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Multi-Physics Coupled Acoustic-Mechanics Analysis and Synergetic Optimization for a Twin-Fluid Atomization Nozzle

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 204-223页

作者： Wenying li Yanying li Yingjie Lu Jinhuan Xu Bo Chen li Zhang Yanbiao li College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Materials Science and Engineering Northwestern Polytechnical UniversityXian 710072China Guizhou Anda Aviation Forging Co. Ltd.Anshun 561005China

Fine particulate matter produced during the rapid industrialization over the past decades can cause significant harm to human ***-fluid atomization technology is an effective means of controlling fine particulate matter *** this paper,the influences of the main parameters on the droplet size,effective atomization range and sound pressure level(SPL)of a twin-fluid nozzle(TFN)are investigated,and in order to improve the atomization performance,a multi-objective synergetic optimization algorithm is presented.A multi-physics coupled acousticmechanics model based on the discrete phase model(DPM),large eddy simulation(LES)model,and Ffowcs Williams-Hawkings(FW-H)model is established,and the numerical simulation results of the multi-physics coupled acoustic-mechanics method are verified via experimental *** on the analysis of the multi-physics coupled acoustic-mechanics numerical simulation results,the effects of the water flow on the characteristics of the atomization flow distribution were obtained.A multi-physics coupled acoustic-mechanics numerical simulation result was employed to establish an orthogonal test database,and a multi-objective synergetic optimization algorithm was adopted to optimize the key parameters of the *** optimal parameters are as follows:A gas flow of 0.94 m^(3)/h,water flow of 0.0237 m^(3)/h,orifice diameter of the self-excited vibrating cavity(SVC)of 1.19 mm,SVC orifice depth of 0.53 mm,distance between SVC and the outlet of nozzle of 5.11 mm,and a nozzle outlet diameter of 3.15 *** droplet particle size in the atomization flow field was significantly reduced,the spray distance improved by 71.56%,and the SPL data at each corresponding measurement point decreased by an average of 38.96%.The conclusions of this study offer a references for future TFN research.

关键词： Twin-fluid nozzle BP neural network Multi-objective optimization Multi-physics coupled Acousticmechanics analysis Genetic algorithm

A Long-Time-Step-Permitting Tracer Transport Model on the Regular Latitude–Longitude Grid

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Advances in Atmospheric Sciences 2024年第3期41卷 493-508页

作者： Jianghao li li DONG Key Laboratory of Earth System Modeling and Prediction China Meteorological AdministrationBeijing 100081China State key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China State Key Laboratory of Severe Weather(LaSW) Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

If an explicit time scheme is used in a numerical model, the size of the integration time step is typically limited by the spatial resolution. This study develops a regular latitude–longitude grid-based global three-dimensional tracer transport model that is computationally stable at large time-step sizes. The tracer model employs a finite-volume flux-form semiLagrangian transport scheme in the horizontal and an adaptively implicit algorithm in the vertical. The horizontal and vertical solvers are coupled via a straightforward operator-splitting technique. Both the finite-volume scheme's onedimensional slope-limiter and the adaptively implicit vertical solver's first-order upwind scheme enforce monotonicity. The tracer model permits a large time-step size and is inherently conservative and monotonic. Idealized advection test cases demonstrate that the three-dimensional transport model performs very well in terms of accuracy, stability, and efficiency. It is possible to use this robust transport model in a global atmospheric dynamical core.

关键词： tracer transport numerical stability latitude–longitude grid

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Meta label associated loss for fine-grained visual recognition

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Science China(Information Sciences) 2024年第6期67卷 230-247页

作者： Yanchao li Fu XIAO Hao li Qun li Shui YU School of Computer Science Nanjing University of Posts and Telecommunications School of Network Engineering Zhoukou Normal University School of Computer Science University of Technology Sydney

Recently, intensive attempts have been made to design robust models for fine-grained visual recognition, most notably are the impressive gains for training with noisy labels by incorporating a reweighting strategy into a meta-learning framework. However, it is limited to up or downweighting the contribution of an instance for label reweighting approaches in the learning process. To solve this issue, a novel noise-tolerant method with auxiliary web data is proposed. Specifically, first, the associations made from embeddings of well-labeled data with those of web data and back at the same class are measured. Next, its association probability is employed as a weighting fusion strategy into angular margin-based loss, which makes the trained model robust to noisy datasets. To reduce the influence of the gap between the well-labeled and noisy web data, a bridge schema is proposed via the corresponding loss that encourages the learned embeddings to be coherent. Lastly, the formulation is encapsulated into the meta-learning framework, which can reduce the overfitting of models and learn the network parameters to be noise-tolerant. Extensive experiments are performed on benchmark datasets, and the results clearly show the superiority of the proposed method over existing state-of-the-art approaches.

