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1.
Small ; 18(19): e2107491, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35195340

RESUMEN

Real-time observation of the electrochemical mechanistic behavior at various scales offers new insightful information to improve the performance of lithium-ion batteries (LIBs). As complementary to the X-ray-based techniques and electron microscopy-based methodologies, neutron scattering provides additional and unique advantages in materials research, owing to the different interactions with atomic nuclei. The non-Z-dependent elemental contrast, in addition to the high penetration ability and weak interaction with matters, makes neutron scattering an advanced probing tool for the in operando mechanistic studies of LIBs. The neutron-based techniques, such as neutron powder diffraction, small-angle neutron scattering, neutron reflectometry, and neutron imaging, have their distinct functionalities and characteristics regimes. These result in their scopes of application distributed in different battery components and covering the full spectrum of all aspects of LIBs. The review surveys the state-of-the-art developments of real-time investigation of the dynamic evolutions of electrochemically active compounds at various scales using neutron techniques. The atomic-scale, the mesoscopic-scale, and at the macroscopic-scale within LIBs during electrochemical functioning provide insightful information to battery researchers. The authors envision that this review will popularize the applications of neutron-based techniques in LIB studies and furnish important inspirations to battery researchers for the rational design of the new generation of LIBs.

2.
Phys Chem Chem Phys ; 22(21): 11984-11995, 2020 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-32420565

RESUMEN

Structural evolution, electrical conductivity, oxygen nonstoichiometry and oxygen transport properties of perovskite-type oxides La0.6A0.4FeO3-δ (A = Ca, Sr, and Ba) were investigated. La0.6Ca0.4FeO3-δ (LCF64) and La0.6Sr0.4FeO3-δ (LSF64) show a phase transformation in air at elevated temperature, i.e., from orthorhombic (Pnma) to rhombohedral (R3[combining macron]c) and from rhombohedral to cubic (Pm3[combining macron]m), respectively, while La0.6Ba0.4FeO3-δ (LBF64) remains cubic over the entire temperature range from room temperature to 1000 °C. The different phase behaviour of the solids is interpreted to reflect the decreased tendency for octahedral tilting with increasing alkaline-earth-metal dopant ion radius. The electrical conductivity of LSF64 is 191 S cm-1 in air at 800 °C, decreasing to a value of 114 S cm-1 at a pO2 of 0.01 atm, and found over this pO2 range roughly twice as high as those of LCF64 and LBF64. Failure to describe the data of electrical conductivity using Holstein's small polaron theory is briefly discussed. Chemical diffusion coefficients and surface exchange coefficients of the materials in the range 650-900 °C were extracted from data of electrical conductivity relaxation. Data of oxygen nonstoichiometry was used to calculate the vacancy diffusion coefficients from the measured chemical diffusion coefficients. The calculated migration enthalpies are found to decrease in the order LCF64 (1.08 ± 0.04 eV) > LSF64 (0.95 ± 0.01 eV) > LBF64 (0.81 ± 0.01 eV). The estimated ionic conductivities of the materials, at 900 °C, are within a factor of 1.4.

3.
Sensors (Basel) ; 20(11)2020 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-32486465

RESUMEN

A method to measure the superficial velocity of the water phase in gas-water flow using an electromagnetic flowmeter (EMF) and rotating electric field conductance sensors (REFCSs) is introduced in this paper. An electromagnetic flowmeter instrument factor model is built and the correlation between electromagnetic flowmeter output and gas holdup in different flow patterns are explored through vertical upward gas-water flow dynamic experiments in a pipe with an inner diameter (ID) of 20 mm. Water superficial velocity is predicted based on pattern identification among bubble, churn, and slug flows. The experimental results show that water superficial velocity can be predicted fairly accurately for bubble, churn, and slug flows with a water cut higher than 60% (absolute average percentage deviation and absolute average deviation are 4.1057% and 0.0281 m/s, respectively). The output of the electromagnetic flowmeter is unstable and invalid in slug flows with a water cut below 60% due to the non-conducting gas slug is almost filling the pipe. Therefore, the electromagnetic flowmeter is not preferred to be used in such conditions.

