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1.
J Phys Chem A ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016101

RESUMO

Metal-free organic dyes are promising dyes that can be applied widely in dye-sensitized solar cells (DSSCs). The rational design and selection of dyes with complementary absorption can promote the development of methods that can enhance the utilization of incident light by DSSCs, such as cosensitization and tandem devices. Based on these opinions, the structure of the reported high-performance metal-free organic dye ZL003 is used as a template to design two new metal-free organic dyes, HX-1 and HX-2, by replacing its donor unit with a 2-phenothiazine-phenylamine unit and fusing its three independent π-bridge units into a whole with the aim of driving the red shift and the blue shift of the absorption spectra of ZL003, respectively. Through theoretical investigation, it is demonstrated that the perfect complementary optical absorption of HX-1 and HX-2 can be realized as the shift of the absorption spectra of ZL003 to different directions, which means their feasibility to the application in cosensitization or tandem dye-sensitized solar cells (T-DSSCs). Furthermore, it is hypothesized that HX-1 may be the dye with better photovoltaic performance than ZL003 by modeling their intramolecular charge-transfer (ICT) processes, TiO2 surface adsorption, and photovoltaic parameters. The short-circuit current density (Jsc) and photoelectric conversion efficiency (PCE) of HX-1 are 23.10 mA·cm-2 and 21.26% in theory, compared to those of 20.68 mA·cm-2 and 19.64% in ZL003 at the same computational level, respectively. In view of the complementary optical properties, the combination of HX-1 with HX-2 may be a reasonable option for dyes for the development of a highly efficient cosensitization system or T-DSSCs in the future. In terms of such findings, these two novel metal-free organic dyes may have bright prospects in the research of highly efficient DSSCs, and this work can provide a reference for the design of dyes with complementary absorption through simple structural adjustments of the realistic dyes with high photovoltaic performance.

2.
J Surg Oncol ; 124(1): 59-66, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33765331

RESUMO

BACKGROUND: Growing evidence indicates that systemic immune inflammation index (SII) can predict the prognosis of various solid tumors. The objective of this study aimed to investigate the efficacy of SII in predicting the prognosis of gallbladder carcinoma (GBC) patients after radical surgery. METHODS: A consecutive series of 93 patients with GBC who underwent radical resection were enrolled in the retrospective study. The cutoff value for the SII was calculated using the time-dependent receiver operating characteristic (ROC) curve analysis by overall survival (OS) prediction. The associations between the SII and the clinicopathologic characteristics were analyzed using Pearson's χ2 test and Fisher's exact test. Survival curves were calculated using the Kaplan-Meier method. Univariate analysis was performed to evaluate the prognostic relevance of preoperative parameters. The multivariate Cox regression proportional hazard model was used to assess variables significant on univariate analysis. RESULTS: The Kaplan-Meier survival analysis and the multivariate analysis of patients with GBC who received radical resection showed SII independently predicted OS. The univariate analysis showed that the TNM stage, SII, CA19-9, ALP, prealbumin, NLR, MLR, lymph node metastasis, and histopathological type were all associated with overall survival. In time-dependent ROC analysis, the area of the SII-CA19-9 under the ROC curve (AUC) was higher than that of the preoperative SII or CA19-9 levels for the prediction of OS. CONCLUSION: Our results demonstrate that high SII was a predictor of poor long-term outcomes among patients with GBC undergoing curative surgery. SII-CA19-9 classification may be more effective in predicting the postoperative prognosis of GBC patients.


Assuntos
Biomarcadores Tumorais/análise , Plaquetas/patologia , Colecistectomia/mortalidade , Neoplasias da Vesícula Biliar/mortalidade , Mediadores da Inflamação/análise , Linfócitos/patologia , Neutrófilos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Neoplasias da Vesícula Biliar/imunologia , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
3.
Neurochem Res ; 44(7): 1755-1763, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31093903

