materials their properties and uses

... synthesis, properties and uses of carbon materialswith helical morphology Ahmed Shaikjee a,b, Neil J Coville a,b,* a DST/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, ... cellular keypads)[16] It is expected that nano materials with helical morphology should possess both similar and unique physical and chemical properties to their macro components Nano helices should ... helical carbon materials are observed to form un-der a wide range of temperatures and pressures, and in thepresence of numerous reactive agents and catalysts Thesestudies, listed inTables 1 and 2, have...

Ngày tải lên: 13/01/2020, 12:17

... steels – their properties and their suitability for welding Interim reprint omslag 1o4,2o3 02-06-27 07.36 Sida 2 The revisions made to this brochure concern the cover, company name and logotype ... of microstructure for the corrosion resistance properties, physical proper- ties and mechanical properties of the steels and provide information on their weldability – give advice on the selection ... chemical industry and the food processing industry. The molybdenum-free steels also have very good high-temperature properties and are therefore used in furnaces and heat exchangers. Their good impact...

Ngày tải lên: 14/03/2014, 12:21

... metal oxides stand out as one of the mostversatile materials, owing to their diverse properties and functionalities Their Q1D structures not onlyinherit the fascinating properties from their bulk ... 1Quasi-one-dimensional metal oxide materials—Synthesis,properties and applications Jia Grace Lu * , Paichun Chang, Zhiyong Fan Department of Chemical Engineering and Materials Science & Department ... metaloxide materials, such as ZnO, In2O3, Ga2O3, SnO2, Fe2O3, Fe3O4, CuO, CdO, TiO2 and V2O5.Based on these fundamental physical properties, the recent progress of Q1D functional elementsand their...

Ngày tải lên: 20/03/2014, 13:06

... The book ‘Crystalline Silicon: Properties and Uses’ presents fifteen chapters in all with the examples of different forms of silicon material, their properties and uses. Formation of silicon thin ... Silicon – Properties and Uses Brus, 19 94; Alivisatos, 19 96) and experimentally explored as follows: (a) 0D and 1D materials as visible-near IR emitters, including nc-Si and nanoparticles ... CRYSTALLINE SILICON – PROPERTIES AND USES Edited by Sukumar Basu Crystalline Silicon – Properties and Uses Edited by Sukumar Basu Published...

Ngày tải lên: 19/06/2014, 19:20

... (left) and PL spectra (right) of n-BSNP and n-BGNP films excited at 365 nm at 77 K By analogy with the SNPs described above,GNP may have potential uses as NIR emitters and narrow band gap materials ... inorganic materials makes it possible to tailor the band gap value, as shown in Table 1 Soluble SNP and GNP, because of their ease of coating and dispersion in the form of "Si-ink" and "Ge-ink", ... Si-/Ge-source materials for the production of variable range Si-based and/or Si-Ge alloyed semiconductors at room temperature The ionization potential of the pyrolyzed Si materials range between 5.2 and...

Ngày tải lên: 19/06/2014, 19:20

... utilized to establish their relations to dislocations. Lines D1 and D2, on the one hand, and lines D3 and D4, on the other, show similar shifts by applying uniaxial stress and therefore have been ... spectrum shows the presence of dislocation-induced D-bands (D1 – D4) besides the band-band luminescence (BB). Crystalline Silicon – Properties and Uses 66 dislocations in epitaxially grown SiGe ... Crystalline Silicon – Properties and Uses NEUTRAL PARTICLES Fig 3 a) Diffusion process is in thermodynamic equilibrium and energies are thermal (~eV) and random (isotropic) CHARGED...

Ngày tải lên: 19/06/2014, 19:20

... SIMS profiles for B and B18 implants. #03-0C #08-0C #09-0C Annealed Fig. 17. Annealed SIMS profiles for B and B18 implants. Crystalline Silicon – Properties and Uses 96 Table ... material was reconstructed and returned to its... principle of ellipsometry measurement is presented 106 Crystalline Silicon – Properties and Uses Fig 1 Reflection and transmission of ... integration. Crystalline Silicon – Properties and Uses 90 Fig. 9. Sheet resistance vs. junction depth as a function of ramp rate, implantation dose and implantation energy. Note the similarity...