关键词： label associated loss weighting noisy samples fine-grained visual recognition noise-tolerant learning meta-learning

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Enrichment of Chemical Element ^(7)li in the Rotating Red Clump Star

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Chinese Physics Letters 2024年第8期41卷 121-125页

作者： Fang-Wen Wu Han-Feng Song Qing-li li Yun He Xin-Yue Qu Zhuo Han College of Physics Guizhou UniversityGuiyang 550025China Geneva Observatory University of GenevaCH-1290 SauvernySwitzerland

About 2 percent of red clump stars are found to be the lithium-rich and thus the surface lithium increases obviously in some red clump *** physical mechanism of the lithium enrichment in these stars has not yet been explained satisfactorily by the evolutionary models of single *** flash induced internal gravity wave mixing(i.e.,IGW)could play a primary role in explaining the red clump star with lithium enrichment and it has a very significant impact on the internal structure and surface compositions of a *** can significantly increase the mixing efficiency of the internal gravity wave because the timescale for the enrichment event has been *** mixing can explain the observed behavior of lithium on red giant stars that are more luminosity than the RGB ***,it has a very small effect on the diffusion of elements because its diffusion coefficient is much smaller than the one of IGW induced mixing after the core helium flash.

关键词： flash stars lithium

日本教育数字化转型探析:以数智时代“人”的培养为中心

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比较教育学报 2024年第3期 35-45页

作者：宋武全李正福张照旭湖州师范学院外国语学院湖州313000 课程教材研究所北京100029 同济大学外国语学院上海200092

日本教育数字化转型秉承以“人”为中心,确立了“技术赋能”的转型路向。通过采取教育数据标准化、建构政产研学协作机制、打造教育数字化全融通平台、筑牢网络信息安全屏障等举措,保障了数智时代“人”的培养生态。通过围绕数字素养打... 详细信息

日本教育数字化转型秉承以“人”为中心,确立了“技术赋能”的转型路向。通过采取教育数据标准化、建构政产研学协作机制、打造教育数字化全融通平台、筑牢网络信息安全屏障等举措,保障了数智时代“人”的培养生态。通过围绕数字素养打造数字化课程并开展数字化教学,助力每一个人差异化全面成材。日本教育数字化转型在定位数智时代“技术”的作用、拓宽教育数字化转型的评价维度、研发以“人”为中心的数字化课程等方面可为我国提供镜鉴。

关键词：日本教育数字化转型以“人”为中心

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li_(2)ZnTi_(3)O_(8)as the host–separator modifier with efficient polysulfides trapping and fast li^(+)diffusion for lithium-sulfur batteries

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Nano Research 2024年第7期17卷 6087-6094页

作者： Mao Qian Yakun Tang Lang liu Yue Zhang Xiaohui li JiaJia Chen State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources Xinjiang UniversityUrumqi 830017China State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005China

The diffusion and loss of lithium polysulfides(liPSs)in lithium-sulfur batteries(LSBs)reduce the sulfur utilization rate and the catalytic conversion efficiency of sulfur species,resulting in early battery ***_(2)ZnTi_(3)O_(8)(LZTO),characterized by its stable spinel structure,exhibits high li+conductivity and holds great potential as an effective adsorbent for *** study proposes a collaborative design concept of LZTO host–separator modifier,which offers a complementary and matching approach in the cathode side,effectively addressing the challenges associated with dissolution and inadequate conversion of *** functional theory(DFT)calculation substantiates the pronounced chemical affinity of LZTO towards *** importantly,the high efficiency ion transport channels are achieved in separator coating due to the presence of the LZTO ***,the catalytic efficacy of LZTO is validated through meticulous analysis of symmetric batteries and Tafel ***,the LZTO host–separator modifier-based cell displays satisfactory rate capability(1449 and 1166 mAh·g^(−1)at 0.1 and 0.5 C)and an impressively capacity(606 mAh·g^(−1)after 500 cycles at 1 C).The coordinated strategy of host–separator modifier is supposed to have wide applications in LSBs.

