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Magnetic Fe3O4@mTiO2-AIPA Microspheres for Separation of Phosphoproteins and Non-phosphoproteins

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Journal of Wuhan University of Technology(Materials Science) 2019年第3期34卷 752-759页

作者： TANG qiuhan lu qi qiNG Guangyan School of Chemistry Chemical Engineering and LifeScienceWuhan University of TechnologyWuhan430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China Research &Development Center Jushi Group Co.UdTongxiang314500China

A novel phosphoprotein separation material was developed, which is constructed by a magnetic mesoporous Fe3 O4@TiO2（Fe3 O4@mTiO2） microsphere and a 5-aminoisophthalic acid（AIPA） monolayer that provides additional binding sites toward phosphate groups. The results of characteristic experiments demonstrated that Fe3 O4@mTiO2-AIPA had good dispersability, high magnetic susceptibility, and satisfactory grafting ratio of AIPA, ascribed to the large specific surface area of the inorganic substrate. Taking advantages of these features, Fe3 O4@mTiO2-AIPA was successfully utilized to separate α-casein（a typical phosphoprotein） and bovine serum albumin（BSA, a typical non-phosphoprotein） from their mixtures（molar ratio = 1:2）. Through adjusting pH and polarity of solutions, the BSA and α-casein were respectively enriched in washing fraction and elution fraction. This result displays the good potential of Fe3 O4@mTiO2-AIPA for application in phosphoprotein enrichment.

关键词： magnetic microsphere phosphoprotein separation α-casein

Global sources, emissions, transport and deposition of dust and sand and their effects on the climate and environment： a review

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Frontiers of Environmental Science & Engineering 2017年第1期11卷 35-43页

作者： Feng Wang Xueqiu Zhao Cynthia Gerlein-Safdi Yue Mu Dongfang Wang qi lu Institute of Desertification Studies Chinese Academy of Forestry Beijing 100091 China School of Resources and Environment Anhui Agricultural University Hefei 230036 China Department of Civil and Environmental Engineering Princeton University Princeton NJ 08544 USA

Dust and Sand Storms （DSS） originating in deserts in arid and semi-arid regions are events raising global public concern. An important component of atmospheric aerosols, dust aerosols play a key role in climatic and environmental changes at the regional and the global scale. Deserts and semi-deserts are the main source of dust and sand, but regions that undergo vegetation deterioration and desertification due to climate change and human activities also contribute significantly to DSS. Dust aerosols are mainly composed of dust particles with an average diameter of 2 ***, which can be transported over thousands of kilometers. Dust aerosols influence the radiation budget of the earth- atmosphere system by scattering solar short-wave radiation and absorbing surface long-wave radiation. They can also change albedo and rainfall patterns because they can act as cloud condensation nuclei （CCN） or ice nuclei （IN）. Dust deposition is an important source of both marine nutrients and contaminants. Dust aerosols that enter marine ecosystems after long-distance transport influence phytoplankton biomass in the oceans, and thus global climate by altering the amount of CO2 absorbed by phytoplankton. In addition, the carbonates carried by dust aerosols are an important source of carbon for the alkaline carbon pool, which can buffer atmospheric acidity and increase the alkalinity of seawater. DSS have both positive and negative impacts on human society： they can exert adverse impacts on human＇s living environment, but can also contribute to the mitigation of global warming and the reduction of atmospheric acidity.

关键词： Dust and sand storm Climate effects Radiative forcing Cloud condensation nuclei Precipitation Iron fertilizer

Simulation and characteristics analysis of a wavefield in a thermoelastic medium adopting the rotated staggered-grid pseudospectral method and L-S theory

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Science China Earth Sciences 2021年第8期64卷 1390-1408页

作者： Yuanxie LI Cai LIU Zhiqi GUO Yang LIU Xuan FENG You TIAN qi lu College of Geo-exploration Science and Technology Jilin UniversityChangchun 130026China

