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Continuous generating grinding method for beveloid gears and analysis of grinding characteristics

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Advances in Manufacturing 2022年第3期10卷 459-478页

作者： Bing Cao Guo-Long Li Alessandro Fortunato heng-xin ni College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400030People's Republic of China State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing 400044People's Republic of China Department of Industrial Engineering(DIN) Alma Mater StudiorumUniversity of BolognaViale Risorgimento 2Bologna 40136Italy

Continuous generating grinding has become an important gear processing method owing to its high efficiency and *** this study,an adaptive design model is proposed for the continuous generation of beveloid gears in common gear grinding *** on this model,a method for determining the installation position and grinding kinematics is developed alongside an analytical meshing model for grinding contact trace and derivation of key grinding *** combining these aspects,a general mathematical model for the continuous generation of beveloid gears is presented,comprising the entire grinding process from worm wheel dressing to the evaluation of grinding *** effects of the worm and dressing wheel parameters on the grinding deviation were analysed,facilitating the development of an approach to improve the grinding *** presented procedure represents a novel design method for the continuous generation of beveloid gears in common gear grinding machines,facilitating the appropriate selection of worm and dressing wheel parameters.

关键词： Beveloid gears Continuous generating grinding Meshing model Kinematics model

Radical dehydroxymethylative fluorination of aliphatic primary alcohols and diverse functionalization ofα-fluoroimides via BF_(3)·OEt_(2)-catalyzed C-F bond activation

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Chinese Chemical Letters 2025年第1期36卷 239-243页

作者： Peng Wang Jianjun Wang ni Song xin Zhou Ming Li Molecular Synthesis Center Key Laboratory of Marine MedicineChinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China

Ag_(2)CO_(3)-promoted dehydroxymethylative fluorination of aliphatic alcohols has been achieved with Selectfluor as both oxidant and fluorine *** reaction involvesβ-fragmentation of primary alkoxy radicals,followed by the fluorination of the resulting C-centered radical *** transformation proceeds under mild reaction conditions and exhibits a broad substrate scope,thus opening up a new entrance to the synthesis of fluorinated constructs includingα-fluoroimides and 1-fluoroalkyl benzoates as well as secondary and tertiary alkyl fluorides like versatile 2-fluoro-2-alkyl 1,3-propandiol *** divergent functionalization of the obtainedα-fluoroimides enables an efficient access to amine derivatives through C-F bond activation under the action of BF_(3)·OEt_(2).

关键词： Dehydroxymethylative fluorination Alkoxy radicals β-Fragmentation Silver catalysis C-F Bond activation

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Exploring economic viable species via assessing a tropic-specific microalgal collection

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Journal of Oceanology and Limnology 2025年第1期43卷 210-218页

作者： Chen MA ni WANG Yi xin Qinhua GAN Wenxu ZHOU Yandu LU State Key Laboratory of Marine Resource Utilization in South China Sea School of Marine Biology and FisheriesHainan UniversityHaikou 570228China Hainan Engineering&Research Center of Marine Bioactives and Bioproducts Haikou 570228China Haikou Innovation Platform for Research&Utilization of Algal Bioresource Hainan UniversityHaikou 570228China Hainan Provincial Key Laboratory of Tropical Hydrobiotechnology Hainan UniversityHaikou 570228China

Locations around the equator provide unique habitats for microalgae presumably with exceptional *** develop microalga-derived product systems,we previously created a(sub)tropical microalgal *** this study,two Chlorella strains(MEM176 and MEM193),adaptive to typical tropical climate,were isolated from the *** production performance was evaluated where both strains showed a robust growth in high temperatures and light ***,the strains MEM176 and MEM193 produced 503.6-mg/(L·d)and 411.3-mg/(L·d)biomass,respectively,with high contents of *** commercial and nutritional values were emphasized by amino acid compositions(e.g.,proline,valine,and phenylalanine).Particularly,higher amounts of proline were revealed in MEM176(47.9 mg/g dry biomass(DW))and MEM193(47.9 and 59.2 mg/g DW)than available commercial *** with MEM193,MEM176 produced 129.7%more lipids in which unsaturated fatty acids(particularly linoleic acid andα-linolenic acid)account for 65%of the total ***,it is promising to explore the potential of these Chlorella strains as food additives via outdoor cultivation in tropical area,notably MEM176 that exhibits superiority as sources of essential amino acids and valuable fatty acids.

