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Laser Polarization Effect on Molecular Harmonic and Elliptically Polarized Attosecond Pulse Generation

Communications in Theoretical Physics 2017年第1期67卷 97-110页

作者：冯立强李文亮刘航 College of Science Liaoning University of Technology State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Key Laboratory at Universities of Education Department of Xinjiang Uygur Autonomous Region for New energy Materials Xinjiang Institute of Engineering School of chemical and Environmental Engineering Liaoning University of Technology

Molecular harmonic spectra of H+2driven by the linearly polarized laser pulses with different polarized angles have been theoretically investigated through solving the two-dimensional time-dependent Schr¨odinger equation.(i) Below-threshold harmonic spectra show a visible enhanced peak around the 7th harmonic(H7), which produces a red-shift phenomenon as the internuclear distance increased. Theoretical analyses show the red-shift enhanced peak is caused by the laser-induced electron transfer between the ground state and the 1st excited state of H+2.(ii) Due to the two-centre interference phenomenon, the above-threshold harmonic spectra exhibit many maxima and minima.(iii)With the introduction of the polarized angle, the anomalous elliptically polarized harmonics can be found. But, with the introduction of the spatial inhomogeneous effect, not only the ellipticities of the harmonics are equal to a stable value of ε～ 0.1–0.3, but also the harmonic cutoffs are extended. As a result, four super-bandwidths of 407 e V, 310 e V,389 e V, and 581 e V can be obtained. Time profiles of the harmonic generations have been shown to explain the harmonic characteristics. Finally, a series of elliptically polarized(ε～ 0.1–0.3) attosecond X-ray pulses with durations from 18 as to 25 as can be directly produced through Fourier transformation of the spectral continuum.

关键词： high-order harmonic generation elliptically polarized attosecond pulse inhomogeneous field resonant enhanced peak two-centre interference

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Optimal design of extractive dividing-wall column using an efficient equation-oriented approach

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Frontiers of chemical Science and Engineering 2021年第1期15卷 72-89页

作者： Yingjie Ma Nan Zhang Jie Li Cuiwen Cao Centre for process Integration Department of Chemical Engineering and Analytical ScienceSchool of EngineeringThe University of ManchesterManchester M139PLUK Key Laboratory of Advanced Control and Optimization for chemical processes(Ministry of Education) East China University of Science and TechnologyShanghai 200237China

The extractive dividing-wall column(EDWC)is one of the most efficient technologies for separation of azeotropic or close boiling-point mixtures,but its design is fairly *** this paper we extend the hybrid feasible path optimisation algorithm(Ma Y,McLaughlan M,Zhang N,Li ***&chemical Engineering,2020,143:107058)for such optimal *** tolerances-relaxation integration method is refined to allow for long enough integration time that can ensure the solution of the pseudo-transient continuation simulation close to the steady state before the required tolerance is *** ensure the gradient and Jacobian information available for optimisation,we allow a relaxed tolerance for the simulation in the sensitivity analysis mode when the simulation diverges under small *** addition,valid lower bounds on purity of the recycled entrainer and the vapour flow rate in column sections are imposed to improve computational *** computational results demonstrate that the extended hybrid algorithm can achieve better design of the EDWC compared to those in *** energy consumption can be reduced by more than 20%compared with existing literature *** addition,the optimal design of the heat pump assisted EDWC is achieved using the improved hybrid algorithm for the first time.

关键词： design extractive dividing-wall column equation-oriented optimisation pseudo-transient continuation model hybrid algorithm

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Efficient Solvent-free Synthesis of Chloropropene Carbonate from the Coupling Reaction of CO_2 and Epichlorohydrin Catalyzed by Magnesium Porphyrins as Chlorophyll-like Catalysts

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Chinese Journal of chemical Engineering 2011年第3期19卷 446-451页

作者：王梅佘远斌周贤太纪红兵 institute of Green Chemistry&Fine chemicals Beijing University of Technology School of Chemistry and chemical Engineering/Key Laboratory of Low-carbon Chemistry&energy Conservation of Guangdong Province Sun Yat-sen University

Highly efficient solvent-free coupling reaction of carbon dioxide(CO2)and epichlorohydrin catalyzed by meso-tetraphenyl porphyrin magnesium(MgTPP)in the presence of triethylamine as co-catalysts is *** a chlorophyll-like catalyst,MgTPP showed excellent activity for the coupling reaction of CO2 and epichlorohydrin to chloropropene carbonate,in which the turnover number could reach up to ***,different factors including the amount of catalyst,reaction temperature,pressure and time were systematically investigated and the optimal reaction conditions were obtained(epichlorohydrin 50 mmol,MgTPP 5.0×10- 3mmol,triethylamine 6.25×10-3 mmol,140°C,1.5 MPa,8 h).A plausible two-pathway mechanism for the coupling reaction of CO 2and epichlorohydrin is proposed to propound the catalysis of MgTPP.

