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Effect of the silicon powder content on the properties of Al2.3-SiC-Me composites

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中国科学:技术科学 2010年第4期 460-460页

作者： zhang zhihui 1,{2. guozhi 1 & chen yunbo 1,2.1 school of material science and Engineering,shandong university of science and technology,qingdao 2.6510,china 2.Institute of material Engineering,china Academy of Machinery science and technology,Beijing 100083,china

By means of transient plastic phase process,the Al2.3-SiC-Me composites were produced throungh adding metal aluminium and silicon-powder to Al2.3-SiC *** the condition of the same content of silicon and aluminium mixed-powder,the effect of silicon powder addition on properties of Al2.3-SiC-Me composites was studied by means of XRD and EPMA analyses in the temperature range of 300°C-1600°*** results indicated that the content of metal phase in the sample at 1600°C increases with increasing silicon powder *** the same time,when the temperature is lower than 1100°C,the strength of samples gradually increases with increasing *** when the temperature is higher than 11000°C,the strength of samples gradually decreases with increasing temperature,and this change is very *** results also indicated that at the same sintering temperature,the sample with 6%silicon powder has the maximum strength.

关键词： composites strength ceramic

Preparation of microencapsulatedα-olefin drag reducing polymer used in oil pipeline transportation

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Petroleum science 2011年第1期8卷 99-107页

作者： Li Bing Xing Wenguo Dong Guilin chen Xiangjun Zhou Ningning Qin Zhanbo zhang Changqiao school of Chemistry and Chemical Engineering Shandong UniversityShandong 250061China Linyi Institute of Product Quality Supervision and Inspection Shandong 276004China shandong Institute of Metrology Shandong 250014China shandong Quality Certification Centre Shandong 250014China

Microcapsules containing oil drag-reducing polymer particles were prepared by melting-scattering and condensing of polyethylene wax,in-situ polymerization of urea and formaldehyde,and interfacial polymerization of styrene *** related processes were studied by a molecular dynamics simulation method,and molecular design of microcapsule isolation agent was carried out on the basis of the *** technologies for preparing microencapsulated oil drag-reducing polymer particles were compared and the circulation drag reducing efficiency of the microencapsulated polymer particles was evaluated based on the characterization results and their dissolution *** design of a microcapsule isolation agent suggests that a-olefin polymer particles can be stably dispersed in water by using long-chain alkyl sodium salt surfactant which can prevent the agglomeration ofα-olefin polymer *** results of simulation of the adsorption process shows that the amount of alkyl sodium salt surfactant can directly affect the stability of microencapsulatedα-olefin polymer particles, and there must be a minimum critical amount of *** characterization of the morphology by Scanning Electron Microscopy（SEM） and comparison of the static pressure stability,especially the conditions of reaction and technological control of microcapsules with different shell materials,microencapsulation of a-olefin polymer particles with poly-（urea-formaldehyde） as shell material was selected as the optimum scheme,because it can react under mild conditions and its technological process can be controlled in a large *** relationship of drag reducing rate and dissolving time of microcapsules showed that the formation of microcapsules did not affect the maximum drag reducing rate,and the drag reducing rate of each sample can reach about 35%along with the dissolving time,*** did not affect the drag reducing property ofα-olefin polymer.

关键词： α-olefin polymer molecular design coating material microcapsule preparation stability and solubility drag reducing property

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d-d Orbital coupling induced by crystal-phase engineering assists acetonitrile electroreduction to ethylamine

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Journal of Energy Chemistry 2024年第2期89卷 216-225,I0006页

作者： Honggang Huang Yao chen Hui Fu Cun chen Hanjun Li Zhe {2. Feili Lai Shuxing Bai Nan {2. Tianxi Liu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122JiangsuChina Department of Chemistry KU LeuvenCelestijnenlaan 200FLeuven 3001Belgium College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071ShandongChina

