Academic literature on the topic 'Bulb thickness'
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Journal articles on the topic "Bulb thickness"
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Suhonen, Irma, and Leena Kokkonen. "The effect of planting date on growth, seed stalk development and yield of sweet fennel." Agricultural and Food Science 62, no. 3 (1990): 237–44. http://dx.doi.org/10.23986/afsci.72930.
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To study the growth and development of sweet fennel (‘ZEFA-Fino’ and ‘ZEFA-Tardo’) seedlings were raised under greenhouse conditions (night temperature 16—18°C) and planted out at 3—4 true leaf stage on May 21st, June 10th, July 7th and July 27th. The effects of covering mulch and short day treatment of seedlings were studied also. First harvests were performed when field measurements showed that the greatest width of ‘ZEFA-Fino’ bulbs were on average 60 mm. Three harvests were then performed at one week intervals. Plant and bulb weights, bulb greatest width and thickness and, the heights of plant, bulb and stem inside the bulb was measured. The number of bolters were recorded. The bulb width of ‘ZEFA-Fino’ reached 60 mm in 1.5—2 months after planting out depending on planting date. Plant and bulb weights, bulb width and thickness, stem height inside the bulb and the bulb height in the earliest plantings increased as the growth period lengthened. The bulb width of ‘ZEFA-Fino’ was in higher correlation with bulb weight than bulb thickness or height. The ratio between the height of stem inside the bulb and bulb height increased fastest in the lot planted under cover in May and in the lot planted out in June; at the fourth harvest the relationship was 0.8. The largest number of bolters (8 %) was found in the latter lot. The yield estimate for ‘ZEFA-Fino’ at the third and fourth harvest was 170—360 kg/are depending on planting date and length of the growing season. All lots of ‘ZEFA-Tardo’ except that planted in July bolted quickly after the bulb width had grown to 60—70 mm. The yield quality of ‘ZEFA-Tardo’ was low because of elongated bulbs and great variation in bulb height. Short day treatment (dark period 16 h) of the seedlings retarded but did not inhibit bolting of ‘ZEFA-Tardo’.
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Kamal, Neel, and Christopher S. Cramer. "(248) Does Harvesting Stage Affect Bulb Quality in Spring-sown Onions?" HortScience 41, no. 4 (2006): 1046B—1046. http://dx.doi.org/10.21273/hortsci.41.4.1046b.
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Onions grown in New Mexico are currently harvested manually at 80% tops down (TD). Mechanical harvesting is a matter of urgency for growers in order to remain competitive and to reduce their cost and time. The objective of this study was to find the effect of different harvest stages on bulb quality. Twelve different onion cultivars were sown in Feb. 2004 in Las Cruces, N.M. The experiment was laid out in split-plot design with four harvest treatments based on physiological maturity—20% TD, 80% TD, 1 week after 80% TD, and 2 weeks after 80% TD as whole plots, with cultivars as sub-plots. After curing, data on harvest date, bulb diameter, height, firmness, number of growing points, average center diameter, fleshy scale number, and scale thickness were collected. Maximum number of scales was observed when bulbs were harvested 2 weeks after 80% TD, while average scale thickness was greatest when bulbs were harvested 1 week after 80% TD. Significant treatment by cultivar interaction was observed for bulb firmness. Cultivars Cimarron, Sierra Blanca and NMSU 04-52-2 produced firmer bulbs in all treatments, while NuMex Casper, NuMex Jose Fernandez and NuMex Centric produced firmer bulbs than others, only at 20% TD. Maximum bulb firmness was observed in NMSU 04-28 and NMSU 03-52-1 than others, when harvested 1 or 2 weeks after 80% TD. Overall, bulbs harvested 1 to 2 weeks after 80% TD exhibited firmer bulbs with more scales and greater scale thickness.
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Singh, Jagtar, and Christopher S. Cramer. "(18) Is Withholding Irrigation during Winter Months Detrimental to Onion Bulb Quality?" HortScience 41, no. 4 (2006): 1064D—1064. http://dx.doi.org/10.21273/hortsci.41.4.1064d.
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Onion growers in New Mexico often withhold irrigation for overwintered onion varieties during the months of December and January. This study was initiated to determine if this deficit irrigation program is detrimental to onion bulb quality. Twelve short- and intermediate-day onion cultivars, which differed in their maturity, were seeded in Sept. 2004 in Las Cruces, N.M. Once plants were established, 12 plots of each cultivar were not irrigated during the months of December and January (dry treatment), while the same number of plots was irrigated during these months (wet treatment). Once a plot had 80% of the plants with tops down, all bulbs were harvested, cured, and data on date of harvesting, bulb diameter, bulb height, firmness rating, number of centers, scale number, and scale thickness of first and third fleshy layers were collected. For most of the bulb traits measured, there was no difference between the two irrigation treatments for the cultivars tested. For the earliest-maturing cultivars, bulbs grown in the dry treatment had on average more fleshy scale layers than the bulbs grown in the wet treatment. For later-maturing cultivars, bulbs grown in the dry treatment had more growing points (centers) per bulb than the bulbs grown in the wet treatment. For the latest-maturing cultivars, average fleshy scale layer thickness was greater for bulbs grown in the dry treatment. From this work, a winter deficit irrigation program appears to be detrimental to the percentage of single-center bulbs for later-maturing, autumn-sown onion cultivars.
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Doruchowski, Roch W. "Variability and heritability of some onion (Allium cepa L.) characteristics of parental forms, F1 hybrids and F2 generation." Acta Agrobotanica 39, no. 2 (2013): 293–325. http://dx.doi.org/10.5586/aa.1986.025.
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The object of the studies in 1977 was a population of 15 F<sub>1</sub> hybrids, 11 F<sub>2</sub> progenies and 16 parental forms (8 male-sterile A lines and 8 inbred C lines - Table 2). Variability and heritability of some onion characteristic weight, height diameter of the bulbs and their shape, collar thickness, adherence and color of dry outer skin, bulb firmness, shape of the collar and position of root disc) were studied. Variability and heritability estimates of bulb weight, diameter and shape of the collar were relatively high (30-70%).Variability of the skin thickness was also high, but heritability of this trait was low. The lowest variability and heritability were shown for bulb firmness. The high heritability of some traits indicates the possibility of increasing the effects of selection and improvement, especially of the weight and shape of bulbs.
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Kamal, Neel, and Christopher S. Cramer. "(16) Delayed Harvesting Results in Firmer Fall-sown Onions." HortScience 41, no. 4 (2006): 1064B—1064. http://dx.doi.org/10.21273/hortsci.41.4.1064b.
