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A linear quadratic regulator control of a stand-alone PEM fuel cell power plant

Amar BENAISSA, Boualaga RABHI, Ammar MOUSSI, Dahmani AISSA

《能源前沿(英文)》 2014年 第8卷 第1期   页码 62-72 doi: 10.1007/s11708-013-0291-5

摘要: This paper introduces a technique based on linear quadratic regulator (LQR) to control the output voltage at the load point versus load variation from a stand-alone proton exchange membrane (PEM) fuel cell power plant (FCPP) for a group housing use. The controller modifies the optimal gains by minimizing a cost function, and the phase angle of the AC output voltage to control the active and reactive power output from an FCPP to match the terminal load. The control actions are based on feedback signals from the terminal load, output voltage and fuel cell feedback current. The topology chosen for the simulation consists of a 45 kW proton exchange membrane fuel cell (PEMFC), boost type DC/DC converter, a three-phase DC/AC inverter followed by an LC filter. Simulation results show that the proposed control strategy operated at low commutation frequency (2 kHz) offers good performances versus load variations with low total harmonic distortions (THD) , which is very useful for high power applications.

关键词: modeling of proton exchange membrane fuel cell (PEMFC)     controlling of PEMFC     linear quadratic regulator (LQR)     DC/DC converter     DC/AC inverter    

Monte Carlo simulation of the PEMFC catalyst layer

WANG Hongxing, CAO Pengzhen, WANG Yuxin

《化学科学与工程前沿(英文)》 2007年 第1卷 第2期   页码 146-150 doi: 10.1007/s11705-007-0027-3

摘要: The performance of the polymer electrolyte membrane fuel cell (PEMFC) is greatly controlled by the structure of the catalyst layer. Low catalyst utilization is still a significant obstacle to the commercialization of the PEMFC. In order to get a fundamental understanding of the electrode structure and to find the limiting factor in the low catalyst utilization, it is necessary to develop the mechanical model on the effect of catalyst layer structure on the catalyst utilization and the performance of the PEMFC. In this work, the structure of the catalyst layer is studied based on the lattice model with the Monte Carlo simulation. The model can predict the effects of some catalyst layer components, such as Pt/C catalyst, electrolyte and gas pores, on the utilization of the catalyst and the cell performance. The simulation result shows that the aggregation of conduction grains can greatly affect the degree of catalyst utilization. The better the dispersion of the conduction grains, the larger the total effective area of the catalyst is. To achieve higher utilization, catalyst layer components must be distributed by means of engineered design, which can prevent aggregation.

关键词: catalyst utilization     PEMFC     commercialization     Pt/C catalyst     conduction    

Modeling nanostructured catalyst layer in PEMFC and catalyst utilization

Jiejing ZHANG, Pengzhen CAO, Li XU, Yuxin WANG

《化学科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 297-302 doi: 10.1007/s11705-011-1201-1

摘要: A lattice model of the nanoscaled catalyst layer structure in proton exchange membrane fuel cells (PEMFC) was established by Monte Carlo method. The model takes into account all the four components in a typical PEMFC catalyst layer: platinum (Pt), carbon, ionomer and pore. The elemental voxels in the lattice were set fine enough so that each average sized Pt particulate in Pt/C catalyst can be represented. Catalyst utilization in the modeled catalyst layer was calculated by counting up the number of facets of Pt voxels where “three phase contact” are met. The effects of some factors, including porosity, ionomer content, Pt/C particle size and Pt weight percentage in the Pt/C catalyst, on catalyst utilization were investigated and discussed.

关键词: catalyst layer     PEM fuel cell     lattice model     Monte Carlo method     catalyst utilization    

Structure controlling and process scale-up in the fabrication of nanomaterials

Chunzhong LI,

《化学科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 18-25 doi: 10.1007/s11705-009-0305-3

摘要: Nanotechnology is already having a significant commercial impact, and will very certainly have a much greater impact in the future. The research on process engineering and scale-up will be very important for the commercial production and application of nanomaterials, because the properties and structure of nanomaterials are not only determined by the nucleation and growth process, but also strongly affected by the engineering properties, such as the mixing, the heat and mass transfer, and also the distribution of temperature, concentration, etc. This paper will present some research work in our laboratory on the fabrication of nanomaterials. Based on the chemical engineering principle and methods, many kinds of novel nanomaterials can be synthesized and their structure can be easily controlled through adjusting the parameters of the fluid mixing, and the distribution of temperature, residence time and concentration, etc. By using the micro-mixing, heat and mass transfer and reaction control methods, the host-guest nanocomposites have been assembled and assumed as the novel electroanalytical sensing nanobiocomposite materials. Based on the principles of chemical engineering, the manufacturing technologies for magnetic powders, calcium carbonate, and titanium dioxide have been developed for commercial-scale production, and the largest production scale has reached 15 kt/year.

