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2.
Small ; 20(9): e2306819, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38152985

RESUMO

In surface-enhanced Raman spectroscopy (SERS), 2D materials are explored as substrates owing to their chemical stability and reproducibility. However, they exhibit lower enhancement factors (EFs) compared to noble metal-based SERS substrates. This study demonstrates the application of ultrathin covellite copper sulfide (CuS) as a cost-effective SERS substrate with a high EF value of 7.2 × 104 . The CuS substrate is readily synthesized by sulfurizing a Cu thin film at room temperature, exhibiting a Raman signal enhancement comparable to that of an Au noble metal substrate of similar thickness. Furthermore, computational simulations using the density functional theory are employed and time-resolved photoluminescence measurements are performed to investigate the enhancement mechanisms. The results indicate that polar covalent bonds (Cu─S) and strong interlayer interactions in the ultrathin CuS substrate increase the probability of charge transfer between the analyte molecules and the CuS surface, thereby producing enhanced SERS signals. The CuS SERS substrate demonstrates the selective detection of various dye molecules, including rhodamine 6G, methylene blue, and safranine O. Furthermore, the simplicity of CuS synthesis facilitates large-scale production of SERS substrates with high spatial uniformity, exhibiting a signal variation of less than 5% on a 4-inch wafer.

3.
Sci Adv ; 9(16): eadf4049, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37083532

RESUMO

An integrated textile electronic system is reported here, enabling a truly free form factor system via textile manufacturing integration of fiber-based electronic components. Intelligent and smart systems require freedom of form factor, unrestricted design, and unlimited scale. Initial attempts to develop conductive fibers and textile electronics failed to achieve reliable integration and performance required for industrial-scale manufacturing of technical textiles by standard weaving technologies. Here, we present a textile electronic system with functional one-dimensional devices, including fiber photodetectors (as an input device), fiber supercapacitors (as an energy storage device), fiber field-effect transistors (as an electronic driving device), and fiber quantum dot light-emitting diodes (as an output device). As a proof of concept applicable to smart homes, a textile electronic system composed of multiple functional fiber components is demonstrated, enabling luminance modulation and letter indication depending on sunlight intensity.

4.
Nano Lett ; 23(6): 2277-2286, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36913627

RESUMO

Colloidal nanocrystals (NCs) have shown remarkable promise for optoelectronics, energy harvesting, photonics, and biomedical imaging. In addition to optimizing quantum confinement, the current challenge is to obtain a better understanding of the critical processing steps and their influence on the evolution of structural motifs. Computational simulations and electron microscopy presented in this work show that nanofaceting can occur during nanocrystal synthesis from a Pb-poor environment in a polar solvent. This could explain the curved interfaces and the olivelike-shaped NCs observed experimentally when these conditions are employed. Furthermore, the wettability of the PbS NCs solid film can be further modified via stoichiometry control, which impacts the interface band bending and, therefore, processes such as multiple junction deposition and interparticle epitaxial growth. Our results suggest that nanofaceting in NCs can become an inherent advantage when used to modulate band structures beyond what is traditionally possible in bulk crystals.

