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The medium and low voltage distribution network monitoring technology cannot effectively achieve the sharing and analysis of power grid operation information at all levels, and the monitoring visualization effect is poor. To solve this problem, this study uses the VISIO (Flowchart and vector graphics software) secondary development technology to design a C# based distribution network operation online monitoring system. The system has system basic configuration management, real-time data monitoring, data query, data analysis, early warning reminder management and other functions. While running, by establishing a connection, the distribution network operation data collected by the lower computer terminal can be obtained in real time and displayed on the monitoring main page. Users only need to control the relatively simple form controls to realize the basic information configuration and online monitoring of the system. The commissioning operation results show that the system can realize remote monitoring and timely warning reminders, so that the distribution network operation data can be used in real time, and the work efficiency can be effectively improved. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office 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] The aims of this study are to explore the synergistic relationship between deep roots and soil moisture and nutrients in rainfed Medicago sativa L. and Caragana korshinskii land in the loess hilly area of southern Ningxia, and to provide scientific basis for the construction and management of artificial vegetation and the high-quality development of ecological environment in the hilly area of southern Ningxia. [Methods] The changes of soil moisture, root vertical distribution and soil N and P contents in 0—1 000 cm soil layer of 18-year-old Medicago sativa L. land and 20-year-old Caragana korshinskii forest land were analyzed by field investigation and indoor analysis. [Results]（1） The whole profile of soil below 200 cm in Medicago sativa L. land and Caragana korshinskii land was already in a dry state. The soil layers of Medicago sativa L. land and Caragana korshinskii land at extremely dry levels were 200—720 cm and 360—720 cm, respectively. The soil water storage in the depth range of 0—1 000 cm was 987.55 mm and 977.78 mm and less than that of rainfed farmland with similar topography.（2） The roots of Medicago sativa L. and Caragana korshinskii mainly concentrated in the 0—120 cm soil layer, which accounted for 45.66% and 57.54% of the total root dry weight in the 0—1 000 cm profile, and the root length density accounted for 44.45% and 67.58%.（3） The distribution of N and P nutrients in the soil of Medicago sativa L. and Caragana korshinskii lands was consistent with that of root system. The average total N content in the surface layer of 0—120 cm was 0.53 g/kg and 0.58 g/kg, respectively, which was 1.77 times and 1.87 times of the average total N content in the soil of 0—1 000 cm. The average total P content in the range of 0—120 cm was 0.51 g/kg and 0.53 g/kg, which was similar to the average total P content in the 0—1 000 cm soil layer. [Conclusion] The characteristics of soil moisture, root system and nutrient of artificial forest and grassland under the background of deep soil drying in the loess hilly area are special. In-depth study on the synergistic relationship of soil moisture, root system and nutrient in deep soil of artificial forest and grassland is helpful for the sustainable development of regional artificial vegetation and the regulation of soil carbon cycle. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development 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.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office 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.)

α-Hydroxy-3,6-diene compounds can be synthesized by the nickel-catalyzed carboalkenylation of 1,3-diene with aldehydes and alkenylzirconium reagents. 1,4-Diene structure of α-hydroxy-3,6-diene compounds is a common structural unit in a variety of bioactive molecules, which has been widely used in natural products and can be transformed into diverse polyene structures, and also can be used as a key intermediate for organic synthesis. Mass spectrometric characterization of these α-hydroxy-3,6-diene compounds presents unique ion of ［M-17]+. A series of α-hydroxy-3,6-diene compounds, including aroma-α-hydroxy-3,6-diene compounds (Ⅰ) and aliphatic α-hydroxy-3,6-diene compounds (Ⅱ), showed special ［M-17]+ during the measurement by atmospheric pressure chemical ionization time-of-flight mass spectrometry (APCI-TOF MS), which might be the fact that these compounds contained the hydroxyl groups and the dehydroxylation process were affected by the unsaturated bond. The results showed that aroma-α-hydroxy-3,6-diene compounds could directly lose one hydroxyl to form ［M-OH]+ ions due to the conjugated π bond, while aliphatic α-hydroxy-3,6-diene compounds formed the dehydration and protonation ion ［M-H2O+H]+. It was notably that aroma-α-hydroxy-3,6-diene compounds tended to form the dehydration and protonation ions if they could form conjugated structure by adding protons after dehydration. It was difficult to determine the correct fragmentation pathway of compounds only by simple inference of mass spectrometry. Combined with density functional theory (DFT) calculations, positive ion mode of high resolution mass spectrometry and tandem mass spectrometry was adopted to demonstrate the possible existence of Ⅰ and Ⅱ processes of the nine compounds. It was found that the prediction of a few compound structures did not agree with the actual pyrolysis process. The aforesaid results indicated that gas phase ions in mass spectrometry tended to generate stable structures with low electronic and thermal energies, and the position of unsaturated bonds affected the dehydroxylation process. Simple collision induced dissociation (CID) pyrolysis derivation was applicable for most α-hydroxy-3,6-diene compounds, but ionization process of some special compounds was unreasonable and needed theoretical evidence. Therefore, DFT calculation results was used to support the mass spectrometric process. These results are helpful for accurate identification of the structures of α-hydroxy-3,6-diene compounds or similar compounds, and provide theoretical basis and guidance for the ion writing specification in MS spectra and the fragmentation pathways of these compounds. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development 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.)

Copyright of Food Research & Development is the property of Food Research & Development 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.)

Copyright of Food Research & Development is the property of Food Research & Development 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.)

Copyright of Food Research & Development is the property of Food Research & Development 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.)