 2-aminomethylpyridium. A second-harmonic generation (SHG) effect that was 0.25 and 0.32 times that of KH2PO4 (KDP) was measured for (2-AMP)2BiCl7·H2O and (2-AMP)2BiBr7·H2O, respectively, and the stronger SHG response of bromide was attributed to the larger distortions of {BiBr6} octahedrons. This work may offer new guidance for exploration of low toxicity and high stability of perovskite NLO materials.

7.
Inorg Chem ; 61(20): 8076-8082, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-35537082

RESUMEN

To design nonlinear optical (NLO) materials, we focused on combinations of d10 metal cation (Cd2+)-based chloride and morpholine molecules to form organic-inorganic hybrids. The O of morpholine containing lone-pair electrons can be integrated with Cd2+ by a ligand-to-metal charge transfer (LMCT) strategy to build acentric structures benefiting from the second-order Jahn-Teller effect. Introduction of the high-electronegativity chlorine can make polyhedrons of acentric crystals more distorted and conducive to a strong second harmonic generation (SHG) response. Therefore, (Morpholinium)2Cd2Cl6 crystals were constructed and synthesized by a solvent evaporation method. (Morpholinium)2Cd2Cl6 belongs to the orthorhombic P212121 space group and shows a one-dimensional (1D) structure with distorted [CdCl6] and [CdCl4O2] octahedrons. The short cutoff edge of (Morpholinium)2Cd2Cl6 was determined to be about 230 nm. The SHG response of (Morpholinium)2Cd2Cl6 exhibited an intensity of approximately 0.73 × KDP as estimated by the powder second harmonic generation technique. Furthermore, related theoretical calculations were performed to study the relationship of the band structure, refractive anisotropy, electronic state, and nonlinear optical response. Besides, (Morpholinium)2Cd2Cl6 showed relatively good thermal stability. This work can serve as a guide for the design and synthesis of new large NLO hybrid crystals with d10 transition metals.

8.
Inorg Chem ; 61(18): 6943-6952, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35485722

RESUMEN

Lead (Pb)-free halide hybrid materials have received a great deal of attention because of their potential in optoelectronic applications. However, heteroatom-based amine lead-free tin halide hybrid single crystals have not been well investigated yet. Detailed synthetic processes, growth, crystal structures, and stability of (ACH2CH2NH3)2SnBr6 (A = OH or SH) and (BCH2CH2NH3)2SnI4 (B = I or SH) single crystals were investigated. Interestingly, (IH3NCH2CH2SSCH2CH2NH3)2HPO3 exhibited orange-red photoluminescence (PL) at about 620 nm with an average PL lifetime of about 912 ns. (HSCH2CH2NH3)2SnI4 single crystals exhibited a PL peak at 620 nm with an average PL lifetime of about 0.607 ns. More importantly, (HSCH2CH2NH3)2SnI4 single crystals exhibited reversible red-black color transformations when exposed to a H3PO2 solution and an ambient atmosphere, which was attributed to oxidation from Sn2+ to Sn4+, rather than from I- to I3- (I2). The intriguing characteristics should provide guidance for further optoelectronic applications of these Pb-free halide hybrid materials.

9.
J Phys Chem Lett ; 13(11): 2567-2575, 2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-35286088

RESUMEN

Light-emitting diodes (LEDs) with the circularly polarized luminescence features have attracted attention to the promising applications ranging from solid-state lighting and displays to bioencoding and anticounterfeiting. The prerequisite of circularly polarized luminescence is highly emissive chiral materials. Here, we demonstrated that (R/S-MBA)4Cu4I8·2H2O (MBA = α-methylbenzylaminium) and acentric Gua6Cu4I10 (Gua = guanidinium) single crystals were grown on the basis of Gua3Cu2I5 by the slow evaporation method. (R/S-MBA)4Cu4I8·2H2O single crystals exhibited excellent circularly polarized luminescence (CPL) characteristics. More importantly, ultraviolet-pumped LEDs (UV-LEDs) based on (R/S-MBA)4Cu4I8·2H2O and Gua6Cu4I10 single crystals exhibit a higher optical selectivity when exposed to right-handed and left-handed circular polarization (RCP and LCP) conditions. (S-MBA)4Cu4I8·2H2O single crystals and Gua6Cu4I10 single crystals induced by the (R)-MBA cation exhibit the different polarized light intensities at PL peak positions in different λ/4 waveplate polarizer angle directions, which provides new possibilities for the further applications from 3D displays to spintronics, as well as anticounterfeiting.