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Onions grown in New Mexico currently are hand-harvested. In order to remain competitive and to lower production costs, growers will need to harvest onions mechanically. The current recommendation for harvest time is when 80% of onion tops have fallen. The objective of this study was to measure several bulb quality traits when bulbs were harvested at four different stages. Twelve short- and intermediate-day onion cultivars of different maturities were sown during Sept. 2004 in Las Cruces, N.M. Bulbs were harvested at four stages of physiological maturity: 20% tops down (TD), 80% TD, 1 week after 80% TD, and 2 weeks after 80% TD. After curing, data on harvest date, bulb diameter, height, firmness, number of growing points, average center diameter, fleshy scale number, and thickness were collected. For most traits, no differences existed among the different treatments. For the earliest-maturing cultivars, the maximum bulb firmness and number of scales were observed when bulbs were harvested 2 weeks after 80% TD. For later-maturing cultivars, the maximum number of scales was observed 1 week after 80% TD, while the maximum bulb firmness was observed at 2 weeks after 80% TD. For latest-maturing cultivars, bulbs harvested at 1 week after 80% TD were firmer than bulbs harvested at other times. For later-maturing cultivars, average scale thickness was greatest when bulbs were harvested 2 weeks after 80% TD. From this work, a delayed harvest of 1 to 2 weeks after 80% TD resulted in firmer bulbs with more scales.
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Walker, Ryan L., Sunggil Kim, Javier F. Betran, Kilsun Yoo, and Leonard M. Pike. "Investigation of Doubled Haploid Performance and Combining Ability in Short-day Onion." HortScience 41, no. 4 (2006): 990B—990. http://dx.doi.org/10.21273/hortsci.41.4.990b.
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Onions suffer from severe inbreeding depression, which has inhibited the development of homozygous inbred lines in breeding programs. The creation of doubled haploid (DH) lines in onion provides a unique opportunity to evaluate the utility of such lines as parents in a breeding program. For this purpose, two diallele cross experiments were conducted. The first consisted of a six-parent diallele cross using six DH lines developed at Texas A&M University. The second, a four-parent diallele cross performed with two DH lines and two inbred lines from the breeding program. Bulbs from the various crosses were evaluated for diameter, height, centers/bulb, ring thickness, number of rings/bulb, bulb weight, soluble solids content, and pungency. For some traits, general combining ability (GCA) effects explained most of the variation. However, for other traits, specific combining ability (SCA) effects predominated. For all traits, GCA and SCA were always larger than the reciprocal effects (divided into maternal and nonmaternal components). The GCA and SCA effects show an inverse correlation between the number of centers/bulb and ring thickness.
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Tullo, Abe. "Study on Some Engineering Properties of Holeta Local Variety Garlic (Allium Sativum L.) Grown in Ethiopia." American Journal of Food Science and Technology 1, no. 2 (2022): 1–7. http://dx.doi.org/10.54536/ajfst.v1i2.1079.
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Garlic (Allium Sativum L.) is an important root vegetable that can be used as a spice in meals and has historically been used as a remedy for various ailments in Ethiopia. The physical properties of the garlic bulbs and cloves were determined for use in the prototype design. The result showed that the equatorial diameter, polar diameter, thickness, geometric mean diameter, arithmetic mean diameter, sphericity, shape index, surface area, moisture content, hundred garlic bulb weight, bulk density, and angle of repose of the garlic bulbs were 45.89, 42.86, 30.43, 39.08 and 39.71 mm, 0.86, 1.34, 17.08 cm2, 66%, 2530 g, 596.70 kg/m3, and 49.7o for garlic bulbs, respectively. Similarly, the result of the width, length, thickness, geometric mean diameter, arithmetic mean diameter, sphericity, shape index, surface area, hundred garlic cloves weight, bulk density, and angle of repose of the garlic bulbs were 14.44, 31.02, 11.63, 17.15, and 20.07 mm, 0.57, 1.27, 4.06 cm2, 239.4 g, 468.4 kg/m3, and 37.56o for garlic cloves, respectively. Therefore, these physical and mechanical properties of garlic bulbs and cloves were used in designing machine parts.
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Doruchowski, Roch W. "Correlation of some onion (Allium cepa L.) traits." Acta Agrobotanica 39, no. 2 (2013): 347–58. http://dx.doi.org/10.5586/aa.1986.028.
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The research was carried out in 1977 and 1978. Investigations on the correlation of 6 bulb traits showed that bulb weight was determine by bulb diameter in particular. The bulb diameter increased together with the increase in bulb hegiht, collar thickness and diameter of the root disc.
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S R, Singh, Ahamed N, Srivastava K K, Kumar D, and Yousuf S. "Assessment of Genetic Divergence in Long Day Onion (Allium cepa L.) through Principal Component and Single Linkage Cluster Analysis." Journal of Horticultural Sciences 15, no. 1 (2020): 17–26. http://dx.doi.org/10.24154/jhs.2020.v15i01.003.
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To assess the nature and magnitude of genetic diversity in long day onion germplasm by using the principal component analysis and single linkage cluster analysis an experiment was carried out with 34 onion genotypes. High coefficient of variation with wide range in traits indicated an appreciable variability in germplasm. Genotypes were classified into seven principal components having Eigen value > 1, cumulatively accounted for 83.87% of total variability. Principal Component - I contributed for 24.73% of total variation for followed by principal component-II (15.27%). PC-I had high positive loading for bulb weight (0.401), marketable yield (0.338), total bulb yield (0.401) and PC-II had high positive loading for plant height (0.412), PC-III for high T.S.S. (0.276) PC -IV for A grade bulbs (0.436), PC-V for polar diameter of bulbs (0.514), PC-IV negatively loaded with purple blotch (-0.461) and PC-VII for narrow neck thickness (-0 .515). Plotting PC-I aganist PC-II differenciated CITH-O-13, CITH-O-4, CITH-O-22, CITH-O-19, CITH-O-9, CITH-O-6 and CITH-O2 as most divergent genotype.On the basis of single linkage cluster means cluster-I was most importent for average bulb weight, minimum bolters, high marketble bulb percentage high marketable and total bulb yield whereas cluster -II was important for maximum nuber of leaves/plant and minimum neck thicknes. Highest inter-cluster distance was observed between cluter II and Cluster-I(873.5% ).Most divergent genotypes with high inter cluter distance could be the most appropriate parents for crop impovement in onion.
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S R, Singh, Ahamed N, Srivastava K K, Kumar D, and Yousuf S. "Assessment of Genetic Divergence in Long Day Onion (Allium cepa L.) through Principal Component and Single Linkage Cluster Analysis." Journal of Horticultural Sciences 15, no. 1 (2020): 17–26. http://dx.doi.org/10.24154/jhs.v15i1.778.