The d-d orbital coupling induced by crystal-phase engineering can effectively adjust the electronic structure of electrocatalysts,thus showing significant catalytic performance,while it has been rarely explored in electrochemical acetonitrile reduction reaction(ARR)to ***,we successfully realize the structural transformation of Pd Cu metallic aerogels(MAs)from face-centered cubic(FCC)to body-centered cubic(BCC)through annealing ***,the BCC Pd Cu MAs exhibit excellent ARR performance with high ethylamine selectivity of 90.91%,Faradaic efficiency of 88.60%,yield rate of 316.0 mmol h^(-1)g^(-1)_(Pd+Cu)and long-term stability for consecutive electrolysis within 2. h at-0.55 V *** hydrogen electrode,outperforming than those of FCC Pd Cu *** the membrane electrode assembly system,BCC Pd Cu MAs also demonstrate excellent ethylamine yield rate of 389.5 mmol h^(-1)g^(-1)_(Pd+Cu).Density functional theory calculation reveals that the d-d orbital coupling in BCC Pd Cu MAs results in an evident correlation effect for the interaction of Pd and Cu sites,which boosts up the Cu sites electronic activities to enhance ARR *** work opens a new route to develop efficient ARR electrocatalysts from the perspective of crystalline structure transformation.

关键词： d-d Orbital coupling Crystal-phase engineering Metallic aerogels Acetonitrile electroreduction reaction Ethylamine

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Efficient ammonia production over e_(g)-occupancy-optimized perovskite electrocatalysts

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Nano Research 2024年第6期17卷 4682-4686页

作者： Mingfa chen Yu zhang Fulong Liu Zhenbao zhang Yuming Dong Yongfa Zhu Heqing Jiang Jiawei Zhu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China qingdao Institute of Bioenergy and Bioprocess technology Chinese Academy of SciencesQingdao 266101China school of Chemistry and Chemical Engineering Linyi UniversityLinyi 276005China Department of Chemistry Tsinghua UniversityBeijing 100084China

Renewable-energy-driven nitrate(NO_(3)^(−))electroreduction to ammonia(NH_(3))(NERA)has been an attractive technology for decarbonizing NH_(3)production and wastewater *** NERA efficiency requires electrocatalysts that are earth-abundant and show fantastic *** we report a semiempirical activity descriptor of eg occupancy(of surface B-site cations)for identifying inexpensive perovskite oxides with extremely high efficacy toward *** establish the descriptor by systematic investigations of more than 10 perovskite *** investigations demonstrate that their intrinsic NERA activities display a volcano-shaped dependence on eg occupancy and the optimized intrinsic activities are accessible at near-1 eg *** could plausibly be attributed to the favorable overlaps between surface adsorbates and vertically-oriented eg *** importantly,utilizing this descriptor,we predict a highly active,selective,and durable NERA electrocatalyst with a composition of Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2.O_(3−δ)(BSCF).Because of its close-to-1 e_(g)occupancy(i.e.~1.2.,the BSCF features a superior NH_(3)production rate of 0.12.g·h^(−1)·mg_(cat.)^(−1)(Faradaic efficiency of 97.8%)that is at top of the volcano plot,and substantially outperforms most NERA electrocatalysts reported in literature.

关键词： perovskite oxide nitrate electroreduction ammonia electrosynthesis eg occupancy

Composite structure Al_(2.O_(3)/Al_(2.O_(3)-YAG:Ce/YAG ceramics with high color spatial uniformity for white laser lighting

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Journal of Advanced Ceramics 2024年第2期13卷 189-197页

作者： Pengfei Sang Le zhang Jian Kang Mingzhou Li Shiwei chen Peng Yang Bingheng Sun Yang Li Wieslaw Strek Hao chen Jiangsu Key Laboratory of Advanced Laser materials and Devices School of Physics and Electronics EngineeringJiangsu Normal UniversityXuzhou 221116China Jiangsu Xiyi Advanced materials Research Institute of Industrial technology Xuzhou 221400China Xuzhou EAGLED technology Co. Ltd.Xuzhou 221116China Xuzhou Kangna Advanced materials technology Co. Ltd.Xuzhou 221116China Xuzhou Fuchang Electronic technology Co. Ltd.Xuzhou 221116China Shanghai Institute of Optics Fine Mechanics Chinese Academy of SciencesShanghai 201800China school of material {2. and Engineering Shanghai Institute of TechnologyShanghai 201418China State Key Laboratory of Crystal materials Shandong UniversityJinan 250100China Institute of Low Temperature and Structure Research Polish Academy of SciencesWroclaw 50-422Poland

