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1.
Small Methods ; : e2400680, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39246206

RESUMEN

Lithium iron phosphate (LiFePO4, LFP) batteries are widely used in electric vehicles and energy storage systems due to their excellent cycling stability, affordability and safety. However, the rate performance of LFP remains limited due to its low intrinsic electronic and ionic conductivities. In this work, an ex situ flash carbon coating method is developed to enhance the interfacial properties for fast charging. A continuous, amorphous carbon layer is achieved by rapidly decomposing the precursors and depositing carbon species in a confined space within 10 s. Simultaneously, different heteroatoms can be introduced into the surface carbon matrix, which regulates the irregular growth of cathode-electrolyte interphase (CEI) and selectively facilitates the inorganic region formation. The inorganic-rich, hybrid conductive CEI not only promotes electron and ion transport but also restricts parasitic side reactions. Consequently, LFP cathodes with fluorinated carbon coatings exhibited the highest capacity of 151 mAh g-1 at 0.2 C and 96 mAh g-1 at 10 C, indicating their excellent rate capability over commercial LFP (58 mAh g-1 at 10 C). This solvent-free, versatile surface modification is shown for other electrode materials, providing an efficient platform for electrode-electrolyte interphase engineering through a surface post-treatment.

2.
ACS Nano ; 18(35): 24154-24161, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39163167

RESUMEN

Fiber-shaped electrochemical capacitors (FSECs) have garnered substantial attention to emerging portable, flexible, and wearable electronic devices. However, achieving high electronic and ionic conductivity in fiber electrodes while maintaining a large specific surface area is still a challenge for enhancing the capacitance and rapid response of FSECs. Here, we present an electric-field-assisted cold-wall plasma-enhanced chemical vapor (EFCW-PECVD) method for direct growth of vertical graphene (VG) on fiber electrodes, which is incorporated in the FSECs. The customized reactor mainly consists of two radio frequency coils: one for plasma generation and the other for substrate heating. Precise temperature control can be achieved by adjusting the conductive plates and the applied power. With induction heating, only the substrate is heated to above 500 °C within just 5 min, maintaining a low temperature in the gas phase for the growth of VG with a high quality. Using this method, VG was easily grown on metallic fibers. The VG-coated titanium fibers for FSECs exhibit an ultrahigh rate performance and quick ion transport, enabling the conversion of an alternating current signal to a direct current signal and demonstrating outstanding filtering capabilities.

3.
Nat Commun ; 15(1): 6117, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39033169

RESUMEN

Per- and polyfluoroalkyl substances (PFAS) are persistent and bioaccumulative pollutants that can easily accumulate in soil, posing a threat to environment and human health. Current PFAS degradation processes often suffer from low efficiency, high energy and water consumption, or lack of generality. Here, we develop a rapid electrothermal mineralization (REM) process to remediate PFAS-contaminated soil. With environmentally compatible biochar as the conductive additive, the soil temperature increases to >1000 °C within seconds by current pulse input, converting PFAS to calcium fluoride with inherent calcium compounds in soil. This process is applicable for remediating various PFAS contaminants in soil, with high removal efficiencies ( >99%) and mineralization ratios ( >90%). While retaining soil particle size, composition, water infiltration rate, and cation exchange capacity, REM facilitates an increase of exchangeable nutrient supply and arthropod survival in soil, rendering it superior to the time-consuming calcination approach that severely degrades soil properties. REM is scaled up to remediate soil at two kilograms per batch and promising for large-scale, on-site soil remediation. Life-cycle assessment and techno-economic analysis demonstrate REM as an environmentally friendly and economic process, with a significant reduction of energy consumption, greenhouse gas emission, water consumption, and operation cost, when compared to existing soil remediation practices.

