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期刊论文 25

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关键词

串并联谐振变换器;全桥;半桥;变频;移相;宽范围输入电压 1

体硅键合技术 1

傅立叶红外光谱 1

共振隧穿器件(RTD);非相交分解算法;通用逻辑门;真值矩阵;函数综合算法 1

加权平均原则 1

加速湿热老化 1

化学键参数 1

即时医疗 1

原子半径差比率 1

大块金属玻璃 1

循环肿瘤细胞 1

微电子机械系统封装技术 1

扫描电子显微镜(SEM) 1

断裂性质 1

桉木纤维 1

滤波封装天线;玻璃通孔;三维封装器件;激光键合 1

热键合 1

玻璃形成能力 1

破坏模式 1

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Thermal transport properties of monolayer phosphorene: a mini-review of theoretical studies

Guangzhao QIN, Ming HU

《能源前沿(英文)》 2018年 第12卷 第1期   页码 87-96 doi: 10.1007/s11708-018-0513-y

摘要: Phosphorene, a two-dimensional (2D) elemental semiconductor with a high carrier mobility and intrinsic direct band gap, possesses fascinating chemical and physical properties distinctively different from other 2D materials. Its rapidly growing applications in nano-/opto-electronics and thermoelectrics call for fundamental understanding of the thermal transport properties. Considering the fact that there have been so many studies on the thermal transport in phosphorene, it is on emerging demand to have a review on the progress of previous studies and give an outlook on future work. In this mini-review, the unique thermal transport properties of phosphorene induced by the hinge-like structure are examined. There exists a huge deviation in the reported thermal conductivity of phosphorene in literature. Besides, the mechanism underlying the deviation is discussed by reviewing the effect of different functionals and cutoff distance in calculating the thermal transport properties of phosphorene. It is found that the (vdW) interactions play a key role in the formation of resonant bonding, which leads to long-ranged interactions. Taking into account of the vdW interactions and including the long-ranged interactions caused by the resonant bonding with large cutoff distance are important for getting the accurate and converged thermal conductivity of phosphorene. Moreover, a fundamental insight into the thermal transport is provided based on the review of resonant bonding in phosphorene. This mini-review summarizes the progress of the thermal transport in phosphorene and gives an outlook on future horizons, which would benefit the design of phosphorene based nano-electronics.

关键词: thermal transport     phosphorene     resonant bonding    

The electrostatic-alloy bonding technique used in MEMS

WANG Wei, CHEN Wei-ping

《机械工程前沿(英文)》 2006年 第1卷 第2期   页码 238-241 doi: 10.1007/s11465-006-0011-5

摘要: Electrostatic-alloy bonding of silicon wafer with glass deposited by Au to form Si/Au-glass water, and bonding of Si/Au-glass with silicon wafer were researched during fabrication of pressure sensors. The silicon wafer and glass wafer with an Au film resistor were bonded by electrostatic bonding, and then Si-Au alloy bonding was formed by annealing at 400vH for 2 h. The air sealability of the cavity after bonding was finally tested using the N filling method. The results indicate that large bond strength was obtained at the bonding interface. This process was used in fabricating a pressure sensor with a sandwich structure. The results indicate that the sensor presented better performances and that the bonding techniques can be used in MEMS packaging.

关键词: Si/Au-glass     strength     MEMS packaging     process     sandwich structure    

Ultraviolet exposure enhanced silicon direct bonding

Guanglan LIAO, Xuekun ZHANG, Xiaohui LIN, Canghai MA, Lei NIE, Tielin SHI,

《机械工程前沿(英文)》 2010年 第5卷 第1期   页码 87-92 doi: 10.1007/s11465-009-0078-x

摘要: Ultraviolet (UV) exposure, as an additional technique following the traditional wet chemical activation processes, is applied to enhance hydrophilic silicon direct bonding. The effects of UV exposure on silicon wafers’ nano-topography and bonding strength are studied. It is found that the surface roughness of silicon wafers initially decreases and then increases with UV exposure time, and the bonding strength increases and then decreases accordingly. The correlations of annealing temperature and annealing time vs. bonding strength are experimentally explored. Results indicate that the bonding strength increases sharply then gently with increasing annealing temperature and annealing time using UV exposure. Besides, the reliability of silicon direct bonding with UV exposure enhancement after the high/low temperature cycle test, constant temperature and humidity test, vibration test and shock test is investigated. It follows from the results that the bonding strength of silicon wafer pairs with UV exposure decreases after the environmental tests, whereas the residual strength is still higher than that without UV exposure, and the variation trends of bonding strength vs. UV exposure time, annealing temperature and annealing time remain unchanged. Therefore, following the traditional wet chemical activation processes, appropriate UV exposure (about three minutes in this study) is effective and promising to enhance silicon direct bonding.

