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Journal of Arid Land 2013年第3期5卷 408-414页

作者： YaMing DONG chaoCheng ZHAO yun cai DongFeng ZHAO College of Chemistry and Chemical Engineering China University of Petroleum Xinjiang Department of Environmental Protection

This paper discussed the optimization of conditions for remediation of crude oil-polluted soil based on pot experiment by applying reed-specific degrading bacteria, and using response surfaces methodology. We took the initial crude oil concentration, the amount of inoculation, the ratio of nitrogen and phosphorus, and the use of surfactant （Tween-80） as independent variables （factors）, and the degrading ratio of crude oil as the dependent variable （response） after a 90-day experiment. The experiment explored the impacts of each independent variable and their interactions on the bioremediation of crude oil-polluted soil using the Box-Behnken design. Working with a simulated forecasting model the study obtained optimization va reed＋specific degrading bacteria, a nitrogen to phosphorus ues for the treatment parameters of 200 g/kg of the ratio of about 6.0. and 0.2% surfactant. Under experimental conditions, for crude oil concentrations of 10, 30 and 50 g/kg, the optimal effects of the treatments achieved 71.87%, 66.61% and 54.52% degradation of the crude oil, respectively. The results can provide a basis for the technical development of plant-microorganism combined bioremediation of crude oil-polluted soil.

关键词： crude oil pollution plant-microorganism response surfaces soil remediation

Relationship between light and heavy fractions of organic matter for several agricultural soils in China

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Journal of Environmental Sciences 2005年第6期17卷 917-920页

作者： YIN yun-feng cai Zu-cong LU Jia-long State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China College of Geographical Sciences Fujian Normal University Fuzhou 350007 China College of Resourcesand Environment Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 China

Although numerous studies about the nature and turnover of soil organic matter（SOM） in light and heavy fractions（ LFOM and HFQM, respectively） have been made, little information is available in relation to the relationship between LFQM and HFOM, and no attempts have been made to quantify a general relationship between LFQM and HFQM for agricultural soils under field condition. Qur hypothesis is there may be an inherent relationship between LFQM and HFQM for agricultural soils under certain unaltered management practices for a long period, to this end, we therefore studied typically soils taken from different parts in China by using a simple density fractionation procedure. The results indicated that LFQM was positively correlated with LFOM/HFOM ratio for three typical soils. This information will be of particular use not only in deepening our understanding of the dynamics of SQM fractions but also in evaluating the potential of agricultural soils to sequestrate C under different management practices in a long term.

关键词： soil organic matter light fraction heavy fraction agricultural soils

Effect of tempering temperature on strain hardening exponent and flow stress curve of 1000MPa grade steel for construction machinery

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Journal of Iron and Steel Research International 2017年第9期24卷 950-956页

作者： Yang yun Qing-wu cai Bao-sheng Xie Shuang Li National Engineering Research Center of Advanced Rolling University of Science and Technology BeijingBeijing 100083China Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China

To study the effect of tempering temperature on strain hardening exponent and flow stress curve,one kind of 1000 MPa grade low carbon bainitic steel for construction machinery was designed,and the standard uniaxial tensile tests were conducted at room temperature.A new flow stress model,which could predict the flow behavior of the tested steels at different tempering temperatures more efficiently,was *** relationship between mobile dislocation density and strain hardening exponent was discussed based on the dislocation-stress *** equation and an inverse proportional function were adopted to describe the mobile dislocation,and two mathematical models were established to describe the relationship between tempering temperature and strain hardening *** regression analysis was applied to the Arrhenius type model,hence,the activation energy was determined to be 37.6kJ/***,the square of correlation coefficient was 0.985,which indicated a high reliability between the fitted curve and experimental *** comparison with the Arrhenius type curve,the general trend of the inverse proportional fitting curve was coincided with the experimental data points except of some fitting ***,the Arrhenius type model can be adopted to predict the strain hardening exponent at different tempering temperatures.

关键词： Tempering temperature Flow stress curve Strain hardening exponent Microscopic mechanism Mathematical model

Synthesis and anti-inflammatory activity of gold-nanoparticle bearing a dermatan sulfate disaccharide analog

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Chinese Chemical Letters 2018年第1期29卷 81-83页

作者： Chengxiang Shang chao cai Cuixia Zhao Yuguo Du State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences School of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Key Lab of Marine Drugs Ministry of Education of China School of Medicine and Pharmacy Ocean University of China

A dermatan sulfate （DS） repeating disaccharide analog, β-L-idopyranosiduronate-（1→3）-2-amino-2- deoxy-4,6-di-O-sulfo-β-D-galactopyranoside, has been convergently synthesized and successfully applied to prepare the GAG-functionalized gold glyconanoparticle. This new material exhibited good anti-inflammatory activity which was comparable to that of the drug ibuprofen incarrageenan-induced paw edema in a rat model.

