薄膜介质层绕式Blumlein线理论与实验研究

对薄膜介质层绕式Blumlein线的特性参数进行了理论分析。采用Pspice软件对电路模型进行了计算,分析了开关电感、寄生电阻对负载输出波形的影响。结果表明:开关电感的存在使得负载波形前沿变缓,后延波形扭曲变差,寄生电阻会影响负载的电压输出效率。采用模拟软件对传输线中的电磁场分布进行了计算,结果表明薄电极边缘场畸变以及折叠弯曲部分的场变化是绝缘介质耐压必须考虑的因素。基于此理论分析,设计制作了一种新型薄膜介质Blumlein线,绝缘材料为聚酯薄膜,单层薄膜厚100μm,电极为厚50μm的铜皮,单元模块设计耐压50 kV。进行了三级模块串联叠加实验,充电25 kV,匹配负载输出60 kV,脉冲上升沿80 ns,脉冲宽度200 ns。     

Robustly topological mixing of Kan's map

In 1994, I. Kan constructed a smooth map on the annulus admitting two physical measures, whose basins are intermingled. In this paper, we prove that Kan's map is $C^2$ robustly topologically mixing.     

美国船舶电台管理模式简介

为确保水上无线电通信安全,我国应加强对船舶电台的管理。本文以美国FCC为例,介绍了发达国家中较具代表性的船舶电台管理模式。     

Effect of Ge-GeO2 co-doping on non-ohmic behaviour of TiO2-V2O5-Y2O3 varistor ceramics

An investigation was made into the effect of doping with the elemental crystal Ge or/and GeO₂ on the TiO₂-V₂O₅-Y₂O₃ varistor ceramics. The result shows that as the doping contents of V₂O₅ and Y₂O₃ are 0.5 mol%, respectively, co-doping with 0.3 mol% Ge and 0.9 mol% GeO₂ makes the highest α value (α = 12.8), the lowest breakdown voltage V_1mA (V_1mA = 15.8 V/mm) and the highest grain boundary barrier Φ_B (Φ_B = 1.48 eV), which is remarkably superior to the TiO₂-V₂O₅-Y₂O₃ varistor ceramics undoped with Ge and GeO₂ and mono-doped with Ge or GeO₂. The TiO₂-V₂O₅-Y₂O₃-Ge-GeO₂ ceramic has the prospect of becoming a novel varistor ceramic with excellent electrical properties.     

基于神经网络的光伏发电功率预测不良数据处理的研究

光伏发电系统历史发电功率数据的真实可靠是光伏发电系统发电功率预测的基础,而在光伏发电系统运行或数据采集、测量、传输、转换等环节出现故障时会导致历史数据中含有不良数据。本论文提出采用小波分析中的信号奇异点检测法对不良数据进行剔除,并采用神经网络的时间序列预测模型对剔除后的数据进行重构,从而达到检测并消除不良数据的目的,为光伏发电系统发电功率预测提供能反应其变化规律的真实历史信息。     

Design of Sensitive Biocompatible Quantum‐Dots Embedded in Mesoporous Silica Microspheres for the Quantitative Immunoassay of Human Immunodeficiency Virus‐1 Antibodies

A novel sandwich‐type electrochemiluminescence (ECL) immunosensor was developed to enable the sensitive detection of HIV‐1 antibodies. This system incorporated mesoporous silica (mSiO₂) complexed with quantum dots (QDs) and nano‐gold particles, which were assembled to enhance signal detection. Magnetic beads were used by immobilizing the secondary anti‐IgG antibody. This was first employed to capture HIV‐1 antibody (Ab) to form a Fe₃O₄/anti‐IgG/Ab complex. A high loading and signal‐enhanced nanocomposite (hereafter referred to as Au‐mSiO₂‐CdTe) was used as a HIV‐1 antigen label. The Au‐mSiO₂‐CdTe nanocomposite was conjugated with the Fe₃O₄/anti‐IgG/Ab complex to form an immunocomplex (hereafter referred to as Fe₃O₄/anti‐IgG/Ab/HIV‐1/CdTe‐mSiO₂‐Au). This complex could be further separated by an external magnetic field to produce ECL signals. Due to the large specific surface area and pore volume of mSiO₂, the loading of the CdTe QDs was markedly increased. Thus, the loaded QDs released a powerful chemiluminescent signal with a concordantly increased sensitivity of the immunosensor. The immunosensor was highly sensitive, and displayed a linear range of responses for HIV‐1 antibody across a dilution range of 1 : 1500 through 1 : 50 with the detection limit of 1 : 4500. The immunoassay can be a promising candidate in early diagnosis of HIV infection.     

Oxidation of Aliphatic α,β-Unsaturated Aldimines to Amides Specifically by Oxone with AlCl3

α,β-Unsaturated aldimines were specifically oxidized to amides with Oxone in the presence of AlCl₃ as a Lewis acid in CH₂Cl₂. No migration of aryl group occurred in the rearrangement reaction.     

Progress of Jinping Underground laboratory for Nuclear Astrophysics (JUNA)

Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of~(25)Mg(p,γ)~(26)Al,~(19)F(p,α)~(16)O,~(13)C(α,n)~(16)O and ~(12)C(α,γ)~(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.     

Trends in ultrashort and ultrahigh power laser pulses based on optical parametric chirped pulse amplification

Since the proof-of-principle demonstration of optical parametric amplification to efficiently amplify chirped laser pulses in 1992,optical parametric chirped pulse amplification(OPCPA)became the most promising method for the amplification of broadband optical pulses.In the meantime,we are witnessing an exciting progress in the development of powerful and ultrashort pulse laser systems that employ chirped pulse parametric amplifiers.The output power and pulse duration of these systems have ranged from a few gigawatts to hundreds of terawatts with a potential of tens of petawatts power level.Meanwhile,the output pulse duration based on optical parametric amplification has entered the range of fewoptical-cycle field.In this paper,we overview the basic principles,trends in development,and current state of the ultrashort and laser systems based on OPCPA,respectively.     

ZIF-67 derived carbon wrapped discontinuous CoxP nanotube as anode material in high-performance Li-ion battery

Transition metal phosphides (TMPs) are prospective anode materials for lithium-ion batteries (LIBs) due to their high theoretical capacities and low redox voltages. Herein, we report a template directing method to develop a tube-sheath hybrid composing of cobalt phosphide particles encapsulated in metal organic frameworks (MOFs) derived N-doped carbon sheaths (Co_xP@NC). The utilization of directing template leads to a homogenous distribution of the subsequently formed cobalt phosphide particles, restrains the aggregation of cobalt phosphides, and thus results in the superb rate capability and cyclability. Contributable to the integrated merits of the interior downsized cobalt phosphide particles and the outer ZIF-67 derived porous carbon sheath, the volume expansion during cycling is effectively suppressed. The Co_xP@NC hybrid shows superb electrochemical performance as anode material for LIB, with good reversible capacity of 928 mAh·g^?1 after 100 cycles at 0.1 A g^?1, and high stability of 526 mAh·g^?1 after 600 cycles at 1.0 A g^?1. This work provides a route for rational design of MOF derived carbon-based anode material for LIB, which could also be applied as a promising platform in diverse field.