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1.
ACS Omega ; 9(1): 1546-1553, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38222638

RESUMEN

We reported a new technology for transforming N-containing organic wastes (such as aniline, adiponitrile, and tar from preoxidized PAN fibers) into N-doped carbon nanotubes (N-CNTs) with nanosized iron or nickel catalysts in two consecutive reactors at 650-800 °C. Most of the reactants were converted, and N-CNTs in large amounts were produced in the first stage of the reactor, while the reactants could be completely removed in the second stage of the reactor. The doping content of N-species on CNTs easily approached 10-22 wt %, much higher than most of the earlier reported methods. The results were potentially useful for the treatment of toxic cyano-organics and the production of high-end products simultaneously.

2.
Angew Chem Int Ed Engl ; 62(47): e202308675, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37795545

RESUMEN

The mechanism for interaction and bonding of single guest molecules with active sites fundamentally determines the sorption and subsequent catalytic processes occurring in host zeolitic frameworks. However, no real-space studies on these significant issues have been reported thus far, since atomically visualizing guest molecules and recognizing single Al T-sites in zeolites remain challenging. Here, we atomically resolved single thiophene probes interacting with acid T-sites in the ZSM-5 framework to study the bonding behaviors between them. The synergy of bifurcated three-centered hydrogen bonds and van der Waals interactions can "freeze" the near-horizontal thiophene and make it stable enough to be imaged. By combining the imaging results with simulations, direct atomic observations enabled us to precisely locate the single Al T-sites in individual straight channels. Then, we statistically found that the thiophene bonding probability of the T11 site is 15 times higher than that of the T6 site. For different acid T-sites, the variation in the interaction synergy changes the inner angle of the host-guest O-H⋅⋅⋅S hydrogen bond, thereby affecting the stability of the near-horizontal thiophene and leading to considerable bonding inhomogeneities.

3.
ACS Omega ; 8(20): 17941-17947, 2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37251164

RESUMEN

With the sustainable increase of renewable energy and the maturation of heavy vehicle market, diesel consumption would face a downward trend worldwide. Herein, we have proposed a new route for hydrocracking of light cycle oil (LCO) into aromatics and gasoline and the tandem conversion of C1-C5 hydrocarbons (byproducts) into carbon nanotubes (CNTs) and H2, and by combining the simulation with Aspen Plus software and the experimental study of C2-C5 conversion, we have built a transformation network including LCO to aromatics/gasoline, C2-C5 to CNTs and H2, the conversion of CH4 into CNTs and H2, and the cycle use of H2 with pressure swing adsorption. Mass balance, energy consumption, and economic analysis were discussed as a function of varying CNT yield and CH4 conversion. 50% of H2 required for hydrocracking of LCO can be supplied by the downstream chemical vapor deposition processes. This can greatly reduce the cost of high-priced hydrogen feedstock. If the sale price of CNTs exceeds 2170 CNY per ton, the entire process would break even for a process of dealing with 520,000 t/a LCO. These results imply the great potential of this route, considering the vast demand and the current high price of CNTs.

4.
Inorg Chem ; 61(35): 13768-13774, 2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-35998355

RESUMEN

A new metal-organic framework (MOF) with tetrazole-derived triphenylamine (TPA) as the ligand, namely Mn-TPA, has been successfully prepared and thoroughly characterized via thermogravimetric analysis, IR spectroscopy, elemental analysis, UV-vis absorption, fluorescence analysis, bond valence sum calculations, and single-crystal and powder X-ray diffraction analysis. The undulating monolayer of Mn-TPA can hinder the interaction and tight stacking among analytes, which creates a bionic microenvironment for the electrochemical recognition process. Mn-TPA exhibits high specific surface area, stable film-forming capacity, excellent electrochemical activity, and good biocompatibility. Furthermore, the developed Mn-TPA-based immunosensing system exhibits an excellent limit of detection of 0.50 pg·mL-1 toward vomitoxin, which is more outstanding than that of the reported vomitoxin-sensing system. Thus, this work shows the great potential of a well-designed MOF as an easy-to-make and highly sensitive electrochemical platform for biosensing in food safety detection and other fields.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , Técnicas Biosensibles/métodos , Inspección de Alimentos , Estructuras Metalorgánicas/química , Tetrazoles
5.
Nat Commun ; 13(1): 2924, 2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35614036

