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Chemical Research in Chinese Universities 2024年第3期40卷 521-528页

作者： SHAO Chen guo Ru LI Hui wang Xiaozhong YANG Qingfeng lai Xiaoyong State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering School of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021P.R.China

Acetone is a tracer for monitoring air quality and a potential breath maker for diabetes. It remains a great challenge for current portable sensors to sensitively and selectively detect acetone at low-ppb (part per billion) level. Herein, we present an ordered mesoporous nickel oxide (NiO) with both large mesopores and ultrathin crystalline frameworks for the detection of low-ppb acetone. The ordered mesoporous NiO replicas with predominant large mesopores of 11 nm, high specific surface areas of 121–128 m2/g and ultrathin crystalline frameworks of 5 nm were synthesized by the nanocasting method and the crystalline properties of NiO frameworks were adjusted by changing the annealing temperature from 300℃ to 750℃, which resulted in different contents of oxygen deficient on the surface of ultrathin frameworks. The gas-sensing properties for all the NiO samples were investigated and the ordered large-pore mesoporous NiO (NiO-600) with maximum oxygen deficient obtained at 600℃ exhibited the highest response (R_(gas)/R_(air)−1=2.9) toward acetone (1 ppm, ppm: part per million), which is 3.4 and 30 times larger than those for common mesoporous NiO obtained at 300℃ and bulk NiO. Notably, a low detection limit (2 ppb), good selectivity and cycling stability were also observed in NiO-600.

关键词： Mesoporous semiconductor NiO Gas sensing Acetone

Peracetic acid(PAA)-based pretreatment effectively improves medium-chain fatty acids(MCFAs)production from sewage sludge

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Environmental Science and Ecotechnology 2024年第4期20卷 154-166页

作者： Yufen wang Haixiao guo Xuecheng Li Xueming Chen lai Peng Tingting Zhu Peizhe Sun Yiwen Liu School of Environmental Science and Engineering Tianjin UniversityTianjin300072China Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology College of Environment and Safety EngineeringFuzhou UniversityFujian350116China Hubei Key Laboratory of Mineral Resources Processing and Environment Wuhan University of TechnologyLuoshi Road 122WuhanHubei430070China School of Resources and Environmental Engineering Wuhan University of TechnologyLuoshi Road 122WuhanHubei430070China

Peracetic acid(PAA),known for its environmentally friendly properties as a oxidant and bactericide,is gaining prominence in decontamination and disinfection *** primary product of PAA oxidation is acetate that can serve as an electron acceptor(EA)for the biosynthesis of medium-chain fatty acids(MCFAs)via chain elongation(CE)***,PAA-based pretreatment is supposed to be beneficial for MCFAs production from anaerobic sludge fermentation,as it could enhance organic matter availability,suppress competing microorganisms and furnish EA by providing ***,such a hypothesis has rarely been *** we reveal that PAA-based pretreatment leads to significant exfoliation of extracellular polymeric substances(EPS)from sludge flocs and disruption of proteinic secondary structures,through inducing highly active free radicals and singlet *** production of MCFAs increases substantially to 11,265.6 mg COD L^(-1),while the undesired byproducts,specifically long-chain alcohols(LCAs),decrease to 723.5 mg COD L^(-1).Microbial activity tests further demonstrate that PAA pretreatment stimulates the CE process,attributed to the up-regulation of functional genes involved in fatty acid biosynthesis *** comprehensive findings provide insights into the effectiveness and mechanisms behind enhanced MCFAs production through PAA-based technology,advancing our understanding of sustainable resource recovery from sewage sludge.

关键词： Sewage sludge Medium-chain fatty acids(MCFAs) Extracellular polymeric substances(EPS) Peracetic acid(PAA) Metabolic activity

Metal-N_(4)model single‐atom catalyst with electroneutral quadri‐pyridine macrocyclic ligand for CO_(2)electroreduction

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Carbon Energy 2024年第8期6卷 122-133页

作者： Jian‐Zhao Peng Yin‐Long Li Yao‐Ti Cheng Fu‐Zhi Li Bo Cao Qing wang Xian Yue guo‐Tao lai Yang‐Gang wang Jun Gu Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdongChina Institute for Catalysis Hokkaido UniversitySapporoJapan