The simulation of wave propagation in high-temperature media requires thermoelastic *** this paper,we apply the rotated-staggered-grid pseudo-spectral method(RSG-PSM)to solving thermoelastic governing equations based on L-S theory.A time splitting method is used to solve the stiffness problem of the equations,and we introduce the rotated staggered pseudo-spectral operator and centered pseudo-spectral operator to compute the first-order spatial derivatives and second-order spatial derivatives,*** the case of the heterogeneous-medium model,the Crank-Nicolson explicit method is used instead of the pseudo-spectral method to compute the *** properties and propagation of the thermal coupled wavefield are discussed,and we compare the simulation results obtained using the pseudo-spectral method,staggered-grid pseudo-spectral method,and *** the case of an isotropic homogeneous medium,we obtain stable and highly accurate results using the time splitting method combined with the ***,the algorithm cannot be applied with a large time step when the thermal conductivity changes dramatically,and the algorithm is unstable when the reference temperature has a gradient *** optimal combined application of the mesh generation mode and numerical algorithm is explored,laying a foundation for the extension of these methods to thermoporoelasticity,thermoviscoelasticity,and anisotropy.

关键词： Thermoelastic wave L-S theory Rotated-staggered-grid pseudo-spectral method Seismic wavefield simulation Time splitting method

Ir0/graphdiyne atomic interface for selective epoxidation

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National Science Review 2023年第8期10卷 173-179页

作者： Zhiqiang Zheng lu qi Yaqi Gao Xiaoyu luan Yurui Xue Feng He Yuliang Li Shandong Provincial Key Laboratory for Science of Material Creation and Energy Conversion Science Center for Material Creation and Energy Conversion School of Chemistry and Chemical EngineeringShandong University CAS Key Laboratory of Organic Solids Institute of ChemistryChinese Academy of Sciences School of Chemical Sciences University of Chinese Academy of Sciences

The development of catalysts that can selectively and efficiently promote the alkene epoxidation at ambient temperatures and pressures is an important promising path to renewable synthesis of various chemical products. Here we report a new type of zerovalent atom catalysts comprised of zerovalent Ir atoms highly dispersed and anchored on graphdiyne(Ir0/GDY) wherein the Ir0is stabilized by the incomplete charge transfer effect and the confined effect of GDY natural cavity. The Ir0/GDY can selectively and efficiently produce styrene oxides(SO) by electro-oxidizing styrene(ST) in aqueous solutions at ambient temperatures and pressures with high conversion efficiency of ～100%, high SO selectivity of 85.5%, and high Faradaic efficiency(FE) of 55%. Experimental and density functional theory(DFT) calculation results show that the intrinsic activity and stability due to the incomplete charge transfer between Ir0and GDY effectively promoted the electron exchange between the catalyst and reactant molecule, and realized the selective epoxidation of ST to SO. Studies of the reaction mechanism demonstrate that Ir0/GDY proceeds a distinctive pathway for highly selective and active alkene-to-epoxide conversion from the traditional processes. This work presents a new example of constructing zerovalent metal atoms within the GDY matrix toward selective electrocatalytic epoxidation.

关键词： graphdiyne atom catalyst atomic interface selective epoxidation high-performance

In-situ formation of nitrogen doped microporous carbon nanospheres derived from polystyrene as lubricant additives for anti-wear and friction reduction

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Friction 2024年第3期12卷 439-451页

作者： Yixin WANG qi lu Huijie XIE Shujuan LIU qian YE Feng ZHOU Weimin LIU State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Solid lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

This study presents a nitrogen-doped microporous carbon nanospheres(N@MCNs)prepared by a facile polymerization–carbonization process using low-cost *** N element in situ introduces polystyrene(PS)nanospheres via emulsion polymerization of styrene with cyanuric chloride as crosslinking agent,and then carbonization obtains N@*** as-prepared carbon nanospheres possess the complete spherical structure and adjustable nitrogen amount by controlling the relative proportion of tetrachloromethane and cyanuric *** friction performance of N@MCNs as lubricating oil additives was surveyed utilizing the friction experiment of ball-disc *** results showed that N@MCNs exhibit superb reduction performance of friction and *** the addition of N@MCNs was 0.06 wt%,the friction coefficient of PAO-10 decreased from 0.188 to 0.105,and the wear volume reduced by 94.4%.The width and depth of wear marks of N@MCNs decreased by 49.2% and 94.5%,*** carrying capacity of load was rocketed from 100 to 400 N *** the analysis of the lubrication mechanism,the result manifested that the prepared N@MCNs enter clearance of the friction pair,transform the sliding friction into the mixed friction of sliding and rolling,and repair the contact surface through the repair ***,the tribochemical reaction between nanoparticles and friction pairs forms a protective film containing nitride and metal oxides,which can avert direct contact with the matrix and improve the tribological *** experiment showed that nitrogen-doped polystyrene-based carbon nanospheres prepared by in-situ doping are the promising materials for wear resistance and reducing *** preparing method can be ulteriorly expanded to multi-element co-permeable *** and boron co-doped carbon nanospheres(B,N@MCNs)were prepared by mixed carbonization of N-enriched PS and boric acid,and exhibited high load carrying capacity and good tribolog