关键词: ultraviolet (UV) exposure     silicon direct bonding     bonding strength     reliability    

Patterned wafer bonding using ultraviolet adhesive

Rui ZHUO, Guanglan LIAO, Wenliang LIU, Lei NIE, Tielin SHI

《机械工程前沿(英文)》 2011年 第6卷 第2期   页码 214-218 doi: 10.1007/s11465-011-0130-5

摘要:

The process of patterned wafer bonding using ultraviolet (UV) adhesive as the intermediate layer was studied. By presetting the UV adhesive guide-layer, controlling the thickness of the intermediate layer (1– 1.5 μm), appropriate pre-drying temperature (60°C), and predrying time (6 min), we obtained the intermediate layer bonding of patterned quartz/quartz. Experimental results indicate that patterned wafer bonding using UV adhesive is achieved under room temperature. The process also has advantages of easy operation, low cost, and no plugging or leakage in the patterned area after bonding. Using the process, a microfluidic chip for red blood cell counting was designed and fabricated. Patterned wafer bonding using UV adhesive will have great potential in the fabrication of microfluidic chips.

关键词: ultraviolet (UV) adhesive     intermediate layer     patterned wafer bonding    

A space solar cell bonding robot

FU Zhuang, ZHAO Yan-zheng, LIU Ren-qiang, DONG Zhi

《机械工程前沿(英文)》 2006年 第1卷 第3期   页码 360-363 doi: 10.1007/s11465-006-0027-x

摘要: A space solar cell bonding robot system which consists of a three-axis Cartesian coordinate s robot, coating device, bonding device, orientation plate, and control subsystem was studied. A method, which can control the thickness o

关键词: Cartesian coordinate     thickness     three-axis Cartesian     orientation     control subsystem    

淀粉基API胶合木胶接结构破坏模式及失效机理

时君友,徐文彪,王淑敏

《中国工程科学》 2014年 第16卷 第4期   页码 40-44

摘要:

以淀粉基水性高分子异氰酸酯(API)胶合木胶接结构为研究对象,以胶接的压缩剪切强度为评估指标,通过加速湿热老化试验对胶接结构的破坏模式和失效机理进行了研究。结果表明:胶接结构的断裂性质为韧性断裂,且随着老化时间的增加,其破坏模式为由内聚破坏向内聚破坏+界面破坏转变。在湿热老化试验前期温度对压缩剪切试样性能起主要作用,在老化后期湿度起主要作用。

关键词: 胶接结构     加速湿热老化     断裂性质     破坏模式    

High-bandwidth nanopositioning via active control of system resonance

Linlin LI, Sumeet S. APHALE, Limin ZHU

《机械工程前沿(英文)》 2021年 第16卷 第2期   页码 331-339 doi: 10.1007/s11465-020-0619-x

摘要: Typically, the achievable positioning bandwidth for piezo-actuated nanopositioners is severely limited by the first, lightly-damped resonance. To overcome this issue, a variety of open- and closed-loop control techniques that commonly combine damping and tracking actions, have been reported in literature. However, in almost all these cases, the achievable closed-loop bandwidth is still limited by the original open-loop resonant frequency of the respective positioning axis. Shifting this resonance to a higher frequency would undoubtedly result in a wider bandwidth. However, such a shift typically entails a major mechanical redesign of the nanopositioner. The integral resonant control (IRC) has been reported earlier to demonstrate the significant performance enhancement, robustness to parameter uncertainty, gua-ranteed stability and design flexibility it affords. To further exploit the IRC scheme’s capabilities, this paper presents a method of actively shifting the resonant frequency of a nanopositioner’s axis, thereby delivering a wider closed-loop positioning bandwidth when controlled with the IRC scheme. The IRC damping control is augmented with a standard integral tracking controller to improve positioning accuracy. And both damping and tracking control parameters are analytically optimized to result in a Butterworth Filter mimicking pole-placement—maximally flat passband response. Experiments are conducted on a nanopositioner’s axis with an open-loop resonance at 508 Hz. It is shown that by employing the active resonance shifting, the closed-loop positioning bandwidth is increased from 73 to 576 Hz. Consequently, the root-mean-square tracking errors for a 100 Hz triangular trajectory are reduced by 93%.

