Preliminary analysis for the roles of crustal low-velocity and high-conductivity body in process of strong earthquake preparation

In this paper, the roles of low velocity and high conductivity body inside the crust in the process of strong earth quake preparation are approached by using theoretical analysis method based on the comprehensive researches on the fine structure of strong seismic source in the North China. The following results are obtained. The low-velocity and high-conductivity body plays the promoting role for the action of deep-seated structure in the medium stage of earthquake preparation, except that its existence is advantageous to the stress concentrating in the overlying brittle layer during the process of earthquake preparation. And it plays the triggering role for the occurrence of strong earthquake in the later stage of earthquake preparation.

A Solvent-Free Covalent Organic Framework Single-Ion Conductor Based on Ion-Dipole Interaction for All-Solid-State Lithium Organic Batteries

Single-ion conductors based on covalent organic frameworks(COFs)have garnered attention as a potential alternative to currently prevalent inorganic ion conductors owing to their structural uniqueness and chemical versatility.However,the sluggish Li+conduction has hindered their practical applications.Here,we present a class of solvent-free COF single-ion conductors(Li-COF@P)based on weak ion-dipole interaction as opposed to traditional strong ion-ion interaction.The ion(Li+from the COF)-dipole(oxygen from poly(ethylene glycol)diacrylate embedded in the COF pores)interaction in the Li-COF@P promotes ion dissociation and Li+migration via directional ionic channels.Driven by this single-ion transport behavior,the Li-COF@P enables reversible Li plating/stripping on Li-metal electrodes and stable cycling performance(88.3%after 2000 cycles)in organic batteries(Li metal anode||5,5’-dimethyl-2,2’-bis-p-benzoquinone(Me2BBQ)cathode)under ambient operating conditions,highlighting the electrochemical viability of the Li-COF@P for all-solid-state organic batteries.

Critical current degradation in an epoxy-impregnated rare-earth Ba_(2)Cu_(3)O_(7-x)coated conductor caused by damage during a quench

High-temperature superconducting(HTS)rare-earth Ba_(2)Cu_(3)O_(7-x)(REBCO)coated conductors(CCs)have significant potential in high-current and high-field applications.However,owing to the weak interface strength of the laminated composite REBCO CCs,the damage induced by the thermal mismatch stress under a combination of epoxy impregnation,cooling,and quenching can cause premature degradation of the critical current.In this study,a three-dimensional(3D)electromagnetic-thermal-mechanical model based on the H-formulation and cohesive zone model(CZM)is developed to study the critical current degradation characteristics in an epoxy-impregnated REBCO CC caused by the damage during a quench.The temperature variation,critical current degradation of the REBCO CC,and its degradation onset temperature calculated by the numerical model are in agreement with the experimental data taken from the literature.The delamination of the REBCO CC predicted by the numerical model is consistent with the experimental result.The numerical results also indicate that the shear stress is the main contributor to the damage propagation inside the REBCO CC.The premature degradation of the critical current during a quench is closely related to the interface shear strength inside the REBCO CC.Finally,the effects of the coefficient of thermal expansion(CTE)of the epoxy resin,thickness of the substrate,and substrate material on the critical current degradation characteristics of the epoxy-impregnated REBCO CC during a quench are also discussed.These results help us understand the relationship between the current-carrying degradation and damage in the HTS applications.

基于人工磁导体的低剖面高增益宽带天线

提出一种基于人工磁导体(Artificial Magnetic Conductor, AMC)的高增益宽带天线,该天线由一个AMC超表面和一个微带贴片天线组成。利用AMC的同相反射特性,将天线的后向辐射反射与前向辐射叠加,从而提升了天线的增益。天线的整体尺寸为0.6λ_(0)×0.6λ_(0)×0.12λ_(0) (λ_(0)为天线谐振频率对应的波长)。测试结果表明,在4.55~6.1 GHz (27.7%)的工作频段内,天线的峰值增益达到8.4 dB。与利用理想电导体(Perfect Electric Conductor, PEC)提升增益的方法相比,其剖面从0.37λ_(0)降低到0.12λ_(0)。该天线剖面低、尺寸小、增益高、成本低廉,可以应用于WLAN波段通信。

