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碱性介质中腐植酸电化学氧化动力学研究

现代化工 2025年第1期45卷 207-213页

作者：冯晴晴何德民范玉强关珺大连理工大学化工学院辽宁大连116024

采用三电极体系的H型隔膜电解池对腐植酸(humic acid,HA)在碱性条件下的电化学氧化过程进行动力学研究,考察了温度、阳极电位、碱液质量浓度对电化学氧化反应的影响。结果表明,HA电化学氧化符合二级反应动力学模型,活化能为19.94 kJ/mol... 详细信息

采用三电极体系的H型隔膜电解池对腐植酸(humic acid,HA)在碱性条件下的电化学氧化过程进行动力学研究,考察了温度、阳极电位、碱液质量浓度对电化学氧化反应的影响。结果表明,HA电化学氧化符合二级反应动力学模型,活化能为19.94 kJ/mol,各反应条件对HA进一步氧化成高附加值的煤酸(CA)有不同程度的影响。对各反应条件下的氧化过程进行分析发现,温度影响分子间键能和双电层充放电速率;阳极电位影响相应的电流密度,进而影响电子转移效率;碱液质量浓度改变溶液的电导性。HA电化学氧化后分子结构发生改变,可为进一步研究煤电化学氧化这一复杂反应提供参考。

关键词：腐植酸碱性电化学氧化动力学反应条件

Grinding force and surface quality in creep feed profile grinding of turbine blade root of nickel-based superalloy with microcrystalline alumina abrasive wheels

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Chinese Journal of Aeronautics 2021年第2期34卷 576-585页

作者： qing MIAO Wenfeng DING Weijie kuang Changyong YANG National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Creep feed profile grinding of the fir-tree blade root forms of single crystal nickel-based superalloy was conducted using microcrystalline alumina abrasive wheels in the present study. The grinding force and the surface quality in terms of surface topography, subsurface microstructure,microhardness and residual stress obtained under different grinding conditions were evaluated comparatively. Experimental results indicated that the grinding force was influenced significantly by the competing predominance between the grinding parameters and the cross-sectional root workpiece profile. In addition, the root workpiece surface, including the root peak and valley regions, was produced with the large difference in surface quality due to the nonuniform grinding loads along the root workpiece profile in normal section. Detailed results showed that the surface roughness, subsurface plastic deformation and work hardening level of the root valley region were higher by up to25%, 20% and 7% in average than those obtained in the root peak region, respectively, in the current investigation. Finally, the superior parameters were recommended in the creep feed profile grinding of the fir-tree blade root forms. This study is helpful to provide industry guidance to optimize the machining process for the high-valued parts with complicated profiles.

关键词： Creep feed profile grinding Fir-tree blade root Grinding force Single crystal nickel-based superalloy Surface quality

Bottomonium Spectrum with Screened Potential

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Communications in Theoretical Physics 2009年第10期52卷 653-661页

作者： LI Bai-qing CHAO kuang-Ta Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China Department of Physics Huzhou Teachers College Huzhou 313000 China

As a sister work of[Phys. Rev. D 79 （2009） 094004], we incorporate the color-screening effect due to light quark pair creation into the heavy quark-antiquark potential, and investigate the effects of screened potential on the spectrum of bottomonimn. We calculate the masses, electromagnetic decays, and E1 transitions of bottomonium states. We find that the fine splittings between χbJ （J = 0, 1, 2） states are in good agreement with experimental data, and the E1 transition rates of γ（2S） → γχbJ（1P） and γ（3S） →γχbJ（2P）（J = 0, 1, 2） all agree with data within experimental errors. In particular, the mass of γ（6S） is lowered down to match that of the γ（11020）, which is smaller than the predictions of the linear potential models by more than 100 MeV. Comparison between charmonium and bottomonium in some related problems is also discussed.

