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复杂条件下铁路超高边坡石方深孔台阶爆破施工技术

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工程建设与设计 2024年第2期 182-184页

作者：梁宏彦中铁二十局集团第二工程有限公司西安710000

结合某铁路超高边坡爆破施工工程,阐述深孔台阶爆破技术的技术特点和施工工艺流程,并从爆破施工参数、钻孔作业、装药、堵塞、爆破网路敷设、爆破防护、设置警戒、起爆及爆破检查等环节对深孔台阶爆破施工技术操作要点进行详细分析。

关键词：深孔台阶爆破爆破振动控制爆破

维普期刊数据库博看期刊

Deviating from the nanorod shape： Shape-dependent plasmonic properties of silver nanorice and nanocarrot structures

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Frontiers of physics 2016年第2期11卷 45-55页

作者： hong-yan liang hong Wei hong-Xing Xu Center for Nanoscience and Nanotechnology School of Physics and Technology and Institute for Advanced Studies Wuhan University Wuhan 430072 China Institute of Physics Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics Beijing 100190 China

Noble metallic nanostructures exhibit special optical properties resulting from excitation of surface plasmons. Among the various metallic nanostructures, nanorods have attracted particular attention because of their unique and intriguing shape-dependent plasmonic properties. Nanorods can sup- port transverse and longitudinal plasmon modes, the latter ones depending strongly on the aspect ratio of the nanorod. These modes can be routinely tuned from the visible to the near-infrared spectral regions. Although nanorods have been investigated extensively, there are few studies de- voted to nanostructures deviating from the nanorod shape. This review provides an overview of recent progress in the development of two kinds of novel quasi-one-dimensional silver nanostruc- tures, nanorice and nanocarrot, including their syntheses, crystalline characterizations, plasmonic property analyses, and performance in plasmonic sensing applications.

关键词： electron energy loss spectroscopy (EELS) localized surface plasmon resonance (LSPR),multipolar longitudinal plasmon mode nanocarrot nanorice plasmonic sensing

Evaluation on elevated-temperature stability of modified 718-type alloys with varied phase configurations

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International Journal of Minerals,Metallurgy and Materials 2020年第8期27卷 1123-1132页

作者： Zhan Qiao Chong Li hong-jun Zhang hong-yan liang Yong-chang Liu Yong Zhang State Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science&EngineeringTianjin UniversityTianjin 300354China Key Laboratory of the Ministry of Education for Modern Metallurgy Technology North China University of Science and TechnologyTangshan 063210China Science and Technology on Advanced High Temperature Structural Materials Laboratory AEEC Beijing Institute of Aeronautical MaterialsBeijing 100095China

Inconel 718 is a Ni–Fe-based superalloy widely used in aerospace engines because of its excellent mechanical ***,the inferior stability of theγ″phase limits the application of Inconel 718,which coarsens rapidly at temperatures greater than 650°*** improving the temperature tolerance of Inconel 718 requires optimization of the phase configuration via modification of the alloy’s chemical *** the aforementioned objective,this work was conducted to study the precipitation behavior and thermal stability of the strengthening phases with various structures in modified Inconel 718 alloys by tailoring the Al/Ti *** increasing Al/Ti ratio,three particle configurations were formed:γ′/γ″composite,isolatedγ′,andγ′/γ″/γ′composite *** results of aging tests demonstrate that the isolatedγ′and theγ′/γ″/γ′composite structure exhibited better thermal stability at temperature as high as 800°*** isolatedγ′exhibited a reduced coarsening rate compared with theγ′/γ″/γ′composite particles because the isolatedγ′phase was rich in Al,Ti,and ***,theγ′/γ″composite particles coarsened and decomposed rapidly during aging at temperatures greater than 700°C because of the lower stability resulting from the larger number ofγ″*** obtained results provide necessary data for the compositional optimization of novel 718-type alloys.

