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Characterization of polycyclic aromatic hydrocarbon emissions from diesel engine retrofitted with selective catalytic reduction and continuously regenerating trap

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Journal of Environmental Sciences 2012年第8期24卷 1449-1456页

作者： Asad Naeem Shah Yunshan ge Jianwei Tan Zhihua Liu chao He Tao Zeng National Lab of Auto Performance and Emission Test School of Mechanical and Vehicular EngineeringBeijing Institute of TechnologyBeijing 100081China Department of Mechanical Engineering University of Engineering and TechnologyLahore 54000Pakistan

Two after treatment units, selective catalytic reduction （SCR） and continuously regenerating trap （CRT）, were independently retrofitted to a diesel engine, with the objective to investigate their impact on the conversion/reduction （CR） of polycyclic aromatic hydrocarbons （PAHs）. The experiments were conducted under the European steady state cycle （ESC） first without any retrofits to get baseline emissions, and then with SCR and CRT respectively, on the same engine. The particulate matter （PM）-phase PAHs were trapped in fiberglass filters, whereas gas-phase PAHs were collected in cartridges, and then analyzed using a gas chromatograph-mass spectrometer （GC-MS）. Both PM-phase and gas-phase PAHs were greatly reduced with CRT showing respective CR of 90.7% and above 80%, whereas only gas-phase PAHs were abated in the case of SCR, with CR of above 75%. Lower molecular weight （LMW） PAHs were in abundance, while naphthalene exhibited a maximum relative contribution （RC） to LMW-PAHs for all three cases. Further, the CR of naphthalene and anthracene were increased with increasing catalyst temperature of SCR, most likely due to their conversion to solid particles. Moreover, the Benzo[a]Pyrene equivalent （BaPeq） of PAHs was greatly reduced with CRT, owing to substantial reduction of total PAHs.

关键词： diesel engine continuously regenerating trap urea-selective catalytic reduction polycyclic aromatic hydrocarbons unregulated emissions

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A real-time calibration method based on time-to-digital converter for accelerator timing system

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Nuclear Science and Techniques 2024年第9期35卷 127-140页

作者： Qi-Hao Duan Liang ge Yan-Hao Jia jie-Yu Zhu Wei Zhang Institute of modern physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The high-intensity heavy-ion accelerator facility(HIAF)is a scientific research facility complex composed of multiple cas-cade accelerators of different types,which pose a scheduling problem for devices distributed over a certain range of 2 km,involving over a hundred *** white rabbit,a technology-enhancing Gigabit Ethernet,has shown the capability of scheduling distributed timing devices but still faces the challenge of obtaining real-time synchronization calibration param-eters with high *** study presents a calibration system based on a time-to-digital converter implemented on an ARM-based System-on-Chip(SoC).The system consists of four multi-sample delay lines,a bubble-proof encoder,an edge controller for managing data from different channels,and a highly effective calibration module that benefits from the SoC *** performance was evaluated with an average RMS precision of 5.51 ps by measuring the time intervals from 0 to 24,000 ps with 120,000 data for every *** design presented in this study refines the calibration precision of the HIAF timing *** eliminates the errors caused by manual calibration without efficiency loss and provides data support for fault *** can also be easily tailored or ported to other devices for specific applications and provides more space for developing timing systems for particle accelerators,such as white rabbits on HIAF.

关键词： HIAF White rabbit Calibration system Time-to-digital converter(TDC)

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Doping-Induced Structure Phase Transition of Layered Ferroelectrics Sr_(2+x)Bi_(4-x)Ti_(5-x)Nb_(x)O_(18)

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Chinese Physics Letters 1999年第7期16卷 523-525页

作者： HAN jie ZOU Guang-tian ge Zhong-jiu National Laboratory of Superhard Materials Jilin UniversityChangchun 130023 Changchun Institute of Physics Chinese Academy of SciencesChangchun 130021

Raman spectra of layered ferroelectrics Sr_(2+x)Bi_(4-x)Ti_(5-x)Nb_(x)O_(18)(0≤x≤2)and Sr_(2)Bi_(4-x)La_(x)Ti_(5)O_(18)at room temperature in the range of 20-1000 cm^(-1)were *** modes were assigned with the interna.1 mode *** doping-induced structure phase transitions were observed at about x=0.5 and 1.25 for Sr_(2+x)Bi_(4-x)Ti_(5-x)Nb_(x)O_(18),separately.