关键词： magnesium prophyrin chlorophyll-like epichlorohydrin carbon dioxide

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Tailoring particle shape for enhancing the homogeneity of powder mixtures:Experimental study and DEM modelling

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Particuology 2021年第1期19卷 58-68页

作者： Maryam Asachi Mohammadreza Alizadeh Behjani Ehsan Nourafkan Ali Hassanpour School of chemical and process Engineering University of LeedsLeeds LS29JTUK School of Maths and Physics University of LincolnBrayford PoolLincolnLN67TSUK

The effect of particle shape modification on the segregation reduction of enzyme granules in laundry detergent powder mixtures was investigated,both experimentally and computationally using Deseret Element Method(DEM).The shape of modified enzyme particles was in such a way that the large and dense enzyme particles were layered by other fine particles in the detergent powder,by means of a process known in the literature as“seeded granulation”.It is found that the homogeneity of modified enzyme particles could be improved significantly comparing to the original spherical enzyme particles in powder ***,the results of this research demonstrated that the segregation-induced properties of the dense/spherical enzyme particles could be lowered by altering their shape,which could enable the enzyme particles to behave almost similar to other ingredients during the pile formation process.

关键词： Segregation minimisation Particle shape modification Seeded granulation Near-infrared spectroscopy Laundry detergent powders Discrete Element Method

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BLE beacon-based floor detection for mobile robots in a multi-floor automation laboratory

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Transportation Safety and Environment 2024年第2期6卷 114-121页

作者： Haiping Wu Hui Liu Thomas Roddelkopf Kerstin Thurow institute of Artificial Intelligence&Robotics(IAIR) Key Laboratory of Traffic Safety on Track of Ministry of EducationSchool of Traffic and Transportation EngineeringCentral South UniversityChangshaHunan 410075China Center of Life Science Automation(celisca) 18119 Rostoc kGerman y institute of Automation(IAT) University Rostock18119 RostockGermany

As an important task of multi-floor localization,floor detection has elicited great *** infrastructures like Wi-Fi and Bluetooth Low energy(BLE)play important roles in floor ***,most floor detection research tends to focus on data modelling but pays little attention to the data collection system,which is the basis of wireless infrastructure-based floor *** fact,the floor detection task can be greatly simplified with proper data collection system *** this paper,a floor detection solution is developed in a multi-floor life science automation lab.A data collection system consisting of BLE beacons,a receiver node and an Internet of Things(IoT)cloud is *** features of the BLE beacon under different settings are evaluated in detail.A mean filter is designed to deal with the fluctuation of the received signal strength indicator data.A simple floor detection method without a training process was implemented and evaluated in more than 100 floor detection *** time delay and floor detection accuracy under different settings are ***,floor detection is evaluated on the H20 multi-floor transportation *** sensor nodes are installed on the robot at different *** floor detection performance with different installation heights is *** experimental results indicate that the proposed floor detection method provides floor detection accuracy of 0.9877 to 1 with a time delay of 5s.

关键词： BLE beacon floor detection multi-floor automation transportation robot

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Gas-liquid-liquid extraction in a novel rotating microchannel extractor

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Chinese Journal of chemical Engineering 2020年第10期28卷 2523-2532页

作者： Rui Ma Chunxin Fan Yubin Wang Jianhong Luo Jun Li Sridhar Komarneni Department of chemical Engineering Sichuan UniversityChengdu 610065China Department of Ecosystem Science and Management and Materials Research institute 204 Energy and the Environment LaboratoryThe Pennsylvania State UniversityUniversity ParkPA 16802USA

In this work,a novel rotating microchannel extractor(RME)is designed and further used for the extraction of chromium(Ⅲ)from ***,the micro-extraction had the same effect as carrying out 2.9-stage cross-flow *** factors,including the gas intake methods,gas intake quantity(Qg),distance between inner rotor and outer wall(D),rotational inner rotor speed(R)and volumetric flow rate(Qa,Qo),were selected to investigate their effect on the extraction efficiency(η)*** relation map ofηwith Weaand We(o-g)for RME provides a comprehension for the gas–liquid–liquid extraction process in this RME system.

关键词： Microextraction Gas–liquid–liquid Rotating microchannel extractor Mass transfer Extraction efficiency

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Numerical investigations on effects of bluff body in flat plate micro thermo photovoltaic combustor with sudden expansion

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Journal of Central South University 2016年第4期23卷 975-982页

作者：鄂加强黄海蛟赵晓欢 College of Mechanical and Vehicle Engineering Hunan University institute of New energy and energy-saving & Emission-reduction Technology Hunan University

In order to reveal combustion characteristics of H_2/air mixture in a micro-combustor with and without bluff body, the effects of inlet velocities, equivalence ratios and bluff body's blockage ratios on the temperature field, pressure of the combustor wall, combustion efficiency and blow-off limit were investigated. The numerical results indicate that the sudden expansion plate micro combustor with bluff body could enhance the turbulent disturbance of the mixed gas in the combustion chamber and the combustion condition is improved. Moreover, a low-speed and high temperature recirculation region was formed between the sudden expansion step and the bluff body so that the high and uniform wall temperature(>1000 K) could be gotten. As a result, it could strengthen the mixing process, prolong the residence time of gas, control the flame position effectively and widen the operation range by the synergistic effect of the bluff body and steps. When the blockage ratio ranged from 0.3 to 0.6, it could be found that the bluff body could play a stabilizing effect and expand combustion blow burning limit, and combustion efficiency firstly was increased with the inlet velocity and equivalence ratio, and then was decreased.

