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1.
Inorg Chem ; 62(5): 2470-2479, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36701249

RESUMO

The state-of-the-art transition-based electrocatalysts in alkaline media generally suffer from unavoidable surface reconstruction during oxygen evolution reaction measurements, leading to the collapse and loss of the crystalline matrix. Low potential discharge offers a gentle way for surface reconstruction and thus realizes the manipulation of the real active site. Nevertheless, the absence of a fundamental understanding focus on this discharge region renders the functional phase, either the crystalline or amorphous matrix, for the controllable reconstruction still undecidable. Herein, we report a scenario to employ different crystalline matrices as electrocatalysts for discharge region reconstruction. The representative low crystalline Ni2P (LC-Ni2P) possesses a relatively weak surface structure compared with highly crystalline or amorphous Ni2P (HC-Ni2P or A-Ni2P), which contributes abundant oxygen vacancies after the discharge process. The fast discharge behavior of LC-Ni2P leads to the uniform distribution of these vacancies and thus endows the inner interface with reactant activating functionality. A high increase in current density of 36.7% is achieved at 2.32 V (vs RHE) for the LC-Ni2P electrode. The understanding of the discharge behavior in this study, on different crystalline matrices, presents insights into the establishment of controllable surface reconstruction for an effective oxygen evolution reaction.

2.
Nanotechnology ; 32(8): 085710, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33263319

RESUMO

Designing and fabricating economically viable, high active and stable electrocatalysts play an important role for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Crystal phase is the crucial factor that governs the electrochemical property and electrocatalytic reaction pathways. Here, a one-step nickel foam derived sulfidation method was presented to synthesize self-supported NiS2 and Ni3S2. The crystal phase-dependent chemical properties related to electrocatalytic behavior were evaluated by a series of advanced characterization and density functional theory calculations. Overall, the self-supported Ni3S2 shows high electrochemical activity towards both HER and OER in alkaline conditions, which afford the current density of 10 mA cm-2 with overpotentials of 245 mV for OER and 123 mV for HER, respectively. When employed the self-supported Ni3S2 as the bifunctional electrocatalysts for overall water splitting, the entire device provides the current density of 10 mA cm-2 at 1.61 V. These results indicate that the electrocatalytic properties can be exert greater improved by controlling the crystal phase, offering the prospect for advanced materials design and development.

3.
Angew Chem Int Ed Engl ; 60(36): 20042-20048, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34254417

RESUMO

The fundamental understanding of the surface reconstruction induced by the applied potential is of great significance for enhancing the oxygen evolution reaction (OER). Here, we show that a previously overlooked discharge current in the low applied potential region also leads to in situ electrochemical activation of a nitrogen-doped nickel oxyhydroxide surface. We exploit the fact that doping of heteroatoms weakens the surface structure, and hence, a weak discharge current originating from the capacitive nature of nickel oxyhydroxide has a strong structure-reforming ability to promote the formation of nitrogen and oxygen vacancies. The current density at 1.4 V (vs. Hg/HgO) can dramatically increase by as much as 31.3 % after discharge in the low applied potential region. This work provides insight into in situ enhancement of the OER and suggests that the low applied potential region must be a primary consideration in evaluating the origin of the activity of electrocatalysts.

4.
Sensors (Basel) ; 16(4): 440, 2016 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-27023557

RESUMO

In a charge-coupled device (CCD)-based fast steering mirror (FSM) tracking control system, high control bandwidth is the most effective way to enhance the closed-loop performance. However, the control system usually suffers a great deal from mechanical resonances and time delays induced by the low sampling rate of CCDs. To meet the requirements of high precision and load restriction, fiber-optic gyroscopes (FOGs) are usually used in traditional FSM tracking control systems. In recent years, the MEMS accelerometer and gyroscope are becoming smaller and lighter and their performance have improved gradually, so that they can be used in a fast steering mirror (FSM) to realize the stabilization of the line-of-sight (LOS) of the control system. Therefore, a tentative approach to implement a CCD-based FSM tracking control system, which uses MEMS accelerometers and gyroscopes as feedback components and contains an acceleration loop, a velocity loop and a position loop, is proposed. The disturbance suppression of the proposed method is the product of the error attenuation of the acceleration loop, the velocity loop and the position loop. Extensive experimental results show that the MEMS accelerometers and gyroscopes can act the similar role as the FOG with lower cost for stabilizing the LOS of the FSM tracking control system.

