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薄膜润滑 5

Cu(In 4

Ga)Se₂ 3

粘度 3

CCS 1

CO₂分离 1

Ga)Se₂光伏组件 1

Ni–Ti–Cu–V合金 1

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VO₂薄膜 1

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人造金刚石 1

人造金刚石膜 1

仅1吸收 1

低光增强；过滤—群聚注意力；密集连接金字塔；递归网络 1

低温 1

体硅键合技术 1

催化膜反应器 1

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Surface modification by ligand growth strategy for dense copper bismuth film as photocathode to enhance

《能源前沿（英文）》 doi: 10.1007/s11708-023-0893-5

摘要： Hydrogen production from photoelectrochemical (PEC) water splitting has been regarded as a promising way to utilize renewable and endless solar energy. However, semiconductor film grown on photoelectrode suffers from numerous challenges, leading to the poor PEC performance. Herein, a straightforward sol-gel method with the ligand-induced growth strategy was employed to obtain dense and homogeneous copper bismuthate photocathodes for PEC hydrogen evolution reaction. By various characterizations, it was found that the nucleation and surface growth of CuBi₂O₄ layer induced by 2-methoxyethanol ligand (2-CuBi₂O₄) demonstrated a decent crystallinity and coverage, as well as a large grain size and a low oxygen vacancy concentration, leading to the good ability of light absorption and carrier migration. Consequently, under simulated sunlight irradiation (AM1.5G, 100 mW/cm²), the 2-CuBi₂O₄ photocathode achieved an enhanced photocurrent density of −1.34 mA·cm⁻² at 0.4 V versus the reversible hydrogen electrode and a promising applied bias photon-to-current efficiency of 0.586%. This surface modification by ligand growth strategy will shed light on the future design of advanced photoelectrodes for PEC water splitting.

关键词： copper bismuthate photocathode ligand growth strategy dense film PEC

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Low crosstalk switch unit for dense piezoelectric sensor networks

Lei QIU, Shenfang YUAN,

《机械工程前沿（英文）》 2009年第4卷第4期页码 401-406 doi: 10.1007/s11465-009-0047-4

摘要： Structural health monitoring (SHM), on the basis of piezoelectric (PZT) sensors and lamb wave method, is efficient in estimating the state of monitored structures. Furthermore, to monitor large-scale structures, dense piezoelectric sensor networks are required, which usually contain many piezoelectric sensor pairs called actuator-sensor channels. In that case, considering the few data acquisition channels especially in the data acquisition board with a high sampling rate and limited quantity of signal amplifiers used in an integrated computer system, a switch unit is adopted to switch to different channels. Because of the high frequency and power of the lamb wave excitation signal, there exists a crosstalk signal in the switch unit. A large crosstalk signal is mixed into the response signal so that the on/off-line signal processing task is difficult to achieve. This paper first analyzes the crosstalk signal phenomenon, describes its production mechanism, and proposes a method to reduce it. Then a 24-switch channel low crosstalk switch unit based on a digital I/O board PCI7248 produced by Adlink technology is developed. An experiment is implemented to validate it. Its low crosstalk characteristics make it promote the real application of the SHM based active lamb wave method. Finally, a general software program based on LabVIEW software platform is developed to control this switch unit.

关键词： structural health monitoring (SHM) piezoelectric (PZT) sensor networks switch unit crosstalk signal

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Building a dense surface map incrementally from semi-dense point cloud andRGBimages

Qian-shan LI,Rong XIONG,Shoudong HUANG,Yi-ming HUANG

《信息与电子工程前沿（英文）》 2015年第16卷第7期页码 594-606 doi: 10.1631/FITEE.14a0260

摘要： Building and using maps is a fundamental issue for bionic robots in field applications. A dense surface map, which offers rich visual and geometric information, is an ideal representation of the environment for indoor/outdoor localization, navigation, and recognition tasks of these robots. Since most bionic robots can use only small light-weight laser scanners and cameras to acquire semi-dense point cloud and RGB images, we propose a method to generate a consistent and dense surface map from this kind of semi-dense point cloud and RGB images. The method contains two main steps: (1) generate a dense surface for every single scan of point cloud and its corresponding image(s) and (2) incrementally fuse the dense surface of a new scan into the whole map. In step (1) edge-aware resampling is realized by segmenting the scan of a point cloud in advance and resampling each sub-cloud separately. Noise within the scan is reduced and a dense surface is generated. In step (2) the average surface is estimated probabilistically and the non-coincidence of different scans is eliminated. Experiments demonstrate that our method works well in both indoor and outdoor semi-structured environments where there are regularly shaped objects.

