NASA Astrophysics Data System (ADS)
Harvey, Michel; Galbraith, Peter S.; Descroix, Aurélie
2009-01-01
Vertical distribution of various species and stages of macrozooplankton (euphausiacea, chaetognatha, cnidaria, mysidacea, amphipoda) were determined for different times of the day and related to the physical environment. Stratified sampling with the BIONESS was carried out during seven cruises in spring and fall 1998, 2000, and 2001, and fall 1999, in two different habitats in the St. Lawrence marine system: the lower St. Lawrence Estuary and the NW Gulf of St. Lawrence. Our results indicate that the various macrozooplankton species were distributed throughout the whole water column including the surface layer, the cold intermediate layer (CIL), and the deep layer at different times of day and night in both areas during all periods. Moreover, three types of migrational patterns were observed within this zooplanktonic community: (1) nocturnal ascent by the whole population, (2) segregation into two groups; one which performed nocturnal accent and another which remained in the deep, and (3) no detectable migration. We also observed that the diel vertical migration (DVM) amplitude in most of the macrozooplankton species varied as a function of physical factors, in particular the spatio-temporal variations of the CIL thermal properties, including the upper and the lower limits of the CIL and the depth of the CIL core temperature. Finally, the different DVM patterns coupled with estuarine circulation patterns and bottom topography could place animals in different flow regimes by night and by day and contribute to their retention (aggregation) and/or dispersion in different areas, time of the day, and seasons.
Inter-annual variability of exchange processes at the outer Black Sea shelf
NASA Astrophysics Data System (ADS)
Shapiro, Georgy; Wobus, Fred; Yuan, Dongliang; Wang, Zheng
2014-05-01
The advection of cold water below the surface mixed layer has a significant role in shaping the properties of the Cold Intermediate Layer (CIL) in the Black Sea, and thus the horizontal redistribution of nutrients. The minimal temperature of the CIL in the southwest deep region of the sea in summer was shown to be lower than the winter surface temperature at the same location, indicating the horizontal advective nature of CIL formation in the area (Kolesnikov, 1953). In addition to advection in the deep area of the sea, the transport of cold waters from the northwest Black Sea shelf across the shelf break in winter was shown to contribute to the formation of the CIL (Filippov, 1968; Staneva and Stanev, 1997). However less is known of the exchanges between the CIL waters and the outer shelf areas in summer, when a surface mixed layer and the underlying seasonal thermocline are formed. Ivanov et al. (1997) suggested that the cross frontal exchange within the CIL is strongly inhibited, so that CIL waters formed in the deep sea (i.e. offshore of the Rim Current) do not replenish the CIL waters onshore of the Rim Current (also known as near-bottom shelf waters, or BSW), due to strong cross frontal gradients in potential vorticity (PV). To the contrary, Shapiro et al. (2011) analysed in-situ observations over the period of 1950-2001 and showed a high correlation between the CIL temperatures in the open sea and outer shelf. However, the statistical methods alone were not able to clearly establish the relation between the cause and the consequences. In this study we use a 3D numerical model of the Black Sea (NEMO-SHELF-BLS) to quantify the exchange of CIL waters between the open sea and the outer northwest Black Sea shelf and to assess its significance for the replenishment of BSW on the outer shelf. The model has a resolution of 1/16º latitude × 1/12º longitude and 33 levels in the vertical. In order to represent near-bottom processes better, the model uses a hybrid vertical discretisation (s-on-top-of-z) and other improved parameters of the model set-up as in Shapiro et al. (2013). The model was run for the period from 1979 to 2012 with water discharges from 8 main rivers, exchanges through Bosporus and meteo forcing from the Drakkar Forcing Set 5.2 (Brodeau et al, 2010). The model was spun-up from climatological temperature and salinity in January using a semi-diagnostic adjustment method. Each annual simulation started from the same initial state on 1 January without data assimilation. The data for the warm period from 1 May to 31 October of each year were used for the following analysis. The model has been validated against in-situ (based on 77867 stations) and night-time satellite monthly mean SST observations. The model also captures well the major features seen on snapshot satellite images. A simulated daily climatology was created by averaging the temperature values over the 34-year simulation. Anomalies were calculated as the deviations of the snapshot temperatures from their climatological values. The correlation between the temperature anomalies of BSW on the outer shelf and those in the CIL waters in the deep sea were computed as well as water transports between these water masses across the shelf break. The BSW on the outer shelf are defined as the waters between the density level σθ=14.2 kg m3 (i.e. the bottom of the surface mixed layer) and the seabed (max z=150 m at the shelf break). The corresponding data from open sea CIL waters in the northwest part of the deep Black Sea were taken from the depth range between σθ=14.2 and z=150 m. The computed Pierson correlation between summer temperatures of BSW and the deep sea CIL is R = 0.90. This significant correlation is in agreement with the analysis from observational data of Shapiro et al. (2011). In order to reveal a physical link between the BSW and CIL, the in-out transports of water with σθ ≥14.2 across the shelf break were computed for each day and then averaged over the warm periods of each year. Over the 34 year time span, the on-shelf and off-shelf transports between the CIL and BSW fluctuate in the range of 0.22 to 0.45 Sv, with the maximum values in 1996 and the minimum in 1990. The net cross-shelf transport is small, approximately 0.03 Sv, due to volume conservation, and is directed off-shore due to river discharges. The years with high values of transport correspond to the situation when a 'channel' of constant PV connecting the BSW and CIL exists, forming a conduit for the waters to move across the shelf break. In the years of reduced transport, there was a PV 'barrier', i.e. a band of significant PV gradient along the shelf break, which inhibits exchanges. The efficiency of the exchange can be represented by the average renewal time of BSW, which is defined as the ratio of BSW volume to the onshore transport. This value, as well as the volumes and the transports vary over the 34 years. The renewal time is within the range between 18 to 42 days. The short renewal time (31 days on average) compared to the seasonal time scales, suggests an efficient exchange between bottom waters on the outer shelf and the CIL in the deep sea during the warm season. This study was partially supported by the EU (via PERSEUS grant FP7-OCEAN-2011-287600 and MyOcean SPA.2011.1.5-01 grant 283367), Institute of Oceanology, Chinese Academy of Sciences and the University of Plymouth Marine Institute Innovation Fund. References Brodeau L., B. Barnier, A.-M. Treguier, T.Penduff, S.Gulev, 2010. An ERA40-based atmospheric forcing for global ocean circulation models, Ocean Modelling, 31 (3-4), 88-104. Kolesnikov, A.G., 1953. Intra-annual variability of temperature, stability and vertical turbulent exchange of heat in the open area of the Black Sea. In: Proceedings of the Marine Hydrophysical Institute, issue 3. Filippov D.M., 1968. Water Circulation and Structure of the Black Sea. Nauka, Moscow, 136 pp. Ivanov, L. I., Besiktepe, S. and E. Özsoy, 1997. The Black Sea Cold Intermediate Layer, in: Özsoy, E. and A. Mikaelyan (editors), Sensitivity to Change: Black Sea, Baltic Sea and North Sea, NATO ASI Series (Partnership Sub-series, Environment, 27), Kluwer Academic Publishers, Dordrecht, 536 pp. Shapiro, G.I., F. Wobus, D.L. Aleynik, 2011. Seasonal and inter-annual temperature variability in the bottom waters over the western Black Sea shelf, Ocean Science 7, 585-596. Shapiro, G., Luneva, M., Pickering, J., and Storkey, D., 2013. The effect of various vertical discretization schemes and horizontal diffusion parameterization on the performance of a 3-D ocean model: the Black Sea case study, Ocean Science, 9, 377-390. Staneva, J. V. and E. V. Stanev, 1997. Cold water mass formation in the Black Sea. Analysis on numerical model simulations. In: E. Ozsoy and A. Mikaelyan (eds.), Sensitivity to change: Black Sea, Baltic Sea and North Sea. NATO ASI Series, Vol. 27, Kluwer Academic Publishers, 375-393.
NASA Astrophysics Data System (ADS)
Winkler, G.; Cabrol, J.; Sage, R.; Nozais, C.; Tremblay, R.; Starr, M.
2016-02-01
The lower St. Lawrence estuary (LSLE) is influenced by river discharge and saltwater inflow. Together with arctic water inflow and ice cover in winter a strong stratification occurs resulting in a cold intermediate layer (CIL) from spring to autumn. This stratification provides thermal habitats. Here, we focus on two krill species Thysanoessa raschii and Meganyctiphanes norvegica that aggregate in the CIL and the warmer deep water layer, respectively. Both species are known to migrate into the surface layer to feed and thus transfering energy through the food web by linking lower with higher trophic levels. However, their specific feeding biology and trophic interactions are poorly understood. We tested the following hypotheses: (1) the diets vary throughout the season depending on food availability, (2) similar to thermal habitat separation, trophic niche separation between T. raschii and M. norvegica occurs, characterized by herbivory in T. raschii and carnivory in M. norvegica. Trophic position and feeding behavior of theses krill populations were monitored throughout one year 2014-2015 using a stable isotope approach. The two species showed a seasonal shift in their trophic position being on a higher trophic level in summer than in spring and autumn, which did not correspond to phytoplankton or zooplankton availability. Within the trophic space of carbon and nitrogen stable isotopes M. norvegica showed a relatively stable position, whereas T. raschii covered a much larger space throughout the year. M. norvegica was always positioned at a higher trophic level than T. raschii. Results of a stable isotope mixing model (SIAR) revealed 50% phytoplankton and 50% copepods in the diet of M. norvegica, while T. raschii showed a higher proportion of ca. 70% phytoplankton in its diet. Both species exploited several trophic levels, but in different proportions, thereby minimizing diet overlap, suggesting a further mechanism to enhance stable co-existence of these krill species in the highly stratified LSLE.
Chen, Huihui; Zhong, Fei; Li, Xiujin; Wang, Lu; Sun, Yan; Neng, Changai; Zhang, Kao; Li, Wenyan; Wen, Jiexia
2012-11-04
To investigate the effects of canine interleukin-2 (cIL-2) and cIL-7 genes on enhancing the immunogenicity of canine parvovirus (CPV) VP2 DNA vaccine. The bicistronic vectors of cIL-2 and cIL-7 genes were constructed using the eukaryotic expression vector containing internal ribosome entry site (IRES). The cIL-2/ cIL-7 dicistronic vector plus previously constructed vectors, including CPV VP2 DNA vaccine vector, cIL-2 vector and cIL-7 vector, were used to co-immunize mice with different combinations, consisting of VP2 alone, VP2 + cIL-2, VP2 + cIL-7 and VP2 + cIL-2/cIL-7. The VP2-specific antibody levels in immunized mice were measured by ELISA at different time post-immunization. The proliferation indices and interferon-gamma expression were measured by lymphocyte proliferation assay and ELISA, respectively. The cIL-2/cIL-7 bicistronic vector was correct and could mediate cIL-2 and cIL-7 gene expression in eukaryotic cells. Immunization results revealed that the antibody titers and the neutralizing antibody levels of the mice co-immunized with VP2 + cIL-7/cIL-2 vectors were significantly higher than that with either VP2 + cIL-2 vectors or VP2 + cIL-7 vectors (P < 0.05). The lymphocyte proliferation indices of VP2 + cIL-7/cIL-2 vector-immunized mice were also higher than that of other two groups although not statistically significant. However, the IFN-gamma expression levels of VP2 + cIL-7/cIL-2 vector-immunized mice were significantly higher than other immunized mice (P < 0.05). The cIL-2 and cIL-7 genes showed the significant synergic effects on enhancing the immunogenecity of CPV VP2 DNA vaccine.
NASA Astrophysics Data System (ADS)
Brown, Linda Lou
Federal educational policy, No Child Left Behind Act of 2001, focused attention on America's education with conspicuous results. One aspect, highly qualified classroom teacher and principal (HQ), was taxing since states established individual accountability structures. The HQ impact and use of data-informed decision-making (DIDM) for Texas elementary science education monitoring by campus administrators, Campus Instruction Leader (CILs), provides crucial relationships to 5th grade students' learning and achievement. Forty years research determined improved student results when sustained, supported, and focused professional development (PD) for teachers is available. Using mixed methods research, this study applied quantitative and qualitative analysis from two, electronic, on-line surveys: Texas Elementary, Intermediate or Middle School Teacher Survey(c) and the Texas Elementary Campus Administrator Survey(c) with results from 22.3% Texas school districts representing 487 elementary campuses surveyed. Participants selected in random, stratified sampling of 5th grade teachers who attended local Texas Regional Collaboratives science professional development (PD) programs between 2003-2008. Survey information compared statistically to campus-level average passing rate scores on the 5th grade science TAKS using Statistical Process Software (SPSS). Written comments from both surveys analyzed with Qualitative Survey Research (NVivo) software. Due to the level of uncertainty of variables within a large statewide study, Mauchly's Test of Sphericity statistical test used to validate repeated measures factor ANOVAs. Although few individual results were statistically significant, when jointly analyzed, striking constructs were revealed regarding the impact of HQ policy applications and elementary CILs use of data-informed decisions on improving 5th grade students' achievement and teachers' PD learning science content. Some constructs included the use of data-warehouse programs; teachers' applications of DIDM to modify lessons for differentiated science instruction, the numbers of years' teachers attended science PD, and teachers' influence on CILs staffing decisions. Yet CILs reported 14% of Texas elementary campuses had limited or no science education programs due to federal policy requirement for reading and mathematics. Three hypothesis components were supported and accepted from research data resulted in two models addressing elementary science, science education PD, and CILs impact for federal policy applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Teng, Chih-Chuan; Chronic Diseases and Health Promotion Research Center, CGUST, Taiwan; Institute of Basic Medicine Science, National Cheng Kung University, Tainan, Taiwan
CIL-102 (1-[4-(furo[2,3-b]quinolin-4-ylamino)phenyl]ethanone), the major active agent of the alkaloid derivative, has been demonstrated to exert anticancer effects. Herein, we present an investigation focused on the identification of the target(s) of CIL-102's action and the mechanism of its action in apoptotic and anti-invasive pathways. Proteomic approaches were used to purify and identify the protein substrates using 2D difference gel electrophoresis (2D SDS-PAGE) to assess changes in the expression of relevant protein treatment with CIL-102 that resulted in the inhibition of viability and invasion. Our results demonstrate that CIL-102 treatment of U87 cells decreased cell proliferation and invasiveness. CIL-102 dose-dependent induction ofmore » apoptosis and inhibitory invasiveness were accompanied by sustained phosphorylation of JNK1/2 and p70S6K as well as generation of the reactive oxygen species. In addition, differential proteins displayed between CIL-102-treated and untreated U87 were determined and validated. There were 11 differentially expressed proteins between the CIL-102-treated and untreated groups. Furthermore, we demonstrated that CIL-102 inhibited cancer cell proliferation and reduced anti-invasion properties by up-regulating the levels of FUMH (Fumarate hydratase). The investigation demonstrated that there was an increase in the cellular levels of FUMH in the CIL-102 reduction in viability and invasion via the activation of JNK1/2 and mTOR signaling modules. NAC administration and shRNA FUMH conferred resistance to CIL-102-inhibited HIF1α and MMP-2 levels via inhibition of JNK1/2 and mTOR activation. We concluded that CIL-102-induced an apoptosis cascade and decreased aggressiveness in astrocytoma cells by modulation of mitochondria function, providing a new mechanism for CIL-102 treatment. - Highlights: • We found the effect of CIL-102 on neuroblastoma cells. • Fumarate hydratase as a CIL-102's target by proteomic differential displays. • CIL-102 regulated-FUMH stimulates apoptosis-related protein and inactivation HIF1.« less
Independent Orbiter Assessment (IOA): Assessment of the elevon actuator subsystem FMEA/CIL
NASA Technical Reports Server (NTRS)
Wilson, R. E.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Elevon Subsystem hardware, generating draft failure modes, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter Elevon hardware. The IOA product for the Elevon analysis consisted of 25 failure mode worksheets that resulted in 17 potential critical items being identified. Comparison was made to the NASA FMEA/CIL, which consisted of 23 FMEAs and 13 CIL items. This comparison produced agreement on all CIL items. Based on the Pre 51-L baseline, all non-CIL FMEAs were also in agreement.
Catalyst containing oxygen transport membrane
Christie, Gervase Maxwell; Wilson, Jamie Robyn; van Hassel, Bart Antonie
2012-12-04
A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a high average pore diameter and the intermediate porous layer has a lower permeability and lower pore diameter than the porous support layer. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.
Independent Orbiter Assessment (IOA) CIL issues resolution report, volume 3
NASA Technical Reports Server (NTRS)
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. This report contains IOA assessment workshets showing resolution of outstanding IOA CIL issues that were summarized in the IOA FMEA/CIL Assessment Interim Report, dated 9 March 1988. Each assessment worksheet has been updated with CIL issue rsolution and rationale. Volume 3 contains the worksheets for the Reaction Control Subsystem and the Communications and Tracking Subsystem.
Independent Orbiter Assessment (IOA): Assessment of the rudder/speed brake subsystem FMEA/CIL
NASA Technical Reports Server (NTRS)
Wilson, R. E.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Rudder/Speed Brake (RSB) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline along with the proposed Post 51-L CIL updates included. A resolution of each discrepancy from the comparison was provided through additional analysis as required. This report documents the results of that comparison for the Orbiter RSB hardware. The IOA product for the RSB analysis consisted of 38 failure mode worksheets that resulted in 27 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 34 FMEAs and 18 CIL items. This comparison produced agreement on all CIL items. Based on the Pre 51-L baseline, all non-CIL FMEAs were also in agreement.
Independent Orbiter Assessment (IOA): FMEA/CIL instructions and ground rules
NASA Technical Reports Server (NTRS)
Traves, S. T.
1986-01-01
The McDonnell Douglas Astronautics Company was selected to conduct an independent assessment of the Orbiter Failure Mode and Effects Analysis/Critical Items List (FMEA/CIL). Part of this effort involved an examination of the FMEA/CIL preparation instructions and ground rules. Assessment objectives were to identify omissions and ambiguities in the ground rules that may impede the identification of shuttle orbiter safety and mission critical items, and to ensure that ground rules allow these items to receive proper management visibility for risk assessment. Assessment objectives were followed during the performance of the assessment without being influenced by external considerations such as effects on budget, schedule, and documentation growth. Assessment personnel were employed who had a strong reliability background but no previous space shuttle FMEA/CIL experience to ensure an independent assessment would be achieved. The following observations were made: (1) not all essential items are in the CIL for management visibility; (2) ground rules omit FMEA/CIL coverage of items that perform critical functions; (3) essential items excluded from the CIL do not receive design justification; and (4) FMEAs/CILs are not updated in a timely manner. In addition to the above issues, a number of other issues were identified that correct FMEA/CIL preparation instruction omissions and clarify ambiguities. The assessment was successful in that many of the issues have significant safety implications.
Independent Orbiter Assessment (IOA): Assessment of the body flap subsystem FMEA/CIL
NASA Technical Reports Server (NTRS)
Wilson, R. E.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Body Flap (BF) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter BF hardware. The IOA product for the BF analysis consisted of 43 failure mode worksheets that resulted in 19 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 34 FMEAs and 15 CIL items. This comparison produced agreement on all CIL items. Based on the Pre 51-L baseline, all non-CIL FMEAs were also in agreement.
Independent Orbiter Assessment (IOA): CIL issues resolution report, volume 2
NASA Technical Reports Server (NTRS)
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes And Effects Analysis (FMEA) and Critical Items List (CIL) are presented. This report contains IOA assessment worksheets showing resolution of outstanding IOA CIL issues that were summarized in the IOA FMEA/CIL Assessment Interim Report, dated 9 March 1988. Each assessment worksheet has been updated with CIL issue resolution and rationale. Volume 2 contains the worksheets for the following subsystems: Nose Wheel Steering Subsystem; Remote Manipulator Subsystem; Atmospheric Revitalization Subsystem; Extravehicular Mobility Unit Subsystem; Power Reactant Supply and Distribution Subsystem; Main Propulsion Subsystem; and Orbital Maneuvering Subsystem.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Teng, Chih-Chuan; Institute of Basic Medicine Science, National Cheng Kung University, Tainan, Taiwan; Kuo, Hsing-Chun
2012-08-15
CIL-102 (1-[4-(furo[2,3-b]quinolin-4-ylamino)phenyl]ethanone) is the major active agent of the alkaloid derivative of Camptotheca acuminata, with multiple pharmacological activities, including anticancer effects and promotion of apoptosis. The mechanism by which CIL-102 inhibits growth remains poorly understood in human astrocytoma cells. Herein, we investigated the molecular mechanisms by which CIL-102 affects the generation of reactive oxygen species (ROS) and cell cycle G2/M arrest in glioma cells. Treatment of U87 cells with 1.0 μM CIL-102 resulted in phosphorylation of extracellular signal-related kinase (ERK1/2), downregulation of cell cycle-related proteins (cyclin A, cyclin B, cyclin D1, and cdk1), and phosphorylation of cdk1Tyr{sup 15} and Cdc25cSer{supmore » 216}. Furthermore, treatment with the ERK1/2 inhibitor PD98059 abolished CIL-102-induced Cdc25cSer{sup 216} expression and reversed CIL-102-inhibited cdk1 activation. In addition, N-acetyl cysteine (NAC), an ROS scavenger, blocked cell cycle G2/M arrest and phosphorylation of ERK1/2 and Cdc25cSer{sup 216} in U87 cells. CIL-102-mediated ERK1/2 and ROS production, and cell cycle arrest were blocked by treatment with specific inhibitors. In conclusion, we have identified a novel CIL-102-inhibited proliferation in U87 cells by activating the ERK1/2 and Cdc25cSer{sup 216} cell cycle-related proteins and inducing ROS production; this might be a new mechanism in human astrocytoma cells. -- Highlights: ► We show the effects of CIL-102 on the G2/M arrest of human astrocytoma cells. ► ROS and the Ras/ERK1/2 triggering pathways are involved in the CIL-102 treatment. ► CIL-102 induces sustained activation of ERK1/2 and Cdc25c and ROS are required.« less
Independent Orbiter Assessment (IOA): CIL issues resolution report, volume 1
NASA Technical Reports Server (NTRS)
Urbanowicz, Kenneth J.; Hinsdale, L. W.; Barnes, J. E.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. This report contains IOA assessment worksheets showing resolution of outstanding IOA CIL issues that were summarized in the IOA FMEA/CIL Assessment Interim Report, dated 9 March 1988. Each assessment worksheet has been updated with CIL issue resolution and rationale. The NASA and Prime Contractor post 51-L FMEA/CIL documentation assessed is believed to be technically accurate and complete. No assessment issues remain that has safety implications. Volume 1 contain worksheets for the following sybsystems: Landing and Deceleration Subsystem; Purge, Vent and Drain Subsystem; Active Thermal Control and Life Support Systems; Crew Equipment Subsystem; Instrumentation Subsystem; Data Processing Subsystem; Atmospheric Revitalization Pressure Control Subsystem; Hydraulics and Water Spray Boiler Subsystem; and Mechanical Actuation Subsystem.
Catalyst containing oxygen transport membrane
Lane, Jonathan A.; Wilson, Jamie R.; Christie, Gervase Maxwell; Petigny, Nathalie; Sarantopoulos, Christos
2017-02-07
A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a microstructure exhibiting substantially uniform pore size distribution as a result of using PMMA pore forming materials or a bi-modal particle size distribution of the porous support layer materials. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.
NASA Technical Reports Server (NTRS)
Odonnell, R. A.; Weissinger, D.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Landing/Deceleration (LDG/DEC) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter LDG/DEC hardware. The IOA product for the LDG/DEC analysis consisted of 259 failure mode worksheets that resulted in 124 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 267 FMEA's and 120 CIL items. This comparison produced agreement on all but 75 FMEA's which caused differences in 51 CIL items.
NASA Technical Reports Server (NTRS)
Wilson, R. E.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Ascent Thrust Vector Control Actuator (ATVD) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter ATVC hardware. The IOA product for the ATVC actuator analysis consisted of 25 failure mode worksheets that resulted in 16 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 21 FMEAs and 13 CIL items. This comparison produced agreement on all CIL items. Based on the Pre 51-L baseline, all non-CIL FMEAs were also in agreement.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bazzarella, Ricardo; Slocum, Alexander H.; Doherty, Tristan
Electrochemical cells and methods of making electrochemical cells are described herein. In some embodiments, an apparatus includes a multi-layer sheet for encasing an electrode material for an electrochemical cell. The multi-layer sheet including an outer layer, an intermediate layer that includes a conductive substrate, and an inner layer disposed on a portion of the conductive substrate. The intermediate layer is disposed between the outer layer and the inner layer. The inner layer defines an opening through which a conductive region of the intermediate layer is exposed such that the electrode material can be electrically connected to the conductive region. Thus,more » the intermediate layer can serve as a current collector for the electrochemical cell.« less
Electrochemical cells and methods of manufacturing the same
Bazzarella, Ricardo; Slocum, Alexander H; Doherty, Tristan; Cross, III, James C
2015-11-03
Electrochemical cells and methods of making electrochemical cells are described herein. In some embodiments, an apparatus includes a multi-layer sheet for encasing an electrode material for an electrochemical cell. The multi-layer sheet including an outer layer, an intermediate layer that includes a conductive substrate, and an inner layer disposed on a portion of the conductive substrate. The intermediate layer is disposed between the outer layer and the inner layer. The inner layer defines an opening through which a conductive region of the intermediate layer is exposed such that the electrode material can be electrically connected to the conductive region. Thus, the intermediate layer can serve as a current collector for the electrochemical cell.
Electrochemical cells and methods of manufacturing the same
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bazzarella, Ricardo; Slocum, Alexander H.; Doherty, Tristan
2016-07-26
Electrochemical cells and methods of making electrochemical cells are described herein. In some embodiments, an apparatus includes a multi-layer sheet for encasing an electrode material for an electrochemical cell. The multi-layer sheet including an outer layer, an intermediate layer that includes a conductive substrate, and an inner layer disposed on a portion of the conductive substrate. The intermediate layer is disposed between the outer layer and the inner layer. The inner layer defines an opening through which a conductive region of the intermediate layer is exposed such that the electrode material can be electrically connected to the conductive region. Thus,more » the intermediate layer can serve as a current collector for the electrochemical cell.« less
Intermediate coating layer for high temperature rubbing seals for rotary regenerators
Schienle, James L.; Strangman, Thomas E.
1995-01-01
A metallic regenerator seal is provided having multi-layer coating comprising a NiCrAlY bond layer, a yttria stabilized zirconia (YSZ) intermediate layer, and a ceramic high temperature solid lubricant surface layer comprising zinc oxide, calcium fluoride, and tin oxide. Because of the YSZ intermediate layer, the coating is thermodynamically stable and resists swelling at high temperatures.
Mori, Yutaka; Aritomi, Shizuka; Niinuma, Kazumi; Nakamura, Tarou; Matsuura, Kenichi; Yokoyama, Junichi; Utsunomiya, Kazunori
2014-01-01
Cilnidipine (Cil), which is an L-/N-type calcium channel blocker (CCB), has been known to provide renal protection by decreasing the activity of the sympathetic nervous system (SNS) and the renin-angiotensin system. In this study, we compared the effects of the combination of Cil and amlodipine (Aml), which is an L-type CCB, with an angiotensin (Ang) II receptor blocker on diabetic cardiorenal damage in spontaneously type 2 diabetic rats. Seventeen-week-old Otsuka Long-Evans Tokushima Fatty rats were randomly assigned to receive Cil, Aml, valsartan (Val), Cil + Val, Aml + Val, or a vehicle (eight rats per group) for 22 weeks. Antihypertensive potencies were nearly equal among the CCB monotherapy groups and the combination therapy groups. The lowering of blood pressure by either treatment did not significantly affect the glycemic variables. However, exacerbations of renal and heart failure were significantly suppressed in rats administered Cil or Val, and additional suppression was observed in those administered Cil + Val. Although Val increased the renin-Ang system, Aml + Val treatment resulted in additional increases in these parameters, while Cil + Val did not show such effects. Furthermore, Cil increased the ratio of Ang-(1-7) to Ang-I, despite the fact that Val and Aml + Val decreased the Ang-(1-7) levels. These actions of Cil + Val might be due to their synergistic inhibitory effect on the activity of the SNS, and on aldosterone secretion through N-type calcium channel antagonism and Ang II receptor type 1 antagonism. Thus, Cil may inhibit the progression of cardiorenal disease in type 2 diabetes patients by acting as an N-type CCB and inhibiting the aldosterone secretion and SNS activation when these drugs were administered in combination with an Ang II receptor blocker.
75 FR 13521 - Centers for Independent Living Program-Training and Technical Assistance
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-22
... DEPARTMENT OF EDUCATION Centers for Independent Living Program--Training and Technical Assistance... for Independent Living Program--Training and Technical Assistance (CIL-TA program). The Assistant... appropriated for the CIL program to provide training and technical assistance to CILs, agencies eligible to...
Independent Orbiter Assessment (IOA): Assessment of the remote manipulator system FMEA/CIL
NASA Technical Reports Server (NTRS)
Tangorra, F.; Grasmeder, R. F.; Montgomery, A. D.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Remote Manipulator System (RMS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were than compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. The results of that comparison for the Orbiter RMS hardware are documented. The IOA product for the RMS analysis consisted of 604 failure mode worksheets that resulted in 458 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 45 FMEAs and 321 CIL items. This comparison produced agreement on all but 154 FMEAs which caused differences in 137 CIL items.
NASA Technical Reports Server (NTRS)
Trahan, W. H.; Odonnell, R. A.; Pietz, K. C.; Drapela, L. J.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Guidance, Navigation, and Control System (GNC) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. The results of that comparison for the Orbiter GNC hardware is documented. The IOA product for the GNC analysis consisted of 141 failure mode worksheets that resulted in 24 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 148 FMEAs and 36 CIL items. This comparison produced agreement on all but 56 FMEAs which caused differences in zero CIL items.
Independent Orbiter Assessment (IOA): Assessment of instrumental subsystem FMEA/CIL
NASA Technical Reports Server (NTRS)
Gardner, J. R.; Addis, A. W.
1988-01-01
The McDonnell Douglas Astronautics Company (MDAC) was selected in June 1986 to perform an Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL). The IOA effort first completed an analysis of the Instrumentation hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline. A resolution of each discrepancy from the comparison is provided through additional analysis as required. The results of that comparison for the Orbiter Instrumentation hardware are documented. The IOA product for Instrumentation analysis consisted of 107 failure mode worksheets that resulted in 22 critical items being identified. Comparison was made to the Pre 51-L NASA baseline with 14 Post 51-L FMEAs added, which consists of 96 FMEAs and 18 CIL items. This comparison produced agreement on all but 25 FMEAs which caused differences in 5 CIL items.
Colopy, Sara A.; Bjorling, Dale E.; Mulligan, William A.; Bushman, Wade
2014-01-01
Background Homeostatic maintenance and repair of the bladder urothelium has been attributed to proliferation of keratin 5-expressing basal cells (K5-BC) with subsequent differentiation into superficial cells. Recent evidence, however, suggests that the intermediate cell layer harbors a population of progenitor cells. We use label-retaining cell (LRC) methodology in conjunction with a clinically relevant model of uropathogenic Escherichia coli (UPEC)-induced injury to characterize urothelial ontogeny during development and in response to diffuse urothelial injury. Results In the developing urothelium, proliferating cells were dispersed throughout the K5-BC and intermediate cells layers, becoming progressively concentrated in the K5-BC layer with age. When 5-bromo-2-deoxyuridine (BrdU) was administered during urothelial development, LRCs in the adult were found within the K5-BC, intermediate, and superficial cell layers, the location dependent upon time of labeling. UPEC inoculation resulted in loss of the superficial cell layer followed by robust proliferation of K5-BCs and intermediate cells. LRCs within the K5-BC and intermediate cell layers proliferated in response to injury. Conclusions Urothelial development and regeneration following injury relies on proliferation of K5-BC and intermediate cells. The existence and proliferation of LRCs within both the K5-BC and intermediate cell layers suggests the presence of two populations of urothelial progenitor cells. PMID:24796293
Independent Orbiter Assessment (IOA): Assessment of the main propulsion subsystem FMEA/CIL, volume 3
NASA Technical Reports Server (NTRS)
Holden, K. A.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Main Propulsion System (MPS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to available data from the Rockwell Downey/NASA JSC FMEA/CIL review. Volume 3 continues the presentation of IOA worksheets and includes the potential critical items list.
Independent Orbiter Assessment (IOA): Assessment of the main propulsion subsystem FMEA/CIL, volume 2
NASA Technical Reports Server (NTRS)
Holden, K. A.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Main Propulsion System (MPS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were than compared to available data from the Rockwell Downey/NASA JSC FMEA/CIL review. Volume 2 continues the presentation of IOA worksheets for MPS hardware items.
Independent Orbiter Assessment (IOA): Assessment of the reaction control system, volume 1
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Hartman, Dan W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the aft and forward Reaction Control System (RCS) hardware, and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter RCS hardware and EPD and C systems. The IOA product for the RCS analysis consisted of 208 hardware and 2064 EPD and C failure mode worksheets that resulted in 141 hardware and 449 EPD and C potential critical items (PCIs) being identified. A comparison was made of the IOA product to the NASA FMEA/CIL baseline. After comparison and discussions with the NASA subsystem manager, 96 hardware issues, 83 of which concern CIL items or PCIs, and 280 EPD and C issues, 158 of which concern CIL items or PCIs, and 280 EPD and C issues, 158 of which concern CIL items or PCIs, remain unresolved. Volume 1 contains the subsystem description, assessment results, and some of the IOA worksheets.
Chiral ionic liquids in chromatographic and electrophoretic separations.
Kapnissi-Christodoulou, Constantina P; Stavrou, Ioannis J; Mavroudi, Maria C
2014-10-10
This report provides an overview of the application of chiral ionic liquids (CILs) in separation technology, and particularly in capillary electrophoresis and both gas and liquid chromatography. There is a large number of CILs that have been synthesized and designed as chiral agents. However, only a few have successfully been applied in separation technology. Even though this application of CILs is still in its early stages, the scientific interest is increasing dramatically. This article is focused on the use of CILs as chiral selectors, background electrolyte additives, chiral ligands and chiral stationary phases in electrophoretic and chromatographic techniques. Different examples of CILs, which contain either a chiral cation, a chiral anion or both, are presented in this review article, and their major advantages along with their potential applications in chiral electrophoretic and chromatographic recognition are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.
Yoo, Ki-Yeon; Kim, In Hye; Cho, Jeong-Hwi; Ahn, Ji Hyeon; Park, Joon Ha; Lee, Jae-Chul; Tae, Hyun-Jin; Kim, Dae Won; Kim, Jong-Dai; Hong, Seongkweon; Won, Moo-Ho; Kang, Il Jun
2016-01-01
In this study, we tried to verify the neuroprotective effect of Chrysanthemum indicum Linne (CIL) extract, which has been used as a botanical drug in East Asia, against ischemic damage and to explore the underlying mechanism involving the anti-inflammatory approach. A gerbil was given CIL extract for 7 consecutive days followed by bilateral carotid artery occlusion to make a cerebral ischemia/reperfusion model. Then, we found that CIL extracts protected pyramidal neurons in the hippocampal CA1 region (CA1) from ischemic damage using neuronal nucleus immunohistochemistry and Fluoro-Jade B histofluorescence. Accordingly, interleukin-13 immunoreactivities in the CA1 pyramidal neurons of CIL-pretreated animals were maintained or increased after cerebral ischemia/reperfusion. These findings indicate that the pre-treatment of CIL can attenuate neuronal damage/death in the brain after cerebral ischemia/reperfusion via an anti-inflammatory approach. PMID:27073380
NASA Astrophysics Data System (ADS)
Ohtsu, Naofumi; Kozuka, Taro; Shibata, Yuga; Yamane, Misao
2017-11-01
Plasma nitriding was explored for improving the thermal stability of a composite hydrogen permeable membrane comprising a Pd coating on Nb substrate. A NbN intermediate layer was formed on the Nb substrate, and the progress of interdiffusion and deterioration of hydrogen absorption behavior after a thermal treatment at 573 and 773 K, respectively, were investigated. The intermediate layer significantly suppressed the interdiffusion between the coating and the substrate. Furthermore, an increase in the NbN concentration of the intermediate layer enhanced the suppression efficiency. However, the hydrogen permeability of the intermediate layer was significantly low, and hence, an increase in NbN concentration further decreased the hydrogen permeability. We concluded that the nitride layer with a high NbN content was unsuitable as an intermediate layer owing to its low hydrogen permeability, while the partial nitride layer with a low NbN content was inefficient in suppressing the interdiffusion.
Independent Orbiter Assessment (IOA): Assessment of the main propulsion subsystem FMEA/CIL, volume 4
NASA Technical Reports Server (NTRS)
Slaughter, B. C.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Main Propulsion System (MPS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were than compared to available data from the Rockwell Downey/NASA JSC FMEA/CIL review. Volume 4 contains the IOA analysis worksheets and the NASA FMEA to IOA worksheet cross reference and recommendations.
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Haufler, W. A.; Marino, A. J.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Orbital Maneuvering System (OMS) hardware and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter OMS hardware. The IOA analysis defined the OMS as being comprised of the following subsystems: helium pressurization, propellant storage and distribution, Orbital Maneuvering Engine, and EPD and C. The IOA product for the OMS analysis consisted of 284 hardware and 667 EPD and C failure mode worksheets that resulted in 160 hardware and 216 EPD and C potential critical items (PCIs) being identified. A comparison was made of the IOA product to the NASA FMEA/CIL baseline which consisted of 101 hardware and 142 EPD and C CIL items.
2013-06-01
In this research, we examine the Naval Sea Logistics Command s Continuous Integrated Logistics Support Targeted Allowancing Technique (CILS TAT) and... the feasibility of program re-implementation. We conduct an analysis of this allowancing method s effectiveness onboard U.S. Navy Ballistic Missile...Defense (BMD) ships, measure the costs associated with performing a CILS TAT, and provide recommendations concerning possible improvements to the
Independent Orbiter Assessment (IOA): Assessment of the data processing system FMEA/CIL
NASA Technical Reports Server (NTRS)
Lowery, H. J.; Haufler, W. A.
1986-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Data Processing System (DPS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. The results of that comparison is documented for the Orbiter DPS hardware.
Group I-III-VI.sub.2 semiconductor films for solar cell application
Basol, Bulent M.; Kapur, Vijay K.
1991-01-01
This invention relates to an improved thin film solar cell with excellent electrical and mechanical integrity. The device comprises a substrate, a Group I-III-VI.sub.2 semiconductor absorber layer and a transparent window layer. The mechanical bond between the substrate and the Group I-III-VI.sub.2 semiconductor layer is enhanced by an intermediate layer between the substrate and the Group I-III-VI.sub.2 semiconductor film being grown. The intermediate layer contains tellurium or substitutes therefor, such as Se, Sn, or Pb. The intermediate layer improves the morphology and electrical characteristics of the Group I-III-VI.sub.2 semiconductor layer.
Independent Orbiter Assessment (IOA): Assessment of the hydraulics/water spray boiler subsystem
NASA Technical Reports Server (NTRS)
Bynum, M. C.; Duval, J. D.; Parkman, W. E.; Davidson, W. R.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Hydraulics/Water Spray Boiler (HYD/WSB) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter HYD/WSB hardware. The IOA product for the HYD/WSB analysis consisted of 447 failure mode worksheets that resulted in 183 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 364 FMEAs and 111 CIL items. This comparison produced agreement on all but 68 FMEAs which caused differences in 23 CIL items.
NASA Technical Reports Server (NTRS)
Mccants, C. N.; Bearrow, M.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Electrical Power Distribution and Control/Electrical Power Generation (EPD and C/EPG) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison was provided through additional analysis as required. The results of that comparison is documented for the Orbiter EPD and C/EPG hardware. The IOA product for the EPD and C/EPG analysis consisted of 263 failure mode worksheets that resulted in 42 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 211 FMEA and 47 CIL items.
Independent Orbiter Assessment (IOA): Assessment of the auxiliary power unit
NASA Technical Reports Server (NTRS)
Barnes, J. E.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Auxiliary Power Unit (APU) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter APU hardware. The IOA product for the APU analysis, covering both APU hardware and APU electrical components, consisted of 344 failure mode worksheets that resulted in 178 potential critical items being identified. A comparison was made of the IOA product to the NASA APU hardware FMEA/CIL baseline which consisted of 184 FMEAs and 57 CIL items. The comparison identified 72 discrepancies.
2013-05-30
In this research, we examine the Naval Sea Logistics Command’s Continuous Integrated Logistics Support-Targeted Allowancing Technique (CILS-TAT) and... the feasibility of program re-implementation. We conduct an analysis of this allowancing method’s effectiveness onboard U.S. Navy Ballistic Missile...Defense (BMD) ships, measure the costs associated with performing a CILS-TAT, and provide recommendations concerning possible improvements to the
NASA Technical Reports Server (NTRS)
Arbet, J. D.; Duffy, R. E.; Barickman, K.; Saiidi, M. J.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Life Support and Airlock Support Systems (LSS and ALSS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. The discrepancies were flagged for potential future resolution. This report documents the results of that comparison for the Orbiter LSS and ALSS hardware. The IOA product for the LSS and ALSS analysis consisted of 511 failure mode worksheets that resulted in 140 potential critical items. Comparison was made to the NASA baseline which consisted of 456 FMEAs and 101 CIL items. The IOA analysis identified 39 failure modes, 6 of which were classified as CIL items, for components not covered by the NASA FMEAs. It was recommended that these failure modes be added to the NASA FMEA baseline. The overall assessment produced agreement on all but 301 FMEAs which caused differences in 111 CIL items.
Kim, In Hye; Lee, Tae-Kyeong; Cho, Jeong Hwi; Lee, Jae-Chul; Park, Joon Ha; Ahn, Ji Hyeon; Shin, Bich-Na; Chen, Bai Hui; Tae, Hyun-Jin; Kim, Yang Hee; Kim, Jong-Dai; Kim, Young-Myeong; Won, Moo-Ho; Kang, Il Jun
2017-01-01
Chrysanthemum indicum Linné extract (CIL) is used in herbal medicine in East Asia. In the present study, gerbils were orally pre-treated with CIL, and changes of antioxidant enzymes including superoxide dismutase (SOD) 1 and SOD2, catalase (CAT) and glutathione peroxidase (GPX) in the hippocampal CA1 region following 5 min of transient cerebral ischemia were investigated and the neuroprotective effect of CIL in the ischemic CA1 region was examined. SOD1, SOD2, CAT and GPX immunoreactivities were observed in the pyramidal cells of the CA1 region and their immunoreactivities were gradually decreased following ischemia-reperfusion and barely detectable at 5 days post-ischemia. CIL pre-treatment significantly increased immunoreactivities of SOD1, CAT and GPX, but not SOD2, in the CA1 pyramidal cells of the sham-operated animals. In addition, SOD1, SOD2, CAT and GPX immunoreactivities in the CA1 pyramidal cells were significantly higher compared with the ischemia-operated animals. Furthermore, it was identified that pre-treatment with CIL protected the CA1 pyramidal cells in the CA1 region using neuronal nuclei immunohistochemistry and Fluoro-Jade B histofluorescence staining; the protected CA1 pyramidal cells were 67.5% compared with the sham-operated animals. In conclusion, oral CIL pre-treatment increased endogenous antioxidant enzymes in CA1 pyramidal cells in the gerbil hippocampus and protected the cells from transient cerebral ischemic insult. This finding suggested that CIL is promising for the prevention of ischemia-induced neuronal damage. PMID:28534982
Observations of an Intermediate Layer During the Coqui II Campaign
NASA Technical Reports Server (NTRS)
Bishop, R. L.; Earle, G. D.; Herrero, F. A.; Bateman, T. T.
2000-01-01
NASA sounding rocket 21.114, launched March 7, 1998, during the Coqui II campaign, provided neutral wind and plasma density measurements of a weak intermediate layer. The layer was centered near 140 km and had an approximate peak plasma density of 2200 cc. The measured winds were typically less than 40 m/s, in agreement with wind shear formation theory and coincident density observations. The data obtained during the flight allow us to explore the plasma density structure and wind field morphology of the intermediate layer. Coupled with simultaneous data from Arecibo Observatory, the upleg and downleg density profiles provide three spatially separated measurements that enable the first detailed investigation of the horizontal extent and variation of an intermediate layer.
NASA Technical Reports Server (NTRS)
Brown, K. L.; Bertsch, P. J.
1987-01-01
Results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Electrical Power Generation/Fuel Cell Powerplant (EPG/FCP) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. A resolution of each discrepancy from the comparison was provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EPG/FCP hardware.
Independent Orbiter Assessment (IOA): Assessment of the EPD and C/remote manipulator system FMEA/CIL
NASA Technical Reports Server (NTRS)
Robinson, W. W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Electrical Power Distribution and Control (EPD and C)/Remote Manipulator System (RMS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA analysis of the EPD and C/RMS hardware initially generated 345 failure mode worksheets and identified 117 Potential Critical Items (PCIs) before starting the assessment process. These analysis results were compared to the proposed NASA Post 51-L baseline of 132 FMEAs and 66 CIL items.
Moone, Rajean Paul; Lightfoot, Elizabeth
2009-01-01
Centers for independent living (CILs) provide critical supports, services, and advocacy for assisting people with disabilities in living independently. As there is a rapidly increasing population of older people with disabilities, many CILs are now considering how to actively engage older adults in their organizations. This study utilized a survey of older people with disabilities to help identify social marketing techniques that community organizations like CILs can use to effectively reach older people with disabilities. Utilizing the components of the social marketing mix in designing outreach efforts, including a critical examination of product, place, price, participants, and partnering, CILs and other community agencies can better reach older adults with disabilities.
Multilayer Article Characterized by Low Coefficient of Thermal Expansion Outer Layer
NASA Technical Reports Server (NTRS)
Lee, Kang N. (Inventor)
2004-01-01
A multilayer article comprises a substrate comprising a ceramic or a silicon-containing metal alloy. The ceramic is a Si-containing ceramic or an oxide ceramic with or without silicon. An outer layer overlies the substrate and at least one intermediate layer is located between the outer layer and thc substrate. An optional bond layer is disposed between thc 1 least one intermediate layer and thc substrate. The at least one intermediate layer may comprise an optional chemical barrier layer adjacent the outer layer, a mullite-containing layer and an optional chemical barrier layer adjacent to the bond layer or substrate. The outer layer comprises a compound having a low coefficient of thermal expansion selected from one of the following systems: rare earth (RE) silicates; at least one of hafnia and hafnia-containing composite oxides; zirconia-containing composite oxides and combinations thereof.
Process for ion-assisted laser deposition of biaxially textured layer on substrate
Russo, R.E.; Reade, R.P.; Garrison, S.M.; Berdahl, P.
1995-07-11
A process for depositing a biaxially aligned intermediate layer over a non-single crystal substrate is disclosed which permits the subsequent deposition thereon of a biaxially oriented superconducting film. The process comprises depositing on a substrate by laser ablation a material capable of being biaxially oriented and also capable of inhibiting the migration of substrate materials through the intermediate layer into such a superconducting film, while simultaneously bombarding the substrate with an ion beam. In a preferred embodiment, the deposition is carried out in the same chamber used to subsequently deposit a superconducting film over the intermediate layer. In a further aspect of the invention, the deposition of the superconducting layer over the biaxially oriented intermediate layer is also carried out by laser ablation with optional additional bombardment of the coated substrate with an ion beam during the deposition of the superconducting film. 8 figs.
Process for ion-assisted laser deposition of biaxially textured layer on substrate
Russo, Richard E.; Reade, Ronald P.; Garrison, Stephen M.; Berdahl, Paul
1995-01-01
A process for depositing a biaxially aligned intermediate layer over a non-single crystal substrate is disclosed which permits the subsequent deposition thereon of a biaxially oriented superconducting film. The process comprises depositing on a substrate by laser ablation a material capable of being biaxially oriented and also capable of inhibiting the migration of substrate materials through the intermediate layer into such a superconducting film, while simultaneously bombarding the substrate with an ion beam. In a preferred embodiment, the deposition is carried out in the same chamber used to subsequently deposit a superconducting film over the intermediate layer. In a further aspect of the invention, the deposition of the superconducting layer over the biaxially oriented intermediate layer is also carried out by laser ablation with optional additional bombardment of the coated substrate with an ion beam during the deposition of the superconducting film.
Bahm, Isabel; Barriga, Elias H; Frolov, Antonina; Theveneau, Eric; Frankel, Paul; Mayor, Roberto
2017-07-01
A fundamental property of neural crest (NC) migration is contact inhibition of locomotion (CIL), a process by which cells change their direction of migration upon cell contact. CIL has been proven to be essential for NC migration in amphibians and zebrafish by controlling cell polarity in a cell contact-dependent manner. Cell contact during CIL requires the participation of the cell adhesion molecule N-cadherin, which starts to be expressed by NC cells as a consequence of the switch between E- and N-cadherins during epithelial-to-mesenchymal transition (EMT). However, the mechanism that controls the upregulation of N-cadherin remains unknown. Here, we show that platelet-derived growth factor receptor alpha (PDGFRα) and its ligand platelet-derived growth factor A (PDGF-A) are co-expressed in migrating cranial NC. Inhibition of PDGF-A/PDGFRα blocks NC migration by inhibiting N-cadherin and, consequently, impairing CIL. Moreover, we identify phosphatidylinositol-3-kinase (PI3K)/AKT as a downstream effector of the PDGFRα cellular response during CIL. Our results lead us to propose PDGF-A/PDGFRα signalling as a tissue-autonomous regulator of CIL by controlling N-cadherin upregulation during EMT. Finally, we show that once NC cells have undergone EMT, the same PDGF-A/PDGFRα works as an NC chemoattractant, guiding their directional migration. © 2017. Published by The Company of Biologists Ltd.
A novel method to study contact inhibition of locomotion using micropatterned substrates
Scarpa, Elena; Roycroft, Alice; Theveneau, Eric; Terriac, Emmanuel; Piel, Matthieu; Mayor, Roberto
2013-01-01
Summary The concept of contact inhibition of locomotion (CIL) describes the ability of a cell to change the direction of its movement after contact with another cell. It has been shown to be responsible for physiological and developmental processes such as wound healing, macrophage dispersion and neural crest cell migration; whereas its loss facilitates cancer cell invasion and metastatic dissemination. Different assays have been developed to analyze CIL in tissue culture models. However, these methods have several caveats. Collisions happen at low frequency between freely migrating cells and the orientation of the cells at the time of contact is not predictable. Moreover, the computational analysis required by these assays is often complicated and it retains a certain degree of discretion. Here, we show that confinement of neural crest cell migration on a single dimension by using a micropatterned substrate allows standardized and predictable cell–cell collision. CIL can thus easily be quantified by direct measurement of simple cellular parameters such as the distance between nuclei after collision. We tested some of the signaling pathways previously identified as involved in CIL, such as small GTPases and non-canonical Wnt signaling, using this new method for CIL analysis. The restricted directionality of migration of cells in lines is a powerful strategy to obtain higher predictability and higher efficiency of the CIL response upon cell–cell collisions. PMID:24143276
NASA Astrophysics Data System (ADS)
Reade, R. P.; Mao, X. L.; Russo, R. E.
1991-08-01
The use of an intermediate layer is necessary for the growth of YBaCuO thin films on polycrystalline metallic alloys for tape conductor applications. A pulsed laser deposition process to grow controlled-orientation yttria-stabilized zirconia (YSZ) films as intermediate layers on Haynes Alloy No. 230 was developed and characterized. YBaCuO films deposited on these YSZ-coated substrates are primarily c-axis oriented and superconducting as deposited. The best YBaCuO films grow on (001)-oriented YSZ intermediate layers and have Tc (R = 0) = 86.0 K and Jc about 3000 A/sq cm at 77 K.
Independent Orbiter Assessment (IOA): Assessment of the manned maneuvering unit
NASA Technical Reports Server (NTRS)
Huynh, M.; Duffy, R. E.; Saiidi, M. J.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Manned Maneuvering Unit (MMU) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contain within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Martin Marietta FMEA/CIL Post 51-L updates. A discussion of each discrepancy from the comparison is provided through additional analysis as required. These discrepancies were flagged as issues, and recommendations were made based on the FMEA data available at the time. The results of this comparison for the Orbiter MMU hardware are documented. The IOA product for the MMU analysis consisted of 204 failure mode worksheets that resulted in 95 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 179 FMEAs and 110 CIL items. This comparison produced agreement on all 121 FMEAs which caused differences in 92 CIL items.
Effect of intermediate layers on atomic layer deposition-aluminum oxide protected silver mirrors
NASA Astrophysics Data System (ADS)
Fryauf, David M.; Diaz Leon, Juan J.; Phillips, Andrew C.; Kobayashi, Nobuhiko P.
2017-07-01
This work investigates intermediate materials deposited between silver (Ag) thin-film mirrors and an aluminum oxide (AlOx) barrier overlayer and compares the effects on mirror durability to environmental stresses. Physical vapor deposition of various fluorides, oxides, and nitrides in combination with AlOx by atomic layer deposition (ALD) is used to develop several coating recipes. Ag-AlOx samples with different intermediate materials undergo aggressive high-temperature (80°C), high-humidity (80%) (HTHH) testing for 10 days. Reflectivity of mirror samples is measured before and after HTHH testing, and image processing techniques are used to analyze the specular surface of the samples after HTHH testing. Among the seven intermediate materials used in this work, TiN, MgAl2O4, NiO, and Al2O3 intermediate layers offer more robust protection against chemical corrosion and moisture when compared with samples with no intermediate layer. In addition, results show that the performance of the ALD-AlOx barrier overlayer depends significantly on the ALD-growth process temperature. Because higher durability is observed in samples with less transparent TiN and NiO layers, we propose a figure of merit based on post-HTHH testing reflectivity change and specular reflective mirror surface area remaining after HTHH testing to judge overall barrier performance.
NASA Astrophysics Data System (ADS)
Li, Guijun; Ho, Jacob Y. L.; Li, He; Kwok, Hoi-Sing
2014-06-01
Light management through the intermediate reflector in the tandem cell configuration is of great practical importance for achieving high stable efficiency and also low cost production. So far, however, the intermediate reflectors employed currently are mainly focused on the light absorption enhancement of the top cell. Here, we present a diffractive intermediate layer that allows for light trapping over a broadband wavelength for the ultrathin c-Si tandem solar cell. Compared with the standard intermediate reflector, this nanoscale architectural intermediate layer results in a 35% and 21% remarkable enhancement of the light absorption in the top (400-800 nm) and bottom (800-1100 nm) cells simultaneously, and ultrathin c-Si tandem cells with impressive conversion efficiency of 13.3% are made on the glass substrate.
Chia, Hao-Chung; Sheu, Hwo-Shuenn; Hsiao, Yu-Yun; Li, Shao-Sian; Lan, Yi-Kang; Lin, Chung-Yao; Chang, Je-Wei; Kuo, Yen-Chien; Chen, Chia-Hao; Weng, Shih-Chang; Su, Chun-Jen; Su, An-Chung; Chen, Chun-Wei; Jeng, U-Ser
2017-10-25
We have identified an often observed yet unresolved intermediate structure in a popular processing with dimethylformamide solutions of lead chloride and methylammonium iodide for perovskite solar cells. With subsecond time-resolved grazing-incidence X-ray scattering and X-ray photoemission spectroscopy, supplemental with ab initio calculation, the resolved intermediate structure (CH 3 NH 3 ) 2 PbI 2 Cl 2 ·CH 3 NH 3 I features two-dimensional (2D) perovskite bilayers of zigzagged lead-halide octahedra and sandwiched CH 3 NH 3 I layers. Such intermediate structure reveals a hidden correlation between the intermediate phase and the composition of the processing solution. Most importantly, the 2D perovskite lattice of the intermediate phase is largely crystallographically aligned with the [110] planes of the three-dimensional perovskite cubic phase; consequently, with sublimation of Cl ions from the organo-lead octahedral terminal corners in prolonged annealing, the zigzagged octahedral layers of the intermediate phase can merge with the intercalated methylammonium iodide layers for templated growth of perovskite crystals. Regulated by annealing temperature and the activation energies of the intermediate and perovskite, deduced from analysis of temperature-dependent structural kinetics, the intermediate phase is found to selectively mature first and then melt along the layering direction for epitaxial conversion into perovskite crystals. The unveiled epitaxial conversion under growth kinetics controls might be general for solution-processed and intermediate-templated perovskite formation.
Dilute group III-V nitride intermediate band solar cells with contact blocking layers
Walukiewicz, Wladyslaw; Yu, Kin Man
2015-02-24
An intermediate band solar cell (IBSC) is provided including a p-n junction based on dilute III-V nitride materials and a pair of contact blocking layers positioned on opposite surfaces of the p-n junction for electrically isolating the intermediate band of the p-n junction by blocking the charge transport in the intermediate band without affecting the electron and hole collection efficiency of the p-n junction, thereby increasing open circuit voltage (V.sub.OC) of the IBSC and increasing the photocurrent by utilizing the intermediate band to absorb photons with energy below the band gap of the absorber layers of the IBSC. Hence, the overall power conversion efficiency of a IBSC will be much higher than an conventional single junction solar cell. The p-n junction absorber layers of the IBSC may further have compositionally graded nitrogen concentrations to provide an electric field for more efficient charge collection.
Dilute Group III-V nitride intermediate band solar cells with contact blocking layers
Walukiewicz, Wladyslaw [Kensington, CA; Yu, Kin Man [Lafayette, CA
2012-07-31
An intermediate band solar cell (IBSC) is provided including a p-n junction based on dilute III-V nitride materials and a pair of contact blocking layers positioned on opposite surfaces of the p-n junction for electrically isolating the intermediate band of the p-n junction by blocking the charge transport in the intermediate band without affecting the electron and hole collection efficiency of the p-n junction, thereby increasing open circuit voltage (V.sub.OC) of the IBSC and increasing the photocurrent by utilizing the intermediate band to absorb photons with energy below the band gap of the absorber layers of the IBSC. Hence, the overall power conversion efficiency of a IBSC will be much higher than an conventional single junction solar cell. The p-n junction absorber layers of the IBSC may further have compositionally graded nitrogen concentrations to provide an electric field for more efficient charge collection.
32 CFR 887.4 - Requesting CILs.
Code of Federal Regulations, 2010 CFR
2010-07-01
...: Persons authorized CILs may be assisted in their request by the Customer Service Unit (DPMAC) in the... 180 (SF 180), Request Pertaining to Military Records, should be used by persons who had service as...
Independent Orbiter Assessment (IOA): Assessment of the backup flight system FMEA/CIL
NASA Technical Reports Server (NTRS)
Prust, E. E.; Ewell, J. J., Jr.; Hinsdale, L. W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Backup Flight System (BFS) hardware, generating draft failure modes and Potential Critical Items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed NASA Post 51-L FMEA/CIL baseline. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter BFS hardware. The IOA product for the BFS analysis consisted of 29 failure mode worksheets that resulted in 21 Potential Critical Items (PCI) being identified. This product was originally compared with the proposed NASA BFS baseline and subsequently compared with the applicable Data Processing System (DPS), Electrical Power Distribution and Control (EPD and C), and Displays and Controls NASA CIL items. The comparisons determined if there were any results which had been found by the IOA but were not in the NASA baseline. The original assessment determined there were numerous failure modes and potential critical items in the IOA analysis that were not contained in the NASA BFS baseline. Conversely, the NASA baseline contained three FMEAs (IMU, ADTA, and Air Data Probe) for CIL items that were not identified in the IOA product.
Independent Orbiter Assessment (IOA): FMEA/CIL assessment
NASA Technical Reports Server (NTRS)
Hinsdale, L. W.; Swain, L. J.; Barnes, J. E.
