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Numerical simulation on directional solidification and heat treatment processes of turbine blades

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China Foundry 2024年第5期21卷 476-490页

作者： Ye-yuan Hu ju-huai ma.Qing-yan Xu School of ma.erials Science and Engineering Tsinghua UniversityKey Laboratory for Advanced Materials Processing TechnologyMinistry of EducationBeijing 100084China

Study on turbine blades is crucial due to their critical role in ensuring the efficient and reliable operation of aircraft ***-based single crystal superalloys are extensively used in the hot ma.ufacturing of turbine blades due to their exceptional high-temperature mechanical *** hot ma.ufacturing of single crystal blades involves directional solidification and heat *** ma.ufacturing of these blades is time-consuming,capital-intensive,and often insufficient to meet industrial *** simulation techniques have gained widespread acceptance in blade ma.ufacturing research due to their low energy consumption,high efficiency,and rapid turnaround *** article introduces the modeling and simulation of hot ma.ufacturing in single crystal *** discussion outlines the prevalent ma.hema.ical models employed in numerical simulations related to blade hot *** encapsulates the advancements in research concerning ma.ro to micro-level numerical simulation techniques for directional solidification and heat treatment ***,potential future trajectories for the numerical simulation of single crystal blade hot ma.ufacturing are also discussed.

关键词： single crystal blades Ni-based superalloy directional solidification heat treatment numerical simulation

Improved Reall-Santos method for AdS black holes in general 4-derivative gravities

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 74-86页

作者： Peng-ju Hu Liang ma.Hong Lü Yi Pang Center for Joint Quantum Studies and department of Physics School of ScienceTianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Peng Huanwu Center for Fundamental Theory Hefei 230026China

For asymptotically flat black holes,Reall-Santos method is a convenient tool to compute leading higher derivative corrections to the thermodynamic quantities without actually solving the modified field ***,there are subtleties in its generalization to asymptotically AdS black holes with general higher derivative *** of all,it is necessary to know all the higher derivative holographic counterterms and the surface terms implementing the variational principle and subtracting the *** then needs to solve for the modified AdS radius and rescale the time coordinate in an appropriate way such that the induced metric on the conforma. boundary of AdS black hole is not *** observe that Reall-Santos method can be directly applied to a particular 4-derivative gravity model,known as the Einstein-Weyl gravity,which does not modify the AdS radius and requires only the Gibbons-Hawking-York term and holographic counterterms for the 2-derivative *** thus suggest that to compute the thermodynamic quantities of AdS black holes in general 4-derivative theories of gravity,one simply needs to transform it to a Einstein-Weyl gravity with identical thermodynamic variables by appropriate field *** explicitly verify this proposal with spherically-symmetric and static charged black holes in Einstein-ma.well theory extended with generic 4-derivative interactions.

关键词： black holes thermodynamics higher-derivative corrections effective theories higher dimensional black holes quantum gravity

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Multi-scale analyses of phase transforma.ion mechanisms and hardness in linear friction welded Ti17(a+β)/Ti17(β)dissimilar titanium alloy joint

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Chinese Journal of Aeronautics 2024年第1期37卷 312-324页

作者： Zhenguo GUO Tiejun ma.Xiawei YANG ju LI Wenya LI Achilles VAIRIS State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding TechnologiesNorthwestern Polytechnical UniversityXi’an 710072China Aeronautical Key Laboratory for Welding and Joining Technologies AVIC Manufacturing Technology InstituteBeijing 100024China Mechanical Engineering department University of West AtticaAthens 12241Greece

The Ti17(a+β)-Ti17(β)dual alloy-dual property blisk produced using Linear Friction Welding(LFW)is considered as high-performa.ce component in advanced ***,up to now,microstructure evolution and relationship between microstructure and micro mechanical properties of LFWed Ti17(a+β)/Ti17(β)dissimilar joint have not been thoroughly *** this work,complex analyses of the phase transforma.ion mechanisms of the joint are conducted,and phase transforma.ions in individual zones are correlated to their microhardness and *** reveal that a dissolution occurs under high temperatures encountered during LFW,which reduces microhardness of the joint to that of Ti17(a+β)and Ti17(β).In ThermoMechanically Affected Zone of Ti17(a+β)(Tma.-(a+β))side joint,a large number of nanocrystalline a phases form with different *** microstructure strengthens significantly by fine grains which balances partial softening effect of a dissolution,and increases nanohardness of a phase and microhardness of Tma.-(a+β).Superlattice metastableβphase precipitates from metastableβin Weld Zone(WZ)during quick cooling following welding,because of short-range diffusion migration of solute atoms,especiallyβstabilizing elements Mo and *** precipitation of the superlattice metastableβphase results in precipitation strengthening,which in turn increases nanohardness of metastableβand microhardness in WZ.

