Research on the Customs Supervision Mechanism of Cross-border E-commerce

当前，跨境电子商务随着互联网的发展呈现飞速发展势头，既为中国贸易的发展提供了新方向，也对传统贸易模式下的政府管理体制提出了新需求和新挑战。海关作为跨境贸易的主要监管机构，在跨境电子商务监管方面扮演着非常重要的角色。从实际情况来看，我国跨境电子商务在海关监管机制建设方面存在的问题也不少。从法治的视角审视，其症结主要是跨境电子商务监管法律法规滞后、相关的配套措施欠缺及监管规程和执法尺度不统一。本文正是以这一问题作为研究对象，立足于相关理论基础，对我国跨境电子商务海关监管的问题进行深入剖析，对海关监管存在的主要问题进行客观阐述，并分析其深层次的原因。 本文由四章组成。首先是绪论，介绍了跨境电子商务...At present, with the development of Internet, the cross-border e-commerce has shown the tendency of rapid growth, having not only provided new orientation for the development of the trade in China, but also put forward to new requirement and challenge to government management system under the traditional mode. Customs, as the main authority of supervision and administration of cross-border trade,...学位：法学硕士院系专业：法学院_民商法学学号：K20110801

Simulation Design of a Terminal Short-Circuit Type Inter-Digital Band Pass Filter

基于悬置线交指滤波器通带内插入损耗比较小,具有很高的选择性和很大的带外衰减,常应用于无线电收、发接收机以及雷达通信系统中。将综合设计法和微波电路仿真软件AdS(AdVAnCEd dESIgn SySTEM)相结合,设计悬置线终端短路式交指带通滤波器。根据交指滤波器的理论得到每个杆的归一化单位长自电容和两相邻杆的归一化单位长互电容,得到滤波器的最初尺寸。并利用AdS软件建模、仿真、优化调整,最后得到该滤波器的几何参数尺寸终值。该设计方法简单,适合工程应用。Inter-digital band-pass filters based on overhanging lines are often used in wireless transceivers and radar communication systems due to their low pass-band inserting attenuation,precise selectivity and high outer-band attenuation.The combination of traditional calculation method and microwave ADS(Advanced Design System) software is used to design a filter of this type.The normalized self-capacitor,mutual capacitor of unit length and the initial value of the geometry parameters of the filter are obtained in accordance with the theory of inter-digital band-pass filter.ADS software is utilized to build model,make simulation and optimizing adjustments.This method is simple and suitable for designing filter in practice.福建省自然科学基金资助项目(2006J0410);福建省科技计划项目(2008H0032

Simulation design of terminal open-circuit type interdigital band-pass filter

基于悬置线交指带通滤波器通带内插入损耗比较小,具有很高的选择性和很大的带外衰减,常应用于无线电收、发接收机以及雷达通信系统中.将综合设计法和微波电路仿真软件AdS相结合,设计悬置线终端开路式交指带通滤波器.根据交指滤波器的理论得到每个杆的归一化单位长自电容和两相邻杆的归一化单位长互电容,得到滤波器的最初尺寸.利用AdS软件建模、仿真、优化调整,最后得到该滤波器的几何参数尺寸终值.该设计方法简单,适合工程应用.The interdigital band-pass filter based on suspended line with low pass-band insertion,precise selective and high out-band attenuation,which is often used in wireless transceiver and radar communication system.In order to design band-pass filter which hangs to place the open-circuit type of the line terminal,the traditional calculate method is combined with the microwave ADS software,the self-capacitor,mutual capacitor and the initial value of the geometry parameter of the interdigital band-pass filter are obtained according to the exact design theory of the interdigital band-pass filter.by building model,simulation,and optimization adjustment,the final value of the geometry parameter for the filter is gotten.The method is simple in designing filter and easily available for engineering applications.福建省自然科学基金资助项目(2006J0410);福建省科技计划项目(2008H0032

光子晶体光纤的特性与研究现状

光子晶体光纤(PCF)具有独特的光学特性和灵活的设计,在光通信等领域具有广阔的应用前景。文阐述了PCF的一些独特光学性质,总结了光子晶体光纤的研究成果。福建省自然科学基金资助项目(2006G0410);; 福建省自然科学基金资助项目(2006J0410