1988-01-01
The McDonnell Douglas Astronautics Company (MDAC) was selected to perform an Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL). Direction was given by the Orbiter and GFE Projects Office to perform the hardware analysis and assessment using the instructions and ground rules defined in NSTS 22206. The IOA analysis featured a top-down approach to determine hardware failure modes, criticality, and potential critical items. To preserve independence, the analysis was accomplished without reliance upon the results contained within the NASA and Prime Contractor FMEA/CIL documentation. The assessment process compared the independently derived failure modes and criticality assignments to the proposed NASA post 51-L FMEA/CIL documentation. When possible, assessment issues were discussed and resolved with the NASA subsystem managers. Unresolved issues were elevated to the Orbiter and GFE Projects Office manager, Configuration Control Board (CCB), or Program Requirements Control Board (PRCB) for further resolution. The most important Orbiter assessment finding was the previously unknown stuck autopilot push-button criticality 1/1 failure mode. The worst case effect could cause loss of crew/vehicle when the microwave landing system is not active. It is concluded that NASA and Prime Contractor Post 51-L FMEA/CIL documentation assessed by IOA is believed to be technically accurate and complete. All CIL issues were resolved. No FMEA issues remain that have safety implications. Consideration should be given, however, to upgrading NSTS 22206 with definitive ground rules which more clearly spell out the limits of redundancy.
Architectures and criteria for the design of high efficiency organic photovoltaic cells
Rand, Barry; Forrest, Stephen R; Burk, Diana Pendergrast
2015-03-24
An organic photovoltaic cell includes an anode and a cathode, and a plurality of organic semiconductor layers between the anode and the cathode. At least one of the anode and the cathode is transparent. Each two adjacent layers of the plurality of organic semiconductor layers are in direct contact. The plurality of organic semiconductor layers includes an intermediate layer consisting essentially of a photoconductive material, and two sets of at least three layers. A first set of at least three layers is between the intermediate layer and the anode. Each layer of the first set consists essentially of a different organic semiconductor material having a higher LUMO and a higher HOMO, relative to the material of an adjacent layer of the plurality of organic semiconductor layers closer to the cathode. A second set of at least three layers is between the intermediate layer and the cathode. Each layer of the second set consists essentially of a different organic semiconductor material having a lower LUMO and a lower HOMO, relative to the material of an adjacent layer of the plurality of organic semiconductor layers closer to the anode.
NASA Technical Reports Server (NTRS)
Ames, B. E.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) is presented. The IOA effort first completed an analysis of the Electrical Power Generation/Power Reactant Storage and Distribution (EPG/PRSD) subsystem hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baselines with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. The results of that comparison are documented for the Orbiter EPG/PRSD hardware. The comparison produced agreement on all but 27 FMEAs and 9 CIL items. The discrepancy between the number of IOA findings and NASA FMEAs can be partially explained by the different approaches used by IOA and NASA to group failure modes together to form one FMEA. Also, several IOA items represented inner tank components and ground operations failure modes which were not in the NASA baseline.
NASA Technical Reports Server (NTRS)
Long, W. C.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed and analysis of the Communication and Tracking hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter Communication and Tracking hardware. The IOA product for the Communication and Tracking consisted of 1,108 failure mode worksheets that resulted in 298 critical items being identified. Comparison was made to the NASA baseline which consists of 697 FMEAs and 239 CIL items. The comparison determined if there were any results which had been found by IOA but were not in the NASA baseline. This comparison produced agreement on all but 407 FMEAs which caused differences in 294 CIL items. Volume 1 contains the subsystem description, assessment results, ground rules and assumptions, and some of the IOA worksheets.
Analysis of circadian properties and healthy levels of blue light from smartphones at night.
Oh, Ji Hye; Yoo, Heeyeon; Park, Hoo Keun; Do, Young Rag
2015-06-18
This study proposes representative figures of merit for circadian and vision performance for healthy and efficient use of smartphone displays. The recently developed figures of merit for circadian luminous efficacy of radiation (CER) and circadian illuminance (CIL) related to human health and circadian rhythm were measured to compare three kinds of commercial smartphone displays. The CIL values for social network service (SNS) messenger screens from all three displays were higher than 41.3 biolux (blx) in a dark room at night, and the highest CIL value reached 50.9 blx. These CIL values corresponded to melatonin suppression values (MSVs) of 7.3% and 11.4%, respectively. Moreover, smartphone use in a bright room at night had much higher CIL and MSV values (58.7 ~ 105.2 blx and 15.4 ~ 36.1%, respectively). This study also analyzed the nonvisual and visual optical properties of the three smartphone displays while varying the distance between the screen and eye and controlling the brightness setting. Finally, a method to possibly attenuate the unhealthy effects of smartphone displays was proposed and investigated by decreasing the emitting wavelength of blue LEDs in a smartphone LCD backlight and subsequently reducing the circadian effect of the display.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mashooq, Kishwar; Talukder, Muhammad Anisuzzaman, E-mail: anis@eee.buet.ac.bd
2016-05-21
Although ultra-thin-film solar cells can be attractive in reducing the cost, they suffer from low absorption as the thickness of the active layer is usually much smaller than the wavelength of incident light. Different nano-photonic techniques, including plasmonic structures, are being explored to increase the light absorption in ultra-thin-film solar cells. More than one layer of active materials with different energy bandgaps can be used in tandem to increase the light absorption as well. However, due to different amount of light absorption in different active layers, photo-generated currents in different active layers will not be the same. The current mismatchmore » between the tandem layers makes them ineffective in increasing the efficiency. In this work, we investigate the light absorption properties of tandem solar cells with two ultra-thin active layers working as two subcells and a metal layer with periodically perforated holes in-between the two subcells. While the metal layer helps to overcome the current mismatch, the periodic holes increase the absorption of incident light by helping extraordinary optical transmission of the incident light from the top to the bottom subcell, and by coupling the incident light to plasmonic and photonic modes within ultra-thin active layers. We extensively study the effects of the geometry of holes in the intermediate metal layer on the light absorption properties of tandem solar cells with ultra-thin active layers. We also study how different metals in the intermediate layer affect the light absorption; how the geometry of holes in the intermediate layer affects the absorption when the active layer materials are changed; and how the intermediate metal layer affects the collection of photo-generated electron-hole pairs at the terminals. We find that in a solar cell with 6,6-phenyl C61-butyric acid methyl ester top subcell and copper indium gallium selenide bottom subcell, if the periodic holes in the metal layer are square or polygon, total absorption remains approximately the same. However, the total absorption suffers significantly if the holes are triangle. The transmission spectra of incident light into the bottom subcell, and hence the absorption, change significantly for square and circle holes if the active materials change to cadmium selenide (CdSe) and cadmium telluride (CdTe) in the top and bottom subcells, respectively. Although the intermediate metal layer may induce electron-hole pair recombination due to surface defects, the short-circuit current density of an ultra-thin plasmonic solar cell with an intermediate metal layer with two-dimensional hole array is >9% of that of a structure without the intermediate metal layer.« less
Independent Orbiter Assessment (IOA): Assessment of the active thermal control system
NASA Technical Reports Server (NTRS)
Sinclair, S. K.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Active Thermal Control System (ATCS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the available NASA FMEA/CIL data. Discrepancies from the comparison were documented, and where enough information was available, recommendations for resolution of the discrepancies were made. This report documents the results of that comparison for the Orbiter ATCS hardware. The IOA product for the ATCS independent analysis consisted of 310 failure mode worksheets that resulted in 101 potential critical items (PCI) being identified. A comparison was made to the available NASA data which consisted of 252 FMEAs and 109 CIL items.
NASA Technical Reports Server (NTRS)
Saiidi, M. J.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the atmospheric Revitalization Pressure Control Subsystem (ARPCS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL proposed Post 51-L updates based upon the CCB/PRCB presentations and an informal criticality summary listing. A discussion of each discrepancy from the comparison is provided through additional analysis as required. These discrepancies were flagged as issues, and recommendations were made based on the FMEA data available at the time. This report documents the results of that comparison for the Orbiter ARPCS hardware.
Independent Orbiter Assessment (IOA): Assessment of the crew equipment subsystem
NASA Technical Reports Server (NTRS)
Saxon, H.; Richard, Bill; Sinclair, S. K.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Crew Equipment hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter Crew Equipment hardware. The IOA product for the Crew Equipment analysis consisted of 352 failure mode worksheets that resulted in 78 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 351 FMEAs and 82 CIL items.
Failure mode and effects analysis (FMEA) for the Space Shuttle solid rocket motor
NASA Technical Reports Server (NTRS)
Russell, D. L.; Blacklock, K.; Langhenry, M. T.
1988-01-01
The recertification of the Space Shuttle Solid Rocket Booster (SRB) and Solid Rocket Motor (SRM) has included an extensive rewriting of the Failure Mode and Effects Analysis (FMEA) and Critical Items List (CIL). The evolution of the groundrules and methodology used in the analysis is discussed and compared to standard FMEA techniques. Especially highlighted are aspects of the FMEA/CIL which are unique to the analysis of an SRM. The criticality category definitions are presented and the rationale for assigning criticality is presented. The various data required by the CIL and contribution of this data to the retention rationale is also presented. As an example, the FMEA and CIL for the SRM nozzle assembly is discussed in detail. This highlights some of the difficulties associated with the analysis of a system with the unique mission requirements of the Space Shuttle.
Analysis of circadian properties and healthy levels of blue light from smartphones at night
Oh, Ji Hye; Yoo, Heeyeon; Park, Hoo Keun; Do, Young Rag
2015-01-01
This study proposes representative figures of merit for circadian and vision performance for healthy and efficient use of smartphone displays. The recently developed figures of merit for circadian luminous efficacy of radiation (CER) and circadian illuminance (CIL) related to human health and circadian rhythm were measured to compare three kinds of commercial smartphone displays. The CIL values for social network service (SNS) messenger screens from all three displays were higher than 41.3 biolux (blx) in a dark room at night, and the highest CIL value reached 50.9 blx. These CIL values corresponded to melatonin suppression values (MSVs) of 7.3% and 11.4%, respectively. Moreover, smartphone use in a bright room at night had much higher CIL and MSV values (58.7 ~ 105.2 blx and 15.4 ~ 36.1%, respectively). This study also analyzed the nonvisual and visual optical properties of the three smartphone displays while varying the distance between the screen and eye and controlling the brightness setting. Finally, a method to possibly attenuate the unhealthy effects of smartphone displays was proposed and investigated by decreasing the emitting wavelength of blue LEDs in a smartphone LCD backlight and subsequently reducing the circadian effect of the display. PMID:26085126
Analysis of circadian properties and healthy levels of blue light from smartphones at night
NASA Astrophysics Data System (ADS)
Oh, Ji Hye; Yoo, Heeyeon; Park, Hoo Keun; Do, Young Rag
2015-06-01
This study proposes representative figures of merit for circadian and vision performance for healthy and efficient use of smartphone displays. The recently developed figures of merit for circadian luminous efficacy of radiation (CER) and circadian illuminance (CIL) related to human health and circadian rhythm were measured to compare three kinds of commercial smartphone displays. The CIL values for social network service (SNS) messenger screens from all three displays were higher than 41.3 biolux (blx) in a dark room at night, and the highest CIL value reached 50.9 blx. These CIL values corresponded to melatonin suppression values (MSVs) of 7.3% and 11.4%, respectively. Moreover, smartphone use in a bright room at night had much higher CIL and MSV values (58.7 ~ 105.2 blx and 15.4 ~ 36.1%, respectively). This study also analyzed the nonvisual and visual optical properties of the three smartphone displays while varying the distance between the screen and eye and controlling the brightness setting. Finally, a method to possibly attenuate the unhealthy effects of smartphone displays was proposed and investigated by decreasing the emitting wavelength of blue LEDs in a smartphone LCD backlight and subsequently reducing the circadian effect of the display.
CIL: Compiler Implementation Language
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gries, David
1969-03-01
This report is a manual for the proposed Compiler Implementation Language, CIL. It is not an expository paper on the subject of compiler writing or compiler-compilers. The language definition may change as work progresses on the project. It is designed for writing compilers for the IBM 360 computers.
Independent Orbiter Assessment (IOA): FMEA/CIL assessment
NASA Technical Reports Server (NTRS)
Saiidi, Mo J.; Swain, L. J.; Compton, J. M.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. Direction was given by the Orbiter and GFE Projects Office to perform the hardware analysis and assessment using the instructions and ground rules defined in NSTS 22206. The IOA analysis features a top-down approach to determine hardware failure modes, criticality, and potential critical items. To preserve independence, the anlaysis was accomplished without reliance upon the results contained within the NASA and prime contractor FMEA/CIL documentation. The assessment process compares the independently derived failure modes and criticality assignments to the proposed NASA Post 51-L FMEA/CIL documentation. When possible, assessment issues are discussed and resolved with the NASA subsystem managers. The assessment results for each subsystem are summarized. The most important Orbiter assessment finding was the previously unknown stuck autopilot push-button criticality 1/1 failure mode, having a worst case effect of loss of crew/vehicle when a microwave landing system is not active.
Lin, Benjamin; Yin, Taofei; Wu, Yi I.; Inoue, Takanari; Levchenko, Andre
2015-01-01
Directed cell migration in native environments is influenced by multiple migratory cues. These cues may include simultaneously occurring attractive soluble growth factor gradients and repulsive effects arising from cell-cell contact, termed contact inhibition of locomotion (CIL). How single cells reconcile potentially conflicting cues remains poorly understood. Here we show that a dynamic crosstalk between epidermal growth factor (EGF) mediated chemotaxis and CIL guide metastatic breast cancer cell motility, whereby cells become progressively insensitive to CIL in a chemotactic input-dependent manner. This balance is determined via integration of protrusion-enhancing signaling from EGF gradients and protrusion-suppressing signaling induced by CIL, mediated in part through EphB. Our results further suggest that EphB and EGF signaling inputs control protrusion formation by converging onto regulation of phosphatidylinositol 3-kinase (PI3K). We propose that this intricate interplay may enhance the spread of loose cell ensembles in pathophysiological conditions such as cancer, and possibly other physiological settings. PMID:25851023
Scarpa, Elena; Szabó, András; Bibonne, Anne; Theveneau, Eric; Parsons, Maddy; Mayor, Roberto
2015-08-24
Contact inhibition of locomotion (CIL) is the process through which cells move away from each other after cell-cell contact, and it contributes to malignant invasion and developmental migration. Various cell types exhibit CIL, whereas others remain in contact after collision and may form stable junctions. To investigate what determines this differential behavior, we study neural crest cells, a migratory stem cell population whose invasiveness has been likened to cancer metastasis. By comparing pre-migratory and migratory neural crest cells, we show that the switch from E- to N-cadherin during EMT is essential for acquisition of CIL behavior. Loss of E-cadherin leads to repolarization of protrusions, via p120 and Rac1, resulting in a redistribution of forces from intercellular tension to cell-matrix adhesions, which break down the cadherin junction. These data provide insight into the balance of physical forces that contributes to CIL in cells in vivo. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
Scarpa, Elena; Szabó, András; Bibonne, Anne; Theveneau, Eric; Parsons, Maddy; Mayor, Roberto
2015-01-01
Summary Contact inhibition of locomotion (CIL) is the process through which cells move away from each other after cell-cell contact, and it contributes to malignant invasion and developmental migration. Various cell types exhibit CIL, whereas others remain in contact after collision and may form stable junctions. To investigate what determines this differential behavior, we study neural crest cells, a migratory stem cell population whose invasiveness has been likened to cancer metastasis. By comparing pre-migratory and migratory neural crest cells, we show that the switch from E- to N-cadherin during EMT is essential for acquisition of CIL behavior. Loss of E-cadherin leads to repolarization of protrusions, via p120 and Rac1, resulting in a redistribution of forces from intercellular tension to cell-matrix adhesions, which break down the cadherin junction. These data provide insight into the balance of physical forces that contributes to CIL in cells in vivo. PMID:26235046
Emelyanenko, A V; Osipov, M A
2003-11-01
A general phenomenological description and a simple molecular model is proposed for the "discrete" flexoelectric effect in tilted smectic liquid crystal phases. This effect defines a polarization in a smectic layer induced by a difference of director orientations in the two smectic layers adjacent to it. It is shown that the "discrete" flexoelectric effect is determined by electrostatic dipole-quadrupole interaction between positionally correlated molecules located in adjacent smectic layers, while the corresponding dipole-dipole interaction is responsible for a coupling between polarization vectors in neighboring layers. It is shown that a simple phenomenological model of a ferrielectric smectic liquid crystal, which has recently been proposed in the literature, can be used to describe the whole sequence of intermediate chiral smectic C* phases with increasing periods, and to determine the nonplanar structure of each phase without additional assumptions. In this sequence the phases with three- and four-layer periodicities have the same structure, as observed in the experiment. The theory predicts also the structure of intermediate phases with longer periods that have not been studied experimentally so far. The structures of intermediate phases with periodicities of up to nine layers are presented together with the phase diagrams, and a relationship between molecular chirality and the three-dimensional structure of intermediate phases is discussed. It is considered also how the coupling between the spontaneous polarization determined by molecular chirality and the induced polarization determined by the discrete flexoelectric effect stabilizes the nonplanar structure of intermediate phases.
Independent Orbiter Assessment (IOA): Assessment of the nose wheel steering subsystem
NASA Technical Reports Server (NTRS)
Mediavilla, Anthony Scott
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Nose Wheel Steering (NWS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed NASA post 51-L FMEA/CIL baseline. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter NWS hardware.
32 CFR 887.2 - Safeguarding certificates.
Code of Federal Regulations, 2010 CFR
2010-07-01
... National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE MILITARY PERSONNEL ISSUING... costly to the Air Force. To keep requests for CILs at a minimum: (a) Personnel officers will tell members of the importance of safeguarding the original certificates. (b) Persons who issue CILs will type or...
NASA Astrophysics Data System (ADS)
Sohn, Kyung-Rak; Song, Jae-Won
2002-03-01
Using a side-polished single-mode fiber covered with a polished LiNbO 3 overlay and an intermediate coupling layer, tunable fiber-optic comb filters are demonstrated. The device behaviors based on the modal properties of the fiber and the planar LiNbO 3 waveguide are analyzed by two dimensional beam propagation methods (2-D BPM) and discussed the role of an intermediate coupling layer in terms of coupling efficiency. We also show that the thermo-optic effects of this layer can be utilized to tune the comb filter. When the polished x-cut LiNbO 3 with 200 μm thickness is used as a multimode overlay waveguide, the comb output spectra with free spectral range of 4 nm are measured in 1550 nm wavelength range. The tuning rate as a function of the refractive index of an intermediate coupling layer, Δλ/ Δnb, is about -0.129 nm/-0.001. The experimental results are in good agreement with the calculated results.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Itoi, Takaomi, E-mail: itoi@faculty.chiba-u.jp
An Al sheet and a Ni-coated Cu sheet were lap joined by using magnetic pulse welding (MPW). Tensile tests were performed on the joined sheets, and a good lap joint was achieved at a discharge energy of > 0.9 kJ. The weld interface exhibited a wavy morphology and an intermediate layer along the weld interface. Microstructure observations of the intermediate layer revealed that the Ni coating region consisted of a Ni–Al binary amorphous alloy and that the Al sheet region contained very fine Al nanograins. Ni fragments indicative of unmelted residual Ni from the coating were also observed in partsmore » of the intermediate layer. Formation of these features can be attributed to localize melting and a subsequent high rate cooling of molten Al and Ni confined to the interface during the MPW process. In the absence of an oxide film, atomic-scale bonding was also achieved between the intermediate layer and the sheet surfaces after the collision. MPW utilises impact energy, which affects the sheet surfaces. From the obtained results, good lap joint is attributed to an increased contact area, the anchor effect, work hardening, the absence of an oxide film, and suppressed formation of intermetallic compounds at the interface. - Highlights: •Good lap joint of an Al sheet and a Ni-coated Cu sheet was achieved by using magnetic pulse welding. •A Ni–Al binary amorphous alloy was formed as an intermediate layer at weld interface. •Atomic-scale bonding was achieved between the intermediate layer and the sheet surfaces.« less
Independent Orbiter Assessment (IOA): Assessment of the extravehicular mobility unit, volume 1
NASA Technical Reports Server (NTRS)
Raffaelli, Gary G.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort performed an independent analysis of the Extravehicular Mobility Unit (EMU) hardware and system, generating draft failure modes criticalities and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were than compared to the most recent proposed Post 51-L NASA FMEA/CIL baseline. A resolution of each discrepancy from the comparison was provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EMU hardware.
34 CFR 366.2 - What agencies are eligible for assistance under the CIL program?
Code of Federal Regulations, 2011 CFR
2011-07-01
... 34 Education 2 2011-07-01 2010-07-01 true What agencies are eligible for assistance under the CIL program? 366.2 Section 366.2 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION CENTERS FOR...
34 CFR 366.1 - What is the Centers for Independent Living (CIL) program?
Code of Federal Regulations, 2011 CFR
2011-07-01
... 34 Education 2 2011-07-01 2010-07-01 true What is the Centers for Independent Living (CIL) program? 366.1 Section 366.1 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION CENTERS FOR INDEPENDENT...
34 CFR 366.2 - What agencies are eligible for assistance under the CIL program?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 34 Education 2 2010-07-01 2010-07-01 false What agencies are eligible for assistance under the CIL program? 366.2 Section 366.2 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION CENTERS FOR...
34 CFR 366.1 - What is the Centers for Independent Living (CIL) program?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 34 Education 2 2010-07-01 2010-07-01 false What is the Centers for Independent Living (CIL) program? 366.1 Section 366.1 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION CENTERS FOR...
NASA Technical Reports Server (NTRS)
Schmeckpeper, K. R.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA first completed an analysis of the Electrical Power Distribution and Control (EPD and C) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EPD and C hardware. The IOA product for the EPD and C analysis consisted of 1671 failure mode analysis worksheets that resulted in 468 potential critical items being identified. Comparison was made to the proposed NASA Post 51-L baseline which consisted of FMEAs and 158 CIL items. Volume 1 contains the EPD and C subsystem description, analysis results, ground rules and assumptions, and some of the IOA worksheets.
NASA Technical Reports Server (NTRS)
Slaughter, B. C.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Main Propulsion System (MPS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to available data from the Rockwell Downey/NASA JSC FMEA/CIL review. The Orbiter MPS is composed of the Propellant Management Subsystem (PMS) consisting of the liquid oxygen (LO2) and liquid hydrogen (LH2) subsystems and the helium subsystem. The PMS is a system of manifolds, distribution lines, and valves by which the liquid propellants pass from the External Tank to the Space Shuttle Main Engine (SSME). The helium subsystem consists of a series of helium supply tanks and their associated regulators, control valves, and distribution lines. Volume 1 contains the MPS description, assessment results, ground rules and assumptions, and some of the IOA worksheets.
NASA Astrophysics Data System (ADS)
Djiokap, S. R. Tankio; Urgessa, Z. N.; Mbulanga, C. M.; Boumenou, C. Kameni; Venter, A.; Botha, J. R.
2018-04-01
In this paper, the growth of ZnO nanorods on bare and NiO-coated p-Si substrates is reported. A two-step chemical bath deposition process has been used to grow the nanorods. X-ray diffraction and scanning probe microscopy confirmed that the NiO films were polycrystalline, and that the average grain size correlated with the NiO layer thickness. The ZnO nanorod morphology, orientation and optical properties seemed to be unaffected by the intermediate NiO layer thickness. Current-voltage measurements confirmed the rectifying behavior of all the ZnO/NiO/Si heterostructures. The inclusion of a NiO layer between the substrate and the ZnO nanorods are shown to cause a reduction in both the forward and reverse bias currents. This is in qualitative agreement with the band diagram of these heterostructures, which suggests that the intermediate NiO layer should act as an electron blocking layer.
Sayed, Mohammed E; Porwal, Amit; Al-Faraj, Nida A; Bajonaid, Amal M; Sumayli, Hassan A
2017-07-01
Several techniques and methods have been proposed to estimate the anterior teeth dimensions in edentulous patients. However, this procedure remains challenging especially when preextraction records are not available. Therefore, the purpose of this study is to evaluate some of the existing extraoral and intraoral methods for estimation of anterior tooth dimensions and to propose a novel method for estimation of central incisor width (CIW) and length (CIL) for Saudi population. Extraoral and intraoral measurements were recorded for a total of 236 subjects. Descriptive statistical analysis and Pearson's correlation tests were performed. Association was evaluated between combined anterior teeth width (CATW) and interalar width (IAW), intercommisural width (ICoW) and interhamular notch distance (IHND) plus 10 mm. Evaluation of the linear relationship between central incisor length (CIL) with facial height (FH) and CIW with bizygomatic width (BZW) was also performed. Significant correlation was found between the CATW and ICoW and IAW (p-values <0.0001); however, no correlation was found relative to IHND plus 10 mm (p-value = 0.456). Further, no correlation was found between the FH and right CIL and BZW and right CIW (p-values = 0.255 and 0.822). The means of CIL, CIW, incisive papillae-fovea palatinae (IP-FP), and IHND were used to estimate the central incisor dimensions: CIL = FP-IP distance/4.45, CIW = IHND/4.49. It was concluded that the ICoW and IAW measurements are the only predictable methods to estimate the initial reference value for CATW. A proposed intraoral approach was hypothesized for estimation of CIW and CIL for the given population. Based on the results of the study, ICoW and IAW measurements can be useful in estimating the initial reference value for CATW, while the proposed novel approach using specific palatal dimensions can be used for estimating the width and length of central incisors. These methods are crucial to obtain esthetic treatment results within the parameters of the given population.
Recirculation of the Canary Current in Fall
NASA Astrophysics Data System (ADS)
Hernandez-Guerra, A.; Espino-Falcón, E.; Vélez-Belchí, P.; Pérez-Hernández, M. D.; Martínez, A.; Cana, L.
2015-12-01
CTD and LADCP data measured in October 2014 are used to describe water masses, geostrophic circulation and mass transport in the Eastern Boundary of the North Atlantic Subtropical Gyre. Initial geostrophic velocities are adjusted to velocities from the LADCP data to estimate an initial velocity at the reference layer. Final reference velocities and consequently circulation is estimated from an inverse box model applied to an ocean divided into 12 neutral density layers. This allows us to evaluate mass fluxes consistent with the thermal wind equation and mass conservation. Ekman transport derived from the Weather Research and Forecasting (WRF) model is added to the first layer and adjusted with the inverse model. The Canary Current (CC) transports southward a net mass of 3.8±0.7 Sv (1 Sv=106 m3/s≈109 kg/s) of North Atlantic Central Water (NACW) at the thermocline layers (~0-700 m) and 1.9±0.6 Sv of a mixture of Mediterranean Water (MW) and Antarctic Intermediate Water (AAIW) at intermediate layers (~800-1400 m). The CC recirculates northward at a rate of 4.8±0.8 Sv at the thermocline layers between the Lanzarote Island and the African coast (Lanzarote Passage) on this occasion. Separately, at intermediate layers, AAIW flows northward at a rate of 2.4±0.6 Sv through the Lanzarote Passage transported by the Intermediate Poleward Undercurrent (IPUC).
Method of making a ceramic with preferential oxygen reactive layer
NASA Technical Reports Server (NTRS)
Wang, Hongyu (Inventor); Luthra, Krishan Lal (Inventor)
2003-01-01
A method of forming an article. The method comprises forming a silicon-based substrate that is oxidizable by reaction with an oxidant to form at least one gaseous product and applying an intermediate layer/coating onto the substrate, wherein the intermediate layer/coating is oxidizable to a nongaseous product by reaction with the oxidant in preference to reaction of the silicon-containing substrate with the oxidant.
NASA Technical Reports Server (NTRS)
Dellacorte, Christopher; Pepper, Stephen V.; Honecy, Frank S.
1993-01-01
Outer layer of silver lubricates, while intermediate layer of titanium ensures adhesion. Lubricating outer films of silver deposited on thin intermediate films of titanium on alumina substrates found to reduce sliding friction and wear. Films provide effective lubrication for ceramic seals, bearings, and other hot sliding components in advanced high-temperature engines.
Sepúlveda, Nicasio
2002-01-01
A numerical model of the intermediate and Floridan aquifer systems in peninsular Florida was used to (1) test and refine the conceptual understanding of the regional ground-water flow system; (2) develop a data base to support subregional ground-water flow modeling; and (3) evaluate effects of projected 2020 ground-water withdrawals on ground-water levels. The four-layer model was based on the computer code MODFLOW-96, developed by the U.S. Geological Survey. The top layer consists of specified-head cells simulating the surficial aquifer system as a source-sink layer. The second layer simulates the intermediate aquifer system in southwest Florida and the intermediate confining unit where it is present. The third and fourth layers simulate the Upper and Lower Floridan aquifers, respectively. Steady-state ground-water flow conditions were approximated for time-averaged hydrologic conditions from August 1993 through July 1994 (1993-94). This period was selected based on data from Upper Floridan a quifer wells equipped with continuous water-level recorders. The grid used for the ground-water flow model was uniform and composed of square 5,000-foot cells, with 210 columns and 300 rows.
First report of Hibiscus infecting Cilevirus in Citrus sinensis in Meta and Casanare, Colombia
USDA-ARS?s Scientific Manuscript database
In February 2015, two sweet orange samples with severe citrus leprosis (CiL) symptoms were collected from Meta and Casanare states in Colombia and assayed for Cilevirus, Dichorhavirus and Higrevirus associated with CiL disease. PCR primers specific for CiLV-C2, but not primers specific for CiLV-C, C...
Buffer layers on metal alloy substrates for superconducting tapes
Jia, Quanxi; Foltyn, Stephen R.; Arendt, Paul N.; Groves, James R.
2004-10-05
An article including a substrate, at least one intermediate layer upon the surface of the substrate, a layer of an oriented cubic oxide material having a rock-salt-like structure upon the at least one intermediate layer, and a layer of a SrRuO.sub.3 buffer material upon the oriented cubic oxide material layer is provided together with additional layers such as a HTS top-layer of YBCO directly upon the layer of a SrRuO.sub.3 buffer material layer. With a HTS top-layer of YBCO upon at least one layer of the SrRuO.sub.3 buffer material in such an article, J.sub.c 's of up to 1.3.times.10.sup.6 A/cm.sup.2 have been demonstrated with projected I.sub.c 's of over 200 Amperes across a sample 1 cm wide.
Wang, Jianmei; Xia, Quanzhi; Ma, Yang; Meng, Fanning; Liang, Yinan; Li, Zhixiong
2017-09-25
To investigate the performance of bonding on the interface between ZChSnSb/Sn and steel body, the interfacial bonding energy on the interface of a ZChSnSb/Sn alloy layer and the steel body with or without Sn as an intermediate layer was calculated under the same loadcase using the molecular dynamics simulation software Materials Studio by ACCELRYS, and the interfacial bonding energy under different Babbitt thicknesses was compared. The results show that the bonding energy of the interface with Sn as an intermediate layer is 10% larger than that of the interface without a Sn layer. The interfacial bonding performances of Babbitt and the steel body with Sn as an intermediate layer are better than those of an interface without a Sn layer. When the thickness of the Babbitt layer of bushing is 17.143 Å, the interfacial bonding energy reaches the maximum, and the interfacial bonding performance is optimum. These findings illustrate the bonding mechanism of the interfacial structure from the molecular level so as to ensure the good bonding properties of the interface, which provides a reference for the improvement of the bush manufacturing process from the microscopic point of view.
High efficiency, low cost, thin film silicon solar cell design and method for making
Sopori, Bhushan L.
2001-01-01
A semiconductor device having a substrate, a conductive intermediate layer deposited onto said substrate, wherein the intermediate layer serves as a back electrode, an optical reflector, and an interface for impurity gettering, and a semiconductor layer deposited onto said intermediate layer, wherein the semiconductor layer has a grain size at least as large as the layer thickness, and preferably about ten times the layer thickness. The device is formed by depositing a metal layer on a substrate, depositing a semiconductive material on the metal-coated substrate to produce a composite structure, and then optically processing the composite structure by illuminating it with infrared electromagnetic radiation according to a unique time-energy profile that first produces pits in the backside surface of the semiconductor material, then produces a thin, highly reflective, low resistivity alloy layer over the entire area of the interface between the semiconductor material and the metal layer, and finally produces a grain-enhanced semiconductor layer. The time-energy profile includes increasing the energy to a first energy level to initiate pit formation and create the desired pit size and density, then ramping up to a second energy level in which the entire device is heated to produce an interfacial melt, and finally reducing the energy to a third energy level and holding for a period of time to allow enhancement in the grain size of the semiconductor layer.
High efficiency low cost thin film silicon solar cell design and method for making
Sopori, Bhushan L.
1999-01-01
A semiconductor device having a substrate, a conductive intermediate layer deposited onto said substrate, wherein the intermediate layer serves as a back electrode, an optical reflector, and an interface for impurity gettering, and a semiconductor layer deposited onto said intermediate layer, wherein the semiconductor layer has a grain size at least as large as the layer thickness, and preferably about ten times the layer thickness. The device is formed by depositing a metal layer on a substrate, depositing a semiconductive material on the metal-coated substrate to produce a composite structure, and then optically processing the composite structure by illuminating it with infrared electromagnetic radiation according to a unique time-energy profile that first produces pits in the backside surface of the semiconductor material, then produces a thin, highly reflective, low resistivity alloy layer over the entire area of the interface between the semiconductor material and the metal layer, and finally produces a grain-enhanced semiconductor layer. The time-energy profile includes increasing the energy to a first energy level to initiate pit formation and create the desired pit size and density, then ramping up to a second energy level in which the entire device is heated to produce an interfacial melt, and finally reducing the energy to a third energy level and holding for a period of time to allow enhancement in the grain size of the semiconductor layer.
Vaccination against a Virus-Encoded Cytokine Significantly Restricts Viral Challenge
Eberhardt, Meghan K.; Deshpande, Ashlesha; Chang, W. L. William; Barthold, Stephen W.
2013-01-01
Identification of immune correlates of protection for viral vaccines is complicated by multiple factors, but there is general consensus on the importance of antibodies that neutralize viral attachment to susceptible cells. Development of new viral vaccines has mostly followed this neutralizing antibody paradigm, but as a recent clinical trial of human cytomegalovirus (HCMV) vaccination demonstrated, this singular approach can yield limited protective efficacy. Since HCMV devotes >50% of its coding capacity to proteins that modulate host immunity, it is hypothesized that expansion of vaccine targets to include this part of the viral proteome will disrupt viral natural history. HCMV and rhesus cytomegalovirus (RhCMV) each encode an ortholog to the cellular interleukin-10 (cIL-10) cytokine: cmvIL-10 and rhcmvIL10, respectively. Despite extensive sequence divergence from their host's cIL-10, each viral IL-10 retains nearly identical functionality to cIL-10. Uninfected rhesus macaques were immunized with engineered, nonfunctional rhcmvIL-10 variants, which were constructed by site-directed mutagenesis to abolish binding to the cIL-10 receptor. Vaccinees developed antibodies that neutralized rhcmvIL-10 function with no cross-neutralization of cIL-10. Following subcutaneous RhCMV challenge, the vaccinees exhibited both reduced RhCMV replication locally at the inoculation site and systemically and significantly reduced RhCMV shedding in bodily fluids compared to controls. Attenuation of RhCMV infection by rhcmvIL-10 vaccination argues that neutralization of viral immunomodulation may be a new vaccine paradigm for HCMV by expanding potential vaccine targets. PMID:23946461
NASA Astrophysics Data System (ADS)
Zhu, Zheng; Fu, Liang; Sheng, D. N.
2017-10-01
We study the phase diagram of quantum Hall bilayer systems with total filing νT=1 /2 +1 /2 of the lowest Landau level as a function of layer distances d . Based on numerical exact diagonalization calculations, we obtain three distinct phases, including an exciton superfluid phase with spontaneous interlayer coherence at small d , a composite Fermi liquid at large d , and an intermediate phase for 1.1
Microsystem enabled photovoltaic modules and systems
Nielson, Gregory N; Sweatt, William C; Okandan, Murat
2015-05-12
A microsystem enabled photovoltaic (MEPV) module including: an absorber layer; a fixed optic layer coupled to the absorber layer; a translatable optic layer; a translation stage coupled between the fixed and translatable optic layers; and a motion processor electrically coupled to the translation stage to controls motion of the translatable optic layer relative to the fixed optic layer. The absorber layer includes an array of photovoltaic (PV) elements. The fixed optic layer includes an array of quasi-collimating (QC) micro-optical elements designed and arranged to couple incident radiation from an intermediate image formed by the translatable optic layer into one of the PV elements such that it is quasi-collimated. The translatable optic layer includes an array of focusing micro-optical elements corresponding to the QC micro-optical element array. Each focusing micro-optical element is designed to produce a quasi-telecentric intermediate image from substantially collimated radiation incident within a predetermined field of view.
NASA Astrophysics Data System (ADS)
Cho, Eunjoo; Oh, Ji Hye; Lee, Euna; Do, Young Rag; Kim, Eun Young
2016-11-01
Light at night disrupts the circadian clock and causes serious health problems in the modern world. Here, we show that newly developed four-package light-emitting diodes (LEDs) can provide harmless lighting at night. To quantify the effects of light on the circadian clock, we employed the concept of circadian illuminance (CIL). CIL represents the amount of light weighted toward the wavelengths to which the circadian clock is most sensitive, whereas visual illuminance (VIL) represents the total amount of visible light. Exposure to 12 h:12 h cycles of white LED light with high and low CIL values but a constant VIL value (conditions hereafter referred to as CH/CL) can entrain behavioral and molecular circadian rhythms in flies. Moreover, flies re-entrain to phase shift in the CH/CL cycle. Core-clock proteins are required for the rhythmic behaviors seen with this LED lighting scheme. Taken together, this study provides a guide for designing healthful white LED lights for use at night, and proposes the use of the CIL value for estimating the harmful effects of any light source on organismal health.
Kojima, Taisuke
2018-01-01
Molecular adsorption on a sensing surface involves molecule-substrate and molecule-molecule interactions. Combining optical systems and a quartz crystal microbalance (QCM) on the same sensing surface allows the quantification of such interactions and reveals the physicochemical properties of the adsorbed molecules. However, low sensitivity of the current reflection-based techniques compared to the QCM technique hinders the quantitative analysis of the adsorption events. Here, a layer-by-layer surface modification of a QCM sensor is studied to increase the optical sensitivity. The intermediate layers of organic-inorganic molecules and metal-metal oxide were explored on a gold (Au) surface of a QCM sensor. First, polyhedral oligomeric silsesquioxane-derivatives that served as the organic-inorganic intermediate layer were synthesized and modified on the Au-QCM surface. Meanwhile, titanium oxide, fabricated by anodic oxidation of titanium, was used as a metal-metal oxide intermediate layer on a titanium-coated QCM surface. The developed technique enabled interrogation of the molecular adsorption owing to the enhanced optical sensitivity.
Independent Orbiter Assessment (IOA): Assessment of the Orbiter Experiment (OEX) subsystem
NASA Technical Reports Server (NTRS)
Compton, J. M.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Orbiter Experiments (OEX) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. The results of that comparison for the Orbiter OEX hardware are documented. The IOA product for the OEX analysis consisted of 82 failure mode worksheets that resulted in two potential critical items being identified.
NASA Technical Reports Server (NTRS)
Schmeckpeper, K. R.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA first completed an analysis of the Electrical Power Distribution and Control (EPD and C) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EPD and C hardware. Volume 2 continues the presentation of IOA worksheets.
Korzekwa, David A.; Bingert, John F.; Peterson, Dean E.; Sheinberg, Haskell
1995-01-01
A superconductive article is made by inserting a rigid mandrel into an internal cavity of a first metallic tube, said tube having an interior surface and an exterior surface, said interior surface defining the interior cavity, forming a layer of a superconductive material or superconductive precursor upon the exterior surface of said first metallic tube, machining the layer of superconductive material or superconductive precursor to a predetermined diameter to form an intermediate article configured for insertion into a second metallic tube having an interior diameter corresponding to the predetermined diameter, inserting the machined intermediate article into a second metallic tube having an internal diameter corresponding to the predetermined diameter of the intermediate article to form a composite intermediate article, reducing or ironing the composite intermediate article to a predetermined cross-sectional diameter, and sintering the reduced or ironed composite intermediate article at temperatures and for time sufficient for the superconductive material or superconductive precursor to exhibit superconductivity.
Korzekwa, D.A.; Bingert, J.F.; Peterson, D.E.; Sheinberg, H.
1995-07-18
A superconductive article is made by inserting a rigid mandrel into an internal cavity of a first metallic tube, said tube having an interior surface and an exterior surface, said interior surface defining the interior cavity, forming a layer of a superconductive material or superconductive precursor upon the exterior surface of said first metallic tube, machining the layer of superconductive material or superconductive precursor to a predetermined diameter to form an intermediate article configured for insertion into a second metallic tube having an interior diameter corresponding to the predetermined diameter, inserting the machined intermediate article into a second metallic tube having an internal diameter corresponding to the predetermined diameter of the intermediate article to form a composite intermediate article, reducing or ironing the composite intermediate article to a predetermined cross-sectional diameter, and sintering the reduced or ironed composite intermediate article at temperatures and for time sufficient for the superconductive material or superconductive precursor to exhibit superconductivity. 2 figs.
Plume Splitting in a Two-layer Stratified Ambient Fluid
NASA Astrophysics Data System (ADS)
Ma, Yongxing; Flynn, Morris; Sutherland, Bruce
2017-11-01
A line-source plume descending into a two-layer stratified ambient fluid in a finite sized tank is studied experimentally. Although the total volume of ambient fluid is fixed, lower- and upper-layer fluids are respectively removed and added at a constant rate mimicking marine outfall through diffusers and natural and hybrid ventilated buildings. The influence of the plume on the ambient depends on the value of λ, defined as the ratio of the plume buoyancy to the buoyancy loss of the plume as it crosses the ambient interface. Similar to classical filling-box experiments, the plume can always reach the bottom of the tank if λ > 1 . By contrast, if λ < 1 , an intermediate layer eventually forms as a result of plume splitting. Eventually all of the plume fluid spreads within the intermediate layer. The starting time, tv, and the ending time, tt, of the transition process measured from experiments correlate with the value of λ. A three-layer ambient fluid is observed after transition, and the mean value of the measured densities of the intermediate layer fluid is well predicted using plume theory. Acknowledgments: Funding for this study was provided by NSERC.
Ceramic with preferential oxygen reactive layer
NASA Technical Reports Server (NTRS)
Wang, Hongyu (Inventor); Luthra, Krishan Lal (Inventor)
2001-01-01
An article comprises a silicon-containing substrate and an external environmental/thermal barrier coating. The external environmental/thermal barrier coating is permeable to diffusion of an environmental oxidant and the silicon-containing substrate is oxidizable by reaction with oxidant to form at least one gaseous product. The article comprises an intermediate layer/coating between the silicon-containing substrate and the environmental/thermal barrier coating that is oxidizable to a nongaseous product by reaction with the oxidant in preference to reaction of the silicon-containing substrate with the oxidant. A method of forming an article, comprises forming a silicon-based substrate that is oxidizable by reaction with oxidant to at least one gaseous product and applying an intermediate layer/coating onto the substrate, wherein the intermediate layer/coating is oxidizable to a nongaseous product by reaction with the oxidant in preference to reaction of the silicon-containing substrate with the oxidant.
A Metal Bump Bonding Method Using Ag Nanoparticles as Intermediate Layer
NASA Astrophysics Data System (ADS)
Fu, Weixin; Nimura, Masatsugu; Kasahara, Takashi; Mimatsu, Hayata; Okada, Akiko; Shoji, Shuichi; Ishizuka, Shugo; Mizuno, Jun
2015-11-01
The future development of low-temperature and low-pressure bonding technology is necessary for fine-pitch bump application. We propose a bump structure using Ag nanoparticles as an intermediate layer coated on a fine-pitch Cu pillar bump. The intermediate layer is prepared using an efficient and cost-saving squeegee-coating method followed by a 100°C baking process. This bump structure can be easily flattened before the bonding process, and the low-temperature sinterability of the nanoparticles is retained. The bonding experiment was successfully performed at 250°C and 39.8 MPa and the bonding strength was comparable to that achieved via other bonding technology utilizing metal particles or porous material as bump materials.
High efficiency low cost thin film silicon solar cell design and method for making
Sopori, B.L.
1999-04-27
A semiconductor device is described having a substrate, a conductive intermediate layer deposited onto said substrate, wherein the intermediate layer serves as a back electrode, an optical reflector, and an interface for impurity gettering, and a semiconductor layer deposited onto said intermediate layer, wherein the semiconductor layer has a grain size at least as large as the layer thickness, and preferably about ten times the layer thickness. The device is formed by depositing a metal layer on a substrate, depositing a semiconductive material on the metal-coated substrate to produce a composite structure, and then optically processing the composite structure by illuminating it with infrared electromagnetic radiation according to a unique time-energy profile that first produces pits in the backside surface of the semiconductor material, then produces a thin, highly reflective, low resistivity alloy layer over the entire area of the interface between the semiconductor material and the metal layer, and finally produces a grain-enhanced semiconductor layer. The time-energy profile includes increasing the energy to a first energy level to initiate pit formation and create the desired pit size and density, then ramping up to a second energy level in which the entire device is heated to produce an interfacial melt, and finally reducing the energy to a third energy level and holding for a period of time to allow enhancement in the grain size of the semiconductor layer. 9 figs.
Xia, Quanzhi; Ma, Yang; Meng, Fanning; Liang, Yinan; Li, Zhixiong
2017-01-01
To investigate the performance of bonding on the interface between ZChSnSb/Sn and steel body, the interfacial bonding energy on the interface of a ZChSnSb/Sn alloy layer and the steel body with or without Sn as an intermediate layer was calculated under the same loadcase using the molecular dynamics simulation software Materials Studio by ACCELRYS, and the interfacial bonding energy under different Babbitt thicknesses was compared. The results show that the bonding energy of the interface with Sn as an intermediate layer is 10% larger than that of the interface without a Sn layer. The interfacial bonding performances of Babbitt and the steel body with Sn as an intermediate layer are better than those of an interface without a Sn layer. When the thickness of the Babbitt layer of bushing is 17.143 Å, the interfacial bonding energy reaches the maximum, and the interfacial bonding performance is optimum. These findings illustrate the bonding mechanism of the interfacial structure from the molecular level so as to ensure the good bonding properties of the interface, which provides a reference for the improvement of the bush manufacturing process from the microscopic point of view. PMID:28946690
Marchant, David D.; Killpatrick, Don H.
1978-01-01
An electrode capable of withstanding high temperatures and suitable for use as a current collector in the channel of a magnetohydrodynamic (MHD) generator consists of a sintered powdered metal base portion, the upper surface of the base being coated with a first layer of nickel aluminide, an intermediate layer of a mixture of nickel aluminide - refractory ceramic on the first layer and a third or outer layer of a refractory ceramic material on the intermediate layer. The sintered powdered metal base resists spalling by the ceramic coatings and permits greater electrode compliance to thermal shock. The density of the powdered metal base can be varied to allow optimization of the thermal conductivity of the electrode and prevent excess heat loss from the channel.
Jia, Tao; Sun, Chen; Xu, Rongguo; Chen, Zhiming; Yin, Qingwu; Jin, Yaocheng; Yip, Hin-Lap; Huang, Fei; Cao, Yong
2017-10-18
A series of naphthalene diimide (NDI) based n-type conjugated polymers with amino-functionalized side groups and backbones were synthesized and used as cathode interlayers (CILs) in polymer and perovskite solar cells. Because of controllable amine side groups, all the resulting polymers exhibited distinct electronic properties such as oxidation potential of side chains, charge carrier mobilities, self-doping behaviors, and interfacial dipoles. The influences of the chemical variation of amine groups on the cathode interfacial effects were further investigated in both polymer and perovskite solar cells. We found that the decreased electron-donating property and enhanced steric hindrance of amine side groups substantially weaken the capacities of altering the work function of the cathode and trap passivation of the perovskite film, which induced ineffective interfacial modifications and declining device performance. Moreover, with further improvement of the backbone design through the incorporation of a rigid acetylene spacer, the resulting polymers substantially exhibited an enhanced electron-transporting property. Upon use as CILs, high power conversion efficiencies (PCEs) of 10.1% and 15.2% were, respectively, achieved in polymer and perovskite solar cells. Importantly, these newly developed n-type polymers were allowed to be processed over a broad thickness range of CILs in photovoltaic devices, and a prominent PCE of over 8% for polymer solar cells and 13.5% for perovskite solar cells can be achieved with the thick interlayers over 100 nm, which is beneficial for roll-to-roll coating processes. Our findings contribute toward a better understanding of the structure-performance relationship between CIL material design and solar cell performance, and provide important insights and guidelines for the design of high-performance n-type CIL materials for organic and perovskite optoelectronic devices.
Independent Orbiter Assessment (IOA): Assessment of the purge, vent and drain subsystem
NASA Technical Reports Server (NTRS)
Bynum, M. C., III
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Purge, Vent and Drain (PV and D) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter PV and D hardware. The PV and D Subsystem controls the environment of unpressurized compartments and window cavities, senses hazardous gases, and purges Orbiter/ET disconnect.
Independent Orbiter Assessment (IOA): Assessment of the orbital maneuvering subsystem, volume 2
NASA Technical Reports Server (NTRS)
Haufler, W. A.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Orbital Maneuvering System (OMS) hardware and electrical power distribution and control (EPD and C), generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter OMS hardware and EPD and C systems. Volume 2 continues the presentation of IOA worksheets and contains the critical items list and the NASA FMEA to IOA worksheet cross reference and recommendations.
Independent Orbiter Assessment (IOA): Assessment of the extravehicular mobility unit, volume 2
NASA Technical Reports Server (NTRS)
Raffaelli, Gary G.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort performed an independent analysis of the Extravehicular Mobility Unit (EMU) hardware and system, generating draft failure modes criticalities and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the most recent proposed Post 51-L NASA FMEA/CIL baseline. A resolution of each discrepancy from the comparison was provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EMU hardware. Volume 2 continues the presentation of IOA analysis worksheets and contains the potential critical items list and NASA FMEA to IOA worksheet cross references and recommendations.
Intermediate connector for stacked organic light emitting devices
D& #x27; Andrade, Brian
2013-02-12
A device is provided, having an anode, a cathode, and an intermediate connector disposed between the anode and the cathode. A first organic layer including an emissive sublayer is disposed between the anode and the intermediate connector, and a second including an emissive sublayer is disposed between the intermediate connector and the cathode. The intermediate connector includes a first metal having a work function lower than 4.0 eV and a second metal having a work function lower than 5.0 eV. The work function of the first metal is at least 0.5 eV less than the work function of the second metal. The first metal is in contact with a sublayer of the second organic layer that includes a material well adapted to receive holes from a low work function metal.
ERIC Educational Resources Information Center
Smith, Anita; Helms, Jenifer V.; St. John, Mark
2007-01-01
Inverness Research Associates served as external evaluators for the Center for Informal Learning and Schools (CILS) from its inception in 2002 as a National Science Foundation (NSF)-funded Center for Learning and Teaching. One of the programs that CILS developed was the Informal Learning Certificate (ILC) for informal science educators (mostly…
Yang, Yuzhao; Lin, Xiaofeng; Li, Wenlang; Ou, Jiemei; Yuan, Zhongke; Xie, Fangyan; Hong, Wei; Yu, Dingshan; Ma, Yuguang; Chi, Zhenguo; Chen, Xudong
2017-05-03
Cathode interlayers (CILs) with low-cost, low-toxicity, and excellent cathode modification ability are necessary for the large-scale industrialization of polymer solar cells (PSCs). In this contribution, we demonstrated one-pot synthesized carbon quantum dots (C-dots) with high production to serve as efficient CIL for inverted PSCs. The C-dots were synthesized by a facile, economical microwave pyrolysis in a household microwave oven within 7 min. Ultraviolet photoelectron spectroscopy (UPS) studies showed that the C-dots possessed the ability to form a dipole at the interface, resulting in the decrease of the work function (WF) of cathode. External quantum efficiency (EQE) measurements and 2D excitation-emission topographical maps revealed that the C-dots down-shifted the high energy near-ultraviolet light to low energy visible light to generate more photocurrent. Remarkably improvement of power conversion efficiency (PCE) was attained by incorporation of C-dots as CIL. The PCE was boosted up from 4.14% to 8.13% with C-dots as CIL, which is one of the best efficiency for i-PSCs used carbon based materials as interlayers. These results demonstrated that C-dots can be a potential candidate for future low cost and large area PSCs producing.
Structure for HTS composite conductors and the manufacture of same
Cotton, J.D.; Riley, G.N. Jr.
1999-06-01
A superconducting oxide composite structure including a superconducting oxide member, a metal layer surrounding the superconducting oxide member, and an insulating layer of a complex oxide formed in situ adjacent to the superconducting oxide member and the metal layer is provided together with a method of forming such a superconducting oxide composite structure including encapsulating a superconducting oxide member or precursor within a metal matrix layer from the group of: (1) a reactive metal sheath adjacent to the superconducting oxide member or precursor, the reactive metal sheath surrounded by a second metal layer or (2) an alloy containing a reactive metal; to form an intermediate product, and, heating the intermediate product at temperatures and for time sufficient to form an insulating layer of a complex oxide in situ, the insulating layer to the superconducting oxide member or precursor and the metal matrix layer. 10 figs.
Structure for hts composite conductors and the manufacture of same
Cotton, James D.; Riley, Jr., Gilbert Neal
1999-01-01
A superconducting oxide composite structure including a superconducting oxide member, a metal layer surrounding the superconducting oxide member, and an insulating layer of a complex oxide formed in situ adjacent to the superconducting oxide member and the metal layer is provided together with a method of forming such a superconducting oxide composite structure including encapsulating a superconducting oxide member or precursor within a metal matrix layer from the group of: (i) a reactive metal sheath adjacent to the superconducting oxide member or precursor, the reactive metal sheath surrounded by a second metal layer or (ii) an alloy containing a reactive metal; to form an intermediate product, and, heating the intermediate product at temperatures and for time sufficient to form an insulating layer of a complex oxide in situ, the insulating layer to the superconducting oxide member or precursor and the metal matrix layer.
Brandt, H.L.
1962-02-20
A process is given for decanning fuel elements that consist of a uranium core, an intermediate section either of bronze, silicon, Al-Si, and uranium silicide layers or of lead, Al-Si, and uranium silicide layers around said core, and an aluminum can bonded to said intermediate section. The aluminum can is dissolved in a solution of sodium hydroxide (9 to 20 wt%) and sodium nitrate (35 to 12 wt %), and the layers of the intermediate section are dissolved in a boiling sodium hydroxide solution of a minimum concentration of 50 wt%. (AEC) A method of selectively reducing plutonium oxides and the rare earth oxides but not uranium oxides is described which comprises placing the oxides in a molten solvent of zinc or cadmium and then adding metallic uranium as a reducing agent. (AEC)
Reflective coating for near-infrared immersion gratings
NASA Astrophysics Data System (ADS)
Kuzmenko, Paul J.; Ikeda, Yuji; Kobayashi, Naoto; Mirkarimi, Paul B.; Alameda, Jennifer B.
2012-09-01
Achieving high reflectivity from an immersed grating facet can be challenging in the near infrared. The reflectivity of metallic coatings in common use, such as Al and Cr/Au, decrease with decreasing wavelength in the near IR. A layer of copper on ZnSe or ZnS should have a high, immersed reflectivity based on tabulated values of refractive index, but in fact performs poorly. We attribute this to a chemical reaction between the copper and the selenium or sulfur. A non-reactive intermediate layer can prevent this problem. Since reflectivity at an interface increases with increasing difference in refractive index, it is beneficial to choose an intermediate layer of low index. A further improvement is gained by adjusting the layer thickness so that reflections from the two interfaces of the intermediate layer add constructively. We sputtered 130 nm of SiO2 onto ZnSe and ZnS substrates followed by 200 nm of Cu. The copper was then coated with 5 nm of SiC as a protective capping layer. Immersed reflectivity measured shortly after coating exceeded 95% between 1500 and 1100 nm and exceeded 90% down to 850 nm. A repeat measurement after long term exposure to high humidity conditions showed no changes.
NASA Technical Reports Server (NTRS)
Barickman, K.
1988-01-01
The McDonnell Douglas Astronautics Company (MDAC) was selected in June 1986 to perform an Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL). The IOA effort first completed an analysis of the Life Support and Airlock Support Systems (LSS and ALSS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. The discrepancies were flagged for potential future resolution. This report documents the results of that comparison for the Orbiter LSS and ALSS hardware. Volume 2 continues the presentation of IOA worksheets and contains the critical items list and NASA FMEA to IOA worksheet cross reference and recommendations.
Inter-Cellular Forces Orchestrate Contact Inhibition of Locomotion
Davis, John R.; Luchici, Andrei; Mosis, Fuad; Thackery, James; Salazar, Jesus A.; Mao, Yanlan; Dunn, Graham A.; Betz, Timo; Miodownik, Mark; Stramer, Brian M.
2015-01-01
Summary Contact inhibition of locomotion (CIL) is a multifaceted process that causes many cell types to repel each other upon collision. During development, this seemingly uncoordinated reaction is a critical driver of cellular dispersion within embryonic tissues. Here, we show that Drosophila hemocytes require a precisely orchestrated CIL response for their developmental dispersal. Hemocyte collision and subsequent repulsion involves a stereotyped sequence of kinematic stages that are modulated by global changes in cytoskeletal dynamics. Tracking actin retrograde flow within hemocytes in vivo reveals synchronous reorganization of colliding actin networks through engagement of an inter-cellular adhesion. This inter-cellular actin-clutch leads to a subsequent build-up in lamellar tension, triggering the development of a transient stress fiber, which orchestrates cellular repulsion. Our findings reveal that the physical coupling of the flowing actin networks during CIL acts as a mechanotransducer, allowing cells to haptically sense each other and coordinate their behaviors. PMID:25799385
NASA Technical Reports Server (NTRS)
Schmeckpeper, K. R.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA first completed an analysis of the Electrical Power Distribution and Control (EPD and C) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EPD and C hardware. Volume 3 continues the presentation of IOA worksheets and contains the potential critical items list and the NASA FMEA to IOA worksheet cross reference and recommendations.
An Independent Evaluation of the FMEA/CIL Hazard Analysis Alternative Study
NASA Technical Reports Server (NTRS)
Ray, Paul S.
1996-01-01
The present instruments of safety and reliability risk control for a majority of the National Aeronautics and Space Administration (NASA) programs/projects consist of Failure Mode and Effects Analysis (FMEA), Hazard Analysis (HA), Critical Items List (CIL), and Hazard Report (HR). This extensive analytical approach was introduced in the early 1970's and was implemented for the Space Shuttle Program by NHB 5300.4 (1D-2. Since the Challenger accident in 1986, the process has been expanded considerably and resulted in introduction of similar and/or duplicated activities in the safety/reliability risk analysis. A study initiated in 1995, to search for an alternative to the current FMEA/CIL Hazard Analysis methodology generated a proposed method on April 30, 1996. The objective of this Summer Faculty Study was to participate in and conduct an independent evaluation of the proposed alternative to simplify the present safety and reliability risk control procedure.
Large lattice mismatch effects on the epitaxial growth and magnetic properties of FePt films
NASA Astrophysics Data System (ADS)
Deng, Jinyu; Dong, Kaifeng; Yang, Ping; Peng, Yingguo; Ju, Ganping; Hu, Jiangfeng; Chow, Gan Moog; Chen, Jingsheng
2018-01-01
Heteroepitaxial film growth is crucial for magnetic and electronic devices. In this work, we reported the effects of the large lattice mismatch and film thickness on the epitaxial growth and magnetic properties of FePt films on ZrxTi1-xN (0 0 1) intermediate layer. FePt films with different thickness were deposited on ZrTiN intermediate layers with various doping concentration of TiN in ZrN. The increase in doping concentration of TiN caused a decrease in the lattice parameters of ZrTiN intermediate layer. It was found that (0 0 1) epitaxy of FePt 10 nm films was only achieved on ZrTiN intermediate layer when the TiN composition was ≥25 vol%, while (0 0 1) texture of 5 nm films was achieved on ZrTiN intermediate layer with a minimum of 50 vol% TiN composition. The in-plane lattice constants of FePt and Zr0.70Ti0.30N (25 vol% TiN) were 3.870 Å and 4.476 Å, respectively, which resulted in a lattice mismatch as large as 15.7%. These large lattice mismatch heterostructures adopted 7/6 domain matching epitaxy. The magneto-crystalline anisotropy of FePt films was improved with the increase in lattice mismatch. Intrinsic magnetic properties were extrapolated for FePt (30 nm)/Zr0.70Ti0.30N (30 nm)/TaN (30 nm)/MgO, and the Ms(0 K) and K1(0 K) were 1042 emu/cc and 5.10 × 107 erg/cc, respectively, which is comparable to that of bulk L10 FePt.