关键词： Inconel 718 structure thermal stability interface

Scalable synthesis of nanoporous high entropy alloys for electrocatalytic oxygen evolution

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Rare Metals 2022年第1期41卷 125-131页

作者： Li-Hua Liu Ning Li Mei Han Jing-Rui Han hong-yan liang College of Innovation&Entrepreneurship Shanghai Jianqiao UniversityShanghai 201306China School of Materials Science and Engineering Tianjin UniversityTianjin 300350China

High entropy alloys(HEAs)containing five or more equimolar components have shown promising catalytic performance due to their unique chemical and mechanical ***,it is still challenging to prepare scalable and efficient nanoporous HEAs as ***,we present a facile strategy to synthesize largescale nanoporous HEAs particles by combing vacuum induction melting,gas atomization,and acidic etching *** application of HEAs to energy conversion is evaluated with electrocatalytic oxygen evolution reaction(OER)on AlCrCuFeNi *** HEAs exhibit a low OER overpotential of 270 mV to achieve a current density of 10 mA·cm^(-2),a small Tafel slope of 77.5 mV·dec^(-1),and long-term stability for over 35 h in 1 mol·L^(-1) KOH,which is comparable to the state-of-the-art OER electrocatalyst *** findings in this paper not only provide an industrial approach to produce nanoporous HEAs powder but also inspire the applications of HEAs as catalysts.

关键词： High entropy alloys Gas atomization Acidic etching Nanoporous AlCrFeNiCu structures Oxygen evolution reaction

Processing of a low-costγ-γ'NiPtAl coating with improved oxidation resistance

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Rare Metals 2024年第6期43卷 2832-2841页

作者： yan Jiang liang-liang Wei Jian He hong-Bo Guo School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature Structural Materials and Protective Coatings Ministry of Industry and Information TechnologyBeihang UniversityBeijing 100191China

A novelγ-γ'(Ni solid solution—Ni_(3)Al)NiPtAl coating was produced on advanced single-crystal(SC)superalloy N5 by electroplating of a thin Pt coating with~3μm in thickness followed by heat treatment at 1000℃in *** comparison,a traditionalγ-γ'NiPtAl coating was also produced by electroplating of a thick Pt coating with~6μm in thickness followed by heat treatment at 1100℃in *** novel coating has a mass gain of~0.5 mg·cm^(-2)after 100 h 1-h cyclic oxidation at 1150℃,showing better oxidation resistance than the traditional *** oxide scale mostly consisting ofα-Al_(2)O_(3)grew on the novel coating because the element Cr from the SC alloy substrate contributes to the formation ofα-Al_(2)O_(3).Pt content in the novel coating has significant effect on the oxidation *** optimized Pt content in the coating is about 16 at%,which is helpful to reduce the diffusion of harmful elements from the substrate into the coating but also to reduce the cost of the coating.

关键词： γ-γ'NiPtAl coating Platinum Oxidation Al_(2)O_(3) Superalloy

Chemical abundances of three new Ba stars from the Keck/HIRES spectra

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Research in Astronomy and Astrophysics 2021年第11期21卷 67-78页

作者： Shuai Liu liang Wang Jian-Rong Shi Zhen-Yu Wu hong-liang yan Qi Gao Chun-Qian Li CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyChinese Academy of SciencesNanjing 210042China

Based on high resolution,high signal-to-noise(S/N)ratio spectra from Keck/HIRES,we have determined abundances of 20 elements for 18 Ba *** parameter space of these stars is in the range of 4880≤Teff≤6050 K,2.56≤log g≤4.53 dex and-0.27≤[Fe/H]≤0.09 *** is found that four of them can be identified as Ba stars with[s/Fe]>0.25 dex(s:Sr,Y,Zr,Ba,La,Ce and Nd),and three of them are newly discovered,which include two Ba giants(HD 16178 and HD 22233)and one Ba subgiant(HD 2946).Our results show that the abundances ofα,odd and iron-peak elements(O,Na,Mg,Al,Si,Ca,Sc,Ti,Mn,Ni and Cu)for our program stars are similar to those of the thin disk,while the distribution of[hs/ls](hs:Ba,La,Ce and Nd,ls:Sr,Y and Zr)ratios of our Ba stars is similar to those of the known Ba *** of the four Ba stars show clear enhancement in carbon including the known CH subgiant HD *** is found that three of the Ba stars present clear evidence of hosting stellar or sub-stellar companions from the radial velocity data.