5.
PLoS One ; 19(4): e0300385, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38598524

RESUMO

BACKGROUND: This study is the first to analyze LGBT portrayals in a news media dataset over a decade (2010-2020). We selected Singapore as a country of interest, emblematic of a nation grappling with state-encouraged heteronormativity and a remnant colonial law against homosexuality (377A), fraught with calls for its repeal that was only enacted in 2022. Our study is interested in this period bookended by challenge and change, particularly in newspaper portrayals of LGBT narratives. Newspapers are an important source of current information and have the power to shape societal perceptions. We lay the groundwork and provide a framework to analyze news media narratives of other Commonwealth nations with colonial pasts and inherited laws criminalizing LGBT communities. OBJECTIVES: This study analyzes LGBT portrayals in a 400-million-word news media dataset over a decade (2010-2020). First, we aimed to track the volume of LGBT media coverage over time and elucidate differences in coverage of different identity markers. Second, we aimed to track sentiments on LGBT portrayals. Third, we aimed to track salient narratives circulated about LGBT stories. METHODS: The study leveraged a 400-million-word corpus from news media in Singapore, identifying the following target keywords: LGBT, Lesbian, Gay, Bisexual, Transgender, Pink Dot (a local Pride event), 377A. First, coverage volume was tracked using annual changes in keyword mentions per million, elucidating differences in coverage of different sub-groups. Second, sentiment analysis on a valence scale was conducted on LGBT collocates. Third, we distilled salient narratives about LGBT identities using thematic labelling of top-frequency collocates. RESULTS: First, overall coverage of LGBT steadily increased over the decade, though Gay identities evidenced asymmetrical coverage-outstripping 'Bisexual' keywords by seven times, 'Lesbian' by four, 'Transgender' by two. Second, sentiment scores for Pink Dot (a local pride event) were most positive; Lesbian, Gay, LGBT, Transgender were neutral; Bisexual and 377A dipped slightly negative. Third, topics differed across the four identities: uniquely, 'Lesbian' collocates related to sensationalized cinema; 'Gay' about hate crimes; 'Bisexual' about population surveys; 'Transgender' about challenges (transitioning, alienation, suicide). CONCLUSIONS: Practically, we presented a decade-long barometer of LGBT sentiments and themes on a national level, providing a framework to analyze media for more effective communication strategies-applicable to Commonwealth countries with similar inherited colonial laws. Salient repetition through media association may unwittingly frame certain issues negatively; caution is prudent in representing each sub-group adequately, rather than portraying the LGBT identity as monolithic.


Assuntos
Homossexualidade Feminina , Minorias Sexuais e de Gênero , Pessoas Transgênero , Feminino , Humanos , Bissexualidade , Comunicação
6.
Adv Mater ; 36(23): e2313461, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38532710

RESUMO

Ion migration poses a substantial challenge in perovskite transistors, exerting detrimental effects on hysteresis and operational stability. This study focuses on elucidating the influence of ion migration on the performance of tin-based perovskite field-effect transistors (FETs). It is revealed that the high background carrier density in FASnI3 FETs arises not only from the oxidation of Sn2+ but also from the migration of FA+ ions. The formation of hydrogen bonding between FA+ and F- ions efficiently inhibits ion migration, leading to a reduction in background carrier density and an improvement in the operational stability of the transistors. The strategy of hydrogen bond is extended to fluorine-substituted additives to improve device performance. The incorporation of 4-fluorophenethylammonium iodide additives into FETs significantly minimizes the shift of turn-on voltage during cyclic measurements. Notably, an effective mobility of up to 30 cm2 V-1 s-1 with an Ion/off ratio of 107 is achieved. These findings hold promising potential for advancing tin-based perovskite technology in the field of electronics.

7.
J Colloid Interface Sci ; 658: 671-677, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38134675

RESUMO

Surface reconstruction is widely existed on the surface of transition metal-based catalysts under operando oxygen evolution reaction (OER) condition. The design and optimize the reconstruction process are essential to achieve high electrochemical active surface and thus facilitate the reaction kinetics, whereas still challenge. Herein, we exploit electrolyte engineering to regulate reconstruction on the surface of Fe2O3 catalysts under operando OER conditions. The intentional added cations in electrolyte can participate the reconstruction process and realize a desirable crystalline to amorphous structure conversion, contributing abundant well-defined active sites. Spectroscopic measurements and density functional theory calculation provide insight into the underlying role of amorphous structure for electron transfer, mass transport, and intermediate adsorption. With the assistant of Co2+ cations, the enhanced current density as large as 17.9 % can be achieved at 2.32 V (vs RHE). The present results indicate the potential of electrolyte engineering for regulating the reconstruction process and provide a generalized in-situ strategy for advanced catalysts design.