Park, Hyung Wook; Kim, Hong-Lim; Park, Yong Soo; Kim, In-Beom
2018-02-01
The retina is a highly specialised part of the brain responsible for visual processing. It is well-laminated; three layers containing five different types of neurons are compartmentalised by two synaptic layers. Among the retinal layers, the inner nuclear layer (INL) is composed of horizontal, bipolar, and amacrine cell types. Bipolar cells form one sublayer in the distal half of the IPL, while amacrine cells form another sublayer in the proximal half, without any border-like structure. Here, we report that a plexiform layer-like structure exists temporarily in the border between the bipolar and amacrine sublayers in the INL in the rat retina during retinal development. This transient intermediate plexiform layer (TIPL) appeared at postnatal day (PD) 7 and then disappeared around PD 12. Most apoptotic cells in the INL were found near the TIPL. These results suggest that the TIPL may contribute to the formation of sublayers and the cell number limit in the INL.
Fullerene surfactants and their use in polymer solar cells
Jen, Kwan-Yue; Yip, Hin-Lap; Li, Chang-Zhi
2015-12-15
Fullerene surfactant compounds useful as interfacial layer in polymer solar cells to enhance solar cell efficiency. Polymer solar cell including a fullerene surfactant-containing interfacial layer intermediate cathode and active layer.
Observations of the Ca/+/ twilight airglow from intermediate layers of ionization
NASA Technical Reports Server (NTRS)
Tepley, C. A.; Meriwether, J. W., Jr.; Walker, J. C. G.; Mathews, J. D.
1981-01-01
Optical and incoherent scatter radar techniques are applied to detect the presence of Ca(+) in lower thermospheric intermediate layers over Arecibo. The Arecibo 430 MHz radar is used to measure electron densities, and the altitude distribution and density of the calcium ion is inferred from the variation of twilight resonant scattering with solar depression angle. Ca(+) and electron column densities are compared, and results indicate that the composition of low-altitude intermediate layers is 2% Ca(+), which is consistent with rocket mass spectrometer measurements. Fe(+) and Mg(+) ultraviolet resonance lines are not detected from the ground due to ozone absorbing all radiation short of 3000 A, and measurements of the neutral iron resonance line at 3860 A show that an atmospheric continuum may result in overestimations of emission rates at high solar depression angles.
NASA Astrophysics Data System (ADS)
Takeuchi, Kai; Fujino, Masahisa; Matsumoto, Yoshiie; Suga, Tadatomo
2018-02-01
The temporary bonding of polyimide (PI) films and glass substrates is a key technology for realizing flexible devices with thin-film transistors (TFTs). In this paper, we report the surface activated bonding (SAB) method using Si intermediate layers and its bonding and debonding mechanisms after heating. The bonding interface composed of Si and Fe shows a higher bond strength than the interface of only Si, while the bond strengths of both interfaces decrease with post bonding heating. It is also clarified by composition analysis on the debonded surfaces and cross-sectional observation of the bonding interface that the bond strength depends on the toughness of the intermediated layers and PI. The SAB method using Si intermediate layers is found to be applicable to the bonding and debonding of PI and glass.
Independent Orbiter Assessment (IOA): Assessment of the mechanical actuation subsystem, volume 2
NASA Technical Reports Server (NTRS)
Bradway, M. W.; Slaughter, W. T.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine draft failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline that was available. A resolution of each discrepancy from the comparison was provided through additional analysis as required. These discrepancies were flagged as issues, and recommendations were made based on the FMEA data available at the time. This report documents the results of that comparison for the Orbiter Mechanical Actuation System (MAS) hardware. Specifically, the MAS hardware consists of the following components: Air Data Probe (ADP); Elevon Seal Panel (ESP); External Tank Umbilical (ETU); Ku-Band Deploy (KBD); Payload Bay Doors (PBD); Payload Bay Radiators (PBR); Personnel Hatches (PH); Vent Door Mechanism (VDM); and Startracker Door Mechanism (SDM). Criticality was assigned based upon the severity of the effect for each failure mode. Volume 2 continues the presentation of IOA analysis worksheets and contains the potential critical items list, detailed analysis, and NASA FMEA/CIL to IOA worksheet cross reference and recommendations.
Substrate structures for InP-based devices
Wanlass, Mark W.; Sheldon, Peter
1990-01-01
A substrate structure for an InP-based semiconductor device having an InP based film is disclosed. The substrate structure includes a substrate region having a lightweight bulk substrate and an upper GaAs layer. An interconnecting region is disposed between the substrate region and the InP-based device. The interconnecting region includes a compositionally graded intermediate layer substantially lattice-matched at one end to the GaAs layer and substantially lattice-matched at the opposite end to the InP-based film. The interconnecting region further includes a dislocation mechanism disposed between the GaAs layer and the InP-based film in cooperation with the graded intermediate layer, the buffer mechanism blocking and inhibiting propagation of threading dislocations between the substrate region, and the InP-based device.
Fiber laser welding of austenitic steel and commercially pure copper butt joint
NASA Astrophysics Data System (ADS)
Kuryntsev, S. V.; Morushkin, A. E.; Gilmutdinov, A. Kh.
2017-03-01
The fiber laser welding of austenitic stainless steel and commercially pure copper in butt joint configuration without filler or intermediate material is presented. In order to melt stainless steel directly and melt copper via heat conduction a defocused laser beam was used with an offset to stainless steel. During mechanical tests the weld seam was more durable than heat affected zone of copper so samples without defects could be obtained. Three process variants of offset of the laser beam were applied. The following tests were conducted: tensile test of weldment, intermediate layer microhardness, optical metallography, study of the chemical composition of the intermediate layer, fractography. Measurements of electrical resistivity coefficients of stainless steel, copper and copper-stainless steel weldment were made, which can be interpreted or recalculated as the thermal conductivity coefficient. It shows that electrical resistivity coefficient of cooper-stainless steel weldment higher than that of stainless steel. The width of intermediate layer between stainless steel and commercially pure copper was 41-53 μm, microhardness was 128-170 HV0.01.
Improved ohmic contact of Ga-Doped ZnO to p-GaN by using copper sulfide intermediate layers
NASA Astrophysics Data System (ADS)
Gu, Wen; Xu, Tao; Zhang, Jianhua
2013-11-01
Copper sulfide (CuS) was used as the intermediate layer to build ohmic contact of Ga-Doped ZnO (GZO) transparent conduction layer (TCL) to p-GaN. The CuS and GZO layers were prepared by thermal evaporation and RF magnetron sputtering, respectively. Although the GZO-only contacts to p-GaN exhibit nonlinear behavior, ohmic contact with a specific contact resistance of 1.6 × 10-2 Ω cm2 has been realized by inserting 3 nm CuS layer between GZO and p-GaN. The optical transmittance of CuS/GZO film was measured to be higher than 80% in the range of 450-600 nm wavelength. The possible mechanism for the ohmic contact behavior can be attributed to the increased hole concentration of p-GaN surface induced by CuS films after annealing. The forward voltage of LEDs with CuS/GZO TCL has been reduced by 1.7 V at 20 mA and the output power has been increased by 29.6% at 100 mA compared with LEDs without CuS interlayer. These results indicated that using CuS intermediate layer could be a potential ohmic contact method to realize high-efficiency LEDs.
NASA Astrophysics Data System (ADS)
Sallée, J.-B.; Shuckburgh, E.; Bruneau, N.; Meijers, A. J. S.; Bracegirdle, T. J.; Wang, Z.; Roy, T.
2013-04-01
The ability of the models contributing to the fifth Coupled Models Intercomparison Project (CMIP5) to represent the Southern Ocean hydrological properties and its overturning is investigated in a water mass framework. Models have a consistent warm and light bias spread over the entire water column. The greatest bias occurs in the ventilated layers, which are volumetrically dominated by mode and intermediate layers. The ventilated layers have been observed to have a strong fingerprint of climate change and to impact climate by sequestrating a significant amount of heat and carbon dioxide. The mode water layer is poorly represented in the models and both mode and intermediate water have a significant fresh bias. Under increased radiative forcing, models simulate a warming and lightening of the entire water column, which is again greatest in the ventilated layers, highlighting the importance of these layers for propagating the climate signal into the deep ocean. While the intensity of the water mass overturning is relatively consistent between models, when compared to observation-based reconstructions, they exhibit a slightly larger rate of overturning at shallow to intermediate depths, and a slower rate of overturning deeper in the water column. Under increased radiative forcing, atmospheric fluxes increase the rate of simulated upper cell overturning, but this increase is counterbalanced by diapycnal fluxes, including mixed-layer horizontal mixing, and mostly vanishes.
Davis, J.H.
1998-01-01
The Naval Air Station, Jacksonville (herein referred to as the Station), occupies 3,800 acres adjacent to the St. Johns River in Duval County, Florida. Operable Unit 3 (OU3) occupies 134 acres on the eastern side of the Station and has been used for industrial and commercial purposes since World War II. Ground water contaminated by chlorinated organic compounds has been detected in the surficial aquifer at OU3. The U.S. Navy and U.S. Geological Survey (USGS) conducted a cooperative hydrologic study to evaluate the potential for ground water discharge to the neighboring St. Johns River. A ground-water flow model, previously developed for the area, was recalibrated for use in this study. At the Station, the surficial aquifer is exposed at land surface and forms the uppermost permeable unit. The aquifer ranges in thickness from 30 to 100 feet and consists of unconsolidated silty sands interbedded with local beds of clay. The low-permeability clays of the Hawthorn Group form the base of the aquifer. The USGS previously conducted a ground-water investigation at the Station that included the development and calibration of a 1-layer regional ground-water flow model. For this investigation, the regional model was recalibrated using additional data collected after the original calibration. The recalibrated model was then used to establish the boundaries for a smaller subregional model roughly centered on OU3. Within the subregional model, the surficial aquifer is composed of distinct upper and intermediate layers. The upper layer extends from land surface to a depth of approximately 15 feet below sea level; the intermediate layer extends from the upper layer down to the top of the Hawthorn Group. In the northern and central parts of OU3, the upper and intermediate layers are separated by a low-permeability clay layer. Horizontal hydraulic conductivities in the upper layer, determined from aquifer tests, range from 0.19 to 3.8 feet per day. The horizontal hydraulic conductivity in the intermediate layer, determined from one aquifer test, is 20 feet per day. An extensive stormwater drainage system is present at OU3 and the surrounding area. Some of the stormwater drains have been documented to be draining ground water from the upper layer of the surficial aquifer, whereas other drains are only suspected to be draining ground water. The subregional model contained 78 rows and 148 columns of square model cells that were 100 feet on each side. Vertically, the surficial aquifer was divided into two layers; layer 1 represented the upper layer and layer 2 represented the intermediate layer. Steady-state ground-water flow conditions were assumed. The model was calibrated to head data collected on October 29 and 30, 1996. After calibration, the model matched all 67 measured heads to within the calibration criterion of 1 foot; and 48 of 67 simulated heads (72 percent) were within 0.5 foot. Model simulated recharge rates ranged from 0.4 inch per year in areas that were largely paved to 13.0 inches per year in irrigated areas. Simulated hydraulic conductivities in the upper layer at OU3 ranged from 0.5 foot per day in the north to 1.0 foot per day in the south. Simulated vertical leakance between the upper and intermediate layers ranged from 1.0x10-6 per day in an area with low-permeability clays to 4.3x10-2 per day in an area that had been dredged. Simulated transmissivities in the intermediate layer ranged from 25 feet squared per day in an area of low-permeability channel-fill deposits to a high of 1,200 feet squared per day in areas covering most of OU3. Simulated riverbed conductances ranged from 4 to 60 feet squared per day and simulated bottom conductances of leaking stormwater drains ranged from 5 to 20 feet squared per day. The direction and velocity of ground-water flow was determined using particle-tracking techniques. Ground-water flow in the upper layer was generally eastward toward the St. Johns River. However, leaking stormwat
Zong, Chuanyong; Zhao, Yan; Ji, Haipeng; Xie, Jixun; Han, Xue; Wang, Juanjuan; Cao, Yanping; Lu, Conghua; Li, Hongfei; Jiang, Shichun
2016-08-01
Here, a simple combined strategy of surface wrinkling with visible light irradiation to fabricate well tunable hierarchical surface patterns on azo-containing multilayer films is reported. The key to tailor surface patterns is to introduce a photosensitive poly(disperse orange 3) intermediate layer into the film/substrate wrinkling system, in which the modulus decrease is induced by the reversible photoisomerization. The existence of a photoinert top layer prevents the photoisomerization-induced stress release in the intermediate layer to some extent. Consequently, the as-formed wrinkling patterns can be modulated over a large area by light irradiation. Interestingly, in the case of selective exposure, the wrinkle wavelength in the exposed region decreases, while the wrinkles in the unexposed region are evolved into highly oriented wrinkles with the orientation perpendicular to the exposed/unexposed boundary. Compared with traditional single layer-based film/substrate systems, the multilayer system consisting of the photosensitive intermediate layer offers unprecedented advantages in the patterning controllability/universality. As demonstrated here, this simple and versatile strategy can be conveniently extended to functional multilayer systems for the creation of prescribed hierarchical surface patterns with optically tailored microstructures. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Li, Panyuan; Wang, Zhi; Li, Wen; Liu, Yanni; Wang, Jixiao; Wang, Shichang
2015-07-22
It is desirable to develop high-performance composite membranes for efficient CO2 separation in CO2 capture process. Introduction of a highly permeable polydimethylsiloxane (PDMS) intermediate layer between a selective layer and a porous support has been considered as a simple but efficient way to enhance gas permeance while maintaining high gas selectivity, because the introduced intermediate layer could benefit the formation of an ultrathin defect-free selective layer owing to the circumvention of pore penetration phenomenon. However, the selection of selective layer materials is unfavorably restricted because of the low surface energy of PDMS. Various highly hydrophilic membrane materials such as amino group-rich polyvinylamine (PVAm), a representative facilitated transport membrane material for CO2 separation, could not be facilely coated over the surface of the hydrophobic PDMS intermediate layer uniformly. Inspired by the hydrophilic nature and strong adhesive ability of polydopamine (PDA), PDA was therefore selected as a versatile molecular bridge between hydrophobic PDMS and hydrophilic PVAm. The PDA coating endows a highly compatible interface between both components with a large surface energy difference via multiple-site cooperative interactions. The resulting multilayer composite membrane with a thin facilitated transport PVAm selective layer exhibits a notably enhanced CO2 permeance (1887 GPU) combined with a slightly improved CO2/N2 selectivity (83), as well as superior structural stability. Similarly, the multilayer composite membrane with a hydrophilic CO2-philic Pebax 1657 selective layer was also developed for enhanced CO2 separation performance.
Intermediate-band photosensitive device with quantum dots embedded in energy fence barrier
Forrest, Stephen R.; Wei, Guodan
2010-07-06
A plurality of layers of a first semiconductor material and a plurality of dots-in-a-fence barriers disposed in a stack between a first electrode and a second electrode. Each dots-in-a-fence barrier consists essentially of a plurality of quantum dots of a second semiconductor material embedded between and in direct contact with two layers of a third semiconductor material. Wave functions of the quantum dots overlap as at least one intermediate band. The layers of the third semiconductor material are arranged as tunneling barriers to require a first electron and/or a first hole in a layer of the first material to perform quantum mechanical tunneling to reach the second material within a respective quantum dot, and to require a second electron and/or a second hole in a layer of the first semiconductor material to perform quantum mechanical tunneling to reach another layer of the first semiconductor material.
Combined PDF and Rietveld studies of ADORable zeolites and the disordered intermediate IPC-1P.
Morris, Samuel A; Wheatley, Paul S; Položij, Miroslav; Nachtigall, Petr; Eliášová, Pavla; Čejka, Jiří; Lucas, Tim C; Hriljac, Joseph A; Pinar, Ana B; Morris, Russell E
2016-09-28
The disordered intermediate of the ADORable zeolite UTL has been structurally confirmed using the pair distribution function (PDF) technique. The intermediate, IPC-1P, is a disordered layered compound formed by the hydrolysis of UTL in 0.1 M hydrochloric acid solution. Its structure is unsolvable by traditional X-ray diffraction techniques. The PDF technique was first benchmarked against high-quality synchrotron Rietveld refinements of IPC-2 (OKO) and IPC-4 (PCR) - two end products of IPC-1P condensation that share very similar structural features. An IPC-1P starting model derived from density functional theory was used for the PDF refinement, which yielded a final fit of Rw = 18% and a geometrically reasonable structure. This confirms the layers do stay intact throughout the ADOR process and shows PDF is a viable technique for layered zeolite structure determination.
Composite hydrogen separation element and module
Edlund, D.J.
1996-03-12
There are disclosed improvements in multicomponent composite metal membranes useful for the separation of hydrogen, the improvements comprising the provision of a flexible porous intermediate layer between a support layer and a nonporous hydrogen-permeable coating metal layer, and the provision of a textured coating metal layer. 15 figs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Kang Min; Kim, Yeon Sung; Yang, Hae Woong
2015-01-15
An investigation of the coating structure formed on Mg–3 wt.%Al–1 wt.%Zn alloy sample subjected to plasma electrolytic oxidation was examined by field-emission transmission electron microscopy. The plasma electrolytic oxidation process was conducted in a phosphoric acid electrolyte containing K{sub 2}ZrF{sub 6} for 600 s. Microstructural observations showed that the coating consisting of MgO, MgF{sub 2}, and ZrO{sub 2} phases was divided into three distinctive parts, the barrier, intermediate, and outer layers. Nanocrystalline MgO and MgF{sub 2} compounds were observed mainly in the barrier layer of ~ 1 μm thick near to the substrate. From the intermediate to outer layers, variousmore » ZrO{sub 2} polymorphs appeared due to the effects of the plasma arcing temperature on the phase transition of ZrO{sub 2} compounds during the plasma electrolytic oxidation process. In the outer layer, MgO compound grew in the form of a dendrite-like structure surrounded by cubic ZrO{sub 2}. - Highlights: • The barrier layer containing MgO and MgF{sub 2} was observed near to the Mg substrate. • In the intermediate layer, m-, t-, and o-ZrO{sub 2} compounds were additionally detected. • The outer layer contained MgO with the dendrite-like structure surrounded by c-ZrO{sub 2}. • The grain sizes of compounds in oxide layer increased from barrier to outer layer.« less
A boron and gallium co-doped ZnO intermediate layer for ZnO/Si heterojunction diodes
NASA Astrophysics Data System (ADS)
Lu, Yuanxi; Huang, Jian; Li, Bing; Tang, Ke; Ma, Yuncheng; Cao, Meng; Wang, Lin; Wang, Linjun
2018-01-01
ZnO (Zinc oxide)/Si (Silicon) heterojunctions were prepared by depositing n-type ZnO films on p-type single crystal Si substrates using magnetron sputtering. A boron and gallium co-doped ZnO (BGZO) high conductivity intermediate layer was deposited between aurum (Au) electrodes and ZnO films. The influence of the BGZO layer on the properties of Au/ZnO contacts and the performance of ZnO/Si heterojunctions was investigated. The results show an improvement in contact resistance by introducing the BGZO layer. Compared with the ZnO/Si heterojunction, the BGZO/ZnO/Si heterojunction exhibits a larger forward current, a smaller turn-on voltage and higher ratio of ultraviolet (UV) photo current/dark current.
Method of manufacturing a matrix for the detection of mismatches
Ershov, Gennady Moiseevich; Mirzabekov, Andrei Darievich
1998-01-01
This method for preparing micromatrices consists in applying a specially-patterned intermediate layer of laser-absorbing substance on a solid support. The configuration of the sublayer fully corresponds to the topology of the manufactured matrix. The intermediate layer is further covered by a continuous layer of gel , the gel and the material of the support being transparent towards laser radiation. The gel layer is irradiated by a laser beam for a time needed to evaporate simultaneously the gel in the places immediately above the laser-absorbing sublayer and the sublayer itself. Oligonucleotides from a chosen set are then attached to the formed gel `cells`, one oligonucleotide to each cell. This method is intended for use in biotechnology, specifically for deciphering the nucleotide sequence of DNA.
Defect-enhanced performance of a 3D graphene anode in a lithium-ion battery
NASA Astrophysics Data System (ADS)
Guo, Hongchen; Long, Deng; Zheng, Zongmin; Chen, Xinyi; Ng, Alan M. C.; Lu, Miao
2017-12-01
Morphological defects were generated in an undoped 3D graphene structure via the involvement of a ZnO and Mg(OH)2 intermediate nanostructure layer placed between two layers of vapor-deposited graphene. Once the intermediate layer was etched, the 3D graphene lost support and shrank; during this process many morphological defects were formed. The electrochemical performance of the derived defective graphene utilized as the anode of a lithium (Li)-ion battery was significantly improved from ˜382 mAh g-1 to ˜2204 mAh g-1 at 0.5 A g-1 compared to normal 3D graphene. The derived defective graphene exhibited an initial capacity of 1009 mAh g-1 and retention of 83% at 4 A g-1 for 500 cycles, and ˜330 mAh g-1 at a high rate of 20 A g-1. Complicated defects such as wrinkles, pores, and particles formed during the etching of the intermediate layer, were considered to contribute to the improvement of the electrochemical performance.
Neural Network Model For Fast Learning And Retrieval
NASA Astrophysics Data System (ADS)
Arsenault, Henri H.; Macukow, Bohdan
1989-05-01
An approach to learning in a multilayer neural network is presented. The proposed network learns by creating interconnections between the input layer and the intermediate layer. In one of the new storage prescriptions proposed, interconnections are excitatory (positive) only and the weights depend on the stored patterns. In the intermediate layer each mother cell is responsible for one stored pattern. Mutually interconnected neurons in the intermediate layer perform a winner-take-all operation, taking into account correlations between stored vectors. The performance of networks using this interconnection prescription is compared with two previously proposed schemes, one using inhibitory connections at the output and one using all-or-nothing interconnections. The network can be used as a content-addressable memory or as a symbolic substitution system that yields an arbitrarily defined output for any input. The training of a model to perform Boolean logical operations is also described. Computer simulations using the network as an autoassociative content-addressable memory show the model to be efficient. Content-addressable associative memories and neural logic modules can be combined to perform logic operations on highly corrupted data.
Inter-cellular forces orchestrate contact inhibition of locomotion.
Davis, John R; Luchici, Andrei; Mosis, Fuad; Thackery, James; Salazar, Jesus A; Mao, Yanlan; Dunn, Graham A; Betz, Timo; Miodownik, Mark; Stramer, Brian M
2015-04-09
Contact inhibition of locomotion (CIL) is a multifaceted process that causes many cell types to repel each other upon collision. During development, this seemingly uncoordinated reaction is a critical driver of cellular dispersion within embryonic tissues. Here, we show that Drosophila hemocytes require a precisely orchestrated CIL response for their developmental dispersal. Hemocyte collision and subsequent repulsion involves a stereotyped sequence of kinematic stages that are modulated by global changes in cytoskeletal dynamics. Tracking actin retrograde flow within hemocytes in vivo reveals synchronous reorganization of colliding actin networks through engagement of an inter-cellular adhesion. This inter-cellular actin-clutch leads to a subsequent build-up in lamellar tension, triggering the development of a transient stress fiber, which orchestrates cellular repulsion. Our findings reveal that the physical coupling of the flowing actin networks during CIL acts as a mechanotransducer, allowing cells to haptically sense each other and coordinate their behaviors. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
Enantioseparation by Capillary Electrophoresis Using Ionic Liquids as Chiral Selectors.
Greño, Maider; Marina, María Luisa; Castro-Puyana, María
2018-11-02
Capillary electrophoresis (CE) is one of the most widely employed analytical techniques to achieve enantiomeric separations. In spite of the fact that there are many chiral selectors commercially available to perform enantioseparations by CE, one of the most relevant topics in this field is the search for new selectors capable of providing high enantiomeric resolutions. Chiral ionic liquids (CILs) have interesting characteristics conferring them a high potential in chiral separations although only some of them are commercially available. The aim of this article is to review all the works published on the use of CILs as chiral selectors in the development of enantioselective methodologies by CE, covering the period from 2006 (when the first research work on this topic was published) to 2017. The use of CILs as sole chiral selectors, as chiral selectors in dual systems or as chiral ligands will be considered. This review also provides detailed analytical information on the experimental conditions used to carry out enantioseparations in different fields as well as on the separation mechanism involved.
1994-03-01
4 en cn aqr . IV qt go 4m Ln co co id rý w It 01)(0 111 Ln cacao 11 cj 4 MW MV." 11 1 ca 0 CD (D C4 cn v (D -4 4 In to U) to W) m (D cn (D -4 w...CY (m C-i In = Go 0 1 90000 11 CL q1t w CI I% cL In CL CL INA CL CL 0) CL W CIL CIL In V CIL ý4 en 11 1 cacao 11 47) 1w In 0) 11 0 1 CIO 0 co If...U)--0)O4 ON ON 3 11 a CONO IICONC 0 00 U> N 0-4 cc- (nWO De u 0 00 ;m -00 F- 00 L 00 .-11J ORICON BI K I0 (1 ý u z a ) 0-00 a- L 0 1 ɘ 10 0.w qt4
NASA Astrophysics Data System (ADS)
Chong, Haining; Wang, Zhewei; Chen, Chaonan; Xu, Zemin; Wu, Ke; Wu, Lan; Xu, Bo; Ye, Hui
2018-04-01
In order to suppress dislocation generation, we develop a "three-step growth" method to heteroepitaxy low dislocation density germanium (Ge) layers on silicon with the MBE process. The method is composed of 3 growth steps: low temperature (LT) seed layer, LT-HT intermediate layer as well as high temperature (HT) epilayer, successively. Threading dislocation density (TDD) of epitaxial Ge layers is measured as low as 1.4 × 106 cm-2 by optimizing the growth parameters. The results of Raman spectrum showed that the internal strain of heteroepitaxial Ge layers is tensile and homogeneous. During the growth of LT-HT intermediate layer, TDD reduction can be obtained by lowering the temperature ramping rate, and high rate deposition maintains smooth surface morphology in Ge epilayer. A mechanism based on thermodynamics is used to explain the TDD and surface morphological dependence on temperature ramping rate and deposition rate. Furthermore, we demonstrate that the Ge layer obtained can provide an excellent platform for III-V materials integrated on Si.
Accident resistant transport container
Andersen, John A.; Cole, James K.
1980-01-01
The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.
Accident resistant transport container
Anderson, J.A.; Cole, K.K.
The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.
Gradient SiNO anti-reflective layers in solar selective coatings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ren, Zhifeng; Cao, Feng; Sun, Tianyi
A solar selective coating includes a substrate, a cermet layer having nanoparticles therein deposited on the substrate, and an anti-reflection layer deposited on the cermet layer. The cermet layer and the anti-reflection layer may each be formed of intermediate layers. A method for constructing a solar-selective coating is disclosed and includes preparing a substrate, depositing a cermet layer on the substrate, and depositing an anti-reflection layer on the cermet layer.
Cadherin-11 Mediates Contact Inhibition of Locomotion during Xenopus Neural Crest Cell Migration
Becker, Sarah F. S.; Mayor, Roberto; Kashef, Jubin
2013-01-01
Collective cell migration is an essential feature both in embryonic development and cancer progression. The molecular mechanisms of these coordinated directional cell movements still need to be elucidated. The migration of cranial neural crest (CNC) cells during embryogenesis is an excellent model for collective cell migration in vivo. These highly motile and multipotent cells migrate directionally on defined routes throughout the embryo. Interestingly, local cell-cell interactions seem to be the key force for directionality. CNC cells can change their migration direction by a repulsive cell response called contact inhibition of locomotion (CIL). Cell protrusions collapse upon homotypic cell-cell contact and internal repolarization leads to formation of new protrusions toward cell-free regions. Wnt/PCP signaling was shown to mediate activation of small RhoGTPase RhoA and inhibition of cell protrusions at the contact side. However, the mechanism how a cell recognizes the contact is poorly understood. Here, we demonstrate that Xenopus cadherin-11 (Xcad-11) mediated cell-cell adhesion is necessary in CIL for directional and collective migration of CNC cells. Reduction of Xcad-11 adhesive function resulted in higher invasiveness of CNC due to loss of CIL. Additionally, transplantation analyses revealed that CNC migratory behaviour in vivo is non-directional and incomplete when Xcad-11 adhesive function is impaired. Blocking Wnt/PCP signaling led to similar results underlining the importance of Xcad-11 in the mechanism of CIL and directional migration of CNC. PMID:24392028
Surface control alloy substrates and methods of manufacture therefor
Fritzemeier, Leslie G.; Li, Qi; Rupich, Martin W.; Thompson, Elliott D.; Siegal, Edward J.; Thieme, Cornelis Leo Hans; Annavarapu, Suresh; Arendt, Paul N.; Foltyn, Stephen R.
2004-05-04
Methods and articles for controlling the surface of an alloy substrate for deposition of an epitaxial layer. The invention includes the use of an intermediate layer to stabilize the substrate surface against oxidation for subsequent deposition of an epitaxial layer.
NASA Astrophysics Data System (ADS)
Park, Donghyun; Shin, Soo Jin; Oh, Tae Sung
2018-01-01
Thin Au films with thickness of 150 nm could be reversibly stretched up to 30% elongation on polydimethylsiloxane (PDMS) substrate with 150-nm-thick Parylene C deposited as intermediate layer instead of a Cr adhesion layer. Prestretching of the Parylene-deposited PDMS was effective to suppress the resistance increase of Au films during their tensile elongation. While the resistance change rate Δ R/ R 0 of the Au film at 30% elongation was 11 without prestretching of the Parylene-deposited PDMS, it was substantially suppressed to 0.4 with 30% prestretching of the Parylene-deposited PDMS.
Hinklin, Thomas Ray; Lewinsohn, Charles Arthur
2015-06-30
A module for separating oxygen from an oxygen-containing gaseous mixture comprising planar solid-state membrane units, each membrane unit comprising planar dense mixed conducting oxides layers, planar channel-free porous support layers, and one or more planar intermediate support layers comprising at least one channeled porous support layer. The porosity of the planar channeled porous support layers is less than the porosity of the planar channel-free porous support layers.
Zhou, Yong-Ning; Yue, Ji-Li; Hu, Enyuan; ...
2016-08-08
Using fast time-resolved in situ X-ray diffraction, charge-rate dependent phase transition processes of layer structured cathode material LiNi 1/3Mn 1/3Co 1/3O 2 for lithium-ion batteries are studied. During first charge, intermediate phases emerge at high rates of 10C, 30C, and 60C, but not at low rates of 0.1C and 1C. These intermediate phases can be continuously observed during relaxation after the charging current is switched off. After half-way charging at high rate, sample studied by scanning transmission electron microscopy shows Li-rich and Li-poor phases' coexistence with tetrahedral occupation of Li in Li-poor phase. Also, the high rate induced overpotential ismore » thought to be the driving force for the formation of this intermediate Li-poor phase. The in situ quick X-ray absorption results show that the oxidation of Ni accelerates with increasing charging rate and the Ni 4+ state can be reached at the end of charge with 30C rate. Finally, these results give new insights in the understanding of the layered cathodes during high-rate charging.« less
Strain-tolerant ceramic coated seal
Schienle, James L.; Strangman, Thomas E.
1994-01-01
A metallic regenerator seal is provided having multi-layer coating comprising a NiCrAlY bond layer, a yttria stabilized zirconia (YSZ) intermediate layer, and a ceramic high temperature solid lubricant surface layer comprising zinc oxide, calcium fluoride, and tin oxide. An array of discontinuous grooves is laser machined into the outer surface of the solid lubricant surface layer making the coating strain tolerant.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perng, Dung-Ching, E-mail: dcperng@ee.ncku.edu.tw; Center for Micro/Nano Science and Technology, National Cheng Kung University, One University Road, Tainan 701, Taiwan; Lin, Hsueh-Pin
This study reports a high-performance hybrid ultraviolet (UV) photodetector with visible-blind sensitivity fabricated by inserting a poly-(N-vinylcarbazole) (PVK) intermediate layer between low-cost processed Cu{sub 2}O film and ZnO nanorods (NRs). The PVK layer acts as an electron-blocking/hole-transporting layer between the n-ZnO and p-Cu{sub 2}O films. The Cu{sub 2}O/PVK/ZnO NR photodetector exhibited a responsivity of 13.28 A/W at 360 nm, a high detectivity of 1.03 × 10{sup 13} Jones at a low bias of −0.1 V under a low UV light intensity of 24.9 μW/cm{sup 2}. The photo-to-dark current ratios of the photodetector with and without the PVK intermediate layer at a bias of −0.5 V are 1.34 × 10{supmore » 2} and 3.99, respectively. The UV-to-visible rejection ratios (R{sub 360 nm}/R{sub 450 nm}) are 350 and 1.735, respectively. Several features are demonstrated: (a) UV photo-generated holes at the ZnO NRs can effectively be transported through the PVK layer to the p-Cu{sub 2}O layer; (b) the insertion of a PVK buffer layer significantly minimizes the reverse-bias leakage current, which leads to a larger amplification of the photocurrent; and (c) the PVK buffer layer greatly improves the UV-to-visible responsivity ratio, allowing the device to achieve high UV detection sensitivity at a low bias voltage using a very low light intensity.« less
Single layer of Ge quantum dots in HfO2 for floating gate memory capacitors.
Lepadatu, A M; Palade, C; Slav, A; Maraloiu, A V; Lazanu, S; Stoica, T; Logofatu, C; Teodorescu, V S; Ciurea, M L
2017-04-28
High performance trilayer memory capacitors with a floating gate of a single layer of Ge quantum dots (QDs) in HfO 2 were fabricated using magnetron sputtering followed by rapid thermal annealing (RTA). The layer sequence of the capacitors is gate HfO 2 /floating gate of single layer of Ge QDs in HfO 2 /tunnel HfO 2 /p-Si wafers. Both Ge and HfO 2 are nanostructured by RTA at moderate temperatures of 600-700 °C. By nanostructuring at 600 °C, the formation of a single layer of well separated Ge QDs with diameters of 2-3 nm at a density of 4-5 × 10 15 m -2 is achieved in the floating gate (intermediate layer). The Ge QDs inside the intermediate layer are arranged in a single layer and are separated from each other by HfO 2 nanocrystals (NCs) about 8 nm in diameter with a tetragonal/orthorhombic structure. The Ge QDs in the single layer are located at the crossing of the HfO 2 NCs boundaries. In the intermediate layer, besides Ge QDs, a part of the Ge atoms is segregated by RTA at the HfO 2 NCs boundaries, while another part of the Ge atoms is present inside the HfO 2 lattice stabilizing the tetragonal/orthorhombic structure. The fabricated capacitors show a memory window of 3.8 ± 0.5 V and a capacitance-time characteristic with 14% capacitance decay in the first 3000-4000 s followed by a very slow capacitance decrease extrapolated to 50% after 10 years. This high performance is mainly due to the floating gate of a single layer of well separated Ge QDs in HfO 2 , distanced from the Si substrate by the tunnel oxide layer with a precise thickness.
Photocatalytic Nanofiltration Membranes with Self-Cleaning Property for Wastewater Treatment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lv, Yan; Zhang, Chao; He, Ai
Membrane fouling is one of the most severe problems restricting membrane separation technology for wastewater treatment. This work reports a photocatalytic nanofiltration membrane (NFM) with self-cleaning property fabricated using a facile biomimetic mineralization process. In this strategy, a polydopamine (PDA)/polyethyleneimine (PEI) intermediate layer is fabricated on an ultrafiltration membrane via a co-deposition method followed by mineralization of a photocatalytic layer consisting of beta-FeOOH nanorods. The PDA-PEI layer acts both as a nanofiltration selective layer and an intermediate layer for anchoring the beta-FeOOH nanorods via strong coordination complexes between Fe3+ and catechol groups. In visible light, the beta-(F)eOOH layer exhibits efficientmore » photocatalytic activity for degrading dyes through the photo-Fenton reaction in the presence of hydrogen peroxide, endowing the NFM concurrently with effective nanofiltration performance and self-cleaning capability. Moreover, the mineralized NFMs exhibit satisfactory stability under simultaneous filtration and photocatalysis processing, showing great potential in advanced wastewater treatment.« less
Inorganic dual-layer microporous supported membranes
Brinker, C. Jeffrey; Tsai, Chung-Yi; Lu, Yungfeng
2003-03-25
The present invention provides for a dual-layer inorganic microporous membrane capable of molecular sieving, and methods for production of the membranes. The inorganic microporous supported membrane includes a porous substrate which supports a first inorganic porous membrane having an average pore size of less than about 25 .ANG. and a second inorganic porous membrane coating the first inorganic membrane having an average pore size of less than about 6 .ANG.. The dual-layered membrane is produced by contacting the porous substrate with a surfactant-template polymeric sol, resulting in a surfactant sol coated membrane support. The surfactant sol coated membrane support is dried, producing a surfactant-templated polymer-coated substrate which is calcined to produce an intermediate layer surfactant-templated membrane. The intermediate layer surfactant-templated membrane is then contacted with a second polymeric sol producing a polymeric sol coated substrate which is dried producing an inorganic polymeric coated substrate. The inorganic polymeric coated substrate is then calcined producing an inorganic dual-layered microporous supported membrane in accordance with the present invention.
Formation of thin walled ceramic solid oxide fuel cells
Claar, Terry D.; Busch, Donald E.; Picciolo, John J.
1989-01-01
To reduce thermal stress and improve bonding in a high temperature monolithic solid oxide fuel cell (SOFC), intermediate layers are provided between the SOFC's electrodes and electrolyte which are of different compositions. The intermediate layers are comprised of a blend of some of the materials used in the electrode and electrolyte compositions. Particle size is controlled to reduce problems involving differential shrinkage rates of the various layers when the entire structure is fired at a single temperature, while pore formers are provided in the electrolyte layers to be removed during firing for the formation of desired pores in the electrode layers. Each layer includes a binder in the form of a thermosetting acrylic which during initial processing is cured to provide a self-supporting structure with the ceramic components in the green state. A self-supporting corrugated structure is thus formed prior to firing, which the organic components of the binder and plasticizer removed during firing to provide a high strength, high temperature resistant ceramic structure of low weight and density.
Lunar properties from transient and steady magnetic field measurements.
NASA Technical Reports Server (NTRS)
Dyal, P.; Parkin, C. W.
1972-01-01
The electrical conductivity of the lunar interior has been determined from magnetic field step transients measured on the lunar dark side. The simplest model which best fits the data is a spherically symmetric three layer model having a nonconducting outer crust, an intermediate layer with electrical conductivity of .00035 mhos/m, and an inner core with conductivity of .01 mhos/m. Temperatures calculated from these conductivities in the three regions for an example of an olivine moon are as follows: crust, below 440 K; intermediate layer, 890 K; and core, 1240 K. The whole-moon relative permeability has been calculated from the measurements to be 1.03 plus or minus 0.13.
Improved conductivity of indium-tin-oxide film through the introduction of intermediate layer
NASA Astrophysics Data System (ADS)
Ng, S. W.; Yam, F. K.; Beh, K. P.; Tneh, S. S.; Hassan, Z.
2016-09-01
A thin intermediate layer (Ag, AuSn, In, Ni, Sn, SiO2) was individually deposited on glass substrates prior to the deposition of indium-tin-oxide (ITO) thin film by radio-frequency (RF) magnetron sputtering employing ITO target (composition ratio of In2O3:SnO2 = 9:1). The structural, optical and electrical properties were investigated to compare the ITO thin film with and without an intermediate layer. The preferential orientation of all ITO films was along (222) plane. Although all thin films were polycrystalline, the presence of intermediate layer promoted the overall crystallinity. The sheet resistance and resistivity of the ITO film were reduced from ∼68 Ω/□ to ∼29-45 Ω/□, and 16.2 × 10-4 Ω cm up to 7.58 × 10-4 Ω cm, respectively, by inserting a thin metal layer underneath the ITO film, and it is dependent on the degree of crystallization. The optical transmittance in the visible region varies from 40 to 88% for different samples. Based on the evaluation from Tauc plot, the optical band gap falls in the range of 4.02-4.12 eV. Physical film thickness was compared with that evaluated by optical measurement in the visible range and the physical thickness was found to be smaller. Similarly, the carrier concentration/scattering time from Hall effect measurement were also compared with that from optical measurement in the infrared region. Haacke's figure of merit (FOM) was employed to assess the quality of the ITO films, and the highest FOM is credited to ITO/In up to ∼8 × 10-3 Ω-1 in the visible light region.
NASA Astrophysics Data System (ADS)
Al-Sarraf, Abdulhameed R.; Al-Saaidi, Samer A.
2018-05-01
In this study, a number of nanocomposites were prepared by adding magnesium oxide (MgO) with weight percentages (1, 2 & 3)% to cellulose nitrate and sodium silicate as an intermediate layer and other nanocomposites by adding MgO, coal coke and hybrid (MgO & coal coke with ratio 1:1) with weight percentages (1, 2 & 3)% to epoxy resin as final layer. The identity of the used metal is determined by spectrometer OE thermo. The nature and topography of the surface layers were examined by optical microscope and atomic force microscope (AFM). Mechanical properties are indicated by hardness, wear rate, impact strength and adhesion strength. The efficiency of the layers prepared to inhibit corrosion in the oil mineral reservoirs of the oil products distribution company was studied by electrochemical corrosion test in addition to the chemical corrosion test. The used metal is (St-37) according to (ASTM). It was found that the best intermediate layer (cellulose nitrate+3%MgO) and the final layer is the epoxy resin reinforced by 2% hybrid.
Thermal stress analysis of ceramic gas-path seal components for aircraft turbines
NASA Technical Reports Server (NTRS)
Kennedy, F. E.; Bill, R. C.
1979-01-01
Stress and temperature distributions were evaluated numerically for a blade-tip seal system proposed for gas turbine applications. The seal consists of an abradable ceramic layer on metallic backing with intermediate layers between the ceramic layer and metal substrate. The most severe stresses in the seal, as far as failure is concerned, are tensile stresses at the top of the ceramic layer and shear and normal stresses at the layer interfaces. All these stresses reach their maximum values during the deceleration phase of a test engine cycle. A parametric study was carried out to evaluate the influence of various design parameters on these critical stress values. The influences of material properties and geometric parameters of the ceramic, intermediate, and backing layers were investigated. After the parametric study was completed, a seal system was designed which incorporated materials with beneficial elastic and thermal properties in each layer of the seal. An analysis of the proposed seal design shows an appreciable decrease in the magnitude of the maximum critical stresses over those obtained with earlier configurations.
NASA Astrophysics Data System (ADS)
Zhao, Jing; Wong, Pak Kin; Ma, Xinbo; Xie, Zhengchao
2017-01-01
This paper proposes a novel integrated controller with three-layer hierarchical structure to coordinate the interactions among active suspension system (ASS), active front steering (AFS) and direct yaw moment control (DYC). First of all, a 14-degree-of-freedom nonlinear vehicle dynamic model is constructed. Then, an upper layer is designed to calculate the total corrected moment for ASS and intermediate layer based on linear moment distribution. By considering the working regions of the AFS and DYC, the intermediate layer is functionalised to determine the trigger signal for the lower layer with corresponding weights. The lower layer is utilised to separately trace the desired value of each local controller and achieve the local control objectives of each subsystem. Simulation results show that the proposed three-layer hierarchical structure is effective in handling the working region of the AFS and DYC, while the quasi-experimental result shows that the proposed integrated controller is able to improve the lateral and vertical dynamics of the vehicle effectively as compared with a conventional electronic stability controller.
NASA Astrophysics Data System (ADS)
Itagaki, Norikazu; Saito, Shin; Takahashi, Migaku
2009-04-01
Through analyzing the growth mechanism of the Ru layer in a nonmagnetic intermediate layer (NMIL) for perpendicular magnetic recording media, a concept for the NMIL is proposed in order to realize a recording layer of small, highly c-plane oriented grains with no intergranular exchange coupling. It was found that (1) fast Fourier transform analysis of plan-view transmission electron microscopy lattice images of Ru layers revealed that hexagonal close packed Ru grains in a c-plane oriented film readily coalesce with each other due to the disappearance of low-angle tilt boundaries. (2) A promising candidate for a NMIL consists of three individual epitaxially grown functional layers: a large-grain seed layer with a highly oriented sheet texture, a first interlayer of small grains, and a second interlayer of nonmagnetic grains isolated by a segregated oxide. (3) The Ru-SiO2/Ru/Mg NMIL based on the proposed concept exhibited small (diameter: 4.8 nm) Ru grains while retaining a narrow orientation distribution of 4.1°.
Method of making photovoltaic cell
Cruz-Campa, Jose Luis; Zhou, Xiaowang; Zubia, David
2017-06-20
A photovoltaic solar cell comprises a nano-patterned substrate layer. A plurality of nano-windows are etched into an intermediate substrate layer to form the nano-patterned substrate layer. The nano-patterned substrate layer is positioned between an n-type semiconductor layer composed of an n-type semiconductor material and a p-type semiconductor layer composed of a p-type semiconductor material. Semiconductor material accumulates in the plurality of nano-windows, causing a plurality of heterojunctions to form between the n-type semiconductor layer and the p-type semiconductor layer.
Architecture for coated conductors
Foltyn, Stephen R.; Arendt, Paul N.; Wang, Haiyan; Stan, Liliana
2010-06-01
Articles are provided including a base substrate having a layer of an oriented cubic oxide material with a rock-salt-like structure layer thereon, and, a layer of epitaxial titanium nitride upon the layer of an oriented cubic oxide material having a rock-salt-like structure. Such articles can further include thin films of high temperature superconductive oxides such as YBCO upon the layer of epitaxial titanium nitride or upon a intermediate buffer layer upon the layer of epitaxial titanium nitride.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Höger, Ingmar, E-mail: ingmar.hoeger@ipht-jena.de; Gawlik, Annett; Brückner, Uwe
The intermediate layer (IL) between glass substrate and silicon plays a significant role in the optimization of multicrystalline liquid phase crystallized silicon thin film solar cells on glass. This study deals with the influence of the IL on the surface condition and the required chemical surface treatment of the crystallized silicon (mc-Si), which is of particular interest for a-Si:H heterojunction thin film solar cells. Two types of IL were investigated: sputtered silicon nitride (SiN) and a layer stack consisting of silicon nitride and silicon oxide (SiN/SiO). X-ray photoelectron spectroscopy measurements revealed the formation of silicon oxynitride (SiO{sub x}N{sub y}) ormore » silicon oxide (SiO{sub 2}) layers at the surface of the mc-Si after liquid phase crystallization on SiN or SiN/SiO, respectively. We propose that SiO{sub x}N{sub y} formation is governed by dissolving nitrogen from the SiN layer in the silicon melt, which segregates at the crystallization front during crystallization. This process is successfully hindered, when additional SiO layers are introduced into the IL. In order to achieve solar cell open circuit voltages above 500 mV, a removal of the formed SiO{sub x}N{sub y} top layer is required using sophisticated cleaning of the crystallized silicon prior to a-Si:H deposition. However, solar cells crystallized on SiN/SiO yield high open circuit voltage even when a simple wet chemical surface treatment is applied. The implementation of SiN/SiO intermediate layers facilitates the production of mesa type solar cells with open circuit voltages above 600 mV and a power conversion efficiency of 10%.« less
Makabe, Koki; Nakamura, Takashi; Dhar, Debanjan; Ikura, Teikichi; Koide, Shohei; Kuwajima, Kunihiro
2018-04-27
Although many naturally occurring proteins consist of multiple domains, most studies on protein folding to date deal with single-domain proteins or isolated domains of multi-domain proteins. Studies of multi-domain protein folding are required for further advancing our understanding of protein folding mechanisms. Borrelia outer surface protein A (OspA) is a β-rich two-domain protein, in which two globular domains are connected by a rigid and stable single-layer β-sheet. Thus, OspA is particularly suited as a model system for studying the interplays of domains in protein folding. Here, we studied the equilibria and kinetics of the urea-induced folding-unfolding reactions of OspA probed with tryptophan fluorescence and ultraviolet circular dichroism. Global analysis of the experimental data revealed compelling lines of evidence for accumulation of an on-pathway intermediate during kinetic refolding and for the identity between the kinetic intermediate and a previously described equilibrium unfolding intermediate. The results suggest that the intermediate has the fully native structure in the N-terminal domain and the single layer β-sheet, with the C-terminal domain still unfolded. The observation of the productive on-pathway folding intermediate clearly indicates substantial interactions between the two domains mediated by the single-layer β-sheet. We propose that a rigid and stable intervening region between two domains creates an overlap between two folding units and can energetically couple their folding reactions. Copyright © 2018. Published by Elsevier Ltd.
Cho, Kyung-Sang; Heo, Keun; Baik, Chan-Wook; Choi, Jun Young; Jeong, Heejeong; Hwang, Sungwoo; Lee, Sang Yeol
2017-10-10
We report color-selective photodetection from intermediate, monolayered, quantum dots buried in between amorphous-oxide semiconductors. The proposed active channel in phototransistors is a hybrid configuration of oxide-quantum dot-oxide layers, where the gate-tunable electrical property of silicon-doped, indium-zinc-oxide layers is incorporated with the color-selective properties of quantum dots. A remarkably high detectivity (8.1 × 10 13 Jones) is obtained, along with three major findings: fast charge separation in monolayered quantum dots; efficient charge transport through high-mobility oxide layers (20 cm 2 V -1 s -1 ); and gate-tunable drain-current modulation. Particularly, the fast charge separation rate of 3.3 ns -1 measured with time-resolved photoluminescence is attributed to the intermediate quantum dots buried in oxide layers. These results facilitate the realization of efficient color-selective detection exhibiting a photoconductive gain of 10 7 , obtained using a room-temperature deposition of oxide layers and a solution process of quantum dots. This work offers promising opportunities in emerging applications for color detection with sensitivity, transparency, and flexibility.The development of highly sensitive photodetectors is important for image sensing and optical communication applications. Cho et al., report ultra-sensitive photodetectors based on monolayered quantum dots buried in between amorphous-oxide semiconductors and demonstrate color-detecting logic gates.
Numerical modelling of high efficiency InAs/GaAs intermediate band solar cell
NASA Astrophysics Data System (ADS)
Imran, Ali; Jiang, Jianliang; Eric, Debora; Yousaf, Muhammad
2018-01-01
Quantum Dots (QDs) intermediate band solar cells (IBSC) are the most attractive candidates for the next generation of photovoltaic applications. In this paper, theoretical model of InAs/GaAs device has been proposed, where we have calculated the effect of variation in the thickness of intrinsic and IB layer on the efficiency of the solar cell using detailed balance theory. IB energies has been optimized for different IB layers thickness. Maximum efficiency 46.6% is calculated for IB material under maximum optical concentration.
NASA Astrophysics Data System (ADS)
Herguera, J. C.; Herbert, T.; Kashgarian, M.; Charles, C.
2010-05-01
Intermediate ocean circulation changes during the last Glacial Maximum (LGM) in the North Pacific have been linked with Northern Hemisphere climate through air-sea interactions, although the extent and the source of the variability of the processes forcing these changes are still not well resolved. The ventilated volumes and ages in the upper wind driven layer are related to the wind stress curl and surface buoyancy fluxes at mid to high latitudes in the North Pacific. In contrast, the deeper thermohaline layers are more effectively ventilated by direct atmosphere-sea exchange during convective formation of Subantarctic Mode Waters (SAMW) and Antarctic Intermediate Waters (AAIW) in the Southern Ocean, the precursors of Pacific Intermediate Waters (PIW) in the North Pacific. Results reported here show a fundamental change in the carbon isotopic gradient between intermediate and deep waters during the LGM in the eastern North Pacific indicating a deepening of nutrient and carbon rich waters. These observations suggest changes in the source and nature of intermediate waters of Southern Ocean origin that feed PIW and enhanced ventilation processes in the North Pacific, further affecting paleoproductivity and export patters in this basin. Furthermore, oxygen isotopic results indicate these changes may have been accomplished in part by changes in circulation affecting the intermediate depths during the LGM.
NASA Technical Reports Server (NTRS)
Long, W. C.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed and analysis of the Communication and Tracking hardware, generating draft failure modes and potential critical items. The IOA results were then compared to the NASA FMEA/CIL baseline. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter Communication and Tracking hardware. Volume 2 continues the presentation of IOA worksheets.
Independent Orbiter Assessment (IOA): Assessment of the reaction control system, volume 3
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Hartman, Dan W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the aft and forward Reaction Control System (RCS) hardware and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter RCS hardware and EPD and C systems. Volume 3 continues the presentation of IOA worksheets.
Independent Orbiter Assessment (IOA): Assessment of the reaction control system, volume 2
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Hartman, Dan W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the aft and forward Reaction Control System (RCS) hardware and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter RCS hardware and EPD and C systems. Volume 2 continues the presentation of IOA worksheets.
Phase portrait analysis of super solitary waves and flat top solutions
NASA Astrophysics Data System (ADS)
Steffy, S. V.; Ghosh, S. S.
2018-06-01
The phase portrait analysis of super solitary waves has revealed a new kind of intermediate solution which defines the boundary between the two types of super solitary waves, viz., Type I and Type II. A Type I super solitary wave is known to be associated with an intermediate double layer while a Type II solution has no such association. The intermediate solution at the boundary has a flat top structure and is called a flat top solitary wave. Its characteristics resemble an amalgamation of a solitary wave and a double layer. It was found that, mathematically, such kinds of structures may emerge due to the presence of an extra nonlinearity. Although they are relatively unfamiliar in the realm of plasma physics, they have much wider applications in other physical systems.
Tsiourvas, D.; Arkas, M.; Diplas, S.; Mastrogianni, E.
2010-01-01
This work is investigating the chemical grafting on Ti surface of a polymer/calcium phosphate coating of improved adhesion for enhanced bioactivity. For this purpose, a whole new methodology was developed based on covalently attaching a hyperbranched poly(ethylene imine) layer on Ti surface able to promote calcium phosphate formation in a next deposition stage. This was achieved through an intermediate surface silanization step. The research included optimization both of the reaction conditions for covalently grafting the intermediate organosilicon and the subsequent hyperbranched poly(ethylene imine) layers, as well as of the conditions for the mechanical and chemical pretreatment of Ti surface before coating. The reaction steps were monitored employing FTIR and XPS analyses, whereas the surface morphology and structure of the successive coating layers were studied by SEM combined with EDS. The analysis confirmed the successful grafting of the hybrid layer which demonstrated very good ability for hydroxyapatite growth in simulated body fluid. PMID:21069559
Tsiourvas, D; Tsetsekou, A; Arkas, M; Diplas, S; Mastrogianni, E
2011-01-01
This work is investigating the chemical grafting on Ti surface of a polymer/calcium phosphate coating of improved adhesion for enhanced bioactivity. For this purpose, a whole new methodology was developed based on covalently attaching a hyperbranched poly(ethylene imine) layer on Ti surface able to promote calcium phosphate formation in a next deposition stage. This was achieved through an intermediate surface silanization step. The research included optimization both of the reaction conditions for covalently grafting the intermediate organosilicon and the subsequent hyperbranched poly(ethylene imine) layers, as well as of the conditions for the mechanical and chemical pretreatment of Ti surface before coating. The reaction steps were monitored employing FTIR and XPS analyses, whereas the surface morphology and structure of the successive coating layers were studied by SEM combined with EDS. The analysis confirmed the successful grafting of the hybrid layer which demonstrated very good ability for hydroxyapatite growth in simulated body fluid.
NASA Technical Reports Server (NTRS)
Dharmadhikari, V. S.; Grannemann, W. W.
1983-01-01
AES depth profiling data are presented for thin films of BaTiO3 deposited on silicon by RF sputtering. By profiling the sputtered BaTiO3/silicon structures, it was possible to study the chemical composition and the interface characteristics of thin films deposited on silicon at different substrate temperatures. All the films showed that external surface layers were present, up to a few tens of angstroms thick, the chemical composition of which differed from that of the main layer. The main layer had stable composition, whereas the intermediate film-substrate interface consisted of reduced TiO(2-x) oxides. The thickness of this intermediate layer was a function of substrate temperature. All the films showed an excess of barium at the interface. These results are important in the context of ferroelectric phenomena observed in BaTiO3 thin films.
Application of a mixed metal oxide catalyst to a metallic substrate
NASA Technical Reports Server (NTRS)
Sevener, Kathleen M. (Inventor); Lohner, Kevin A. (Inventor); Mays, Jeffrey A. (Inventor); Wisner, Daniel L. (Inventor)
2009-01-01
A method for applying a mixed metal oxide catalyst to a metallic substrate for the creation of a robust, high temperature catalyst system for use in decomposing propellants, particularly hydrogen peroxide propellants, for use in propulsion systems. The method begins by forming a prepared substrate material consisting of a metallic inner substrate and a bound layer of a noble metal intermediate. Alternatively, a bound ceramic coating, or frit, may be introduced between the metallic inner substrate and noble metal intermediate when the metallic substrate is oxidation resistant. A high-activity catalyst slurry is applied to the surface of the prepared substrate and dried to remove the organic solvent. The catalyst layer is then heat treated to bind the catalyst layer to the surface. The bound catalyst layer is then activated using an activation treatment and calcinations to form the high-activity catalyst system.
Method to grow group III-nitrides on copper using passivation layers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Qiming; Wang, George T; Figiel, Jeffrey T
Group III-nitride epilayers can be grown directly on copper substrates using intermediate passivation layers. For example, single crystalline c-plane GaN can be grown on Cu (110) substrates with MOCVD. The growth relies on a low temperature AlN passivation layer to isolate any alloying reaction between Ga and Cu.
Photovoltaic cell with nano-patterned substrate
Cruz-Campa, Jose Luis; Zhou, Xiaowang; Zubia, David
2016-10-18
A photovoltaic solar cell comprises a nano-patterned substrate layer. A plurality of nano-windows are etched into an intermediate substrate layer to form the nano-patterned substrate layer. The nano-patterned substrate layer is positioned between an n-type semiconductor layer composed of an n-type semiconductor material and a p-type semiconductor layer composed of a p-type semiconductor material. Semiconductor material accumulates in the plurality of nano-windows, causing a plurality of heterojunctions to form between the n-type semiconductor layer and the p-type semiconductor layer.
Crustal structure between Lake Mead, Nevada, and Mono Lake, California
Johnson, Lane R.
1964-01-01
Interpretation of a reversed seismic-refraction profile between Lake Mead, Nevada, and Mono Lake, California, indicates velocities of 6.15 km/sec for the upper layer of the crust, 7.10 km/sec for an intermediate layer, and 7.80 km/sec for the uppermost mantle. Phases interpreted to be reflections from the top of the intermediate layer and the Mohorovicic discontinuity were used with the refraction data to calculate depths. The depth to the Moho increases from about 30 km near Lake Mead to about 40 km near Mono Lake. Variations in arrival times provide evidence for fairly sharp flexures in the Moho. Offsets in the Moho of 4 km at one point and 2 1/2 km at another correspond to large faults at the surface, and it is suggested that fracture zones in the upper crust may displace the Moho and extend into the upper mantle. The phase P appears to be an extension of the reflection from the top of the intermediate layer beyond the critical angle. Bouguer gravity, computed for the seismic model of the crust, is in good agreement with the measured Bouguer gravity. Thus a model of the crustal structure is presented which is consistent with three semi-independent sources of geophysical data: seismic-refraction, seismic-reflection, and gravity.
Hydrogen-isotope permeation barrier
Maroni, Victor A.; Van Deventer, Erven H.
1977-01-01
A composite including a plurality of metal layers has a Cu-Al-Fe bronze layer and at least one outer layer of a heat and corrosion resistant metal alloy. The bronze layer is ordinarily intermediate two outer layers of metal such as austenitic stainless steel, nickel alloys or alloys of the refractory metals. The composite provides a barrier to hydrogen isotopes, particularly tritium that can reduce permeation by at least about 30 fold and possibly more below permeation through equal thicknesses of the outer layer material.
Perez-Mendez, V.
1997-01-21
A gamma ray camera is disclosed for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array. 6 figs.
Perez-Mendez, Victor
1997-01-01
A gamma ray camera for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array.
Independent Orbiter Assessment (IOA): Assessment of the reaction control system, volume 4
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Hartman, Dan W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the aft and forward Reaction Control System (RCS) hardware and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter RCS hardware and EPD and C systems. Volume 4 continues the presentation of IOA worksheets and contains the potential critical items list.
Contact inhibition of locomotion determines cell-cell and cell-substrate forces in tissues.