Full textAbstract:
To assess the nature and magnitude of genetic diversity in long day onion germplasm by using the principal component analysis and single linkage cluster analysis an experiment was carried out with 34 onion genotypes. High coefficient of variation with wide range in traits indicated an appreciable variability in germplasm. Genotypes were classified into seven principal components having Eigen value > 1, cumulatively accounted for 83.87% of total variability. Principal Component - I contributed for 24.73% of total variation for followed by principal component-II (15.27%). PC-I had high positive loading for bulb weight (0.401), marketable yield (0.338), total bulb yield (0.401) and PC-II had high positive loading for plant height (0.412), PC-III for high T.S.S. (0.276) PC -IV for A grade bulbs (0.436), PC-V for polar diameter of bulbs (0.514), PC-IV negatively loaded with purple blotch (-0.461) and PC-VII for narrow neck thickness (-0 .515). Plotting PC-I aganist PC-II differenciated CITH-O-13, CITH-O-4, CITH-O-22, CITH-O-19, CITH-O-9, CITH-O-6 and CITH-O2 as most divergent genotype.On the basis of single linkage cluster means cluster-I was most importent for average bulb weight, minimum bolters, high marketble bulb percentage high marketable and total bulb yield whereas cluster -II was important for maximum nuber of leaves/plant and minimum neck thicknes. Highest inter-cluster distance was observed between cluter II and Cluster-I(873.5% ).Most divergent genotypes with high inter cluter distance could be the most appropriate parents for crop impovement in onion.
Dissertations / Theses on the topic "Bulb thickness"
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Jittavanich, Kotchanun. "Modeling, Simulations, and Parametric Studies of the Dip Coating Process with the Effect of Solvent Evaporation Rate and Bulk Reaction Rate." University of Akron / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=akron1222359806.
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Gopal, Anamika. "Effects of Thickness, Morphology and Molecular Structure of Donor and Acceptor Layers in Thermally Interdiffused Polymer Photovoltaics." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/27279.
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An in-depth study of concentration gradients in thermally-interdiffused polymer – fullerene photovoltaic devices, with a focus on thickness and heat treatments, is presented in this thesis. Device performance is improved from the bilayer by the creation of a concentration gradient of the donor and acceptor materials throughout the active layer of the device. Concentration gradients are expected to improve device performance by optimizing the charge transfer, transport and collection processes. This is achieved through heat-induced interdiffusion of the two materials at temperatures above the glass transition temperature of the polymer. Investigation of the poly(3-octylthiophene) (P3OT) – C₆₀ system show a three-fold improvement in the external quantum efficiencies (EQE) as compared with bilayer devices.
Auger spectroscopy, combined with argon-ion beam milling, serves to record the concentration depth profile and identify concentration gradients in the device through detection of the sulfur in the P3OT backbone. Concentration gradients are optimized to yield the best devices through a thickness variation study conducted on the P3OT – C₆₀ system for fixed thermal interdiffusion conditions at 118 °C for 5 minutes. An optimum thickness of 40 to 60 nm is obtained for the two materials that yields the ideal morphology of a concentration gradient as recorded by Auger spectroscopy. For such devices, the concentration gradient is seen to extend through the device, ending in a thin layer of pure material at each electrode. A monochromatic power conversion efficiency of 2.05% is obtained for 5.3 mW/cm²⁺ illumination at 470 nm.
A brief study is also presented to optimize the concentration gradient profile through variations of the thermal parameters. The dependence of the concentration gradient on the interdiffusion time and temperature is investigated. The merits of heat treatment on the crystallinity of P3OT and the overall device performance are also discussed. It is shown in some case that devices with annealed P3OT layers show almost twice the EQE as non-annealed P3OT layer devices.
Potential alternatives for C₆₀ in interdiffused devices with P3OT have been presented. [6,6]-phenyl C₆₁-butyric acid methyl ester (PCBM), a well-investigated acceptor for blend devices, is studied as an acceptor in concentration gradient devices. A method for spin-coating uniform bilayers of P3OT and PCBM, without solution damage to either layer, is presented. A thermal variation study of the interdiffusion conditions on this system indicated higher interdiffusion temperatures and times are preferred for P3OT – PCBM systems. For interdiffusion at 150 °C for ten minutes, EQE values approaching 35 % at 500 nm are obtained. Auger spectroscopy studies on this system yielded the same conclusions about the concentration gradient device morphology that gives optimum device output. 1:1 and 1:2 blends of P3OT – PCBM are also studied. The influence of various thermal treatments on these devices is described.
The endohedral fullerene Sc₃N@C₈₀ is introduced as a new acceptor material. The endohedral fullerene consists of Sc₃N cluster enclosed in a C₈₀ cage. An order of magnitude increase is seen in device performance upon sublimation of these molecules on a P3OT layer confirming its effectiveness as an acceptor. Preliminary studies done on this system indicated the need for greater thermal treatment to produce optimum concentration gradients. An in depth study for varying temperatures and times is presented. The best device performance was seen for interdiffusion at 160 °C for 25 minutes. The endohedral fullerene devices also show a long-term deterioration and so best result are presented from a set of devices fabricated within the same time period.
The study of these three donor-acceptor systems confirms that the conclusions on the thickness dependence and device performance study conducted for the P3OT – C₆₀ system extend to other acceptors.
A model of EQE for varying thicknesses based on absorption in the interdiffused concentration gradient regions is also presented. This model effectively highlights the influence of P3OT layer thickness on the trends observed in the EQE. It did not, however, reproduce the experimental thickness variation results for varying C₆₀ thicknesses. Incorporation of the effects of the electric field intensity distribution is expected to correct for this. Suggestions have been given on how this might be achieved.<br>Ph. D.
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Thomas, Paul J. S. "Ellipsometry, reflectance and modulated spectroscopy of bulk and multi-layer semiconductor structures." Thesis, University of Surrey, 2000. http://epubs.surrey.ac.uk/844284/.
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Vertical-cavity surface-emitting lasers (VCSELs) are complex multi-layer structures whose operating characteristics are highly sensitive to variations in layer thickness and composition. They contain an active region of one or more quantum wells sandwiched between highly reflecting mirrors. Non-destructive optical characterisation techniques including reflectance spectroscopy, spectroscopic ellipsometry and photomodulated reflectance have been used to examine these structures and various components of them. In addition, the relatively novel technique of photomodulated spectroscopic ellipsometry has been examined in comparison with photomodulated reflectance in the characterisation of bulk, multi-layer and quantum well material. The distributed Bragg reflectors of VCSELs provide the high reflectance required over a selected wavelength range. Optical measurements were used to determine important information concerning layer thicknesses and compositions, which were confirmed with X-ray diffraction and transmission electron microscopy. The techniques were also used to provide important information concerning growth and uniformity, which could be readily applied for feedback to growers or for device fabrication. Novel reflectance and photomodulated reflectance measurements made on a range of laser structures designed to operate over a range of wavelengths from 650 nm to 1 ?m were used to examine the characteristics of the reflectors and the active region of the lasers. The cavity mode observed clearly indicates the lasing wavelength, and the interaction of the cavity and quantum well has been interpreted using new lineshapes. The cavity mode and quantum well resonance observed in photomodulated reflectance has been shown to provide a clear indication of where devices can be fabricated successfully from non-uniform material. The identification of the cavity and quantum well features has also enabled important information concerning the changes in structure and therefore in device performance with temperature and pressure. Measurements have also been able to provide important information to explain the variation in performance of some devices.