4.
Molecules ; 25(16)2020 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-32781605

RESUMEN

Simonsinol is a natural sesqui-neolignan firstly isolated from the bark of Illicium simonsii. In this study, the anti-inflammatory activity of simonsinol was investigated with a lipopolysaccharide (LPS)-stimulated murine macrophages RAW264.7 cells model. The results demonstrated that simonsinol could antagonize the effect of LPS on morphological changes of RAW264.7 cells, and decrease the production of nitric oxide (NO), tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) in LPS-stimulated RAW264.7 cells, as determined by Griess assay and enzyme-linked immunosorbent assay (ELISA). Furthermore, simonsinol could downregulate transcription of inducible nitric oxide synthase (iNOS), TNF-α, and IL-6 as measured by reverse transcription polymerase chain reaction (RT-PCR), and inhibit phosphorylation of the alpha inhibitor of NF-κB (IκBα) as assayed by Western blot. In conclusion, these data demonstrate that simonsinol could inhibit inflammation response in LPS-stimulated RAW264.7 cells through the inactivation of the nuclear transcription factor kappa-B (NF-κB) signaling pathway.


Asunto(s)
Antiinflamatorios/farmacología , Lignanos/farmacología , Lipopolisacáridos/farmacología , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Interleucina-6/biosíntesis , Interleucina-6/genética , Ratones , Inhibidor NF-kappaB alfa/metabolismo , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo II/genética , Fosforilación/efectos de los fármacos , Células RAW 264.7 , Transcripción Genética/efectos de los fármacos , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/genética
5.
Sensors (Basel) ; 19(12)2019 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-31213018

RESUMEN

In the process of production logging to evaluate fluid flow inside pipe, logging tools that force all flow to pass through a small measuring pipe are commonly utilized for measuring mixture density. For these logging tools, studying the fluid flow phenomenon inside the small diameter pipe and improving the prediction accuracy of pressure drop are beneficial to accurately measure mixture density. In this paper, a pressure drop prediction system is designed based on a combination of an eight-electrode rotating electric field conductance sensor (REFCS), plug-in cross-correlation conductance sensor, and differential pressure sensor. This combination overcomes the limitation of the existing pressure drop prediction model that the inlet flow velocity needs to be known. An experiment is conducted in a flow loop facility with 20 mm inner diameter small pipe. The responses of the combination sensors are collected. The REFCS is used to identify flow pattern and measure water holdup. During which five flow patterns are identified by recurrence plot method, i.e., slug flow, bubble flow, churn flow, bubble-slug transitional flow, and slug-churn transitional flow. The mixture velocity of two-phase flow is determined by the plug-in conductance sensor. The differential pressure sensor provides a differential pressure fluctuation signal. Five models of prediction of pressure drop are evaluated. The mixture friction factor of gas-water two-phase flow is obtained by a fitting method based on the measured parameters and flow pattern identification using the optimal model. Then, the pressure drop can be predicted according to the measurement results of a conductance sensor and fitting relationship. The results of pressure drop prediction show that the model proposed by Ansari et al. presents a higher accuracy compared with the other four differential pressure models with the absolute average percentage deviation (AAPD) of less than 2.632%. Moreover, the accuracy of pressure drop prediction of the Zhang et al. model is improved by using the mixture friction factor.

