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Science China Chemistry 2025年

作者： Jun-Qiang Chen Qiao-Hong Li Qin-Long Hong ping shao Hai-Xia Zhang Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Single-atom catalyst has garnered widespread attention to mimic mature enzymes due to its well-defined atomic structure and coordination environments. However, since the carbon–carbon（C–C） coupling reactions require synergistic catalysis of multiple sites, single-atom catalysts suffer from insufficient active sites and unclear reaction mechanisms. Controlling the reaction intermediates in a precisely targeted pocket through careful metal–organic cage design is therefore crucial. Here, we prepare a tetrahedral [Cu6L4]-type boron–imidazolate cage integrating highly active Cu sites and optimized cavity, which exhibits enzyme like specific catalytic performance in electrochemical CO2reduction reaction（CO2RR） to enhance the selectivity of *** analyses and computational calculations suggest that the single Cu site together with neighboring boron–imidazolate ligands provides suitably synergistic effects that enable the energetically favorable formation of an *COCHO intermediate, a key step determining selectivity. As a result, the [Cu6L4]-type cage of BIC-145 achieves a Faradaic efficiency of 28% for C2H4maintaining an average current density of -3.54 mA cm-2over a 5-hour electrolysis period. This work represents the first example for studying single-metal site catalysts with ultra-low coordination numbers through the rational design of metal–organic cages.

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Enhanced separation of Pd(Ⅱ)and Pt(Ⅳ)from hydrochloric acid aqueous solution using 2-((2-methoxyethyl)thio)-1H-benzimidazole

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Rare Metals 2020年第12期39卷 1473-1482页

作者： shao-ping Feng Kun Huang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Department of Chemistry College of ScienceHonghe UniversityMengzi 661199China

Separation of palladium(Pd)and platinum(Pt)by solvent extraction is difficult because of their extremely similar physicochemical *** of new extractants with a high extraction efficiency and excellent separation selectivity is the primary focus for enhancing the separation of Pd and Pt by solvent *** this study,a new extractant,2-((2-methoxyethyl)thio)-1 H-benzimidazole(MOBI),which contains N,S,and O atoms,was synthesized and used to separate Pd(Ⅱ)and Pt(Ⅳ)from a hydrochloric acid aqueous *** experimental results revealed that Pd(Ⅱ)and Pt(Ⅳ)were effectively separated under the optimal conditions:MOB I concentration of 0.005 mol·L^(-1),HCl concentration of0.2 mol·L^(-1),organic/aqueous(O/A)phase ratio of 1.0,and contact time of 15 *** separation coefficient between Pd(Ⅱ)and Pt(Ⅳ)was 1246.40,which indicates that MOBI has a higher selectivity for Pd(Ⅱ)than Pt(Ⅳ).In addition,the mechanism of coordination between Pd(Ⅱ)and MOBI was demonstrated through the slope method,Fourier transform infrared spectroscopy(FTIR),hydrogen-1 nuclear magnetic resonance spectroscopy(^(1)H NMR),and carbon-13 nuclear magnetic resonance spectroscopy(^(13)C NMR).The results revealed that MOBI could coordinate with Pd(Ⅱ)via the N atom in the benzimidazole ring of MOBI molecules to form[Pd(MOBI)_(2)Cl_(2)](O).

关键词： 2-((2-methoxyethyl)thio)-1H-benzimidazole Palladium Platinum Extraction Separation

Incipient plasticity and activation volume of dislocation nucleation for TiZrNbTaMo high-entropy alloys characterized by nanoindentation

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Journal of Materials Science & Technology 2019年第5期35卷 812-816页

作者： shao-ping Wang Jian Xu Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China University of Chinese Academy of Sciences 19(A) Yuquan Road Beijing 100049 China

With instrumented nanoindentation, incipient plasticity of two as-cast BCC TiZrNbTa and TiZrNbTaMo high-entropy alloys(HEAs) are investigated in terms of pop-in events during loading, to characterize the dislocation behavior in these solid-solution alloys. It is shown that the maximum shear stress (max)required for dislocation nucleation is determined to be 1/16-1/12 and 1/18-1/14 of shear modulus for the TiZrNbTa and TiZrNbTaMo HEAs, respectively, which is nearly comparative to the theoretical shear stress of these alloys. The activation volumes of dislocation nucleation the TiZrNbTa and TiZrNbTaMo HEAs are determined to be 1.2 b^3 for and 1.3 b^3, respectively, which is substantially irrespective of alloying with Mo. Furthermore, activation volumes of these two HEAs are on the order of cubic burger’s vector and only one-third of the value for TiZrHfNb HEA, suggesting that a heterogeneous nucleation of dislocation took place in a way of direct atom-vacancy exchange, rather than of the cooperative motion of several atoms. These findings reveal the unique feature in deformation of BCC solid-solution complex alloys.