关键词： L-lduronic acidGold glyconanoparticlesDermatan sulfate disaccharideAnti-inflammatoryCarbohydrates

More than softer-when-brighter: The X-ray powerlaw spectral variability in NGC 4051

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Science China(Physics,Mechanics & Astronomy) 2020年第12期63卷 102-112页

作者： yun-Jing Wu Jun-Xian Wang Zhen-Yi cai Jia-Lai Kang Teng Liu Zheng cai CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Department of Astronomy Tsinghua UniversityBeijing 100084China Max-Planck-Institut für Extraterrestrische Physik Garching bei Munchen D-85748Germany

The powerlaw X-ray spectra of active galactic nuclei at moderate to high accretion rates normally appear softer when they brighten,for which the underlying mechanisms are yet *** XMM-Newton observations and excluding photons<2 keV to avoid contamination from the soft excess,in this work we scrutinize the powerlaw spectral variability of NCG 4051 from two new *** first find that a best-fit"softer-when-brighter"relation is statistically insufficient to explain the observed spectral variabilities,and intervals deviated from the empirical relation are clearly visible in the light curve of 2-4 ke V/4-10 keV count rate *** deviations are seen not only between but also within individual XMM-Newton exposures,consistent with random variations of the corona geometry or inner structure(with timescales as short as^1 ks),in addition to those behind the smooth"softer-when-brighter"*** further find the"softer-when-brighter"trend gradually weakens with the decreasing timescale(from^100 ks down to 0.5 ks).These findings indicate that the powerlaw spectral slope is not solely determined by its *** propose a two-tier geometry,including flares/nano-flares on top of the inner disc and an embedding extended corona(heated by the flares,in analogy to solar corona)to explain the observations together with other observational clues in *** spectral variabilities could be due to individual flares/nano-flares,while slow ones are driven by the variations in the global activity of inner disc region(akin to the variation of solar activity,but not the accretion rate)accompanied with heating/cooling and inflation/contraction of the extended corona.

关键词： active galaxies X-ray Seyfert galaxies

Microstructure and Optical Properties of Ti_(54.5)Ni_(45.5) Nanocrystalline Thin Film

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Acta Metallurgica Sinica(English Letters) 2017年第12期30卷 1231-1235页

作者： Xin Zhang Jie-He Sui Yong-chao Lei Wei cai School of Materials Science and Engineering Tianjin University of Technology National Key Laboratory Precision Hot Processing of Metals Harbin Institute of Technology

Nanocrystalline Ti54.5Ni45.5 thin film was prepared by magnetron sputtering followed by rapid thermal annealing. The film displayed martensite structure and （001） compound twin substructure, and the transformation temperatures Ms and As are 313 and 365 K, respectively. The reflectivity for the wavelength from 200 to 800 nm at 298 and 393 K was investigated, and the results showed that the optical reflectivity contrast between martensite and austensite at 780, 650, 514 and 405 nm was 105.64, 170.83, 112.22 and 149.92%, respectively, which were larger than those of other reported optical recording materials.

关键词： Ti–Ni thin films Sputtering Shape memory alloys Optical properties Microstructure

Effect of noble metal nanoparticle size on C–N bond cleavage performance in hydrodenitrogenation: a study of active sites

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Frontiers of Chemical Science and Engineering 2023年第12期17卷 1986-2000页

作者： Yi-Fan Xue Jie Feng yun-cai Song Wen-Ying Li State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024China

Breakage of the C-N bond is a structure sensitive process,and the catalyst size significantly affects its *** the active metal nanoparticle scale,the role of catalyst size in C-N bond cleavage has not been clearly ***,Ru catalysts with variable nanoparticle sizes were obtained by modulating the reduction temperature,and the catalytic activity was evaluated using 1,2,3,4-tetrahydroquinoline and o-propylaniline with different C-N bond hybridization patterns as *** showed a 13 times higher reaction rate for sp3-hybridized C-N bond cleavage than sp2-hybridized C-N bond cleavage,while the reaction rate tended to increase first and then decrease as the catalyst nanoparticle size *** concentrations of terrace,step,and corner sites were found in different sizes of Ru *** relationship between catalytic site variation and C-N bond cleavage activity was further investigated by calculating the turnover frequency values for each *** analysis indicates that the variation of different sites on the catalyst is the intrinsic factor of the size dependence of C-N bond cleavage activity,and the step atoms are the active sites for the C-N bond *** Ru nanoparticles are smaller than 1.9 nm,they have a strong adsorption effect on the reactants,which will affect the catalytic performance of the Ru ***,these findings were also confirmed on other metallic Pd/Pt *** role of step sites in C-N bond cleavage was proposed using the density function theory *** reactants have stronger adsorption energies on the step atoms,and step atoms have d-band center nearer to the Fermi *** this case,the interaction with the reactant is stronger,which is beneficial for activating the C-N bond of the reactant.

