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Comprehensive Summary It is urgent to recycle polyethylene terephthalate (PET) effectively, since it is the most consumed synthetic polyester and its improper disposal has caused significant environmental pollution. The existing chemical recycling methods highly rely on the nucleophilic substitutions and hydrogenative depolymerizations, which typically require the use of excess of nucleophiles, excess strong acids or bases, expensive metal catalysts, and explosive gas atmosphere. Here, we demonstrate a mild and efficient protocol for oxidative depolymerization of PET to terephthalic acid using only an O2 balloon. Terephthalic acid can be recycled from PET‐containing materials including a series of plastic products in daily life. The employing of relatively low loading of iron complex, the most earth‐abundant transition metal, as the catalyst and the preliminary results on the large‐scale reaction using 38 g of PET waste demonstrate the practical feasibility of this degradation method. This method can be also applicable for selective degradation of PET from mixed plastics. This work represents a rare example of a selective oxidative depolymerization and demonstrates the great potentials of such a concept in polyester recycling. [ABSTRACT FROM AUTHOR]

Wang, S.; Liu, D., and Wang, Z., 2018. Feature analysis and control method of seepage deformation of rock and soil in port and coast. In: Liu, Z.L. and Mi, C. (eds.), Advances in Sustainable Port and Ocean Engineering. Journal of Coastal Research, Special Issue No. 83, pp. 436–441. Coconut Creek (Florida), ISSN 0749-0208. It is difficult to effectively reflect seepage deformation features and development process of rock and soil by detecting the seepage hazard of rock and soil and concentrated seepage channel using current seepage deformation feature analysis methods. It cannot directly evaluate the anti-seepage performance of coastal rock and soil. This paper presents a method for analysis and control of seepage deformation of rock and soil in port and coast. By determining the type of seepage deformation of soil and the critical hydraulic slope or the allowable hydraulic slope, it is determined whether the dam foundation is deformed due to seepage by the comparison between the critical hydraulic gradient and the actual hydraulic gradient, so as to develop a reasonable and effective control plan. The experimental results show that the proposed method can provide the theoretical basis for the construction of port and coast engineering, and seepage prevention and reduction for dam foundation. [ABSTRACT FROM AUTHOR]

Wang, S.; Liu, D., and Wang, Z., 2018. The stability and reliability of the marine anchor rock mass under wave action. In: Liu, Z.L. and Mi, C. (eds.), Advances in Sustainable Port and Ocean Engineering. Journal of Coastal Research, Special Issue No. 83, pp. 6–11. Coconut Creek (Florida), ISSN 0749-0208. At present, most of the stability and reliability analysis of the coastal and anchor rocks is based on the genetic algorithm, while there is a problem that the efficiency of analysis is low. In this paper, a steady and reliability analysis method based on the wave action of the equivalent plastic strain is proposed. Firstly, the analysis model is established, and the uniform design method, radial basis neural network technology and maximum entropy principle are combined on this basis to complete the stability and reliability analysis. Experiments show that compared with traditional method, the error between the ultimate bearing capacity and the actual ultimate bearing capacity of the method in this paper is smaller, the stability and reliability analysis of the anchorage rock solid with different water content is more accurate and the effect is better. [ABSTRACT FROM AUTHOR]

A mild and efficient synthesis of 3,3-disubstituted oxindoles is achieved. The corresponding diazonium salts are generated in situ from aromatic amines before these salts undergo a homolytic bond cleavage to produce the aryl radicals. Various oxindoles are obtained by homolytic aromatic substitution and radical cyclization. This procedure is an alternative method to oxindole synthesis. [ABSTRACT FROM AUTHOR]

A highly efficient amidation reactionof heterocycles with N-fluorobenzenesulfonimide (NFSI)has been developed, presumablyproceeding via C–H bond activation. Cuprous iodide was employedas the catalyst, and various α-amidated heterocycle derivativeshave been generated in good to excellent yields. This chemistry endowedan economic method of synthesis of valuable amidated heterocyclesthrough a direct C–N bond-coupling processes. [ABSTRACT FROM AUTHOR]

Abstract: A novel synthetic strategy to alkynyl sulfides via transition-metal-free catalyzed C–S coupling of 1,1-dibromo-1-alkenes with thiophenols has been developed. The new strategy which avoided the transition-metal toxicities is environmental friendly and very important for alkynyl sulfides synthesis. [Copyright &y& Elsevier]