关键词： Linear friction welding Ti17 titanium alloy Phase transforma.ion Microhardness Nanohardness

Genetic ma.ping of plasma.proteome on brain structure

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Journal of Genetics and Genomics 2024年第7期51卷 774-777页

作者： Shengyi ma.Fengzhe Xu Yuanqing Fu ju-Sheng Zheng Fudan University Shanghai 200433China School of Life Sciences Westlake UniversityHangzhouZhejiang 310030China Westlake Center for Intelligent Proteomics Westlake Laboratory of Life Sciences and BiomedicineHangzhouZhejiang 310030China

The emergence of high-throughput techniques for proteomics measurement has led to an increasing number of proteogenomic studies that aim to reveal protein quantitative trait loci(pQTL)based on large cohorts(Suhre et a... 详细信息

关键词： ma.ping structure throughput

Improving Satellite-Retrieved Cloud Base Height with Ground-Based Cloud Radar Measurements

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Advances in Atmospheric Sciences 2024年第11期41卷 2131-2140页

作者： Zhonghui TAN ju WANG Jianping GUO Chao LIU Miao ZHANG Shuo ma College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration School of Atmospheric PhysicsNanjing University of Information Science&TechnologyNanjing 210044China National Satellite Meteorological Center(National Center for Space Weather) China Meteorological AdministrationBeijing 100081China

Cloud base height(CBH) is a crucial parameter for cloud radiative effect estima.es, clima.e change simulations, and aviation guidance. However, due to the limited informa.ion on cloud vertical structures included in passive satellite radiometer observations, few operational satellite CBH products are currently available. This study presents a new method for retrieving CBH from satellite radiometers. The method first uses the combined measurements of satellite radiometers and ground-based cloud radars to develop a lookup table(LUT) of effective cloud water content(ECWC), representing the vertically varying cloud water content. This LUT allows for the conversion of cloud water path to cloud geometric thickness(CGT), enabling the estima.ion of CBH as the difference between cloud top height and CGT. detailed comparative analysis of CBH estima.es from the state-of-the-art ECWC LUT are conducted against four ground-based millimeter-wave cloud radar(MMCR) measurements, and results show that the mean bias(correlation coefficient) is0.18±1.79 km(0.73), which is lower(higher) than 0.23±2.11 km(0.67) as derived from the combined measurements of satellite radiometers and satellite radar-lidar(i.e., Cloud Sat and CALIPSO). Furthermore, the percentages of the CBH biases within 250 m increase by 5% to 10%, which varies by location. This indicates that the CBH estima.es from our algorithm are more consistent with ground-based MMCR measurements. Therefore, this algorithm shows great potential for further improvement of the CBH retrievals as ground-based MMCR are being increasingly included in global surface meteorological observing networks, and the improved CBH retrievals will contribute to better cloud radiative effect estima.es.

关键词： cloud base height passive radiometer ground-based cloud radar remote sensing

Technical innovation in the “Beishan No. 1” hard rock tunnel boring ma.hine for high-gradient spiral tunnels

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Frontiers of Engineering ma.agement 2024年第1期11卷 175-179页

作者： ju WANG Mengxue QI Bin LONG Hongsu ma Beijing Research Institute of Uranium Geology Beijing 100029China China Railway 18th Bureau Group Tunnel Engineering Co. Ltd.Chongqing 400700China China Railway Construction Heavy Industry Co. Ltd.Changsha 410100China

1 Project overview The“Beishan No.1”,the world’s first-ever hard rock Tunnel Boring ma.hine(TBM)tailored for high-gradient spiral tunnels,constitutes a pivotal element within the Beishan Underground Research Laboratory(URL)initiative in *** URL,the first URL for geological disposal of high level radioactive waste(HLW)in China,is a national key construction project listed in the“13th Five-Year Plan”.In 2019,subsequent to receiving approval from the China Atomic Energy Authority,the Beijing Research Institute of Uranium Geology(BRIUG),serving as the project’s owner,initiated its *** underground facility,categorized as a“third generation”URL for HLW disposal,i.e.,area-specific URL,was located in Beishan,Jiuquan City,Gansu Province,China,following more than three decades of rigorous research on site selection.

