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关键词

薄膜润滑 5

Cu(In 4

Ga)Se₂ 3

超超临界 3

2021全球十大工程成就 2

勘探开发 2

膜分离 2

高含硫 2

2型糖尿病 1

5G；交叉振子；双极化天线；终端天线；超宽带 1

CCS 1

CO₂分离 1

CO₂捕集 1

Ga)Se₂光伏组件 1

HSLC钢 1

Ni–Ti–Cu–V合金 1

PDT 1

Reed-Solomon码；步进式译码算法；超宽带；流水线架构 1

交互式图像分割；多元自适应回归样条；集成学习；薄板样条回归；半监督学习；支持向量回归 1

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Operating characteristic analysis on the ultra-thin low temperature floor-heating system

Hualing ZHANG, Xiaopeng SONG

《结构与土木工程前沿（英文）》 2013年第7卷第2期页码 127-132 doi: 10.1007/s11709-013-0200-3

摘要： Prefabricated ultra-thin radiant heating panel, as a new heating terminal type, is becoming a highlight in Yangtze River Valley area, China recently. However, there is a lack of operating characteristic research in this region, especially the energy consumption and operating mode are even less. To obtain these data, a heating system was set up in a duplex house in Chongqing. The test results show that the floor heating system could almost satisfy thermal comfort requirement at supply water temperature 45°C. But the preheating time was up to 4.5 h which was 1 h longer than that at supply water temperature 50°C. Meanwhile, the energy consumption at supply water temperature 50°C increased 0.10 Nm /h, and the operating efficiency decrease about 2.6% compared to those at water temperature 45°C. Considering both the thermal lag and operating efficiency, a reasonable suggestion was proposed in this paper. That was, the standard families which just stay home at night should adopt the interim mode of partial room with part time. And the supply water temperature should be properly raised during the preheating period and lowered down in the steady heating stage.

关键词： ultra-thin floor heating panel the preheating time thermal comfort energy saving

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A measurement system for thin elastohydrodynamic lubrication films

WANG Xuefeng, GUO Feng, YANG Peiran

《机械工程前沿（英文）》 2007年第2卷第2期页码 193-196 doi: 10.1007/s11465-007-0032-8

摘要： An elastohydrodynamic lubrication (EHL) film measurement system using multi-beam interferometry is introduced in this paper. The measurement principle and the instrumentation are discussed. A simple and efficient method is suggested to obtain the fringe order of measured points. It is demonstrated that the presented measurement system can provide continuous measurement of lubricating films from nano to micro scales at a nano-level resolution, and can be used to investigate ultra-thin EHL films and tiny variations in EHL films.

关键词： instrumentation continuous measurement elastohydrodynamic lubrication ultra-thin measurement

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面向未来低碳道路养护的超薄罩面功能性研究综述 Review

郭猛, 张瑞, 杜修力, 刘鹏飞

《工程（英文）》 2024年第32卷第1期页码 83-99 doi: 10.1016/j.eng.2023.03.020

摘要：

截至2021年，中国公路养护总里程达到525万公里。超薄罩面作为最常用的路面养护技术之一，可以显著提高路面的经济效益和环境效益。为了促进超薄罩面的低碳发展，本文主要研究了超薄罩面几种功能性的作用机理及影响因素。首先，对超薄罩面的抗滑性能、降噪性能、抗车辙性能和抗裂性能进行了评价。结果表明，优质集料可使超薄罩面的抗滑和抗车辙性能提高5 %~20 %。优化后的级配及改性胶结料可将超薄罩面的噪音降低0.4~6.0 dB。高粘度改性胶结料可使超薄罩面混合料的抗车辙性能提高10 %~130 %。玄武岩纤维可使超薄罩面的抗裂性提升20 %以上。由于超薄罩面具有更薄的厚度及更好的道路性能，其基于性能的工程成本与传统罩面相比，可降低30 %~40 %。其次，研究了超薄罩面的几种环保功能，包括融雪除冰、废气降解和路面降温。由于超薄罩面的厚度较薄，有利于氯化物融雪材料向路表的扩散。因此，自融雪超薄罩面的融雪效果较好。此外，含有光催化材料的超薄罩面混合料可以分解20 %~50 %的尾气污染物。彩色超薄罩面最高能够将路面温度降低8.1 ℃。而含有热阻材料的超薄罩面的上下表面温差最高可达12.8 ℃。此外，本文总结了功能型超薄罩面在全世界的一些典型工程应用。本综述有助于研究人员更好地理解超薄罩面的功能性，同时可促进未来多功能低碳道路养护的实现。

