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Chinese Chemical Letters 2009年第12期20卷 1393-1396页

作者： Geng xu zhan Zhu Liu Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine (Peking Union Medical College) Ministry of Education Institute of Materia Medica Peking Union Medical College & Chinese Academy of Medical Sciences Beijing 100050 China

Four new chiral 1,2,3,4-tetrahydroisoquinoline-derived G-amino alcohols were synthesized from commercially available LDOPA. These ligands were evaluated in the asymmetric addition of diethylzinc to benzaldehydes and showed different catalytic activities （up to 86% ee）. The solvent played an important role in the enantioselective process. The transition state models were proposed to explain the reversion of the product configuration.

关键词： β-Amino alcohol Tetrahydroisoquinoline Diethylzinc Asymmetric addition

Blockchain Technology Empowers Telecom Network Operation

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China Communications 2022年第1期19卷 274-283页

作者： Huidi Li Peng Gao Yi zhan min Tan China Mobile Group Beijing 100032China China Mobile Group Design Institute Co. Ltd Beijing 100080China

Telecom operators are deploying the fifth generation(5G) networks around the world which promises high information transmission rate, wide network coverage, low communication delay, and easy access to a large number of devices. However, during the construction and operation of 5G, telecom operators face many challenges, such as insufficient frequency resources, low efficiency of network management, information opacity, risks of data interoperability, and network privacy vulnerabilities. As 5G is generally deployed in heterogeneous networks with massive ubiquitous devices, it is quite necessary to provide secure and decentralized solutions. Blockchain is a distributed system maintained by multiple parties with inherit features including decentralization,traceability and tamperproof. These features collectively contribute to a new application ecosystem where transactions are secure and trustworthy. Therefore,blockchain is expected to integrate with 5G networks to build safer and more reliable mobile network infrastructures. This paper firstly discusses the merits of blockchain technology and the benefits of integrating it with 5G networks. Then a variety of applications of blockchain technology in telecom network operation are reviewed, including spectrum sharing, international roaming settlement, network operation management, number selection management and supply chain management. In the end, we show our recently advance in integrating blockchain in 5G by introducing a multi framework based blockchain service network architecture deployed in real environment.

关键词： blockchain 5G IoT smart contracts BSN

Combined effects of topography and bottom friction on shoaling internal solitary waves in the South China Sea

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Applied Mathematics and Mechanics(English Edition) 2019年第4期40卷 421-434页

作者： Dalin TAN Jifu ZHOU xu WANG zhan WANG Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of Sciences School of Engineering Sciences University of Chinese Academy of Sciences

A numerical study to a generalized Korteweg-de Vries (KdV) equation is adopted to model the propagation and disintegration of large-amplitude internal solitary waves (ISWs) in the South China Sea (SCS). Based on theoretical analysis and in situ measurements, the drag coefficient of the Chezy friction is regarded as inversely proportional to the initial amplitude of an ISW, rather than a constant as assumed in the previous studies. Numerical simulations of ISWs propagating from a deep basin to a continental shelf are performed with the generalized KdV model. It is found that the depression waves are disintegrated into several solitons on the continental shelf due to the variable topography. It turns out that the amplitude of the leading ISW reaches a maximum at the shelf break, which is consistent with the field observation in the ***, a dimensionless parameter defining the relative importance of the variable topography and friction is presented.

关键词： internal solitary wave(ISW) South China Sea(SCS) Chezy friction vari-able topography

DISCOVERING NON-TERminATING INPUTS FOR MULTI-PATH POLYNOMIAL PROGRAMS

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Journal of Systems Science & Complexity 2014年第6期27卷 1286-1304页

作者： LIU Jiang xu ming zhan Naijun ZHAO Hengjun Chongqing Key Laboratory of Automated Reasoning and Cognition CIGITChinese Academy of Sciences Department of Computer Science and Technology East China Normal University State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of Sciences

This paper investigates the termination problems of multi-path polynomial programs （MPPs） with equational loop guards. To establish sufficient conditions for termination and nontermination simultaneously, the authors propose the notion of strong/weak non-termination which under/over- approximates non-termination. Based on polynomial ideal theory, the authors show that the set of all strong non-terminating inputs （SNTI） and weak non-terminating inputs （WNTI） both correspond to tile real varieties of certain polynomial ideals. Furthermore, the authors prove that the variety of SNTI is computable, and under some sufficient conditions the variety of WNTI is also computable. Then by checking the computed SNTI and WNTI varieties in parallel, termination properties of a consid- ered MPP can be asserted. As a consequence, the authors establish a new framework for termination analysis of MPPs.

关键词： Polynomial ideals polynomial programs termination analysis.

