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期刊论文 23

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关键词

10kV高压电力电缆 1

GPRS;嵌入式Internet;S3C2410;SIM100-E 1

三端单片开关电源 1

主动注入 1

云降水微物理参数 1

优化调度 1

分布式人工智能云端平台 1

分布式博弈策略;无人机;分布式模型预测控制;基于Levy飞行的鸽群优化算法;非奇异快速终端滑模观测器;避障策略 1

分组化 1

单端量保护 1

堆场 1

多媒体化 1

峰值供热能力 1

快速可调节性 1

房间温度分布 1

新型供暖末端 1

智能机器人 1

暂态量信息 1

正反馈 1

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Cationic organobismuth complex as an effective catalyst for conversion of CO

Xiaowen ZHANG, Weili DAI, Shuangfeng YIN, Shenglian LUO, Chak-Tong AU

《环境科学与工程前沿(英文)》 2009年 第3卷 第1期   页码 32-37 doi: 10.1007/s11783-008-0068-y

摘要: In order to achieve high-efficiency conversion of CO into valuable chemicals, and to exploit new applications of organobismuth compounds, cationic organobismuth complex with 5,6,7,12-tetrahydrodibenz[c,f] azabismocine framework was examined for the first time for the coupling of CO into cyclic carbonates, using terminal epoxides as substrates and tetrabutylammonium halide as co-catalyst in a solvent-free environment under mild conditions. It is shown that the catalyst exhibited high activity and selectivity for the coupling reaction of CO with a wide range of terminal epoxide. The selectivity of propylene carbonates could reach 100%, and the maximum turnover frequency was up to 10740 h at 120°C and 3 MPa CO pressure when tetrabutylammonium iodide was used as co-catalyst. Moreover, the catalyst is environment friendly, resistant to air and water, and can be readily reused and recycled without any loss of activity, demonstrating a potential in industrial application.

关键词: cationic organobismuth complex     terminal epoxide     carbon dioxide     coupling     cyclic carbonate    

Key technological innovations in the construction of the main terminal of Beijing Daxing International

《工程管理前沿(英文)》 2022年 第9卷 第4期   页码 689-694 doi: 10.1007/s42524-022-0223-3

关键词: Beijing Daxing International Airport     main terminal     architectural technology innovation    

Selective epoxidation of linear terminal olefins with metalloporphyrins under mild conditions

Xiaoguang BAI, Yuanbin SHE

《化学科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 310-313 doi: 10.1007/s11705-009-0168-7

摘要: The epoxidation of linear terminal olefins with metalloporphyrins in the presence of dioxygen and isobutyraldehyde under ambient temperature and atmospheric pressure was investigated. The results show that all olefins could be smoothly converted to epoxides with high selectivities (70%-90%). For the metalloporphyrins with different catalytic activities within 1-hexene epoxidation in the order of Fe>Mn>Co, T( -Cl)PPFe(Ⅲ)Cl was most effective, with a 41.7% yield and 80.2% selectivity of 1,2-epoxyhexane. Various amounts of catalyst were investigated, and it was found that with only 10 ppm catalyst the yield of 1,2-epoxyhexane and turnover number (TON) could reach up to 41.9% and 41859, respectively.

关键词: metalloporphyrins     olefins     dioxygen     epoxidation    

Corrigendum to “Research on DC protection strategy in multi-terminal hybrid HVDC System” [Engineering Corrigendum

Yuping Zheng, Jiawei He, Bin Li, Tonghua Wu, Wei Dai, Ye Li

《工程(英文)》 2022年 第10卷 第3期   页码 183-183 doi: 10.1016/j.eng.2022.02.006

Accurate quantification of 3′-terminal 2′-O-methylated small RNAs by utilizing oxidative deep sequencing

《医学前沿(英文)》 2022年 第16卷 第2期   页码 240-250 doi: 10.1007/s11684-021-0909-7

摘要: The continuing discoveries of novel classes of RNA modifications in various organisms have raised the need for improving sensitive, convenient, and reliable methods for quantifying RNA modifications. In particular, a subset of small RNAs, including microRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs), are modified at their 3′-terminal nucleotides via 2′-O-methylation. However, quantifying the levels of these small RNAs is difficult because 2′-O-methylation at the RNA 3′-terminus inhibits the activity of polyadenylate polymerase and T4 RNA ligase. These two enzymes are indispensable for RNA labeling or ligation in conventional miRNA quantification assays. In this study, we profiled 3′-terminal 2′-O-methyl plant miRNAs in the livers of rice-fed mice by oxidative deep sequencing and detected increasing amounts of plant miRNAs with prolonged oxidation treatment. We further compared the efficiency of stem-loop and poly(A)-tailed RT-qPCR in quantifying plant miRNAs in animal tissues and identified stem-loop RT-qPCR as the only suitable approach. Likewise, stem-loop RT-qPCR was superior to poly(A)-tailed RT-qPCR in quantifying 3′-terminal 2′-O-methyl piRNAs in human seminal plasma. In summary, this study established a standard procedure for quantifying the levels of 3′-terminal 2′-O-methyl miRNAs in plants and piRNAs. Accurate measurement of the 3′-terminal 2′-O-methylation of small RNAs has profound implications for understanding their pathophysiologic roles in biological systems.

