... rolls and guillotine blade in the one machine 5.10A Undertake Fabrication, Forming, Bending and Shaping Folding Machines Bar bender This machine is used to bend flat and round bars by hand ... for weld procedures and testing Straightening of small jobs Cutting keyways Removing bearings and bushes from shafts 5.10A Undertake Fabrication, Forming, Bending and Shaping Folding Machines ... Standard dies available include: Knife and vee Acute angle knife and vee Special purpose blocks and dies depending on the shape (form) of the bent article Dies and blocks can be manufacture to...
Ngày tải lên: 16/02/2017, 21:01
COMBINED BENDING AND DIRECT STRESS
... 37.5 cm and 75 cm and the material is 2.5 cm thick all round, and the longer dimension is in the direction AB Calculate the maximum tensile and compressive stresses set up in the section, and locate ... cross-section m by m ,and is subjected to a load of 1000 kN, the line of the resultant being 1.80 m from one of the shorter sides, and 0.85 m from one of the longer sides Find the maximum tensile and compressive ... through the beam and anchored at each end Further problems (answers on page 693) 12.3 The single rope of a cantilever crane supports a load of 200 kN and passes over two pulleys and then vertically...
Ngày tải lên: 08/04/2014, 11:27
... it, “Like a poem, x Introduction a genuine essay is made out of language and character and mood and temperament and pluck and chance.” Creative nonfiction can focus on either private experience ... understanding —Kim Barnes, author of IN THE WILDERNESS and HUNGRY FOR THE WORLD My brother is swinging the bat and I’m bored in the stands, seven years old My mother has given me a piece of paper and ... common and very important characteristic: they get somewhere, and they summon you there, and you feel, not with your mind, but with your whole being, that they have a certain purpose and, like...
Ngày tải lên: 09/05/2014, 12:44
Novel methods (sonochemistry, microwave dielectric heating, sonoelectrochemistry and RAPET for the fabrication of nanomaterials and their applications
... that determine the particle size in sonoelectrochemistry are temperature, sonication intensity, and the electric pulse width Its main synthetic advantage is the ability to reduce metals for which ... For example, preparing metallic Mg nanoparticles.The last technique was named by us RAPET It stands for Reaction under Autogenic Pressure at Elevated Temperatures RAPET is being used in our laboratory...
Ngày tải lên: 11/06/2014, 12:29
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 1 ppt
... adapt to metallic and non-metallic surfaces alike, and also generate 3-D features and/ or free-form sculpted surfaces However, the challenges of achieving accuracy, precision and resolution persist ... to download, copy and build upon published chapters even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact ... Mohammad Yeakub Ali, Reyad Mehfuz, Ahsan Ali Khan and Ahmad Faris Ismail Chapter Mechanical Micromachining by Drilling, Milling and Slotting 159 T Gietzelt and L Eichhorn Chapter Release Optimization...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 3 doc
... photothermal (purely pyrolytic), photochemical (purely photolytic), and photophysical processes, in which both thermal and non -thermal mechanisms contribute to the overall ablation rate 2.3 Thermal ... chambers, mixers, and manifolds, along with some moving mechanical components such as valves, pumps, and injectors, and often some optical and electrical components for integrated control and sensing ... fluorescence band: from ~670 nm to ~1090 nm For efficient pumping, it needs to be optically excited in its absorption band, which is centered about 500 nm, and for which argon ion lasers and frequency...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 4 pot
... computing the average ablation depths and standard deviation, the depth of laser micromachining can be characterized as: Average depth (mean) standard error (=2.58 standard deviation/ square root(sample ... power and efficiency, and robust operation over a long service life They are routinely applied to an extremely wide range of material processing, including scribing, marking, drilling, cutting, and ... ablation processes, thermal and photochemical, are determined by the materials properties Figure 14 depicts the absorption coefficients of transparent materials, sapphire and Pyrex, and Table shows...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 6 docx
... CHF3/Ar and C2ClF5/Ar plasmas, for example, can achieve an etch rate between 60 and 470 angstrom/min (Liann-Be, et al 2001) Inductively coupled plasma (ICP) etching using Cl2 and Ar, on the other hand, ... to decompose into liquid Ga and N2 gas at a temperature of 900C (Choi, et al 2002) The rapid heating and cooling cycles in air can result in the increased generation and resolidification of molten ... of rapid heating and cooling is the increased thermal stress incurred in the crystal structure of GaN Cracks may be resulted 104 Micromachining Techniques for Fabrication of Micro and Nano Structures...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 7 docx
... representations: Beer’s law and the Srinivasan-Smrtic-Babu (SSB) model [Shin, et al., 2007], which are based on pure photochemical and combination of photochemical and photothermal mechanisms respectively ... medium (solid, liquid and gas), output power (low, medium and high power lasers), excitation method (electrical, optical and chemical), operating mode (continuous wave, pulsed mode and Q-switched output ... is compatible with the standard processes employed in PCB manufacturing such as soldering temperature, Coefficient of Thermal Expansion (CTE) matching, thermal stability and stress during lamination...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 9 docx
... lapping, and processes are using defined cutting edges like drilling, milling and slotting Especially grinding works at high cutting rates Most of the cutting energy is transferred into heat and absorbed ... for cooling and lubrication to reduce the friction of the cutting edge with the work piece material and to decrease the thermal load of the cutting edge connected with increased wear and diffusion ... slotting is slow Hence, also the cutting temperatures are low and monocrystalline tools can be used also for ferrous materials 2.3 Thermal aspects, lubrication and cooling Mechanical machining...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 10 docx