8.
J Colloid Interface Sci ; 671: 441-448, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38815379

RESUMO

Alkaline water electrolysis is apreferred technology for large-scale green hydrogen production. For most active transition metal-based catalysts during anodic oxygen evolution reaction (OER), the atomic structure of the anodic catalysts' surface often undergoes reconstruction to optimize the reaction path and enhance their catalytic activity. The design and maintenance of highly active sites during this reconstruction process remain critical and challenging for most OER catalysts. In this study, we explored the effects of crystal structures in pre-catalysts on surface reconstruction at low applied potential. Through experimental observation and theoretical calculation, we found out that catalysts with specific crystal structures exhibit superior surface remodeling ability, which enables them to better adapt to the conditions of the oxygen evolution reaction and achieve efficient catalysis. The discharge process enables the formation of abundant phosphorus vacancies on the surface, which in turn affects the efficiency of the entire oxygen evolution reaction. The optimized crystal structure of the catalyst results in an increase as high as 58.5 mA/cm2 for Ni5P4, which is twice as high as that observed for Ni2P. These results provide essential theoretical foundations and technical guidance for designing more efficient catalysts for oxygen evolution reactions.

9.
J Am Geriatr Soc ; 71(9): 2726-2735, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37314013

RESUMO

BACKGROUND: Presently, most film analyses related to older adults are peculiar to American cinema. However, film industries outside the United States are influential in their own right. As ageism is a pan-cultural phenomenon, it is important to explore filmic representations of older persons globally. This study is the first to offer a portrait of how filmic portrayals of older persons differ across regions. METHODS: We leveraged a 200-million-word movie corpus comprising over 25,000 scripts from 88 countries in 11 regions. The movies span a period of nearly 90 years, from 1930 to 2018. We identified synonyms of "older adult(s)" and compiled the top descriptors that co-occurred most frequently with them. Seventeen thousand five hundred and eight descriptors were generated from 3384 movies. Using these descriptors, we calculated the valence of filmic portrayals of older adults on a scale of 1 (most negative) to 5 (most positive) in each region. RESULTS: Positive representations of older adults in movies were lacking in all 11 regions. Four regions fell into the neutral zone and the remaining seven in the negative zone. Representations of older persons were the least negative in East Asia and South Asia, and most negative in Southeast Asia as well as the Middle East and North Africa (MENA). Our topic modeling revealed that older adults were portrayed as venerable in both South and East Asia. Meanwhile, older people were associated with death in MENA. The idea that society is ill-equipped to handle an aging population was hinted at in Southeast Asia. CONCLUSIONS: As societies worldwide navigate a major demographic turning point, it is vital that filmmakers rethink portrayals of old age. In articulating the filmic narratives surrounding old age in different regions, our study lays the foundation to combat ageism on the big screen.


Assuntos
Etarismo , Filmes Cinematográficos , Humanos , Estados Unidos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Ásia Meridional
10.
Thorac Cancer ; 14(6): 544-554, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36573325

RESUMO

OBJECTIVE: The study aimed to explore the effect of circ_0008003 on the progression of non-small-cell lung cancer (NSCLC) and its underlying regulation mechanism. METHODS: Expression of hsa_circ_0008003, miRNA (miR)-548I and karyopherin subunit α 4 (KPNA4) was examined by quantitative real-time polymerase chain reaction. Cell viability and proliferation ability were detected by cell counting kit-8 assay and 5-ethynyl-2'-deoxyuridine assay, respectively. Flow cytometry was performed to monitor cell apoptosis. Western blot assay was used to evaluate the protein levels of KPNA4, Bax, and Bcl-2. Cell migration and invasion were assessed by transwell assays. The targeted relationship between miR-548I and hsa_circ_0008003 or KPNA4 was confirmed by dual-luciferase reporter and RNA immunoprecipitation assays. Furthermore, the role of hsa_circ_0008003 in vivo was investigated by xenograft assay. RESULTS: Circ_0008003 expression was increased in NSCLC tissues and cell lines. Circ_0008003 knockdown reduced cell viability, migration, invasion, angiogenesis, and caused apoptosis in NSCLC cells. Moreover, miR-548I was targeted by circ_0008003, and miR-548I knockdown reversed the influence of circ_0008003 silence on NSCLC progression. KPNA4 was targeted by miR-548I, and miR-548I overexpression suppressed cell viability, migration, invasion, angiogenesis, and promoted cell apoptosis via decreasing KPNA4. In addition, circ_0008003 regulated KPNA4 expression via miR-548I. Circ_0008003 knockdown decreased NSCLC cell growth in the xenograft model. CONCLUSION: Circular RNA hsa_circ_0008003 promoted progression in NSCLC by sponging miR-548I and regulating KPNA4 expression, hinting that circ_0008003 participates in NSCLC pathogenesis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Humanos , RNA Circular , Apoptose , Proliferação de Células , alfa Carioferinas
11.
Materials (Basel) ; 16(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36837068