Ngày tải lên: 19/06/2014, 19:20

... high level and the resulting high accuracy of their calculations have led to the resolution of existing experimental and theoretical discrepancies Their results also clarify unambiguously and confirm ... oxygen contamination on the optical properties of 1nm nanoparticles and its possible contribution to their experimentally observed absorption and emission properties By performing the same method, ... interested in the theoretical study on the band gap and the optical spectrum with respect to the size of the Si-NCs or Si-QDs and surface terminations and reconstructions The effective mass approximation...

Ngày tải lên: 19/06/2014, 19:20

... Stanisic G and Popovic Z : Photoluminescence properties of silica aerogel during sintering process, J Sol-Gel Science and Technology 14 (1999) 281 Trang 3Crystalline Silicon – Properties and Uses ... C N , Im S and Song J H : Violet and orange luminescence from Ge-implanted SiO 2 layers, Materials Science and Engineering B 69-70 (2000) 474 Lide D R : CRC Handbook of Chemistry and Physic, ... Peng J L and Bursill L A : Joint Density of States of Wide-Band-Gap Materials by Electron Energy Loss Spectroscopy, Modern Phys Lett B 12 (1998) 541 Fanderlik I (ed.) : Silica Glass and its...

Ngày tải lên: 19/06/2014, 19:20

... There, a model and respective rate equations are given for the temperature and dose dependence of both the red R and the blue B bands The association of mobile oxygen to the E´-centers and re-creation ... bands at 295 nm (4.2 eV) and 410 nm (3.1 eV) respectively, and a green band around 535 nm (2.3 eV) are seen predominantly on non-annealed samples even at low temperature The well-known red band ... luminescence in wet oxide SiO2, where hydrogen and hydroxyl are present 1200 Y: 565 nm , at LNT Fig 3.4 The dose-dependent of the yellow band Y (top) and the red band R (bottom) in SiO2:H at different...

Ngày tải lên: 19/06/2014, 19:20

... , Lee C S and Lee S T.: Large-Scale Rapid Oxidation Synthesis of SnO 2 Nanoribbons, J Phys Chem B 106 (2002) 3823 Hu J Q , Bando Y and Golberg D : Self-catalyst growth and optical properties ... Iacona F., Franzo G and Spinella C : Correlation between luminescence and structural properties of Si nanocrystals, J Appl Phys 87 (2000) 1295 Ivanda M , Clasen R , Hornfeck M and Kiefer W : Raman ... 1997) and in the handbook on Porous Silicon properties edited by Canham (Canham, 1997a) H Foll et al (Foll et al 2002) and V Parkhutik (Parkhutik, 1999) also elaborately reviewed the formation and...

Ngày tải lên: 19/06/2014, 19:20

... vacancies and dangling bonds that can play an important role in the transport properties of electrons of nano materials As the grain boundaries are metastable states they want to reduce their energy ... In: Properties of porous silicon Canham L (ed): pp 38-43 and 127-131 INSPEC, London Ben-Chroin, M (1997) Resistivity of porous silicon In: Properties of porous silicon Canham L (ed) pp 38-43 and ... Carstensen, J & Hasse, G (2002) Formation and application of porous silicon, Materials Science and Engineering R Vol 39, pp 93 Fuchs, HD., Stutzmann, M., Brandt, MS., Rosenbauer, M., Weber, J &...

Ngày tải lên: 19/06/2014, 19:20

... (2004) Optical properties of porous silicon (Part I) - Fabrication and investigation of single layers, Optical Materials 25(3): 251-255 Lehmann V., Föll, H (1990) Formation Mechanism and properties ... detectors, and so on More than a simple ensemble of devices, this is a new research field that combines the properties and characteristics of different materials to find innovative and affordable ... electrical conductivity and therefore improve the conversion efficiency ofhybrid devices.7 Acknowledgments Antonio del Rio and Hailin Hu from CIE-UNAM by their advice, and IACOD-DGAPA(I1102611...