Zimmermann, Juliane; Camley, Brian A; Rappel, Wouter-Jan; Levine, Herbert
2016-03-08
Cells organized in tissues exert forces on their neighbors and their environment. Those cellular forces determine tissue homeostasis as well as reorganization during embryonic development and wound healing. To understand how cellular forces are generated and how they can influence the tissue state, we develop a particle-based simulation model for adhesive cell clusters and monolayers. Cells are contractile, exert forces on their substrate and on each other, and interact through contact inhibition of locomotion (CIL), meaning that cell-cell contacts suppress force transduction to the substrate and propulsion forces align away from neighbors. Our model captures the traction force patterns of small clusters of nonmotile cells and larger sheets of motile Madin-Darby canine kidney (MDCK) cells. In agreement with observations in a spreading MDCK colony, the cell density in the center increases as cells divide and the tissue grows. A feedback between cell density, CIL, and cell-cell adhesion gives rise to a linear relationship between cell density and intercellular tensile stress and forces the tissue into a nonmotile state characterized by a broad distribution of traction forces. Our model also captures the experimentally observed tissue flow around circular obstacles, and CIL accounts for traction forces at the edge.
Independent Orbiter Assessment (IOA): Assessment of the mechanical actuation subsystem, volume 1
NASA Technical Reports Server (NTRS)
Bradway, M. W.; Slaughter, W. T.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine draft failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline that was available. A resolution of each discrepancy from the comparison was provided through additional analysis as required. These discrepancies were flagged as issues, and recommendations were made based on the FMEA data available at the time. This report documents the results of that comparison for the Orbiter Mechanical Actuation System (MAS) hardware. Specifically, the MAS hardware consists of the following components: Air Data Probe (ADP); Elevon Seal Panel (ESP); External Tank Umbilical (ETU); Ku-Band Deploy (KBD); Payload Bay Doors (PBD); Payload Bay Radiators (PBR); Personnel Hatches (PH); Vent Door Mechanism (VDM); and Startracker Door Mechanism (SDM). Criticality was assigned based upon the severity of the effect for each failure mode.
Effect of potential vorticity flux on the circulation in the South China Sea
NASA Astrophysics Data System (ADS)
Zhu, Yaohua; Sun, Junchuan; Wang, Yonggang; Wei, Zexun; Yang, Dezhou; Qu, Tangdong
2017-08-01
This study analyzes temperature and salinity products from the U.S. Navy Generalized Digital Environment Model. To avoid the fictitious assumption of no-motion reference level, a P-vector inverse method is employed to derive geostrophic velocity. Line integral of geostrophic velocity shows evidence for the existence of a sandwiched circulation in the South China Sea (SCS), i.e., cyclonic circulation in the subsurface and deep layers and anticyclonic in the intermediate layer. To reveal the factors responsible for the sandwiched circulation, we derive the potential vorticity equation based on a four-and-a-half-layer quasi-geostrophic model and apply theoretical potential vorticity constraint to density layers. The result shows that the sandwiched circulation is largely induced by planetary potential vorticity flux through lateral boundaries, mainly the Luzon Strait. This dynamical mechanism lies in the fact that the net potential vorticity inflow in the subsurface and deep layers leads to a positive layer-average vorticity in the SCS basin, yielding vortex stretching and a cyclonic basin-wide circulation. On the contrary, the net potential vorticity outflow in the intermediate layer induces a negative layer-average vorticity, generating an anticyclonic basin-wide circulation in the SCS. Furthermore, by illustrating different consequence from depth/density layers, we clarify that density layers are essential for applying theoretical potential vorticity constraint to the isolated deep SCS basin.
Mundy, Christopher J; Curioni, Alessandro; Goldman, Nir; Will Kuo, I-F; Reed, Evan J; Fried, Laurence E; Ianuzzi, Marcella
2008-05-14
We report herein ab initio molecular dynamics simulations of graphite under shock compression in conjunction with the multiscale shock technique. Our simulations reveal that a novel short-lived layered diamond intermediate is formed within a few hundred of femtoseconds upon shock loading at a shock velocity of 12 kms (longitudinal stress>130 GPa), followed by formation of cubic diamond. The layered diamond state differs from the experimentally observed hexagonal diamond intermediate found at lower pressures and previous hydrostatic calculations in that a rapid buckling of the graphitic planes produces a mixture of hexagonal and cubic diamond (layered diamond). Direct calculation of the x-ray absorption spectra in our simulations reveals that the electronic structure of the final state closely resembles that of compressed cubic diamond.
Deep Arctic Ocean warming during the last glacial cycle
Cronin, T. M.; Dwyer, G.S.; Farmer, J.; Bauch, H.A.; Spielhagen, R.F.; Jakobsson, M.; Nilsson, J.; Briggs, W.M.; Stepanova, A.
2012-01-01
In the Arctic Ocean, the cold and relatively fresh water beneath the sea ice is separated from the underlying warmer and saltier Atlantic Layer by a halocline. Ongoing sea ice loss and warming in the Arctic Ocean have demonstrated the instability of the halocline, with implications for further sea ice loss. The stability of the halocline through past climate variations is unclear. Here we estimate intermediate water temperatures over the past 50,000 years from the Mg/Ca and Sr/Ca values of ostracods from 31 Arctic sediment cores. From about 50 to 11 kyr ago, the central Arctic Basin from 1,000 to 2,500 m was occupied by a water mass we call Glacial Arctic Intermediate Water. This water mass was 1–2 °C warmer than modern Arctic Intermediate Water, with temperatures peaking during or just before millennial-scale Heinrich cold events and the Younger Dryas cold interval. We use numerical modelling to show that the intermediate depth warming could result from the expected decrease in the flux of fresh water to the Arctic Ocean during glacial conditions, which would cause the halocline to deepen and push the warm Atlantic Layer into intermediate depths. Although not modelled, the reduced formation of cold, deep waters due to the exposure of the Arctic continental shelf could also contribute to the intermediate depth warming.
Histology assessment of bipolar coagulation and argon plasma coagulation on digestive tract
Garrido, Teresa; Baba, Elisa R; Wodak, Stephanie; Sakai, Paulo; Cecconello, Ivan; Maluf-Filho, Fauze
2014-01-01
AIM: To analyze the effect of bipolar electrocoagulation and argon plasma coagulation on fresh specimens of gastrointestinal tract. METHODS: An experimental evaluation was performed at Hospital das Clinicas of the University of São Paulo, on 31 fresh surgical specimens using argon plasma coagulation and bipolar electrocoagulation at different time intervals. The depth of tissue damage was histopathologically analyzed by single senior pathologist unaware of the coagulation method and power setting applied. To analyze the results, the mucosa was divided in superficial mucosa (epithelial layer of the esophagus and superficial portion of the glandular layer of the stomach and colon) intermediate mucosa (until the lamina propria of the esophagus and until the bottom of the glandular layer of the stomach and colon) and muscularis mucosa. Necrosis involvement of the layers was compared in several combinations of power and time interval. RESULTS: Involvement of the intermediate mucosa of the stomach and of the muscularis mucosa of the three organs was more frequent when higher amounts of energy were used with argon plasma. In the esophagus and in the colon, injury of the intermediate mucosa was frequent, even when small amounts of energy were used. The use of bipolar electrocoagulation resulted in more frequent involvement of the intermediate mucosa and of the muscularis mucosa of the esophagus and of the colon when higher amounts of energy were used. In the stomach, these involvements were rare. The risk of injury of the muscularis propria was significant only in the colon when argon plasma coagulation was employed. CONCLUSION: Tissue damage after argon plasma coagulation is deeper than bipolar electrocoagulation. Both of them depend on the amount of energy used. PMID:25031789
Capturing a flavivirus pre-fusion intermediate.
Kaufmann, Bärbel; Chipman, Paul R; Holdaway, Heather A; Johnson, Syd; Fremont, Daved H; Kuhn, Richard J; Diamond, Michael S; Rossmann, Michael G
2009-11-01
During cell entry of flaviviruses, low endosomal pH triggers the rearrangement of the viral surface glycoproteins to a fusion-active state that allows the release of the infectious RNA into the cytoplasm. In this work, West Nile virus was complexed with Fab fragments of the neutralizing mAb E16 and was subsequently exposed to low pH, trapping the virions in a pre-fusion intermediate state. The structure of the complex was studied by cryo-electron microscopy and provides the first structural glimpse of a flavivirus fusion intermediate near physiological conditions. A radial expansion of the outer protein layer of the virion was observed compared to the structure at pH 8. The resulting approximately 60 A-wide shell of low density between lipid bilayer and outer protein layer is likely traversed by the stem region of the E glycoprotein. By using antibody fragments, we have captured a structural intermediate of a virus that likely occurs during cell entry. The trapping of structural transition states by antibody fragments will be applicable for other processes in the flavivirus life cycle and delineating other cellular events that involve conformational rearrangements.
NASA Astrophysics Data System (ADS)
Kato, Zenta; Kashima, Ryo; Tatsumi, Kohei; Fukuyama, Shinnosuke; Izumiya, Koichi; Kumagai, Naokazu; Hashimoto, Koji
2016-12-01
For oxygen formation without forming chlorine in seawater electrolysis for hydrogen production we have been using the anode consisting of three layers of MnO2-type multiple oxide catalyst, intermediate layer and titanium substrate. The intermediate layer was used for prevention of oxidation of the titanium substrate during anodic polarization for oxygen evolution and was prepared by calcination of butanol solutions of H2IrCl6 and SnCl4 coated on titanium. The protectiveness of Ir1-xSnxO2 layer formed was directly examined using Ir1-xSnxO2/Ti anodes in H2SO4 solution changing the preparation conditions of the layer. When the sum of Ir4+ and Sn4+ was 0.1 M, the highest protectiveness was observed at 0.06 M Sn4+. Although an increase in calcination temperature led to the formation of Ir1-x-ySnxTiyO2 triple oxide with a slightly lower catalytic activity for oxygen evolution, the anode calcined at 450 °C showed the highest protectiveness.
NASA Astrophysics Data System (ADS)
Ferhati, H.; Djeffal, F.
2018-03-01
In this work, versatile CdS/Cu 2 ZnSnS 4 (CZTS) solar cell designs based on intermediate metallic sub-layers (Au, Ti, and Ag) engineering are proposed for enhancing light-scattering behavior and reducing recombination losses. The idea behind this work is to generate optical confinement regions in the CZTS absorber layer to achieve an improved absorption and appropriate antireflection effects. Moreover, the ultra-thin metal at the CZTS/Mo interface can be helpful for reducing the series resistance, where it behaves like a blocking layer for the Sulfur diffusion. We further combine the proposed designs with Particle Swarm Optimization (PSO)-based approach to achieve broadband absorption and boost the conversion efficiency. It is found that the optimized design with Ti sub-layer improves the CZTS solar cell properties, where it yields 31% improvement in short-circuit current and 60% in the power efficiency over the conventional one. Therefore, the optimized designs provide the opportunity for bridging the gap between improving the optical behavior and reducing the recombination losses.
Recirculation of the Canary Current in fall 2014
NASA Astrophysics Data System (ADS)
Hernández-Guerra, Alonso; Espino-Falcón, Elisabet; Vélez-Belchí, Pedro; Dolores Pérez-Hernández, M.; Martínez-Marrero, Antonio; Cana, Luis
2017-10-01
Hydrographic measurements together with Ship mounted Acoustic Doppler Current Profilers and Lowered Acoustic Doppler Current Profilers (LADCP) obtained in October 2014 are used to describe water masses, geostrophic circulation and mass transport of the Canary Current System, as the Eastern Boundary of the North Atlantic Subtropical Gyre. Geostrophic velocities are adjusted to velocities from LADCP data to estimate an initial velocity at the reference layer. The adjustment results in a northward circulation at the thermocline layers over the African slope from an initial convergent flow. Final reference velocities and consequently absolute circulation are estimated from an inverse box model applied to an ocean divided into 13 neutral density layers. This allows us to evaluate mass fluxes consistent with the thermal wind equation and mass conservation. Ekman transport is estimated from the wind data derived from the Weather Research and Forecasting model. Ekman transport is added to the first layer and adjusted with the inverse model. The Canary Current located west of Lanzarote Island transports to the south a mass of - 1.5 ± 0.7 Sv (1 Sv = 106 m3 s- 1 ≈ 109 kg s- 1) of North Atlantic Central Water at the surface and thermocline layers ( 0-700 m). In fall 2014, hydrographic data shows that the Canary Current in the thermocline (below at about 80 m depth to 700 m) recirculates to the north over the African slope and flows through the Lanzarote Passage. At intermediate layers ( 700-1400 m), the Intermediate Poleward Undercurrent transports northward a relatively fresh Antarctic Intermediate Water in the range of 0.8 ± 0.4 Sv through the Lanzarote Passage and west of Lanzarote Island beneath the recirculation of the Canary Current.
Schares, G; Herrmann, D C; Maksimov, P; Matzkeit, B; Conraths, F J; Moré, G; Preisinger, R; Weigend, S
2017-09-01
Three genetically different clones of Toxoplasma gondii, also different in mouse virulence, were studied by experimental infection in chickens. For the experiments, four chicken lines were used, which differed in phylogenetic origin and performance level: two white egg layer lines, one with high laying performance (WLA), one with low (R11) and two brown layer lines, also displaying high (BLA) and low (L68) egg number. Chickens were intraperitoneally infected with three different T. gondii isolates representing type IIxIII recombinant clones, i.e. showing both, type II- and type III-specific alleles. These clones (K119/2 2C10, B136/1 B6H6, K119/2 A7) had exhibited virulence differences in a mouse model. In chickens, a significantly higher mortality was observed in white layer lines, but not in brown layer lines, suggesting that differences in the phylogenetic background may influence the susceptibility of chickens for toxoplasmosis. In addition, antibody (IgY) levels varied in surviving chickens at 31 days post infection. While low to intermediate antibody levels were observed in white layers, intermediate to high levels were measured in brown layers. Infection with a T. gondii clone showing low chicken virulence resulted in higher antibody levels in all chicken lines compared to infection with T. gondii clones of intermediate or high chicken virulence. This was in agreement with the parasite load as determined by real-time PCR. Overall, results show that progeny resulting from natural sexual recombination of T. gondii clonal lineages, may differ in their virulence for mice and chickens. Copyright © 2016 Elsevier Inc. All rights reserved.
Characterization of the Shear Layer in a Mach 3 Shock/Turbulent Boundary Layer Interaction
NASA Astrophysics Data System (ADS)
Helm, Clara; Priebe, Stephan; Li, Justine; Dupont, Pierre; Martin, Pino
2013-11-01
The unsteady motion of fully separated shock and turbulent boundary layers interactions (STBLIs) is characterized by an energized low-frequency motion that is two orders of magnitude lower than that of the incoming turbulence. In addition, the spectra shows significant energy content at frequency that is between the characteristic low frequency and the higher frequency motions of the incoming turbulence. The intermediate frequency content is hypothesized to be associated with the existence of Kelvin-Helmholtz type structures, which form in the shear layer downstream of the separation shock and are shed near the reattachment point downstream of the interaction. The current research is concerned with investigating the origins of the intermediate frequencies, and how they may be related to or possibly influence the low-frequency unsteadiness. Specifically, LES data of a Mach 3 STBLI over a 24o ramp are used to estimate convection velocities within the shear layer downstream of the shock. In addition, Brown and Thomas type correlations are used to estimate time and length scales of the eddies in the shear layer. This work is supported by the Air Force Office of Scientific Research under grant AF/9550-10-1-0164.
Water generation and transport through the high-pressure ice layers of Titan and Ganymede
NASA Astrophysics Data System (ADS)
Kalousova, K.; Sotin, C.; Choblet, G.; Tobie, G.; Grasset, O.
2017-09-01
We investigate the generation and transport of water through the high-pressure (HP) ice layers of Ganymede and Titan using a numerical model of two-phase convection in 2D geometry. Our results suggest that water can be generated at the silicate/HP ice interface for small to intermediate values of Rayleigh number (Ra 1.e8-1.e10) while no melt is generated for the higher values (Ra 1.e11). If generated, water is transported through the layer by the upwelling plumes and, depending on the vigor of convection, it stays liquid (smaller Ra) or it may freeze (intermediate Ra) before melting again as the plume reaches the temperate layer at the interface with the ocean. The thickness of this layer as well as the amount of melt that is extracted from it is controlled by the HP ice permeability. This process may enable the transfer of volatiles and salts that might have been leached from silicates by the meltwater. Since the HP ice layer is much thinner on Titan than on Ganymede, it is probably more permeable for volatiles and salts leached from the silicate core.
NASA Technical Reports Server (NTRS)
Voss, H. D.; Smith, L. G.
1974-01-01
An explanation was developed for the formation, near midnight at midlatitudes, of a broad electron density layer extending approximately from 120 to 180 km and usually referred to as the intermediate E layer. The responsible mechanism is believed to be the converging vertical ion drifts resulting from winds of the solar semidiurnal tide. Numerical solutions of the continuity equation appropriate to the intermediate layer is described for particular models of ion drift, diffusion coefficents, and ionization production. Analysis of rocket observations of the layer show that the ionization rate is highly correlated with the planetary geomagnetic index, K sub p. Particle flux measurements support the idea that energetic electrons are the principal source of this ionization. A semiconductor spectrometer experiment for investigation of the particle flux, spectrum, and angular properties was designed and successfully flown on a Nike Apache rocket. A detailed description of the theory, design, and calibration of the experiment and some preliminary results presented.
Effect of 3C-SiC intermediate layer in GaN—based light emitting diodes grown on Si(111) substrate
NASA Astrophysics Data System (ADS)
Zhu, Youhua; Wang, Meiyu; Li, Yi; Tan, Shuxin; Deng, Honghai; Guo, Xinglong; Yin, Haihong; Egawa, Takashi
2017-03-01
GaN-based light emitting diodes (LEDs) have been grown by metalorganic chemical vapor deposition on Si(111) substrate with and without 3C-SiC intermediate layer (IL). Structural property has been characterized by means of atomic force microscope, X-ray diffraction, and transmission electron microscope measurements. It has been revealed that a significant improvement in crystalline quality of GaN and superlattice epitaxial layers can be achieved by using 3C-SiC as IL. Regarding of electrical and optical characteristics, it is clearly observed that the LEDs with its IL have a smaller leakage current and higher light output power comparing with the LEDs without IL. The better performance of LEDs using 3C-SiC IL can be contributed to both of the improvements in epitaxial layers quality and light extraction efficiency. As a consequence, in terms of optical property, a double enhancement of the light output power and external quantum efficiency has been realized.
Subduction of a low-salinity water mass around the Xisha Islands in the South China Sea.
Huang, Zhida; Zhuang, Wei; Liu, Hailong; Hu, Jianyu
2018-02-15
Based on three climatologically observed temperature and salinity datasets (i.e., GDEM-V3, SCSPOD14 and WOA13), this paper reports a low-salinity (~34.32) water mass in the subsurface-to-intermediate layer around the Xisha Islands in the South China Sea. This water mass mainly subducts from the surface layer into the intermediate layer, characterized by a relatively low potential vorticity tongue extending from the bottom of mixed layer to the thermocline, and accompanied by a thermocline ventilation in spring (especially in April). The potential dynamics are the joint effects of negative wind stress curl, and an anticyclonic eddy triggered by the inherent topographic effect of the Xisha Islands, reflecting that downward vertical motion dominates the subduction. Despite lacking of the homogenous temperature and density, the low-salinity water mass is to some extent similar to the classic mode water and can be regarded as a deformed mode water in the South China Sea.
Site-specific Installation and Study of Electroactive Units in Every Layer of Dendrons
Azagarsamy, Malar A.; Krishnamoorthy, Kothandam; Sivanandan, Kulandaivelu; Thayumanavan, S.
2009-01-01
While encapsulation of functional groups at the core of dendrimers is well-understood, very little is known about their intermediate layers or even the periphery. Here we report on a systematic investigation of every layer of dendrimers by incorporating a single ferrocene unit in well-defined locations in dendrons. Site-specific incorporation of the ferrocene unit was achieved utilizing the dendrimer sequencing methodology. We show here that the redox potential values of ferrocene at intermediate layers were remarkably different from that at the core and the periphery. While redox potential values were location-dependent, no significant change in the rate of heterogeneous electron transfer (k0) was observed with respect to locations. This was attributed to the possibility that free rotation of dendrimer nullifies the distance between the electrode and ferrocene unit. Finally, we also show that no Faradaic current was observed for the amphiphilic assemblies of these dendrons, while the same dendron did exhibit significant Faradaic current in non-assembling solvent environments. PMID:19905006
What makes a feather shine? A nanostructural basis for glossy black colours in feathers.
Maia, Rafael; D'Alba, Liliana; Shawkey, Matthew D
2011-07-07
Colours in feathers are produced by pigments or by nanostructurally organized tissues that interact with light. One of the simplest nanostructures is a single layer of keratin overlying a linearly organized layer of melanosomes that create iridescent colours of feather barbules through thin-film interference. Recently, it has been hypothesized that glossy (i.e. high specular reflectance) black feathers may be evolutionarily intermediate between matte black and iridescent feathers, and thus have a smooth keratin layer that produces gloss, but not the layered organization of melanosomes needed for iridescence. However, the morphological bases of glossiness remain unknown. Here, we use a theoretical approach to generate predictions about morphological differences between matte and glossy feathers that we then empirically test. Thin-film models predicted that glossy spectra would result from a keratin layer 110-180 nm thick and a melanin layer greater than 115 nm thick. Transmission electron microscopy data show that nanostructure of glossy barbules falls well within that range, but that of matte barbules does not. Further, glossy barbules had a thinner and more regular keratin cortex, as well as a more continuous underlying melanin layer, than matte barbules. Thus, their quasi-ordered nanostructures are morphologically intermediate between matte black and iridescent feathers, and perceived gloss may be a form of weakly chromatic iridescence.
Independent Orbiter Assessment (IOA): Assessment of the reaction control system, volume 5
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Hartman, Dan W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the aft and forward Reaction Control System (RCS) hardware and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter RCS hardware and EPD and C systems. Volume 5 contains detailed analysis and superseded analysis worksheets and the NASA FMEA to IOA worksheet cross reference and recommendations.
NASA Technical Reports Server (NTRS)
Long, W. C.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed and analysis of the Communication and Tracking hardware, generating draft failure modes and potential critical items. The IOA results were then compared to the NASA FMEA/CIL baseline. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter Communication and Tracking hardware. Volume 3 continues the presentation of IOA worksheets and contains the potential critical items list, detailed analysis, and the NASA FMEA to IOA worksheet cross reference and recommendations.
NASA Astrophysics Data System (ADS)
El-Kader, M. S. A.; Godet, J.-L.; Gustafsson, M.; Maroulis, G.
2018-04-01
Quantum mechanical lineshapes of collision-induced absorption (CIA), collision-induced light scattering (CILS) and collision-induced hyper-Rayleigh scattering (CIHR) at room temperature (295 K) are computed for gaseous mixtures of molecular hydrogen with neon, krypton and xenon. The induced spectra are detected using theoretical values for induced dipole moment, pair-polarizability trace and anisotropy, hyper-polarizability and updated intermolecular potentials. Good agreement is observed for all spectra when the literature and the present potentials which are constructed from the transport and thermo-physical properties are used.
NASA Astrophysics Data System (ADS)
Chen, Y.; Huang, X. J.; Kong, J. X.
2018-03-01
In this paper, the focused ion beam was used to study the subsurface deformed layer of single crystal copper caused by the nanoscale single-point diamond fly cutting, and the possibility of using nanometer ultra-precision cutting to remove the larger deformation layer caused by traditional rough cutting process was explored. The maximum cutting thickness of single-point diamond cutting was about 146 nm, and the surface of the single-crystal copper after cutting was etched and observed by using the focused ion beam method. It was found that the morphology of the near-surface layer and the intermediate layer of the copper material were larger differences: the near-surface of the material was smaller and more compact, and the intermediate material layer of the material was more coarse sparse. The results showed that the traditional precision cutting would residual significant subsurface deformed layer and the thickness was on micron level. Even more, the subsurface deformed layer was obviously removed from about 12μm to 5μm after single-point diamond fly cutting in this paper. This paper proved that the large-scale subsurface deformed layer caused by traditional cutting process could be removed by nanometer ultra-precision cutting. It was of great significance to further establish the method that control of the deformation of weak rigid components by reducing the depth of the subsurface deformed layers.
NASA Astrophysics Data System (ADS)
Ishihara, S.; Tamura, S.; Ishii, K.; Kataoka, H.
2016-09-01
To study the effects of the boundary layer on the deflagration to detonation transition (DDT) process, the mixture behind an incident shock wave was ignited using laser breakdown. Ignition timing was controlled so that the interaction of the resulting flame with a laminar or turbulent boundary layer could be examined. In the case of the interaction with a laminar boundary layer, wrinkling of the flame was observed after the flame reached the corner of the channel. On the other hand, interaction with the turbulent boundary layer distorted the flame front and increased the spreading rate of the flame followed by prompt DDT. The inner structure of the turbulent boundary layer plays an important role in the DDT process. The region that distorted the flame within the turbulent boundary layer was found to be the intermediate region 0.01< y/δ < 0.4, where y is the distance from the wall and δ is the boundary layer thickness. The flame disturbance by the turbulent motions is followed by the flame interaction with the inner layer near the wall, which in turn generates a secondary-ignition kernel that produced a spherical accelerating flame, which ultimately led to the onset of detonation. After the flame reached the intermediate region, the time required for DDT was independent of the ignition position. The effect of the boundary layer on the propagating flame, thus, became relatively small after the accelerating flame was generated.
Seismic imaging of slab metamorphism and genesis of intermediate-depth intraslab earthquakes
NASA Astrophysics Data System (ADS)
Hasegawa, Akira; Nakajima, Junichi
2017-12-01
We review studies of intermediate-depth seismicity and seismic imaging of the interior of subducting slabs in relation to slab metamorphism and their implications for the genesis of intermediate-depth earthquakes. Intermediate-depth events form a double seismic zone in the depth range of c. 40-180 km, which occur only at locations where hydrous minerals are present, and are particularly concentrated along dehydration reaction boundaries. Recent studies have revealed detailed spatial distributions of these events and a close relationship with slab metamorphism. Pressure-temperature paths of the crust for cold slabs encounter facies boundaries with large H2O production rates and positive total volume change, which are expected to cause highly active seismicity near the facies boundaries. A belt of upper-plane seismicity in the crust nearly parallel to 80-90 km depth contours of the slab surface has been detected in the cold Pacific slab beneath eastern Japan, and is probably caused by slab crust dehydration with a large H2O production rate. A seismic low-velocity layer in the slab crust persists down to the depth of this upper-plane seismic belt, which provides evidence for phase transformation of dehydration at this depth. Similar low-velocity subducting crust closely related with intraslab seismicity has been detected in several other subduction zones. Seismic tomography studies in NE Japan and northern Chile also revealed the presence of a P-wave low-velocity layer along the lower plane of a double seismic zone. However, in contrast to predictions based on the serpentinized mantle, S-wave velocity along this layer is not low. Seismic anisotropy and pore aspect ratio may play a role in generating this unique structure. Although further validation is required, observations of these distinct low P-wave velocities along the lower seismic plane suggest the presence of hydrated rocks or fluids within that layer. These observations support the hypothesis that dehydration-derived H2O causes intermediate-depth intraslab earthquakes. However, it is possible that dual mechanisms generate these earthquakes; the initiation of earthquake rupture may be caused by local excess pore pressure from H2O, and subsequent ruptures may propagate through thermal shear instability. In either case, slab-derived H2O plays an important role in generating intermediate-depth events.
Photo-crystallization in a-Se layer structures: Effects of film-substrate interface-rigidity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lindberg, G. P.; Gross, N.; Weinstein, B. A.
Amorphous selenium (a-Se) films deposited on rigid substrates can undergo photo-induced crystallization (PC) even at temperatures (T) well below the glass transition, T{sub g} ∼ 313 K. Substrate-generated shear strain is known to promote the PC process. In the present work, we explore the influence of different substrates (Si and glass), and different film-layer-substrate combinations, on the PC in a variety of a-Se films and film-structures. The intermediate layers (indium tin oxide and polyimide) are chosen to promote conductivity and/or to be a buffer against interface strain in structures of interest for digital imaging applications. The PC characteristics in these samples are evaluatedmore » and compared using optical microscopy, atomic-force microscopy, Raman mapping, and T-dependent Raman spectroscopy. Both the presence of a soft intermediate layer, and the thermal softening that occurs for T increasing through T{sub g}, inhibit the tendency for the onset of PC. The extensive PC mapping results in the wide range of samples studied here, as well as the suppression of PC near T{sub g} in this array of samples, strongly support the generality of this behavior. As a consequence, one may expect that the stability of a-Se films against PC can be enhanced by decreasing the rigidity of the film-substrate interface. In this regard, advanced film structures that employ flexible substrates, soft intermediate layers, and/or are designed to be operated near T{sub g} should be explored.« less
Atomic-Level Properties of Thermal Barrier Coatings: Characterization of Metal-Ceramic Interfaces
2001-01-01
these cases metal - metal bonds were stronger than metal - substrate bonds, thus predicting a 3D (cluster) growth mode as opposed to layer-by-layer...coat layer must be deposited. The top coat serves as the insulator and the bond coat mediates contact between the top coat and metal alloy substrate ...in thermomechanical properties between a YSZ top coat and a metal -alloy substrate is enough to require the introduction of an intermediate layer. This
Sarin, V.K.
1991-07-30
A process is disclosed for depositing a high temperature stress and oxidation resistant coating on a silicon nitride- or silicon carbide-based substrate body. A gas mixture is passed over the substrate at about 900--1500 C and about 1 torr to about ambient pressure. The gas mixture includes one or more halide vapors with other suitable reactant gases. The partial pressure ratios, flow rates, and process times are sufficient to deposit a continuous, fully dense, adherent coating. The halide and other reactant gases are gradually varied during deposition so that the coating is a graded coating of at least two layers. Each layer is a graded layer changing in composition from the material over which it is deposited to the material of the layer and further to the material, if any, deposited thereon, so that no clearly defined compositional interfaces exist. The gases and their partial pressures are varied according to a predetermined time schedule and the halide and other reactant gases are selected so that the layers include (a) an adherent, continuous intermediate layer about 0.5-20 microns thick of an aluminum nitride or an aluminum oxynitride material, over and chemically bonded to the substrate body, and (b) an adherent, continuous first outer layer about 0.5-900 microns thick including an oxide of aluminum or zirconium over and chemically bonded to the intermediate layer.
Sarin, Vinod K.
1991-01-01
A process for depositing a high temperature stress and oxidation resistant coating on a silicon nitride- or silicon carbide-based substrate body. A gas mixture is passed over the substrate at about 900.degree.-1500.degree. C. and about 1 torr to about ambient pressure. The gas mixture includes one or more halide vapors with other suitable reactant gases. The partial pressure ratios, flow rates, and process times are sufficient to deposit a continuous, fully dense, adherent coating. The halide and other reactant gases are gradually varied during deposition so that the coating is a graded coating of at least two layers. Each layer is a graded layer changing in composition from the material over which it is deposited to the material of the layer and further to the material, if any, deposited thereon, so that no clearly defined compositional interfaces exist. The gases and their partial pressures are varied according to a predetermined time schedule and the halide and other reactant gases are selected so that the layers include (a) an adherent, continuous intermediate layer about 0.5-20 microns thick of an aluminum nitride or an aluminum oxynitride material, over and chemically bonded to the substrate body, and (b) an adherent, continuous first outer layer about 0.5-900 microns thick including an oxide of aluminum or zirconium over and chemically bonded to the intermediate layer.
NASA Astrophysics Data System (ADS)
Prosviryakov, E. Yu.; Spevak, L. F.
2017-12-01
A new exact solution of the Oberbeck-Boussinesq system is found. The Marangoni thermocapillary convection in an infinite fluid layer is described. It is demonstrated that the specification of tangential stresses at both boundaries of the layered velocity field is nonstationary. Velocities describe a superposition of unidirectional flows with an intermediate time interval when there are counterflows.
ADAM13 cleavage of cadherin-11 promotes CNC migration independently of the homophilic binding site.
Abbruzzese, Genevieve; Becker, Sarah F; Kashef, Jubin; Alfandari, Dominique
2016-07-15
The cranial neural crest (CNC) is a highly motile population of cells that is responsible for forming the face and jaw in all vertebrates and perturbing their migration can lead to craniofacial birth defects. Cell motility requires a dynamic modification of cell-cell and cell-matrix adhesion. In the CNC, cleavage of the cell adhesion molecule cadherin-11 by ADAM13 is essential for cell migration. This cleavage generates a shed extracellular fragment of cadherin-11 (EC1-3) that possesses pro-migratory activity via an unknown mechanism. Cadherin-11 plays an important role in modulating contact inhibition of locomotion (CIL) in the CNC to regulate directional cell migration. Here, we show that while the integral cadherin-11 requires the homophilic binding site to promote CNC migration in vivo, the EC1-3 fragment does not. In addition, we show that increased ADAM13 activity or expression of the EC1-3 fragment increases CNC invasiveness in vitro and blocks the repulsive CIL response in colliding cells. This activity requires the presence of an intact homophilic binding site on the EC1-3 suggesting that the cleavage fragment may function as a competitive inhibitor of cadherin-11 adhesion in CIL but not to promote cell migration in vivo. Copyright © 2015. Published by Elsevier Inc.
Contact inhibition of locomotion determines cell–cell and cell–substrate forces in tissues
Zimmermann, Juliane; Camley, Brian A.; Rappel, Wouter-Jan; Levine, Herbert
2016-01-01
Cells organized in tissues exert forces on their neighbors and their environment. Those cellular forces determine tissue homeostasis as well as reorganization during embryonic development and wound healing. To understand how cellular forces are generated and how they can influence the tissue state, we develop a particle-based simulation model for adhesive cell clusters and monolayers. Cells are contractile, exert forces on their substrate and on each other, and interact through contact inhibition of locomotion (CIL), meaning that cell–cell contacts suppress force transduction to the substrate and propulsion forces align away from neighbors. Our model captures the traction force patterns of small clusters of nonmotile cells and larger sheets of motile Madin–Darby canine kidney (MDCK) cells. In agreement with observations in a spreading MDCK colony, the cell density in the center increases as cells divide and the tissue grows. A feedback between cell density, CIL, and cell–cell adhesion gives rise to a linear relationship between cell density and intercellular tensile stress and forces the tissue into a nonmotile state characterized by a broad distribution of traction forces. Our model also captures the experimentally observed tissue flow around circular obstacles, and CIL accounts for traction forces at the edge. PMID:26903658
ADAM13 cleavage of cadherin-11 promotes CNC migration independently of the homophilic binding site
Kashef, Jubin; Alfandari, Dominique
2015-01-01
The cranial neural crest (CNC) is a highly motile population of cells that is responsible for forming the face and jaw in all vertebrates and perturbing their migration can lead to craniofacial birth defects. Cell motility requires a dynamic modification of cell–cell and cell-matrix adhesion. In the CNC, cleavage of the cell adhesion molecule cadherin-11 by ADAM13 is essential for cell migration. This cleavage generates a shed extracellular fragment of cadherin-11 (EC1-3) that possesses pro-migratory activity via an unknown mechanism. Cadherin-11 plays an important role in modulating contact inhibition of locomotion (CIL) in the CNC to regulate directional cell migration. Here, we show that while the integral cadherin-11 requires the homophilic binding site to promote CNC migration in vivo, the EC1-3 fragment does not. In addition, we show that increased ADAM13 activity or expression of the EC1-3 fragment increases CNC invasiveness in vitro and blocks the repulsive CIL response in colliding cells. This activity requires the presence of an intact homophilic binding site on the EC1-3 suggesting that the cleavage fragment may function as a competitive inhibitor of cadherin-11 adhesion in CIL but not to promote cell migration in vivo. PMID:26206614
Reiter, Shunit; Schalock, Robert L
2008-03-01
This study provides a description of the design and development of guidelines and programs for a national core curriculum for special education in Israel. Israel was exposed during the 1970s to the ideology of normalization. Later on, toward the end of the 1980s, the concept of quality of life was added. Several research studies were conducted, resulting in the following core ideas about education: a shift of emphasis from teaching independent-living skills to teaching autonomy, self-awareness, self-direction, and interdependence is required. On the basis of these ideas, a new model of instruction was devised and termed the 'cycle of internalized learning' (CIL). The CIL is based on a holistic orientation toward the student and builds on abilities rather than disabilities. The peer group is the basic unit of instruction. Attention is on processes and outcomes. The CIL involves several clearly defined teaching steps: (i) opening--the presentation of the subject matter; (ii) discussion--a conceptual analysis of the subject; (iii) open conversation--students discuss the issues they raised during the first session, express their personal life experiences while applying the new concepts they learned, and suggest possible solutions to problems; (iv) trying out the solutions suggested by students; and (v) repeated discussions, to arrive at personal and social conclusions. Currently there are three published units of the CIL: (i) Social Education, (ii) Career Education, and (iii) Towards Leaving Home for Independent Living in the Community. The fourth unit, on citizenship education through the use of computers, is in its final stages of preparation. The success of the implementation of the program is expressed both at the students' level--as an enhanced sense of self-worth and self-confidence, as well as enhanced academic achievements and social skills--and at the teachers' level--as a paradigm shift from a medical model of approach to students with disabilities to a social and humanistic one.
Low stress polysilicon film and method for producing same
NASA Technical Reports Server (NTRS)
Heuer, Arthur H. (Inventor); Kahn, Harold (Inventor); Yang, Jie (Inventor)
2001-01-01
Multi-layer assemblies of polysilicon thin films having predetermined stress characteristics and techniques for forming such assemblies are disclosed. In particular, a multi-layer assembly of polysilicon thin film may be produced that has a stress level of zero, or substantially so. The multi-layer assemblies comprise at least one constituent thin film having a tensile stress and at least one constituent thin film having a compressive stress. The thin films forming the multi-layer assemblies may be disposed immediately adjacent to one another without the use of intermediate layers between the thin films.
Low stress polysilicon film and method for producing same
NASA Technical Reports Server (NTRS)
Heuer, Arthur H. (Inventor); Kahn, Harold (Inventor); Yang, Jie (Inventor)
2002-01-01
Multi-layer assemblies of polysilicon thin films having predetermined stress characteristics and techniques for forming such assemblies are disclosed. In particular, a multi-layer assembly of polysilicon thin film may be produced that has a stress level of zero, or substantially so. The multi-layer assemblies comprise at least one constituent thin film having a tensile stress and at least one constituent thin film having a compressive stress. The thin films forming the multi-layer assemblies may be disposed immediately adjacent to one another without the use of intermediate layers between the thin films.
Manganese containing layer for magnetic recording media
Lambeth, David N.; Lee, Li-Lien; Laughlin, David E.
1999-01-01
The present invention provides for a magnetic recording media incorporating Mn-containing layers between a substrate and a magnetic layer to provide media having increased coercivity and lower noise. The Mn-containing layer can be incorporated in a rotating, translating or stationary recording media to operate in conjunction with magnetic transducing heads for recording and reading of magnetic data, as well as other applications. The magnetic recording medium of the invention preferably includes a Co or Co alloy film magnetic layer, and Mn-containing layer, preferably comprised of VMn, TiMn, MnZn, CrMnMo, CrMnW, CrMnV, and CrMnTi, and most preferably a CrMn alloy, disposed between the substrate and the magnetic layer to promote an epitaxial crystalline structure in the magnetic layer. The medium can further include seed layers, preferably polycrystalline MgO for longitudinal media, underlayers, and intermediate layers. Underlayers and intermediate layers are comprised of materials having either an A2 structure or a B2-ordered crystalline structure disposed between the seed layer and the magnetic layer. Materials having an A2 structure are preferably Cr or Cr alloys, such as CrV, CrMo, CrW and CrTi. Materials having a B2-ordered structure having a lattice constant that is substantially comparable to that of Cr, such as those preferably selected from the group consisting of NiAl, AILCo, FeAl, FeTi, CoFe, CoTi, CoHf, CoZr, NiTi, CuBe, CuZn, A-LMn, AlRe, AgMg, and Al.sub.2 FeMn.sub.2, and is most preferably FeAl or NiAl.
Superconductive articles including cerium oxide layer
Wu, X.D.; Muenchausen, R.E.
1993-11-16
A ceramic superconductor comprising a metal oxide substrate, a ceramic high temperature superconductive material, and a intermediate layer of a material having a cubic crystal structure, said layer situated between the substrate and the superconductive material is provided, and a structure for supporting a ceramic superconducting material is provided, said structure comprising a metal oxide substrate, and a layer situated over the surface of the substrate to substantially inhibit interdiffusion between the substrate and a ceramic superconducting material deposited upon said structure. 7 figures.
Superconductive articles including cerium oxide layer
Wu, Xin D.; Muenchausen, Ross E.
1993-01-01
A ceramic superconductor comprising a metal oxide substrate, a ceramic high temperature superconductive material, and a intermediate layer of a material having a cubic crystal structure, said layer situated between the substrate and the superconductive material is provided, and a structure for supporting a ceramic superconducting material is provided, said structure comprising a metal oxide substrate, and a layer situated over the surface of the substrate to substantially inhibit interdiffusion between the substrate and a ceramic superconducting material deposited upon said structure.
Analysis of SnS2 hyperdoped with V proposed as efficient absorber material.
Seminovski, Yohanna; Palacios, Pablo; Wahnón, Perla
2014-10-01
Intermediate-band materials can improve the photovoltaic efficiency of solar cells through the absorption of two subband-gap photons that allow extra electron-hole pair formations. Previous theoretical and experimental findings support the proposal that the layered SnS2 compound, with a band-gap of around 2 eV, is a candidate for an intermediate-band material when it is doped with a specific transition-metal. In this work we characterize vanadium doped SnS2 using density functional theory at the dilution level experimentally found and including a dispersion correction combined with the site-occupancy-disorder method. In order to analyze the electronic characteristics that depend on geometry, two SnS2 polytypes partially substituted with vanadium in symmetry-adapted non-equivalent configurations were studied. In addition the magnetic configurations of vanadium in a SnS2 2H-polytype and its comparison with a 4H-polytype were also characterized. We demonstrate that a narrow intermediate-band is formed, when these dopant atoms are located in different layers. Our theoretical predictions confirm the recent experimental findings in which a paramagnetic intermediate-band material in a SnS2 2H-polytype with 10% vanadium concentration is obtained.
Structure of overheated metal clusters: MD simulation study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vorontsov, Alexander
2015-08-17
The structure of overheated metal clusters appeared in condensation process was studied by computer simulation techniques. It was found that clusters with size larger than several tens of atoms have three layers: core part, intermediate dense packing layer and a gas- like shell with low density. The change of the size and structure of these layers with the variation of internal energy and the size of cluster is discussed.
Partially Oxidized SnS2 Atomic Layers Achieving Efficient Visible-Light-Driven CO2 Reduction.
Jiao, Xingchen; Li, Xiaodong; Jin, Xiuyu; Sun, Yongfu; Xu, Jiaqi; Liang, Liang; Ju, Huanxin; Zhu, Junfa; Pan, Yang; Yan, Wensheng; Lin, Yue; Xie, Yi
2017-12-13
Unraveling the role of surface oxide on affecting its native metal disulfide's CO 2 photoreduction remains a grand challenge. Herein, we initially construct metal disulfide atomic layers and hence deliberately create oxidized domains on their surfaces. As an example, SnS 2 atomic layers with different oxidation degrees are successfully synthesized. In situ Fourier transform infrared spectroscopy spectra disclose the COOH* radical is the main intermediate, whereas density-functional-theory calculations reveal the COOH* formation is the rate-limiting step. The locally oxidized domains could serve as the highly catalytically active sites, which not only benefit for charge-carrier separation kinetics, verified by surface photovoltage spectra, but also result in electron localization on Sn atoms near the O atoms, thus lowering the activation energy barrier through stabilizing the COOH* intermediates. As a result, the mildly oxidized SnS 2 atomic layers exhibit the carbon monoxide formation rate of 12.28 μmol g -1 h -1 , roughly 2.3 and 2.6 times higher than those of the poorly oxidized SnS 2 atomic layers and the SnS 2 atomic layers under visible-light illumination. This work uncovers atomic-level insights into the correlation between oxidized sulfides and CO 2 reduction property, paving a new way for obtaining high-efficiency CO 2 photoreduction performances.
Margined winner-take-all: New learning rule for pattern recognition.
Fukushima, Kunihiko
2018-01-01
The neocognitron is a deep (multi-layered) convolutional neural network that can be trained to recognize visual patterns robustly. In the intermediate layers of the neocognitron, local features are extracted from input patterns. In the deepest layer, based on the features extracted in the intermediate layers, input patterns are classified into classes. A method called IntVec (interpolating-vector) is used for this purpose. This paper proposes a new learning rule called margined Winner-Take-All (mWTA) for training the deepest layer. Every time when a training pattern is presented during the learning, if the result of recognition by WTA (Winner-Take-All) is an error, a new cell is generated in the deepest layer. Here we put a certain amount of margin to the WTA. In other words, only during the learning, a certain amount of handicap is given to cells of classes other than that of the training vector, and the winner is chosen under this handicap. By introducing the margin to the WTA, we can generate a compact set of cells, with which a high recognition rate can be obtained with a small computational cost. The ability of this mWTA is demonstrated by computer simulation. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Miyake, Michihiro; Iwami, Makoto; Takeuchi, Mizue; Nishimoto, Shunsuke; Kameshima, Yoshikazu
2018-06-01
The electrochemical performance of layered Ni0.8Cu0.2/Ce0.8Gd0.2O1.9 (GDC) cermet anodes is investigated for intermediate-temperature solid oxide fuel cells (IT-SOFCs) at 600 °C using humidified (3% H2O) model syngas with a molar ratio of H2/CO = 3/2 as the fuel. From the results obtained, the electrochemical performance of the functionally graded multi-layered anodes is found to be superior to the mono-layered anodes. The test cell with a bi-layered anode consisting of 100 mass% Ni0.8Cu0.2/0 mass% GDC (10M/0E) and 70 mass% Ni0.8Cu0.2/30 mass% GDC (7M/3E) exhibits high power density. The test cell with a tri-layered anode consisting of 10M/0E, 7M/3E, and 50 mass% Ni0.8Cu0.2/50 mass% GDC (5M/5E) exhibits an even higher power density, suggesting that 10M/0E and 5M/5E layers contribute to the current collecting part and active part, respectively.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Song, Kok Wee; Koshelev, Alexei E.
Electronic nematicity plays an important role in iron-based superconductors. These materials have a layered structure and the theoretical description of their magnetic and nematic transitions has been well established in the two-dimensional approximation, i.e., when the layers can be treated independently. However, the interaction between iron layers mediated by electron tunneling may cause nontrivial three-dimensional behavior. Starting from the simplest model for orbital nematic in a single layer, we investigate the influence of interlayer tunneling on the bulk nematic order and a possible preemptive state where this order is only formed near the surface. In addition, we found that themore » interlayer tunneling suppresses the bulk nematicity, which makes favorable the formation of a surface nematic order above the bulk transition temperature. The purely electronic tunneling Hamiltonian, however, favors a nematic order parameter that alternates from layer to layer. The uniform bulk state typically observed experimentally may be stabilized by the coupling with the elastic lattice deformation. Depending on the strength of this coupling, we found three regimes: (i) surface nematic and alternating bulk order, (ii) surface nematic and uniform bulk order, and (iii) uniform bulk order without the intermediate surface phase. Lastly, the intermediate surface-nematic state may resolve the current controversy about the existence of a weak nematic transition in the compound BaFe 2As 2-xP x .« less
Surface nematic order in iron pnictides
NASA Astrophysics Data System (ADS)
Song, Kok Wee; Koshelev, Alexei E.
2016-09-01
Electronic nematicity plays an important role in iron-based superconductors. These materials have a layered structure and the theoretical description of their magnetic and nematic transitions has been well established in the two-dimensional approximation, i.e., when the layers can be treated independently. However, the interaction between iron layers mediated by electron tunneling may cause nontrivial three-dimensional behavior. Starting from the simplest model for orbital nematic in a single layer, we investigate the influence of interlayer tunneling on the bulk nematic order and a possible preemptive state where this order is only formed near the surface. We found that the interlayer tunneling suppresses the bulk nematicity, which makes favorable the formation of a surface nematic order above the bulk transition temperature. The purely electronic tunneling Hamiltonian, however, favors a nematic order parameter that alternates from layer to layer. The uniform bulk state typically observed experimentally may be stabilized by the coupling with the elastic lattice deformation. Depending on the strength of this coupling, we found three regimes: (i) surface nematic and alternating bulk order, (ii) surface nematic and uniform bulk order, and (iii) uniform bulk order without the intermediate surface phase. The intermediate surface-nematic state may resolve the current controversy about the existence of a weak nematic transition in the compound BaFe2As2 -xPx .
Independent Orbiter Assessment (IOA): Analysis of the pyrotechnics subsystem
NASA Technical Reports Server (NTRS)
Robinson, W. W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Pyrotechnics hardware. The IOA analysis process utilized available pyrotechnics hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.
Drainage fracture networks in elastic solids with internal fluid generation
NASA Astrophysics Data System (ADS)
Kobchenko, Maya; Hafver, Andreas; Jettestuen, Espen; Galland, Olivier; Renard, François; Meakin, Paul; Jamtveit, Bjørn; Dysthe, Dag K.
2013-06-01
Experiments in which CO2 gas was generated by the yeast fermentation of sugar in an elastic layer of gelatine gel confined between two glass plates are described and analyzed theoretically. The CO2 gas pressure causes the gel layer to fracture. The gas produced is drained on short length scales by diffusion and on long length scales by flow in a fracture network, which has topological properties that are intermediate between river networks and hierarchical-fracture networks. A simple model for the experimental system with two parameters that characterize the disorder and the intermediate (river-fracture) topology of the network was developed and the results of the model were compared with the experimental results.
Studies of the Initial Stages of Epitaxial Growth of Germanium on Silicon
NASA Astrophysics Data System (ADS)
Krishnamurthy, Mohan
The epitaxial growth of ultra-thin films (< 1nm thick) of Ge on Si(100) has been studied in -situ in an Ultra High Vacuum-Scanning Transmission Electron Microscope. Ge was deposited on clean Si(100) using molecular beam techniques to study two types of growth processes, Molecular Beam Epitaxy (MBE) and Solid Phase MBE. Ge grows in the Stranski-Krastanov growth mode, forming islands after initial layer growth. This islanding transition has been studied with high spatial resolution biassed Secondary Electron Imaging and Auger spectroscopy and imaging. Ex -situ Transmission Electron Microscopy (TEM) and Reflection High Energy Diffraction (RHEED) were also used to characterize the transition. The islanding process and its subsequent evolution was monitored with the help of island size distributions, sensitive to islands above 2nm in size. The studies indicate that Ge forms islands in equilibrium with a 3 monolayer (ML) thick intermediate layer. These islands may initially grow coherently strained (dislocation free) with radii usually below 10nm under the conditions. The strain in these islands reduces the adatom sticking coefficient and strongly influences the microstructural evolution. The intermediate layer may grow metastably under certain conditions to as much as 7 ML before collapsing to its equilibrium form. The influence of three types of adatom sinks--strained islands, dislocated islands and contaminant particles have been studied. The contaminant particles are the strongest sinks, followed by dislocated islands and strained islands. Stepped (vicinal) surfaces (1^circ and 5 ^circ toward {110 }) had no significant influence possibly due to the steps being weak adatom sinks. The coarsening of Ge islands does not follow the Ostwald ripening model at the early stages and is influenced by the supersaturation in the intermediate layer and the strain in the coherent islands. A novel mechanism has been observed, where the larger (dislocated) islands grow at the expense of the unstable intermediate layer while the distribution of smaller (strained) islands is constant. This is possibly due to the lower sticking coefficient at the strained islands.
Altered expression of hyaluronan, HAS1-2, and HYAL1-2 in oral lichen planus.
Siponen, Maria; Kullaa, Arja; Nieminen, Pentti; Salo, Tuula; Pasonen-Seppänen, Sanna
2015-07-01
Oral lichen planus (OLP) is an immune-mediated mucosal disease of unclear etiology and of unresolved pathogenesis. Hyaluronan (HA) is an extracellular matrix glycosaminoglycan involved in inflammation and tumor progression. However, its presence in OLP has not been reported. We therefore aimed to study the immunohistochemical expression of HA, its receptor CD44, hyaluronan synthases (HAS1-3), and hyaluronidases (HYAL1-2) in OLP. The presence of HA, CD44, HAS1-3, and HYAL1-2 was studied by immunohistochemical methods in 55 OLP and 23 control oral mucosal specimens (CTR). The localization, intensity, and differences of the epithelial expression between OLP and CTRs were analyzed. HA and CD44 were found on cell membranes in the epithelial basal and intermediate layers in CTR and OLP specimens. The HA staining intensity was stronger in the basal layer of the epithelium in OLP than in CTRs (P < 0.001). HAS1 (P = 0.001) and HAS2 (P < 0.001) showed stronger staining in the basal and weaker staining in the superficial (P < 0.001) epithelial layers in OLP than in CTRs. The immunostaining of HAS3 was low in both OLP and CTRs. Positive HYAL1 and HYAL2 staining were mainly found in the basal and intermediate epithelial layers, and their intensities were significantly increased in OLP, except HYAL 2 in the intermediate epithelial layer. HA, HAS1-2, and HYAL1-2 have altered expression in OLP compared to CTRs and may therefore have a role in OLP pathogenesis. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Ren, Xuefeng; Yu, Libo; Li, Zhen; Song, Hai; Wang, Qingyun
2018-01-01
We build CdSe quantum dots (QDs) sensitized TiO2 NT solar cells (CdSe/TiO2 solar cells) by successive ionic layer adsorption reaction (SILAR) method on free-standing translucent TiO2 nanotube (NT) film. The best power conversion efficiency (PCE) 0.74% is obtained with CdSe/TiO2 NT solar cells, however, it is very low. Hence, we introduced the CdS QDs layer located between CdSe QDs and TiO2 NT to achieve an enhanced photovoltaic performance. The J-V test results indicated that the insert of CdS intermediate layer yield a significant improvement of PCE to 2.52%. Combining experimental and theoretical analysis, we find that the effects caused by a translucent TiO2 nanotube film, a better lattices match between CdS and TiO2, and a new formed stepwise band edges structure not only improve the light harvesting efficiency but also increase the driving force of electrons, leading to the improvement of photovoltaic performance.
Study of low-defect and strain-relaxed GeSn growth via reduced pressure CVD in H2 and N2 carrier gas
NASA Astrophysics Data System (ADS)
Margetis, J.; Mosleh, A.; Al-Kabi, S.; Ghetmiri, S. A.; Du, W.; Dou, W.; Benamara, M.; Li, B.; Mortazavi, M.; Naseem, H. A.; Yu, S.-Q.; Tolle, J.
2017-04-01
High quality, thick (up to 1.1 μm), strain relaxed GeSn alloys were grown on Ge-buffered Si (1 0 0) in an ASM Epsilon® chemical vapor deposition system using SnCl4 and low-cost commercial GeH4 precursors. The significance of surface chemistry in regards to growth rate and Sn-incorporation is discussed by comparing growth kinetics data in H2 and N2 carrier gas. The role of carrier gas is also explored in the suppression of Sn surface segregation and evolution of layer composition and strain profiles via secondary ion mass spectrometry and X-ray diffraction. Transmission electron microscopy revealed the spontaneous compositional splitting and formation of a thin intermediate layer in which dislocations are pinned. This intermediate layer enables the growth of a thick, strain relaxed, and defect-free epitaxial layer on its top. Last, we present photoluminescence results which indicate that both N2 and H2 growth methods produce optoelectronic device quality material.
Potentiometric surfaces of the intermediate aquifer system, west-central Florida, September 2000
Duerr, A.D.
2001-01-01
The intermediate aquifer system underlies a 5,000-square-mile area within the Southwest Florida Water Management District including De Soto, Sarasota, Hardee, Manatee, and parts of Charlotte, Hillsborough, Highlands, Polk, and Lee Counties. The intermediate aquifer system is overlain by the surficial aquifer system and is underlain by the Floridan aquifer system. The intermediate aquifer system consists of layers of sand, shell, clay, calcareous clay, limestone, and dolomite of the Tamiami Formation and Hawthorn Group of Oligocene to Pleistocene age (Wingard and others, 1995). The intermediate aquifer system contains one or more water-bearing units separated by discontinuous confining units. The intermediate aquifer system is the principal source of potable water in the southwestern part of the study area and is widely used as a source of water where wells are open to the intermediate aquifer system or to both the intermediate and Floridan aquifer systems. Yields of individual wells open to the intermediate aquifer system vary from a few gallons to several hundred gallons per minute. The volume of water withdrawn from the intermediate aquifer system is considerably less than that withdrawn from the Floridan aquifer system in the study area (Duerr and others, 1988).
Zou, Jie; Lambeth, David N.; Laughlin, David E.
2002-01-01
The present invention provides a magnetic recording media incorporating Zn containing layers in close proximity to a magnetic layer to provide media having increased coercivity and lower noise. The Zn containing layer can be incorporated in a rotating, translating or stationary recording media to operate in conjunction with magnetic transducing heads for recording and reading of magnetic data, as well as other applications. The magnetic recording medium of the invention preferably includes a Co or Co alloy film magnetic layer, underlayer structures to promote epitaxial crystalline structure in the magnetic layer, and a Zn containing layer to promote isolation between the magnetic grains. The medium can further include seed layers, underlayers, intermediate layers, and overlayers. The process of manufacture includes promoting diffusion of Zn to the magnetic layer grain boundaries.
NASA Astrophysics Data System (ADS)
Estep, J. D.; Reece, R.; Kardell, D. A.; Christeson, G. L.; Carlson, R. L.
2017-12-01
Seismic layer 2A, the uppermost igneous portion of oceanic crust, is commonly used to refer to the seismic velocities of upper crust that are bounded below by a steep vertical velocity gradient. Layer 2A velocities are known to increase with crustal age, from 2.5 km/s in crust <1 Ma to 4.5-5 km/s in crust >15 Ma. Thickness of layer 2A has been shown to increase by a factor of 2 within 1 Ma at fast spreading ridges and then remain relatively constant, while layer 2A maintains a fairly consistent thickness, irrespective of age, at slow-intermediate spreading ridges. Layer 2A thickness and velocity evolution studies to date have been largely focused on young oceanic crust very proximal to a spreading center with little investigation of changes (or lack thereof) that occur at crustal ages >10 Ma. We utilize a multichannel seismic dataset collected at 30° S in the western South Atlantic that continuously images 0 - 70 Ma oceanic crust along a single flowline generated at the slow-intermediate spreading Mid-Atlantic Ridge. We follow the methods of previous studies by processing the data to image the layer 2A event, which is then used for calculating thickness. 1D travel time forward modeling at regularly spaced age intervals across the transect provides for the conversion of time to depth thickness, and for determining the evolution of velocities with age. Our results show layer 2A in 20 Ma crust is roughly double the thickness of that in crust 0-5 Ma (830 vs. 440 m), but thickness does not appear to change beyond 20 Ma. The layer 2A event is readily observable in crust 0-50 Ma, is nearly completely absent in crust 50-65 Ma, and then reappears with anomalously high amplitude and lateral continuity in crust 65-70 Ma. Our results suggest that layer 2A thickens with age at the slow-intermediate spreading southern Mid-Atlantic Ridge, and that layer 2A either continues to evolve at the older crustal ages, well beyond the expected 10-15 Ma "mature age", or that external factors have altered the crust at 65-70 Ma. The proximity and thermal influence of the Rio Grande Rise might explain the anomalous appearance of the layer 2A event at the older ages of crust for the study.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jiang, Zhenyu, E-mail: jiangzhenyu1201@hotmail.com, E-mail: jianxu@engr.psu.edu; Liu, Yan; Mo, Chen
In an attempt to suppress the dark current, the barrier layer engineer for solution-processed PbSe colloidal quantum-dot (CQD) photodetectors has been investigated in the present study. It was found that the dark current can be significantly suppressed by implementing two types of carrier blocking layers, namely, hole blocking layer and electron blocking layer, sandwiched in between two active PbSe CQD layers. Meanwhile no adverse impact has been observed for the photo current. Our study suggests that this improvement resides on the transport pathway created via carrier recombination at intermediate layer, which provides wide implications for the suppression of dark currentmore » for infrared photodetectors.« less
El Faiz, Abdelouahed; Duponnois, Robin; Winterton, Peter; Ouhammou, Ahmed; Meddich, Abdelillah; Boularbah, Ali; Hafidi, Mohamed
2015-01-01
Canna indica L. (CiL) was used here in phytoremediation of mining soils. Our work evaluated the effect of AMF (i) on the growth and (ii) on the uptake of heavy metals (HM). The tests were conducted in the greenhouse on mining substrates collected from the Kettara mine (Morocco). The mine soil was amended by different proportions of agricultural soil and compost and then inoculated with two isolates of AMF (IN1) and (IN2) of different origins. After six months of culture, the results show that on mining soils (100%) only AMF (IN2) was able to colonize the roots of CiL with a frequency of 40±7% and an intensity of 6.5±1.5%. Also, the lowest values of shoot and root dry biomass are obtained on these mining soils with respectively 0.30 g and 0.27 g. In contrast, the accumulation of HM was higher and reached more than 50% of that contained in the mining soils, the highest values with 138 mg kg(-1) Cu2+, Zn2+ 270 mg kg(-1) and 1.38 mg kg(-1) Cd was recorded. These results indicate that the colonization of CiL roots by AMF (IN2) could significantly improve its potential to be used in phytoremediation of polluted soil.