关键词： Bionic robot Robotic mapping Surface fusion

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Visualization of force networks in 2D dense granular materials

Jianguo LIU, Qicheng SUN, Feng JIN,

《结构与土木工程前沿（英文）》 2010年第4卷第1期页码 109-115 doi: 10.1007/s11709-010-0003-8

摘要： Dense granular matter is a conglomeration of discrete solid and closely packed particles. As subjected to external loadings, the stress is largely transmitted by heavily stressed chains of particles forming a sparse network of larger contact forces. To understand the structure and evolution of force chains, a photoelastic technique was improved for determining stresses and strains in the assemblies of photoelastic granular disks in this paper. A two-dimensional vertical slab was designed. It contains 7200 polydispersed photoelastic disks and is subjected to a localized probe penetrating at the top of the slab to mimic the cone penetration test. The interparticle contact force distribution was found a peak around the mean value, a roughly exponential tail for greater force and a dip toward zero for smaller force. The force chain network around the probe tip was depicted, and the contact angle distribution of particles in force chains was found to be well aligned in the directions of major principal stress.

关键词： granular matter force chain multiscale modeling

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Mesoscopic properties of dense granular materials: An overview

Qicheng SUN, Feng JIN, Guohua ZHANG

《结构与土木工程前沿（英文）》 2013年第7卷第1期页码 1-12 doi: 10.1007/s11709-013-0184-z

摘要： A granular material is a conglomeration of discrete solid particles. It is intrinsically athermal because its dynamics always occur far from equilibrium. In highly excited gaseous states, it can safely be assumed that only binary interactions occur and a number of kinetic theories have been successfully applied. However, for granular flows and solid-like states, the theory is still poorly understood because of the internally correlated structures, such as particle clusters and force networks. The current theory is that the mesoscale characteristics define the key differences between granular materials and homogeneous solid materials. Widespread interest in granular materials has arisen among physicists, and significant progress has been made, especially in understanding the jamming phase diagram and the characteristics of the jammed phase. In this paper, the underlying physics of the mesoscale structure is discussed in detail. A multiscale framework is then proposed for dense granular materials.

关键词： granular matter macroscopic structure jamming phase transition

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Numerical simulation of liquid falling film on horizontal circular tubes

Fengdan SUN, Songlin XU, Yongchuan GAO

《化学科学与工程前沿（英文）》 2012年第6卷第3期页码 322-328 doi: 10.1007/s11705-012-1296-z

摘要： The objective of this study is to investigate numerically the flow characteristics of falling film on horizontal circular tubes. Numerical simulations are performed using FLUENT for 2D configurations with one and two cylinders. The volume of fluid method is used to track the motion of liquid falling film and the gas-liquid interface. The effect of flow characteristics on heat and transfer coefficient may be remarkable, although it has been neglected in previous studies. The velocity distribution and the film thickness characteristics on the top tube, some special flow characteristics on the bottom tube, intertube flow modes and effect of liquid feeder height on flow characteristics have been studied. Our simulations indicate that 1) the velocity distributions of the upper and lower parts of the tube are not strictly symmetric and non-uniform, 2) the film thickness depends on flow rate and angular distributions, 3) the flow characteristics of the top tube are different from those of the bottom tube, 4) three principal and two intermediate transition modes are distinguished, and 5) the liquid feed height plays an important role on the formation of falling film. The numerical results are in a good agreement with the theoretical values by the Nusselt model and the reported results.