关键词: small RNAs     2′-O-methylation     sequencing     RT-qPCR    

on the pollution control against wet weather overflow based on on-site coagulation/flocculation in terminal

Zongqun Chen, Wei Jin, Hailong Yin, Mengqi Han, Zuxin Xu

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1400-z

摘要: Abstract • A way for overflow control based on on-site coagulation/flocculation was proposed. • Coagulant and flocculant dose were optimized based on pollutant removal performance. • Settling time of 5 min is enough in a proper transmission distance. • Fast removal of particulate pollutants could be achieved under varied flow. The pollution caused by wet weather overflow in urban drainage systems is a main factor causing blackening an odorization of urban rivers. The conventional overflow treatment based on coagulation/flocculation in terminal drainage systems requires relatively large space and long retention time demand that makes it not applicable in crowded urban drainage systems or under heavy rains. On-site coagulation/flocculation in terminal drainage pipes was proposed in this study which was aimed to transfer the coagulation/flocculation process to the inside of pipes at the terminal drainage system to save space and reduce the retention time of the coagulation/flocculation process. The optimized dose of chemicals was studied first which was 80 mg/L of coagulant and 0.8 mg/L of flocculant. Settling for only 5 min can remove most of the pollutants at 406.5 m of transmission distance. In addition, the relation of wet weather overflow rate and concentration of pollution load on the on-site coagulation/flocculation process was investigated, which indicated that high removal of pollutant was gained at a large range of flow velocity and pollutant concentration. Finally, the study confirmed electric neutralization, bridging, and net capture as the major mechanisms in this process, and further optimization was proposed. The proposed process can reduce much turbidity, chemical oxygen demand, and total phosphorous, but hardly remove soluble ammonia and organics. This work provides scientific guidance to address wet weather overflow in terminal drainage pipes.

关键词: Wet weather overflow     On-site coagulation/flocculation     Fast removal of particulate pollutants    

港口集装箱码头轮胎式龙门吊优化调度研究

魏众,申金升,肖荣娜,张智文,石定寰

《中国工程科学》 2007年 第9卷 第8期   页码 47-51

摘要:

随着贸易全球化的到来,集装箱运输业飞速发展,港口集装箱码头受到越来越多的重视。轮胎式龙门吊体积大,作业效率低,该环节 已经成为码头作业的瓶颈。提出了轮胎式龙门吊优化调度混合整数规划模型,研究了定量作业条件下的龙门吊优化调度问题,通过实际案例分 析为码头管理者提供决策支持。

关键词: 集装箱码头     堆场     轮胎式龙门吊     优化调度    

混合多端直流输电系统保护方法研究 Article

郑玉平, 何佳伟, 李斌, 吴通华, 戴魏, 李晔

《工程(英文)》 2021年 第7卷 第8期   页码 1064-1075 doi: 10.1016/j.eng.2021.05.002

摘要:

近年来,混合多端直流输电系统快速发展。但是,在混合直流系统中应用的电压源换流器(voltage-source converter, VSC)出口不再需要直流滤波器。此外,考虑到其直流故障电流可被换流器自身有效抑制,直流线路两端也不再需要安装限流电抗器。这意味着线路两端边界缺失,导致应用于常规高压直流输电(line commutated converter based high-voltage direct current, LCC-HVDC)系统和柔性直流(VSC-HVDC)电网的单端量保护均无法适用于混合多端直流输电系统。为此,本文提出了一种适用于混合多端直流输电系统的单端量保护新原理,该方法主要基于暂态信息和主动注入思想实现故障辨识。与应用于LCCHVDC和VSC-HVDC系统的单端量保护相比,所提方法无需依赖线路两端的边界元件,因此更加适用于混合多端直流系统。大量的仿真算例充分验证了所提方法的可行性和优越性。

关键词: 混合多端直流输电系统     单端量保护     暂态量信息     主动注入    

现代通信技术的发展趋势

毕厚杰

《中国工程科学》 2000年 第2卷 第8期   页码 31-34

摘要:

文章综合分析了通信网络、通信终端技术的发展趋势,着重指出我国加强通信软件产业化及发展EDA技术,以迎接入关(WTO)。

关键词: 电信网     分组化     多媒体化     移动化     通信终端    

Current molecular biologic techniques for characterizing environmental microbial community

Dawen GAO, Yu TAO

《环境科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 82-97 doi: 10.1007/s11783-011-0306-6

摘要: Microbes are vital to the earth because of their enormous numbers and instinct function maintaining the natural balance. Since the microbiology was applied in environmental science and engineering more than a century ago, researchers desire for more and more information concerning the microbial spatio-temporal variations in almost every fields from contaminated soil to wastewater treatment plant (WWTP). For the past 30 years, molecular biologic techniques explored for environmental microbial community (EMC) have spanned a broad range of approaches to facilitate the researches with the assistance of computer science: faster, more accurate and more sensitive. In this feature article, we outlined several current and emerging molecular biologic techniques applied in detection of EMC, and presented and assessed in detail the application of three promising tools.

关键词: molecular biological technique     microbial community     denaturing gradient gel electrophoresis (DGGE)     terminal restriction fragment length polymorphism (T-RFLP)     environmental applications    

基于平板热管的新型直膨式辐射可调节供暖末端 Article

吴一凡, 孙弘历, 段梦凡, 林波荣, 赵恒昕, 刘兆鸿

《工程(英文)》 2023年 第20卷 第1期   页码 192-207 doi: 10.1016/j.eng.2021.09.019

摘要:

建筑供暖电气化是实现碳中和目标的有效途径。作为一种清洁和可持续的电气化供暖技术,空气源热泵被广泛应用于缺乏集中供暖的地区。然而,现有末端形式存在难以同时实现间歇性和舒适性,且作为主要构件尚未较好地与空气源热泵匹配等问题。因此,本研究提出了一种与空气源热泵结合的新型辐射可调节供暖末端,以实现电气化节能减碳、间歇性和更好的热舒适性。针对辐射供暖末端目前存在三个主要问题,分别是峰值供热量受限、可调节性受限以及难以与空气源热泵结合,本文通过改进末端结构设计(改进A~E)提供了有效解决方案。研究结果表明,新末端能够将峰值供热量提升23.6%,并为使用者提供从10.1%到30.9%的可调辐射比。在此基础上,巧妙地借助平板热管减少了原有直膨式辐射供暖末端的制冷剂管路长度,进而改善了供暖末端的稳定性(利于回油)、间歇性(降低热惯性)和安全性(降低制冷剂泄漏风险)。此外,本文基于新末端提出了一种新的分阶段运行策略,可进一步提升末端的可调节性。本研究可以为电气化供暖助力建筑低碳提供一定参考。

关键词: 新型供暖末端     空气源热泵     结构优化设计     峰值供热能力     快速可调节性     房间温度分布    

Modeling of solids segregation in circulating fluidized bed boilers

Xuan YAO, Tao WANG, Jia ZHAO, Hairui YANG, Hai ZHANG

《能源前沿(英文)》 2011年 第5卷 第1期   页码 115-119 doi: 10.1007/s11708-010-0103-0

摘要: Segregation always occurs in a circulating fluidized bed (CFB) because of the wide distribution of particle size and density of the bed material. Terminal velocity has a significant influence on solids segregation; thus, it is convenient to describe the segregation tendency using single particle terminal velocity . This paper proposes a segregation model in CFB boilers based on the Cell Model. In each cell along the riser, varied-sized particles have different tendencies toward segregation; finer particles are carried out more easily, while coarser ones tend to sink into the cell. It is assumed that the average terminal velocity , corresponding to the mean particle size in the cell, has a segregation index of = 1.0 as the reference point. The segregation index of particles with higher terminal velocity is lower than 1.0, while that for finer particles is larger than 1.0. The empirical formulae of segregation parameters, namely and , are derived by optimizing experimental data in published literature. The test result of ash size distribution in a 220 t/h CFB boiler validates the reasonableness of the model.

关键词: segregation     model     terminal velocity     circulating fluidized bed (CFB)    

电缆测温系统在工厂供配电系统中的应用

阎红

《中国工程科学》 2007年 第9卷 第11期   页码 172-174

摘要:

探讨了在工矿企业中10kV高压电力电缆在线运行温度检测的必要性与实际应用;列举了感温元件 的选型方法以及温度监测系统的组成与运行;介绍了信息处理软件和故障诊断专家系统软件、电力设备底层 信息网、现场总线技术在电力系统中的应用;实现了不停电状态下对高压电缆及电缆接头等各种电缆的故障 在线监测及诊断功能。

关键词: 10kV高压电力电缆     终端头     温度传感器     监测系统    

Obstacle-circumventing adaptive control of a four-wheeled mobile robot subjected to motion uncertainties