关键词： lubricant additives hypercrosslinked polystyrene carbon nanospheres friction reduction anti-wear

Effect of retained austenite on the fracture behavior of a novel press-hardened steel

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Journal of Materials Science & Technology 2023年第4期135卷 34-45页

作者： Zhisong Chai qi lu Jun Hu Lingyu Wang Zhou Wang Jianfeng Wang Wei Xu State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China China Science Laboratory General Motors Global Research&DevelopmentShanghai 201206China

Tensile and bending properties are two critical attributes of press hardened steels(PHSs)for automotive body structural ***,the research on these properties of PHSs with retained austenite(RA),which is introduced to improve the mechanical properties,has not been well *** this study,the effect of RA on the quasi-static uniaxial tensile and three-point bending behaviors has been systematically investigated for a newly developed Cr and Si alloyed *** with various degrees of mechanical stabilities was obtained by tuning the auto-tempering of martensite through the control of the die contact pressure during the press hardening *** stable RA provides the optimal combination of tensile and bending performance,while the PHS with RA of poor mechanical stability has a deteriorated bending toughness as manifested by a reduction of bending angle from approximately 61.6°to56.8°.However,itstensileproperties,incontrast,arethebestintermsof theproductofulti-mate tensile strength and total elongation(15.9 GPa%).This is mainly attributed to the unstable RA on the outermost surface of the bending *** unstable RA can easily transform into brittle martensite under local plane strain and strain gradient conditions in the bending test compared with uniaxial stress in the tensile test,promoting crack initiation and ***,the effect of martensitic auto-tempering or contact pressure on the quantity and stability of RA are also *** study would provide a useful reference to guide hot stamping process optimization for the newly developed Cr and Si-containing press-hardened steel.

关键词： Press-hardened steel Retained austenite Tensile property Bending toughness Crack initiation

Dissipation-induced topological phase transition and periodic-driving-induced photonic topological state transfer in a small optomechanical lattice

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Frontiers of physics 2021年第1期16卷 157-167页

作者： lu qi Guo-Li Wang Shutian Liu Shou Zhang Hong-Fu Wang School of Physics Harbin Institute of TechnologyHarbin 150001China Department of Physics College of ScienceYanbian UniversityYanji 133002China

We propose a scheme to investigate the topological phase transition and the topological state transfer based on the small optomechanical lattice under the realistic parameters *** find that the optomechanical lattice can be equivalent to a topologically nontrivial Su-Schrieffer Heeger(SSH)model via designing the effective optomechanical ***,the optomechanical lattice experiences the phase transition between topologically nontrivial SSH phase and topologically trivial SSH phase by controlling the decay of the cavity field and the opto mechanical *** stress that the to pological phase transition is mainly induced by the decay of the cavity field,which is counter-intuitive since the dissipation is usually detrimental to the ***,we investigate the photonic state transfer between the two cavity fields via the topologically protected edge channel based on the small optomechanical *** find that the quantum st ate transfer assisted by the topological zero energy mode can be achieved via implying the external lasers with the periodical driving amplitudes into the cavity *** scheme provides the fundamental and the insightful explanations towards the mapping of the photonic topological insulator based on the micro-nano optomechanical quantum optical platform.

