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Journal of Geoscience and Environment Protection 2018年第8期6卷 25-37页

作者： Dehe Liu jingfei you Qijie Xie Yuanyuan Huang Huajun Tong Yongchun County Meteorological Bureau of Fujian Province Yongchun China Quanzhou Meteorological Bureau of Fujian Province Quanzhou China Nan’an Meteorological Bureau of Fujian Province Nan’an China

To analyze the characteristics of drought and flood variations in Quanzhou during recent 55 years, the standardized precipitation index (SPI) and Empirical Orthogonal Function (EOF) and Rotated Empirical Orthogonal Function (REOF) were calculated by using the monthly precipitation data from 6 meteorological bureaus across Quanzhou for 1960-2014. Results showed that: 1) During 1960-2014, the drought and flood showed Periodic variation characteristics in Quanzhou, the specific period of frequent drought was 1963-1972, 1977-1986 and 2009-2011, and the specific period of frequent flood was 1961-1962, 1972-1975, 1990-1992 and 1997-2007;the drought and flood did not have significant tendency of variation in Spring and Summer, and the drought and flood showed a non-significant downward trend in Autumn and Winter. 2) The drought and flood variation had relatively consistent trend in Quanzhou, but there was a big difference on the northwest mountainous area, the middle semi-mountainous area and the southeast coast area in some periods. 3) The precipitation cell and distribution in every season were Nan’an and Anxi, but there was a big difference in rainfall less area: it was Yongchun and Dehua in Spring, Chongwu and Jinjiang in Summer, Chongwu in Autumn, Dehua and Chongwu in Winter.

关键词： Standardized Precipitation Index Drought and Flood Empirical Orthogonal Function (EOF) Rotated Empirical Orthogonal Function (REOF)

Cyber-physical Collaborative Restoration Strategy for Power Transmission System Considering Maintenance Scheduling

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1331-1341页

作者： Baozhong Ti Chuanyun Zhang jingfei Liu Zhaoyuan Wu Ziyang Huang North China Branch of State Grid Corporation of China Beijing 100053China State Grid Beijing Electric Power Company Beijing 100031China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of Electrical and Electronic EngineeringNorth China Electric Power UniversityBeijing 102206China IEEE CSEE

In order to improve the ability of power transmission system to cope with compound faults on the communication side and power side,a cyber-physical collaborative restoration strategy is ***,according to the information system’s role in fault diagnosis,remote control of equipment maintenance and automatic output adjustment of generator restoration,a cyber-physical coupling model is *** this basis,a collaborative restoration model of power transmission system is established by studying interactions among maintenance schedule paths,information system operation,and power system *** on power flow linearization and the large M-ε method,the above model is transformed into a mixed integer linear programming model,whose computational burden is reduced further by the clustering *** to the parameters of IEEE39 New England system,the geographic wiring diagram of the cyber-physical system is *** results show the proposed restoration strategy can consider the support function of the information system and space-time coordination of equipment maintenance at both sides comprehensively to speed up load recovery progress.

关键词： Clustering method collaborative restoration cyber-physical power system maintenance scheduling power transmission system restoration

Numerical and experimental research on axial injection end-burning hybrid rocket motors with polyethylene fuel

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Chinese Journal of Aeronautics 2024年第8期37卷 91-105页

作者： Xiangyu MENG Hui TIAN Lingfei HE jingfei GAO Xiaoting NIU Guobiao CAI School of Astronautics Beihang UniversityBeijing 100191China Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies Ministry of EducationBeijing 100816China

This study investigates the end-burning hybrid rocket motors with polyethylene fuel by the numerical simulation and *** on computational fluid dynamics,a numerical model is *** model is validated by two firing tests in this hybrid rocket motor,which uses oxygen and polyethylene as *** results show that the numerical and experimental data are in good agreement,and the error of the chamber pressure is less than 2.63%.Based on the simulation mode,the blowoff limit of the end-burning hybrid rocket motors is *** the nozzle throat diameter and the inner diameter of grain are large,it is more difficult for the hybrid rocket motor to achieve end-burning mode,i.e.,the flame spreading is prevented in the narrow *** main reason is that when the nozzle throat and the grain port are large,chamber pressure and oxidizer flow velocity are ***,the friction velocity considering the pressure and flow velocity is *** critical friction velocity is about 4.054–4.890 m/s in the hybrid rocket *** the friction velocity exceeds the critical friction velocity,the combustion mode in hybrid rocket motors changes from the flame spreading mode to the end-burning ***,the regression rate formula is obtained by fitting,which shows that the regression rate has a good correlation with combustion chamber *** critical friction velocity and regression rate formula can provide an important reference for end-burning hybrid rocket motors.

