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Chinese Journal of Structural Chemistry 2005年第7期24卷 851-857,740页

作者： WANGZun-Yao HANXiang-yun WANGLian-sheng SchooloftheEnvironment NanjingUniversityJiangsu210093China／／SchoolofChemicalandBiologicalEngineeringYanchengInstituteofTechnologyJiangsu224003China SchooloftheEnvironment NanjingUniversityJiangsu210093China SchoolofChemicalandBiologicalEngineering YanchengInstituteofTechnologyJiangsu224003China

Twenty eight alkyl(1-phenylsulfonyl) cycloalkane carboxylates were computed at the B3LYP/6-31G* level. Based on linear solvation energy theory, two quantitative correlation equations of the molecular structures of alkyl(1-phenylsulfonyl) cycloalkane carboxylate com- pounds to their chromatographic retention (capacity factor lgKW) and the toxicity for photo- bacterium phosphoreum (–lgEC50) were developed by using the molecular structural parameters as theoretical descriptors (r2 = 0.9501, 0.9488). The two quantitative correlation equations were consequently cross validated by leave-one-out (LOO) validation method with q2 of 0.9113 and 0.9281, respectively. The result showed that the two equations achieved in this work by B3LYP/6-31G* are both more advantageous than those from AM1, and can be used to predict the lgKW and –lgEC50 of congeneric organics.

关键词： chromatographic retention acute toxicity photobacterium density functional theory method linear solvation energy theory quantitative structure-property relationship (QSPR) quantitative structure-activity relationships (QSAR)

LARGE EDDY SIMULATION OF PULSATING TURBULENT OPEN CHANNEL FLOW

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Journal of Hydrodynamics 2004年第6期16卷 681-686页

作者： ZOULi-yong LIUNan-sheng LUXi-yun DepartmentofMechanicsandMechanicalEngineering UniversityofScienceandTechnologyofChinaHefei230026China

Pulsating turbulent open channel flow has been investigated by the use ofLarge Eddy Simulation (LES) tech-nique coupled with dynamic Sub-Grid-Scale (SGS) model for turbulentSGS stress to closure the governing equations. Three-dimensional filtered Navier-Stokes equationsare numerically solved by a fractional — step method. The objective of this study is to deal withthe behavior of the pulsating turbulent open channel flow and to examine the reliability of the LESapproach for predicting the pulsating turbulent flow. In this study, the Reynolds number (Re_τ) ischosen as 180 based on the friction velocity and the channel depth. The frequency of the drivingpressure gradient for the pulsating turbulent flow ranges low, medium and high value. Statisticalturbulence quantities as well as the flow structures are analyzed.

关键词： Large Eddy Simulation (LES) turbulent open channel flow pulsating turbulentflow Sub-Grid-Scale (SGS) model

Experimental study on energy characteristics and ignition performance of recessed multichannel plasma igniter

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Chinese Physics B 2020年第6期29卷 339-348页

作者： Bang-huang Cai Hui-Min Song Min Jia yun Wu Wei Cui sheng-Fang huang Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’an 710038China

In the extreme conditions of high altitude,low temperature,low pressure,and high speed,the aircraft engine is prone to flameout and difficult to start secondary ignition,which makes reliable ignition of combustion chamber at high altitude become a worldwide *** solve this problem,a kind of multichannel plasma igniter with round cavity is proposed in this paper,the three-channel and five-channel igniters are compared with the traditional *** discharge energy of the three igniters was compared based on the electric energy test and the thermal energy test,and ignition experiments was conducted in the simulated high-altitude environment of the component combustion *** results show that the recessed multichannel plasma igniter has higher discharge energy than the conventional spark igniter,which can increase the conversion efficiency of electric energy from 26%to 43%,and the conversion efficiency of thermal energy from 25%to 73%.The recessed multichannel plasma igniter can achieve greater spark penetration depth and excitation area,which both increase with the increase of *** the same height,the inlet flow helps to increase the penetration depth of the *** recessed multichannel plasma igniter can widen the lean ignition boundary,and the maximum enrichment percentage of lean ignition boundary can reach 31%.