关键词： Chlorella tropical species food additive microalga

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Positive effect of Mo on mechanical properties of a ni-42W-10Co-xMo medium heavy alloy

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China Foundry 2025年第1期22卷 108-116页

作者： Guo-xin Cao Jian-xin Dong Yong-sheng He He Jiang Fang Hao Zhi-hua nie Teng-fei Ma Bao-quan Fu School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi'an Superalloy Technology Co. Ltd.Xi’an 710299China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou 324000ZhejiangChina

In this study,a novel ni-W-Co-Mo medium heavy alloy(MHA)was designed to improve its mechanical strength via Mo *** the ni-42W-10Co-x Mo alloy series,where x represents the weight percent of Mo and varies between 0,1,2,5,and 10,the microstructure transitions from a dendritic structure to a hypo-eutectic structure as the Mo content increases from 0 to 5wt.%.Moreover,as the Mo content increases from 0 to 10wt.%,the distribution of theμ-phase shifts from being individually dispersed to forming aggregates,and its volume fraction rises from 0.5%to 7.9%.Notably,theμ-phase evolves into an eutectic microstructure,which helps in minimizing the segregation of *** change is accompanied by a substantial enhancement in mechanical properties;specifically,the compressive yield strength at room temperature increases from 350 MPa to 646 MPa,indicating a significant 85%***,the microhardness increases from 230 HV to 304 *** dynamics simulations further reveal that the strengthening mechanism of ni-42W-10Co-x Mo alloys is Mo-induced solid solution strengthening and precipitation strengthening.

关键词： medium-heavy alloys ni-based alloy mechanical properties solid solution strengthening precipitation strengthening

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Fabrication of ni-Zn spinel ferrite with superior magnetic performance from electric arc furnace dust and iron scale

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Journal of Iron and Steel Research International 2025年第1期32卷 105-114页

作者： Yang Li Wei-zhe Jie Chang Chen Yi Su Wu Zhou Hua Zhang Hong-wei ni The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina The Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina

The ni-ZnFe_(2)O_(4)(nixZn_(1-x)Fe_(2)O_(4),x=0.4-0.7)spinel was synthesized using Zn2+extracted from electric arc furnace dust(EAFD),nickel chloride hexahydrate,and Fe^(3+)extracted from iron scale as raw *** zinc was selectively extracted from EAFD using CaO roasting followed by NH_(4)Cl solution *** ferric ion was leached from iron scale using HCl solution as acid *** experimental results demonstrate a high level of efficiency in the extraction of zinc,with a rate of 97.5%,and the leaching rate of ferric ion is 96.89%.The composition of the leaching solution is primary zinc and iron with low calcium,which is beneficial to the preparation of spinel *** influence of ni content(x)and calcination temperature on the synthesis and magnetic properties of nixZn_(1-x)Fe_(2)O_(4)compounds was investigated by X-ray diffraction,scanning electron microscopy,and vibrating sample *** results revealed that both ni content and calcination temperature significantly affect the synthesis and magnetic properties of spinel nixZn_(1-x)Fe_(2)O_(4).Under the conditions of ni content set at x=0.6,calcination temperature of 1100℃,and a duration of 2 h,a spinel nixZn_(1-x)Fe_(2)O_(4)with high saturation magnetization(Ms=65.7 A m2 kg-1)and low coercivity(Hc=0.056 A m^(-1))was obtained.

