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Chinese Journal of Aeronautics 2024年第6期37卷 20-37页

作者： Zhiyu LI Kaiyuan zhang Zhigang LI jun LI Institute of Turbomachinery Xi’an Jiaotong UniversityXi’an 710049China

The mid-passage gap is an inevitable structure in a vane passage due to turbine vanes being manufactured *** coolant from this gap is able to prevent hot mainstream ingression and provide cooling protection for the endwall.A novel idea of enlarging the endwall’s coverage area and reducing the endwall’s thermal load by applying the mid-passage gap with variable surface angles is carried out in this *** endwall’s aerothermal and film cooling performances under four mid-passage gap modes at three typical mass flow ratio conditions are numerically *** indicate that under the traditional mid-passage mode,the coolant flows into the mainstream with a perpendicular incidence angle and can’t stick to the ***,cooling failure occurs,and the endwall’s thermal load is badly *** film cooling level at the suction-side endwall is improved when applying the mid-passage gap of a 45surface angle due to the secondary vortex being *** addition,when applying the mid-passage gap of a 135surface angle,the horseshoe vortex is pushed away,and the coverage area at the pressure-side endwall is enlarged *** best film cooling performance is achieved when the upstream surface angle is 135and the downstream surface angle is 45due to the adiabatic film cooling effectiveness being increased at both the pressure-and suction-side *** the mass flow ratio is 1.5%,the coverage area is enlarged by 43%,and the area-averaged adiabatic film cooling effectiveness is increased by 37%,when compared with those under the traditional mid-passage mode.

关键词： Film cooling Heat transfer Surface angle Mid-passagegap Turbinevane endwall

An artificial intelligence approach for particle transport velocity prediction in horizontal flows

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Particuology 2024年第9期92卷 234-250页

作者： Haoyu Chen Zhiguo Wang Hai Huang jun zhang College of Petroleum Engineering Xi'an Shiyou UniversityXi'an710065China Shaanxi Key Laboratory of Carbon Dioxide Sequestration and Enhanced Oil Recovery Xi'an710065China College of New Energy Xi'an Shiyou UniversityXi'an710065China Engineering Research Center of Smart Energy and Carbon Neutral in Oil&Gas Field Universities of Shaanxi ProvinceChina The Erosion/Corrosion Research Center The University of TulsaOK74104United States

Particle entrainment is an inevitable phenomenon in pipeline systems,especially during the development and extraction phases of oil and gas *** predicting the critical velocity for particle transport is a key focus for implementing effective sand control *** work presents a semi-supervised learning–deep hybrid kernel extreme learning machine(SSL-DHKELM)model for predicting the critical velocity,which integrates multiple machine learning theories including the deep learning approach,which is adept at advanced feature ***,the SSL framework enhances the model's capabilities when data availability is *** improved slime mould algorithm is also employed to optimize the model's *** proposed model has high accuracy on both the sample dataset and out-of-sample *** trained with only 10%of the data,the model's error still did not increase ***,this model achieves superior predictive accuracy compared to existing mechanistic models,demonstrating its impressive performance and robustness.

关键词： Particle transport Critical velocity Deep learning Semi-supervised learning Extreme learning machine

Memristive oscillator to memristive map,energy characteristic

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Science China(Technological Sciences) 2024年第5期67卷 1567-1578页

作者： GUO YiTong MA jun zhang XiaoFeng HU XiKui College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou730050China Department of Physics Lanzhou University of TechnologyLanzhou730050China School of Science Chongqing University of Posts and TelecommunicationsChongqing400065China

Most of nonlinear oscillators composed of capacitive and inductive variables can obtain the Hamilton energy by using the Helmholtz theorem when the models are rewritten in equivalent vector *** energy functions for biophysical neurons can be obtained by applying scale transformation on the physical field energy in their equivalent neural *** dynamical systems often have exact energy functions,while some mathematical models just suggest generic Lyapunov functions,and the energy function is effective to predict mode *** this paper,a memristive oscillator is approached by two kinds of memristor-based nonlinear circuits,and the energy functions are defined to predict the dependence of oscillatory modes on energy *** absence of capacitive variable for capacitor,the physical time t and charge q are converted into dimensionless variables by using combination of resistance and inductance(L,R),e.g.,τ=t×R/*** energy function for each memristive map is proposed by applying the similar weights as energy function for the memristive *** example,energy function for the map is obtained by replacing the variables and parameters of the memristive oscillator with corresponding variables and parameters for the memristive *** memristive map prefers to keep lower average energy than the memristive oscillator,and chaos is generated in a discrete system with two *** scheme is helpful for energy definition in maps,and it provides possible guidance for verifying the reliability of maps by considering the energy characteristic.