... machine and the materials used also have an impact on thermal stability For the machine bed, KERN uses polymer concrete with a low thermal coefficient of expansion of 10-20*E-06/K [Epu_Cr] and much ... Drilling, Milling and Slotting 173 rack and high-strength aluminium is used for the spindle clamping, the shape and fixing position of the clamping to the machine have a high impact on thermal drift ... suppliers use granite and a portal architecture for their machines [Kug_Mg, Ltu] for low thermal shift 4.3.2 Clamping and measurement of micro end mills The detection of tool length and tool diameter...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 11 pot
... micro-scale With that understanding, we chose the practical and rather loose definition of meso- and micro-scale for features between 100 μm and 250 µm and less than and equal to 100 μm, respectively ... that involves fluid-fluid (air and water), fluid-solid (air, water, and abrasives), and solid-solid (abrasives and materials) interactions During piercing and cutting, the complex flow is confined ... on a cutting model (e.g., Zeng & Kim, 1995) and a set of parameters (including nozzle size and pressure; abrasive type, size, and flow rate; material type; path geometry; part thickness; and edge...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 12 docx
... an efficient and costeffective precision AWJ machine R&D and beta miniature AWJ nozzles, with and without ancillary devices, have been developed for meso- and micro-scale test cutting Success ... garnet because of its optimum performance of cutting power versus cost and its lack of toxicity It is also a good compromise between cutting power and wear on carbide mixing tubes There are two ... programming and controller memory Instead, the power and memory of the modern PC is used to compute and store the entire tool path and feed rate profile and then directly drive the servomotors that control...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 13 potx
... nature and thermal analysis and material removal are considered to be due to this thermal source (Jain et al.,1999; Basak & Ghosh, 1992) Experimentally it has been found that the spark is a non thermal ... 08-02, 09-02, and 10-02 Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and not necessarily reflect the views of the NSF and PNNL Contributions ... process thought of and being researched is electrochemical spark micromachining (ECSMM) process The ECSMM process is a stand alone process unlike others and it does not demand on intermediate...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 14 ppt
... Dixit, P.M and Pandey, P.M (1999) On the analysis of electro chemical spark machining process’, Int J of Machine Tools and Manufacture, Vol 39, pp.165–186 Kulkarni, A V., Jain, V.K and Misra, ... micromachining (microchannels and microholes) of metals and non-metals, Int J Manufacturing Technology and Management, vol 22, no 2, 107-123 Kulkarni A V., Jain V K., and Misra K A., (2010c) Development ... Fabrication of Micro and Nano Structures Wuthrich, R., Fascio, V., Viquerat, D and Langen, H (1999) ‘In situ measurement and micromachining of glass’, Int Symposium on Micromechatronic and Human Science,...
Ngày tải lên: 21/06/2014, 02:20
Micromachining Techniques for Fabrication of Micro and Nano Structures Part 16 pptx
... Modeling and Simulation of MEMS Components: Challenges and Possible Solutions Physical Phenomenon MEMSMEMS type Electromagnetism Thermal and Mechanical Electrothermal Actuators (ETA) Electrical, Thermal ... is thermal diffusivity , Q heat generation term, ρ is the density and C is the specific heat of the medium Thermal boundary conditions These conditions can be obtained from the prevailing thermal ... (11) E E t (12) in which E and H are electric and the magnetic field vectors, and , , are respectively the permittivity, the permeability and the conductivity of the material (medium)...
Ngày tải lên: 21/06/2014, 02:20
MICROMACHINING TECHNIQUES FOR FABRICATION OF MICRO AND NANO STRUCTURES pptx
... (TFT) devices including interferometers and gratings by FIB micromachining and their characteristics and sensing applications Fabrication and measurement Standard optical TFT is an optical microfiber ... chambers, mixers, and manifolds, along with some moving mechanical components such as valves, pumps, and injectors, and often some optical and electrical components for integrated control and sensing ... energy & kBT is thermal energy These applications include electric-field sensors Focused Ion Beam Based Three-Dimensional Nano-Machining 11 and quantum current standards (Bylander, 2005) In long...
Ngày tải lên: 27/06/2014, 01:20
creating and shaping texts ages 8-9
... length and number of lines, rhyme pattern and rhythm) and provides models and ideas to help the children write poems with different forms: prayers, a ballad with a repeated chorus and a question -and- answer ... Develop and refine ideas in writing using planning and problem-solving strategies Organisation • Use settings and characterisation to engage readers’ interest • Summarise and shape material and ideas ... provide learning activities to support strands and of the literacy objectives of the Primary Framework for Literacy: Creating and shaping texts and Text structure and organisation The structure of 100%...
Ngày tải lên: 03/11/2014, 07:12
Fabrication, surface modification and growth factor encapsulation of polymeric microspheres as scaffold for liver tissue regeneration
... in 1987 and defined as “the application of the principles and methods of engineering and life sciences toward the fundamental understanding of structure-function relationships in normal and pathological ... xenogeneic and stem cell), and manipulation of cell proliferation and functions; (2) designing a 3D substrate which allows the cells to organize and remodel to develop into tissue-like constructs; and ... requirements: (1) suitable structure and shape, (2) large surface to volume ratio and porosity, (3) appropriate mechanical and surface properties, and (4) biodegradability (Freed and Vunjak-Novakovic, 1998;...
Ngày tải lên: 12/09/2015, 08:18