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Cathodic process of nickel electrodeposition from ammonia-ammonium chloride solutions

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Rare Metals 2023年第3期42卷 1061-1066页

作者： Liang Yuan Zhi-Ying Ding Shi-Jun Liu ya-ning he School of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China

Mechanism of cathodic process on nickel electrodeposition from ammonia-ammonium chloride solutions was studied by Tafel polarization curves,linear sweep voltammetry(LSV),cyclic voltammograms(CV)and chronopotentiometry(CE)*** the electrolyte with 1.0 mol·L^(-1) NiCl_(2)·6H_(2)O,4.0 mol·L^(-1) NH_(3)·H_(2)O and2.5 mol·L^(-1) NH4Cl,nickel ion mainly complexed with ammonia and almost no free nickel ion could be *** is confirmed that the dominant form of nickel ammonia complex ion in the system is Ni(NH_(3))_(4)^(2+)by measuring the equilibrium potential of the electrode at various concentrations of *** species of Ni(NH_(3))42+turns into Ni(NH_(3))_(2)^(2+)during pre-chemical reaction step before discharging reduction ***,Ni(NH_(3))_(2)^(2+)discharges at the cathodic interface to form metal nickel deposit *** process is involved during nickel electrodeposition according to CV *** reduction reaction of Ni(NH_(3))_(2)^(2+)is irreversible which is controlled by diffusion *** processes are also accompanied during the electrodeposition process,except for the diffusioncontrolled process.

关键词： Electrodeposition Nickel Cathodic process Ammoniacal solution

Synthesis, self-assembly and photo-responsive behavior of AB_2 shaped amphiphilic azo block copolymer

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Chinese Chemical Letters 2015年第7期26卷 857-861页

作者： Ren-Bo Wei Xiao-Gong Wang ya-ning he Department of Chemical Engineering Key Laboratory of Advanced Materials (MOE) Tsinghua University

In this work, we report the synthesis of AB2 shaped amphiphilic azo block copolymer by macromolecular azo coupling reaction. The product and intermediates were characterized by various methods. The self- assembly in selected solvents and photo-responsive behavior of the copolymer were studied by means of UV-vis spectrophotometry and TEM. Spherical aggregates can be obtained by gradually adding water into the solution of this amphiphilic azo block copolymer. Upon irradiation with polarized UV （365 nm） light, the aggregates can be elongated in the polarized direction.

关键词： Azo block copolymerSelf-assemblySpherical aggregatesPhotoinduced deformationMacromolecular azo-coupling reaction

Cinnamate-functionalized hyperbranched polymer as liquid crystal photo-alignment layer

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Chinese Chemical Letters 2008年第9期19卷 1131-1134页

作者： Bin Jun Shen Zheng Xie ya ning he yan Qing Lian Institute of Polymer Research Department of Chemical Engineering Laboratory of Advanced Materials Tsinghua University Beijing 100084 China

In this work, 4-methoxylcinnamoyl chloride was reacted with a commercial hyperbranched polymer （Boltom-TM H30） to prepare a hyperbranched photosensitive polymer （H30-Ci）. The polymer was characterized by UV absorption spectrum and 1H- NMR spectrum. After processed by Linearly Polarized Polymerization （LPP） method, the spin-coated films of H30-Ci were used as photo-alignment layers to assemble liquid crystal （LC） cells containing nematic liquid crystal （5CB）. The observation by polarized microscope showed that the H30-Ci blended with a linear polymer （BP-AN-Ci） photo-alignment layers could align LC molecules in a very uniform way.

关键词： Hyperbranched polymer Photo-alignment layer Linearly polarized polymerization (LPP) Liquid crystal display

Morphology and Crystalline Structure of Inclusion Compounds Formed between Poly(ethylene glycol) and Urea

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Chinese Journal of Polymer Science 2014年第9期32卷 1234-1242页

作者： Da-wei Lin Zhi Zhong Yi-ren Tang yang Gao ya-ning he Bao-hua Guo 徐军 Institute of Polymer Science & Engineering Department of Chemical Engineering Tsinghua University

The poly（ethylene glycol）（PEG, with Mw 2000）-urea inclusion compound （IC） crystallized at high temperature region showed two typical orientations, flat-on and edge-on crystals. 2D-XRD and polarized FTIR spectroscopy revealed that the PEG chains within urea channels were perpendicular to the substrate in fiat-on oriented crystals, while PEG chain axes were parallel to the substrate and lay along the growth direction in the edge-on crystals. FT1R absorption bands of PEG in the ICs are sensitive to orientation of the crystals. A scheme of PEG chain packing in the urea IC channel was proposed, which could explain the orientation of the crystal nucleus causing the two types of morphologies. Furthermore, functioning of PEG2000 chain end with analine had significantly influence on the morphology and orientation of the inclusion compound crystals, due to the defects caused by large terminal groups included in the urea channel.

关键词： Poly(ethylene glycol) Urea Inclusion compounds Morphology Orientation.

