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Nano Research 2023年第11期16卷 12706-12712页

作者： Yafei Chen Zhengwei pan Center for Integrative Petroleum Research College of Petroleum Engineering and GeosciencesKing Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

We report the use of CaTiO_(3):pr^(3+)multiband persistent luminescent nanoparticles,which can simultaneously emit red(610 nm),near-infrared(893 nm),and short-wave infrared(1040 nm)photoluminescence and persistent luminescence,as the tracer nanoagents for water tracer *** using a spectrofluorometer,an Si charge-coupled device(CCD)camera and an InGaAs array camera as the detection tools,we evaluated the sensing capabilities of the three emission bands of CaTiO_(3):pr^(3+)nanoparticles in brine water solutions and crude oil/brine water emulsions in both photoluminescence mode and persistent luminescence *** these different detection combinations,the persistent luminescence-based Si CCD camera imaging exhibits the best sensing performance with the detection limits being at a single-digit ppb level for the 610 and 893 nm bands and about 100–200 ppb for the 1040 nm band in both water solutions and crude oil/water emulsions,while the photoluminescencebased Si CCD camera imaging has a much higher detection limit of~10 ppm in water solutions and of~200 ppm in oil/water *** persistent luminescence-based InGaAs array camera imaging to the 1040 nm band has the worst performance with the detection limits higher than 200 ppm for both *** sensing performances of the spectrofluorometer to photoluminescence signals and persistent luminescence signals in the two solutions are about the same,with the detection limits being around 100–200 ppm.

关键词： water tracer CaTiO_(3):pr^(3+)nanoparticles photoluminescence persistent luminescence crude oil/water emulsion detection limit

Comparing Online Performance of EMG Pattern Recognition with and Without Joint Movements

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Journal of Bionic Engineering 2023年第5期20卷 2135-2146页

作者： Lizhi pan Kai Liu Jianmin Li Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education School of Mechanical EngineeringTianjin UniversityTianjin300350China

Our previous study suggested that the subcutaneous muscle displacement caused by joint movements might alter muscle activation patterns and thus affect the classification *** further analyze the effect of joint movements on the online performance of Electromyography(EMG)Pattern Recognition(pr),this study assessed online classification performance with and without joint *** signals were recorded from the dominant forearm of 10 able-bodied subjects under two motion scenarios:Hand and Wrist Joints Unconstrained(HAWJU)and Constrained(HAWJC).Sixth-order autoregressive coefficients and four time-domain features were extracted from EMG *** Discriminant Analysis(LDA)models were trained to perform an online performance evaluation of the limb *** experimental results showed that the four online performance metrics:Motion Selection Time(MST),Motion Completion Time(MCT),Motion Completion Rate(MCR),and Online Classification Accuracy(ONCA)were 0.35 s,1.44 s,97.40%,and 82.61%for HAWJU and 0.37 s,1.47 s,89.70%,and 73.57%for HAWJC,*** outcomes of this study indicated that subcutaneous muscle displacement due to joint movements has a positive effect on online classification *** absence of joint movements may be a physiological factor contributing to the poor online performance of the EMG-pr of transradial *** study can provide a new perspective for improving the online performance of EMG-pr for transradial amputees.

关键词： Electromyography(EMG) Pattern recognition(pr) Joint movements Online performance

Rare Earth Elements(La,Ce,pr)Modified Co/NC Catalyst for Efficient and Stable Ammonia Decomposition to Hydrogen production

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Journal of Wuhan University of Technology(Materials Science) 2024年第6期39卷 1372-1378页

作者： ZHU Yi pan Hongfei State Key Laboratory of Advanced Technology for Materials Synthesis and processing Wuhan University of TechnologyWuhan 430070China National Energy Key Laboratory for New Hydrogen-ammonia Energy Technologies Foshan Xianhu LaboratoryFoshan 528200China

Co/NC catalysts modified with rare earth elements(La,Ce,pr)were prepared by pyrolysis of rare earth elements doped *** experimental results show that the modification of rare earth elements significantly improves the ammonia decomposition activity and stability of the Co/NC *** La-Co/NC catalyst can achieve an 82.3%ammonia decomposition and 18.4 mmol hydrogen production rate at 550℃with a GHSV of 20000 cm^(3)·h^(-1).Furthermore,no obvious performance degradation is observed after 72 hours of reaction for all rare earth elements modified *** is shown that the modification of rare earth elements significantly improves the surface alkalinity and surface chemical state of the catalyst,and thus improves the ammonia decomposition activity of the catalyst.A new type of high-performance ammonia decomposition Co-based catalyst is proposed,and the promoting effect of rare earth elements on the activity of ammonia decomposition is revealed.