关键词： Galaxy Ba stars Chemical abundances Binary

Research on Bast Fiber Extracted from the White Bark of Three Species in the Genus Broussonetia

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Chinese Journal of Polymer Science 2024年第6期42卷 729-738页

作者： Shan-Shan Jin Si-Nong Wang yan-yan Huang Jing-Yu Zhang Peng Liu Hui Yu hong-Dong Zhang Yu-liang yang Institute for Preservation and Conservation of Chinese Ancient Books Fudan University LibraryFudan UniversityShanghai200433China State key laboratory of Molecular Engineering of polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China

Against the backdrop of a global paper resource shortage,there is a growing need to identify fast-growing tree species capable of producing long-lasting *** plant species namely Broussonetia kazinoki,Broussonetia papyrifera and hybrid paper mulberry,belong to the Broussonetia genus,were collected from China to study their white bark suitability for pulp and *** chemical composition revealed that the holocellulose content in Broussonetia kazinoki and Broussonetia papyrifera was more than 80%.The molecular weight distribution of several holocellulose/α-cellulose is observed by GPC,which allows us to better observe the changes of various components on the molecular *** yield,lignin,whiteness,and molecular weight of the pulps obtained by NaOH treatment were *** microscope was used to characterize the fiber length-width ratio and ***,the improvement of the fiber rigidity method based on the Kratky-Porod chain model makes it more theoretical and further reveals the influencing factors of fiber *** study demonstrates the high potentiality of these three species for papermaking applications.

关键词： Broussonetia genus Cellulose Alkaline pulping Kratky-Porod chain model Fiber rigidity

Recognition and rejection of foreign eggs of different colors in Barn Swallows

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Avian Research 2024年第3期15卷 374-378页

作者： Kui yan Wei liang Ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou571158China

Brood parasitic birds lay eggs in the nests of other birds,and the parasitized hosts can reduce the cost of raising unrelated offspring through the recognition of parasitic *** can adopt vision-based cognitive mechanisms to recognize foreign eggs by comparing the colors of foreign and host ***,there is currently no uniform conclusion as to whether this comparison involves the single or multiple threshold decision *** this study,we tested both hypotheses by adding model eggs of different colors to the nests of Barn Swallows(Hirundo rustica)of two geographical populations breeding in Hainan and Heilongjiang Provinces in *** showed that Barn Swallows rejected more white model eggs(moderate mimetic to their own eggs)and blue model eggs(highly non-mimetic eggs with shorter reflectance spectrum)than red model eggs(highly nonmimetic eggs with longer reflectance spectrum).There was no difference in the rejection rate of model eggs between the two populations of Barn Swallows,and clutch size was not a factor affecting egg *** results are consistent with the single rejection threshold *** study provides strong experimental evidence that the color of model eggs can has an important effect on egg recognition in Barn Swallows,opening up new avenues to uncover the evolution of cuckoo egg mimicry and explore the cognitive mechanisms underlying the visual recognition of foreign eggs by hosts.

关键词： Barn Swallow Egg color Hirundo rustica Multiple rejection threshold Single rejection threshold Visual recognition system

Joint Design of ISAC Waveform Under PAPR Constraints

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China Communications 2024年第7期21卷 186-211页

作者： Chen Yating Wen Cai Huang yan liang Le Li Jie Zhang Hui hong Wei State Key Lab of Millimeter Waves Southeast UniversityNanjing 211100China School of Information Science and Technology Northwest UniversityXi’an 710127China National Mobile Communications Research Laboratory Nanjing 211100China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211100China

In this paper,we formulate the precoding problem of integrated sensing and communication(ISAC)waveform as a non-convex quadratically constrained quadratic programming(QCQP),in which the weighted sum of communication multi-user interference(MUI)and the gap between dual-use waveform and ideal radar waveform is minimized with peak-toaverage power ratio(PAPR)*** propose an efficient algorithm based on alternating direction method of multipliers(ADMM),which is able to decouple multiple variables and provide a closed-form solution for each *** addition,to improve the sensing performance in both spatial and temporal domains,we propose a new criteria to design the ideal radar waveform,in which the beam pattern is made similar to the ideal one and the integrated sidelobe level of the ambiguity function in each target direction is minimized in the region of *** limited memory Broyden-Fletcher-Goldfarb-Shanno(LBFGS)algorithm is applied to the design of the ideal radar waveform which works as a reference in the design of the dual-function *** results indicate that the designed dual-function waveform is capable of offering good communication quality of service(QoS)and sensing performance.

关键词： ambiguity function integrated sensing and communication MIMO OFDM PAPR waveform design