关键词: nanopositioning stage     high-bandwidth     resonant mode control     tracking control     integral resonant control    

Flexible resonant tank for a combined converter to achieve an HPS and LED compatible driver

Jin HU,Hui-pin LIN,Zheng-yu LU,Feng-wu ZHOU

《信息与电子工程前沿(英文)》 2015年 第16卷 第8期   页码 679-693 doi: 10.1631/FITEE.1500054

摘要: High pressure sodium (HPS) lamp has been widely used in street lighting applications because of its maturity, reliability, high lighting efficiency, long life-time, and low cost. Light emitting diode (LED) is expected as the next generation lighting source due to its continuously improving luminous efficacy, better color characteristic, and super long life-time. The two lighting sources may coexist in street lighting applications for a long time. A novel HPS and LED compatible driver is proposed which is rather suitable and flexible for driving HPS and LED in street lighting applications. The proposed driver combines the LLC and LCC resonant circuits into a flexible resonant tank. The flexible resonant tank may change to LLC or isolated LCC circuit according to the lighting source. It inherits the traditional HPS and LED drivers’ zero voltage switching (ZVS) characteristics and dimmable function. The design of the proposed flexible resonant tank considers the requirements of both HPS and LED. The experiments of driving HPS and LED on a prototype driver show that the driver can drive the two lighting sources flexibly with high efficiency.

关键词: High pressure sodium (HPS)     Light emitting diode (LED)     Compatible driver     Ballast    

Analysis of resonant coupling coil configurations of EV wireless charging system: a simulation study

M. LU, A. JUNUSSOV, M. BAGHERI

《能源前沿(英文)》 2020年 第14卷 第1期   页码 152-165 doi: 10.1007/s11708-019-0615-1

摘要: Nowadays, internal combustion engine vehicles are considered as one of the major contributors to air pollution. To make transportation more environmentally friendly, plug-in electric vehicles (PEVs) have been proposed. However, with an increase in the number of PEVs, the drawbacks associated with the cost and size, as well as charging cables of batteries have arisen. To address these challenges, a novel technology named wireless charging system has been recently recommended. This technology rapidly evolves and becomes very attractive for charging operations of electric vehicles. Currently, wireless charging systems offer highly efficient power transfer over the distances ranging from several millimeters to several hundred millimeters. This paper is focused on analyzing electromagnetically coupled resonant wireless technique used for the charging of EVs. The resonant wireless charging system for EVs is modeled, simulated, and then examined by changing different key parameters to evaluate how transfer distance, load, and coil’s geometry, precisely number of coil’s turns, coil’s shape, and inter-turn distance, influence the efficiency of the charging process. The simulation results are analyzed and critical dimensions are discussed. It is revealed that a proper choice of the dimensions, inter-turn distance, and transfer distance of the coil can result in a significant improvement in charging efficiency. Furthermore, the influence of the transfer distance, frequency, load, as well as the number of the turns of the coil on the performance of wireless charging system is the main focus of this paper.

关键词: electromagnetically coupled resonator     near-field power transfer     wireless power transfer (WPT)    

Towards Cr(VI)-free anodization of aluminum alloys for aerospace adhesive bonding applications: A review

Shoshan T. Abrahami, John M. M. de Kok, Herman Terryn, Johannes M. C. Mol

《化学科学与工程前沿(英文)》 2017年 第11卷 第3期   页码 465-482 doi: 10.1007/s11705-017-1641-3

摘要: For more than six decades, chromic acid anodizing (CAA) has been the central process in the surface pre-treatment of aluminum for adhesively bonded aircraft structures. Unfortunately, this electrolyte contains hexavalent chromium (Cr(VI)), a compound known for its toxicity and carcinogenic properties. To comply with the new strict international regulations, the Cr(VI)-era will soon have to come to an end. Anodizing aluminum in acid electrolytes produces a self-ordered porous oxide layer. Although different acids can be used to create this type of structure, the excellent adhesion and corrosion resistance that is currently achieved by the complete Cr(VI)-based process is not easily matched. This paper provides a critical overview and appraisal of proposed alternatives to CAA, including combinations of multiple anodizing steps, pre- and post anodizing treatments. The work is presented in terms of the modifications to the oxide properties, such as morphological features (e.g., pore size, barrier layer thickness) and surface chemistry, in order to evaluate the link between fundamental principles of adhesion and bond performance.

