Abstract. Brown carbon (BrC) draws increasing attention due to its effects on climate and other environmental factors. In China, household coal burned for heating and cooking purposes releases huge amounts of carbonaceous particles every year; however, BrC emissions have rarely been estimated in a persuasive manner due to the unavailable emission characteristics. Here, seven coals jointly covering geological maturity from low to high were burned in four typical stoves as both chunk and briquette styles. The optical integrating sphere (IS) method was applied to measure the emission factors (EFs) of BrC and black carbon (BC) via an iterative process using the different spectral dependence of light absorption for BrC and BC and using humic acid sodium salt (HASS) and carbon black (CarB) as reference materials. The following results have been found: (i) the average EFs of BrC for anthracite coal chunks and briquettes are 1.08 ± 0.80 and 1.52 ± 0.16 g kg−1, respectively, and those for bituminous coal chunks and briquettes are 8.59 ± 2.70 and 4.01 ± 2.19 g kg−1, respectively, reflecting a more significant decline in BrC EFs for bituminous coals than for anthracites due to briquetting. (ii) The BrC EF peaks at the middle of coal's geological maturity, displaying a bell-shaped curve between EF and volatile matter (Vdaf). (iii) The calculated BrC emissions from China's residential coal burning amounted to 592 Gg (1 Gg  =  109 g) in 2013, which is nearly half of China's total BC emissions. (iv) The absorption Ångström exponents (AAEs) of all coal briquettes are higher than those of coal chunks, indicating that the measure of coal briquetting increases the BrC ∕ BC emission ratio and thus offsets some of the climate cooling effect of briquetting. (v) In the scenario of current household coal burning in China, solar light absorption by BrC (350–850 nm in this study) accounts for more than a quarter (0.265) of the total absorption. This implies the significance of BrC to climate modeling.

Flame-retardant (FR) cotton fabrics were successfully prepared with the reactive product of (3-piperazinylpropyl)­methyldimethoxysilane and phytic acid, denoted as GPA, through a quick dip-coating technology. The structure, surface micromorphologies, thermal degradation properties, flame retardancy, and combustion properties of samples were assessed. GPA was successfully deposited on the surface of cotton fabrics, which was proved by the results of Fourier-transform infrared analysis as well as scanning electron microscopy coupled with energy dispersive spectrometry (SEM–EDS). During a vertical burning test, FR cotton-3, with an increased mass of 14.33 wt %, immediately extinguished after removing the igniter, while the control was entirely burned. The deposition of GPA to create flame-retardant cotton fabrics led to the serious decrease of heat release rate and total heat release. The promoted flame retardancy resulted from the formed thermally stable residues on the surface of cotton fabrics, which held back mass/heat transfer. Thermogravimetric analysis coupled with Fourier-transform infrared analysis (TG–FTIR) results indicated that flame-retardant cotton fabrics released more nonflammable gases (H2O and NH3) and less flammable gases than the control. According to the results of TG–FTIR, SEM–EDS, and X-ray photoelectron spectroscopy, the mechanism of the flame retardancy of GPA on the cotton fabrics was proposed.

Overexpression of HIF-1alpha is predictive of a poor outcome and might be a novel therapeutic target in human osteosarcoma.

In this work, a novel N-halamine precursor, 1-glycidyl-s-triazine-2,4,6-trione (GTT), was synthesized through the reaction of cyanuric acid with epichlorohydrin in a facile condition. The pad−dry−cure technique was used to coat GTT onto cotton fabrics through the covalent surface modification of the cotton fibers. The GTT-coated cotton was characterized by FTIR spectroscopy and SEM. The N-halamine moieties attached to the cotton fibers could be rendered antimicrobial by treatment with a dilute sodium hypochlorite solution. The N-halamine-modified cotton fabrics demonstrated excellent antimicrobial efficacy against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli O157:H7) bacteria in brief contact times. Over 71% of the chlorine lost after the equivalent of 50 machine washes could be regained upon rechlorination. The chlorinated coated fabrics showed great rechargeability within one week under UVA light irradiation.