RESUMO

Overexpression of extracellular signal-regulated kinase ½ (ERK ½) signaling pathway leads to overproduction of reactive oxygen species (ROS) which induces oxidative stress. Coenzyme Q10 (CoQ10) scavenges ROS and protects cells against oxidative stress. The present study was designed to examine whether the protection of Coenzyme Q10 against oxidative damage in astrocytes is through regulating ERK 1/2 pathway. Ultraviolet B (UVB) irradiation was chosen as a tool to induce oxidative stress. Murine astrocytes were treated with 10 µg/ml and 25 µg/ml of CoQ10 for 24 h prior to UVB and maintained during UVB and 24 h post-UVB. Cell viability was evaluated by counting viable cells and MTT conversion assay. ROS production was measured using fluorescent probes. Levels of p-ERK 1/2, ERK 1/2, p-PKA, PKA were detected using immunocytochemistry and/or Western blotting. The results showed that UVB irradiation decreased the number of viable cells. This damaging effect was associated with accumulation of ROS and elevations of p-ERK 1/2 and p-PKA. Treatment with CoQ10 at 25 µg/ml significantly increased the number of viable cells and prevented the UVB-induced increases of ROS, p-ERK 1/2, and p-PKA. It is concluded that suppression of the PKA-ERK 1/2 signaling pathway may be one of the important mechanisms by which CoQ10 protects astrocytes from UVB-induced oxidative damage.


Assuntos
Astrócitos/efeitos dos fármacos , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Estresse Oxidativo/efeitos da radiação , Protetores contra Radiação/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ubiquinona/análogos & derivados , Animais , Astrócitos/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Succinato Desidrogenase/metabolismo , Ubiquinona/farmacologia , Raios Ultravioleta
4.
Inorg Chem ; 57(17): 10525-10532, 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30095895

RESUMO

The self-assembly of a zinc salt with the novel ligand 4,4',4″-[(1,3,5-triazine-2,4,6-triyl)tris(sulfanediyl)]tribenzoic acid generated 3D microporous metal-organic frameworks (MOFs), namely, {[Zn4(L3-)2(O2-)(H2O)2]·4EtOH} n. The frameworks with multiple Lewis basic sites exhibit easily sensitized properties. After encapsulation of the Tb3+ cation in this Zn-MOF, the as-obtained fluorescent-functionalized Tb@Zn-MOFs not only maintain distinguished chemical stabilities but also exhibit strong characteristic emissions of trivalent terbium ions. Interestingly, Tb@Zn-MOF has been chosen to be a potential highly selective and sensitive luminescent platform for the reversible detection of PO43- ions in aqueous and living cell buffer solutions with a fast response time of 10 s and a low detection limit (0.1 ppm). Strikingly, this work presents the first example of a fluorescent sensor that can quantitate PO43- in simulated biological fluids and monitor these ions in the water system in a wide range of concentrations from 10-6 to 10-3 M.


Assuntos
Técnicas de Química Analítica/instrumentação , Corantes Fluorescentes/química , Estruturas Metalorgânicas/química , Fosfatos/análise , Zinco/química , Cristalografia por Raios X , Estabilidade de Medicamentos , Íons/análise , Limite de Detecção , Medições Luminescentes , Modelos Moleculares , Fosfatos/química , Porosidade , Térbio/química
5.
J Insect Sci ; 16(1)2016.
Artigo em Inglês | MEDLINE | ID: mdl-27271970

RESUMO

Fatty acyl-CoA reductases (FARs) are key enzymes involved in fatty alcohol synthesis. Here, we cloned and characterized full-length cDNAs of two FAR genes from the cotton mealybug, Phenacoccus solenopsis. The results showed PsFAR I and PsFAR II cDNAs were 1,584 bp and 1,515 bp in length respectively. Both PsFAR I and PsFAR II were predicted to be located in the endoplasmic reticulum by Euk-mPLoc 2.0 approach. Both of them had a Rossmann folding region and a FAR_C region. Two conservative motifs were discovered in Rossmann folding region by sequence alignment including a NADPH combining motif, TGXXGG, and an active site motif, YXXXK. A phylogenetic tree made using MEGA 6.06 indicated that PsFAR I and PsFAR II were placed in two different branches. Gene expression analysis performed at different developmental stages showed that the expression of PsFar I is significantly higher than that of PsFar II in first and second instar nymphs and in male adults. Spirotetramat treatment at 125 mg/liter significantly increased the expression of PsFar I in third instar nymphs, but there was no effect in the expression of PsFar II Our results indicated these two FAR genes showed different expression patterns during insect development and after pesticide treatment, suggesting they play different roles in insect development and detoxification against pesticides.