关键词： Electric furnace arc dust Iron scale Spinel ferrite Magnetic performance Calcination temperature

MOF-derived ni3Fe/ni/niFe2O4@C for enhanced hydrogen storage performance of MgH2

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Journal of Energy Chemistry 2025年第2期101卷 333-344页

作者： Yangping Chen Bolin Sun Guoqing Zhang Siyuan ni Canbing Li Juxiong Tian Yanrui Zhang xinxi Li School of Materials and Energy Guangdong University of Technology Shen Zhen Source Sensor Technology CO. Ltd Department of Electrical Engineering Shanghai Jiao Tong University China Power Investment xinjiang Energy & Chemical Group Hotan Co.Ltd

Magnesium hydride（MgH2） is an important material for hydrogen（H2） storage and transportation owing to its high capacity and ***,its intrinsic properties have considerably limited its industrial *** this study,the niFe-800 catalyst as metal-organic framework（MOF） derivative was first utilized to promote the intrinsic properties of *** to pure MgH2,which releases1.24 wt% H2in 60 min at 275℃,the MgH2-10 niFe-800 composite releases 5.85 wt% H2in the same *** at a lower temperature of 250℃,the MgH2-10 niFe-800 composite releases 3.57 wt% H2,surpassing the performance of pure MgH2at 275℃.Correspondingly,while pure MgH2absorbs 2.08 wt% H2in60 min at 125℃,the MgH2-10 niFe-800 composite absorbs 5.35 wt% H2in just 1 min,Remarkably,the MgH2-10 niFe-800 composite absorbs 2.27 wt% H2in 60 min at 50℃ and 4.64 wt% H2at 75℃.This indicates that MgH2-10 niFe-800 exhibits optimum performance with excellent kinetics at low ***,the capacity of the MgH2-10 niFe-800 composite remains largely stable after ***,the Mg2ni/Mg2niH4acts as a "hydrogen pump",providing effective diffusion channels that enhance the kinetic process of the composite during ***,Fe0facilitates electron transfer and creates hydrogen diffusion channels and catalytic ***,carbon（C） effectively prevents particle agglomeration and maintains the cyclic stability of the ***,the synergistic effects of Mg2ni/Mg2niH4,Fe0,and C considerably improve the kinetic properties and cycling stability of *** work offers an effective and valuable approach to improving the hydrogen storage efficiency in the commercial application of MgH2.

关键词： Catalysts Hydrogen energy MgH2 MOF derivative Solid state storage

Nucleophilic trifluoromethylation with CF_(3)H/LiHMDS: probing the nucleophilic reactivity of LiCF_(3) species

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Science China Chemistry 2025年第2期68卷 505-512页

作者： Yangfan Liu Xiu Wang Chuanfa ni Jinbo Hu College of Chemistry Central China Normal UniversityWuhan 430079China Key Laboratory of Fluorine and nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

The nucleophilic trifluoromethylation involving trifluoromethyllithium(LiCF_(3))species has been an open question since Haszeldine attempted to prepare LiCF_(3) in ***,LiCF_(3) has been used for electrophilic difluoromethylene transfer processes(via elimination of fluoride ions)since ***,we demonstrated that by using a polar solvent such as dimethylformamide(DMF)or hexamethylphosphoramide(HMPA)as the lithium chelator,the in situ deprotonation of fluoroform(HCF_(3))with lithium hexamethyldisilazide(LiHMDS)could generate a tamed LiCF_(3) species that is sufficiently persistent to undergo nucleophilic trifluoromethylation *** nucleophilic reactivity of LiCF_(3) species was probed with several electrophiles,including arylsulfonyl fluorides,diaryl ketones,and silyl *** synthetic utility of this method is demonstrated with the efficient synthesis of highly valuable triflones that are otherwise difficult to synthesize from HCF_(3) using potassium or sodium *** work not only showcases a new protocol for the utilization of fluoroform(an industrial waste with high global warming potential)as the trifluoromethylation reagent,but also provides intriguing insights into the harnessing of nucleophilic reactivity of the transient LiCF_(3) species.