关键词： high altitude extreme condition recessed multichannel plasma igniter discharge energy lean ignition boundary

Solidification Properties of CaO-SiO_2-TiO_2 Based Mold Fluxes

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Journal of Iron and Steel Research International 2011年第7期18卷 15-19,52页

作者： HE sheng-ping huang Qing-yun ZHANG Guo-xing LU Yong-jian WANG Qian Chongqing Key Laboratory of Metallurgical Engineering College of Materials Science and EngineeringChongqing University Chongqing 400044 China

In continuous casting of peritectic steel grades sensitive to longitudinal cracking, the solidification properties of mold fluxes play an important role in keeping smooth running of continuous casting process and achieving high surface quality of casting strands. To reduce fluorine pollution in molten slag, types of CaO-SiO2-TiO2 （CTS） based mold fluxes were investigated. The solidification and crystallization properties, including viscosity η at 1 573 K, break temperature Tbr, crystallization ratio Rc and solidification mineragraphy were measured, which were compared with those of CaO-SiO2-CaF2 based mold fluxes. The experiments show that there are unstable viscosity-high tem- perature properties and high Tbr in part of CTS slag system, which are bad for lubrication between liquid flux film and strand. And when temperature is below Tbr, the viscosities change slowly during cooling in some part of this slag system, which imply that liquid mold fluxes solidify slowly and it is easy to cause surface longitudinal cracks on strand. Major mineragraphy of the CaO-SiO2-TiO2 based mold fluxes are CaO · TiO2 or CaO · TiO2 and CaO · SiO2 · TiO2. TiN and Ti（C,N） can be formed in mold fluxes bearing high TiO2 during the continuous casting.

关键词： mold flux solidification property peritectic steel mineragraphy

Quantitative analysis on the phase margin of ADRC

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Control Theory and Technology 2023年第1期21卷 4-15页

作者： sheng Zhong Yi huang Beijing Aerospace Automatic Control Institute Beijing100854China Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing100049China

The paper analyzes and compares the phase margins of four active disturbance rejection control(ADRC)designs,which are based on different common-used extended state observers(ESOs)of various orders,for second-order *** quantitative results indicate that,besides good dynamic response,ADRC can guarantee enough phase *** is also proved that by decreasing the order of ESO,the phase margin can be ***,it is demonstrated that the phase margins of the ADRC-based systems can be almost uninfluenced by the uncertainties of the system ***,the theoretical results are verified by both simulations and experiments on a motion control platform.

关键词： Uncertain system Active disturbance rejection control(ADRC) Extended state observer(ESO) Phase margin Crossover frequency

Fabrication and magnetic properties of NiFe-ZnO nano-granular films

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Rare Metals 2013年第3期32卷 269-272页

作者： Xue-yun Zhou Dong-sheng Yao Faculty of Science Jiujiang University Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology Tianjin University

Excellent soft magnetic and high frequency prop- erties were obtained successfully in the （Ni75Fe25）x（ZnO）1-x granular films fabricated on the glass substrate by RF magnetron oblique sputtering. The microstructure, mag- netic and high frequency properties were investigated systematically. High resolution transmission electron micrographs show that the film consists of fcc Ni75Fe25 particles uniformly embedded in an amorphous insulating matrix ZnO with particle size a few nanometers. The （Ni75Fe25）x（ZnO）1-x films exhibit excellent soft magnetic properties in a widex range from 0.50 to 0.80 with coer- civity not exceeding 5 × 10^-4 T, which is ascribed to the exchange coupling between magnetic particles. Especially for the sample with x = 0.64, coercivities in hard and easy axes are 5.0 ×10^-5 and 3.6 × 10^-4 T, respectively, and the electric resistivity ρ reaches 1,790 μΩ.cm. The dependence of complex permeability u = u′- ju″on frequency f shows that the real part u′ is more than 130 below 500 MHz, and the ferromagnetic resonance fre- quency fr reaches 1.32 GHz, implying the promising for high frequency application.

关键词： Soft magnetic property Nano-granular thinfilms High frequency application

Soller slits automatic focusing method for multi-element fluorescence detector

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Nuclear Science and Techniques 2016年第5期27卷 179-187页

作者： Ya-yun Yang Qian Gao Song-Qi Gu Hai-sheng Yu Rui-You Lu Yu-Ying huang Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China University of Chinese Academy of Sciences Beijing 100049 China

In X-ray absorption fine structure(XAFS) experiments,Soller slits are widely used as filter devices in order to improve the signal to noise *** high accuracy manual focusing operations is a time-consuming process;therefore,this work introduces an automatic focusing method for Soller slits in multi-element fluorescence *** method establishes a relation model between the fluorescence intensity distribution and the coordinates of the fluorescence excitation *** to this relation model,the actual coordinates of the fluorescence excitation point can be deduced from the detected fluorescence intensity distribution and used in focusing *** method has proven to be feasible in an XAFS experiment at the BL14W1 beamline of the Shanghai Synchrotron Radiation Facility.

