Comprehensive Study on Cellulose Swelling for Completely Recyclable Nonaqueous Reactive Dyeing

The swelling of cotton by non-nucleophilic organic solvents was investigated to achieve completely recyclable reactive dyeing. The degree of swelling was determined and correlated to the Hansen Solubility Parameter distance (<i>Ra</i>) of cellulose to the solvents and the dielectric constant of the solvents (ε). The effect of swelling temperature was also investigated. Preswelling of cotton fabrics by 150 °C <i>N</i>,<i>N</i>-dimethylacetamide (DMAc) for 1 h was found to be sufficient to accelerate dye sorption. Dyeing was carried out using C.I. Reactive Red 24 in a 40/60 mixture of DMAc and dimethylcarbonate (DMC), a cosolvent selected to facilitate dye exhaustion. The efficiency of unfixed dye removal was found to predominantly correlate to swelling (<i>R</i>² = 0.9236). Excellent colorfastness was achieved with 4 rinses by 95 °C DMAc. A 10-cycle repeated dyeing sequence was demonstrated to give 43% and 90% reduction in dye consumption and disposal. The overall reduction in material disposal was estimated to be over 99.99%. The favorable results indicated that discharge-free reactive dyeing could be made possible

Table_1_Potential immune evasion of the severe acute respiratory syndrome coronavirus 2 Omicron variants.pdf

Coronavirus disease 2019 (COVID-19), which is caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a global pandemic. The Omicron variant (B.1.1.529) was first discovered in November 2021 in specimens collected from Botswana, South Africa. Omicron has become the dominant variant worldwide, and several sublineages or subvariants have been identified recently. Compared to those of other mutants, the Omicron variant has the most highly expressed amino acid mutations, with almost 60 mutations throughout the genome, most of which are in the spike (S) protein, especially in the receptor-binding domain (RBD). These mutations increase the binding affinity of Omicron variants for the ACE2 receptor, and Omicron variants may also lead to immune escape. Despite causing milder symptoms, epidemiological evidence suggests that Omicron variants have exceptionally higher transmissibility, higher rates of reinfection and greater spread than the prototype strain as well as other preceding variants. Additionally, overwhelming amounts of data suggest that the levels of specific neutralization antibodies against Omicron variants decrease in most vaccinated populations, although CD4+ and CD8+ T-cell responses are maintained. Therefore, the mechanisms underlying Omicron variant evasion are still unclear. In this review, we surveyed the current epidemic status and potential immune escape mechanisms of Omicron variants. Especially, we focused on the potential roles of viral epitope mutations, antigenic drift, hybrid immunity, and “original antigenic sin” in mediating immune evasion. These insights might supply more valuable concise information for us to understand the spreading of Omicron variants.</p

Green Finishing of Cotton Fabrics Using a Xylitol-Extended Citric Acid Cross-linking System on a Pilot Scale

Cross-linking is frequently applied to cotton fabrics for enhanced wrinkle recovery and dimensional stability. The combination of citric acid (CA) and xylitol shows great potential as a sustainable alternative to the market-dominating <i>N</i>-methylol resins, which are inherently formaldehyde-releasing. This paper reports a successful pilot-scale application of this green cross-linking system preceded by systematic investigation using response surface methodology (RSM). Responses of fabric properties to five foremost variables were investigated to gain insight of the cross-linking system and facilitate its industrialization. The model obtained by RSM suggests that curing temperature is the most prominent variable and the responses to CA and xylitol concentrations are closely coupled. The optimum conditions used for the pilot-scale experiments were 3 min, 175 °C, 130 g/L, 15 g/L, and 3 kg/cm² for curing time, curing temperature, CA concentration, xylitol concentration, and padder-roll pressure, respectively. The CA/xylitol finished fabrics were comparable to those finished with the market-dominating dimethylol­dihydroxy­ethylene­urea (DMDHEU) resins. Analyses show that CA/xylitol is more cost-effective than other formaldehyde-free cross-linking agents and clearly has a more preferable environmental, health, and safety (EHS) profile than DMDHEU. The encouraging results indicate that CA/xylitol has great potential in replacing <i>N</i>-methylol resins on an industrial scale

Additional file 1: of Polyaniline-Coated Activated Carbon Aerogel/Sulfur Composite for High-performance Lithium-Sulfur Battery

