http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Substrate effects on the microstructure of hydrogenated amorphous carbon films
I. Ahmad,S.S. Roy,Md.A. Rahman,T.I.T. Okpalugo,P.D. Maguire,J.A. McLaughlin 한국물리학회 2009 Current Applied Physics Vol.9 No.5
In this work, plasma enhanced chemical vapour deposition was used to prepare hydrogenated amorphous carbon films (a-C:H) on different substrates over a wide range of thickness. In order to observe clear substrate effect the films were produced under identical growth conditions. Raman and near edge X-ray absorption fine structure (NEXAFS) spectroscopies were employed to probe the chemical bonding of the films. For the films deposited on silicon substrates, the Raman ID/IG ratio and G-peak positions were constant for most thickness. For metallic and polymeric substrates, these parameters increased with film thickness, suggesting a change from a sp3-bonded hydrogenated structure to a more sp2 network, NEXAFS results also indicate a higher sp2 content of a-C:H films grown on metals than silicon. The metals, which are poor carbide precursors, gave carbon films with low adhesion, easily delaminated from the substrate. The delamination can be decreased/eliminated by deposition of a thin ( ~10 nm) silicon layer on stainless steel substrates prior to a-C:H coatings. Additionally we noted the electrical resistivity decreased with thickness and higher dielectric breakdown strength for a-C:H on silicon substrate.
A. Mathur,S.S. Roy,M. Tweedie,S. Mukhopadhyay,S.K. Mitra,J.A. McLaughlin 한국물리학회 2009 Current Applied Physics Vol.9 No.6
In this study we fabricated a silicon-based stamp with various microchannel arrays, and demonstrated successful replication of the stamp microstructure on poly methyl methacrylate (PMMA) substrates. We used maskless UV lithography for the production of the micro-structured stamp. Thermal imprint lithography was used to fabricate microfeatured fluidic platforms on PMMA substrates, as well as to bond PMMA lids on the fluidic platforms. The microfeature in the silicon-based (silicon wafer coated with SU- 8) stamp includes microchannel arrays of approximately 30 ㎛ in depth and 5 mm in width. We produced various channels without pillars, as well as with SU-8 pillars in the range of 50–100 ㎛ wide and 6 ㎛ in height. PMMA discs of 1 mm thickness were utilized as the molding substrate. We found 10 kN applied force and 100 ℃ embossing temperature were optimum for transferring the microstructure to the PMMA substrate. In this study we fabricated a silicon-based stamp with various microchannel arrays, and demonstrated successful replication of the stamp microstructure on poly methyl methacrylate (PMMA) substrates. We used maskless UV lithography for the production of the micro-structured stamp. Thermal imprint lithography was used to fabricate microfeatured fluidic platforms on PMMA substrates, as well as to bond PMMA lids on the fluidic platforms. The microfeature in the silicon-based (silicon wafer coated with SU- 8) stamp includes microchannel arrays of approximately 30 ㎛ in depth and 5 mm in width. We produced various channels without pillars, as well as with SU-8 pillars in the range of 50–100 ㎛ wide and 6 ㎛ in height. PMMA discs of 1 mm thickness were utilized as the molding substrate. We found 10 kN applied force and 100 ℃ embossing temperature were optimum for transferring the microstructure to the PMMA substrate.
Effect of thin aluminum interlayer on growth and microstructure of carbon nanotubes
A. Mathur,S.S. Roy,C. Dickinson,J.A. McLaughlin 한국물리학회 2010 Current Applied Physics Vol.10 No.2
The aluminum (Al) interlayer with various thicknesses ranging from 0.75 to 6 nm was deposited on silicon (Si) substrates prior to the deposition of ultra-thin iron (Fe) catalyst for the growth of carbon nanotubes. In this paper we report the effect of ultra-thin Al interlayer on the growth of multiwalled carbon nanotubes (MWCNTs). The SEM was used to examine the microstructures of nanotubes. We observed as the Al interlayer thickness increases the height of nanotube decreases. Raman spectra of MWCNT showed typical D and G peaks at ~1345 cm-1 and ~1575 cm-1, respectively. The XPS revealed the presence of Al and Fe on the top of CNT surface which were further supported by TEM. The high resolution TEM results also revealed bamboo like CNTs with diameter ~10–40 nm.
Jennifer M. Brewer,Owen P. Karsmarski,Jeremy Fridling,T. Russell Hill,Chasen J. Greig,Sarah E. Posillico,Carol McGuiness,Erin McLaughlin,Stephanie C. Montgomery,Manuel Moutinho,Ronald Gross,Evert A. E The Korean Society of Traumatology 2024 大韓外傷學會誌 Vol.37 No.1
Purpose: Research on rib fracture management has exponentially increased. Predicting fracture patterns based on the mechanism of injury (MOI) and other possible correlations may improve resource allocation and injury prevention strategies. The Chest Injury International Database (CIID) is the largest prospective repository of the operative and nonoperative management of patients with severe chest wall trauma. The purpose of this study was to determine whether the MOI is associated with the resulting rib fracture patterns. We hypothesized that specific MOIs would be associated with distinct rib fracture patterns. Methods: The CIID was queried to analyze fracture patterns based on the MOI. Patients were stratified by MOI: falls, motor vehicle collisions (MVCs), motorcycle collisions (MCCs), automobile-pedestrian collisions, and bicycle collisions. Fracture locations, associated injuries, and patient-specific variables were recorded. Heat maps were created to display the fracture incidence by rib location. Results: The study cohort consisted of 1,121 patients with a median RibScore of 2 (range, 0-3) and 9,353 fractures. The average age was 57±20 years, and 64% of patients were male. By MOI, the number of patients and fractures were as follows: falls (474 patients, 3,360 fractures), MVCs (353 patients, 3,268 fractures), MCCs (165 patients, 1,505 fractures), automobile-pedestrian collisions (70 patients, 713 fractures), and bicycle collisions (59 patients, 507 fractures). The most commonly injured rib was the sixth rib, and the most common fracture location was lateral. Statistically significant differences in the location and patterns of fractures were identified comparing each MOI, except for MCCs versus bicycle collisions. Conclusions: Different mechanisms of injury result in distinct rib fracture patterns. These different patterns should be considered in the workup and management of patients with thoracic injuries. Given these significant differences, future studies should account for both fracture location and the MOI to better define what populations benefit from surgical versus nonoperative management.