RESUMO

The change in material dimensional will lead to the decline of instrument accuracy and reliability. In this paper, the characterization and analysis of the lattice constant, precipitates, and dislocation density of the material by X-ray diffraction (XRD) and transmission electron microscopy (TEM) reveals the reason why the relative dimensional change in the rolled 2024Al is one order of magnitude lower than that of the as-cast 2024Al during isothermal aging. Compared with as-cast 2024Al, the dislocation density of rolled 2024Al is higher, the lattice constant decreases less before and after aging, and the precipitates have orientation and more content, resulting in the dimensional change in rolled 2024Al being smaller than that of as-cast 2024Al. In addition, two main reasons for decreasing the dimensional change in rolled 2024Al are discussed: the decrease in lattice constant, the formation and growth of the S phase before and after aging.

12.
Materials (Basel) ; 16(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36676485

RESUMO

In this paper, two kinds of Be/2024Al composites were prepared by the pressure infiltration method using two different beryllium powders as reinforcements and 2024Al as a matrix. The effect of interfacial strength on the mechanical behavior of Be/2024Al composites was studied. Firstly, the microstructure and mechanical properties of the two composites were characterized, and then the finite element analysis (FEA) simulation was used to further illustrate the influence of interfacial strength on the mechanical properties of the two Be/2024Al composites. The mechanical tensile test results show that the tensile strength and elongation of the beryllium/2024Al composite prepared by the blocky impact grinding beryllium powder (blocky-Be/2024Al composite) are 405 MPa and 1.58%, respectively, which is superior to that of the beryllium/2024Al composite prepared by the spherical atomization beryllium powder (spherical-Be/2024Al composite), as its strength and elongation are 331 MPa and 0.38%, respectively. Meanwhile, the fracture of the former shows brittle fracture of beryllium particles and ductile fracture of aluminum, while the latter shows interface debonding. Further FEA simulation illustrates that the interfacial strength of the blocky-Be/2024Al composite is 600 MPa, which is higher than that of the spherical-Be/2024Al composite (330 MPa). Therefore, it can be concluded that the better mechanical properties of the blocky-Be/2024Al composite contribute to its stronger beryllium/aluminum interfacial strength, and the better interfacial strength might be due to the rough surface and microcrack morphology of blocky beryllium particles. These research results provide effective experimental and simulation support for the selection of beryllium powder and the design and preparation of high-performance beryllium/aluminum composites.

13.
Materials (Basel) ; 16(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37959442

RESUMO

In this paper, the effects of carbon nanotube defects and a copper surface oxide layer on a carbon nanotube-copper interface were studied via first-principles. A defect-free CNT-Cu interface, Stone-Wales defect CNT-Cu interface, single-hole and double-hole defect CNT-Cu interface, and Cu2O-Cu interface were simulated and calculated. By simulating the differential charge density, atomic population, bond population and density of states of the interface model, the effects of various defects on the interface bonding and electrical conductivity of the composites during the preparation of the CNT-reinforced copper matrix composites were analyzed, which provided theoretical guidance for the preparation of CNT/Cu composites. After that, copper matrix composites with different CNT defect contents were prepared via different rolling deformation processes. Their hardness and electrical conductivity were tested, and the results were consistent with the results obtained via the first-principles calculations.

