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1.
Biomedicines ; 12(6)2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38927463

RESUMEN

Chronic inflammatory lung diseases are characterized by disease-specific extracellular matrix accumulation resulting from an imbalance of matrix metalloproteinases (MMPs) and their inhibitors. Zinc is essential for the function of MMPs, and zinc deficiency has been associated with enhanced tissue remodeling. This study assessed if zinc iodide (ZnI) supplementation through dimethyl sulfoxide (DMSO) modifies the action of MMPs in isolated human lung fibroblasts. The expression and activity of two gelatinases, MMP-2 and MMP-9, were determined by gelatin zymography and enzyme-linked immuno-sorbent assay (ELISA). Collagen degradation was determined by cell-based ELISAs. Collagen type I and fibronectin deposition was stimulated by human recombinant tumor growth factor ß1 (TGF-ß1). Untreated fibroblasts secreted MMP-2 but only minute amounts of MMP-9. TGF-ß1 (5 ng/mL) reduced MMP-2 secretion, but stimulated collagen type I and fibronectin deposition. All the effects of TGF-ß1 were significantly reduced in cells treated with ZnI-DMSO over 24 h, while ZnI and DMSO alone had a lower reducing effect. ZnI-DMSO alone did not increase MMP secretion but enhanced the ratio of active to inactive of MMP-2. ZnI alone had a lower enhancing effect than ZnI-DMSO on MMP activity. Furthermore, MMP-2 activity was increased by ZnI-DMSO and ZnI in the absence of cells. Soluble collagen type I increased in the medium of ZnI-DMSO- and ZnI-treated cells. Blocking MMP activity counteracted all the effects of ZnI-DMSO. Conclusion: The data suggest that the combination of ZnI with DMSO reduces fibrotic processes by increasing the degradation of collagen type I by up-regulating the activity of gelatinases. Thus, the combination of ZnI with DMSO might be considered for treatment of fibrotic disorders of the lung. DMSO supported the beneficial effects of ZnI.

2.
Artículo en Inglés | MEDLINE | ID: mdl-37903333

RESUMEN

Many cathode materials store zinc ions based on the intercalation reaction mechanism in neutral aqueous Zn-ion batteries, and the structural design of the cathodes has been stuck in the curing mode by extending the ion diffusion channel. Here, we first develop halide ions to unlock the electrochemical activity of conversion-type Bi2O3 in aqueous Zn-ion batteries. Notably, the iodide ion shows the best performance compatibility with the Bi2O3 cathode. The electrochemical reaction mechanism studies show that iodide ions can be regarded as a redox medium to reduce the charge-transfer activation energy and motivate the conversion of Bi2O3 from Bi3+ to Bi0 during the cycle. Unsurprising, the discharge-specific capacity can reach 436.8 mAh g-1 at 0.5 A g-1 and achieve a cyclic lifespan of 6000 cycles at a current density of 3 A g-1. The activation of the Bi2O3 conversion reaction by iodide ions is of great significance for broadening the research range of ZIB cathode materials.

3.
ACS Appl Mater Interfaces ; 15(29): 34711-34725, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37433014

RESUMEN

Aqueous redox flow battery systems that use a zinc negative electrode have a relatively high energy density. However, high current densities can lead to zinc dendrite growth and electrode polarization, which limit the battery's high power density and cyclability. In this study, a perforated copper foil with a high electrical conductivity was used on the negative side, combined with an electrocatalyst on the positive electrode in a zinc iodide flow battery. A significant improvement in the energy efficiency (ca. 10% vs using graphite felt on both sides) and cycling stability at a high current density of 40 mA cm-2 was observed. A long cycling stability with a high areal capacity of 222 mA h cm-2 is obtained in this study, which is the highest reported areal capacity for zinc-iodide aqueous flow batteries operating at high current density, in comparison to previous studies. Additionally, the use of a perforated copper foil anode in combination with a novel flow mode was discovered to achieve consistent cycling at exceedingly high current densities of >100 mA cm-2. In situ and ex situ characterization techniques, including in situ atomic force microscopy coupled with in situ optical microscopy and X-ray diffraction, are applied to clarify the relationship between zinc deposition morphology on the perforated copper foil and battery performance in two different flow field conditions. With a portion of the flow going through the perforations, a significantly more uniform and compact zinc deposition was observed compared to the case where all of the flow passed over the surface of the electrode. Results from modeling and simulation support the conclusion that the flow of a fraction of electrolyte through the electrode enhances mass transport, enabling a more compact deposit.

