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分布式光纤传感在PCCP断丝监测中的应用研究

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水利建设与管理 2025年第1期45卷 27-31页

作者：段维维赵士海王文凯辽宁智水数字科技有限责任公司辽宁沈阳110000 北京国电瑞源科技发展有限公司北京100141

断丝是影响管道结构健康运行的主要因素之一。为保障PCCP管线正常安全工作,本文提出了一种基于分布式光纤传感的PCCP断丝监测系统。通过敷设在管道内壁的一根传感光缆,系统能够对服役管线中破坏其性能的断丝事件进行全方位、无死角的快... 详细信息

断丝是影响管道结构健康运行的主要因素之一。为保障PCCP管线正常安全工作,本文提出了一种基于分布式光纤传感的PCCP断丝监测系统。通过敷设在管道内壁的一根传感光缆,系统能够对服役管线中破坏其性能的断丝事件进行全方位、无死角的快速检测。试验模拟进行了管道断丝破坏,结果表明,空管时断丝信号频率主要集中在300~1000Hz,高频部分整体能量相比断丝前有所增加;管道带水时,1000Hz附近的能量占比下降,部分能量向高频部分转移,主要集中在3000Hz、4300Hz以及4700Hz频带附近。以上发现可为后续深度学习断丝信号特征、提高断丝识别准确率提供样本支撑。

关键词：分布式光纤管道安全断丝监测信号频率时域波形

Novel metabolic and physiological functions of branched chain amino acids: a review

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Journal of Animal Science and Biotechnology 2017年第3期8卷 501-512页

作者： shihai Zhang Xiangfang Zeng Man Ren Xiangbing Mao Shiyan Qiao State Key Laboratory of Animal Nutrition College of Animal Science and Technology China Agricultural University College of Animal Science South China Agricultural University College of Animal Science Anhui Science & Technology University Animal Nutrition Institute Key Laboratory of Animal Disease-Resistance NutritionMinistry of Education Sichuan Agricultural University

It is widely known that branched chain amino acids（BCAA） are not only elementary components for building muscle tissue but also participate in increasing protein synthesis in animals and humans. BCAA（isoleucine, leucine and valine） regulate many key signaling pathways, the most classic of which is the activation of the m TOR signaling pathway. This signaling pathway connects many diverse physiological and metabolic roles. Recent years have witnessed many striking developments in determining the novel functions of BCAA including：（1） Insufficient or excessive levels of BCAA in the diet enhances lipolysis.（2） BCAA, especially isoleucine, play a major role in enhancing glucose consumption and utilization by up-regulating intestinal and muscular glucose transporters.（3）Supplementation of leucine in the diet enhances meat quality in finishing pigs.（4） BCAA are beneficial for mammary health, milk quality and embryo growth.（5） BCAA enhance intestinal development, intestinal amino acid transportation and mucin production.（6） BCAA participate in up-regulating innate and adaptive immune *** addition, abnormally elevated BCAA levels in the blood（decreased BCAA catabolism） are a good biomarker for the early detection of obesity, diabetes and other metabolic diseases. This review will provide some insights into these novel metabolic and physiological functions of BCAA.

关键词： Amino acid transporters Glucose transporters Gut health Immunity Lipolysis Mammary health Meat quality Milk production

Effects of substituting Ni with M (M=Cu, Al and Mn) on microstructures and electrochemical characteristics of La-Mg-Ni system (PuNi_3-type) electrode alloys

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Rare Metals 2006年第z1期25卷 25-32页

作者： ZHANG Yanghuan ZHAO Dongliang DONG Xiaoping REN Huiping GUO shihai WANG Xinlin Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China School of Material Inner Mongolia University of Science and Technology Baotou 014010 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China School of Material University of Science and Technology Beijing Beijing 100083 China School of Material Inner Mongolia University of Science and Technology Baotou 014010 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China

In order to improve the electrochemical cycle stability of La-Mg-Ni system (PuNi3-type) hydrogen storage alloy, Ni in the alloys was partially substituted by M (M=Cu, Al, Mn). A new La-Mg-Ni system electrode alloys La0.7Mg0.3Ni2.55-xCo0.45Mx (M=Cu, Al, Mn; x=0, 0.1) were prepared by casting and rapid quenching. The effects of element substitution and rapid quenching on the microstructures and electrochemical performances of the alloys were investigated. The results by XRD, SEM and TEM show that the alloys have a multiphase structure, including the (La, Mg)Ni3 phase, the LaNi5 phase and the LaNi2 phase. The rapid quenching and element substitution have an imperceptible influence on the phase compositions of the alloys, but both change the phase abundance of the alloys. The rapid quenching significantly improves the composition homogeneity of the alloys and markedly decreases the grain size of the alloys. The Cu substitution promotes the formation of an amorphous phase in the as-quenched alloy, and a reversal result by the Al substitution. The electrochemical measurement indicates that the element substitution decreases the discharge capacity of the alloys, whereas it obviously improves the cycle stability of the alloys. The positive influence of element substitution on the cycle life of the alloys is in sequence Al>Cu>Mn, and negative influence on the discharge capacity is in sequence Al>Mn>Cu. The rapid quenching significantly enhances the cycle stability of the alloys, but it leads to a different extent decrease of the discharge capacity of the alloys.

