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Experiments of Air-pocket Movement in an 18.2odownward 240-mm Conduit

Procedia Engineering 2012年 28卷 791-795页

作者： Ting Liu James Yang River Engineering Royal Institute of Technology (KTH) SE-100 44 Stockholm Sweden Vattenfall Research & Development (R&D) SE-814 26 Älvkarleby Sweden

Experiments are carried out in a test rig, consisting of a Plexiglas pipe with an inner diameter of 240 mm and an inclination of 18.2o, to investigate air-water two-phase flows in conjunction with bottom spillways. results show that the critical velocity, which is the minimal water velocity to start moving an air pocket, in the rough pipe, is independent of the air-pocket volume; in the smooth pipe it doesn’t increase with increasing diameter as much as the previous researchers indicated. Pipe roughness doesn’t affect the velocity of the air-pocket when it moves upstream in the downward inclined pipe.

关键词： two-phase flow Air pocket Critical velocity roughness effect diameter effect

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decarburization of ferrochrome and high alloy steels with optimized gas and slag phases towards improved Cr retention

Decarburization of ferrochrome and high alloy steels with op...

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Ninth International Conference on Molten Slags,Fluxes and Salts(MOLTEN12)

作者： Mselly M.NZOTTA Seshadri SEETHArAMAN Research & Development(R&D) Process Development(Metallurgy)Uddeholms ABHagforsSweden. Division of Materials Process Science Royal Institute of TechnologyStockholmSweden.

Chromium is a high value metal and the retention of the same during the refining of high carbon ferrochrome(HCFeCr) as well as high alloy steel has significant economic and environmental impacts. The loss of chromium ... 详细信息

关键词： CO2 Cr retention partial pressure decarburizer temperature control

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Exploration on use of ferrofluid in power transformers

Exploration on use of ferrofluid in power transformers

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International Conference on Properties and Applications of Properties and Applications of dielectric Materials

作者： Sushil Chaudhari Shubhangi Patil rahul Zambare Sruti Chakraborty Global Research and Development Crompton Greaves Mumbai India Global R&D Crompton Greaves Mumbai Department of Chemical Technology NMU Jalgaon India

during normal operating conditions, the thermal fluctuation in a power transformer is controlled by the mineral insulating oil that acts as cooling media and keeps the transformer in thermal equilibrium. Feasibility of ferrofluid in power transformers and compatibility with the transformer components have been quite an area of interest even after it has surfaced as a possible dielectric fluid with enhanced heat dissipation capacity. The experimental contributions in this research are dedicated towards the comparison of ferrofluid and naphthenic oil with kraft paper where major emphasis has been laid on the results obtained from long term laboratory scale ageing of ferrofluid for 61days at 393 K (120°C) with respect to the dissolved gas analysis (dGA), moisture, and degree of polymerization (dP) of solid insulation along with oxidation stability and rotating Bomb Oxidation Test (rBOT) with kraft paper.

关键词： Polymers Gases Oxidation Stability analysis Moisture Copper Educational institutions

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Fabrication of high aspect grating using bonded substrate for X-ray refraction imaging by Talbot-Lau interferometer

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AIP Conference Proceedings 2012年第1期1466卷 181-186页

作者： Takuji Tada dai Murakoshi Hiroyasu Ishii Atsushi Hashimoto Yasuhisa Kaneko Wataru Ito Toshitaka Agano Medical Systems Research & Development Center R&D Management Headquarters FUJIFILM Corp. 798 Miyanodai Kaisei-machi Ashigarakami-gun Kanagawa 258-8538 Japan Imaging Technology Center R&D Management Headquarters FUJIFILM Corp. 798 Miyanodai Kaisei-machi Ashigarakami-gun Kanagawa 258-8538 Japan

In order to improve the image quality of X-ray refraction images using a Talbot-Lau interferometer, we have been attempting to fabricate gratings with high aspect ratio. In our attempt, deep grooves of grating structure were channeled on a Si substrate bonded by Au diffusion bonding method, and the grooves were filled with Au where the Au layer used for the bonding Si substrate was acting as a seed layer of Au electroplating. From the results of a visibility measurement and a cross sectional SEM image, it was confirmed that the grooves with a pitch of 5.8 μm and a depth of 100 μm could be successfully filled with Au over a large area of 72×80 mm2. Using this grating, the X-ray refraction images for the cartilage of a knee joint of a livestock pig could be obtained where SPS method was employed for the single-shot image acquisition.