关键词： falling film horizontal tube flow characteristics film thickness liquid feeder height

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Assessment and validation of liquid breakup models for high-pressure dense diesel sprays

Yi REN,Xianguo LI

《能源前沿（英文）》 2016年第10卷第2期页码 164-175 doi: 10.1007/s11708-016-0407-9

摘要： Liquid breakup in fuel spray and atomization significantly affects the consequent mixture formation, combustion behavior, and emission formation processes in a direct injection diesel engine. In this paper, different models for liquid breakup processes in high-pressure dense diesel sprays and its impact on multi-dimensional diesel engine simulation have been evaluated against experimental observations, along with the influence of the liquid breakup models and the sensitivity of model parameters on diesel sprays and diesel engine simulations. It is found that the modified Kelvin-Helmholtz (KH)–Rayleigh-Taylor (RT) breakup model gives the most reasonable predicted results in both engine simulation and high-pressure diesel spray simulation. For the standard KH-RT model, the model constant for the breakup length has a significant effect on the predictability of the model, and a fixed value of the constant cannot provide a satisfactory result for different operation conditions. The Taylor-analogy-breakup (TAB) based models and the RT model do not provide reasonable predictions for the characteristics of high-pressure sprays and simulated engine performance and emissions.

关键词： breakup model diesel engine high-pressure injection simulations

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Experiment and optimal design of a collection device for a residual plastic film baler

Qi NIU,Xuegeng CHEN,Chao JI,Jie WU

《农业科学与工程前沿（英文）》 2015年第2卷第4期页码 347-354 doi: 10.15302/J-FASE-2015077

摘要： It is imperative to carry out research on residual plastic film collection technology to solve the serious problem of farmland pollution. The residual plastic film baler was designed as a package for film strip collection, cleaning and baling. The collection device is a core component of the baler. Response surface analysis was used in this study to optimize the structure and working parameters for improving the collection efficiency of residual film and the impurity of film package. The results show that the factors affecting the collection rate of residual film and the impurity of the film package are the speed ratio ( ) between the trash removal roller and eccentric collection mechanism, the number ( ) and the mounting angle ( ) of spring teeth in the same revolution plane. For the collection rate, the importance of the three factors are in the order, . Meanwhile, for the impurity, the importance of three factors are in the order, . When the speed ratio, the mounting angle and the number of spring teeth was set at 1.6°, 45°, and 8°, respectively, the collection rate of residual film was 88.9% and the impurity of residual film package was 14.2% for the baler.

关键词： residual film collection device collection rate of residual film impurity of film package optimization baler

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薄膜润滑研究的回顾与展望

雒建斌,张朝辉,温诗铸

《中国工程科学》 2003年第5卷第7期页码 84-89

摘要：

薄膜润滑是20世纪90年代以来广泛研究的新型润滑状态。它是界于弹流润滑和边界润滑之间的一种过渡润滑状态，有着自己独特的润滑规律。文章回顾了薄膜润滑的研究历史，包括薄膜润滑概念的提出、测试技术的发展、薄膜润滑的膜厚特性、润滑机理探索以及计算理论等方面的研究成果与主要进展。

关键词：薄膜润滑有序膜膜厚测量微结构

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Thin-liquid-film evaporation at contact line

Hao WANG, Zhenai PAN, Zhao CHEN

《能源前沿（英文）》 2009年第3卷第2期页码 141-151 doi: 10.1007/s11708-009-0020-2

摘要： When a liquid wets a solid wall, the extended meniscus near the contact line may be divided into three regions: a nonevaporating region, where the liquid is adsorbed on the wall; a transition region or thin-film region, where effects of long-range molecular forces (disjoining pressure) are felt; and an intrinsic meniscus region, where capillary forces dominate. The thin liquid film, with thickness from nanometers up to micrometers, covering the transition region and part of intrinsic meniscus, is gaining interest due to its high heat transfer rates. In this paper, a review was made of the researches on thin-liquid-film evaporation. The major characteristics of thin film, thin-film modeling based on continuum theory, simulations based on molecular dynamics, and thin-film profile and temperature measurements were summarized.

关键词： meniscus thin film contact line disjoining pressure evaporation

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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

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Piezoelectric film-actuated motion platform with high resolution

HUA Shunming, ZHANG Hongzhuang, CHENG Guangming, FAN Zunqiang, LIU Jianfang

《机械工程前沿（英文）》 2008年第3卷第3期页码 265-269 doi: 10.1007/s11465-008-0041-2

摘要： A piezoelectric film-actuated motion platform with high resolution, which can run in two directions within a horizontal plane, is presented. On the basis of the analysis of the working principle of a stick-slip mechanism, a mathematical model describing its dynamic behavior is set up and simulated. Experiments of the motion performance and carrying ability on the prototype are conducted. Results show that this type of platform has advantages including a simple structure, small volume, light weight, stable step length, and large traveling range. When the driving voltage is less than 30 V, step error is less than 0.5 ?m. The carrying ability of the platform is terrific and about 7–8 times its weight.

