Preparation of fluorescent thermoplastic polyurethane microcellular foam films blown by supercritical CO2

Preparation of fluorescent thermoplastic polyurethane microcellular foam films blown by supercritical CO

Improved expansion ratio and heat resistance of microcellular poly(L-lactide) foam via in-situ formation of stereocomplex crystallites

It is critical to broaden the applications of poly(L-lactic acid) foams by improving heat resistance properties. The stereocomplex crystallites that are formed by melt blending of poly(L-lactic acid)/polylactide possess high melting point of about 220? and thus exhibit high heat resistance; therefore, the introduction of stereocomplex crystallites tends to improve the thermal stability of poly(lactic acid) foam. Unfortunately, using the solid-state foaming method, it was found that the expansion ratio of the obtained poly(lactic acid) foams was compromised with the value of 1.7 times once the stereocomplex crystallites were formed during the sample saturation stage. In this study, by applying a high compression molding temperature of 230?, the as-prepared poly(L-lactic acid) and poly(L-lactic acid)/polylactide blends were amorphous. After being CO2 saturated at a mild condition, the specimens were foamed at 90-160?. The wide-angle X-ray diffraction profiles presented that the stereocomplex crystallites and PLA homocrystals were in-situ generated during the foaming process. It is observed that the in-situ formed stereocomplex crystallites could act as the physical cross-linking agent to stabilize the nucleated bubbles and suppress cell coalescence, resulting in the increased expansion ratio (with value of about 23.6-25.6 times) and cell density, especially at high foaming temperatures and extended foaming time. Furthermore, the in-situ formed stereocomplex crystallites during the foaming increased the heat resistance performance of poly(L-lactic acid) foams. This novel crystallization control method helps us to find a balance point in preparing poly(L-lactic acid) foam with high expansion ratio, well-defined cell structure and high heat resistance performance

Genome-wide identification of flowering Chinese cabbage BPC family genes and BcBPC9 functional analysis in Cd stress tolerance

Flowering Chinese cabbage is an important vegetable crop widely cultivated in southern China. However, flowering Chinese cabbage plants are susceptible to diverse environmental influences that mainly affect crop quality and production. The BASIC PENTACYSTEINE (BPC) transcription factor is an essential regulator of plant development and abiotic stress responses. However, the function and molecular mechanism of the BPC family genes in flowering Chinese cabbage remain unclear. This study aimed to investigate the molecular mechanisms of the BcBPC gene in abiotic stress tolerance. In flowering Chinese cabbage, 12 BcBPC family genes have been identified and found to be unequally distributed on eight chromosomes. Comprehensive analyses of BcBPC gene structure, motif analysis, cis-regulatory elements, and subcellular localization were performed. BcBPC genes were classified into three groups based on their sequence composition, phylogenetic relationships, and conserved domains, which were highly linked to those of other species. BcBPC family gene promoter consists 69.92% stress-responsive, 32.38% hormone-responsive, and 5.30%, related to growth- and biological process-responsive cis-regulatory elements. Subsequent qRT-PCR results showed that BcBPC genes were highly upregulated under abiotic stress, especially under NaCl and Cd stress. The overexpression of BcBPC9 increases Cd stress tolerance in yeast. BcBPC9 is located in the nucleus, but moves to the cell wall when exposed to Cd stress. BcBPC9 transient overexpression tobacco were improved growth and upregulated the antioxidant enzymes genes expression when exposed to Cd stress. These findings facilitate further investigation of the functional and molecular characteristics of BcBPC9 in response to abiotic stress. The outcomes of this study provide a crucial foundation for future research on improving plant growth and protecting vegetable production

Optimal energy scheduling of grid-connected microgrids with demand side response considering uncertainty

The benefits of more comprehensive energy use and promotion of renewable energy (RE) consumption enable large-scale microgrid deployment. However, the uncertainty of renewable energy sources and the diversity of load types pose a threat to the microgrid's stability. Recently, energy scheduling optimization for microgrids (MGs) has been primarily based on ideal models, but incorporating as many real-world characteristics as feasible can improve the reliability of the optimization outcome. This paper provides a multi-stage methodology for solving the energy management optimization (EMO) problem of MG under uncertainty considering carbon trading market and demand side response (DSR). To begin, scenario analysis method was used to address the uncertainty associated with RE in MG, and four typical scenarios of renewable energy were generated. Then, the flexible configuration and operational constraints of each power source in MG are dealt with under the premise of considering the carbon trading market. The third stage involved merging the characteristics of various load types and analyzing the response impacts of different percentage residential and industrial loads, respectively, using the price-based and load-transfer-based DSR approaches. Finally, quantum particle swarm optimization (QPSO) algorithm was used to obtain the optimal solution. The acquired results demonstrate the efficacy of the proposed multi-stage energy optimization framework, and support the following two conclusions: 1) The carbon trading market policy contributes to the reduction of carbon emissions and fossil fuel consumption. 2) A high load participation rate in DSR can increase MG operation economics by up to 27.48% compared to not considering DSR