关键词： Hamilton energy memristor Helmholtz theorem scale transformation memristive circuit

Experimental Study of Temperature Control Based on Composite Phase Change Materials during Charging and Discharging of Battery

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Journal of Thermal Science 2024年第2期33卷 578-590页

作者： LI Xiaolin WANG jun CAO Wenxiang zhang Xuesong School of Automotive and Traffic Engineering Jiangsu UniversityZhenjiang212013China

This study is to utilize the heat-absorbing and releasing capabilities of phase change materials(PCM)to regulate the surface temperature fluctuations of batteries during charging and *** goal is to keep the battery within the optimal operating temperature *** impact of PCM thickness and phase change temperature on battery temperature is investigated by encircling a cylindrical battery with a PCM *** improve the thermal conductivity of PCM,expanded graphite(EG) is added to make a composite phase change material(CPCM),and the effects of various EG mass ratios on battery surface temperature and CPCM utilization level are *** findings indicate that increasing PCM thickness effectively extends temperature control time,but its impact is *** difference in phase change temperature of PCM controls the battery temperature in different temperature *** phase change temperatures are unsuitable for controlling battery temperature in high temperature *** addition of EG enhances the thermal conductivity of PCM,leading to further control of battery *** results show that the addition of 6%(mass ratio) EG to CPCM extends the effective temperature control time by 11 min and improves by 28% compared to a single *** CPCM utilization is also more satisfactory and achieved a balance between heat storage and thermal conductivity in a battery thermal management system(BTMS) based on PCM.

关键词： phase change material expanded graphite thermal management system effective control time

Impact response and energy absorption of metallic buffer with entangled wire mesh damper

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Defence Technology（防务技术） 2024年第5期35卷 137-150页

作者： Chao Zheng jun Wu Mangong zhang Xin Xue Institute of Metal Rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350116China Wuhan Second Ship Design and Research Institute Wuhan 430205China

An innovative metallic buffer consisting of series-connected hat-shaped entangled wire mesh damper(EWMD)and parallel springs are proposed in this work to enhance the reliability of engineering *** impact response and the energy dissipation mechanism of hat-shaped EWMD under different quasi-static compression deformations(2-7 mm)and impact heights(100-200 mm)are investigated using experimental and numerical *** results demonstrate distinct stages in the quasi-static mechanical characteristics of hat-shaped EWMD,including stiffness softening,negative stiffness,and stiffness *** loss factor gradually increases with increasing compression deformation before entering the stiffness hardening *** impact loads,the hat-shaped EWMD exhibits optimal impact energy absorption when it enters the negative stiffness stage(150 mm),resulting in the best impact isolation effect of metallic ***,the impact energy absorption significantly decreases when hat-shaped EWMD enters the stiffness hardening ***,quasi-static compression analysis after experiencing different impact loads reveals the disappearance of the negative stiffness ***,with increasing impact loads,the stiffness hardening point progressively shifts to an earlier stage.

关键词： Metallic buffer Hat-shaped EWMD Drop impact Energy absorption characteristics Mechanical behavior

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数据要素市场培育的制约因素及其突破路径

改革 2023年第9期 21-33页

作者：刘雅君张雅俊吉林省社会科学院中国社会科学院大学商学院

数字经济时代,数据因有别于传统生产要素的技术—经济特征而成为现代生产要素。培育数据要素市场需要实现数据要素市场化配置、畅通数据要素交易流通和充分释放数据要素价值三重构建目标。中国数据要素市场发展迅速,市场建设有序推进,... 详细信息

数字经济时代,数据因有别于传统生产要素的技术—经济特征而成为现代生产要素。培育数据要素市场需要实现数据要素市场化配置、畅通数据要素交易流通和充分释放数据要素价值三重构建目标。中国数据要素市场发展迅速,市场建设有序推进,但基础制度仍不完善,尚未充分挖掘数据要素市场规模并释放发展潜力。当前面临着数据安全保护不足、开放共享流通不畅、数据权属不清、双重信任困境难规避、定价和交易体系不健全等现实挑战和制约因素。破解数据要素市场化困局,未来应基于“制度支撑—交易体系—市场监管—技术赋能”四位一体的发展路径,以数据要素分类分级为起点,通过数据要素确权、定价和参与收入分配的机制等制度基础支撑数据要素有效供给;加快数据要素市场交易体系构建;推动科学立法与规范监管,保障和支撑数据要素市场交易及运行。培育数据要素市场,应加速推动要素市场化配置,充分释放数据要素价值,赋能数字中国建设。

关键词：数据要素数据要素市场数字经济

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10CrNiMo高强钢的低周疲劳特性

北京科技大学学报 2011年第1期33卷 22-27页

作者：张亚军洛阳船舶材料研究所洛阳471039

采用圆形横截面光滑试样,通过轴向不同应变幅控制的低周疲劳试验,研究了10CrNiMo高强钢的低周疲劳特性,包括循环应力-应变行为、应变-寿命特点、循环应力响应及其力学滞后现象,给出了相应的疲劳参数、循环软硬化特性及应变滞后规律.对... 详细信息

采用圆形横截面光滑试样,通过轴向不同应变幅控制的低周疲劳试验,研究了10CrNiMo高强钢的低周疲劳特性,包括循环应力-应变行为、应变-寿命特点、循环应力响应及其力学滞后现象,给出了相应的疲劳参数、循环软硬化特性及应变滞后规律.对裂纹扩展方向及试样疲劳断口的观察表明:裂纹扩展面与轴向力呈现多角度关系,裂纹萌生于试样表面,沿断口周边分布,且具有多源性;疲劳裂纹主要以锐化--钝化机制扩展.

