13 research outputs found
Prediction of the dynamic distribution for Eucheuma denticulatum (Rhodophyta, Solieriaceae) under climate change in the Indo-Pacific Ocean
Submitted version (preprint).This is a preprint of an article published by Elsevier in Marine Environmental Research on 23.08.2022.Available online: doi.org/10.1016/j.marenvres.2022.105730submittedVersio
Resilience mediates the association between alexithymia and stress in Chinese medical students during the COVID-19 pandemic
Background Evidence indicates that medical students have had high rates of mental health problems, especially during the COVID-19 pandemic, which could be affected by alexithymia—a marked dysfunction in emotional awareness, social attachment and interpersonal relationships—and stress. However, psychological resilience might relieve alexithymia and stress levels.Aims This study aimed to investigate the role of resilience in alexithymia and stress in medical students.Methods A total of 470 medical students completed online and offline surveys, including the Toronto Alexithymia Scale-20 (TAS-20), the Connor-Davidson Resilience Scale (CD-RISC) and the College Student Stress Questionnaire (CSSQ). The data of five participants were excluded because of a lack of integrity. Mann-Whitney U test or Kruskal-Wallis test was used to compare group differences in the CD-RISC scores among categorical variables. Spearman correlation analysis was employed to evaluate the associations between resilience and alexithymia and between resilience and stress. Mediation analysis was used to test the mediating effect of resilience between alexithymia and stress.Results Of the medical students considered in the analysis, 382 (81.28%) were female and 88 (18.72%) were male. There was a significant negative correlation between the TAS-20 scores and the total and subtotal CD-RISC scores (p<0.001). The CSSQ scores also significantly negatively correlated with the total and subtotal CD-RISC scores (p<0.001). Resilience mediated the relationship between alexithymia and stress (total effect=1.044 7, p<0.001). The indirect effect of alexithymia significantly impacted stress through resilience (effect=0.167 0, 95% CI: 0.069 to 0.281).Conclusions Our findings suggest that resilience might effectively reduce alexithymia and stress. They also contributed to a better understanding of the mediating effects of resilience on alexithymia and stress during the COVID-19 pandemic. The evidence from these results encourages universities to focus on improving students’ resilience
Unanticipated Strong Blue Photoluminescence from Fully Biobased Aliphatic Hyperbranched Polyesters
Nonconventional fluorescent
polymers without π-aromatic structure
have attracted extensive interest in recent years. Hyperbranched polyesters
are generally known because of their industrial applications; however,
the luminescent properties of the polyester has not been reported.
Herein, we synthesized a series of fully biobased aliphatic hyperbranched
polyesters via a one-pot A<sub>2</sub> + B<sub>3</sub> esterification
reaction. Intriguingly, the resultant hyperbranched polyesters carrying
no conventional fluorescent units exhibited unexpected bright blue
fluorescence under 365 nm UV light. It was found that the fluorescence
intensity was enhanced with increasing solution concentrations and
molecular weights of the polyesters. Moreover, the results suggested
that the luminescence of polyesters could be controlled by solvents
and metal ions. In particular, the fluorescence of the polyesters
was extremely sensitive to Fe<sup>3+</sup>. More interesting is that
the fluorescence of the polyesters showed an aggregation-induced enhanced
emission in the mixture system. Notably, the resulting polyesters
displayed a remarkably enhanced quantum yield (16.75%) as compared
with that of other types of these polymers. Preliminary results demonstrate
that clustering of the carbonyl groups is responsible for the unusual
fluorescence in the aliphatic hyperbranched polyesters, namely, clustering-induced
emission (CIE). This study provides a novel perspective for the design
of biobased luminescent materials to new application areas
Zerovalent Selenium Adsorption Mechanisms on CaO Surface: DFT Calculation and Experimental Study
Zerovalent Se (Se
atom and small Se<sub>2</sub> molecule) adsorption
mechanisms on a CaO surface were studied by both density functional
theory (DFT) calculations and adsorption experiments. Nonvalent Se
adsorption on the CaO(001) surface was simulated using a slab model.
The adsorption energy, adsorption structure, electron density clouds,
and electron properties were calculated. Different Se surface coverages
were investigated to elucidate the adsorption process. In the experiments,
the Se adsorption products were prepared in a U-shaped quartz reactor
at 300 °C. The properties were investigated by X-ray photoelectron
spectroscopy (XPS), inductively coupled plasma atomic emission spectroscopy
(ICP-AES), field emission scanning electron microscopy/energy dispersive
X-ray spectroscopy (FE-SEM/EDS), and X-ray diffraction (XRD), respectively.
The experimental results match up with the DFT results, which reveal
fundamental monochemisorption mechanisms of zerovalent Se on
the CaO surface
Catalytic Oxidation and Adsorption of Elemental Mercury over CuCl<sub>2</sub>‑Impregnated Sorbents
CuCl<sub>2</sub>-impregnated sorbents
were employed to remove elemental
mercury from flue gas. Three carriers including neutral Al<sub>2</sub>O<sub>3</sub>, artificial zeolite, and activated carbon have been
investigated in this research. The performances of these prepared
sorbents have been tested in a bench-scale fixed-bed reactor under
different simulated flue gas atmospheres and temperatures (333–573
K). CuCl<sub>2</sub>-impregnated activated carbon showed the best
adsorption ability. However, CuCl<sub>2</sub>-impregnated neutral
Al<sub>2</sub>O<sub>3</sub> and zeolite have demonstrated an adsorption
rate similar to that of CuCl<sub>2</sub>-impregnated activated carbon
in the early stage of the tests (5 min), and they achieved relatively
high mercury oxidation efficiencies. These non-carbon sorbents could
remarkably enhance the technoeconomical properties of mercury removal
in coal-fired power plants and have great potentials in industrial
application. The appropriate mercury capture temperature for these
sorbents is 333–473 K. The possible mechanisms of elemental
mercury oxidation have been discussed