6.
Planta ; 243(2): 501-17, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26497871

RESUMEN

MAIN CONCLUSION : Large-scale comparative phosphoprotein analysis in maize seedlings reveals a complicated molecular regulation mechanism at the phosphoproteomic level during de-etiolation. In the present study we report a phosphoproteomic study conducted on Zea mays etiolated leaves harvested at three time points during greening (etiolated seedlings and seedlings exposed to light for 6 or 12 h). We identified a total of 2483 phosphopeptides containing 2389 unambiguous phosphosites from 1339 proteins. The abundance of nearly 692 phosphorylated peptides containing 783 phosphosites was reproducible and profiled with high confidence among treatments. Comparisons with other large-scale phosphoproteomic studies revealed that 473 of the phosphosites are novel to this study. Of the 783 phosphosites identified, 171, 79, and 138 were identified in 0, 6, and 12 h samples, respectively, which suggest that regulation of phosphorylation plays important roles during maize seedling de-etiolation. Our experimental methods included enrichment of phosphoproteins, allowing the identification of a great number of low abundance proteins, such as transcription factors, protein kinases, and photoreceptors. Most of the identified phosphoproteins were involved in gene transcription, post-transcriptional regulation, or signal transduction, and only a few were involved in photosynthesis and carbon metabolism. It is noteworthy that tyrosine phosphorylation and calcium signaling pathways might play important roles during maize seedling de-etiolation. Taken together, we have elucidated a new level of complexity in light-induced reversible protein phosphorylation during maize seedling de-etiolation.


Asunto(s)
Fosfoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Zea mays/metabolismo , Fosfoproteínas/genética , Proteínas de Plantas/genética , Proteómica , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Transducción de Señal , Zea mays/crecimiento & desarrollo
7.
Chaos ; 26(6): 063117, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27368782

RESUMEN

Exploring the dynamical behaviors of high water cut and low velocity oil-water flows remains a contemporary and challenging problem of significant importance. This challenge stimulates us to design a high-speed cycle motivation conductance sensor to capture spatial local flow information. We systematically carry out experiments and acquire the multi-channel measurements from different oil-water flow patterns. Then we develop a novel multivariate weighted recurrence network for uncovering the flow behaviors from multi-channel measurements. In particular, we exploit graph energy and weighted clustering coefficient in combination with multivariate time-frequency analysis to characterize the derived complex networks. The results indicate that the network measures are very sensitive to the flow transitions and allow uncovering local dynamical behaviors associated with water cut and flow velocity. These properties render our method particularly useful for quantitatively characterizing dynamical behaviors governing the transition and evolution of different oil-water flow patterns.

8.
Molecules ; 21(5)2016 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-27171070

RESUMEN

In this study, four new lignan glucosides, named difengpiosides A-D (1-4), were isolated from the stem barks of Illicium difengpi, together with seven known compounds 5-11. Their structures were identified on the basis of spectroscopic analyses (1D and 2D NMR, HRESIMS, CD) and a comparison with literature data. All the compounds were evaluated for their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells.


Asunto(s)
Glucósidos/química , Glucósidos/farmacología , Illicium/química , Lignanos/análisis , Óxido Nítrico/análisis , Animales , Glucósidos/aislamiento & purificación , Lipopolisacáridos/farmacología , Ratones , Estructura Molecular , Corteza de la Planta/química , Extractos Vegetales/química , Tallos de la Planta/química , Células RAW 264.7
9.
Zhongguo Zhong Yao Za Zhi ; 40(4): 686-90, 2015 Feb.
Artículo en Zh | MEDLINE | ID: mdl-26137691

RESUMEN

Fourteen compounds were isolated from 95% ethanol extract by silica gel, MCI, and ODS column chromatography. These compounds were respectively identified as quercetin (1), kaempferol (2), (+)-catechin (3), fraxin (4), protocatechuic acid (5), gallic acid (6), methyl gallate (7), ethyl gallate (8), apocynol A (9), baccatin (10), cerevisterol (11), ellagic acid (12), 3, 3',4'-tri-0-methylellagic acid(13) and N-benzoyl-L-phenylalaninyl-N-benzoyl-L-phenylalaninate(14) by analyzing their spectral data and comparing with the previously reported literatures. Except for gallic acid (6), all other compounds were isolated from this plant for the first time. Compounds 1, 2 and 6 showed moderate anti-proliferation activities on tumor cells.


