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Applied Mathematics and Mechanics(English Edition) 2022年第2期43卷 203-218页

作者： Shunzu ZHANG Qianqian HU wenjuan zhao School of Civil and Hydraulic Engineering Ningxia UniversityYinchuan750021China

This paper presents a theoretical model for the size-dependent band structure of magneto-elastic phononic crystal(PC)nanoplates according to the Kirchhoff plate theory and Gurtin-Murdoch theory,in which the surface effect and magneto-elastic coupling are *** introducing the nonlinear coupling constitutive relation of magnetostrictive materials,Terfenol-D/epoxy PC nanoplates are carried out as an example to investigate the dependence of the band structure on the surface effect,magnetic field,pre-stress,and geometric *** results show that the surface effect has promotive influence on dispersion curves of the band structure,and the band gaps can be improved gradually with the increase in the material intrinsic ***,the band gaps exhibit obvious nonlinear coupling characteristics owing to the competition between the magnetic field and the *** considering the surface effect and magneto-elastic coupling,the open and closed points of band gaps are found when the lattice constant to thickness ratio *** study may provide a method for flexible tunability of elastic wave propagation in magneto-elastic PC nanoplates and functional design of highperformance nanoplate-based devices.

关键词： magneto-elastic phononic crystal nanoplate surface effect magnetic field band gap

Synergistic activation of smithsonite with copper-ammonium species for enhancing surface reactivity and xanthate adsorption

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International Journal of Mining Science and Technology 2023年第4期33卷 519-527页

作者： wenjuan zhao Bin Yang Yahui Yi Qicheng Feng Dianwen Liu State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Mineral Resources Kunming University of Science and TechnologyKunming 650093China

Copper ions(Cu^(2+))are usually added to activate the sulfidized surface of zinc oxide minerals to enhance xanthate attachment using sulfidization xanthate flotation *** adsorption of Cu^(2+)and xanthate on the sulfidized surface was investigated in various systems,and its effect on the surface hydrophobicity and flotation performance was revealed by multiple analytical methods and experiments.X-ray photoelectron spectroscopy(XPS)and time-of-flight secondary ion mass spectrometry(To F-SIMS)characterization demonstrated that the adsorption of Cu^(2+)on sulfidized smithsonite surfaces increased the active Cu—S content,regardless of treatment in any activation *** sulfidized surface pretreated with NH_(4)^(+)-Cu^(2+)created favorable conditions for the adsorption of more Cu^(2+),significantly enhancing the smithsonite *** potential determination,ultraviolet(UV)-visible spectroscopy,Fourier transform-infrared(FT-IR)measurements,and contact angle detection showed that xanthate was chemically adsorbed on the sulfidized surface,and its adsorption capacity in various systems was illustrated from qualitative and quantitative *** comparison to the Na2S–Cu^(2+)and Cu^(2+)–Na2S–Cu^(2+)systems,xanthate exhibited a higher adsorption capacity on sulfidized smithsonite surfaces in NH_(4)^(+)-Cu^(2+)–Na2S–Cu^(2+)***,activation with Cu^(2+)–NH4+synergistic species prior to sulfidization significantly enhanced the mineral surface hydrophobicity,thereby increasing its flotation recovery.

关键词： Smithsonite surface reactivity Synergistic activation Copper-ammonium species Surface hydrophobicity Enhanced recovery

Flotation of copper oxide minerals:A review

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International Journal of Mining Science and Technology 2022年第6期32卷 1351-1364页

作者： Qicheng Feng Wenhang Yang Shuming Wen Han Wang wenjuan zhao Guang Han State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Mineral Resources Kunming University of Science and TechnologyKunming 650093China

Copper oxide minerals are important copper resources,which include malachite,azurite,chrysocolla,cuprite,*** is the most widely used method for the enrichment of copper oxide minerals in the mineral processing *** this paper,the surface properties of copper oxide minerals and their effects on the mineral flotation behavior are systematically *** flotation methods of copper oxide minerals and the interaction mechanism with reagents are reviewed in *** methods include direct flotation(using chelating reagents or a fatty acid as collector),sulfidization flotation(using xanthate as collector),and activation flotation(using chelating reagents,ammonium/amine salts,metal ions,and oxidant for activation).An effective way to realize efficient flotation of copper oxide minerals is to increase active sites on the surface of copper oxide minerals to enhance the interaction of collector with the mineral ***,various perspectives for further investigation on the efficient recovery of copper oxide minerals are proposed.

