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火灾下混凝土框架结构力学性能研究

沈阳建筑大学学报（自然科学版） 2021年第1期37卷 77-85页

作者：宋岩升潘勇旭赵刚沈阳建筑大学土木工程学院辽宁沈阳110168

目的模拟高层混凝土框架结构的火灾全过程并研究火灾后框架结构及构件力学性能,为此类结构火灾后的损伤评估与加固方案设计提供参考依据。方法利用火灾模拟软件PyroSim对某高层宿舍楼首层火灾进行模拟,研究室内火灾下温度场分布,应用ABA... 详细信息

目的模拟高层混凝土框架结构的火灾全过程并研究火灾后框架结构及构件力学性能,为此类结构火灾后的损伤评估与加固方案设计提供参考依据。方法利用火灾模拟软件PyroSim对某高层宿舍楼首层火灾进行模拟,研究室内火灾下温度场分布,应用ABAQUS有限元软件分析火灾下结构和构件的温度场,以及静、动力作用下结构和构件的变形及内力。结果通风条件对室内火灾温度场影响较大,实际升温曲线与ISO834标准升温曲线结果存在一定差异;梁、柱构件截面温度场分布不均匀,绝大部分面积温度未超过500℃,节点核心区的温度较周围的梁段和柱段偏低,受火后梁CD、柱C和柱D最大极限承载力剩余约为35.4%、26.4%和62.7%,结构尚余部分承载力仍可继续使用;受火后框架首层在地震作用下层间位移角明显增大,2~8层增幅逐渐递减,首层结构在EI-Centro波、唐山波作用下层间位移角超出规范限值约16.5%、48.9%。结论建议用PyroSim火灾模拟软件得到的升温曲线进行结构分析;火灾后应重点检测过火区域构件力学性能,计算首层层间位移角变化,据此制定加固方案。

关键词：混凝土框架火灾模拟有限元分析升温曲线高层建筑

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10kV配电网线路故障防范探析

电子测试 2017年第7X期28卷 77-77,67页

作者：潘勇旭中铁建电气化局集团南方工程有限公司湖北武汉430000

在现代配电网之中,10kV配电网线路故障不但会影响供电效率,同时也会直接威胁到配电网的运行的安全和稳定。所以,探讨10kV配电网线路常见的故障,及时做好故障的消除才能够确保供电的可靠性。

关键词： 10kV配电网线路故障

基于短时傅里叶变换的电子式电流互感器在线校正研究

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自动化应用 2024年第21期65卷 118-120页

作者：潘勇旭中铁建电气化局集团南方工程有限公司湖北武汉430074

受环境温度、电磁干扰等因素的影响,电子式电流互感器在实际运行中会产生误差,为此,研究基于短时傅里叶变换的电子式电流互感器在线校正方法。通过短时傅里叶变换分析电子式电流互感器输出信号,评估出互感器测量误差,根据互感器误差频... 详细信息

受环境温度、电磁干扰等因素的影响,电子式电流互感器在实际运行中会产生误差,为此,研究基于短时傅里叶变换的电子式电流互感器在线校正方法。通过短时傅里叶变换分析电子式电流互感器输出信号,评估出互感器测量误差,根据互感器误差频谱图自动校正输出信号的幅值与相位,实现电子式电流互感器误差的在线校正。结果表明,经过设计方法校正后,电子式电流互感器的幅值与相角测量误差显著减小,该方法可以有效提升互感器测量精度。

关键词：短时傅里叶变换电子式电流互感器互感器误差误差校正在线校正

Effects of citrus tree-shape and spraying height of small unmanned aerial vehicle on droplet distribution

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International Journal of Agricultural and Biological Engineering 2016年第4期9卷 45-52页

作者： Zhang pan Deng Lie Lyu Qiang He Shaolan Yi Shilai Liu Yande Yu yongxu pan Haiyang Citrus Research Institute Southwest UniversityBeibeiChongqing 400712China Institute of Optics-Electrics Technology and Application East China Jiaotong UniversityNanchang 330013China College of Plant Protection Southwest UniversityBeibeiChongqing 400715China Zhuhai Green Guards Aviation Plant Protection Technology Co.Ltd. Zhuhai 519085GuangdongChina