关键词： color-screening effect Bottomonium

Relationship between Coordination Structure and Biological Activity of Copper(II) Nicotinate

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1141-1147页

作者： CHEN qiang LI qing-Lu Institute of Animal Science and Technology Agricultural and Forestry University Fuzhou 350002 China Institute of Life Science Key Laboratory of Biological Pesticide and Chemicobiology of Education Ministry Agricultural and Forestry University Fuzhou 350002 China

The copper（Ⅱ） complexes of pyridine-3-carboxylic acid （nicotinic acid） and pyridine-2-carboxylic acid （isonicotinic acid） were synthesized, and their structures were characterized by elemental analysis, infrared spectrum, powder X-ray diffraction and so on. The results show that under experimental conditions, the ligands of synthesized copper nicotinate and copper isonicotinate are coordinated simultaneity with copper（Ⅱ） via the nitrogen of pyridine group and an oxygen of carboxylic acid group to form bidentate chelates. The crystal of copper nicotinate with two six-membered chelate rings belongs to monoclinic system, while that of copper isonicotinate having two five-membered chelate rings is of triclinic system. The tests show that the biological activities, such as the improvement of feed utilization, growth, anti-oxidation ability of organism and disease-resistant power, are different when copper nicotinate, copper inicotinate, copper-lysine chelate, copper-methionine chelate and copper sulphate are added in pig＇s feed, respectively. Due to its higher biological activity, less pollution and lower toxicity, copper nicotinate has wide potential applications as a feed additive.

关键词： pyridine-3-carboxylic acid (copper nicotinate) copper pyridine-2-carboxylic acid (copper isonicotinate) copper coordination structure toxicity growth-promoting enzyme activity

Phosphorus sorption capacities in a headstream landscape—The pond chain structure

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Journal of Environmental Sciences 2006年第5期18卷 1004-1011页

作者： FU qiang YIN Cheng-qing SHAN Bao-qing State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Understanding phosphorus sorption phenomena in different wetland sediments is important in controlling the P output in headstream watersheds. The pond chain structure （PCS） is widespread in the headstream agricultural watersheds in the southeast of China. Phosphorus sorption characteristics were determined for pond surface sediments （0-12 cm） along a pond chain structure in Liuchahe watershed of Chaohu Lake. Results showed that P sorption capacities （expressed by P sorption index （PSI）） varied both with the landscape position of the ponds and sediment depth. From foothill ponds to riverside ponds the P sorption capacities indicated a significant gradient variability. The higher elevation ponds showed greater sorption capacities, and with the pond elevation decline, P sorption capacities gradually decreased. Some physico-chemical properties, such as pH, oxalate-extractable Fe （Feox）, organic matter （TOC） and Mehlich l-extractable Ca, Mg of pond sediments also indicated significant gradient variability from high elevation ponds to low elevation ponds. Feox was the sediment parameters most highly positively correlated with PSI and was the key factor in controlling P sorption capacity in the pond chain structure （r=0.92, p〈0.001）. Long-term hydrologic and sediment inputs can affect the distribution of sediment constituents and further affect the P sorption capacity. Making the best of the spatial difference of sorption capacities of ponds in watersheds to control nonpoint source P pollutant is necessary.

关键词： pond sediment adsorption spatial variability nonpoint source

The holographic fermions dual to massive gravity

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Science China(Physics,Mechanics & Astronomy) 2016年第10期59卷 49-57页

作者： Li-qing Fang[[ Xiao-Mei kuang Jian-Pin Wu School of Physics and Electronic Information Shangrao Normal UniversityShangrao 334000China Department of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of High Temperature Superconductors Shanghai 200444China Instituto de Fisica Pontificia Universidad Catolica de ValparaisoCasilla 4059ValparaisoChile Institute of Gravitation and Cosmology Department of PhysicsSchool of Mathematics and PhysicsBohai UniversityJinzhou 121013China

We investigate the properties of the spectral function of the fermionic operator in the field theory which is dual to a 4-dimensional massive gravity. We first study the Fermi surface and the dispersion relation in the dual boundary theory. We find that as the massive parameters is decreased, the Fermi momentum becomes lower and the low energy excitation near Fermi surface behaves more like non-Fermi liquid. Then, we introduce a dipole coupling in the bulk theory and explore the emergence of a gap in the fermionic spectral function. It is found that larger critical dipole coupling is needed to open the gap than that in Einstein gravity. Accordingly,in the field theory dual to massive gravity, it requires stronger negative dipole coupling to generate the marginal Fermi liquid.