关键词：荧光检测器聚焦方法狭缝 X射线吸收精细结构 XAFS实验关系模型光强度分布高信噪比

A parameter formula connecting PID and ADRC

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Science China(Information Sciences) 2020年第9期63卷 175-187页

作者： sheng ZHONG Yi huang Lei GUO Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper presents a parameter formula connecting the well-known proportional-integralderivative(PID) control and the active disturbance rejection control(ADRC). On the one hand, this formula gives a quantitative lower bound to the bandwidth of the extended state observer(ESO) used in ADRC,implying that the ESO is not necessarily of high gain. On the other hand, enlightened by the design of ADRC, a new PID tuning rule is provided, which can guarantee both strong robustness and nice tracking performance of the closed-loop systems under the PID control. Moreover, it is proved that the ESO can be rewritten as a suitable linear combination of the three terms in PID, which can give a better estimate for the system uncertainty than the single integral term in the PID controller. Theoretical results are verified also by simulations in the paper.

关键词： nonlinear uncertain systems proportional-integral-derivative PID active disturbance rejection control ADRC extended state observer ESO

Mechanisms involved in triggering debris flows,within a cohesive gravel soil mass on a slope:a case in SW China

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Journal of Mountain Science 2017年第4期14卷 611-620页

作者： CHEN Ning-sheng ZHU yun-hua huang Qi IQBAL Javed DENG Ming-feng HE Na Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences and Ministry of Water ResourcesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Southwest Petroleum University Chengdu 610500China Southwest Electric Power Design Institute CO LTDChengdu 610021China Department of Earth Sciences COMSATS Institute of Information Technology22060 AbbottabadPakistan

The triggering mechanisms of debris flows were explored in the field using artificial rainfall experiments in two gullies, Dawazi Gully and Aizi Gully, in yunnan and Sichuan Provinces, China,respectively. The soils at both sites are bare, loose and cohesive gravel-dominated. The results of a direct shear test, rheological test and back-analysis using soil mass stability calculations indicate that the mechanisms responsible for triggering debris flows involved the decreases in static and dynamic resistance of the soil. The triggering processes can be divided into 7 stages: rainfall infiltration, generation of excess runoff, high pore water pressure, surface erosion, soil creep, soil slipping, debris flow triggering and debris flow increment. In addition, two critical steps are evident:(i) During the process of the soil mass changing from a static to a mobile state, its cohesion decreased sharply(e.g., the cohesion of the soil mass in Dawazi Gully decreased from 0.520 to0.090 k Pa, a decrease of 83%). This would have reduced the soil strength and the kinetic energy during slipping, eventually triggered the debris flow.(ii) When the soil mass began to slip, the velocity and the volume increment of the debris flow fluctuated as a result of the interaction of soil resistance and the sliding force. The displaced soil mass from the source area of the slope resulted in the deposition of a volume of soil more than 7-8 times greater than that in the source area.

关键词： Debris flow Cohesive gravel soil Triggering mechanism Slip Soil erosion

Enhancing oxygen reduction reaction of Pt-Co/C nanocatalysts via synergetic effect between Pt and Co prepared by one-pot synthesis

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Rare Metals 2023年第1期42卷 146-154页

作者： yun-Feng Wu Ji-Wei Ma yun-Hui huang School of Materials Science and Engineering Tongji UniversityShanghai201804China School of Materials Science and Engineering Huazhong University of Science and TechnologyWuhan430074China

Designing highly active and durable electrocatalysts towards oxygen reduction reaction(ORR)plays a paramount importance for proton exchange membrane fuel ***-based binary alloys Pt-M(M=3d-transition metals)possessing excellent electronic and geometric properties have received increasing interests as highly active ***,we report a series of Pt_(x)Co/C(x=1,2,3)catalysts by a facile one-pot soft-chemistry *** the acidic conditions,the mass activities of PtCo/C,Pt_(2)Co/C and Pt_(3)Co/C are 0.526,0.462 and 0.441 A·mgPt^(-1),which are 2.60,2.31 and 2.22 times higher than that of Pt/C(0.200 A·mgPt^(-1)),*** specific activities of PtCo/C,Pt_(2)Co/C and Pt_(3)Co/C are 706.59,679.41 and 801.83μA·cm^(-2),which are accordingly 2.89,2.76 and 3.28 times higher than that of Pt/C(244.75μA·cm^(-2)).Notably,Pt_(3)Co/C shows a remarkable *** 5000 cycles of the accelerated durability testing,the mass activity and specific activity of Pt_(3)Co/C catalyst are 2.47 and 3.80 times higher than that of the commercial Pt/C,*** improved ORR activity and durability can be ascribed to the synergistic interaction between Pt and Co.

关键词： Proton exchange membrane fuel cells(PEMFCs) Pt_(x)Co/C catalysts Synergetic effect Oxygen reduction reaction(ORR) One-pot synthesis