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growth of covellite crystal onto azurite surface during sulfurization and its response to flotation behavior

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International Journal of Mining Science and Technology 2021年第6期31卷 1003-1012页

作者： Jinpeng Cai Peilun Shen Dianwen Liu Xiaolin Zhang Jianjun Fang Chao Su Xingcai Yu Jiangli Li Han Wang State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resources EngineeringKunming University of Science and TechnologyKunming 650093China

In this work,the growth of copper sulfide crystal onto azurite surfaces during sulfurization and its response to flotation are *** emission scanning electron microscopy-energy dispersive X-ray spectroscopy(FESEM) and X-ray diffraction(XRD) studies confirmed that the sulfurization of azurite is not limited to the mineral surface,but rather penetrates into the bulk to form covellite crystal(synCuS),creating favorable conditions for the stable adsorption of xanthate and greatly promoting the azurite ***,as demonstrated by X-ray photoelectron spectroscopy(XPS) and time of flight secondary ion mass spectrometry(TOF-SIMS) analyses,a redox reaction occurred during this process,and Cu(Ⅱ) onto the mineral surface was reduced to Cu(Ⅰ).Correspondingly,reduced S^(2-) was oxidized to(S_(2))^(2-),(S_n)^(-2),and even to deeper oxidation state S~0,(S_(x)O_(y))^(n-) and SO_(4)^(2-).Excess sodium sulfide strengthens copper sulfide to form onto the azurite surface,and provides enough raw material for crystal copper sulfide to grow,resulting in the formation of "flake-like" covellite with a better ***,the floatability of azurite decreased dramatically under this condition,because the generated massive colloidal copper sulfide in flotation pulp deteriorates the flotation environment,resulting in a decreased effective adsorption of collector onto azurite surfaces.

关键词： Azurite Sulfurization floatation Covellite crystal growth Colloid

growth and aggregation micromorphology of natural gas hydrate particles near gas-liquid interface under stirring condition

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Chinese Journal of Chemical Engineering 2021年第12期34卷 65-77页

作者： Qihui Hu Xiaoyu Wang Wuchang Wang Yuxing Li Shuai Liu Shandong Key Laboratory of Oil-Gas Storage and Transportation Safety College of Pipeline and Civil EngineeringChina University of PetroleumQingdao 266580China State Key Laboratory of Natural Gas Hydrates Beijing 100028China Research Institute of Experiment and Detection Petro China Xinjiang Oilfield CompanyKaramay 834000China

To investigate the morphological evolution of the whole growth and aggregation processes of hydrate crystals near the gas–liquid interface,we used a high-pressure visual reactor with high-speed camera to capture the micromorphology of hydrate particles in a natural gas+pure water system with pressure from 2.6 to 3.6 MPa and sub-cooling from 4.7 to 6.23*** results showed that under low sub-cooling conditions,the amount and size of particles increased first and then decreased in the range of 0–330 lm,and the small particles always *** particles can be roughly classified into two categories:planar flake particles and polyhedral solid ***,the concept of maximum growth dominant particle size was proposed to distinguish the morphological boundary of growth and *** addition,the micro model was established to better reflect the effects of particle formation process and evolution mechanism near the gas–liquid interface under stirring *** results of this study can provide a guidance for flow assurance in multiphase pipeline.

关键词： Natural gas hydrate growth Aggregation Gas-liquid interface Micromorphology Physical model

growth and Electronic Properties of Ag Nanoparticles on Reduced CeO2-x（111） Films

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Chinese Journal of Chemical Physics 2012年第6期25卷 713-718,I0004页

作者： Dan-dan Kong Yong-he Pan Guo-dong Wang Hai-bin Pan Jun-fa Zhu National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei230029 China

Ag nanoparticles grown on reduced CeO2-x thin films have been studied by X-ray plhotoelec- tron spectroscopy and resonant photoelectron spectroscopy of the valence band to understand the effect of oxygen vacancies in the CeO2-x thin films on the growth and interracial elec- tronic properties of Ag. Ag grows as three-dimensional particles on the CeO2-x （111） surface at 300 K. Compared to the fully oxidized ceria substrate surface, Ag favors the growth of smaller particles with a larger particle density on the reduced ceria substrate surface, which can be attributed to the nucleation of Ag on oxygen vacancies. The binding energy of Ag3d increases when the Ag particle size decreases, which is mainly attributed to the final-state screening. The interracial interaction between Ag and CeO2_x（lll） is weak. The resonant enhancement of the 4f level of Ce3＋ species in RPES indicates a partial Ce4＋--＋Ce3＋ reduction after Ag deposited on reduced ceria surface. The sintering temperature of Ag on CeO 1.85 （111） surface during annealing is a little higher than that of Ag on CeO2 （111） surface, indicating that Ag nanoparticles are more stable on the reduced ceria surface.