Effects of additives on zinc electrodeposition from alkaline zincate solution

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Transactions of Nonferrous Metals Society of China 2017年第7期27卷 1656-1664页

作者： Liang YUAN Zhi-ying DING Shi-jun LIU Wei-fa SHU ya-ning he School of Chemistry and Chemical Engineering Central South University Changsha 410083 China 8511 Research Institute of China Aerospace Science & Industry Group Nanjing 210017 China

The effects of additives on the surface and cross-sectional morphologies of zinc deposits on iron substrate from alkalinezincate solution were characterized by scanning electron microscope(SEM).The cathodic reaction mechanisms under variousconcentrations of additives were investigated using cyclic voltammetry(CV)and electrochemical impedance spectroscopy(EIS)*** is found that with increasing the additive A content in the bath solution,the nucleation overpotential(NOP)value isobviously increased and the inhibition effect is *** may be mainly due to the adsorption of additive A on the cathodicelectrode surface,which can cover the active sites and block the discharge *** results of EIS analysis indicate that therate-determining step of zinc electrodeposition process is changed from mixed control step into electrochemical reduction step in thepresence of additive ***,any quantity of additive B has little effect on the NOP value and the inhibition effect is not ***,addition of additive A and additive B at the same time displays the strongest inhibition effect and shows a strongsynergism because of their co-adsorption on the cathodic electrode surface.

关键词： electrodeposition zinc additives alkaline zincate solution morphology

Bioinformatics analysis of breast cancer bone metastasis related geneCXCR4

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Asian Pacific Journal of Tropical Medicine 2013年第9期6卷 732-738页

作者： heng-Wei Zhang Xian-Fu Sun ya-ning he Jun-Tao Li Xu-Hui Guo Hui Liu Department of Breast Henan Cancer Hospital Affiliated Cancer Hospital of Zhengzhou University

Objective:To analyze breast cancer bone metastasis related ***:This research screened breast cancer bone metastasis related genes by high-flux gene ***:It was found that the expressions of 396 genes were different including 165 up-regulations and 231 *** expression of chemokine receptor CXCR4 was obviously upregulated in the tissue with breast cancer bone *** with the tissue without hone metastasis,there was significant difference,which indicated that CXCR4 played a vital role in breast cancer bone ***:The hioinformatics analysis of CXCR4 can provide a certain basis for the occurrence and diagnosis of breast cancer bone metastasis,target gene therapy and evaluation of prognosis.

关键词： Breast cancer bone metastasis CXCR4 Bioinformatics analysis

Adverse effect of niobium and boron on hot deformation behavior of sulfur-containing steel

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Journal of Iron and Steel Research International 2024年第1期31卷 252-263页

作者： Guo-ning he Shi-qi Wan Bo Jiang Chao-lei Zhang ya-zheng Liu Chun-jing Wu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were *** compression and tenssion tests were carried out by Gleeble3800 at the austenite region from 850 to 1150℃and the adverse effects of Nb and B were analyzed by the fracture,microstructure and precipitate *** compression tests showed that the proportions of instable area in hot processing maps of 0.021%Nb and Nb-B steels were higher and the deformability of Nb free steel was *** tensile deformation experiments showed that the reduction areas of Nb free,0.021%Nb and Nb-B steels were 92%-99%,84%-98%and 67%-97%,*** addition of Nb or Nb and B inhibited the dynamic recrystallization during hot deformation,and consequently,more deformed grains were then formed in 0.021%Nb and Nb-B steels thus to obtain the microstructure with worse uniformity and then deteriorate the *** addition,the interaction between inclusions and microalloyed elements was also *** particles of 0.021%Nb and Nb-B steels dynamically precipitated during deformation and precipitated together with MnS thus to worsen the deformability,resulting in the decrease of reduction area.

关键词： Hot deformation Gear steel Processing map Dynamic recrystallization Microalloying

Study on a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding

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Advances in Manufacturing 2024年第2期12卷 288-299页

作者： Zhao-Qing Zhang Kai-ning Shi yao-yao Shi Yi-Hui Song Zhe he ya-Song Pu School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072People’s Republic of China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an710072People’s Republic of China

Profile grinding is the most crucial method for the ultra-precision machining of special-shaped ***,profile grinding produces a unique machining profile,and many random factors in the machining process lead to complex surface *** this study,the structural and probabilistic characteristics of the profile grinding of a special-shaped surface were analyzed,and a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding was *** forming process of a GH738 blade tenon tooth surface was considered as an example to demonstrate the *** comparison results showed that the simulation results had similar surface characteristics to the measurement results,and the relative error range of the 3D roughness parameter was 0.21%–19.76%,indicating an accurate prediction and characterization of the complex special-shaped surface under the action of multiple factors.

关键词： Special-shaped surface Profile grinding Surface morphology 3D characterization

Multi-Robot Cooperative Localization: Time-Varying Unobservable Subspace Analysis and Consistent Algorithm Design

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Journal of Systems Science & Complexity 2024年第5期37卷 1937-1955页

作者： HAO ning he Fenghua yaO Yu School of Astronautics Harbin Institute of Technology

This paper investigates the problem of cooperative localization(CL) for a multi-robot system(MRS) under dynamic measurement topology, which involves a group of robots collectively estimating their poses with respect to a common reference frame using ego-motion measurements and robot-to-robot relative measurements. The authors provide a theoretical analysis of the time-varying unobservable subspace and propose a consistent cooperative localization algorithm. First, the authors introduce the relative measurement graph(RMG) to represent the relative pose measurements obtained by the MRS at each instant. Then, the authors derive the local observability matrix over a time *** equivalent relationship is established between the local observability matrix and the spectral matrices of the RMG. Moreover, the authors present a method for constructing the unobservable subspace based on the RMG under different topology conditions. Based on this analysis, the authors design a consistent cooperative localization algorithm that satisfies the constraints of the time-varying unobservable subspace. An analytical optimal solution is derived for the constrained optimization *** Carlo numerical simulations are conducted to demonstrate the consistency and accuracy of the proposed method.

关键词： Consistency cooperative localization multi-robot system null space relative measurement graph time-varying unobservable subspace