RESUMEN

The acid sites of zeolite are important local structures to control the products in the chemical conversion. However, it remains a great challenge to precisely design the structures of acid sites, since there are still lack the controllable methods to generate and identify them with a high resolution. Here, we use the lattice mismatch of the intergrown zeolite to enrich the inherent Lewis acid sites (LASs) at the interface of a mortise-tenon ZSM-5 catalyst (ZSM-5-MT) with a 90° intergrowth structure. ZSM-5-MT is formed by two perpendicular blocks that are atomically resolved by integrated differential phase contrast scanning transmission electron microscopy (iDPC-STEM). It can be revealed by various methods that novel framework-associated Al (AlFR) LASs are generated in ZSM-5-MT. Combining the iDPC-STEM results with other characterizations, we demonstrate that the partial missing of O atoms at interfaces results in the formation of inherent AlFR LASs in ZSM-5-MT. As a result, the ZSM-5-MT catalyst shows a higher selectivity of propylene and butene than the single-crystal ZSM-5 in the steady conversion of methanol. These results provide an efficient strategy to design the Lewis acidity in zeolite catalysts for tailored functions via interface engineering.

6.
Biosens Bioelectron ; 200: 113925, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34979349

RESUMEN

The current COVID-19 pandemic caused by SARS-CoV-2 is raging, seriously threatening people's lives. The establishment of rapid and accurate pathogen detection technology is not only critical in this epidemic, but also a reminder that we must always be prepared for possible future outbreaks. Therefore, we developed a Palm Germ-Radar (PaGeR) device for rapid and simple detection of COVID-19 from extracted patient sample RNA by RT-LAMP. The whole procedure of rapid COVID-19 detection is based on 4 simple steps: inactivation, extraction, amplification, and detection. SARS-CoV-2 down to 1 copy/µL could be detected selectively with naked-eye. Three detection methods (colorimetric, fluorometric and lateral dipstick readout) could be performed in PaGeR instrument. By employing the PaGeR, we successfully detected SARS-CoV-2 in clinical RNA samples isolated from swab specimens. The results showed that 15 out of 17 COVID-19 patients were diagnosed as positive while all 55 normal samples were diagnosed as negative. Therefore, the developed PaGeR instrument can realize the detection of COVID-19 with easily visualized results, providing a promising instrument for rapid detection in the community as well as at home.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Humanos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Pandemias , ARN Viral/genética , Radar , Transcripción Reversa , SARS-CoV-2 , Sensibilidad y Especificidad
7.
ACS Appl Mater Interfaces ; 13(45): 53904-53914, 2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34738784

RESUMEN

The ultrafast frequency response supercapacitor is a promising candidate for alternating current line filtering. We report the fabrication of a special structured ionic liquid-based supercapacitor with an ultrafast response of only 1.5 ms. The three-dimensional aluminum (Al) foam in situ coated with carbon layer (∼500 nm) serves as the novel, highly efficient electrode-current collector. The high porosity (95%) of Al foam allows the rapid ion diffusion and the as-obtained Al/C interface with atomic-level mixing allows the fast electron transfer, two crucial factors for ultrafast response. Hence, it possesses an excellent specific mass capacitance of 68 mF g-1 at 120 Hz, as well as an ultrahigh rate of up to 3000 V s -1. The supercapacitors exhibit frequency modulation performance in the range of 20 kHz to 16 MHz. They exhibit the similar even better alternating current filtering performance, as compared to the commercial aluminum electrolytic capacitors, detected at 10 Hz, 60 Hz, 100 Hz and 1 M Hz. These results suggest that, although ILs have high viscosity and low ion mobility, the IL-based supercapacitor has a great potential to be used as a device for alternating current line filtering, as well as providing nonvolatile and nonflammability safety.