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Belkadi, Nesrine. "Nouveaux MEMS C-BAR : résonateurs capacitifs à ondes élastiques de volume piégées sur substrat Silicium." Thesis, Besançon, 2016. http://www.theses.fr/2016BESA2088.
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Ces travaux de thèse décrivent l’étude et la réalisation de résonateurs MEMS (Micro-ElectroMechanical Systems) acoustiques à couplage capacitif dits C-BAR (Capacitive Bulk Acoustic Resonator). Les C-BAR exploitent les modes d’extension-compression d’épaisseur en mode fondamental à 9, 45MHz. L’élément vibrant est constitué de Si-monocristallin purement résistif et d’orientation (100). Notre but consiste à transposer au monde des MEMS a` excitation capacitive les caractéristiques de stabilité des résonateurs piézoélectriques BAW utilisés dans les sources de fréquences embarquées. Notre stratégie de développement s’est fondée sur l’exploitation de deux concepts originaux dans les domaines respectifs électrique et acoustique : l’intérêt immédiat des résonateurs MEMS-Si capacitifs tient à la disponibilité du matériau, au faible coût unitaire, à la produire à grande échelle, ainsi qu’à la robustesse. A plus longue échéance, cet intérêt tient au potentiel d’intégration avec l’électronique de commande ; Cette recherche est motivée par la nécessité d’éliminer les pertes structurelles dans les résonateurs MEMS. Grâce à l’étude de la dispersion acoustique des ondes élastiques guidées dans une plaque de Si, nous avons pu contrôler les bandes d’arrêt par modification locale des caractéristiques de la propagation afin de confiner l’énergie acoustique au centre du résonateur. Une première partie de ces travaux est consacrée à la modélisation du C-BAR. Grâce à des simulations FEM appuyées sur des calculs analytiques, nous avons défini les limites imposées aux paramètres constructifs pour l’obtention de performances satisfaisantes pour les applications visées. Nous avons notamment quantifié le nécessaire compromis entre les quantités antagonistes constituées par le k2, limité par la rigidité statique de la plaque, et le Q, limité par les constantes de dispersion des modes exploités et le facteur d’aspect de la plaque. La deuxième partie est consacrée à la micro-fabrication du C-BAR exploitant les micro techniques disponibles au sein de la Centrale MIMENTO<br>This PhD work describes the study and realization of capacitive Bulk Acoustic Waves MEMS resonators (C-BAR) exploiting the thicknessextensional vibration modes at 9, 45MHz of a mono-crystalline silicon plate (100). The aim of this research consists in translated to the domain of capacitive MEMS the good performances of BAW resonators for embedded frequency sources. The proposed work proposes new resonant structures bearing some originality from electric and acoustic viewpoints : capacitive full Si-MEMS have some immediate interest in the field of material availability, low cost per item, volume production and robustness, notwithstanding their know ability for electronic integration ; This research was motivated by the need to eliminate structural losses to reach the limits imposed by the material itself. With help of a study of dispersion curves, we managed a control of acoustic confinement by means of a local patterning of the surface of the vibrating element. By a proper mastering of the stop band of guided elastic waves in the structure, we can overcome the intrinsic limitations of structural MEMS. The first lock of this work is dedicated to the modeling of the C-BARs. It uses a combination of analytic and FEA calculations to frame the actual design of the resonators. This permits us to determine the limits imposed to the performances of such structures. This part especially points out the contradictory requirements of the C-BARs in terms of electromechanical coupling factor and of surtension coefficient. The second lock describes the issues of the micro-fabrication of the C-BARs at MIMENTO clean room facility
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Poupon-Pourchot, Daphnée. "Plasticité cérébrale dans le système olfactif : étude du modèle des sommeliers." Thesis, 2020. http://hdl.handle.net/1866/25550.
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Cette thèse s’intéresse à la capacité du cerveau à s’adapter à un environnement changeant. Plus spécifiquement, elle s’intéresse à la plasticité cérébrale dans le système olfactif. Les sommeliers, experts dans le domaine de l’olfaction, ont constitué notre modèle.
Une première étude nous a permis d’établir un protocole afin de tester la performance olfactive des sommeliers.
Dans une deuxième étude, nous avons testé des étudiants en sommellerie au début de leur formation d’un an et demi qui mène à la profession de sommelier. Nous avons observé que ces futurs experts de l’olfaction présentaient déjà, au cours des deux premiers mois, des capacités olfactives supérieures.
Dans une troisième étude, nous avons de nouveau testé les étudiants à la fin de leur formation, afin d’examiner les effets d’un entraînement olfactif à long terme sur la performance olfactive et sur le cerveau : en plus de mesurer les capacités olfactives avec le test des Sniffin’ Sticks, nous avons utilisé l’imagerie par résonance magnétique (IRM) pour évaluer l’évolution du cerveau au cours de la formation en sommellerie. Nos principales observations concernent des changements au niveau de la structure cérébrale. Premièrement, le volume du bulbe olfactif a augmenté au cours de la formation, ce qui est en accord avec la littérature disponible à propos de cette structure. Deuxièmement, nous avons observé un épaississement au niveau du cortex entorhinal mais aussi un amincissement au niveau d’autres régions du cortex. Mises en relation avec les résultats d’études antérieures, ces observations soutiennent le récent modèle de surproduction-élagage selon lequel les changements dus à la plasticité liée à l’entraînement ne sont pas linéaires mais font intervenir différents processus en plusieurs phases. Ce modèle constitue une avancée importante dans la compréhension des mécanismes impliqués dans la plasticité cérébrale et devrait être pris en compte dans les futures études sur la plasticité.
Bien que les résultats sur le plan neuroimagerie soient intéressants, les résultats de l’étude longitudinale relatifs à la performance olfactive n’étaient pas concluants sur le plan comportemental. Nous avons donc mis en place dans une quatrième étude une tâche d’identification d’odorants au sein de mélanges plus complexe et plus adaptée aux sommeliers qui a confirmé la supériorité de leurs capacités olfactives. Nous avons aussi entraîné des novices sur cette tâche pendant cinq jours pour tester les effets d’un court entraînement olfactif.