关键词：道路养护超薄罩面融雪除冰尾气降解路面降温低碳

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非线性弹性薄膜表面效应的尺寸相关性研究

黄殿武,连媛,李凯

《中国工程科学》 2006年第8卷第4期页码 54-59

摘要：

在Mindlin假设的前提下，考虑了几何非线性条件及表面效应的影响，建立了纳米尺度下尺寸相关的板状各向同性弹性薄膜模型；从哈密尔顿变分原理出发，导出了薄膜的控制方程，用公式明确阐述了由表面张力引起的符合经典板理论且与薄膜变形相关的残余膜力和弯矩；通过微小尺寸薄膜弯曲的算例，说明了表面效应与薄膜厚度的相关性，当薄膜厚度等于或者小于其内禀尺度时，表面效应对薄膜厚度表现出很强的敏感性。

关键词：弹性薄膜几何非线性表面效应内禀尺度尺度相关

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Review of characterization and modeling of polymer electrolyte fuel cell catalyst layer: The blessing and curse of ionomer

Jun HUANG, Zhe LI, Jianbo ZHANG

《能源前沿（英文）》 2017年第11卷第3期页码 334-364 doi: 10.1007/s11708-017-0490-6

摘要： Ionomer impregnation represents a milestone in the evolution of polymer electrolyte fuel cell (PEFC) catalyst layers. Ionomer acts as the binder, facilitates proton transport, and thereby drastically improves catalyst utilization and effectiveness. However, advanced morphological and functional characterizations have revealed that up to 60% of Pt nanoparticles can be trapped in the micropores of carbon support particles. Ionomer clusters and oxygen molecules can hardly enter into micropores, leading to low Pt utilization and effectiveness. Moreover, the ionomer thin-films covering Pt nanoparticles can cause significant mass transport loss especially at high current densities. Ionomer-free ultra-thin catalyst layers (UTCLs) emerge as a promising alternative to reduce Pt loading by improving catalyst utilization and effectiveness, while theoretical issues such as the proton conduction mechanism remain puzzling and practical issues such as the rather narrow operation window remain unsettled. At present, the development of PEFC catalyst layer has come to a crossroads: staying ionomer-impregnated or going ionomer-free. It is always beneficial to look back into the past when coming to a crossroads. This paper addresses the characterization and modeling of both the conventional ionomer-impregnated catalyst layer and the emerging ionomer-free UTCLs, featuring advances in characterizing microscale distributions of Pt particles, ionomer, support particles and unraveling their interactions; advances in fundamental understandings of proton conduction and flooding behaviors in ionomer-free UTCLs; advances in modeling of conventional catalyst layers and especially UTCLs; and discussions on high-impact research topics in characterizing and modeling of catalyst layers.

关键词： polymer electrolyte fuel cell ultra-thin catalyst layer electrostatic interactions characterization and modeling structure-property-performance relation water management

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Fixturing technology and system for thin-walled parts machining: a review

《机械工程前沿（英文）》 2022年第17卷第4期 doi: 10.1007/s11465-022-0711-5

摘要： During the overall processing of thin-walled parts (TWPs), the guaranteed capability of the machining process and quality is determined by fixtures. Therefore, reliable fixtures suitable for the structure and machining process of TWP are essential. In this review, the key role of fixtures in the manufacturing system is initially discussed. The main problems in machining and workholding due to the characteristics of TWP are then analyzed in detail. Afterward, the definition of TWP fixtures is reinterpreted from narrow and broad perspectives. Fixture functions corresponding to the issues of machining and workholding are then clearly stated. Fixture categories are classified systematically according to previous research achievements, and the operation mode, functional characteristics, and structure of each fixture are comprehensively described. The function and execution mode of TWP fixtures are then systematically summarized and analyzed, and the functions of various TWP fixtures are evaluated. Some directions for future research on TWP fixtures technology are also proposed. The main purpose of this review is to provide some reference and guidance for scholars to examine TWP fixtures.

关键词： thin-walled part (TWP) fixture machining fixture categories fixture function

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Position-varying surface roughness prediction method considering compensated acceleration in milling of thin-walled

《机械工程前沿（英文）》 2021年第16卷第4期页码 855-867 doi: 10.1007/s11465-021-0649-z

摘要： Machined surface roughness will affect parts’ service performance. Thus, predicting it in the machining is important to avoid rejects. Surface roughness will be affected by system position dependent vibration even under constant parameter with certain toolpath processing in the finishing. Aiming at surface roughness prediction in the machining process, this paper proposes a position-varying surface roughness prediction method based on compensated acceleration by using regression analysis. To reduce the stochastic error of measuring the machined surface profile height, the surface area is repeatedly measured three times, and Pauta criterion is adopted to eliminate abnormal points. The actual vibration state at any processing position is obtained through the single-point monitoring acceleration compensation model. Seven acceleration features are extracted, and valley, which has the highest R-square proving the effectiveness of the filtering features, is selected as the input of the prediction model by mutual information coefficients. Finally, by comparing the measured and predicted surface roughness curves, they have the same trends, with the average error of 16.28% and the minimum error of 0.16%. Moreover, the prediction curve matches and agrees well with the actual surface state, which verifies the accuracy and reliability of the model.