关键词： li_(2)ZnTi_(3)O_(8) lithium-sulfur batteries host-separator modifier catalytic conversion diffusion and loss of liPSs

Challenges in li-ion battery high-voltage technology and recent advances in high-voltage electrolytes

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Journal of Energy Chemistry 2024年第4期91卷 73-98页

作者： Jianguo liu Baohui li Jinghang Cao Xiao Xing Gan Cui Shandong Key Laboratory of Oil&Gas Storage and Transportation Safety College of Pipeline and Civil EngineeringChina University of Petroleum(East China)Qingdao 266580ShandongChina

The electrolyte directly contacts the essential parts of a lithium-ion battery,and as a result,the electrochemical properties of the electrolyte have a significant impact on the voltage platform,charge discharge capacity,energy density,service life,and rate discharge *** raising the voltage at the charge/discharge plateau,the energy density of the battery is ***,this causes transition metal dissolution,irreversible phase changes of the cathode active material,and parasitic electrolyte oxidation *** article presents an overview of these concerns to provide a clear explanation of the issues involved in the development of electrolytes for high-voltage lithium-ion ***,solidstate electrolytes enable various applications and will likely have an impact on the development of batteries with high energy *** is necessary to improve the high-voltage performance of electrolytes by creating solvents with high thermal stabilities and high voltage resistance and additives with superior film forming performance,multifunctional capabilities,and stable lithium *** offer suggestions for the future development of high-energy lithium-ion batteries,we conclude by offering our own opinions and insights on the current development of lithium-ion batteries.

关键词： lithium-ion battery High voltage Electrolyte additive Solid electrolyte

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A li_(3)P nanoparticle dispersion strengthened ultrathin li metal electrode for high energy density rechargeable batteries

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Nano Research 2024年第5期17卷 4031-4038页

作者： lin Fu Xiancheng Wang Bao Zhang Zihe Chen Yuanjian li Yongming Sun Provincial Guizhou Key Laboratory of Green Chemical and Clean Energy Technology School of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore Institute of Materials Research and Engineering Agency for Science Technology and Research(A*STAR)Singapore 138634Singapore

Achievement of lithium(li)metal anode with thin thickness(e.g.,≤30µm)is highly desirable for rechargeable high energy density ***,the fabrication and application of such thin li metal foil electrode remain challenging due to the poor mechanical processibility and inferior electrochemical performance of metallic ***,mechanico-chemical synthesis of robust ultrathin li/li_(3)P(LLP)composite foils(~15µm)is demonstrated by employing repeated mechanical rolling/stacking operations using red P and metallic li as raw *** in-situ formed li+-conductive li_(3)P nanoparticles in metallic li matrix and their tight bonding strengthen the mechanical durability and enable the successful fabrication of free-standing ultrathin li metal composite ***,it also reduces the electrochemical li nucleation barrier and homogenizes li plating/stripping *** matching to high-voltage liCoO_(2),the full cell with a low negative/positive(N/P)capacity ratio of~1.5 offers a high energy density of~522 W·h·kg^(-1) at 0.5 C based on the mass of cathode and *** into account its facile manufacturing,potentially low cost,and good electrochemical performance,we believe that such an ultrathin composite li metal foil design with nanoparticle-dispersion-strengthened mechanism may boost the development of high energy density li metal batteries.

关键词： lithium metal anode high energy density battery mechanico-chemical synthesis ultrathin li/li_(3)P composite foil low negative/positive capacity ratio

Nonreciprocal generation of Schrodinger cat state induced by topology

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 23-30页

作者： Zi-Hao li li-li Zheng Ying Wu Xin-You Lü School of Physics and Institute for Quantum Science and Engineering Huazhong University of Science and Technologyand Wuhan Institute of Quantum TechnologyWuhan 430074China Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education Jianghan UniversityWuhan 430074China

The Schrodinger cat state produced differently in two directions is anticipated to be a critical quantum resource in quantum information *** exploring the interplay between quantum nonreciprocity and topology in a one-dimensional microcavity array,we obtain the Schrodinger cat state(a pure quantum state)in a chosen direction at the edge cavity,whereas a classical state in the other *** nonreciprocal generation of the cat state originates from the topologically protected chiralitymode excitation in the nontrivial phase,but in the trivial phase,the nonreciprocal generation of cat state ***,our proposal is switchable by tuning the parameters so that a topological phase transition ***,the obtained cat state has nonreciprocal high fidelity,nonclassicality,and quantum coherence,which are sufficient to be used in various one-way quantum technologies,e.g.,invisible quantum sensing,noise-tolerant quantum computing,and chiral quantum *** work provides a general approach to control quantum nonreciprocities with the topological effect,which substantially broadens the fields of nonreciprocal photonics and topological physics.

关键词： Schr?dinger cat state nonreciprocity topology

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