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Wire Diameter (wire + diameter)
Selected AbstractsSolenoidal microcoil design,Part II: Optimizing winding parameters for maximum signal-to-noise performanceCONCEPTS IN MAGNETIC RESONANCE, Issue 3 2001Kevin R. Minard Abstract In high-field proton NMR, the signal-to-noise ratio (SNR) achieved with a close-fitting solenoidal microcoil is adversely affected by radio frequency (RF) losses in the coil, its leads, the capacitor used to tune it, and finally, the sample. In Part II, a rigorous description of these various losses is presented, and their severity is related to the details of coil design. Results not only provide a rational basis for defining a microcoil's optimal wire diameter and the number of turns, but also for evaluating how the SNR varies with coil size and NMR frequency in high-field proton NMR studies involving either conducting or non-conducting samples. © 2001 John Wiley & Sons, Inc. Concepts Magn Reson 13: 190,210, 2001 [source] Theoretical investigation of elastic flexural properties for multistranded orthodontic archwiresJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 3 2002Brian K. Rucker Abstract The bending and torsional stresses during flexure were detailed and simplified for a single twisted strand, which emulates a spring. General expressions were derived to evaluate the elastic properties (i.e., strength, stiffness, and range) of multistranded wires by combining the effects of a number of outer twisted strands, with or without an inner strand. Specific expressions were solved for single-stranded, twisted, and coaxial wires. Initially, we considered the following multistranded wire configurations: two- (twin), three- (triple), four-strand (quad) twisted, and coaxial wires. The elastic properties of the twin and quad wires were essentially subsets of the triple wire. For a given overall wire diameter (D) and helix angle (,), the ranges of multistranded wires were independent of wire configurations. By varying the , from 45 to 85°, the D from 0.394 to 0.546 mm (15.5 to 21.5 mil), and the stress at the proportional limit from 1.03 to 3.28 GPa (150 to 475 ksi), the theoretical elastic properties of triple and coaxial stainless steel wires matched many of the properties of conventional nickel titanium leveling wires. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62: 338,349, 2002 [source] Circular wire loop antenna with stepped wire diameterMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2002H. Scott Abstract A circular wire-loop antenna of 1.042,0 circumference at 1 GHz with 4:1 balun and stepped wire diameter is presented in this Letter. A fixed E -field beam offset from broadside of ,7.5° is demonstrated with a VSWR of 1.17 at 1 GHz. The antenna has an operational bandwidth of 29% for VSWR < 2 and an estimated gain of 1.24 dB. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 14,15, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10358 [source] Optical properties of single ZnO nanowiresPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 4 2006L. Wischmeier Abstract The optical properties of single ZnO nanowires with diameters <200 nm are analyzed. A comparison of the photoluminescence properties of the as-grown ensemble and of an individual nanowire is given. The temperature dependence of the individual nanowire photoluminescence shows the same behavior as that of bulk material due to the wire diameter being very large compared to the exciton Bohr radius of ZnO. Furthermore, high excitation-density measurements performed on an individual nanowire are presented in which a sharp line is observed resulting from resonator effects inside the wire. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Densely Packed Arrays of Ultra-High-Aspect-Ratio Silicon Nanowires Fabricated using Block-Copolymer Lithography and Metal-Assisted EtchingADVANCED FUNCTIONAL MATERIALS, Issue 15 2009Shih-Wei Chang Abstract Metal-assisted etching is used in conjunction with block-copolymer lithography to create ordered and densely-packed arrays of high-aspect-ratio single-crystal silicon nanowires with uniform crystallographic orientations. Nanowires with diameters and spacings down to 19,nm and 10,nm, respectively, are created as either continuous carpets or as carpets within trenches. Wires with aspect ratios up to 220 are fabricated, and capillary-induced clustering of wires is eliminated through post-etching critical point drying. The wires are single crystals with ,100, axis directions. The distribution of wire diameters is narrow and closely follows the size distribution of the block copolymer, with a standard deviation of 3.12,nm for wires of mean diameters 22.06,nm. Wire arrays formed in carpets and in channels have hexagonal order with good fidelity to the block copolymer pattern. Fabrication of wires in topographic features demonstrates the ability to accurately control wire placement. Wire arrays made using this new process will have applications in the creation of arrays of photonic and sensing devices. [source] | ||||||||||