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多孔纤维素球衍生物的制备与性能

武汉大学学报（自然科学版） 2000年第2期46卷 166-168页

作者：孟令芝杜传青符兆林何永炳陈远荫武汉大学化学与环境科学学院武汉430072

由脱脂棉制备的多孔纤维素球经 SEM对其整体结构和表面孔结构进行了表征 .这种多孔的纤维素球经环氧氯丙烷活化后 ,再分别与两种氨基酸反应 ,制得了两种纤维素球氨基酸衍生物 (PCS- ,PCS- ) ,测定了它们对金属离子及人血清蛋白的吸附... 详细信息

由脱脂棉制备的多孔纤维素球经 SEM对其整体结构和表面孔结构进行了表征 .这种多孔的纤维素球经环氧氯丙烷活化后 ,再分别与两种氨基酸反应 ,制得了两种纤维素球氨基酸衍生物 (PCS- ,PCS- ) ,测定了它们对金属离子及人血清蛋白的吸附能力 .

关键词：多孔纤维素球吸附金属离子人血清蛋白衍生物

Active TLCGD control of plane asymmetric buildings under earthquake excitation

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Acta Mechanica Sinica 2011年第5期27卷 817-822页

作者： chuan fu College of Architecture North China University of Technology 100144 Beijing China

The sealed,tuned liquid column gas damper （TLCGD） with gas-spring effect extends the frequency range of application and efficiently increases the modal structural *** tuned liquid column gas damper （ATLCGD） is developed for the vibration control of plane asymmetric buildings subjected to earthquake excitation,improving the performance of the passive control *** active behaviour is obtained by adjusting the pressure at the end of the liquid column using a pressurised *** classical linear quadratic regulator （LQR） design is presented as a straightforward approach to optimal *** simulations indicate a significant vibration reduction of plane asymmetric buildings by active control within the strong motion of the dynamic response.

关键词： Asymmetric building Earthquake excitation Active control LQR algorithm

BIVARIATE LAGRANGE-TYPE VECTOR VALUED RATIONAL INTERPOLANTS

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Journal of Computational Mathematics 2002年第2期20卷 207-216页

作者： chuan-qing Gu Gong-qing Zhu Department of Mathematics Shanghai UniversityShanghai 200436China Department of Mathematics Hefei Polytechnic UniversityHefei 230009China

Focuses on a study that presented an axiomatic definition to bivariate vector valued rational interpolation on distinct plane interpolation points. Definition; Existence and uniqueness; Connection.

关键词： bivariate vector value rational interpolation determinantal formula

Supramolecular synthesis of coumarin derivatives catalyzed by a coordination-assembled cage in aqueous solution

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Science China Chemistry 2019年第6期62卷 713-718页

作者： Shao-chuan Li Li-Xuan Cai Li-Peng Zhou Fang Guo qing-fu Sun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences College of Chemistry Liaoning University

A self-assembled Pd_4L_2 cage is employed as a water-soluble molecular flask for the synthesis of functionalized coumarins from a series of salicylaldehyde derivatives and cyanoacetates/malononitrile. The catalytic reaction features mild aqueous conditions and broad substrate scope. Crystal structures of the host-guest complexes for two substrates and one analogous intermediate have been obtained, shedding light on the supramolecular reaction mechanism. Michaelis-Menten kinetic studies were performed in one typical case, revealing that the rate of product formation has been enhanced by over 23-fold in contrast to the background reaction without cage. Moreover, the same reaction catalyzed by a smaller Pd_6L_4 cage gives a mixture of products and much lower yields, suggesting that fine-tuning on the size and symmetry of the cages' cavity is crucial for their applications in supramolecular catalysis.

关键词： coordination-assembly cage encapsulation Knoevenagel condensation

Microstructural evolution of a steam-turbine rotor subjected to a water-quenching process: numerical simulation and experimental verification

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Advances in Manufacturing 2019年第1期7卷 84-104页

作者： chuan Wu qing-Ling Meng National-Local Joint Engineering Laboratory of Intelligent Manufacturing Oriented Automobile Die & Mould College of Mechanical Engineering Tianjin University of Technology and Education Tianjin 300222 People's Republic of China College of Civil Engineering Tianjin University Tianjin 300072 People's Republic of China

Cr-Ni-Mo-V steam-turbine rotors have been widely used as key components in power plants. In this study, a coupled thermomechano-metallurgical model was proposed to simulate the phase transformation and transformation-induced plasticity (TRIP) of a 30Cr2Ni4MoV steam-turbine rotor during a water-quenching process, which was solved using a user defined material mechanical behavior (UMAT) subroutine in ABAQUS. The thermal dilation, heat generation from plastic work, transformation latent heat, phase transformation kinetics, and TRIP were considered in the model. The thermomechanical portion of the model was used to predict the evolution of temperature, strain, and residual stress in the rotor. The phase transformation that occurred during the quenching process was considered. Constitutive models of phase transformations (austenite to pearlite, austenite to bainite, and austenite to martensite) and TRIP were developed. Experimental data were adopted and compared with the predicted results to verify the accuracy of the model. This demonstrates that the model is reliable and accurate. Then, the model was utilized to predict the temperature variation, dimensional change, minimum austenitization time, residual stress, TRIP, and volume fractions of each phase. It is concluded that this model can be a useful computational tool in the design of heat-treatment routines of steam-turbine rotors.