关键词： surface roughness prediction compensated acceleration milling thin-walled workpiece

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Review on the progress of ultra-precision machining technologies

Julong YUAN, Binghai LYU, Wei HANG, Qianfa DENG

《机械工程前沿（英文）》 2017年第12卷第2期页码 158-180 doi: 10.1007/s11465-017-0455-9

摘要：

Ultra-precision machining technologies are the essential methods, to obtain the highest form accuracy and surface quality. As more research findings are published, such technologies now involve complicated systems engineering and been widely used in the production of components in various aerospace, national defense, optics, mechanics, electronics, and other high-tech applications. The conception, applications and history of ultra-precision machining are introduced in this article, and the developments of ultra-precision machining technologies, especially ultra-precision grinding, ultra-precision cutting and polishing are also reviewed. The current state and problems of this field in China are analyzed. Finally, the development trends of this field and the coping strategies employed in China to keep up with the trends are discussed.

关键词： ultra-precision grinding ultra-precision cutting ultra-precision polishing research status in China development tendency

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Gas marbles: ultra-long-lasting and ultra-robust bubbles formed by particle stabilization

《化学科学与工程前沿（英文）》页码 1681-1687 doi: 10.1007/s11705-022-2180-0

摘要： Bubbles and foams are ubiquitous in daily life and industrial processes. Studying their dynamic behaviors is of key importance for foam manufacturing processes in food packaging, cosmetics and pharmaceuticals. Bare bubbles are inherently fragile and transient; enhancing their robustness and shelf lives is an ongoing challenge. Their rupture can be attributed to liquid evaporation, thin film drainage and the nuclei of environmental dust. Inspired by particle-stabilized interfaces in Pickering emulsions, armored bubbles and liquid marble, bubbles are protected by an enclosed particle-entrapping liquid thin film, and the resultant soft object is termed gas marble. The gas marble exhibits mechanical strength orders of magnitude higher than that of soap bubbles when subjected to overpressure and underpressure, owing to the compact particle monolayer straddling the surface liquid film. By using a water-absorbent glycerol solution, the resulting gas marble can persist for 465 d in normal atmospheric settings. This particle-stabilizing approach not only has practical implications for foam manufacturing processes but also can inspire the new design and fabrication of functional biomaterials and biomedicines.

关键词： bubble particles interfaces armored bubble liquid marble gas marble Pickering emulsion

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Ribbed strip rolling by three-dimensional finite element method combining extremely thin array of elements

Zhengyi JIANG,

《机械工程前沿（英文）》 2010年第5卷第1期页码 52-60 doi: 10.1007/s11465-009-0087-9

摘要： In this paper, a three-dimensional finite element modelling of the ribbed strip rolling is carried out, coupling the use of an extremely thin array of elements that is equivalent to the calculation of the additional shear deformation work rate occurred by the velocity discontinuity in the roll bite. The formulation of the finite element modelling by adding a rib inclined contact surface boundary condition is derived, and the performance of the proposed method is conducted. The simulated rib height, forward slip, and the pulling down of rib height have been compared with the measured values and are in good agreement. The equivalent strain rate of the rib was obtained in the simulation. The effect of the rib inclined angle on pulling down of rib height has also been discussed, which is helpful in optimizing the design of the rib inclined angle.

关键词： rib inclined contact boundary condition ribbed strip extremely thin elements pulling down of rib height finite element modelling

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Properties of cement grout modified with ultra-fine slag

Sowmini GOPINATHAN, K B ANAND

《结构与土木工程前沿（英文）》 2018年第12卷第1期页码 58-66 doi: 10.1007/s11709-017-0383-0

摘要： The purpose of the study is to obtain a cement grout with improved performance. The grout mixes of the present study contain cement, ultra-fine slag (UFS), super plasticizer and water. Properties like flowability, bleeding, compressive strength and shrinkage of cement grouts have been studied. Rheological parameters were also studied in order to explain the grout workability. The results show that, cement replacement with slag in grouts could reduce bleeding substantially without affecting the workability of the mixes. Introduction of slag enhanced the compressive strength and reduced shrinkage reasonably. Ultra-fine slag can be used as a supplementary cementitious material in cementitious grouts in order to improve the grout behavior.

