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Chemical Research in Chinese Universities 2018年第3期34卷 363-368页

作者： MA lian XU Bin liu Leijing tian Wenjing State Key Laboratory of Supramolecular Structure and Materials Jilin University Changehun 130012 P. R. China

A label-free fluorescent aptasensor for specific and ultrasensitive monitoring ochratoxin A（OTA） was developed using the specific aptamer of OTA（OSA） as recognition dement, an aggregation-induced emission（AIE） molecule（a 9,10-distyrylanthracene with two ammonium groups, DSAI） as a fluorescent probe, and graphene oxide（GO） as a quencher. In the absence of OTA, the AIE probe DSAI and OSA complex（DSAI/OSA） is adsorbed on the GO surface, and the fluorescence of DSAI will be quenched efficiently via the fluorescence resonance energy transfer（FRET） from DSAI to GO. Upon the OTA addition, a more stable complex（OSA-OTA） is formed and released from GO. Meanwhile, DSAI and OSA-OTA can form a new complex（DSAI/OSA-OTA）, then the fluorescent signal of DSAI recovers gradually. Therefore, by introducing GO and DSAI, the fluorescence signal of DSAI can be easily turned from ＂off＂ to ＂on＂ after the addition of OTA, and the ultrasensitive detection of OTA by monitoring the change of the fluorescence signal of DSAI can be readily realized. The detection limit of the assay can reach 0.324 nmol/L with a linear detection range of 10-200 nmol/L. And the aptasensor exhibits high selectivity for OTA against other analogues. Moreover, it has been successfully applied for the detection of OTA in red wine samples.

关键词： Label-free Aptasensor Aggregation-induced emission(AIE)-active probe Graphene oxide Ochratoxin A

Mutation of DELAYED GREENING1 impairs chloroplast RNA editing at elevated ambient temperature in Arabidopsis

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Journal of Genetics and Genomics 2020年第4期47卷 201-212页

作者： Jingliang Sun Yingying tian Qichao lian Jian-Xiang liu State Key Laboratory of Genetic Engineering School of Life SciencesFudan UniversityShanghai200433China State Key Laboratory of Plant Physiology and Biochemistry College of Life SciencesZhejiang UniversityHangzhou310027China

Chloroplasts are important for plant growth and *** editing in chloroplast converts cytidines(Cs)to uridine s(Us)at specific transcript positions and provides a correction mechanism to restore conserved codons or creates start or stop ***,the underlined molecular mechanism is not yet fully unders *** the present study,we identi fied a thermo-sensi tive mutantin leaf color 1(tst1)and found that TSL1 is allelic to DELAYED GREENING 1(DG1).The mis sense mutation of DG1 in tsl1 mutant confers a high temperature sensitivity and impaired chloroplast development at an elevated ambient temperature in *** analysis showed that chloroplast RNA editing at seve ral sites including accD-2568,ndhD-2,and petL-5 is impaired in tsl1 mutant plants grown at an elevated ***1 interacts with MORF2 and other proteins such as DYW1 and DYW2 involved in chloroplast RNA *** vitro RNA electrophoretic mobility shift assay demonstrated that DG1 binds to RNA targets such as accD,ndhD,and ***,our results revealed that DG1 is important for maintaining chloroplast mRNA editing in Arabidopsis.

关键词： Chloroplast development mRNA editing Warm temperature

Upper Bound Solution of the Resisting Moment Bearing Capacity of A Composite Bucket Shallow Foundation of An Offshore Wind Turbine in Sand

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China Ocean Engineering 2022年第6期36卷 859-870页

作者： liu Run LI tian-liang CHEN Guang-si lian Ji-jian State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

Bearing the large moment that is generated by the wind load that acts on the upper structure of offshore wind turbines is an important feature of their foundations that is different from other offshore structures.A composite bucket shallow foundation(CBSF)has been proposed by tian.in.University to address the soft geological conditions in the offshore regions of China for wind *** CBSF is a new type of foundation and is effective against large *** soil deformation test of a CBSF and the numerical simulation study under the same working conditions are carried out to determine the failure mechanism of a CBSF under moment *** resisting soil compression rateηm is defined as a new empirical parameter that indicates the ability of the soil inside the bucket to resist moment *** upper limit of the resisting moment bearing capacity of the bucket foundation is derived through the upper bound theorem of classical plasticity theory based on the failure *** calculation method is validated by tests of bucket models with different height-diameter ratios in sand under moment loading.

