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A big step forward to graphene-based atomic hydrogen storage

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Science China Chemistry 2022年第2期65卷 197-198页

作者： sheng-li chen College of Chemistry and Molecular Science Wuhan UniversityWuhan 430072China

Considered as the ultimate solution for the energy and environment crises,hydrogen energy plays a crucial role in the realization of worldwide carbon *** are three key issues for the practical utilization of hydrogen energy:high-capacity storage,safe transportation and reversible release,among which hydrogen storage is the first step.

关键词： hydrogen realization energy

Characterization of Phase Transition in Heisenberg Fluids from Density Functional Theory

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Communications in Theoretical Physics 2009年第2期51卷 287-292页

作者： li liang-sheng li li chen Xiao-Song Institute of Theoretical Physics Chinese Academy of Sciences P.O. Box 2735 Beijing 100190 China

The phase transition of Heisenberg fluid has been investigated with the density functional theory in mean-field approximation （MF）. The matrix of the second derivatives of the grand canonical potential Ω with respect to the particle density fluctuations and the magnetization fluctuations has been investigated and diagonalized. The smallest eigenvalue being 0 signalizes the phase instability and the related eigenvector characterizes this phase transition. We find a Curie line where the order parameter is pure magnetization and a spinodal where the order parameter is a mixture of particle density and magnetization. Along the spinodal, the character of phase instability changes continuously from predominant condensation to predominant ferromagnetic phase transition with the decrease of total density. The spinodal meets the Curie line at the critical endpoint with the reduced density p＊=pσ3=0.224 and the reduced temperature T＊ =kT/ε=1.87 （σ is the diameter of Heisenberg hard sphere and e is the coupling constant）.

关键词： critical phenomena order-disorder magnetic liquid

In Situ Synthesis of Block Copolymer Nano-assemblies by Polymerization- induced Self-assembly under Heterogeneous Condition

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Chinese Journal of Polymer Science 2017年第4期35卷 455-455,456-479页

作者： sheng-li chen Peng-fei Shi 张望清 Key Laboratory of Functional Polymer Materials of the Ministry of Education Institute of Polymer ChemistryNankai University Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Nankai University

Controlled synthesis of amphiphilic block copolymer nanoparticles in a convenient way is an important and interest topic in polymer science. In this review, three formulations of polymerization-induced self-assembly to in situ synthesize block copolymer nanoparticles are briefly introduced, which perform by reversible addition-fragmentation chain transfer （RAFT） polymerization under heterogeneous conditions, e.g., aqueous emulsion RAFT polymerization, dispersion RAFT polymerization and especially the recently proposed seeded RAFT polymerization. The latest developments in several selected areas on the synthesis of block copolymer nano-assemblies are highlighted.

关键词： Block copolymers Self-assembly Emulsion RAFT polymerization Dispersion RAFT polymerization SeededRAFT polymerization

Metathesis of 1-butene and 2-butene to propene over Re_2O_7 supported on macro-mesoporous γ-alumina prepared via a dual template method

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Journal of Natural Gas Chemistry 2012年第2期21卷 105-108页

作者： Lei Sang sheng-li chen Guimei Yuan Min Zheng Ju You Aicheng chen Rui li Lanjing chen State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of PetroleumBeijing 102249China

Macro-mesoporous γ-alumina support（MMA） was prepared by a sol-gel route in aqueous medium using pseudo-boehmite as aluminum source and polystyrene microspheres and Pluronic P123 as hard and soft dual templates,*** had a BET specific surface area of about 259 m2 g-1,total pore volume of about 1.61 cm3 g-1,macropore diameter of about 102 nm,and mesopore diameter of about 14 ***2O7/MMA and conventional Re2O7/Al2O3 were prepared by a incipient-wetness impregnation method,and their catalytic performances in the metathesis of 1-butene and 2-butene were tested in a fixed-bed tubular *** result showed that Re2O7/MMA possessed higher activity and far longer working life-span than conventional Re2O7/Al2O3.

关键词： butene metathesis propene rhenium oxide polystyrene microspheres macro-mesoporous alumina

Preparation of mesoporous alumina with large pore size and their supported rhenium oxide catalysts in metathesis of 1-butene and 2-butene to propene

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Journal of Natural Gas Chemistry 2012年第3期21卷 352-359页

作者： Lei Sang sheng-li chen Guimei Yuan Zheng Zhou Rui li Aicheng chen Min Zheng Ju You State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of PetroleumBeijing 102249China

Mesoporous γ-aluminas with large pore size （up to 19 nm, denoted as MAI9） are prepared from dispersed pseudo-boehmite using pluronic P123 as template. It is found that these mesoporous alumina supported rhenium oxide catalysts were more active and have far longer working life-span in gas-phase metathesis of 1-butene and 2-butene to propene than rhenium oxide on conventional alumina with small pore size （5 nm）. At 60 ℃ and atmospheric pressure with WHSV = 1 h^-1, the similar stable conversions of butene （ca. 55%） for all the 13 wt% Re207/alumina catalysts were obtained near the chemical equilibrium, and the stable working life-spans of Re2OT/MA19 were far longer than that of Re2O7/A1203, being about 70 h and 20 h, respectively.