8.
ACS Appl Mater Interfaces ; 13(36): 43266-43272, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34478256

RESUMEN

Graphene/carbon nanotube (CNT)-based adsorbents were fabricated on a kilogram scale by extrusion processing (where graphene is used as the major adsorption material and CNTs make up the backbone to enhance the mechanical strength) and then mixed and bonded with poly(tetrafluoroethylene). Kilogram-scale adsorbents were used to treat the content of o-cresol in wastewater to be <1.12 mg/kg in a continuous and reversible adsorption-desorption apparatus, which could last for 99 h with a space velocity of 30 h-1 and a total wastewater capacity of 5 tons per day. Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and Raman spectroscopy all suggested that the surface properties and pore structure of the spent adsorbents remain unchanged after recycling at both low-temperature adsorption and high-temperature desorption in vacuum. These results provided an effective reversible adsorbent system for removing aromatic organics and prompted the scaled-up applications of carbon nanomaterials in the treatment of wastewater.

9.
Small ; 16(15): e1902301, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31788946

RESUMEN

The treatment of organic wastewater is of great significance. Carbon nanotube (CNT)/graphene-based nanomaterials have great potential as absorbent materials for organic wastewater treatment owing to their high specific surface area, mesoporous structure, tunable surface properties, and high chemical stability; these attributes allow them to endure harsh wastewater conditions, such as acidic, basic, and salty conditions at high concentrations or at high temperatures. Although a substantial amount of work has been reported on the performance of CNT/graphene-based nanomaterials in organic wastewater systems, engineering challenges still exist for their practical application. Herein, the adsorption mechanism of CNT- and graphene-based nanomaterials is summarized, including the adsorption mechanism of CNTs and graphene at the atomic and molecular levels, their hydrophilic and hydrophobic surface properties, and the structure-property relationship required for adsorption to occur. Second, the structural modification and recombination methods of CNT- and graphene-based adsorbents for various organic wastewater systems are introduced. Third, the engineering challenges, including the molding of macroscopically stable adsorbents, adsorption isotherm models and adsorption kinetic behaviors, and reversible adsorption performance compared to that of activated carbon (AC) are discussed. Finally, cost issues are discussed in light of scalable and practical application of these materials.

10.
Front Immunol ; 10: 975, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31130957

RESUMEN

Objective: Lupus nephritis (LN) is one of the most serious complications of systemic lupus erythematosus (SLE). Type I interferon (IFN-I) is associated with the pathogenesis of LN. Long non-coding RNAs (lncRNAs) have been implicated in the pathogenesis of SLE, however, the roles of lncRNAs in LN are still poorly understood. Here, we identified and investigated the function of LN-associated lncRNA RP11-2B6.2 in regulating IFN-I signaling pathway. Methods: RNA sequencing was used to analyze the expression of lncRNAs in kidney biopsies from LN patients and controls. Antisense oligonucleotides and CRISPRi system or overexpression plasmids and CRISPRa system were used to perform loss or gain of function experiments. In situ hybridization, imaging flow cytometry, dual-luciferase reporter assay, and ATAC sequencing were used to study the functions of lncRNA RP11-2B6.2. RT-qPCR, ELISA, and western blotting were done to detect RNA and protein levels of specific genes. Results: Elevated lncRNA RP11-2B6.2 was observed in kidney biopsies from LN patients and positively correlated with disease activity and IFN scores. Knockdown of lncRNA RP11-2B6.2 in renal cells inhibited the expression of IFN stimulated genes (ISGs), while overexpression of lncRNA RP11-2B6.2 enhanced ISG expression. Knockdown of LncRNA RP11-2B6.2 inhibited the phosphorylation of JAK1, TYK2, and STAT1 in IFN-I pathway, while promoted the chromatin accessibility and the transcription of SOCS1. Conclusion: The expression of lncRNAs is abnormal in the kidney of LN. LncRNA RP11-2B6.2 is a novel positive regulator of IFN-I pathway through epigenetic inhibition of SOCS1, which provides a new therapeutic target to alleviate over-activated IFN-I signaling in LN.