Abstract: Pd(II)-catalyzed intramolecular C–H activation/C–C cross coupling within N,N-diphenyl-acetamides allows the efficient formation of differently substituted carbazoles. In this cross-dehydrogenative coupling, many different functional groups are tolerated and the starting material N,N-diphenyl-acetamides can be easily prepared in one step from commercially available acetanilides and iodobenzenes. [Copyright &y& Elsevier]

A recent study published in the journal Synlett discusses a new method for the chemical recycling of plastic waste, specifically polystyrene. The study focuses on the use of an iron-based catalyst to degrade polystyrene into benzoic acid under mild conditions. The research explores different catalysts and solvent effects, and demonstrates the potential for plastic degradation using atmospheric air. This study provides valuable insights into the development of more efficient and sustainable methods for plastic recycling, offering a potential solution to the significant environmental problem of plastic waste. Additionally, another article presents a novel approach for the selective degradation of polystyrene products using a photoinduced iron catalyst. The study shows that this approach is highly effective in converting polystyrene waste into valuable chemicals such as formic acid and benzoic acid. The research provides insights into the potential for chemical upcycling of common polystyrene products and waste, offering a promising avenue for reducing plastic waste. [Extracted from the article]

In the present work, we constructed a novel photoresponsive supramolecular fluorescent hydrogel through host–guest interaction between β‐cyclodextrin group in polymer 1 and azobenzene group in polymer 2. Under different external irradiations, the fluorescent hydrogel exhibited different intensities to the photo‐isomerisation of azobenzene. Light is an ideal stimulus because of its simple operation and non‐introduction of additional impurities. Therefore, this photoresponsive supramolecular hydrogel can serve as an excellent strategy for designing more practical materials. [ABSTRACT FROM AUTHOR]

A diagram which shows the synthesis of 3,3-disubstituted oxindoles from anilines nitrosated in situ is presented.

The reaction tolerates various functional groups. [ABSTRACT FROM AUTHOR]

This economic, highly regioselective acetoxylation is not influenced by electronic effects of the substituents. [ABSTRACT FROM AUTHOR]

Water compatible supramolecular polymers (WCSPs) combine aqueous compatibility with the reversibility and environmental responsiveness of supramolecular polymers. WCSPs have seen application across a number of fields, including stimuli-responsive materials, healable materials, and drug delivery, and are attracting increasing attention from the design, synthesis, and materials perspectives. In this review, we summarize the chemistry of WCSPs from 2016 to mid-2021. For the sake of discussion, we divide WCSPs into five categories based on the core supramolecular approaches at play, namely hydrogen-bonding arrays, electrostatic interactions, large π-conjugated subunits, host–guest interactions, and peptide-based systems, respectively. We discuss both synthesis and polymer structure, as well as the underlying design expectations. The goal of this overview is to deepen our understanding of the strategies that have been exploited to prepare WCSPs, as well as their properties and uses. Thus, a section devoted to potential applications is included in this review. [ABSTRACT FROM AUTHOR]

• CPs including metal–organic frameworks (MOFs) and infinite coordination polymers (ICPs). • CPs with immense feasibility in manufacturing of sensing platforms for specific applications. • The fluorescence mechanism of CPs and general fluorescence sensing mechanism were summarized. • Profiling the mechanism and advances of CPs-driven fluorescence immunoassay. • Discussing the challenges and perspectives in CPs-based fluorescence immunoassay. Fluorescence immunoassay has shown attractive potential for advancing public health due to its merits of integrating the superior specificity of immunological recognition and brilliant sensitivity of fluorescence sensors. Over the past decades, coordination polymers (CPs) have been actively pursued in the construction of fluorescence immunoassays because of their propensity for surface engineering, high compositional diversity and structural flexibility. These virtues endow CPs with immense feasibility in the target-oriented manufacturing of sensing platforms for specific applications. Despite the fact that numerous reviews on luminescent CPs or immunoassays from various perspectives have been published, a comprehensive review of CPs-based fluorescence immunoassay with sensing subjects is still lacking, and it must be organized in an all-inclusive manner with an in-depth discussion of the detection mechanisms. To better facilitate the development of this field, the fluorescence mechanism of CPs, general fluorescence sensing mechanism, and mechanism of CPs-driven fluorescence immunoassay was demystified before systematically highlighting the current state of the art in this field. Accordingly, recent applications were discussed after being classified into four categories based on the function of CPs, including direct use-, disintegration-, reaction-, and mediated-type. The objective of this review is to provide readers with an extensive overview, prospective challenges, and future perspectives for rational design of CPs-based fluorescence immunoassays. [ABSTRACT FROM AUTHOR]