4.
ACS Appl Mater Interfaces ; 14(27): 30907-30913, 2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35772123

RESUMEN

Herein, we propose a novel design of photo-assisted battery desalination, which provides the tri-function within a single device including the photo-assisted charge (electrical energy saving), energy storage, and desalination (salt removal). The photoelectrode (N719/TiO2) is directly integrated into the zinc-iodide (Zn-I) battery with the desalination stream in the middle portion of the device. This architecture can provide a reduced energy consumption up to 50%, an energy output of 42 W h mol-1NaCl, and a desalination rate of 13 µg/cm2 min-1. This work is significant for the inter-discipline study of the redox flow energy storage and energy-saving desalination.

5.
Nano Lett ; 22(6): 2538-2546, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35266715

RESUMEN

Aqueous zinc iodide (Zn-I2) batteries are promising large-scale energy-storage devices. However, the uncontrollable diffuse away/shuttle of soluble I3- leads to energy loss (low Coulombic efficiency, CE), and poor reversibility (self-discharge). Herein, we employ an ordered framework window within a zeolite molecular sieve to restrain I3- crossover and prepare zeolite molecular sieve particles into compact, large-scale, and flexible membranes at the engineering level. The as-prepared membrane can confine I3- within the catholyte region and restrain its irreversible escape, which is proved via space-resolution and electrochemical in situ time-resolution Raman technologies. As a result, overcharge/self-discharge and Zn corrosion are effectively controlled by zeolite separator. After replacing the typically used glass fiber separator to a zeolite membrane, the CE of Zn-I2 battery improves from 78.9 to 98.6% at 0.2 A/g. Besides, after aging at the fully charged state for 5.0 h, self-discharge is restrained and CE is enhanced from 44.0 to 85.65%. Moreover, the Zn-I2 cell maintains 91.0% capacity over 30,000 cycles at 4.0 A/g.

6.
ACS Appl Mater Interfaces ; 13(35): 41563-41572, 2021 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-34428017

RESUMEN

Among the aqueous redox flow battery systems, redox chemistries using a zinc negative electrode have a relatively high energy density, but the potential of achieving high power density and long cycle life is hindered by dendrite growth at the anode. In this study, a new cell design with a narrow gap between electrode and membrane was applied in a zinc-iodide flow battery. In this design, some of the electrolyte flows over the electrode surface and a fraction of the flow passes through the porous felt electrode in the direction of current flow. The flow battery was tested under constant current density over 40 cycles, and the efficiency, discharge energy density, and power density of the battery were significantly improved compared to conventional flow field designs. The power density obtained in this study is one of the highest power densities reported for the zinc-iodide battery. The morphology of the zinc deposition was studied using scanning electron microscopy and optical profilometry. It was found that the flow through the electrode led to a thinner zinc deposit with lower roughness on the surface of the electrode, in comparison to the case where there was no flow through the electrode. In addition, inhibition of dendrite formation enabled operation at a higher range of current density. Ex situ tomographic measurements were used to image the zinc deposited on the surface and inside the porous felt. Volume rendering of graphite felt from X-ray computed tomography images showed that in the presence of flow through the electrode, more zinc deposition occurred inside the porous felt, resulting in a compact and thinner surface deposit, which may enable higher battery capacity and improved performance.

7.
Adv Mater ; 32(38): e2004240, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32797719

RESUMEN

The introduction of the redox couple of triiodide/iodide (I3 - /I- ) into aqueous rechargeable zinc batteries is a promising energy-storage resource owing to its safety and cost-effectiveness. Nevertheless, the limited lifespan of zinc-iodine (Zn-I2 ) batteries is currently far from satisfactory owing to the uncontrolled shuttling of triiodide and unfavorable side-reactions on the Zn anode. Herein, space-resolution Raman and micro-IR spectroscopies reveal that the Zn anode suffers from corrosion induced by both water and iodine species. Then, a metal-organic framework (MOF) is exploited as an ionic sieve membrane to simultaneously resolve these problems for Zn-I2 batteries. The multifunctional MOF membrane, first, suppresses the shuttling of I3 - and restrains related parasitic side-reaction on the Zn anode. Furthermore, by regulating the electrolyte solvation structure, the MOF channels construct a unique electrolyte structure (more aggregative ion associations than in saturated electrolyte). With the concurrent improvement on both the iodine cathode and the Zn anode, Zn-I2 batteries achieve an ultralong lifespan (>6000 cycles), high capacity retention (84.6%), and high reversibility (Coulombic efficiency: 99.65%). This work not only systematically reveals the parasitic influence of free water and iodine species to the Zn anode, but also provides an efficient strategy to develop long-life aqueous Zn-I2 batteries.

