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用于超快电子器件的全通型波导 Article

Desong Wang, Ke Wu

《工程（英文）》 2023年 第30卷 第11期   页码 49-54 doi: 10.1016/j.eng.2023.04.005

摘要：

Ultrashort pulse transmission has been recognized as a primary problem that fundamentally hinders the development of ultrafast electronics beyond the current nanosecond timescale. This requires a transmission line or waveguide that exhibits an all-pass frequency behavior for the transmitted ultrashort pulse signals. However, this type of waveguiding structure has not yet been practically developed; groundbreaking innovations and advances in signal transmission technology are urgently required to address this scenario. Herein, we present a synthesized all-pass waveguide that demonstrates record guided-wave controlling capabilities, including eigenmode reshaping, polarization rotation, loss reduction, and dispersion improvement. We experimentally developed two waveguides for use in ultrabroad frequency ranges (direct current (DC)-to-millimeter-wave and DC-to-terahertz). Our results suggest that the waveguides can efficiently transmit picosecond electrical pulses while maintaining signal integrity. This waveguide technology is an important breakthrough in the evolution of ultrafast electronics, providing a path towards frequency-engineered ultrashort pulses for low-loss and low-dispersion transmissions.

关键词： All-pass waveguide     Ultrashort pulse     Picosecond transmission     Ultrafast electronics     Terahertz technology     Mode-selective transmission line    

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Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

《能源前沿（英文）》 2016年 第10卷 第2期   页码 213-226 doi: 10.1007/s11708-016-0398-6

摘要： There is a considerable number of works devoted to electrical characteristics of grounding. These characteristics are important in general. However, in application to grounding of transmission line towers they are not enough to determine what grounding construction is preferable in some particular case, because these characteristics are calculated or measured apart from the grounded object, and only limited number of current (or voltage) source waveforms is used. This paper indicates reasons in favor of the fact that to choose the optimum design of grounding, the calculation model should include the tower as it is. The probability of back flashover, which provides both qualitative and quantitative estimate of the grounding structure efficiency, can be taken as the criterion for the grounding design. The insulation flashover probability is calculated on the basis of engineering method, which evaluates breakdown strength of insulation for nonstandard waveshapes, and probability data on lightning currents. Different approaches are examined for identifying the back flashover probability, as not only amplitudes but also other parameters can be taken into account. Finite-difference time-domain method is used for calculations of transients. It is found that lightning current waveform can greatly influence calculated back flashover probability value.

关键词： grounding     transmission line tower     back flashover probability     FDTD method    

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Reliability analysis of urban gas transmission and distribution system based on FMEA and correlation

Su LI,Weiguo ZHOU

《能源前沿（英文）》 2014年 第8卷 第4期   页码 443-448 doi: 10.1007/s11708-014-0336-4

摘要： In order to improve the safety management of urban gas transmission and distribution system, failure mode and effects analysis (FMEA) was used to construct the reliability analysis system of the pipeline network. To solve the problem of subjectivity and uncertainty of the multi-expert decision making, the correlation operator was introduced into the calculation of the risk priority number (RPN). Using FMEA along with weight analysis and expert investigation approach, the FMEA evaluation table was given, including five failure modes, risk priority numbers, failure causes and effects, as well as corrective actions. The results show that correlation operator can directly process the linguistic terms and quantify the priority of the risks.