Assuntos
Aldeído Oxirredutases/genética , Hemípteros/enzimologia , Hemípteros/genética , Proteínas de Insetos/genética , Aldeído Oxirredutases/química , Aldeído Oxirredutases/metabolismo , Sequência de Aminoácidos , Animais , Hemípteros/classificação , Hemípteros/crescimento & desenvolvimento , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Masculino , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Ninfa/metabolismo , Filogenia , Alinhamento de Sequência
6.
Biotechnol Biotechnol Equip ; 28(4): 740-746, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-26019558

RESUMO

In order to evaluate the effects of different pretreatments on microbial transformation of saponins in Dioscorea zingiberensis (DZW), various methods have been systematically studied on a large scale. Five pretreatments, including physical separation, catalytic solvent extraction, ultrasonic fermentation, complex enzymatic hydrolyzation and enzymatic saccharification, were performed on DZW. Compared with other methods, complex enzymatic hydrolyzation significantly improved the efficiency of microbial transformation. Due to the pretreatment, a diosgenin yield of 92.6%, and diosgenin accumulation of 27.3 mg/g DZW were achieved. The high efficiency of this method was attributed to the separation of 84.3% starch and 76.5% fibre from DZW in the form of a sugar. Analysis of saponins in this microbial transformation process showed that the residual rates of the intermediate products were much lower than those obtained from other pretreatments. The results demonstrate that complex enzymatic hydrolyzation is a practical and effective pretreatment method for production of diosgenin from DZW in a microbial transformation way.

7.
Nanomaterials (Basel) ; 14(2)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276747

RESUMO

A dual-band electrochromic supercapacitor device (DESCD) can be driven by an external power supply to modulate solar radiation, which is a promising energy-saving strategy and has broad application prospects in smart windows. However, traditional power supplies, such as batteries, supercapacitors, etc., usually face limited lifetimes and potential environmental issues. Hence, we propose a self-powered DESCD based on TiO2/WO3 dual-band electrochromic material and a ternary dielectric rotating triboelectric nanogenerator (TDR-TENG). The TDR-TENG can convert mechanical energy from the environment into electrical energy to obtain a high output of 840 V, 23.9 µA, and 327 nC. The as-prepared TDR-TENG can drive the TiO2/WO3 film to store energy with a high dual-band modulation amplitude of 41.6% in the visible (VIS) region and 84% in the near-infrared (NIR) region, decreasing the indoor-outdoor light-heat interaction and thereby reducing the building energy consumption. The self-powered DESCD demonstrated in this study has multiple functions of energy harvesting, energy storage, and energy saving, providing a promising strategy for the development of self-powered smart windows.

8.
Adv Mater ; : e2405459, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847443

RESUMO

Eutectic alloys (EAs) with superior fluidity are known to be the easiest to cast into high-quality ingots, making them the alloys of choice for making large-sized structural parts. However, conventional EAs (CEAs) have never reached strength-ductility combinations on par with the best in other alloy categories. Via thermomechanical processing of cast Ni-32.88wt%Fe-9.53wt%Al CEAs, a cocoon-like nano-meshed (as fine as 26 nm) network of dislocations (CNN-D) is produced via recovery annealing, through the rearrangement of cold-work-accumulated dislocations anchored by dense pre-existing nanoprecipitates. In lieu of traditional plasticity mechanisms, such as TWIP and TRIP, the CNN-D is particularly effective in eutectic lamellae with alternating phases, as it instigates nanometer-spaced planar slip bands that not only dynamically refine the microstructure but also transmit from the FCC (face-centered-cubic) layers into the otherwise brittle B2 layers. These additional mechanisms for strengthening and strain hardening sustain stable tensile flow, resulting in a striking elevation of both strength and ductility to outrank not only all previous CEAs, but also the state of the art-additively manufactured eutectic high-entropy alloys. The CNN-D thus adds a novel microstructural strategy for performance enhancement, especially for compositionally complex alloys that increasingly make use of nanoprecipitates or local chemical order.

9.
Appl Opt ; 52(12): 2841-8, 2013 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-23669696

RESUMO

Based on the stationary random properties of remote sensing images, a correlation model is proposed to resolve the effects of the image rotation and translation on the correlation value in scene matching. The rotation invariance is achieved by measuring the image rotation with the model and compensating the rotation before the 2D translation scene matching. The input image is rotated from -5° to 5° at an interval of 1° and 11 new images are generated. The 11 new images correlate with all the template images and eleven correlation matrices are obtained. The maximum values of each correlation matrix are picked up and they could follow a fixed curve predicted by the model. Fitting the curve, the rotation corresponding to the estimated peak of the curve is considered to be the rotation of the input image. The rotation measurement of the input image can be as accurate as 0.05°. With an extra 36 rotations of the input image, the measuring range of rotation can be enlarged into ±180°. This method could be very fast and accurate for scene matching in the parallel multichannel holographic optical correlator.

