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为充分利用油脂精炼过程中的皂脚，实现绿色油脂资源的高值化利用，以油酸钠为原料，超声辅助快速合成具有端环氧基的油酸缩水甘油酯，然后以端环氧基油酸缩水甘油酯为原料，与4-叔丁基杯\[4\]芳烃在酸性条件下发生开环反应，利用超声辅助快速合成兼具长链烷基疏水基和羟基亲水基的油脂基双亲性超分子。通过单因素实验研究了4-叔丁基杯\[4\]芳烃与端环氧基油酸缩水甘油酯物质的量比、超声时间、超声温度和超声功率对产物得率的影响，并采用FTIR和NMR进行产物结构表征。结果表明：油脂基双亲性超分子最佳合成条件为4-叔丁基杯\[4\]芳烃与端环氧基油酸缩水甘油酯物质的量比1∶ 6、超声时间150 min、超声温度50 ℃、超声功率100 W，在此条件下产物得率高达94%，该法比传统回流搅拌合成方法需要的反应时间更短，副产物更少；产物结构中含有醚氧键、羟基、长链烷基、不饱和双键和苯基，赋予超分子亲水和亲脂的双亲性能 In order to fully use the soapstock produced in the oil refining process and achieve the high-value utilization of renewable oil resources, sodium oleate was used as raw material to rapidly synthesize glycidyl oleate with epoxy terminated group assisted by ultrasound. Then the lipid-based amphiphilic supramolecules with both long chain alkyl hydrophobic group and hydroxyl hydrophilic group were rapidly synthesized by the acid catalysis ring opening reaction between glycidyl oleate with epoxy terminated group and 4-tert-butyl calix\[4\]arene using ultrasound-assisted method. The effects of molar ratio of 4-tert-butyl calix\[4\]arene to glycidyl oleate with epoxy terminated group, ultrasonic time, ultrasonic temperature and ultrasonic power on the product yield were studied by single factor experiment, and the product structure was characterized by FTIR and NMR. The results showed that the optimal synthesis conditions were obtained as follows: molar ratio of 4-tert-butyl calix\[4\]arene to glycidyl oleate with epoxy terminated group 1∶ 6, ultrasonic time 150 min, ultrasonic temperature 50 ℃, and ultrasonic power 100 W. Under the optimal conditions, the product yield was 94%. Compared with traditional reflux stirring synthesis method, ultrasound-assisted method required shorter reaction time and produced less by-products. FTIR and NMR analysis showed that the structure of the products contained aerobic ether bonds, hydroxyl groups, long alkyl chains, unsaturated double bonds and phenyl groups， which might endow supramolecules with amphipathic performance.

Copyright of Chinese Mental Health Journal / Zhongguo Xinli Weisheng Zazhi is the property of Chinese Mental Health Journal 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 Journal of Nanjing Agricultural University / Nanjuing Nongye Daxue Xuebao is the property of Journal of Nanjing Agricultural University 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 Journal of South China Agricultural University is the property of Gai Kan Bian Wei Hui 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.)

土壤是森林生态系统的重要组成部分，对森林生物多样性和生态功能的维持具有不可替代的作用.据此，本研究以千岛湖地区大陆35个样方和29个不同大小和隔离度的陆桥岛屿次生马尾松林土壤为研究对象，分析了生境片段化对土壤理化性质的影响.研究发现，大陆马尾松林土壤厚度显著高于岛屿，而其土壤最大持水量显著低于岛屿；大陆土壤的全磷(P)显著低于岛屿，而土壤有效磷(AP)和硝态氮(NO3-N)显著高于岛屿.在片段化的岛屿生境中，土壤C、N、P、NO3-N、AP随与边缘距离的增大而降低；隔离度和地形对部分土壤理化因子有影响，而岛屿面积对土壤理化性质无影响.土壤理化因子和植物群落多样性存在显著相关性.生境片段化改变了千岛湖地区马尾松林的土壤条件，而边缘效应是影响片段化生境中土壤性质空间分布的主要过程之一.通过分析片段化景观中土壤理化性质的空间分布格局及其影响因素，深化了生境片段化对土壤条件影响的认识，对于片段化森林管理措施的制定具有重要意义.

