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Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期 369-376页

作者： Song-Meng Wang Hao nian Yan-Fang Wang Li-Shuo Zheng Yu-Tao Zheng Yi-Wei Dong Liping Huang Xiaoping Wang Wei Jiang liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of n-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

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Dual sensitivity of spiropyran-functionalized carbon dots for full color conversions

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Science China Chemistry 2022年第11期65卷 2274-2282页

作者： Lin Ai Huimin liu Rui liu Haoqiang Song Ziqi Song Mingjun nie Geoffrey I.n.Waterhouse Siyu Lu Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450000China College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China School of Chemical Sciences The University of AucklandAuckland 142New Zealand

Multicolor phosphors that respond rapidly to external stimuli are highly desirable for many applications, including lighting,optical displays and sensors. Herein, spiropyran(SP)-functionalized carbon dots(CDs) were synthesized with a broad-spectrum output that were responsive to both ultraviolet(UV)/visible light and pH. The SP-CDs possessed strong ester linkages between the UV-absorbing/blue-emitting CDs and blue-absorbing/red-emitting surface SP groups, allowing efficient F?rster resonance energy transfer(FRET) between the donor and acceptor. UV irradiation or acid addition cause the SP ring opening to merocyanine(MC) or protonated MCH+forms, respectively, together with the formation of sheet-like aggregates. These processes enhanced the red emissions by the SP groups and attenuated blue emissions from the CDs. These changes were fully reversible under visible light or basic conditions, respectively, allowing dynamic regulation of the fluorescence properties(emission colors from blue to red, photoluminescence(PL) intensity) under photoirradiation on the timescale of minutes. As proof-of concept, we demonstrate that the emission properties of the SP-CDs can be used to construct UV and pH sensing materials as well as light emitting diode(LED) with different colors.

关键词： carbon dots dual-sensitivity full color emission spiropyran F?rster resonance energy transfer

Corrosion and cavitation erosion resistance enhancement of cast ni–Al bronze by laser surface melting

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Journal of Iron and Steel Research International 2022年第2期29卷 359-369页

作者： Q.n.Song Y.Tong H.L.Li H.n.Zhang n.Xu G.Y.Zhang Y.F.Bao W.liu Z.G.liu Y.X.Qiao Engineering Research Center of Dredging Technology of Ministry of Education Hohai UniversityChangzhou213022JiangsuChina College of Mechanical and Electrical Engineering Hohai UniversityChangzhou213022JiangsuChina College of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212003JiangsuChina

Laser surface melting (LSM) was applied on a cast ni–Al bronze (nAB), which was a crucial material for marine ship propellers. A 720 μm-thick LSM layer with fine equiaxed and dendritic microstructures was obtained. After immersion for 30 days, the corrosion rate of cast nAB was reduced by 25% after LSM. Preferential corrosion occurred and deep corrosion pits appeared at α + κIII microstructure for the cast nAB. LSM nAB underwent general corrosion, and a much more protective film formed on the surface because of the homogenized microstructure. The mass loss of the cast nAB was approximately 2.1 times larger than that of LSM nAB after cavitation erosion (CE) in 3.5 wt.% naCl solution for 5 h. For the two materials, the mechanical impact effect was dominantly responsible for CE damage. Therefore, the improved hardness and homogenized microstructure contributed to the improved CE resistance of LSM nAB. CE destructed the film, shifted the open circuit potential toward a more negative value, and raised the current density by an order of magnitude. Corrosion at the cast eutectoid microstructure and the dendrites of LSM nAB facilitates the degradation under the cavitation attack. CE-corrosion synergy was largely caused by corrosion-enhanced-CE.

关键词： Laser surface melting ni-Al bronze Microstructure Corrosion Cavitation erosion Synergy

An improved smoke-wire flow visualization technique using capacitor as power source

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Theoretical & Applied Mechanics Letters 2018年第6期8卷 378-383,I0004页

作者： n.Gao X.H.liu School of Aeronautics and Astronautics Dalian University of Technology

An improved smoke-wire flow visualization technique using a large capacitor as the power source was proposed. Electric current discharged from capacitors was used to heat a fine metal wire suspended in the flow field. The oil droplets attached to the wire were vaporized and smoke filaments followed the flow motions. A digital camera was used to record the images of the smoke filaments. The actions of discharging and camera shutter were triggered by signals from a microcontroller to ensure the accurate timing. Clear images of the streaklines were captured at a freestream velocity up to 12.9 m/s, much higher than the limits of the existing techniques.

关键词： Smoke-wire visualization Capacitor Timing circuit

Synthesis and Crystal Structure of (CO) 5ReSnMe 2Re(CO) 5

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Chinese Journal of Structural Chemistry 1999年第2期18卷 39-43页

作者： Li, J liu, H Song, XQ Kai, L Yin, n nankai Univ State Key Lab Elementoorgan Chem Tianjin 300071 Peoples R China nankai Univ Inst Elementoorgan Chem Tianjin 300071 Peoples R China

The crystal structure of the title complex (CO) 5ReSnMe 2Re(CO) 5, (C 12 H 6O 10 Re 2Sn, M r =801.27), has been determined by single crystal X ray diffraction. The crystal is monoclinic with space group P2 1/n (nO.14), a=10.587(2), b=12.392(2), c = 14.594(3) , β = 100.59(3)°, V = 1882(1) 3, D x = 2.828 g·cm -3 , F(000)=1432, μ =14.3759mm -1 , Z =4, and final R =0 0440 and R w =0 0483 for 1954 reflections ( I≥3σ(I )). In the complex the Sn atom is connected to two methyl groups and two Re atoms which are in slightly distorted tetrahedral arrangement. The Re atom is coordinated by five carbonyl ligands and one Sn atom, forming an octahedral structure.