Initial Development of a Novel Amphibious Robot with Transformable Fin-Leg Composite Propulsion Mechanisms

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Journal of Bionic Engineering 2013年第4期10卷 434-445页

作者： Shiwu zhang xu Liang Lichao xu min xu Department of Precision Machinery and Precision Instrumentation University of Science and Technology of China Hefei 230026 P. R. China

Amphibious robots are very attractive for their broad applications in resource exploration, disaster rescue, and recon- naissance. However, it is very challenging to develop the robots for their complex, amphibious working environments. In the complex amphibious environment, amphibious robots should possess multi-capabilities to walk on rough ground, maneuver underwater, and pass through transitional zones such as sandy and muddy terrain. These capabilities require a high-performance propulsion mechanism for the robots. To tackle a complex task, a novel amphibious robot （AmphiHex-I） with,transformable fin-leg composite propulsion mechanisms is developed. With the fin-leg composite propulsions, AmphiHex-I can walk on rough and soft substrates and swim in water with many maneuvers. This paper presents the structural design of the transformable fin-leg propulsion mechanism and its driving module. A hybrid model is used to explore the dynamics between the trans- formable legs and transitional environment such as granular medium. The locomotion performances of legs with various ellip- tical shapes are analyzed, which is verified by the coincidence between the model predictions and the simulation results. Further, an orthogonal experiment is conducted to study the locomotion performance of a two-legged platform walking with an asyn- chronous gait in the sandy and muddy terrain. Finally, initial experiments of AmphiHex-I walking on various lands and swimming in water are implemented. These results verify that the transformable fin-leg mechanisms enable the amphibious robot to pass through a complex, amphibious working environment.

关键词： amphibious robot transformable fin-leg composite propulsion mechanism amphibious environment

Power Extraction Performance of a Semi-activated Flapping Foil in Gusty Flow

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Journal of Bionic Engineering 2017年第1期14卷 99-110页

作者： Jiapu zhan Bing xu Jie Wu Jing Wu Department of A erodynamics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Jiangsu Key Laboratory of Hi- Tech Research for Wind Turbine Design Nanjing 210016 China

A numerical investigation on the power extraction performance of a semi-activated flapping foil in gusty flow is conducted by using the commercial software FLUENT. The foil is forced to pitch around the axis at one-third chord and heave in the vertical direction due to the period lift force. Different from previous work with uniform flow, an unsteady flow with cosinusoidal velocity profile is considered in this work. At a Reynolds number of 1100, the influences of the mechanical parameters （spring constant and damping coefficient）, the amplitude and frequency of the pitching motion, the amplitude of the gust fluctuation and the phase difference between the pitching motion and the gusty flow on the power extraction performance are systematically investigated. Compared with the case of uniform flow, the capability energy harvesting of the system is enhanced by the introduction of the gusty flow. For a given pitching amplitude and frequency, the power extraction efficiency increases with the gust fluctuation amplitude. Moreover, with an optimal phase difference between pitch and gust （φ = 180°）, the efficiency can be further enhanced due to the generation of high lift force.

关键词： semi-activated flapping foil gusty flow power extraction performance

Multi-type sensor placement and response reconstruction for building structures: Experimental investigations

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Earthquake Engineering and Engineering Vibration 2018年第1期17卷 29-46页

作者： Rong-Pan Hu You-Lin xu Sheng zhan Department of Civil and Environmental Engineering The Hong Kong Polytechnic University

Estimation of lateral displacement and acceleration responses is essential to assess safety and serviceability of high-rise buildings under dynamic loadings including earthquake excitations. However, the measurement information from the limited number of sensors installed in a building structure is often insufficient for the complete structural performance assessment. An integrated multi-type sensor placement and response reconstruction method has thus been proposed by the authors to tackle this problem. To validate the feasibility and effectiveness of the proposed method, an experimental investigation using a cantilever beam with multi-type sensors is performed and reported in this paper. The experimental setup is first introduced. The finite element modelling and model updating of the cantilever beam are then performed. The optimal sensor placement for the best response reconstruction is determined by the proposed method based on the updated FE model of the beam. After the sensors are installed on the physical cantilever beam, a number of experiments are carried out. The responses at key locations are reconstructed and compared with the measured ones. The reconstructed responses achieve a good match with the measured ones, manifesting the feasibility and effectiveness of the proposed method. Besides, the proposed method is also examined for the cases of different excitations and unknown excitation, and the results prove the proposed method to be robust and effective. The superiority of the optimized sensor placement scheme is finally demonstrated through comparison with two other different sensor placement schemes： the accelerometer-only scheme and non-optimal sensor placement scheme. The proposed method can be applied to high-rise buildings for seismic performance assessment.