关键词： Transition

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Formation and impact-induced separation of tandem EFPs

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Defence Technology（防务技术） 2020年第3期16卷 668-677页

作者： Hong-bing Ma Yuan-feng Zheng Hai-fu Wang chao ge Cheng-hai Su State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The formation and separation behaviors of tandem EFPs are studied by the combination of experiments and *** results show that different formation and separation processes can be obtained by adjusting the double-layer liners,and simulations agree with experiments ***,the interaction process between the two liners is discussed in details,and the formation and separation mechanism are *** can be found that there are four phases in the formation and separation processes,including impact phase,propulsion phase,slide phase and free flight *** the impact phase,the velocities of two liners rise in turns with kinetic energy *** the propulsion phase,the axial impact becomes insignificant,but the radial interaction between two liners influences the appearance of tandem ***,it should be mentioned that the inner surface of foregoing EFP remains to be in contact with the outer surface of following EFP in the propulsion phase,and the following one would continue to push the foregoing one for about 10μ to 20 μs,causing the velocities of following and foregoing EFPs gradually decreasing and increasing *** the slide phase,an obvious relative movement occurs between the two EFPs,and there would be barely kinetic energy ***,the two EFPs separate gradually and get into the phase of free ***,if the outer and inner liners have the same thickness,the outer copper-inner copper liners form two long EFPs,the outer copper-inner steel liners become a foregoing short steel EFP and a following long copper EFP,and the outer steel-inner copper liners produce a foregoing long copper EFP and a following conical steel *** addition,thickness match also has an important impact on formation appearance and separation process for both outer copperinner copper liners and outer steel-inner copper *** the thickness ratio of outer liner to inner liner decreasing,the length and length-diameter ratio of both foreg

关键词： Shaped charge Liner Tandem EFPs Formation Separation

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Formation behaviors of rod-like reactive shaped charge penetrator and their effects on damage capability

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Defence Technology（防务技术） 2024年第2期32卷 242-253页

作者： Tao Sun Haifu Wang Shipeng Wang chao ge Die Hu Pengwan Chen Yuanfeng Zheng Beijing Institute of Technology State Key Laboratory of Explosion Science and TechnologyBeijing100081China Xi'an Institute of Electromechanical Information Technology Xi'an710065China

Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical *** pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are *** types of sphericalsegment aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with Cu contents of 0%,46.6%,and 66%are fabricated and *** experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect,but the tail skirts disappear over ***,rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP *** simulation analysis,the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning,forming a leading reactive penetrator and a following chemical energy *** unique formation structure determines the damage modes of the aluminum plate and the steel *** analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu *** increasing Cu content,the velocity,activation extent,and reaction extent of Al-PTFE-Cu RRSCP decrease,which contribute to elongation and alleviate the negative effects of chemical reactions on elongation,significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate ***,the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate.

关键词： Reactive materials Al-PTFE composites Reactive liner X-ray Penetration

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The Pd-catalyzed synthesis of difluoroethyl and difluorovinyl compounds with a chlorodifluoroethyl iodonium salt(CDFI)

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Chinese Chemical Letters 2022年第3期33卷 1541-1544页

作者： Yaru Niu Chengyao Kimmy Cao Chenxin ge Hongmei Qu chao Chen Key Laboratory of Systems Bioengineering Ministry of EducationDepartment of Pharmaceutical EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education MOE)Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

Herein, we report a simple and efficient method for the direct installation of chlorodifluoroethyl group onto aromatic molecules of various aromatic amides with a new 2-chloro,2,2-difluoroethyl(mesityl)iodonium salt(CDFI). Moreover, the chlorodifluoroethyl compounds could be smoothly converted into difluorovinyl compounds in a one-pot or discrete procedure and regarded as a steady source of difluorovinyl compounds with “HCl-mask”.