关键词: aluminum     Cr(VI)-free     surface pre-treatments     anodizing     adhesive bonding    

ARC welding method for bonding steel with aluminum

Zhenyang LU, Pengfei HUANG, Wenning GAO, Yan LI, Hanpeng ZHANG, Shuyan YIN

《机械工程前沿(英文)》 2009年 第4卷 第2期   页码 134-146 doi: 10.1007/s11465-009-0033-x

摘要: When welding steel with aluminum, the appearance of intermetallic compounds of Fe and Al will decrease tenacity and increase rigidity, which leads to bad joint performance. A new type of low energy input (LEI) welding technology is introduced which can be used to weld steel with aluminum. Using the technology, brazing was located on the steel side and arc fusion welding on the aluminum side. The less heat input reduces the thickness of intermetallic compounds to 3-4 μm. Tensile strength tests prove that the joint breaks at the heat-affected zone and the strength is higher than 70% of the aluminum’s. Thus, the method can lead to a good performance joint.

关键词: joining of steel and aluminum     low energy input welding     arc welding     fusion welding – brazing    

用于微电子机械系统封装的体硅键合技术和薄膜密封技术

王渭源,王跃林

《中国工程科学》 2002年 第4卷 第6期   页码 56-62

摘要:

对静电键合、体硅直接键合和界面层辅助键合等三种体硅键合技术,整片操作、局部操作和选择保护等三种密封技术,以及这些技术用于微电子机械系统的密封作了评述,强调在器件研究开始时应考虑封装问题,具体技术则应在保证器件功能和尽量减少芯片复杂性两者之间权衡决定。

关键词: 体硅键合技术     薄膜密封技术     微电子机械系统封装技术    

Hyperbranched magnetic polymer: highly efficient removal of Cr(VI) and application in electroplating wastewater

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1568-1580 doi: 10.1007/s11705-023-2303-2

摘要: By using a two-step hydrothermal method and trithiocyanuric acid (TTCA), 2,4,6-trihydrazino-1,3,5-triazine (THT), and Fe3O4 as raw materials, a spherical magnetic adsorbent polymer (TTCA/THT@Fe3O4) was synthesized to achieve the efficient removal of Cr(VI) from wastewater. Under optimal adsorption conditions, the maximum adsorption capacity of TTCA/THT@Fe3O4 for Cr(VI) can reach 1340 mg∙g‒1. Notably, the removal efficiency can approach 98.9%, even at the lower concentration of 20 mg∙L‒1 Cr(VI). For actual wastewater containing Cr(VI), the Cr(VI) concentration was reduced from 25.8 to 0.4 mg∙L‒1, a remarkable 20% lower than the current industry discharge standard value. A mechanism for the high adsorption performance of Cr(VI) on TTCA/THT@Fe3O4 was investigated using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and density functional theory. It can be plausibly attributed to the formation of Cr/N and Cr/S coordination bonds. Additionally, surface electrostatic adsorption, reduction effects, and the spherical polymer structure increase the contact area with Cr(VI), maximizing adsorption. The synergistic effect of adsorption and reduction enhances the adsorption performance of TTCA/THT@Fe3O4 for Cr(VI) and total chromium in water. The resultant polymer has a simple preparation process, excellent adsorption performance, easy magnetic separation, and promising application for actual wastewater.

关键词: magnetic polymer     chromium removal     hydrogen bonding     recyclability     actual wastewater    

Design of ultrasonic elliptical vibration cutting system for tungsten heavy alloy

《机械工程前沿(英文)》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0715-1

摘要: Nanoscale surface roughness of tungsten heavy alloy components is required in the nuclear industry and precision instruments. In this study, a high-performance ultrasonic elliptical vibration cutting (UEVC) system is developed to solve the precision machining problem of tungsten heavy alloy. A new design method of stepped bending vibration horn based on Timoshenko’s theory is first proposed, and its design process is greatly simplified. The arrangement and working principle of piezoelectric transducers on the ultrasonic vibrator using the fifth resonant mode of bending are analyzed to realize the dual-bending vibration modes. A cutting tool is installed at the end of the ultrasonic vibration unit to output the ultrasonic elliptical vibration locus, which is verified by finite element method. The vibration unit can display different three-degree-of-freedom (3-DOF) UEVC characteristics by adjusting the corresponding position of the unit and workpiece. A dual-channel ultrasonic power supply is developed to excite the ultrasonic vibration unit, which makes the UEVC system present the resonant frequency of 41 kHz and the maximum amplitude of 14.2 μm. Different microtopography and surface roughness are obtained by the cutting experiments of tungsten heavy alloy hemispherical workpiece with the UEVC system, which validates the proposed design’s technical capability and provides optimization basis for further improving the machining quality of the curved surface components of tungsten heavy alloy.