关键词： Silver Ceria growth Electronic structure X-ray photoelectron spectroscopy Resonant photoelectron spectroscopy

growth structures and growth strata of the Qianjiadian Basin in the western Yanshan fold and thrust belt, North China

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Science China Earth Sciences 2019年第7期62卷 1092-1109页

作者： Xiaofei SHI Shaofeng LIU Chengfa LIN State Key Laboratory of Geological Processes and Mineral Resources and School of Geosciences and Resources China University of Geosciences (Beijing)

The northwestward subduction of the Izanagi Plate beneath the eastern Eurasian Plate during the Late Mesozoic caused a series of compressional deformation events in the Yanshan fold and thrust belt(YFTB), but the tectonic deformation timing, tectonic properties and relationship between tectonic uplift and sediment accumulation in the intermontane basins continue to be debated. For this reason, the sedimentology, sediment provenance, and basin structure of the Qianjiadian Basin(QJB) in the northern Beijing region during the Late Jurassic and Early Cretaceous were studied in detail. The results suggest that a fault-propagation fold-type(FPFT) growth structure and growth strata developed on the western edge of the QJB and that the top part of Member 2 and Member 3 of the Tuchengzi Formation are growth strata controlled by the limb rotation mechanism. In two small thrust faults in the QJB, the Mesoproterozoic Xiamaling Formation is thrust over the Tuchengzi Formation, and these faults may have controlled the development of the fault-bend fold-type growth strata. An analysis of the "source-to-sink" process suggests that the hanging wall succession of the Shangyi-Pingquan fault(SPF) was the main source area of the Late Jurassic to early Early Cretaceous strata in the QJB. A zircon206 Pb/238 U age of 140.8±2.4 Ma for the volcanic rocks at the bottom of the FPFT growth strata represents the timing of the initiation of FPFT growth structure development. The discovery of the FPFT growth structure and growth strata in the QJB indicate that the QJB was an intermontane flexural basin controlled by fold and thrust structures during the early Early Cretaceous. Near the E-W-trending SPF, the NE-SW-trending Qianjiadian thrust fault(QJTF) and two small intrabasinal thrust faults may constitute a unified right-lateral strike-slip system that formed in response to the northwestward flat subduction of the Izanagi Plate beneath the East Asian continent during the Jurassic-Early Cretaceou

关键词： Yanshan fold and thrust belt Qianjiadian Basin Tuchengzi Formation growth structure growth strata Izanagi Plate

growth and alkaline phosphatase activity of Chattonella marina and Heterosigma akashiwo in response to phosphorus limitation

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Journal of Environmental Sciences 2015年第2期27卷 1-7页

作者： Zhao-Hui Wang Yu Liang College of Life Science and Technology Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education InstitutesJinan University

The growth and alkaline phosphatase activity（APA） of two raphidophyceae species Chattonella marina and Heterosigma akashiwo were investigated in response to P-limitation and subsequent addition of dissolved inorganic phosphorus（DIP, Na H2PO4） and two dissolved organic phosphorus（DOP） compounds： guanosine 5-monophosphate（GMP） and triethyl phosphate（TEP）. APA levels increased greatly after P-starvation as the decrease of the cellular phosphorus quotes（Qp）. C. marina responded to P-limitation quickly and strongly, with 10-fold increase in APA within 24 hr after P-starvation. The larger difference between maximal and minimal QP values in C. marina indicated its high capacity in P storage. APA of H. akashiwo was maximally enlarged about 2.5 times at 48 hr of P-starvation. After the addition of nutrients, cell numbers of C. marina increased in all treatments including the P-free culture, demonstrating the higher endurance of C. marina to P-limitation. However, those of H. akashiwo increased only in DIP and GMP cultures. APA increased only after the addition of the monophosphate ester GMP. The results suggest that quick responses of C. marina to P-limitation, high capacity in P storage as well as endurance for P-depletion provide this species an ecological advantage in phytoplankton community competition under DIP-limited conditions.

