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In this study, a 4-(hydroxymethyl)-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane 1-oxide (PEPA)-functionalized acrylate monomer, PEPAA, is designed and utilized for the synthesis of macromolecular flame retardants poly(PEPAA-co-AM) with varying PEPAA/AM ratio through copolymerization with acrylamide (AM). The poly(PEPAA-co-AM) is then incorporated into polypropylene (PP) to prepare PP/poly(PEPAA-co-AM) composites. The flame retardant effect of poly(PEPAA-co-AM) on PP is investigated using cone calorimetric test (CCT), and compared with that of PEPAA homopolymer (P-PEPAA), AM homopolymer (PAM), and blends of P-PEPAA/PAM. The results demonstrate that, in comparison with P-PEPAA, PAM, and blends of P-PEPAA/PAM, the incorporation of poly(PEPAA-co-AM) significantly enhances the flame retardancy of PP. Notably, the best flame retardancy is achieved when the ratio of PEPAA/AM copolymerization in poly(PEPAA-co-AM) is 2/8. The morphology and composition of residual chars from combustion are analyzed using SEM-EDS while the residual graphitization degree is examined through Raman spectroscopy. Additionally, TG-FTIR-MS is utilized to investigate the pyrolysis products in gas phase during thermal decomposition of poly(PEPAA-co-AM). Based on these experimental results, a flame retardant mechanism for poly(PEPAA-co-AM) is proposed. The PP/poly(PEPAA-co-AM) composites not only retain the excellent processing properties of pure PP but also exhibit enhanced mechanical properties., (© 2024 Wiley‐VCH GmbH.)

Lhx3 is a LIM-homeodomain transcription factor that affects body size in mammals by regulating the secretion of pituitary hormones. Akita, Shiba Inu, and Mame Shiba Inu dogs are Japanese native dog breeds that have different body sizes. To determine whether Lhx3 plays a role in the differing body sizes of these three dog breeds, we sequenced the Lhx3 gene in the three breeds, which led to the identification of an SNP in codon 280 (S280N) associated with body size. The allele frequency at this SNP differed significantly between the large Akita and the two kinds of smaller Shiba dogs. To validate the function of this SNP on body size, we introduced this change into the Lhx3 gene of mice. Homozygous mutant mice (S279N +/+ ) were found to have significantly increased body lengths and weights compared to heterozygous mutant (S279N +/- ) and wild-type (S279N -/- ) mice several weeks after weaning. These results demonstrate that a nonsynonymous substitution in Lhx3 plays an important role in regulating body size in mammals.

An impact polypropylene copolymer (IPC), composed of polypropylene (PP) and ethylene-propylene copolymer (EPC), was synthesized through two-stage in-reactor polymerization. A systematic investigation of the crystalline structure, thermal behavior, morphology, and tensile properties of the IPC extruded cast film was conducted. Specifically, the morphology of EPC was obtained by confocal Raman imaging by depicting the spatial distribution of the Raman band located at 1064 cm -1 . The EPC phase exhibits fibrous morphology with the long axis aligning along the machine direction (MD). A three-dimensional (3D) heterogeneous structure of the IPC cast film obtained by confocal Raman imaging confirms that the fibrous EPC phase is dispersed in a 3D framework of the PP matrix. The mesomorphic phase in the as-prepared cast film transforms to a stable α-form crystal after annealing at 130 °C, which improves the yield strength but decreases the elongation of the cast film. The WAXD and SAXS results indicate that there is no obvious orientation of the crystallites. Thus, the anisotropy of tensile properties in the MD and transverse directions is closely related to the anisotropic phase morphology at the micrometer scale. The results reveal that the mechanical performances of IPC films are determined by the crystalline structure of the PP matrix and the morphology.

