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Supramolecular binding of amines with functional magnesium tetraphenylporphyrin for CO_2 capture

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Chinese Chemical Letters 2013年第3期24卷 249-252页

作者： fei gao jian-Bin Zhang Chun-Ping Li Tian-Rui Huo Xiong-Hui Wei College of Chemical Engineering Inner Mongolia University of Technology Department of Applied Chemistry College of Chemistry & Molecular EngineeringPeking University

In this work, magnesium tetraphenylporphyrin （MgTPP） was used as a new supramolecular amine-fixing agent. Once introduced, C02 easily competes with MgTPP for amines, leading to the release of MgTPP. The processes can be explained by the fact that the association constant （Kassoc） values of MgTPP with amines were in the range of 0.6 （ethanolamine） to 3.9 （ethylenediamine）, which are lower than the Kassoc values of C02 with these amines. MgTPP interacted with aniline, ethanolamine, pyrrolidine, or ethylenediamine to form 1：1 adducts. Ethylenediamine presents a stronger Kassoc value for MgTPP, so it was considered an optimal agent for C02 capture.

关键词： Supramolecular bindingFixationAmineMagnesium tetraphenylporphyrinC02 capture

MAF-41 with intermediate-sized molecular sieving effect for highly selective separation of styrene

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Science China Chemistry 2019年第10期62卷 1265-1266页

作者： fei Wang jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences

Styrene(ST)is one of the most important chemicals in the world because of its widely applications in the syntheses of rubbers or ***,ST is mainly produced through catalytic dehydrogenation of ethylbenzene(EB)and the product always contains large amount unreacted EB and by-products toluene(Tol)and benzene(Bz)[1].Because of the similar boiling points and sizes of these molecules,the separation of these mixtures to reach polymer-grade ST of 99.5%purity is extremely *** that complicated vacuum/extractive distillation process currently used in industry is highly energy-intensive[2],adsorption separation by using porous adsorbents is a promising alternative *** method can realize ultrahigh selectivity via molecular sieving ***,for complicated mixtures,co-adsorption of smaller molecules makes it difficult to achieve high adsorption selectivity[3].

关键词： separation adsorption selectivity

Volcanoes and Climate:Sizing up the Impact of the Recent Hunga Tonga-Hunga Ha'apai Volcanic Eruption from a Historical Perspective

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Advances in Atmospheric Sciences 2022年第12期39卷 1986-1993页

作者： Meng ZUO Tianjun ZHOU Wenmin MAN Xiaolong CHEN jian LIU fei LIU Chaochao gao State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100029China Key Laboratory for Virtual Geographic Environment Ministry of EducationJiangsu Provincial State Key Laboratory Cultivation Base of Geographical Environment EvolutionSchool of Geography ScienceNanjing Normal UniversityNanjing 210023China School of Atmospheric Sciences Sun Yat-Sen University Key Laboratory of Tropical Atmosphere-Ocean System Ministry of Educationand Southern Marine Science and Engineering Guangdong LaboratoryZhuhai 519082China College of Environmental and Resource Science Zhejiang UniversityHangzhou 310058China

An undersea volcano at Hunga Tonga-Hunga Ha'apai(HTHH)near the South Pacific island nation of Tonga,erupted violently on 15 January *** climate impact of the HTHH volcanic eruption is of great concern to the public;here,we intend to size up the impact of the HTHH eruption from a historical *** influence of historical volcanic eruptions on the global climate are firstly reviewed,which are thought to have contributed to decreased surface temperature,increased stratospheric temperature,suppressed global water cycle,weakened monsoon circulation and El Niño-like sea surface *** understanding of the impacts of past volcanic eruptions on global-scale climate provides potential implication to evaluate the impact of the HTHH *** on historical simulations,we estimate that the current HTHH eruption with an intensity of 0.4 Tg SO_(2)injection will decrease the global mean surface temperature by only 0.004℃in the first year after eruption,which is within the amplitude of internal variability at the interannual time scale and thus not strong enough to have significant impacts on the global climate.