关键词： gas transmission and distribution system     risk evaluation     reliability analysis     failure mode and effects analysis (FMEA)     correlation operator    

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基于ANSYS的汽车变速器检测试验台架有限元分析

刘鹏浩,付胜,朱晓民

《中国工程科学》 2014年 第16卷 第8期   页码 74-78

摘要：

本文运用Solidworks 软件对汽车变速器检测试验台架进行了三维建模，通过ANSYS软件进行瞬态分析和模态分析，得到了汽车变速器检测试验台架的应力云图，识别出试验台架结构的模态参数，得出台架的固有频率和振型特征。为进一步研究汽车变速器检测试验台振动、疲劳和噪声等奠定了基础，也为汽车变速器检测试验台架结构的优化设计提供了参考依据。

关键词： 变速器检测试验台     ANSYS     有限元分析     瞬态分析     模态分析    

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基于三线耦合结构的具有灵活带宽的紧凑型平衡式输入无反射带通滤波器 Research Article

朱雅慧1,2,蔡璟1,2,秦伟1,2,杨汶汶1,2,陈建新1,2

《信息与电子工程前沿（英文）》 2023年 第24卷 第2期   页码 314-326 doi: 10.1631/FITEE.2200261

摘要： 本文提出一种基于三线耦合结构的具有灵活带宽的紧凑型平衡式输入无反射带通滤波器。在差模模式下，带通响应由三线耦合结构实现，同时三线耦合结构的输入耦合馈线被输入吸收网络复用。带通滤波部分和吸收部分实现了良好的融合，有效地减小了电路尺寸，并且两部分的带宽独立可控，进而使得该滤波器的差模响应带宽具有灵活可控的特性。此外，首次对两部分的带宽比进行详细分析,以获得通带平坦度与无反射性能的良好折衷。因此，该协同设计的输入无反射差模带通响应具有易于优化的特点。同时，输入端的吸收网络还实现了宽频带内的共模噪声吸收。为了验证该设计方法，设计了一款尺寸为0.52λ×0.36λ的平衡式输入无反射滤波器，测量范围为0–7.0 GHz。测得差模响应的中心频率为2.45 GHz，3 dB相对带宽为31.4%。实测和仿真结果展现了良好的一致性，并且该滤波器具有0.43 dB的低插入损耗、较宽的差模上阻带（超过20 dB的抑制水平至2.72倍频）以及宽带的差模无反射和共模噪声吸收（吸收相对带宽为285.7%）等优点。

关键词： 输入无反射滤波器；平衡式带通滤波器；差模；共模；三线耦合结构    

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川气东送建设工程综述

曹耀峰

《中国工程科学》 2010年 第12卷 第10期   页码 4-8

摘要：

川气东送建设工程是我国首次对超深高酸性天然气进行大规模勘探开发、集中净化处理、长距离管道输送、综合市场开发及利用的系统工程，具有特大型、超复杂、高风险、高难度的特点。在简要介绍工程的开发背景、建设规模，分析其面临主要技术与管理难点的基础上，系统叙述了建设工程主要的管理与技术创新系列成果、建设理念及所取得的成就。建设工程所形成的超深高酸性气田勘探开发配套系列技术和特大型综合油气项目建设管理经验，必将为同类气田的建设提供有益的借鉴。

关键词： 高酸性气田     技术集成与创新     管理创新与运行模式     大型天然气净化厂    

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Acoustic fault signal extraction via the line-defect phononic crystals

《机械工程前沿（英文）》 2022年 第17卷 第1期   页码 10-10 doi: 10.1007/s11465-021-0666-y

摘要： Rotating machine fault signal extraction becomes increasingly important in practical engineering applications. However, fault signals with low signal-to-noise ratios (SNRs) are difficult to extract, especially at the early stage of fault diagnosis. In this paper, 2D line-defect phononic crystals (PCs) consisting of periodic acrylic tubes with slit are proposed for weak signal detection. The defect band, namely, the formed resonance band of line-defect PCs enables the incident acoustic wave at the resonance frequency to be trapped and enhanced at the resonance cavity. The noise can be filtered by the band gap. As a result, fault signals with high SNRs can be obtained for fault feature extraction. The effectiveness of weak harmonic and periodic impulse signal detection via line-defect PCs are investigated in numerical and experimental studies. All the numerical and experimental results indicate that line-defect PCs can be well used for extracting weak harmonic and periodic impulse signals. This work will provide potential for extracting weak signals in many practical engineering applications.