4.
Science ; 384(6702): 1318-1323, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38900888

RESUMEN

High dynamic strength is of fundamental importance for fibrous materials that are used in high-strain rate environments. Carbon nanotube fibers are one of the most promising candidates. Using a strategy to optimize hierarchical structures, we fabricated carbon nanotube fibers with a dynamic strength of 14 gigapascals (GPa) and excellent energy absorption. The dynamic performance of the fibers is attributed to the simultaneous breakage of individual nanotubes and delocalization of impact energy that occurs during the high-strain rate loading process; these behaviors are due to improvements in interfacial interactions, nanotube alignment, and densification therein. This work presents an effective strategy to utilize the strength of individual carbon nanotubes at the macroscale and provides fresh mechanism insights.

5.
J Am Chem Soc ; 146(23): 16010-16019, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38805019

RESUMEN

Flash Joule heating has emerged as an ultrafast, scalable, and versatile synthesis method for nanomaterials, such as graphene. Here, we experimentally and theoretically deconvolute the contributions of thermal and electrical processes to the synthesis of graphene by flash Joule heating. While traditional methods of graphene synthesis involve purely chemical or thermal driving forces, our results show that the presence of charge and the resulting electric field in a graphene precursor catalyze the formation of graphene. Furthermore, modulation of the current or the pulse width affords the ability to control the three-step phase transition of the material from amorphous carbon to turbostratic graphene and finally to ordered (AB and ABC-stacked) graphene and graphite. Finally, density functional theory simulations reveal that the presence of a charge- and current-induced electric field inside the graphene precursor facilitates phase transition by lowering the activation energy of the reaction. These results demonstrate that the passage of electrical current through a solid sample can directly drive nanocrystal nucleation in flash Joule heating, an insight that may inform future Joule heating or other electrical synthesis strategies.

6.
Nat Commun ; 15(1): 4541, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38806541

RESUMEN

In nature, structural and functional materials often form programmed three-dimensional (3D) assembly to perform daily functions, inspiring researchers to engineer multifunctional 3D structures. Despite much progress, a general method to fabricate and assemble a broad range of materials into functional 3D objects remains limited. Herein, to bridge the gap, we demonstrate a freeform multimaterial assembly process (FMAP) by integrating 3D printing (fused filament fabrication (FFF), direct ink writing (DIW)) with freeform laser induction (FLI). 3D printing performs the 3D structural material assembly, while FLI fabricates the functional materials in predesigned 3D space by synergistic, programmed control. This paper showcases the versatility of FMAP in spatially fabricating various types of functional materials (metals, semiconductors) within 3D structures for applications in crossbar circuits for LED display, a strain sensor for multifunctional springs and haptic manipulators, a UV sensor, a 3D electromagnet as a magnetic encoder, capacitive sensors for human machine interface, and an integrated microfluidic reactor with a built-in Joule heater for nanomaterial synthesis. This success underscores the potential of FMAP to redefine 3D printing and FLI for programmed multimaterial assembly.

7.
Horm Metab Res ; 56(7): 498-503, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38503312

RESUMEN

Our previous study showed that elevated preoperative thyroglobulin (pre-Tg) level predicted the risk of developing radioiodine refractory in PTC patients. In the present study, we aimed to evaluate the prognostic value of pre-Tg in papillary thyroid microcarcinoma (PTMC). After a specific inclusion and exclusion criteria were applied, a total of 788 PTMCs were enrolled from Jiangyuan Hospital affiliated to Jiangsu Institute of Nuclear Medicine between Jan 2015 and Dec 2019. Among them, 107 PTMCs were treated with radioiodine therapy (RAIT) and the response to therapy was grouped as excellent response (ER), and non-excellent response (NER: indeterminate response, IDR and biochemical incomplete response, BIR). Multivariable logistic regression was used to identify predictors for the response of RAIT in PTMCs. Higher pre-Tg levels were detected in PTMCs with RAIT as compared with PTMCs without RAIT (p=0.0018). Higher levels of pre-Tg were also found in patients with repeated RAIT as compared with patients with single RAIT (p<0.0001). Furthermore, pre-Tg level was higher in PTMC with IDR (n=16) and much higher in BIR (n=9) as compared with patients with ER (n=82, p=0.0003) after RAIT. Multivariate analysis showed that pre-Tg level over 16.79 ng/ml [OR: 6.55 (2.10-20.39), p=0.001] was the only independent predictor for NER in PTMC with RAIT. We found that high level of pre-Tg predicted a poor RAIT outcome in PTMC. Our finding explores a prospective way in identifying high-risk PTMCs with poor response to RAIT.