5.
Artigo em Inglês | MEDLINE | ID: mdl-35816438

RESUMO

A novel Gram-stain-positive, thin rod-shaped, non-motile, aerobic and creamy-white pigmented bacterium (designated strain WJ7-1T) was isolated from activated sludge sampled in Suwon, Republic of Korea. 16S rRNA gene sequence analysis indicated that the isolate belongs to the genus Humibacter, family Microbacteriaceae, with a sequence similarity of 97.9 % to its nearest neighbour Humibacter albus KACC 20986T. Strain WJ7-1T contained menaquinone (MK)-10 (16.0 %), 11 (48.5 %) and 12 (35.5 %) as major respiratory quinones. The predominant cellular fatty acids (>15 %) were anteiso-C17 : 0, iso-C16 : 0 and anteiso-C15 : 0. The peptidoglycan of strain WJ7-1T contained the diagnostic diamino acid ornithine and 2,4-diaminobutyric acid alanine. Alanine, glutamic acid and glycine were also present in the cell wall. The characteristic whole-cell sugars present were glucose, galactose, xylose and rhamnose. The polar lipids consisted of phosphatidylglycerol, diphosphatidylglycerol, an unidentified glycolipid and two unidentified phospholipids. Strain WJ7-1T possessed ginsenoside-converting (ß-glucosidase) activity, which enabled it to transform ginsenoside protopanaxadiol-type Rb1 (one of the dominant active components of ginseng) to compound K. The genome size of strain WJ7-1T has 4.2 Mbp and the G+C content is 68.3 mol%. Average nucleotide identity, amino acid identity and digital DNA-DNA hybridization values between strain WJ7-1T and the closely related strain were 79.8, 36.1 and 23.5 %, respectively, indicating that strain WJ7-1T represents a novel species of the genus Humibacter. Strain WJ7-1T could be distinguished from the other members of the genus Humibacter by a number of chemotaxonomic and phenotypic characteristics. Based on polyphasic taxonomic analysis, strain WJ7-1T (=KACC 19729T=LMG 30802T) represents a novel species within the genus Humibacter, for which the name Humibacter ginsenosidimutans sp. nov. is proposed.


Assuntos
Actinomycetales , Ginsenosídeos , Alanina/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Esgotos , Microbiologia do Solo , Vitamina K 2/química
6.
Invest New Drugs ; 40(5): 1001-1010, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35802288

RESUMO

Preclinical models suggest anticancer activity of IM156, a novel biguanide mitochondrial protein complex 1 inhibitor of oxidative phosphorylation (OXPHOS). This first-in-human dose-escalation study enrolled patients with refractory advanced solid tumors to determine the maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D). Eligible patients received oral IM156 every other day (QOD) or daily (QD) and were assessed for safety, dose-limiting toxicities (DLTs), pharmacokinetics, and preliminary signals of efficacy. 22 patients with advanced cancers (gastric, n = 8; colorectal, n = 3; ovarian, n = 3; other, n = 8) received IM156 100 to 1,200 mg either QOD or QD. There were no DLTs. However, 1,200 mg QD was not well tolerated due to nausea; 800 mg QD was determined as the RP2D. The most frequent treatment-related AEs (TRAEs) were nausea (n = 15; 68%), diarrhea (n = 10; 46%), emesis (n = 9; 41%), fatigue (n = 4; 18%) and abdominal pain, constipation, and blood lactate increased (n = 2 each; 9%). Grade 3 nausea (n = 3; 14%) was the only grade ≥ 3 TRAE. Plasma exposures increased dose proportionally; mean Day 27 area under the curve (AUC0-24) values were higher following QD administration compared to the respective QOD regimen. Stable disease (SD), observed in 7 (32%) patients (confirmed in 2 [9%]), was the best response. To our knowledge, this is the first phase 1 study of an OXPHOS inhibitor that established a RP2D for further clinical development in cancer. Observed AEs of IM156 were manageable and SD was the best response.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/efeitos adversos , Biguanidas/uso terapêutico , Relação Dose-Resposta a Droga , Humanos , Dose Máxima Tolerável , Náusea/induzido quimicamente , Neoplasias/metabolismo , Fosforilação Oxidativa
7.
Nanomaterials (Basel) ; 12(6)2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35335733

RESUMO

Recently, lead halide perovskite nanocrystals have been considered as potential light-emitting materials because of their narrow full width at half-maximum (FWHM) and high photoluminescence quantum yield (PLQY). In addition, they have various emission spectra because the bandgap can be easily tuned by changing the size of the nanocrystals and their chemical composition. However, these perovskite materials have poor long-term stability due to their sensitivity to moisture. Thus far, various approaches have been attempted to enhance the stability of the perovskite nanocrystals. However, the required level of stability in the mass production process of perovskite nanocrystals under ambient conditions has not been secured. In this work, we developed a facile two-step ball-milling and ethanol/water-induced phase transition method to synthesize stable CsPbBr3 perovskite materials. We obtained pure CsPbBr3 perovskite solutions with stability retention of 86% for 30 days under ambient conditions. Our materials show a high PLQY of 35% in solid films, and excellent thermal stability up to 80 °C. We believe that our new synthetic method could be applicable for the mass production of light-emitting perovskite materials.