关键词： phononic crystals     line-defect     fault signal extraction     acoustic enhancement    

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Calculations of narrow-band transimissities and the Planck mean absorption coefficients of real gases using line-by-line

Huaqiang CHU, Mingyan GU, Huaichun ZHOU, Fengshan LIU

《能源前沿（英文）》 2014年 第8卷 第1期   页码 41-48 doi: 10.1007/s11708-013-0292-4

摘要： Narrow-band transmissivities in the spectral range of 150 to 9300 cm and at a uniform resolution of 25 cm were calculated using the statistical narrow-band (SNB) model with the band parameters of Soufiani and Taine, the more recent parameters of André and Vaillon, and the line-by-line (LBL) method along with the HITEMP-2010 spectroscopic database. Calculations of narrow-band transmissivity were conducted for gas columns of different lengths and containing different isothermal and non-isothermal CO -H O-N mixtures at 1 atm. Narrow-band transmissivities calculated by the SNB model are in large relative error at many bands. The more recent SNB model parameters of André and Vaillon are more accurate than the earlier parameters of Soufiani and Taine. The Planck mean absorption coefficients of CO , H O, CO, and CH in the temperature range of 300 to 2500 K were calculated using the LBL method and different versions of the high resolution transmission (HITRAN) and high-temperature spectroscopic absorption parameters (HITEMP) spectroscopic databases. The SNB model was also used to calculate the Planck mean absorption coefficients of these four radiating gases. The LBL results of the Planck mean absorption coefficient were compared with the classical results of Tien and those from the SNB model.

关键词： transimissity     HITEMP     HITRAN     Planck mean absorption coefficients    

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Recent advances in selective acetylene hydrogenation using palladium containing catalysts

Alan J. McCue, James A. Anderson

《化学科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 142-153 doi: 10.1007/s11705-015-1516-4

摘要： Recent advances with Pd containing catalysts for the selective hydrogenation of acetylene are described. The overview classifies enhancement of catalytic properties for monometallic and bimetallic Pd catalysts. Activity/selectivity of Pd catalysts can be modified by controlling particle shape/morphology or immobilisation on a support which interacts strongly with Pd particles. In both cases enhanced ethylene selectivity is generally associated with modifying ethylene adsorption strength and/or changes to hydride formation. Inorganic and organic selectivity modifiers (i.e., species adsorbed onto Pd particle surface) have also been shown to enhance ethylene selectivity. Inorganic modifiers such as TiO change Pd ensemble size and modify ethylene adsorption strength whereas organic modifiers such as diphenylsulfide are thought to create a surface template effect which favours acetylene adsorption with respect to ethylene. A number of metals and synthetic approaches have been explored to prepare Pd bimetallic catalysts. Examples where enhanced selectivity is observed are generally associated with decreased Pd ensemble size and/or hindering of the ease with which an unselective hydride phase is formed for Pd. A final class of bimetallic catalysts are discussed where Pd is not thought to be the primary reaction site but merely acts as a site where hydrogen dissociation and spillover occurs onto a second metal (Cu or Au) where the reaction takes place more selectively.

关键词： acetylene     ethylene     selective hydrogenation     palladium     bimetallic    

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Preparation of polysulfone-based block copolymer ultrafiltration membranes by selective swelling and

