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1.
Cereb Cortex ; 34(2)2024 01 31.
Article in English | MEDLINE | ID: mdl-38236724

ABSTRACT

An increasing number of studies have shown that flight training alters the human brain structure; however, most studies have focused on gray matter, and the exploration of white matter structure has been largely neglected. This study aimed to investigate the changes in white matter structure induced by flight training and estimate the correlation between such changes and psychomotor and flight performance. Diffusion tensor imaging data were obtained from 25 flying cadets and 24 general college students. Data were collected in 2019 and 2022 and analyzed using automated fiber quantification. This study found no significant changes in the flight group in 2019. However, in 2022, the flight group exhibited significant alterations in the diffusion tensor imaging of the right anterior thalamic radiation, left cingulum cingulate, bilateral superior longitudinal fasciculus, and left arcuate fasciculus. These changes occurred within local nodes of the fiber tracts. In addition, we found that changes in fiber tracts in the 2022 flight group were correlated with the reaction time of the psychomotor test task and flight duration. These findings may help improve flight training programs and provide new ideas for the selection of excellent pilots.


Subject(s)
White Matter , Humans , White Matter/diagnostic imaging , Diffusion Tensor Imaging/methods , Brain/diagnostic imaging , Gray Matter , Nerve Fibers , Anisotropy
2.
Environ Sci Pollut Res Int ; 30(20): 58362-58377, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36988808

ABSTRACT

Urban heat island (UHI) is one of the important effects of urbanization on built environment. Land surface temperature data was taken from moderate-resolution imaging spectroradiometer (MODIS) to investigate the long-term spatiotemporal patterns of UHI in Wuhan during 2001~2018 and, the UHI intensity changes of built-up land in 13 administrative regions in Wuhan were analyzed. Furthermore, 34 spatial error models and 34 ordinary least squares models were established and compared. Spatial error models showed good fitting effect, which were used to determine the influence of normalized difference vegetation index (NDVI), normalized difference building index (NDBI), and social-economic factors (population and nighttime light) on UHI intensity in central urban area and new urban area. The explanatory power changes of these four indicators during 2001~2018 were explored as well. The average UHI intensity in 2014~2018 has increased by about 0.45 °C compared to that in 2001~2005. NDBI is the most dominant factor contributing to the increase in temperature. The impact of NDVI on UHI intensity changes from negative to positive, and the impact of NDBI on UHI intensity in central urban area is weakened during 2001-2018. Social-economic factors have a greater impact on new urban area than on central urban area. These findings show the effects and the explanatory power changes of driving factors during 18 years, which can provide a better understanding of the formation and development of UHI and support for the future urban planning of Wuhan.


Subject(s)
Environmental Monitoring , Hot Temperature , Cities , Environmental Monitoring/methods , Urbanization , China
3.
Macromol Rapid Commun ; 43(15): e2200040, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35258142

ABSTRACT

Aqueous asymmetric supercapacitor has captured widespread attention as a sustainable high-power energy resource. Organic electrode materials are appealing owing to their sustainability and high redox reactivity, but suffer from structural instability and low power density. Here the π-conjugated polyimide-based organic electrodes with different lengths of alkyl chains are explored to achieve high rate capability and long lifespan in an aqueous K+ -ion electrolyte. The fabricated asymmetric supercapacitor exhibits high capacities of 107 mAh g-1 at 2 A g-1 and 67 mAh g-1 at 90 A g-1 . A specific capacity of 65 mAh g-1 over 70% of the initial performance is obtained after 65 000 cycles. Molecular engineering of long alkyl chains in polyimide can reduce the degree of π-conjugation and spatially block the π-conjugated imide bond with limited redox activity but improved stability against chemical degradation. Further electrochemical quartz crystal microbalance, ex-situ Fourier transformed infrared spectroscopy, and X-ray photoelectron spectroscopy characterizations reveal the pseudocapacitance behavior originating from the π-conjugated polyimide-based redox reaction with potassium ions and hydrated potassium ions. A promising polyimide-based polymer with extended π-conjugated system for high-performance asymmetric supercapacitor is showcased.

4.
Chem Commun (Camb) ; 57(46): 5634-5637, 2021 Jun 08.
Article in English | MEDLINE | ID: mdl-33977952

ABSTRACT

Pure organic dye QAP-C8 based on quinacridone (QA) with octyl side chains as the donor and pyridine dicarboxylic acid (PDA) as the acceptor was first used in both the photoanode and the photocathode of photoelectrochemical cells. A tandem device with QAP-C8 as the photosensitizer realized overall water splitting and showed a STH of 0.11% under neutral pH conditions without an external bias.


Subject(s)
Coloring Agents/chemistry , Electrochemical Techniques , Heterocyclic Compounds, 4 or More Rings/chemistry , Photosensitizing Agents/chemistry , Solar Energy , Hydrogen-Ion Concentration , Photochemical Processes , Water/chemistry
5.
Light Sci Appl ; 10(1): 63, 2021 Mar 25.
Article in English | MEDLINE | ID: mdl-33767137

ABSTRACT

With inherent orthogonality, both the spin angular momentum (SAM) and orbital angular momentum (OAM) of photons have been utilized to expand the dimensions of quantum information, optical communications, and information processing, wherein simultaneous detection of SAMs and OAMs with a single element and a single-shot measurement is highly anticipated. Here, a single azimuthal-quadratic phase metasurface-based photonic momentum transformation (PMT) is illustrated and utilized for vortex recognition. Since different vortices are converted into focusing patterns with distinct azimuthal coordinates on a transverse plane through PMT, OAMs within a large mode space can be determined through a single-shot measurement. Moreover, spin-controlled dual-functional PMTs are proposed for simultaneous SAM and OAM sorting, which is implemented by a single spin-decoupled metasurface that merges both the geometric phase and dynamic phase. Interestingly, our proposed method can detect vectorial vortices with both phase and polarization singularities, as well as superimposed vortices with a certain interval step. Experimental results obtained at several wavelengths in the visible band exhibit good agreement with the numerical modeling. With the merits of ultracompact device size, simple optical configuration, and prominent vortex recognition ability, our approach may underpin the development of integrated and high-dimensional optical and quantum systems.