Asunto(s)
Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/toxicidad , Euphorbiaceae/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Plantas Medicinales/química , Espectrometría de Masa por Ionización de Electrospray
10.
Zhongguo Zhong Yao Za Zhi ; 40(22): 4428-32, 2015 Nov.
Artículo en Zh | MEDLINE | ID: mdl-27097419

RESUMEN

Sixteen compounds have been isolated from the EtOAc fraction of 95% ethanolic extract of Sophora dunnii through silica gel, Sephadex LH-20 and semi-prerarative HPLC column chromatographies. Their structures were identified on the basis of NMR and MS spectra data as phaseollidin (1), L-maackiain (2), 2-(2',4'-dihidroxyphenyl)-5,6-methylenedioxy benzofuran (3), 8-demethyl-farrerol (4), liquiritigenin (5), genistein (6), 6-methylgenistein (7), 5-O-methyl genistein (8), 7,2',4'-trihydroxys-5-methoxy-isoflavanone (9), 7, 3', 4'-trihydroxy-isoflavanone (10), erythribyssin D (11), calycosin (12), trans-resveratrol (13), cis-resveratrol (14), stigmasterol (15), ß-sitosterol (16). Among these, compounds 1-14 and 16 were isolated from this plant for the first time.


Asunto(s)
Medicamentos Herbarios Chinos/química , Sophora/química , Fraccionamiento Químico , Medicamentos Herbarios Chinos/aislamiento & purificación , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray
11.
Fitoterapia ; 177: 106145, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39059747

RESUMEN

Five new compounds, including two sesquiterpenoid glycosides (1 and 2), two monoterpenoid glycosides (3 and 4), and a quinovose ester (5), together with four known compounds (6-9) were isolated from branches and leaves of Pittosporum pulchrum Gagnep. Their structures were established by 1D and 2D NMR, HR-ESI-MS, IR and UV spectral analyses. This is the first time to investigate the chemical constituents of P. pulchrum. Subsequently, the anti-inflammatory and antioxidant activities of different solvent fractions of ethanol extract and isolated compounds were evaluated. Dichloromethane and ethyl acetate fractions dramatically inhibited the production of NO in a concentration-dependent manner in LPS-induced RAW264.7 cells. Ethyl acetate and n-butanol fractions showed excellent DPPH radical scavenging activities with IC50 values of 24.31 µg/mL and 27.81 µg/mL, respectively. Compounds 7 and 8 might be potential natural antioxidants with IC50 values of 16.13 µM and 24.81 µM, respectively.

12.
Adv Mater ; : e2404630, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38857546

RESUMEN

The extreme fast charging performance of lithium metal batteries (LMBs) with a long life is an important focus in the development of next-generation battery technologies. The friable solid electrolyte interphase and dendritic lithium growth are major problems. The formation of an inorganic nanocrystal-dominant interphase produced by preimmersing the Li in molten lithium bis(fluorosulfonyl)imide that suppresses the overgrowth of the usual interphase is reported. Its high surface modulus combined with fast Li+ diffusivity enables a reversible dendrite-proof deposition under ultrahigh-rate conditions. It gives a record-breaking cumulative plating/stripping capacity of >240 000 mAh cm-2 at 30 mA cm-2@30 mAh cm-2 for a symmetric cell and an extreme fast charging performance at 6 C for 500 cycles for a Li||LiCoO2 full cell with a high-areal-capacity, thus expanding the use of LMBs to high-loading and power-intensive scenarios. Its usability both in roll-to-roll production and in different electrolytes indicating the scalable and industrial potential of this process for high-performance LMBs.