8.
Nanomaterials (Basel) ; 12(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35159747

RESUMO

In this work, we designed and prepared a hierarchically assembled 3D plasmonic metal-dielectric-metal (PMDM) hybrid nano-architecture for high-performance surface-enhanced Raman scattering (SERS) sensing. The fabrication of the PMDM hybrid nanostructure was achieved by the thermal evaporation of Au film followed by thermal dewetting and the atomic layer deposition (ALD) of the Al2O3 dielectric layer, which is crucial for creating numerous nanogaps between the core Au and the out-layered Au nanoparticles (NPs). The PMDM hybrid nanostructures exhibited strong SERS signals originating from highly enhanced electromagnetic (EM) hot spots at the 3 nm Al2O3 layer serving as the nanogap spacer, as confirmed by the finite-difference time-domain (FDTD) simulation. The PMDM SERS substrate achieved an outstanding SERS performance, including a high sensitivity (enhancement factor, EF of 1.3 × 108 and low detection limit 10-11 M) and excellent reproducibility (relative standard deviation (RSD) < 7.5%) for rhodamine 6G (R6G). This study opens a promising route for constructing multilayered plasmonic structures with abundant EM hotspots for the highly sensitive, rapid, and reproducible detection of biomolecules.

9.
Nat Commun ; 13(1): 814, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35145096

RESUMO

Smart textiles consist of discrete devices fabricated from-or incorporated onto-fibres. Despite the tremendous progress in smart textiles for lighting/display applications, a large scale approach for a smart display system with integrated multifunctional devices in traditional textile platforms has yet to be demonstrated. Here we report the realisation of a fully operational 46-inch smart textile lighting/display system consisting of RGB fibrous LEDs coupled with multifunctional fibre devices that are capable of wireless power transmission, touch sensing, photodetection, environmental/biosignal monitoring, and energy storage. The smart textile display system exhibits full freedom of form factors, including flexibility, bendability, and rollability as a vivid RGB lighting/grey-level-controlled full colour display apparatus with embedded fibre devices that are configured to provide external stimuli detection. Our systematic design and integration strategies are transformational and provide the foundation for realising highly functional smart lighting/display textiles over large area for revolutionary applications on smart homes and internet of things (IoT).

10.
J Plast Reconstr Aesthet Surg ; 75(4): 1447-1454, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34955393

RESUMO

BACKGROUND: Among the materials used for dorsal augmentation rhinoplasty (DAR), cross-linked human acellular dermal matrix (ADM) has been claimed for its low risk of infection and extrusion. The aim of this study was to compare the effectiveness of ADM in subjects undergoing primary versus revision dorsal augmentation rhinoplasties. METHODS: Using a retrospective cohort study design, the investigators enrolled a cohort set of DAR patients operated by a single surgeon during a 65-month interval. The predictor variable was the treatment group (primary or revision DAR). The main outcome variables were postoperative changes with regard to the degree of augmentation (ratio of the dorsal height [DH] and radix height [RH] to the nasal length) and patients' and surgeons' satisfaction with the aesthetic and functional results. Other study variables were grouped into the following categories: demographic, surgical, and pathological. Descriptive, uni-, and bivariate statistics were computed using P ≤ 0.05 as a cutoff value. RESULTS: The study cohort comprised 145 subjects (75.2% with primary DAR; 39.3% females) with a mean age of 30.7 ±â€¯9.4 years (range, 19-58). DAR was linked to the significant changes in DH and RH in both the treatment groups. Comparison of the two groups revealed that there was no significant difference in DH and RH between both the groups. Surgeons' and patients' satisfaction rates were comparable between the two surgery groups, neither of which experienced serious complications. Microscopic findings of the removed ADM showed abundant collagen tissue with newly formed vessels without signs of foreign body reaction. CONCLUSION: Despite significant differences in patient characteristics (age; number of osteotomy, tip plasty, and hump reduction surgeries), the results of this study suggest that ADM can be used in both primary and revision DAR, with minimal complications.