Cette thèse est organisée sous forme de thèse par articles. Le premier chapitre correspond à l’introduction générale, qui est elle-même organisée en plusieurs grandes parties. Ces différentes parties définissent les concepts-clés de cette thèse : l’olfaction, les corrélations neuroanatomiques dans le système olfactif, la plasticité cérébrale, la plasticité liée à l’entraînement dans le système olfactif, la neuroimagerie. La dernière partie conclut l’introduction en présentant les objectifs et hypothèses de recherche. Les chapitres suivants correspondent aux articles rédigés au cours du doctorat et présentant les résultats des recherches. Le dernier chapitre constitue une discussion générale. Enfin, en annexes se trouvent deux articles publiés lors du doctorat, un chapitre à paraître dans un livre ainsi que des résultats non publiés.<br>This thesis is about the brain’s ability to adapt to an ever-changing environment. More specifically, it is about brain plasticity in the olfactory system. We used sommeliers, who are experts in olfaction, as our model.
A first study allowed us to instate a protocol to assess sommeliers’ olfactory function.
In a second study, we tested sommelier students at the start of their year-and-a-half-long training which is the prerequisite to become a professional sommelier. We observed that these future experts in olfaction already had, during the first two months of training, superior olfactory abilities.
In a third study, we tested sommelier students again at the end of their training to examine the effects of a long-term olfactory training on olfactory performance and on the brain: beside assessing olfactory performance with the Sniffin’ Sticks test, we used magnetic resonance imaging (MRI) to examine the evolution of brain structure and function during sommelier training. Changes in brain structure constituted our main results. Firstly, olfactory bulb volume increased during sommelier training, which is in line with previous reports about this structure. Secondly, we observed a cortical thickness increase in the entorhinal cortex but also cortical thinning in other brain areas. Put together with findings from previous studies, these results support the recent overproduction-pruning model of plasticity according to which changes due to training-related brain plasticity are nonlinear but involve different processes and different phases. This model constitutes a great advance in the understanding of brain plasticity and its underlying mechanisms and should be considered in future studies about plasticity.
Though neuroimaging results were interesting, results from olfactory tests in our longitudinal study were not conclusive so we conducted a fourth study to test the ability to identify odorants within mixtures, a task which is more complex and suitable for sommeliers than the Sniffin’ Sticks test. Sommeliers performed better. We also tested novices that we had trained on this task for five days to evaluate the effects of a short-term olfactory training.
This thesis is organized by articles. The first chapter is a general introduction, itself organized in several parts. These different parts define the major concepts of this thesis: olfaction, neuroanatomical correlations in the olfactory system, brain plasticity, plasticity in the olfactory system, neuroimaging. The last part concludes the introduction with aims and hypotheses. The following chapters are articles written during PhD that present the results of our research. The last chapter is a general discussion of all the results. Finally, two articles published during PhD, a chapter that is to be published in a book and unpublished results are presented as appendices.
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YE, CHAN-HONG, and 葉展宏. "Study on Thickness Distribution and Spring Back Phenomena of Sheet-Bulk Forming for Aluminum Alloy." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/70220663549864595342.
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碩士<br>國立高雄應用科技大學<br>機械工程系<br>105<br>With the improvement of process technology, Aluminum alloy is widely used in many industries. The function of aluminum alloy product gradually change to functional integration of product from a single function. It is important to study the formability and spring back phenomena of thick aluminum alloy sheet.
In this study, we used Deform 3D and Simufact.forming to simulate the sheet-bulk forming for thick aluminum alloy sheet. Mesh convergence analysis was conducted to find the optimal element size. Thickness distribution and spring back phenomena of the rectangular blank with round corners feature at process one was also investigated. Simulation results were compared to scanning file based on spring back phenomena.
The results are as follows: the optimal element size is 2 mm in the mesh convergence analysis. Compared to tetrahedral elements, solid-shell elements are suitable for analyzing sheet bulk metal forming process. Cross section near binder area of the x-axis and near quarter of keyboard of the y-axis area it has minimum spring back phenomena.
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Xu, Rui-Fu, and 許瑞福. "Broadband Polarization Control of Bulk Acoustic Wave-Mediated Multiferroic Antenna Based on Thickness Shear Modes." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9kpxm5.
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碩士<br>國立臺灣大學<br>電信工程學研究所<br>107<br>Antenna miniaturization has been more and more important these days. Many applications like IOT, biomedical devices, wearable devices, and 5G demand higher performance with smaller feature size. Many works on antenna miniaturization have been done before, such as using substrate with high permittivity or permeability, diverse structure antenna design, etc. However, no matter in UHF or VLF band, as long as the electrical size of an antenna is much smaller than one, the radiation efficiency will be extremely low, making the antenna infeasible. In 2015, theoretical groundwork of using multiferroic material to achieve antenna miniaturization was firstly propose, named “bulk acoustic wave-mediated multiferroic antenna”. The core concept is that the wavelength of mechanical wave is five orders of magnitude smaller than electromagnetic wave under the same resonant frequency. As long as the loss can be further reduced, it owns great potential to approach Chu’s limit for electrically small antennas.
In the above mentioned works, the radiation is mainly generated based on longitudinal acoustic wave. In this thesis, thickness shear mode is used instead of longitudinal one. By using the shear mode, two sets of symmetrical but orthogonal resonant modes can be manipulate by applying 90° phase difference to generate circularly polarized (CP) wave. In addition, the shear wave can excite in-plane magnetic current, which will double the radiation instead of cancelling out each other when the device is placed above a metallic ground plane according to the image theory. Such concept can also be used for tunable polarization control. The design concept is preliminarily investigated through FEM-based multi-physics solver, COMSOL, and post processing by an in-house MATLAB code. It is shown that under the ideal input RF signal pair of equal magnitude and with 90° phase difference, the proposed design can achieve very broadband CP with satisfactorily low in-band axial ratio. The design is fabricated by Dr. Sidhant Tiwari from UCLA. The test pieces were tested, and the results thus obtained are presented and discussed through a couple of comparisons. This work envisions the possibility of broadband polarization control and/or tunability of electrically small antennas.
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Chen, Jiun Hung, and 陳俊宏. "A study of different thickness ratio of Ni、Ge、Si recording film for the write-once bule-ray disk." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/56541514022796813556.
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碩士<br>中興大學<br>材料工程學系所<br>95<br>Recently﹐the recording of blue-ray write-once disk are mainly made by a-Si/Cu . However﹐due to the advances of the blue-ray disk technique day by day﹐the multi-layers is developed successfully . Therefore﹐we need to further increase the data transfer rate﹐but must change the film structure or use the other material to instead of a-Si .