Asunto(s)
Interferón Tipo I/inmunología , Nefritis Lúpica/genética , Nefritis Lúpica/inmunología , ARN Largo no Codificante/inmunología , Adulto , Línea Celular , Femenino , Humanos , Riñón/inmunología , Masculino , Persona de Mediana Edad , ARN Largo no Codificante/genética , Transducción de Señal , Proteína 1 Supresora de la Señalización de Citocinas/genética
11.
Chem Rec ; 19(7): 1256-1262, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30251466

RESUMEN

Graphene is a hot star in materials science with various potential application aspects, including in Li-ion battery and supercapacitor. The burst of scientific papers in this area seems to validate the performance of graphene, but also arouses large dispute. Herein, we share our judgment of these trends to all, encouraging the discussion and enhancing the understanding of the structure-performance relationship of graphene.

12.
Nano Lett ; 18(2): 1253-1258, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29378142

RESUMEN

Enriching the functionality of ferroelectric materials with visible-light sensitivity and multiaxial switching capability would open up new opportunities for their applications in advanced information storage with diverse signal manipulation functions. We report experimental observations of robust intralayer ferroelectricity in two-dimensional (2D) van der Waals layered α-In2Se3 ultrathin flakes at room temperature. Distinct from other 2D and conventional ferroelectrics, In2Se3 exhibits intrinsically intercorrelated out-of-plane and in-plane polarization, where the reversal of the out-of-plane polarization by a vertical electric field also induces the rotation of the in-plane polarization. On the basis of the in-plane switchable diode effect and the narrow bandgap (∼1.3 eV) of ferroelectric In2Se3, a prototypical nonvolatile memory device, which can be manipulated both by electric field and visible light illumination, is demonstrated for advancing data storage technologies.

13.
Front Immunol ; 9: 2967, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30619325

RESUMEN

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by augmented type I interferon signaling. High-throughput technologies have identified plenty of SLE susceptibility single-nucleotide polymorphisms (SNPs) yet the exact roles of most of them are still unknown. Functional studies are principally focused on SNPs in the coding regions, with limited attention paid to the SNPs in non-coding regions. Long non-coding RNAs (lncRNAs) are important players in shaping the immune response and show relationship to autoimmune diseases. In order to reveal the role of SNPs located near SLE related lncRNAs, we performed a transcriptome profiling of SLE patients and identified linc00513 as a significantly over expressed lncRNA containing functional SLE susceptibility loci in the promoter region. The risk-associated G allele of rs205764 and A allele of rs547311 enhanced linc00513 promoter activity and related to increased expression of linc00513 in SLE. We also identified linc00513 to be a novel positive regulator of type I interferon pathway by promoting the phosphorylation of STAT1 and STAT2. Elevated linc00513 expression positively correlated with IFN score in SLE patients. Linc00513 expression was higher in active disease patients than those inactive ones. In conclusion, our data identify two functional promoter variants of linc00513 that contribute to increased level of linc00513 and confer susceptibility on SLE. The study provides new insights into the genetics of SLE and extends the role of lncRNAs in the pathogenesis of SLE.


Asunto(s)
Regulación de la Expresión Génica/inmunología , Interferón Tipo I/metabolismo , Lupus Eritematoso Sistémico/genética , ARN Largo no Codificante/metabolismo , Transducción de Señal/genética , Adulto , Femenino , Perfilación de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Interferón Tipo I/inmunología , Lupus Eritematoso Sistémico/inmunología , Masculino , Persona de Mediana Edad , Fosforilación/genética , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas/genética , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT2/metabolismo , Transducción de Señal/inmunología , Adulto Joven
14.
RSC Adv ; 8(19): 10715-10718, 2018 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-35540479

RESUMEN

Developing nanostructured adsorbents of organics is crucial for environmental protection with low energy consumption, but care needs to be taken to prevent the loss of nanomaterials because of their small size. This paper reports the fabrication of carbon nanotube (CNT)-alumina strips (CASs) with a high surface area, sufficient mesopores and strongly interacted structure. Use of CASs allowed the rapid and reversible adsorption-desorption of para-xylene, when compared to pristine powders of CNT and activated carbon. Use of CASs is promising for the practical use when packed in a scaled adsorption tower.

