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Advances in Manufacturing 2019年第2期7卷 133-141页

作者： Yun-Song Lian chen-Liang Mu Ming Liu hui-feng chen Bin Yao Department of Mechanical and Electrical Engineering Xiamen University Xiamen 361102 Fujian People's Republic of China

A structural model of a soft/hard compositecoated textured (SHCCT) tool was proposed and substantiated by a three-dimensional numerical simulation. Its dry turning performance as applied to AISI-1045 steel was analyzed via three-factor five-level orthogonal experiments for different coating parameters, including coating thickness, coating material, and thickness ratio of the soft and hard coatings. In addition, the cutting performance of the proposed SHCCT tool was compared with those of uncoated non-textured, coated non?textured, and uncoated textured tools, and its superiority was proved by the significant reductions in the cutting force, and specifically, the cutting temperature. The optimal results were provided by the SHCCT tool with a WS2/ZrN soft/hard composite coating, a 0.9:0.1 thickness ratio of the above ingredients, and a total coating thickness of 0.5 μm.

关键词： Dry cutting performance Soft/hard composite-coated textured (SHCCT) tool Finite element analysis Coating parameters Cemented carbide

Turbulence Modulations in the Boundary Layer of a Horizontal Particle-Laden Channel Flow

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Chinese Physics Letters 2010年第6期27卷 129-132页

作者： LI Jing LIU Zhao-hui WANG Han-feng chen Sheng LIU Ya-Ming HAN Hai-feng ZHENG Chu-Guang State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074

Turbulence modulations are experimentally investigated using particle image velocimetry （PIV） in the lower boundary layer of a fully developed horizontal channel flow. A simultaneous two-phase PIV measurement technique is adopted to acquire the turbulent statistics quantities and to examine the coherent structures in the near-wall region. Polythene beads with diameters of 60 μm are used as dispersed phases, and the PIV measurements have been performed at three mass loadings varying from 2.5 ×10^-4 to 5 × 10^-3. All the experiments are performed at a wall shear Reynolds number of Reτ = 430. The results show that the presence of the particles suppresses the coherent structures, with shorter streamwise extent of the quasistrearnwise structures, and then, the wall-normal velocity fluctuations and shear Reynolds stresses are both decreased in the near-core region. In addition, as a result of the particle wake, the turbulence intensity and shear Reynolds stress both increase in the vicinity of the wall. Due to the drag effects of the particles on the gas, the streamwise velocity gradients decrease in the outer region and increase in the viscous sublayer, meanwhile the thickness of the viscous sublayer also decreases. These results cause the peak values of the streamwise velocity fluctuations adjacent to the wall to increase, and the peak positions shift to the wall. This is the reason for decreasing the near-wall region and increasing the near-core region of the streamwise velocity fluctuations in appearance.

关键词： Reynolds stress Wakes Flow in channels Turbulence intensities Statistical analysis Drag

The mechanisms of pH regulation on promoting volatile fatty acids production from kitchen waste

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Journal of Environmental Sciences 2025年第1期147卷 414-423页

作者： feng Liu Tingting Wang Leiyu feng Yinguang chen College of Environmental Science and Engineering Tongji UniversityShanghai 200092China TUS-Environmental Science and Technology Development Co. Ltd.Beijing 100084China

The anaerobic acid production experiments were conducted with the pretreated kitchen waste under pH *** results showed that pH 8 was considered to be the most suitable condition for acid production,especially for the formation of acetic acid and propionic *** average value of total volatile fatty acid at pH 8 was 8814 mg COD/L,1.5 times of that under blank *** average yield of acetic acid and propionic acid was 3302 mg COD/L and 2891 mg COD/L,*** activities of key functional enzymes such as phosphotransacetylase,acetokinase,oxaloacetate transcarboxylase and succinylcoA transferase were all *** further explore the regulatory mechanisms within the system,the distribution of microorganisms at different levels in the fermentation system was obtained by microbial sequencing,results indicating that the relative abundances of Clostridiales,Bacteroidales,Chloroflexi,Clostridium,Bacteroidetes and Propionibacteriales,which were great contributors for the hydrolysis and acidification,increased rapidly at pH 8 compared with the blank ***,the proportion of genes encoding key enzymes was generally increased,which further verified the mechanism of hydrolytic acidification and acetic acid production of organic matter under pH regulation.

关键词： Kitchen waste Acid fermentation Volatile fatty acids pH regulation Functional genes

Effect of graphene addition on activation and kinetic properties of La-Mg-Ni-based hydrogen storage alloys

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Journal of Iron and Steel Research International 2025年第1期32卷 227-238页

作者： Dian-chen feng Chun-ling Zheng Zhi-yuan Zhao Dong-sheng Zhou hui-ping Ren Yang-huan Zhang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina Department of Functional Material Research China Iron and Steel Research Institute GroupBeijing100081China