Copyright of Southwest China Journal of Agricultural Sciences is the property of Editorial Department of Southwest China Journal of Agricultural Sciences 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 Acta Agronomica Sinica is the property of Crop Science Society of China 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 Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics 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.)

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Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering 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 Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering 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 Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering 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 investigate the mediating role of alexithymia in the association between negative life events and adolescent non-suicidal self-injnry behavior ( NSSI), and the moderating role of difficulties in emotion regulation in the indirect relationship between alexithymia and adolescent NSSI. Methods: A total of 217 adolescents were selected. The Ottawa Self-Injnry Inventory ( OSI) was used to evaluate whether they have NSSI behavior, the characteristics and severity of NSSI, and the Adolescent Life Events Scale ( ASLEC) was used to evaluate the occurrence of negative life events and their impact on adolescents. Severity, Toronto Alexithymia Scale (TAS20) assesses the existence and severity of individual alexithymia, and the Difficulty in Emotion Regulation Scale (DERS) assesses the degree of difficulty in regulating emotions. Results: There was a significant positive correlation between the scores of the severity of NSSI, ASLEC, TAS and DERS in adolescents (r = 0.64, 0.61, 0.59, 0.78, 0.61, 0.64, Ps < 0.001) . The severity of NSSI in adolescents were positively associated with the ASLEC scores (β = 0.49, P <0.001). The score of TAS played a partial mediating role between the score of adolescent NSSJ and ASLEC, the mediating effect was 0. 21 (95% CI: 0.13 - 0.31, P <0.001), the mediating effect accounted for 43.1% of the total effect; the score of DERS played a moderating role in the relationship between the score of adolescent NSSI and TAS (β=0. 21, P<0.01). Conclusion: Negative life events could not only directly affect but also indirectly affect non-suicidal self-injury through alexithymia in adolescents. Difficulty in emotion regulation moderates the relationship between adolescent non-suicidal self-injury and alexithymia. [ABSTRACT FROM AUTHOR]

As one of the key technologies of artificial intelligence, image recognition has been widely used in various industries. The development of digital and intelligent water conservancy cannot be separated from the application of artificial intelligence image recognition technology. This paper firstly summarized the development and recognition process of image recognition technology, introduced the traditional image recognition technology, including statistical method, syntactic recognition method and geometric transformation method, and the image recognition technology with neural network algorithm, including depth confidence network, convolution neural network, cyclic neural network and graph convolution neural network and compared the advantages and disadvantages of the above image recognition technologies. This paper summarized the application of artificial intelligence image recognition in water conservancy industry from the four aspects of river velocity measurement, remote sensing water body recognition, water level monitoring and three-dimensional prediction. Finally, It was proposed that improving the adaptability, compatibility and recognition accuracy of technical scenarios would be the development direction of artificial intelligence image recognition in the water conservancy industry. [ABSTRACT FROM AUTHOR]

[Objective] The purpose of this study was to investigate the allelopathy of aboveground/underground extracts of sweet potato（Ipomoea batatas）, and to control weeds in farmland from the perspective of plant allelopathy. [Method] Based on seed germination rate, root length, stem length, and biomass, the allelopathic effects of four solvent extracts（petroleum ether, ethyl acetate, n-butanol alcohol, and aqueous phase） from aboveground/underground parts of sweet potato on seed germination and seedling growth of three noxious weeds（Digitaria sanguinalis, Lolium multiflorum and Bidens pilosa） were examined in the laboratory. [Result] Four extracts（petroleum ether, ethyl acetate, n-butanol alcohol, and aqueous phase） had certain inhibitory effects on seed germination rate, root length, stem length, and biomass of D. sanguinalis, L. multiflorum and B. pilosa. Petroleum ether phase and ethyl acetate phase had the strongest inhibition on seed germination and seedling growth of D. sanguinalis, L. multiflorum and B. pilosa at concentrations of 1.00-2.00 mg/mL, the inhibition rates were 40%-100% and 50-100% for seed germination, 48%-100% and 66%-100% for stem length, 65%-100% and 67%-100% for root length, and 76%-100% and 75%-100% for biomass, respectively. The lowest inhibition extracts on seed germination and seedling growth of D. sanguinalis, L. multiflorum and B. pilosa were aqueous phase and n-butanol alcohol phase that showed a ‘low-promotion and high-inhibition effect’ on root length, stem length and biomass of these three weeds. With increasing concentration of four extracts, the inhibition rates of seed germination and seedling growth of D. sanguinalis, L. multiflorum and B. pilosa were gradually increased, and the overall inhibition rates followed the order biomass>root length>stem length>seed germination. Compared to synthetical allelopathic index of four extracts on D. sanguinalis, L. multiflorum and B. pilosa, the inhibition rates of ethyl acetate phase and petroleum ether phase of underground part of sweet potato were generally higher than those of aboveground part, while the suppression rates of aqueous phase and n-butanol phase of aboveground part of sweet potato were higher than those of underground part; and B. pilosa had the strongest inhibition, followed by D. sanguinalis and L. multiflorum. [Conclusion] The results of this study confirmed that the allelochemicals with main effect were in ethyl acetate phase and petroleum ether phase of sweet potato extracts, which provided an important for further identification of allelochemicals in sweet potato germplasm resources [ABSTRACT FROM AUTHOR]