Supporting information. Figure S1. TEM images of (a) ACA-500-S and the corresponding elemental mapping for (b) carbon, (c) sulfur, (d) oxygen. Figure S2. STEM images of (a) ACA-500-S@PANi and the corresponding elemental mapping for (b) carbon, (c) nitrogen, (d) sulfur, and (d) oxygen. Figure S3. The total XPS spectra of (a) ACA-500-S, (b) C 1s, and (c) S 2p spectra of ACA-500-S. The peaks at 164.0 and 165.2 eV in (c) indicate that the uniformly encapsulated sulfur exists in the form of elemental sulfur. Figure S4. (a) The total XPS spectra and (b) N 1s spectrum of ACA-500-S@PANi. Figure S5. Discharge-charge curves at various rates for (a) ACA-500-S@PANi and (b) ACA-500-S cathodes. Figure S6. Discharge-charge curves recorded at different cycles for (a) ACA-500-S@PANi and (b) ACA-500-S cathodes at 1C. Figure S7. TGA curves of (a) ACA-500-S-70% (black), ACA-500-S@PANi-61% (blue), and ACA-500-S@PANi-55% (red) and (b) ACA-500-S-54% (violet) and ACA-500-S@PANi-45% (olive). Figure S8. (a) Rate performances of ACA-500-S-54% and ACA-500-S@PANi-55% cathodes. Discharge-charge curves at various rates for (b) ACA-500-S@PANi-55% and (c) ACA-500-S-54% cathodes. (d) Cycle performances of ACA-500-S@PANi-45% and ACA-500-S@PANi-61% cathodes at 1C. Table S1. Textual characteristic of ACA-500, ACA-500-S, and ACA-500-S@PANi. Table S2. Summary of cycle stability performances of representative conductive PANi coating for carbon/S cathodes at 1 C rate. (DOCX 980 kb

Water-Dispersible, Responsive, and Carbonizable Hairy Microporous Polymeric Nanospheres

Multifunctionalization of microporous polymers is highly desirable but remains a significant challenge, considering that the current microporous polymers are generally hydrophobic and nonresponsive to different environmental stimuli and difficult to be carbonized without damage of their well-defined nanomorphology. Herein, we demonstrate a facile and versatile method to fabricate water-dispersible, pH/temperature responsive and readily carbonizable hairy microporous polymeric nanospheres based on combination of the hyper-cross-linking chemistry with the surface-initiated atom transfer radical polymerization (SI-ATRP). The hyper-cross-linking creates a highly microporous core, whereas the SI-ATRP provides diverse functionalities by surface grafting of hairy functional blocks. The as-prepared materials present multifunctional properties, including sensitive response to pH/temperature, high adsorption capacity toward adsorbates from aqueous solution, and valuable transformation into well-defined microporous carbon nanospheres because of hybrid of carbonizable core and thermo-decomposable protection shell. We hope this strategy could promote the development of both functional microporous polymers and advanced hairy nanoparticles for multipurpose applications

Tuning the Solvent Alkyl Chain to Tailor Electrolyte Solvation for Stable Li-Metal Batteries

1,2-Dimethoxyethane (DME) has been considered as the most promising electrolyte solvent for Li-metal batteries (LMBs). However, challenges arise from insufficient Li Coulombic efficiency (CE) and poor anodic stability associated with DME-based electrolytes. Here, we proposed a rational molecular design methodology to tailor electrolyte solvation for stable LMBs, where shortening the middle alkyl chain of the solvent could reduce the chelation ability, while increasing the terminal alkyl chain of the solvent could increase the steric hindrance, affording a diethoxymethane (DEM) solvent with ultra-weak solvation ability. When serving as a single solvent for electrolyte, a peculiar solvation structure dominated by contact ion pairs (CIPs) and aggregates (AGGs) was achieved even at a regular salt concentration of 1 m, which gives rise to anion-derived interfacial chemistry. This illustrates an unprecedentedly high Li||Cu CE of 99.1% for a single-salt single-solvent (non-fluorinated) electrolyte at ∼1 m. Moreover, this 1 m DEM-based electrolyte also remarkably suppresses the anodic dissolution of Al current collectors and significantly improves the cycling performance of high-voltage cathodes. This work opens up new frontiers in engineering electrolytes toward stable LMBs with high energy densities