关键词： bucket foundation failure mechanism resisting moment bearing capacity upper bound theorem resisting soil compression rate

DeepSI:A Sensitive-Driven Testing Samples Generation Method of Whitebox CNN Model for Edge Computing

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Tsinghua Science and Technology 2024年第3期29卷 784-794页

作者： Zhichao lian Fengjun tian School of Cyber Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

In recent years,Deep Learning(DL)technique has been widely used in Internet of Things(IoT)and Industrial Internet of Things(IIoT)for edge computing,and achieved good *** more and more studies have shown the vulnerability of neural ***,it is important to test the robustness and vulnerability of neural *** specifically,inspired by layer-wise relevance propagation and neural network verification,we propose a novel measurement of sensitive neurons and important neurons,and propose a novel neuron coverage criterion for robustness *** on the novel criterion,we design a novel testing sample generation method,named DeepSI,which involves definitions of sensitive neurons and important ***,we construct sensitive-decision paths of the neural network through selecting sensitive neurons and important ***,we verify our idea by setting up several experiments,then results show our proposed method achieves superior performances.

关键词： neuron sensitivity Layer-wise Relevance Propagation(LRP) neural network verification deeplearning testing

Mean Residence Time of CO2 Molecules in Flexible ZIF-8 Cages Explored by Molecular Dynamics Simulations

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Chinese Journal of Chemical Physics 2013年第5期26卷 553-557,I0003页

作者： Zhen Yang lian liu tian Gui Rong-fei Zhou Xiang-shu Chen College of Chemistry and Chemical Engineering JianExi Inorganic Membrane Materials EngineeringResearch Center Jiangxi Normal University Nanchang 330022 China

The adsorption sites and diffusion mechanism of CO2 molecules in the flexible Zn（MeIM）2 （MeIM=2-methylimidazole）（ZIF-8） have been investigated by grand canonical Monte Carlo and molecular dynamics simulations. A reasonable time correlation function is for the first time constructed to explore the mean residence time of CO2 molecules in the ZIF-8 cages, suggesting that C02 molecules can remain in the same cage for up to several tens of picoseconds. Furthermore, we find that the mean residence time almost linearly increases with the increasing pressure （or loading） at 273 and 298 K.

关键词： Diffusion Adsorption Carbon dioxide Zeolitic imidazolate frameworks Molecular dynamics simulation

Synthesis and Crystal Structure of 4,4′-Diamino-N,N′-diethyl Bisbenzenesulfamide

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Chinese Journal of Structural Chemistry 2007年第2期26卷 177-183页

作者： WANG Li-Min PAN Xiao-Juan FAN Zhao-Yu YANG liu-Bo liu lian tian He Laboratory for Advanced Materials Institute of Fine ChemicalsEast China University of Science and Technology Shanghai 200237 China

A new compound of 4,4＇-diamino-N,V＇-diethyl bisbenzenesulfamide （C18H26N4O4S2, Fw = 426.55） has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to the monoclinic system, space group P21/c with a = 10.0623（9）, b = 13.6759（13）, c =15.5309（14） A, β = 100.482（2）°, V= 2101.6（3） A^3, Dc = 1.348 g/cm^3, F（000） = 904, μ = 0.285 mm^-1, Z = 4, the final R = 0.0512 and wR = 0.1363 for 3485 observed reflections with I 〉 2σ（I）. The structure of the title compound is pseudo secondary axisymmetric, and the two sulfamide-groups show distorted tetrahedral configurations.

关键词： 4,4'-diamino-N,V'-diethyl bisbenzenesulfamide synthesis crystal structure

Semi-analytical method of calculating the electrostatic interaction of colloidal solutions

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Chinese Physics B 2017年第1期26卷 471-481页

作者： Hongqing tian Zengju lian Faculty of Science Ningbo University Ningbo 315211 China

We present a semi-analytical method of calculating the electrostatic interaction of colloid solutions for confined and unconfined systems. We expand the electrostatic potential of the system in terms of some basis functions such as spherical harmonic function and cylinder function. The expansion coefficients can be obtained by solving the equations of the boundary conditions, combining an analytical translation transform of the coordinates and a numerical multipoint collection method. The precise electrostatic potential and the interaction energy are then obtained automatically. The method is available not only for the uniformly charged colloids but also for nonuniformly charged ones. We have successfully applied it to unconfined diluted colloid system and some confined systems such as the long cylinder wall confinement, the air–water interfacial confinement and porous membrane confinement. The consistence checks of our calculations with some known analytical cases have been made for all our applications. In theory, the method is applicable to any dilute colloid solutions with an arbitrary distribution of the surface charge on the colloidal particle under a regular solid confinement, such as spherical cavity confinement and lamellar confinement.