关键词： Hunga Tonga-Hunga Ha'apai volcanic eruption global climate surface temperature monsoon ENSO

Accelerated Learning for Restricted Boltzmann Machine with a Novel Momentum Algorithm

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Chinese Journal of Electronics 2018年第3期27卷 483-487页

作者： gao Xiaoguang LI fei WAN Kaifang Northwestern Polytechnical University

We investigated two commonly used momentum algorithms, Classical momentum(CM) and Nesterov momentum(NM). We found that, when used in Restricted Boltzmann machine(RBM), they have two main problems: The first one is their performances are not obvious and not as good as expected. The second one is they may lose accelerating ability in the later stage of training process. Aiming at these two problems, we proposed the Weight momentum algorithm and evaluated our approach on four datasets. It has been demonstrated that our methods can achieve better performance under both reconstruction error and classification rate criterions.

关键词： Deep learning Restricted Boltzmann machine(RBM) Momentum algorithm Weight momentum(WM)

Painlevé analysis, auto-Bäcklund transformations, bilinear forms and soliton solutions for a(2+1)-dimensional variable-coefficient modified dispersive water-wave system in fluid mechanics

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Communications in Theoretical Physics 2023年第2期75卷 46-55页

作者： fei-Yan Liu Yi-Tian gao Ministry-of-Education Key Laboratory of Fluid Mechanics and National Laboratory for Computational Fluid Dynamics Beijing University of Aeronautics and AstronauticsBeijing 100191China

In this paper,we investigate a(2+1)-dimensional variable-coefficient modified dispersive waterwave system in fluid *** prove the Painlevéintegrability for that system via the Painlevé*** find some auto-B?cklund transformations for that system via the truncated Painlevé*** forms and N-soliton solutions are constructed,where N is a positive *** discuss the inelastic interactions,elastic interactions and soliton resonances for the two *** also graphically demonstrate that the velocities of the solitons are affected by the variable coefficient of that system.

关键词： fluid mechanics variable-coefficient modified dispersive water-wave system Painlevéanalysis bilinear forms soliton solutions auto-Bäcklund transformations

Lithiated Nafion-garnet ceramic composite electrolyte membrane for solid-state lithium metal battery

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Journal of Energy Chemistry 2020年第7期29卷 237-247,I0008页

作者： Jing gao Qinjun Shao jian Chen Advanced Rechargeable Battery Laboratory Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Single-ion conducting solid polymer electrolytes are expected to play a vital role in the realization of solid-state Li metal *** this work,a lithiated Nafion(Li-Nafion)-garnet ceramic Li6.25La3 Zr2 Al0.25O12(LLZAO)composite solid electrolyte(CSE)membrane with 30μm thickness was prepared for the first *** employing X-ray photoelectron spectroscopy and transmission electron microscope,the interaction between LLZAO and Li-Nafion was *** is found that the LLZAO interacts with the Li-Nafion to form a space charge layer at the interface between LLZAO and *** space charge layer reduces the migration barrier of Li-ions and improves the ionic conductivity of the CSE *** CSE membrane containing 10 wt%LLZAO exhibits the highest ionic conductivity of2.26×10-4 S cm-1 at 30℃among the pristine Li-Nafion membrane,the membrane containing 5 wt%,20 wt%,and 30 wt%LLZAO,*** also exhibits a high Li-ion transference number of 0.92,and a broader electrochemical window of 0-+4.8 V ***+/Li than that of 0-+4.0 V ***+/Li for the pristine Li-Nafion *** is observed that the CSE membrane not only inhibits the growth of Li dendrites but also keeps excellent electrochemical stability with the Li *** from the above merits,the solid-state LiFePO4/Li cell fabricated with the CSE membrane was practically charged and discharged at 30℃.The cell exhibits an initial reversible discharge specific capacity of 160 mAh g-1 with 97%capacity retention after 100 cycles at 0.2 C,and maintains discharge specific capacity of 126 mAh g-1 after500 cycles at 1 *** CSE membrane prepared with Li-Nafion and LLZAO is proved to be a promising solid electrolyte for advanced solid-state Li metal batteries.