Copyright of Urban Architecture & Development is the property of Omniscient Pte. Ltd. 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 Architectural Design & Research is the property of Omniscient Pte. Ltd. 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 Acta Agronomica Sinica is the property of Crop Science Society of China 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 Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences 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 Hydrometallurgy of China is the property of Hydrometallurgy of China 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.)

Copyright of Journal of Zhejiang University (Science Edition) is the property of Journal of Zhejiang University (Science Edition) 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.)

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Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences 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.)

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Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics 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 Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences 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.)

In order to further optimize the performance of the differential pump, a multi-objective parameter optimization model was proposed for the six-blade differential pump driven by the non-circular gear with free pitch curve which had the flexible local adjustment ability. Based on the best 1∶3 order Fourier pitch curves driving the six-blade differential pump, the control vertex of the B-spline curve was designed. Three calculation models and coefficients of displacement, pulsation rate and maximum modulus without undercutting of differential pump were established. The evaluation function of comprehensive performance of differential pump was constructed by geometric average. The multi-objective optimization software was designed according to the efficiency coefficient method and the improved genetic algorithm. The Pareto solution of the free pitch curve was obtained by using the software. The results showed that the comprehensive performance of the differential pump was significantly improved after the multi-objective optimization. The displacement was increased by 2.4%, and the pulsation rate of the single pump was reduced 10.6% and the maximum modulus without undercutting increased by 30.0%. The optimization results preliminarily showed that the local optimization of free pitch curve was helpful to improve the comprehensive performance of differential pump. In order to verify the calculation results and carry out the investigation on before and after the optimization of the free pitch curve, the motor power of the differential pump test bed is 5 kW, the speed of the input shaft is 300 r/min, because the order ratio of the driving and driven gears is 1∶3, the average speed of the impeller is 100 r/min, and the cycle time of one revolution is 0.6 s. Due to the high frequency characteristics of pump source pulsation, at present, it is mainly based on the transient pressure sensor to measure and calculate the pulsation rate. The Aier AE-H high frequency pressure sensor was selected. The power supply is 24 V, the measuring range is 0-1 MPa, the measurement accuracy is ± 0.5%FS, and the signal voltage output is 0-10 V. The data acquisition device uses Altay's acquisition card and acquisition software. Refer to the input shaft speed range, and according to the sampling theorem, the sampling frequency of the acquisition card is 2 kHz. After optimization, the difference of pressure curve before and after optimization was obvious, and the peak width of pressure wave increases at the outlet of differential pump. The displacement per minute of the six-blade differential pump was increased by 3.3%, which can increase the effective volume cavity of the differential pump. According to the national standard series of modulus, the actual tooth profile modulus of the optimized non-circular gear was 2.5 mm, increased by 25.0%. According to the relevant theory of gear transmission, the increase of modulus can significantly improve the bearing capacity of the non-circular gear. The pulsation rate of differential pump was reduced by 3.1%, the impact of fluid was weakened, the leakage of pump clearance was reduced, and the volume efficiency was improved. It indicates that the comprehensive performance of six blade differential pump driven by free pitch curve non-circular gear can be effectively improved by multi-objective parameter optimization. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products 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.)