In this study﹐different thickness ratio of a-Ge/Ni、a-Si/a-Ge/Ni and
a-Ge/Ni/a-Si recording film by an ion beam assisted deposition(IBAD) system was adopted as the recording layer for the blue-ray write-once disk . Learnt by the experimental result﹐a-Ge(20 nm)/ Ni(1 nm) of recording film only the phase variety of two stages happen, the first stage will have obvious reflectivity increment between 400~440 ℃, the second stage is in the anneal temperature after raising to 500 ℃. Take place the droop of reflectivity. Between 400~440 ℃ reflectivity varieties change for the amorphous Ge crystallization, the reflectivity after 540 ℃ droop for crystallize melting of Ge. Ge(20 nm)/Ni(2 nm) record film has the reflectivity of four stages and changes in the anneal process. The first stage is forming Ni5 Ge3 phase by Ni and Ge inter-diffusion . The variety of second stage is the Ni5 Ge3 and Ge wedge bonding to become NiGe phase. The third stage goes to 390 ℃ for the anneal or so then will have the crystallize germanium . The Ge of the fourth stage occurrence melts to cause of reflectivity droop. And a-Si/a-Ge/Ni at the phase change generated by the anneal temperature of below 500 ℃ all and a-Ge(20 nm)/Ni(2 nm) record film homology, and can generate in above 500 ℃ the second-time reflectivity increment .Suggest being because forming Ni-Si compound cause. So we infer it when can apply blue-ray write-once disk , can because of reflectivity again increase of the phenomemon raise between as-deposition and data write of reflectivity difference.
For the a-Ge/Ni/a-Si record film, after 580 ℃ anneal transactions, become the gradient of the reflectivity rising of crystallize Ge reduces after 580 ℃ anneal transactions and occurrence reflectivity again increase of the phenomemon of gradient droop. On the other hand in element depth composition analysis, we find Ni and Ge will produced inter-diffusion but a-Si and a-Ge will be not easy. Also find that the Ni atom will spread into a Si substrate after anneal.
In activation energy analysis, the add of amorphous Si layer that can reduce amorphous Ge to change crystallize Ge phase change activation energy but will raise phase variety temperature. The affix of besides amorphous Si layer can also reduce the phase of the Ni5Ge3 phases change activation energy, while the Ni5Ge3 change the activation energy smaller record film forming NiGe phase of the phase change the activation energy is also lower. The residual stress analyzes, understand all as-deposited of record membranes in order to compress stress.If there are more remain stress in the recording films, the heat which is needed to " relaxation " the stress is higher. So that delays the phase change temperature which produce Ni5Ge3.
Books on the topic "Bulb thickness"
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United States. National Aeronautics and Space Administration., ed. System for the growth of bulk SiC crystals by modified CVD techniques: Final report. National Aeronautics and Space Administration, 1994.
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Influence of bulk turbulence and entrance boundary layer thickness on the curved duct flow field. National Aeronautics and Space Administration, Scientific and Technical Information Division, 1988.
Find full textBook chapters on the topic "Bulb thickness"
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Hirose, Y., N. Takano, Y. Nanayama, and T. Mura. "The Thickness Measurements of Thin Bulk Film By X-Ray Method." In Advances in X-Ray Analysis. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3744-1_61.
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Vo, D. T. "The Measurement of Uranium Enrichment." In Nondestructive Assay of Nuclear Materials for Safeguards and Security. Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-58277-6_8.
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AbstractUranium enrichment can vary dramatically depending on the application. In the nuclear fuel cycle uranium is typically low enriched but for military applications it is often high enriched while depleted uranium is commonly used for commercial applications. Measurement of the uranium enrichment can assist in verifying that the uranium is being used in the application as declared. This chapter covers the definition of uranium enrichment, various techniques for assaying the enrichment, and correction factors for wall attenuation. The enrichment measurement principles presented include the infinite-thickness for bulk uranium, the peak ratio using HPGe, visual estimation from a spectrum, and gas-phase enrichment for UF6 techniques.
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Jiménez, Yolanda, Marcelo Otero, and Antonio Arnau. "Data analysis and Interpretation in Bulk Acoustic Wave — Thickness Shear Mode Sensors." In Piezoelectric Transducers and Applications. Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-662-05361-4_16.
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Bensenouci, S., B. Bachiri, and K. Rahmoun. "Effect of Thickness and Temperature on Bulk Heterojunction Organic Solar Cells Performance." In Springer Proceedings in Energy. Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-99-2777-7_57.
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Tsuji, Nobuhiro, Shigenobu Ogata, Haruyuki Inui, Isao Tanaka, and Kyosuke Kishida. "Proposing the Concept of Plaston and Strategy to Manage Both High Strength and Large Ductility in Advanced Structural Materials, on the Basis of Unique Mechanical Properties of Bulk Nanostructured Metals." In The Plaston Concept. Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-7715-1_1.
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AbstractAdvanced structural materials are required to show both high strength and large ductility/toughness, but we have not yet acquired the guiding principle for that. The bulk nanostructured metals are polycrystalline metallic materials having bulky dimensions and average grain sizes smaller than 1 μm. Bulk nanostructured metals show very high strength compared with that of the coarse-grained counterparts, but usually exhibit limited tensile ductility, especially small uniform elongation below a few %, due to the early plastic instability. On the other hand, we have recently found that particular bulk nanostructured metals can manage high strength and large tensile ductility. In such bulk nanostructured metals, unusual deformation modes different from normal dislocation slips were unexpectedly activated. Unusual <c+a> dislocations, deformation twins with nano-scale thickness, and deformation-induced martensite nucleated from grain boundaries in the bulk nanostructured Mg alloy, high-Mn austenitic steel, and Ni-C metastable austenitic steel, respectively. Those unexpected deformation modes enhanced strain hardening of the materials, leading to high strength and large tensile ductility. It was considered that the nucleation of such unusual deformation modes was attributed to the scarcity of dislocations and dislocation sources in each recrystallized ultrafine grain, which also induced discontinuous yielding with clear yield drop universally recognized in bulk nanostructured metals having recrystallized structures. For discussing the nucleation of different deformation modes in atomistic scales, the new concept of plaston which considered local excitation of atoms under singular dynamic fields was proposed. Based on the findings in bulk nanostructured metals and the concept of plaston, we proposed a strategy for overcoming the strength-ductility trade-off in structural metallic materials. Sequential nucleation of different deformation modes would regenerate the strain-hardening ability of the material, leading to high strength and large tensile ductility. The strategy could be a guiding principle for realizing advanced structural materials that manage both high strength and large tensile ductility.
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Koul, Sakshi, and Najeeb-ud-Din Hakim. "Investigation of Active Layer Thickness Variation on the Performance of Bulk Heterojunction Organic Solar Cells." In Springer Proceedings in Physics. Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-97604-4_51.
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Khalil, Abdelgalil, Faeez Masurkar, and A. Abdul-Ameer. "Estimating the Reliability of the Inspection System Employed for Detecting Defects in Rail Track Using Ultrasonic Guided Waves." In BUiD Doctoral Research Conference 2023. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-56121-4_19.