Room-temperature quantum interference in single perovskite quantum dot junctions

钙钛矿材料由于其高量子产率、载流子迁移率和独特的光致发光特性而在光电材料领域存在诸多潜在的重要应用。研究钙钛矿材料在纳米尺度下电荷输运的独特尺寸效应对钙钛矿光电器件的设计和开发具有重要的指导意义。洪文晶教授课题组基于机械可控裂结技术自主研发了具有皮米级位移调控灵敏度和飞安级电学测量精度的精密科学仪器，对南开大学李跃龙副教授团队合成的钙钛矿量子点进行了深入表征，研究工作成功将量子干涉的研究体系拓展至在光电领域具有重要应用的钙钛矿材料领域，为未来制备基于量子干涉效应的新型钙钛矿器件提供了一种全新的思路。 这一跨学科国际合作研究工作是在化学化工学院洪文晶教授、英国Lancaster 大学物理系Colin J. Lambert教授以及南开大学电子信息与光电工程学院李跃龙副教授的共同指导下完成的。化工系硕士研究生郑海宁、Lancaster University大学Songjun Hou博士、南开大学硕士研究生辛晨光为论文第一作者。博士后林禄春，博士研究生谭志冰、郑珏婷，硕士研究生蒋枫、张珑漪，本科生何文翔、李庆民等参与了论文的研究工作。刘俊扬特任副研究员、师佳副教授和萨本栋微纳米研究院杨扬副教授也参与了部分指导工作。The studies of quantum interference effects through bulk perovskite materials at the Ångstrom scale still remain as a major challenge. Herein, we provide the observation of roomtemperature quantum interference effects in metal halide perovskite quantum dots (QDs) using the mechanically controllable break junction technique. Single-QD conductance measurements reveal that there are multiple conductance peaks for the CH3NH3PbBr3 and CH3NH3PbBr2.15Cl0.85 QDs, whose displacement distributions match the lattice constant of QDs, suggesting that the gold electrodes slide through different lattice sites of the QD via Auhalogen coupling. We also observe a distinct conductance ‘jump’ at the end of the sliding process, which is further evidence that quantum interference effects dominate charge transport in these single-QD junctions. This conductance ‘jump’ is also confirmed by our theoretical calculations utilizing density functional theory combined with quantum transport theory. Our measurements and theory create a pathway to exploit quantum interference effects in quantum-controlled perovskite materials.This work was supported by the National Key R&D Program of China (2017YFA0204902, 2014DFE60170, 2018YFB1500105), the National Natural Science Foundation of China (Nos. 21673195, 21503179, 21490573, 61674084, 61874167), the Open Fund of the Key Laboratory of Optical Information Science & Technology (Nankai University) of China, the Fundamental Research Funds for the Central Universities of China (63181321, 63191414, 96173224), and the 111 Project (B16027), the Tianjin Natural Science Foundation (17JCYBJC41400), FET Open project 767187—QuIET, the EU project BAC-TO-FUEL and the UK EPSRC projects EP/N017188/1, EP/M014452/1. 该工作得到国家重点研发计划课题（2017YFA0204902）、国家自然科学基金（21673195、21503179、21490573）、厦门大学“人工智能分析引擎”双一流重大专项等项目的资助，也得到了固体表面物理化学国家重点实验室、能源材料化学协同创新中心的支持

Designable ultra-smooth ultra-thin solid-electrolyte interphases of three alkali metal anodes

该研究是在毛秉伟教授和董全峰教授共同指导下，由2014级博士生谷宇、2016级博士生王卫伟、2013级博士生李艺娟等同学通力合作的成果。泉州师范学院吴启辉教授和上海应用物理研究所樊春海研究员分别在X射线光电子能谱表征和同步辐射表征中提供了大力支持。化学化工学院郑明森副教授、颜佳伟教授、吴德印教授、iChEM研究员丁松园博士在实验和理论计算方面给予了大力帮助；田中群教授和郑南峰教授等对此工作提出了宝贵意见。 金属锂是下一代高能量密度二次电池最理想的负极材料之一。在以金属锂作为负极的电池中，锂电沉积过程中枝晶的生长及溶解过程的死锂现象是制约电池库仑效率、稳定性和安全性的重要因素，而金属锂表面的微观平整性及固态电解质界面（SEI）膜的组成和结构及由其所决定的电学和力学性质对锂电沉积和溶解行为有重要影响。 课题组所发展的电化学调控方法可进一步拓展到钠、钾碱金属负极上，形成大范围原子平整的钠、钾表面和超薄超光滑的SEI膜。特别是金属钠平面电极可在2 mA cm–2（1 mAh cm–2）100% Na DOD下稳定循环550周以上且库伦效率近100%。这一基于电化学调控的碱金属表面抛光和SEI膜构筑的方法及多尺度联合表征，为解决碱金属负极问题提供了新的思路，也为开展表面科学基础研究提供高质量的碱金属表面。【Abstract】Dendrite growth of alkali metal anodes limited their lifetime for charge/discharge cycling. Here, we report near-perfect anodes of lithium, sodium, and potassium metals achieved by electrochemical polishing, which removes microscopic defects and creates ultra-smooth ultra-thin solid-electrolyte interphase layers at metal surfaces for providing a homogeneous environment. Precise characterizations by AFM force probing with corroborative in-depth XPS profile analysis reveal that the ultra-smooth ultra-thin solid-electrolyte interphase can be designed to have alternating inorganic-rich and organic-rich/mixed multi-layered structure, which offers mechanical property of coupled rigidity and elasticity. The polished metal anodes exhibit significantly enhanced cycling stability, specifically the lithium anodes can cycle for over 200 times at a real current density of 2 mA cm-2 with 100% depth of discharge. Our work illustrates that an ultra-smooth ultra-thin solid-electrolyte interphase may be robust enough to suppress dendrite growth and thus serve as an initial layer for further improved protection of alkali metal anodes.This work was supported by the MOST projects (2015CB251102, 2012CB932902) and the NSFC projects (U1305246, 21621091, 21473147, 21533006, 21673193). 研究工作得到科技部973计划（项目批准号：2015CB251102、2012CB932902），国家自然科学基金（项目批准号：U1305246、21621091、21473147、21533006、21673193）等项目的资助