Assuntos
Derme Acelular , Rinoplastia , Adulto , Feminino , Humanos , Masculino , Nariz/cirurgia , Reoperação/métodos , Estudos Retrospectivos , Rinoplastia/métodos , Resultado do Tratamento , Adulto Jovem
11.
Nanomaterials (Basel) ; 11(11)2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34835791

RESUMO

To effectively improve the energy density and reduce the self-discharging rate of micro-supercapacitors, an advanced strategy is required. In this study, we developed a hydroquinone (HQ)-based polymer-gel electrolyte (HQ-gel) for micro-supercapacitors. The introduced HQ redox mediators (HQ-RMs) in the gel electrolyte composites underwent additional Faradaic redox reactions and synergistically increased the overall energy density of the micro-supercapacitors. Moreover, the HQ-RMs in the gel electrolyte weakened the self-discharging behavior by providing a strong binding attachment of charged ions on the porous graphitized carbon electrodes after the redox reactions. The micro-supercapacitors with HQ gel (HQ-MSCs) showed excellent energy storage performance, including a high energy volumetric capacitance of 255 mF cm-3 at a current of 1 µA, which is 2.7 times higher than the micro-supercapacitors based on bare-gel electrolyte composites without HQ-RMs (b-MSCs). The HQ-MSCs showed comparatively low self-discharging behavior with an open circuit potential drop of 37% compared to the b-MSCs with an open circuit potential drop of 60% after 2000 s. The assembled HQ-MSCs exhibited high mechanical flexibility over the applied external tensile and compressive strains. Additionally, the HQ-MSCs show the adequate circuit compatibility within series and parallel connections and the good cycling performance of capacitance retention of 95% after 3000 cycles.

12.
ACS Appl Mater Interfaces ; 13(24): 28036-28048, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34114452

RESUMO

Sulfur is a prospective material for next-generation batteries with high theoretical capacity, but its drawbacks hinder its commercialization. To overcome the low conductivity of natural sulfur and the shuttle effect of lithium polysulfide, the study proposes a novel sulfur film coated with three-dimensional nitrogen and cobalt-codoped polyhedral carbon wrapped on a multiwalled carbon nanotube sponge (3D-S@NCoCPC sponge) composite as a high-performance cathode material for rechargeable lithium-sulfur batteries. The interconnected conductive carbon network with abundant pores provides more room for the homogeneous distribution of sulfur within the composite and creates a favorable pathway for electrolyte permeability and lithium-ion diffusion. Moreover, the strong interaction between cobalt and lithium polysulfides leads to efficient suppression of the shuttle effect. In addition, the homogeneous distribution of sulfur and cobalt within the composite enhances electronic transfer for the conversion reaction of sulfur. As expected, the cathode with a high sulfur content of 77.5 wt % in the composite achieved a high initial discharge capacity of 1192 mA h g-1 and high Coulombic efficiency of 99.98% after 100 cycles at 100 mA g-1 current density. Stable performance was achieved with 92.9% capacity retention after 200 cycles at 1000 mA/g current density.

