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Co-based MoF derived metal catalysts: from nano-level to atom-level

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Tungsten 2023年第2期5卷 201-216页

作者： Yuan-Xin Du Yan-Ting zhou Man-zhou zhu College of Materials Science and Engineering and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials Department of Chemistry and Center for Atomic Engineering of Advanced MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of the Ministry of EducationAnhui UniversityHefei 230601China

Co-based metal-organic framework(MOF),a kind of porous crystal material composed of Co ions and organic linkers,is a common type of *** not only has the intrinsic properties of MOF,such as structural diversity,functional adjustability,and high surface area,but more importantly,it contains Co metal species,which are considered by many reports to be active catalytic centers for many ***,metal catalysts always received wide and sustained *** combi-nation of the two types of catalysts can enhance the catalytic performance and achieve the"1+1>2"*** this review,we mainly overview the synthesis methods of Co-based MOF-derived metal catalysts from nano-to atom-level and their applications in the catalysis field in recent years and put forward our own views and prospects for this research direction.

关键词： Metal-organic framework Cobalt Catalysis Nanoparticle Nanocluster Single-atom catalyst

A Variational ODE and its Application to an Elliptic Problem

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Acta Mathematicae Applicatae Sinica 2007年第4期23卷 685-696页

作者： Huan-song zhou Hong-bo zhu Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences P.O. Box 71010 Wuhan 430071 China

In this paper, we consider the following ODE problem { （-u＂（τ）＋（N-1）（N-3）/4τ^2 ）u（τ）＋λu（τ）=f（τ,τ（1-N）/2 u）u（τ）,τ〉0, u∈H, N≥3. （P）,where f ∈ C（（0,＋∞） ×R,R）, f（τ,s） goes t... 详细信息

In this paper, we consider the following ODE problem { （-u＂（τ）＋（N-1）（N-3）/4τ^2 ）u（τ）＋λu（τ）=f（τ,τ（1-N）/2 u）u（τ）,τ〉0, u∈H, N≥3. （P）,where f ∈ C（（0,＋∞） ×R,R）, f（τ,s） goes to p（τ） and q（τ） uniformly in τ 〉 0 as s→ 0 and s→＋∞ respectively, 0≤ p（τ） ≤ q（τ） ∈L^∞（0,∞）. Moreover, for τ 〉 0, f（τ, s） is nondecreasing in s≥ 0. Some existence and non-existence of positive solutions to problem （P） are proved without assuming that p（τ） = 0 and q（τ） has a limit at infinity. Based on these results, we get the existence of positive solutions for an elliptic problem.

关键词： Elliptic equation asymptotically linear mountain pass theorem

An improved adaptive sampling and experiment design method for aerodynamic optimization

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Chinese Journal of Aeronautics 2015年第5期28卷 1391-1399页

作者： Huang Jiangtao Gao Zhenghong zhou zhu Zhao Ke Computational Aerodynamics Institute China Aerodynamics Research and Development Center National Key Laboratory of Aerodynamic Design and Research Northwestern Polytechnical University

Experiment design method is a key to construct a highly reliable surrogate model for numerical optimization in large-scale project. Within the method, the experimental design criterion directly affects the accuracy of the surrogate model and the optimization efficient. According to the shortcomings of the traditional experimental design, an improved adaptive sampling method is proposed in this paper. The surrogate model is firstly constructed by basic sparse samples. Then the supplementary sampling position is detected according to the specified criteria, which introduces the energy function and curvature sampling criteria based on radial basis function （RBF） network. Sampling detection criteria considers both the uniformity of sample distribution and the description of hypersurface curvature so as to significantly improve the prediction accuracy of the surrogate model with much less samples. For the surrogate model constructed with sparse samples, the sample uniformity is an important factor to the interpolation accuracy in the initial stage of adaptive sam- pling and surrogate model training. Along with the improvement of uniformity, the curvature description of objective function surface gradually becomes more important. In consideration of these issues, crowdness enhance function and root mean square error （RMSE） feedback function are introduced in C criterion expression. Thus, a new sampling method called RMSE and crowd- ness enhance （RCE） adaptive sampling is established. The validity of RCE adaptive sampling method is studied through typical test function firstly and then the airfoil/wing aerodynamic opti- mization design problem, which has high-dimensional design space. The results show that RCE adaptive sampling method not only reduces the requirement for the number of samples, but also effectively improves the prediction accuracy of the surrogate model, which has a broad prospects for applications.

关键词： Aerodynamic optimization Crowdness enhance function RBF model RCE adaptive sampfing RMSE feedback

Settlement Mode Analysis for An Immersed Tube Tunnel Considering A Nonuniform Foundation Under Tidal Load

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China Ocean Engineering 2022年第3期36卷 427-438页

作者： WANG Yan-ning zhou Huan-zhu WANG Le-chen Department of Civil and Environmental Engineering Shantou UniversityShantou 515063China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221000China

Immersed tube tunnels are usually placed on soft soil layers in cross-sea tunnelling *** to the influence of stratum conditions and slope design,the longitudinal distribution of substratum layers is generally ***,the inhomogeneous deformation of the element-joint becomes the key factor in the failure of the immersed tube ***,a corresponding calculation method for joint deformation is needed to explore the deformation law of immersed tube *** constructing a three-section immersed tube tunnel analysis model(TTM),the relationship between the two types of deformation of the immersed tube tunnel structure in a longitudinal nonuniform soft soil foundation is described,and the deformation characteristics of the immersed structure under different boundaries are *** on the mechanical behaviour of the joint and foundation,according to the Timoshenko beam on the Vlasov two-parameter foundation(VTM),considering the tidal cyclic load during the operation and maintenance period,an example analysis is ***,the deformation characteristics and development trend of the immersed tube tunnel under the influence of different soil layers are *** obtained results have a certain guiding significance for the deformation calculation of immersed tube tunnels.