Lightweight flywheel containment
Smith, James R.
2001-01-01
A lightweight flywheel containment composed of a combination of layers of various material which absorb the energy of a flywheel structural failure. The various layers of material act as a vacuum barrier, momentum spreader, energy absorber, and reaction plate. The flywheel containment structure has been experimentally demonstrated to contain carbon fiber fragments with a velocity of 1,000 m/s and has an aerial density of less than 6.5 g/square centimeters. The flywheel containment, may for example, be composed of an inner high toughness structural layer, and energy absorbing layer, and an outer support layer. Optionally, a layer of impedance matching material may be utilized intermediate the flywheel rotor and the inner high toughness layer.
Lightweight flywheel containment
Smith, James R.
2004-06-29
A lightweight flywheel containment composed of a combination of layers of various material which absorb the energy of a flywheel structural failure. The various layers of material act as a vacuum barrier, momentum spreader, energy absorber, and reaction plate. The flywheel containment structure has been experimentally demonstrated to contain carbon fiber fragments with a velocity of 1,000 m/s and has an aerial density of less than 6.5 g/square centimeters. The flywheel containment, may for example, be composed of an inner high toughness structural layer, and energy absorbing layer, and an outer support layer. Optionally, a layer of impedance matching material may be utilized intermediate the flywheel rotor and the inner high toughness layer.
NASA Astrophysics Data System (ADS)
Krumhansl, Kira A.; Head, Erica J. H.; Pepin, Pierre; Plourde, Stéphane; Record, Nicholas R.; Runge, Jeffrey A.; Johnson, Catherine L.
2018-03-01
Copepods of the genus Calanus play a critical trophic role in the North Atlantic ecosystems, where they serve as an important source of energy-rich food for fish and marine mammals, including the endangered North Atlantic right whale. As a strategy for coping with unfavorable near-surface conditions, Calanus enter diapause and migrate to deep water in late summer and fall after feeding and accumulating lipid stores in spring and summer. In order to assess the most important physical drivers of vertical distribution of diapausing Calanus, we synthesized existing depth-stratified abundance data of Calanus finmarchicus and Calanus hyperboreus from the Northwest Atlantic continental shelf and slope regions, spanning Newfoundland in the northeast to the Gulf of Maine in the southwest. Bottom depth strongly constrained the depth and shape of vertical distributions, with distributions becoming deeper and less compact as bottom depth increased. Diapausing Calanus, observed across a broad range of temperature (T) and in-situ density (σ) conditions (T = -1.0 to 14.4 °C, σ = 25.3-28.1 kg m-3), tended to distribute at depths with the coldest temperatures locally available. Over the shelf, diapausing Calanus in the GOM and SS generally did not have access to temperatures considered optimal for diapause (<5 °C), in many cases occurring at temperatures well above this threshold. Diapausing Calanus in both habitats were most commonly below the Cold Intermediate Layer (CIL), a feature formed through wind-driven mixing during the winter, but this effect was more obvious over the shelf than in slope waters. Our analysis highlights key differences in the vertical distributions of diapausing Calanus over the shelf vs. the slope, having regional implications for ecological dynamics and population persistence in the face of warming temperatures. In general, understanding factors that influence vertical distributions of diapausing Calanus will allow us to more accurately predict how the environmental conditions they encounter while overwintering may shift during climate change, which has implications for survival through diapause, and consequently, shelf-wide population dynamics.
Jovian meterology: Large-scale moist convection without a lower boundary
NASA Technical Reports Server (NTRS)
Gierasch, P. J.
1975-01-01
It is proposed that Jupiter's cloud bands represent large scale convection whose character is determined by the phase change of water at a level where the temperature is about 275K. It is argued that there are three important layers in the atmosphere: a tropopause layer where emission to space occurs; an intermediate layer between the tropopause and the water cloud base; and the deep layer below the water cloud. All arguments are only semi-quantitative. It is pointed out that these ingredients are essential to Jovian meteorology.
Independent Orbiter Assessment (IOA): Analysis of the communication and tracking subsystem
NASA Technical Reports Server (NTRS)
Gardner, J. R.; Robinson, W. M.; Trahan, W. H.; Daley, E. S.; Long, W. C.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Communication and Tracking hardware. The IOA analysis process utilized available Communication and Tracking hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.
Multiwall thermal protection system
NASA Technical Reports Server (NTRS)
Jackson, L. R. (Inventor)
1982-01-01
Multiwall insulating sandwich panels are provided for thermal protection of hypervelocity vehicles and other enclosures. In one embodiment, the multiwall panels are formed of alternate layers of dimpled and flat metal (titanium alloy) foil sheets and beaded scarfed edge seals to provide enclosure thermal protection up to 1000 F. An additional embodiment employs an intermediate fibrous insulation for the sandwich panel to provide thermal protection up to 2000 F. A third embodiment employs a silicide coated columbium waffle as the outer panel skin and fibrous layered intermediate protection for thermal environment protection up to 2500 F. The use of multiple panels on an enclosure facilitate repair and refurbishment of the thermal protection system due to the simple support provided by the tab and clip attachment for the panels.
Intermediate type excitons in Schottky barriers of A3B6 layer semiconductors and UV photodetectors
NASA Astrophysics Data System (ADS)
Alekperov, O. Z.; Guseinov, N. M.; Nadjafov, A. I.
2006-09-01
Photoelectric and photovoltaic spectra of Schottky barrier (SB) structures of InSe, GaSe and GaS layered semiconductors (LS) are investigated at quantum energies from the band edge excitons of corresponding materials up to 6.5eV. Spectral dependences of photoconductivity (PC) of photo resistors and barrier structures are strongly different at the quantum energies corresponding to the intermediate type excitons (ITE) observed in these semiconductors. It was suggested that high UV photoconductivity of A3B6 LS is due to existence of high mobility light carriers in the depth of the band structure. It is shown that SB of semitransparent Au-InSe is high sensitive photo detector in UV region of spectra.
Skieresz-Szewczyk, Kinga; Jackowiak, Hanna; Ratajczak, Marlena
2014-12-01
The previous histological studies of the lingual mucosa in birds characterized two types of keratinized epithelium, i.e. orthokeratinized and parakeratinized. These epithelia are composed of three layers: basal, intermediate and keratinized. The present study showed detailed ultrastructural features of cells in particular layers of two types of keratinized epithelia on the tongue in the domestic duck and defined structural differences. TEM observations showed a gradual reduction in cell organelles in the following layers, at increasing amounts of keratin fibers. The characteristic feature of the ortho- and parakeratinized epithelium is the presence of sub-layers in the intermediate layer, i.e. the upper and lower part, which results from the different shape of cell nuclei and dye affinity of the cytoplasm. The keratinized layer of ortho- and parakeratinized epithelium is built of two types of cells such as electron dark and light cells, which undergo exfoliation. The basic difference between the keratinized epithelia is the presence of flattened cell nuclei in the keratinized layer of the parakeratinized epithelium. The differentiating feature is also an arrangement of keratin fibers in the cell cytoplasm of the keratinized layer. The analysis of the thickness of the epithelium and the keratinized layer, indicated differences between keratinized epithelia, which result from two variants of performing protective functions, either through a thick keratinized layer or by a higher epithelium. Differences in the ultrastructure of the ortho- and parakeratinized epithelium are associated with mechanical functions of the epithelium resulting from different forces acting on the tongue during feeding activities. Copyright © 2014 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gu, Jing; Yan, Yong; Young, James
2017-05-01
We demonstrate that by employing a hybrid molecular/semiconductor interface with atomic layer deposited (ALD) TiO2 as an intermediate layer, a robust and corrosion resistant GaInP2-TiO2-cobaltoxime-TiO2 photocathode can be operated in alkaline media (pH =13).
M&A For Lithography Of Sparse Arrays Of Sub-Micrometer Features
Brueck, Steven R.J.; Chen, Xiaolan; Zaidi, Saleem; Devine, Daniel J.
1998-06-02
Methods and apparatuses are disclosed for the exposure of sparse hole and/or mesa arrays with line:space ratios of 1:3 or greater and sub-micrometer hole and/or mesa diameters in a layer of photosensitive material atop a layered material. Methods disclosed include: double exposure interferometric lithography pairs in which only those areas near the overlapping maxima of each single-period exposure pair receive a clearing exposure dose; double interferometric lithography exposure pairs with additional processing steps to transfer the array from a first single-period interferometric lithography exposure pair into an intermediate mask layer and a second single-period interferometric lithography exposure to further select a subset of the first array of holes; a double exposure of a single period interferometric lithography exposure pair to define a dense array of sub-micrometer holes and an optical lithography exposure in which only those holes near maxima of both exposures receive a clearing exposure dose; combination of a single-period interferometric exposure pair, processing to transfer resulting dense array of sub-micrometer holes into an intermediate etch mask, and an optical lithography exposure to select a subset of initial array to form a sparse array; combination of an optical exposure, transfer of exposure pattern into an intermediate mask layer, and a single-period interferometric lithography exposure pair; three-beam interferometric exposure pairs to form sparse arrays of sub-micrometer holes; five- and four-beam interferometric exposures to form a sparse array of sub-micrometer holes in a single exposure. Apparatuses disclosed include arrangements for the three-beam, five-beam and four-beam interferometric exposures.
Surface nematic order in iron pnictides
Song, Kok Wee; Koshelev, Alexei E.
2016-09-09
Electronic nematicity plays an important role in iron-based superconductors. These materials have a layered structure and the theoretical description of their magnetic and nematic transitions has been well established in the two-dimensional approximation, i.e., when the layers can be treated independently. However, the interaction between iron layers mediated by electron tunneling may cause nontrivial three-dimensional behavior. Starting from the simplest model for orbital nematic in a single layer, we investigate the influence of interlayer tunneling on the bulk nematic order and a possible preemptive state where this order is only formed near the surface. In addition, we found that themore » interlayer tunneling suppresses the bulk nematicity, which makes favorable the formation of a surface nematic order above the bulk transition temperature. The purely electronic tunneling Hamiltonian, however, favors a nematic order parameter that alternates from layer to layer. The uniform bulk state typically observed experimentally may be stabilized by the coupling with the elastic lattice deformation. Depending on the strength of this coupling, we found three regimes: (i) surface nematic and alternating bulk order, (ii) surface nematic and uniform bulk order, and (iii) uniform bulk order without the intermediate surface phase. Lastly, the intermediate surface-nematic state may resolve the current controversy about the existence of a weak nematic transition in the compound BaFe 2As 2-xP x .« less
2013-04-01
which freezes ions into well defined structures and coats them with an inert layer of weakly bound adducts. These cold aggregates were then...evaporation of the cryogenic solvent. Instrument development. Cryogenic ion processing. Cold ion spectroscopy. Trapped reaction intermediates U U U...spectrometer. The key advance incorporated into this instrument is the introduction of a cryogenic (10K) ion processing stage, where ions can be frozen
Fluorescence intensity positivity classification of Hep-2 cells images using fuzzy logic
NASA Astrophysics Data System (ADS)
Sazali, Dayang Farzana Abang; Janier, Josefina Barnachea; May, Zazilah Bt.
2014-10-01
Indirect Immunofluorescence (IIF) is a good standard used for antinuclear autoantibody (ANA) test using Hep-2 cells to determine specific diseases. Different classifier algorithm methods have been proposed in previous works however, there still no valid set as a standard to classify the fluorescence intensity. This paper presents the use of fuzzy logic to classify the fluorescence intensity and to determine the positivity of the Hep-2 cell serum samples. The fuzzy algorithm involves the image pre-processing by filtering the noises and smoothen the image, converting the red, green and blue (RGB) color space of images to luminosity layer, chromaticity layer "a" and "b" (LAB) color space where the mean value of the lightness and chromaticity layer "a" was extracted and classified by using fuzzy logic algorithm based on the standard score ranges of antinuclear autoantibody (ANA) fluorescence intensity. Using 100 data sets of positive and intermediate fluorescence intensity for testing the performance measurements, the fuzzy logic obtained an accuracy of intermediate and positive class as 85% and 87% respectively.
NASA Astrophysics Data System (ADS)
Shri Prakash, B.; Pavitra, R.; Senthil Kumar, S.; Aruna, S. T.
2018-03-01
Lowering of operation temperature has become one of the primary goals of solid oxide fuel (SOFC) research as reduced temperature improves the prospects for widespread commercialization of this energy system. Reduced operational temperature also mitigates the issues associated with high temperature SOFCs and paves way not only for the large scale stationary power generation but also makes SOFCs viable for portable and transport applications. However, there are issues with electrolyte and cathode materials at low temperatures, individually as well as in association with other components, which makes the performance of the SOFCs less satisfactory than expected at lowered temperatures. Bi-layering of electrolytes and impregnation of cathodes have emerged as two important strategies to overcome these issues and achieve higher performance at low temperatures. This review article provides the perspective on the strategy of bi-layering of electrolyte to achieve the desired high performance from SOFC at low to intermediate temperatures.
Weyand, J.D.; Woods, R.W.; DeYoung, D.H.; Ray, S.P.
1985-02-19
An inert electrode connection is disclosed wherein a layer of inert electrode material is bonded to a layer of conductive material by providing at least one intermediate layer of material therebetween comprising a predetermined ratio of inert material to conductive material. In a preferred embodiment, the connection is formed by placing in a die a layer of powdered inert material, at least one layer of a mixture of powdered inert material and conductive material, and a layer of powdered conductive material. The connection is then formed by pressing the material at 15,000--20,000 psi to form a powder compact and then densifying the powder compact in an inert or reducing atmosphere at a temperature of 1,200--1,500 C. 5 figs.
Functionally graded alumina-based thin film systems
Moore, John J.; Zhong, Dalong
2006-08-29
The present invention provides coating systems that minimize thermal and residual stresses to create a fatigue- and soldering-resistant coating for aluminum die casting dies. The coating systems include at least three layers. The outer layer is an alumina- or boro-carbide-based outer layer that has superior non-wettability characteristics with molten aluminum coupled with oxidation and wear resistance. A functionally-graded intermediate layer or "interlayer" enhances the erosive wear, toughness, and corrosion resistance of the die. A thin adhesion layer of reactive metal is used between the die substrate and the interlayer to increase adhesion of the coating system to the die surface.
[Architectural ultrastructure of the human urinary transitional epithelium].
Takayama, H; Konishi, T
1984-07-01
Human urinary bladder mucosa, confirmed to be normal by cystoscopic, histologic and bacteriologic examination, were obtained from four patients at prostatectomy and from two patients at an anti-VUR procedure. The luminal surface and the three dimensional architecture of the bladder mucosa were observed by scanning electron microscopy (SEM) after cryofracture of specimen and by transmission electron microscopy (TEM). The epithelium consists of superficial, intermediate and basal cells, and SEM and TEM showed that it was stratified. Intermediate cells reached the basal lamina by slender cytoplasmic processes but superficial cells were not directly in contact with the basal lamina. No pleomorphic or long microvilli were observed but short microvilli or granular protrusions were sparsely seen on the luminal surface of superficial cells. SEM of cryofractured surfaces revealed that cells from each cell layer were in contact with cellular junctions such as ridges, plicated projections and septum-like walls. Their junctions were more complicated with increasing depth of the cell layer. No pleomorphic or long microvilli were observed on any cell surface of the intermediate or basal cell layer. Under TEM, however, these junctional structures of ridges, plicated projections and septal walls appeared to be microvilli under TEM. Microvilli-like structures on TEM, therefore, have to be carefully distinguished from real microvilli. Careful observation is required when the presence of cells covered with microvilli is described as a sign of malignancy.
40 CFR 265.1032 - Standards: Process vents.
Code of Federal Regulations, 2010 CFR
2010-07-01
... owner or operator of a fa-cil-ity with process vents associated with distillation, fractionation, thin-film evaporation, solvent extraction or -air or steam stripping operations man-aging haz-ard-ous wastes...
40 CFR 265.1032 - Standards: Process vents.
Code of Federal Regulations, 2011 CFR
2011-07-01
... owner or operator of a fa-cil-ity with process vents associated with distillation, fractionation, thin-film evaporation, solvent extraction or -air or steam stripping operations man-aging haz-ard-ous wastes...
NASA Astrophysics Data System (ADS)
Filippov, V. P.; Lauer, Yu. A.; Goloborodko, P. G.; Polyakov, A. M.
2016-12-01
The phase composition of the intermediate oxide layers formed on elements of steel structures at different positions relative to the sea water of the Black Sea near Sochi are investigated. The differences of the phase composition of these oxide layers are shown, depending on the location of the design details in relation to the sea and the abundancies of certain types of oxides in the studied layers are discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Radha, S.; Milius, Wolfgang; Breu, Josef, E-mail: josef.breu@uni-bayreuth.de
2013-08-15
The thiosulfate-intercalated layered double hydroxide of Zn and Al undergoes reversible hydration with a variation in the relative humidity of the ambient. The hydrated and dehydrated phases, which represent the end members of the hydration cycle, both adopt the structure of the 3R{sub 1} polytype. In the intermediate range of relative humidity values (40–60%), the hydrated and dehydrated phases coexist. The end members of the hydration cycle adopt the structure of the same polytype, and vary only in their basal spacings. This points to the possibility that all the intermediate phases have a kinetic origin. - Graphical abstract: Basal spacingmore » evolution of the thiosulfate ion intercalated [Zn–Al] LDH during one complete hydration–dehydration cycle as a function of relative humidity. Display Omitted - Highlights: • Thiosulfate intercalated [Zn–Al] LDHs were synthesized by co-precipitation. • The LDH exhibits reversible hydration with variation in humidity. • Both the end members of the hydration cycle adopt the same polytype structure. • The interstratified intermediates observed are kinetic in origin.« less
NASA Astrophysics Data System (ADS)
Schulz, Tobias; Weinmüller, Christian; Nabavi, Majid; Poulikakos, Dimos
A single cell micro-direct methanol fuel cell (micro-DMFC) was investigated using electrochemical impedance spectroscopy. The electrodes consisted of thin, flexible polymer (SU8) film microchannel structures fabricated in-house using microfabrication techniques. AC impedance spectroscopy was used to separate contributions to the overall cell polarization from the anode, cathode and membrane. A clear distinction between the different electrochemical phenomena occurring in the micro-DMFC, especially the distinction between double layer charging and Faradaic reactions was shown. The effect of fuel flow rate, temperature, and anode flow channel structure on the impedance of the electrode reactions and membrane/electrode double layer charging were investigated. Analysis of impedance data revealed that the performance of the test cell was largely limited by the presence of intermediate carbon monoxide in the anode reaction. Higher temperatures increase cell performance by enabling intermediate CO to be oxidized at much higher rates. The results also revealed that serpentine anode flow microchannels show a lower tendency to intermediate CO coverage and a more stable cell behavior than parallel microchannels.
Interconnects for intermediate temperature solid oxide fuel cells
NASA Astrophysics Data System (ADS)
Huang, Wenhua
Presently, one of the principal goals of solid oxide fuel cells (SOFCs) research is to reduce the stack operating temperature to between 600 and 800°C. However, one of the principal technological barriers is the non-availability of a suitable material satisfying all of the stability requirements for the interconnect. In this work two approaches for intermediate temperature SOFC interconnects have been explored. The first approach comprises an interconnect consisting of a bi-layer structure, a p-type oxide (La0.96Sr0.08MnO 2.001/LSM) layer exposed to a cathodic environment, and an n-type oxide (Y0.08Sr0.88Ti0.95Al0.05O 3-delta/YSTA) layer exposed to anodic conditions. Theoretical analysis based on the bi-layer structure has established design criteria to implement this approach. The analysis shows that the interfacial oxygen partial pressure, which determines the interconnect stability, is independent of the electronic conductivities of both layers but dependent on the oxygen ion layer interconnects, the oxygen ion conductivities of LSM and YSTA were measured as a function of temperature and oxygen partial pressure. Based on the measured data, it has been determined that if the thickness of YSTA layer is around 0.1cm, the thickness of LSM layer should be around 0.6 mum in order to maintain the stability of LSM. In a second approach, a less expensive stainless steel interconnect has been studied. However, one of the major concerns associated with the use of metallic interconnects is the development of a semi-conducting or insulating oxide scale and chromium volatility during extended exposure to the SOFC operating environment. Dense and well adhered Mn-Cu spinet oxide coatings were successfully deposited on stainless steel by an electrophoretic deposition (EPD) technique. It was found that the Mn-Cu-O coating significantly reduced the oxidation rate of the stainless steel and the volatility of chromium. The area specific resistance (ASR) of coated Crofer 22 APU is expected to he around 1.2x10 -2Ocm2 after exposure to air at 800°C for 50000 hours. This demonstrates that Crofer 22 APU with CuMn1.8O 4 coating deposited by EPD is suitable for application as interconnects in intermediate temperature SOFCs.
Super-Planckian Thermophotovoltaics Without Vacuum Gaps
NASA Astrophysics Data System (ADS)
Mirmoosa, M. S.; Biehs, S.-A.; Simovski, C. R.
2017-11-01
We introduce the concept of a thermophotovoltaic system whose emitter is separated from the photovoltaic cell by an intermediate thick slab of gallium arsenide. Owing to the engineered structure of the emitter (a multilayer structure of negative- and positive-ɛ layers) together with a high refractiveindex and transparency of the intermediate slab, we achieve a super-Planckian and frequency-selective spectrum of radiative heat transfer which is desirable for the efficient performance of thermophotovoltaic systems.
Independent Orbiter Assessment (IOA): Analysis of the reaction control system, volume 3
NASA Technical Reports Server (NTRS)
Burkemper, V. J.; Haufler, W. A.; Odonnell, R. A.; Paul, D. J.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results for the Reaction Control System (RCS). The RCS is situated in three independent modules, one forward in the orbiter nose and one in each OMS/RCS pod. Each RCS module consists of the following subsystems: Helium Pressurization Subsystem; Propellant Storage and Distribution Subsystem; Thruster Subsystem; and Electrical Power Distribution and Control Subsystem. Volume 3 continues the presentation of IOA analysis worksheets and the potential critical items list.
Independent Orbiter Assessment (IOA): Analysis of the crew equipment subsystem
NASA Technical Reports Server (NTRS)
Sinclair, Susan; Graham, L.; Richard, Bill; Saxon, H.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical (PCIs) items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The independent analysis results coresponding to the Orbiter crew equipment hardware are documented. The IOA analysis process utilized available crew equipment hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode. Of the 352 failure modes analyzed, 78 were determined to be PCIs.
Heterogeneous integration based on low-temperature bonding for advanced optoelectronic devices
NASA Astrophysics Data System (ADS)
Higurashi, Eiji
2018-04-01
Heterogeneous integration is an attractive approach to manufacturing future optoelectronic devices. Recent progress in low-temperature bonding techniques such as plasma activation bonding (PAB) and surface-activated bonding (SAB) enables a new approach to integrating dissimilar materials for a wide range of photonics applications. In this paper, low-temperature direct bonding and intermediate layer bonding techniques are focused, and their state-of-the-art applications in optoelectronic devices are reviewed. First, we describe the room-temperature direct bonding of Ge/Ge and Ge/Si wafers for photodetectors and of GaAs/SiC wafers for high-power semiconductor lasers. Then, we describe low-temperature intermediate layer bonding using Au and lead-free Sn-3.0Ag-0.5Cu solders for optical sensors and MEMS packaging.
Spectral ellipsometry as a method for characterization of nanosized films with ferromagnetic layers
NASA Astrophysics Data System (ADS)
Hashim, H.; Singkh, S. P.; Panina, L. V.; Pudonin, F. A.; Sherstnev, I. A.; Podgornaya, S. V.; Shpetnyi, I. A.; Beklemisheva, A. V.
2017-11-01
Nanosized films with ferromagnetic layers are widely used in nanoelectronics, sensor systems and telecommunications. Their properties may strongly differ from those of bulk materials that is on account of interfaces, intermediate layers and diffusion. In the present work, spectral ellipsometry and magnetooptical methods are adapted for characterization of the optical parameters and magnetization processes in two- and three-layer Cr/NiFe, Al/NiFe and Cr(Al)/Ge/NiFe films onto a sitall substrate for various thicknesses of Cr and Al layers. At a layer thickness below 20 nm, the complex refractive coefficients depend pronouncedly on the thickness. In two-layer films, remagnetization changes weakly over a thickness of the top layer, but the coercive force in three-layer films increases by more than twice upon remagnetization, while increasing the top layer thickness from 4 to 20 nm.
MEMS based pyroelectric thermal energy harvester
Hunter, Scott R; Datskos, Panagiotis G
2013-08-27
A pyroelectric thermal energy harvesting apparatus for generating an electric current includes a cantilevered layered pyroelectric capacitor extending between a first surface and a second surface, where the first surface includes a temperature difference from the second surface. The layered pyroelectric capacitor includes a conductive, bimetal top electrode layer, an intermediate pyroelectric dielectric layer and a conductive bottom electrode layer. In addition, a pair of proof masses is affixed at a distal end of the layered pyroelectric capacitor to face the first surface and the second surface, wherein the proof masses oscillate between the first surface and the second surface such that a pyroelectric current is generated in the pyroelectric capacitor due to temperature cycling when the proof masses alternately contact the first surface and the second surface.
Multi-layer assemblies with predetermined stress profile and method for producing same
NASA Technical Reports Server (NTRS)
Heuer, Arthur H. (Inventor); Kahn, Harold (Inventor); Yang, Jie (Inventor); Phillips, Stephen M. (Inventor)
2003-01-01
Multi-layer assemblies of polysilicon thin films having predetermined stress characteristics and techniques for forming such assemblies are disclosed. In particular, a multi-layer assembly of polysilicon thin films may be produced that has a stress level of zero, or substantially so. The multi-layer assemblies comprise at least one constituent thin film having a tensile stress and at least one constituent thin film having a compressive stress. The thin films forming the multi-layer assemblies may be disposed immediately adjacent to one another without the use of intermediate layers between the thin films. Multi-layer assemblies exhibiting selectively determinable overall bending moments are also disclosed. Selective production of overall bending moments in microstructures enables manufacture of such structures with a wide array of geometrical configurations.
NASA Astrophysics Data System (ADS)
Usov, I. O.; Arendt, P. N.; Foltyn, S. R.; Stan, L.; DePaula, R. F.; Holesinger, T. G.
2010-06-01
One of the crucial steps in the second generation high temperature superconducting wire program was development of the buffer-layer architecture. The architecture designed at the Superconductivity Technology Center at Los Alamos National Laboratory consists of several oxide layers wherein each layer plays a specific role, namely: nucleation layer, diffusion barrier, biaxially textured template, and intermediate layer providing a suitable lattice match to the superconducting Y 1Ba 2Cu 3O 7 (YBCO) compound. This report demonstrates how a wide range of ion beam analysis techniques (SIMS, RBS, channeling, PIXE, PIGE, NRA and ERD) was employed for analysis of each buffer layer and the YBCO film. These results assisted in understanding of a variety of physical processes occurring during the buffer layer fabrication and helped to optimize the buffer-layer architecture as a whole.
Sayell, E.H.
1973-10-23
A radioisotopic heat source is described which includes a core of heat productive, radioisotopic material, an impact resistant layer of graphite surrounding said core, and a shell of iridium metal intermediate the core and the impact layer. The source may also include a compliant mat of iridium between the core and the iridium shell, as well as an outer covering of iridium metal about the entire heat source. (Official Gazette)
Castañeda-Espinosa, Juan Carlos; Pereira, Rosana Aparecida; Cavalcanti, Ana Paula; Mondelli, Rafael Francisco Lia
2007-01-01
The purpose of this study was to evaluate the individual contraction force during polymerization of a composite resin (Z-250), a flowable composite (Filtek Flow, FF) and a resin-modified glass ionomer cement (Vitrebond, VB), and the transmission of Z-250 composite resin polymerization contraction force through different thicknesses of FF and VB. The experiment setup consisted of two identical parallel steel plates connected to a universal testing machine. One was fixed to a transversal base and the other to the equipment's cross head. The evaluated materials were inserted into a 1-mm space between the steel plates or between the inferior steel plate and a previously polymerized layer of an intermediate material (either FF or VB) adhered to the upper steel plate. The composite resin was light-cured with a halogen lamp with light intensity of 500 mW/cm2 for 60 s. A force/time graph was obtained for each sample for up to 120 s. Seven groups of 10 specimens each were evaluated: G1: Z-250; G2: FF; G3: VB; G4: Z-250 through a 0.5-mm layer of FF; G5: Z-250 through a 1-mm layer of FF; G6: Z-250 through a 0.5-mm of VB; G7: Z-250 through a 1-mm layer of VB. They were averaged and compared using one-way ANOVA and Tukey test at a = 0.05. The obtained contraction forces were: G1: 6.3N ± 0.2N; G2: 9.8 ± 0.2N; G3: 1.8 ± 0.2N; G4: 6.8N ± 0.2N; G5: 6.9N ± 0.3N; G6: 4.0N ± 0.4N and G7: 2.8N ± 0.4N. The use of VB as an intermediate layer promoted a significant decrease in polymerization contraction force values of the restorative system, regardless of material thickness. The use of FF as an intermediate layer promoted an increase in polymerization contraction force values with both material thicknesses. PMID:19089187
Rolls, Edmund T; Mills, W Patrick C
2018-05-01
When objects transform into different views, some properties are maintained, such as whether the edges are convex or concave, and these non-accidental properties are likely to be important in view-invariant object recognition. The metric properties, such as the degree of curvature, may change with different views, and are less likely to be useful in object recognition. It is shown that in a model of invariant visual object recognition in the ventral visual stream, VisNet, non-accidental properties are encoded much more than metric properties by neurons. Moreover, it is shown how with the temporal trace rule training in VisNet, non-accidental properties of objects become encoded by neurons, and how metric properties are treated invariantly. We also show how VisNet can generalize between different objects if they have the same non-accidental property, because the metric properties are likely to overlap. VisNet is a 4-layer unsupervised model of visual object recognition trained by competitive learning that utilizes a temporal trace learning rule to implement the learning of invariance using views that occur close together in time. A second crucial property of this model of object recognition is, when neurons in the level corresponding to the inferior temporal visual cortex respond selectively to objects, whether neurons in the intermediate layers can respond to combinations of features that may be parts of two or more objects. In an investigation using the four sides of a square presented in every possible combination, it was shown that even though different layer 4 neurons are tuned to encode each feature or feature combination orthogonally, neurons in the intermediate layers can respond to features or feature combinations present is several objects. This property is an important part of the way in which high capacity can be achieved in the four-layer ventral visual cortical pathway. These findings concerning non-accidental properties and the use of neurons in intermediate layers of the hierarchy help to emphasise fundamental underlying principles of the computations that may be implemented in the ventral cortical visual stream used in object recognition. Copyright © 2018 Elsevier Inc. All rights reserved.
Runtime Verification of C Programs
NASA Technical Reports Server (NTRS)
Havelund, Klaus
2008-01-01
We present in this paper a framework, RMOR, for monitoring the execution of C programs against state machines, expressed in a textual (nongraphical) format in files separate from the program. The state machine language has been inspired by a graphical state machine language RCAT recently developed at the Jet Propulsion Laboratory, as an alternative to using Linear Temporal Logic (LTL) for requirements capture. Transitions between states are labeled with abstract event names and Boolean expressions over such. The abstract events are connected to code fragments using an aspect-oriented pointcut language similar to ASPECTJ's or ASPECTC's pointcut language. The system is implemented in the C analysis and transformation package CIL, and is programmed in OCAML, the implementation language of CIL. The work is closely related to the notion of stateful aspects within aspect-oriented programming, where pointcut languages are extended with temporal assertions over the execution trace.
NASA Technical Reports Server (NTRS)
Schmeckpeper, K. R.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Electrical Power Distribution and Control (EPD and C) hardware. The EPD and C hardware performs the functions of distributing, sensing, and controlling 28 volt DC power and of inverting, distributing, sensing, and controlling 117 volt 400 Hz AC power to all Orbiter subsystems from the three fuel cells in the Electrical Power Generation (EPG) subsystem. Volume 2 continues the presentation of IOA analysis worksheets and contains the potential critical items list.
Independent Orbiter Assessment (IOA): Analysis of the life support and airlock support subsystems
NASA Technical Reports Server (NTRS)
Arbet, Jim; Duffy, R.; Barickman, K.; Saiidi, Mo J.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Life Support System (LSS) and Airlock Support System (ALSS). Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode. The LSS provides for the management of the supply water, collection of metabolic waste, management of waste water, smoke detection, and fire suppression. The ALSS provides water, oxygen, and electricity to support an extravehicular activity in the airlock.
McArthur, Polly; Burch, Lillian; Moore, Katherine; Hodges, Mary Sue
2016-07-01
This article describes interactive learning about independent living for people with disabilities and features the partnership of the College of Nursing and a Center for Independent Living (CIL). Using qualitative descriptive approach, students' written reflections were analyzed. Through "Xtreme Challenge," 82 undergraduate nursing students participated in aspects of independent living as well as identifying barriers. Students were engaged and learned to consider the person before the disability. Moreover, students valued the activity leaders' openness, which facilitated understanding the point of view of a person with disability. The value of partnership was evident as it allowed students to participate in active learning, which led to growth in the affective domain. Students became aware of potential education resources through the CIL. This article will guide educators in designing experiences that teach nursing care at the individual, family, and community level for people living with disabilities. © 2015 Association of Rehabilitation Nurses.
Improved photovoltaic properties of ZnTeO-based intermediate band solar cells
NASA Astrophysics Data System (ADS)
Tanaka, Tooru; Saito, Katsuhiko; Guo, Qixin; Yu, Kin Man; Walukiewicz, Wladek
2018-02-01
Highly mismatched ZnTe1-xOx (ZnTeO) alloy is one of the potential candidates for an absorber material in a bulk intermediate band solar cell (IBSC) because a narrow, O-derived intermediate band IB (E-) is formed well below the conduction band CB (E+) edge of the ZnTe. We have previously demonstrated the generation of photocurrent induced by two-step photon absorption (TSPA) in ZnTeO IBSCs using n-ZnO window layer. However, because of the large conduction band offset (CBO) between ZnTe and ZnO, only a small open circuit voltage (Voc) was observed in this structure. Here, we report our recent progress on the development of ZnTeO IBSCs with n-ZnS window layer. ZnS has a large direct band gap of 3.7 eV with an electron affinity of 3.9 eV that can realize a smaller CBO with ZnTe. We have grown n-type ZnS thin films on ZnTe substrates by molecular beam epitaxy (MBE), and demonstrated ZnTe solar cells and ZnTeO IBSCs using n-ZnS window layer with an improved VOC. Especially, a n-ZnS/i-ZnTe/p-ZnTe solar cell showed an improved Voc of 0.77 V, a large short-circuit current density of 6.7 mA/cm2 with a fill factor of 0.60, yielding the power conversion efficiency of 3.1 %, under 1 sun illumination.
Oriented conductive oxide electrodes on SiO2/Si and glass
Jia, Quanxi; Arendt, Paul N.
2001-01-01
A thin film structure is provided including a silicon substrate with a layer of silicon dioxide on a surface thereof, and a layer of cubic oxide material deposited upon the layer of silicon dioxide by ion-beam-assisted-deposition, said layer of cubic oxide material characterized as biaxially oriented. Preferably, the cubic oxide material is yttria-stabilized zirconia. Additional thin layers of biaxially oriented ruthenium oxide or lanthanum strontium cobalt oxide are deposited upon the layer of yttria-stabilized zirconia. An intermediate layer of cerium oxide is employed between the yttria-stabilized zirconia layer and the lanthanum strontium cobalt oxide layer. Also, a layer of barium strontium titanium oxide can be upon the layer of biaxially oriented ruthenium oxide or lanthanum strontium cobalt oxide. Also, a method of forming such thin film structures, including a low temperature deposition of a layer of a biaxially oriented cubic oxide material upon the silicon dioxide surface of a silicon dioxide/silicon substrate is provided.
Two-axis magnetic field sensor
NASA Technical Reports Server (NTRS)
Smith, Carl H. (Inventor); Nordman, Catherine A. (Inventor); Jander, Albrecht (Inventor); Qian, Zhenghong (Inventor)
2006-01-01
A ferromagnetic thin-film based magnetic field sensor with first and second sensitive direction sensing structures each having a nonmagnetic intermediate layer with two major surfaces on opposite sides thereof having a magnetization reference layer on one and an anisotropic ferromagnetic material sensing layer on the other having a length in a selected length direction and a smaller width perpendicular thereto and parallel to the relatively fixed magnetization direction. The relatively fixed magnetization direction of said magnetization reference layer in each is oriented in substantially parallel to the substrate but substantially perpendicular to that of the other. An annealing process is used to form the desired magnetization directions.
Composite armor, armor system and vehicle including armor system
Chu, Henry S.; Jones, Warren F.; Lacy, Jeffrey M.; Thinnes, Gary L.
2013-01-01
Composite armor panels are disclosed. Each panel comprises a plurality of functional layers comprising at least an outermost layer, an intermediate layer and a base layer. An armor system incorporating armor panels is also disclosed. Armor panels are mounted on carriages movably secured to adjacent rails of a rail system. Each panel may be moved on its associated rail and into partially overlapping relationship with another panel on an adjacent rail for protection against incoming ordnance from various directions. The rail system may be configured as at least a part of a ring, and be disposed about a hatch on a vehicle. Vehicles including an armor system are also disclosed.
Nonlinear instability and convection in a vertically vibrated granular bed
NASA Astrophysics Data System (ADS)
Shukla, Priyanka; Ansari, I. H.; van der Meer, D.; Lohse, Detlef; Alam, Meheboob
2015-11-01
The nonlinear instability of the density-inverted granular Leidenfrost state and the resulting convective motion in strongly shaken granular matter are analysed via a weakly nonlinear analysis. Under a quasi-steady ansatz, the base state temperature decreases with increasing height away from from the vibrating plate, but the density profile consists of three distinct regions: (i) a collisional dilute layer at the bottom, (ii) a levitated dense layer at some intermediate height and (iii) a ballistic dilute layer at the top of the granular bed. For the nonlinear stability analysis, the nonlinearities up-to cubic order in perturbation amplitude are retained, leading to the Landau equation. The genesis of granular convection is shown to be tied to a supercritical pitchfork bifurcation from the Leidenfrost state. Near the bifurcation point the equilibrium amplitude is found to follow a square-root scaling law, Ae √{ ▵} , with the distance ▵ from bifurcation point. The strength of convection is maximal at some intermediate value of the shaking strength, with weaker convection both at weaker and stronger shaking. Our theory predicts a novel floating-convection state at very strong shaking.
NASA Astrophysics Data System (ADS)
Ke, Shaoying; Lin, Shaoming; Ye, Yujie; Mao, Danfeng; Huang, Wei; Xu, Jianfang; Li, Cheng; Chen, Songyan
2018-03-01
We report a near-bubble-free low-temperature silicon (Si) wafer bonding with a thin amorphous Ge (a-Ge) intermediate layer. The DC-magnetron-sputtered a-Ge film on Si is demonstrated to be extremely flat (RMS = 0.28 nm) and hydrophilic (contact angle = 3°). The effect of the post-annealing temperature on the surface morphology and crystallinity of a-Ge film at the bonded interface is systematically identified. The relationship among the bubble density, annealing temperature, and crystallinity of a-Ge film is also clearly clarified. The crystallization of a-Ge film firstly appears at the bubble region. More interesting feature is that the crystallization starts from the center of the bubbles and sprawls to the bubble edge gradually. The H2 by-product is finally absorbed by intermediate Ge layer with crystalline phase after post annealing. Moreover, the whole a-Ge film out of the bubble totally crystallizes when the annealing time increases. This Ge integration at the bubble region leads to the decrease of the bubble density, which in turn increases the bonding strength.
NASA Astrophysics Data System (ADS)
El-Kosasy, A. M.; Abdel-Aziz, Omar; Magdy, N.; El Zahar, N. M.
2016-03-01
New accurate, sensitive and selective spectrophotometric and chemometric methods were developed and subsequently validated for determination of Imipenem (IMP), ciprofloxacin hydrochloride (CIPRO), dexamethasone sodium phosphate (DEX), paracetamol (PAR) and cilastatin sodium (CIL) in human urine. These methods include a new derivative ratio method, namely extended derivative ratio (EDR), principal component regression (PCR) and partial least-squares (PLS) methods. A novel EDR method was developed for the determination of these drugs, where each component in the mixture was determined by using a mixture of the other four components as divisor. Peak amplitudes were recorded at 293.0 nm, 284.0 nm, 276.0 nm, 257.0 nm and 221.0 nm within linear concentration ranges 3.00-45.00, 1.00-15.00, 4.00-40.00, 1.50-25.00 and 4.00-50.00 μg mL- 1 for IMP, CIPRO, DEX, PAR and CIL, respectively. PCR and PLS-2 models were established for simultaneous determination of the studied drugs in the range of 3.00-15.00, 1.00-13.00, 4.00-12.00, 1.50-9.50, and 4.00-12.00 μg mL- 1 for IMP, CIPRO, DEX, PAR and CIL, respectively, by using eighteen mixtures as calibration set and seven mixtures as validation set. The suggested methods were validated according to the International Conference of Harmonization (ICH) guidelines and the results revealed that they were accurate, precise and reproducible. The obtained results were statistically compared with those of the published methods and there was no significant difference.
Molecular and Dusty Layers of Asymptotic Giant Branch Stars Studied with the VLT Interferometer
2011-09-01
the evolution of low to intermediate mass stars towards planetary nebulae . It is also one of the most important sources of chemical enrichment of...planetary nebula (PN) phases, and is thus the most important driver for the further stellar evolution (e.g., Habing & Olofsson, 2003). Mass loss from AGB...branch (AGB) stars is the most important driver for the evolution of low to intermediate mass stars towards planetary nebulae . It is also one of the
Large area polysilicon films with predetermined stress characteristics and method for producing same
NASA Technical Reports Server (NTRS)
Heuer, Arthur H. (Inventor); Kahn, Harold (Inventor); Yang, Jie (Inventor); Phillips, Stephen M. (Inventor)
2002-01-01
Multi-layer assemblies of polysilicon thin films having predetermined stress characteristics and techniques for forming such assemblies are disclosed. In particular, a multi-layer assembly of polysilicon thin films may be produced that has a stress level of zero, or substantially so. The multi-layer assemblies comprise at least one constituent thin film having a tensile stress and at least one constituent thin film having a compressive stress. The thin films forming the multi-layer assemblies may be disposed immediately adjacent to one another without the use of intermediate layers between the thin films. Multi-layer assemblies exhibiting selectively determinable overall bending moments are also disclosed. Selective production of overall bending moments in microstructures enables manufacture of such structures with a wide array of geometrical configurations.
Mitigation of substrate defects in reticles using multilayer buffer layers
Mirkarimi, Paul B.; Bajt, Sasa; Stearns, Daniel G.
2001-01-01
A multilayer film is used as a buffer layer to minimize the size of defects on a reticle substrate prior to deposition of a reflective coating on the substrate. The multilayer buffer layer deposited intermediate the reticle substrate and the reflective coating produces a smoothing of small particles and other defects on the reticle substrate. The reduction in defect size is controlled by surface relaxation during the buffer layer growth process and by the degree of intermixing and volume contraction of the materials at the multilayer interfaces. The buffer layers are deposited at near-normal incidence via a low particulate ion beam sputtering process. The growth surface of the buffer layer may also be heated by a secondary ion source to increase the degree of intermixing and improve the mitigation of defects.
Optical Clock Distribution to VLSI Chips
1989-07-01
depletion layer edge represents a lower concentration of minority carriers, minority carriers generated outside the depletion layer statistically tend to...completed and the output voltage levels for the next state to be transfered to the intermediate buffer by means of the second pass transitor . Since 41...a sample size too small to have statistical significance, the results give an indication of the typical operating frequency that is possible with a
Corrosion resistant PEM fuel cell
Li, Yang; Meng, Wen-Jin; Swathirajan, Swathy; Harris, Stephen Joel; Doll, Gary Lynn
2001-07-17
The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell's operating environment. Stainless steels rich in CR, Ni, and Mo are particularly effective protective interlayers.
Metallization pattern on solid electrolyte or porous support of sodium battery process
Kim, Jin Yong; Li, Guosheng; Lu, Xiaochuan; Sprenkle, Vincent L.; Lemmon, John P.
2016-05-31
A new battery configuration and process are detailed. The battery cell includes a solid electrolyte configured with an engineered metallization layer that distributes sodium across the surface of the electrolyte extending the active area of the cathode in contact with the anode during operation. The metallization layer enhances performance, efficiency, and capacity of sodium batteries at intermediate temperatures at or below about 200.degree. C.
Corrosion resistant PEM fuel cell
Li, Yang; Meng, Wen-Jin; Swathirajan, Swathy; Harris, Stephen Joel; Doll, Gary Lynn
2002-01-01
The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell's operating environment. Stainless steels rich in CR, Ni, and Mo are particularly effective protective interlayers.
Corrosion resistant PEM fuel cell
Li, Yang; Meng, Wen-Jin; Swathirajan, Swathy; Harris, Stephen J.; Doll, Gary L.
1997-01-01
The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell's operating environment. Stainless steels rich in CR, Ni, and Mo are particularly effective protective interlayers.
NASA Astrophysics Data System (ADS)
Voitsekhovskii, Alexander V.; Nesmelov, Sergey N.; Dzyadukh, Stanislav M.; Varavin, Vasily S.; Dvoretsky, Sergey A.; Mikhailov, Nikolay N.; Yakushev, Maksim V.; Sidorov, Georgy Yu.
2017-11-01
Heterostructures based on n-Hg1-xCdxTe (x = 0.23-0.40) with near-surface graded-gap layers were grown by molecular beam epitaxy on Si (013) substrates. At 77 K, the admittance of the In/Al2O3/Hg1-xCdxTe metal-insulator-semiconductor (MIS) structures with grown in situ CdTe intermediate layer and without such a layer was investigated. It has been established that MIS structures of In/Al2O3/Hg1-xCdxTe with an interlayer of in situ grown CdTe are characterized by the electrical strength of the dielectric and the qualitative interface. The hysteresis of the capacitive characteristics is practically absent within a small range of variation in the bias voltage. The density of fast surface states at the minimum does not exceed 2.2 × 1010 eV-1 cm-2. MIS structures of In/Al2O3/Hg1-xCdxTe without an intermediate layer of CdTe have significantly higher densities of fast and slow surface states, as well as lower values of the differential resistance of the space-charge region in the regime of strong inversion.
Diffusion of drag-reducing polymer solutions within a rough-walled turbulent boundary layer
NASA Astrophysics Data System (ADS)
Elbing, Brian R.; Dowling, David R.; Perlin, Marc; Ceccio, Steven L.
2010-04-01
The influence of surface roughness on diffusion of wall-injected, drag-reducing polymer solutions within a turbulent boundary layer was studied with a 0.94 m long flat-plate test model at speeds of up to 10.6 m s-1 and Reynolds numbers of up to 9×106. The surface was hydraulically smooth, transitionally rough, or fully rough. Mean concentration profiles were acquired with planar laser induced fluorescence, which was the primary flow diagnostic. Polymer concentration profiles with high injection concentrations (≥1000 wppm) had the peak concentration shifted away from the wall, which was partially attributed to a lifting phenomenon. The diffusion process was divided into three zones—initial, intermediate, and final. Studies of polymer injection into a polymer ocean at concentrations sufficient for maximum drag reduction indicated that the maximum initial zone length is of the order of 100 boundary layer thicknesses. The intermediate zone results indicate that friction velocity and roughness height are important scaling parameters in addition to flow and injection conditions. Lastly, the current results were combined with those in Petrie et al. ["Polymer drag reduction with surface roughness in flat-plate turbulent boundary layer flow," Exp. Fluids 35, 8 (2003)] to demonstrate that the influence of polymer degradation increases with increased surface roughness.
Decoding the cortical transformations for visually guided reaching in 3D space.
Blohm, Gunnar; Keith, Gerald P; Crawford, J Douglas
2009-06-01
To explore the possible cortical mechanisms underlying the 3-dimensional (3D) visuomotor transformation for reaching, we trained a 4-layer feed-forward artificial neural network to compute a reach vector (output) from the visual positions of both the hand and target viewed from different eye and head orientations (inputs). The emergent properties of the intermediate layers reflected several known neurophysiological findings, for example, gain field-like modulations and position-dependent shifting of receptive fields (RFs). We performed a reference frame analysis for each individual network unit, simulating standard electrophysiological experiments, that is, RF mapping (unit input), motor field mapping, and microstimulation effects (unit outputs). At the level of individual units (in both intermediate layers), the 3 different electrophysiological approaches identified different reference frames, demonstrating that these techniques reveal different neuronal properties and suggesting that a comparison across these techniques is required to understand the neural code of physiological networks. This analysis showed fixed input-output relationships within each layer and, more importantly, within each unit. These local reference frame transformation modules provide the basic elements for the global transformation; their parallel contributions are combined in a gain field-like fashion at the population level to implement both the linear and nonlinear elements of the 3D visuomotor transformation.
ERIC Educational Resources Information Center
Elsweiler, John A., Jr.; And Others
1990-01-01
Presents summaries of 12 papers presented at the 1990 Computers in Libraries Conference. Topics discussed include online searching; microcomputer-based serials management; microcomputer-based workstations; online public access catalogs (OPACs); multitype library networking; CD-ROM searches; locally mounted online databases; collection evaluation;…
... Health Information Spanish Language Health Information Related Information La historia de Ana: Cómo ella y su familia aprendieron sobre las lesiones depor… Ana's Story Lesiones deportivas: Esenciales: hojas informativas de fácil lectura View/Download/Order Publications Sports Injuries, Easy-to- ...
Layered composites made from bimetallic strips produced by plasma spraying of TiAl on niobium
NASA Astrophysics Data System (ADS)
Burmistrov, V. I.; Antonova, A. V.; Povarova, K. B.; Bannykh, I. O.
2007-12-01
The production and structure of a multilayer TiAl/Nb composite material made from bimetallic TiAl/Nb strips fabricated by plasma spraying of TiAl granules onto niobium plates are studied. Here, 3-mm-and 2-mm-thick plates of a layered composite material (LCM) are produced by hot isostatic pressing of a stack of 35 bimetallic plates followed by hot rolling (the total degree of reduction is 78.6 and 85.7%, respectively). The LCM consists of discontinuous TiAl layers separated by niobium layers, and the adhesion between the layers is good. Diffusional intermediate layers form at the TiAl/Nb interfaces in the 3-mm-thick LCM and consist of the following two solid solutions: an α2-Ti3Al-based solid solution contains up to 28 at % Nb, and a niobiumbased solid solution contains up to 27 at % Ti and 32 at % Al. The diffusional intermediate layers in the 2-mmthick LCM plates consist of an α2-Ti3Al-based solid solution with up to 16.0 at % Nb; a τ-Ti3Al2Nb-or Ti4Al3Nb-based solid solution with 51.5 at % Ti, 32 at % Al, and 16.5 at % Nb; and a niobium-based solid solution with up to 22 at % Ti and 30.5 at % Al. When a bimetallic TiAl/Nb strip is fabricated by plasma spraying of granules of the Ti-48 at % Al alloy, this alloy is depleted of aluminum to 42 45 at %, and the fraction of the α2-Ti3Al phase in the sprayed layer increases. When the LCM is produced by hot isostatic pressing followed by hot rolling, the layer of plain niobium (Nb1) dissolves up to 5 at % Ti and 7 at % Al.
Yoon, Hyung-In; Yeo, In-Sung; Yi, Yang-Jin; Kim, Sung-Hun; Lee, Jai-Bong; Han, Jung-Suk
2015-01-01
The purposes of this study were to evaluate the effects of intermediate ceramics on the adhesion between the zirconia core and veneer ceramics. The polished surfaces of fully sintered Y-TZP blocks received three different treatments: (1) connector (C), (2) liner (L) or (3) wash layer (W). All the treated zirconia blocks were veneered with either (a) fluorapatite glass-ceramic (E) or (b) feldspathic porcelain (V) and divided into four groups (CE, CV, LE and WV). For the control group, the testing surfaces of metal blocks were veneered with feldspathic porcelain (VM). A half of the samples in each group (n = 21) were exposed to thermocycling, while the other half of the specimens were stored at room temperature under dry conditions. All specimens were subjected to the shear test and the failed surfaces were microscopically examined. The elemental distribution at the zirconia core/veneer interface was analyzed. The specimens in Groups CE and CV exhibited significantly greater mean bond strength values than those in Groups LE and WV, respectively (p < 0.05). However, the mean bond strengths significantly decreased in the connector groups (CE and CV) after thermal cycling (p < 0.05). The elemental analysis suggested diffusion of ceramic substances into the zirconia surface. A glass-ceramic based connector is significantly more favorable to core/veneer adhesion than the other intermediate ceramics evaluated in the study. However, thermal cycling affected the bond strength at the core/veneer interface differently according to the intermediate ceramics.
Mesquita-Guimarães, Késsia Suênia Fidelis de; Sabbatini, Iliana Ferraz; Almeida, Cintia Guimarães de; Galo, Rodrigo; Nelson-Filho, Paulo; Borsatto, Maria Cristina
2016-01-01
Dental sealants are important for prevention of carious lesions, if they have good shear strength. The aim of this study was to evaluate the shear bond strength (SBS) of two sealants to saliva-contaminated and non-contaminated enamel with and without an intermediate adhesive layer underneath the sealant. Ninety flat enamel surfaces from human third molars were randomly assigned to 6 groups (n=15): F (control): Fluroshield(tm) sealant; EWB (control): Embrace(tm) WetBond(tm); SB/F: Single Bond adhesive system + F; SB/EWB, s-SB/F and s-SB/EWB. In the s-SB/F and s-SB/EWB groups, the acid-etched enamel was contaminated with 0.01 mL of fresh human saliva for 20 s. Sealant cylinders were bonded to enamel surface with and without an intermediate adhesive system layer. The shear tests were performed using a universal testing machine (0.5 mm/min). Data were analyzed statistically by Kruskal-Wallis and Mann-Whitney tests (α=0.05). F presented higher mean SBS than EWB in all experimental conditions. The lowest SBS mean was obtained for EWB on contaminated enamel (p<0.05). In conclusion, an adhesive system layer should be used prior to sealant placement, in both dry and saliva-contaminated enamel. F had the best performance in all experimental conditions. EWB sealant showed very low results, but an adhesive layer underneath the sealant increased its SBS even after salivary contamination.
Solid-state Bonding of Superplastic Aluminum Alloy 7475 Sheet
NASA Technical Reports Server (NTRS)
Byun, T. D. S.; Vastava, R. B.
1985-01-01
Experimental works were carried out to study the feasibility of solid state bonding of superplastic aluminum 7475 sheet. Amount of deformation, bonding time, surface cleaning method and intermediate layer were the process parameters investigated. Other parameters, held constant by the superplastic forming condition which is required to obtain a concurrent solid state bonding, are bonding temperature, bonding pressure and atmosphere. Bond integrity was evaluated through metallographic examination, X-ray line scan analysis, SEM fractographic analysis and lap shear tests. The early results of the development program indicated that sound solid state bonding was accomplished for this high strength 7475 alloy with significant amounts of deformation. A thin intermediate layer of the soft 5052 aluminum alloy aided in achieving a solid state bonding by reducing the required amount of plastic deformation at the interface. Bond strength was substantially increased by a post bond heat treatment.
Theoretical Insights to Bulk Activity Towards Oxygen Evolution in Oxyhydroxides
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doyle, Andrew D.; Bajdich, Michal; Vojvodic, Aleksandra
The nature of the electrochemical water splitting activity of layered pure and Fe-doped NiOOH is investigated using density functional theory calculations. We find similar thermodynamics for the oxygen evolution reaction (OER) intermediates between the layers of oxyhydroxides, that is, in the bulk of the materials as on the (001) surface. The effect of interlayer spacing on adsorption energy is affected by both the crystal structure and the level of hydrogenation of the active sites. For the Fe-doped NiOOH, we observe general weakening of binding between the different OER intermediates and the catalyst material. The calculated OER activity depends both onmore » doping and interlayer spacing, and our results are generally congruent with available experimental data. In conclusion, these results suggest that such interlayer “bulk” sites may contribute to measured OER activity for both the pure and Fe-doped NiOOH catalysts.« less
Interfacial Metal-Oxide Interactions in Resistive Switching Memories.
Cho, Deok-Yong; Luebben, Michael; Wiefels, Stefan; Lee, Kug-Seung; Valov, Ilia
2017-06-07
Metal oxides are commonly used as electrolytes for redox-based resistive switching memories. In most cases, non-noble metals are directly deposited as ohmic electrodes. We demonstrate that irrespective of bulk thermodynamics predictions an intermediate oxide film a few nanometers in thickness is always formed at the metal/insulator interface, and this layer significantly contributes to the development of reliable switching characteristics. We have tested metal electrodes and metal oxides mostly used for memristive devices, that is, Ta, Hf, and Ti and Ta 2 O 5 , HfO 2 , and SiO 2 . Intermediate oxide layers are always formed at the interfaces, whereas only the rate of the electrode oxidation depends on the oxygen affinity of the metal and the chemical stability of the oxide matrix. Device failure is associated with complete transition of short-range order to a more disordered main matrix structure.
Superconducting composite with multilayer patterns and multiple buffer layers
Wu, X.D.; Muenchausen, R.E.
1993-10-12
An article of manufacture is described including a substrate, a patterned interlayer of a material selected from the group consisting of magnesium oxide, barium-titanium oxide or barium-zirconium oxide, the patterned interlayer material overcoated with a secondary interlayer material of yttria-stabilized zirconia or magnesium-aluminum oxide, upon the surface of the substrate whereby an intermediate article with an exposed surface of both the overcoated patterned interlayer and the substrate is formed, a coating of a buffer layer selected from the group consisting of cerium oxide, yttrium oxide, curium oxide, dysprosium oxide, erbium oxide, europium oxide, iron oxide, gadolinium oxide, holmium oxide, indium oxide, lanthanum oxide, manganese oxide, lutetium oxide, neodymium oxide, praseodymium oxide, plutonium oxide, samarium oxide, terbium oxide, thallium oxide, thulium oxide, yttrium oxide and ytterbium oxide over the entire exposed surface of the intermediate article, and, a ceramic superconductor. 5 figures.
Theoretical Insights to Bulk Activity Towards Oxygen Evolution in Oxyhydroxides
Doyle, Andrew D.; Bajdich, Michal; Vojvodic, Aleksandra
2017-04-07
The nature of the electrochemical water splitting activity of layered pure and Fe-doped NiOOH is investigated using density functional theory calculations. We find similar thermodynamics for the oxygen evolution reaction (OER) intermediates between the layers of oxyhydroxides, that is, in the bulk of the materials as on the (001) surface. The effect of interlayer spacing on adsorption energy is affected by both the crystal structure and the level of hydrogenation of the active sites. For the Fe-doped NiOOH, we observe general weakening of binding between the different OER intermediates and the catalyst material. The calculated OER activity depends both onmore » doping and interlayer spacing, and our results are generally congruent with available experimental data. In conclusion, these results suggest that such interlayer “bulk” sites may contribute to measured OER activity for both the pure and Fe-doped NiOOH catalysts.« less
Corrosion resistant PEM fuel cell
Li, Y.; Meng, W.J.; Swathirajan, S.; Harris, S.J.; Doll, G.L.