《化学科学与工程前沿（英文）》 2022年 第16卷 第5期   页码 745-754 doi: 10.1007/s11705-021-2038-x

摘要： Selective swelling of block copolymers of polysulfone-b-poly(ethylene glycol) is an emerging strategy to prepare new types of polysulfone ultrafiltration membranes. Herein, we prepared nanoporous polysulfone-b-poly(ethylene glycol) ultrafiltration membranes by selective swelling and further promoted their porosity and ultrafiltration performances by using CaCO3 nanoparticles as the sacrificial nanofillers. Different contents of CaCO3 nanoparticles were doped into the solution of polysulfone-b-poly(ethylene glycol), and thus obtained suspensions were used to prepare both self-supported and bi-layered composite structures. Selective swelling was performed on the obtained block copolymer structures in the solvent pair of ethanol/acetone, producing nanoporous membranes with poly(ethylene glycol) lined along pore walls. The CaCO3 nanoparticles dispersed in polysulfone-b-poly(ethylene glycol) were subsequently etched away by hydrochloric acid and the spaces initially occupied by CaCO3 provided extra pores to the block copolymer layers. The porosity of the membranes was increased with increasing CaCO3 content up to 41%, but further increase in the CaCO3 content led to partial collapse of the membrane. The sacrificial CaCO3 particles provided extra pores and enhanced the connectivity between adjacent pores. Consequently, the membranes prepared under optimized conditions exhibited up to 80% increase in water permeance with slight decrease in rejection compared to neat membranes without the use of sacrificial CaCO3 particles.

关键词： block copolymers     selective swelling     ultrafiltration     CaCO3 nanoparticles     sacrificial nanofillers    

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Recent transmission of Mycobacterium tuberculosis in China: the implication of molecular epidemiology

null

《医学前沿（英文）》 2018年 第12卷 第1期   页码 76-83 doi: 10.1007/s11684-017-0609-5

摘要：

Tuberculosis (TB) has remained an ongoing concern in China. The national scale-up of the Directly Observed Treatment, Short Course (DOTS) program has accelerated the fight against TB in China. Nevertheless, many challenges still remain, including the spread of drug-resistant strains, high disease burden in rural areas, and enormous rural-to-urban migrations. Whether incident active TB represents recent transmission or endogenous reactivation has helped to prioritize the strategies for TB control. Evidence from molecular epidemiology studies has delineated the recent transmission of ( ) strains in many settings. However, the transmission patterns of TB in most areas of China are still not clear. Studies carried out to date could not capture the real burden of recent transmission of the disease in China because of the retrospective study design, incomplete sampling, and use of low-resolution genotyping methods. We reviewed the implementations of molecular epidemiology of TB in China, the estimated disease burden due to recent transmission of strains, the primary transmission of drug-resistant TB, and the evaluation of a feasible genotyping method of strains in circulation.

关键词： tuberculosis     recent transmission     molecular epidemiology     China    

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Pareto lexicographic α-robust approach and its application in robust multi objective assembly line balancing

null

《机械工程前沿（英文）》 2014年 第9卷 第3期   页码 257-264 doi: 10.1007/s11465-014-0294-x

摘要：

Robustness in most of the literature is associated with min-max or min-max regret criteria. However, these criteria of robustness are conservative and therefore recently new criteria called, lexicographic α-robust method has been introduced in literature which defines the robust solution as a set of solutions whose quality or jth largest cost is not worse than the best possible jth largest cost in all scenarios. These criteria might be significant for robust optimization of single objective optimization problems. However, in real optimization problems, two or more than two conflicting objectives are desired to optimize concurrently and solution of multi objective optimization problems exists in the form of a set of solutions called Pareto solutions and from these solutions it might be difficult to decide which Pareto solution can satisfy min-max, min-max regret or lexicographic α-robust criteria by considering multiple objectives simultaneously. Therefore, lexicographic α-robust method which is a recently introduced method in literature is extended in the current research for Pareto solutions. The proposed method called Pareto lexicographic α-robust approach can define Pareto lexicographic α-robust solutions from different scenarios by considering multiple objectives simultaneously. A simple example and an application of the proposed method on a simple problem of multi objective optimization of simple assembly line balancing problem with task time uncertainty is presented to get their robust solutions. The presented method can be significant to implement on different multi objective robust optimization problems containing uncertainty.