关键词： Iodonium salts C-H activation Pd-catalyzed Difluoroethylation Difluorovinylation

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Enhanced damage mechanism of reinforced concrete targets impacted by reactive PELE: An analytical model and experimental validation

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Defence Technology（防务技术） 2024年第12期42卷 12-30页

作者： Jiahao Zhang Mengmeng Guo Sheng Zhou chao ge Pengwan Chen Qingbo Yu China State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of TechnologyBeijing100081China

Compared with PELE with inert fillings such as polyethylene and nylon,reactive PELE(RPELE)shows excellent damage effects when impacting concrete targets due to the filling deflagration *** present work,an analytical model describing the jacket deformation and concrete target damage impacted by RPELE was presented,in which the radial rarefaction and filling deflagration reaction were *** impact tests of RPELE on concrete target in the 592-1012 m/s were carried out to verify the analytical *** on the analytical model,the angle-length evolution mechanism of the jacket bending-curling deformation was revealed,and the concrete target damage was further *** can find out that the average prediction errors of the front crater,opening and back crater are 6.8%,8.5%and 7.1%,***,the effects of radial rarefaction and deflagration were *** was found that the neglect of radial rarefaction overestimates the jacket deformation and concrete target damage,while the deflagration reaction of filling increases the diameter of the front crater,opening and back crater by 25.4%,24.3%and 31.1%,*** research provides a valuable reference for understanding and predicting the jacket deformation and concrete target damage impacted by RPELE.

关键词： Reactive PELE Concrete target Jacket deformation Radial rarefaction Enhanced damage mechanism

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Experimental investigation on enhanced damage to fuel tanks by reactive projectiles impact

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Defence Technology（防务技术） 2021年第2期17卷 599-608页

作者： Hai-fu Wang Jian-wen Xie chao ge Huan-guo Guo Yuan-feng Zheng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

Enhanced damage to the full-filled fuel tank,impacted by the cold pressed and sintered PTFE/Al/W reactive material projectile(RMP)with a density of 7.8 g/cm3,is investigated experimentally and *** fuel tank is a rectangular structure,welded by six pieces of 2024 aluminum plate with a thickness of 6 mm,and filled with RP-3 aviation *** results show that the kerosene is ignited by the RMP impact at a velocity above 1062 m/s,and a novel interior ignition phenomenon which is closely related to the rupture effect of the fuel tank is ***,the traditional steel projectile with the same mass and dimension requires a velocity up to 1649 m/s to ignite the *** on the experimental results,the radial pressure field is considered to be the main reason for the shear failure of *** mechanism considerations,the chemical energy released by the RMP enhances the hydrodynamic ram(HRAM)effect and provides additional ignition sources inside the fuel tank,thereby enhancing both rupture and ignition ***,to further understand the enhanced ignition effect of RMP,the reactive debris temperature inside the kerosene is analyzed *** initiated reactive debris with high temperature provides effective interior ignition sources to ignite the kerosene,resulting in the enhanced ignition of the kerosene.

关键词： Reactive material projectile Fuel tank Enhanced damage effect Enhanced ignition mechanism Impact behavior

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Undulatory gait planning method of multi-legged robot with passive-spine

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Biomimetic Intelligence & Robotics 2022年第1期2卷 1-8页

作者： Yongchen Tang Guoteng Zhang Dingxin ge chao Ren Shugen Ma School of Itelligence and Information Engineering Tangshan University Tangshan 063000China Schoo of Control Science and Engineering Shandong University Jinan 250061China Tangshan Shinh Ieligent Techuology Co.Itd Tangshan 063000China School of Electrical and Information Engineering Tianjin University Tianjin 300072China Departnent of Robotics Ritsumeikan University Shiga 5258577Japan

In this paper,we propose a new gait planning method for a multi-legged robot which has only 1 degree-of-freedom in each leg and has a passive body joint between two body *** firstly introduce the Finite State Machine(FSM)to the undulatory gait planning method of the 2n-legged ***,the undulatory gait sequence for straight line motion is achieved by undulations *** idea that legged locomotion is achievable by less actuation of 2n-legged robot as well as the gait planning methods are verified finally by simulations and experiments.

关键词： Multi-legged robot Undulatory gait FSM Gait planning Passive-spine

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Exploring on the elderly health management model in tropic area

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Asian Pacific Journal of Tropical Medicine 2017年第6期10卷 684-688页

作者： Yan Song jie-ge Jiao Ze-Jun Chen Hainan Medical University HaikouHainan 570011China Hainan Vocational College of Science and Technology HaikouHainan 571126China The First Affiliated Hospital of Hainan Medical University HaikouHainan 570201China

In this article, based on the characteristics of tropical area, we analyze the beneficial and the disadvantage of tropical area to human health, points out the existing problems in elderly health management pattern in the tropics area, accordingly we discuss how to establish tropical characterized elderly health management, and put forward constructive suggestions.

关键词： Tropical regions Old aee Health management mode

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