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Hydrogen storage properties of(Ti0.85Zr0.15)1.05Mn1.2Cr0.6V0.1M0.1(M=Ni,Fe,Cu) alloys easily activated at room temperature

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Progress in Natural Science:Materials International 2017年第6期27卷 652-657页

作者： peng Liu Xiubo Xie Li Xu Xingguo Li Tong Liu Key Laboratory of Aerospace Materials and Performance (Ministry of Education) School of Materials Science and Engineering Beihang University State Grid Smart Grid Research Institute Future Science and Technology City Changping 3. Beijing National Laboratory for Molecular Sciences (BNLMS) The State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University

The(Ti0.85Zr0.15)1.05Mn1.2Cr0.6V0.1M0.1(M=Ni, Fe, Cu) alloys with a single C14-type Laves phase have been fabricated by arc melting. They are able to be easily activated by one hydrogen absorption and desorption cycle under 4 MPa hydrogen pressure and vacuum at room temperature. Partial substitution of M for Mn results in the increase of hydrogenation and dehydrogenation capacities in an order of Ni < Fe < Cu. M elements increase the absorption and desorption plateau pressure in an order of(Ti0.85Zr0.15)1.05Mn1.2Cr0.6V0.1Cu0.1<(Ti0.85Zr0.15)1.05Mn1.2Cr0.6V0.1Fe0.1<(Ti0.85Zr0.15)1.05Mn1.2Cr0.6V0.1Ni0.1. The(Ti0.85Zr0.15)1.05Mn1.2Cr0.6V0.1Cu0.1alloy has reversible hydrogen capacities of 1.81 wt% at 273 K and 1.58 wt% at 318 K with formation enthalpy(ΔHab) of-20.66 kJ mol-1and decomposition enthalpy(ΔHde) of 27.37 kJ mol-1. The differences in the hydrogen storage properties can be attributed to the increase of the interstitial size for hydrogen accommodation caused by the increase of unit cell volumes in the order of(Ti0.85Zr0.15)1.05Mn1.2Cr0.6V0.1Ni0.1<(Ti0.85Zr0.15)1.05Mn1.2Cr0.6V0.1Fe0.1<(Ti0.85Zr0.15)1.05Mn1.2Cr0.6V0.1Cu0.1.

关键词： Titanium-manganese based alloy Laves phase Unit cell volume Activation properties Hydrogen storage properties

A First-principles Calculation of Structures and Stability of Al_(13)I Cluster

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Chinese Journal of Structural Chemistry 2006年第2期25卷 232-239页

作者： LI Gui-Fa peng Ping YANG Feng HAN Shao-Chang School of Materials Science ＆ Engineering Hunan University Changsha 410082 China

Using first-principles pseudo-potential plane wave method, the energetics, geometrical and electronic structures of three Al13I cluster isomers were calculated. The calculation results of the binding energy indicate Al13I cluster is more stable than Al13 cluster although its electrons are not a magic number as in Alia cluster, and among Al13I cluster isomers the ＂Bridge＂ structure is the most stable, the second is the ＂Ontop＂ structure, and the worst is the ＂Hollow＂ structure. By analyzing the geometrical structures of Al13I cluster isomers, it is found that after I atom and Al13 cluster combine the geometrical structures of Al13 moieties are changed besides Al13I Hollow cluster, in which the Alia moiety is still a regular icosahedron. For Al13I Ontop cluster, the Al13 moiety has a shrinking trend to I, whereas in Al13I Bridge cluster it is distorted. Mulliken population analysis shows for the interaction of electrons between Al-I atoms in Al13I cluster not only there exists an ionic bonding but there is a covalent bonding. Part of electrons in the Alia cluster transfer to I as Al13 cluster and I atom combine. The order of the strength of covalent bonding between Al13 moiety and I in Al13I cluster isomers is Al13IBridge〉Al13IHollow〉Al13I Ontop. Further analysis of electric structures of Al13 and Al13I clusters indicates a higher stability of Al13I cluster than Al13 cluster can be attributed to the s-p hybridization of 3s and 3p electrons of Al in Al13 moiety induced by 1 doped, which leads to fewer electrons N（EF） at EF in Al13I and a larger energy gap △EH-L between HOMO and LUMO levels in Al13I cluster. The distinguish of structural stability of Al13I cluster isomers mainly originates from their different magnitudes .in decrease of N（EF） and increase of △EH-L relative to Al13 cluster. The fewest N（EF） and the largest △EH-L are responsible for the high stability of Al13I Bridge cluster.