Asunto(s)
Carcinoma Papilar , Radioisótopos de Yodo , Tiroglobulina , Neoplasias de la Tiroides , Humanos , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/radioterapia , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología , Radioisótopos de Yodo/uso terapéutico , Femenino , Tiroglobulina/sangre , Masculino , Persona de Mediana Edad , Adulto , Carcinoma Papilar/radioterapia , Carcinoma Papilar/sangre , Carcinoma Papilar/patología , Pronóstico , Resultado del Tratamiento , Periodo Preoperatorio , Anciano , Biomarcadores de Tumor/sangre , Estudios Retrospectivos
8.
Adv Mater ; 36(15): e2309956, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38305742

RESUMEN

Nanoscale metallic glasses offer opportunities for investigating fundamental properties of amorphous solids and technological applications in biomedicine, microengineering, and catalysis. However, their top-down fabrication is limited by bulk counterpart availability, and bottom-up synthesis remains underexplored due to strict formation conditions. Here, a kinetically controlled flash carbothermic reaction is developed, featuring ultrafast heating (>105 K s-1) and cooling rates (>104 K s-1), for synthesizing metallic glass nanoparticles within milliseconds. Nine compositional permutations of noble metals, base metals, and metalloid (M1─M2─P, M1 = Pt/Pd, M2 = Cu/Ni/Fe/Co/Sn) are synthesized with widely tunable particle sizes and substrates. Through combinatorial development, a substantially expanded composition space for nanoscale metallic glass is discovered compared to bulk counterpart, revealing that the nanosize effect enhances glass forming ability. Leveraging this, several nanoscale metallic glasses are synthesized with composition that have never, to the knowledge, been synthesized in bulk. The metallic glass nanoparticles exhibit high activity in heterogeneous catalysis, outperforming crystalline metal alloy nanoparticles.

9.
Exp Clin Endocrinol Diabetes ; 131(11): 577-582, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37922948

RESUMEN

OBJECTIVE: To assess the prognostic value of clinicopathological factors as well as BRAF and TERT promoter mutations in predicting distant metastasis in patients with papillary thyroid cancer. DESIGN: The status of BRAF and TERTp mutations were available in 1,208 thyroid cancer patients who received thyroidectomy at Jiangyuan Hospital Affiliated to Jiangsu Institute of Nuclear Medicine from January 2008 to December 2021. Based on inclusion criteria, 99 distant metastasis thyroid cancers (DM-TCs) and 1055 patients without DM (Non-DM-TCs) were retrospectively reviewed. RESULTS: After univariate and multivariate analyses, a risk model was established for DM prediction based on factors: T3/T4 stage, lymph node metastasis (LNM) number over 5, and BRAF/TERT mutations (TLBT). It was defined based on the number of TLBT factors: low risk (no risk factor, n=896), intermediate risk (1 risk factor, n=199), and high risk (≥2 risk factors, n=59). Notably, compared with patients with low and intermediate risks, patients assigned to high TLBT risk have a shorter time of DM disease-free survival. Except for gene mutation, other factors were also included in the 2015 American Thyroid Association (ATA) risk guideline. Comparing with the ATA risk category, this risk model showed a better performance in predicting DM-TCs. CONCLUSIONS: This study proposes a TLBT risk classifier consisting of T3/T4 stages, LNM (n>5), and BRAF+TERTp mutations for predicting DM-TCs. TLBT risk stratification may help clinicians make personalized treatment management and follow-up strategies.