13.
Sci Rep ; 11(1): 2082, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33654158

RESUMO

Combined carbon capture and storage and CO2-enhanced oil recovery (CCS-EOR) can reconcile the demands of business with the need to mitigate the effects of climate change. To improve the performance of CCS-EOR, liquefied petroleum gas (LPG) can be co-injected with CO2, leading to a reduction in the minimum miscibility pressure. However, gas injection can cause asphaltene problems, which undermines EOR and CCS performances simultaneously. Here, we systematically examine the mechanisms of asphaltene deposition using compositional simulations during CO2-LPG-comprehensive water-alternating-gas (WAG) injection. The LPG accelerates asphaltene deposition, reducing gas mobility, and increases the performance of residual trapping by 9.2% compared with CO2 WAG. In contrast, solubility trapping performance declines by only 3.7% because of the greater reservoir pressure caused by the increased formation damage. Adding LPG enhances oil recovery by 11% and improves total CCS performance by 9.1% compared with CO2 WAG. Based on reservoir simulations performed with different LPG concentrations and WAG ratios, we confirmed that the performance improvement of CCS-EOR associated with increasing LPG and water injection reaches a plateau. An economic evaluation based on the price of LPG should be carried out to ensure practical success.

14.
J Colloid Interface Sci ; 588: 62-69, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33388587

RESUMO

Electrochemically active redox mediators have been widely investigated in energy conversion/storage system to improve overall catalytic activities and energy storing ability by inducing favorable surface redox reactions. However, the enhancement of electrochemical activity from the utilization of redox mediators (RMs) is only confirmed through theoretical computation and laboratory-scale experiment. The use of RMs for practical, wearable, and flexible applications has been scarcely researched. Herein, for the first time, a wearable fiber-based flexible energy storage system (f-FESS) with hydroquinone (HQ) composites as a catalytically active RM is introduced to demonstrate its energy-storing roles. The as-prepared f-FESS-HQ shows the superior electrochemical performance, such as the improved energy storage ability (211.16 F L-1 and 29.3 mWh L-1) and long-term cyclability with a capacitance retention of 95.1% over 5000 cycles. Furthermore, the f-FESS-HQ can well maintain its original electrochemical properties under harsh mechanical stress (bending, knotting, and weaving conditions) as well as humid conditions in water and detergent solutions. Thus, the strategical use of electrochemically active RMs can provide the advanced solution for future wearable energy storage system.

15.
Nanomaterials (Basel) ; 10(11)2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33105663

RESUMO

Capacitive deionization (CDI) based on ion electrosorption has recently emerged as a promising desalination technology due to its low energy consumption and environmental friendliness compared to conventional purification technologies. Carbon-based materials, including activated carbon (AC), carbon aerogel, carbon cloth, and carbon fiber, have been mostly used in CDI electrodes due their high surface area, electrochemical stability, and abundance. However, the low electrical conductivity and non-regular pore shape and size distribution of carbon-based electrodes limits the maximization of the salt removal performance of a CDI desalination system using such electrodes. Metal-organic frameworks (MOFs) are novel porous materials with periodic three-dimensional structures consisting of metal center and organic ligands. MOFs have received substantial attention due to their high surface area, adjustable pore size, periodical unsaturated pores of metal center, and high thermal and chemical stabilities. In this study, we have synthesized ZIF-67 using CNTs as a substrate to fully utilize the unique advantages of both MOF and nanocarbon materials. Such synthesis of ZIF-67 carbon nanostructures was confirmed by TEM, SEM, and XRD. The results showed that the 3D-connected ZIF-67 nanostructures bridging by CNTs were successfully prepared. We applied this nanostructured ZIF-67@CNT to CDI electrodes for desalination. We found that the salt removal performance was significantly enhanced by 88% for 30% ZIF-67@CNTs-included electrodes as compared with pristine AC electrodes. This increase in salt removal behavior was analyzed by electrochemical analysis such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements, and the results indicate reduced electrical impedance and enhanced electrode capacitance in the presence of ZIF-67@CNTs.