关键词： cement grout ultra-fine slag flowability bleeding viscosity

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An analytical method for calculating torsional constants for arbitrary complicated thin-walled cross-sections

DU Baisong, GE Yaojun, ZHOU Zheng

《结构与土木工程前沿（英文）》 2007年第1卷第3期页码 293-297 doi: 10.1007/s11709-007-0038-7

摘要： In this paper, an analytical method is proposed for calculating torsional constants for complicated thin-walled cross-sections with arbitrary closed or open rib stiffeners. This method uses the free torsional theory and the principle of virtual work to build governing equilibrium equations involving unknown shear flows and twisting rate. After changing the form of the equations and combining these two unknowns into one, torsional function, which is a function of shear flow, shear modulus, and twisting rate, is included in the governing equations as only one of the unknowns. All the torsional functions can be easily obtained from these homogeneous linear equations, and torsional constants can be easily obtained from the torsional functions. The advantage of this method is that we can easily and directly obtain torsional constants from the torsional functions, rather than the more sophisticated shear flow and twisting rate calculations. Finally, a complicated thin-walled cross-section is given as a valid numerical example to verify the analytical method, which is much more accurate and simpler than the traditional finite element method.

关键词： homogeneous complicated thin-walled numerical example advantage torsional function

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Recent development and application of thin-film thermoelectric cooler

Yuedong Yu, Wei Zhu, Xixia Kong, Yaling Wang, Pengcheng Zhu, Yuan Deng

《化学科学与工程前沿（英文）》 2020年第14卷第4期页码 492-503 doi: 10.1007/s11705-019-1829-9

摘要： Recently, the performance and fabrication of thin-film thermoelectric materials have been largely enhanced. Based on this enhancement, the thin-film thermoelectric cooler (TEC) is becoming a research hot topic, due to its high cooling flux and microchip level size. To fulfill a thin-film TEC, interfacial problems are unavoidable, as they may largely reduce the properties of a thin-film TEC. Moreover, the architecture of a thin-film TEC should also be properly designed. In this review, we introduced the enhancement of thermoelectric properties of (Bi,Sb) (Te,Se) solid solution materials by chemical vapor deposition, physical vapor deposition and electrodeposition. Then, the interfacial problems, including contact resistance, interfacial diffusion and thermal contact resistance, were discussed. Furthermore, the design, fabrication, as well as the performance of thin-film TECs were summarized.

关键词： thin-film thermoelectric cooler interfaces cooling flux TE device fabrication

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Stability analysis of large diameter thin-walled tube beam-columns

PAN Hanming, GUO Yanlin, LIANG Shuo, PEI Shengxing, LIANG Weisheng, WANG Lewen

《结构与土木工程前沿（英文）》 2008年第2卷第2期页码 123-132 doi: 10.1007/s11709-008-0017-7

摘要： Based on a blind spot in the current design standard of steel structures, the large diameter thin-walled tube beam-columns are analyzed using nonlinear finite element method in this paper. The influence of several factors on stability capacity of the large diameter thin-walled tube beam-columns is taken into account. Thus, according to the correlative design standard of steel structures, and on the basis of the numerical analytical results by the finite element methods, the calculation formulas of the stability bearing capacity are presented for beam-column members of the large diameter thin-walled tubes. Three tests of thin-walled steel tube beam-columns were reported. Test results for deformations and ultimate strength are found to be in a good agreement with the corresponding values predicted by the calculation formulas, and the proposed methods can be used in design practice.

关键词： ultimate strength nonlinear numerical analytical diameter thin-walled practice

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Surface-tailoring chlorine resistant materials and strategies for polyamide thin film composite reverse

《化学科学与工程前沿（英文）》 2022年第16卷第5期页码 564-591 doi: 10.1007/s11705-021-2109-z

摘要： Polyamide thin film composite membranes have dominated current reverse osmosis market on account of their excellent separation performances compared to the integrally skinned counterparts. Despite their very promising separation performance, chlorine-induced degradation resulted from the susceptibility of polyamide toward chlorine attack has been regarded as the Achilles’s heel of polyamide thin film composite. The free chlorine species present during chlorine treatment can impair membrane performance through chlorination and depolymerization of the polyamide selective layer. From material point of view, a chemically stable membrane is crucial for the sustainable application of membrane separation process as it warrants a longer membrane lifespan and reduces the cost involved in membrane replacement. Various strategies, particularly those involved membrane material optimization and surface modifications, have been established to address this issue. This review discusses membrane degradation by free chlorine attack and its correlation with the surface chemistry of polyamide. The advancement in the development of chlorine resistant polyamide thin film composite membranes is reviewed based on the state-of-the-art surface modifications and tailoring approaches which include the in situ and post-fabrication membrane modifications using a broad range of functional materials. The challenges and future directions in this field are also highlighted.

关键词： reverse osmosis polyamide thin film composite membranes chlorine resistance surface modification