10.
Micromachines (Basel) ; 14(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37374772

RESUMO

MEMS suspended inductors are susceptible to deformation under external forces, which can lead to the degradation of their electrical properties. The mechanical response of the inductor to a shock load is usually solved by a numerical method, such as the finite element method (FEM). In this paper, the transfer matrix method of linear multibody system (MSTMM) is used to solve the problem. The natural frequencies and mode shapes of the system are obtained first, then the dynamic response by modal superposition. The time and position of the maximum displacement response and the maximum Von Mises stress are determined theoretically and independently of the shock. Furthermore, the effects of shock amplitude and frequency on the response are discussed. These MSTMM results agree well with those determined using the FEM. We achieved an accurate analysis of the mechanical behaviors of the MEMS inductor under shock load.

11.
Micromachines (Basel) ; 14(10)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37893329

RESUMO

A shape adjustment method for subreflectors based on minimizing the residual wavefront error of the large dual-reflector antenna is presented. This method is used to compensate for the antenna structural deformation caused by environment loading. The shape of the subreflector is adjusted using actuators fixed under the panels. The shape adjustment response function for the subreflector shape and the actuators' adjustment amount is established, which is based on the inverse distance weighting function, and then the control function of the subreflector shape is obtained. The actuators' adjustment amount can be calculated using the least squares matrix transformation with the minimum residual wavefront error. Analysis of the experiment's results shows the residual wavefront error and primary aberration are greatly reduced under different elevation angles, and the effectiveness of the proposed method is verified.

12.
Appl Opt ; 51(10): 1558-65, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22505075

RESUMO

A volume holographic correlator is capable of inner product calculations between the input image and multiple stored images in parallel. The inner product that is the center value of the correlation can provide a scalar measure of change between two images. The inner product values are directly acquired by measuring the intensities of the correlation peaks on the CCD. However, the measured intensities are not exactly equal to the theoretical inner product values due to the redundancy correlation. The structure of the correlation peak for randomly interleaved images is analyzed. It can be regarded as two volumes, one pyramid and one prism. The relative inner product value is only determined by the height of the pyramid. The prism, caused by the redundancy correlation, appears as the background noise, which is the main source of the inner product calculation error. A calibration method is proposed to remove the prism from the measured intensity. Based on the geometric structure of the correlation peak, the theoretical expression of the inner product value for the pyramid is derived. A white image is employed as the input image and the measured correlation peak intensity is used to calibrate the inner product value. The calibration method can effectively eliminate the error caused by the redundancy correlation to achieve a high output accuracy of the volume holographic correlator. Experiments are demonstrated for the validity of the method.

13.
ACS Appl Mater Interfaces ; 14(4): 5932-5939, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35041373

RESUMO

Solid polymer electrolytes (SPEs) are promising for solid-state lithium batteries, but their practical application is significantly impeded by their low ionic conductivity and poor compatibility. Here, we report an ultrahigh elastic SPE based on cross-linked polyurethane (PU), succinonitrile (SN), and lithium bistrifluoromethanesulfonimide (LiTFSI). The resulting electrolyte (PU-SN-LiTFSI) exhibits an ionic conductivity of 2.86 × 10-4 S cm-1, a tensile strength of 3.8 MPa, and a breaking elongation exceeding 3000% at room temperature. A solid-state lithium battery using the electrolyte exhibits a high specific capacity of 150 mAh g-1 at 0.2C and a long cycling life of up to 700 cycles at 0.5C at room temperature, showing one of the best performances among its counterparts. The excellent performances are attributed to the fact that its ultrahigh elasticity, good ionic conductivity, tensile strength, and electrochemical stability contribute to robust electrode/electrolyte interfaces, thus greatly decreasing the charge-transfer resistance in charge/discharge processes. Our investigations provide a novel strategy to address the intrinsic interfacial issue of solid-state batteries.