关键词： hydrogen carrier hydrogen production ammonia decomposition rare earth elements cobalt-based catalysts

Evidence for a Bulky Unit of a Pillar[5]arene Flipping in the Solid State

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Chinese Journal of Chemistry 2014年第5期32卷 391-395页

作者： Mingguang pan Min Xue Department of Chemistry Zhejiang UniversityHangzhouZhejiang 310027China

It is well known that pillar[5]arenes have two most stable conformations(pS and pr)in their crystal *** of the intramolecular H-bonding interactions,substituents,temperature,solvent and so on,the rotational behaviors of the phenolic units on pillararenes are also *** paper showed some other kinds of conforma-tions in the functionalized pillar[5]arenes and gave evidence for a bulky unit(1,4-methoxycarbonylmethoxybenzene unit)flipping in the solid *** presence of hydrogen bonding facilitated the intermolecular self-assembly in terms of energy-minimized packing in the ***,the main driving force for the flipping of this bulky unit might be both the intramolecular hydrogen bonding between the phenolic units on pillararenes and quadrupolar hy-drogen bonding between the host and *** paper helps us to have a better understanding on the conforma-tions of pillar[5]arenes.

关键词： pillararenes conformation hydrogen bonding hydroquinone 1,4-methoxycarbonylmethoxybenzene

Novel sulfhydryl functionalized covalent organic frameworks for ultra-trace Hg^(2+) removal from aqueous solution

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Journal of Materials Science & Technology 2021年第34期93卷 89-95页

作者： Fei pan Chunyi Tong Zhaoyang Wang Fenghua Xu Xiaofei Wang Baicheng Weng Dawei pan Rilong Zhu College of Chemistry and Chemical Engineering.Advanced Catalytic Engineering Research Center of the Ministry of Education Hunan UniversityChangsha410082.PR China CAS Key Laboratory of Coastal Environmental processes and Ecological Remediation Shandong Key Laboratory of Coastal Environmental ProcessesResearch Center for Coastal Environment Engineering Technology of Shandong ProvinceYantai Institute of Coastal Zone Research.Chinese Academy of Sciences.Yantai 264003PR China University of Chinese Academy of Sciences Beijing100049PR China College of Chemistry and Chemical Engineering Central South UniversityChangsha410083PR China School of Environmental Science and Engineering Hubei Polytechnic UniversityHuangshi435003PR China

Two kinds of novel sulfhydryl functionalized covalent organic frameworks were fabricated as adsorbents for the removal of ultra-trace concentrations of Hg^(2+)from *** two kinds of sulfhydryl functionalized covalent organic frameworks were obtained via a thiol-ene click reaction between the thiol groups of trithiocyanuric acid(TTC)or bismuththiol(BMT)and vinyl groups on the surface of covalent organic *** material structure was characterized by XRD,SEM,EDS,FT-IR,BET,and TG *** to their rich sulfur content,both adsorbents(COF-SH-1 and COF-SH-2)exhibited a high level of selective Hg^(2+)removal from aqueous solution with maximum adsorption capacities of 763.4 mg g^(-1) and526.3 mg g^(-1),***,in the presence of ultra-low concentrations of Hg^(2+)both materials exhibited excellent performance,achieving rapid Hg^(2+)removal at concentrations from 10μg L^(-1) to less than 0.02 ng L^(-1).Analysis of the adsorption mechanism indicates that the sulfur containing chelating groups exhibit a strong binding capacity for Hg^(2+).Results show that the structure determines the performance,with the amount of adsorption sites being related to the adsorption ***,as sulfhydryl functionalized covalent organic frameworks contain an abundance of adsorption sites,these materials can effectively achieve the removal of ultra-low trace Hg^(2+)concentrations and have promising future application potential for the environmental detection of heavy metals.