10.
Nanomaterials (Basel) ; 11(4)2021 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-33921639

RESUMEN

In recent years, high-performance photodetectors have attracted wide attention because of their important applications including imaging, spectroscopy, fiber-optic communications, remote control, chemical/biological sensing and so on. Nanostructured perovskites are extremely suitable for detective applications with their long carrier lifetime, high carrier mobility, facile synthesis, and beneficial to device miniaturization. Because the structure of the device and the dimension of nanostructured perovskite have a profound impact on the performance of photodetector, we divide nanostructured perovskite into 2D, 1D, and 0D, and review their applications in photodetector (including photoconductor, phototransistor, and photodiode), respectively. The devices exhibit high performance with high photoresponsivity, large external quantum efficiency (EQE), large gain, high detectivity, and fast response time. The intriguing properties suggest that nanostructured perovskites have a great potential in photodetection.

11.
ACS Appl Mater Interfaces ; 12(33): 37713-37721, 2020 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-32814401

RESUMEN

To study stability issues of three-dimensional perovskites, there is a strategy to introduce the thiocyanate ion (SCN-) into CH3NH3PbI3 (MAPbI3) to solve these problems. Here, we report the bulk growth of layered perovskite MA2Pb(SCN)2I2 single crystals by different growth methods in an ambient atmosphere. We also investigate the structural determination and refinements, band gap, and photoluminescence of MA2Pb(SCN)2I2 single crystals. More importantly, the phase transition and stability of MA2Pb(SCN)2I2 are systematically demonstrated. MA2Pb(SCN)2I2 undergo the reversible single-crystal to single-crystal phase transition in the orthorhombic systems from the space group Pmmn (no. 59) to the space group Pmn21 (no. 31) at low temperature. Moreover, the temperature-dependent recovery behaviors of MA2Pb(SCN)2I2 single crystals, powders, and thin films at high temperature are studied in detail. Besides, the moisture stability of MA2Pb(SCN)2I2 is described when exposed to moisture condition by the experiment and theoretical calculations. It would be interesting to not only conduct a comprehensive study on the crystal structures and the phase transition processes of layered perovskites but also provide guidance for further optoelectronic applications of these perovskite materials.

12.
J Phys Chem Lett ; 11(5): 1689-1696, 2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-32039602

RESUMEN

Motivated by the chirality research of the hybrid halide perovskite, we reported the controllable growth of single crystals of (R)-, (S)-, and (R,S)-C6H5CH(CH3)NH3 (MBA)-based lead (Pb) halide perovskites. The crystal structures were redetermined and further refined to clarify the previously ambiguous crystal structure problems. We further investigated the chiral optical properties of these single crystals including nonlinear optical (NLO) properties and photoluminescence (PL) properties. The as-fabricated (R)- and (S)-MBAPbBr3 single crystals not only show notable circular dichroism (CD) signals in the absorption spectra but also exhibit obvious circularly polarized luminescence (CPL) characteristics. The available chiral hybrid perovskite single crystals open up the possibility to study these intrinsic chirality properties for optoelectronic applications.

13.
J Nanosci Nanotechnol ; 20(3): 1643-1650, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31492326

RESUMEN

Lithium sulfur batteries (Li-S) have been deemed to be the promising energy-storage systems. Nevertheless, the shuttle effect caused by diffusion of polysulfides limit their application. In this work, the different dimensions of g-C3N4 nanomaterials (2D g-C3N4 nanosheets and 3D g-C3N4 nanomesh) were doped in S electrode. Because of the large specific surface area of 3D g-C3N4 nanomesh and strong chemical adsorption of polysulfides can provide better effect for inhibition of shuttling effect and its proper electron passage make electrochemical kinetics of lithium-sulfur battery enhanced. The discharge specific capacity of the 3D g-C3N4 battery is up to 731 mAh/g and longer cycling performance with 540 mAh/g after 180 cycles. This experiment paves the way forward for the application of g-C3N4 on Li-S batteries.