关键词： Poisson–Boltzmann equation like-charged attraction basis function expansion multipoint collection method

Cutting Force Fluctuation Suppression and Error Homogenization of Noncircular Gear Hobbing Based on the Tool Shifting Method

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 167-179页

作者： Dazhu Li Jiang Han Xiaoqing tian lian Xia Institute of Artificial Intelligence Anhui Polytechnic UniversityWuhu 241000China CIMS Institute Hefei University of TechnologyHefei 230009China

The current research on noncircular hobbing mainly focuses on the linkage model and motion ***,the intermittent cutting characteristics of hobbing would increase uncertainties in the manufacturing *** this paper,a hobbing machining model with tool-shifting characteristics was proposed to solve the problems of cutting force fluctuation and inconsistency of tooth profile envelope accuracy at different positions of the pitch curve in noncircular gear *** on the unit cutting force coefficient method,the undeformed chip volume generated by interrupted cutting was used to characterize the fluctuation trend of the hobbing *** fluctuation characteristics of the cutting force generated by different hobbing models were compared and *** the equivalent gear tooth and hob slotting numbers,an analysis model of the tooth profile envelope error of the noncircular gear was ***,the tooth profile envelope errors at different positions of the pitch curve were compared and analyzed based on the constructed *** transmission structure of the electronic gearbox was constructed based on the proposed hobbing model,and the hobbing experiment was conducted based on the selfdeveloped noncircular gear CNC hobbing *** paper proposes a hobbing method that can effectively suppress the fluctuation of the peak and whole circumference cutting force and reduce the maximum envelope error of the whole circumference gear teeth.

关键词： Noncircular gear Gear hobbing Cutting force Envelope error Machining model

Fiber Traction Printing:A 3D Printing Method of continuous Fiber Reinforced Metal Matrix Composite

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Chinese Journal of Mechanical Engineering 2020年第2期33卷 69-79页

作者： Xin Wang Xiaoyong tian Qin lian Dichen Li State Key Laboratory of Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’an 710049China Shaanxi Engineering Research Center for Rapid Manufacturing Technology Xi’an 710049China

A novel metal matrix composite freeform fabrication approach,fiber traction printing(FTP),is demonstrated through controlling the wetting behavior between fibers and the *** process utilizes the fiber bundle to control the cross-sectional shape of the liquid metal,shaping it from circular to rectangular which is more *** FTP process could resolve manufacturing difficulties in the complex structure of continuous fiber reinforced metal matrix *** printing of the first layer monofilament is discussed in detail,and the effects of the fibrous coating thickness on the mechanical properties and microstructures of the composite are also investigated in this *** composite material prepared by the FTP process has a tensile strength of 235.2 MPa,which is close to that of composites fabricated by conventional *** complex structures are printed to demonstrate the advantages and innovations of this ***,the FTP method is suited to other material systems with good wettability,such as modified carbon fiber,surfactants,and aluminum alloys.

关键词： 3D printing Metal matrix composite Capillarity continuous carbon fiber

Identification of the Flavone in the Flower Bud of Panax Quinquefolium and Its content Determination in the Different Parts

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Chemical Research in Chinese Universities 2001年第1期17卷 121-126页

作者： MENG Xiang-ying LI Xiang-gao tian Yi-xin liu Yin-yan ZHENG lian-xiu College of Chinese Medical Material Jilin Agricultural UniversityChangchun 130118P.R.China The School of Basic Medical Sciences Norman Bethune University of Medical SciencesChangchun 130021P.R.China People Hospital of Jilin Province Changchun 130021P.R.China

Chemical constituents namely flavonoids in the flower buds of Panax quinque folium were identified and their content was determined in different parts. The content determination was performed using dual wavelength TLC-scan and ultraviolet absorption. content determination results showed that the content of flavonoid in the flower bud was higher than in the roots.

关键词： Panax quinquefulium Flower buds Flavonoid Root Fruit