关键词： Sulfhydryl-functionalized Covalent organic framework Ultra-trace adsorption Mercury adsorption

Vapor-liquid equilibrium modeling for binary system of R152a/R1234ze(E)

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Chinese Journal of Chemical Engineering 2023年第10期62卷 124-131页

作者： Chuang pan Yuande Dai Yiwu Yi Yu Liao School of Advanced Manufacturing Nanchang UniversityNanchang 330031China

At present,the environment impact of refrigerants has been given *** binary mixture R152a/R1234ze(E)is an environmentally friendly refrigerant,which solves problems of poor cooling performance of the R1234ze(E)cycle and flammability of *** order to obtain its basic thermal and physical parameters,it is necessary to carry out vapor-liquid equilibrium(VLE)research,and the cubic equation of states(EOS)is often used in the calculation of the thermodynamic properties of *** this paper,the VLE predicted models for R152a/R1234ze(E)in the temperature range of 298.15-328.15 K were constructed using Soave-Redlich-Kwong(SRK),Peng-Robinson(pr)equations of state(EOS)combined with van der Waals(vd W),Huron-Vidal(HV)mixing rules,*** equilibrium pressures and vapor-phase mole fractions of the models were obtained by calculation,and all four models presented an extreme correlation with the experimental *** it can be concluded that the calculated results of the pr+HV model are closer to the experimental data than those of the other three models,with the average absolute deviation of 0.0027 for vapor-phase mole fraction(AAD(ycal))and the average absolute relative deviation of 0.243%for equilibrium pressure(AARD(pcal)),which provides a basis for accurately calculating the thermophysical properties of the mixture R152a/R1234ze(E).

关键词： Binary mixture Binary interaction coefficient pr+HV model SRK+HV model Vapor-liquid equilibrium

Co-assembled C13-dipeptide hydrogels by Gallic Acid (CA) and epigallocatechin gallate (EGCG) with antibacterial activity

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Food Bioscience 2022年第5期49卷 933-940页

作者： Tan Hu Siyi pan College of Food Science and Technology Huazhong Agricultural UniversityNo.1 Shizishan RoadWuhanHubei430070PR China Key Laboratory of Environment Correlative Dietology(Huazhong Agricultural University) Ministry of EducationChina Hubei Key Laboratory of Fruit&Vegetable processing&Quality Control(Huazhong Agricultural University) WuhanHubei430070PR China

The self-assembled peptide-based hydrogels have been widely utilized in ***,the self-assembled hydrogels still have some shortages such as low mechanical properties and hydrogel ***,we designed two co-assembled C_(13)-WS hydrogels conjugated by Gallic Acid(CA)and Epigallocatechin Gallate(EGCG).The introduction of CA and EGCG into C_(13)-WS hydrogels can significantly improve the mechanical properties and hydrogel *** storage modulus(G’)values of co-assembled C_(13)-WS/CA and C_(13)-WS/EGCG were 13.33 KPa and 16 KPa,*** transmission electron microscope(TEM)results,CA and EGCG contributed to the rearrangement of C_(13)-WS molecules during ***,the self-/co-assembled C_(13)-WS hydrogels showed antimicrobial activity against ***,***,and *** introduction of CA and EGCG significantly enhanced the antibacterial activity of C_(13)-WS *** findings provide a novel strategy for the development of stable supramolecular antibacterial short peptide hydrogels through co-assembly.

关键词： Peptide hydrogels C_(13)-dipeptides Co-assembly Antibacterial activity

CF_4 decomposition over solid ternary mixture NaF-Si-MO(MO=La_2O_3,CeO_2,pr_6O-(11),Nd_2O_3,Y_2O_3)

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Journal of Natural Gas Chemistry 2012年第2期21卷 109-112页

作者： Yanfei pan Xianjun Niu Yanan Wang Xiufeng Xu School of Chemistry and Chemical Engineering Yantai UniversityYantai 264005ShandongChina

A solid ternary mixture consisting of NaF,silicon and one metal oxide such as La2O3,CeO2,pr6O11,Nd2O3,and Y2O3 was prepared and usedas de-fluorinated reagent for CF4 *** results show that 90% conversion of CF4 can be reached initially over NaF-Si-La2O3,NaF-Si-CeO2,NaF-Si-Nd2O3,and NaF-Si-Y2O3 at 850 *** fresh and used reagents were characterized using XRD and XPS *** was found that the active components of NaF and metal oxides in NaF-Si-CeO2,NaF-Si-pr6O11,NaF-Si-Nd2O3,and NaF-Si-Y2O3 weretransformed into inert phases of mixed metal fluorides and silicates,respectively,resulting in an ineffective utilization of these de-fluorinatedreagents,whereas no inert phases from NaF and La2O3 can be observed in the used NaF-Si-La2O3,indicating the NaF-Si-La2O3 reagent couldbe utilized more efficiently than the other reagents in CF4 decomposition.

