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Plastic pollution is a major environmental and health threat due to its widespread presence in ecosystems and food chains. Despite extensive research on microplastics, the detection of submicron plastics remains challenging due to their distinct physical and chemical properties and the limitations of current analytical methods. SERS has attracted significant attention in recent research as an ultra-sensitive approach for detecting nanoplastics compared to other spectroscopy techniques. In this paper, a stable, biodegradable, waste-free novel paper-based SERS substrate is developed for the rapid detection of submicron (200 nm) polystyrene (PS) particles via the controlled deposition of AuNPs onto filter paper using an atmospheric cold plasma jet printing process. The density of AuNPs increases with the number of printing passes, correlating with enhanced SERS results. The resulting SERS substrates are capable of quantifying a broad range of PS concentrations (1–500 μg mL⁻¹) using just 5 μL of analyte. The fabricated SERS substrate enables reliable quantification of PS in water, exhibiting a strong linear correlation (R² = 0.993) between SERS intensity and PS concentration, with a detection limit of 10 μg mL⁻¹ . These substrates demonstrate exceptional stability and reproducibility over a 10-week period, addressing key challenges associated with paper-based SERS substrates and making them suitable for long-term monitoring. Furthermore, analysis of tap water as a representative real-world sample demonstrates the practical applicability of the SERS substrate for environmental monitoring, revealing quantifiable levels of PS contamination. 

Abstract Molecular quantum emitters are becoming increasingly important in quantum information and communication. As a stepping stone towards a single-molecule quantum system, the collective emission from the ensemble of isolated organic chromophores, randomly and sparsely incorporated into an organometallic host crystal, is characterized by Raman and temperature-dependent photoluminescence spectroscopies. The tetracene or rubrene guest chromophores are deposited at very low densities when the ferrocene host is grown in a crystalline form, so that each of the chromophores is well isolated by its organometallic molecular neighbors. The ensemble emission of the chromophores is compared to that of the crystalline or dissolved forms to identify its unique spectral features. The enhanced quantum yield and reduced spectral linewidth with a significant blue-shift in photoluminescence suggest that ferrocene is a novel type of host matrix, maximizing the ability of the tetracene guest to act as a well-isolated quantum entity, while suppressing unwanted environmental decoherence by confining it within the ferromagnetic (organometallic) host material. 

Abstract We describe four ancient polyploidy events where the descendant taxa retain many more duplicated gene copies than has been seen in other paleopolyploidies of similar ages. Using POInT (the Polyploidy Orthology Inference Tool), we modeled the evolution of these four events, showing that they do not represent recent independent polyploidies despite the rarity of shared gene losses. We find that these events have elevated rates of interlocus gene conversion and that these gene conversion events are spatially clustered in the genomes. Regions of gene conversion also show very low synonymous divergence between the corresponding paralogous genes. We suggest that these genomes have experienced a delay in the return to a diploid state after their polyploidies. Under this hypothesis, homoeologous exchanges between the duplicated regions created by the polyploidy persist to this day, explaining the high rates of duplicate retention. Genomes with these characteristics arguably represent a new class of paleopolyploid taxa because they possess evolutionary patterns distinct from the more common and well-known paradigm of the rapid loss of many of the duplicated pairs created by polyploidy. 

Heat integration has been widely and successfully practiced for recovering thermal energy in process plants for decades. It is usually implemented through synthesizing heat exchanger networks (HENs). It is recognized that mechanical energy, another form of energy that involves pressure-driven transport of compressible fluids, can be recovered through synthesizing work exchanger networks (WENs). One type of WEN employs piston-type work exchangers, which demonstrates techno-economic attractiveness. A thermodynamic-model-based energy recovery targeting method was developed to predict the maximum amount of mechanical energy feasibly recoverable by piston-type work exchangers prior to WEN configuration generation. In this work, a heat-integrated WEN synthesis methodology embedded by the thermodynamic model is introduced, by which the maximum mechanical energy, together with thermal energy, can be cost-effectively recovered. The methodology is systematic and general, and its efficacy is demonstrated through two case studies that highlight how the proposed methodology leads to designs simpler than those reported by other researchers while also having a lower total annualized cost (TAC).