14.
Front Psychol ; 13: 1010033, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211893

RESUMO

Science, Technology, Engineering, and Math (STEM) education emphasizes solving problems in authentic contexts and developing 21st-century skills. It also helps to cultivate individuals possessing scientific curiosity and innovative abilities. These capacities align with China's core literacy training. Recent years have seen K-12 STEM cases flourish nationally. However, little attention has been paid to the shared characteristics of these practices, and suggestions for implementing STEM in primary and secondary schools are scarce. This paper presents commonalities in STEM practices within China from a curriculum perspective and offers recommendations for implementation based on these attributes. Specifically, this study first constructed analytical metrics via the Delphi method to assess STEM cases. Next, 51 typical STEM teaching cases in different regions of China were analyzed using these metrics. Based upon the statistical results, five characteristics of STEM cases were summarized: China's STEM education has an unbalanced geographical distribution; current practices benchmark the need for innovative talent training; most instructional content is drawn from real-world problems, but interdisciplinary integration deserves closer focus; the cases featured rich teaching activities and were conducted in a project-based learning fashion with insufficient emphasis on mathematical applications; and China seems to be holistically promoting STEM education, especially through new technologies and supplementary materials. Findings should allow instructors to better understand the intricacies of STEM implementation and to promote successful STEM cases. Recommendations are also provided to optimize the localization of STEM education in China in order to cultivate innovative and interdisciplinary talent.

15.
Int Immunopharmacol ; 108: 108892, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35640376

RESUMO

BACKGROUND: As a major metabolic site, the liver is an important target organ of endotoxemia. High serum lipopolysaccharide (LPS) levels can cause hepatocyte necrosis and produce cholestasis, which results in severe liver injury. Contrastingly, thiamine (THA) has shown anti-inflammatory effects against severe infections and may be indicated for systemic endotoxemia treatment. Therefore, the present study was conducted to investigate the effective treatment of endotoxemia-induced liver injury with THA and the possible molecular mechanisms. METHODOLOGY/PRINCIPAL FINDINGS: in vivo, We established two models of endotoxemia-induced liver injury at the in vivo level using LPS and bile duct ligation (BDL) + LPS, administering prophylactic THA intraperitoneally to mice. In vitro, the effects of THA on RAW264.7 and THP-1 administration of LPS-induced inflammatory macrophage activation were observed. Metabolomic analysis screening and subsequent validation experiments were also performed. THA has different degrees of preventive therapeutic effects on different causes of endotoxemia-induced liver injury, as evidenced by a decreased alanine aminotransferase (ALT) and decreased inflammatory factors. This study aimed to clarify the specific mechanism. We subsequently found that THA reduced the inflammatory macrophages produced by RAW264.7 and THP-1 in response to LPS. Additionally, THA reduced galactose liver accumulation and improved glucose metabolism. Moreover, Galectin-3 (Gal-3), as a point of interaction between macrophage activation and galactose metabolism mechanisms, was observed to inhibit Gal-3 expression by THA at both in vivo and in vitro levels. CONCLUSIONS: This study revealed that THA may be a viable prophylactic treatment option for the prevention of liver injury occurring in endotoxemia, which is associated with its effects on the modulation of Gal-3 to improve the inflammatory response and the inhibition of galactose metabolism. Additional evidence is provided for its clinical application.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Colestase , Endotoxemia , Animais , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Colestase/complicações , Endotoxemia/tratamento farmacológico , Galactose/metabolismo , Lipopolissacarídeos/farmacologia , Fígado , Ativação de Macrófagos , Camundongos , Tiamina/metabolismo , Tiamina/farmacologia , Tiamina/uso terapêutico
16.
J Agric Food Chem ; 70(39): 12550-12564, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36154116

RESUMO

Alcoholic liver disease (ALD) is caused by alcohol abuse and can progress to hepatitis, cirrhosis, and even hepatocellular carcinoma. Previous studies suggested that Lactobacillus reuteri (L. reuteri) ameliorates ALD, but the exact mechanisms are not fully known. This study created an ALD model in mice, and the results showed L. reuteri significantly alleviating lipid accumulation in the mice. Transcriptome sequencing showed the L. reuteri treatment group had the most enriched metabolic pathway genes. We then studied the farnesoid X receptor (FXR) metabolic pathway in the mice liver tissue. Western blot analysis showed that FXR and carbohydrate response element binding protein (ChREBP) were upregulated and sterol regulatory element binding transcription factor 1 (Srebf1) and Cluster of differentiation (CD36) were downregulated in the L. reuteri-treated group. Subsequently, we administered FXR inhibitor glycine-ß-muricholic acid (Gly-ß-MCA) to mice, and the results show that Gly-ß-MCA could reduce the therapeutic effect of L. ruteri. In conclusion, our study shows L. reuteri improved liver lipid accumulation in mice via the FXR signaling regulatory axis and may be a viable treatment option for ALD.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Limosilactobacillus reuteri , Hepatopatias Alcoólicas , Animais , Carboidratos/farmacologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/patologia , Etanol/metabolismo , Glicina/farmacologia , Limosilactobacillus reuteri/genética , Lipídeos/farmacologia , Fígado/metabolismo , Hepatopatias Alcoólicas/metabolismo , Camundongos , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais , Esteróis/metabolismo , Transcriptoma
17.
Nanoscale ; 13(31): 13273-13284, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34259294