Metal–N–C single‐atom catalysts,mostly prepared from pyrolysis of metalorganic precursors,are widely used in heterogeneous *** metal sites with diverse local structures coexist in this type of material and it is challenging to characterize the local structure,a reliable structure–property relationship is difficult to *** macrocyclic complexes adsorbed on carbon support are well‐defined models to mimic the singleatom ***–N_(4)site with four electroneutral pyridine‐type ligands embedded in a graphene layer is the most commonly proposed structure of the active site of single‐atom catalysts,but its molecular counterpart has not been *** this work,we synthesized the conjugated macrocyclic complexes with a metal center(Co,Fe,or Ni)coordinated with four electroneutral pyridinic ligands as model catalysts for CO_(2)*** comparison,the complexes with anionic quadri‐pyridine macrocyclic ligand were also *** Co complex with the electroneutral ligand expressed a turnover frequency of CO formation more than an order of magnitude higher than that of the Co complex with the anionic *** ab initio molecular dynamics simulations based on the well‐defined structures of the model catalysts indicate that the Co complex with the electroneutral ligand possesses a stronger ability to mediate electron transfer from carbon to CO_(2).

关键词： ab initio molecular dynamics CO_(2)reduction electrocatalysis model catalyst single‐atom catalyst

On the role of sliding friction effect in nonlinear tri-hybrid vibration-based energy harvesting

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1295-1314页

作者： Jiamei wang Siukai lai Chen wang Yiting ZHANG Zhaolin CHEN Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina The Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518057Guangdong ProvinceChina Hebei Key Laboratory of Mechanical Reliability for Heavy Equipments and Large Structures Yanshan UniversityQinghuangdao 066000Hebei ProvinceChina School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

This work aims to develop an experimental investigation into the effectiveness of the sliding-mode approach for hybrid vibration-based energy harvesting.A proposed sliding-mode triboelectric-electromagnetic-piezoelectric energy harvesting model involves a cantilever beam with a tip mass exposed to magnetic and frictional *** experimental findings indicate that the system can achieve its peak inter-well oscillation output within a low-frequency range of 4 Hz–6 *** has a lesser impact on the open-circuit voltage output at an excitation acceleration of 1.5g compared with *** distribution of tri-stability changes with the presence of *** model provides a deeper understanding of the influence of the dry friction coefficient(0.2–0.5) on the interactive behaviors of different generator units.

关键词： sliding mode tri-hybrid energy harvesting friction nonlinear behavior

Influence of bolt dynamic installation on topography characteristics and mechanical behaviors of CFRP interference-fit bolted joints

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Chinese Journal of Aeronautics 2024年第2期37卷 482-500页

作者： Xiaohe wang Zengqiang CAO Yuehaoxuan wang Yingjiang guo School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China NPU Xuhang Electromagnetic Technology Co. Ltd.Xi’an 710100China

As the controlled research of Dynamic Installation(DI)and Static Installation(SI),a new interference installation method was developed based on electromagnetic loading to enhance the mechanical properties of composite *** different interference-fit sizes were considered,ranging from a net fit to 2.0%.The experiments were conducted to evaluate the installation resistance and the mechanical behavior of the joint under external ***,an FFA model to model the stress distribution and damage behavior of the bolt-hole contact interface was *** load-displacement curve and damage modes of experiments were used to verify the FEA *** results show that the installation resistance during DI process was remarkably lower than that of SI process corresponding to all interference-fit sizes,and the stress amplitudes induced by interference were larger and widely *** damage of the hole wall was positively correlated with interference fit size,but DI can significantly reduce the damage compared to *** performance tests,DI enhanced the static bearing capacity and extended longer fatigue life of the joints than *** methods can be an effective way to achieve highly reliable interference joints in composite structures.

关键词： Carbon Fiber-Reinforced Polymer(CFRP) Bolted joints Interference-fit Electromagnetic installation Finite Element Analysis(FEA) Damage mechanics Bearing behavior

Modification of BCC phase and the enhanced reversible hydrogen storage properties of Ti-V-Fe-Mn alloys with varied V/Fe ratios

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China Foundry 2024年第5期21卷 546-554页

作者： Xiang-feng Ma Xin Ding En-lai Liu Rui-run Chen Xin-xiu wang Yong Zhang and Jing-jie guo National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266500ShandongChina AECC Harbin Dongan Engine Co.Ltd.Harbin 150001China