关键词： micro combustor bluff body sudden expansion numerical investigations

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Novel HBD-Containing Zn (dobdc) (datz) as efficiently heterogeneous catalyst for CO_(2) chemical conversion under mild conditions

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Green energy & Environment 2021年第1期6卷 66-74页

作者： Jianwen Lan Ye Qu Ping Xu Jianmin Sun State Key Laboratory of Urban Water Resource and Environment MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and StorageSchool of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin150080China

A novel Zn-based metal–organic framework Zn(dobdc)(datz)[Zn_(2)(H2dobdc)(datz)2$1.5DMF]with plentiful hydrogen bond donors(HBD)groups was facilely synthesized from mixed *** dual activation of metal Zn sites and HBD groups for epoxides by forming Zn–O adduct and hydrogen bonds facilitated the ring-opening of epoxide substrate,which is critical for the subsequent CO_(2) ***,the existence of micropores and N-rich units in Zn(dobdc)(datz)afforded affinity towards CO_(2),which is beneficial to further improvement on catalytic CO_(2) conversion ***,Zn(dobdc)(datz)/Bu4NBr system was proved efficient heterogeneous catalyst for the CO_(2) cycloaddition with epoxides,and 98%propylene carbonate yield was obtained under mild conditions(80C,1.5 MPa and solvent-free).In addition,Zn(dobdc)(datz)/Bu4NBr exhibited remarkable versatility to different epoxides and could be completely recycled over six runs with high catalytic *** highly stable,easily recycle and solvent-free Zn-based MOF reported here displays eco-friendly and efficient performance to CO_(2)conversion.

关键词： Heterogeneous Zn-MOF catalyst HBD groups CO_(2)conversion High versatility and recyclability Mild conditions

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Advances in catalytic conversion of lignocellulose to chemicals and liquid fuels

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Journal of energy Chemistry 2019年第9期28卷 74-86页

作者： Jiping Ma Song Shi Xiuquan Jia Fei Xia Hong Ma Jin Gao Jie Xu State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023 Liaoning China University of the Chinese Academy of Sciences Beijing 100049 China

In response to the awareness of limited fossil resources and environmental concerns,catalytic conversion of renewable lignocellulose biomass to value-added chemicals and fuels is of great significance and attractive for sustainable *** of Biomass Conversion and Bio-energy attached to Dalian National Laboratory for Clean energy has devoted themselves to valorization of lignocellulose biomass since launched in *** research interests focus on breeding of biomass resources(inulin and microalgae),exploration of catalytic and biological technologies,and production of energy chemicals and *** lignocellulose biomass is renewable and abundant,the way of utilization should be reasonable according to its structural characteristics in view of efficiency and *** this review,to celebrate the DICP's 70 th anniversary,we will highlight the major fundamental advances in DICP about the conversion of lignocellulose to value-added chemicals and liquid *** attention will be paid to the transformation of cellulose and its derivatives to glycols,acids and nitrogen-containing chemicals,hemicellulose-derived platform molecule furfural to jet fuels and lignin to aromatics using catalytic technologies.

关键词： Catalysis Lignocellulose Gycols Furan derivatives Aromatics

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Lepton number violation in D meson decay

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Chinese Physics C 2015年第1期39卷 7-14页

作者：董海荣冯峰李海波 institute of High energy Physics Chinese Academy of Sciences Center for High energy Physics Peking University

The lepton number violation （LNV） process can be induced by introducing a fourth generation heavy Majorana neutrino, which is coupled to the charged leptons of the Standard Model （SM）. There have been many previous studies on the leptonic number violating decay processes with this mechanism. We follow the trend to study the process： D→Kllπ with the same-sign dilepton final states. We restrict ourselves to certain neutrino mass regions, in which the heavy neutrino could be on-shell and the dominant contribution to the branching fraction comes from the resonance enhanced effect. Applying the narrow width approximation （NWA）, we found that the upper limit for the branching fractions for D^0 → K^- 1＋1＋π- are generally at the order of 10-12 to 10-9, if we take the most stringent upper limit bound currently available in the literature for the mixing matrix elements. We also provide the constraints, which is competitive compared to the LNV B decays, on the mixing matrix element ｜VeN ｜^2 based on the upper limit of D^0→K^-e＋e＋π- estimated from the Monte-Carlo （MC） study at BESⅢ. Although the constraints are worse than the ones from （0vββ） decay in the literature, the future experiment at the charm factory may yield more stringent constraints.

关键词： Majorana neutrino D meson decay lepton number violating mixing matrix element

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