关键词： experimental investigation multi-type sensors inclinometer response reconstruction optimal sensor placement

Optimizing Photovoltaic Performance by Kinetic Quenching of Layered Heterojunctions

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Chinese Journal of Polymer Science 2022年第1期40卷 29-37页

作者： Li-Feng xu zhan-Wen xu Jia-Ping Lin Li-Quan Wang Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The mixing morphology control plays a crucial role in photovoltaic power generation,yet this specific effect on device performances remains ***,we employed computational approaches to delineate the photovoltaic properties of layered heterojunction polymer solar cells with tunable mixing ***-step quench and two-step quench strategies were proposed to adjust the mixing morphology by thermodynamic and kinetic *** computation for the one-step quench revealed that modulating interfacial widths and interfacial roughness could significantly promote the photovoltaic performance of layered heterojunction polymer solar *** two-step quench can provide a buffer at a lower temperature before the kinetic quenching,leading to the formation of small-length-scale islands connected to the interface and a further increase in photovoltaic *** discoveries are supported by recent experimental evidence and are anticipated to guide the design of photovoltaic materials with optimal performance.

关键词： Dissipative particle dynamics Drift-diffusion model Polymer solar cells Quench

Pretreatment of agricultural residues by supercritical CO_2 at 50–80 °C to enhance enzymatic hydrolysis

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Journal of Energy Chemistry 2019年第4期28卷 39-45页

作者： Meng-jiao Zhao Qin-qin xu Guo-min Li Qiao-zhi zhang Dan Zhou Jian-zhong Yin Hua-shu zhan State Key Laboratory of Fine Chemicals School of Chemical Machinery Dalian University of Technology Guizhou Aerospace Wujiang Electro-Mechanical Equipment Co. Ltd

Various agricultural crop residues including corn stover,corn cob,and sorghum stalk with a moisture content of 75 wt%were subjected to a long pretreatment(12–60 h)with supercritical CO_2(scCO_2),at low temperature(50–80°C)and a pressure of 17.5–25.0 *** sugar yields from the enzymatic hydrolysis(EH)of the pretreated samples were as much as three-to fourfold greater than those afforded by the raw ***,when pretreatment was conducted within a short time(e.g.0.5 h),as previously reported in the literature,only a slight increase in the EH sugar yields was *** proposed sc CO_2pretreatment mechanism demonstrated the role of moisture in the ***,softening,and swelling were observed to mainly affect the lignocellulose when a suitable amount of water was ***,the samples were analysed by X-ray diffraction and scanning electron microscopy,before and after pretreatment,to investigate the changes in the microscopic structure of the biomass.

关键词： Lignocellulose scCO2 pretreatment Enzymatic hydrolysis Sugar yield Moisture content

The inducible secreting TLR5 agonist,CBLB502,enhances the anti-tumor activity of CAR133-NK92 cells in colorectal cancer

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Cancer Biology & Medicine 2023年第9期20卷 662-681页

作者： Xiaohui Wang Wei Qiu Haoyu Liu min He Wei He zhan Li Zhiqiang Wu Xiang xu Ping Chen College of Biotechnology Southwest UniversityChongqing 400715China Department of Stem Cell&Regenerative Medicine State Key Laboratory of TraumaBurn and Combined InjuryDaping HospitalArmy Medical UniversityChongqing 400042China Department of Dermatology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325035China Department of Biotherapeutics The First Medical CenterChinese PLA General HospitalBeijing 100038China

Objective:CAR-T/NK cells have had limited success in the treatment of solid tumors,such as colorectal cancer(CRC),in part because of the heterogeneous nature of tumor-associated antigens that lead to antigen-negative relapse after the initial *** barrier might be overcome by enhancing the recruitment and durability of endogenous immune ***:Immunohistochemistry and flow cytometry were used to assess the expression of CD133 antigen in tissue microarrays and cell lines,*** vector transduction was used to generate CBLB502-secreting CAR133-NK92 cells(CAR133-i502-NK92).The tumor killing capacity of CAR133-NK92 cells in vitro and in vivo were quantified via LDH release,the RTCA assay,and the degranulation test,as well as measuring tumor bioluminescence signal intensity in mice ***:We engineered CAR133-i502-NK92 cells and demonstrated that those cells displayed enhanced proliferation(9.0×10^(4)cells vs.7.0×10^(4)cells)and specific anti-tumor activities in vitro and in a xenogeneic mouse model,and were ***,CBLB502 secreted by CAR133-i502-NK92 cells effectively activated endogenous immune ***,in hCD133+/hCD133−mixed cancer xenograft models,CAR133-i502-NK92 cells suppressed cancer growth better than the counterparts(n=5,P=0.0297).Greater T-cell infiltration was associated with greater anti-tumor potency(Pminating CD133-positive colon cancer cells in a CAR133-dependent manner and indirectly eradicating CD133-negative colon cancer cells in a CBLB502-specific endogenous immune response *** study describes a novel technique for optimizing CAR-T/NK cells for the treatment of antigenically-diverse solid tumors.

关键词： TLR5 agonist CBLB502 CAR133 endogenous immune response colorectal cancer