高精度椭圆阵列电流传感器误差优化算法研究

为了减小由于矩形导体偏心和倾斜导致的传感器测量误差,实现电流高精度测量,提出一种基于灰狼优化(GWO)算法优化反向传播(BP)神经网络的椭圆阵列霍尔电流传感器误差优化方案。首先,基于三维磁场模型确定导体偏心参数和倾斜参数,并进行电流反演,得出电流积分模型;然后,使用BP神经网络估计导体参数,并引入GWO算法优化BP神经网络的初始权值和阈值,构建导体状态参数估计模型,实现偏心与倾斜误差优化;最后,搭建实验平台,对本文提出的误差优化方案进行验证。实验结果表明:本文提出误差优化方案能够精确估计导体状态参数,进而有效减小偏心误差和倾斜误差,导体X向偏心产生的电流误差减小65.07%,Y向偏心产生的电流误差减小45.74%,偏离Z轴产生的倾斜电流误差减小76.15%。

适用于硅胶基材的可拉伸导电油墨的研究进展

印刷电子正逐渐从柔性电子向可拉伸电子方向发展,开发平面的可拉伸导体对可拉伸电子具有重要的意义。快速制备柔软的但有一定强度的可拉伸导体的方法是将导电材料与弹性聚合物复合形成导电油墨并印刷在弹性基材上。基于硅胶的弹性基材具有良好的生物相容性、热稳定性和化学稳定性,弹性接近皮肤,被用于表皮电子器件、智能软体机器人、可穿戴电子器件等。鉴于硅胶表面非极性的特性,为实现印刷的墨层与硅胶表面之间高的粘附牢度,对印刷油墨提出较高要求。本文重点介绍了两类用于硅胶基材的可拉伸导电油墨且将其进行对比,并分析了印刷后图案的后处理方式对拉伸性的影响。指出采用非极性连结料并选择相容性好的导电组分制备导电油墨是硅胶基材上印刷可拉伸电极的关键;复合不同导电组分、在墨层中引入多孔结构、氙灯烧结有利于提升硅胶基可拉伸电子器件的性能。

中温质子导体电解池型氨合成反应器研究

当前传统的氨气规模化生产造成了大量的能源消耗和碳排放,需要寻找一种低碳的技术途径,因此,绿氨合成成为“双碳”背景下的重要研究课题之一。质子导体型陶瓷电解池(Protonic Ceramic Electrolysis Cells,PCECs)可采用可再生电力电解水蒸气原位制氢,有望用作绿氨合成反应器。本研究采用Ni-BaCe_(0.7)Zr_(0.1)Y_(0.2)O_(3)−δ(BCZY)多孔复合陶瓷,研究了质子导体燃料电极的材料特性和合成氨反应条件,650℃时获得了1.04×10^(−10) mol/(s·cm^(2))合成氨速率。基于以上结果,以等静压-浸渍-共烧的工艺方法制备了活性面积达到10 cm^(2)的管式质子导体型电解池。其在650℃,1.4 V电压下获得3 A电解电流,并在合成氨工况条件下稳定运行;管式电池原位产氢能够用于Ni-BCZY燃料电极上的合成氨过程并显著促进了氨产率的提升,合成氨速率达到7.02×10^(−10) mol/(s·cm^(2))。200 h的测试结果表明,电解池的电化学性能与合成氨速率均表现出良好的稳定性,显示了作为绿氨合成反应器的潜力。

混合导体膜反应器用于甲烷部分氧化制合成气的研究

为解决甲烷部分氧化反应制合成气中的过度氧化问题,通过引入混合导体透氧膜反应器与甲烷部分氧化反应的耦合,提高合成气的选择性。以Ni/γ-Al_(2)O_(3)和Ni/SBA-15为催化剂对膜反应器性能进行测试。结果表明,Ni/SBA-15催化剂的介孔结构在测试后坍塌,性能下降。而在950℃下,以Ni/γ-Al_(2)O_(3)为催化剂的膜反应器甲烷转化率达92%,CO选择性高达99%。经500 min稳定性测试,膜反应器展现出良好的甲烷转化率和化学稳定性。

基于驱动导体环的板件电磁成形电磁力分布与成形效果研究

为实现电磁成形中电磁力的可控加载,提升板件成形效果,该文提出一种基于驱动导体环的板件电磁成形技术。该技术在板件与驱动线圈之间引入一驱动环,通过改变驱动环的材料参数与几何参数实现电磁力的调控。基于特定的AA1060铝板(铝板半径70 mm,铝板成形区域半径50 mm)进行了仿真研究。仿真数据表明,驱动导体环的材质和几何结构的变化可以改变感应涡流从而实现电磁力的调控。与传统板件电磁成形相比,基于驱动导体环的板件电磁成形均匀成形范围Dr提高了1.61倍。在仿真基础上,通过驱动导体环板件电磁成形实验验证了仿真模型的可靠性。综上所述,基于驱动导体环的电磁成形技术能有效提高板件成形的均匀度。

