摘要：Cobalt nanoparticles(NPs)catalysts are extensively used in heterogeneous catalytic reactions,and the addition of alkali metal promoters is a common method to modulate the catalytic performance because the catalyst's surface structures and morphologies are sensitive to the addition of ***,the underlying modulation trend remains ***,the adsorption of alkali metal promoters(Na and K)on the surfaces of face-centered-cubic(FCC)and hexagonal-closest packed(HCP)polymorphous cobalt was systematically investigated using density functional ***,the effect of alkali promoters on surface energies and nanoparticle morphologies was revealed on the basis of Wulff *** FCC-Co,the exposed area of the(111)facet in the nanoparticle increases with the adsorption coverage of alkali metal ***,the(311),(110),and(100)facets would disappear under the higher adsorption coverage of alkali *** HCPCo,the Wulff morphology is dominated by the(0001)and(1011)facets and is independent of the alkali metal adsorption *** work provides insights into morphology modulation by alkali metal promoters for the rational design and synthesis of cobalt-based nanomaterials with desired facets and morphologies.

摘要：This paper presents a novel four degrees of freedom(DOF) parallel mechanism with the closed-loop limbs, which includes two translational(2 T) DOF and two rotational(2 R) DOF. By connecting the proposed parallel mechanism with the guide rail in series,the 5-DOF hybrid robot system is obtained, which can be applied for the composite material tape laying in aerospace industry. The analysis in this paper mainly focuses on the parallel module of the hybrid robot system. First, the freedom of the proposed parallel mechanism is calculated based on the screw theory. Then, according to the closed-loop vector equation, the inverse kinematics and Jacobian matrix of the parallel mechanism are carried out. Next, the workspace stiffness and dexterity analysis of the parallel mechanism are investigated based on the constraint equations, static stiffness matrix and Jacobian condition number. Finally, the correctness of the inverse kinematics and the high stiffness of the parallel mechanism are verified by the kinematics and stiffness simulation analysis, which lays a foundation for the automatic composite material tape laying.

摘要：In order to satisfy the requirements of large workspace and high dexterity for processing equipment of oversized cylindrical boxes′spherical crown surfaces in the aerospace industry,a novel serial-parallel hybrid processing robot mechanism is *** degrees of freedom of the 5PUS-(2UR)PU parallel mechanism are obtained by using the screw *** inverse kinematics of the hybrid mechanism are analyzed and the velocity Jacobian matrix is ***,the constraints of the main factors influencing workspace of the mechanism are given,and the position and posture workspace are ***,the dexterity and stiffness performance of the mechanism is analyzed based on the Jacobian *** virtual prototype is established,and the theoretical calculation and simulation analysis of the hybrid mechanism with arc curve as the processing trajectory are carried out by using Matlab and Adams *** research results show that the mechanism can satisfy the requirements of large workspace and high dexterity of oversized cylindrical boxes′spherical crown surface processing,and has feasibility and practical application value.

摘要：材料是有机体和无机体的起源,材料的历史可谓一个关于人类生存的历史。通过对于传统雕塑、绘画等艺术形式材质创造历史的梳理,透视艺术中的材质创造活动,将清晰地辩识人类对于存在之源的追问与探索。雕塑通过身体的触觉直接感知材料的物性,绘画则经由理性的思考,通过色彩寻找光的材料本性。然而,由于技术的限制,这种探索只能徘徊在感性与理性之间,无法从材料的生成过程去感知并创造材料的物性。当代虚拟现实技术,尤其是传感技术的发展,为艺术进入材料的微观运动,感知并展示材料生成现实世界各类有机体和无机体的材质提供了一种可能性,从而也创造了一种融合科学与艺术的新型媒介形式。

摘要：Ionic covalent organic framework(COF)materials with high specific surface areas and well-defined pore structures are desired for many applications yet seldom ***,we report a cationic pyridinium salt-based COF(PS-COF-1)with a Brunauer-Emmett-Teller(BET)surface area of 2703 m^(2) g^(-1),state-ofthe-art for an ionic *** by its ordered pore structure,chemical stability,and radiation resistance,PS-COF-1 showed exceptional adsorption properties toward aqueous ReO_(4)^(-)(1262 mg g^(-1))and ^(99)TcO_(4)^(-).Its adsorption performance surpassed its corresponding amorphous ***,PS-COF-1 exhibited fast adsorption kinetics,high adsorption capacities,and selectivity for ^(99)TcO_(4)^(-)and ReO_(4)^(-)at high ionic strengths,leading to the successful removal of ^(99)TcO_(4)^(-)under conditions relevant to low-activity waste streams at US legacy Hanford nuclear *** addition,PS-COF-1 can rapidly decontaminate ReO_(4)^(-)/^(99)TcO_(4)^(-)polluted potable water(~10 ppb)to drinking water level(0 ppb,part per billion)within 10 *** functional theory(DFT)calculations revealed PS-COF-1 has a strong affinity for ReO_(4)^(-)and ^(99)TcO_(4)^(-),thereby favoring adsorption of these low charge density anions over other common anions(e.g.,Cl^(-),NO_(3)^(-),SO_(4)^(2-),CO_(3)^(2-)).Our work demonstrates a novel cationic COF sorbent for selective radionuclide capture and legacy nuclear waste management.