关键词： Pareto     lexicographic α-robust     assembly line balancing    

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Highly efficient and selective removal of vanadium from tungstate solutions by microbubble floating-extraction

《化学科学与工程前沿（英文）》 2023年 第17卷 第5期   页码 581-593 doi: 10.1007/s11705-022-2235-2

摘要： Selective separation of dissolved tungsten and vanadium is of great significance for the utilization of the secondary resources of these elements. In this work, selective removal of vanadium from tungstate solutions via microbubble floating-extraction was systematically investigated. The results indicated that vanadium can be more easily mineralized over tungsten from tungstate solutions using methyl trioctyl ammonium chloride as mineralization reagent under weak alkaline conditions. Owing to the higher bubble and interface mass transfer rates, high-efficiency enrichment and deep separation of vanadium could be achieved easily. Additionally, the deep recovery of tungsten and vanadium from the floated organic phase could be easily realized using a mixed solution of sodium hydroxide and sodium chloride as stripping agents. The separation mechanism mainly included the formation of hydrophobic complexes, their attachment on the surface of rising bubbles, and their mass transfer at the oil–water interface. Under the optimal conditions, the removal efficiency of vanadium reached 98.5% with tungsten loss below 8% after two-stage microbubble floating-extraction. Therefore, the microbubble floating-extraction could be an efficient approach for separating selectively vanadium from tungstate solutions, exhibiting outstanding advantages of high separation efficiency and low consumption of organic solvents.

关键词： tungsten     vanadium     selective separation     reagent mineralization     microbubble floating-extraction    

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Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

《环境科学与工程前沿（英文）》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1466-7

摘要：

• The α-diversities of resistome were lower in manure and compost than in soils.

关键词： Antibiotic resistance genes     Resistome     Bacterial taxonomy     Transmission chain    

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Mechanistic insights into the selective photocatalytic degradation of dyes over TiO/ZSM-11

《环境科学与工程前沿（英文）》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1701-5

摘要：

● TiO2/ZSM-11 was prepared by a facile solid state dispersion method.

关键词： Selective dye degradation     Photocatalysis     TiO2     ZSM-11     Chemisorption    

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标题 作者 时间 类型 操作

用于超快电子器件的全通型波导

Desong Wang, Ke Wu

期刊论文

Choosing configurations of transmission line tower grounding by back flashover probability value

Dmitry KUKLIN

期刊论文

Reliability analysis of urban gas transmission and distribution system based on FMEA and correlation

Su LI,Weiguo ZHOU

期刊论文

基于ANSYS的汽车变速器检测试验台架有限元分析

刘鹏浩,付胜,朱晓民

期刊论文

基于三线耦合结构的具有灵活带宽的紧凑型平衡式输入无反射带通滤波器

朱雅慧1,2,蔡璟1,2,秦伟1,2,杨汶汶1,2,陈建新1,2

期刊论文

川气东送建设工程综述

曹耀峰

期刊论文

Acoustic fault signal extraction via the line-defect phononic crystals

期刊论文

Calculations of narrow-band transimissities and the Planck mean absorption coefficients of real gases using line-by-line

Huaqiang CHU, Mingyan GU, Huaichun ZHOU, Fengshan LIU

期刊论文

Recent advances in selective acetylene hydrogenation using palladium containing catalysts

Alan J. McCue, James A. Anderson

期刊论文

Preparation of polysulfone-based block copolymer ultrafiltration membranes by selective swelling and

期刊论文

Recent transmission of Mycobacterium tuberculosis in China: the implication of molecular epidemiology

null

期刊论文

Pareto lexicographic α-robust approach and its application in robust multi objective assembly line balancing

null

期刊论文

Highly efficient and selective removal of vanadium from tungstate solutions by microbubble floating-extraction

期刊论文

Antibiotic resistome mostly relates to bacterial taxonomy along a suburban transmission chain

期刊论文

Mechanistic insights into the selective photocatalytic degradation of dyes over TiO/ZSM-11

期刊论文