关键词：高强钢低周疲劳疲劳性能断口

pH Induced Self-assembly of AIE Fluorescent Probe for Tumor Imaging

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Chinese Journal of Polymer Science 2024年第1期42卷 7-13,I0005页

作者： Jing-Yuan Xiang Wen-Long zhang He-Ting Li ya-Ning He Department of Chemical Engineering Key Laboratory of Advanced Materials(MOE)Tsinghua UniversityBejing 100084China

This work reported an AIE fluorescent probe for tumor imaging based on the p H induced self-assembly strategy. The fluorescent probe was composed of an acid-responsive soluble copolymer PEG-b-PAMA-DMMA with a maleic acid amide group and an anionic soluble aggregation-induced emission fluorogen(AIEgen) TPE-2SO_(3)^(-). The polymer could be transformed into a protonated amine-containing polymer after the hydrolysis of maleic acid amide in acidic tumor microenvironment, which would be further self-assembled with TPE-2SO_(3)^(-)to form aggregated nanoparticles. The transition of TPE-2SO_(3)^(-)from dispersed state to aggregated state led to an obvious increase in fluorescence intensity due to its AIE characteristics.

关键词： p H-responsive Self-assembly Fluorescent probe AIE Tumor imaging

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慢性血栓栓塞性肺动脉高压患者的麻醉管理

中国实用内科杂志 2023年第1期43卷 14-19页

作者：张亚军中日友好医院手术麻醉科北京100029

慢性血栓栓塞性肺动脉高压(CTEPH)是急性肺血栓栓塞后幸存者最严重的并发症,亦是惟一一种可通过肺动脉内膜切除手术(PEA)治愈的肺动脉高压类型。由于严重的肺动脉高压与右心功能不全,CTEPH患者的麻醉极具挑战。手术前多学科的讨论与充... 详细信息

慢性血栓栓塞性肺动脉高压(CTEPH)是急性肺血栓栓塞后幸存者最严重的并发症,亦是惟一一种可通过肺动脉内膜切除手术(PEA)治愈的肺动脉高压类型。由于严重的肺动脉高压与右心功能不全,CTEPH患者的麻醉极具挑战。手术前多学科的讨论与充分的麻醉前评估至关重要。患者从清醒到体外循环转机阶段的麻醉总则是维持右心室-肺动脉的偶联。体外循环转机及深低温停循环阶段的麻醉总则是均匀降温、复温以及脑、心等重要器官的保护。体外循环脱机至离开手术室阶段的麻醉总则是恢复左心室泵功能与防治肺缺血再灌注损伤。文章围绕CTEPH患者病理生理的特殊性以及PEA手术特点,根据手术步骤对麻醉评估、右心功能管理、深低温停循环的安全实施、控制性低心排技术的应用以及肺内出血并发症的处理等核心麻醉技术进行总结和讨论。

关键词：麻醉肺动脉高压右心衰竭围手术期管理深低温停循环

A quantum-enhanced magnetometer using a single high-spin nucleus in silicon

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Chinese Physics B 2024年第9期33卷 110-115页

作者： Tao Xin Ke zhang jun Li Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Guangdong Provincial Key Laboratory of Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Physikalisch-Technische Bundesanstalt Bundesallee 10038116 BraunschweigGermany Institute of Quantum Precision Measurement State Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China

Quantum enhanced metrology has the potential to go beyond the standard quantum limit and eventually to the ultimate Heisenberg *** particular,quantum probes prepared in nonclassical coherent states have recently been recognized as a useful resource for ***,there has been considerable interest in constructing magnetic quantum sensors that combine high resolution and high ***,we explore a nanoscale magnetometer with quantum-enhanced sensitivity,based on 123Sb(I=7/2)nuclear spin doped in silicon,that takes advantage of techniques of spin-squeezing and coherent *** the optimal squeezed initial state,the magnetic field sensitivity may be expected to approach 6 aT·Hz^(−1/2)·cm^(−3/2) and 603 nT·Hz^(−1/2) at the single-spin *** magnetic sensor may provide a novel sensitive and high-resolution route to microscopic mapping of magnetic fields as well as other applications.

关键词： quantum magnetometer silicon quantum qubit nuclear electrical resonance