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Blocks Used (block + used)
Selected AbstractsCarbon-Nanotube-Based Electrical Brush ContactsADVANCED MATERIALS, Issue 20 2009Geza Toth Electrical properties of brush contacts made of bulk carbon nanotube forest are significantly better than the presently used commercial products due to the unique and intimate surface interaction of the former on the nanoscale. The image displays the nanotube block used, the measurement setup, and the resistance fluctuations for the carbon nanotube and the conventional brush setups. [source] A new technique for non-destructive field measurement of rock-surface strength: an application of the Equotip hardness tester to weathering studiesEARTH SURFACE PROCESSES AND LANDFORMS, Issue 12 2007Hisashi Aoki Abstract Tafone-like depressions have developed on the Aoshima sandstone blocks used for a masonry bridge pier in the coastal spray zone. A thin layer of partial granular disintegration was found on the surface in depressions. To evaluate quantitatively the strength of the thin weathered layer, the hardness was measured at the surface of the sandstone blocks using both an Equotip hardness tester and an L-type Schmidt hammer. Comparison of the two testing results indicates that the Equotip hardness value is more sensitive in evaluating the strength of a thin layer of weathered surface rock than the Schmidt hardness value. By applying two methods, i.e. both the repeated impact method and the single impact method, the Equotip tester can evaluate the strengths of fresh internal and weathered surficial portions of rocks having a thin weathering layer. Comparison of the two strengths enables evaluation of strength reduction due to weathering. Copyright © 2007 John Wiley & Sons, Ltd. [source] Synthesis and characterization of 2,2-bis(methylol)propionic acid dendrimers with different cores and terminal groupsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 7 2004Michael Malkoch Abstract Three sets of aliphatic polyester dendrimers based on 2,2-bis(methylol)propionic acid (bis-MPA) were synthesized. Two of the sets had benzylidene terminal groups and either a trimethylolpropane or triphenolic core moiety. The last set had acetonide terminal groups and a triphenolic core moiety. Benzylidene-[G#1]-anhydride and acetonide-[G#1]-anhydride were used as the reactive building blocks in the construction of all dendrimers. The large excess of building blocks used in the coupling reactions initially resulted in considerable material loss. This waste was eliminated through the development of a recycling method. 1H and 13C NMR and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) analysis were used to verify the purity of all compounds. Size exclusion chromatography (SEC) was used, as well as MALDI-TOF, for molecular weight determinations. The SEC measurements were conducted with a universal calibration method and an online right-angle laser light scattering detector. Measured dendrimer molecular weights were close to their theoretical molar masses. Observations were also made of the hydrodynamic radius and intrinsic viscosity for the different dendrimers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1758,1767, 2004 [source] Ultrasonographic guidance in pediatric regional anesthesia.PEDIATRIC ANESTHESIA, Issue 11 2006Part 2: techniques Summary The benefits of regional anesthesia are well documented. The downsides of such techniques have been a significant failure rate and a potential for serious complications. Nearly, all regional blocks were first described as essentially ,blind' techniques. The development of high-resolution portable ultrasound (US) has made the use of US for regional anesthesia possible. Improved understanding of sonographic anatomy should lessen both the failure rate and the possibility of incurring serious complications. Natural caution has dictated that only a selection of blocks used in adults has been commonly used in pediatric practice, but with the aid of US, the repertoire of blocks for infants and children may be widened. The second part of this review will concentrate on the practice of both peripheral and central blocks. [source] | ||||||||||