关键词： Copper oxide minerals Direct flotation Sulfidization flotation Activation flotation

A novel sulfidization system for enhancing hemimorphite flotation through Cu/Pb binary metal ions

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International Journal of Mining Science and Technology 2024年第12期34卷 1741-1752页

作者： Feng, Qicheng Zhang, Yingchao Zhang, Ga Han, Guang zhao, wenjuan State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 China Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Mineral Resources Kunming University of Science and Technology Kunming 650093 China

The low reactivity of hemimorphite surfaces hinders the effective action of sulfidizing agents and xanthate, resulting in unsatisfactory flotation performance. To enhance the surface reactivity of hemimorphite with sulfidizing agents and xanthate, Cu/Pb binary metal ions were introduced into the sulfidization flotation system to enhance the sulfidization process and thereby promote hemimorphite flotation. The flotation results demonstrated a remarkable improvement in the hemimorphite flotation recovery when Cu/Pb binary metal ions were added prior to sulfidization. The flotation recovery of hemimorphite increased from less than 5% to over 80%. After strengthening the sulfidization of hemimorphite with Cu/Pb binary metal ions, the mineral surface formed multicomponent sulfide products composed of zinc, copper, and lead sulfide. The reactivity of the copper-lead sulfide components exceeds that of the zinc sulfide component;thus, the enhancement by Cu/Pb binary metal ions not only increases the content of sulfide products on the hemimorphite surface but also augments their reactivity. Contact angle and adsorption experiments indicated that after enhanced sulfidization with Cu/Pb binary metal ions, the hemimorphite surface adsorbed a greater amount of xanthate, significantly increasing the mineral surface hydrophobicity. Consequently, the enhanced sulfidization by Cu/Pb binary metal ions effectively improved the flotation behavior of hemimorphite, presenting an innovative sulfidization system for the flotation recovery of zinc silicate minerals in zinc oxide ores. © 2024

关键词： Flotation agents

Spatial distribution of health risks for residents located close to solvent-consuming industrial VOC emission sources

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Journal of Environmental Sciences 2021年第9期33卷 38-48页

作者： Di Wang Xuan Li Xinmin Zhang wenjuan zhao Weiqi Zhang Shuaifeng Wu Xia Shao Lei Nie State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Beijing Key Laboratory of Urban Atmospheric Volatile Organic Compounds Pollution Control and Application Beijing Municipal Research Institute of Environment ProtectionBeijing 100037China China Institute of Water Resources and Hydropower Research Beijing 100038China

Emissions derived from the consumption of organic solvents have been proven to be the primary industrial source of volatile organic compounds(VOCs).In conjunction with epidemiologic studies, water-based paints(WBPs) and solvent-based paints(SBPs) were selected as representatives of newly developed solvents and traditional solvents, respectively,to simulate the effects of consuming solvents emitted during industrial *** non-carcinogenic and carcinogenic risks to residents near emission sources were studied in *** results showed that the spatial distribution of health risks varied with meteorological conditions and type of emission source, and the prevailing wind direction strongly affected the distribution range and shape of the influenced *** areas of influence maximized on heavy-polluting days for both WBP and SBP emission sources with the total span reaching 804 m and 16 km, respectively;meanwhile, the areas of influence for carcinogenic risk resulting from WBP emission sources were 1.2 and 2.3 times greater than those measured on fine and rainy days, respectively, and 1.8 and 2.9 times greater for SBP emission *** with WBPs, the total spans of negatively influenced regions resulting from SBP emission sources were 10.4, 12.5 and 19.9 times greater on fine, rainy and heavypolluting days, ***, carcinogenic risk was the dominant health threat for populations residing close to solvent-consuming industrial emission *** findings suggest that newly developed solvents are capable of significantly reducing consequent health threats, nevertheless, they could still pose occasional threats to nearby residents under specific meteorological conditions.