14.
Materials (Basel) ; 16(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37569962

RESUMO

Composite structure design is an important way to improve reinforcement strengthening efficiency. The dispersion of the external reinforcement is often not uniform enough, however, and it is agglomerated in the matrix, which cannot uniformly and effectively bear the load. The interconnected reinforcement network prepared by the in-situ self-growth method is expected to obtain higher material properties. In this paper, the TiN shell was formed on the surface of Ti powder by the in-situ nitriding method, and then the network TiN/Ti composites were prepared by sintering. In the control group, TiN was dispersed by mechanical ball milling, and it was found that TiN powder was coated on the surface of Ti particles, and the sintered TiN/Ti composites formed a discontinuous structure with a great deal of TiN agglomeration. A uniform TiN nitride layer of 5~7 µm was formed on the surface of Ti powder by the in-situ nitriding method, and a connected TiN network was formed in the sintered Ti-N/Ti composites. The composites prepared by nitriding have higher compressive strength, hardness, and plasticity. The hardness of the Ti-N/Ti composite is 685.7 HV and the compressive strength is 1468.5 MPa. On this basis, the influence of the connected TiN structure on the material properties was analyzed, which provided theoretical guidance for the structural design of the network structure-reinforced titanium matrix composites.

15.
Materials (Basel) ; 16(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36770172

RESUMO

Composite material uses ceramic reinforcement to add to the metal matrix to obtain higher material properties. Structural design is an important direction of composite research. The reinforcement distribution of the core-shell structure has the unique advantages of strong continuity and uniform stress distribution. In this paper, a method of preparing boron carbide (B4C)-coated titanium (Ti) powder particles by ball milling and preparing core-shell B4C-reinforced Ti matrix composites by Spark Plasma Sintering was proposed. It can be seen that B4C coated on the surface of the spherical Ti powder to form a shell structure, and B4C had a certain continuity. Through X-ray diffraction characterization, it was found that B4C reacted with Ti to form layered phases of titanium boride (TiB) and titanium carbide (TiC). The compressive strength of the composite reached 1529.1 MPa, while maintaining a compressive strain rate of 5%. At the same time, conductivity and thermal conductivity were also characterized. The preparation process of the core-shell structure composites proposed in this paper has high feasibility and universality, and it is expected to be applied to other ceramic reinforcements. This result provides a reference for the design, preparation and performance research of core-shell composite materials.

16.
Chemphyschem ; 13(17): 3786-9, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23015311

RESUMO

Scatter me: A fast and cost-effective approach for the fabrication of surface-enhanced Raman scattering (SERS) arrays is developed. The method applied combines microcontact printing, electrodeposition, and galvanic replacement without the need for expensive instruments and intricate processing. The as-prepared arrays show excellent SERS activity and high reproducibility for Rhodamine 6G.


Assuntos
Cobre/química , Nanopartículas Metálicas/química , Análise em Microsséries/métodos , Nanoestruturas/química , Prata/química , Análise Espectral Raman/métodos , Campos Eletromagnéticos , Reprodutibilidade dos Testes , Rodaminas/química , Propriedades de Superfície
17.
Balkan Med J ; 39(4): 255-266, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35872625

RESUMO

Background: Circular RNAs (circRNAs) are key modulators in carcinogenesis and radioresistance in multiple kinds of human cancers. Aims: To explore the role of circ_0010235 in non-small cell lung cancer (NSCLC). Study Design: Cell culture study and animal study. Methods: The detection of circ_0010235, microRNA-588 (miR-588), and homeobox protein A10 (HOXA10) was implemented via reverse transcription-quantitative polymerase chain reaction (RT-qPCR). CCK-8, EdU, flow cytometry, transwell, and wound healing assays. These strategies were applied to evaluate cell functions. The western blot technique was employed for protein examination. The colony formation assay was used to determine cell survival after radiation treatment. In vivo research was performed by tumor xenograft assay. The binding analysis was also carried out through dual-luciferase reporter and RNA immunoprecipitation studies. Results: Circ_0010235 had an enhanced expression in NSCLC. Circ_0010235 deficiency inhibited cell proliferation, invasiveness, and migratory ability but promoted apoptosis and radiosensitivity. Downregulation of circ_0010235 decelerated tumor growth and promoted radiation sensitivity in vivo. Circ_0010235 was controlled biologically in NSCLC cells by combining with miR-588 and targeting miR-588. HOXA10 acted as a target of miR-588. MiR-588 upregulation inhibited NSCLC cell malignant phenotypes and elevated radiosensitivity via downregulating HOXA10. Circ_0010235 could regulate the level of HOXA10 by sponging miR-588. Conclusion: Circ_0010235 contributed to the malignant progression of NSCLC, but suppressed the radiation sensitivity via targeting miR- 588 to induce HOXA10 upregulation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Regulação Neoplásica da Expressão Gênica , Proteínas Homeobox A10 , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , MicroRNAs/genética , MicroRNAs/metabolismo , Fenótipo
18.
Gerontologist ; 62(4): 598-606, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-34636402