A Top Level Bundle Conductors Laboratory Built in China

This paper introduces the key laboratory on bundle conductors for high voltage overhead lines built byElectric Power Construction Research Institute under the State Power Corporation of China. It consists of 4 sub-laboratories, namely the Aeolian Vibration Lab, Spacer Vibration Lab, Conductor Fatigue Lab and Conductor CreepageLab. The paper introduces also laboratory’s facilities, functions and some experimental results.[

计及树障类型的绝缘导线电场分布特性及放电烧蚀机制

线路树障发生后线路重合闸难以成功,极容易造成线路停运,国内外已发生了多起因树障而导致的电网大停电事故,但不同树障类型的绝缘导线电场分布特性及放电机制尚不清晰。因此,本文基于有限元理论,建立不同树障类型的绝缘导线静电场模型,根据所得电场分布及气固放电理论揭示树障放电烧蚀机制。结果表明:绝缘导线树障类型主要分为4类,单侧楔形刺入缺陷、平切缺陷、双楔形刺入缺陷、木刺与缺陷临界接触的树障-导线类型;电场在树障缺陷处均发生了畸变,楔形刺入缺陷可导致树枝-绝缘导线处发生气体击穿放电,对绝缘导线表面及树枝的烧蚀危害最大。缺陷处场强受缺陷程度及气隙的影响,木刺深入绝缘层的最大电场强度比仅刺入屏蔽层的增加了2.64倍;风吹扰动导致木刺与缺陷临界接触产生气隙,其电场相比无气隙情况下的5.65kV/mm增加了2.54倍。研究结果对不同类型树障防御方法提供理论依据,避免了无差别砍伐树木的弊端。

Heat Resisting Mechanism of Heat-Resisting Aluminum Alloy Conductor and Its Application in Transmission Line

In this paper the heat withstanding mechanism of heat-resisting aluminum alloy conductor is discussed, the types and performance of the conductor and its application on transmission lines are analyzed and introduced, and suggestions on accelerating exploitation and application of the conductor are put forward.

利用新型导线警示灯提升城市道路交通安全性能的研究

本文首先介绍了新型导线警示灯的基本结构和工作原理,以及其技术特点和优势;其次提出了城市道路交通安全性能的评估指标,包括交通事故统计和分析、交通流量和拥堵状况评估、驾驶员行为评估以及道路设施评估;再次探讨了新型导线警示灯在这些方面的应用;最后通过案例分析,对新型导线警示灯的应用前景进行展望,以期提升城市道路交通安全性能,为城市交通运输系统的高效运行提供有力支持。

Conductive Mechanism of Organic Conductor

Organic conductor is a kind of organic compound which has special electronic and magnetic properties. The research of the organic compounds has received considerable attention because of their potential applications in many areas. The molecular conductive units are theoretically investigated as well as their energy gap and charge distribution. The relationship of conductivity and micro mechanism is discussed.

Investigation of La_(9.33)Si_6O_(26) Oxygen Ionic Conductor

La9.335i6O26 oxygen ionic conductor was synthesized by solid state reaction method. Its structure was deter- mined by single-crystal X-ray diffraction analysis at room temperature. The results showed that La9.33Si6O26 oxide has the apatite structure with space group P63/m. AC impedance measurements indicated that the oxides sintered in nitrogen have much higher conductivity than those sintered in air. The effects of grain boundaries on the conductivity were discussed.

Development of proton-conducting membrane based on incorporating a proton conductor 1,2,4-triazolium methanesulfonate into the Nafion membrane

In this paper, 1,2,4-triazolium methanesulfonate （C_2H_4N_3^＋-CH_3SO_3^-, [Tri][MS]）, an ionic conductor, was successfully synthesized. It exhibited high ionic conductivity of 18.60 mS·cm^-1 at 140 ℃ and reached up to 36.51 mS·cm^-1 at 190 ℃. [Tri][MS] was first applied to modify Nation membrane to fabricate [Tri][MS]/Nafion membrane by impregnation method at 150 ℃. The prepared composite membrane showed high thermal stability with decomposed temperature above 200 ℃ in air atmosphere. In addition, the membrane indicated good ionic conductivity with 3.67 mS·cm^-1 at 140 ℃ and reached up to 13.23 mS·cm^-1 at 180 ℃. The structure of the [Tri][MS] and the composite membrane were characterized by FTIR and the compatibility of [Tri][MS] and Pt/C catalyst was studied by a cyclic voltammetry （CV） method. Besides, the [Tri][MS]/Nafion membrane （thickness of 65 μm） was evaluated with single fuel cell at high temperature and without humidification. The highest power density of [Tri][MS]/Nafion membrane was 3.20 mW·cm^-2 at 140 ℃ and 4.90 mW·cm^-2 at 150 ℃, which was much higher than that of Nation membrane.