1997-04-29
The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell`s operating environment. Stainless steels rich in Cr, Ni, and Mo are particularly effective protective interlayers. 6 figs.
NASA Technical Reports Server (NTRS)
Gasso, Santiago; O'Neill, Norm
2006-01-01
We present sunphotometer-retrieved and in situ fine mode fractions (FMF) measured onboard the same aircraft during the ACE-Asia experiment. Comparisons indicate that the latter can be used to identify whether the aerosol under observation is dominated by a mixture of modes or a single mode. Differences between retrieved and in situ FMF range from 5-20%. When profiles contained multiple layers of aerosols, the retrieved and measured FMF were segregated by layers. The comparison of layered and total FMF from the same profile indicates that columnar values are intermediate to those derived from layers. As a result, a remotely sensed FMF cannot be used to distinguish whether the aerosol under observation is composed of layers each with distinctive modal features or all layers with the same modal features. Thus, the use of FMF in multiple layer environments does not provide unique information on the aerosol under observation.
Sarin, V.K.
1990-08-21
An oxidation resistant, high temperature thermal cycling resistant coated ceramic article for ceramic heat engine applications is disclosed. The substrate is a silicon-based material, i.e. a silicon nitride- or silicon carbide-based monolithic or composite material. The coating is a graded coating of at least two layers: an intermediate AlN or Al[sub x]N[sub y]O[sub z] layer and an aluminum oxide or zirconium oxide outer layer. The composition of the coating changes gradually from that of the substrate to that of the AlN or Al[sub x]N[sub y]O[sub z] layer and further to the composition of the aluminum oxide or zirconium oxide outer layer. Other layers may be deposited over the aluminum oxide layer. A CVD process for depositing the graded coating on the substrate is also disclosed.
Sarin, Vinod K.
1990-01-01
An oxidation resistant, high temperature thermal cycling resistant coated ceramic article for ceramic heat engine applications. The substrate is a silicon-based material, i.e. a silicon nitride- or silicon carbide-based monolithic or composite material. The coating is a graded coating of at least two layers: an intermediate AlN or Al.sub.x N.sub.y O.sub.z layer and an aluminum oxide or zirconium oxide outer layer. The composition of the coating changes gradually from that of the substrate to that of the AlN or Al.sub.x N.sub.y O.sub.z layer and further to the composition of the aluminum oxide or zirconium oxide outer layer. Other layers may be deposited over the aluminum oxide layer. A CVD process for depositing the graded coating on the substrate is also disclosed.
Lessing, Paul A [Idaho Falls, ID
2008-07-22
An electrochemically active hydrogen diffusion barrier which comprises an anode layer, a cathode layer, and an intermediate electrolyte layer, which is conductive to protons and substantially impermeable to hydrogen. A catalytic metal present in or adjacent to the anode layer catalyzes an electrochemical reaction that converts any hydrogen that diffuses through the electrolyte layer to protons and electrons. The protons and electrons are transported to the cathode layer and reacted to form hydrogen. The hydrogen diffusion barrier is applied to a polymeric substrate used in a storage tank to store hydrogen under high pressure. A storage tank equipped with the electrochemically active hydrogen diffusion barrier, a method of fabricating the storage tank, and a method of preventing hydrogen from diffusing out of a storage tank are also disclosed.
Lessing, Paul A.
2004-09-07
An electrochemically active hydrogen diffusion barrier which comprises an anode layer, a cathode layer, and an intermediate electrolyte layer, which is conductive to protons and substantially impermeable to hydrogen. A catalytic metal present in or adjacent to the anode layer catalyzes an electrochemical reaction that converts any hydrogen that diffuses through the electrolyte layer to protons and electrons. The protons and electrons are transported to the cathode layer and reacted to form hydrogen. The hydrogen diffusion barrier is applied to a polymeric substrate used in a storage tank to store hydrogen under high pressure. A storage tank equipped with the electrochemically active hydrogen diffusion barrier, a method of fabricating the storage tank, and a method of preventing hydrogen from diffusing out of a storage tank are also disclosed.
Interrogating the superconductor Ca- 10(Pt 4As 8)(Fe 2-xPt xAs 2) 5 Layer-by-layer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Jisun; Zhu, Yimei; Nam, Hyoungdo
2016-10-14
Ever since the discovery of high-Tc superconductivity in layered cuprates, the roles that individual layers play have been debated, due to difficulty in layer-by-layer characterization. While there is similar challenge in many Fe-based layered superconductors, the newly-discovered Ca 10(Pt 4As 8)(Fe 2As 2) 5 provides opportunities to explore superconductivity layer by layer, because it contains both superconducting building blocks (Fe 2As 2 layers) and intermediate Pt 4As 8 layers. Cleaving a single crystal under ultra-high vacuum results in multiple terminations: an ordered Pt 4As 8 layer, two reconstructed Ca layers on the top of a Pt 4As 8 layer, andmore » disordered Ca layer on the top of Fe 2As 2 layer. The electronic properties of individual layers are studied using scanning tunneling microscopy/spectroscopy (STM/S), which reveals different spectra for each surface. Remarkably superconducting coherence peaks are seen only on the ordered Ca/Pt 4As 8 layer. Our results indicate that an ordered structure with proper charge balance is required in order to preserve superconductivity.« less
Interrogating the superconductor Ca10(Pt4As8)(Fe2-xPtxAs2)5 Layer-by-layer.
Kim, Jisun; Nam, Hyoungdo; Li, Guorong; Karki, A B; Wang, Zhen; Zhu, Yimei; Shih, Chih-Kang; Zhang, Jiandi; Jin, Rongying; Plummer, E W
2016-10-14
Ever since the discovery of high-T c superconductivity in layered cuprates, the roles that individual layers play have been debated, due to difficulty in layer-by-layer characterization. While there is similar challenge in many Fe-based layered superconductors, the newly-discovered Ca 10 (Pt 4 As 8 )(Fe 2 As 2 ) 5 provides opportunities to explore superconductivity layer by layer, because it contains both superconducting building blocks (Fe 2 As 2 layers) and intermediate Pt 4 As 8 layers. Cleaving a single crystal under ultra-high vacuum results in multiple terminations: an ordered Pt 4 As 8 layer, two reconstructed Ca layers on the top of a Pt 4 As 8 layer, and disordered Ca layer on the top of Fe 2 As 2 layer. The electronic properties of individual layers are studied using scanning tunneling microscopy/spectroscopy (STM/S), which reveals different spectra for each surface. Remarkably superconducting coherence peaks are seen only on the ordered Ca/Pt 4 As 8 layer. Our results indicate that an ordered structure with proper charge balance is required in order to preserve superconductivity.
Inertial floaters in stratified turbulence
NASA Astrophysics Data System (ADS)
Sozza, A.; De Lillo, F.; Boffetta, G.
2018-01-01
We investigate numerically the dynamics and statistics of inertial particles transported by stratified turbulence, in the case of particle density intermediate in the average density profile of the fluid. Under these conditions, particles tend to form a thin layer around the corresponding fluid isopycnal. The thickness of the resulting layer is determined by a balance between buoyancy (which attracts the particle to the isopycnal) and inertia (which prevents them from following it exactly). By means of extensive numerical simulations, we explore the parameter space of the system and we find that in a range of parameters particles form fractal clusters within the layer.
NASA Technical Reports Server (NTRS)
Cooper, K. G.
2000-01-01
Rapid prototyping (RP) is a layer-by-layer-based additive manufacturing process for constructing three-dimensional representations of a computer design from a wax, plastic, or similar material. Wire arc spray (WAS) is a metal spray forming technique, which deposits thin layers of metal onto a substrate or pattern. Marshall Space Flight Center currently has both capabilities in-house, and this project proposed merging the two processes into an innovative manufacturing technique, in which intermediate injection molding tool halves were to be fabricated with RP and WAS metal forming.
Magnetoelectric Effect in Gallium Arsenide-Nickel-Tin-Nickel Multilayer Structures
NASA Astrophysics Data System (ADS)
Filippov, D. A.; Tikhonov, A. A.; Laletin, V. M.; Firsova, T. O.; Manicheva, I. N.
2018-02-01
Experimental data have been presented for the magnetoelectric effect in nickel-tin-nickel multilayer structures grown on a GaAs substrate by cathodic electrodeposition. The method of fabricating these structures has been described, and the frequency dependence of the effect has been demonstrated. It has been shown that tin used as an intermediate layer reduces mechanical stresses due to the phase mismatch at the Ni-GaAs interface and, thus, makes it possible to grow good structures with a 70-μm-thick Ni layer. The grown structures offer good adhesion between layers and a high Q factor.
Environmental Barrier Coatings Having a YSZ Top Coat
NASA Technical Reports Server (NTRS)
Lee, Kang N.; Gray, Hugh (Technical Monitor)
2002-01-01
Environmental barrier coatings (EBCs) with a Si bond coat, a yttria-stabilized zirconia (YSZ) top coat, and various intermediate coats were investigated. EBCs were processed by atmospheric pressure plasma spraying. The EBC durability was determined by thermal cycling tests in water vapor at 1300 C and 1400 C, and in air at 1400 C and 1500 C. EBCs with a mullite (3Al2O3 (dot) 2SiO2) + BSAS (1 - xBaO (dot) xSrO (dot) Al2O3 (dot) 2SiO2) intermediate coat were more durable than EBCs with a mullite intermediate coat, while EBCs with a mullite/BSAS duplex intermediate coat resulted in inferior durability. The improvement with a mullite + BSAS intermediate coat was attributed to enhanced compliance of the intermediate coat due to the addition of a low modulus BSAS second phase. Mullite + BSAS/YSZ and BSAS/YSZ interfaces produced a low melting (less than 1400 C) reaction product, which is expected to degrade the EBC performance by increasing the thermal conductivity. EBCs with a mullite + BSAS / graded mullite + YSZ intermediate coat showed the best durability among the EBCs investigated in this study. This improvement was attributed to diffused CTE (Coefficient of Thermal Expansion) mismatch stress and improved chemical stability due to the compositionally graded mullite+YSZ layer.
NASA Astrophysics Data System (ADS)
Qiao, Yanqiang; Guo, Xiping
2010-10-01
Cr-modified silicide coatings were prepared on a Ti-Nb-Si based ultrahigh temperature alloy by Si-Cr co-deposition at 1250 °C, 1350 °C and 1400 °C for 5-20 h respectively. It was found that both coating structure and phase constituents changed significantly with increase in the co-deposition temperature and holding time. The outer layers in all coatings prepared at 1250 °C for 5-20 h consisted of (Ti,X) 5Si 3 (X represents Nb, Cr and Hf elements). (Ti,X) 5Si 4 was found as the only phase constituent in the intermediate layers in both coatings prepared at 1250 °C for 5 and 10 h, but the intermediate layers in the coatings prepared at 1250 °C for 15 and 20 h were mainly composed of (Ti,X) 5Si 3 phase that was derived from the decomposition of (Ti,X) 5Si 4 phase. In the coating prepared at 1350 °C for 5 h, single (Ti,X) 5Si 3 phase was found in its outmost layer, the same as that in the outer layers in the coatings prepared at 1250 °C; but in the coatings prepared at 1350 °C for 10-20 h, (Nb 1.95Cr 1.05)Cr 2Si 3 ternary phase was found in the outmost layers besides (Ti,X) 5Si 3 phase. In the coatings prepared at 1400 °C for 5-20 h, (Nb 1.95Cr 1.05)Cr 2Si 3 ternary phase was the single phase constituent in their outmost layers. The phase transformation (Ti,X) 5Si 4 → (Ti,X) 5Si 3 + Si occurred in the intermediate layers of the coatings prepared at 1350 and 1400 °C with prolonging co-deposition time, similar to the situation in the coatings prepared at 1250 °C for 15 and 20 h, but this transformation has been speeded up by increase in the co-deposition temperature. The transitional layers were mainly composed of (Ti,X) 5Si 3 phase in all coatings. The influence of co-deposition temperature on the diffusion ability of Cr atoms was greater than that of Si atoms in the Si-Cr co-deposition processes investigated. The growth of coatings obeyed inverse logarithmic laws at all three co-deposition temperatures. The Si-Cr co-deposition coating prepared at 1350 °C for 10 h showed a good oxidation resistance due to the formation of SiO 2 and Nb, Cr-doped TiO 2 scale after oxidation at 1250 °C for 10 h.
75 FR 76466 - Ocean Transportation Intermediary License Applicants
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-08
... FEDERAL MARITIME COMMISSION Ocean Transportation Intermediary License Applicants Notice is hereby... Transportation Intermediary (OTI) pursuant to section 19 of the Shipping Act of 1984 as amended (46 U.S.C... Office of Transportation Intermediaries, Federal Maritime Commission, Washington, DC 20573. CIL Freight...
U.S. EPA, Pesticide Product Label, INSECTICIDE CONCENTRATE, 02/11/1985
2011-04-21
... ". ... w ••• 11 dft ... ln- .... el ..... wi" .... 4 h., • .. 0 .... . cil eft ..... If I"'tet'''' ,11'1. If ••• 111."- • "I' •• Alee -.ltI"._ C.II. ",11.:1 ... 1_ ... ,tI,. ...
... visit FDA's videos for consumers on YouTube Administrando Medicina a los Niños Cuando los niños pequeños están ... ser difícil que ellos llegen a tomar su medicina. Vea este vídeo para obtener consejos de un ...
Xu, Zhijun; Yang, Xiao; Wei, Qichao; Zhao, Weilong; Cui, Beiliang; Yang, Xiaoning; Sahai, Nita
2018-06-11
Understanding the molecular mechanism of protein adsorption on solids is critical to their applications in materials synthesis and tissue engineering. Though the water phase at the surface/water interface has been recognized as three types: free water in the bulk region, intermediate water phase and surface-bound water layers adjacent to the surface, the roles of the water and surface in determining the protein adsorption are not clearly identified, particularly at the quantitative level. Herein, we provide a methodology involving the combination of microsecond strengthen sampling simulation and force integration to quantitatively characterize the water-induced contribution and the peptide-surface interactions into the adsorption free energy. Using hydroxyapatite and graphene surfaces as examples, we demonstrate how the distinct interfacial features dominate the delicate force balance between these two thermodynamics parameters, leading to surface preference/resistance to peptide adsorption. Specifically, the water layer provides sustained repelling force against peptide adsorption, as indicated by a monotonic increase in the water-induced free energy profile, whereas the contribution to the free energy from the surface effect is thermodynamically favorable, thus acting as the dominant driving force for peptide adsorptions. More importantly, the revealed adsorption mechanism is critically dictated by the distribution of water phase at the solid/water interface, which plays a crucial role in establishing the force balance between the interactions of the peptide with the water layer and the surface. For the HAP surface, the charged peptide exhibits strong binding affinity to the surface, which is ascribed to the controlling contribution of peptide-surface interaction in the intermediate water phase and the surface-bound water layers are observed as the origin of bioresistance of solid surfaces towards the adsorption of charge-neutral peptides. The preferred peptide adsorption on the graphene, however, is dominated by the surface-induced component at the water layers adjacent to the surface. Our results further elucidate that the intermediate water phase significantly shortens the effective range of the surface dispersion force to guide the diffusion of the peptide to the interface, in sharp contrast to the observation in interfacial systems involving the strong water-surface interaction.
Ba2F2Fe(1.5)Se3: An Intergrowth Compound Containing Iron Selenide Layers.
Driss, Dalel; Janod, Etienne; Corraze, Benoit; Guillot-Deudon, Catherine; Cario, Laurent
2016-03-21
The iron selenide compound Ba2F2Fe(1.5)Se3 was synthesized by a high-temperature ceramic method. The single-crystal X-ray structure determination revealed a layered-like structure built on [Ba2F2](2+) layers of the fluorite type and iron selenide layers [Fe(1.5)Se3](2-). These [Fe1.5Se3](2-) layers contain iron in two valence states, namely, Fe(II+) and Fe(III+) located in octahedral and tetrahedral sites, respectively. Magnetic measurements are consistent with a high-spin state for Fe(II+) and an intermediate-spin state for Fe(III+). Moreover, susceptibility and resistivity measurements demonstrate that Ba2F2Fe(1.5)Se3 is an antiferromagnetic insulator.
Architectures and criteria for the design of high efficiency organic photovoltaic cells
Rand, Barry; Forrest, Stephen R; Pendergrast Burk, Diane
2015-03-31
A method for fabricating an organic photovoltaic cell includes providing a first electrode; depositing a series of at least seven layers onto the first electrode, each layer consisting essentially of a different organic semiconductor material, the organic semiconductor material of at least an intermediate layer of the sequence being a photoconductive material; and depositing a second electrode onto the sequence of at least seven layers. One of the first electrode and the second electrode is an anode and the other is a cathode. The organic semiconductor materials of the series of at least seven layers are arranged to provide a sequence of decreasing lowest unoccupied molecular orbitals (LUMOs) and a sequence of decreasing highest occupied molecular orbitals (HOMOs) across the series from the anode to the cathode.
Carbonate system parameters and anthropogenic CO2 in the North Aegean Sea during October 2013
NASA Astrophysics Data System (ADS)
Krasakopoulou, E.; Souvermezoglou, E.; Giannoudi, L.; Goyet, C.
2017-10-01
Data of AT (total alkalinity) and CT (total inorganic carbon) collected during October 2013, on a N-S transect crossing the North of Lemnos basin allowed to identify the peculiarities of the CO2 system in the North Aegean Sea and estimate the anthropogenic CO2 (CANT) concentrations. Extremely high concentrations of AT and CT were recorded in the upper layer of the North Aegean reflecting the high loads of AT and CT by the brackish BSW (Black Sea Water) outflowing through the Dardanelles strait and by the rivers runoff. Both AT and CT exhibit strong negative linear correlation with salinity in the upper layer (0-20 m). Investigation of the AT-S relationship along with the salinity adjustment of AT revealed excess alkalinity throughout the water column in relation to the surface waters implying a possible occurrence of non-carbonate alkalinity inputs as well as of other processes that take place probably over the extended shelves and contribute to the alkalinity surplus. The intermediate layer occupied by the Modified Levantine Intermediate Water (MLIW) mass exhibits the lowest CT and AT concentrations, while rather elevated AT and CT concentrations characterize the North Aegean Deep Water (NAgDW) mass filling the deep layer of the North of Lemnos basin linked to previous dense water formation episodes. High anthropogenic CO2 content was detected at intermediate and deep layers of the North Aegean reflecting the effective transportation of the absorbed atmospheric CO2 from the surface to the deeper waters via the dense water formation episodes. The MLIW layer is more affected by the penetration of CANT than the NAgDW that fills the deep part of the basin. The observed variability of CANT distribution reflects the influence of the intensity of dense water formation events, of the different θ/S properties of the newly formed dense waters as well as of the diverse submarine pathways followed by the cascading dense waters. The invasion of CANT has lead to more acidic conditions and to lower saturation degree of calcium carbonate in relation to the preindustrial era. The findings of this study provide baseline information about the carbonate system properties of the North Aegean and highlight its active role in sequestering and storing anthropogenic CO2.
Effect of transmitter turn-off time on transient soundings
Fitterman, D.V.; Anderson, W.L.
1987-01-01
A general procedure for computing the effect of non-zero turn-off time on the transient electromagnetic response is presented which can be applied to forward and inverse calculation methods for any transmitter-receiver configuration. We consider in detail the case of a large transmitter loop which has a receiver coil located at the center of the loop (central induction or in-loop array). For a linear turn-off ramp of width t0, the voltage response is shown to be the voltage due to an ideal step turn-off averaged over windows of width t0. Thus the effect is similar to that obtained by using averaging windows in the receiver. In general when time zero is taken to be the end of the ramp, the apparent resistivity increases for a homogeneous half-space over a limited time range. For time zero taken to be the start of the ramp the apparent resistivity is affected in the opposite direction. The effect of the ramp increases with increasing t0 and first-layer resistivity, is largest during the intermediate stage, and decreases with increasing time. It is shown that for a ramp turn-off, there is no effect in the early and late stages. For two-layered models with a resistive first layer (??1>??2), the apparent resistivity is increased in the intermediate stage. When the first layer is more conductive than the second layer (??1?2) and the layer thickness is comparable or greater than the loop radius, similar results are obtained; however, when the layer is thin compared to the loop radius the apparent resistivity is initially decreased and then increases as time increases. Examples are presented which illustrate the strong influence of the geoelectrical section on the turn-off effect. Neglecting the turn-off ramp will affect data interpretation as shown by field examples; the influence is the greatest on near-surface layer parameters. ?? 1987.
Costacurta, L; de Carvalho, C A; König, B; Bilotta, J A
1976-01-01
An electronmicroscopical study of the enamel organ of the upper incisors germs of Wistar rats was performed to analyse the ultrastructural features of the cells of the inner epithelium, the intermediate layer and the stellate reticulum, during preimary, young, transitional and mineralized enamel phases of amelogenesis. So, it was observed that the mitochondria in the ameloblasts are ovoid before the beginning of the enamel matrix formation and in the primary and young enamel phases. However, in the transitional and mineralized phases, these organelles are long and tortuous and some are characterized by a compact structure. In the cells of intermediate layer and stellate reticulum, the mitochondria are ovoid until the beginning of the mineralized phase. At the ending of this phase, these organelles are very long and present irregular form; many of them show also a compact structure. The "zonula adhaerens" could be observed only in the ameloblasts of the primary and young enamel phase. The cytoplasm of ameloblasts, during primary and young enamel phases is characterized by an abundance of free ribosomes and a branular endoplasmic reticulum; but during transitional and mineralized enamel phases, the cytoplasm of these cells shows little granular endoplasmic reticulum and free ribosomes, but ehe agranular endoplasmic reticulum is present. The granular endoplasmic reticulum and free ribosomes are abundant in the cells of the intermediate layer and stellate reticulum at the ending of the young enamel phase, in the transitional enamel phase and in the beginning of the minieralized phase. During different phases of amelogenesis, in the three above referred layers of the enamel organ, were also studied the features of the Golgi apparatus the presence and topographic distribution of the pigment granules, as well as the lysosomes, desmosomes and the tonophibriles.
Influence of oxygen on the carbide formation on tungsten
NASA Astrophysics Data System (ADS)
Luthin, J.; Linsmeier, Ch.
2001-03-01
As a first wall material in nuclear fusion devices, tungsten will interact with carbon and oxygen from the plasma. In this study, we report on the process of thermally induced carbide formation of thin carbon films on polycrystalline tungsten and the influence of oxygen on this process. All investigations are performed using X-ray photoelectron spectroscopy (XPS). Carbon films are supplied through electron beam evaporation of graphite. The carbidization process, monitored during increased substrate temperature, can be divided into four phases. In phase I disordered carbon converts into graphite-like carbon. In phase II significant diffusion and the reaction to W 2C is observed, followed by phase III which is dominated by the presence of W 2C and the beginning reaction to WC. Finally in phase IV only WC is present, but the total carbon amount has strongly decreased. Different mechanisms of oxygen influence on the carbide formation are proposed and measurements of the reaction of carbon on tungsten with intermediate oxide layers are presented in detail. A WO 2+ x intermediate layer completely inhibits the carbide formation, while a WO 2 layer leads to WC formation at temperatures above 1270 K.
NASA Astrophysics Data System (ADS)
Carrada, M.; Haj Salem, A.; Pecassou, B.; Paillard, V.; Ben Assayag, G.
2018-03-01
2D networks of Si and Ag nanocrystals have been fabricated in the same SiO2 matrix by Ultra-Low-Energy Ion-Beam-Synthesis. Our synthesis scheme differs from a simple sequential ion implantation and its key point is the control of the matrix integrity through an appropriate intermediate thermal annealing. Si nanocrystal layer is synthesised first due to high thermal budget required for nucleation, while the second Ag nanocrystal plane is formed during a subsequent implantation due to the high diffusivity of Ag in silica. The aim of this work is to show how it is possible to overcome the limitation related to ion mixing and implantation damage to obtain double layers of Si-NCs and Ag-NCs with controlled characteristics. For this, we take advantage of annealing under slight oxidizing ambient to control the oxidation of Si-NCs and the Si excess in the matrix. The nanocrystal characteristics and in particular their position and size can be adjusted thanks to a compromise between the implantation energy, the implanted dose for both Si and Ag ions and the intermediate annealing conditions (atmosphere, temperature and duration).
Status and Applications of Diamond and Diamond-Like Materials: An Emerging Technology
1990-04-30
solar -blind detectors. * Modulated structures incorporating layers of BN and diamond, for example, to develop materials that are harder and/or tougher...hundredfold increase in power capability over silicon transistors. e Solar -blind detectors, which take advantage of the large energy gap (greater than...Some success has already been achieved, for example, in applying diamond-like coatings to ZnS and ZnSe windows using a Ge-C intermediate layer . " Anti
Changing Coastal oceanography of the Black Sea. I: Northwestern Shelf
NASA Astrophysics Data System (ADS)
Tolmazin, D.
This article describes the hydrography of the Northwestern Shelf (NWS), of the Black Sea emphasizing the changes induced by water management in the Dniejer and Dniester river basins. The existing literature and previously unpublished data have been reviewed and synthesized to describe water property fields and transport mechanisms of the NWS and the Dnieper and Dniester estuaries before the early 1960s, or the so-called precontrol period, when the effect of artificial river flow control upon the coastal waters was insignificant. After the hydroenergy complexes and water withdrawal and disposal systems on rivers became fully operational in the early 1970s (the so-called postcontrol period), the annual river discharge from the Dnieper and Dniester had noticeably decreased and seasonal river flow patterns had been artificially modified. Instead of a powerful and short early spring flood, typical for the natural conditions in the Dnieper river, the hydrographs in the postcontrol period exhibit two smaller peaks of river discharge of much longer period. One of them (winter-early spring) is caused by intense hydroenergy generation and weir discharges through the cascade of storage reservoirs. Another is associated with spring flood, modified by intense water consumption and storage in this period. High average river discharge in late May-early June strengthened the summer pycnocline which inhibits vertical mixing in the estuaries and coastal waters. Owing to a slow summer circulation, the rate of natural purification of the entire coastal system has been reduced. This coupled with the increased nutrient, organic and pollutant transport, decreased the dissolved-oxygen concentration and led to anoxic events and mass mortalities of marine organisms in the previously productive regions. These effects have primarily plagued the benthic communities along the entire western coast of the NWS since 1973. Winter convective overturn in the Black Sea reaches its maximum depth at the southern boundary of the NWS. Thus, the NWS waters descend beneath the seasonal and main thermoclines in the open sea and are spread by the prevailing currents across the entire sea in the cold intermediate layer (CIL). By this dynamic mechanism the projected man-made modifications in the riverine-estuarine systems of the NWS will affect and change the large-scale thermohaline structure and marine life of the Black Sea.
NASA Astrophysics Data System (ADS)
Ali, Syed M.; Bonnier, Franck; Tfayli, Ali; Lambkin, Helen; Flynn, Kathleen; McDonagh, Vincent; Healy, Claragh; Clive Lee, T.; Lyng, Fiona M.; Byrne, Hugh J.
2013-06-01
Raman spectroscopy coupled with K-means clustering analysis (KMCA) is employed to elucidate the biochemical structure of human skin tissue sections and the effects of tissue processing. Both hand and thigh sections of human cadavers were analyzed in their unprocessed and formalin-fixed, paraffin-processed (FFPP), and subsequently dewaxed forms. In unprocessed sections, KMCA reveals clear differentiation of the stratum corneum (SC), intermediate underlying epithelium, and dermal layers for sections from both anatomical sites. The SC is seen to be relatively rich in lipidic content; the spectrum of the subjacent layers is strongly influenced by the presence of melanin, while that of the dermis is dominated by the characteristics of collagen. For a given anatomical site, little difference in layer structure and biochemistry is observed between samples from different cadavers. However, the hand and thigh sections are consistently differentiated for all cadavers, largely based on lipidic profiles. In dewaxed FFPP samples, while the SC, intermediate, and dermal layers are clearly differentiated by KMCA of Raman maps of tissue sections, the lipidic contributions to the spectra are significantly reduced, with the result that respective skin layers from different anatomical sites become indistinguishable. While efficient at removing the fixing wax, the tissue processing also efficiently removes the structurally similar lipidic components of the skin layers. In studies of dermatological processes in which lipids play an important role, such as wound healing, dewaxed samples are therefore not appropriate. Removal of the lipids does however accentuate the spectral features of the cellular and protein components, which may be more appropriate for retrospective analysis of disease progression and biochemical analysis using tissue banks.
NASA Astrophysics Data System (ADS)
Kuang, Yubin; Stork, David G.; Kahl, Fredrik
2011-03-01
Underdrawings and pentimenti-typically revealed through x-ray imaging and infrared reflectography-comprise important evidence about the intermediate states of an artwork and thus the working methods of its creator.1 To this end, Shahram, Stork and Donoho introduced the De-pict algorithm, which recovers layers of brush strokes in paintings with open brush work where several layers are partially visible, such as in van Gogh's Self portrait with a grey felt hat.2 While that preliminary work served as a proof of concept that computer image analytic methods could recover some occluded brush strokes, the work needed further refinement before it could be a tool for art scholars. Our current work makes several steps to improve that algorithm. Specifically, we refine the inpainting step through the inclusion of curvature-based constraints, in which a mathematical curvature penalty biases the reconstruction toward matching the artist's smooth hand motion. We refine and test our methods using "ground truth" image data: passages of four layers of brush strokes in which the intermediate layers were recorded photographically. At each successive top layer (currently identified by the user), we used k-means clustering combined with graph cuts to obtain chromatically and spatially coherent segmentation of brush strokes. We then reconstructed strokes at the deeper layer with our new curvature-based inpainting algorithm based on chromatic level lines. Our methods are clearly superior to previous versions of the De-pict algorithm on van Gogh's works giving smoother, natural strokes that more closely match the shapes of unoccluded strokes. Our improved method might be applied to the classic drip paintings of Jackson Pollock, where the drip work is more open and the physics of splashing paint ensures that the curvature more uniform than in the brush strokes of van Gogh.
Meso-modeling of Carbon Fiber Composite for Crash Safety Analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lin, Shih-Po; Chen, Yijung; Zeng, Danielle
2017-04-06
In the conventional approach, the material properties for crash safety simulations are typically obtained from standard coupon tests, where the test results only provide single layer material properties used in crash simulations. However, the lay-up effects for the failure behaviors of the real structure were not considered in numerical simulations. Hence, there was discrepancy between the crash simulations and experimental tests. Consequently, an intermediate stage is required for accurate predictions. Some component tests are required to correlate the material models in the intermediate stage. In this paper, a Mazda Tube under high-impact velocity is chosen as an example for themore » crash safety analysis. The tube consists of 24 layers of uni-directional (UD) carbon fiber composite materials, in which 4 layers are perpendicular to, while the other layers are parallel to the impact direction. An LS-DYNA meso-model was constructed with orthotropic material models counting for the single-layer material behaviors. Between layers, a node-based tie-break contact was used for modeling the delamination of the composite material. Since fiber directions are not single-oriented, the lay-up effects could be an important effect. From the first numerical trial, premature material failure occurred due to the use of material parameters obtained directly from the coupon tests. Some parametric studies were conducted to identify the cause of the numerical instability. The finding is that the material failure strength used in the numerical model needs to be enlarged to stabilize the numerical model. Some hypothesis was made to provide the foundation for enlarging the failure strength and the corresponding experiments will be conducted to validate the hypothesis.« less
Study of iron deposit using seismic refraction and resistivity in Carajás Mineral Province, Brazil
NASA Astrophysics Data System (ADS)
Nogueira, Pedro Vencovsky; Rocha, Marcelo Peres; Borges, Welitom Rodrigues; Silva, Adalene Moreira; Assis, Luciano Mozer de
2016-10-01
This work comprises the acquisition, processing and interpretation of 2D seismic shallow refraction (P-wave) and resistivity profiles located in the iron ore deposit of N4WS, Carajás Mineral Province (CMP), northern Brazil. The geophysical methods were used to identify the boundaries of the iron ore deposit. Another objective was to evaluate the potentiality of these geophysical methods in that geological context. In order to validate the results, the geophysical lines were located to match a geological borehole line. For the seismic refraction, we used 120 channels, spaced by 10 m, in a line of 1190 m, with seven shot points. The resistivity method used in the acquisition was the electrical resistivity imaging, with pole-pole array, in order to reach greater depths. The resistivity line had a length of 1430 m, with 10 m spacing between electrodes. The seismic results produced a model with two distinct layers. Based on the velocities values, the first layer was interpreted as altered rocks, and the second layer as more preserved rocks. It was not possible to discriminate different lithologies with the seismic method inside each layer. From the resistivity results, a zone of higher resistivity (> 3937 Ω·m) was interpreted as iron ore, and a region of intermediate resistivity (from 816 to 2330 Ω·m) as altered rocks. These two regions represent the first seismic layer. On the second seismic layer, an area with intermediated resistivity values (from 483 to 2330 Ω·m) was interpreted as mafic rocks, and the area with lower resistivity (< 483 Ω·m) as jaspilite. Our results were compared with geological boreholes and show reasonable correlation, suggesting that the geophysical anomalies correspond to the main variations in composition and physical properties of rocks.
Mairet-Coello, Georges; Tury, Anna; Van Buskirk, Elise; Robinson, Kelsey; Genestine, Matthieu; DiCicco-Bloom, Emanuel
2012-01-01
During cerebral cortex development, precise control of precursor cell cycle length and cell cycle exit is required for balanced precursor pool expansion and layer-specific neurogenesis. Here, we defined the roles of cyclin-dependent kinase inhibitor (CKI) p57KIP2, an important regulator of G1 phase, using deletion mutant mice. Mutant mice displayed macroencephaly associated with cortical hyperplasia during late embryogenesis and postnatal development. Embryonically, proliferation of radial glial cells (RGC) and intermediate precursors (IPC) was increased, expanding both populations, with greater effect on IPCs. Furthermore, cell cycle re-entry was increased during early corticogenesis, whereas cell cycle exit was augmented at middle stage. Consequently, neurogenesis was reduced early, whereas it was enhanced during later development. In agreement, the timetable of early neurogenesis, indicated by birthdating analysis, was delayed. Cell cycle dynamics analyses in mutants indicated that p57KIP2 regulates cell cycle length in both RGCs and IPCs. By contrast, related CKI p27KIP1 controlled IPC proliferation exclusively. Furthermore, p57KIP2 deficiency markedly increased RGC and IPC divisions at E14.5, whereas p27KIP1 increased IPC proliferation at E16.5. Consequently, loss of p57KIP2 increased primarily layer 5-6 neuron production, whereas loss of p27KIP1 increased neurons specifically in layers 2-5. In conclusion, our observations suggest that p57KIP2 and p27KIP1 control neuronal output for distinct cortical layers by regulating different stages of precursor proliferation, and support a model in which IPCs contribute to both lower and upper layer neuron generation. PMID:22223678
NASA Astrophysics Data System (ADS)
Bensi, Manuel; Velaoras, Dimitris; Cardin, Vanessa; Perivoliotis, Leonidas; Pethiakis, George
2015-04-01
Long-term variations of temperature and salinity observed in the Adriatic and Aegean Seas seem to be regulated by larger-scale circulation modes of the Eastern Mediterranean (EMed) Sea, such as the recently discovered feedback mechanisms, namely the BiOS (Bimodal Oscillating System) and the internal thermohaline pump theories. These theories are the results of interpretation of many years' observations, highlighting possible interactions between two key regions of the EMed. Although repeated oceanographic cruises carried out in the past or planned for the future are a very useful tool for understanding the interaction between the two basins (e.g. alternating dense water formation, salt ingressions), recent long time-series of high frequency (up to 1h) sampling have added valuable information to the interpretation of internal mechanisms for both areas (i.e. mesoscale eddies, evolution of fast internal processes, etc.). During the last 10 years, three deep observatories were deployed and maintained in the Adriatic, Ionian, and Aegean Seas: they are respectively, the E2-M3A, the Pylos, and the E1-M3A. All are part of the largest European network of Fixed Point Open Ocean Observatories (FixO3, http://www.fixo3.eu/). Herein, from the analysis of temperature and salinity, and potential density time series collected at the three sites from the surface down to the intermediate and deep layers, we will discuss the almost perfect anti-correlated behavior between the Adriatic and the Aegean Seas. Our data, collected almost continuously since 2006, reveal that these observatories well represent the thermohaline variability of their own areas. Interestingly, temperature and salinity in the intermediate layer suddenly increased in the South Adriatic from the end of 2011, exactly when they started decreasing in the Aegean Sea. Moreover, Pylos data used together with additional ones (e.g. Absolute dynamic topography, temperature and salinity data from other platforms) collected along the typical pathway of the Levantine/Cretan intermediate waters towards the Adriatic Sea, reveal variability of the subsurface/intermediate layers (100-400m depth), which could possibly be attributed to seasonal variability or influences from dynamical features such as the Pelops Gyre. References Bensi, M., V. Cardin, A. Rubino, G. Notarstefano, and P. M. Poulain (2013), Effects of winter convection on the deep layer of the Southern Adriatic Sea in 2012, J. Geophys. Res. Oceans, 118, doi:10.1002/2013JC009432. Velaoras, D., G. Krokos, K. Nittis, and A. Theocharis (2014), Dense intermediate water outflow from the Cretan Sea: A salinity driven, recurrent phenomenon, connected to thermohaline circulation changes, J. Geophys. Res. Oceans, 119, doi:10.1002/2014JC009937.
School Climate, Discrimination, and Depressive Symptoms among Asian American Adolescents
ERIC Educational Resources Information Center
Wang, Cixin; Atwal, Kavita
2015-01-01
The current study examined a multidimensional, developmental, and transactional model for depressive symptoms among Asian American adolescents using longitudinal data from 1,664 Asian American adolescents in the Children of Immigrants Longitudinal Study (CILS). Specifically, the relationships among school climate, acculturation, perceived…
34 CFR 364.2 - What is the purpose of the programs authorized by chapter 1 of title VII?
Code of Federal Regulations, 2013 CFR
2013-07-01
... SILS and CIL programs authorized by chapter 1 of title VII of the Act is to promote a philosophy of independent living (IL), including a philosophy of consumer control, peer support, self-help, self...
34 CFR 364.2 - What is the purpose of the programs authorized by chapter 1 of title VII?
Code of Federal Regulations, 2014 CFR
2014-07-01
... SILS and CIL programs authorized by chapter 1 of title VII of the Act is to promote a philosophy of independent living (IL), including a philosophy of consumer control, peer support, self-help, self...
34 CFR 364.2 - What is the purpose of the programs authorized by chapter 1 of title VII?
Code of Federal Regulations, 2012 CFR
2012-07-01
... SILS and CIL programs authorized by chapter 1 of title VII of the Act is to promote a philosophy of independent living (IL), including a philosophy of consumer control, peer support, self-help, self...
75 FR 39529 - Ocean Transportation Intermediary License Applicants
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-09
...), Adam Karabashi, Secretary, Application Type: Add NVO Service and Trade Name Change Blue Ocean Shipping...: Trade Name Change Chemlogix Global LLC dba Vistalogix Global (OFF & NVO), 1777 Sentry Parkway West... Individual), John S. Hamilton, Manager/Chairman/CEO, Application Type: Trade Name Change CIL Freight Inc...
Strategic planning for skills and simulation labs in colleges of nursing.
Gantt, Laura T
2010-01-01
While simulation laboratories for clinical nursing education are predicted to grow, budget cuts may threaten these programs. One of the ways to develop a new lab, as well as to keep an existing one on track, is to develop and regularly update a strategic plan. The process of planning not only helps keep the lab faculty and staff apprised of the challenges to be faced, but it also helps to keep senior level management engaged by reason of the need for their input and approval of the plan. The strategic planning documents drafted by those who supervised the development of the new building and Concepts Integration Labs (CILs) helped guide and orient faculty and other personnel hired to implement the plan and fulfill the vision. As the CILs strategic plan was formalized, the draft plans, including the SWOT analysis, were reviewed to provide historical perspective, stimulate discussion, and to make sure old or potential mistakes were not repeated.
NASA Technical Reports Server (NTRS)
Gotch, S. M.
1986-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NAA FMEA/CIL documentation. The independent analysis results corresponding to the Orbiter Electrical Power Generation (EPG)/Power Reactants Storage and Distribution (PRSD) System Hardware is documented. The EPG/PRSD hardware is required for performing critical functions of cryogenic hydrogen and oxygen storage and distribution to the Fuel Cell Powerplants (FCP) and Atmospheric Revitalization Pressure Control Subsystem (ARPCS). Specifically, the EPG/PRSD hardware consists of the following: Hydryogen (H2) tanks; Oxygen (O2) tanks; H2 Relief Valve/Filter Packages (HRVFP); O2 Relief Valve/Filter Packages (ORVFP); H2 Valve Modules (HVM); O2 Valve Modules (OVM); and O2 and H2 lines, components, and fittings.
NASA Technical Reports Server (NTRS)
Saiidi, M. J.; Duffy, R. E.; Mclaughlin, T. D.
1986-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis/Critical Items List (FMEA/CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The independent analysis results corresponding to the Orbiter Atmospheric Revitalization and Pressure Control Subsystem (ARPCS) are documented. The ARPCS hardware was categorized into the following subdivisions: (1) Atmospheric Make-up and Control (including the Auxiliary Oxygen Assembly, Oxygen Assembly, and Nitrogen Assembly); and (2) Atmospheric Vent and Control (including the Positive Relief Vent Assembly, Negative Relief Vent Assembly, and Cabin Vent Assembly). The IOA analysis process utilized available ARPCS hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.
Independent Orbiter Assessment (IOA): Analysis of the mechanical actuation subsystem
NASA Technical Reports Server (NTRS)
Bacher, J. L.; Montgomery, A. D.; Bradway, M. W.; Slaughter, W. T.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Mechanical Actuation System (MAS) hardware. Specifically, the MAS hardware consists of the following components: Air Data Probe (ADP); Elevon Seal Panel (ESP); External Tank Umbilical (ETU); Ku-Band Deploy (KBD); Payload Bay Doors (PBD); Payload Bay Radiators (PBR); Personnel Hatches (PH); Vent Door Mechanism (VDM); and Startracker Door Mechanism (SDM). The IOA analysis process utilized available MAS hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.
ERIC Educational Resources Information Center
Greenman, Geri
2000-01-01
Describes the first assignment for an intermediate oil painting class in which the students painted the human figure. Explains that the assignment involved three techniques: (1) abstract application of acrylic paint; (2) oil "Paintstiks" from Shiva; and (3) a final layer of actual oil paint. (CMK)
Popovi, Miroljub; Caballero-Bleda, María; Kadish, Inga; van Groen, Thomas
2008-01-01
The depletion of neuronal calcium binding proteins deprives neurons of the capacity to buffer high levels of intracellular Ca2+ and this leaves them vulnerable to pathological processes, such as those present in Alzheimer’s disease (AD). The aim of the present study was to investigate the expression of the calcium binding proteins, calbindin-D28K, calretinin and parvalbumin in the dentate gyrus (DG) of APP/PS1 transgenic mice and their non-Tg littermates, as well as the relation with the deposition of human Aβ. We measured the expression of these three proteins at seven different rostro-caudal levels, and in the molecular, granular and polymorphic layers of the DG. We found that, except in the most caudal part of the DG, there is a substantial loss of calbindin-D28K immunoreactivity in all three layers of the DG in APP/PS1 mice compared to the non-Tg mice. Significant loss of calretinin immunoreactivity is present in most of the polymorphic layer of the DG of APP/PS1 mice compared to the non-Tg mice, as well as in the rostral and intermediate part of the inner molecular layer. Compared to the non-Tg mice parvalbumin immunoreactivity is significantly reduced throughout the whole polymorphic layer as well as in the rostral and intermediate part of the granular layer of DG in APP/PS1 mice. The relatively preservation of calbindin immunoreactivity in the caudal part of molecular and granular layers as well as calretinin immunoreactivity in the caudal part of polymorphic layer of the DG is likely related to the lower Aβ expression in those parts of DG. The present data suggest an involvement of calcium-dependent pathways in the pathogenesis of AD and indicate that there exists a subfield and layer-specific decrease in immunoreactivity which is related to the type of calcium-binding protein in APP/PS1 mice. Moreover, it seems that APP expression affects more the calbindin expression then parvalbumin and calretinin expression in the DG of APP/PS1 transgenic mice. PMID:18583063
The expansion of polarization charge layers into magnetized vacuum - Theory and computer simulations
NASA Technical Reports Server (NTRS)
Galvez, Miguel; Borovsky, Joseph E.
1991-01-01
The formation and evolution of polarization charge layers on cylindrical plasma streams moving in vacuum are investigated using analytic theory and 2D electrostatic particle-in-cell computer simulations. It is shown that the behavior of the electron charge layer goes through three stages. An early time expansion is driven by electrostatic repulsion of electrons in the charge layer. At the intermediate stage, the simulations show that the electron-charge-layer expansion is halted by the positively charged plasma stream. Electrons close to the stream are pulled back to the stream and a second electron expansion follows in time. At the late stage, the expansion of the ion charge layer along the magnetic field lines accompanies the electron expansion to form an ambipolar expansion. It is found that the velocities of these electron-ion expansions greatly exceed the velocities of ambipolar expansions which are driven by plasma temperatures.
Multilayer article having stabilized zirconia outer layer and chemical barrier layer
NASA Technical Reports Server (NTRS)
Bansal, Narottam P. (Inventor); Lee, Kang N. (Inventor)
2004-01-01
A multilayer article includes a substrate that includes at least one of a ceramic compound and a Si-containing metal alloy. An outer layer includes stabilized zirconia. Intermediate layers are located between the outer layer and the substrate and include a mullite-containing layer and a chemical barrier layer. The mullite-containing layer includes 1) mullite or 2) mullite and an alkaline earth metal aluminosilicate. The chemical barrier layer is located between the mullite-containing layer and the outer layer. The chemical barrier layer includes at least one of mullite, hafnia, hafnium silicate and rare earth silicate (e.g., at least one of RE.sub.2 SiO.sub.5 and RE.sub.2 Si.sub.2 O.sub.7 where RE is Sc or Yb). The multilayer article is characterized by the combination of the chemical barrier layer and by its lack of a layer consisting essentially of barium strontium aluminosilicate between the mullite-containing layer and the chemical barrier layer. Such a barium strontium aluminosilicate layer may undesirably lead to the formation of a low melting glass or unnecessarily increase the layer thickness with concomitant reduced durability of the multilayer article. In particular, the chemical barrier layer may include at least one of hafnia, hafnium silicate and rare earth silicate.
Effect of Intermediate Flush Using Different Devices to Prevent Chemical Smear Layer Formation.
Silva, Camilla Corrêa; Ferreira, Vivian Maria Durange; De-Deus, Gustavo; Herrera, Daniel Rodrigo; Prado, Maíra do; Silva, Emmanuel João Nogueira Leal da
2017-01-01
This study compared the effect of intermediate flush with distilled water delivered by conventional irrigation, EndoVac microcannula or Self-Adjusting File (SAF) system in the prevention of chemical smear layer (CSL) formation. Thirty human premolars were used. Canals were prepared with Reciproc system and 5.25% NaOCl. After chemomechanical preparation, samples were divided in 3 groups (n=10) according to the intermediate irrigation protocol with distilled water using: conventional irrigation, EndoVac microcannula or SAF. A final flush with 2% chlorhexidine solution was used and scanning electron microscopy was performed to assess protocol effectiveness. Two calibrated evaluators attributed scores according the presence or absence of CSL on the surface of the root canal walls at the coronal, middle and apical thirds, as follows: (1) no CSL; (2) small amounts of CSL; (3) moderate CSL; and (4) heavy CSL. Differences between protocols were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Friedman and Wilcoxon signed rank tests were used for comparison between each root canal third. SAF resulted in less formation of CSL when compared with the conventional irrigation and EndoVac microcannula (p<0.05). When root canal thirds were analyzed, conventional irrigation and EndoVac groups showed less CSL formation at coronal and middle thirds in comparison to the apical third (p<0.05). In SAF group, there was no difference among the thirds (p>0.05). It may be concluded that an intermediate flush of distilled water, delivered by the SAF system resulted in a better reduction of CSL formation during chemomechanical preparation.
Herzing, Andrew A; Ro, Hyun Wook; Soles, Christopher L; DeLongchamp, Dean M
2013-09-24
The morphology of the active layer in an organic photovoltaic bulk-heterojunction device is controlled by the extent and nature of phase separation during processing. We have studied the effects of fullerene crystallinity during heat treatment in model structures consisting of a layer of poly(3-hexylthiophene) (P3HT) sandwiched between two layers of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). Utilizing a combination of focused ion-beam milling and energy-filtered transmission electron microscopy, we monitored the local changes in phase distribution as a function of annealing time at 140 °C. In both cases, dissolution of PCBM within the surrounding P3HT was directly visualized and quantitatively described. In the absence of crystalline PCBM, the overall phase distribution remained stable after intermediate annealing times up to 60 s, whereas microscale PCBM aggregates were observed after annealing for 300 s. Aggregate growth proceeded vertically from the substrate interface via uptake of PCBM from the surrounding region, resulting in a large PCBM-depleted region in their vicinity. When precrystallized PCBM was present, amorphous PCBM was observed to segregate from the intermediate P3HT layer and ripen the crystalline PCBM underneath, owing to the far lower solubility of crystalline PCBM within P3HT. This process occurred rapidly, with segregation already evident after annealing for 10 s and with uptake of nearly all of the amorphous PCBM by the crystalline layer after 60 s. No microscale aggregates were observed in the precrystallized system, even after annealing for 300 s.
What Hands May Tell Us about Reading and Writing
ERIC Educational Resources Information Center
Mangen, Anne
2016-01-01
Reading and writing are increasingly performed with digital, screen-based technologies rather than with analogue technologies such as paper and pen(cil). The current digitization is an occasion to "unpack," theoretically and conceptually, what is entailed in reading and writing as embodied, multisensory processes involving audiovisual…
Lauf, Robert J.; Hoffheins, Barbara S.; Fleming, Pamela H.
1994-01-01
A hydrogen sensor element comprises an essentially inert, electrically-insulating substrate having a thin-film metallization deposited thereon which forms at least two resistors on the substrate. The metallization comprises a layer of Pd or a Pd alloy for sensing hydrogen and an underlying intermediate metal layer for providing enhanced adhesion of the metallization to the substrate. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors, and at least one of the resistors is left uncovered. The difference in electrical resistances of the covered resistor and the uncovered resistor is related to hydrogen concentration in a gas to which the sensor element is exposed.
Lauf, R.J.; Hoffheins, B.S.; Fleming, P.H.
1994-11-22
A hydrogen sensor element comprises an essentially inert, electrically-insulating substrate having a thin-film metallization deposited thereon which forms at least two resistors on the substrate. The metallization comprises a layer of Pd or a Pd alloy for sensing hydrogen and an underlying intermediate metal layer for providing enhanced adhesion of the metallization to the substrate. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors, and at least one of the resistors is left uncovered. The difference in electrical resistances of the covered resistor and the uncovered resistor is related to hydrogen concentration in a gas to which the sensor element is exposed. 6 figs.
Advanced Antireflection Coatings for High-Performance Solar Energy Applications
NASA Technical Reports Server (NTRS)
Pan, Noren
2015-01-01
Phase II objectives: Develop and refine antireflection coatings incorporating lanthanum titanate as an intermediate refractive index material; Investigate wet/dry thermal oxidation of aluminum containing semiconductor compounds as a means of forming a more transparent window layer with equal or better optical properties than its unoxidized form; Develop a fabrication process that allows integration of the oxidized window layer and maintains the necessary electrical properties for contacting the solar cell; Conduct an experimental demonstration of the best candidates for improved antireflection coatings.
NASA Astrophysics Data System (ADS)
Djordjevich, Alexandar; Simović, Ana; Savović, Svetislav; Drljača, Branko
2018-07-01
Infrared wavelength dependence of leaky mode losses and steady state distribution (SSD) in W-type glass optical fibers (doubly clad fibers with three layers) is investigated in this paper for parametrically varied depths and widths of the fiber's intermediate optical layer. This enables a tailoring of configuration of the W-type fiber to suit an application at hand. We have shown that the proposed W-type fiber has better transmission characteristics at longer infrared wavelengths.
Simple functionalization method for single conical pores with a polydopamine layer
NASA Astrophysics Data System (ADS)
Horiguchi, Yukichi; Goda, Tatsuro; Miyahara, Yuji
2018-04-01
Resistive pulse sensing (RPS) is an interesting analytical system in which micro- to nanosized pores are used to evaluate particles or small analytes. Recently, molecular immobilization techniques to improve the performance of RPS have been reported. The problem in functionalization for RPS is that molecular immobilization by chemical reaction is restricted by the pore material type. Herein, a simple functionalization is performed using mussel-inspired polydopamine as an intermediate layer to connect the pore material with functional molecules.
Ca, Nguyen Xuan; Lien, V T K; Nghia, N X; Chi, T T K; Phan, The-Long
2015-11-06
We used wet chemical methods to synthesize core-shell nanocrystalline samples CdS(d)/ZnSe N , where d = 3-6 nm and N = 1-5 are the size of CdS cores and the number of monolayers grown on the cores, respectively. By annealing typical CdS(d)/ZnSe N samples (with d = 3 and 6 nm and N = 2) at 300 °C for various times t an = 10-600 min, we created an intermediate layer composed of Zn1-x Cd x Se and Cd1-x Zn x S alloys with various thicknesses. The formation of core-shell structures and intermediate layers was monitored by Raman scattering and UV-vis absorption spectrometers. Careful photoluminescence studies revealed that the as-prepared CdS(d)/ZnSe N samples with d = 5 nm and N = 2-4, and the annealed samples CdS(3 nm)/ZnSe2 with t an ≤ 60 min and CdS(6 nm)/ZnSe2 with t an ≤ 180 min, show the emission characteristics of type-II systems. Meanwhile, the other samples show the emission characteristics of type-I systems. These results prove that the partial separation of photoexcited carriers between the core and shell is dependent strongly on the engineered core-shell nanostructures, meaning the sizes of the core, shell, and intermediate layers. With the tunable luminescence properties, CdS-ZnSe-based core-shell materials are considered as promising candidates for multiple-exciton generation and single-photon sources.
NASA Astrophysics Data System (ADS)
Chou, Bang-Yen; Chang, Edward
2003-06-01
Hydroxyapatite coatings were plasma sprayed on the Ti6A14V substrate with and without an intermediate ZrO2 layer; meanwhile the temperatures of substrates were varied at 90, 140, and 200 °C. The coatings were subjected to the standard adhesion test per ASTM C633-79. The purpose of the investigation was to study the effects of those processing variables on the bonding strength and failure behavior of the system. It is found that the bonding strengths of HA/ZrO2 and HA coatings generally decrease with increasing substrate temperature, except for the HA/ZrO2 coating deposited at 200 °C. The rationale of the results is attributed to the residual stress reported in the literature. Introducing ZrO2 bond coat is found to significantly promote the bonding strength of HA coating. The possible strengthening mechanism is the rougher surface of ZrO2 bond coat and the higher toughness of ZrO2, which provide the mechanical strengthening effects. The slightly denser HA in 200 °C deposited HA coating cannot explain the high bonding strength of the HA/ZrO2 coating, nor the mechanical strengthening effect of ZrO2 intermediate layer should apply. It is believed that a stronger diffusion bonding is formed at the interface of HA and ZrO2, which increases the bonding between them chemically. The bonding strengths of HA/ZrO2 and HA coatings are correlated with the area fraction of adhesive failure of the coatings. The correlation explains the findings in this study.
Phonon exchange by two-dimensional electrons in intermediate magnetic fields
NASA Astrophysics Data System (ADS)
Gopalakrishnan, Gokul
The discovery of the integer and fractional quantum Hall effects have broadened the exploration of the two-dimensional electron gas to regimes where complex and exciting physics lay previously hidden. While many experimental investigations have focused on the regime of large magnetic fields where transport properties are determined by contributions from a single Landau level, the regime of intermediate fields, where multiple Landau levels are involved, has been much less explored. This dissertation is a report on a previously unobserved interaction probed by a novel type of magneto-transport measurement performed in this intermediate regime, in bilayer two-dimensional electron systems. This measurement technique, known as electron drag, directly measures interlayer electron-electron scattering rates, by measuring the voltage induced in one of the layers when a current is driven through the other. The scattering mechanism, which may be Coulomb or phonon mediated, depends critically on both the separation between the layers and the electron density. When electron drag is measured in the presence of a perpendicular magnetic field in suitable samples, the resulting magnetodrag signal reveals new information about the electronic states as well as properties of a phonon mediated scattering mechanism. This phonon scattering mechanism is reflected in previously unobserved oscillations. These oscillations, which are periodic in the inverse field, are argued to arise from a resonant interlayer exchange of 2 kF phonons. Measurements of the temperature, density and layer-spacing dependences of magnetodrag resistivity are reported and are shown to confirm this particular mechanism. Additionally, analysis of the temperature dependence reveals a strong sensitivity to Landau level widths. Based on this analysis, a means of characterizing the broadening of Landau levels and hence, electronic lifetimes in this regime, which are otherwise difficult to characterize, is proposed.
Improvement of perpendicular anisotropy of columnar FePt-ZrO2-C films with FePt insert layer
NASA Astrophysics Data System (ADS)
Dong, Kaifeng; Mo, Wenqin; Jin, Fang; Song, Junlei; Cheng, Weimin; Wang, Haiwei
2018-05-01
The effects of various thicknesses of FePt insert layer on the microstructure and magnetic properties of FePt-ZrO2-C thin films have been investigated. It is found that with inserting 0.4 nm FePt films between the TiON intermediate layer and FePt-ZrO2-C layer, the perpendicular anisotropy indicated by Hc⊥/Hc//ratio would increase from 4 to 13.1, suggesting the perpendicular anisotropy could be improved a lot with using FePt insert layer. Simultaneously, the FePt grains of FePt-ZrO2-C thin films maintained columnar structure and the grain isolation could also be improved in a certain degree. With further increase of the FePt insert layer thickness, although the perpendicular anisotropy was still larger than that without FePt insert layer, the grain size of the FePt-ZrO2-C films would increase and the isolation would be deteriorated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shearer, Melinda J.; Samad, Leith; Zhang, Yi
The interesting and tunable properties of layered metal dichalcogenides heavily depend on their phase and layer stacking. Here, we show and explain how the layer stacking and physical properties of WSe 2 are influenced by screw dislocations. A one-to-one correlation of atomic force microscopy and high- and low-frequency Raman spectroscopy of many dislocated WSe 2 nanoplates reveals variations in the number and shapes of dislocation spirals and different layer stackings that are determined by the number, rotation, and location of the dislocations. Plates with triangular dislocation spirals form noncentrosymmetric stacking that gives rise to strong second-harmonic generation and enhanced photoluminescence,more » plates with hexagonal dislocation spirals form the bulk 2H layer stacking commonly observed, and plates containing mixed dislocation shapes have intermediate noncentrosymmetric stackings with mixed properties. Multiple dislocation cores and other complexities can lead to more complex stackings and properties. Finally, these previously unobserved properties and layer stackings in WSe 2 will be interesting for spintronics and valleytronics.« less
Shearer, Melinda J.; Samad, Leith; Zhang, Yi; ...
2017-02-08
The interesting and tunable properties of layered metal dichalcogenides heavily depend on their phase and layer stacking. Here, we show and explain how the layer stacking and physical properties of WSe 2 are influenced by screw dislocations. A one-to-one correlation of atomic force microscopy and high- and low-frequency Raman spectroscopy of many dislocated WSe 2 nanoplates reveals variations in the number and shapes of dislocation spirals and different layer stackings that are determined by the number, rotation, and location of the dislocations. Plates with triangular dislocation spirals form noncentrosymmetric stacking that gives rise to strong second-harmonic generation and enhanced photoluminescence,more » plates with hexagonal dislocation spirals form the bulk 2H layer stacking commonly observed, and plates containing mixed dislocation shapes have intermediate noncentrosymmetric stackings with mixed properties. Multiple dislocation cores and other complexities can lead to more complex stackings and properties. Finally, these previously unobserved properties and layer stackings in WSe 2 will be interesting for spintronics and valleytronics.« less
NASA Astrophysics Data System (ADS)
Singh, Abhishek Kumar; Das, Amrita; Parween, Zeenat; Chattopadhyay, Amares
2015-10-01
The present paper deals with the propagation of Love-type wave in an initially stressed irregular vertically heterogeneous layer lying over an initially stressed isotropic layer and an initially stressed isotropic half-space. Two different types of irregularities, viz., rectangular and parabolic, are considered at the interface of uppermost initially stressed heterogeneous layer and intermediate initially stressed isotropic layer. Dispersion equations are obtained in closed form for both cases of irregularities, distinctly. The effect of size and shape of irregularity, horizontal compressive initial stress, horizontal tensile initial stress, heterogeneity of the uppermost layer and width ratio of the layers on phase velocity of Love-type wave are the major highlights of the study. Comparative study has been made to identify the effects of different shapes of irregularity, presence of heterogeneity and initial stresses. Numerical computations have been carried out and depicted by means of graphs for the present study.