13.
Front Pharmacol ; 15: 1326415, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38606179

RESUMEN

Yi Mai Jian herbal formula (YMJ) is formulated with Eucommiae Folium, Astragali Radix, Ligustri Lucidi Fructus, and Elaeagnus Fructus to improve bone function in traditional Chinese medicine. The anti-osteoporotic effects of YMJ in bone metabolism were evaluated in ovariectomized (OVX) rats. The skeletal structure of the femur and vertebrae was analyzed after treating OVX rats with YMJ for 114 days. The results showed that YMJ significantly increased the bone mineral density (BMD) and trabecular number (Tb. N) of the femur and 5th lumbar vertebrae and reduced trabecular separation (Tb. Sp). Moreover, trabecular bone volume/total tissue volume (BV/TV), bone stiffness, and maximum femur load were significantly increased. The serum concentrations of NTX1 and PYD were significantly decreased. According to these results, YMJ could ameliorate osteoporosis in ovariectomized rats. Eucommiae Folium and Elaeagnus Fructus inhibited osteoclast differentiation, Ligustri Lucidi Fructus inhibited calcium reabsorption, Astragali Radix stimulated osteoblast proliferation, and Astragali Radix and Eucommiae Folium stimulated mineralization. Therefore, the combination of the four herbs into one formula, YMJ, could alleviate bone remodeling caused by low estrogen levels. We suggest that YMJ could be a healthy food candidate for preventing post-menopausal osteoporosis.

14.
Mol Biol Rep ; 40(7): 4529-42, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23677710

RESUMEN

Induction and break of bud dormancy are important features for perennial plants surviving extreme seasonal variations in climate. However, the molecular mechanism of the dormancy regulation, still remain poorly understood. To better understand the molecular basis of poplar bud dormancy, we used a label-free quantitative proteomics method based on nanoscale ultra performance liquid chromatography-ESI-MS(E) for investigation of differential protein expression during dormancy induction, dormancy, and dormancy break in apical buds of poplar (Populus simonii × P. nigra). Among these identified over 300 proteins during poplar bud dormancy, there are 74 significantly altered proteins, most of which involved in carbohydrate metabolism (22 %), redox regulation (19 %), amino acid transport and metabolism (10 %), and stress response (8 %). Thirty-one of these proteins were up-regulated, five were down-regulated during three phase, and thirty-eight were expressed specifically under different conditions. Pathway analysis suggests that there are still the presence of various physiological activities and a particular influence on photosynthesis and energy metabolism during poplar bud dormancy. Differential expression patterns were identified for key enzymes involved in major metabolic pathways such as glycolysis and the pentose phosphate pathway, thus manifesting the interplay of intricate molecular events in energy generation for new protein synthesis in the dormant buds. Furthermore, there are significant changes present in redox regulation and defense response proteins, for instance in peroxidase and ascorbate peroxidase. Overall, this study provides a better understanding of the possible regulation mechanisms during poplar bud dormancy.


Asunto(s)
Latencia en las Plantas , Proteínas de Plantas/metabolismo , Populus/metabolismo , Proteómica , Biología Computacional , Metabolismo Energético , Regulación de la Expresión Génica de las Plantas , Fotosíntesis , Proteínas de Plantas/química , Proteínas de Plantas/genética , Populus/genética , Proteómica/métodos
15.
J Ethnopharmacol ; 305: 116124, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-36587880

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Callicarpa longissima is a typical Yao ethnomedicine that has been used to treat arthritis in China. Our previous study found that the dichloromethane extract (DCME) of C. longissima showed anti-inflammatory activity in vitro. However, the anti-inflammatory mechanism and detailed chemical composition of DCME remain unclear, which lead to the original interest of this study. AIM OF THE STUDY: The study aimed to evaluate the anti-inflammatory properties of the DCME from C. longissima and further explore the accurate chemical components responsible for this active extract. MATERIALS AND METHODS: The anti-inflammatory activity of DCME in vivo was tested with carrageenan-induced mice paw edema model. Its anti-inflammatory mechanism was explored with LPS-stimulated RAW264.7 macrophages model. The compounds in DCME were isolated by repeated column chromatography and their structures were identified on the basis of nuclear magnetic resonance spectroscopy. The anti-inflammatory activities of the isolates in vitro were also tested by suppressing releases of inflammatory mediators (NO, IL-6 and TNF-α) in RAW264.7 macrophages model. In addition, the molecular docking analysis, which evaluated the potential interaction between the compounds and Toll-like receptor 4 (TLR4) and nuclear factor κB (NF-κB), was performed. RESULTS: DCME effectively alleviated the mice paw edema induced by carrageenan. In LPS-stimulated RAW264.7 cells, DCME significantly decreased the production of interleukin (IL)-6 and tumor necrosis factor α (TNF-α) via inhibiting their mRNA transcription, down-regulated the expression of TLR4 and myeloid differentiation factor 88, inhibited the phosphorylation of alpha inhibitor of NF-κB (IκBα), NF-κB p65, and degradation of IκBα. Twelve diterpenoid phenols were identified from DCME, and they not only showed different inhibitory effects on the production of NO, IL-6 and TNF-α in LPS-stimulated RAW264.7 cells, but also could bind to TLR4 and NF-κB as analyzed by molecular docking. CONCLUSIONS: Taken together, DCME from C. longissima could inhibit inflammatory response both in vitro and in vivo, which is mainly attributed to the synergistic effect of abundant diterpenoid phenols through inhibiting the TLR4/NF-κB signaling pathway, and might be a promising agent for the treatment of inflammatory diseases.


