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1.
Int J Health Geogr ; 23(1): 7, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454436

RESUMO

Current research on public spaces and mental health often focuses on the independent relationship of one or more social mediators, neglecting the nuanced implications and serial mechanisms inherent in the progressive social process. Using Wuhan city, China, as a study case with multi-source data, this research applies Multilevel Generalized Structural Equation Modeling and deep learning techniques to explore the differential effects of public spaces with varying degrees of publicness (i.e., typical, semi-, and privately owned) on rural migrants' mental health. Crucially, this study scrutinizes both explicit (social interaction) and implicit (perceived integration) social mechanisms to revisit the relationships. The findings reveal that not all public spaces equally influence mental health, with typical and privately owned public spaces conferring profound benefits. Notably, public spaces impact mental health chiefly through perceived integration instead of through direct social interaction. Social interaction improves mental health primarily by enhancing perceived integration, suggesting that meaningful connections beyond superficial encounters are critical. In particular, we observed significant social effects in typical and privately owned public spaces but limited social functionality in semi-public spaces. This evidence contributes to the knowledge required to create supportive social environments within public spaces, integral to nurturing inclusive urban development.


Assuntos
Saúde Mental , Migrantes , Humanos , Cidades , Meio Ambiente , China/epidemiologia
2.
Sensors (Basel) ; 23(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38139654

RESUMO

This paper presents a low-voltage low-power chopper-stabilized differential difference amplifier (DDA) realized using 40 nm CMOS technology. Operating with a supply voltage of 0.5 V, a three-stage DDA has been employed to achieve an open-loop gain of 89 dB, while consuming just 0.74 µW of power. The proposed DDA incorporates feed-forward frequency compensation and a Type II compensator to achieve pole-zero cancellation and damping factor control. The DDA has a unity-gain bandwidth (UGB) of 170 kHz, a phase margin (PM) of 63.98°, and a common-mode rejection ratio (CMRR) of up to 100 dB. This circuit can effectively drive a 50 pF capacitor in parallel with a 300 kΩ resistor. The use of the chopper stabilization technique effectively mitigates the offset and 1/f noise. The chopping frequency of the chopper modulator is 5 kHz. The input noise is 245 nV/sqrt (Hz) at 1 kHz, and the input-referred offset under Monte Carlo cases is only 0.26 mV. Such a low-voltage chopper-stabilized DDA will be very useful for analog signal processing applications. Compared to the reported chopper DDA counterparts, the proposed DDA is regarded as that with one of the lowest supply voltages. The proposed DDA has demonstrated its effectiveness in tradeoff design when dealing with multiple parameters pertaining to power consumption, noise, and bandwidth.

3.
Chem Commun (Camb) ; 59(85): 12747-12750, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37807889

RESUMO

Through chelating-assisted impregnation with diethylenetriamine-pentaacetic acid (DTPA), we developed an efficient and durable CO2 hydrogenation catalyst, In15/m-ZrO2-DTPA, featuring improved In2O3 reducibility and interfacial Zr-O-In structures. Benefiting from its distinct CO2 activation and hydrogenation ability, In15/m-ZrO2-DTPA exhibited remarkable CO2-to-methanol catalytic activity, achieving up to 91% selectivity at 260 °C and 5.0 MPa, with consistent conversion maintained over 400 hours.

4.
Chem Commun (Camb) ; 59(49): 7647-7650, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37259557

RESUMO

Oxygen vacancy-enriched ultrafine tetragonal ZrO2 was introduced as a support for copper nanoparticles to enhance the energy efficiency of CO2 hydrogenation for methanol synthesis. In situ spectroscopic techniques confirmed the oxygen vacancy-mediated single-electron CO2 activation. The resulting highly efficient catalyst yielded a methanol production rate of 550 mg gcat-1 h-1 at 200 °C, outperforming state-of-the-art Cu-based catalysts.


Assuntos
Dióxido de Carbono , Cobre , Metanol , Elétrons , Oxigênio
5.
Chem Commun (Camb) ; 56(88): 13536-13539, 2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33064118

RESUMO

High pressure reforming of methane is critical for process economics, but imposes increased risk of catalyst coke deposition. Herein, a coke- and sintering-resistant Ir-Ni alloy catalyst is presented, which is durable in methane bi-reforming at 850 °C and 20 bars for up to 434 h.

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