14.
Front Chem ; 7: 748, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31828058

RESUMEN

Lithium (Li) metal is regarded as the ideal anode for rechargeable Li-metal batteries such as Li-S and Li-air batteries. A series of problems caused by Li dendrites, such as low Coulombic efficiency (CE) and a short circuit, have limited the application of Li-metal batteries. In this study, a graphene-modified three-dimensional (3D) Copper (Cu) current collector is addressed to enable dendrite-free Li deposition. After Cu foam is immersed into graphene oxide (GO) suspension, a spontaneous reduction of GO, induced by Cu, generates reduced graphene oxide on a 3D Cu (rGO@Cu) substrate. The rGO@Cu foam not only provides large surface area to accommodate Li deposition for lowering the local effective current density, but also forms a rGO protective layer to effectively control the growth of Li dendrites. As current collector, the rGO@Cu foam shows superior properties than commercial Cu foam and planar Cu foil in terms of cycling stability and CE. The rGO@Cu foam delivers a CE as high as 98.5% for over 350 cycles at the current density of 1 mA cm-2. Furthermore, the full cell using LiFePO4 as cathode and Li metal as anode with rGO@Cu foam as current collector (LiFePO4/rGO@Cu-Li) is assembled to prove the admirable capacities and indicates commercialization of Li-metal batteries.

15.
Nanoscale ; 11(44): 21061-21067, 2019 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-31667484

RESUMEN

Lanthanide-based coordination polymers (CPs) have received great attention due to their tuneable structures and excellent luminescence properties. However, limited by the stability and micro/nanoscale morphology, a very small number of lanthanide-based CPs have been used for photonic applications. Herein, we present the synthesis of Eu-based CPs (compound 2) with highly regular one-dimensional (1D) microrod morphology by in situ structure transformation from compound 1. Moreover, the Eu-based CP microrods have an excellent stability and a high photoluminescence quantum yield (PLQY), and the distance-dependent PL spectra also exhibited typical characteristics of photoactive waveguides with a low optical-loss coefficient (0.00894 dB µm-1) during propagation. These intriguing behaviors not only extend the research field of optical waveguides through lanthanide-based CPs, but also provide an opportunity for further application in optical communication systems.

16.
Adv Mater ; 31(37): e1903175, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31379034

RESUMEN

Construction of high-performance organic light-emitting transistors (OLETs) remains challenging due to the limited desired organic semiconductor materials. Here, two superior high mobility emissive organic semiconductors, 2,6-diphenylanthracene (DPA) and 2,6-di(2-naphthyl) anthracene (dNaAnt), are introduced into the construction of OLETs. By optimizing the device geometry for balanced ambipolar efficient charge transport and using high-quality DPA and dNaAnt single crystals as active layers, high-efficiency single-component OLETs are successfully fabricated, with the demonstration of strong and spatially controlled light emission within both p- and n- conducting channels and output of high external quantum efficiency (EQE). The obtained EQE values in current devices are approaching 1.61% for DPA-OLETs and 1.75% for dNaAnt-based OLETs, respectively, which are the highest EQE values for single-component OLETs in the common device configuration reported so far. Moreover, high brightnesses of 1210 and 3180 cd m-2 with current densities up to 1.3 and 8.4 kA cm-2 are also achieved for DPA- and dNaAnt-based OLETs, respectively. These results demonstrate the great potential applications of high mobility emissive organic semiconductors for next-generation rapid development of high-performance single-component OLETs and their related organic integrated electro-optical devices.

17.
Angew Chem Int Ed Engl ; 55(10): 3447-50, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26889919

RESUMEN

Hybrid perovskites have generated a great deal of interest because of their potential in photovoltaic applications. However, the toxicity of lead means that there is interest in finding a nontoxic substitute. Bulk single crystals of both cubic CH3NH3 SnI3 and CH(NH2)2 SnI3 were obtained by using the top-seeded solution growth method under an ambient atmosphere. Structural refinement, band gap, thermal properties, and XPS measurements of CH3NH3 SnI3 and CH(NH2)2 SnI3 single crystals are also reported in detail. These results should pave the way for further applications of CH3NH3 SnI3 and CH(NH2)2 SnI3.

18.
Dalton Trans ; 42(27): 9893-7, 2013 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-23695292

RESUMEN

This paper reports, for the first time, the nonlinear optical property of ß-HgBrCl, which was synthesized by a reaction of Hg2Cl2 and Br2 in EtOH. This reaction also gave α-HgBrCl. And the single crystal structures of both α- and ß-HgBrCl are presented and compared. ß-HgBrCl shows phase-matchable powder second harmonic generation (SHG) effect of about 2 times that of KH2PO4 (KDP). Its absorption edge in UV-vis spectrum locates at 366 nm, implying a wide band gap and therefore higher laser damage threshold. It also exhibits a relatively wide transparent window (from 0.4 to 20 µm) and relatively good thermal stability.


Asunto(s)
Bromuros/química , Cloruros/química , Mercurio/química , Cristalografía por Rayos X , Modelos Moleculares , Estructura Molecular , Fenómenos Ópticos , Difracción de Polvo , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Espectroscopía Infrarroja Corta
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