关键词： Single-ion conductor Composite solid electrolyte Lithiated Nafion Garnet ceramic Solid-state Li metal battery

Asymptotic inference for AR(1) panel data

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Applied Mathematics(A Journal of Chinese Universities) 2020年第3期35卷 265-280页

作者： SHEN jian-fei PANG Tian-xiao School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China

A general asymptotic theory is given for the panel data AR(1) model with time series independent in different cross sections. The theory covers the cases of stationary process, local to unity process, unit root process, mildly integrated, mildly explosive and explosive processes. It is assumed that the cross-sectional dimension and time-series dimension are respectively N and T. The results in this paper illustrate that whichever the process is, with an appropriate regularization, the least squares estimator of the autoregressive coefficient converges in distribution to a normal distribution with rate at least O(N-1/3). Since the variance is the key to characterize the normal distribution, it is important to discuss the variance of the least squares estimator. We will show that when the autoregressive coefficient ρ satisfies |ρ| 1. ρ = 1 is the critical point where the convergence rate changes radically. The transition process is studied by assuming ρ depending on T and going to 1. An interesting phenomenon discovered in this paper is that, in the explosive case, the least squares estimator of the autoregressive coefficient has a standard normal limiting distribution in the panel data case while it may not has a limiting distribution in the univariate time series case.

关键词： AR(1)model Least squares estimator Limiting distribution Non-stationray Panel data

A Review of Research Progress in the Genesis of Colloform Pyrite and Its Environmental Indications

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1353-1369页

作者： gao Shang HUANG fei WANG Yinghui gao Wenyuan Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines College of Resource and Civil Engineering Northeastern University

Colloform pyrite is a special form of nano-micro polycrystalline aggregation growth, for which a suitable term is ＂aggregates of nano-micro crystals＂. This kind of colloform texture is observed in various geological bodies, such as ancient sedimentary rocks, modern marine and lake sediments, various types of ore deposits, and modern seafloor hydrothermal vents. This paper summarizes the latest developments and research into the definition, formation mechanisms, and environmental indications of colloform pyrite. There appears to be three main formation mechanisms of colloform pyrite： pseudomorphic replacement; biogenic precipitation; and inorganic precipitation. The morphology, particle size, trace element content and preferential growth orientations of coUoform pyrite microcrystals can be important indicators for sedimentary environments, hydrothermal activity, and ore-forming processes. We suggest that the microscopic features of nano-micro crystals in colloform pyrite and their aggregation growth patterns need further investigation. The relationships between formation mechanisms of colioform pyrite, organic activity and depositional environments require further exploration. To reveal the nature of nano-micro grain aggregation growth in colloform pyrite and analyse its growth environment and evolutionary history, it is supposed to apply nanoscientific and nanotechnological methods, further integrate consideration of macroscopic geological backgrounds and microscopic mineral growth phenomena, combine high-resolution imaging systems and in situ quantitative microanalysis methods and constitute a mergence of earth science, thermodynamics and kinetics, life science, material science, and chemistry in the study.

关键词： colloform pyrite nano-micro crystals aggregation growth mechanism environmental indication nanoscience and nanotechnology

A novel strong tracking cubature Kalman filter and its application in maneuvering target tracking

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Chinese Journal of Aeronautics 2019年第11期32卷 2489-2502页

作者： An ZHANG Shuida BAO fei gao Wenhao BI School of Aeronautics Northwestern Poly technical UniversityXi’an 710072China School of Electronics and Information Northwestern Poly technical UniversityXi’an 710129China

The fading factor exerts a significant role in the strong tracking idea. However, traditional fading factor introduction method hinders the accuracy and robustness advantages of current strong-tracking-based nonlinear filtering algorithms such as Cubature Kalman Filter(CKF) since traditional fading factor introduction method only considers the first-order Taylor expansion. To this end, a new fading factor idea is suggested and introduced into the strong tracking CKF *** new fading factor introduction method expanded the number of fading factors from one to two with reselected introduction positions. The relationship between the two fading factors as well as the general calculation method can be derived based on Taylor expansion. Obvious superiority of the newly suggested fading factor introduction method is demonstrated according to different nonlinearity of the measurement function. Equivalent calculation method can also be established while applied to CKF. Theoretical analysis shows that the strong tracking CKF can extract the thirdorder term information from the residual and thus realize second-order accuracy. After optimizing the strong tracking algorithm process, a Fast Strong Tracking CKF(FSTCKF) is finally established. Two simulation examples show that the novel FSTCKF improves the robustness of traditional CKF while minimizing the algorithm time complexity under various conditions.

关键词： Algorithm time complexity Cubature Kalman filter Nonlinear filtering Robustness Strong tracking filter