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In this work, blends of monomer‐cast polyamide 6 (MCPA6) and polyurethane (TPU) were prepared by in situ anionic ring‐opening polymerization using caprolactam as the monomer and sodium hydroxide (NaOH) as the initiator. TPU degraded under weakly alkaline conditions to form an isocyanate group, which acted as a macromolecule activator to initiate the growth of the MCPA6 chain, and the formation of TPU‐co‐MCPA6 copolymer in this system, which improves the compatibility between MCPA6 and TPU. The MCPA6/TPU blends were tested for conversion, viscosity, and mechanical properties, and their structures and thermal properties were analyzed and evaluated by characterization techniques such as Fourier transform infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. [ABSTRACT FROM AUTHOR]

The infrared spectra of common biodegradable plastics were first collected using attenuated total reflection infrared spectroscopy, and their characteristic functional groups were labeled. A blend of biodegradable plastic and non-degradable plastic was prepared through melt blending and solution blending. The results indicated that a rapid detection method based on infrared spectroscopy was efficient and accurate in the analysis of biodegradable plastics. This study provides useful references for promoting the development of biodegradable plastics and the treatment of plastic pollution. [ABSTRACT FROM AUTHOR]

Post‐stroke depression is a common complication that imposes significant burdens and challenges on patients. The occurrence of depression is often associated with frontal lobe hemorrhage, however, current understanding of the underlying mechanisms remains limited. Here, the pathogenic mechanisms associated with the circuitry connectivity, electrophysiological alterations, and molecular characteristics are investigated related to the frontal lobe in adult male mice following unilateral injection of blood in the medial prefrontal cortex (mPFC). It is demonstrated that depression is a specific neurological complication in the unilateral hematoma model of the mPFC, and the ventral tegmental area (VTA) shows a higher percentage of connectivity disruption compared to the lateral habenula (LHb) and striatum (STR). Additionally, long‐range projections originating from the frontal lobe demonstrate higher damage percentages within the connections between each region and the mPFC. mPFC neurons reveal reduced neuronal excitability and altered synaptic communication. Furthermore, transcriptomic analysis identifies the involvement of the Janus Kinase‐Signal Transducer and Activator of Transcription (JAK‐STAT) signaling pathway, and targeting the JAK‐STAT pathway significantly alleviates the severity of depressive symptoms. These findings improve the understanding of post‐hemorrhagic depression and may guide the development of efficient treatments. [ABSTRACT FROM AUTHOR]

The polymer/nano-inorganics composite microsphere possesses excellent application prospects, but it is difficult to resolve the problem of the aggregation of nano-inorganic particles in polymer and the affinity between inorganics and polymer matrix. In this study, the preparation and characterization of polystyrene (PS)/ethylene vinyl acetate copolymer (EVA)/CaCO3 microspheres fabricated via a novel phase inversion emulsion process are described. By this one-pot method, the PS/EVA/CaCO3 microspheres are obtained by firstly converting styrene monomer containing EVA and nano CaCO3 into droplets dispersed in water with help of emulsifiers and a following polymerization. Because the inorganic nanoparticles are ultrasonically dispersed in liquid monomer mixture before the polymerization, the aggregation of nano-inorganic particles could be prevented to a great extent. The EVA is designed to enhance toughness of polystyrene matrix and increase the affinity between polymer and inorganic particles. The morphological structure of PS/EVA/CaCO3 microspheres is that nano CaCO3 particles are embedded both in the interior and on the surface of the microspheres. The micro-sized PS/EVA/CaCO3 microspheres showed a significantly improved mechanical property and a better heat resistance. This technique also offers the possibility for fabricating many kinds of new and useful polymer/inorganic microspheres with tailored performance by using special monomers and inorganic particles. [ABSTRACT FROM AUTHOR]

Based on tropical cyclone yearbook data from 1949 to 2006, climate characteristics, such as interdecadal variation, period of tropical cyclone frequency, rainstorm and strong wind, intensity characteristics, were analyzed. Main results were as follows: tropical cyclone affecting Shandong Province was mainly from the last ten-day of July to the last ten-day of August, and its interdecadal variation was obvious. The marked periodic variation of every 2. 4 and 5 years was found according to power spectrum analysis. It showed obvious weakening tendency about tropical cyclone's intensity by using Kendall test. It also showed that August was the strongest month among a year for rainstorm frequency and intensity, and flood disaster was more easily/ to occur during this month. It was distinct for frequency's interdecadal variation of tropical cyclone causing rainstorm and strong wind. Marked period was existed about annual average precipitation and strong wind. At the same time, the cause of the variation was discussed. [ABSTRACT FROM AUTHOR]

The main objective of this article was to study the capillary effects during the impregnation of polypropylene resin in the jute fiber mats. The static equilibrium contact angles between polypropylene matrix and fibers were measured and the dynamic impregnation of matrix in the fiber mats was researched in detail. The results show that the static contact angles are clam-shell shape. The capillary effects present little values in the dynamic impregnation. The preparation for low void composites should be performed below the critical resin flow velocity of 0.13 µm/s for polypropylene resin and 0.21 µm/s for polypropylene/maleated polypropylene blend resin, respectively. [ABSTRACT FROM AUTHOR]

In this article, the microstructures of sisal fiber composites were analyzed. The porous structure of sisal fiber, crystalline morphology of matrix and fiber distribution in composites were characterized by Voronoi diagram. The tensile properties of composites were also measured. The results show that the maleated polypropylene compatibilizer can accelerate the formation of transcrystalline interface between fibers and matrix. Improvement of interface adhesion and reduction of fiber polarity can lead to better fiber distribution in the matrix. The tensile moduli of composites are related to the degree of fiber distribution. [ABSTRACT FROM AUTHOR]