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AbstractThis work focuses on the implementation of a data-based method to determine the inspection system reliability in terms of detecting different types of damages in rail tracks using ultrasonic-guided Rayleigh waves and a probability of detection (POD) technique. In this study, the reliability is tested against a surface crack (SC) and sub-surface damage – a through-side thickness hole (TSTH). The guided Rayleigh waves are generated using a custom-designed sensor that excites Rayleigh surface waves in the specimen and the propagating waves are sensed on the rail track surface. The wedge shape design of the sensor helps to excite a specific ultrasonic mode in the sample thereby hindering the ultrasonic energy of other coupled guided waves that can propagate simultaneously and the wedge angle is determined according to Snell’s law relying on the wave velocity of Rayleigh wave and bulk longitudinal wave. The guided wave responses as a function of varying severity of defects are obtained through a simulation study after the verification of the obtained guided wave responses with the help of an experimental study. A damage index (DI) is defined depending on defect size that gives the trend of damage severity from the captured ultrasonic responses and for monitoring defects in the rail track. This DI is eventually fed into the POD model to determine the probability of defect detection which in turn helps determine the inspection system reliability. The POD method also helps to study the critical design parameters that could affect or improve crack detection results.Purpose – To determine the reliability of inspection system deployed for interrogating health status of rail track.Methodology – Employing the Probability of detection technique for determining how reliable the inspection system is in detecting the health status of the rail track specimen using the ultrasonic guided waves.Findings – It has been found that the proposed inspection system is >90% reliable in detecting defects.Implications – This methodology can help maintenance engineers to make an informed decision on their developed technique for investigating the health status of the rail track sample.Originality/ value – 13%.
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Shibasaki, Hiroshi, and Mark Hallett. "Pupils and accommodation." In The Neurologic Examination. Oxford University Press, 2022. http://dx.doi.org/10.1093/med/9780197556306.003.0008.
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There are two kinds of muscles in the eyes: extraocular muscles, which move the ocular bulb, and intraocular muscles, which are innervated by the autonomic nervous system. The intraocular muscles have two functions; one controls the diameter of pupils and the other controls thickness of the lens (accommodation). For examining the ocular muscles, we can start from either muscle, but it is practical to examine the intraocular muscles first in order to avoid overlooking them by examining the extraocular muscles first. First, the shape and diameter of pupils should be observed, paying special attention to possible asymmetry between the two eyes. Asymmetry of pupillary diameter is called anisocoria. A pathologically large pupil is called mydriasis, and a pathologically small pupil is called miosis.
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Balkanski, M., and R. F. Wallis. "Optical properties of heterostructures." In Semiconductor Physics and Applications. Oxford University PressOxford, 2000. http://dx.doi.org/10.1093/oso/9780198517412.003.0017.
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Abstract For bulk semiconductors the determination of the optical absorption coefficient is relatively simple: one measures the attenuation of a light beam passing through a sample of suitable thickness. In the case of quasi-two-dimensional structures the measurement is complicated by the high anisotropy of these systems and their very small thicknesses.
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Mohd Amir, Syed, and Pramod Kumar. "Neutron Diffraction and Reflectometry: A Review on Unique Role in Functional Magnetic Materials." In Nanotechnology and Nanomaterials. IntechOpen, 2024. http://dx.doi.org/10.5772/intechopen.1003634.
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Magnetic materials either in bulk or thin films are ubiquitous in our daily life. Technology based on magnetic materials range from chunk of bulk ferromagnet to thin film spintronics. In solid state bulk materials, information about its magnetic structure together with crystal structure is absolutely necessary to manipulate them in applications. Neutron diffraction is an important tool to determine atomic magnetic moments and its directions at the lattice site in the magnetic unit cell. It also investigates the type of magnetic ordering in conventional as well as new exotic materials. Magnetic thin films are engineered materials in which nanometer or sub-nanometer thickness scale films are grown. At such thicknesses nanoscale magnetic properties are fundamentally different than its bulk counterpart. Neutron reflectometry is a unique tool to investigate nano-magnetism in thin films. Moreover, in multilayer thin films generally used for spintronics, polarized neutron reflectometry is indispensable characterizing tool which investigates the magnetic properties in different layers and at the interfaces. In this chapter, we will introduce how neutron diffraction and reflectometry techniques play unique role in the investigation of magnetic structure and magnetic properties of functional bulk and nano-scale thin films.
Conference papers on the topic "Bulb thickness"
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LaBerge, Kelsen, Joel Johnston, Robert Handschuh, and Gary Roberts. "Evaluation of a Variable Thickness Hybrid Composite Bull Gear." In Vertical Flight Society 74th Annual Forum & Technology Display. The Vertical Flight Society, 2018. http://dx.doi.org/10.4050/f-0074-2018-12859.
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For several years, NASA Glenn Research Center and the U.S. Army Research Laboratory have been investigating hybrid (composite/steel) gear technology for use in vertical lift drive systems. The hybrid gear concept replaces the structural portion of a gear between the shaft and the gear rim with a lightweight carbon fiber composite, in an effort to reduce the overall weight of a gear and increase the drive system power density. Past research includes both small-scale and large-scale hybrid gear concepts, all of which have a constant composite thickness throughout. The design described in this paper is of a variable thickness, such that the composite is thickest at the inner diameter and this thickness is gradually reduced toward the outer diameter. The resulting "stair stepped" design stems from dropping plies of the braided carbon fiber prepreg composite fabric gradually with increased radius. Additionally, the interlock pattern at the inner metallic adapter was adjusted slightly from previous designs to obtain a better stress distribution on the inner metallic adapter. The manufactured variable thickness web was tested both in static torsion tests and operationally in a relevant gearbox environment. The results of these experiments will be presented and compared to a baseline steel configuration.
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Tian, Yuwei, Mengxiao He, Yuanhang Wang, Zhixing Gao, Linyuan Cao, and Yun He. "Comparison of laser-induced plasma spectroscopy of metal zinc in bulk water with different depths/thicknesses." In Sixth International Symposium on Laser Interaction with Matter (LIMIS 2022), edited by Jin Guo, Pengling Yang, Yihua Hu, and Cangtao Zhou. SPIE, 2025. https://doi.org/10.1117/12.3058457.
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Jones, Michael, Gregory de Boer, Richard Woollam, Joshua Owen, and Richard Barker. "Numerical Exploration of a Comprehensive Mechanistic CO2 Corrosion Model Part II: Influence of Hydrodynamics and Bulk pH." In CONFERENCE 2023. AMPP, 2023. https://doi.org/10.5006/c2023-19305.
