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Copyright of Journal of Zhengzhou University: Engineering Science is the property of Editorial Office of Journal of Zhengzhou University: Engineering Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the problems of too long transmission chain and large volume of high temperature and high pressure electricactuated valve, a novel integrated structure of high temperature and high-pressure direct drive electricactuated valve canned permanent magnet synchronous motor（DDEAV-CPMSM） was proposed. Firstly, the influence of temperature, pressure and canned sleeve parameters on the stress-strain distribution of the integrated structure were explored. Then, the electromagnetic performance under different canned sleeve parameters was compared, and the stress evaluation of the dangerous section under high temperature and high pressure was carried out. On the basis of the optimal parameters, the reinforcing ring structure was proposed, the maximum equivalent stress under different reinforcing ring sizes was compared, and the function curve of the maximum equivalent stress in the dangerous section with the thickness, width and position of the reinforcing ring was established. Finally, a high temperature and high pressure experimental platform was built to analyze the influence on the strain of the reinforcing ring. The research results show that the reinforcing ring can improve the safety factor of the canned sleeve. The average value of the measured outer diameter of the reinforcing ring is 126.172 mm, the simulated outer diameter of the reinforcing ring is 126.060 24 mm, and the relative error is 0.088%, which provides a theoretical basis for the design of the pressure-bearing structure of the integrated electric-actuated valve under high temperature and high pressure. [ABSTRACT FROM AUTHOR]

Achieving a healthy regional water balance is an important content and challenge of China′s water conservancy work, which is of great significance to ensure national water security and the sustainable and stable development of the national economy and society. This study defined the concept of a regional water balance based on a summarization of the fundamental understanding of a water balance, then its connotation was interpreted from four aspects: ① water budget balance; ② water supply- demand balance of economic society; ③ water use balance between the economy and ecology; ④ harmonious balance of human-water relationship, and three dimensions of time, space, system. This study proposed the basic principles of a regional water balance, including water balance principle, supply and demand balance principle, synergistic balance principle and harmonious balance principle. The important scientific challenges for realizing a regional water balance supported by basic principles were analyzed. The theoretical system of regional water balance was discussed in terms of two aspects of theoretical basis and basic theory. The theoretical basis includes hydrology, science of water resources, ecology, economics, sociology and other theories. The basic theory includes the spatiotemporal equilibrium theory of water resources budget, the optimal allocation theory of water resources supply and demand, the synergy theory of water use between the economy and ecology, and the human-water harmony theory. This study also discussed the prospect of applying the basic theory. The results of this study can act as a reference for future studies of the regional water balance and can provide a research framework for management of the regional water balance in the future. [ABSTRACT FROM AUTHOR]

In order to systematically analyze and accurately quantify the matching characteristics of water resources and economic and social development in prefecture-level cities, typical factors such as total water resources, water consumption, population, GDP and cultivated area were selected in this paper, and a new quantitative research idea that simultaneously applying the calculation methods of matching degree based on Gini coefficient and data sequence was proposed. Taking 10 prefecture-level cities along the Shaying River as examples, this paper quantitatively analyzed the spatial-temporal matching relationship between water resources and economic and social development from 2009 to2018. The results show that the application of the above two methods can comprehensively study the matching issue of the two systems elements from the perspective of the whole time/space and the single city/time. There are some differences in the temporal Gini coefficient among prefecture-level cities, but the matching degree of different elements is basically consistent and the results are all good. Except that the temporal matching degrees of total water resources and GDP, water consumption and GDP present a low-high-low evolution trend, the results of other elements present a fluctuation trend over time. The spatial Gini coefficient varies little on the time scale, while there are significant differences among different matching elements. The spatial matching degree is basically consistent in time and the results of some prefecture level cities are poor, especially in Zhengzhou, Nanyang and Zhumadian cities. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To establish an HPLC method for the determination of related substances of Abiraterone acetate,make an quantitative control for the impurities of Abiraterone acetate. Methods: Luna C18 column(250 mm*4.6 mm, 5 μm), the mobile phase was methanol-acetonitrile-water eluted gradiently at the rate of 1.0 m L · min-1. The rnning time was 60 min, the detection wavelengths was 220 nm, and the column temperature was 40 °C. Results: The linear ranges were 0.413 ~14.45 μg · m L-1(r=0.9996)for impurity A,0.420~14.71 μg · m L-1(r=0.9997)for impurity B, 0.398~13.98 μg · m L-1(r=0.9996)for impurity C, 0.450~15.74 μg · m L-1(r=0.9999)for impurity D, 0.394~13.79 μg · m L-1(r=0.9995)for impurity E, 0.387~13.54 μg · m L-1(r=0.9998)for impurity F, respectively. The average recoveries(n=9) of the six components were 98.14%, 99.34%, 99.65%, 100.27%, 86.21% and 97.64%,with RSDs of 2.91%,2.59%, 1.99%, 1.69%, 0.91% and 3.68%(n=9), respectively. The detection limits was 0.04, 0.09, 0.03, 0.07, 0.02, 0.12 μg · m L-1.Conclusion: This method was accurate, rapid, sensitive with high repeatability,which is more suitable for the determination of related substances of Abiraterone acetate. [ABSTRACT FROM AUTHOR]