The La_(1.7)Pr_(0.3)Mg_(16)Ni hydrogen storage alloy was prepared by medium-frequency induction melting,and then the composite hydrogen storage alloy powder of La_(1.7)Pr_(0.3)Mg_(16)Ni+x wt.%(x=0,2,4,and 6)graphene was prepared by ball milling for 10 *** effect of the addition of graphene on the activation and hydrogen de/absorption properties of La_(1.7)Pr_(0.3)Mg_(16)Ni alloy was *** result demonstrated that these composite alloys were composed of La_(2)Mg_(17),La_(2)Ni_(3),and Mg_(2)Ni *** saturated hydrogen absorption,it was composed of LaH_(3),Mg_(2)NiH_(4),and MgH_(2)phases,while during the dehydrogenation process,it was composed of LaH_(3),Mg,and Mg_(2)Ni *** addition of graphene can help get a more homogeneous granule after ball milling and accelerate the first activation of dehydrogenation/hydrogen *** hydrogen release activation energy of the alloys first decreases and then increases as the graphene content increases from x=0 wt.%to x=6 wt.%.The minimum activation energy of the composite hydrogen storage alloy is 51.22 kJ mol^(-1) when x=4 wt.%.

关键词： La-Mg-Ni alloy Graphene Mechanical ball milling Activation property Dynamic performance

Modular assembly of Co4-thiacalix[4]arene units and Keggin-type SiW12O40 for visible-light photothermal conversion

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Tungsten 2025年第1期7卷 112-119页

作者： Jia-hui Li Qing Zhao Dong-Ao Mao Kun Zhou Bao-Kuan chen Yan-feng Bi School of Petrochemical Engineering Liaoning Petrochemical University

The construction of metal-organic coordination clusters（MCCs） using modular secondary building units is an important method for preparing functional *** this study,two new MCCs modularly assembled from Keggin-type {SiW12O40}H4TC4A=p-tert-Butylthiacalix[4]arene(SiW12) units and thiacalixarene-supported Co4-thiacalix[4]arene(Co4-TC4A polynuclear second-building units（PSBUs,H4TC4A=p-tert-Butylthiacalix[4]arene） are *** two MCCs,abbreviated as Co4-SiW12and Co8-SiW12,were structurally characterized by single-crystal X-ray *** Co4-SiW12is a supramolecular structure involving cation-anion interactions between Co4-TC4A PSBUs and ***8-SiW12features "barbell-like" shapes with two Co4-TC4A coordinatively linked to a Keggin-type SiW12unit on opposite via W-O_t-Co *** coordination of Co4-TC4A to SiW12in Co8-SiW12resulted in significantly improved photothermal conversion performances compared with Co4-SiW12and pure SiW12or ***-gap determination and photophysical analysis combined with density functional theory calculations indicated the binding mode between Co4-TC4A PSBUs and SiW12,which considerably influences the way of electron transport and the conversion ability of visible light to heat.

关键词： Modular construction Photothermal conversion Polyoxometalate Thiacalixarene

Characteristics of catalytic destruction of dichloromethane and ethyl acetate mixture over HxPO4-RuOx/CeO2 catalyst

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Journal of Environmental Sciences 2025年第2期148卷 336-349页

作者： Jiawen chen Qingjie Meng feng Bi Jingkun chen Xiaole Weng Zhongbiao Wu Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China School of Civil&Environmental Engineering and Geography Science Ningbo UniversityNingbo 315211China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 311200China Zhejiang Provincial Engineering Research Centre of Industrial Boiler&Furnace Flue Gas Pollution Control Hangzhou 310058China

Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds(VOCs)originating fromsolvent-based industrial *** varied composition tends to influence each VOC’s catalytic behavior in the reaction *** investigated the catalytic destruction of multi-component VOCs including dichloromethane(DCM)and ethyl acetate(EA),as representatives from pharmaceutical waste gases,over co-supported HxPO_(4)-RuOx/CeO_(2) catalyst.A mutual inhibitory effect relating to concentrations because of competitive adsorption was verified in the binary VOCs oxidation and EA posed a more negative effect on DCM oxidation owing to EA’s superior adsorption *** adsorption of EA on acidic sites(HxPO_(4)/CeO_(2))promoted DCM activation on basic sites(O^(2−))and the dominating EA oxidation blocked DCM’s access to oxidation centers(RuOx/CeO_(2)),resulting in boosted monochloromethane yield and increased chlorine deposition for DCM *** impaired redox ability of Ru species owing to chlorine deposition in turn jeopardized deep oxidation of EA and its by-products,leading to increased gaseous by-products such as acetic acid originating fromEA ***,DCM at low concentration slightly promoted EA conversion at low temperatures with or without water,consistent with the enhanced EA adsorption in co-adsorption *** was mainly due to that DCM impeded the shielding effect of hydrolysate deposition from rapid EA hydrolysis depending on the decreased ***,water benefited EA hydrolysis but decreased CO_(2) selectivity while the generated water derived from EA was likely to affect DCM *** work may provide theoretical guidance for the promotion of applied catalysts toward industrial applications.