6.
Nanoscale Adv ; 3(6): 1699-1707, 2021 Mar 23.
Article in English | MEDLINE | ID: mdl-36132554

ABSTRACT

Polymeric carbon nitride (g-C3N4) has succeeded as a striking visible-light photocatalyst for solar-to-hydrogen energy conversion, owing to its economical attribute and high stability. However, due to the lack of sufficient solar-light absorption and rapid photo-generated carrier recombination, the photocatalytic activity of raw g-C3N4 is still unsatisfactory. Herein, new intramolecular g-C3N4-based donor-acceptor (D-A) conjugated copolymers have been readily synthesized by a nucleophilic substitution/condensation reaction between urea and 3,7-dihydroxydibenzo[b,d]thiophene 5,5-dioxide (SO), which is strategically used to improve the photocatalytic hydrogen evolution performance. The experimental results demonstrate that CNSO-X not only improves light utilization, but also accelerates the spatial separation efficiency of the photogenerated electron-hole pairs and increases the wettability with the introduction of SO. In addition, the adsorption energy barrier of CNSO-X to H* has a significant reduction via theoretical calculation. As expected, the CNSO-20 realizes the best photocatalytic H2 evolution activity of 251 µmol h-1 (50 mg photocatalyst, almost 8.5 times higher than that of pure CN) with an apparent quantum yield of 10.16% at 420 nm, which surpasses most strategies for the organic molecular copolymerization of carbon nitride. Therefore, this strategy opens up a novel avenue to develop highly efficient g-C3N4 based photocatalysts for hydrogen production.

7.
Energy (Oxf) ; 213: 118792, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-32929299

ABSTRACT

Building energy consumption in the Asia-Pacific region continues to rise. It is important to understand the energy use and future trends of 21 members of Asia-Pacific Economic Cooperation (APEC) and to find more effective ways to achieve APEC's dual goals of reducing energy intensity by 45% of 2005 levels by 2035 and doubling the share of renewable energy in the energy mix between 2010 and 2030. Recently, promoting building toward ultra-low energy, nearly zero energy and zero energy is becoming a consensus trend. This paper aims to explore how zero energy building promotion could influence the total energy demand in the mid to long term. An EUPP (Economic, Urbanization, Population and Purchasing power parity) model was established to show the relationship between building energy consumption and its influencing factors, and the potential development path of building energy consumption in APEC was predicted by using the model. The results show that in the Business As Usual (BAU) model, building energy demand will increase from 1387.4 Mtoe in 2016 to 2456.8 Mtoe in 2050 while in the CAP model, building energy demand will be constrained to under 2000 Mtoe before 2050. In the ZEB promotion model, 897.8 to 1945.3 Mtoe could be saved separately. The share of end demand supplied by onsite renewable energy production could reach 11%-54%. The building sector has the potential to become the largest contributor to achieve the APEC energy goal and thus to the climate change goal.

8.
Chem Commun (Camb) ; 55(56): 8090-8093, 2019 Jul 09.
Article in English | MEDLINE | ID: mdl-31231736

ABSTRACT

In this communication, a self-assembled supramolecular system consisting of phosphoric acid substituted perylene diimide (P-PMPDI) has been successfully developed for highly efficient photocatalytic hydrogen evolution. Compared with a carboxylic substituent perylene diimide (P-CMPDI), P-PMPDI showed a superior H2 evolution reaction rate of 11.7 mmol g-1 h-1 and a recorded apparent quantum yield (AQY) of 2.96% at 550 nm.

9.
ACS Omega ; 3(10): 14448-14456, 2018 Oct 31.
Article in English | MEDLINE | ID: mdl-31458130

ABSTRACT

Two dyes TB and TSB containing triphenylamine as the donor and perylenemonoimide as the acceptor, with and without bithiophene as π-bridge, respectively, were successfully prepared and characterized for p-type dye-sensitized solar cells (p-DSSCs) and dye-sensitized photoelectrochemical cells (DS-PECs). As a result, TSB with bithiophene π-bridge exhibited a broader absorption spectrum and a higher molar extinction coefficient than TB. Furthermore, the photocurrents of p-DSSCs and DS-PECs for the dye TSB were increased by 26.9 and 32.9%, respectively, compared with those of the dye TB. Meanwhile, the electrochemical impedance spectroscopy of the TSB-based p-DSSC showed the smaller charge-transfer resistance and larger hole lifetime because the longer π-bridge facilitated charge transfer and separation within the dye molecule and effectively prevented the hole recombination process at the NiO/dye interface, resulting in improvement of photoelectric performance. Hence, these results show that the π-bridge extension of dyes has a promising effect on the photocurrent improvement of p-DSSCs and DS-PECs.

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