关键词： sp3 sp2-hybridized C–N bond noble metal nanoparticle catalytic active site turnover frequency DFT

Hierarchical Porous Polymer Beads Prepared by Polymerization-induced Phase Separation and Emulsion-template in a Microfluidic Device

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Chinese Journal of Polymer Science 2014年第12期32卷 1646-1654页

作者： Wei-cai Wang Yan-xiong Pan Kai Shi chao Peng 姬相玲 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Porous polymer beads（PPBs） containing hierarchical bimodal pore structure with gigapores and meso-macropores were prepared by polymerization-induced phase separation（PIPS） and emulsion-template technique in a glass capillary microfluidic device（GCMD）. Fabrication procedure involved the preparation of water-in-oil emulsion by emulsifying aqueous solution into the monomer solution that contains porogen. The emulsion was added into the GCMD to fabricate the（water-in-oil）-in-water double emulsion droplets. The flow rate of the carrier continuous phase strongly influenced the formation mechanism and size of droplets. Formation mechanism transformed from dripping to jetting and size of droplets decreased from 550 μm to 250 μm with the increase in flow rate of the carrier continuous phase. The prepared droplets were initiated for polymerization by on-line UV-irradiation to form PPBs. The meso-macropores in these beads were generated by PIPS because of the presence of porogen and gigapores obtained from the emulsion-template. The pore morphology and pore size distribution of the PPBs were investigated extensively by scanning electron microscopy and mercury intrusion porosimetry（MIP）. New pore morphology was formed at the edge of the beads different from traditional theory because of different osmolarities between the water phase of the emulsion and the carrier continuous phase. The morphology and proportion of bimodal pore structure can be tuned by changing the kind and amount of porogen.

关键词： Porous polymer beads Hierarchical Polymerization-induced phase separation Emulsion-template Microfluidic device.

Propagation of dark soliton interacting with domain wall in two immiscible Bose–Einstein condensates

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Chinese Physics B 2019年第11期28卷 295-303页

作者： Lang Zheng Yi-cai Zhang chao-Fei Liu Jiangxi Provincial Education Examination Authority Nanchang 330038China School of Science Jiangxi University of Science and TechnologyGanzhou 341000China School of Physics and Electronic Engineering Guangzhou UniversityGuangzhou 510006China

Reflection and transmission are two behaviors of wave propagating to an interface. The immiscible binary mixtures of Bose–Einstein condensates can form the symmetry-breaking state, in which the domain wall on the center can serve as the interface. In this study, we explore in detail the propagation of a dark soliton interacting with the domain wall in the harmonic trap. We find that the low-energy dark soliton is easy to form the transmission and the high-energy dark soliton trends to reflect from the domain wall. Both reflection and transmission of dark soliton on the domain wall induce the sound radiation. But the sound radiation in the reflection derives from the collective oscillation of condensates, and it in the transmission comes not only from the collective oscillation, but also from the condensate filling in the dark soliton.

关键词： Bose–Einstein condensate dark soliton

Pore-scale water-gas distribution and gas permeability of natural gas hydrate reservoirs in the South China Sea

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Geoscience Frontiers 2024年第4期15卷 315-329页

作者： Yuxuan Xia Derek Elsworth Jianchao cai Cheng Lu chao Ma National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing 102249China Department of Energy and Mineral Engineering G3 Center and Energy InstituteThe Pennsylvania State UniversityUniversity Park 16802PAUnited States Guangzhou Marine Geological Survey China Geological SurveyGuangzhou 510075China Center of Oil&Natural Gas Resource Exploration China Geological SurveyBeijing 100083China

Challenges in water drainage within natural gas hydrate reservoirs in the Shenhu area of the South China Sea,characterized by high clay content and strong hydrophilicity,significantly hinder natural gas *** the effects of gas pressure and liquid/gas saturation on gas permeability reveals essential insights for increasing gas production *** report gas displacement experiments on clayey-silt sediment samples,alongside X-ray computed tomography imaging,that reveal critical findings:a notable increase in flow rate and permeability as displacement pressure nears compaction pressure,highlighting the role of pressure management in enhancing recovery;water displacement from varying pore sizes under different pressures,highlighting the influence of pore size on fluid dynamics,and structural changes,including microfracture formation and a significant fracture that enlarges total pore space by about 15%,which collectively suggest methods to improve gas flow and ***,our analysis identifies average throat length,fractal dimension,and succolarity as principal controls on gas permeability,indicating the substantial impact of microstructural properties on extraction *** outcomes offer valuable strategies for optimizing natural gas hydrate reservoir development in the South China Sea,emphasizing the need for meticulous pressure and saturation control and in applying a deep understanding of microstructural dynamics.

关键词： Natural gas hydrate Clayey-silt sediments Gas saturation Gas permeability Microstructure