关键词： geotechnical engineering immersed tube tunnel theoretical analysis soft soil foundation element-soil interaction

Segmentation algorithm of complex ore images based on templates transformation and reconstruction

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 385-389页

作者： Guo-ying Zhang Guan-zhou Liu Hong zhu School of Mechanical-Electrical and Information China University of Mining ＆ Technology Beijing 100083 China

Lots of noises and heterogeneous objects with various sizes coexist in a complex image,such as an ore image;the classical image thresholding method cannot effectively distinguish between *** segment ore objects with various sizes simultaneously,two adaptive windows in the image were chosen for each pixel;the gray value of windows was calculated by Otsu＇s threshold *** extract the object skeleton,the definition principle of distance transformation templates was *** ores linked together in a binary image were separated by distance transformation and gray *** seed region of each object was picked up from the local maximum gray region of the reconstruction *** from these seed regions,the watershed method was used to segment ore object *** proposed algorithm marks and segments most objects from complex images precisely.

关键词： ores image analysis image segmentation morphological transformation algorithms

Construction of three stereocenters via hydrogenative desymmetrization of 2,2,5-trisubstituted cyclohexane-1,3-diones

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Science China Chemistry 2021年第2期64卷 232-237页

作者： Yi-Xuan Ding zhou-Hao zhu Han Wang Chang-Bin Yu Yong-Gui zhou State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A Ru-catalyzed hydrogenative desymmetrization of 2,2,5-trisubstituted cyclohexane-1,3-diones was developed for construction of three stereocenters including two coherent and discontiguous chiral centers and a chiral quaternary carbon with excellent enantio-and *** synthesis of four stereoisomers could be conducted with high *** desymmetrization could be achieved at gram scale without loss of reactivity and optical purity,and a formal synthesis of bioactive molecule(-)-isocelorbicol was completed.

关键词： desymmetrization hydrogenation 1,3-cyclohexanediones three stereocenters chiral quaternary carbon

Multiple regression models for energy consumption of office buildings in different climates in China

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Frontiers in Energy 2013年第1期7卷 103-110页

作者： Siyu zhou Neng zhu School of Environmental Science and Engineering Tianjin UniversityTianjin 300072 China

The energy consumption of office buildings in China has been growing significantly in recent years. Obviously, there are significant relationships between building envelope and the energy consumption of office buildings. The 8 key building envelope influencing factors were found in this paper to evaluate their effects on the energy consumption of the air-conditioning system. The typical combinations of the key influencing factors were performed in Trnsy simulation. Then on the basis of the simulated results, the multiple regression models were developed respectively for the four climates of China--hot summer and warm winter, hot summer and cold winter, cold, and severely cold. According to the analysis of regression coefficients, the appropriate building envelope design schemes were discussed in different climates. At last, the regression model evaluations consisting of the simulation evaluations and the actual case evaluations were performed to verify the feasibility and accuracy of the regression models. The error rates are within i5% in the simulation evaluations and within ＋ 15% in the actual case evaluations. It is believed that the regression models developed in this paper can be used to estimate the energy consumption of office buildings in different climates when various building envelope designs are considered.

关键词： regression model energy consumption building envelope office building different climates

Cubic metric improvement of aggregated carriers for downlink transmission in LTE-advanced

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 60-63,90页

作者： ZHANG Shao-xin zhou Jun zhu Hong-bo zhu Qi Jiangsu Key Laboratory of Wireless Communications College of Telecommunication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China

To meet long term evolution-advanced （LTE-A） requirements of wider bandwidth and maintain backwards compatibility with LTE release 8 （Rel-8） simultaneously, carrier aggregation has been agreed by the third generation partnership project （3GPP）. High cubic metric （CM） values and peak-to-average power ratio （PAPR） of aggregated component carriers （CCs） exists as an unpleasant issue for both uplink and downlink （DL） transmission. For DL transmission, to use distinct cell ID per DL CC to generate DL reference signal （RS） sequence can mitigate this problem but will cause some other issues on the corresponding uplink carrier. This article proposes two approaches to solve the problem of high CM/PAPR by introducing new variables to change the cell-specific DL RS sequence. In both methods, same cell identifier （cell ID） is allocated to all DL CCs. Simulation results show the performance improvements and prove the effectivity of our proposed approaches.

关键词： LTE-A CC CM/PAPR DL RS ccll ID CC ID total numbcr of aggregatcd CCs

Preference of Chaotic Synchronization in a Coupled Laser System

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Communications in Theoretical Physics 2005年第6X期44卷 1076-1080页

作者： zhou Yun zhu Shi-Qun WU Liang School of Physical Science and Technology Suzhou University Suzhou 215006 China

In a coupled laser system, the dynamics of the receiving laser is investigated when two separate transmitting lasers are injected into the receiving laser with different coupling strengths. It is shown that the phenomenon of preference of chaotic synchronization appears under appropriate coupling conditions. The receiving laser will entrain the pulses of either one or both transmitting lasers when the coupling is strong while it keeps its own dynamics when the coupling is weak.

关键词： coupled laser system dynamics preference of chaotic synchronization