16.
Int J Syst Evol Microbiol ; 70(1): 204-210, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31596194

RESUMO

A Gram-stain-negative, rod-shaped, motile, facultatively aerobic and ivory-pigmented bacterium (designated strain LA-55T) was isolated from a river in the Republic of Korea. On the basis of 16S rRNA gene sequencing, strain LA-55T clustered with species of the genus Brevundimonas and was closely related to B revundimonas kwangchunensis KSL-102T (97.3 %), B revundimonas aurantiaca DSM 4731T (97.1 %), B revundimonas albigilva NHI-13T (97.0 %), B revundimonas balnearis FDRGB2bT (97.0 %) and Brevundimonas aveniformis DSM 17977T (97.0 %). The average nucleotide identity value between strain LA-55T and its closest-related strain was 74.1 %, indicating that strain LA-55T represents a novel species of the genus Brevundimonas. Growth occurred at 15-40 °C on Reasoner's 2A medium in the presence of 0-2 % NaCl (w/v) and at pH 6.0-8.0. The genomic DNA G+C content was 70.5 mol% and ubiquinone 10 (Q-10) was the major respiratory quinone. The major cellular fatty acids (>5 %) were C1 8 :1 ω6c and/or C1 8 :1 ω7c (summed feature 8), C16 : 0, C1 6 :1 ω6c and/or C1 6 :1 ω7c (summed feature 3) and C18 : 1 ω7c 11-methyl. The polar lipids consisted of phosphatidylglycerol, 1,2-di-O-acyl-3-O-[d-glucopyranosyl-(1→4)-α-d-glucopyranuronosyl]glycerol, 1,2-di-O-acyl-3-O-α-d-glucopyranuronosyl glycerol, unidentified aminolipid, unidentified phosphoglycolipid and unidentified lipids. Physiological and biochemical characteristics indicated that strain LA-55T represents a novel species of the genus Brevundimonas, for which the name Brevundimonas fluminis sp. nov. is proposed. The type strain is LA-55T (=KACC 19639T=LMG 30850T).


Assuntos
Caulobacteraceae/classificação , Filogenia , Rios/microbiologia , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Composição de Bases , Caulobacteraceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
17.
Int J Syst Evol Microbiol ; 70(1): 668-674, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31665097

RESUMO

A novel Gram-reaction-negative, facultative-aerobic, motile, non-spore-forming, oval-shaped and denitrifying bacterium, designated BO-81T, was isolated from sludge sampled in the Republic of Korea. This bacterium was investigated via a polyphasic approach to reveal its taxonomic position. The results of phylogenetic analysis based on 16S rRNA gene sequencing indicated that strain BO-81T belonged to the family Rhodobacteraceae and was related to the closest species Sinirhodobacter ferrireducens (98.8 % sequence similarity), 'Sinorhodobacter hungdaonensis' (98.4 %), Rhodobacter lacus (97.8 %), Sinorhodobacter populi (96.8 %) and Rhodobacter maris (96.2 %). The average nucleotide identity and DNA-DNA hybridization values between strain BO-81T and its closely related strains were 77.7-94.2 % and 20.1-55.9 %, respectively, indicating that BO-81T represents a novel species of the genus Sinirhodobacter. Growth occurred at 18-40 °C on Reasoner's 2A medium in the presence of 0-7 % NaCl (w/v) and at pH 6.0-9.0. Strain BO-81T was characterized chemotaxonomically as having ubiquinone 10 as its predominant respiratory quinone, summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c) as its major fatty acid and phosphatidylglycerol and phosphatidylethanolamine as its predominant polar lipids. The G+C content of the genomic DNA was 68.3 mol%. The results of physiological and biochemical tests allowed phenotypic differentiation of strain BO-81T from other Sinirhodobacter species with validly published names. Therefore, the isolate represented a novel species, for which the name Sinirhodobacter hankyongi sp. nov. (type strain BO-81T=KACC 19677T=LMG 30808T) is proposed.


