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1.
Psychol Res Behav Manag ; 16: 95-108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36660257

RESUMO

Purpose: This study examined the influencing mechanism and boundary conditions underlying the relation between COVID-19 perceived risk and flight attendants' turnover intention by investigating the mediating role of job insecurity and the moderating effect of job crafting. Methods:  A two-wave survey was conducted with 240 Chinese flight attendants. We used structural equation modeling to test the moderated mediation model. Results: The results indicated that perceived risk of COVID-19 positively affected flight attendants' job insecurity and turnover intention. Moreover, job insecurity plays a fully mediating role in the relationship between perceived risk and turnover intention. Furthermore, the mediating role of job insecurity was moderated by job crafting; for higher levels of job crafting (opposed to low), the effect of job insecurity on turnover intention was significantly weaker. Conclusion:  Our findings indicate that dissipating job insecurity and increasing job crafting behavior are critical to employees' work-related attitudes and behavior during the COVID-19 pandemic.

2.
Int J Mol Sci ; 25(1)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38203239

RESUMO

Bacterial cellulose, as an important renewable bioresource, exhibits excellent mechanical properties along with intrinsic biodegradability. It is expected to replace non-degradable plastics and reduce severe environmental pollution. In this study, using dry jet-wet spinning and stretching methods, we fabricate cellulose composite macrofibers using nanofibrillated bacterial cellulose (BCNFs) which were obtained by agitated fermentation. Ionic liquid (IL) was used as a solvent to perform wet spinning. In this process, force-induced alignment of BCNFs was applied to enhance the mechanical properties of the macrofibers. The results of scanning electron microscopy revealed the well-aligned structure of BCNF along the fiber axis. The fiber prepared with an extrusion rate of 30 m min-1 and a stretching ratio of 46% exhibited a strength of 174 MPa and a Young's modulus of 13.7 GPa. In addition, we investigated the co-spinning of carboxymethyl cellulose-containing BCNF with chitosan using IL as a "container", which indicated the compatibility of BCNFs with other polysaccharides. Recycling of the ionic liquid was also verified to validate the sustainability of our strategy. This study provides a scalable method to fabricate bacterial cellulose composite fibers, which can be applied in the textile or biomaterial industries with further functionalization.


Assuntos
Quitosana , Líquidos Iônicos , Celulose , Materiais Biocompatíveis , Carboximetilcelulose Sódica
3.
Macromol Rapid Commun ; 42(6): e2000496, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33200484

RESUMO

Hantzsch reaction is one of the typical multicomponent reactions (MCRs), and it is employed herein to endow cellulosic materials with fluorescent properties. For example, acetoacetyl (ACAC)-bearing cotton fabric prepared via transesterification with tert-butyl acetoacetate is subjected to an aqueous Hantzsch reaction with formaldehyde and ammonium acetate at ambient temperature. A strong fluorescent emission around 460 nm is achieved within 10 min. XPS, fluorescent spectroscopy, and elemental analysis are used to confirm the presence of 1,4-dihydropyridine (DHP) rings on the surface of the fabric. TGA, SEM, XRD, and mechanical testing results show that the modification process has minimum impact on intrinsic properties of the fabric. The strategy is also shown to be generally applicable to various forms of cellulosic materials and different aldehydes. This fast and simple approach enriches the application of MCR in modification of cellulose and cellulose derivatives.


Assuntos
Aldeídos , Celulose , Corantes , Água
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