关键词： Catalytic destruction Multi-component VOCs Mixture effect Interaction mechanism

Correlation between grain size,mechanical properties and deformed microstructure of Fe-20Mn-6Al-0.6C-0.15Si low-density steel

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Journal of Iron and Steel Research International 2025年第1期32卷 282-292页

作者： Qi Zhang Guang-hui chen Zheng-liang Xue Zheng-kun chen Guang Xu State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina Red Eagle Novel Refractory Materials Research Institute Zhejiang Red Eagle Group Co.Ltd.Huzhou313000ZhejiangChina

The effects of austenite grain size on the deformed microstructure and mechanical properties of an Fe-20Mn-6Al-0.6C-0.15Si(wt.%)low-density steel were *** microstructure of the experimental steel after solution treatment was single austenitic *** austenite grain size increased with solution temperature and time.A model was established to show the relationship between temperature,time and austenite grain size for the experimental *** addition,as the solution temperature increased,the strength decreased,while the elongation first increased and then *** decrease in elongation after solution treatment at 1100℃ for 90 min is contributed to the over-coarse austenite ***,after solution treatment at 900℃ for 90 min,the strength-elongation product reached the highest value of 44.4 GPa%.As the austenite grain size increased,the intensity of//tensile direction fiber *** was accompanied by a decrease in dislocation density,resulting in a lower fraction of low-angle grain boundaries and a lower work hardening ***,the austenite grain size has a critical influence on the mechanical properties of the low-density *** grains lead to a lower yield strength due to the Hall-Petch effect and a lower tensile strength because of lower dislocation strengthening.

关键词： Austenitic low-density steel Solution treatment Grain size Mechanical property Deformed microstructure

Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw

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Green Energy & Environment 2025年第1期10卷 161-172页

作者： Meng-Ying Liu Zhe-hui Zhang Xue-Qi Wang Qian Sun chen Zhang Yu Li Zhuohua Sun Katalin Barta feng Peng Tong-Qi Yuan State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural

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Post-tunable salt gel electrolytes toward flexible supercapacitor switches

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Journal of Energy Chemistry 2025年第1期100卷 114-124页

作者： hui Wang Shuang chen Xuming Liu Qin Zhang Xin Liu Polymeric and Soft Materials Laboratory School of Chemistry and Life Science and Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012JilinChina Polymeric and Soft Materials Laboratory School of Chemical Engineering and Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012JilinChina

Convertible hydrogel supercapacitors have emerged as promising energy storage devices in switches,diodes,and ***,inherent weaknesses in ionic conductivity,mechanical properties,and water retention of hydrogel electrolytes seriously hinder their *** by the hardness conversion of sea cucumber skin,a conductivity and mechanics dual-tunable salt gel electrolyte is successfully *** salt gel presents a reversible switching of conductors-insulators and a mechanical regulation between softness and hardness via the dissolution-crystallization transition of sodium acetate trihydrate(SAT).Meanwhile,the salt gels spontaneously grow a layer of“armor”through saturated phase-change salt crystals effectively reducing water evaporation of hydrogel ***,this phase-change soft-rigid conversion strategy will expand the capabilities of gel-based flexible supercapacitors(area capacitance:258.6 mF cm^(-2)),and the capacitance retention rate could still reach 86.9%after 3000 cycles at high ***,the salt gel supercapacitor is potentially used in over-heat alarm *** is anticipated that the strategy of conductivity and mechanics of dual-tunable salt gel would provide a new perspective on the development of energy storage devices,wearable electronics,and flexible robots.

关键词： Supercapacitors Salt gels Reversible phase transition Post-tuning Conductivity switching

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A supramolecular formulation of icariin@sulfonatoazocalixarene for hypoxia-targeted osteoarthritis therapy

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Chinese Chemical Letters 2025年第1期36卷 267-271页

作者： Chao Zhang Ai-feng Liu Shihui Li Fang-Yuan chen Jun-Tao Zhang Fang-Xing Zeng hui-Chuan feng Ping Wang Wen-Chao Geng Chuan-Rui Ma Dong-Sheng Guo Orthopedics department First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300380China Orthopedics department National Clinical Research Center for Chinese Medicine Acupuncture and MoxibustionTianjin 300380China College of Chemistry State Key Laboratory of Elemento-Organic ChemistryKey Laboratory of Functional Polymer Materials(Ministry of Education)Frontiers Science Center for New Organic MatterCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300071China

Osteoarthritis(OA)is the most prevalent joint disease and icariin is a promising drug for its ***,the clinical use of icariin is hindered by poor water solubility,low bioavailability,and nonspecific release and biological ***,sulfonated azocalix[4]arene(SAC4A)with enhanced water solubility,recognition capacity,and designed responsiveness was used to improve the efficiency of icariin for OA ***4A,a macrocycle with well-defined molecular weight and structure,could encapsulate and enhance water solubility of various *** addition,SAC4A enables hypoxia-responsive release of loaded *** with icariin treatment,supramolecular complex icariin@SAC4A significantly relieved OA symptoms of rats,including more regular bone morphology and structure,and lower degree of cartilage ***,the supramolecular formulation demonstrated various advantages,including easy preparation,hypoxia-triggered release,and small size that conducive to drug penetration.

关键词： Biomaterial Supramolecular chemistry Calixarene Icariin Osteoarthritis

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