关键词: scale-up     significant commercial     electroanalytical     engineering     laboratory    

Four kinds of capping materials for controlling phosphorus and nitrogen release from contaminated sediment

《环境科学与工程前沿(英文)》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1463-x

摘要:

• Lanthanum modified bentonite (LMB) can effectively absorb phosphorus (P).

关键词: Sediment     Eutrophication     Thin-layer capping     Phosphorus     Nitrogen     Aluminum-based P-inactivation agent    

Spray characteristics and controlling mechanism of fuel containing CO

Zhen HUANG, Jin XIAO, Xinqi QIAO, Gaozhi JIANG, Yiming SHAO, Seiichi SHIGA, Yasuhiro DAISHO

《能源前沿(英文)》 2012年 第6卷 第1期   页码 80-88 doi: 10.1007/s11708-012-0180-3

摘要: This paper presents studies of spray characteristics and controlling mechanism of fuel containing CO . Using diesel fuel containing CO gas, experiments were conducted on diesel hole-type nozzles and simple nozzles. The steady spray and transient spray characteristics were observed and measured by instantaneous shadowgraphy, high-speed photography, phase Doppler anemometry (PDA) and LDSA respectively. The effects of CO concentration in the fuel, the injection pressure, the nozzle ratio, surrounding gas pressure and temperature on the atomization behavior and spray pattern were evaluated. The results show that the injection of fuel containing CO can greatly improve the atomization and produce a parabolic-shaped spray; and the CO gas concentration, surrounding gas pressure, temperature and nozzle configuration have dominant influences on spray characteristics of the fuel containing CO . New insight into the controlling mechanism of atomization of the fuel containing CO was provided.

关键词: spray characteristics     fuel atomization     fuel containing CO2    

Factors controlling

Chengkun WANG, Xiaojian ZHANG, Chao CHEN, Jun WANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 151-157 doi: 10.1007/s11783-013-0482-7

摘要: The formation of cancinogenic nitrosamines, esp. -nitrosodimethylamine (NDMA) in water and wastewater treatment plants has drawn much attention in recent years. Dissolved organic matter from the transported Luan River water as water source of Tianjin was fractionated with different XAD resins and a series of ultra-filtration membranes with molecular weight (MW) cut-offs of 5k Da, 3k Da, and 1k Da, respectively. The NDMA yields from the raw water and each fraction were measured to investigate their role in NDMA yield. Results indicated that the hydrophilic fraction had a higher NDMA yield than those of hydrophobic fraction and transphilic fraction. The fraction with MW below 1k Da had a higher NDMA yield than that with larger MW. NDMA formation increased as the dissolved organic carbon (DOC) to dissolved organic nitrogen (DON) ratio decreased, which indicated that DON might serve as the real important precursor for NDMA. The correlation between NDMA yield and specific ultraviolet absorbance at 254 nm (SUVA ) suggested that the latter might not represent the specific precursors for NDMA in the water. Besides the water quality, the influences of pH, disinfectant dosage, and disinfection contact time on the formation of NDMA were also examined. These results will help water treatment plants establish measures to control this harmful disinfection by-product.

关键词: N-nitrosodimethylamine (NDMA)     disinfection by-product     dissolved organic nitrogen (DOC)     hydrophilic     molecular weight (MW)     specific ultraviolet absorbance at 254 nm (SUVA254)    

Shape/size controlling syntheses, properties and applications of two-dimensional noble metal nanocrystals

Baozhen An,Mingjie Li,Jialin Wang,Chaoxu Li

《化学科学与工程前沿(英文)》 2016年 第10卷 第3期   页码 360-382 doi: 10.1007/s11705-016-1576-0

摘要: Two dimensional (2D) nanocrystals of noble metals (e.g., Au, Ag, Pt) often have unique structural and environmental properties which make them useful for applications in electronics, optics, sensors and biomedicines. In recent years, there has been a focus on discovering the fundamental mechanisms which govern the synthesis of the diverse geometries of these 2D metal nanocrystals (e.g., shapes, thickness, and lateral sizes). This has resulted in being able to better control the properties of these 2D structures for specific applications. In this review, a brief historical survey of the intrinsic anisotropic properties and quantum size effects of 2D noble metal nanocrystals is given and then a summary of synthetic approaches to control their shapes and sizes is presented. The unique properties and fascinating applications of these nanocrystals are also discussed.