15.
Angew Chem Int Ed Engl ; 56(46): 14637-14641, 2017 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-28963739

RESUMEN

As the first example of a photocatalytic system for splitting water without additional cocatalysts and photosensitizers, the comparatively cost-effective Cu2 I2 -based MOF, Cu-I-bpy (bpy=4,4'-bipyridine) exhibited highly efficient photocatalytic hydrogen production (7.09 mmol g-1 h-1 ). Density functional theory (DFT) calculations established the electronic structures of Cu-I-bpy with a narrow band gap of 2.05 eV, indicating its semiconductive behavior, which is consistent with the experimental value of 2.00 eV. The proposed mechanism demonstrates that Cu2 I2 clusters of Cu-I-bpy serve as photoelectron generators to accelerate the copper(I) hydride interaction, providing redox reaction sites for hydrogen evolution. The highly stable cocatalyst-free and self-sensitized Cu-I-bpy provides new insights into the future design of cost-effective d10 -based MOFs for highly efficient and long-term solar fuels production.

16.
Huan Jing Ke Xue ; 35(5): 1781-7, 2014 May.
Artículo en Chino | MEDLINE | ID: mdl-25055666

RESUMEN

In order to study the impact of algae control mixing technology on the distribution characteristics and movement of Cyanobacteria, the floating and subsiding velocity of Cyanobacteria in Taihu Lake was measured under different conditions such as different illuminance, temperature and pressure. The Cyanobacteria showed strong propensity of floating under the illuminance from 1500 1x to 6000 1x. The Cyanobacteria particle with floating velocity of more than 0.8 cm.min-1 accounted for 58% under the illuminance of 1 500 1x. The floating velocity slowed down when the illuminance was lower than 1 500 1x or higher than 6 000 1x. In the temperature range of 8 to 25 Celsius degree, the Cyanobacteria floated and the floating velocity increased with temperature. The Cyanobacteria floated under the pressure of 0- 0. 1 MPa and the floating velocity slowed down as the pressure increased. Most Cyanobacteria were suspended in the water when the pressure reached 0. 2-0. 3 MPa and only a small part of the Cyanobacteria floated or settled. When the pressure reached 0. 4-0. 6 MPa, the Cyanobacteria notably settled and the subsiding velocity increased with the increase of pressure. The Cyanobacteria particles with subsiding velocity of more than 1.0 cm.min-1 accounted for 52.5% when the pressure was 0. 6 MPa. Gas vesicles bursted when the gas vesicles of the Cyanobacteria could not bear the external pressure. The buoyancy of the Cyanobacteria diminished until the floating force became smaller than its weight, causing the particles of the Cyanobacteria to settle. Under normal atmospheric pressure, the particle diameter was positively correlated to the floating velocity, while negatively correlated to the density. Under high pressure, the particle diameter was positively correlated to the subsiding velocity and the density.


Asunto(s)
Cianobacterias/citología , Lagos/microbiología , Movimientos del Agua , China , Presión , Temperatura
17.
J Am Chem Soc ; 136(6): 2256-9, 2014 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-24490623

RESUMEN

We report the fabrication of one-dimensional highly electroconductive mesoporous graphene nanofibers (GNFs) by a chemical vapor deposition method using MgCO3·3H2O fibers as the template. The growth of such a unique structure underwent the first in situ decomposition of MgCO3·3H2O fibers to porous MgO fibers, followed by the deposition of carbon on the MgO surface, the removal of MgO by acidic washing, and the final self-assembly of wet graphene from single to double layer in drying process. GNFs exhibited good structural stability, high surface area, mesopores in large amount, and electrical conductivity 3 times that of carbon nanotube aggregates. It, used as an electrode in a 4 V supercapacitor, exhibited high energy density in a wide range of high power density and excellent cycling stability. The short diffusion distance for ions of ionic liquids electrolyte to the surface of GNFs yielded high surface utilization efficiency and a capacitance up to 15 µF/cm(2), higher than single-walled carbon nanotubes.

18.
Chem Commun (Camb) ; 49(91): 10727-9, 2013 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-24104401

RESUMEN

Addition of a single walled carbon nanotube in ionic liquids of EMIBF4 produced a nanofluid with increased ionic conductivity. It, as the electrolyte, allowed the increase of the capacitance, energy density and cycling stability of a supercapacitor operated at 4 V.

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