Soil columns packed by Chinese loess were tested under stimulated wetting–drying cycles. The results of leaching tests showed that ACPs concentration, although changed with initial peak concentration and secondary peak concentration, eventually tended to a stable level at about 6.0 mg L−1 within 48 h. The results of wetting–drying cycle tests showed that the initial peak concentration, cumulative mass and mean size of ACPs increased with the length of drying period with the drying period. The initial peak concentration of ACPs after 90-d drying period was about nine times of that after 1 d. In addition, the release and transport of ACPs increased with the wetting–drying cycles having the same drying duration. After ten wetting–drying cycles, the initial peak concentration of ACPs for 30-d drying period increased by 35.35% and that for 15 d increased by 18.33%. The preliminary mechanisms to enhance the release and transport of ACPs include physical mechanisms of the air–water interface scouring, the shear stress of preferential flow and the collapsing pore walls by capillary pressure, and chemical mechanism of the salts dissolving of loess matrix. These findings are helpful to evaluate the risk of soil and groundwater pollution. [ABSTRACT FROM AUTHOR]

A metal-free oxidative P–S bonds coupling method for the synthesis of thiophosphates with DTBP as the oxidant is established. A wide range of functionalities are tolerated in the method. This method provides a facile way to synthesize thiophophates from readily available thiophenols/disulfides and phosphites. [ABSTRACT FROM AUTHOR]

Copper-mediated direct S–N formation using readily available starting materials via an oxygen-activated radical process has been developed. This method provides a novel and direct approach for synthesis of sulfonamides under air conditions. [ABSTRACT FROM AUTHOR]

Although nitrogen (N) transformations have been widely studied under oxic or anoxic condition, few studies have been carried out to analyze the transformation accompanied with NO 2 −-N accumulation. Particularly, the control of mixed N species in N-transformation remains unclear in an oxic-anoxic transition zone (OATZ), a unique and ubiquitous redox environment. To bridge the gap, in this study, OATZ microcosms were simulated by surface water and sediments of a shallow lake. The N-transformation processes and rates at different NH 4 +-N/NO 3 −-N ratios, and NO 2 −-N accumulations in these processes were evaluated. N-transformation process exhibited a turning point. Simultaneous nitrification and denitrification occurred in its early stage (first 10 days, dissolved oxygen (DO) ≥ 2 mg/L) and then denitrification dominated (after 10 days, DO < 2 mg/L), which were not greatly affected by the NH 4 +-N/NO 3 −-N ratio, on the contrary, the transformation rates of NH 4 +-N and NO 3 −-N were distinctly affected. The NH 4 +-N transformation rates were positively correlated with the NH 4 +-N/NO 3 −-N ratio. The highest NO 3 −-N transformation rate was observed at an NH 4 +-N/NO 3 −-N ratio of 1:1 with organic carbon/NO 3 −-N of 3.09. The NO 2 −-N accumulation, which increased with the decrease in NH 4 +-N/NO 3 −-N ratio, was also controlled by organic carbon concentration and type. The peak concentration of NO 2 −-N accumulation occurred only when the NO 3 −-N transformation rate was particularly low. Thus, NO 2 −-N accumulation may be reduced by adjusting the control parameters related to N and organic carbon sources, which enhances the theoretical insights for N-polluted aquatic ecosystem bioremediation. • Nitrogen transformation in the oxic-anoxic transition zone was investigated. • Nitrification-denitrification occurred in early days, then denitrification dominated. • NH 4 +-N/NO 3 −-N ratio controlled their transformation rates and NO 2 −-N accumulation. • NO 2 −-N accumulation peaked when NO 3 −-N transformation rate was rather low. [ABSTRACT FROM AUTHOR]

The reaction proceeds regioselectively in modest to good yields with thiophenols only. [ABSTRACT FROM AUTHOR]

A diagram is presented which shows the peroxide promotion of metal-free thiolation of phosphites through disulfides/thiophenols.