Study of Chirp and Dispersation to the Sensitivity of Optical Receiver

研究了啁啾高斯光脉冲信号对带前置放大器光接收机灵敏度的影响,进行了理论分析和数值摸拟,并以常见的g652A光纤为例研究了啁啾、群速度色散、光信号码元速率和高斯光脉冲信号的占空比对光接收机灵敏度恶化量的影响。研究表明,适当选取高斯光脉冲信号的占空比、啁啾、光接收机均衡滤波器输出的升余弦波形滚降因子的值可以提高光接收机灵敏度;群速度色散存在时,占空比的减小反而导致灵敏度恶化量的增加,说明光信号脉冲宽度并非越小越好。适当选取啁啾、群速度色散的参量β2和β3以及占空比的值可以使光接收机灵敏度的恶化量降低。该研究结果对光接收机的分析和设计有一定的指导意义。This paper discussed the effects of gauss light pulse signal with frequency chirp to the sensitivity of optical receiver with optical preamplifier.It was found that selecting appropriate value of duty cycles of gauss light pulse signal,frequency chirp and the roll-off factor of raised cosine pulse signal produced by the equalizer of optical receiver can improve the sensitivity of optical receiver.Theory analysis is done,and the corresponding curve is worked out.By taking the G.652A single-mode fiber,this paper studies the effects of chirp,GVD,bit-rate and duty cycles of gauss light pulse signal to the power penalty of the sensitivity of optical receiver.It is found that the power penalty accretes with the diminution of duty cycles.It shows that narrower light pulse length is harmful to the sensitivity of optical receiver when signal is propagated by the single-mode fiber with GVD.The result shows that selecting appropriate value of chirp、β2 and β3 of GVD and bit-rate can decrease the power penalty of the sensitivity of optical receiver.The result provides a significant reference for design of optical receiver.福建省科技计划重点项目(2008H0032

Simulation Design of Overhanging Line Terminal Short-circuit Type Interdigital Pass Filter

将综合设计法和先进的微波电路仿真软件AdS相结合,设计了悬置线终端短路式交指带通滤波器,并进行建模、仿真、优化调整,最后得到该滤波器的几何参数尺寸终值,仿真结果表明该滤波器满足设计指标要求.This paper combines traditional calculation method and the advanced microwave circuit software ADS,and finally devised band-pass filter which hangs to place the short-circuit type of the line terminal.According to its model building,simulation,and optimization adjustment,the final value of the geometry parameter for this filter was obtained.The result of simulation is suit for designing targets.福建省自然科学基金资助项目(2006G0410;2006J0410

大孔拟薄水铝石和γ-Al_2O_3载体制备研究进展

γ-Al_2O_3作为催化剂载体在炼油领域具有广泛应用。随着原油资源的重、劣质化,重油加工过程,如固定床渣油加氢、重油催化裂化,对其催化剂载体均提出了大孔要求以满足重油大分子在催化剂孔道内的传质扩散所需,因此,制备适用于重油加工的大孔γ-Al_2O_3载体受到越来越多的关注。γ-Al_2O_3性质主要决定于其前驱物拟薄水铝石,本工作综述了大孔拟薄水铝石的主要工业制备工艺,包括沉淀法、醇铝水解法等,并介绍了基于上述工艺所进行的γ-Al_2O_3载体扩孔研究,如p H摆动扩孔、添加扩孔剂扩孔及水热处理扩孔等。最后,展望了今后大孔拟薄水铝石和γ-Al_2O_3载体制备研究的重点和发展方向