In order to explore the droplet penetration of spraying with unmanned aerial vehicle(UAV)on citrus trees with different shapes,the tests were carried out at different working *** material was five years old Cocktail grapefruit(Citrus paradisi ***)grafted on Trafoliata(Poncirus trifoliata ***.)and the type of UAV sprayer used was the 3W-LWS-Q60S.A solution of 300 times Ponceau 2R diluents liquid instead of pesticide was used for citrus fields spraying and the droplets were collected by paper *** deposition parameters were extracted and analyzed using digital image processing after scanning the *** results showed that:1)For the trees with round head shape canopy,the droplet depositions of the upper,middle and lower layers had a significant difference at 0.05 *** droplet deposition had the best effect when the working height was 1.0 m,where the average droplet deposition densities were 39.97 droplets/cm2 and the average droplet size was 0.30 mm,but the droplet coverage(3.19%)was lower than that at the working height of 1.5 m(4.27%).2)Under three different working heights of UAV,the tree with open center shape can obtain higher droplet deposition density at all three layers than that with the round head shape *** was especially prominent when the working height was 1.0 m,as the middle layer increased by 49.92%.However,the higher range of droplet deposition density meant larger fluctuation and dispersion.3)The open center shape canopy and the 1.0 m working height obviously improved the droplet coverage rate and droplet density in the citrus *** these parameters of open center shape citrus tree,there was no obvious difference in the front and rear direction,but in the left and middle part of the tree crown,the difference reached a 0.05 significant *** droplet deposition characteristics and the spray uniformity,the UAV performed better when working on open center shape plants at a 1.0 m working height.

关键词： citrus tree shape unmanned aerial vehicle(UAV) droplet deposition

Impacts of different feeding modes on the gonadal development, total edible yield, and nutritional composition of male Chinese mitten crab (Eriocheir sinensis)

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Aquaculture and Fisheries 2020年第6期5卷 300-307页

作者： Jie pan Renfu Wu Xugan Wu Xiaowen Long Xichang Wang yongxu Cheng Centre for Research on Environmental Ecology and Fish Nutrition of Ministry of Agriculture and Rural Affairs Shanghai Ocean UniversityShanghai201306China College of Food Science and Technology Shanghai Ocean UniversityShanghaiLingang New City201306China Shanghai Engineering Research Center of Aquaculture Shanghai Ocean UniversityShanghai201306China Shanghai Collaborative Innovation Center for Aquatic Animal Genetics and Breeding Shanghai Ocean UniversityShanghai201306China

This study analyzed the tissue indices,proximate composition,fatty acid and amino acid composition of edible tissues of male *** under three feeding modes(formulated diets(FD),natural diets(ND),and traditional diets(TD)).The results showed that different feeding modes had no impacts on the overall gonadal development,as no significant difference was found in gonadsomatic index among three *** edible yield,three modes all had similar levels of the meat yield,hepatosomatic index,and total edible *** different feeding modes did not affect the individual edible yield and gonadal development,significant differences were detected in the nutritional composition of males from three *** proximate composition,significant differences were found in the total lipids of gonads and the carbohydrate of hepatopancreas and *** fatty acids,crabs from ND had a higher proportion of monounsaturated fatty *** gonads and hepatopancreas,FD had a higher proportion of long-chain polyunsaturated fatty *** amino acids,FD had higher amino acid contents,while ND had the *** tryptophan,the essential amino acids scores of the meat were all greater than *** there was no significant difference on meat quality and meat yields between three feeding modes,this study suggests that the formulated diet could replace the natural diet and traditional diet towards sustainable crab farming in future.

关键词： Eriocheir sinensis Feeding modes Edible yield Gonadal development

Effects of microbe-derived antioxidants on growth,digestive and aminotransferase activities,and antioxidant capacities in the hepatopancreas of Eriocheir sinensis under ammonia nitrogen stress

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Aquaculture and Fisheries 2024年第6期9卷 957-966页

作者： Aoya Shi Huan Ma Xingliang Shi Wenquan Zhou Wangjun pan Yameng Song Qing Chen Xiaowen Yu Chao Niu Yingfei Yang yongxu Cheng Xiaozhen Yang National Demonstration Center for Experimental Fisheries Science Education Shanghai Ocean UniversityShanghai201306China Key Laboratory of Freshwater Aquatic Genetic Resources Ministry of AgricultureShanghai Ocean UniversityShanghai201306China Engineering Research Center of Aquaculture Shanghai Ocean UniversityShanghai201306China Changzhou Jintan District Aquatic Technology Promotion Center 213299China Shandong Jingming Marine Technology Co. LTD257091China

This study evaluated the effects of feeding a microbial-derived antioxidant diet(MA)for 56 days on the growth performance of Eriocheir sinensis,as well as on digestive and metabolic enzyme activity and antioxidant capacity under ammonia stress(400 mg/L ammonia nitrogen for 48 h).The weight gain at 28d and the specific growth rate at 56ds for crabs in the MA group were significantly higher than those in the control diet(C)group(ppancreas in the MA group was significantly improved(ppancreas in the(MA_A)group(ppancreas caused by ammonia nitrogen toxicity could also significantly be improved by MA fed in the(MA_A)group(ppancreas,promote growth,and improve the ability to resist ammonia nitrogen stress for ***.

关键词： Eriocheir sinensis Microbial-derived antioxidant Growth Ammonia nitrogen

Non-destructive analysis on the plumpness of hepatopancreas and gonad tissues in live Eriocheir sinensis using low-field 1H magnetic resonance imaging

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Non-destructive analysis on the plumpness of hepatopancreas ...