关键词： nucleophilic trifluoromethylation trifluoromethy llithium fluorinated carbanion negative fluorine effect fluorinated carbenoid

Anatomic characteristics of the lacrimal sac and adjacent bony structures–a computed tomographicdacryocystography research

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 251-257页

作者： xin-Han Cui Yan-Wen Fang Li-Min Zhang Ji-ni Qiu Chao-Ran Zhang Yan Wang Eye Institute and Department of Ophthalmology Eye and ENT Hospital of Fudan UniversityShanghai 200031China NHC Key laboratory of Myopia and Related Eye Diseases Key Laboratory of Myopia and Related Eye DiseasesChinese Academy of Medical SciencesShanghai 200031China Shanghai Key Laboratory of Visual Impairment and Restoration Shanghai 200031China Department of Ophthalmology Children’s Hospital of KaifengKaifeng 475000Henan ProvinceChina

AIM:To describe the anatomic characteristics of the lacrimal sac and its adjacent bone structures and to provide surgical recommendations for endoscopic dacryocystorhinostomy(EN-DCR).METHODS:This retrospective comparative study involved 118 sides with complete nasolacrimal duct obstruction and 83 unaffected sides from 126 *** tomographic-dacryocystography(CT-DCG)scans were performed before lacrimal surgery,and image reconstruction was used to obtain continuous 0.75-mm axial,coronal,and segmental sections for *** morphology of the lacrimal sac and its relationship with adjacent bony structures were determined for measurement,as well as the obstructed ***:The height of the lacrimal sac was 12.99±2.10 mm in this *** operculum of the middle turbinate(OMT)was located vertically in the lower third of the lacrimal ***,the junction between the maxillary bone and the lacrimal bone(MB-LB)was close to,mostly(60.2%)posterior to,the lacrimal *** uncinate process was more frequently attached to the lacrimal bones(75.1%).The obstructions were generally located around the entrance of the nasolacrimal duct(NLD).However,some were placed higher,with 7.63%blocked not lower than the *** was a negative correlation between the diameter of the lacrimal sac and the level of obstruction(r=-0.35,Pning before surgery.

关键词： lacrimal sac nasolacrimal duct obstruction endoscopic dacryocystorhinostomy computed tomographic-dacryocystography

Effects of Ti-and Nb-based transition element from single to multiple compound oxides and carbon-based composite additives on Mg-MgH2 hydrogen storage material

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Tungsten 2025年第1期7卷 32-49页

作者： Li-Rong Xiao Chen Chen Shuo Wang Zi-Yin Dai Hideo Kimura Cui ni Chuan-xin Hou Xue-Qin Sun Si-Jie Guo Wei Du Xiu-Bo Xie School of Environmental and Material Engineering Yantai University Bosch HUAYU Steering Systems (Yantai) Co. Ltd.Ytp/MFE University of Tennessee Knoxville Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of Aeronautics

MgH2is considered as a promising hydrogen storage material for its high hydrogen storage capacity,low cost and abundant resource ***,the low kinetics and high enthalpy formation of MgH2limit its wide *** the perspective of adding catalysts to enhance the hydrogen storage properties of Mg-MgH2,this article elaborated the main catalysts based on Ti and Nb transition elements,including single oxide catalysts,binary oxides catalysts（combined with ni,Na,Sr,V,etc.）,multiple catalysts bound to carbon,and composite catalysts with Ti and Nb elements combined with MXene ***,the main pathways of various catalysts to reduce the reaction activity and broaden the hydrogen desorption channel were also *** Ti-based catalysts can enhance the reactive sites of the matrix by forming multivalent states,while Nb-based catalysts broaden the hydrogen reaction channels by forming tiny *** improving the size structure and enhancing the grain size stability,combined with carbon materials should be the future considerations.

关键词： Catalysts Mg-based hydrogen storage alloys Solid hydrogen storage Transition metal elements