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Thiophenol and its derivatives pose a significant threat to the environment and biological systems due to their toxic nature. The imperative need for their detection prompted the development of a "turn-on" fluorescent probe, NI-TPA-1, incorporating 1,8-naphthalimide-triphenylamine as the emission groups and 2,4-dinitrobenzene as the reactive site. Upon introducing 4-methoxythiophenol (MTP), the fluorescence intensity of NI-TPA-1 exhibited a remarkable 18-fold increase, achieving detection limits as low as 20 nM in aqueous solutions. The photo-induced electron transfer (PET) response mechanism was elucidated through density functional theory (DFT) calculations, providing valuable insights into the sensing mechanism of the probe. Furthermore, the practical applicability of NI-TPA-1 was demonstrated through its successful detection of thiophenol in real water samples. The versatility of the probe was further showcased in living cells imaging, highlighting its potential for in vivo applications. This research not only presents a robust solution for the sensitive and selective detection of thiophenol but also underscores the broader significance of NI-TPA-1 in environmental and biomedical contexts. [ABSTRACT FROM AUTHOR]

A quick, easy, cheap, effective, rugged, and safe method was developed for the multi‐residue analysis of pesticides and antibiotics in aquaculture sediment using high‐performance liquid chromatography‐tandem mass spectrometry (HPLC‐MS/MS). The developed method is based on ultrasonic extraction with acetonitrile and phosphate buffer, salting with sodium chloride, and cleaning with dispersive solid‐phase extraction adsorbent using primary secondary amine, C18, and graphitized carbon black, followed by HPLC‐MS/MS detection. We optimized different extraction methods and the ratio of the cleanup adsorbents to achieve good recoveries at three spiking levels that ranged from 60.4% to 114% with a relative standard deviation below 15% (n = 6). For all analytes, except for flufenoxuron, the limits of quantification were between 1 and 5 µg/kg (dry weight). The validated method was successfully applied to real samples collected from 20 aquacultural ponds, confirming the feasibility of the proposed method. The concentrations of the target analytes in the sediments (dry weight) were in the ranges of 2.2–35.0 µg/kg for sulfonamides, 0–409.1 µg/kg for quinolones, 0–6.56 µg/kg for macrolides, and 0–4.9 µg/kg for pesticides. Moreover, the co‐occurrence of pesticides and antibiotics may potentially pose a high risk to sediment‐dwelling organisms in nine out of the 20 investigated locations. [ABSTRACT FROM AUTHOR]

The large PV medium-voltage (MV) DC power collection system is more efficient than the traditional AC collection system, which provides an alternative for future PV applications. As one of the core components of the PV MVDC power collection system, key techniques of DC transformer are presented here in detail, including the technical requirements, and fault operation analysis in the DC collection system. When part of the PV DC module in the low-voltage (LV) side of DC transformer fails and bypassed, the DC collection system continues working normally with only part of power lost. When the MV side of DC transformer is shorted, all the PV modules exist and the collection system splits without ride-through techniques. The fault operation principle of DC transformer in PV MVDC power collection system is verified by simulations.

A ratiometric dual-mode probe NI-SH based on 1,8-Naphthalimide was prepared for H2S detection. When treated with H2S, the fluorescence of NI-SH changes from blue (456 nm) to green (540 nm), and displays significant color variation (colorless to yellow) that can visible to the naked eye. Further investigation shows that the NI-SH has high sensitivity, selectivity, and low detection limit at about 0.2 μM, and with large Stokes shift (84 nm). The intermolecular charge transfer (ICT) response mechanism of NI-SH was further studied by analyzing the distributions of the molecular orbital. Besides, NI-SH exhibits a ratiometric fluorescence response in living Hela cells. [ABSTRACT FROM AUTHOR]

The acoustic environment in an urban dwelling is a key factor in human health, especially in megacities, where there are high levels of traffic noise. This study investigated the effects of various socio-economic indicators (gender, age, roadside residence, average daily time at home) on the subjective evaluation of residential acoustic environments, employing a series of questionnaire surveys and in-depth interviews in two Chinese megacities (Chongqing and Guangzhou). The findings indicate that residents in Chongqing, a typical mountainous city, are less satisfied with their acoustic environment than those in Guangzhou, a city built on a plain. However, there were no significant differences between residents in the two Chinese megacities in terms of their perspectives on their thermal, humid or luminous environments or noise-related health symptoms. Regarding perceptions of acoustic environments, there were significant differences between residents in the mountainous city and the plain city, as well as those in roadside and non-roadside homes, but no significant differences were identified between the views of men and women or the young and the old, and time spent at home appeared to have no impact. Moreover, age and average daily time spent at home are likely to be associated with noise-related health symptoms. [ABSTRACT FROM AUTHOR]