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Waste classification is regarded as one of the most important strategies for waste management, and its success depends on the active participation of the public. Based on the theory of planned behavior (TPB) and attitude-behavior-condition (A-B-C) theory, this research investigated the key factors affecting residents' domestic waste classification intention (WCI) and waste classification behavior (WCB), and explored the moderating effects of three external factors including infrastructure (INF), government publicity (GP), and incentive measures (IM) on the intention-behavior relationship. The valid data were collected from 584 residents via conducting a face-to-face interview in Chengdu, a pilot city of waste classification in China, and analyzed by using the structural equation model (SEM). Results showed that residents' WCI and WCB had a significant discrepancy with the average values of 4.07 and 2.81, respectively. Attitude (AT), perceived behavior control (PBC) and classification knowledge (CK) were significantly related to residents' WCI, with AT (β = 0.65, P < 0.001) having the greatest direct impact. Meanwhile, CK and INF had a stronger impact on the WCB than WCI. GP indirectly affected WCB through the intermediary effect of CK. In addition, INF and GP had a positively moderating effect on residents' waste classification intention-behavior relationship and can facilitate the intention-behavior conversion. By contrast, IM failed to promote the conversion of residents' classification intention into behavior, and had no direct significant influence on residents' WCB. Finally, some relevant policy suggestions were put forward for the new pilot cities of waste classification in China. • Key factors affecting residents' WCI and WCB were investigated. • Moderating effects of external factors on intention-behavior relation was explored. • Attitude had the greatest direct influence on residents' WCI. • CK and Infrastructure had a stronger impact on WCB than WCI. • Infrastructure and GP can strengthen the intention-behavior conversion. [ABSTRACT FROM AUTHOR]

A novel method was developed for the sensitive and visual detection of p-phenylenediamine (PPD) via immobilizing the target specie PPD on dialdehyde cellulose membrane (DCM) followed by the reaction with salicylaldehyde. The obtained solid fluorescent membrane (S-PPD-DCM) emitted yellow fluorescence under 365 nm UV light. DCM was not only used as a solid matrix but also played a vital role in the enrichment of PPD. Experimental variables influencing the fluorescence signal were investigated and optimized. Under the optimum conditions, a detection limit of 5.35 μg L−1 was obtained and two linear ranges were observed at 10–100 and 100–1000 μg L−1, respectively. Moreover, the fluorescence of the resultant membrane can still be visualized by naked eye when PPD concentration was 50 μg L−1. The detection of PPD was hardly affected by the coexistence of 1 mg L−1 of o-phenylenediamine, m-phenylenediamine or p henylamine , exhibiting good selectivity. The developed method involved in a two-step Schiff base reaction and enhanced the fluorescence emission via blocking nonradiative intramolecular rotation decay of the excited molecules. It was applied to determine the PPD in spiked hair dye with satisfactory results. Image 1 • A novel method was developed for the sensitive and visual detection of PPD. • DCM as a solid matrix played a vital role in the enrichment of PPD. • The proposed method gave two linear ranges at 0.01–0.1 and 0.1–1 mg L−1, respectively. • The detection limit of PPD was calculated to be 5.35 μg L−1. • Detection mechanism was involved in two-step Schiff base reaction and AIE effect. [ABSTRACT FROM AUTHOR]

A cellulose-based composite adsorbent (PEI-PAM-CF) was fabricated via a facile cross-linking of polyethyleneimine/polyacrylamide (PEI/PAM) and cellulose using epichlorohydrin as the cross-linker. It possessed a double-network structure and emitted blue fluorescence. Compared with the control samples (PEI-CF and PAM-CF), the PEI-PAM-CF showed a synergy effect for the Cr(VI) removal. It can effectively remove Cr(VI) at low concentration with no structure destroyed for the adsorbent. Other coexisting anions (NO 3 -, Cl-, H 2 PO 4 - and CH 3 COO-) and cations (Na+, K+, Mg2+, Ca2+ and Cr3+) had no significant effect on Cr(VI) removal except SO 4 2-. After five adsorption/desorption cycles, the Cr(VI) removal only decreased with a loss of 7%, suggesting that the PEI-PAM-CF had good regeneration performance. Most importantly, the electrostatic adsorption mechanism between Cr(VI) and the PEI-PAM-CF was revealed by a reversible fluorescence "on-off-on" phenomenon and the DFT calculation. The adsorption sites on the PEI-PAM-CF were attributed to the amino groups of the PEI and PAM. Hence, the PEI-PAM-CF was potential for the treatment of Cr(VI)-containing wastewater at low concentration. [Display omitted] • A cellulose-based composite adsorbent with a dual-network structure was prepared. • The adsorbent PEI-PAM-CF can effectively uptake the low concentration Cr(VI). • A synergy effect was observed after adding PEI and PAM together. • The proposed electrostatic adsorption mechanism was clarified. • The DFT calculation was performed to study the adsorption sites. [ABSTRACT FROM AUTHOR]