Asunto(s)
Telomerasa , Neoplasias de la Tiroides , Humanos , Proteínas Proto-Oncogénicas B-raf/genética , Estudios Retrospectivos , Telomerasa/genética , Regiones Promotoras Genéticas/genética , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/terapia , Neoplasias de la Tiroides/patología , Mutación
10.
Nat Commun ; 14(1): 6371, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821460

RESUMEN

Soil contamination is an environmental issue due to increasing anthropogenic activities. Existing processes for soil remediation suffer from long treatment time and lack generality because of different sources, occurrences, and properties of pollutants. Here, we report a high-temperature electrothermal process for rapid, water-free remediation of multiple pollutants in soil. The temperature of contaminated soil with carbon additives ramps up to 1000 to 3000 °C as needed within seconds via pulsed direct current input, enabling the vaporization of heavy metals like Cd, Hg, Pb, Co, Ni, and Cu, and graphitization of persistent organic pollutants like polycyclic aromatic hydrocarbons. The rapid treatment retains soil mineral constituents while increases infiltration rate and exchangeable nutrient supply, leading to soil fertilization and improved germination rates. We propose strategies for upscaling and field applications. Techno-economic analysis indicates the process holds the potential for being more energy-efficient and cost-effective compared to soil washing or thermal desorption.

11.
Sci Adv ; 9(39): eadh5131, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37756404

RESUMEN

The staggering accumulation of end-of-life lithium-ion batteries (LIBs) and the growing scarcity of battery metal sources have triggered an urgent call for an effective recycling strategy. However, it is challenging to reclaim these metals with both high efficiency and low environmental footprint. We use here a pulsed dc flash Joule heating (FJH) strategy that heats the black mass, the combined anode and cathode, to >2100 kelvin within seconds, leading to ~1000-fold increase in subsequent leaching kinetics. There are high recovery yields of all the battery metals, regardless of their chemistries, using even diluted acids like 0.01 M HCl, thereby lessening the secondary waste stream. The ultrafast high temperature achieves thermal decomposition of the passivated solid electrolyte interphase and valence state reduction of the hard-to-dissolve metal compounds while mitigating diffusional loss of volatile metals. Life cycle analysis versus present recycling methods shows that FJH significantly reduces the environmental footprint of spent LIB processing while turning it into an economically attractive process.

12.
Endocr Pathol ; 34(3): 323-332, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37572175

RESUMEN

Reliable preoperative diagnosis of thyroid nodules remained challenging because of the inconclusiveness of fine-needle aspiration (FNA) cytology. In the present study, 583 formalin-fixed paraffin embedded (FFPE) thyroid nodule tissues and 161 FNA specimens were enrolled retrospectively. Then BRAF V600E, EZH1 Q571R, SPOP P94R, and ZNF148 mutations among these samples were identified using Sanger sequencing. Based on this four-gene genomic classifier, we proposed a two-step modality to diagnose thyroid nodules to differentiate benign and malignant thyroid nodules. In the FFPE group, thyroid cancers were effectively diagnosed in 37.7% (220/583) of neoplasms by the primary BRAF V600E testing, and 15.7% (57/363) of thyroid nodules could be further determined as benign by subsequent EZH1 Q571R, SPOP P94R, and ZNF148 (we called them "ESZ") mutation testing. In the FNA group, 161 BRAF wild-type specimens were classified according to The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). A total of 7 mutated samples fell within Bethesda categories III-IV, and the mutation rate of "ESZ" in Bethesda III-IV categories was 8.4%. The two-step genomic classifier could further improve thyroid nodule diagnosis, which may inform more optimal patient management.


Asunto(s)
Neoplasias de la Tiroides , Nódulo Tiroideo , Humanos , Nódulo Tiroideo/diagnóstico , Nódulo Tiroideo/genética , Nódulo Tiroideo/patología , Proteínas Proto-Oncogénicas B-raf/genética , Estudios Retrospectivos , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Mutación , Análisis Mutacional de ADN , Complejo Represivo Polycomb 2/genética , Proteínas de Unión al ADN/genética , Factores de Transcripción/genética
13.
Vaccine ; 41(38): 5648-5654, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37544826