RESUMO

BACKGROUND AND OBJECTIVES: While studies have researched ageism in public policy, few investigated the impact of aging policy on ageism-typically, an unintended consequence. Ageism is linked to $63 billion in health care costs, so its antecedents are of interest. We test the association between Aging Policy Agenda Setting and Societal Age Stereotypes and hypothesize a mediating pathway via Medicalization of Aging, moderated by demographics. RESEARCH DESIGN AND METHODS: Scholars identified Singapore's Pioneer Generation Policy (PGP) as one of the largest policy implementations in recent years, where the agenda was set by the Prime Minister at an equivalent State of the Union address in 2013, and US$7 billion allocated to fund outpatient health care costs for aged 65 years or older. More than 400,000 older adults received a PGP card and home visits by trained volunteers who co-devised a personalized utilization plan. We leveraged a 10-billion-word data set with more than 30 million newspaper and magazine articles to dynamically track Societal Age Stereotype scores over 8 years from pre- to postpolicy implementation. RESULTS: Societal Age Stereotypes followed a quadratic trend: Prior to the Aging Policy Agenda Setting from 2010 to 2014, stereotypes were trending positive; after 2014, it trended downward to become more negative. Medicalization of Aging mediated the relationship between Aging Policy Agenda Setting and Societal Age Stereotypes. Furthermore, Old-age Support Ratio moderated the mediational model, suggesting that the impact of policy on medicalization is stronger when a society is more aged. DISCUSSION AND IMPLICATIONS: We provided a framework for policymakers to ameliorate the unintended consequences of aging policies on societal ageism-if unaddressed, it will exert an insidious toll on older adults, even if initial policies are well-intentioned.


Assuntos
Etarismo , Idoso , Etarismo/prevenção & controle , Envelhecimento , Custos de Cuidados de Saúde , Humanos , Políticas , Estereotipagem
19.
Nanomaterials (Basel) ; 12(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36296841

RESUMO

The scaffold layer plays an important role in transporting electrons and preventing carrier recombination in mesoporous perovskite solar cells (PSCs), so the engineering of the interface between the scaffold layer and the light absorption layer has attracted widespread concern. In this work, vertically grown TiO2 nanorods (NRs) as scaffold layers are fabricated and further treated with TiCl4 aqueous solution. It can be found that a thin brookite TiO2 nanoparticle (NP) layer is formed by the chemical bath deposition (CBD) method on the surface of every rutile NR with a low annealing temperature (150 °C), which is beneficial for the infiltration and growth of perovskite. The PSC based on the TiO2 NR/brookite NP structure shows the best power conversion of 15.2%, which is 56.37% higher than that of the PSC based on bare NRs (9.72%). This complex structure presents an improved pore filling fraction and better carrier transport capability with less trap-assisted carrier recombination. In addition, low-annealing-temperature-formed brookite NPs possess a more suitable edge potential for electrons to transport from the perovskite layer to the electron collection layer when compared with high-annealing-temperature-formed anatase NPs. The brookite phase TiO2 fabricated at a low temperature presents great potential for flexible PSCs.

20.
Nanomaterials (Basel) ; 12(13)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35808094

RESUMO

Nanomaterials play an important role in metal matrix composites (MMC). In this study, 3.0 wt.%, 6.0 wt.%, and 9.0 wt.% nano-AlN-particles-reinforced AA6061 (nano-AlN/AA6061) composites were successfully prepared by pressure infiltration technique and then hot extruded (HE) at 500 °C. The microstructural characterization of the composites after HE show that the grain structure of the Al matrix is significantly refined, varying from 2 to 20 µm down to 1 to 3 µm. Nano-AlN particles in the composites are agglomerated around the matrix, and the distribution of nano-AlN is improved after HE. The interface between AA6061 and nano-AlN is clean and smooth, without interface reaction products. The 3.0 wt.% nano-AlN/AA6061 composite shows an uppermost yield and supreme tensile strength of 333 MPa and 445 MPa, respectively. The results show that the deformation procedure of the composite is beneficial to the further dispersion of nano-AlN particles and improves the strength of nano-AlN/AA6061 composite. At the same time, the strengthening mechanism active in the composites was discussed.

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