关键词： Hybrid rocket motor End burning Blowoff limit Flame propagation Regression rate

Sono-assembly of folate-decorated curcumins/alginate core-shell microcomplex and its targeted delivery and pH/reduction dual-triggered release

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Particuology 2024年第1期84卷 168-177页

作者： Qingye Meng Shuangling Zhong jingfei Wang Zhenqian Zhang Yan Gao Xuejun Cui College of Chemistry Jilin University Changchun130012China College of Resources and Environment Jilin Agricultural University Changchun130118China State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun130012China Weihai Institute for Bionics-Jlin University Weihai264400China

In this study,sodium alginate(SA),a non-toxic natural polysaccharide with good biocompatibility and biodegradability,was developed for targeted delivery of curcumin(CUR)in tumor *** strategy is to sulfhydrylate the folic acid(FA)modified SA,and the CUR dissolved in ethyl acetate(EAC)phase is coated in microcapsules by a quick,efficient and environment-friendly sonochemical *** EAC in the microcapsule core is volatile,which can be recycled and reused to reduce *** prepared mi-crocapsules(FA-RSMCs@CUR)exhibited similar toxicity to free curcumin in anti-tumour evaluation in ***-RSMCs@CUR also exhibited effective antibacterial properties in the antibacterial evaluation in *** is expected to become a low-cost tumor targeting vector in the future,and has the potential to be promoted in clinical application.

关键词： Reductive-responsive Sodium alginate Microcapsule Targeted delivery Sonochemical

Competitive interactions between invasive fall armyworm and Asian corn borer at intraspecific and interspecific level on the same feeding guild

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Insect Science 2024年第4期31卷 1313-1325页

作者： jingfei Guo Jianqin Shi Hailiang Han Ivan Rwomushana Abid Ali Yeeyee Myint Zhenying Wang State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina Zhejiang Dongyang Maize Research Institute DongyangZhejiangChina CAB International(CABI) NairobiKenya Department of Entomology University of AgricultureFaisalabadPunjabPakistan Plant Protection Division Department of AgricultureMinistry of AgricultureLivestock and IrrigationYangonMyanmar

Interspecific competition is an important factor in the population dynamics and geographical distribution of insect *** armyworm(FAW),Spodoptera frugiperda,an invasive species,and the Asian corn borer(ACB),Ostrinia furnacalis,a native pest species are major pests on maize in China,posing a threat to maize yield and grain quality.A series of laboratory,greenhouse,and field experiments were conducted to elucidate the competitive interactions between FAW and *** the laboratory experiments,FAW exhibited aggressive behaviors more frequently when compared with ACB,while the latter species exhibited defense behaviors more *** intraspecific competition was recorded in the FAW conspecific rather than in ACB,particularly in the 6th larval *** had a higher interspecific competitive advantage through intraguild predation over ACB,resulting in partial or complete displacement ACB when initially the ratio of the 2 species was 1:*** interspecific competition also had significantly influenced on the population parameters,defensive enzymes,and nutrient of these 2 *** interaction proved that the response of superoxide,catalase,and soluble protein in FAW were significantly increased,whereas the total sugar content in both species was substantially *** rate,and the plant damage that co-infested by both species varied significantly among the sequential combinations under greenhouse and field *** consistently exhibited stronger intraspecific aggression than ACB under laboratory and field conditions when co-existing on the same feeding *** findings contribute to efforts toward the improvement of integrated pest management programs for FAW,in decision making for invasive and native pests’management strategies to reduce the high risks of FAW and ACB outbreaks.

关键词： Asian corn borer defensive enzyme fall armyworm interspecific competition intraspecific competition survival rate

Control of temperature dependent viscosity for manufacturing of Bi-doped active fiber

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International Journal of Extreme Manufacturing 2024年第3期6卷 522-530页

作者： Rui Duan jingfei Chen Hao Ke Tianxia Wei Ke Zhang Xueliang Li Xu Feng Qiuju Zheng Zhixue He Jianrong Qiu Shifeng Zhou State Key Laboratory of Luminescent Materials and Devices School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510640People’s Republic of China Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques Guangdong Engineering Technology Research and Development Center of Special Optical Fiber Materials and DevicesGuangzhou 510640People’s Republic of China School of Materials Science and Engineering Qilu University of TechnologyJinanPeople’s Republic of China Peng Cheng Laboratory Shenzhen 518000People’s Republic of China College of Optical Science and Engineering State Key Laboratory of Modern Optical InstrumentationZhejiang UniversityHangzhou 310027People’s Republic of China

Bi-activated photonic materials are promising for various applications in high-capacity telecommunication,tunable laser,and advanced bioimaging and *** various Bi-doped material candidates have been explored,manufacturing of Bi heavily doped fiber with excellent optical activity remains a long-standing ***,a novel viscosity evolutional behavior mediated strategy for manufacturing of Bi-doped active fiber with high dopant solubility is *** intrinsic relation among the evolution of Bi,reaction temperature and viscosity of the glass system is ***,the effective avenue to prevent the undesired deactivation of Bi during fiber drawing by tuning the temperature dependent viscosity evolution is *** applying the strategy,for the first time we demonstrate the success in fabrication of heavily doped Bi active ***,the principal fiber amplifier device is constructed and broadband optical signal amplification is *** findings indicate the effectiveness of the proposed temperature dependent viscosity mediated strategy for developing novel photonic active fiber,and they also demonstrate the great potential for application in the next-generation high-capacity telecommunication system.