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Abstract In part two of this two-part series, we further explore the comprehensive mechanistic CO2 corrosion model developed in part one by examining how the changing hydrodynamics influence the system at various bulk pHs. Parametric studies are conducted over the model over an extensive range of fluid velocities, pipe diameters, and bulk pH values. Contour plots are produced showing the variation in key outputs, including the boundary layer properties, corrosion rate, surface pH, and surface saturation ratio with respect to iron carbonate (FeCO3). Changes to the behavior of the system were found to be strongly correlated with the thickness of the boundary layer, determined by the Reynolds number in the bulk flow and the diameter of the pipe. Thinning of the boundary layer was found to result in greater rates of species transport through the boundary layer, accelerating the mass-transport limited surface reactions and reducing the deviation between the bulk and surface concentrations. Hydrodynamic influences were found to be consistent across varying bulk pH conditions, indicating a separation of the effect of flow conditions from the fluid chemistry. The observed trends are discussed in detail in relation to the real-world behavior of fluid flow to improve the understanding of the connection between hydrodynamics and the corrosion process.
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Wright, Ruishu F., Paul R. Ohodnicki, and Margaret Ziomek-Moroz. "Fe Thin Film Coated Optics for Monitoring Internal Corrosion in Natural Gas Pipelines." In CORROSION 2018. NACE International, 2018. https://doi.org/10.5006/c2018-10893.
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Abstract Internal corrosion can occur in the natural gas transmission pipelines when aqueous electrolytes are present. The presence of water results from the condensation of wet gas or liquid water from upstream plant upsets. Dissolved contaminants such as salts, CO2, and H2S make the electrolyte more corrosive. The ability to monitor internal corrosion in natural gas transmission pipelines before it occurs could have a significant impact on preventing methane leaks as well as catastrophic events resulting from corrosion. A recent concept for early corrosion on-set detection involves the use of proxy materials integrated with the optical fiber sensor platform that corrode at a rate which provides insight into the conditions for which pipeline corrosion is expected to occur. Successful realization of this class of sensors requires a detailed understanding of the corrosion behavior of relevant thin film systems. In support of this goal, Fe thin film of different thicknesses (25, 50, 100 nm) on quartz substrates were tested in CO2 saturated 3.5%wt. NaCl solutions at 30 °C. The effects of CO2 and thickness on the corrosion of Fe thin films were studied using optical transmission technique and in situ electrochemical method. The increase in light transmission corresponded to the corrosion of Fe thin films. CO2 accelerated the corrosion of Fe thin films due to the lower pH and promoted corrosion reactions, resulting in a faster increase of light transmission over time than without CO2. While the corrosion rate (CR) increased with the film thickness, the CR of Fe thin films were of the same order of magnitude with the API 5L X65 bulk pipeline material, verifying that Fe thin films can serve as a corrosion proxy when integrated with the optical fiber based sensing platform.
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Putra, Alfian Pramudita, Erik Jan Westerman, and Akif Rahmatillah. "Simulation and computational analysis of fire sprinkle bulb activation with variation of liquid and wall thickness." In THE 2ND INTERNATIONAL CONFERENCE ON PHYSICAL INSTRUMENTATION AND ADVANCED MATERIALS 2019. AIP Publishing, 2020. http://dx.doi.org/10.1063/5.0034043.
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Sauer, H., R. Müller, and K. Vogeler. "Reduction of Secondary Flow Losses in Turbine Cascades by Leading Edge Modifications at the Endwall." In ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0473.
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Experimental results are presented which show the influence on the secondary flow and its losses by a profile modification of the leading edge very close to the endwall. The investigation was carried out with a well-known turbine profile that originally was developed for highly loaded low pressure turbines. The tests were done in a low speed cascade wind tunnel. The geometrical modification was achieved by a local thickness increase; a leading edge endwall bulb. It was expected that this would intensify the suction side branch of the horse-shoe (hs-) vortex with a desirable weakening effect on the passage vortex. The investigated configuration shows a reduction of secondary losses by 2.1% points that represents approximately 50% of these losses compared to the reference profile. Detailed measurements of the total pressure field behind the cascade are presented for both the reference and the modified profile. The influence of the modified hs-vortex on the overall passage vortex can be clearly seen. The results of a numerical analysis are compared with the experimental findings. A numerical analysis shows that the important details of the experimental findings can be reproduced. Quantitative values are locally different. The theoretical approach taken cannot yet be used for an exact prediction of the loss reduction. However the analysis of the interaction and the resulting tendencies are considered to be valid. Hence theoretical investigations as a guideline for the design of a leading edge bulb at the endwall are a valuable tool.
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Jho, Young-Dahl, and Dai-sik Kim. "Real-virtual transition in bulk GaAs: the thickness dependence." In Symposium on Integrated Optoelectronics, edited by Kong-Thon F. Tsen and Jin-Joo Song. SPIE, 2000. http://dx.doi.org/10.1117/12.381465.
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Ragnarsson, L. A., H. Dekkers, P. Matagne, et al. "Zero-thickness multi work function solutions for N7 bulk FinFETs." In 2016 IEEE Symposium on VLSI Technology. IEEE, 2016. http://dx.doi.org/10.1109/vlsit.2016.7573393.
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Bhole, Kiran, Sunil Ekshinge, and Prasanna Gandhi. "Fabrication of Continuously Varying Thickness Micro-Cantilever Using Bulk Lithography Process." In ASME 2014 International Manufacturing Science and Engineering Conference collocated with the JSME 2014 International Conference on Materials and Processing and the 42nd North American Manufacturing Research Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/msec2014-4041.
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This paper presents fabrication of varying thickness polymer micro-cantilever using recently developed and characterized, single scan, three-dimensional (3D) micro-fabrication process termed as “bulk lithography”. The process allows fabrication of 3D microstructures that demonstrate continuous variation in the thickness direction as against the discrete variation provided by the normal microstereolithography (layer-by-layer) and other VLSI processes. The required depth variation is obtained during fabrication by allowing unconstrained depth photopolymerization and varying laser exposure while scanning. Towards goal to achieve the control over cured depth and smooth free surface (down facing surface), the process is characterized for cured depth and width under wide range of energy dose at different exposure duration. The depth characterization, represented earlier in a form of an empirical model, is used programmatically to impose any desired spatial intensity variation during scan. Additional width characterization, presented in this paper, is used to optimize the line spacing for achieving smooth unconstrained surface. Specific case of fabrication of tapered micro-cantilever is demonstrated with the proposed technique.
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Chan, W. J., Y. S. Ang, and L. K. Ang. "Field Emission Model with Diminishing Thickness from Bulk to 2D materials." In 2022 IEEE International Conference on Plasma Science (ICOPS). IEEE, 2022. http://dx.doi.org/10.1109/icops45751.2022.9813353.
Full textReports on the topic "Bulb thickness"
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Kovacs, Austin. Sea Ice. Part 1. Bulk Salinity Versus Ice Floe Thickness,. Defense Technical Information Center, 1996. http://dx.doi.org/10.21236/ada312027.
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