Reflection of acoustic wave from the elastic seabed with an overlying gassy poroelastic layer
NASA Astrophysics Data System (ADS)
Chen, Weiyun; Wang, Zhihua; Zhao, Kai; Chen, Guoxing; Li, Xiaojun
2015-10-01
Based on the multiphase poroelasticity theory, the reflection characteristics of an obliquely incident acoustic wave upon a plane interface between overlying water and a gassy marine sediment layer with underlying elastic solid seabed are investigated. The sandwiched gassy layer is modelled as a porous material with finite thickness, which is saturated by two compressible and viscous fluids (liquid and gas). The closed-form expression for the amplitude ratio of the reflected wave, called reflection coefficient, is derived theoretically according to the boundary conditions at the upper and lower interfaces in our proposed model. Using numerical calculation, the influences of layer thickness, incident angle, wave frequency and liquid saturation of sandwiched porous layer on the reflection coefficient are analysed, respectively. It is revealed that the reflection coefficient is closely associated with incident angle and sandwiched layer thickness. Moreover, in different frequency ranges, the dependence of the wave reflection characteristics on moisture (or gas) variations in the intermediate marine sediment layer is distinguishing.
NASA Astrophysics Data System (ADS)
Arango-Galván, C.; Flores-Marquez, L. E.; Martínez-Serrano, R.
2009-12-01
New policies on the use of water resources in Mexico have led to implement some alternative measures to optimize water management. In particular, water regulation entities have recommended some tools to preserve and protect the groundwater supplies. One of these tools is the artificial recharge by injecting water directly into the aquifer. The main goal of this study is to assess if it is suitable to inject rainwater and surface water in a small portion of the aquifer of the city of Puebla, in central Mexico. Artificial aquifer recharging was evaluated using a numeric model, which simulated the physical properties of the system. The model setup was inferred from an integrated study taking into account hydraulic, geological and geophysical data. The geoelectrical model was computed using electric resistivity tomography (ERT) and time domain electromagnetic data (TDEM). The aquifer geological structure inferred from geophysics depicts the presence of a shallower layer composed of sand and clay deposits with low saturation and permeability. This layer contains silt lenses that can be controlling the persistence of small water bodies on surface. Some water surficial bodies seem to be isolated from the main aquifer system. The intermediate layer shows lower electrical resistivity and higher permeability. Underlying this horizon, it is a deeper layer that reaches 200 m depth, according to information obtained from borehole in the zone. This layer shows an electrical resistivity even lower than intermediate layer but low permeability, caused by the higher content of silts. Both of these layers are the shallower aquifer exploited in the area. Once the numeric model was built we proceeded to simulate scenarios that include the continued extraction and recharge of water in wells located in strategic areas of the study zone. The results suggest that the effect of infiltration is beneficial on aquifer recharge and reduces the cone of depression caused by the extraction. However, this remedial action will only have a positive effect if the extraction rate is adequate.
On Suspended matter grain size in Baltic sea
NASA Astrophysics Data System (ADS)
Bubnova, Ekaterina; Sivkov, Vadim; Zubarevich, Victor
2016-04-01
Suspended matter grain size data were gathered during the 25th research vessel "Akademik Mstislav Keldysh" cruise (1991, September-October). Initial quantitative data were obtained with a use of the Coulter counter and subsequently modified into volume concentrations (mm3/l) for size intervals. More than 80 samples from 15 stations were analyzed (depth range 0-355 m). The main goal of research was to illustrate the spatial variability of suspended matter concentration and dispersion in Baltic Sea. The mutual feature of suspended matter grain size distribution is the logical rise of particle number along with descending of particle's size. Vertical variability of grain size distribution was defined by Baltic Sea hydrological structure, including upper mixed layer - from the surface to the thermocline - with 35 m thick, cold intermediate layer - from the thermocline to the halocline- and bottom layer, which lied under the halocline. Upper layer showed a rise in total suspended matter concentration (up to 0.6 mm3/l), while cold intermediate level consisted of far more clear water (up to 0.1 mm3/l). Such a difference is caused by the thermocline boarding role. Meanwhile, deep bottom water experienced surges in suspended matter concentration owing to the nepheloid layer presence and "liquid bottom" effect. Coastal waters appeared to have the highest amount of particles (up to 5.0 mm3/l). Suspended matter grain size distribution in the upper mixed layer revealed a peak of concentration at 7 μ, which can be due to autumn plankton bloom. Another feature in suspended matter grain size distribution appeared at the deep layer below halocline, where both O2 and H2S were observed and red/ox barrier is. The simultaneous presence of Fe and Mn (in solutions below red/ox barrier) and O2 leads to precipitation of oxyhydrates Fe and Mn and grain size distribution graph peaking at 4.5 μ.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-15
... vocational rehabilitation (VR) agencies and agency partners that cooperate with State VR agencies in providing VR and other rehabilitation services (e.g., Centers for Independent Living (CILs), Client... following outcomes: Improved quality of VR services, increased effectiveness and efficiency of State VR...
JPRS Report, Soviet Union: Political Affairs
1988-02-23
conflicts and injustices. The system of "artistic coun- cils," "ratings," "authorization of lyrics ," etc., is based exclusively "on a subjective...its court essay , "A Fictitious Marriage and a Funeral Dress," told of this instance: S. Nevya- domskaya, a resident of Ordzhonikidze, having regis
Installation Restoration Program. Phase 2. Confirmation McClellan AFB, California. Volume 1
1983-06-01
testing in accordance with ASTH C 828-78 and in conformance with CAL/ OSHA safety orders and ES Industrial Sewer Entry Procedures. Indi- viduals entering...Liquid Palm Cil Wastes," Proceedings: Asia Acuatech, Singapore, Malaysia , March 1980 (Coauthors R. White and C. Ponniah). "Surface Impoundment of
NASA Technical Reports Server (NTRS)
Mar, A.; Dworkin, J.; Oro, J.
1987-01-01
Using urea and cyanamide, the two condensing agents considered to have been present on the primitive earth, uridine diphosphate glucose (UDPG), cytidine diphosphate choline (CDP-choline), glucose-1-phosphate (G1P), and glucose-6-phosphate (G6P) were synthesized under simulated prebiotic conditions. The reaction products were separated and identified using paper chromatography, thin layer chromatography, enzymatic analyses, and ion-pair reverse-phase high performance liquid chromatography. The possibility of nonenzymatic synthesis of metabolic intermediates on the primitive earth from simple precursors was thus demonstrated.
Commercial Scale Production of High Temperature
1991-11-14
Rochester, Professor Alan Kadin and his graduate students Derek Mallory and Patrick Borelli , have concentrated on microwave measurements and intermediate...layers. Patrick Borelli was responsible for the PLZT/YBCO work. The same personnel will be available for the second year of the contract. We spent our
Heat reflecting tape for thermoelectric converter
Purdy, David L.
1977-01-01
Threads are interlaced with thermoelectric wires to provide a woven cloth in tape form, there being an intermediate layer of heat radiation reflecting material (e.g., aluminum foil) insulated electrically from said wires, which are of opposite thermoelectric polarity and connected as a plurality of thermocouples.
NASA Astrophysics Data System (ADS)
A Lee, E.; Lee, S.; Hwang, H. J.; Moon, J.-W.
A ceramic coating technique is applied to reduce the voltage drop caused by oxidation of the metallic separator (SUS444) in intermediate-temperature (IT) solid oxide fuel cell (SOFCs) systems. Precursor solutions for (La, Ca)CrO 3 (LCC) and (La, Sr)CrO 3 (LSC) coatings are prepared by adding nitric acid and ethylene glycol into an aqueous solution of lanthanum, strontium (or calcium) and chromium nitrates. Dried LCC and LSC gel films are heat-treated at 400-800 °C after dip-coating on the SUS444 substrate. XRD and Fourier-transform infrared (FT-IR) analysis is used to examine the crystallization behaviour and chemical structure of the precursor solution. The oxidation behaviour of the coated SUS444 substrate is compared with an uncoated SUS444 substrate. The oxidation of the SUS444 is inhibited by the LCC and LSC thin film layers.
Mechanism of bonding and debonding using surface activated bonding method with Si intermediate layer
NASA Astrophysics Data System (ADS)
Takeuchi, Kai; Fujino, Masahisa; Matsumoto, Yoshiie; Suga, Tadatomo
2018-04-01
Techniques of handling thin and fragile substrates in a high-temperature process are highly required for the fabrication of semiconductor devices including thin film transistors (TFTs). In our previous study, we proposed applying the surface activated bonding (SAB) method using Si intermediate layers to the bonding and debonding of glass substrates. The SAB method has successfully bonded glass substrates at room temperature, and the substrates have been debonded after heating at 450 °C, in which TFTs are fabricated on thin glass substrates for LC display devices. In this study, we conducted the bonding and debonding of Si and glass in order to understand the mechanism in the proposed process. Si substrates are also successfully bonded to glass substrates at room temperature and debonded after heating at 450 °C using the proposed bonding process. By the composition analysis of bonding interfaces, it is clarified that the absorbed water on the glass forms interfacial voids and cause the decrease in bond strength.
Development of CVD-W coatings on CuCrZr and graphite substrates with a PVD intermediate layer
NASA Astrophysics Data System (ADS)
Song, Jiupeng; Lian, Youyun; Lv, Yanwei; Liu, Junyong; Yu, Yang; Liu, Xiang; Yan, Binyou; Chen, Zhigang; Zhuang, Zhigang; Zhao, Ximeng; Qi, Yang
2014-12-01
In order to apply tungsten (W) coatings by chemical vapor deposition (CVD) for repairing or updating the plasma facing components (PFCs) of the first wall and divertor in existing or future tokomaks, where CuCrZr or graphite is the substrate material, an intermediate layer by physical vapor deposition (PVD) has been used to accommodate the interface stress due to the mismatch of thermal expansion or act as a diffusion barrier between the CVD-W coating and the substrate. The prepared CuCrZr/PVD-Cu/CVD-W sample with active cooling has passed thermal fatigue tests by electron beam with an absorbed power of 2.2 MW/m2, 50 s on/50 s off, for 100 cycles. Another graphite/PVD-Si/CVD-W sample without active cooling underwent thermal fatigue testing with an absorbed power density of 4.62 MW/m2, 5 s on/25 s off, for 200 cycles, and no catastrophic failure was found.
Raman mapping of oral buccal mucosa: a spectral histopathology approach
NASA Astrophysics Data System (ADS)
Behl, Isha; Kukreja, Lekha; Deshmukh, Atul; Singh, S. P.; Mamgain, Hitesh; Hole, Arti R.; Krishna, C. Murali
2014-12-01
Oral cancer is one of the most common cancers worldwide. One-fifth of the world's oral cancer subjects are from India and other South Asian countries. The present Raman mapping study was carried out to understand biochemical variations in normal and malignant oral buccal mucosa. Data were acquired using WITec alpha 300R instrument from 10 normal and 10 tumors unstained tissue sections. Raman maps of normal sections could resolve the layers of epithelium, i.e. basal, intermediate, and superficial. Inflammatory, tumor, and stromal regions are distinctly depicted on Raman maps of tumor sections. Mean and difference spectra of basal and inflammatory cells suggest abundance of DNA and carotenoids features. Strong cytochrome bands are observed in intermediate layers of normal and stromal regions of tumor. Epithelium and stromal regions of normal cells are classified by principal component analysis. Classification among cellular components of normal and tumor sections is also observed. Thus, the findings of the study further support the applicability of Raman mapping for providing molecular level insights in normal and malignant conditions.
Raman microspectroscopic study of oral buccal mucosa
NASA Astrophysics Data System (ADS)
Behl, Isha; Mamgain, Hitesh; Deshmukh, Atul; Kukreja, Lekha; Hole, Arti R.; Krishna, C. Murali
2014-03-01
Oral cancer is the most common cancer among Indian males, with 5-year- survival-rates of less than 50%. Efficacy of Raman spectroscopic methods in non-invasive and objective diagnosis of oral cancers and confounding factors has already been demonstrated. The present Raman microspectroscopic study was undertaken for in-depth and site-specific analysis of normal and tumor tissues. 10 normal and 10 tumors unstained sections from 20 tissues were accrued. Raman data of 160 x 60 μm and 140 x 140 μm in normal and tumor sections, respectively, were acquired using WITec alpha 300R equipped with 532 nm laser, 50X objective and 600 gr/mm grating. Spectral data were corrected for CCDresponse, background. First-derivitized and vector-normalized data were then subjected to K-mean cluster analysis to generate Raman maps and correlated with their respective histopathology. In normal sections, stratification among epithelial layers i.e. basal, intermediate, superficial was observed. Tumor, stromal and inflammatory regions were identified in case of tumor section. Extracted spectra of the pathologically annotated regions were subjected to Principal component analysis. Findings suggest that all three layers of normal epithelium can be differentiated against tumor cells. In epithelium, basal and superficial layers can be separated while intermediate layer show misclassifications. In tumors, discrimination of inflammatory regions from tumor cells and tumor-stroma regions were observed. Finding of the study indicate Raman mapping can lead to molecular level insights of normal and pathological states.
Tribology and hydrophobicity of a biocompatible GPTMS/PFPE coating on Ti6Al4V surfaces.
Panjwani, Bharat; Sinha, Sujeet K
2012-11-01
Tribological properties of perfluoropolyether (PFPE) coated 3-glycidoxypropyltrimethoxy silane (GPTMS) SAMs (self-assembled monolayers) onto Ti6Al4V alloy substrate were studied using ball-on-disk experiments. GPTMS SAMs deposition onto a Ti6Al4V alloy surface was carried out using solution phase method. Ultra-thin layer of PFPE was dip-coated onto SAMs modified specimens. Tribological tests were carried out at 0.2 N normal load and rotational speed of 200 rpm using track radius of 2 mm. Wear track and counterface surface conditions were investigated using optical microscopy. PFPE modified specimens were baked at 150 °C for 1h to investigate the effect of thermal treatment on tribological properties. Surface characterization tests such as contact angle measurement, AFM morphology and X-ray photoelectron spectroscopy were carried out for differently modified specimens. PFPE overcoat meets the requirements of cytotoxicity test using the ISO 10993-5 elution method. PFPE top layer lowered the coefficient of friction and increased wear durability for different specimens (with and without GPTMS intermediate layer). PFPE overcoat onto GPTMS showed significant increase in the wear resistance compared with overcoat onto bare Ti6Al4V specimens. The observed improvement in the tribological properties can be attributed to the change in the interaction of PFPE molecules with the substrate surface due to the GPTMS intermediate layer. Copyright © 2012 Elsevier Ltd. All rights reserved.
Polymer/graphite oxide composites as high-performance materials for electric double layer capacitors
NASA Astrophysics Data System (ADS)
Tien, Chien-Pin; Teng, Hsisheng
A single graphene sheet represents a carbon material with the highest surface area available to accommodating molecules or ions for physical and chemical interactions. Here we demonstrate in an electric double layer capacitor the outstanding performance of graphite oxide for providing a platform for double layer formation. Graphite oxide is generally the intermediate compound for obtaining separated graphene sheets. Instead of reduction with hydrazine, we incorporate graphite oxide with a poly(ethylene oxide)-based polymer and anchor the graphene oxide sheets with poly(propylene oxide) diamines. This polymer/graphite oxide composite shows in a "dry" gel-electrolyte system a double layer capacitance as high as 130 F g -1. The polymer incorporation developed here can significantly diversify the application of graphene-based materials in energy storage devices.
Qi, Guangxia; Yue, Dongbei; Liu, Jianguo; Li, Rui; Shi, Xiaochong; He, Liang; Guo, Jingting; Miao, Haomei; Nie, Yongfeng
2013-10-15
Waste samples at different depths of a covered municipal solid waste (MSW) landfill in Beijing, China, were excavated and characterized to investigate the impact of intermediate soil cover on waste stabilization. A comparatively high amount of unstable organic matter with 83.3 g kg(-1) dry weight (dw) total organic carbon was detected in the 6-year-old MSW, where toxic inorganic elements containing As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn of 10.1, 0.98, 85.49, 259.7, 530.4, 30.5, 84.0, and 981.7 mg kg(-1) dw, respectively, largely accumulated because of the barrier effect of intermediate soil cover. This accumulation resulted in decreased microbial activities. The intermediate soil cover also caused significant reduction in moisture in MSW under the soil layer, which was as low as 25.9%, and led to inefficient biodegradation of 8- and 10-year-old MSW. Therefore, intermediate soil cover with low permeability seems to act as a barrier that divides a landfill into two landfill cells with different degradation processes by restraining water flow and hazardous matter. Copyright © 2013 Elsevier Ltd. All rights reserved.
Solar cells with low cost substrates and process of making same
Mitchell, Kim W.
1984-01-01
A solar cell having a substrate and an intermediate recrystallized film and a semiconductor material capable of absorbing light with the substrate being selected from one of a synthetic organic resin, graphite, glass and a crystalline material having a grain size less than about 1 micron.sup.2. The intermediate recrystallized film has a grain size in the range of from about 10 microns.sup.2 to about 10,000 microns.sup.2 and a lattice mismatch with the semiconductor material not greater than about 4%. The semiconductor material has a grain size not less than about 10 microns.sup.2. An anti-reflective layer and electrical contact means are provided. Also disclosed is a subcombination of substrate, intermediate recrystallized film and semiconductor material. Also, methods of formulating the solar cell and subcombination are disclosed.
Solar cells with low cost substrates, process of making same and article of manufacture
Mitchell, K.W.
A solar cell is disclosed having a substrate and an intermediate recrystallized film and a semiconductor material capable of absorbing light with the substrate being selected from one of a synthetic organic resin, graphite, glass and a crystalline material having a grain size less than about 1 micron/sup 2/. The intermediate recrystallized film has a grain size in the range of from about 10 microns/sup 2/ to about 10,000 microns/sup 2/ and a lattice mismatch with the semiconductor material not greater than about 4%. The semiconductor material has a grain size not less than about 10 microns/sup 2/. An anti-reflective layer and electrical contact means are provided. Also disclosed is a subcombination of substrate, intermediate recrystallized film and semiconductor material. Also, methods of formulating the solar cell and subcombination are disclosed.
Rough-to-smooth transition of an equilibrium neutral constant stress layer
NASA Technical Reports Server (NTRS)
Logan, E., Jr.; Fichtl, G. H.
1975-01-01
Purpose of research on rough-to-smooth transition of an equilibrium neutral constant stress layer is to develop a model for low-level atmospheric flow over terrains of abruptly changing roughness, such as those occurring near the windward end of a landing strip, and to use the model to derive functions which define the extent of the region affected by the roughness change and allow adequate prediction of wind and shear stress profiles at all points within the region. A model consisting of two bounding logarithmic layers and an intermediate velocity defect layer is assumed, and dimensionless velocity and stress distribution functions which meet all boundary and matching conditions are hypothesized. The functions are used in an asymptotic form of the equation of motion to derive a relation which governs the growth of the internal boundary layer. The growth relation is used to predict variation of surface shear stress.
NASA Technical Reports Server (NTRS)
D'Anterroches, Cecile; Yakupoglu, H. Nejat; Lin, T. L.; Fathauer, R. W.; Grunthaner, P. J.
1988-01-01
Co and Si have been codeposited on Si (111) substrates near room temperature in a stoichiometric 1:2 ratio in a molecular beam epitaxy system. Annealing of these deposits yields high-quality single-crystal CoSi2 layers. Transmission electron microscopy has been used to examine as-deposited layers and layers annealed at 300, 500, and 600 C. Single-crystal epitaxial grains of CoSi2 embedded in a matrix of amorphous Co/Si are observed in as-deposited samples, while the layer is predominantly single-crystal, inhomogeneously strained CoSi2 at 300 C. At 600 C, a homogeneously strained single-crystal layer with a high density of pinholes is observed. In contrast to other solid phase epitaxy techniques used to grow CoSi2 on Si (111), no intermediate silicide phases are observed prior to the formation of CoSi2.
A nanometric cushion for enhancing scratch and wear resistance of hard films
Gotlib-Vainshtein, Katya; Girshevitz, Olga; Barlam, David
2014-01-01
Summary Scratch resistance and friction are core properties which define the tribological characteristics of materials. Attempts to optimize these quantities at solid surfaces are the subject of intense technological interest. The capability to modulate these surface properties while preserving both the bulk properties of the materials and a well-defined, constant chemical composition of the surface is particularly attractive. We report herein the use of a soft, flexible underlayer to control the scratch resistance of oxide surfaces. Titania films of several nm thickness are coated onto substrates of silicon, kapton, polycarbonate, and polydimethylsiloxane (PDMS). The scratch resistance measured by scanning force microscopy is found to be substrate dependent, diminishing in the order PDMS, kapton/polycarbonate, Si/SiO2. Furthermore, when PDMS is applied as an intermediate layer between a harder substrate and titania, marked improvement in the scratch resistance is achieved. This is shown by quantitative wear tests for silicon or kapton, by coating these substrates with PDMS which is subsequently capped by a titania layer, resulting in enhanced scratch/wear resistance. The physical basis of this effect is explored by means of Finite Element Analysis, and we suggest a model for friction reduction based on the "cushioning effect” of a soft intermediate layer. PMID:25161836
Lomako, Joseph; Lomako, Wieslawa M; Carothers Carraway, Coralie A; Carraway, Kermit L
2010-04-01
MUC4 is a heterodimeric membrane mucin, composed of a mucin subunit ASGP-1 (MUC4alpha) and a transmembrane subunit ASGP-2 (MUC4beta), which has been implicated in the protection of epithelial cell surfaces. In the rat stratified corneal epithelium Muc4 is found predominantly in the most superficial cell layers. Since previous studies in other tissues have shown that Muc4 is regulated by TGF-beta via a proteosomal degradation mechanism, we investigated the regulation of corneal Muc4 in stratified cultures of corneal epithelial cells. Application of proteosome or processing inhibitors led to increases in levels of Muc4, particularly in the basal and intermediate levels of the stratified cultures. These changes were accompanied by increases in Muc4 ubiquitination, chaperone association and incorporation into intracellular aggresomes. In contrast, treatment with TGF-beta resulted in reduced levels of Muc4, which were reversed by proteosome inhibition. The results support a model in which Muc4 precursor is synthesized in all layers of the corneal epithelium, but Muc4 is degraded in basal and intermediate layers by a proteosomal mechanism at least partly dependent on TGF-beta inhibition of Muc4 processing. J. Cell. Physiol. 223: 209-214, 2010. (c) 2009 Wiley-Liss, Inc.
Anthropogenic CO2 in a dense water formation area of the Mediterranean Sea
NASA Astrophysics Data System (ADS)
Ingrosso, Gianmarco; Bensi, Manuel; Cardin, Vanessa; Giani, Michele
2017-05-01
There is growing evidence that the on-going ocean acidification of the Mediterranean Sea could be favoured by its active overturning circulation. The areas of dense water formation are, indeed, preferential sites for atmospheric carbon dioxide absorption and through them the ocean acidification process can quickly propagate into the deep layers. In this study we estimated the concentration of anthropogenic CO2 (Cant) in the dense water formation areas of the middle and southern Adriatic Sea. Using the composite tracer TrOCA (Tracer combining Oxygen, inorganic Carbon, and total Alkalinity) and carbonate chemistry data collected throughout March 2013, our results revealed that a massive amount of Cant has invaded all the identified water masses. High Cant concentration was detected at the bottom layer of the Pomo Pit (middle Adriatic, 96.8±9.7 μmol kg-1) and Southern Adriatic Pit (SAP, 85.2±9.4 μmol kg-1), associated respectively with the presence of North Adriatic Dense Water (NAdDW) and Adriatic Dense Water (AdDW). This anthropogenic contamination was clearly linked to the dense water formation events, which govern strong CO2 flux from the atmosphere to the sea and the sinking of dense, CO2-rich surface waters to the deep sea. However, a very high Cant level (94.5±12.5 μmol kg-1) was also estimated at the intermediate layer, as a consequence of a recent vertical mixing that determined the physical and biogeochemical modification of the water of Levantine origin (i.e. Modified Levantine Intermediate Water, MLIW) and favoured the atmospheric CO2 intrusion. The penetration of Cant in the Adriatic Sea determined a significant pH reduction since the pre-industrial era (- 0.139±0.019 pH units on average). This estimation was very similar to the global Mediterranean Sea acidification, but it was again more pronounced at the bottom of the Pomo Pit, within the layer occupied by NAdDW (- 0.157±0.018 pH units), and at the intermediate layer of the recently formed MLIW (- 0.143±0.020 pH units). Our results indicate that the Adriatic Sea could potentially be one of the Mediterranean regions most affected by the ocean acidification and also demonstrate its active role in sequestering and storing Cant.
NASA Astrophysics Data System (ADS)
Song, Yifei; Kujofsa, Tedi; Ayers, John E.
2018-07-01
In order to evaluate various buffer layers for metamorphic devices, threading dislocation densities have been calculated for uniform composition In x Ga1- x As device layers deposited on GaAs (001) substrates with an intermediate graded buffer layer using the L MD model, where L MD is the average length of misfit dislocations. On this basis, we compare the relative effectiveness of buffer layers with linear, exponential, and S-graded compositional profiles. In the case of a 2 μm thick buffer layer linear grading results in higher threading dislocation densities in the device layer compared to either exponential or S-grading. When exponential grading is used, lower threading dislocation densities are obtained with a smaller length constant. In the S-graded case, lower threading dislocation densities result when a smaller standard deviation parameter is used. As the buffer layer thickness is decreased from 2 μm to 0.1 μm all of the above effects are diminished, and the absolute threading dislocation densities increase.
NASA Technical Reports Server (NTRS)
Downes, Stephanie M.; Farneti, Riccardo; Uotila, Petteri; Griffies, Stephen M.; Marsland, Simon J.; Bailey, David; Behrens, Erik; Bentsen, Mats; Bi, Daohua; Biastoch, Arne;
2015-01-01
We characterise the representation of the Southern Ocean water mass structure and sea ice within a suite of 15 global ocean-ice models run with the Coordinated Ocean-ice Reference Experiment Phase II (CORE-II) protocol. The main focus is the representation of the present (1988-2007) mode and intermediate waters, thus framing an analysis of winter and summer mixed layer depths; temperature, salinity, and potential vorticity structure; and temporal variability of sea ice distributions. We also consider the interannual variability over the same 20 year period. Comparisons are made between models as well as to observation-based analyses where available. The CORE-II models exhibit several biases relative to Southern Ocean observations, including an underestimation of the model mean mixed layer depths of mode and intermediate water masses in March (associated with greater ocean surface heat gain), and an overestimation in September (associated with greater high latitude ocean heat loss and a more northward winter sea-ice extent). In addition, the models have cold and fresh/warm and salty water column biases centred near 50 deg S. Over the 1988-2007 period, the CORE-II models consistently simulate spatially variable trends in sea-ice concentration, surface freshwater fluxes, mixed layer depths, and 200-700 m ocean heat content. In particular, sea-ice coverage around most of the Antarctic continental shelf is reduced, leading to a cooling and freshening of the near surface waters. The shoaling of the mixed layer is associated with increased surface buoyancy gain, except in the Pacific where sea ice is also influential. The models are in disagreement, despite the common CORE-II atmospheric state, in their spatial pattern of the 20-year trends in the mixed layer depth and sea-ice.
Efficient Ga(As)Sb quantum dot emission in AlGaAs by GaAs intermediate layer
NASA Astrophysics Data System (ADS)
Loeber, Thomas Henning; Richter, Johannes; Strassner, Johannes; Heisel, Carina; Kimmle, Christina; Fouckhardt, Henning
2013-03-01
Ga(As)Sb quantum dots (QDs) are epitaxially grown in AlGaAs/GaAs in the Stranski-Krastanov mode. In the recent past we achieved Ga(As)Sb QDs in GaAs with an extremely high dot density of 9.8•1010 cm-2 by optimization of growth temperature, Sb/Ga flux pressure ratio, and coverage. Additionally, the QD emission wavelength could be chosen precisely with these growth parameters in the range between 876 and 1035 nm. Here we report a photoluminescence (PL) intensity improvement for the case with AlGaAs barriers. Again growth parameters and layer composition are varied. The aluminium content is varied between 0 and 90%. Reflectance anisotropy spectroscopy (RAS) is used as insitu growth control to determine growth rate, layer thickness, and AlGaAs composition. Ga(As)Sb QDs, directly grown in AlxGa1-xAs emit no PL signal, even with a very low x ≈ 0.1. With additional around 10 nm thin GaAs intermediate layers between the Ga(As)Sb QDs and the AlGaAs barriers PL signals are detected. Samples with 4 QD layers and AlxGa1-xAs/GaAs barriers in between are grown. The thickness and composition of the barriers are changed. Depending on these values PL intensity is more than 4 times as high as in the case with simple GaAs barriers. With these results efficient Ga(As)Sb QD lasers are realized, so far only with pure GaAs barriers. Our index-guided broad area lasers operate continuous-wave (cw) @ 90 K, emit optical powers of more than 2•50 mW and show a differential quantum efficiency of 54% with a threshold current density of 528 A/cm2.
V x In (2–x) S 3 Intermediate Band Absorbers Deposited by Atomic Layer Deposition
McCarthy, Robert F.; Weimer, Matthew S.; Haasch, Richard T.; ...
2016-03-21
Substitutional alloys of several thin film semiconductors have been proposed as intermediate band (IB) materials for use in next-generation photovoltaics, which aim to utilize a larger fraction of the solar spectrum without sacrificing significant photovoltage. Here, we demonstrate a novel approach to IB material growth, namely atomic layer deposition (ALD), to enable unique control over substitutional-dopant location and density. Two new ALD processes for vanadium sulfide incorporation are introduced, one of which incorporates a vanadium (III) amidinate previously untested for ALD. We synthesize the first thin film V xIn (2-x)S 3 intermediate band semiconductors, using this process, and further demonstratemore » that the V:In ratio, and therefore intraband gap density of states, can be finely tuned according to the ALD dosing schedule. Deposition on a crystalline In 2S 3 underlayer promotes the growth of a tetragonal β-In 2S 3-like phase V xIn (2-x)S 3, which exhibits a distinct sub-band gap absorption peak with onset near 1.1 eV in agreement with computational predictions. But, the V xIn (2-x)S 3 films lack the lower energy transition predicted for a partially filled IB, and photoelectrochemical devices reveal a photocurrent response only from illumination with energy sufficient to span the parent band-gap.« less
NASA Astrophysics Data System (ADS)
Wang, Jiang; Li, Yongfang; Wang, Zhaolu; Han, Jing; Huang, Nan; Liu, Hongjun
2018-01-01
Broadband wavelength conversion based on degenerate four-wave mixing is theoretically investigated in a hydrogenated amorphous silicon (a-Si:H) waveguide with silicon nitride inter-cladding layer (a-Si:HN). We have found that enhancement of the non-linear effect of a-Si:H waveguide nitride intermediate layer facilitates broadband wavelength conversion. Conversion bandwidth of 490 nm and conversion efficiency of 11.4 dB were achieved in a numerical simulation of a 4 mm-long a-Si:HN waveguide under 1.55 μm continuous wave pumping. This broadband continuous-wave wavelength converter has potential applications in photonic networks, a type of readily manufactured low-cost highly integrated optical circuits.
NASA Technical Reports Server (NTRS)
Boclair, J. W.; Braterman, P. S.
1999-01-01
Solutions containing di- and trivalent metal chlorides [M(II) = Mg2+, Zn2+, Co2+, Ni2+, Mn2+; M(III) = Al3+, Fe3+] were titrated with NaOH to yield hydrotalcite-like layered double hydroxides (LDH), [[M(II)]1-x[M(III)]x(OH)2][Cl]x yH2O, by way of M(III) hydroxide/hydrous oxide intermediates. Analysis of the resultant titration curves yields nominal solubility constants for the LDH. The corresponding LDH stabilities are in the order Mg < Mn < Co approximately Ni < Zn for M(II) and Al < Fe for M(III). The stability of LDH relative to the separate metal hydroxides/hydrous oxides is discussed.
NASA Astrophysics Data System (ADS)
Yu, Yishan
The influence of various fillers, nucleating agents and ethylene propylene diene terpolymer (EPDM) additive on crystalline modification (alpha-, beta- and smectic forms) and crystalline orientation of polypropylene in die extrudates, melt spun filaments, thick rods, blow molded bottles and injection molded parts of isotactic polypropylene (PP), its blends/compounds and dynamically vulcanized polypropylene thermoplastic elastomers (TPEs) were experimentally studied under a range of cooling and processing conditions. The phenomena of crystallization, polymorphism and orientation in processing of both thin and thick samples (filaments, rods, bottles and injection molded parts) were simulated through transport laws incorporating polymer crystallization kinetics. Continuous cooling transformation (CCT) curves for the various material systems investigated were developed under quiescent and uniaxial stress conditions. We applied experimental data on polymorphism of thin sections to predict crystalline structure variation in thick parts. The predictions were consistent with experiments. For filaments, the polypropylene crystalline orientation-spinline stress relationship is generally similar for the neat PP, blends/compounds and TPEs. However, the blends and TPEs have much lower birefringence apparently due to a lack of orientation in the rubber phase. It was shown that the polypropylene contribution to the birefringence for the neat PP and its blends is the same at the same spinline stress. For bottles, the inflation pressures used have little effect on orientation of either polypropylene crystals or disc-shaped talc filler. The talc discs are highly oriented parallel to the bottle surface. For the bottles without talc, the orientation of polypropylene crystallographic axes are low. The polypropylene crystallographic b-axes in the talc filled bottles are more highly oriented. For injection molded parts, it was found that a low orientation layer exists between the part surface and an intermediate highly oriented layer in the parts of neat PP and its blends/compounds. The thickness of this layer increases as the injection pressure decreases. This layer was not formed in the TPE parts. This would seem to be associated with the TPEs exhibiting a yield stress in shear flow and not exhibiting fountain flow in mold filling. For all parts studied, the orientation characteristics of polypropylene crystallographic axes in the highly oriented layer are similar from sample to sample. The strong orientation of the c-axis parallel to the machine direction and the b-axis perpendicular to the machine direction are observed in the highly oriented layer. The talc discs in both the highly oriented layer and the intermediate position are highly oriented parallel to the part face due to melt flow. At intermediate position in the talc-filled parts, the polypropylene crystallographic (040) planes prefer to align themselves parallel to the part surface but are not so well oriented when the talc is absent.
Energy transfer through a multi-layer liner for shaped charges
Skolnick, Saul; Goodman, Albert
1985-01-01
This invention relates to the determination of parameters for selecting materials for use as liners in shaped charges to transfer the greatest amount of energy to the explosive jet. Multi-layer liners constructed of metal in shaped charges for oil well perforators or other applications are selected in accordance with the invention to maximize the penetrating effect of the explosive jet by reference to four parameters: (1) Adjusting the explosive charge to liner mass ratio to achieve a balance between the amount of explosive used in a shaped charge and the areal density of the liner material; (2) Adjusting the ductility of each layer of a multi-layer liner to enhance the formation of a longer energy jet; (3) Buffering the intermediate layers of a multi-layer liner by varying the properties of each layer, e.g., composition, thickness, ductility, acoustic impedance and areal density, to protect the final inside layer of high density material from shattering upon impact of the explosive force and, instead, flow smoothly into a jet; and (4) Adjusting the impedance of the layers in a liner to enhance the transmission and reduce the reflection of explosive energy across the interface between layers.
Kong, Qingna; Yao, Jun; Qiu, Zhanhong; Shen, Dongsheng
2016-01-01
Municipal solid waste incinerator (MSWI) bottom ash is often used as the protection layer for the geomembrane and intermediate layer in the landfill. In this study, three sets of simulated landfills with different mass proportion of MSWI bottom ash layer to municipal solid waste (MSW) layer were operated. Cu and Zn concentrations in the leachates and MSW were monitored to investigate the effect of MSWI bottom ash layer on the Cu and Zn discharge from the landfill. The results showed that the Zn discharge was dependent on the mass proportion of MSWI bottom ash layer. The pH of landfill was not notably increased when the mass proportion of MSWI bottom ash layer to MSW layer was 1 : 9, resulting in the enhancement of the Zn discharge. However, Zn discharge was mitigated when the mass proportion was 2 : 8, as the pH of landfill was notably promoted. The discharge of Cu was not dependent on the mass proportion, due to the great affinity of Cu to organic matter. Moreover, Cu and Zn contents of the sub-MSW layer increased due to the MSWI bottom ash layer. Therefore, the MSWI bottom ash layer can increase the potential environmental threat of the landfill.
Deep and intermediate mediterranean water in the western Alboran Sea
NASA Astrophysics Data System (ADS)
Parrilla, Gregorio; Kinder, Thomas H.; Preller, Ruth H.
1986-01-01
Hydrographic and current meter data, obtained during June to October 1982, and numerical model experiments are used to study the distribution and flow of Mediterranean waters in the western Alboran Sea. The Intermediate Water is more pronounced in the northern three-fourths of the sea, but its distribution is patchy as manifested by variability of the temperature and salinity maxima at scales ≤10 km. Current meters in the lower Intermediate Water showed mean flow toward the Strait at 2 cm s -1. A reversal of this flow lasted about 2 weeks. A rough estimate of the mean westward Intermediate Water transport was 0.4 × 10 6 m 3 s -1, about one-third of the total outflow, so that the best estimates of the contributions of traditionally defined Intermediate Water and Deep Water account for only about one-half of the total outflow. The Deep Water was uplifted against the southern continental slope from Alboran Island (3°W) to the Strait. There was also a similar but much weaker banking against the Spanish slope, but a deep current record showed that the eastward recirculation implied by this banking is probably intermittent. Two-layer numerical model experiments simulated the Intermediate Water flow with a flat bottom and the Deep Water with realistic bottom topography. Both experiments replicated the major circulation features, and the Intermediate Water flow was concentrated in the north because of rotation and the Deep Water flow in the south because of topographic control.
Zhao, Jing; Wang, Ya Xing; Zhang, Qi; Wei, Wen Bin; Xu, Liang; Jonas, Jost B
2018-03-13
To study macular choroidal layer thickness, 3187 study participants from the population-based Beijing Eye Study underwent spectral-domain optical coherence tomography with enhanced depth imaging for thickness measurements of the macular small-vessel layer, including the choriocapillaris, medium-sized choroidal vessel layer (Sattler's layer) and large choroidal vessel layer (Haller's layer). In multivariate analysis, greater thickness of all three choroidal layers was associated (all P < 0.05) with higher prevalence of age-related macular degeneration (AMD) (except for geographic atrophy), while it was not significantly (all P > 0.05) associated with the prevalence of open-angle glaucoma or diabetic retinopathy. There was a tendency (0.07 > P > 0.02) toward thinner choroidal layers in chronic angle-closure glaucoma. The ratio of small-vessel layer thickness to total choroidal thickness increased (P < 0.001; multivariate analysis) with older age and longer axial length, while the ratios of Sattler's layer and Haller's layer thickness to total choroidal thickness decreased. A higher ratio of small-vessel layer thickness to total choroidal thickness was significantly associated with a lower prevalence of AMD (early type, intermediate type, late geographic type). Axial elongation-associated and aging-associated choroidal thinning affected Haller's and Sattler's layers more markedly than the small-vessel layer. Non-exudative and exudative AMD, except for geographic atrophy, was associated with slightly increased choroidal thickness.
Yang, Chun; Wang, Limin
2016-01-01
The histology and morphology characteristics of the tongue in Scincella tsinlingensis were studied by light and electronic microscopy. Under light microscopy, the tongue consists of tip, lingual body and radix in sequence. Numerous lingual papillae widely distribute on the surface of the dorsal and ventral flanks in the tongue, in addition to some regions of the tip. The papillae's surface is covered with the epithelial layer. The lamina propria and dense connective tissue are distinct existing under the epithelial layer. There are many lingual glands spread over the lamina propria. Tongue muscle is developed and composed of distinct intrinsic muscle, hyoglossus and genioglossus. By scanning electron microscopy, at higher magnification, the epithelial cells of the dorsal surface in the divaricate tongue tips show numerous microvilli, micro-ridges and micro-pores. The surface of dorsal side of the papillae in lingual body is covered with abundant of micro-ridges and taste bud lacuna. On the surface of the papillae in radix, micro-facets and micro-ridges are compactly distributed, as well as scattered mucilage-pores. The lingual epithelium is divided into four layers observed by the transmission electron microscope. Cells of basal layer are irregularly elliptical in shape, with sparse organelles in the cytoplasm. The deep intermediate layer is not always distinct. Small numbers of organelles are scattered into the cytoplasm. The cells of the superficial intermediate layer gradually flatten, as do their nuclei. The cytoplasm contains many keratohyalin granules. Cell membranes are formed processes around cells and joined by abundant desmosomes to the cell membranes of adjacent cells. The cells located on the extreme free-surface side of the keratinized layer have fallen off. The basal lamina is intercalated between the basal layer and the lamina propria. The lamina propria of lingual body contains lingual gland. A large part of the cytoplasm is occupied by mucus granules which located in the distal part of the cell. The connective tissue contains myelinated nerve fibers, vessel and muscle cells. Copyright © 2015 Elsevier Ltd. All rights reserved.
International Computer and Information Literacy Study: Assessment Framework
ERIC Educational Resources Information Center
Fraillon, Julian; Schulz, Wolfram; Ainley, John
2013-01-01
The purpose of the International Computer and Information Literacy Study 2013 (ICILS 2013) is to investigate, in a range of countries, the ways in which young people are developing "computer and information literacy" (CIL) to support their capacity to participate in the digital age. To achieve this aim, the study will assess student…
Independent Orbiter Assessment (IOA): Analysis of the auxiliary power unit
NASA Technical Reports Server (NTRS)
Barnes, J. E.
1986-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Auxiliary Power Unit (APU). The APUs are required to provide power to the Orbiter hydraulics systems during ascent and entry flight phases for aerosurface actuation, main engine gimballing, landing gear extension, and other vital functions. For analysis purposes, the APU system was broken down into ten functional subsystems. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode. A preponderance of 1/1 criticality items were related to failures that allowed the hydrazine fuel to escape into the Orbiter aft compartment, creating a severe fire hazard, and failures that caused loss of the gas generator injector cooling system.
NASA Technical Reports Server (NTRS)
Brown, K. L.; Bertsch, P. J.
1986-01-01
Results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Electrical Power Generation (EPG)/Fuel Cell Powerplant (FCP) hardware. The EPG/FCP hardware is required for performing functions of electrical power generation and product water distribution in the Orbiter. Specifically, the EPG/FCP hardware consists of the following divisions: (1) Power Section Assembly (PSA); (2) Reactant Control Subsystem (RCS); (3) Thermal Control Subsystem (TCS); and (4) Water Removal Subsystem (WRS). The IOA analysis process utilized available EPG/FCP hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.
Independent Orbiter Assessment (IOA): Analysis of the reaction control system, volume 1
NASA Technical Reports Server (NTRS)
Burkemper, V. J.; Haufler, W. A.; Odonnell, R. A.; Paul, D. J.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results for the Reaction Control System (RCS). The purpose of the RCS is to provide thrust in and about the X, Y, Z axes for External Tank (ET) separation; orbit insertion maneuvers; orbit translation maneuvers; on-orbit attitude control; rendezvous; proximity operations (payload deploy and capture); deorbit maneuvers; and abort attitude control. The RCS is situated in three independent modules, one forward in the orbiter nose and one in each OMS/RCS pod. Each RCS module consists of the following subsystems: Helium Pressurization Subsystem; Propellant Storage and Distribution Subsystem; Thruster Subsystem; and Electrical Power Distribution and Control Subsystem. Of the failure modes analyzed, 307 could potentially result in a loss of life and/or loss of vehicle.
Independent Orbiter Assessment (IOA): Analysis of the orbital maneuvering system
NASA Technical Reports Server (NTRS)
Prust, C. D.; Paul, D. J.; Burkemper, V. J.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The independent analysis results for the Orbital Maneuvering System (OMS) hardware are documented. The OMS provides the thrust to perform orbit insertion, orbit circularization, orbit transfer, rendezvous, and deorbit. The OMS is housed in two independent pods located one on each side of the tail and consists of the following subsystems: Helium Pressurization; Propellant Storage and Distribution; Orbital Maneuvering Engine; and Electrical Power Distribution and Control. The IOA analysis process utilized available OMS hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluted and analyzed for possible failure modes and effects. Criticality was asigned based upon the severity of the effect for each failure mode.
DOT National Transportation Integrated Search
2008-12-01
This study has extended the capability of the SW model in order to predict the response of laterally loaded large diameter shafts considering 1) the influence of shaft type on the lateral shaft response; 2) the nonlinear behavior of shaft material an...
Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.
2015-06-02
The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.
Reese, Jason A; Keenihan, James R; Gaston, Ryan S; Kauffmann, Keith L; Langmaid, Joseph A; Lopez, Leonardo; Maak, Kevin D; Mills, Michael E; Ramesh, Narayan; Teli, Samar R
2017-03-21
The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.
ERIC Educational Resources Information Center
Pennington, Martha C.
An analysis of classroom discourse proposes four frames, modeled as concentric circles. The inner most circle is the lesson frame, removed or sheltered from outside influences and most likely, in a language class, to maintain second-language usage. The next frame from the center is the lesson-support frame, an intermediate layer of classroom…
DOT National Transportation Integrated Search
2015-06-01
Base aggregate is one of the intermediate layers in a pavement system for both flexible and rigid surfaces. Characterization : of base aggregate is necessary for pavement thickness design. Many transportation agencies, including the Virginia Departme...
Gómez, L; Rodríguez-Amaro, R
2008-10-07
The overall electrochemistry of 7,7,8,8-tetracyanoquinodimethane thin films on glassy carbon electrodes in media containing Cs+ ions is explained in light of a layer-by-layer nucleation and growth model, and kinetic data for the processes involved are reported. Using in situ UV-vis spectroelectrochemistry allowed available mechanistic knowledge on such processes to be expanded and the presence of various intermediates in the redox reactions confirmed.
Adsorption of parahydrogen on graphene
NASA Astrophysics Data System (ADS)
Dusseault, Marisa; Boninsegni, Massimo
2018-05-01
We study the low-temperature properties of a single layer of parahydrogen adsorbed on graphene, by means of quantum Monte Carlo simulations. The computed phase diagram is very similar to that of helium on the same substrate, featuring commensurate solid phases with fillings 1/3 and 7/16, as well as domain-wall phases at intermediate coverages. At higher coverage the system transitions to an incommensurate, compressible phase. Evidence of promotion of molecules to the second layer is observed at a coverage ˜0.112 Å-2, significantly above existing theoretical estimates.
On the Nickel Hydroxide Electrode. I. On Nickel (II) Hydroxide Hydrate,
1980-10-27
1 - 4.60 A), and the hydrous form is halloysite , AI 2Si2 O5 (OH)4 .2H20 with d001 - 10.25 A (analogous to a-3Ni(OH)2 .2H20 with do01 - 8.07 A). On...heating of halloysite , the entire intermediate layer water is lost at about 1500 C, as for a nickel hydroxide, without the hydroxide layer separation...significantly reducing to meta- halloysite . 13 The conversion of the a form under the influence of alkali goes only in one direction. This monotropic
NASA Astrophysics Data System (ADS)
Baig, Mirza A.; Patel, Faheemuddin; Alhooshani, Khalid; Muraza, Oki; Wang, Evelyn N.; Laoui, Tahar
2015-12-01
LTA zeolite layer was successfully grown on a superhydrophilic mesoporous titania layer coated onto porous α-alumina substrate. Mesoporous titania layer was formed as an intermediate bridge in the pore size variation between the macroporous α-alumina support and micro-porous LTA zeolite layer. In-situ aging microwave heating synthesis method was utilized to deposit the LTA zeolite layer. Mesoporous titania layer was pre-treated with UV photons and this was observed to have played a major role in improving the surface hydrophilicity of the substrate leading to formation of increased number of Ti-OH groups on the surface. This increase in Ti-OH groups enhanced the interaction between the synthesis gel and the substrate leading to strong attachment of the amorphous gel on the substrate, thus enhancing coverage of the LTA zeolite layer to almost the entire surface of the 1-inch (25.4 mm) diameter membrane. LTA zeolite layer was developed via in-situ aged under microwave irradiation to study the effect of synthesis parameters such as in-situ aging time and synthesis time on the formation of the LTA zeolite layer. Optimized process parameters resulted in the formation of crack-free porous zeolite layer yielding a zeolite-titania-alumina multi-layer membrane with a gradient in porosity.
Laboratory simulation of infrared astrophysical features. Ph.D. Thesis; [emission spectra of comets
NASA Technical Reports Server (NTRS)
Rose, L. A.
1977-01-01
Intermediate resolution emission spectroscopy was used to study a group of 9 terrestrial silicates, 1 synthetic silicate, 6 meteorites and 2 lunar soils; comparisons were made with the intermediate resolution spectra of Comet Kohoutek in order to determine which materials best simulate the 10um astrophysical feature. Mixtures of silicates which would yield spectra matching the spectrum of the comet in the 10um region include: (1) A hydrous layer lattice silicate in combination with a high temperature condensate; (2) an amorphous magnesium silicate in combination with a high temperature condensate and (3) glassy olivine and glassy anorthite in approximately equal proportions.
Ponssa, María Laura; Barrionuevo, J Sebastián; Pucci Alcaide, Franco; Pucci Alcaide, Ana
2017-10-01
Leptodactylus is a genus of frogs known to live in diverse habitats and to show both aquatic and terrestrial breeding habits. We studied 21 species of Leptodactylus to explore whether skin structure specialization relates to habitats and habit variation. Morphometric analyses of the skin thickness revealed that phylogeny has a strong influence on variations in the thickness of the epidermis, stratum spongiosum, Eberth-Kastschenko layer, and stratum compactum, while habitat and habits display no significant correlation. The optimization of the phylogenetic hypothesis suggested that a pattern of intermediate values for skin layer thickness are plesiomorphic for this group. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 300:1895-1909, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Asryan, L. V., E-mail: asryan@vt.edu; Zubov, F. I.; Kryzhanovskaya, N. V.
2016-10-15
The power characteristics of quantum-well lasers with asymmetric barrier layers, which represent a novel type of injection laser, are calculated on the basis of an extended model taking into account asymmetry in the filling of electron and hole states. The electron–hole asymmetry is shown to have no significant effect on the characteristics of these lasers. Even in the presence of intermediate layers (located between the quantum well and each of the two asymmetric barrier layers), where parasitic electron–hole recombination does occur, the internal differential quantum efficiency of such a laser exhibits only a weak dependence on the pump current andmore » remains close to unity; therefore, the light–current characteristic remains linear up to high pumping levels.« less
Ramachandran, Dhanya; Egoavil, Ricardo; Crabbe, Amandine; Hauffman, Tom; Abakumov, Artem; Verbeeck, Johan; Vandendael, Isabelle; Terryn, Herman; Schryvers, Dominique
2016-11-01
The chemical composition, nanostructure and electronic structure of nanosized oxide scales naturally formed on the surface of AISI 316L stainless steel microfibres used for strengthening of composite materials have been characterised using a combination of scanning and transmission electron microscopy with energy-dispersive X-ray, electron energy loss and Auger spectroscopy. The analysis reveals the presence of three sublayers within the total surface oxide scale of 5.0-6.7 nm thick: an outer oxide layer rich in a mixture of FeO.Fe 2 O 3 , an intermediate layer rich in Cr 2 O 3 with a mixture of FeO.Fe 2 O 3 and an inner oxide layer rich in nickel. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.
NASA Astrophysics Data System (ADS)
Manakhov, Anton; Makhneva, Ekaterina; Skládal, Petr; Nečas, David; Čechal, Jan; Kalina, Lukáš; Eliáš, Marek; Zajíčková, Lenka
2016-01-01
The performance of immunosensing devices crucially depends on the methodology of antibody or antigen immobilization on the sensor surface. Hence, the stable intermediate layers capable of specific and reproducible binding of antibodies are required. Herein, we introduce the amine rich (NHx concentration of 6 at.%) layers prepared by pulsed plasma polymerization of cyclopropylamine (CPA) for functionalization of the quartz crystal microbalance (QCM) surface by the antibody specific to human serum albumin. In these layers the amine groups serve as anchor for the antibody binding. The sensitivity of QCM sensors prepared in this way surpasses the one for the previously reported sensors functionalized by the thiol-based self-assembled monolayers by the factor of 2. Our results thus show that CPA plasma polymers have a significant potential for further development of the active layers for biosensing applications.
NASA Astrophysics Data System (ADS)
Kumar, Rajeev; Kushwaha, Angad S.; Srivastava, Monika; Mishra, H.; Srivastava, S. K.
2018-03-01
In the present communication, a highly sensitive surface plasmon resonance (SPR) biosensor with Kretschmann configuration having alternate layers, prism/zinc oxide/silver/gold/graphene/biomolecules (ss-DNA) is presented. The optimization of the proposed configuration has been accomplished by keeping the constant thickness of zinc oxide (32 nm), silver (32 nm), graphene (0.34 nm) layer and biomolecules (100 nm) for different values of gold layer thickness (1, 3 and 5 nm). The sensitivity of the proposed SPR biosensor has been demonstrated for a number of design parameters such as gold layer thickness, number of graphene layer, refractive index of biomolecules and the thickness of biomolecules layer. SPR biosensor with optimized geometry has greater sensitivity (66 deg/RIU) than the conventional (52 deg/RIU) as well as other graphene-based (53.2 deg/RIU) SPR biosensor. The effect of zinc oxide layer thickness on the sensitivity of SPR biosensor has also been analysed. From the analysis, it is found that the sensitivity increases significantly by increasing the thickness of zinc oxide layer. It means zinc oxide intermediate layer plays an important role to improve the sensitivity of the biosensor. The sensitivity of SPR biosensor also increases by increasing the number of graphene layer (upto nine layer).
Potentiometric surface of the intermediate aquifer system, west- central Florida, May 1987
Lewelling, B.R.
1988-01-01
The intermediate aquifer system within the Southwest Florida Water Management District underlies a 5,000 sq mi area of De Soto, Sarasota, Hardee, Manatee, and parts of Charlotte, Hillsborough, Highlands, and Polk Counties. The intermediate aquifer system occurs between the overlying surficial aquifer system and the underlying Floridan aquifer system, and consists of layers of sand, shell, clay, marl, limestone, and dolom of the Tamiami, Hawthorn, and Tampa Formations of late Tertiary age. The intermediate aquifer system contains one or more water-bearing units separated by discontinuous confining units. This aquifer system is the principal source of potable water in the southwestern part of the study area and is widely used as a source of water in other parts where wells are open to the intermediate aquifer system or to both the intermediate and Floridan aquifer systems. Yields of individual wells open to the intermediate aquifer system range from a few gallons to several hundred gallons per minute. The volume of water withdrawn from the intermediate aquifer system is considerably less than that withdrawn from the Floridan aquifer system in the study area. The surface was mapped by determining the altitude of water levels in a network of wells and is represented on maps by contours that connect points of equal altitude. The compos potentiometric surface of all water-bearing units within the intermediate aquifer system is shown. In areas where multiple aquifers exist, wells open to all aquifers were selected for water level measurements whenever possible. In the southwestern and lower coastal region of the study area, two aquifers and confining units are described for the intermediate aquifer system: the Tamiami-upper Hawthorn aquifer and the underlying lower Hawthorn-upper Tampa aquifer. The potentiometric surface of the Tamiami-upper Hawthorn aquifer is also shown. Water levels are from wells drilled and open exclusively to that aquifer. The exact boundary for the Tamiami-upper Hawthorn aquifer is undetermined because of limd geohydrologic data available from wells. (Lantz-PTT)
George, J P; Smet, P F; Botterman, J; Bliznuk, V; Woestenborghs, W; Van Thourhout, D; Neyts, K; Beeckman, J
2015-06-24
The electro-optical properties of lead zirconate titanate (PZT) thin films depend strongly on the quality and crystallographic orientation of the thin films. We demonstrate a novel method to grow highly textured PZT thin films on silicon using the chemical solution deposition (CSD) process. We report the use of ultrathin (5-15 nm) lanthanide (La, Pr, Nd, Sm) based intermediate layers for obtaining preferentially (100) oriented PZT thin films. X-ray diffraction measurements indicate preferentially oriented intermediate Ln2O2CO3 layers providing an excellent lattice match with the PZT thin films grown on top. The XRD and scanning electron microscopy measurements reveal that the annealed layers are dense, uniform, crack-free and highly oriented (>99.8%) without apparent defects or secondary phases. The EDX and HRTEM characterization confirm that the template layers act as an efficient diffusion barrier and form a sharp interface between the substrate and the PZT. The electrical measurements indicate a dielectric constant of ∼650, low dielectric loss of ∼0.02, coercive field of 70 kV/cm, remnant polarization of 25 μC/cm(2), and large breakdown electric field of 1000 kV/cm. Finally, the effective electro-optic coefficients of the films are estimated with a spectroscopic ellipsometer measurement, considering the electric field induced variations in the phase reflectance ratio. The electro-optic measurements reveal excellent linear effective pockels coefficients of 110 to 240 pm/V, which makes the CSD deposited PZT thin film an ideal candidate for Si-based active integrated nanophotonic devices.
Paracentral acute middle maculopathy in nonischemic central retinal vein occlusion.
Rahimy, Ehsan; Sarraf, David; Dollin, Michael L; Pitcher, John D; Ho, Allen C
2014-08-01
To better characterize a novel spectral-domain optical coherence tomography (OCT) presentation, termed paracentral acute middle maculopathy, to describe this finding in patients with nonischemic central retinal vein occlusion (CRVO), and to support a proposed pathogenesis of intermediate and deep retinal capillary ischemia. Retrospective observational case series. Clinical histories, high-resolution digital color imaging, red-free photography, fluorescein angiography, near-infrared reflectance, and spectral-domain OCT images of 484 patients with acute CRVO from 2 centers were evaluated for the presence of coexisting paracentral acute middle maculopathy. Of 484 patients diagnosed with CRVO, 25 (5.2%) demonstrated evidence of concurrent paracentral acute middle maculopathy. Patients averaged 51 years of age and presented with complaints of paracentral scotomas. All patients demonstrated hyper-reflective plaquelike lesions at the level of the inner nuclear layer by spectral-domain OCT and showed corresponding dark-gray lesions on near-infrared reflectance and perivenular deep retinal whitening on color fundus photography. There was no fluorescein angiographic correlate to these lesions. On follow-up spectral-domain OCT imaging, the lesions had resolved into areas of inner nuclear layer atrophy with persistence of scotomas. Paracentral acute middle maculopathy refers to characteristic hyper-reflective spectral-domain OCT lesions involving the middle layers of the retina at the level of the inner nuclear layer that may develop in response to ischemia of the intermediate and deep capillary plexuses. This series is the largest to describe this spectral-domain OCT finding to date, and it is the first to associate it with nonischemic CRVO. Copyright © 2014 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Wu, Qinke; Jung, Seong Jun; Jang, Sung Kyu; Lee, Joohyun; Jeon, Insu; Suh, Hwansoo; Kim, Yong Ho; Lee, Young Hee; Lee, Sungjoo; Song, Young Jae
2015-06-01
We report the selective growth of large-area bilayered graphene film and multilayered graphene film on copper. This growth was achieved by introducing a reciprocal chemical vapor deposition (CVD) process that took advantage of an intermediate h-BN layer as a sacrificial template for graphene growth. A thin h-BN film, initially grown on the copper substrate using CVD methods, was locally etched away during the subsequent graphene growth under residual H2 and CH4 gas flows. Etching of the h-BN layer formed a channel that permitted the growth of additional graphene adlayers below the existing graphene layer. Bilayered graphene typically covers an entire Cu foil with domain sizes of 10-50 μm, whereas multilayered graphene can be epitaxially grown to form islands a few hundreds of microns in size. This new mechanism, in which graphene growth proceeded simultaneously with h-BN etching, suggests a potential approach to control graphene layers for engineering the band structures of large-area graphene for electronic device applications.We report the selective growth of large-area bilayered graphene film and multilayered graphene film on copper. This growth was achieved by introducing a reciprocal chemical vapor deposition (CVD) process that took advantage of an intermediate h-BN layer as a sacrificial template for graphene growth. A thin h-BN film, initially grown on the copper substrate using CVD methods, was locally etched away during the subsequent graphene growth under residual H2 and CH4 gas flows. Etching of the h-BN layer formed a channel that permitted the growth of additional graphene adlayers below the existing graphene layer. Bilayered graphene typically covers an entire Cu foil with domain sizes of 10-50 μm, whereas multilayered graphene can be epitaxially grown to form islands a few hundreds of microns in size. This new mechanism, in which graphene growth proceeded simultaneously with h-BN etching, suggests a potential approach to control graphene layers for engineering the band structures of large-area graphene for electronic device applications. Electronic supplementary information (ESI) available: The growth conditions, statistical studies of OM images and high-resolution STM/TEM measurements for multi-/bi-layered graphene are discussed in detail. See DOI: 10.1039/c5nr02716k
Powerful Letter Writing: Students Discover the Power of the Pen(cil).
