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Characteristics of AOT Microemulsion Structure: a Small Angle X-ray Scattering Study

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Chinese Chemical Letters 2001年第11期12卷 1023-1026页

作者： Jun cheng LIU Gan Zuo LI bu Xing HAN Key lab for colloid and interface chemistry of State Education Ministry Shandong UniversityJinan 250100 Center for Molecular Science Institute of ChemistryChinese Academy of ScienceBeijing 100080

The method of synchrotron radiation small-angle X-ray scattering (SR-SAXS) has been used to obtain structural information on the system of bis (2-ethylhexyl) sulfosuccinate (AOT)/H2O/isooctane. By using the Guinier plot (Ln I (q) versus q(2)) on the data sets in a defined small q range (0.03-0.06 Angstrom (-1)), the gyration radius at different water/surfactant molar ratio, W-0, was obtained. With the increase of W-0, the gyration radius (R-g) increased at the range of 23.2 similar to 52.7 Angstrom.

关键词： bis(2-ethylhexyl)suffosuccinate(AOT) microemulsion gyration radius small angle X-ray scattering

Effect of rolling technologies on the properties of Pb?0.06wt%Ca?1.2wt%Sn alloy anodes during copper electrowinning

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International Journal of Minerals,Metallurgy and Materials 2015年第11期22卷 1205-1211页

作者： Jian Yang bu-ming Chen Hui Hang Zhong-cheng Guo Shuai Wang Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Kunming Hendera Science and Technology Co. Ltd.

The objective of this work was to study the effect of different rolling technologies on the properties of Pb-0.06wt%Ca-1.2wt%Sn anodes during copper electrowinning and to determine the relationship between the properties of the anodes and rolling techniques during copper electrowinning. The anode process was investigated via anodic polarization curves, cyclic voltammetry curves, electrochemical impedance spectra, and corrosion tests. The microscopic morphology and phase composition of the anodic oxide layers were observed by scanning electron microscopy and X-ray diffraction, respectively. Observable variations in the electrocatalytic activity and reaction kinetics of anodes during electrowinning indicated that the electrochemical behavior of the anodes was strongly affected by the rolling technology. An increase in the rolling number tended to decrease the oxygen evolution overpotential and the corrosion rate of the anodes. These trends are contrary to that of the apparent exchange current density. Furthermore, the intensities of diffraction peaks associated with PbO, PbOx, and α-PbO2 tended to increase with increasing rolling number. In addition, the rolled anodes exhibited a more uniform microstructure. Compared with one-way rolled anodes, the eight-time cross rolled anodes exhibited better electrocatalytic activity and improved corrosion resistance.

关键词： anode materials lead calcium tin alloys rolling electrocatalysis corrosion rate electrowinning

Theoretical Study on the Dark Oxidation Reaction Mechanism of Ethers

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1402-1408页

作者： WANG Gui-Xiu ZHU Rong-Xiu ZHANG Dong-Ju LIU cheng-bu School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China

The dark oxidation reactions of ethers including aether, isopropyl ether, phenyl isopropyl ether, and benzyl isopropyl ether have been studied by using density functional theory calculations. The structures of initial Contact charge transfer complexes （CCTCs）, transition states and caged radical intermediates have been located at the B3LYP/6-31G （d） level, The bonding nature of ethers with triplet 02 in CCTCs has been analyzed, and the detailed mechanism of dark oxidation reactions of ether is presented clearly.

关键词： ethers dark oxidation contact charge transfer complex reaction mechanism DFT

Extraction of niobium, yttrium, and cerium from a low-grade niobium-bearing ore by roasting(NH_4)_2SO_4-Na_2SO_4-H_2SO_4 system

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Rare Metals 2014年第6期33卷 754-760页

作者： wen-cheng Gao Jian-Kang wen Biao Wu He Shang National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous Metals

A novel process of extracting niobium, yttrium,and cerium from a low-grade niobium-bearing ore by the roasting（NH4）2SO4-Na2SO4-H2SO4 system was experimentally studied. The influences of various factors,such as roasting temperature, roasting time, mass ratio of agents-to-ore and particle size fraction on the extraction of valuable metals were comprehensively investigated. It is found that the roasting Na2SO4-H2SO4 system is effective to extract the niobium, yttrium, and cerium. The obtained optimum conditions for the extraction of Nb, Y, and Ce are roasting temperature of 300 °C, roasting time of 3 h, mass ratio of Na2SO4：H2SO4：Ore of 0.5：1.0：1.0, and particle size fraction of-74 lm（~95 %）. Under the optimum condition, the maximum recovery of Nb, Y, and Ce can reach90.53 %, 92.15 %, and 98.04 %, respectively. All the results generated from this study will provide the fundamentals for Nb, Y, and Ce extraction from a niobiumbearing ore with low-grade.

关键词： Extraction Niobium Yttrium Cerium Lowgrade

Characteristics and Culture Conditions of a Bioflocculant Produced by Penicillium sp.