关键词： Al13I cluster structural stability electronic structure,pseudo-potential plane-wave method

Behaviour of Hexagon Split Ring Resonators and Left-Handed Metamaterials

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Chinese Physics Letters 2004年第7期21卷 1330-1332页

作者： ZHANGFu-Li ZHAOQian LIUYa-Hong LUOChun-Rong ZHAOXiao-peng InstituteofElectrorheologicalTechnology DepartmentofAppliedPhysicsNorthwesternPolytechnicalUniversityXi'an710072

We used a rectangular waveguide system to measure the X-band (8–12GHz) transmission of hexagon split ring resonators (SRRs) alone and the left-handed metamaterials (LHMs) consisting of hexagon SRR array and wire array. The experimental results show that for an individual SRR, the resonance frequency increases with the azimuthal gap, but decreases with the radial gap. For two identical SRRs, the resonance peak has a shift because of the electromagnetic interaction, and the resonance frequency and the strength decrease with the separation distance. Finally, we demonstrate the left-handed effect of the LHMs.

关键词： Ring gages

A potential giant gallium deposit hosted in the tailing dam of the Fankou Zn-Pb deposit in northern Guangdong Province, South China

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China Geology 2024年第1期7卷 157-160页

作者： peng-peng Yu Zhao-bin Hu Yi Zheng Lan-xuan Guo Shi-yuan Ouyang Gui-qiang Yuan Shang-zhou Chen Cheng-ming Wang Xi Chen School of Earth Sciences and Geological Engineering Sun Yat-sen UniversityGuangzhou 510275China Guangdong Provincial Key Lab of Geological Process and Mineral Resources Survey Sun Yat-sen UniversityGuangzhou 510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Zhongjin Lingnan Nonfemet Co. LtdShenzhen 518000China

*** The Fankou giant zinc(Zn)-lead(Pb)deposit in Guangdong Province is well-known for its huge reserves of over 10 Mt(million ton)Zn+Pb metals and high ore-grade with Zn+Pb exceeding 15%(Guangdong Fankou Deposit Investigation Group,1980;Zhu XY et al.,2017).After 60 years of exploration and exploitation,the deposit has accumulated millions of tons of *** interesting question is that what components are hosted in these tailings,and whether some key and critical metals such as gallium and germanium are extremely enriched and worth further comprehensive *** motivated us to conduct an integrated set of field investigation,sampling,major-trace element analyses and reserve assessments about the Fankou *** this contribution,we discover that the tailings contain a variety of metal elements such as zinc,lead and gallium with comprehensive utilization *** data can act as a scientific guidance for further exploration and utilization of the Fankou tailings,and aid to enhance the utilization efficiency of the key mineral resource in *** study also provide demonstration for future green mine construction in China.

关键词： deposit comprehensive Guangdong

Floor heave mechanism for gob-side entry retaining with concrete blocks and control method:A case study

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Underground Space 2024年第2期15卷 244-259页

作者： Jiong Wang peng Liu Manchao He Guangyuan Yu Huanzhi Tian State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China College of Mining Engineering North China University of Science and TechnologyTangshan 063210China

The issue of significant floor heave deformation in gob-side entry retaining has long been a challenging problem in the context of longwall *** paper studies the floor heave failure mechanism and control method for gob-side entry retaining with concrete blocks in Guizhou Faer Coal Mine in *** on Rankine’s earth pressure theory,the effective shear stress equation for the plastic slip of roadway floor is *** deformation mechanism of floor heave in a retaining roadway with a block wall is revealed in this *** new comprehensive control method is proposed,encompassing roof pre-splitting blasting for pressure relief,reinforcing cables for roof control,double directions control bolts for concrete block,and pliability cushion yielding ***3D numerical calculation model is established,which shows that the new method can effectively reduce the average vertical stress peak value of the entity coal floor by 34.6%and significantly reduce the pressure source causing the roadway floor ***,a multi-parameter real-time online monitoring system for mine pressure was designed,and field tests were carried *** results show that the maximum value of roadway floor heave under the new method is 163 mm,reduced by 66.9%,and the roadway floor heave is effectively *** research findings offer a fresh perspective and new ideas for controlling floor heave in mining operations.

关键词： Gob-side entry retaining Floor heave mechanism Plastic slip Control methods Mine pressure monitoring

A MODIFIED TORSION PENDULUM FOR MEASURING THE SHEAR MODULUS OF A SINGLE MICRO-SIZED FILAMENT

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Acta Mechanica Solida Sinica 2014年第3期27卷 221-233页

作者： Dabiao Liu Yuming He peng Hu Zhipeng Gan Huaming Ding Department of Mechanics Huazhong University of Science and Technology Hubei Key Laboratory of Engineering Structural Analysis and Safety Assessment

A modified torsion pendulum apparatus is developed for measuring the shear modu- lus of single filaments with uniform micro-sized diameter. A single filament fixed at both ends and with a ring-shaped mass attached at the middle is used as a clamped-clamped torsion pendulum. The shear modulus of single filaments can be expressed as a function of the oscillation frequency of the torsion pendulum. The oscillation motion is measured with a CCD laser displacement sensor, and its frequency is determined by the Fast Fourier Transform （FFT） method. The shear moduli of three types of filaments： copper wires, tungsten wires and carbon fibers are accurately measured with this technique. It is found that the size effect in shear moduli of both copper wires and tungsten wires is minor. Finally, the error analysis of our measurement technique is presented in detail.