Composite ceramic phosphor(CCP)is a candidate light-conversion material to obtain the high-quality laser lighting *** based on the transmissive configuration model could not simultaneously meet the requirements of angular color uniformity and high thermal *** this study,a novel composite structure ceramic was designed,including Al_(2.O_(3)-YAG:Ce/YAG layered ceramic with a size of 1 mm×1 mm for lighting,and Al_(2.O_(3) ceramic(φ=16.0 mm)was used as the wrapping material due to its outstanding thermal *** prepared ceramics exhibited excellent thermal performance and no yellow ring *** this design,we achieved the match of the intensity distribution of the blue and yellow lights,resulting in a high angular color uniformity of 0.9 with a view angle of±80°.All ceramics showed no luminous saturation phenomenon,even the laser power density was increased up to 47.51 W/mm^(2..A high-brightness white-light source with a luminous flux of 618 lm,a luminous efficiency of 12. lm/W,a CCT of 6615 K,and a CRI of 69.9 was obtained in the transmissive *** particular,the surface temperature of the ceramic was as low as 74.1℃ under a high laser radiation(47.51 W/mm^(2.).These results indicate that Al_(2.O_(3)/Al_(2.O_(3)-YAG:Ce/YAG composite structure ceramic is a promising luminescent material in the high-power laser lighting applications.

关键词： Al_(2.O_(3)/Al_(2.O_(3)-YAG:Ce/YAG angular color uniformity high thermal stability high-power laser lighting

Ultrasonic vibration enabled under-liquid forming of metallic glasses

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science Bulletin 2024年第2期69卷 163-166页

作者： Xin Li Luyao Li Sajad Sohrabi Jia'nan Fu Zhen Li Zhe chen Rongce Sun Yu zhang Jinbiao Huang Heting zhang Jian Zhu Xiangyan chen Kaikai Song Jiang Ma school of Mechanical Electrical&Information EngineeringShandong UniversityWeihai 264209China State Key Laboratory of Radio Frequency Heterogeneous Integration College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen 518055China Shenzhen Research Institute of shandong university Shenzhen 518057China

Advancements in forming technology offer significant advantages for the manufacturing industry,including enhanced efficiency,energy conservation,and improved material utilization[1].However,traditional additive manufacturing[2.,thermoplastic forming[3],and laser cutting[4]encounter challenges when applied in under-liquid environments,mainly due to difficulties in temperature control and heat source provision.

关键词： glasses liquid metallic

Dimensionality-driven metal to Mott insulator transition in two-dimensional 1T-TaSe2

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National science Review 2024年第3期11卷 108-118页

作者： Ning Tian Zhe Huang Bo Gyu Jang Shuaifei Guo Ya-Jun Yan Jingjing Gao Yijun Yu Jinwoong Hwang Cenyao Tang Meixiao Wang Xuan Luo Yu Ping Sun Zhongkai Liu Dong-Lai Feng Xianhui chen Sung-Kwan Mo Minjae Kim Young-Woo Son Dawei Shen Wei ruan Yuanbo {2. State Key Laboratory of Surface Physics New Cornerstone Science Laboratory and Department of PhysicsFudan University Shanghai Qi Zhi Institute Shanghai Research Center for Quantum sciences Institute for Nanoelectronic Devices and Quantum Computing Fudan University zhangjiang Fudan International Innovation Center Fudan University State Key Laboratory of Functional materials for Informatics Shanghai Institute of Microsystem and Information Technology(SIMIT)Chinese Academy of Sciences school of Physical science and {2. ShanghaiTech University Korea Institute for Advanced Study school of Emerging technology and Department of Physics University of Science and Technology of China Advanced Light Source Lawrence Berkeley National Laboratory ShanghaiTech Laboratory for Topological Physics Key Laboratory of materials Physics Institute of Solid State Physics Hefei Institutes of Physical ScienceChinese Academy of Sciences High Magnetic Field Laboratory Hefei Institutes of Physical Science Chinese Academy of Sciences Collaborative Innovation Centre of Advanced Microstructures Nanjing University Department of Physics University of Science and Technology of China and Key Laboratory of Strongly Coupled Quantum Matter Physics Chinese Academy of Sciences National Synchrotron Radiation Laboratory University of Science and Technology of China