Ngày tải lên: 19/06/2014, 19:20

... 1.3 and 2.7 t CO2/kW, and. .. Technology; 42 (6): 2,168 – 2,174 304 Crystalline Silicon – Properties and Uses Life-cycle atmospheric Cd emissions for PV systems from electricity and ... Silicon – Properties and Uses 298 assumptions, data availability and accuracy. Hence, it is impossible to generalize the method in a very clear way. As a result, LCA operators and users ... understand the limitations of LCA and the assumptions that can be drawn from its results. The essentials of LCA are standardized in ISO 14040 and ISO 14044, which stipulate the details and basic...

Ngày tải lên: 19/06/2014, 19:20

... diaphragm and back plate electrode, resist (AZ1500) as a sacrificial layer, and sputtered silicon oxide as an insulation layer The whole process sequence uses three masks and several deposition, and ... Integration, and Packaging of MEMS/MOEMS, Paris Ganji, B A and Majlis, B Y (2009) Design and fabrication of a new MEMS capacitive microphone using a perforated aluminum diaphragm Sensors and Actuators ... effect of residual stress and stiffness of diaphragm and also includes some acoustic holes to reduce air damping in the gap By this way, the microphone size was reduced, and the sensitivity was...

Ngày tải lên: 19/06/2014, 19:20

... Trang 1MOULDS AND MATERIALS With the exception of admixtures and fly ash, all moulds and materialsare discussed in this chapter None of the factors ... moulding materials as it is relatively cheapcompared to other choices and is easy to cut and shape It is also Trang 5available in forms such as plywood and chipboard which haveadvantages and disadvantages ... carcinogenic and/or dermatitic and personal cleanliness andprotection are essential Second, fine air sprays giving a mist should beavoided as they can become airborne and be inhaled, and there is...

Ngày tải lên: 08/08/2014, 10:23

... setting and hardening rates of cement for the main purpose in precast work of getting a faster turnover Trang 2rate in demoulding and stacking and faster delivery times The most common and the ... Calcium formate, sodium nitrite and others are not so effective as calcium chloride and are extremely sensitive in their performance to the chemistry of the Portland cement This is particularly ... cement, and ordinary Portland cements with levels of C3A well under 10% and sulphate-resisting cements are the only types that will apparently benefit The choice is between the use of plasticising and...

Ngày tải lên: 08/08/2014, 10:23

... reinforcement, fittings, fixings and expanded plastics sandwiches should be included. Sandwich panels should be true sandwich units and not bridged as the different curing conditions and temperatures will ... the desk-top 100mm square sample and the 300mm square hand- portable samples are misleading in the case of unpigmented materials, and for coloured concretes and mortars they seldom resemble the ... oxides and hydroxides with those based upon iron furnishing yellow, brown, black and red colours and mixtures thereof. Chromic oxide and hydroxide give green colours, cobaltic oxide blue and titanium...

Ngày tải lên: 08/08/2014, 10:23

... (long-term cementitious effect in the presence oflime and water) and exotherm control properties, as well as its ability togive ordinary Portland mixes an improved sulphate resistance, have beenused ... minute old) handlingproperties? (b) Does the addition improve the early strength (6–18 hours old)?(c) Has the product better surface appearance and arrisses? (d) How are other relevant properties ... all their other properties may be acceptable This isshown in Fig 4.1 in five-year-old kerbs.Carbon is found as angular soft black particles which act as nominalvoids and create a high water demand...

Ngày tải lên: 08/08/2014, 10:23

... of manpower, materials and plant It is also beneficial to have qualified technical staff to advise existing and potential clients and to visit sites to advise clients and avoid and/or deal with ... subject to down-time cleaning and, if necessary, oiling, at the end of each working period 5.9 HANDLING AND CRANAGE Products may be manually, machine or truck handled and great care is necessary ... Some Portland cements are liable to flash setting at concreting temperatures of 40°C and above, and cooling in a hot climate can be as expensive as heating in a cold climate Stocking and re-stocking...

Ngày tải lên: 08/08/2014, 10:23