关键词： High-entropy alloys Nanoindentation Refractory metals BCC phase Incipient plasticity

A Heat Transport Model Including the Effect of Non-Maxwellian Electron Distribution and Its Application in Laser Produced Plasma

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Chinese Physics Letters 1999年第7期16卷 520-522页

作者： ZHU shao-ping GU Pei-jun Institute of Applied Physics and Computational Mathematics Beijing 100088

An electron heat transport model is given for studying laser-to-x-ray conversion of inertial confinement *** electron heat flux is derived based on a non-Maxwellian electron distribution,and the behavior of the heat flux is *** effect of the non-Maxwellian electron distribution on inverse bremsstrahlung heating rate and electron-ion heat transfer rate are also included in the present *** simulation results show that the effects of the non-Maxwellian electron distribution on laser absorption efficiency,laser-to-x-ray conversion efficiency and electron temperature in the coronal region are important.

关键词： Maxwell Electron distribution

Nonlinear Acoustic-Optical Effect and Extraordinary Diffraction Distribution in Liquid Surface

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Chinese Physics Letters 2013年第12期30卷 67-70页

作者： MIAO Yang WANG shao-ping School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191

Nonlinear acoustic-optical effect is discovered by using a low-frequency liquid surface acoustic wave with great *** are higher harmonics in diffracted light and the intensity of the higher harmonic has the relation of Bessel's function with the *** light patterns diffracted by the wave can be classified into the ordinary and extraordinary beams which are corresponding to small and great amplitudes of the *** ordinary and extraordinary patterns are observed experimentally and the critical amplitude value is found.

关键词： ordinary Nonlinear wave

Ligand-controlled NiH-catalyzed regiodivergent hydroalkylation of 2-alkenylazaarenes

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Science China Chemistry 2024年第6期67卷 1935-1940页

作者： Ya-ping shao Zhuo-Min Chi Yong-Min Liang State Key Laboratory of Applied Organic Chemistry School of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China

A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor *** method enables the synthesis of diverseβ-orγ-branched aromatic *** mild regiodivergent protocols exhibit wide substrate scope,excellent functional tolerance,and great reaction yield with remarkable ***,deuterium labeling studies reveal Ni H-catalyzed interrupted chain-walking mode as the mechanism behind remotedβ-selective hydroalkylation reaction—an interesting phenomenon mediated through aromatic imine directing groups.

关键词： NiH regiodivergent hydroalkylation azaarenes interrupted chain-walking

Wind induced deformation and vibration of a Platanus acerifolia leaf

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Acta Mechanica Sinica 2012年第3期28卷 583-594页

作者： Chuan-ping shao Ye-Jun Chen Jian-Zhong Lin China Jiliang University 310018 HangzhouChina

Deformation and vibration of twig-connected sin- gle leaf in wind is investigated experimentally. Results show that the Reynolds number based on wind speed and length of leaf blade is a key parameter to the aerodynamic prob- lem. In case the front surface facing the wind and with an in- crease of Reynolds number, the leaf experiences static defor- mation, large amplitude and low frequency sway, reconfigu- ration to delta wing shape, flapping of tips, high frequency vibration of whole leaf blade, recovery of delta wing shape, and twig-leaf coupling vibration. Abrupt changes from one state to another occur at critical Reynolds numbers. In case the back surface facing the wind, the large amplitude and low frequency sway does not occur, the recovered delta wing shape is replaced by a conic shape, and the critical Reynolds numbers of vibrations are higher than the ones correspond- ing to the case with the front surface facing the wind. A pair of ram-horn vortex is observed behind the delta wing shaped leaf. A single vortex is found downstream of the conic shaped leaf. A lift is induced by the vortex, and this lift helps leaf to adjust position and posture, stabilize blade distortion and reduce drag and vibration.