关键词： element substitution rapid quenching La-Mg-Ni system electrode alloy microstructures electrochemical performances

Structure and Corrosion Resistance of Microarc Oxidation Coatings on AZ91D Magnesium Alloy

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Journal of Rare Earths 2004年第z2期22卷 38-41页

作者： Cui shihai Han Jianmin Li Weijing Li Ronghua Zhu Xiaowen Wang Jinhua School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

Magnesium alloys are widely used as shells of 3C (computer, mobile phone and consumer electronics) equipments for its impressive mechanical and physical properties, such as low density, good resistance to electromagnetic radiation, suitable for high pressure diecasting and easily recycling, etc. But poor corrosion resistance confines its extensively application. In this paper, protective coatings was successfully prepared on AZ91D magnesium alloys by micro-arc oxidation (MAO) and painting process. Microstructures and phases of MAO coatings were invesgated with scanning electron microscope (SEM) and X-Ray diffractometer. Mechanical properties of MAO coating, such as adhesive force and corrosion resistance, were also tested. Results showed that MAO coatings were a good base for painting process. MAO coatings with paint have good adhesive properties to base metal and excellent corrosion resistance. Micro-arc oxidation with painting process is a good kind of surface treatment to improve the corrosion resistance of mobile phone shell made of AZ91D magnesium alloys.

关键词： magnesium alloy micro-arc oxidation microstructure corrosion resistance adhesive

Kalman-Filtering-Based Frequency Control Strategy Considering Electrolytic Aluminum Load

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Energy Engineering 2022年第4期119卷 1517-1529页

作者： Yuqin Chen shihai Yang Yueping Kong Mingming Chen Marketing Service Center State Grid Jiangsu Electric Power Co.Ltd.Nanjing210004China

Traditional thermal power units are continuously replaced by renewable energies,of which fluctuations and intermittence impose pressure on the frequency stability of the power *** aluminum load(EAL)accounts for large amount of the local electric loads in some *** participation of EAL in local frequency control has huge application ***,the controller design of EAL is difficult due to the measurement noise of the system frequency and the nonlinear dynamics of the EAL’s electric power *** on this problem,this paper proposes a control strategy for EAL to participate in the frequency *** the controller design of the EAL system,the system frequency response model is established and the EAL transfer function model is developed based on the equivalent circuit of *** the problem of load-side frequency measurement error,the frequency estimation method based on Kalman-filtering is *** improve the performance of EAL in the frequency control,a fuzzy EAL controller is *** testing examples show that the designed Kalman-filter has good performance in de-noising the measured frequency,and the designed fuzzy controller has better performance in stabilizing system frequency than traditional methods.

关键词： Electrolytic aluminum load kalman-filtering frequency control

Energy-and spectral-efficiency of zero-forcing beamforming in massive MIMO systems with imperfect reciprocity calibration: bound and optimization

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Science China(Information Sciences) 2018年第12期61卷 163-177页

作者： Donglin LIU Fei WU Xin QUAN Wanzhi MA Ying LIU shihai SHAO National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China

In a time-division duplex(TDD) system with massive multiple input multiple output(MIMO),channel reciprocity calibration(RC) is generally required in order to cope with the reciprocity mismatch between the uplink and downlink channel state information. Currently, evaluating the achievable spectral efficiency(SE) and energy efficiency(EE) of TDD massive MIMO systems with imperfect RC(IRC) mainly relies on exhausting Monte Carlo simulations and it is infeasible to precisely and concisely quantify the achievable SE and EE with IRC. In this study, a novel method is presented for tightly bounding the achievable SE of massive MIMO systems with zero-forcing beamforming under IRC. On the basis of the analytical results, we demonstrate key insights for practical system design with IRC in three aspects: the scaling rule for interference power, saturation region of the SE, and the bound on the SE loss. Finally, the trade-off between spectral and energy efficiencies in the presence of IRC is determined with algorithms developed to optimize SE(EE) under a constrained EE(SE) value. The loss of optimal total SE and EE due to IRC is also quantified, which shows that the loss of optimal EE is more sensitive to IRC in a typical range of transmit power values.