关键词： to pological phase transition topological state transfer optomechanical lattice

Improved crop protection and biodiversity of the agroecosystem by reduced tillage in rice paddy ffelds in southern China

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Journal of Integrative Agriculture 2022年第8期21卷 2345-2356页

作者： lu qi-qi SONG Yuan-feng PAN Ke-qing LI Yun TANG Ming-xin ZHONG Guo-hua LIU Jie Key Laboratory of Crop Integrated Pest Management in South China Ministry of Agriculture and Rural Affairs/Key Laboratory of Natural Pesticide and Chemical BiologyMinistry of Education/South China Agricultural UniversityGuangzhou 510640P.R.China

Agricultural sustainability has benefited from the broad adoption of conservation agriculture(CA)practices for decades,in which the reduction of mechanical disturbances to soil(also known as reduced tillage,RT)is one of the most essential principles for CA *** studies have recommended the advantages of CA practices in the promotion of biodiversity,but the integrated impacts on crop productivity and biodiversity remain *** CA has been applied in rice production in the subtropical area of southern China for several years,the effects of CA,particularly the RT methods,need to be evaluated for the local and long-term *** this study,we established an integrated network to illustrate how the reduction of tillage intensity influenced organisms including invertebrates(such as rice pests and their predators),pathogens and weeds,and then led to an impact on rice *** two-year study demonstrated that major rice pests,such as rice planthoppers,stem borers and apple snails,were effectively controlled by RT ***,the occurrence of common diseases declined with less *** to the conventional tillage(CT)treatment,the density of weeds in paddy fields deceased significantly in the RT *** addition,the diversity and richness of pest predators increased remarkably in paddy fields where either reduced or no tillage was applied,which highlighted the significance of a CA strategy for the promotion of biodiversity in the *** importantly,the rice yield gradually increased after the two-year reduction of *** together,our results suggest that the reduction of tillage intensity is beneficial for the protection of rice crops from various pests,and facilitates the sustainability of the agroecosystem and rice yield,which provides a solid basis and novel insights for the establishment of sustainable agroecosystems by CA-related practices in rice production in southern China.

关键词： conservation agriculture reduced tillage biodiversity pest control sustainable agriculture

Structure and electrochemical characteristics of Mg–Ti–Ni-based electrode alloys synthesized by mechanical milling

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Journal of Iron and Steel Research International 2021年第10期28卷 1329-1340页

作者： Zhong-hui Hou Xin Wei Wei Zhang Ze-ming Yuan Hui Yong qi-lu Ge Department of Functional Material Research Central Iron and Steel Research InstituteBeijing100081China Inner Mongolia University of Science and Technology Baotou014010Inner MongoliaChina

The vacuum induction melting was adopted to fabricating Mg_(50−x)Ti_(x)Ni_(45)Al_(3)Co_(2)(x=0,1,2,3,4 at.%)composites protected by the high-purity helium ***,the surface modification treatment of the as-cast alloys was carried out by mechanically coating *** amorphous and nanocrystalline Mg_(50−x)Ti_(x)Ni_(45)Al_(3)Co_(2)(x=0–4)+50 wt.%Ni hydrogen storing alloys as the negative materials in batteries were prepared through ball milling,and the influences of milling time and Ti dosage on the structure and electrochemical hydrogen storing behaviors of the corresponding samples were studied in *** electrochemical testing reveals that the as-milled alloys have excellent performances and can finish the electrochemical hydrogenation and dehydrogenation at indoor *** the first cycle without activation,the ball milling alloy obtains the maximum value of discharge *** capacity and cyclic steadiness of the composites conspicuously grow as Ti content and milling duration ***,the capacity retaining rate at 100th cycle and the discharge capacity of 30 h milling samples augment from 53%to 78%and from 435.2 to 567.2 mAh/g with changing Ti content from 0 to *** same performances of the alloy(x=4)are enhanced from 61%to 78%and from 379.9 to 567.2 mAh/g,respectively,with extending milling ***,high rate discharge ability,potential-step measurements,potentiodynamic polarization curves and electrochemical impedance spectrum manifest that the electrochemical kinetics properties can achieve significant amelioration as Ti content varies and milling duration is extended.

关键词： MgNi-based alloy Ti substitution of Mg Surface modification Mechanical milling Electrochemical performance