关键词: two-dimension     noble metal     nanocrystal     surface plasmon     controllable synthesis    

大屯矿区深部软岩巷道非对称变形机理及控制对策研究

傅清国,邹朝阳

《中国工程科学》 2011年 第13卷 第11期   页码 102-106

摘要:

通过对孔庄矿工程地质情况调查与分析,结合室内岩石力学实验,运用三维数值模拟方法,研究巷道非对称变形时周围岩体的位移场分布规律,分析巷道推进到上部工作面下方时的应力分布规律。理论研究结果表明,孔庄矿-785 m水平轨道大巷非对称变形主要受其上部采空区煤柱的集中压力控制,黏土矿物遇水膨胀、岩层结构及高地应力作用进一步恶化了巷道围岩结构。该研究可为孔庄矿深部巷道非对称变形控制对策提供初步的理论依据。

关键词: 深部     软岩巷道     非对称变形     控制对策    

Digitalization optical open loop test system for fiber optic gyroscope

ZHANG Deng-wei, SHU Xiao-wu, MU Xu-dong, LIU Cheng

《机械工程前沿(英文)》 2006年 第1卷 第4期   页码 434-438 doi: 10.1007/s11465-006-0053-8

摘要: In order to receive and process the open loop signal from fiber optic gyroscopes speedily, stably and expediently, and to realize the amity interface between human and machine, a digital system that can convert GPIB (general purpose interface bus ) parallel bus into Universal Serial Bus is developed. All the interface functions of GPIB and the hardware system are realized through FPGA. With a digital sampling and processing system designed with VC++ in Windows platform, the real-time controlling procedure, high-speed receiving and sending data can be carried out, and the results can be displayed too. So the design of the system is flexible, the reliability and the stability are improved, error rate is no more than 10, the highest bit rate is 8 MB/s and the open loop detection system for optic fiber gyros achieves standardization and complete digitalization simultaneously.

关键词: stability     real-time controlling     standardization     controlling procedure     complete digitalization    

市场智能经济控制中的统一集方法初探

包极峰,刘扬,贺仲雄

《中国工程科学》 2005年 第7卷 第5期   页码 84-89

摘要:

将统一集与物元变换结合用于市场智能经济控制,建立了统一集智能控制模型,在此模型中把企业的始末状态抽象为可拓学中的物元,应用统一集、界壳论、模糊控制以及可拓学的方法将经济体的初始物元进行物元变换,最后得到满意的初始物元。由于统一集包容了Fuzzy set,Vague set,Extension set,SPA,FEEC等学科,将这些学科中的方法融合起来,提出统一集市场智能经济控制的初步设想,并给出几个应用实例。

关键词: 市场经济     大系统与统一集     控制方法探讨     应用实例    

基于一维纳米结构阵列的质子交换膜燃料电池电极设计的研究进展 Review

杜尚峰

《工程(英文)》 2021年 第7卷 第1期   页码 33-49 doi: 10.1016/j.eng.2020.09.014

摘要: 基于一维铂基纳米结构阵列的三维(3D)有序电极的研究进展表明,它们在解决现有铂/碳(Pt/C)纳米颗粒电极在高性能质子交换膜燃料电池(PEMFC)的传质特性和持久性挑战方面具有巨大的潜力。

关键词: 质子交换膜燃料电池(PEMFC    电极     一维(1D)     氧还原反应(ORR)     催化剂     有序化    

非平面电极双稳态电润湿显示器件研究 Regular Papers-Research Articles

Han ZHANG, Xue-lei LIANG

《信息与电子工程前沿(英文)》 2019年 第20卷 第9期   页码 1289-1295 doi: 10.1631/FITEE.1800167

摘要: 双稳态电润湿显示器仅在状态切换时耗能,在状态稳定时无耗能,是一种非常有潜力的低能耗电子纸显示技术。本文设计和实现了通过常规光刻工艺制备一种非平面电极结构的双稳态电润湿器件。该器件不仅具备视频响应速度,而且有潜力实现可控的像素灰阶。与现有平面电极结构双稳态电润湿器件相比,该新型电极结构可实现更低驱动电压和更高对比度。

关键词: 双稳态电润湿;非平面;控制电极;低电压;高对比度    

On-line controlling system for nitrogen and phosphorus removal of municipal wastewater in a sequencing

LI Jun, NI Yongjiong, WEI Su, CHENG Guobiao, OU Changjin, PENG Yongzhen, GU Guowei, LU Jingen