RESUMO

Recently, much attention has been paid to two-dimensional MOF nanosheets (MONs) due to their widespread application in many specific areas. In this work, a simple and efficient congenerous-exfoliation strategy was developed to prepare vast and uniform few-layered Ni2+@Ce-MOF (Ce-MOF: {[Ce(HPIA)(PIA)(H2O)2]·H2O}n) nanosheets with a thickness of ca. 10 nm. In the exfoliation process, the synergistic action of Ni2+ and methanol solvents under ultrasonication plays a major role in restraining the interactions between the layers. Importantly, supercapacitor applications indicate that the exfoliated Ni2+@Ce-MOF nanosheet shows a remarkable improvement in the specific capacitance (921.05%) in comparison with that of the bulk Ce-MOF sample before modification.

18.
Front Public Health ; 9: 561809, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33643984

RESUMO

Rapid urbanization and increasing urban density in China threaten residents' mental health. As a vital component of built environments, green space plays a key role in individuals' psychological well-being; however, the mediating effect of residents' satisfaction with the green space environment on the relationship between urban greening and residents' mental health in Chinese contexts has yet to be thoroughly explored. To fill this knowledge gap, this paper attempts to reveal the internal logic and mechanism underlying the linkages between green space, residents' mental health, and their satisfaction with green space in Shenzhen, China. Specifically, this paper explores the mediating role of residents' satisfaction with a green space environment using questionnaire survey data, "Quick Bird-2" high-resolution remote sensing image data, and a multilevel regression model. Our empirical findings indicate that the relative range of neighboring green spaces can directly improve residents' mental health. More importantly, the relationship between the relative scope of green space and residents' mental health is mediated by residents' satisfaction with the green space environment rather than its direct health effects. Given the influence of green space on residents' satisfaction with the environment, green space indirectly affects mental health. These findings should provide the government useful guidance for considering the spatial distribution and quantity of green space. Our results should also help residents improve their actual experiences and subjective satisfaction with the green space environment.


Assuntos
Parques Recreativos , Satisfação Pessoal , China , Humanos , Saúde Mental , Inquéritos e Questionários
19.
Rev Sci Instrum ; 92(9): 094903, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598506

RESUMO

A novel gravity-assisted automatic docking (GAAD) method is presented for the study of interdiffusion processes in liquid Al-Cu melts. A novel GAAD device was designed to be suitable in a strong static magnetic field (SSMF) with a bore size of 50 mm. Energy dispersive x-ray spectroscopy was used to quantitatively analyze the concentration profiles of diffusion capillaries. The interdiffusion coefficient (DAlCu) was measured by applying Fick's second law. The combination of SSMF and GAAD made the original diffusion interface be easily determined and not be oxidized. The melt convection was completely reduced to reach the pure diffusion state. The performance of this GAAD measurement method assisted by a SSMF was successfully verified by a diffusion experiment in an Al-Cu melt.

20.
Science ; 373(6557): 912-918, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34413235

RESUMO

In human-made malleable materials, microdamage such as cracking usually limits material lifetime. Some biological composites, such as bone, have hierarchical microstructures that tolerate cracks but cannot withstand high elongation. We demonstrate a directionally solidified eutectic high-entropy alloy (EHEA) that successfully reconciles crack tolerance and high elongation. The solidified alloy has a hierarchically organized herringbone structure that enables bionic-inspired hierarchical crack buffering. This effect guides stable, persistent crystallographic nucleation and growth of multiple microcracks in abundant poor-deformability microstructures. Hierarchical buffering by adjacent dynamic strain-hardened features helps the cracks to avoid catastrophic growth and percolation. Our self-buffering herringbone material yields an ultrahigh uniform tensile elongation (~50%), three times that of conventional nonbuffering EHEAs, without sacrificing strength.

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