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[Objective] This study was aimed to estimate the amount of water conservation in Shaanxi Province. [Methods] The InVEST model and PLUS model were coupled to calculate the water conservation amount in Shaanxi Province from 2000 to 2020 and predict the water conservation amount under land use changes in the future in 2030. [Results] The average water conservation amount in Shaanxi Province from 2000 to 2020 was 132.25 mm, with a spatial distribution characteristic of gradually increasing water conservation from north to south. From the perspective of vegetation types, forest land was the main body of water conservation in Shaanxi Province. The average annual water conservation amount was 199.55×108 m3. From the administrative region, Ankang City had the largest water conservation amount(308.96 mm). The total amount of water source conservation in 2030 will be 285.16×108 m3 and 8.68×108 m3 less than that in 2020. [Conclusion] The water conservation amount of Shaanxi Province will show a slight downward trend from 2020 to 2030 in the future.

Objective: To discover the material substances of the numbing characteristics in Polygonatum Rhizoma. Methods: Polygonati Rhizoma from eight regions were processed by the "nine-steam-nine-bask" method, and its content changes of saponin, polyphenol and calcium oxalate crystal at different steaming times were determined. The degree change of numbing was determined by the cell hemolysis test and sensory properties, and a correlation analysis of numbing was conducted. Results: With the increase of steaming times, the contents of polyphenol and saponin in Polygonati Rhizoma from different regions were initially increased and then decreased, while the content of calcium oxalate crystal and hemolysis rate and the sensory score of numbing decreased gradually. The correlation analysis results indicated that there was a significant positive correlation (P＜0.05) or a highly significant positive correlation (P＜0.01) between the content of calcium oxalate crystal and the numbing degree. SEM results showed that the structure of calcium oxalate crystal was gradually destroyed after steaming, which coincided with the change of numbing. Conclusion: This research proves that calcium oxalate crystal may be the key substance for the numbing in Polygonatum Rhizoma, which can provide a scientific basis for the study of the numbing elimination technology of Polygonatum Rhizoma.

[Objective] Soil erosion and its associated carbon loss in an alpine meadow on the Tibetan Plateau were quantitatively analyzed in order to provide a reference for comprehensively evaluating the impact of soil erosion and for implementing effective soil and water conservation measures. [Methods] We used 137Cs tracing technology combined with the results of previous research studies to determine erosion rate and consequent carbon loss for an undisturbed alpine meadow soil on the Tibetan Plateau. [Results] The undisturbed meadow soil exhibited three distinct layers (A, B, and C) of physiochemical properties, and the distribution of 137Cs declined exponentially with increasing soil depth. The recent erosion rate of the alpine meadow soil was about 77—230 t/(km2·yr), and was estimated to result in an average annual soil organic carbon loss of not less than 4.86 t/km2. [Conclusion] Even though the overall soil erosion rate of the alpine meadow on the Tibetan Plateau was low, it’s organic carbon loss due to erosion cannot be underestimated. Both increased human activities and reduced meadow growth due to decreased soil moisture under future global warming are likely to result in further soil degradation and soil organic carbon loss in alpine meadows.

With green development advocated globally, China has firstly proposed a goal of carbon neutrality and carbon peak. Based on sustainable development theory, signal transmission theory, information asymmetry theory and stakeholder theory, this paper had used the data of 638 A-share listed companies in China from 2018 to 2020 to empirically analysed the relationship between ESG information disclosure quality and firm value. The study had concluded that the ESG quality is positively correlated with firm value. Although the impact of environment (E) and society (S) on firm value is greater than that of governance (G), the improvement of ESG split indicators will increase firm value. Finally, this paper had put forward suggestions for the firms and the government respectively.

This paper investigates whether the classroom observation protocol can be adopted in PBL studies, to explore the appropriate instruments for further observation-based studies in PBL obtain. By systematically searching and concluding previous literature, the observation protocols are given special focus, leading to the main results of this review:1) There is one formal observation tool developed for PBL settings in the area of STEM (science, technology, engineering and mathematics) education; 2) Apart from the only PBL-aimed protocol, there are other studies using tools specially designed to demonstrate teachers’ behavior and students’ engagement in real school settings; 3) Classroom observation could offer practical evidence for further exploration in a study using a mixed methodology, but formal observation tools should be adopted in these studies. In PBL studies, classroom observation could be an innovative method for further research, and more observation protocols are encouraged to be adopted or developed in the PBL obtain.

In order to express outlet deviation angle of turbomachine stator, outlet deviation angle dominantly expressed by fluid velocity distribution was derived based on equivalent moment of momentum under the condition of certain CFD simulation design parameters. On this basis, response surface function of outlet deviation angle was constructed by CFD simulation data of orthogonal experiment. The validity of the response surface function was proved by CFD simulation data of confirmatory models. An effective method is provided for calculating outlet deviation angle of turbomachine stator.