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1,4-双氯甲基-2-甲氧基-5-烷氧基苯的合成

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山东师范大学学报（自然科学版） 1999年第2期14卷 154-157页

作者：王建营李银奎龙永福国防科工委军事医学研究所国防科技大学材料工程与应用化学系沂水县第二中学

以对甲氧基苯酚为起始原料，以甲醛、多聚甲醛和浓盐酸为双氯甲基化试剂，合成了一系列的１，４－双氯甲基－２－甲氧基－５－烷氧基苯．产率较高。

关键词：甲氧基烷氧基苯合成双氯甲基化双氯甲基苯

Condition monitoring and diagnosis of power equipment:review and prospective

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High Voltage 2017年第2期2卷 82-91页

作者： Shengtao li jianying li State Key Laboratory of Electrical Insulation and Power equipment Xi'an Jiaotong UniversityXi'an710049People's Republic of China

To ensure the power system operates safely and reliably,it is essential to monitor and evaluate the health condition of power equipment on-line or *** study reviews the research status in condition monitoring and diagnosis of power equipment,including transformer,gas insulated switchgear,cable,external insulation,generator,and power capacitor in recent *** much progress has been made in technologies of condition monitoring and fault diagnosis such as test accuracy,fast and accurate fault localisation and recognition of fault types,there are still many deficiencies which needs further research work,including the reliability of signal collection from sensors,the accuracy of data treatment and analysis,anti-interference performance of test equipment,appropriate models used for condition *** prospective of condition monitoring and diagnosis technologies of power equipment are also presented in this *** is proposed that the application of big data,internet of things and cloud computing should be expected and given special attention in the near future.

关键词： diagnosis power fault

Simultaneous attack of a stationary target using multiple missiles: a consensus-based approach

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Science China(Information Sciences) 2017年第7期60卷 67-80页

作者： Jialing ZHOU jianying YANG Zhongkui li State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering ScienceCollege of Engineering Peking University

This paper considers the simultaneous attack problem of multiple missiles against a stationary target. Built upon the classic proportional navigation structure, we propose a consensus-based approach to design the cooperative guidance law. Specifically, we present time-varying navigation ratios for the missiles,which exchange the time-to-go estimates between neighboring missiles via a communication network. For the cases where the communication topology is undirected or in the leader–follower structure with a missile acting as the leader whose navigation ratio cannot be tuned, we show that the proposed cooperative guidance law can solve the simultaneous attack problem. The effectiveness of the theoretical results is finally illustrated by numerical simulations.

关键词： simultaneous attack consensus problem cooperative control distributed control guidance law design

Numerical investigation of a novel pattern for reducing residual stress in metal additive manufacturing

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Journal of Materials Science & Technology 2021年第8期67卷 11-22页

作者： li Sun Xiaobo Ren jianying He Zhiliang Zhang Department of Structural Engineering Norwegian University of Science and Technology(NTNU)Trondheim 7491Norway SINTEF Industry Trondheim 7456Norway

Deposition patterns can significantly affect residual stress distribution in additive manufacturing *** this paper,a novel pattern,the S-pattern,is proposed for the metal additive manufacturing *** finite element method is used to study the temperature field and the stress field of a cuboid structure under the S-pattern and five other representative patterns:zig-zag,raster,alternate-line,in-out spiral,and out-in *** results show that the S-pattern achieves the lowest values of both equivalent residual stress and maximum principal residual stress,and the warpage of the S-pattern is close to that of *** analyzing the temperature and stress fields under all patterns,it is found that the residual stress distribution is determined by the uniformity of temperature distribution which is correlated with the peak temperatures of *** equivalent residual stress and the maximum principal residual stress are inversely correlated with the average peak temperature and the minimum peak temperature of corners,*** correlations between temperature and residual stress provide an effective approach to evaluate the residual stress of different patterns and guide the deposition process in practice.