关键词： torsion pendulum shear modulus size effect single filament

Primary lacrimal sac lymphoma:a case-based retrospective study in a Chinese population

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International Journal of Ophthalmology(English edition) 2023年第4期16卷 532-538页

作者： Fang Bai Hai Tao Xi-Bin zhou Fei Wang peng Wang Li-Hua Wang Hong-Yang Zhang The Lacrimal Center the Senior Department of Ophthalmologythe Third Medical Center of Chinese PLA General HospitalBeijing 100039China

AIM:To determine the clinical characteristics,pathological types,tumor markers,treatments,and outcomes of Chinese patients with primary lacrimal sac ***:This case-based retrospective study analyzed 15 Chinese patients with primary lacrimal sac *** clinical data collected included gender,age at diagnosis,symptoms,imaging examination results,pathologic diagnosis,pathogen identification,tumor markers,treatments,follow-up,and *** statistics were used to characterize the ***-free survival(PFS)was defined as the time from surgery to the last follow-up,first record of tumor recurrence,or ***:There were 7 males and 8 females with unilateral primar y lacrimal sac lymphoma in the lef t eye(n=6)or right eye(n=9).The initial symptom in 13 patients was epiphora,and 2 patients had redness and swelling in the lacrimal sac *** patients ultimately developed epiphora,and 12 had masses in the lacrimal sac *** of preoperative plasma tumor markers indicated 14 patients had elevated homocysteine,9 had elevatedβ2-microglobulin,and 2 had elevated lactate dehydrogenase(LDH);2 patients had elevations of all three markers,and 1 patient had no elevation of any *** patients underwent surgical resection and 12 patients received postoperative *** pathological types were DLBCL(n=8),MALT lymphoma(n=5),and NK/T-cell lymphoma,nasal type(n=2).The mean followup time was 25.8mo(range:4-41)and 2 patients *** patients who underwent mass excision combined with dacryocystorhinostomy(DCR)had no postoperative *** patients who only underwent mass excision had varying degrees of postoperative *** LDH elevation and NK/T-cell lymphoma,nasal type were associated with poor ***:Early diagnosis and treatment can lead to a good prognosis for most patients with primary lacrimal sac *** resection combined with DCR can reduce the occurrence of post-surgical e

关键词： primary lacrimal sac lymphoma pathological type tumor markers treatment and prognosis

Porous a-Al_2O_3 thermal barrier coatings with dispersed Pt particles prepared by cathode plasma electrolytic deposition

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International Journal of Minerals,Metallurgy and Materials 2016年第1期23卷 92-101页

作者： peng Wang Ye-dong He Shun-jie Deng Jin Zhang Beijing Key Laboratory for Corrosion Erosion and Surface Technology University of Science and Technology Beijing

Porous α-Al2O3 thermal barrier coatings （TBCs） containing dispersed Pt particles were prepared by cathode plasma electrolytic deposition （CPED）. The influence of the Pt particles on the microstructure of the coatings and the CPED process were studied. The prepared coatings were mainly composed of α-Al2O3. The average thickness of the coatings was approximately 100 μm. Such single-layer TBCs ex- hibited not only excellent high-temperature cyclic oxidation and spallation resistance, but also good thermal insulation properties. Porous α-Al2O3 TBCs inhibit further oxidation of alloy substrates because of their extremely low oxygen diffusion rate, provide good thermal insu- lation because of their porous structure, and exhibit excellent mechanical properties because of the toughening effect of the Pt particles and because of stress relaxation induced by deformation of the porous structure.

关键词： porous material thermal barrier coatings alumina platinum electrolytic deposition oxidation

Effects of P addition on the microstructure and mechanical properties of Mg–5%Sn–1.25%Si alloy

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 289-294页

作者： Hao-ran Geng Qing-lei Wang peng Liu Ming Wu School of Material Science and Engineering University of Jinan Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials University of Jinan Jinan Jinzhong Electronic Scale Company Ltd.

The effects of Al-P addition on the microstructure and mechanical properties of as-cast Mg–5%Sn–1.25%Si magnesium alloy were investigated. The results show that the phases of the as-cast alloy are composed of α-Mg, Mg2 Sn, Mg2 Si, little P, and AlP. The Chinese character shape Mg2 Si phase changes into a granular morphology by P addition because AlP can act as a heterogeneous nucleation core for the Mg2 Si phase. When 0.225wt% of Al–3.5%P alloy is added, the mechanical properties of the Mg–5%Sn–1.25%Si alloy are greatly improved, and the tensile strength increases from 156 to 191 MPa, an increase of 22.4% compared to the alloy without P addition. When the amount of Al–3.5%P reaches 0.300wt%, a segregation phenomenon occurs in the granular Mg2 Si phase, and the tensile strength and hardness decrease though the elongation increases.

关键词： magnesium alloys microstructure mechanical properties phosphorus