RESUMEN

SARS-CoV-2 vaccination has been reported to be associated with the induction of thyroid disorders. To investigate the influence of SARS-CoV-2 vaccination on the disease course of patients who were undergoing treatment for Graves' disease (GD), a total of 651 consecutive GD patients who attended follow-up visits in Jiangyuan Hospital were enrolled in this retrospective study, including 443 inactivated SARS-CoV-2 vaccine recipients and 208 unvaccinated participants. The changes in serum levels of free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH) and TSH receptor antibody (TRAb) were analyzed. Crude and adjusted hazard ratios (HRs) were estimated using Cox regression models to investigate the risks in incident TRAb positivity and hyperthyroidism recurrence following vaccination. The median levels of TRAb and fT3 significantly decreased in both vaccinated and unvaccinated groups during the GD hyperthyroidism treatment. The fT4 levels of both groups were well within normal limits and presented downward trends simultaneously. Although the present study observed an increasing trend of TSH level during follow-up, significant difference was not seen in both vaccinated and unvaccinated groups. Except for newly diagnosed GD patients, vaccinated participants had significantly lower risks of incident TRAb positivity (adjusted HR = 0.22; 95%CI: 0.10-0.48, P < 0.001) after adjusted for sex, age, disease duration and MMI dose at baseline. Besides, vaccination was unlikely to serve as a risk factor for hyperthyroidism recurrence (adjusted HR = 1.20; 95%CI: 0.51-2.83, P = 0.678). Notably, newly diagnosed patients who received vaccination were just as likely to achieve remission of thyrotoxicosis as those not receiving the vaccination at any time. Our results concluded that inactivated SARS-CoV-2 vaccination would not disturb the treatment course among GD hyperthyroidism patients.


Asunto(s)
COVID-19 , Enfermedad de Graves , Hipertiroidismo , Humanos , Vacunas contra la COVID-19/uso terapéutico , SARS-CoV-2 , Estudios Retrospectivos , COVID-19/prevención & control , Enfermedad de Graves/complicaciones , Enfermedad de Graves/tratamiento farmacológico , Hipertiroidismo/complicaciones , Estudios de Cohortes , Tirotropina/uso terapéutico , Anticuerpos , Progresión de la Enfermedad
14.
Toxicol In Vitro ; 93: 105669, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37634662

RESUMEN

Thyroid cancer is one of the most common endocrine malignancies. Differentiated thyroid cancer (DTC) treatment is based on the ability of thyroid follicular cells to accumulate radioactive iodide (RAI). DTC generally has a good prognosis. However, tumor dedifferentiation or defect in certain cell death mechanism occurs in a subset of DTC patients, leading to RAI resistance. Therefore, developing novel therapeutic approaches that enhance RAI sensitivity are still warranted. We found that curcumin, an active ingredient in turmeric with anti-cancer properties, rapidly accumulated in the mitochondria of thyroid cancer cells but not normal epithelial cells. Curcumin treatment triggered mitochondrial membrane depolarization, engulfment of mitochondria within autophagosomes and a robust decrease in mitochondrial mass and proteins, indicating that curcumin selectively induced mitophagy in thyroid cancer cells. In addition, curcumin-induced mitophagic cell death and its synergistic cytotoxic effect with radioiodine could be attenuated by autophagy inhibitor, 3-methyladenine (3-MA). Interestingly, the mechanism of mitophagy-inducing potential of curcumin was its unique mitochondria-targeting property, which induced a burst of SDH activity and excessive ROS production. Our data suggest that curcumin induces mitochondrial dysfunction and triggers lethal mitophagy, which synergizes with radioiodine to kill thyroid cancer cells.