关键词： infrared luminescence active fiber optical amplification

场景经济驱动新质生产力生成:理论逻辑、现实挑战与实践进路

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青海社会科学 2024年第3期 81-89页

作者：冉净斐郑州轻工业大学经济与管理学院

场景经济是促进新质生产力发展的重要路径。场景经济之所以能够促进新质生产力生成,主要是由于场景经济能够有效地实现市场需求和企业技术对接;可以促进要素集聚发挥规模经济优势;能够有效促进新产业和新的商业模式形成;可以通过组建紧... 详细信息

场景经济是促进新质生产力发展的重要路径。场景经济之所以能够促进新质生产力生成,主要是由于场景经济能够有效地实现市场需求和企业技术对接;可以促进要素集聚发挥规模经济优势;能够有效促进新产业和新的商业模式形成;可以通过组建紧密型创新联合体来促进技术创新。但是,场景经济在促进新质生产力生成中也面临着挑战:社会对场景经济驱动新质生产力的重要性认识不足;企业对场景模式下消费者需求的把握不准;企业运用场景驱动科技创新的动力不足;组织发展场景经济的联合共同体协同性不够。应对挑战需要从战略上高度重视场景经济的发展,促使企业正确把握场景的消费者需求,增强企业运用场景的动力机制,加强紧密型联合创新共同体的协作,制定促进场景经济发展的法律规则。

关键词：场景经济新质生产力场景驱动科技创新

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北魏“阴山却霜”习俗新解

中国历史地理论丛 2024年第1期39卷 138-144页

作者：牛敬飞陕西师范大学历史文化学院陕西西安710119

从西晋末年到北魏开国,拓跋鲜卑在其境内大力发展农耕,农业已成为北魏新的经济支柱。北魏恰逢气候史上的寒冷期,《魏书·灵征志》有大量关于霜灾的记录。阴山、平城一带频发的霜灾制约了当地农业之发展,故拓跋氏才形成了“阴山却霜”习... 详细信息

从西晋末年到北魏开国,拓跋鲜卑在其境内大力发展农耕,农业已成为北魏新的经济支柱。北魏恰逢气候史上的寒冷期,《魏书·灵征志》有大量关于霜灾的记录。阴山、平城一带频发的霜灾制约了当地农业之发展,故拓跋氏才形成了“阴山却霜”习俗“。阴山却霜”与鲜卑游牧旧俗关系不大,它是北魏中前期转向以农立国的见证。

关键词：北魏阴山却霜平城农业

Nursing Experience of Early Application of Nasoenteric Tube for Enteral Nutrition in Critically Ill ICU Patients

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Journal of Clinical and Nursing Research 2024年第8期8卷 276-282页

作者： Jingjing Xin jingfei Song Jing Wang Qingdao Chest Hospital Qingdao 266100Shandong ProvinceChina

Objective:To investigate the effective nursing measures of early application of nasoenteric tube for enteral nutrition in critically ill patients in ICU,and to summarize the nursing ***:The study was carried out in June 2023–November 2023.62 samples of ICU critically ill patients were selected,all of whom used enteral nutrition by mesenteric tube and were grouped into an observation group(n=31)and a control group(n=31)by using the numerical table randomization *** patients in the control group were basic nursing interventions,and the patients in the observation group were comprehensive quality care,comparing the nutritional indexes,complication rates,and nursing satisfaction between the two ***:All nutritional indicators of the observation group were higher than those of the control group after nursing intervention(P<0.05);the complication rate of the observation group was lower than that of the control group(P<0.05);the nursing satisfaction of the observation group was higher than that of the control group(P<0.05).Conclusion:Comprehensive quality nursing care during the early application of a gastroenteric tube for enteral nutrition in critically ill patients in the ICU can improve nutritional indexes,reduce the incidence of complications and improve nursing satisfaction.

关键词： ICU critically ill patients Nasoenteric tube Enteral nutrition Nursing care

泉州市国家级地面气象观测站探测环境现状评估分析

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中国资源综合利用 2018年第8期36卷 179-181页

作者：杨苏勤尤竞飞福建省南安市气象局福建南安362300 福建省泉州市气象局福建泉州362000

2013年,泉州市分别测量了市局所属的地面气象观测站的气象探测环境。本文以此为例,综合评估了影响泉州市地面气象观测站探测环境的主要因子,分析了气象观测站的探测环境现状。结果表明,泉州市地面气象观测站探测环境遭受城市建筑的破坏... 详细信息

2013年,泉州市分别测量了市局所属的地面气象观测站的气象探测环境。本文以此为例,综合评估了影响泉州市地面气象观测站探测环境的主要因子,分析了气象观测站的探测环境现状。结果表明,泉州市地面气象观测站探测环境遭受城市建筑的破坏程度最为严重,海岛无人自动气象站的探测环境受自然环境(如植被的生长等)的破坏影响较大,泉州市地面气象观测站面临依法保护性台站迁移的窘境,探测环境的保护还有待进一步加强。

关键词：泉州市地面气象观测站可视障碍物仰角图与全景照评估分析探测环境