Continuous flow synthesis is pivotal in dye production to address batch-to-batch variations. However, synthesizing water-insoluble dyes in an aqueous system poses a challenge that can lead to clogging. This study successfully achieved the safe and efficient synthesis of azo dyes by selecting and optimizing flow reactor modules for different reaction types in the two-step reaction and implementing cascade cooperation. Integrating continuous flow microreactor with continuous stirred tank reactor (CSTR) enabled the continuous flow synthesis of Sudan Yellow 3G without introducing water-soluble functional groups or using organic solvents to enhance solubility. Optimizing conditions (acidity/alkalinity, temperature, residence time) within the initial modular continuous flow reactor resulted in a remarkable 99.5% isolated yield, 98.6 % purity, and a production rate of 2.90 g h -1 . Scaling-up based on different reactor module characteristics further increased the production rate to 74.4 g h -1 while maintaining high yield and purity. The construction of this small 3D-printing modular cascaded reactor and process scaling-up provide technical support for continuous flow synthesis of water-insoluble dyes, particularly high-market-share azo dyes. Moreover, this versatile methodology proves applicable to continuous flow processes involving various homogeneous and heterogeneous reaction cascades., (© 2024 Wiley-VCH GmbH.)

Fog harvesting is considered a promising freshwater collection strategy for overcoming water scarcity, because of its environmental friendliness and strong sustainability. Typically, fogging occurs briefly at night and in the early morning in most arid and semiarid regions. However, studies on water collection from short-term fog are scarce. Herein, we developed a patterned surface with highly hydrophilic interconnected microchannels on a superhydrophobic surface to improve droplet convergence driven by the Young-Laplace pressure difference. With a rationally designed surface structure, the optimized water collection rate from mild fog could reach up to 67.31 g m -2 h -1 (6.731 mg cm -2 h -1 ) in 6 h; this value was over 130% higher than that observed on the pristine surface. The patterned surface with interconnected microchannels significantly shortened the startup time, which was counted from the fog contact to the first droplet falling from the fog-harvesting surface. The patterned surface was also facilely prepared via a controllable strategy combining laser ablation and chemical vapor deposition. The results obtained in outdoor environments indicate that the rationally designed surface has the potential for short-term fog harvesting. This work can be considered as a meaningful attempt to address the practical issues encountered in fog-harvesting research.

The Diels-Alder (D-A) reaction between furan and maleimide is a thermally reversible reaction that has become a vital chemical technique for designing polymer structures and functions. The kinetics of this reaction, particularly in polymer bulk states, have significant practical implications. In this study, we investigated the feasibility of utilizing infrared spectroscopy to measure the D-A reaction kinetics in bulk-state polymer. Specifically, we synthesized furan-functionalized polystyrene and added a maleimide small-molecule compound to form a D-A adduct. The intensity of the characteristic absorption peak of the D-A adduct was quantitatively measured by infrared spectroscopy, and the dependence of conversion of the D-A reaction on time was obtained at different temperatures. Subsequently, the D-A reaction apparent kinetic coefficient k app and the Arrhenius activation energy E a,D-A were calculated. These results were compared with those determined from 1 H-NMR in the polymer solution states.

Due to the rapid development of the miniaturization and portability of electronic devices, the demand for polymer composites with high thermal conductivity and mechanical flexibility has significantly increased. A carbon nanotube (CNT)-graphene (Gr)/polydimethylsiloxane (PDMS) composite with excellent thermal conductivity and mechanical flexibility is prepared by ultrasonic-assisted forced infiltration (UAFI). When the mass ratio of CNT and Gr reaches 3:1, the thermal conductivity of the CNT-Gr(3:1)/PDMS composite is 4.641 W/(m·K), which is 1619% higher than that of a pure PDMS matrix. In addition, the CNT-Gr(3:1)/PDMS composite also has excellent mechanical properties. The tensile strength and elongation at break of CNT-Gr(3:1)/PDMS composites are 3.29 MPa and 29.40%, respectively. The CNT-Gr/PDMS composite also shows good performance in terms of electromagnetic shielding and thermal stability. The PDMS composites have great potential in the thermal management of electronic devices.