Asunto(s)
Callicarpa , Diterpenos , Animales , Ratones , FN-kappa B/metabolismo , Inhibidor NF-kappaB alfa/metabolismo , Cloruro de Metileno/efectos adversos , Interleucina-6/metabolismo , Carragenina/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Receptor Toll-Like 4/metabolismo , Lipopolisacáridos/farmacología , Simulación del Acoplamiento Molecular , Transducción de Señal , Antiinflamatorios/efectos adversos , Diterpenos/farmacología , Edema/inducido químicamente , Edema/tratamiento farmacológico
16.
Small Methods ; 7(7): e2300168, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37148175

RESUMEN

Lithium metal anode attracts great attention because of its high specific capacity and low redox potential. However, the uncontrolled dendrite growth and its infinite volume expansion during cycling are extremely detrimental to the practical application. The formation of a solid electrolyte interphase (SEI) plays a decisive role in the behavior of lithium deposition/dissolution during electrochemical processing. Clarifying the essential relationship between SEI and battery performance is a priority. Research in SEI is accelerated in recent years by the use of advanced simulation tools and characterization techniques. The chemical composition and micromorphology of SEIs with various electrolytes are analyzed to clarify the effects of SEI on the Coulombic efficiency and cycle life. In this review, the recent research progress focused on the composition and structure of SEI is summarized, and various advanced characterization techniques applied to the investigation of SEI are discussed. The comparisons of the representative experimental results and theoretical models of SEI in lithium metal batteries (LMBs) are exhibited, and the underneath mechanisms of interaction between SEI and the electrochemical properties of the cell are highlighted. This work offers new insights into the development of safe LMBs with higher energy density.

17.
Mater Horiz ; 10(12): 5859-5868, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37860875

RESUMEN

Cold drawing, a well-established processing technique in the polymer industry, was recently revisited and discovered as an efficient material structuring method to create ordered patterns in composites consisting of both cold-drawable polymers and brittle target materials. Such a high-yield and low-cost manufacturing technique enables the large-scale fabrication of micro-ribbon structures for a wide range of functional materials, including two-dimensional (2D) layered materials. Compared to the abundant phenomenological results from experiments, however, the underlying mechanisms of this technique are not fully explored. Here, supported by experimental investigation, finite element calculations, and theoretical modeling, we systematically study the effect of a capping layer on the controlled fragmentation of 2D materials deposited on polymer substrates during the cold drawing. The capping layer is found to prevent the premature fracture of the 2D thin films during elastic deformation of the substrate, when a specific requirement proposed by the theoretical model is satisfied. Controlled fragmentation is enabled in the necking stage due to the protective effect of the capping layer, which also influences the size of the resulting fragments. Flexible and stretchable electrodes based on 2D material ribbons are fabricated to demonstrate the effectiveness of the proposed roadmap. This study gives an accurate understanding of interactions between 2D materials, polymer substrates, and capping layers during cold drawing, and offers guidance for potential applications such as flexible electronics.