摘要：Inorganic-organic hybrid materials are promising for application in the field of photocatalysis because of their excellent ***,their syntheses,mechanisms,and applications are reviewed in this ***,we introduce the role of inorganic-organic photocatalysts,their advantages and disadvantages,and their design ***,we present the top-down and bottom-up synthesis methods of the hybrid *** interaction between inorganic and organic components in hybrid materials is discussed,followed by how to improve inorganic-organic ***,the applications of hybrid materials in the field of photocatalysis,such as realizing hydrogen evolution,organic pollutant degradation,heavy metals and CO_(2) reduction,sterilization,and nitrogen fixation,are ***,the application prospects and development directions of inorganic-organic hybrid materials are explored and the unsolved problems are described.

摘要：Two new metal-organic frameworks（MOFs）,[Cu2（H_2O）_2（BCPIA）]（BUT-20）and（Me_2NH_2）[In（BCPIA）]（BUT-21）were designed and synthesized through the solvothermal reaction between a newly created desymmetric 4-connected ligand,5-（2,6-bis（4-carboxyphenyl）pyridin-4-yl）isophthalic acid（H_4BCPIA）and Cu（NO_3）2 2.5H_2O or In（NO_3）_3·5H_2O,respectively,and characterized by single-crystal and powder Xray diffraction,thermogravimetric analysis,infrared spectroscopy,and elemental *** two MOFs have three-dimensional structures,in which both the BCPIA 4 ligand and metal-containing entities,Cu_2（COO）_4（H_2O）_2 and In（COO）_4 act as 4-connected ***,different linkage configurations of the two metal-containing nodes,quadrilateral Cu_2_TD_2（COO）_4（H_2O）_2and tetrahedral In（COO）_4,lead to distinct structural networks of BUT-20 and 21,with Nbo and Unc topologies,respectively.

摘要：Achieving a strong redox ability and high visible-light absorption ability in a single semiconductor material is *** a heterojunction between two semiconductor materials is a feasible *** new step(S-scheme)heterojunction can effectively promote the separation and trans-fer of photogenerated electron-hole pairs and retain strong redox *** designed and pre-pared a Cd Se_(0.8)S_(0.2)-diethylenetriamine(DETA)/Sn Nb_(2)O_(6)heterostructure material via the sol-vothermal *** Cd Se_(0.8)S_(0.2)-DETA and Sn Nb_(2)O_(6)form an S-scheme heterojunction,30%Cd Se_(0.8)S_(0.2)-DETA/Sn Nb_(2)O_(6)exhibits the highest CO production rate(17.31μmol·g^(-1)·h^(-1)),which is factors of 2.8 and 4.8 higher than that of traditional solvothermal Sn Nb_(2)O_(6)(6.2μmol·g^(-1)·h^(-1))and Cd Se_(0.8)S_(0.2)-DETA(3.6μmol·g^(-1)·h^(-1)),respectively.X-ray photoelectron spectroscopy characterization data provided evidence that the transfer pathway of space charge in the CO_(2)reduction process was in accordance with the *** research provides a simple strategy through which one can optimize the band structure to promote the separation of photogenerated carriers and achieve a high efficiency of CO_(2)reduction.

摘要：Making a CAPP system which has both practicality and versatility is still a problem to be solved. Aiming at this problem, an idea of developing an integrated derivative and retrieved type of CAPP tool system is presented, and combined with a development practice. The structure and key technologies of the system are also introduced.

摘要：GaN-based laser diodes(LDs)extend the wavelength of semiconductor LDs into the visible and ultraviolet spectrum ranges,and are therefore expected to be widely used in quantum technology,bio&medical instruments,laser displays,lighting and materials *** development of blue and green LDs is still challenging,even though they are based on the sameⅢ-nitride materials as GaN-based lightemitting *** challenges and progress of GaN-based blue and green LDs are reviewed from the aspects of epitaxial growth and layer structure *** to large differences in lattice constants and growth conditions for InN,GaN,and AlN,considerable effort is required to improve the quality of InGaN multiple quantum well(MQW)gain medium for blue and especially green LDs.p-type doping profiles,conditions and layer structures are critical to reduce the internal losses and to mitigate the degradation of InGaN *** injection is also a key issue for GaN-based LDs.