关键词： Alkaline phosphatase Dissolved inorganic phosphorus Dissolved organic phosphorus growth Phytoplankton

growth behavior of ultrafine austenite grains in microalloyed steel

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Acta Metallurgica Sinica(English Letters) 2009年第1期22卷 7-12页

作者： Linxiu DU Shengjie YAO Xianghua LIU Guodong WANG State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

Ultrafine austenite gains （UFAGs） with size of 1-5 μm were prepared through repetitive treatment, four times, of rapid heating and quenching, and the growth behaviors of these UFACs during both the reheating and cooling stages were investigated. The results indicated that UFAGs without pinning particles appeared with significant coarsening when the reheating temperature reached 1000 ℃. Although coarsening still occurred in the cooling stage, the growth was obscured during the isothermal holding process at temperatures between 900 ℃ and At3.

关键词： Ultrafine austenite grain growth Microalloyed steel Second-phase particle

growth behavior of spinel in stainless steel slag during cooling process

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Journal of Iron and Steel Research International 2018年第11期25卷 1131-1139页

作者： Long-hu Cao Cheng-jun Liu Qing Zhao Mao-fa Jiang Key Laboratory for Ecological Metallurgy of Multimetallic Ores (Ministry of Education) Northeastern University Shenyang 110819LiaoningChina School of Metallurgy Northeastern University Shenyang 110819LiaoningChina

Spinel is an appropriate phase for sequestrating chromium in stainless steel slag to prevent chromium from polluting,and the crystal size of spinel has a significant effect on the stability of chromium and the extraction efficiency of *** enrichment behavior of chromium in spinel during cooling process was investigated,and the growth process of spinel was studied based on the crystal size distribution *** results showed that the enrichment degree of chromium in spinel increased from 88.5% to nearly 100% during the cooling process from 1773 to 1573 K at a rate of 5 K/*** mean diameter of spinel in stainless steel slag had an obvious growth in the cooling process,and a rapid growth of spinel occurred during the cooling process from 1623 to 1523 *** results indicated that the leaching amount of chro- mium could reduce to less than 0.01 mg/L by controlling the cooling *** growth mechanism of spinel was investigated and proposed to consist of two stages:in the first stage,the spinel was in the surface-controlled growth with a decaying nucleation rate from 1773 to 1573 K,and in the second stage,the growth mechanism was transformed to supply- controlled Ostwald ripening-below 1573 K.

关键词： Stainless steel slag Spinel Chromium growth mechanism Crystal size distribution

growth mechanism of CsPbBr3 perovskite nanocrystals by a co-precipitation method in a CSTR system

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Nano Research 2019年第1期12卷 121-127页

作者： Jibin Zhang Lianwei Fan Junli Li Xiangfu Liu Rongwen Wang Lei Wang Guoli Tu Wuhan National Laboratory far Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

A co-precipitation method based on supersaturated recrystallization in a continuous stirred-tank reactor(CSTR)system was applied to un cover the growth mecha nism of CsPbBr3 perovskite nano crystals(NCs).The reacti on rate can be controlled by changi ng the reaction conditions in this CSTR system,which helps us to observe importa nt intermediate stages to gain in sight into the growth mecha nism of these *** effects of the temperature,concentrations of the ligands(oleylamine and oleic acid),and precursor concerttrations during the growth process of CsPbBr3 NCs were discussed in ***,the growth mechanism of CsPbBr3 NCs was investigated in terms of the dynamics and thermodynamics on the basis of experimental *** growth mechanism is a useful guide to large-scale *** synthesized CsPbBr3 NCs were employed for fabrication of both white light-emitting diodes and quantum-dot light-emitting diodes to test their photoelectric properties;the results show that CsPbBr3 NCs show great promise for optoelectronics applications.

关键词： perovskite CsPbBr3 nanocrystals growth mechanism continuous stirred-tank reactor(CSTR)system

growth induced buckling of morphoelastic rod in viscous medium

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Chinese Physics B 2020年第5期29卷 354-360页

作者： Yitong Zhang Shuai Zhang Peng Wang School of Civil Engineering and Architecture University of JinanJinan 250022China

Biological growth is a common phenomenon in nature,and some organisms such as DNA molecules and bacterial filaments grow in viscous *** growth induced instability of morphoelastic rod in a viscous medium is studied in this *** on the Kirchhoff kinetic analogy method,the mechanical model for growing elastic thin rod in the viscous medium is established.A perturbation analysis is used to analyze the stability of the growing elastic rod in the viscous *** apply the results into planar growing ring and get its criterion of *** the criterion into DNA ring to discuss the influence of viscous resistance on its instability.

关键词： growth morphoelastic rod Kirchhoff rod buckling perturbation