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Abstract [Objective] Sagittaria trifolia is an important horticultural and cash crop in China. Identification of genome size and analysis of karyotype are essential for genome research and molecular genetics of S. trifolia. Currently, the genome size and chromosome morphology of S. trifolia are unclear. The present study provides cytological references to S. trifolia breeding and species evolution analysis. [Methods] Using flow cytometry and fluorescence in situ hybridization, together with reference to the lysate formulation to probe configuration, the genome size of the root tips of S. trifolia variety ‘Zijinxing’ (ZJX) was identified and the chromosome morphology was analyzed. [Results] (1) The tested cecropia was a diploid plant, and the genome of ‘Zijinxing’ cecropia was about 16 Gb. (2) Using DAPI fluorescence staining, the number of chromosomes was identified to be stable, consistent with the results of telomeric fluorescence in situ hybridization. The chromosome types were middle mitotic (metacentric chromosome), near-middle mitotic (submetacentric chromosome), and proximal mitotic (acrocentric chromosome), with the most centromere was found in the proximal part, and no satellite was found. The karyotype formula was 2n=2x=22=6m+4sm+12st, belonging to the type 3B of Stebbins, with the asymmetry coefficient of 99.13. [Conclusion] The study concludes that the genome of S. trifolia is of medium size, with a highly asymmetric karyotype and a high degree of evolution.

The continuous development of new high-speed space vehicles has put forward an urgent demand for high-temperature resistant， lightweight and high-efficiency thermal insulations. Carbon aerogel not only has the excellent characteristics of low density， high porosity， high specific surface area and low thermal conductivity due to its nanoscale structure， but also has the advantages of ultra-high temperature resistance under inert atmosphere and high infrared specific extinction coefficient.Therefore， it has significant advantages in its application as a thermal insulation for the thermal protection of ultrahigh-temperature parts.In this paper， the research status of the thermal insulation properties of carbon aerogel from the aspects of aerogel density and microstructure （pore size， particle size） based on heat transfer theory were summarized firstly.Then， the researches on the preparation technologies and properties optimization of carbon aerogels for thermal insulations in recent years， which mainly included four major aspects of mechanical property enhancement，ablative resistance/oxidation resistance， low-cost， and superlight and superelastic were reviewed， and the advantages and disadvantages of the four aspects were also summarized. Finally， the future research directions of low-cost and high-performance carbon aerogel thermal insulations are proposed， and its development and application in civil and other special fields are prospected.

In order to meet the needs of large area thermal protection(≥1500 ℃)for high-speed aircraft, the high temperature resistant alumina fiber reinforced aerogel composite was used as the thermal insulation layer, and the carbon fiber fabric was used as the panel layer preform. Through the normal needle puncture process and the precursor impregnation pyrolysis process, the integrated TPS material for thermal protection was prepared, and the high temperature resistance performance tests were carried out to provide theoretical and technical support for the engineering application of materials. The results show that the integrated TPS material with good integrity and no obvious defects can be prepared by needle puncture suture technology and PIP process, and the density is only 0.6 g/cm3. When C/SiC composites are used in high-temperature oxidation environment, the oxidizing atmosphere diffuses into the material through defects such as pores and cracks, and oxidizes with carbon fibers, resulting in the degradation of composite properties. The material has excellent high temperature resistance, with mass ablation rate of 0.051 g/s and linear ablation rate of 0.077 mm/s; There is no obvious gap structure, and there is no obvious shrinkage on the whole, showing good high temperature resistance.

This paper utilizes web crawler in network text mining technology to obtain the Jiangsu garden review data on several OTAs and tourism UGC platforms, such as Baidu Tourism, Ctrip.com, and Ma’s Nest. The data preprocessing work such as text de-weighting, word frequency classification, and parameter solving is carried out on the document dataset by using the lexical algorithm, and the preprocessed text data is subjected to TF-IDF keyword extraction and LDA topic extraction. Starting from the characteristics of the cultural lineage, the intrinsic attraction elements affecting the commercial transformation of tourist attractions are explored, and taking the planning of the industrial, cultural tourism town in Ezhou as an example, the process of planning and designing from the establishment of tourism planning concepts, and thus the completion of the visual IP image, is elaborated. The tourism image perception of the four major gardens in Jiangsu is examined from both cognitive and emotional perspectives using the results of TF-IDF and LDA extraction. The results show that the trend of the frequency of each fraction of the emotion of the Humble Administrator’s Garden, Liouyuan Garden, Lion Grove, and Canglang Pavilion scenic spots is roughly the same, and the mean value of emotion is 0.758, 0.851, 0.828, and 0.845, respectively, reflecting the tourists’ average emotional perception of the individual scenic spots. This study provides new methods and ideas for promoting the integrated development of culture, commerce and tourism in small and medium-sized cities so that the culture and tourism industry can be developed sustainably.

As an emerging zero-dimensional nano crystalline porous material, porous organic cages (POCs) with soluble properties in organic solvents, are promising candidates as molecular fillers in mixed matrix membranes (MMMs). The pore structure of POCs should be adjusted to trigger efficient gas separation performance, and the interaction between filler and matrix should be optimized. In this work, ionic liquid (IL) was introduced into the molecular fillers of CC3, to construct the IL@CC3/PIM-1 membrane to effectively separate CO2 from CH4. The advantages of doping IL include: (1) narrowing the cavity size of POCs from 4.4 to 3.9 Å to enhance the diffusion selectivity, (2) strengthening the CO2 solubility to heighten the gas permeability, and (3) improving the compatibility between filler and matrix to upgrade membrane stability. After the optimization of the membrane composite, the IL@CC3/PIM-1-10% membrane possesses the CO2 permeability of 7868 Barrer and the CO2/CH4 selectivity of 73.4, which compared to the CC3/PIM-1-10% membrane, improved by 15.9% and 106.2%, respectively. Furthermore, the membrane has maintained a stable separation performance at varied temperatures and pressures during the long-term test. The proposed method offers an efficient way to improve the performance of POCs-based MMMs in gas separation. [ABSTRACT FROM AUTHOR]