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Experiment study on micro-structure on different crystallographic planes of mc-Si etched in alkaline solution

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Science China(Technological Sciences) 2012年第6期55卷 1509-1514页

作者： WANG KunXia FENG ShiMeng XU HuaTian TIAN JiaTong YANG ShuQuan HUANG JianHua PEI Jun Department of Physics Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Academy of Spaceflight Technology Shanghai 200235China Solarfun Power Holdings Solarfun Solar Shanghai Jiao Tong University R&D Center Shanghai 201109China Shanghai Shenzhou New Energy Source Development Co.Ltd Shanghai 20112China

The investigation of multi-crystalline silicon （mc-Si） surface etching technology is a key point in solar cell research. In this paper, mc-Si surface was etched in the common alkaline solution modified by an additive for 20 minutes at 78-80~C. Samples＇ surface morphology was observed by scanning electron microscope （SEM）. It is firstly found that the etched mc-Si surface has the uniform distribution of trap pits although the morphologies of trap pits are slightly different on different crystallographic planes. Si （100） plane was covered with many small Si-mountaln ranges or long V-shape channels arranged in a crisscross pat- tern. For （110） plane and （111） plane, they were full of a lot of triangle pit-traps （or quadrilateral holes） and twisted earthworm trap pits, respectively. The measured reflectance of the sample was 20.5% at wavelength range of 400--900 nm. These results illustrate that alkaline solution modified by an additive can effectively etch out trap pits with a good trapping light effect on mc-Si surfaces. This method should be very valuable for mc-Si solar cells.

关键词： mc-Si wafers chemical etching surface structure trapping effect reflectance

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development of large die fine pitch flip chip BGA using TCNCP technology

Development of large die fine pitch flip chip BGA using TCNC...

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Electronic Components and technology Conference (ECTC)

作者： Yanggyoo Jung Minjae Lee Sunwoo Park dongsu ryu Youshin Jung Chanha Hwang Choonheung Lee Sungsoon Park Miguel Jimarez Myung-June Lee Package Development Group R&D division Amkor Technology Korea Inc. Seoul Korea Amkor Technology Inc. Chandler AZ USA Altera Corporation San Jose CA USA

recently, technologies related to Fine Pitch Flip Chip or FPFC have been great achievements for various next generation devices, allowing a significant increase in the number of signal I/O and achieving low form factor packages. Consequently, fine pitch Cu pillar flip chip Chip Scale Package (CSP) with small sized die, with package dimension of less than 16×16mm, is already under high volume production using the Thermal-Compression Bonding with Non-conductive Paste (TCNCP) technology [1-2]. In the case of Flip Chip Ball Grid Array (FCBGA), there is a growing need for FPFC technology with Cu pillar in supporting next generation silicon node. However, there will be a high possibility of yield drop issue in conventional mass-reflow process and potential reliability due to the highly concerned tensile stress between low k die and substrate by CTE mismatch especially at the edge of the die. This can be a critical quality issue for fine pitch devices compared to normal pitch (i.e., 150um) flip chip BGA. Therefore, TCNCP bonding as an alternative should be studied on fine pitch Cu pillar flip chip BGA. This paper will discuss fine pitch flip chip assembly technology for large sized flip chip BGA. Two kinds of assembly method, mass reflow bonding versus thermal compression bonding, for the flip chip bonding will be compared for the large FPFCBGA package. Meanwhile, the advantage of TC bonding with pre-applied underfill process will be described. For robust interconnection between die and substrate for large FPFCBGA, the result of the bonding test will be described with several surface finishes such as ENEPIG, direct Immersion Gold (dIG), Immersion Tin (IT), and Solder Coating on substrate. Interestingly, one of selected surface finishes has shown excellent reliability test results. Finally, this paper will discuss an effective approach for fine pitch devices from an assembly perspective.

关键词： Flip chip Surface finishing Substrates Bonding reliability Tin

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Influence of drift region on the 1/f noise in LdMOS

Influence of drift region on the 1/f noise in LDMOS

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International Symposium on Power Semiconductor devices and Ics (ISPSd)

作者： A. A. dikshit V. Subramanian S. J. Pandharpure S. Sirohi T. J. Letavic Semiconductor R&D Center IBM India Pvt. Ltd Bangalore India Semiconductor R & D Center IBM India Pvt. Ltd Bangalore India Analog Mixed Signal Technology Development IBM Microelectronics Division Hopwell Junction NY USA

The effect of drift region on the flicker noise in LdMOS devices in the linear and saturation regions is analyzed using measured data and device simulations. In the linear region, noise in the drift region arises from gate-drain overlap region and is significant for longer channel length devices. For shorter channel length devices, the sub-surface current flow in the gate-drain overlap region reduces the contribution of noise from the drift region. In the saturation region, noise is dependent on quasi-saturation condition, and reaches its lowest value only when the channel is saturated.