8.
Med Hypotheses ; 143: 109866, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32473509

RESUMEN

Zinc Iodide and Dimethyl Sulfoxide compositions are proposed as therapeutic agents to treat and prevent chronic and acute viral infections including SARS-CoV-2 infected patients. The therapeutic combinations have a wide range of virucidal effects on DNA and RNA containing viruses. The combinations also exhibit anti-inflammatory, immunomodulating, antifibrotic, antibacterial, antifungal and antioxidative effects. Given the fact that Zinc Iodide has been used as an oral antiseptic agent and DMSO has been already proven as a safe pharmaceutical solvent and therapeutic agent, we hypothesize that the combination of these two agents can be applied as an effective, safe and inexpensive treatment for SARS-CoV-2 and other viral infection. The therapeutic compound can be applied as both etiological and pathogenesis therapy and used as an effective and safe antiseptic (disinfectant) for human and animals as well.


Asunto(s)
Infecciones por Coronavirus/tratamiento farmacológico , Dimetilsulfóxido/administración & dosificación , Desinfectantes/administración & dosificación , Yoduros/administración & dosificación , Neumonía Viral/tratamiento farmacológico , Compuestos de Zinc/administración & dosificación , Animales , Antiinflamatorios/administración & dosificación , Antioxidantes/administración & dosificación , Antivirales/administración & dosificación , Betacoronavirus , COVID-19 , Quimioterapia Combinada , Humanos , Inflamación , Pandemias , SARS-CoV-2 , Solventes , Virosis/tratamiento farmacológico , Tratamiento Farmacológico de COVID-19
9.
ACS Appl Mater Interfaces ; 11(19): 17555-17562, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30990007

RESUMEN

We present a one-step method to produce air-stable, large-grain mixed cationic lead perovskite films and powders under ambient conditions. The introduction of 2.5 % of Zn(II), confirmed by X-ray diffraction (XRD), results in stable thin films which show the same absorption and crystal structure after 2 weeks of storage under ambient conditions. Next to prolonged stability, the introduction of Zn(II) affects photophysical properties, reducing the bulk defect density, enhancing the photoluminescence (PL), and extending the charge carrier lifetime. Furthermore, 3-chloropropylamine hydrochloride is applied as the film-forming agent. The presence of this amine hydrochloride additive results in highly oriented and large crystal domains showing an ulterior improvement of PL intensity and lifetime. The material can also be prepared as black precursor powder by a solid-solid reaction under ambient conditions and can be pressed into a perovskite pellet. The prolonged stability and the easy fabrication in air makes this material suitable for large-scale, low-cost processing for optoelectronic applications.

10.
Beilstein J Org Chem ; 14: 1229-1237, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29977391

RESUMEN

We present a successful deoxygenation reaction of ortho-1,3-dithianylaryl(aryl)methanols which enables a selective removal of the secondary hydroxy group in presence of the 1,3-dithianyl moiety under reductive conditions. This reaction proceeds well with ZnI2/Na(CN)BH3 in dichloroethane or benzene for both unsubstituted and substituted aryls (by electron-rich groups). This is leading to formyl-protected diarylmethanes with potential application in the synthesis of new pharmaceuticals and optoelectronic materials. This synthetic approach gives an access to a wide variety of functionalized ortho-1,3-dithianylaryl(aryl)methanes in 26-95% yields and is recommended for the substrates containing sulfur atoms, for which transition metal-induced reactions fail.

11.
ACS Nano ; 12(7): 6648-6656, 2018 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-29975504

RESUMEN

The electronic and optical properties of two-dimensional layered materials allow the miniaturization of nanoelectronic and optoelectronic devices in a competitive manner. Even larger opportunities arise when two or more layers of different materials are combined. Here, we report on an ultrafast energy efficient strategy, using laser irradiation, which allows bulk synthesis of crystalline single-layered lead iodide in the cavities of carbon nanotubes by forming cylindrical van der Waals heterostructures. In contrast to the filling of van der Waals solids into carbon nanotubes by conventional thermal annealing, which favors the formation of inorganic nanowires, the present strategy is highly selective toward the growth of monolayers forming lead iodide nanotubes. The irradiated bulk material bearing the nanotubes reveals a decrease of the resistivity as well as a significant increase in the current flow upon illumination. Both effects are attributed to the presence of single-walled lead iodide nanotubes in the cavities of carbon nanotubes, which dominate the properties of the whole matrix. The present study brings in a simple, ultrafast and energy efficient strategy for the tailored synthesis of rolled-up single-layers of lead iodide (i.e., single-walled PbI2 nanotubes), which we believe could be expanded to other two-dimensional (2D) van der Waals solids. In fact, initial tests with ZnI2 already reveal the formation of single-walled ZnI2 nanotubes, thus proving the versatility of the approach.