Current Sharing Temperature Test and Simulation with GANDALF Code for ITER PF2 Conductor Sample

Cable-in-conduit conductor （CICC） conductor sample of the PF2 coil for ITER was tested in the SULTAN facility. According to the test results, the CICC conductor sample exhibited a stable performance regarding the current sharing temperature. Under the typical operational conditions of a current of 45 kA, a magnetic field of 4 T and a temperature of 5 K for PF2, the test result for the conductor current sharing temperature is 6.71 K, with a temperature margin of 1.71 K. For a comparison thermal-hydraulic analysis of the PF2 conductor was carried out using GANDALF code in a 1-D model, and the result is consistent with the test one.

Theoretical analysis for the mechanical behavior caused by an electromagnetic cycle in ITER Nb3Sn cable-in-conduit conductors

The central solenoid（CS）is one of the key components of the International Thermonuclear Experimental Reactor（ITER）tokamak and which is often considered as the heart of this fusion reactor.This solenoid will be built by using Nb3Sn cablein-conduit conductors（CICC）,capable of generating a 13 T magnetic field.In order to assess the performance of the Nb3Sn CICC in nearly the ITER condition,many short samples have been evaluated at the SULTAN test facility（the background magnetic field is of 10.85 T with the uniform length of 400 mm at 1%homogeneity）in Centre de Recherches en Physique des Plasma（CRPP）.It is found that the samples with pseudo-long twist pitch（including baseline specimens）show a significant degradation in the current-sharing temperature（Tcs）,while the qualification tests of all short twist pitch（STP）samples,which show no degradation versus electromagnetic cycling,even exhibits an increase of Tcs.This behavior was perfectly reproduced in the coil experiments at the central solenoid model coil（CSMC）facility last year.In this paper,the complex structure of the Nb3Sn CICC would be simplified into a wire rope consisting of six petals and a cooling spiral.An analytical formula for the Tcs behavior as a function of the axial strain of the cable is presented.Based on this,the effects of twist pitch,axial and transverse stiffness,thermal mismatch,cycling number,magnetic distribution,etc.,on the axial strain are discussed systematically.The calculated Tcs behavior with cycle number show consistency with the previous experimental results qualitatively and quantitatively.Lastly,we focus on the relationship between Tcs and axial strain of the cable,and we conclude that the Tcs behavior caused by electromagnetic cycles is determined by the cable axial strain.Once the cable is in a compression situation,this compression strain and its accumulation would lead to the Tcs degradation.The experimental observation of the Tcs enhancement in the CS STP samples should be considered as a contribution of the shorter length of the high field zone in SULTAN and CSMC devices,as well as the tight cable structure.

Simulation study of a magnetocardiogram based on a virtual heart model:effect of a cardiac equivalent source and a volume conductor

In this paper, we present a magnetocardiogram （MCG） simulation study using the boundary element method （BEM） and based on the virtual heart model and the realistic human volume conductor model. The different contributions of cardiac equivalent source models and volume conductor models to the MCG are deeply and comprehensively investigated. The single dipole source model, the multiple dipoles source model and the equivalent double layer （EDL） source model are analysed and compared with the cardiac equivalent source models. Meanwhile, the effect of the volume conductor model on the MCG combined with these cardiac equivalent sources is investigated. The simulation results demonstrate that the cardiac electrophysiological information will be partly missed when only the single dipole source is taken, while the EDL source is a good option for MCG simulation and the effect of the volume conductor is smallest for the EDL source. Therefore, the EDL source is suitable for the study of MCG forward and inverse problems, and more attention should be paid to it in future MCG studies.

Corrosion Prevention of the Generator Stator Hollow Copper Conductor and Water Quality Adjustment of Its Internal Cooling Water

On the basis of expounding the corrosion mechanism of the stator hollow copper conductor in the water-cooling generator, methods of preventing corrosion of the stator hollow copper conductor in the wa-ter-cooling generator through adjusting water quality of its cooling water have been proposed. For internal water cooling systems which are airtight, the corrosion of the hollow copper conductor can be prevented through keeping foreign oxygen and carbon dioxide from entering the system, and the amount of oxygen in the internal water can be lowered by blowing high purity nitrogen. For systems not airtight, the corrosion of the hollow copper conductor can be inhibited through lowering the amount of oxygen to some extent by sealing and increasing pH value by processing part of cooling water with bypass small flow sodium-type mix-bed.