《机械工程前沿(英文)》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0753-3

摘要: To achieve the collision-free trajectory tracking of the four-wheeled mobile robot (FMR), existing methods resolve the tracking control and obstacle avoidance separately. Guaranteeing the synergistic robustness and smooth navigation of mobile robots subjected to motion uncertainties in a dynamic environment using this non-cooperative processing method is difficult. To address this challenge, this paper proposes an obstacle-circumventing adaptive control (OCAC) framework. Specifically, a novel anti-disturbance terminal slide mode control with adaptive gains is formulated, incorporating specified control laws for different stages. This formulation guarantees rapid convergence and simultaneous chattering elimination. By introducing sub-target points, a new sub-target dynamic tracking regression obstacle avoidance strategy is presented to transfer the obstacle avoidance problem into a dynamic tracking one, thereby reducing the burden of local path searching while ensuring system stability during obstacle circumvention. Comparative experiments demonstrate that the proposed OCAC method can strengthen the convergence and obstacle avoidance efficiency of the concerned FMR system.

关键词: four-wheeled mobile robot     obstacle-circumventing adaptive control     adaptive anti-disturbance terminal sliding mode control     sub-target dynamic tracking regression obstacle avoidance    

Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Hongyuan WANG, Xiaolu JIANG, Ya HE, Huashi GUAN

《环境科学与工程前沿(英文)》 2009年 第3卷 第2期   页码 194-199 doi: 10.1007/s11783-009-0018-3

摘要: Four typical coastal sites (rocky shore, sandy shore, mud flat shore, and artificial harbor) at the Yellow Sea were chosen to investigate the spatial and seasonal variations in bacterial communities. This was accomplished by using terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR amplified 16S rDNA fragments. Two kinds of tetrameric restriction enzymes, I and I, were used in the experiment to depict the bacterial community diversity in different marine environments. It was found that the community compositions digested by the two enzymes separately were different. However, the results of bacterial community diversity derived from them were similar. The MDA analysis results of T-RFLP profiles coming from I and I both exhibited a significant seasonal community shift for bacteria and a relatively low spatial variation among the four locations. With I as the sample, the pair wise -tests also revealed that variations were minor between each pair of marine environments, with ranging from 0.198 to 0.349. However, the bacterial community structure in the mud flat site depicted a larger difference than each of the other three sites ( ranging from 0.282 to 0.349).

关键词: terminal restriction fragment length polymorphism (T-RFLP)     bacterial community structure     marine microbial diversity     HhaI     MspI    

标题 作者 时间 类型 操作

Cationic organobismuth complex as an effective catalyst for conversion of CO

Xiaowen ZHANG, Weili DAI, Shuangfeng YIN, Shenglian LUO, Chak-Tong AU

期刊论文

Key technological innovations in the construction of the main terminal of Beijing Daxing International

期刊论文

Selective epoxidation of linear terminal olefins with metalloporphyrins under mild conditions

Xiaoguang BAI, Yuanbin SHE

期刊论文

Corrigendum to “Research on DC protection strategy in multi-terminal hybrid HVDC System” [Engineering

Yuping Zheng, Jiawei He, Bin Li, Tonghua Wu, Wei Dai, Ye Li

期刊论文

Accurate quantification of 3′-terminal 2′-O-methylated small RNAs by utilizing oxidative deep sequencing

期刊论文

on the pollution control against wet weather overflow based on on-site coagulation/flocculation in terminal

Zongqun Chen, Wei Jin, Hailong Yin, Mengqi Han, Zuxin Xu

期刊论文

港口集装箱码头轮胎式龙门吊优化调度研究

魏众,申金升,肖荣娜,张智文,石定寰

期刊论文

混合多端直流输电系统保护方法研究

郑玉平, 何佳伟, 李斌, 吴通华, 戴魏, 李晔

期刊论文

现代通信技术的发展趋势

毕厚杰

期刊论文

Current molecular biologic techniques for characterizing environmental microbial community

Dawen GAO, Yu TAO

期刊论文

基于平板热管的新型直膨式辐射可调节供暖末端

吴一凡, 孙弘历, 段梦凡, 林波荣, 赵恒昕, 刘兆鸿

期刊论文

Modeling of solids segregation in circulating fluidized bed boilers

Xuan YAO, Tao WANG, Jia ZHAO, Hairui YANG, Hai ZHANG

期刊论文

电缆测温系统在工厂供配电系统中的应用

阎红

期刊论文

Obstacle-circumventing adaptive control of a four-wheeled mobile robot subjected to motion uncertainties

期刊论文

Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Hongyuan WANG, Xiaolu JIANG, Ya HE, Huashi GUAN

期刊论文