Ti-V-based alloys are proved of huge potential in storing hydrogen,but the incomplete reversible hydrogen storage capacity caused by overstability of V hydride has limited the large-scale *** this study,Ti_(32)V_(40+x)Fe_(23-x)Mn_(5)(x=0,4,8,12,at.%)alloys were designed,and the effects of V/Fe ratio on phase constitution and hydrogen storage properties were *** main phase of the alloys is body-centered cubic(BCC)phase,and the lattice constants of the BCC phase decrease with the decrease of V/Fe ***,C14 Laves phase exists in alloys with a Fe content of 19at.%to 23at.%.For hydrogenation,the C14 Laves phase can accelerate the hydrogen absorption rate,but the hydrogen absorption capacity is *** the decrease of V/Fe ratio,the hydride gradually *** to its large lattice constant and high hydrogen absorption phase content,the Ti_(32)V_(52)Fe_(11)Mn_(5)alloy shows the most enhanced hydrogen storage properties with hydrogenation and dehydrogenation capacities of 3.588wt.%at 298 K and 1.688wt.%at 343 K,*** hydrogen absorption capacity of this alloy can be reserved to 3.574wt.%after 20 cycles of hydrogen absorption and desorption.

关键词： hydrogen storage Ti-based alloy lattice constant BCC phase

Integrated multi-scale approach combining global homogenization and local refinement for multi-field analysis of high-temperature superconducting composite magnets

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 747-762页

作者： Hanxiao guo Peifeng GAO Xingzhe wang Key Laboratory of Mechanics on Western Disaster and Environment of Ministry of Education Key Laboratory of Special Function Materials and Structure Design of Ministry of EducationCollege of Civil Engineering and MechanicsLanzhou UniversityLanzhou 730000China

Second-generation high-temperature superconducting(HTS)conductors,specifically rare earth-barium-copper-oxide(REBCO)coated conductor(CC)tapes,are promising candidates for high-energy and high-field superconducting *** respect to epoxy-impregnated REBCO composite magnets that comprise multilayer components,the thermomechanical characteristics of each component differ considerably under extremely low temperatures and strong electromagnetic *** numerical models include homogenized orthotropic models,which simplify overall field calculation but miss detailed multi-physics aspects,and full refinement(FR)ones that are thorough but computationally ***,we propose an extended multi-scale approach for analyzing the multi-field characteristics of an epoxy-impregnated composite magnet assembled by HTS pancake *** approach combines a global homogenization(GH)scheme based on the homogenized electromagnetic T-A model,a method for solving Maxwell's equations for superconducting materials based on the current vector potential T and the magnetic field vector potential A,and a homogenized orthotropic thermoelastic model to assess the electromagnetic and thermoelastic properties at the macroscopic *** then identify“dangerous regions”at the macroscopic scale and obtain finer details using a local refinement(LR)scheme to capture the responses of each component material in the HTS composite tapes at the mesoscopic *** results of the present GH-LR multi-scale approach agree well with those of the FR scheme and the experimental data in the literature,indicating that the present approach is accurate and *** proposed GH-LR multi-scale approach can serve as a valuable tool for evaluating the risk of failure in large-scale HTS composite magnets.

关键词： epoxy-impregnated high-temperature superconducting(HTS)magnet multi-scale method global homogenization(GH) local refinement(LR) multi-field analysis

Dynamic characteristics of multi-span spinning beams with elastic constraints under an axial compressive force

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 295-310页

作者： Xiaodong guo Zhu SU Lifeng wang State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A theoretical model for the multi-span spinning beams with elastic constraints under an axial compressive force is *** displacement and bending angle functions are represented through an improved Fourier series,which ensures the continuity of the derivative at the boundary and enhances the *** exact characteristic equations of the multi-span spinning beams with elastic constraints under an axial compressive force are derived by the Lagrange *** efficiency and accuracy of the present method are validated in comparison with the finite element method(FEM)and other *** effects of the boundary spring stiffness,the number of spans,the spinning velocity,and the axial compressive force on the dynamic characteristics of the multi-span spinning beams are *** results show that the present method can freely simulate any boundary constraints without modifying the solution *** elastic range of linear springs is larger than that of torsion springs,and it is not affected by the number of *** an increase in the axial compressive force,the attenuation rate of the natural frequency of a spinning beam with a large number of spans becomes larger,while the attenuation rate with an elastic boundary is lower than that under a classic simply supported boundary.