The integral catalytic impeller can simultaneously improve reaction efficiency and avoid the problem of catalyst separation, which has great potential in applying heterogeneous catalysis. This paper introduced a strategy of combining electroless copper plating with 3D printing technology to construct a pluggable copper-based integral catalytic agitating impeller (Cu-ICAI) and applied it to the catalytic reduction of 4-nitrophenol (4-NP). The obtained Cu-ICAI exhibits very excellent catalytic activity. The 4-NP conversion rate reaches almost 100% within 90 s. Furthermore, the Cu-ICAI can be easily pulled out from the reactor to be repeatedly used more than 15 times with high performance. Energy-dispersive spectrometry, X-ray diffraction, and X-ray photoelectron spectroscopy characterizations show that the catalyst obtained by electroless copper plating is a ternary Cu-Cu 2 O-CuO composite catalyst, which is conducive to the electron transfer process. This low-cost, facile, and versatile strategy, combining electroless plating and 3D printing, may provide a new idea for the preparation of the integral impeller with other metal catalytic activities., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Volatile organic compounds (VOCs) from polypropylene (PP) seriously restricts the application of PP in an automotive field. Herein, the traceability of VOCs from PP resins during manufacturing process and accelerated photoaging degradation was clarified on basis of an accurate characterization method of key VOCs. The influence of PP structures on changing the accelerated photoaging degradation on the VOCs was systematic. The VOCs were identified by means of Gas chromatography (GC) coupled with both a hydrogen flame ion detector (FID) and a mass spectrometry detector (MSD). Results showed that both the molecular structure of PP and the manufacturing process affected the species and contents of VOCs. In addition, the photoaging degradation of PP resulted in a large number of new emerged volatile carbonyl compounds. Our work proposed a possible VOC formation mechanism during the manufacturing and photoaging process. VOCs from PP resins were originated from oligomers and chain random scission during thermomechanical degradation. However, β scission of alkoxy radical and Norrish tape I reactions of ketones via intermediate transition were probably the main VOCs formation routes towards PP during photoaging degradation. This work could provide scientific knowledge on both the accurate traceability of VOCs emissions and new technology for development of low-VOCs PP composites for vehicle.

Studies on distribution dynamics of waterbirds and the relation with hydrological changes are essential components of ecological researches. East Dongting Lake is a Ramsar site and especially important wintering ground for herbivorous geese along the East Asian-Australasian Flyway. In this paper, based on annual (2008/09-2016/17) waterbird census data, we investigated the spatial-temporal distributions of three herbivorous goose species (Lesser White-fronted Goose Anser erythropus, Bean Goose Anser fabalis, and Greater White-fronted Goose Anser albifrons) within East Dongting Lake, and analyzed their distribution dynamics (denoted by percentage similarity index, PSI) relative to variations in hydrological regime. The results demonstrated that the distribution of the globally vulnerable Lesser White-fronted Geese changed obviously between years, whereas that of Bean Geese was more stable. Greater White-fronted Geese suffered drastic distribution variation during the study period. The PSI of Lesser White-fronted Geese was negatively correlated with between-year difference in water recession time and mean water level in October, whereas no obvious trend was found in Bean Geese. The Normalized Difference Vegetation Index (NDVI) was applied to detect changes in food resources of the geese, and significant correlations were also found between NDVI and hydrological factors. It was inferred that the variations in hydrological regime affected the annual distribution dynamics of Lesser White-fronted Geese by changing food conditions; whereas the effect on Bean Geese were not reflected in this study. Species traits may explain the differences in distribution dynamics among the three goose species. It was speculated that Lesser White-fronted Geese might be more sensitive to habitat change, whereas Bean Geese were more resilient. We suggested that regulating hydrological regime was crucial in management works. Our study could offer scientific information for species conservation in the context of habitat changes in East Dongting Lake wetland and provide potential insights into habitat management in this area., (Copyright © 2018 Elsevier B.V. All rights reserved.)