18.
Nanoscale ; 15(38): 15635-15642, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37721742

RESUMEN

Scintillators with high spatial resolution at a low radiation dose rate are desirable for X-ray medical imaging. A low radiation dose rate can be achieved using a sufficiently thick scintillator layer to absorb the incident X-ray energy completely, however, often at the expense of low spatial resolution due to the issue of optical crosstalk of scintillation light. Therefore, to achieve high sensitivity combined with high-resolution imaging, a thick scintillator with perfect light guiding properties is in high demand. Herein, a new strategy is developed to address this issue by embedding liquid scintillators into lead-containing fiber-optical plates (FOPs, n = 1.5) via the siphon effect. The liquid scintillator is composed of perovskite quantum dots (QDs)/2,5-diphenyloxazole (PPO) and the non-polar high-refractive index (n = 1.66) solvent α-bremnaphthalene. Benefiting from the pixelated and thickness-adjustable scintillators, the proposed CsPbBr3 QDs/PPO liquid scintillator-based X-ray detector achieves a detection limit of 79.1 µGy s-1 and a spatial resolution of 4.6 lp mm-1. In addition, it displays excellent tolerance against radiation (>34 h) and shows outstanding stability under ambient conditions (>160 h). This strategy could also be applied to other liquid scintillators (such as CsPbCl3 QDs and Mn:CsPbCl3 QDs). The combination of high sensitivity, high spatial resolution and stability, easy fabrication and maintenance, and a reusable substrate matrix makes these liquid scintillators a promising candidate for practical X-ray medical imaging applications.

19.
Nat Commun ; 13(1): 1123, 2022 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-35236854

RESUMEN

The oxygen redox reaction in lithium-rich layered oxide battery cathode materials generates extra capacity at high cell voltages (i.e., >4.5 V). However, the irreversible oxygen release causes transition metal (TM) dissolution, migration and cell voltage decay. To circumvent these issues, we introduce a strategy for tuning the Coulombic interactions in a model Li-rich positive electrode active material, i.e., Li1.2Mn0.6Ni0.2O2. In particular, we tune the Coulombic repulsive interactions to obtain an adaptable crystal structure that enables the reversible distortion of TMO6 octahedron and mitigates TM dissolution and migration. Moreover, this strategy hinders the irreversible release of oxygen and other parasitic reactions (e.g., electrolyte decomposition) commonly occurring at high voltages. When tested in non-aqueous coin cell configuration, the modified Li-rich cathode material, combined with a Li metal anode, enables a stable cell discharge capacity of about 240 mAh g-1 for 120 cycles at 50 mA g-1 and a slower voltage decay compared to the unmodified Li1.2Mn0.6Ni0.2O2.

20.
Front Pharmacol ; 13: 1026912, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36506588

RESUMEN

With the prevalence of obesity and other components of metabolic syndrome, Non-alcoholic fatty liver disease (NAFLD) has become increasingly common. In recent years, much attention has been paid to various plant sources, hoping to find a treatment for NAFLD in plants. The Livsooth authentic herbal formula (LAH, ), a botanical drug formula combined with Puerariae lobatae radix, Lonicerae japonicae flos, Hoveniae semen, and Siraitiae fructus. This study used a network pharmacology approach to predict the potential mechanisms of LAH against NAFLD. Gene Ontology (GO) and KEGG pathway enrichment analyses have identified potential biochemical and signaling pathways. Subsequently, the potential mechanism of action of LAH on NAFLD predicted by network pharmacology analysis was validated in a high-fat diet (HFD)-induced NAFLD model in C57BL/6 mice. Our results demonstrated that LAH ameliorated hepatocyte steatosis in liver tissue by activating the AMPK pathway and decreasing serum triglycerides, low-density lipoprotein, glucose, and cholesterol. Besides, LAH increased the hepatic antioxidant enzymes activities, suggested that LAH improved oxidative stress markers in HFD induced NAFLD mice. In vitro experiments confirmed that the active component of LAH, puerarin, regulates lipid accumulation through the AMPK pathway. In conclusion, our study shows that network pharmacology predictions are consistent with experimental validation. LAH can be a candidate supplement for the prevention of NAFLD.

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