关键词： mesoporous alumina rhenium oxide metathesis butene propene

Surface dealuminated Beta zeolites supported WO3 catalyst and its catalytic performance in tetralin hydrocracking

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Petroleum Science 2022年第6期19卷 3116-3123页

作者： Yan-Ting Zhang Ni-Ni Zhang sheng-li chen Hui Dang Tao Wu State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of Petroleum-BeijingBeijing 102249China

In this study,selective dealumination of Beta zeolites was performed through partially removing the templating agent in Beta zeolites by calcination and then removing the aluminum on the external surface of Beta zeolites with acid *** catalysts were prepared by loading WO_(3)onto these dealuminated Beta *** was shown that the surface SiO_(2)/Al_(2)O_(3)of selectively dealuminated Beta zeolites was higher than that of conventionally dealuminated samples for the same bulk SiO_(2)/Al_(2)O_(3),and the hydrogenation activity of the catalyst of the selectively dealuminated Beta zeolites was lower than that of conventionally dealuminated Beta *** experimental results for tetralin hydrocracking to BTX showed that the catalysts based on the selectively dealuminated Beta zeolites had higher BTX selectivity and lower coke formation rate than that the catalysts based on the conventionally dealuminated Beta zeolites.

关键词： Beta zeolites Dealumination Calcination Hydrocracking

EXPERIMENTAL STUDY ON A NEW TYPE OF AERATOR IN SPILLWAY WITH LOW FROUDE NUMBER AND MILD SLOPE FLOW

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Journal of Hydrodynamics 2009年第3期21卷 415-422页

作者： SU Pei-lan liAO Hua-sheng QIU Yue li chen-juan State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

Experimental study on aeration characteristics of various aeration devices was conducted in the spillway tunnel of the Pubugou hydropower project, Sichuan Province, China. It is shown by comparison that the new type of aeration device, namely, the aerator with a trapezoidal-shaped slot and a steep-slope section（ATSS）, can avoid water accumulation in the cavity of the aeration device in the project, thus can effectively solve the backwater problems arising from this project and be used for a wide range of different water levels, without any drain facilities. Above the water level of 840 m, the water contained in the cavity can be eliminated completely, which means that the recommended new type of aerator can meet the aeration demands in the spillway of the project with low Froude number and may be of practical significance and of interest to other projects with similar types of aeration devices.

关键词： aeration device a trapezoidal-shaped slot and a steep-slope section(ATSS) air entrainment cavitation

A new via chain design method considering confidence level and estimation precision

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第9期13卷 702-710页

作者： Xiao-hua LUO li-sheng chen Jiao-jiao ZHU Xiao-lang YAN Institute of VLSI Design Zhejiang UniversityHangzhou 310027China

For accurate prediction of via yield, via chains are usually fabricated on test chips to investigate issues about vias. To minimize the randomness of experiments and make the testing results more convincing, the confidence level and estimation precision of the via failure rate are investigated in this paper. Based on the Poisson yield model, the method of determining an adequate number of total vias is obtained using the law of large numbers and the de Moivre-Laplace theorem. Moreover, for a specific confidence level and estimation precision, the method of determining a suitable via chain length is proposed. For area minimization, an optimal combination of total vias and via chain length is further determined. Monte Carlo simulation results show that the method is in good accordance with theoretical analyses. Results of via failure rates measured on test chips also reveal that via chains designed using the proposed method has a better performance. In addition, the proposed methodology can be extended to investigate statistical significance for other failure modes.

关键词： Poisson yield model Via chain Via failure rate Confidence level Estimation precision

Novel high-safety aeroengine performance predictive control method based on adaptive tracking weight

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Chinese Journal of Aeronautics 2024年第7期37卷 352-374页

作者： Qian chen Hanlin sheng Jie ZHANG Jiacheng li College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Increasing attention has been attracted to the dynamic performance and safety of advanced performance predictive control systems of the next-generation *** latest research demonstrates that Subspace-based Improved Model Predictive Control(SIMPC)can overcome the difficulty in solving the predictive model in MPC/NMPC ***,applying constant design parameters cannot maintain consistent control effects in all ***,the designed system relies too much on sensor-measured data,and thus it is difficult to thoroughly validate the safety of the system because of its high *** means that any potential hardware/software faults will endanger the ***,this paper first presents a novel nonlinear mapping relationship to adaptively tune the tracking weight online with the change of Power Lever Angle(PLA)and real-time relative tracking ***,without introducing additional design parameters,an Adaptive Tracking Weight-based SIMPC(ATW-SIMPC)controller is designed to improve the control performance in all operating states ***,a Primary/Backup Hybrid Control(PBHC)strategy with the ATW-SIMPC controller as the primary system and the traditional speed(Nf)controller as the backup system is proposed to ensure *** designed affiliated switching controller and the real-time monitor therein can be used to realize reasonable and smooth switching between primary/backup systems,so as to avoid bump *** PBHC system switches to the Nf controller when the ATW-SIMPC controller is wrong because of potential hardware/software faults;otherwise,the ATW-SIMPC controller keeps acting on the *** main results prove that the ATW-SIMPC controller with the optimal nonlinear mapping relationship,compared with the existing SIMPC controller,uplifts the dynamic control performance by 32%and reduces overshoots to an allowable limit,resulting in a better control effect in full *** comparison results consistently i

关键词： Aeroengine Model predictive control Hybrid system Adaptive weight Safety