关键词： Secondary receptor Spatial distribution Solvent-consuming emission source Potential health risk Acquirable risk-free region

The Effects of Simulated Microgravity on Immune Function of Macrophages

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医用生物力学 2019年第A1期34卷 129-130页

作者： Guolin Shi Sufang Wang wenjuan zhao Hui Yang School of Life Sciences Northwestern Polytechnical UniversityXi’an710072China Research Center of SpecialEnvironmental Biomechanics&Medical Engineering Northwestern Polytechnical UniversityXi’an710072China Medical Research Institute Northwestern Polytechnical UniversityXi’an710072China

Since the 1 960 s,many successful space missions have highlighted the advantages and necessity of humans in the exploration of space,but scientists have long worried about the adverse effects of spaceflight on *** flight and models that create conditions similar to those that occur during space flight have been shown to deleteriously affect a variety of immunological *** mechanisms and biomedical consequences of these changes remain to be *** experiments in an environment of true microgravity requires a roundtrip ticket into space,a feat that is both expensive and *** microgravity(SMG)models allow scientists to gather preliminary data without the cost and logistical challenges of *** objective of the present study was to evaluate the effects of SMG on immunity function of macrophages that exposed to RPM and RCCS *** many studies have demonstrated that alterations occur in the immune system as a result of space travel,the level at which these mechanisms exert their effect,at the level of the mature immune cell or earlier at the progenitor or stem cell stage is not *** particular,macrophages,as one of the most important immune cells and play a key role in both specific and non-specific immunity,did not have received much ***,in our study,we mainly study the influence of microgravity on the immune function of *** this study,we evaluated the immune dysfunction of macrophages under ***,we found that the morphology and structure of the macrophages were changed,specifically,we observed that there were more protrusions on cell surface and the cells were shrinking significantly after exposure to ***,we demonstrated that under simulated microgravity(SMG)conditions,the phagocytic and proliferative functions of macrophages were significantly ***,several processes,including surface receptor expression,cytoskeleton,and cytokines secreted

关键词： simulated microgravity effect RAW 264.7 phagocytosis cytoskeleton antigen processing and presentation

Electrochemical characteristics of amorphous MgTi_xNi(x = 0,0.1,and 0.2) hydrogen storage alloys

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Rare Metals 2010年第5期29卷 486-490页

作者： LIU Suqin,zhao wenjuan,HUANG Kelong,and HUANG Hongxia College of Chemistry and Chemical Engineering,Central South University,Changsha 410083,China College of Chemistry and Chemical Engineering Central South University Changsha China

MgTixNi （x = 0, 0.1, and 0.2） alloys were successfully prepared by mechanical alloying （MA）, and the influence of milling time on the electrochemical characteristics of the electrodes was discussed. MgTixNi alloys after 90 h milling displayed the best electrochemical performance The X-ray diffraction patterns showed that the alloy ball-milled for 90 h was amorphous with a widened diffraction peak. The charge-discharge tests indicated that these alloys had good electrochemical activation properties, and the MgTi0.2Ni alloy electrode exhibited the best cycle performance. The initial discharge capacity of the MgTi0.2Ni alloy reached up to 401.1 mAh·g^-1, and the retention rate of capacity was 31.0% after 30 cycles, much higher than that of MgNi （17.3%）. The Tafel polarization curves revealed that Ti addition could enhance the anticorrosion performance of these alloys in alkali solution, which was responsible for the ameliorated cyclic stability of these alloy electrodes.

关键词： hydrogen storage alloys titanium electrochemical properties mechanical alloying

Macrophage LMO7 deficiency facilitates inflammatory injury via metabolic-epigenetic reprogramming

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Acta Pharmaceutica Sinica B 2023年第12期13卷 4785-4800页

作者： Shixin Duan Xinyi Lou Shiyi Chen Hongchao Jiang Dongxin Chen Rui Yin Mengkai Li Yuseng Gou wenjuan zhao Lei Sun Feng Qian Shanghai Frontiers Science Center of Drug Target Identification and Delivery National Key Laboratory of Innovative ImmunotherapyEngineering Research Center of Cell&Therapeutic AntibodyMinistry of EducationSchool of PharmacyShanghai Jiao Tong UniversityShanghai 200240China