Assuntos
Filogenia , Rhodobacteraceae/classificação , Esgotos/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Desnitrificação , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
18.
Front Chem ; 8: 619832, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33537287

RESUMO

All-solid-state batteries have gained significant attention as promising candidates to replace liquid electrolytes in lithium-ion batteries for high safety, energy storage performance, and stability under elevated temperature conditions. However, the low ionic conductivity and unsuitability of lithium metal in solid polymer electrolytes is a critical problem. To resolve this, we used a cubic garnet oxide electrolyte (Li7La3Zr2O12 - LLZO) and ionic liquid in combination with a polymer electrolyte to produce a composite electrolyte membrane. By applying a solid polymer electrolyte on symmetric stainless steel, the composite electrolyte membrane shows high ionic conductivity at elevated temperatures. The effect of LLZO in suppressing lithium dendrite growth within the composite electrolyte was confirmed through symmetric lithium stripping/plating tests under various current densities showing small polarization voltages. The full cell with lithium iron phosphate as the cathode active material achieved a highest specific capacity of 137.4 mAh g-1 and a high capacity retention of 98.47% after 100 cycles at a current density of 50 mA g-1 and a temperature of 60°C. Moreover, the specific discharge capacities were 137 and 100.8 mAh g-1 at current densities of 100 and 200 mA g-1, respectively. This research highlights the capability of solid polymer electrolytes to suppress the evolution of lithium dendrites and enhance the performance of all-solid-state batteries.

19.
ACS Nano ; 13(11): 13047-13055, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31618016

RESUMO

Two-dimensional (2D) heterostructured or alloyed monolayers composed of transition metal dichalcogenides (TMDCs) have recently emerged as promising materials with great potential for atomically thin electronic applications. However, fabrication of such artificial TMDC heterostructures with a sharp interface and a large crystal size still remains a challenge because of the difficulty in controlling various growth parameters simultaneously during the growth process. Here, a facile synthetic protocol designed for the production of the lateral TMDC heterostructured and alloyed monolayers is presented. A chemical vapor deposition approach combined with solution-processed precursor deposition makes it possible to accurately control the sequential introduction time and the supersaturation levels of the vaporized precursors and thus reliably and exclusively produces selective and heterogeneous epitaxial growth of TMDC monolayer crystals. In addition, TMDC core/shell heterostructured (MoS2/alloy, alloy/WS2) or alloyed (Mo1-xWxS2) monolayers are also easily obtained with precisely controlled growth parameters, such as sulfur introduction timing and growth temperature. These results represent a significant step toward the development of various 2D materials with interesting properties.

20.
PLoS One ; 14(8): e0221043, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31442246

RESUMO

As the traditional IC design migrates to three-dimensional integrated circuits (3D-ICs) design, new challenges need to be considered carefully to solve its reliability and yield issues. 3D-ICs using through-silicon-vias (TSVs) can have latent defects such as resistive open and bridge defects, which are caused by the thermal stress during the fabrication process. These latent defects lead to the deterioration of the electrical performance of TSVs caused by an undesired increase in the resistance-capacitance (RC) delay. For this reason, various post-bond test methodologies have been studied to improve the reliability of 3D-ICs. Cost reduction in these TSV test architectures is also currently being studied by decreasing various factors such as hardware overhead, test time, and the peak current consumption. Usually, a single test-clock-period is required to determine whether the test result contains the defective TSV. When the test result of any TSVs fails, we use another single test-clock-period to classify its defect type. In this paper, we propose a new TSV test architecture to transfer the combined test output of the test result and the specific defect type to the pad during the single test-clock-period. Our proposed test architecture also provides a reliable block-based concurrent testing to optimize the test time by dividing the die into concurrent blocks. The experimental results showed that our proposed test architecture could reduce the test time and the hardware overhead substantially by ensuring that the reasonable peak power consumption for mass production was reasonable without the test quality being adversely affected.


Assuntos
Eletrônica/métodos , Semicondutores , Silício/química , Algoritmos , Desenho de Equipamento , Processamento de Sinais Assistido por Computador
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