关键词： metal carbonyl cluster Re complex synthesis crystal structure

Minimum Cost Multi-Path Parallel Transmission with Delay Constraint by Extending Openflow

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China Communications 2018年第3期15卷 15-26页

作者： Kuangyu Qin Chuanhe Huang n.Ganesan Kewei liu Xi Chen Computer School of Wuhan University Wuhan 430072 China Collaborative Innovation Center of Geospatial Technology Wuhan 430072 China School of Computer Science and Information Security Guilin University of Electronic Technology Guilin 541004 China Regional Institute of Co-operative Management Banashankari 2nd Stage Bangalore 560070 India

Sometimes user has the requirement to run a high bandwidth application over a low bandwidth network. But its implementation is not easy as the traditional network transmits data with only one path where its bandwidth is lower than the demand. Although the current network technology like SDn has the ability to precisely control the data transmission in the network, but till now the standard openflow protocol does not support splitting one flow to multiple flows. In this paper, a flow splitting algorithm is proposed. The algorithm splits a data flow to multiple sub-flows by extending the openflow protocol. A multiple paths routing algorithm is also proposed to implement the multi-path parallel transmission in the paper. The algorithm selects multiple paths and minimizes the cost of transmission under the constraint of maximum delay and delay variance. The simulations show the algorithms can significantly improve the transmission performance.

关键词： SDn OpenFlow multi-pathtransmission

Geographical Distribution and Morphological Variability of the Rapid Racerunner,Eremias velox (Pallas,1771)(Reptilia,Lacertidae) in the Eastern Periphery of Its Range

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Asian Herpetological Research 2019年第4期10卷 230-245页

作者： Marina A.CHIRIKOVA Tatjana n.DUJSEBAYEVA Jinlong liu Xianguang GUO Institute of Zoology Ministry of Education and SciencesAlmaty 050060Kazakhstan Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China

Phenotypic traits are usually correlated with the environment where organism occurs. In this study, the distribution of Eremias velox in the eastern periphery of its range was specified, and its morphological variation was analyzed. Linear dimensions, pholidosis, coloration and pattern features were compared among 135 specimens from nine populations inhabiting the Balkhash, Ili and Alakol basins, Junggar and Turpan depressions in the territory of Southeast Kazakhstan and Xinjiang, northwest China. The populations from the Junggar Depression(Kuytun, Shihezi and Urumqi) were characterized by higher mean values of linear characters, the number of scales across the middle of the body and gular, and were similar in the dominant coloration patterns. Small size, dark coloration and almost complete dominance of the striped-type coloration pattern among the specimens from the Alakol Lake islands seem to have an adaptive significance associated with the isolation of the population and type of their habitats. The subspecies Eremias velox roborowskii(endemic to the Turpan Depression) is elevated to species level, as supported by morphological divergence congruent with molecular and geographical data, including its peculiar type of coloration pattern, significantly lower amount of femoral pores and a higher percentage of specimens with one enlarged preanal scale(72.7%). These results together confirm a high degree of variability in morphology for ***х in the eastern periphery of its range, reflecting a complex orography and the existence of multiple geographical barriers in this territory.

关键词： Eremias velox Kazakhstan Xinjiang habitat pholidosis coloration intraspecies differentiation

A Model for Periodic nonlinear Electric Field Structures in Space Plasmas

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Communications in Theoretical Physics 2009年第7期52卷 149-154页

作者： M.n.S. Qureshi SHI Jian-Kui liu Zhen-Xing Department of Physics GC University Lahore 54000 Pakistan State Key Laboratory of Space Weather CSSAR Chinese Academy of Sciences Beijing 100080 China

In this study,we present a physical model to explain the generation mechanism of nonlinear periodic waveswith a large amplitude electric field structures propagating obliquely and exactly parallel to the magnetic ***'Sagdeev potential' from the MHD equations is derived and the nonlinear electric field waveforms are obtained when theMach number,direction of propagation,and the initial electric field satisfy certain plasma *** the parallelpropagation,the amplitude of the electric field waves with ion-acoustic mode increases with the increase of initial electricfield and Mach number but its frequency decreases with the increase of Mach *** amplitude and frequency ofthe electric field waves with ion-cyclotron mode decrease with the increase of Mach number and become less spiky,andits amplitude increases with the increase of initial electric *** the oblique propagation,only periodic electric fieldwave with an ion-cyclotron mode obtained,its amplitude and frequency increase with the increase of Mach number andbecome *** our model the electric field structures show periodic,spiky,and saw-tooth behaviours correspondingto different plasma conditions.

关键词： nonlinear waves electric field solitary structures

Convergence Analysis of Iterative Sequences for a Pair of Mappings in Banach Spaces

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Acta Mathematica Sinica,English Series 2008年第3期24卷 463-470页

作者： liu Chuan ZEnG n.C.WOnG J.C.YAO Department of Mathematics Shanghai Normal University Shanghai 200234 P. R. China Department of Applied Mathematics National Sun Yat-Sen University Kaohsiung Taiwan 80424

Let C be a nonempty closed convex subset of a real Banach space E. Let S ： C→ C be a quasi-nonexpansive mapping, let T ： C→C be an asymptotically demicontractive and uniformly Lipschitzian mapping, and let F ：= {x ∈C ： Sx = x and Tx = x}≠Ф Let {xn}n≥0 be the sequence generated irom an arbitrary x0∈Cby xn＋i=（1-cn）Sxn＋cnT^nxn, n≥*** prove the necessary and sufficient conditions for the strong convergence of the iterative sequence {xn} to an element of F. These extend and improve the recent results of Moore and nnoli.

关键词： quasi-nonexpansive mapping asymptotically demicontractive type mapping iterative sequence convergence analysis