关键词： multi-span spinning beam elastic constraint improved Fourier series free vibration semi-analytical solution

Protective eff ect and mechanism of nanoantimicrobial peptide ND-C14 against Streptococcus pneumoniae infection

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World Journal of Emergency Medicine 2024年第1期15卷 28-34页

作者： Yangyang guo Yaqi Sun Hongxia Wu Jian Lu Yuan Lin Jiaqing Zhu Meihong lai Meiqi Zhang Jun wang Jungang Zheng Department of Intensive Care Medicine Hangzhou Traditional Chinese Medicine Hospital Affi liated to Zhejiang Chinese Medical UniversityHangzhou 310021China National Children’s Regional Medical Center National Clinical Research Center for Child HealthChildren’s HospitalZhejiang University School of MedicineHangzhou 310052China Department of Spleen and Stomach Diseases Hangzhou Traditional Chinese Medicine Hospital Affi liated to Zhejiang Chinese Medical UniversityHangzhou 310021China Department of Ultrasonic Medicine the First Affi liated Hospital of Ningbo UniversityNingbo 315010China Department of Anesthesiology the First Affi liated Hospital of Ningbo UniversityNingbo 315010China Zhejiang University School of Medicine Hangzhou 310058China The First People’s Hospital of Yuexi County Yuexi 616650China

BACKGROUND:Streptococcus pneumoniae(***)is a common pathogen that causes bacterial ***,with increasing bacterial resistance,there is an urgent need to develop new drugs to treat *** *** with a 14-carbon saturated fatty acid(ND-C14)is a novel nanoantimicrobial peptide designed by modifying myristic acid at the C-terminus of humanα-defensin 5(HD5)via an amide ***,it is unclear whether ND-C14 is effective against lung infections caused by ***:In vitro,three groups were established,including the control group,and the HD5 and ND-C14 treatment groups.A virtual colony-count assay was used to evaluate the antibacterial activity of HD5 and ND-C14 against *** morphological changes of *** treated with HD5 or ND-C14 were observed by scanning electron *** vivo,mice were divided into sham,vehicle,and ND-C14 treatment *** in the sham group were treated with 25μL of phosphate-buffered saline(PBS).Mice in the vehicle and ND-C14 treatment groups were treated with intratracheal instillation of 25μL of bacterial suspension with 2×108 CFU/mL(total bacterial count:5×10^(6) CFU),and then the mice were given 25μL PBS or intratracheally injected with 25μL of ND-C14(including 20μg or 50μg),*** rates were evaluated in the vehicle and ND-C14 treatment *** burden in the blood and bronchoalveolar lavage fluid were *** lung histology of the mice was assessed.A propidium iodide uptake assay was used to clarify the destructive eff ect of ND-C14 against ***:Compared with HD5,ND-C14 had a better bactericidal eff ect against *** because of its stronger ability to destroy the membrane structure of *** in *** vivo,ND-C14 significantly delayed the death time and improved the survival rate of mice infected with ***-C14 reduced bacterial burden and lung tissue ***,ND-C14 had a membrane per

关键词： Streptococcus pneumoniae Antimicrobial peptides Humanα-defensin 5 Infection

Thermodynamic and experimental study of high-temperature roasting of blast furnace gas ash for recovery of metallic zinc and iron

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Journal of Iron and Steel Research International 2024年第1期31卷 108-120页

作者： Zi-han wang Jing guo Han-jie guo Bin Li School of Metallurgical Engineering University of Science and Technology BeijingBeijing100083China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina

A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in detail by using ther-modynamic equilibrium calculation and the principle of minimum free *** results showed that the main reaction in the system is the reduction of ZnFe_(2)_(4)and iron *** the full temperature range,iron oxides were more easily reduced than zinc *** of the amount of CO contained in the system,the reduction of ZnO to Zn was difficult to proceed below the boiling point(906℃)of *** the reduction temperature is below 906℃,the reduction process of zinc ferrate was ZnFe_(2)_(4)→ZnO;when the reduction temperature is above 906℃,its reduction process becomed ZnFe_(2)_(4)→ZnO→Zn(g).The metallization and dezincification rates of the BFA gradually increased with increasing reaction *** the C/O ratio increased,the metallization and dezincification rates first increased and then *** effect of reduction time on BFA reduction was similar to that of reaction temperature.

关键词： Blast furnace gas ash Thermodynamics Zinc removal Iron reduction High-temperature reduction roasting Integrated utilization