Asunto(s)
Curcumina , Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo/tratamiento farmacológico , Curcumina/farmacología , Radioisótopos de Yodo , Succinato Deshidrogenasa/metabolismo , Mitofagia , Línea Celular Tumoral , Neoplasias de la Tiroides/radioterapia , Neoplasias de la Tiroides/tratamiento farmacológico , Mitocondrias/metabolismo
15.
Pathol Res Pract ; 246: 154495, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37172523

RESUMEN

BACKGROUND: Due to dedifferentiation of tumor cells, manifested by a decreased expression of iodide-handling genes in thyrocytes, some thyroid carcinomas lose their capability for radioiodine concentration and gradually develop radioactive iodine (RAI) resistance. This work aimed to investigate the role of tumor microenvironment (TME) in the process of tumor cell dedifferentiation. MATERIALS AND METHODS: Bioinformatic analyses and subsequent immunohistochemistry (IHC) and western blot assays were performed in papillary thyroid carcinoma (PTC) and matched normal tissue. ELISA was used to assess the secretion of cytokines under the stimulation of pharmacological endoplasmic reticulum (ER) stress inducer. RESULTS: Higher levels of pro-inflammatory cytokines, interleukin 6 (IL-6) and (C-X-C motif chemokine ligand 8 (CXCL8), were found in thyroid cancer tissues compared with matched normal tissues. ER stress, induced by stressful environmental stimuli, such as nutrient deprivation and hypoxia, occurred in thyroid tumors. Classic ER stress inducers, thapsigargin (Tg) and tunicamycin (Tm), promoted the expression of IL6 and CXCL8 in thyroid cancer cells at mRNA and protein levels. Of note, rIL-6 and rCXCL8 promoted the dedifferentiation of thyroid cancer cells or even non-transformed cells in an autocrine/paracrine manner, weakening radioiodine uptake ability of thyroid cancer cells. Intriguingly, sorafenib, a multiple kinase inhibitor (MKI), could potently suppress not only ER stress-induced but also basal expressions of IL-6 and CXCL8 in thyroid cancer cells. CONCLUSIONS: The inflammatory TME could regulate cell dedifferentiation, leading to loss of thyroid-specific gene expressions, through reciprocal interaction between thyroid tumor cells and follicular cells. Our study provides a new perspective on the mechanisms of how inflammatory TME affects DTC dedifferentiation.


Asunto(s)
Neoplasias de la Tiroides , Humanos , Neoplasias de la Tiroides/patología , Radioisótopos de Yodo , Yoduros , Interleucina-6 , Microambiente Tumoral
16.
ACS Appl Mater Interfaces ; 15(4): 5701-5708, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36661854

RESUMEN

Carbon nanotubes (CNTs) are promising building blocks for the fabrication of novel fibers with structural and functional properties. However, the mechanical and electrical performances of carbon nanotube fibers (CNTFs) are far lower than the intrinsic properties of individual CNTs. Exploring methods for the controllable assembly and continuous preparation of high-performance CNTFs is still challenging. Herein, a graphene/chlorosulfonic acid-assisted wet-stretching method is developed to produce highly densified and well-aligned graphene/carbon nanotube fibers (G/CNTFs) with excellent mechanical and electrical performances. Graphene with small size and high quality can bridge the adjacent CNTs to avoid the interfacial slippage under deformation, which facilitates the formation of a robust architecture with abundant conductive pathways. Their ordered structure and enhanced interfacial interactions endow the fibers with both high strength (4.7 GPa) and high electrical conductivity (more than 2 × 106 S/m). G/CNTF-based lightweight wires show good flexibility and knittability, and the high-performance fiber heaters exhibit ultrafast electrothermal response over 1000 °C/s and a low operation voltage of 3 V. This method paves the way for optimizing the microstructures and producing high-strength and high-conductivity CNTFs, which are promising candidates for the high-value fiber-based applications.