Inflammatory bowel disease(IBD)is a formidable disease due to its complex ***,as a major immune cell population in IBD,are crucial for gut ***,it is still unveiled how macrophages modulate ***,we found that LIM domain only 7(LMO7)was downregulated in pro-inflammatory macrophages,and that LMO7 directly degraded 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3(PFKFB3)through K48-mediated ubiquitination in *** an enzyme that regulates glycolysis,PFKFB3 degradation led to the glycolytic process inhibition in macrophages,which in turn inhibited macrophage activation and ultimately attenuated murine ***,we demonstrated that PFKFB3 was required for histone demethylase Jumonji domaincontaining protein 3(JMJD3)expression,thereby inhibiting the protein level of trimethylation of histone H3 on lysine 27(H3K27me3).Overall,our results indicated the LMO7/PFKFB3/JMJD3 axis is essential for modulating macrophage function and IBD *** LMO7 or macrophage metabolism could potentially be an effective strategy for treating inflammatory diseases.

关键词： Inflammatory bowel disease Macrophage LMO7 Ubiquitination PFKFB3 JMJD3

Electronic structure of exfoliated millimeter-sized monolayer WSe2 on silicon wafer

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Nano Research 2019年第12期12卷 3095-3100页

作者： wenjuan zhao Yuan Huang Cheng Shen Cong Li Yongqing Cai Yu Xu Hongtao Rong Qiang Gao Yang Wang Lin zhao Lihong Bao Qingyan Wang Guangyu Zhang Hongjun Gao Zuyan Xu Xingjiang Zhou Guodong Liu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China Beijing Academy of Quantum Information Sciences Beijing 100193China

The mono layer WSe2 is in teresting and important for future application in nanoelectronics,spintronics and valleytronics devices,because it has the largest spin splitting and Ion gest valley coherence time among all the known monolayer transition-metal dichalcogenides(TMDs).Toobtain the large-area monolayer TMDs'crystal is the first step to manu facture scalable and high-performance electronic *** this letter,we have successfully fabricated millimeter-sized mono layer WSe2 single crystals with very high quality,based on our improved mecha nicalexfoliation *** such superior samples,using standard high resolution angle-resolved photoemission spectroscopy,we didcomprehe nsive electronic band structure measurements on our mono layer *** overall band features point it to be a 1.2 eV direct bandgap semico *** spin splitting of the valence band at K point is found as 460 meV,which is 30 meV less than the corresponding band splitting in its bulk *** effective hole masses of valence bands are determined as 2.344 me atГ,and 0.529 me as well as 0.532 meat K for the upper and lower branch of splitting ban ds,*** screening effect from substrate is shown to substa ntially impact onthe electronic *** results provide importa nt insights into band structure engineering in mono layer *** mono layer WSe2 crystals may constitute a valuable device platform.

关键词： transition-metal dichalcogenides WSe2 monolayer electronic structure angle-resolved photoemission spectroscopy

Livelihood Capital and Livelihood Diversification for Different Farmers in Yuanjiang Dry-Hot River Valley

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Asian Agricultural Research 2016年第3期8卷 17-21,26页

作者： wenjuan zhao Shilong YANG Xiao WANG School of Resource Environment and Earth Science Yunnan University Yunnan Institute of Geography

Under the analytical framework of sustainable livelihoods,we establish the evaluation indicator system for farmers' livelihood capital,to evaluate the current livelihood capital and livelihood diversification for different farmers in the Dai nationality region of Xinping County in the Yuanjiang dry-hot river valley area,and discuss the relationship between livelihood capital and livelihood diversification. Studies have shown that the mode dominated by agriculture,supplemented by non-agricultural activities,combined with breeding,is the commonly used livelihood strategy for farmers in this region. As farmers change from pure agriculture to non-agriculture,their total livelihood capital and nonagricultural livelihood diversification index will increase,while agricultural livelihood diversification index will decrease. In the meantime,their livelihood activities gradually shift from agricultural to non-agricultural ones,which is mainly reflected in the combination of both agricultural and non-agricultural activities. Regression analysis on livelihood capital and livelihood diversification shows that natural and physical capital is the basis of realizing agricultural livelihood diversification. Farmers with rich natural and physical capital will prefer agricultural livelihood strategies. While financial and human capital is the driving force for farmers' transition from pure agriculture to non-agriculture.

关键词： Livelihood capital Livelihood diversification Regression analysis Yuanjiang dry-hot valley