关键词： Additive manufacturing(AM) Deposition pattern Temperature distribution Residual stress Warpage

The Combined Effects of the Tropical and Extratropical Quasi-biweekly Oscillations on the Record-setting Mei-yu Rainfall in the Summer of 2020

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Advances in Atmospheric Sciences 2023年第4期40卷 663-681,I0002-I0014页

作者： Zhen HUANG Shuanglin li jianying li Chao ZHANG Department of Atmospheric Science/Centre for Severe Weather and Climate and Hydro-geological Hazards China University of GeosciencesWuhan 430074China China Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological SciencesBeijing 100081China

During June-July 2020,the strongest recorded mei-yu rainfall occurred in the middle and lower reaches of the Yangtze *** rainfall processes exhibited an obvious quasi-biweekly(biweekly in brief)variability,and there are altogether five *** is found that the biweekly rainfall cycle mainly arises from the collaborative effects of biweekly variabilities from both the tropics and *** for the tropics,the biweekly meridional march and retreat of the western Pacific subtropical high(WPSH)is particularly *** for the extratropics,geopotential height anomalies near Lake Baikal are *** former is attributed to the intensified biweekly activity of the southwest-northeast oriented EastAsian Pacific wave train(EAP)originating from the tropical western Pacific,while the latter is associated with the biweekly activities of the eastward propagating Eurasia mid-high latitudinal wave train and the westward propagating North Pacific wave *** the biweekly activities of these wave trains intensified is further diagnosed from the perspective of thermodynamical forcing and also from the modulation of interannual background on intraseasonal *** is found that the strongest recorded convection anchoring over the tropical western Indian Ocean(IO)triggers anomalous descent over the tropical western Pacific,which modulates the biweekly activity of the ***,the anomalous diabatic heating over the IO causes changes of the meridional thermodynamic contrast across the IO to the high latitudes,which modulates the extratropical wave trains.A further diagnosis of barotropic kinetic energy conversion suggests that the active occurrence of two extratropical biweekly wave trains is attributed to the increased efficiency of energy conversion from basic *** westward propagation of the extratropical North Pacific wave train is attributed to the weakened and northshifted upper-level westerly,which is caused by the SST warmth near the Kuroshio

关键词： strongest recorded mei-yu rainfall in summer 2020 quasi-biweekly variability tropical convection westward propagation of the extratropical North Pacific wave train SSTA in the North Pacific

Heavy collecting induces smaller and deeper Fritillariae Cirrhosae Bulbus in the wild

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Plant Diversity 2017年第4期39卷 208-213页

作者： Xinhui li lin liu Xu Gu jianying Xiang College of Environmental Science and Engineering Southwest Forestry University Kunming 650224 China Shangri-La Alpine Botanical Garden Shangri-la 674400 China Yunnan Academy of Biodiversity Southwest Forestry University Kunming 650224 China

Fritillariae Cirrhosae Bulbus is a well-known traditional Chine medicinal herb. However, the demand for this herb is leading to over-collection and its decline in the wild. This study aims to investigate the ecological conditions of Fritillaria cirrhosa under the influence of human disturbance, biotic species interactions and climatic conditions. We established a total of 78 plots at 14 sites of F. cirrhosa in its distribution center, the Hengduan Mountains area. At each site, we estimated the abundance of F. cirrhosa at different distances from roads. The diameter and height of F. cirrhosa fruit and bulbs were measured and compared to underground bulb depth. We then analyzed the effects of environmental conditions and human disturbance on the abundance of F. cirrhosa using variance partitioning. We found that(1)abundance of F. cirrhosa and their underground bulb depth showed a significant linear increase with the distance from the main road;(2) the diameter/height of fruits and the diameter/height of fruits/bulbs showed significantly different responses to the human disturbance;(3) the community associates,climate and spatial conditions can explain 58%, 22% and 27%, respectively, of the variance in the F. cirrhosa abundance. These results highlight the fact that human disturbance and biotic factors have a great influence on the survival of F. cirrhosa, even more than climate conditions.