关键词: tungsten heavy alloy     ultrasonic elliptical vibration cutting     Timoshenko’s theory     resonant mode of bending     finite element method    

Performance of steel bridge deck pavement structure with ultra high performance concrete based on resin bonding

《结构与土木工程前沿(英文)》 2021年 第15卷 第4期   页码 895-904 doi: 10.1007/s11709-021-0759-z

摘要: This research investigated a pavement system on steel bridge decks that use epoxy resin (EP) bonded ultra-high performance concrete (UHPC). Through FEM analysis and static and dynamic bending fatigue tests of the composite structure, the influences of the interface of the pavement layer, reinforcement, and different paving materials on the structural performance were compared and analyzed. The results show that the resin bonded UHPC pavement structure can reduce the weld strain in the steel plate by about 32% and the relative deflection between ribs by about 52% under standard axial load conditions compared to traditional pavements. The EP bonding layer can nearly double the drawing strength of the pavement interface from 1.3 MPa, and improve the bending resistance of the UHPC structure on steel bridge decks by about 50%; the bending resistance of reinforced UHPC structures is twice that of unreinforced UHPC structure, and the dynamic deflection of the UHPC pavement structure increases exponentially with increasing fatigue load. The fatigue life is about 1.2 × 107 cycles under a fixed force of 9 kN and a dynamic deflection of 0.35 mm, which meets the requirements for fatigue performance of pavements on steel bridge decks under traffic conditions of large flow and heavy load.

关键词: steel bridge deck pavement     ultra-high-performance concrete     epoxy resin     composite structure     bending fatigue performance    

标题 作者 时间 类型 操作

Thermal transport properties of monolayer phosphorene: a mini-review of theoretical studies

Guangzhao QIN, Ming HU

期刊论文

The electrostatic-alloy bonding technique used in MEMS

WANG Wei, CHEN Wei-ping

期刊论文

Ultraviolet exposure enhanced silicon direct bonding

Guanglan LIAO, Xuekun ZHANG, Xiaohui LIN, Canghai MA, Lei NIE, Tielin SHI,

期刊论文

Patterned wafer bonding using ultraviolet adhesive

Rui ZHUO, Guanglan LIAO, Wenliang LIU, Lei NIE, Tielin SHI

期刊论文

A space solar cell bonding robot

FU Zhuang, ZHAO Yan-zheng, LIU Ren-qiang, DONG Zhi

期刊论文

淀粉基API胶合木胶接结构破坏模式及失效机理

时君友,徐文彪,王淑敏

期刊论文

High-bandwidth nanopositioning via active control of system resonance

Linlin LI, Sumeet S. APHALE, Limin ZHU

期刊论文

Flexible resonant tank for a combined converter to achieve an HPS and LED compatible driver

Jin HU,Hui-pin LIN,Zheng-yu LU,Feng-wu ZHOU

期刊论文

Analysis of resonant coupling coil configurations of EV wireless charging system: a simulation study

M. LU, A. JUNUSSOV, M. BAGHERI

期刊论文

Towards Cr(VI)-free anodization of aluminum alloys for aerospace adhesive bonding applications: A review

Shoshan T. Abrahami, John M. M. de Kok, Herman Terryn, Johannes M. C. Mol

期刊论文

ARC welding method for bonding steel with aluminum

Zhenyang LU, Pengfei HUANG, Wenning GAO, Yan LI, Hanpeng ZHANG, Shuyan YIN

期刊论文

用于微电子机械系统封装的体硅键合技术和薄膜密封技术

王渭源,王跃林

期刊论文

Hyperbranched magnetic polymer: highly efficient removal of Cr(VI) and application in electroplating wastewater

期刊论文

Design of ultrasonic elliptical vibration cutting system for tungsten heavy alloy

期刊论文

Performance of steel bridge deck pavement structure with ultra high performance concrete based on resin bonding

期刊论文