12.
Acta Crystallogr C Struct Chem ; 74(Pt 3): 342-350, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29504564

RESUMEN

Three zinc iodide complexes based on phosphane ligands, namely diiodidobis(triphenylphosphane-κP)zinc(II), [ZnI2(C18H15P2)2], (1), diiodidobis[tris(4-methylphenyl)phosphane-κP]zinc(II), [ZnI2(C21H21P2)2], (2), and [bis(diphenylphosphoryl)methane-κ2O,O']zinc(II) tetraiodidozinc(II), [Zn(C25H22O2P2)3][ZnI4], (3), have been synthesized and characterized. Single-crystal X-ray diffraction revealed that the structures of (1) and (2) are both mononuclear four-coordinated ZnI2 complexes containing two monodentate phosphane ligands, respectively. Surprisingly, (2) spontaneously forms an acentric structure, suggesting it might be a potential second-order NLO material. The crystal structure of complex (3) is composed of two parts, namely a [Zn(dppmO2)3]2+ cation [dppmO2 is bis(diphenylphosphoryl)methane] and a [ZnI4]2- anion. The UV-Vis absorption spectra, thermal stabilities and photoluminescence spectra of the title complexes have also been studied. Time-dependent density functional theory (TD-DFT) calculations reveal that the low-energy UV absorption and the corresponding light emission both result from halide-ligand charge-transfer (XLCT) excited states.

13.
Artículo en Inglés | MEDLINE | ID: mdl-27037763

RESUMEN

Shakila and Kalainathan report on the synthetic and structural aspects of a zinc iodide complex with Schiff based ligand, which exhibits room temperature ferromagnetism. In this comment, many points of criticism, concerning the characterization of this so called zinc iodide complex of Schiff based ligand are highlighted to prove that the title paper is completely erroneous.


Asunto(s)
Antiinfecciosos , Bases de Schiff/química , Ligandos , Análisis Espectral , Temperatura , Zinc/química
14.
J Obstet Gynaecol Res ; 40(7): 1833-9, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25056459

RESUMEN

AIM: Langerhans cells (LC) are antigen-presenting cells present in tissues with high antigenic exposure. Their role in the upper female reproductive tract is not fully understood. This study aims to determine the distribution and morphology of LC in the normal and post-partum human uterine tubes and uterus by staining with the specific LC markers, CD1a and zinc iodide-osmium (ZIO), and to determine their association with helper and cytotoxic T cells. MATERIAL AND METHODS: Normal and post-partum uterine tube and uterine specimens were stained with CD1a and ZIO and their morphology and distribution noted. Double immune staining with CD1a-CD4 and CD1a-CD8 in post-partum uterine tube were also done. RESULTS: It was noted that CD1a-positive cells were significantly fewer and smaller in diameter than ZIO-positive cells in the uterine tube and both types of cells were significantly more prevalent in post-partum tubes. Perivascular clusters of ZIO-positive cells were seen in the post-partum tubes. Close association of CD1a-positive cells with CD4- and CD8-positive T cells was noted in the post-partum uterine tube. In the uterus, scanty CD1a-positive cells were present in the surface and glandular epithelium and endometrial stroma. ZIO-positive cells were absent. CONCLUSION: This study suggests that CD1a-positive and ZIO-positive cells may be different subsets of LC that are needed for presentation of antigen to immunocompetent cells. Their respective functions are yet to be determined.


Asunto(s)
Trompas Uterinas/inmunología , Células de Langerhans/inmunología , Útero/inmunología , Adulto , Antígenos CD1/metabolismo , Biomarcadores/metabolismo , Tamaño de la Célula , Endometrio/citología , Endometrio/inmunología , Endometrio/metabolismo , Endometrio/patología , Trompas Uterinas/citología , Trompas Uterinas/metabolismo , Trompas Uterinas/patología , Femenino , Humanos , Histerectomía , Células de Langerhans/citología , Células de Langerhans/metabolismo , Células de Langerhans/patología , Periodo Posparto , Esterilización Tubaria , Linfocitos T Citotóxicos/citología , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/metabolismo , Linfocitos T Citotóxicos/patología , Linfocitos T Colaboradores-Inductores/citología , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Linfocitos T Colaboradores-Inductores/patología , Útero/citología , Útero/metabolismo , Útero/patología
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