ERIC Educational Resources Information Center
Neuhauser, Sandra P.
Students can better experience the impact of written words by the response of a real audience. This paper describes a letter-writing activity for sixth graders in which the students first identified and discussed real-life happenings which had caused disappointments with companies that had produced faulty items. They then obtained all the…
Bibliography of In-House and Contract Reports. Supplement 9.
1981-02-01
11;il CasCil roads andl ril roads would significantlN rcduLcc tlic ~anIual labor IMnOls d III V, i 1111111 d il.1 . graphic data bascs. ile effort...GUIDE FOR CLIMA TE (Rpt. No. 5 in the ETL Series on Guides for Army Terrain Analysts) September 1980 Keywords: Climatic Analysis, Factor Mapping
ERIC Educational Resources Information Center
Gerick, Julia; Eickelmann, Birgit; Bos, Wilfried
2017-01-01
The "International Computer and Information Literacy Study" (ICILS 2013) provides, for the first time, information about students' computer and information literacy (CIL), as well as its acquisition, based on a computer-based test for students and background questionnaires. Among the 21 education systems that participated in ICILS 2013,…
Calculations of Shipboard Heat Exchangers,
1980-04-18
tubp plate with the Fercil cf szraight lines tutes (cn %’blepW68) d= I 1.&衊 == 0,563. Tha safety factcr c. panal is taken n=4. Allowable stress in...specific gravity/weight with 150C, kg/m 3 . ENDFOC[NOTE. (3). Petroleum residue F. (4). Cil. (5). turbine. (6). motor. (7). solar . t’ DOC 10
Textual Concept Critical Analysis: Toward a Research Approach for Language Studies
ERIC Educational Resources Information Center
Osborn, Terry A.; Reagan, Timothy G.; Freiberg, Jo Ann
2011-01-01
When the International Society for Language Studies (ISLS) was founded in 2002 and the journal that is now "Critical Inquiry in Language Studies (CILS)" was in the planning stages, we recognized a need for an interdisciplinary, or perhaps even transdisciplinary (see Kaufman, Moss, & Osborn, 2003), venue for the publication of research on language…
Electron doped layered nickelates: Spanning the phase diagram of the cuprates
DOE Office of Scientific and Technical Information (OSTI.GOV)
Botana, Antia S.; Pardo, Victor; Norman, Michael R.
2017-07-01
Pr4Ni3O8 is an overdoped analog of hole-doped layered cuprates. Here we show via ab initio calculations that Ce-doped Pr4Ni3O8 (Pr3CeNi3O8) has the same electronic structure as the antiferromagnetic insulating phase of parent cuprates.We find that substantial Ce doping should be thermodynamically stable and that other 4+ cations would yield a similar antiferromagnetic insulating state, arguing this configuration is robust for layered nickelates of low-enough valence. The analogies with cuprates at different d fillings suggest that intermediate Ce-doping concentrations near 1/8 should be an appropriate place to search for superconductivity in these low-valence Ni oxides.
NASA Astrophysics Data System (ADS)
Wagle, Sanat; Decharat, Adit; Habib, Anowarul; Ahluwalia, Balpreet S.; Melandsø, Frank
2016-07-01
High frequency crossed-electrode transducers have been investigated, both as single and dual layer transducers. Prototypes of these transducers were developed for 4 crossed lines (yielding 16 square elements) on a polymer substrate, using a layer-by-layer deposition method for poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] with intermediate sputtered electrodes. The transducer was characterized using various methods [LCR analyzer, a pulse-echo experimental setup, and a numerical Finite element method (FEM) model] and evaluated in terms of uniformity of bandwidth and acoustical energy output. All 16 transducer elements produced broad-banded ultrasonic spectra with small variation in central frequency and -6 dB bandwidth. The frequency responses obtained experimentally were verified using a numerical model.
Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.
2015-09-01
The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device (10) with a multilayered photovoltaic cell assembly (100) and a body portion (200) joined at an interface region (410) and including an intermediate layer (500), at least one interconnecting structural member (1500), relieving feature (2500), unique component geometry, or any combination thereof.
Pretreatment of lubricated surfaces with sputtered cadmium oxide
NASA Technical Reports Server (NTRS)
Fusaro, Robert L. (Inventor)
1991-01-01
Cadmium oxide is used with a dry solid lubricant on a surface to improve wear resistance. The surface topography is first altered by photochemical etching to a predetermined pattern. The cadmium oxide is then sputtered onto the altered surface to form an intermediate layer to more tightly hold the dry lubricant, such as graphite.
NASA Astrophysics Data System (ADS)
Jeloaica, L.; Estève, A.; Djafari Rouhani, M.; Estève, D.
2003-07-01
The initial stage of atomic layer deposition of HfO2, ZrO2, and Al2O3 high-k films, i.e., the decomposition of HfCl4, ZrCl4, and Al(CH3)3 precursor molecules on an OH-terminated SiO2 surface, is investigated within density functional theory. The energy barriers are determined using artificial activation of vibrational normal modes. For all precursors, reaction proceeds through the formation of intermediate complexes that have equivalent formation energies (˜-0.45 eV), and results in HCl and CH4 formation with activation energies of 0.88, 0.91, and 1.04 eV for Hf, Zr, and Al based precursors, respectively. The reaction product of Al(CH3)3 decomposition is found to be more stable (by -1.45 eV) than the chemisorbed intermediate complex compared to the endothermic decomposition of HfCl4 and ZrCl4 chemisorbed precursors (0.26 and 0.29 eV, respectively).
NASA Astrophysics Data System (ADS)
Chen, Shumin; Gao, Ming; Wan, Yazhou; Du, Huiwei; Li, Yong; Ma, Zhongquan
2016-12-01
A silicon based ternary compound was supposed to be solid synthesized with In, Si and O elements by magnetron sputtering of indium tin oxide target (ITO) onto crystal silicon substrate at 250 °C. To make clear the configuration of the intermediate region, a potential method to obtain the chemical bonding of Si with other existing elements was exploited by X-ray photoelectron spectroscopy (XPS) instrument combined with other assisted techniques. The phase composition and solid structure of the interfacial region between ITO and Si substrate were investigated by X-ray diffraction (XRD) and high resolution cross sectional transmission electron microscope (HR-TEM). A photovoltaic device with structure of Al/Ag/ITO/SiOx/p-Si/Al was assembled by depositing ITO films onto the p-Si substrate by using magnetron sputtering. The new matter has been assumed to be a buffer layer for semiconductor-insulator-semiconductor (SIS) photovoltaic device and plays critical role for the promotion of optoelectronic conversion performance from the view point of device physics.
Zhang, Jian; Zhang, Qiaoxia; Wang, Lianhui; Li, Xing’ao; Huang, Wei
2016-01-01
A model of interface induction for interlayer growing is proposed for bandgap engineering insights into photocatalysis. In the interface of CdS/ZnS core/shell nanorods, a lamellar solid solution intermediate with uniform thickness and high crystallinity was formed under interface induction process. Merged the novel charge carrier transfer layer, the photocurrent of the core/shell/shell nanorod (css-NR) array was significantly improved to 14.0 mA cm−2 at 0.0 V vs. SCE, nearly 8 times higher than that of the perfect CdS counterpart and incident photon to electron conversion efficiency (IPCE) values above 50% under AM 1.5G irradiation. In addition, this array photoelectrode showed excellent photocatalytic stability over 6000 s. These results suggest that the CdS/Zn1−xCdxS/ZnS css-NR array photoelectrode provides a scalable charge carrier transfer channel, as well as durability, and therefore is promising to be a large-area nanostructured CdS-based photoanodes in photoelectrochemical (PEC) water splitting system. PMID:27250648
Kong, Qingna; Qiu, Zhanhong; Shen, Dongsheng
2016-01-01
Municipal solid waste incinerator (MSWI) bottom ash is often used as the protection layer for the geomembrane and intermediate layer in the landfill. In this study, three sets of simulated landfills with different mass proportion of MSWI bottom ash layer to municipal solid waste (MSW) layer were operated. Cu and Zn concentrations in the leachates and MSW were monitored to investigate the effect of MSWI bottom ash layer on the Cu and Zn discharge from the landfill. The results showed that the Zn discharge was dependent on the mass proportion of MSWI bottom ash layer. The pH of landfill was not notably increased when the mass proportion of MSWI bottom ash layer to MSW layer was 1 : 9, resulting in the enhancement of the Zn discharge. However, Zn discharge was mitigated when the mass proportion was 2 : 8, as the pH of landfill was notably promoted. The discharge of Cu was not dependent on the mass proportion, due to the great affinity of Cu to organic matter. Moreover, Cu and Zn contents of the sub-MSW layer increased due to the MSWI bottom ash layer. Therefore, the MSWI bottom ash layer can increase the potential environmental threat of the landfill. PMID:28044139
Structure and Microhardness of Cu-Ta Joints Produced by Explosive Welding
Maliutina, Iu. N.; Mali, V. I.; Bataev, I. A.; Bataev, A. A.; Esikov, M. A.; Smirnov, A. I.; Skorokhod, K. A.
2013-01-01
The structure and microhardness of Cu-Ta joints produced by explosive welding were studied. It was found that, during explosive welding, an intermediate layer 20⋯40 μm thick with a finely dispersed heterophase structure, formed between the welded copper and tantalum plates. The structure of the layer was studied by scanning and transmission electron microscopy. Microvolumes with tantalum particles distributed in a copper matrix and microvolumes of copper particles in a tantalum matrix were detected. The tantalum particles in copper have a size of 5⋯500 nm, with a predominance of 5⋯50 nm particles. A mechanism for the formation of the finely dispersed heterophase structure in explosive welding is proposed. The microhardness of interlayers with the heterophase structure reaches 280 HV, which far exceeds the microhardness of copper (~130 HV) and tantalum (~160 HV). Many twins of deformation origin were found in the structure of the copper plate. The effect of heating temperature in the range from 100 to 900°C on the microhardness of copper, tantalum, and the Cu-Ta welded joint was studied. Upon heating to 900°C, the microhardness of the intermediate layer decreases from 280 to 150 HV. The reduction in the strength properties of the weld material is mainly due to structural transformations in copper. PMID:24453818
Design of epitaxial CdTe solar cells on InSb substrates
Song, Tao; Kanevce, Ana; Sites, James R.
2015-11-01
Epitaxial CdTe has been shown by others to have a radiative recombination rate approaching unity, high carrier concentration, and low defect density. It has, therefore, become an attractive candidate for high-efficiency solar cells, perhaps becoming competitive with GaAs. The choice of substrate is a key design feature for epitaxial CdTe solar cells, and several possibilities (CdTe, Si, GaAs, and InSb) have been investigated by others. All have challenges, and these have generally been addressed through the addition of intermediate layers between the substrate and CdTe absorber. InSb is an attractive substrate choice for CdTe devices, because it has a closemore » lattice match with CdTe, it has low resistivity, and it is easy to contact. However, the valence-band alignment between InSb and p-type CdTe, which can both impede hole current and enhance forward electron current, is not favorable. Three strategies to address the band-offset problem are investigated by numerical simulation: heavy doping of the back part of the CdTe layer, incorporation of an intermediate CdMgTe or CdZnTe layer, and the formation of an InSb tunnel junction. Lastly, wach of these strategies is predicted to be helpful for higher cell performance, but a combination of the first two should be most effective.« less
Churkin, M.; McKee, E.H.
1974-01-01
The seismic profile of the crust of the northern part of the Basin and Range province by its thinness and layering is intermediate between typical continental and oceanic crust and resembles that of marginal ocean basins, especially those with thick sedimentary fill. The geologic history of the Great Basin indicates that it was the site of a succession of marginal ocean basins opening and closing behind volcanic arcs during much of Paleozoic time. A long process of sedimentation and deformation followed throughout the Mesozoic modifying, but possibly not completely transforming the originally oceanic crust to continental crust. In the Cenozoic, after at least 40 m.y. of quiescence and stable conditions, substantial crustal and upper-mantle changes are recorded by elevation of the entire region in isostatic equilibrium, crustal extension resulting in Basin and Range faulting, extensive volcanism, high heat flow and a low-velocity mantle. These phenomena, apparently the result of plate tectonics, are superimposed on the inherited subcontinental crust that developed from an oceanic origin in Paleozoic time and possibly retained some of its thin and layered characteristics. The present anomalous crust in the Great Basin represents an accretion of oceanic geosynclinal material to a Precambrian continental nucleus apparently as an intermediate step in the process of conversion of oceanic crust into a stable continental landmass or craton. ?? 1974.
NASA Astrophysics Data System (ADS)
Song, T.
2010-12-01
Subducting slab undergoes a series of dehydration reactions on their ways into the mantle and these processes are responsible for transporting water, recycling volatiles and chemical elements in arc magmas. It is generally accepted that the SOC is hydrated. However, it is not clear if subducting oceanic mantle (SOM) is hydrated and how deep the hydration is. Seismic refraction studies found that normal-fault type faulting can extend 12-20 km deep into the interior of the slab off Nicaragua, suggesting deep hydration of the SOM. Seismic refraction studies also found that the uppermost SOM is seismically slow and is partially serpentinized. The fluids released from dehydration inside the SOM can reduce the normal stress locally and facilitate the occurrences of intra-slab events through dehydration embrittlement and hydraulic fracture. It has been suggested that the dehydration of antigorite at about 600C is particularly important in facilitating the lower plane of the double seismic zone. To link the dehydration process to the occurrences of intra-slab events, it is critical to clarify where these events are located, either located at the dehydration boundary or in the neighborhood rocks. However, if the SOM is anhydrous, other mechanism, such as shear instabilities, has to be invoked to explain the occurrences of intermediate-depth intraslab earthquakes. Here I discuss locations of intermediate-depth intraslab earthquakes in Central Mexico subduction zone, where young Cocos plate subducts beneath North America plate. Recent studies involving local converted wave modeling and receiver function analysis indicate the presence of an ultra-slow velocity layer (USL) of about 3 km thick, likely an over-pressured upper oceanic crust. Most events display anomalously large converted SP waves that are 2-2.5 secs after direct P waves and finite difference modeling converge the location of these events about 9 km below the lower boundary USL. With a lower oceanic crust of about 3-5 km estimated from receiver function, these intermediate-depth earthquakes are about 6 km inside the SOM. There is no clear evidence yet indicating the presence of a partially serpentinized layer in such a young plate (10-15 Ma). Further waveform modeling is undertaken to explore the presence of such a partially serpentinized layer.
Air-coupled piezoelectric transducers with active polypropylene foam matching layers.
Gómez Alvarez-Arenas, Tomás E
2013-05-10
This work presents the design, construction and characterization of air-coupled piezoelectric transducers using 1-3 connectivity piezocomposite disks with a stack of matching layers being the outer one an active quarter wavelength layer made of polypropylene foam ferroelectret film. This kind of material has shown a stable piezoelectric response together with a very low acoustic impedance (<0.1 MRayl). These features make them a suitable candidate for the dual use or function proposed here: impedance matching layer and active material for air-coupled transduction. The transducer centre frequency is determined by the l/4 resonance of the polypropylene foam ferroelectret film (0.35 MHz), then, the rest of the transducer components (piezocomposite disk and passive intermediate matching layers) are all tuned to this frequency. The transducer has been tested in several working modes including pulse-echo and pitch-catch as well as wide and narrow band excitation. The performance of the proposed novel transducer is compared with that of a conventional air-coupled transducers operating in a similar frequency range.
What's on the Surface? Physics and Chemistry of Delta-Doped Surfaces
NASA Technical Reports Server (NTRS)
Hoenk, Michael
2011-01-01
Outline of presentation: 1. Detector surfaces and the problem of stability 2. Delta-doped detectors 3. Physics of Delta-doped Silicon 4. Chemistry of the Si-SiO2 Interface 5. Physics and Chemistry of Delta-doped Surfaces a. Compensation b. Inversion c. Quantum exclusion. Conclusions: 1. Quantum confinement of electrons and holes dominates the behavior of delta-doped surfaces. 2. Stability of delta-doped detectors: Delta-layer creates an approx 1 eV tunnel barrier between bulk and surface. 3. At high surface charge densities, Tamm-Shockley states form at the surface. 4. Surface passivation by quantum exclusion: Near-surface delta-layer suppresses T-S trapping of minority carriers. 5. The Si-SiO2 interface compensates the surface 6. For delta-layers at intermediate depth, surface inversion layer forms 7. Density of Si-SiO2 interface charge can be extremely high (>10(exp 14)/sq cm)
Some aspects of metallic ion chemistry and dynamics in the mesosphere and thermosphere
NASA Technical Reports Server (NTRS)
Mathews, J. D.
1987-01-01
The relationship between the formation of sporadic layers of metallic ion and the dumping of these ions into the upper mesosphere is discussed in terms of the tidal wind, classical (i.e., windshear) and other more complex, perhaps highly nonlinear layer formation mechanisms, and a possible circulation mechanism for these ions. Optical, incoherent scatter radar, rocket, and satellite derived evidence for various layer formation mechanisms and for the metallic ion circulation system is reviewed. The results of simple one dimensional numerical model calculations of sporadic E and intermediate layer formation are presented along with suggestions for more advanced models of intense or blanketing sporadic E. The flux of metallic ions dumped by the tidal wind system into the mesosphere is estimated and compared with estimates of total particle flux of meteoric origin. Possible effects of the metallic ion flux and of meteoric dust on D region ion chemistry are discussed.
Monolayer-Mediated Growth of Organic Semiconductor Films with Improved Device Performance.
Huang, Lizhen; Hu, Xiaorong; Chi, Lifeng
2015-09-15
Increased interest in wearable and smart electronics is driving numerous research works on organic electronics. The control of film growth and patterning is of great importance when targeting high-performance organic semiconductor devices. In this Feature Article, we summarize our recent work focusing on the growth, crystallization, and device operation of organic semiconductors intermediated by ultrathin organic films (in most cases, only a monolayer). The site-selective growth, modified crystallization and morphology, and improved device performance of organic semiconductor films are demonstrated with the help of the inducing layers, including patterned and uniform Langmuir-Blodgett monolayers, crystalline ultrathin organic films, and self-assembled polymer brush films. The introduction of the inducing layers could dramatically change the diffusion of the organic semiconductors on the surface and the interactions between the active layer with the inducing layer, leading to improved aggregation/crystallization behavior and device performance.
NASA Astrophysics Data System (ADS)
Zhamaletdinov, A. A.; Velikhov, E. P.; Shevtsov, A. N.; Kolobov, V. V.; Kolesnikov, V. E.; Skorokhodov, A. A.; Korotkova, T. G.; Ivonin, V. V.; Ryazantsev, P. A.; Birulya, M. A.
2017-06-01
This paper addresses the Kovdor-2015 Experiment involving frequency electromagnetic soundings of the Archaean basement of the Earth's crust in the southwestern part of the Kola Peninsula. Eleven soundings were carried out using two transmitting arrangements, 85 km apart. Each arrangement consisted of two mutually orthogonal grounded electric dipoles of 1.5 km long. The distances between the source and the receiver were 25 and 50 km. Interpretation of the results took into account the influence of displacement currents and static distortions. It is found that there is an intermediate conductive layer of the dilatancy-diffusion nature (DD layer) with a longitudinal conductivity of about one siemens at depths ranging from 1.5-2 to 5-7 km. The results are interpreted in the terms of geodynamics.
NASA Technical Reports Server (NTRS)
Miladinovich, Daniel S.; Zhu, Dongming
2011-01-01
Environmental barrier coatings are being developed and tested for use with SiC/SiC ceramic matrix composite (CMC) gas turbine engine components. Several oxide and silicate based compositons are being studied for use as top-coat and intermediate layers in a three or more layer environmental barrier coating system. Specifically, the room temperature Vickers-indentation-fracture-toughness testing and high-temperature stability reaction studies with Calcium Magnesium Alumino-Silicate (CMAS or "sand") are being conducted using advanced testing techniques such as high pressure burner rig tests as well as high heat flux laser tests.
Tasolamprou, Anna C; Zhang, Lei; Kafesaki, Maria; Koschny, Thomas; Soukoulis, Costas M
2015-06-01
We demonstrate the numerical design and the experimental validation of frequency dependent directional emission from a dielectric photonic crystal structure. The wave propagates through a photonic crystal line-defect waveguide, while a surface layer at the termination of the photonic crystal enables the excitation of surface modes and a subsequent grating layer transforms the surface energy into outgoing propagating waves of the form of a directional beam. The angle of the beam is controlled by the frequency and the structure operates as a frequency splitter in the intermediate and far field region.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tasolamprou, Anna C.; Zhang, Lei; Kafesaki, Maria
2015-05-19
We demonstrate the numerical design and the experimental validation of frequency dependent directional emission from a dielectric photonic crystal structure. The wave propagates through a photonic crystal line-defect waveguide, while a surface layer at the termination of the photonic crystal enables the excitation of surface modes and a subsequent grating layer transforms the surface energy into outgoing propagating waves of the form of a directional beam. Furthermore, the angle of the beam is controlled by the frequency and the structure operates as a frequency splitter in the intermediate and far field region.
Band bending at magnetic Ni/Ge(001) interface investigated by X-ray photoelectron spectroscopy
NASA Astrophysics Data System (ADS)
Bocîrnea, Amelia Elena; Tănase, Liviu Cristian; Costescu, Ruxandra Maria; Apostol, Nicoleta Georgiana; Teodorescu, Cristian Mihail
2017-12-01
We report the molecular beam epitaxy growth of Ni on a clean Ge(001) surface with an intermediate NiGe layer forming at the interface at room temperature. The crystallinity of the substrate is lost after the deposition of more than 2 Ni monolayers. The Schottky barrier formation is investigated by X-ray photoelectron spectroscopy. The method allows us to infer a 0.39-0.45 eV band bending at the interface between the compound and Ge(001). Magneto-optical Kerr effect measurements were conclusive in detecting the ferromagnetic ordering of Ni outermost layers.
Electrochromic window with high reflectivity modulation
Goldner, Ronald B.; Gerouki, Alexandra; Liu, Te-Yang; Goldner, Mark A.; Haas, Terry E.
2000-01-01
A multi-layered, active, thin film, solid-state electrochromic device having a high reflectivity in the near infrared in a colored state, a high reflectivity and transmissivity modulation when switching between colored and bleached states, a low absorptivity in the near infrared, and fast switching times, and methods for its manufacture and switching are provided. In one embodiment, a multi-layered device comprising a first indium tin oxide transparent electronic conductor, a transparent ion blocking layer, a tungsten oxide electrochromic anode, a lithium ion conducting-electrically resistive electrolyte, a complimentary lithium mixed metal oxide electrochromic cathode, a transparent ohmic contact layer, a second indium oxide transparent electronic conductor, and a silicon nitride encapsulant is provided. Through elimination of optional intermediate layers, simplified device designs are provided as alternative embodiments. Typical colored-state reflectivity of the multi-layered device is greater than 50% in the near infrared, bleached-state reflectivity is less than 40% in the visible, bleached-state transmissivity is greater than 60% in the near infrared and greater than 40% in the visible, and spectral absorbance is less than 50% in the range from 0.65-2.5 .mu.m.
The Surface Structure of Ground Metal Crystals
NASA Technical Reports Server (NTRS)
Boas, W.; Schmid, E.
1944-01-01
The changes produced on metallic surfaces as a result of grinding and polishing are not as yet fully understood. Undoubtedly there is some more or less marked change in the crystal structure, at least, in the top layer. Hereby a diffusion of separated crystal particles may be involved, or, on plastic material, the formation of a layer in greatly deformed state, with possible recrystallization in certain conditions. Czochralski verified the existence of such a layer on tin micro-sections by successive observations of the texture after repeated etching; while Thomassen established, roentgenographically by means of the Debye-Scherrer method, the existence of diffused crystal fractions on the surface of ground and polished tin bars, which he had already observed after turning (on the lathe). (Thickness of this layer - 0.07 mm). Whether this layer borders direct on the undamaged base material or whether deformed intermediate layers form the transition, nothing is known. One observation ty Sachs and Shoji simply states that after the turning of an alpha-brass crystal the disturbance starting from the surface, penetrates fairly deep (approx. 1 mm) into the crystal (proof by recrystallization at 750 C).
Linear shoaling of free-surface waves in multi-layer non-hydrostatic models
NASA Astrophysics Data System (ADS)
Bai, Yefei; Cheung, Kwok Fai
2018-01-01
The capability to describe shoaling over sloping bottom is fundamental to modeling of coastal wave transformation. The linear shoaling gradient provides a metric to measure this property in non-hydrostatic models with layer-integrated formulations. The governing equations in Boussinesq form facilitate derivation of the linear shoaling gradient, which is in the form of a [ 2 P + 2 , 2 P ] expansion of the water depth parameter kd with P equal to 1 for a one-layer model and (4 N - 4) for an N-layer model. The expansion reproduces the analytical solution from Airy wave theory at the shallow water limit and maintains a reasonable approximation up to kd = 1.2 and 2 for the one and two-layer models. Additional layers provide rapid and monotonic convergence of the shoaling gradient into deep water. Numerical experiments of wave propagation over a plane slope illustrate manifestation of the shoaling errors through the transformation processes from deep to shallow water. Even though outside the zone of active wave transformation, shoaling errors from deep to intermediate water are cumulative to produce appreciable impact to the wave amplitude in shallow water.
Aggarwal, Neha; Altgärde, Noomi; Svedhem, Sofia; Michanetzis, Georgios; Missirlis, Yannis; Groth, Thomas
2013-10-01
Polyelectrolyte multilayers of chitosan and heparin are assembled on glass where heparin is applied at pH = 4, 9 and 4 during the formation of the first layers followed by pH = 9 at the last steps (denoted pH 4 + 9). Measurements of wetting properties, layer mass, and topography show that multilayers formed at pH = 4 are thicker, contain more water and have a smoother surface compared to those prepared at pH = 9 while the pH = 4 + 9 multilayers expressed intermediate properties. pH = 9 multilayers are more cell adhesive and support growth of C2C12 cells better than pH = 4 ones. However, pH 4 + 9 conditions improve the bioactivity to a similar level of pH = 9 layers. Multilayers prepared using pH 4 + 9 conditions form thick enough layers that may allow efficient loading of bioactive molecules. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Akoglu, Ekin; Salihoglu, Baris; Fach Salihoglu, Bettina; Libralato, Simone; Cannaby, Heather; Oguz, Temel; Solidoro, Cosimo
2014-05-01
A dynamic Ecopath with Ecosim higher-trophic-level (HTL) model representation of the Black Sea ecosystem was coupled to the physical (BIMS-CIR) and biogeochemical (BIMS-ECO) models of the Black Sea in order to investigate historical anthropogenic and climatological interactions and feedbacks in the ecosystem. Further, the coupled models were used to assess the likely consequences of these interactions on the ecosystem's structure and functioning under predicted future climate (IPCC A1B) and fishing variability. Therefore, two model scenarios were used; i) a hindcast scenario (1980-1999) to evaluate and understand the impacts of the short-term climate and physical variability and the introduction of invasive species on the Black Sea ecosystem, and ii) a forecast scenario (2080-2099) to investigate the potential implications of climate change and anthropogenic exploitation on living resources of the Black Sea ecosystem by the end of the 21st century. According to the outcomes of the hindcast simulation, fisheries were found to be the main driver in determining the structure and functioning of the Black Sea ecosystem under changing environmental conditions. The coupled physical-biogeochemical forecast simulations predicted a slight but statistically significant basin-wide increase in the Black Sea's primary productivity by the end of the century due to increased stratification induced by basin-wide temperature increase and reduced Cold Intermediate Layer (CIL) formation which increased the residence time of riverine nutrients within the euphotic zone. Despite this increased primary productivity, the HTL model forecast simulation predicted a significant decrease in the commercial fish stocks primarily due to fisheries exploitation if current catch rates are maintained into the future. Results further suggested that some economically important small pelagic fish species are likely to disappear from the ecosystem making the recovery of the already-collapsed piscivorous fish stocks increasingly unlikely. In addition, a further reduction in the proportion of piscivorous fish in the fish community was found to be consequent. From a management perspective, the results of the study suggested that along with managing fishing exploitation levels of the target stocks, monitoring and management of other species in the ecosystem that are tightly coupled with the fish species in terms of food web interactions were found to be the most effective way of applying an ecosystem-based management strategy in the Black Sea. Such an approach will ensure the sustainable utilisation of the fish stocks of the Black Sea by maintaining the ecological integrity of the Black Sea marine food web.
Smart glass based on electrochromic polymers
NASA Astrophysics Data System (ADS)
Xu, Chunye; Kong, Xiangxing; Liu, Lu; Su, Fengyu; Kim, Sooyeun; Taya, Minoru
2006-03-01
Five-layer-structured electrochromic glass (window), containing a transparent conductive layer, an electrochromic layer, an ionic conductive layer, an ionic storage layer and a second conductive transparent layer, was fabricated. The electrochromic glass adopts the conjugated polymer, poly[3,3-dimethyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine] (PProDOT-Me2), as a blue electrochromic active layer, vanadium pentaoxide film as an ion storage layer and polymer gel electrolyte as the ionic transport layer. Dimension of smart glass up to 12 x 20 inch was developed. UV curable sealant was applied for the sealing devices. Color changing or switching speed of 12 x 20 inch smart glass from dark state to the transparent state (or vise versa) is less than 15 seconds under applied 1.5 voltages. Besides the long open circuit memory (the colored state or transparent state remains the same state after the power is off), the smart window can be adjusted easily into the intermediate state between the dark state and the transparent state by just simply turn the power on or off. No space consuming or dirt collecting shades, curtains or blinds are needed. The applications of the smart window, e.g. in the aircrafts, automobiles and architectures were discussed as well.
Formation mechanism of photo-induced nested wrinkles on siloxane-photomonomer hybrid film
DOE Office of Scientific and Technical Information (OSTI.GOV)
Suzuki, Kazumasa; International Laboratory of Materials Science and Nanotechnology; Laboratorio di Scienz
Nested wrinkle structures, hierarchical surface wrinkles of different periodicities of sub-μm and tens-μm, have been fabricated on a siloxane-photomonomer hybrid film via a photo-induced surface polymerization of acrylamide. The formation mechanism of the nested wrinkle structures is examined based on a time-dependent structure observation and chemical composition analyses. In-situ observation of the evolving surface structure showed that sub-μm scale wrinkles first formed, subsequently the tens-μm scale ones did. In-situ FT-IR analysis indicated that the nested wrinkles formation took place along with the development of siloxane network of under layer. A cross sectional observation of the film revealed that the filmmore » was composed of three layers. FT-IR spectra of the film revealed that the surface and interior layers were polyacrylamide rich layer and siloxane-polymer rich layer, respectively. The intermediate layer formed as a diffusion layer by migration of acrylamide from interior to the surface. These three layers have different chemical compositions and therefore different mechanical characteristics, which allows the wrinkle formation. Shrinkage of siloxane-polymer interior layers, as a result of polycondensation of siloxane network, induced mechanical instabilities at interlayers, to form the nested wrinkle structures.« less
NASA Astrophysics Data System (ADS)
Sepulveda, N.; Rohrer, K.
2008-05-01
The permeability of the semiconfining layers of the highly productive Floridan Aquifer System may be large enough to invalidate the assumptions of the leaky aquifer theory. These layers are the intermediate confining and the middle semiconfining units. The analysis of aquifer-test data with analytical solutions of the ground-water flow equation developed with the approximation of a low hydraulic conductivity ratio between the semiconfining layer and the aquifer may lead to inaccurate hydraulic parameters. An analytical solution is presented here for the flow in a confined leaky aquifer, the overlying storative semiconfining layer, and the unconfined aquifer, generated by a partially penetrating well in a two-aquifer system, and allowing vertical and lateral flow components to occur in the semiconfining layer. The equations describing flow caused by a partially penetrating production well are solved analytically to provide a method to accurately determine the hydraulic parameters in the confined aquifer, semiconfining layer, and unconfined aquifer from aquifer-test data. Analysis of the drawdown data from an aquifer test performed in central Florida showed that the flow solution presented here for the semiconfining layer provides a better match and a more unique identification of the hydraulic parameters than an analytical solution that considers only vertical flow in the semiconfining layer.
The laminar structure of the common opossum masseter (Didelphis marsupialis).
Deguchi, T; Takemura, A; Suwa, F
2001-03-01
Using three heads of the common opossum (Didelphis marsupialis), which may be considered to have a primitive mammalian form and therefore be appropriate for this study, the laminar structure of the masseter was investigated. We also attempted a comparative anatomical study of the relationships of food habits to the laminar structures of the masseter, zygomatic arch and mandibular ramus. In the common opossum masseter, a total of six layers, the primary and secondary sublayers of the superficial layer, the intermediate layer, and the primary, secondary and third sublayers of the deep layer as a proper masseter, were observed. These layers showed a typical reverse laminar structure, with the layers of tendons and muscles alternating. The maxillomandibularis and zygomaticomandibularis muscles were observed in one layer each, as an improper masseter. The laminar structure of the common opossum masseter was shown to be more similar to that of carnivorous placental animals than that of the herbivorous red kangaroo, a similar marsupial. In regard to the number of layers in the laminar structure of the masseter, the results of both this study and those of our predecessors' showed that differences in food habits affect the deep layer in the proper masseter of marsupials and placental mammals, and that of the maxillomandibularis muscle of placental mammals in the improper masseter.
ERIC Educational Resources Information Center
Watkins, Ryan; Engel, Laura C.; Hastedt, Dirk
2015-01-01
The rise of digital information and communication technologies (ICT) has made the acquisition of computer and information literacy (CIL) a leading factor in creating an engaged, informed, and employable citizenry. However, are young people, often described as "digital natives" or the "net generation," developing the necessary…
Independent Orbiter Assessment (IOA): Analysis of the active thermal control subsystem
NASA Technical Reports Server (NTRS)
Sinclair, S. K.; Parkman, W. E.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical (PCIs) items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The independent analysis results corresponding to the Orbiter Active Thermal Control Subsystem (ATCS) are documented. The major purpose of the ATCS is to remove the heat, generated during normal Shuttle operations from the Orbiter systems and subsystems. The four major components of the ATCS contributing to the heat removal are: Freon Coolant Loops; Radiator and Flow Control Assembly; Flash Evaporator System; and Ammonia Boiler System. In order to perform the analysis, the IOA process utilized available ATCS hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode. Of the 310 failure modes analyzed, 101 were determined to be PCIs.
Huan, Tao; Li, Liang
2015-07-21
Generating precise and accurate quantitative information on metabolomic changes in comparative samples is important for metabolomics research where technical variations in the metabolomic data should be minimized in order to reveal biological changes. We report a method and software program, IsoMS-Quant, for extracting quantitative information from a metabolomic data set generated by chemical isotope labeling (CIL) liquid chromatography mass spectrometry (LC-MS). Unlike previous work of relying on mass spectral peak ratio of the highest intensity peak pair to measure relative quantity difference of a differentially labeled metabolite, this new program reconstructs the chromatographic peaks of the light- and heavy-labeled metabolite pair and then calculates the ratio of their peak areas to represent the relative concentration difference in two comparative samples. Using chromatographic peaks to perform relative quantification is shown to be more precise and accurate. IsoMS-Quant is integrated with IsoMS for picking peak pairs and Zero-fill for retrieving missing peak pairs in the initial peak pairs table generated by IsoMS to form a complete tool for processing CIL LC-MS data. This program can be freely downloaded from the www.MyCompoundID.org web site for noncommercial use.
Independent Orbiter Assessment (IOA): Analysis of the hydraulics/water spray boiler subsystem
NASA Technical Reports Server (NTRS)
Duval, J. D.; Davidson, W. R.; Parkman, William E.
1986-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items (PCIs). To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results for the Orbiter Hydraulics/Water Spray Boiler Subsystem. The hydraulic system provides hydraulic power to gimbal the main engines, actuate the main engine propellant control valves, move the aerodynamic flight control surfaces, lower the landing gear, apply wheel brakes, steer the nosewheel, and dampen the external tank (ET) separation. Each hydraulic system has an associated water spray boiler which is used to cool the hydraulic fluid and APU lubricating oil. The IOA analysis process utilized available HYD/WSB hardware drawings, schematics and documents for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode. Of the 430 failure modes analyzed, 166 were determined to be PCIs.
Independent Orbiter Assessment (IOA): Analysis of the remote manipulator system
NASA Technical Reports Server (NTRS)
Tangorra, F.; Grasmeder, R. F.; Montgomery, A. D.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items (PCIs). To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The independent analysis results for the Orbiter Remote Manipulator System (RMS) are documented. The RMS hardware and software are primarily required for deploying and/or retrieving up to five payloads during a single mission, capture and retrieve free-flying payloads, and for performing Manipulator Foot Restraint operations. Specifically, the RMS hardware consists of the following components: end effector; displays and controls; manipulator controller interface unit; arm based electronics; and the arm. The IOA analysis process utilized available RMS hardware drawings, schematics and documents for defining hardware assemblies, components and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode. Of the 574 failure modes analyzed, 413 were determined to be PCIs.
NASA Technical Reports Server (NTRS)
Patton, Jeff A.
1986-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Electrical Power Distribution and Control (EPD and C)/Electrical Power Generation (EPG) hardware. The EPD and C/EPG hardware is required for performing critical functions of cryogenic reactant storage, electrical power generation and product water distribution in the Orbiter. Specifically, the EPD and C/EPG hardware consists of the following components: Power Section Assembly (PSA); Reactant Control Subsystem (RCS); Thermal Control Subsystem (TCS); Water Removal Subsystem (WRS); and Power Reactant Storage and Distribution System (PRSDS). The IOA analysis process utilized available EPD and C/EPG hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.
Independent Orbiter Assessment (IOA): Analysis of the nose wheel steering subsystem
NASA Technical Reports Server (NTRS)
Mediavilla, Anthony Scott
1986-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The independent analysis results for the Orbiter Nose Wheel Steering (NWS) hardware are documented. The NWS hardware provides primary directional control for the Orbiter vehicle during landing rollout. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode. The original NWS design was envisioned as a backup system to differential braking for directional control of the Orbiter during landing rollout. No real effort was made to design the NWS system as fail operational. The brakes have much redundancy built into their design but the poor brake/tire performance has forced the NSTS to upgrade NWS to the primary mode of directional control during rollout. As a result, a large percentage of the NWS system components have become Potential Critical Items (PCI).
Wang, Y; Qiu, L; Dong, J; Wang, B; Shi, Z; Liu, B; Wang, W; Zhang, J; Cai, S; Ye, G; Cai, X
2013-03-01
Intrathecal administration of antibiotics has potentially high effectiveness for the treatment for severe intracranial infections, particularly nosocomial meningitis. The use of intrathecal injection of antibiotics has been reported mostly in case reports. However, there is sparse data regarding the pharmacokinetics of antibiotics after intrathecal administration. This study investigated whether intrathecal injection is an effective method for the administration of imipenem. The pharmacokinetics of imipenem after intrathecal and intravenous administration of 1:1 imipenem: cilastatin (IMI/CIL) to rabbits were compared. The AUC0-t in the cerebrospinal fluid for intrathecal administration was approximately twice that of an equal dose of intravenous administration at doses of 0.35, 0.7, and 1.4 mg/kg. Brain concentrations of imipenem after intrathecal injection were three times greater than observed after intravenous injection and remained high for at least 8 hours post-injection. Elimination of imipenem after administration by either route was primarily via urine, but a transient surge of imipenem in bile and intestinal tissue was observed. Results indicate that there is a clinical potential for intrathecally administered IMI/CIL. Further studies are warranted to investigate the potential for seizure and to assess the translatability of the rabbit model to human treatment.
Steinmetz, Neven J; Aisenbrey, Elizabeth A; Westbrook, Kristofer K; Qi, H Jerry; Bryant, Stephanie J
2015-07-01
A bioinspired multi-layer hydrogel was developed for the encapsulation of human mesenchymal stem cells (hMSCs) as a platform for osteochondral tissue engineering. The spatial presentation of biochemical cues, via incorporation of extracellular matrix analogs, and mechanical cues, via both hydrogel crosslink density and externally applied mechanical loads, were characterized in each layer. A simple sequential photopolymerization method was employed to form stable poly(ethylene glycol)-based hydrogels with a soft cartilage-like layer of chondroitin sulfate and low RGD concentrations, a stiff bone-like layer with high RGD concentrations, and an intermediate interfacial layer. Under a compressive load, the variation in hydrogel stiffness within each layer produced high strains in the soft cartilage-like layer, low strains in the stiff bone-like layer, and moderate strains in the interfacial layer. When hMSC-laden hydrogels were cultured statically in osteochondral differentiation media, the local biochemical and matrix stiffness cues were not sufficient to spatially guide hMSC differentiation after 21 days. However dynamic mechanical stimulation led to differentially high expression of collagens with collagen II in the cartilage-like layer, collagen X in the interfacial layer and collagen I in the bone-like layer and mineral deposits localized to the bone layer. Overall, these findings point to external mechanical stimulation as a potent regulator of hMSC differentiation toward osteochondral cellular phenotypes. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Badía-Romano, L.; Rubín, J.; Magén, C.; Bürgler, D. E.; Bartolomé, J.
2014-07-01
The morphology and the quantitative composition of the Fe-Si interface layer forming at each Fe layer of a (Fe/Si)3 multilayer have been determined by means of conversion electron Mössbauer spectroscopy (CEMS) and high-resolution transmission electron microscopy (HRTEM). For the CEMS measurements, each layer was selected by depositing the Mössbauer active 57Fe isotope with 95% enrichment. Samples with Fe layers of nominal thickness dFe = 2.6 nm and Si spacers of dSi = 1.5 nm were prepared by thermal evaporation onto a GaAs(001) substrate with an intermediate Ag(001) buffer layer. HRTEM images showed that Si layers grow amorphous and the epitaxial growth of the Fe is good only for the first deposited layer. The CEMS spectra show that at all Fe/Si and Si/Fe interfaces a paramagnetic c-Fe1-xSi phase is formed, which contains 16% of the nominal Fe deposited in the Fe layer. The bottom Fe layer, which is in contact with the Ag buffer, also contains α-Fe and an Fe1-xSix alloy that cannot be attributed to a single phase. In contrast, the other two layers only comprise an Fe1-xSix alloy with a Si concentration of ≃0.15, but no α-Fe.
Highly efficient tandem polymer solar cells with a photovoltaic response in the visible light range.
Zheng, Zhong; Zhang, Shaoqing; Zhang, Maojie; Zhao, Kang; Ye, Long; Chen, Yu; Yang, Bei; Hou, Jianhui
2015-02-18
Highly efficient polymer solar cells with a tandem structure are fabricated by using two excellent photovoltaic polymers and a highly transparent intermediate recombination layer. Power conversion -efficiencies over 10% can be realized with a photovoltaic response within 800 nm. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Technical Reports Server (NTRS)
Forman, R.
1979-01-01
Auger spectra and work function measurements are used to study the surface reactions between tungsten surface and adsorbed layers of barium, and barium and oxygen. The barium on an impregnated tungsten cathod seems to be an intermediate state, probably a coadsorbed barium-oxygen layer on tungsten. A slightly revised version of the previously suggested (1976) impregnated tungsten cathode model is proposed. This revised model assumes that the cathode surface during life has an adsorbed surface layer of a monolayer or less of both barium and oxygen on the surface. At end of life, steep drop in electron emission and resultant cathode failure occur. Recent NASA life test results on TWT type tubes are reported and explained by the proposed model.
Mao, Shan; Cui, Qingfeng; Piao, Mingxu; Zhao, Lidong
2016-05-01
A mathematical model of diffraction efficiency and polychromatic integral diffraction efficiency affected by environment temperature change and incident angle for three-layer diffractive optics with different dispersion materials is put forward, and its effects are analyzed. Taking optical materials N-FK5 and N-SF1 as the substrates of multilayer diffractive optics, the effect on diffraction efficiency and polychromatic integral diffraction efficiency with intermediate materials POLYCARB is analyzed with environment temperature change as well as incident angle. Therefore, three-layer diffractive optics can be applied in more wide environmental temperature ranges and larger incident angles for refractive-diffractive hybrid optical systems, which can obtain better image quality. Analysis results can be used to guide the hybrid imaging optical system design for optical engineers.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1986-01-01
The goal of this program is to develop polymer membranes useful in the preparation of hydrogen from coal-derived synthesis gas. During this quarter the first experiment were aimed at developing high performance composite membranes for the separation of hydrogen from nitrogen and carbon monoxide. Three polymers have been selected as materials for these membranes: polyetherimide cellulose acetate and ethylcellulose. This quarter the investigators worked on polyetherimide and cellulose acetate membranes. The overall structure of these membranes is shown schematically in Figure 1. As shown, a microporous support membrane is first coated with a high flux intermediate layer then with anmore » ultrathin permselective layer and finally, if necessary, a thin protective high flux layer. 1 fig., 4 tabs.« less
NASA Astrophysics Data System (ADS)
Yoo, Y.-S.; Park, J.-W.; Park, J.-K.; Lim, H.-C.; Oh, J.-M.; Bae, J.-M.
Recent results on intermediate temperature-operating solid oxide fuel cells (IT-SOFC) are mainly focused on getting the higher performance of single cell at lower operating temperature, especially using planar type. We have started a project to develop 1 kW-class SOFC system for Residential Power Generation(RPG) application. For a 1 kW-class SOFC stack that can be operated at intermediate temperatures, we have developed anode-supported, planar type SOFC to have advantages for commercialization of SOFCs considering mass production and using cost-effective interconnects such as ferritic stainless steels. At higher temperature, performance of SOFC can be increased due to higher electrochemical activity of electrodes and lower ohmic losses, but the surface of metallic interconnects at cathode side is rapidly oxidized into resistive oxide scale. For efficient operation of SOFC at reduced temperature at, firstly we have developed alternative cathode materials of LSCF instead of LSM to get higher performance of electrodes, and secondly introduced functional-layered structure at anode side. The I-V and AC impedance characteristics of improved single cells and small stacks were evaluated at intermediate temperatures (650°C and 750°C) using hydrogen gas as a fuel.
Iwasaki, S; Asami, T; Wanichanon, C
1996-04-01
Various species of turtles are adapted to different environments, such as freshwater, seawater, and terrestrial habitats. Comparisons of histological and ultrastructural features of the tongue of the juvenile Hawksbill turtle, Eretmochelys imbricata bissa, with those of freshwater turtles should reveal some aspects of the relationship between the structure of the lingual epithelium and the environment. The light microscope, scanning electron microscope and transmission electron microscope were used. Light microscopy revealed that the mucosal epithelium of the tongue was of the keratinized, stratified squamous type. Under the scanning electron microscope, no lingual papillae were visible on the dorsal surface of the tongue. Micropits and the thickening of cell margins were clearly seen on the surface of cells located on the outermost side. The transmission electron microscope revealed that the cells in the intermediate layer were gradually flattened from the basal side to the surface side, as were their nuclei. In the shallow intermediate layer, the cells were significantly flattened, and their nuclei were condensed or had disappeared. The cytoplasm contained keratohyalin granules, tonofibrils, free ribosomes, mitochondria, and rough endoplasmic reticulum. Numerous free ribosomes were attached to the surface of small keratohyalin granules. The cells of the keratinized layer were significantly flattened, and their nuclei had completely disappeared. Most of cytoplasm was filled with keratin fibers of high electron density. Keratin fibers of the shedding cells, which were located on the outermost side of the keratinized layer, appeared looser, and each fiber, which was somewhat thicker than the tonofibrils and tonofilaments, was clearly distinguishable. The lingual epithelium of the juvenile Hawksbill turtle differs significantly from that of the adult freshwater turtle, in spite of the similarity in gross morphology of the tongues of these species.
Observations of the summer Red Sea circulation
NASA Astrophysics Data System (ADS)
Sofianos, Sarantis S.; Johns, William E.
2007-06-01
Aiming at exploring and understanding the summer circulation in the Red Sea, a cruise was conducted in the basin during the summer of 2001 involving hydrographic, meteorological, and direct current observations. The most prominent feature, characteristic of the summer circulation and exchange with the Indian Ocean, is a temperature, salinity, and oxygen minimum located around a depth of 75 m at the southern end of the basin, associated with Gulf of Aden Intermediate Water inflowing from the Gulf of Aden during the summer season as an intruding subsurface layer. Stirring and mixing with ambient waters lead to marked increases in temperature (from 16.5 to almost 33°C) and salinity (from 35.7 to more than 38 psu) in this layer by the time it reaches midbasin. The observed circulation presents a very vigorous pattern with strong variability and intense features that extend the width of the basin. A permanent cyclone, detected in the northern Red Sea, verifies previous observations and modeling studies, while in the central sector of the basin a series of very strong anticyclones were observed with maximum velocities exceeding 1 m/s. The three-layer flow pattern, representative of the summer exchange between the Red Sea and the Gulf of Aden, is observed in the strait of Bab el Mandeb. In the southern part of the basin the layer flow is characterized by strong banking of the inflows and outflows against the coasts. Both surface and intermediate water masses involved in the summer Red Sea circulation present prominent spatial variability in their characteristics, indicating that the eddy field and mixing processes play an important role in the summer Red Sea circulation.
NASA Astrophysics Data System (ADS)
Mailhot, B.; Rivaton, A.; Gardette, J.-L.; Moustaghfir, A.; Tomasella, E.; Jacquet, M.; Ma, X.-G.; Komvopoulos, K.
2006-05-01
The chemical reactions resulting from ultraviolet radiation produce discoloration and significant changes in the surface properties of polycarbonate (PC). To prevent photon absorption from irradiation and oxygen diffusion and to enhance the surface nanomechanical properties of PC, thin ceramic coatings of ZnO and Al2O3 (both single- and multi-layer) were deposited on bulk PC by radio-frequency magnetron sputtering. The samples were irradiated at wavelengths greater than 300 nm, representative of outdoor conditions. Despite the effectiveness of ZnO to protect PC from irradiation damage, photocatalytic oxidation at the PC/ZnO interface was the limiting factor. To overcome this deficiency, a thin Al2O3 coating was used both as intermediate and top layer because of its higher hardness and wear resistance than ZnO. Therefore, PC/Al2O3/ZnO, PC/ZnO/Al2O3, and PC/Al2O3/ZnO/Al2O3 layered media were fabricated and their photodegradation properties were examined by infrared and ultraviolet-visible spectroscopy. It was found that the photocatalytic activity at the PC/ZnO interface was reduced in the presence of the intermediate Al2O3 layer that limited the oxygen permeability. Nanomechanical experiments performed with a surface force apparatus revealed that the previous coating systems enhanced both the surface nanohardness and the elastic modulus and reduced the coefficient of friction in the order of ZnO, Al2O3, and Al2O3/ZnO/Al2O3. Although irradiation increased the nanohardness and the elastic modulus of PC, the irradiation effect on the surface mechanical properties of ceramic-coated PC was secondary.
NASA Astrophysics Data System (ADS)
Coppola, Laurent; Legendre, Louis; Lefevre, Dominique; Prieur, Louis; Taillandier, Vincent; Diamond Riquier, Emilie
2018-03-01
Dissolved oxygen (O2) is a relevant tracer to interpret variations of both water mass properties in the open ocean and biological production in the surface layer of both coastal and open waters. Deep-water formation is very active in the northwestern Mediterranean Sea, where it influences intermediate and deep waters properties, nutrients replenishment and biological production. This study analyses, for the first time, the 20-year time series of monthly O2 concentrations at the DYFAMED long-term sampling site in the Ligurian Sea. Until the winters of 2005 and 2006, a thick and strong oxygen minimum layer was present between 200 and 1300 m because dense water formation was then local, episodic and of low intensity. In 2005-2006, intense and rapid deep convection injected 24 mol O2 m-2 between 350 and 2000 m from December 2005 to March 2006. Since this event, the deep layer has been mostly ventilated during winter time by newly formed deep water spreading from the Gulf of Lion 250 km to the west and by some local deep mixing in early 2010, 2012 and 2013. In the context of climate change, it is predicted that the intensity of deep convection will become weaker in the Mediterranean, which could potentially lead to hypoxia in intermediate and deep layers with substantial impact on marine ecosystems. With the exception of winters 2005 and 2006, the O2 changes in surface waters followed a seasonal trend that reflected the balance between air-sea O2 exchanges, changes in the depth of the mixed layer and phytoplankton net photosynthesis. We used the 20-year O2 time series to estimate monthly and annual net community production. The latter was 7.1 mol C m-2 yr-1, consistent with C-14 primary production determinations and sediment-trap carbon export fluxes at DYFAMED.
Methods to improve the PVD coatability of brass by using diffusion barriers
NASA Astrophysics Data System (ADS)
Langer, Bernd
Previous work involving PVD coatings on brass has used a combination of multilayers consisting of electroplated films like nickel or chromium and deposited decorative PVD coatings like TiN, TiAIN or ZrN systems. The disadvantages of these systems are the combination of wet electrochemistry and high tech vacuum processes. Furthermore the allergic reaction to nickel and the toxic nature of Cr(VI) must be considered.There is a need for intermediate layers to 'seal-off the brass in order to avoid the evaporation of zinc in vacuum using a diffusion barrier. Furthermore the intermediate layers are required to act as a corrosion barrier.This thesis reports on the development of PVD coatings on heat sensitive brass substrate materials utilising ABS technology with Al, CuAl8 and Nb targets as vapour sources.The brass pretreatment includes careful grinding, polishing and cleaning steps as well as steered arc metal ion etching using the above target materials. The coatings are produced at temperatures between 100 and 250°C in the unbalanced magnetron mode, including layers made from Al, Al-Nb, CuA18, CuAl8-Nb and Nb.Scratch adhesion and Rockwell indentation tests are found not to be directly applicable to the system of soft brass and ductile coating(s). Therefore a new classification for both scratch and indentation tests was defined. The best adhesion was shown by the CuA18 coatings on brass. Corrosion tests showed good results for the Al coatings and poor results for the pure Nb coatings directly applied on brass. The best corrosion result was obtained with a CuAl8-Nb layer system. This layer system also offers very good barrier behaviour concerning Zn diffusion.Other investigations like Glow Discharge Optical Emission Spectroscopy (GDOES), Scanning Electron Microscopy (SEM) imaging, Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD) were undertaken to characterise the new coating systems for brass.
Arctic Intermediate Water in the Nordic Seas, 1991-2009
NASA Astrophysics Data System (ADS)
Jeansson, Emil; Olsen, Are; Jutterström, Sara
2017-10-01
The evolution of the different types of Arctic Intermediate Water (AIW) in the Nordic Seas is evaluated and compared utilising hydro-chemical data from 1991 to 2009. It has been suggested that these waters are important components of the Norwegian Sea Arctic Intermediate Water (NSAIW), and of the dense overflows to the North Atlantic. Thus, it is important to understand how their properties and distribution vary with time. The AIWs from the Greenland and Iceland Seas, show different degrees of variability during the studied period; however, only the Greenland Sea Arctic Intermediate Water (GSAIW) shows an increasing temperature and salinity throughout the 2000s, which considerably changed the properties of this water mass. Optimum multiparameter (OMP) analysis was conducted to assess the sources of the NSAIW. The analysis shows that the Iceland Sea Arctic Intermediate Water (ISAIW) and the GSAIW both contribute to NSAIW, at different densities corresponding to their respective density range. This illustrates that they flow largely isopycnally from their source regions to the Norwegian Sea. The main source of the NSAIW, however, is the upper Polar Deep Water, which explains the lower concentrations of oxygen and chlorofluorocarbons, and higher salinity and nutrient concentrations of the NSAIW layer compared with the ISAIW and GSAIW. This shows how vital it is to include chemical tracers in any water mass analysis to correctly assess the sources of the water mass being studied.
NASA Technical Reports Server (NTRS)
Jochum, Markus
2002-01-01
A numerical model of the tropical Atlantic ocean is used to investigate the upper layer pathways of the Meridional Overturning Circulation (MOC) in the tropical Atlantic. The main focus of this thesis is on those parts of the tropical circulation that are thought to be important for the MOC return flow, but whose dynamics have not been understood yet. It is shown how the particular structure of the tropical gyre and the MOO act to inhibit the flow of North Atlantic water into the equatorial thermocline. As a result, the upper layers of the tropical Atlantic are mainly fed by water from the South Atlantic. The processes that carry the South Atlantic water across the tropical Atlantic into the North Atlantic as part of the MOO are described here, and three processes that were hitherto not understood are explained as follows: The North Brazil Current rings are created as the result of the reflection of Rossby waves at the South American coast. These Rossby waves are generated by the barotropically unstable North Equatorial Countercurrent. The deep structure of the rings can be explained by merger of the wave's anticyclones with the deeper intermediate eddies that are generated as the intermediate western boundary current crosses the equator. The bands of strong zonal velocity in intermediate depths along the equator have hitherto been explained as intermediate currents. Here, an alternative interpretation of the observations is offered: The Eulerian mean flow along the equator is negligible and the observations are the signature of strong seasonal Rossby waves. The previous interpretation of the observations can then be explained as aliasing of the tropical wave field. The Tsuchyia Jets are driven by the Eliassen-Palm flux of the tropical instability waves. The equatorial current system with its strong shears is unstable and generates tropical instability waves.
NASA Astrophysics Data System (ADS)
Kundu, S.; Sam, S.; Mishra, B.; Chatterjee, S.
2014-01-01
The interface microstructure and strength properties of solid state diffusion bonding of microduplex stainless steel (MDSS) to Ti alloy (TiA) with and without a Ni alloy (NiA) intermediate material were investigated at 1173 K (900 °C) for 0.9 to 5.4 ks in steps of 0.9 ks in vacuum. The effects of bonding time on the microstructure of the bonded joint have been analyzed by light optical microscopy and scanning electron microscopy in the backscattered mode. In the direct bonded joints of MDSS and TiA, the layer-wise σ phase and the λ + FeTi phase mixture were observed at the bond interface when the joint was processed for 2.7 ks and above holding times. However, when NiA was used as an intermediate material, the results indicated that TiNi3, TiNi, and Ti2Ni are formed at the NiA-TiA interface, and the irregular shaped particles of Fe22Mo20Ni45Ti13 have been observed within the TiNi3 intermetallic layer. The stainless steel-NiA interface is free from intermetallics and the layer of austenitic phase was observed at the stainless steel side. A maximum tensile strength of ~520 MPa, shear strength of ~405 MPa, and impact toughness of ~18 J were obtained for the directly bonded joint when processed for 2.7 ks. However, when nickel base alloy was used as an intermediate material in the same materials, the bond tensile and shear strengths increase to ~640 and ~479 MPa, respectively, and the impact toughness to ~21 J when bonding was processed for 4.5 ks. Fracture surface observations in scanning electron microscopy using energy dispersive spectroscopy demonstrate that in MDSS-TiA joints, failure takes place through the FeTi + λ phase when bonding was processed for 2.7 ks; however, failure takes place through σ phase for the diffusion joints processed for 3.6 ks and above processing times. However, in MDSS-NiA-TiA joints, the fracture takes place through NiTi2 layer at the NiA-TiA interface for all bonding times.