关键词： mathematical stick-slip mechanism piezoelectric film-actuated analysis terrific

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Heat and mass transfer of ammonia-water in falling film evaporator

Xianbiao BU, Weibin MA, Huashan LI

《能源前沿（英文）》 2011年第5卷第4期页码 358-366 doi: 10.1007/s11708-011-0161-y

摘要： To investigate the performance of heat and mass transfer of ammonia-water during the process of falling film evaporation in vertical tube evaporator, a mathematical model of evaporation process was presented, the solution of which that needed a coordinate transformation was based on stream function. The computational results from the mathematical model were validated with experimental data. Subsequently, a series of parameters, such as velocity, film thickness and concentration, etc., were obtained from the mathematical model. Calculated results show that the average velocity and the film thickness change dramatically at the entrance region when <100 mm, while they vary slightly with the tube length in the fully developed region when >100 mm. The average concentration of the solution reduces along the tube length because of evaporation, but the reducing tendency becomes slow. It can be concluded that there is an optimalβrelationship between the tube length and the electricity generated. The reason for the bigger concentration gradient in the direction is that the smooth tube is chosen in the calculation. It is suggested that the roll-worked enhanced tube or other enhanced tube can reduce the concentration gradient in the film thickness direction and enhance the heat and mass transfer rate.

关键词： falling film evaporation ammonia-water heat and mass transfer

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Dynamic analysis of free-surface thin film flows driven by gravity over undulated substrate

Zhaomiao LIU, Xin LIU, Guobin WANG, Hong LIAO,

《机械工程前沿（英文）》 2010年第5卷第2期页码 219-225 doi: 10.1007/s11465-010-0010-4

摘要： This paper studies thin film flows with free surfaces driven by gravity through two types of undulated planes: periodically sinusoidal plane and triangle. The substrate plane is fixed and inclined to a certain angle and the flow with a free surface. Through finite element method (FEM), commenced from Navier-Stokes equations and continuity equation, the exact numerical results of free-surface film flows are obtained through discretization solution to finite equations in flowing areas. Based on the numerical calculations, the streamlines and wall shearing stress during the flowing process are visualized via post-proceeding, and the streamlines separation, the onset and evolution of vortex near the substrate boundary during the flow are also analyzed. The influences from the waviness of the substrate planes profile, height of the triangle plane, and change of the film height on film flow dynamics properties are shown.

关键词： waviness triangle height film thickness streamlines separation vortex

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Improved film evaporator for mechanistic understanding of microwave-induced separation process

Xin Gao, Dandan Shu, Xingang Li, Hong Li

《化学科学与工程前沿（英文）》 2019年第13卷第4期页码 759-771 doi: 10.1007/s11705-019-1816-1

摘要： Microwave-induced film evaporation separation process has been reported recently to separate the polar/nonpolar mixture. However, the efficiency of the separation is still too low for practical applications, which requires further enhancement via different strategies such as optimization design of evaporator structure. In addition the depth understanding of the separation mechanisms is great importance for better utilization of the microwave-induced separation process. To carry out these investigations, a novel microwave-induced falling film evaporation instrument was developed in this paper. The improvement of the enhancement effect of microwave-induced separation was observed based on the improved film evaporator. The systematic experiments on microwave-induced separation with different binary azeotropic mixtures (ethanol-ethyl acetate system and dimethyl carbonate (DMC)-H O system) were conducted based on the new evaporator. For the ethanol-ethyl acetate system, microwave irradiation shift the direction of evaporation separation at higher ethanol content in the starting liquid mixture. Moreover, for DMC-H O system microwave-induced separation process broke through the limitations of the traditional distillation process. The results clearly demonstrated the microwave-induced evaporation separation process could be commendably applied to the separation of binary azeotrope with different dielectric properties. Effects of operating parameters are also investigated to trigger further mechanism understanding on the microwave-induced separation process.

关键词： process intensification microwave falling film evaporation separation azeotrope