关键词： tunnel boring ma.hine extremely hard rock continuous sma.l-radius curves high gradient equipment technology innovation

Hydrogen production from hydrolysis of NaBH_(4) solution over Co-Fe-B@g-C_(3)N_(4)/NF thin film catalyst

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Rare Metals 2024年第6期43卷 2648-2659页

作者： Yan Wang Jia-Xin ma.Jian Ren Di Zhang Feng-Yan Xu Ke Zhang Zhong-Qiu Cao Qiu-ju Sun Guo-de Li Shi-Wei Wu Hong-Hui Chen College of Chemistry and Chemical Engineering Shenyang Normal UniversityShenyang 110034China Experimental Center Shenyang Normal UniversityShenyang 110034China Hunan Shande Energy Storage New ma.erials Research Institute Limited Company Changde 415000China

In this study,the double loaded Co-Fe-B@g-C_(3)N_(4)/NF(NF:Ni foam)thin film catalysts were prepared for the first time via chemical deposition method at room *** optimizing the reducing agent concentration to 0.9 mol·L^(-1),the as-obtained Co-Fe-B@g-C_(3)N_(4)/NF exhibited the twisted ribbon structure with more distinct three-dimensional hierarchy and the sma.ler particle size,showing the good catalytic property for the hydrolysis of NaBH_(4)*** H_(2)generation rate of Co-Fe-B@g-C_(3)N_(4)/NF and binary Co-B@g-C_(3)N_(4)/NF under visible light irradiation surpassed the value under natural *** apparent activation energy of Co-Fe-B@g-C_(3)N_(4)/NF(45.0 kJ·mol^(-1))under visible light irradiation was obviously reduced when compared with the natural condition(48.4 kJ·mol^(-1))and binary Co-B@g-C_(3)N_(4)/NF(60.6 kJ·mol^(-1))under visible light ***,the catalytic performa.ce of the optimized Co-Fe-B@g-C_(3)N_(4)/NF thin film catalyst was superior to most of the reported non-noble metal and even noble metal ***,it illustrated that the catalytic H_(2)production performa.ce of Co-Fe-B@g-C_(3)N_(4)/NF thin film was distinctly improved after the introduction of light and multicomponent recombination.

关键词： Sodium borohydride Co-Fe-B@g-C_(3)N_(4)/NF catalyst Chemical deposition Hydrogen production

Near-infrared non-fused electron acceptors for efficient organic photovoltaics

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Chinese Chemical Letters 2024年第4期35卷 436-441页

作者： Wenxiang ma.Xinyu He Tianyi Chen de-Li ma.Hongzheng Chen Chang-Zhi Li State Key Laboratory of Silicon and Advanced Semiconductor ma.erials Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

developing narrow-bandgap organic semiconductors is important to facilitate the advancement of organic photovoltaics(OPVs). Herein, two near-infrared non-fused ring acceptors(NIR NFRAs), PTBFTT-F and PTBFTT-Cl have been developed with A-π_A-π_D-D-π_D-π_A-A non-fused structures. It is revealed that the introduction of electron deficient π-bridge(π_A) and multiple intramolecular noncovalent interactions effectively retained the structural planarity and intramolecular charge transfer of NFRAs, extending strong NIR photon absorption up to 950 nm. Further, the chlorinated acceptor, with the enlarged π-surface compared to the fluorinated counterpart, promoted not only molecular stacking in solid, but also the desirable photochemical stability in ambient, which are helpful to thereby improve the exciton and charge dynamics for the corresponding OPVs. Overall, this work provides valuable insights into the design of NIR organic semiconductors.

关键词： Organic photovoltaic Near-infrared Non-fused electron acceptor Noncovalent interaction Stability

Skin-inspired interface modification strategy toward a structurefunction integrated hybrid sma.t fabric system with self-powered sensing property for versatile applications

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Nano Research 2024年第9期17卷 8200-8208页

作者： Xiang Cheng Teng Chen de Gong Pengcheng ma.Bo Chen jun Cai Aerospace Informa.ion Research Institute Chinese Academy of SciencesBeijing 100190China School of Mechanical Engineering and Automa.ion Beihang UniversityBeijing 100191China Beijing U-Precision Tech Co. Ltd.Beijing 100176China University of Chinese Academy of Sciences Beijing 100049China

Fabric-based composites with superior mechanical properties and excellent perceptive function are highly ***,it rema.ns a huge challenge to attain structure-function integration,especially for hybrid fabric ***,a skin-inspired interface modification strategy is proposed toward this target by constructing a hybrid sma.t fabric system consisting of two types of sma.t fabrics:carbon nanotube(CNT)/MXene-modified aramid fabrics and zinc oxide nanorod(ZnO NR)-modified carbon *** on that,flexible piezoelectric pressure sensors with skin-like hierarchical perception interfaces are fabricated,which demonstrate superb sensitivity of 2.39 V·kPa^(-1)and are capable of various wearable monitoring ***,the interface-modified hybrid fabric reinforced plastics can also be fabricated,which are proven to possess 13.6%higher tensile strength,10.1%elastic *** impressively,their average energy absorption can be improved by 111.9%,accompanied with inherent dama.e alert *** offers a paradigm to fabricate structure-function integrated hybrid sma.t fabric composites for the sma.t clothing and intelligent aerial vehicles.

关键词： hybrid fabrics interface modification piezoelectric pressure sensors self-diagnostic composites structure-function integration