关键词： massive MIMO ZF beamforming TDD reciprocity calibration spectral and energy efficiencies

Highly Improved Electrochemical Performances of the Nanocrystalline and Amorphous Mg_2Ni-type Alloys by Substituting Ni with M (M=Cu,Co,Mn)

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Journal of Wuhan University of Technology(Materials Science) 2017年第3期32卷 685-694页

作者：张羊换 YUAN Zeming YANG Tai ZHAI Tinging LIU Zhuocheng GUO shihai Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources Inner Mongolia University of Science and Technology Department of Functional Material Research Central Iron and Steel Research Institute

The element Ni in the Mg2Ni alloy is partially substituted by M（M = Cu, Co, Mn） in order to ameliorate the electrochemical hydrogen storage performances of Mg2Ni-type electrode alloys. The nanocrystalline and amorphous Mg20Ni10-xMx（M = None, Cu, Co, Mn; x = 0-4） alloys were prepared by melt spinning. The effects of the M（M = Cu, Co, Mn） content on the structures and electrochemical hydrogen storage characteristics of the as-cast and spun alloys were comparatively studied. The analyses by XRD, SEM and HRTEM reveal that all the as-cast alloys have a major phase of Mg2Ni but the M（M = Co, Mn） substitution brings on the formation of some secondary phases, MgCo2 and Mg for the（M = Co） alloy, and Mn Ni and Mg for the（M = Mn） alloy. Besides, the as-spun（M = None, Cu） alloys display an entirely nanocrystalline structure, whereas the as-spun（M = Co, Mn） alloys hold a nanocrystalline/amorphous structure, suggesting that the substitution of M（M = Co, Mn） for Ni facilitates the glass formation in the Mg2Ni-type alloys. The electrochemical measurements indicate that the variation of M（M = Cu, Co, Mn） content engenders an obvious effect on the electrochemical performances of the as-cast and spun alloys. To be specific, the cyclic stabilities of the alloys augment monotonously with increasing M（M = Cu, Co, Mn） content, and the capacity retaining rate（S20） is in an order of（M = Cu）〉（M = Co）〉（M = Mn）〉（M = None） for x≤1 but changes to（M = Co）〉（M = Mn）〉（M = Cu）〉（M = None） for x≥2. The discharge capacities of the as-cast and spun alloys always grow with the rising of M（M = Co, Mn） content but first mount up and then go down with increasing M（M = Cu） content. Whatever the M content is, the discharge capacities are in sequence：（M = Co）〉（M = Mn）〉（M = Cu）〉（M = None）. The high rate discharge abilities（HRDs） of all the alloys grow clearly with rising M（M = Cu, Co） content except for（M = Mn） alloy, whose HRD has a maximum value with varying M（M = Mn） content. Furthermore, for the as-

关键词： Mg2Ni-type alloy element substitution melt spinning nanocrystalline and amorphous electrochemical performances

Lewis base catalyzed ring-expansion of isatin with 2,2,2-trifluorodiazoethane(CF3CHN2):An efficient route to3-hydroxy-4-(trifluoromethyl)quinolinones

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Chinese Chemical Letters 2020年第6期31卷 1568-1571页

作者： Shuaipeng Lv Yunfang Sun Yue Xu shihai Yang Lei Wang Department of Traditional Chinese Medicine Jilin Agricultural UniversityChangchun 130118China Institute of Medicinal Plant Development Chinese Academy of Medical Science&Peking Union Medical CollegeBeijing 100193China

A Lewis base catalyzed ring expansion of isatin with 2,2,2-trifluorodiazoethane(CF3 CHN2)is *** is characterized that the merge of tetramethylethylenediamine and CF3 CHN2 generates reactive triazene intermediates,which construct substituted 3-hydroxy-4-(trifluoromethyl)quinolinones with high *** application of the procedure is broadened by 3-trifluormethylpyrazole fused3-hydroxy-4-(trifluoromethyl)quinolinone synthesis.

关键词： Ring-expansion Lewis base Heterocycle Quinolinones Triazene

新时代党的创新理论传播的系统矩阵——以传播学五大范畴为视点

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河北大学学报（哲学社会科学版） 2025年第1期50卷 99-109页

作者：尤文梦山东大学马克思主义学院山东济南250100

习近平新时代中国特色社会主义思想内涵丰富、思想宏阔、逻辑严密,对丰富发展马克思主义作出了一系列原创性贡献,想要转化为推动中国式现代化的磅礴力量,传播最为关键。从社会传播范畴出发,推动新时代党的创新理论传播要着力架构涵盖人... 详细信息

习近平新时代中国特色社会主义思想内涵丰富、思想宏阔、逻辑严密,对丰富发展马克思主义作出了一系列原创性贡献,想要转化为推动中国式现代化的磅礴力量,传播最为关键。从社会传播范畴出发,推动新时代党的创新理论传播要着力架构涵盖人内传播、人际传播、群体传播、组织传播和大众传播在内的“五位一体”的多层次、立体化传播矩阵,积极寻求新时代党的创新理论与大众思想文化的共通意义空间,使理论传播体现时代性、把握规律性、富于创造性,才能以理论的深度、视野的宽度、语言的温度及传播的力度巩固壮大主流思想舆论,让新时代党的创新理论成为时代最强音,用“中国理论”凝聚“中国力量”。

关键词：党的创新理论传播习近平新时代中国特色社会主义思想