Two-dimensional materials represent a major frontier for research into exotic many-body quantum phenomena. In the extreme two-dimensional limit, electron-electron interaction often dominates over other electronic energy scales, leading to strongly correlated effects such as quantum spin liquid and unconventional *** dominance is conventionally attributed to the lack of electron screening in the third dimension. Here, we discover an intriguing metal to Mott insulator transition in 1T-TaSe2.hat defies conventional wisdom. Specifically, we find that dimensionality crossover, instead of reduced screening, drives the transition in atomically thin 1T-TaSe2. A dispersive band crossing the Fermi level is found to be responsible for the bulk metallicity in the material. Reducing the dimensionality,however, effectively quenches the kinetic energy of these initially itinerant electrons, and drives the material into a Mott insulating *** dimensionality-driven metal to Mott insulator transition resolves the long-standing dichotomy between metallic bulk and insulating surface of 1T-TaSe2. Our work further reveals a new pathway for modulating two-dimensional materials that enables exploring strongly correlated systems across uncharted parameter space.

关键词： two-dimensional materials 1T-TaSe2 dimensionality crossover metal to Mott insulator transition

Clathrate structure of YB_(3)C_(3) for high-performance thermoelectrics with superior mechanical properties

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Journal of Materiomics 2024年第4期10卷 783-791页

作者： Yangfan Cui Shuai Duan Xiaojun Wang Qinghang Tang Jinyang Xi Xiaobing Liu Yongsheng zhang Xin chen Laboratory of High Pressure Physics and material science(HPPMS) School of Physics and Physical EngineeringQufu Normal UniversityQufuShandong273165China materials Genome Institute Shanghai UniversityShanghai200444China Advanced Research Institute of Multidisciplinary science Qufu Normal UniversityQufuShandong273165China

Exploring high-performance thermoelectric materials with improved mechanical properties is important for broadening the application scope and the assembly requirement of stable *** work presents an effective strategy to discover hard thermoelectric material by inserting foreign atoms in the rigid covalent *** demonstrate this in boron-carbon clathrate VII structure,showing a promising candidate for highly efficient thermoelectric energy conversion,especially with Y atom filled in the cage,with a peak zT of 0.73 at 1,000 *** ab initio calculations indicate that YB_(3)C_(3) system has low lattice thermal conductivity of 4.5 W/(m·K)at 1,000 K due to the strong rattling of encaged Y *** strongly covalent framework provides highly degenerate band structures consisting of heavy and light electron pockets,which can maintain high carrier mobility arising from small effective mass and thus large group ***,high power factor can be achieved in YB_(3)C_(3) for both electron and hole *** addition,it exhibits well mechanical properties and a Vickers hardness of 2..7 GPa because of the strong covalent boron-carbon *** work provides a novel avenue for the search of high-performance thermoelectric materials with excellent mechanical properties,based on boron-carbon clathrate structure.

关键词： Clathrate structure Thermoelectric performance First-principles calculations Mechanical properties Thermal conductivity

Boosting cycling stability by regulating surface oxygen vacancies of LNMO by rapid calcination

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Nano Research 2024年第4期17卷 2671-2677页

作者： Haoran Jiang Cuihua Zeng Wei Zhu Jiawei Luo Zhedong Liu Jingchao zhang Rui Liu Yunhua Xu Yanan chen Wenbin Hu school of materials {2. and Engineering Tianjin UniversityTianjin 300072China school of materials {2. and Engineering Shandong University of Science and TechnologyQingdao 266590China

Spinel LiNi_(0.5-x)Mn_(1.5+x)O_(4)(LNMO)has attracted intensive interest for lithium-ion battery due to its high voltage and high energy ***,severe capacity fade attributed to unstable surface structure has hampered its *** vacancies(OVs)tend to occur in the surface of the material and lead to surface structure reconstruction,which deteriorates the battery performance during electrochemical ***,we utilize high-temperature-shock(HTS)method to synthesize LNMO materials with fewer surface *** calcination drives lower surface OVs concentration,reducing the content of Mn^(3+)and surface reconstruction layers,which is beneficial to obtain a stable crystal *** LNMO material synthesized by HTS method delivers an initial capacity of 12. mAh·g^(-1) at 0.1 C and capacity retention of 81.6%after 300 cycles at 1 C,and exhibits excellent performance at low temperature.

关键词： ultrafast synthesis oxygen vacancy LiNi_(0.5-x)Mn_(1.5+x)O_(4)(LNMO)cathode high-temperature-shock lithium-ion batteries