关键词： Thermomechano-metallurgical model user defined material mechanical behavior (UMAT) subroutine Microstructural evolution Transformation-induced plasticity (TRIP)- Residual stress

Theoretical Studies on Structural and Spectroscopic Properties of Photoelectrochemical Cell Ruthenium Sensitizers―the Derivatives of N3

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Chemical Research in Chinese Universities 2012年第4期28卷 696-702页

作者： CHEN Jie WANG Jian BAI fu-quan ZHENG qing-chuan ZHANG Hong-xing State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryJilin UniversityChangchun 130021P.R.China

A series of dye molecules was designed ***,azoles and their derivatives were chosen as the modifying groups linking to ancillary ligands of [Ru（dcbpyH2）2（NCS）2]（N3,dcbpy=4,4＇-dicarboxy2,2＇-bipyridine;NCS=thiocyanato）.Density functional theory（DFT） based approaches were applied to exploring the electronic structures and properties of all these *** dye molecule with 1,2,4-triazole groups which exhibits a very high intensity of absorption in visible region,was ***-dependent DFT（TD-DFT） results indicate that the ancillary ligand dominates the molecular orbital（MO） energy levels and masters the absorption transition nature to a certain *** deprotonation of anchoring ligand not only affects the frontier MO energy levels but also controls the energy gaps of the highest occupied MO（HOMO） to the lowest unoccupied MO（LUMO） and LUMO to LUMO＋1 *** the gap between LUMO-LUMO＋1 is small enough,the higher efficiency of dye-sensitized solar cell（DSSC） should be expected.

关键词： Dye-sensitized solar cell Density functional theory(DFT) Frontier molecular orbital Absorption spectrum Deprotonation

Uplink NOMA signal transmission with convolutional neural networks approach

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Journal of Systems Engineering and Electronics 2020年第5期31卷 890-898页

作者： LIN chuan CHANG qing LI Xianxu School of Electronic and Information Engineering Beihang UniversityBeijing 100191China State Grid Information and Telecommunication Branch Beijing 100761China

Non-orthogonal multiple access(NOMA), featuring high spectrum efficiency, massive connectivity and low latency, holds immense potential to be a novel multi-access technique in fifth-generation(5G) communication. Successive interference cancellation(SIC) is proved to be an effective method to detect the NOMA signal by ordering the power of received signals and then decoding them. However, the error accumulation effect referred to as error propagation is an inevitable problem. In this paper,we propose a convolutional neural networks(CNNs) approach to restore the desired signal impaired by the multiple input multiple output(MIMO) channel. Especially in the uplink NOMA scenario,the proposed method can decode multiple users' information in a cluster instantaneously without any traditional communication signal processing steps. Simulation experiments are conducted in the Rayleigh channel and the results demonstrate that the error performance of the proposed learning system outperforms that of the classic SIC detection. Consequently, deep learning has disruptive potential to replace the conventional signal detection method.

关键词： non-orthogonal multiple access(NOMA) deep learning(DL) convolutional neural networks(CNNs) signal detection

Cu-catalyzed cross-couplings under ligandless conditions

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Chinese Chemical Letters 2007年第10期18卷 1199-1202页

作者： chuan Zhou Tao Juan Li Xin Cui Yao fu qing Xiang Guo Department of Chemistry University of Science and Technology of China Hefei 230026 China

The possibility to carry out Cu-catalyzed cross-couplings under ligandless conditions was studied. It was found that by using K3PO4 as the base, the cross-coupling could proceed successfully between aryl iodides and s... 详细信息

关键词： Cu Catalysis Cross-coupling Ligand free

Reconstruction of the Sturm-Liouville operator with discontinuities from a particular set of eigenvalues

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Applied Mathematics(A Journal of Chinese Universities) 2018年第2期33卷 225-233页

作者： XU Xiao-chuan YANG chuan-fu Department of Applied Mathematics School of Science Nanjing University of Science and Technology

Sturm-Liouville operators on a finite interval with discontinuities are considered. We give a uniqueness theorem for determining the potential and the parameters in boundary and under discontinuous conditions from a particular set of eigenvalues, and provide corresponding reconstruction algorithm, which can be applicable to McLaughlin-Rundell＇s uniqueness theorem （see J. Math. Phys. 28, 1987）.

关键词： Sturm-Liouville operator discontinuous condition inverse spectral problem reconstruction al-gorithm