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Biomedical and Environmental Sciences 2010年第3期23卷 213-218页

作者： LI-FAN LIU wen cheng Faculty of Civil and Transportation Engineering Guangdong University of Technology Guangzhou 510006 Guangdong China Chemistry & Environment South China Normal University Guangzhou 510631 Guangdong China

Objective To study the characteristics of a bioflocculant named MBF7 produced by Penicillum strain HHE-P7 and the effects of cultivation conditions on bioflocculant production. Methods The chemical group in the bioflocculant molecules was shown by Fourier transform infrared （FTIR） spectra, and the average molecular weight of MBF7 was estimated by gel permeation chromatography. The effects of medium components on bioflocculant production and flocculating activity were studied. Results Phospho-, amino-, hydroxyl, and carboxyl groups were the major fractions of MBF7, and the molecule weight was about 3.0 × 10^5 Da. In addition, the carbon and nitrogen sources favorable for the bioflocculant production were glucose and yeast extract respectively. When the initial pH of the medium was adjusted to 5.0, high flocculant efficiency could be achieved. Conclusion The bioflocculant MBF7 is a new macromolecule with high flocculating efficiency for Kaolin suspension, and could be produced under appropriate culture conditions.

关键词： Bioflocculant Penicillium sp. Flocculating activity Carbon and nitrogen sources

Molecular mechanism of immune response induced by foreign plasmid DNA after oral administration in mice

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World Journal of Gastroenterology 2007年第28期13卷 3847-3854页

作者： Jian-wen Liu Jun cheng Institute of Infectious Diseases Beijing Ditan Hospital Beijing 100011 China School of Food Science & Technology Southern Yangtze University Wuxi 214036 Jiangsu Province China

AIM： TO study immune response induced by foreign plasmid DNA after oral administration in mice.METHODS： Mice were orally administered with 200 μg of plasmid pcDNA3 once and spleen was isolated 4 h and 18 h after administration. Total RNA was extracted from spleen and gene expression profile of BALB/c mice spleen was analyzed by using Affyrnetrix oligonucleotide GeneChip. Functional cluster analysis was conducted by GenNAPP software.RESULTS： At 4 h and 18 h after oral plasmid pcDNA3 administration, a number of immune-related genes, including cytokine and cytokine receptors, chemokines and chemokine receptor, complement molecule, proteasome, histocompatibility molecule, lymphocyte antigen complex and apoptotic genes, were upregulated. Mloreover, MAPPFinder results also showed that numerous immune response processes were upregulated. In contrast, the immunoglobulin genes were down-regulated.CONCLUSION： Foreign plasmid DNA can modulate the genes expression related to immune system via the gastrointestinal tract, and further analysis of the related immune process may help understand the molecular mechanisms of immune response induced by foreign plasmid via the gastrointestinal tract.

关键词： Foreign plasmid Microarray Immune system Gastrointestinal tract Gene expression

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie Liu Changqing Xu Da-Jian Wu Ying cheng Xiao-Jun Liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： Yan Zhao Qiang Yuan Liting Yang Guisheng Liang Yifeng cheng Limin Wu Chunfu Lin Renchao Che College of Physics Donghua UniversityShanghai 201620People’s Republic of China School of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization

Spontaneous Orientation Polarization of Anisotropic Equivalent Dipoles Harnessed by Entropy Engineering for Ultra‑Thin Electromagnetic Wave Absorber

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Nano-Micro Letters 2025年第1期17卷 424-438页

作者： Honghan Wang Xinyu Xiao Shangru Zhai Chuang Xue Guangping Zheng Deqing Zhang Renchao Che Junye cheng Liaoning Key Lab of Lignocellulose Chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefinerySchool of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034People’s Republic of China School of Life Science and Biotechnology Dalian University of TechnologyDalian 116024People’s Republic of China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Department of Materials Science Shenzhen MSU-BIT UniversityShenzhen 517182People’s Republic of China

The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engineering of conductive/dielectric *** migration modes within HEAs as manipulated by the electronegativity,valence electron configurations and molar proportions of constituent elements determine the steady state and efficiency of equivalent ***,enlightened by skin-like effect,a reformative carbothermal shock method using carbonized cellulose paper(CCP)as carbon supporter is used to preserve the oxygencontaining functional groups(O·)of carbonized cellulose fibers(CCF).Nucleation of HEAs and construction of emblematic shell-core CCF/HEAs heterointerfaces are inextricably linked to carbon metabolism induced by O·.Meanwhile,the electron migration mode of switchable electronrich sites promotes the orientation polarization of anisotropic equivalent *** virtue of the reinforcement strategy,CCP/HEAs composite prepared by 35%molar ratio of Mn element(CCP/HEAs-Mn_(2.15))achieves efficient electromagnetic wave(EMW)absorption of−51.35 dB at an ultra-thin thickness of 1.03 *** mechanisms of the resulting dielectric properties of HEAs-based EMW absorbing materials are elucidated by combining theoretical calculations with experimental characterizations,which provide theoretical bases and feasible strategies for the simulation and practical application of electromagnetic functional devices(e.g.,ultra-wideband bandpass filter).

关键词： High-entropy alloys Carbothermal shock Switchable electron migration modes Emblematic shell-core heterointerfaces Ultra-thin thickness