关键词： Fritillaria cirrhosa Human disturbance Plant abundance Biotic interactions

A Comparative Study on the Dominant Factors Responsible for the Weaker-than-expected El Ni?o Event in 2014

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Advances in Atmospheric Sciences 2015年第10期32卷 1381-1390页

作者： li jianying liU Boqi li Jiandong MAO Jiangyu State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences Chinese Academy of Meteorological Sciences Joint Center for Global Change Studies

Anomalous warming occurred in the equatorial central-eastern Pacific in early May 2014, attracting much attention to the possible occurrence of an extreme E1 Nifio event that year because of its similarity to the situation in early 1997. However, the subsequent variation in sea surface temperature anomalies （SSTAs） during summer 2014 in the tropical Pacific was evidently different to that in 1997, but somewhat similar to the situation of the 1990 aborted E1 Nifio event. Based on NCEP （National Centers for Environmental Prediction） oceanic and atmospheric reanalysis data, the physical processes responsible for the strength of E1 Nifio events are examined by comparing the dominant factors in 2014 in terms of the preceding instability of the coupled ocean-atmosphere system and westerly wind bursts （WWBs） with those in 1997 and 1990, separately. Although the unstable ocean-atmosphere system formed over the tropical Pacific in the preceding winter of 2014, the strength of the preceding instability was relatively weak. Weak oceanic eastward-propagating downwelling Kelvin waves were forced by the weak WWBs over the equatorial western Pacific in March 2014, as in February 1990. The consequent positive upper-oceanic heat content anomalies in the spring of 2014 induced only weak positive SSTAs in the central-eastern Pacific-unfavorable for the subsequent generation of summertime WWB sequences. Moreover, the equatorial western Pacific was not cooled, indicating the absence of positive Bjerknes feedback in early summer 2014. Therefore, the development of E1 Nifio was suspended in summer 2014.

关键词： El Nino event westerly wind burst instability of coupled ocean-atmosphere system positive Bjerknes feedback

Cooperative Guidance Law Design for Simultaneous Attack with Multiple Missiles Against a Maneuvering Target

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Journal of Systems Science & Complexity 2018年第1期31卷 287-301页

作者： ZHOU Jialing Lü Yuezu li Zhongkui YANG jianying Ministerial Key Laboratory of ZNDY School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China National Defense Key Laboratory of Science and Technology on Electromagnetic Scattering the 802 Institute of Shanghai Academy of Space Flight Technology the Eighth Academy of China Aerospace Science and Technology Corporation Shanghai 200090 China State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering Science College of Engineering Peking University Beijing 100871 China

This paper considers the simultaneous attack problem of multiple missiles against a maneuvering target. Different from most of the existing literature in which the simultaneous attack problem is formulated as a consensus problem of missiles＇ time-to-go estimates, this paper formulates it as the consensus problem of missiles＇ ranges-to-go. Based on this strategy, novel distributed guidance laws are proposed to solve the simultaneous attack problem with the target of unknown *** control method is introduced to estimate the upper bound of the target＇s acceleration. The effectiveness of the proposed guidance laws is verified both theoretically and numerically.

关键词： consensus problem distributed control guidance law design simultaneous attack

Power loss transition of stable ZnO varistor ceramics: Role of oxygen adsorption on the stability of interface states at the grain boundary

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Journal of Advanced Ceramics 2023年第5期12卷 972-983页

作者： Zhuolin Cheng Rou li Yiwei Long jianying li Shengtao li Kangning Wu State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an 710049China Department of Thermal and Fluid Engineering University of TwenteEnschede 7500AEthe Netherlands

Highly stable ZnO varistor ceramics with steadily decreasing power loss have been put into applications in electrical and electronic systems for overvoltage protections, even with the absence of general understandings on their aging behaviors. In this paper, we investigated their aging nature via conducting comparative direct current (DC) aging experiments both in air and in nitrogen, during which variations of electrical properties and interface properties were measured and analyzed. Notably, continuously increasing power loss with severe electrical degradation was observed for the sample aged in nitrogen. The power loss transition was discovered to be closely related to the consumption of oxygen adsorption at the grain boundary (GB), which could, however, remain constant for the sample aged in air. The interface density of states (DOS) Ni, which is crucial for pinning the potential barrier, was proved to decrease in nitrogen, but keep stable in air. Therefore, it is concluded that the oxygen adsorption at the GB is significant for the stability of interface states, which further correlates to the long-term stability of modern stable ZnO varistor ceramics.

关键词： ZnO varistor ceramics aging power loss oxygen adsorption interface states