关键词： holography duality AdS/CFT correspondence holographic fermions

Layered-stacking of titania films for solar energy conversion:Toward tailored optical,electronic and photovoltaic performance

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Journal of Energy Chemistry 2018年第3期27卷 690-702页

作者： Wu-qiang Wu Jin-Feng Liao Dai-Bin kuang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-sen University.Guangzhou 510275Guangdong.China

Nanostructured TiO2 with differentiate morphologies has attracted tremendous attention due to its wide band-gap nature as well as outstanding optical and electric properties for solar-driven light-toelectricity conversion application. Layered-stacking TiO2 film such as double-layer, tri-layer, quadrupleor quintuplicate-layer, is highly desirable to the design of high-performance semiconductor material photoanodes and the development of advanced photovoltaic devices. In this minireview, we will summarize the recent progress and achievements on proof-of-concept of layered-stacking TiO2 films（LTFs） for solar cells with emphasis on the tailored properties and synergistic functionalization of LTFs, such as optimized sensitizer adsorption, broadened light confinement as well as facilitated electron transport *** demonstrations of LTFs photovoltaic systems provide lots of possibilities and flexibilities for more efficient solar energy utilization that a wide variety of TiO2 with distinguished morphologies can be integrated into differently structured photoanodes with synergistic and complementary advantages. This key structure engineering technology will also pave the way for the development of next generation state-ofthe-art electronics and optoelectronics. Finally, from our point of view, we conclude the future research interest and efforts for constructing more efficient LTFs as photoelectrode, which will be highly warranted to advance the solar energy conversion process.

关键词： TiO2 Charge transport Light scattering Power conversion efficiency Solar cells

Planar anisotropy of commercially pure titanium sheets

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Rare Metals 2013年第1期32卷 1-4页

作者： qing-Dong Zhang qiang Cao School of Mechanical Engineering University of Science and Technology Beijing

Commercially pure titanium （CP Ti） sheets show typical planar anisotropy due to the inherently crys- tallographic texture and manufacturing process. To char- acterize the planar anisotropic behaviors of CP Ti sheets in the forming process, uniaxial tensile tests of TA0 sheets were performed along rolling, transverse, and diagonal directions at room temperature; corresponding stress-strain curves and Lankford coefficients were obtained. Based on Hi11＇48 and Barlat＇89 yield functions, the planar anisotropy of TA0 sheets was investigated. In order to verify the accuracy of two models, we compared the experimental and predicted values of yield stress and Lankford coeffi- cients. It reveals that Barlat＇89 criterion with M = 10 is good agreement with experimental data, and the obtained function can be used in simulation of forming process.

关键词： Commercially pure titanium Planaranisotropy Yield criterion Barlat'89 model

Weldability of 1000 MPa Grade Ultra-low Carbon Bainitic Steel

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Journal of Iron and Steel Research International 2016年第7期23卷 705-710页

作者： qing-mei JIANG Xiao-qiang ZHANG Li-qing CHEN Pipeline Department of China Petroleum Pipeline Engineering Corporation Langfang 065000 Hebei China State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 Liaoning China

Maximum hardness test in weld heat-affected zone（HAZ）,oblique Y-groove cracking test and mechanical property test of welding joint of 1 000 MPa grade ultra-low carbon bainitic steel were carried out,so as to research the weldability of the *** results show that the steel has lower cold cracking sensitivity,and preheating temperature of 100 ℃ can help completely eliminate cold cracks,generating good process *** increase of preheating temperature can reduce the hardening degree of heat-affected *** strength of welding joint decreases and hardness reduces when heat inputs increase,and excellent mechanical properties can be obtained when low welding heat inputs are *** lath bainites of different orientations combined with a few granular bainites that effectively split the original coarse austenite grains are the foundation of good properties.

关键词： ultra-low carbon bainitic steel weldability cold cracking microstructure mechanical property