关键词： Tree leaf. Wind. Deformation Vibration

Bulk Metallic Glasses: MRI Compatibility and Its Correlation with Magnetic Susceptibility

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Journal of Materials Science & Technology 2016年第6期32卷 496-504页

作者： Da-Bo Zhou shao-ping Wang shao-Gang Wang Hong-Jun Ai Jian Xu School of Stomatology China Medical University Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

Several bulk metallic glasses （BMGs） were selected to in vitro assess their magnetic resonance imaging （MRI） compatibility with agarose gel as a phantom, in terms of the extent of susceptibility artifacts in magnetic resonance image. The investigated metals include the ***2.3Cu26.9Si16.3, Zr61Ti2Cu2sA112, Cu50.4Nis.0Ti31Zr13 and Ti47Cu38Zr7.5Fe2.5Sn2Si1Ag2, together with pure titanium （CP-Ti） and Co-28Cr-6Mo alloy （ASTM-F799） for comparison. The artifact extent in MR images was quantitatively characterized according to the total volume in reconstructed 3D images with a series of slices under acquisition by fast spin echo （FSE） sequence and gradient echo （GRE） sequence. As indicated, artifact severity of the BMGs is much less than that of the CoCrMo alloy. The AuAgPdCuSi BMG manifested the smallest arti- fact among the four BMGs, while the TiCuZrFeSnSiAg BMG is comparative to the CP-Ti. The MRI compatibility of BMGs is ranked as a sequence of the Au-, Zr-, Cu- and Ti-based alloys. Dependence of material mag- netic susceptibility on artifact extent is also the case of the BMGs, even though it does not follow a simple linear relationship within a range of △χv = 30-180 ppm. These findings are of interest to reveal that the BMGs are potentially applied in the fields associated with an interventional MRI for MRI-guided surgeries.

关键词： Metallic glass MRI compatibility Magnetic susceptibility Metal-induced artifacts Biomaterials

Towards natural object-based image recoloring

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Computational Visual Media 2022年第2期8卷 317-328页

作者： Meng-Yao Cui Zhe Zhu Yulu Yang shao-ping Lu TKLNDST CSNankai UniversityTianjin 300350China Department of Radiology Duke UniversityDurhamNC 27705USA

Existing color editing algorithms enable users to edit the colors in an image according to their own *** artists who have an accurate grasp of color,ordinary users are inexperienced in color selection and matching,and allowing non-professional users to edit colors arbitrarily may lead to unrealistic editing *** address this issue,we introduce a palette-based approach for realistic object-level image *** data-driven approach consists of an offline learning part that learns the color distributions for different objects in the real world,and an online recoloring part that first recognizes the object category,and then recommends appropriate realistic candidate colors learned in the offline step for that *** also provide an intuitive user interface for efficient color *** color selection,image matting is performed to ensure smoothness of the object *** evaluation on various color editing examples demonstrates that our approach outperforms existing state-of-the-art color editing algorithms.

关键词： color editing object recognition color palette representation natural color

Metal-organic frameworks for electrochemical reduction of carbon dioxide: The role of metal centers

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Journal of Energy Chemistry 2020年第1期29卷 156-170,I0006页

作者： ping shao Luocai Yi Shumei Chen Tianhua Zhou Jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002FujianChina College of Chemistry Fuzhou UniversityFuzhou 350002FujianChina

Direct electrochemical reduction of CO2 into valuable chemicals and fuel is one of the most promising approaches to address the current energy crisis and lower CO2 ***,numerous metal-organic framework(MOF)and their derived materials have extensively been developed as electrocatalysts for CO2 reduction owing to their unique structure including porosity,large specific surface area,and tunable chemical *** this review,the recent progress of MOF-based electrocatalysts for CO2 reduction was summarized and *** discussions mainly focus on the synthesis and mechanism of pristine MOFs and MOF-derived materials for electrocatalytic CO2 *** examples are expected to provide clues to rational design and synthesis of stable and high-performance MOFs-based electrocatalysts for CO2 reduction.

关键词： Metal organic framework Electrocatalyst Carbon dioxides Reduction reaction Nanomaterials