关键词： CF4 decomposition solid ternary mixture NaF-Si-MO(MO = La2O3 CeO2 pr6O11 Nd2O3 Y2O3) de-fluorinated reagent reactivity

Achieving high strength and rapid degradation in Mg-Gd-Ni alloys by regulating LPSO phase morphology combined with extrusion

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Journal of Magnesium and Alloys 2024年第6期12卷 2312-2326页

作者： Kai Ma Jingfeng Wang Yinhong Peng Chaoneng Dai Yuanlang pan Ye Wang Danqian Wang Jinxing Wang Yanlong Ma Fusheng pan College of Materials Science and Engineering Chongqing UniversityChongqing 400044PR China National Engineering Research Center for Magnesium Alloys Chongqing 400044PR China College of Chemistry and Chemical Engineering Chongqing UniversityChongqing 401331PR China College of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054PR China

In this study,Mg-13.2Gd-4.3Ni alloys containing continuous bulk-shaped long-period stacking ordered(LPSO),lamellar LPSO,and a small amount of eutectic phase were prepared,and the evolution of microstructure at different extrusion temperatures and its influence on mechanical and degradation properties as well as corrosion mechanism were *** before extrusion can effectively promote the precipitation of lamellar LPSO in ***400 with higher volume fraction of non-DRXed grains exhibited higher strength,which was mainly due to strong texture,high dislocation density,and high volume fraction of lamellar *** EX420 with higher volume fraction of DRXed grains showed higher degradation rate,which was mainly due to the higher density of grain *** EX400 exhibited excellent comprehensive properties with tensile yield strength(TYS)of 334 MPa,ultimate tensile strength(UTS)of 484 MPa and elongation(EL)of 7.4%,ultimate compressive strength(UCS)of 638 MPa and compressive yield strength(CYS)of 443 MPa,degradation rate of 86.1 mg/cm^(2)/h at 93℃in 3 wt.%KCl solution.

关键词： Mg-Gd-Ni alloys LPSO Mechanical properties Degradation rate

Structure and magnetic properties of mechanically alloyed Tb_(0.2)pr_(0.8)(Fe_(0.4)Co_(0.6))_(1.93) and magnetostriction of its epoxy composite

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Rare Metals 2009年第1期28卷 9-13页

作者： LIU Jinjun LIU Xincai pan Jing JIANG Chengyong State Key Laboratory Base of Novel Functional Materials and preparation Science Faculty of Materials Science and Chemical Engineering Ningbo University Ningbo 315211 China

The C15 Laves phase with composition Tb0.2pr0.8（Fe0.4Co0.6）1.93 was synthesized by mechanical alloying （MA） and subsequent annealing process. The structure and magnetic properties of Tb0.2pr0.8（Fe0.4Co0.6）1.93 were investigated by means of X-ray diffraction （XRD）, a vibrating sample magnetometer, and a standard strain technique. The effect of annealing on the structure and magnetic properties was studied. The analysis of XRD shows that the high pr-content Tb0.2pr0.8（Fe0.4Co0.6）1.93 alloy with the single phase of MgCu2-type structure can be successfully synthesized by MA method. The sample annealed at 450℃ is found to have a coercivity of 196 kA/m at room temperature. An epoxy/Tb0.2pr0.8（Fe0.4Co0.6）1.93 composite was produced by a cold isostatic pressing technique. A large magnetostriction of 400 ppm, at an applied magnetic field of 800 kA/m, was found for the composite. The epoxy-bonded Tb0.2pr0.8（Fe0.4Co0.6）1.93 composite combines a high magnetostriction with a significant coercivitv, which is a oromising magnetostrictive material.

关键词： mechanical alloying magnetostriction structure magnetic properties magnetostrictive composites