《环境科学与工程前沿(英文)》 2008年 第2卷 第1期   页码 99-102 doi: 10.1007/s11783-008-0017-9

摘要: The objectives of this study were to establish an on-line controlling system for nitrogen and phosphorus removal synchronously of municipal wastewater in a sequencing batch reactor (SBR). The SBR for municipal wastewater treatment was operated in sequences: filling, anaerobic, oxic, anoxic, oxic, settling and discharge. The reactor was equipped with on-line monitoring sensors for dissolved oxygen (DO), oxidation-reduction potential (ORP) and pH. The variation of DO, ORP and pH is relevant to each phase of biological process for nitrogen and phosphorus removal in this SBR. The characteristic points of DO, ORP and pH can be used to judge and control the stages of process that include: phosphate release by the turning points of ORP and pH; nitrification by the ammonia valley of pH and ammonia elbows of DO and ORP; denitrification by the nitrate knee of ORP and nitrate apex of pH; phosphate uptake by the turning point of pH; and residual organic carbon oxidation by the carbon elbows of DO and ORP. The controlling system can operate automatically for nitrogen and phosphorus efficiently removal.

关键词: DO     relevant     biological process     nitrogen     pH    

TiO supported IrO for anode reversal tolerance in proton exchange membrane fuel cell

《能源前沿(英文)》 2022年 第16卷 第5期   页码 852-861 doi: 10.1007/s11708-021-0811-7

摘要: Fuel starvation can occur and cause damage to the cell when proton exchange membrane fuel cells operate under complex working conditions. In this case, carbon corrosion occurs. Oxygen evolution reaction (OER) catalysts can alleviate carbon corrosion by introducing water electrolysis at a lower potential at the anode in fuel shortage. The mixture of hydrogen oxidation reaction (HOR) and unsupported OER catalyst not only reduces the electrolysis efficiency, but also influences the initial performance of the fuel cell. Herein, Ti4O7 supported IrOx is synthesized by utilizing the surfactant-assistant method and serves as reversal tolerant components in the anode. When the cell reverse time is less than 100 min, the cell voltage of the MEA added with IrOx/Ti4O7 has almost no attenuation. Besides, the MEA has a longer reversal time (530 min) than IrOx (75 min), showing an excellent reversal tolerance. The results of electron microscopy spectroscopy show that IrOx particles have a good dispersity on the surface of Ti4O7 and IrOx/Ti4O7 particles are uniformly dispersed on the anode catalytic layer. After the stability test, the Ti4O7 support has little decay, demonstrating a high electrochemical stability. IrOx/Ti4O7 with a high dispersity has a great potential to the application on the reversal tolerance anode of the fuel cell.

关键词: proton exchange membrane fuel cell (PEMFC)     fuel starvation     cell reverse     reversal tolerance anode     oxygen evolution reaction    

标题 作者 时间 类型 操作

A linear quadratic regulator control of a stand-alone PEM fuel cell power plant

Amar BENAISSA, Boualaga RABHI, Ammar MOUSSI, Dahmani AISSA

期刊论文

Monte Carlo simulation of the PEMFC catalyst layer

WANG Hongxing, CAO Pengzhen, WANG Yuxin

期刊论文

Modeling nanostructured catalyst layer in PEMFC and catalyst utilization

Jiejing ZHANG, Pengzhen CAO, Li XU, Yuxin WANG

期刊论文

Structure controlling and process scale-up in the fabrication of nanomaterials

Chunzhong LI,

期刊论文

Four kinds of capping materials for controlling phosphorus and nitrogen release from contaminated sediment

期刊论文

Spray characteristics and controlling mechanism of fuel containing CO

Zhen HUANG, Jin XIAO, Xinqi QIAO, Gaozhi JIANG, Yiming SHAO, Seiichi SHIGA, Yasuhiro DAISHO

期刊论文

Factors controlling

Chengkun WANG, Xiaojian ZHANG, Chao CHEN, Jun WANG

期刊论文

Shape/size controlling syntheses, properties and applications of two-dimensional noble metal nanocrystals

Baozhen An,Mingjie Li,Jialin Wang,Chaoxu Li

期刊论文

大屯矿区深部软岩巷道非对称变形机理及控制对策研究

傅清国,邹朝阳

期刊论文

Digitalization optical open loop test system for fiber optic gyroscope

ZHANG Deng-wei, SHU Xiao-wu, MU Xu-dong, LIU Cheng

期刊论文

市场智能经济控制中的统一集方法初探

包极峰,刘扬,贺仲雄

期刊论文

基于一维纳米结构阵列的质子交换膜燃料电池电极设计的研究进展

杜尚峰

期刊论文

非平面电极双稳态电润湿显示器件研究

Han ZHANG, Xue-lei LIANG

期刊论文

On-line controlling system for nitrogen and phosphorus removal of municipal wastewater in a sequencing

LI Jun, NI Yongjiong, WEI Su, CHENG Guobiao, OU Changjin, PENG Yongzhen, GU Guowei, LU Jingen

期刊论文

TiO supported IrO for anode reversal tolerance in proton exchange membrane fuel cell

期刊论文