中国食品科学技术学会第十三届年会

作者： Zhang Hongcai Yan Shiqiang Song Dandan Zhao Yong Cheng yongxu pan Yingjie Wu Xugan Zhang Weijia Laboratory of Aquatic Products Quality & Safety Risk Assessment(Shanghai) at China Ministry of Agriculture College of Food Science and TechnologyShanghai Ocean University Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources at China Ministry of Education College of Fisheries and Life ScienceShanghai Ocean University Shanghai Niumag Electronic Technology Co. LTD

The hepatopancreas and gonad tissues of Chinese mitten crabs(Eriocheir sinensis) are beloved raw food materials in Asian countries because its excellent taste and high nutritional ***,the plumpness of hepatopancreas and gonad tissues denotes the grading scale and the commercial value of a whole *** *** this work,a low-field T-weighted ’ H magnetic resonance imaging(LF-MRI) technique is developed to non-destructively analyze the plumpness of hepatopancreas and gonad in live *** male and female *** were characterized by LF-MRI *** results showed that the plumpness and total lipid content in mature *** were significandy higher than that of immature *** conclusion,the H LF-MRI scanning technology was successfully developed to accurately discriminate the development of ***’ s hepatopancreas and gonad organs in a non-destructive manner,therefore indicating its application in grading commercial live crabs or advising crab fanners on breeding and fattening process.

关键词： eriocheir sinensis magnetic resonance imaging lipid content calculation aquatic food non-destructive analysis

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双碳发展对我国的影响及应对策略

技术经济 2021年第9期40卷 172-180页

作者：潘小海伍勇旭李东中国国际工程咨询有限公司北京100048 中国国际工程咨询有限公司业务发展部北京100048 中国国际工程咨询有限公司研究中心北京100048

近年来二氧化碳排放持续快速增长,全球气候变暖已成不争事实。国际社会为共同应对气候变化做出了积极努力,截至2020年底,全球已有40余个国家和经济体正式宣布了碳中和目标。我国化石能源消费和二氧化碳排放持续增长,占全球比重逐步升高... 详细信息

近年来二氧化碳排放持续快速增长,全球气候变暖已成不争事实。国际社会为共同应对气候变化做出了积极努力,截至2020年底,全球已有40余个国家和经济体正式宣布了碳中和目标。我国化石能源消费和二氧化碳排放持续增长,占全球比重逐步升高,为提升发展质量,彰显大国责任,需要积极科学推动碳达峰碳中和工作。同时,双碳发展将对我国经济社会产生重要深远影响,能源结构、产业布局将发生深刻调整。面对重大机遇挑战,应以战略性思维统筹推进双碳工作,找准发力点,分阶段稳步实施,努力实现经济社会高质低碳创新发展。

关键词：双碳发展全球变暖能源消费二氧化碳排放应对策略

基于地标点几何形态测量法区分不同水系野生中华绒螯蟹

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中国水产科学 2019年第6期26卷 1116-1125页

作者：姜晓东成永旭潘建林李晓东吴旭干上海海洋大学农业农村部淡水种质资源重点实验室上海海洋大学水产动物遗传育种上海市协同创新中心上海海洋大学水产科学国家级实验教学示范心江苏省淡水水产研究所盘锦光合蟹业有限公司

为鉴别不同地理种群野生中华绒螯蟹(Eriocheirsinensis),运用基于地标点法的几何形态测量学方法研究长江、黄河、辽河、瓯江、闽江及图们江中野生中华绒螯蟹头胸甲的形态特征。主要步骤为先通过地标点法提取中华绒螯蟹头胸甲上特征点的... 详细信息

为鉴别不同地理种群野生中华绒螯蟹(Eriocheirsinensis),运用基于地标点法的几何形态测量学方法研究长江、黄河、辽河、瓯江、闽江及图们江中野生中华绒螯蟹头胸甲的形态特征。主要步骤为先通过地标点法提取中华绒螯蟹头胸甲上特征点的坐标值,然后进行相对扭曲主成分分析和判别分析来区分6种群中华绒螯蟹头胸甲,最后利用薄板样条分析和网格变形将头胸甲形态变异矢量可视化。结果表明:(1)主成分散点图显示各群体之间虽有部分重叠,但大体可以形成较为集中的区域;(2)网格变形图显示各群体头胸甲的形态差异主要为额刺和侧刺长度;(3)逐步判别分析中各群体的判别准确率为80%～96%,存在一定的错判风险;(4)聚类分析将6群体中华绒螯蟹聚为两支,其中长江、黄河、瓯江和闽江个体被聚为一支,辽河和图们江个体被聚为另外一支。综上,以头胸甲为研究对象的地标点几何形态测量法是区分不同水系野生中华绒螯蟹的有效手段,但仍需要结合传统形态学测量方及遗传结构分析加以辅助证实。

关键词：中华绒螯蟹地理种群几何形态学地标点法群体识别