17.
Small ; 19(10): e2207745, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36650988

RESUMEN

Vertical graphene (VG) arrays show exposed sharp edges, ultra-low electrical resistance, large surface-to-volume ratio, and low light reflectivity, thus having great potential in emerging applications, including field emission, sensing, energy storage devices, and stray light shields. Although plasma enhanced chemical vapor deposition (PECVD) is regarded as an effective approach for the synthesis of VG, it is still challenging to increase the growth rate and height of VG arrays simultaneously. Herein, a fluorobenzene and water-assisted method to rapidly grow VG arrays in an electric field-assisted PECVD system is developed. Fluorobenzene-based carbon sources are used to produce highly electronegative fluorine radicals to accelerate the decomposition of methanol and promote the growth of VG. Water is applied to produce hydroxyl radicals in order to etch amorphous carbon and accelerate the VG growth. The fastest growth rate can be up to 15.9 µm h-1 . Finally, VG arrays with a height of 144 µm are successfully synthesized at an average rate of 14.4 µm h-1 . As a kind of super black material, these VG arrays exhibit an ultra-low reflectance of 0.25%, showing great prospect in stray light shielding.

18.
Adv Sci (Weinh) ; 9(15): e2200737, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35322591

RESUMEN

With the continuous progress in electronic devices, thermal interface materials (TIMs) are urgently needed for the fabrication of integrated circuits with high reliability and performance. Graphene as a wonderful additive is often added into polymer to build composite TIMs. However, owing to the lack of a specific design of the graphene skeleton, thermal conductivity of graphene-based composite TIMs is not significantly improved. Here a chloroform-assisted method for rapid growth of vertical graphene (VG) arrays in electric field-assisted plasma enhanced chemical vapor deposition (PECVD) system is reported. Under the optimum intensity and direction of electric field and by introducing the highly electronegative chlorine into the reactor, the record growth rate of 11.5 µm h-1 is achieved and VG with a height of 100 µm is successfully synthesized. The theoretical study for the first time reveals that the introduction of chlorine accelerates the decomposition of methanol and thus promotes the VG growth in PECVD. Finally, as an excellent filler framework in polymer matrix, VG arrays are used to construct a free-standing composite TIM, which yields a high vertical thermal conductivity of 34.2 W m-1  K-1 at the graphene loading of 8.6 wt% and shows excellent cooling effect in interfacial thermal dissipation of light emitting diode.

19.
Chemistry ; 28(31): e202200237, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35297538

RESUMEN

High-frequency responsive electrochemical capacitors (ECs), which can directly convert alternating current (AC) to direct current (DC), are getting more essential for the rapid development of electronic devices. In order to satisfy the requirements of ECs with fast rate capability and appreciable capacitance density, numerous efforts have been made towards the preparation and design of the electrode material, which is a decisive factor in the performance of ECs. Carbon-related electrode materials have been widely shown to significantly increase the performance of ECs because of their light weight, high strength, and high processability. In this concept, the latest advances in the rational design and controllable fabrication of carbon-related electrode materials, including planar 2D materials, random 3D, and vertical carbon materials are summarized. Moreover, the state of the art of carbon-based ECs is discussed from the viewpoint of the structure of the electrode and performance of ECs. Finally, this concept presents integrated perspectives on the further design and preparation of carbon related ECs.

20.
J Sci Food Agric ; 102(11): 4446-4453, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-35092610

RESUMEN

BACKGROUND: The intestinal epithelium is considered the first defense protection against exogenous harmful substances, playing an indispensable role in regulating intestinal health. The protection offered by surface-layer proteins (Slps) from different Lactobacillus strains on an impaired intestinal barrier was investigated in this study. RESULTS: Four Slps pre-incubated for 6 h significantly prevented the reduced transepithelial electrical resistance value and increased paracellular permeability in tumor necrosis factor (TNF)-α-induced Caco-2 monolayers. TNF-α induced lower protein expression of occludin and zonula occludens-1, and abnormal distributions of occludin and zonula occludens-1 were ameliorated by four Slps as well. Additionally, four Slps weakened TNF-α-evoked interleukin-8 secretion and nuclear factor-κB activation. CONCLUSION: Four Slps from different strains prevent the intestinal barrier from TNF-α-induced dysfunction through blocking the nuclear factor-κB signaling pathway. © 2022 Society of Chemical Industry.


Asunto(s)
FN-kappa B , Factor de Necrosis Tumoral alfa , Células CACO-2 , Humanos , Mucosa Intestinal/metabolismo , Lactobacillus/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Ocludina/genética , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
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