关键词： 1f noise Logic gates Noise measurement MOSFET circuits Standards Immune system

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Characterisation of dSB-OCS technique for 40GHz radio over fibre system

Characterisation of DSB-OCS technique for 40GHz radio over f...

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Asia-Pacific Conference on Communications

作者： Syamsuri Yaakob Norhakimah Md Samsuri Nazif Farid romli Mohamad Amiza rasmi Muhammad Zamzuri Abdul Kadir Sevia Mahdaliza Idrus Shu-Hao Fan Advanced Physical Technology (APT) Telekom Research & Development (TM R&D) Cyberjaya Selangor Malaysia Facuhy of Electrical Engineering Universiti Teknologi Malaysia Johor Malaysia School of Electrical and Computer Engineering Georgia Institute of Technology Atlanta Georgia USA

The dual sideband optical carrier suppression (dSB-OCS) technique is characterised for its performance in order to be used as a carrier for 1.25Gbps OOK signal in the 40GHz radio over fibre (rOF) system. A dual electrode Mach-Zehnder modulator (dE-MZM) and the minimum transmission bias (MiTB) technique are employed to build the system. The results show that, a 40GHz carrier is successfully generated with the amplitude up to -29dBm and SNr of 35dB. Finally, an error free 40GHz rOF system is constructed with almost no penalty between the back to back and 20km fibre for a BEr of 10 -9 .

关键词： Optical fibers radio frequency Optical mixing Optical modulation Signal to noise ratio High speed optical techniques

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Optical Properties and Enhanced Photothermal Conversion Efficiency of SiO2/A-dlc Selective Absorber Films for A Solar Energy Collector Fabricated by Unbalance Sputter

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Physics Procedia 2012年 32卷 206-213页

作者： Fu-der Lai Wei-Yang Li C.Y. Huang Jui-Ming Hua Kai-Cheih Chang Ting-Pin Cho Yuen-Hsun Tsai Institute of Electro-Optical Engineering National Kaohsiung First University of Science and Technology Kaohsiung 811 Taiwan Department of Materials Engineering Tatung University Taipei 104 Taiwan Micro/Meso Mechanical Manufacturing R&D Department Metal Industries Research and Development Centre Kaohsiung 811 Taiwan

Solar energy could become the most attractive alternative energy source. In this study we test an attractive new candidate material for solar energy collectors. It can be found that the higher the gas pressure is, the higher the sp2/sp3 area ratio, the greater the sputtering rate and the greater the optical absorption. The photothermal conversion efficiency of a SiO2 coating on the amorphous diamond-like carbon (a-dLC) selective absorber films deposited on the Cr/mirror like Al substrate is 93.2% as the film thickness of a SiO2 coating is 105 nm. The coatings also increase the protective properties for a longer service life. This makes the SiO2 coated a-dLC film a promising new candidate material for solar selective absorber films. The SiO2/a-dLC selective absorber films also were deposited on the Al extrusion substrates.

关键词： selective absorber film solar energy collector amorphous carbon silicon oxide photothermal conversion efficiency

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design of traditional and a novel space-efficient antenna-coupling elements for lower LTE/GSM mobile phones

Design of traditional and a novel space-efficient antenna-co...

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Antennas and Propagation Conference, LAPC, Loughborough

作者： Aykut Cihangir Florence Sonnerat Fabien Ferrero Cyril Luxey romain Pilard Frédéric Gianesello Gilles Jacquemod LEAT-CREMANT-CNRS University Nice-Sophia Antipolis FRANCE STMicroelectronics Technology R&D Silicon Technology Development Crolles FRANCE Universite de Nice Sophia Antipolis Nice Provence-Alpes-Cote d'Azu FR IM2NP-CNRS UMR7334 University Nice-Sophia Antipolis Valbonne FRANCE

The mobile phone antennas exhibit a very low real impedance value especially in lower LTE (698-787MHz) and GSM (824-960MHz) bands, since the antennas are electrically small compared to operating wavelengths at these bands. Obtaining sufficiently low reflection coefficient and high TrP in a considerable bandwidth from such an antenna is very challenging without exciting proper currents on the PCB of the device. So the main trend for mobile handset antennas has moved toward using an electrically-small coupler plate to excite those PCB currents. In this way, the input impedance of the coupling element-chassis combination has a relatively high real part and the quality factor of the system is now much more lower than traditional resonant antennas, enabling higher bandwidth potential with the help of a proper matching network. In this paper, this approach is followed to cover lower LTE (698787MHz) and GSM (824-960MHz) standards with a novel hollow coupling element antenna while keeping space available around and inside the antenna, for additional components or even another higher band antenna (dCS/PCS and UMTS).

关键词： Couplings Antenna measurements Mobile antennas reflector antennas Broadband antennas

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